From d1c2225c647e01f84c9aa80fc1d5d034754b94c5 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 10:44:08 -0300
Subject: QGraphicsAnchorLayout: Ensure spacing is not negative

Currently we do not support negative-sized anchors in the graph,
instead we invert such anchors and make their value positive.

We consider changing this sometime in the future but until then,
spacing must be non-negative at all times.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout.cpp   | 26 ++++++++++++++++++++++++
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp |  7 +++++++
 2 files changed, 33 insertions(+)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout.cpp b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
index ffbb67c..9f4a19b 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
@@ -306,6 +306,13 @@ void QGraphicsAnchorLayout::addAnchors(QGraphicsLayoutItem *firstItem,
 void QGraphicsAnchorLayout::setHorizontalSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### We don't support negative spacing yet
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[0] = spacing;
     invalidate();
 }
@@ -318,6 +325,13 @@ void QGraphicsAnchorLayout::setHorizontalSpacing(qreal spacing)
 void QGraphicsAnchorLayout::setVerticalSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### We don't support negative spacing yet
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[1] = spacing;
     invalidate();
 }
@@ -327,11 +341,23 @@ void QGraphicsAnchorLayout::setVerticalSpacing(qreal spacing)
 
     If an item is anchored with no spacing associated with the anchor, it will use the default
     spacing.
+
+    Currently QGraphicsAnchorLayout does not support negative default spacings.
+
     \sa setHorizontalSpacing(), setVerticalSpacing()
 */
 void QGraphicsAnchorLayout::setSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### Currently we do not support negative anchors inside the graph.
+    // To avoid those being created by a negative spacing, we must
+    // make this test.
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[0] = d->spacings[1] = spacing;
     invalidate();
 }
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index e3cd4f9..9524289 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1550,6 +1550,13 @@ qreal QGraphicsAnchorLayoutPrivate::effectiveSpacing(Orientation orientation) co
             }
         }
     }
+
+    // ### Currently we do not support negative anchors inside the graph.
+    // To avoid those being created by a negative style spacing, we must
+    // make this test.
+    if (s < 0)
+        s = 0;
+
     return s;
 }
 
-- 
cgit v0.12


From 6dc050639aeac0021bcb7864533779f2156e9d24 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 14:30:57 -0300
Subject: QGraphicsAnchorLayout: Add test for 'infinite' max size widgets

With four items anchored side by side, each of them being allowed
to grow to QWIDGETSIZE_MAX, we have a situation of fair distribution
because the layout itself can grow only to QWIDGETSIZE_MAX (and not
four times this amount).

This test identified an error on the expanding distribution logic.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 .../tst_qgraphicsanchorlayout.cpp                  | 49 ++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index 286ea2d..cf4e9b8 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -73,6 +73,7 @@ private slots:
     void expandingSequenceFairDistribution();
     void expandingParallel();
     void floatConflict();
+    void infiniteMaxSizes();
 };
 
 class RectWidget : public QGraphicsWidget
@@ -1585,5 +1586,53 @@ void tst_QGraphicsAnchorLayout::floatConflict()
     delete p;
 }
 
+void tst_QGraphicsAnchorLayout::infiniteMaxSizes()
+{
+    QGraphicsAnchorLayout *l = new QGraphicsAnchorLayout;
+    l->setContentsMargins(0, 0, 0, 0);
+    l->setSpacing(0);
+
+    QSizeF min(10, 10);
+    QSizeF pref(50, 10);
+    QSizeF max(QWIDGETSIZE_MAX, 10);
+
+    QGraphicsWidget *a = createItem(min, pref, max, "a");
+    QGraphicsWidget *b = createItem(min, pref, max, "b");
+    QGraphicsWidget *c = createItem(min, pref, max, "c");
+    QGraphicsWidget *d = createItem(min, pref, max, "d");
+
+    //<!-- Trunk -->
+    setAnchor(l, l, Qt::AnchorLeft, a, Qt::AnchorLeft, 0);
+    setAnchor(l, a, Qt::AnchorRight, b, Qt::AnchorLeft, 0);
+    setAnchor(l, b, Qt::AnchorRight, c, Qt::AnchorLeft, 0);
+    setAnchor(l, c, Qt::AnchorRight, d, Qt::AnchorLeft, 0);
+    setAnchor(l, d, Qt::AnchorRight, l, Qt::AnchorRight, 0);
+
+    a->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
+    c->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
+
+    QGraphicsWidget p;
+    p.setLayout(l);
+
+    p.resize(200, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, 50, 10));
+    QCOMPARE(b->geometry(), QRectF(50, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(100, 0, 50, 10));
+    QCOMPARE(d->geometry(), QRectF(150, 0, 50, 10));
+
+    p.resize(1000, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, 450, 10));
+    QCOMPARE(b->geometry(), QRectF(450, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(500, 0, 450, 10));
+    QCOMPARE(d->geometry(), QRectF(950, 0, 50, 10));
+
+    qreal expMaxSize = (QWIDGETSIZE_MAX - 100.0) / 2;
+    p.resize(QWIDGETSIZE_MAX, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, expMaxSize, 10));
+    QCOMPARE(b->geometry(), QRectF(expMaxSize, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(expMaxSize + 50, 0, expMaxSize, 10));
+    QCOMPARE(d->geometry(), QRectF(QWIDGETSIZE_MAX - 50, 0, 50, 10));
+}
+
 QTEST_MAIN(tst_QGraphicsAnchorLayout)
 #include "tst_qgraphicsanchorlayout.moc"
-- 
cgit v0.12


From efb50541b57191e3fcfc8dac5a8e8a21658b75b1 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 15:47:42 -0300
Subject: QGraphicsAnchorLayout: Fix sequential anchor distribution w/
 expanding sizes

After the addition of expanding SizePolicy, the distribution of sequential
anchors became wrong.

We must now account for three intervals of distribution instead of only two.
This commit also unifies the logic used by the sequential group anchor and
the edge interpolator.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 162 +++++++++++------------
 1 file changed, 76 insertions(+), 86 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 9524289..1935c27 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -250,44 +250,61 @@ void ParallelAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
      0 is at Preferred
      1 is at Maximum
 */
-static qreal getFactor(qreal value, qreal min, qreal pref, qreal max)
-{
-    // ### Maybe remove some of the assertions? (since outside is asserting us)
-    Q_ASSERT(value > min || qFuzzyCompare(value, min));
-    Q_ASSERT(value < max || qFuzzyCompare(value, max));
-
-    if (qFuzzyCompare(value, min)) {
-        return -1.0;
-    } else if (qFuzzyCompare(value, pref)) {
-        return 0.0;
-    } else if (qFuzzyCompare(value, max)) {
-        return 1.0;
-    } else if (value < pref) {
-        // Since value < pref and value != pref and min <= value,
-        // we can assert that min < pref.
-        Q_ASSERT(min < pref);
-        return (value - min) / (pref - min) - 1;
+static QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> getFactor(qreal value, qreal min,
+                                                                      qreal pref, qreal exp,
+                                                                      qreal max)
+{
+    QGraphicsAnchorLayoutPrivate::Interval interval;
+    qreal lower;
+    qreal upper;
+
+    if (value < pref) {
+        interval = QGraphicsAnchorLayoutPrivate::MinToPreferred;
+        lower = min;
+        upper = pref;
+    } else if (value < exp) {
+        interval = QGraphicsAnchorLayoutPrivate::PreferredToExpanding;
+        lower = pref;
+        upper = exp;
     } else {
-        // Since value > pref and value != pref and max >= value,
-        // we can assert that max > pref.
-        Q_ASSERT(max > pref);
-        return (value - pref) / (max - pref);
+        interval = QGraphicsAnchorLayoutPrivate::ExpandingToMax;
+        lower = exp;
+        upper = max;
     }
+
+    qreal progress;
+    if (upper == lower) {
+        progress = 0;
+    } else {
+        progress = (value - lower) / (upper - lower);
+    }
+
+    return qMakePair(interval, progress);
 }
 
-static qreal getExpandingFactor(qreal expSize, qreal sizeAtPreferred,
-                                qreal sizeAtExpanding, qreal sizeAtMaximum)
+static qreal interpolate(const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> &factor,
+                         qreal min, qreal pref,
+                         qreal exp, qreal max)
 {
-    const qreal lower = qMin(sizeAtPreferred, sizeAtMaximum);
-    const qreal upper = qMax(sizeAtPreferred, sizeAtMaximum);
-    const qreal boundedExpSize = qBound(lower, expSize, upper);
+    qreal lower;
+    qreal upper;
 
-    const qreal bandSize = sizeAtMaximum - boundedExpSize;
-    if (bandSize == 0) {
-        return 0;
-    } else {
-        return (sizeAtExpanding - boundedExpSize) / bandSize;
+    switch (factor.first) {
+    case QGraphicsAnchorLayoutPrivate::MinToPreferred:
+        lower = min;
+        upper = pref;
+        break;
+    case QGraphicsAnchorLayoutPrivate::PreferredToExpanding:
+        lower = pref;
+        upper = exp;
+        break;
+    case QGraphicsAnchorLayoutPrivate::ExpandingToMax:
+        lower = exp;
+        upper = max;
+        break;
     }
+
+    return lower + factor.second * (upper - lower);
 }
 
 void SequentialAnchorData::updateChildrenSizes()
@@ -307,27 +324,22 @@ void SequentialAnchorData::updateChildrenSizes()
     // Band here refers if the value is in the Minimum To Preferred
     // band (the lower band) or the Preferred To Maximum (the upper band).
 
-    const qreal minFactor = getFactor(sizeAtMinimum, minSize, prefSize, maxSize);
-    const qreal prefFactor = getFactor(sizeAtPreferred, minSize, prefSize, maxSize);
-    const qreal maxFactor = getFactor(sizeAtMaximum, minSize, prefSize, maxSize);
-    const qreal expFactor = getExpandingFactor(expSize, sizeAtPreferred, sizeAtExpanding, sizeAtMaximum);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> minFactor =
+        getFactor(sizeAtMinimum, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> prefFactor =
+        getFactor(sizeAtPreferred, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> expFactor =
+        getFactor(sizeAtExpanding, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> maxFactor =
+        getFactor(sizeAtMaximum, minSize, prefSize, expSize, maxSize);
 
     for (int i = 0; i < m_edges.count(); ++i) {
         AnchorData *e = m_edges.at(i);
 
-        qreal bandSize = minFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtMinimum = e->prefSize + bandSize * minFactor;
-
-        bandSize = prefFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtPreferred = e->prefSize + bandSize * prefFactor;
-
-        bandSize = maxFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtMaximum = e->prefSize + bandSize * maxFactor;
-
-        const qreal lower = qMin(e->sizeAtPreferred, e->sizeAtMaximum);
-        const qreal upper = qMax(e->sizeAtPreferred, e->sizeAtMaximum);
-        const qreal edgeBoundedExpSize = qBound(lower, e->expSize, upper);
-        e->sizeAtExpanding = edgeBoundedExpSize + expFactor * (e->sizeAtMaximum - edgeBoundedExpSize);
+        e->sizeAtMinimum = interpolate(minFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtPreferred = interpolate(prefFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtExpanding = interpolate(expFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtMaximum = interpolate(maxFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
 
         e->updateChildrenSizes();
     }
@@ -2161,39 +2173,26 @@ void QGraphicsAnchorLayoutPrivate::calculateVertexPositions(
   \internal
 
   Calculate interpolation parameters based on current Layout Size.
-  Must once before calling "interpolateEdgeSize()" for each edge.
+  Must be called once before calling "interpolateEdgeSize()" for
+  the edges.
 */
 void QGraphicsAnchorLayoutPrivate::setupEdgesInterpolation(
     Orientation orientation)
 {
     Q_Q(QGraphicsAnchorLayout);
-    qreal lower, upper, current;
 
-    if (orientation == Horizontal) {
-        current = q->contentsRect().width();
-    } else {
-        current = q->contentsRect().height();
-    }
+    qreal current;
+    current = (orientation == Horizontal) ? q->contentsRect().width() : q->contentsRect().height();
 
-    if (current < sizeHints[orientation][Qt::PreferredSize]) {
-        interpolationInterval[orientation] = MinToPreferred;
-        lower = sizeHints[orientation][Qt::MinimumSize];
-        upper = sizeHints[orientation][Qt::PreferredSize];
-    } else if (current < sizeAtExpanding[orientation]) {
-        interpolationInterval[orientation] = PreferredToExpanding;
-        lower = sizeHints[orientation][Qt::PreferredSize];
-        upper = sizeAtExpanding[orientation];
-    } else {
-        interpolationInterval[orientation] = ExpandingToMax;
-        lower = sizeAtExpanding[orientation];
-        upper = sizeHints[orientation][Qt::MaximumSize];
-    }
+    QPair<Interval, qreal> result;
+    result = getFactor(current,
+                       sizeHints[orientation][Qt::MinimumSize],
+                       sizeHints[orientation][Qt::PreferredSize],
+                       sizeAtExpanding[orientation],
+                       sizeHints[orientation][Qt::MaximumSize]);
 
-    if (upper == lower) {
-        interpolationProgress[orientation] = 0;
-    } else {
-        interpolationProgress[orientation] = (current - lower) / (upper - lower);
-    }
+    interpolationInterval[orientation] = result.first;
+    interpolationProgress[orientation] = result.second;
 }
 
 /*!
@@ -2220,20 +2219,11 @@ void QGraphicsAnchorLayoutPrivate::interpolateEdge(AnchorVertex *base,
                                                    AnchorData *edge,
                                                    Orientation orientation)
 {
-    qreal lower, upper;
-
-    if (interpolationInterval[orientation] == MinToPreferred) {
-        lower = edge->sizeAtMinimum;
-        upper = edge->sizeAtPreferred;
-    } else if (interpolationInterval[orientation] == PreferredToExpanding) {
-        lower = edge->sizeAtPreferred;
-        upper = edge->sizeAtExpanding;
-    } else {
-        lower = edge->sizeAtExpanding;
-        upper = edge->sizeAtMaximum;
-    }
+    const QPair<Interval, qreal> factor(interpolationInterval[orientation],
+                                        interpolationProgress[orientation]);
 
-    qreal edgeDistance = (interpolationProgress[orientation] * (upper - lower)) + lower;
+    qreal edgeDistance = interpolate(factor, edge->sizeAtMinimum, edge->sizeAtPreferred,
+                                     edge->sizeAtExpanding, edge->sizeAtMaximum);
 
     Q_ASSERT(edge->from == base || edge->to == base);
 
-- 
cgit v0.12


From cce279d015ccf19200153b43b7f378e25d0913d3 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Wed, 7 Oct 2009 19:34:09 -0300
Subject: QGAL: improve dump graph and add helper code

The graph dumper function take a name, and added debug code (that need
to be enabled manually) to generate dumps from the graph before and
after calculation. This is useful to debug simplification.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 14 ++++++++++++--
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |  2 +-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 1935c27..c921b60 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1584,9 +1584,19 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs()
     if (!calculateGraphCacheDirty)
         return;
 
+#if defined(QT_DEBUG) && 0
+    static int count = 0;
+    count++;
+    dumpGraph(QString::fromAscii("%1-before").arg(count));
+#endif
+
     calculateGraphs(Horizontal);
     calculateGraphs(Vertical);
 
+#if defined(QT_DEBUG) && 0
+    dumpGraph(QString::fromAscii("%1-after").arg(count));
+#endif
+
     calculateGraphCacheDirty = 0;
 }
 
@@ -2558,9 +2568,9 @@ bool QGraphicsAnchorLayoutPrivate::hasConflicts() const
 }
 
 #ifdef QT_DEBUG
-void QGraphicsAnchorLayoutPrivate::dumpGraph()
+void QGraphicsAnchorLayoutPrivate::dumpGraph(const QString &name)
 {
-    QFile file(QString::fromAscii("anchorlayout.dot"));
+    QFile file(QString::fromAscii("anchorlayout.%1.dot").arg(name));
     if (!file.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate))
         qWarning("Could not write to %s", file.fileName().toLocal8Bit().constData());
 
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 24b25de..ea19ecb 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -478,7 +478,7 @@ public:
     bool hasConflicts() const;
 
 #ifdef QT_DEBUG
-    void dumpGraph();
+    void dumpGraph(const QString &name = QString());
 #endif
 
 
-- 
cgit v0.12


From b6be5eb62a79f7c0d3718a05b18dcf69d2c21550 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Wed, 7 Oct 2009 19:41:32 -0300
Subject: QGAL: add a way to test whether simplex was used in a calculation

This is one good way to track whether simplification is doing all its
job or not. However it can only track cases where the graph simplify
to only one anchor. For more complex cases the graph dumps are the way
to go.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp   |  8 ++++
 src/gui/graphicsview/qgraphicsanchorlayout_p.h     |  4 ++
 .../tst_qgraphicsanchorlayout.cpp                  | 54 +++++++++++++++++++++-
 3 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index c921b60..b92d1c3 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1689,6 +1689,10 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
+#ifdef QT_DEBUG
+        lastCalculationUsedSimplex[orientation] = true;
+#endif
+
         // Solve min and max size hints for trunk
         qreal min, max;
         feasible = solveMinMax(trunkConstraints, trunkPath, &min, &max);
@@ -1738,6 +1742,10 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
+#ifdef QT_DEBUG
+        lastCalculationUsedSimplex[orientation] = false;
+#endif
+
         // No Simplex is necessary because the path was simplified all the way to a single
         // anchor.
         Q_ASSERT(trunkPath.positives.count() == 1);
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index ea19ecb..7d38e40 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -513,6 +513,10 @@ public:
     bool graphHasConflicts[2];
     QSet<QGraphicsLayoutItem *> m_nonFloatItems[2];
 
+#ifdef QT_DEBUG
+    bool lastCalculationUsedSimplex[2];
+#endif
+
     uint calculateGraphCacheDirty : 1;
 };
 
diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index cf4e9b8..cef56b9 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -153,6 +153,15 @@ static bool layoutHasConflict(QGraphicsAnchorLayout *l)
     return QGraphicsAnchorLayoutPrivate::get(l)->hasConflicts();
 }
 
+static bool usedSimplex(QGraphicsAnchorLayout *l, Qt::Orientation o)
+{
+    QGraphicsAnchorLayoutPrivate::Orientation oo = (o == Qt::Horizontal) ?
+        QGraphicsAnchorLayoutPrivate::Horizontal :
+        QGraphicsAnchorLayoutPrivate::Vertical;
+
+    return QGraphicsAnchorLayoutPrivate::get(l)->lastCalculationUsedSimplex[oo];
+}
+
 void tst_QGraphicsAnchorLayout::simple()
 {
     QGraphicsWidget *w1 = createItem();
@@ -170,10 +179,14 @@ void tst_QGraphicsAnchorLayout::simple()
     l->addAnchors(l, w1, Qt::Vertical);
     l->addAnchors(l, w2, Qt::Vertical);
 
+    QCOMPARE(l->count(), 2);
+
     QGraphicsWidget p;
     p.setLayout(l);
+    p.adjustSize();
 
-    QCOMPARE(l->count(), 2);
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::simple_center()
@@ -213,6 +226,9 @@ void tst_QGraphicsAnchorLayout::simple_center()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize, QSizeF(200, 20));
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
 }
 
@@ -310,6 +326,9 @@ void tst_QGraphicsAnchorLayout::layoutDirection()
 
     QCOMPARE(checkReverseDirection(p), true);
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
     delete view;
 }
@@ -398,6 +417,9 @@ void tst_QGraphicsAnchorLayout::diagonal()
     QCOMPARE(e->geometry(), QRectF(100.0, 200.0, 75.0, 100.0));
     QCOMPARE(p.size(), testA);
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     QCOMPARE(checkReverseDirection(&p), true);
 
     c->setMinimumWidth(300);
@@ -494,6 +516,9 @@ void tst_QGraphicsAnchorLayout::parallel()
     QCOMPARE(e->geometry(), QRectF(375, 400, 175, 100));
     QCOMPARE(f->geometry(), QRectF(550, 500, 200, 100));
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::parallel2()
@@ -539,6 +564,9 @@ void tst_QGraphicsAnchorLayout::parallel2()
 
     p.resize(layoutMaximumSize);
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::snake()
@@ -749,6 +777,9 @@ void tst_QGraphicsAnchorLayout::fairDistribution()
     QCOMPARE(c->geometry(), QRectF(200.0, 200.0, 100.0, 100.0));
     QCOMPARE(d->geometry(), QRectF(0.0, 300.0, 300.0, 100.0));
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
@@ -825,6 +856,9 @@ void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
     QCOMPARE(a->size(), d->size());
     QCOMPARE(e->size().width(), 4 * a->size().width());
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::proportionalPreferred()
@@ -887,6 +921,9 @@ void tst_QGraphicsAnchorLayout::proportionalPreferred()
     QCOMPARE(a->size().width(), 10 * factor);
     QCOMPARE(c->size().width(), 14 * factor);
     QCOMPARE(p.size(), QSizeF(12, 400));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::example()
@@ -970,6 +1007,9 @@ void tst_QGraphicsAnchorLayout::example()
     QCOMPARE(a->size(), e->size());
     QCOMPARE(b->size(), d->size());
     QCOMPARE(f->size(), g->size());
+
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::setSpacing()
@@ -1291,6 +1331,9 @@ void tst_QGraphicsAnchorLayout::sizePolicy()
     QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(100, 100));
     QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(100, 100));
 
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
     delete view;
 }
@@ -1381,6 +1424,9 @@ void tst_QGraphicsAnchorLayout::expandingSequence()
 
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(200));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
@@ -1442,6 +1488,9 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(400));
 
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     // Now we change D to have more "room for growth" from its preferred size
     // to its maximum size. We expect a proportional fair distribution. Note that
     // this seems to not conform with what QGraphicsLinearLayout does.
@@ -1464,6 +1513,9 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QCOMPARE(b->geometry().size(), pref + QSizeF(25, 0));
     QCOMPARE(c->geometry().size(), pref);
     QCOMPARE(d->geometry().size(), pref + QSizeF(50, 0));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::expandingParallel()
-- 
cgit v0.12


From bd47b9215a40ec4d9e290e18ac156f5e0cb5bbd2 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 15:52:11 -0300
Subject: QGAL: avoid having to re-calculate lists of variables

Change the functions solvePreferred() and solveExpanding() to take a
list of variables, so they don't need to calculate them based on the
list of constraints. That way, the trunk variables are calculated only
once.

This commit also reduce the scope of 'sizeHintConstraints' variable
instead of clearing and reusing it.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 50 +++++++++++-------------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |  8 ++--
 2 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index b92d1c3..fa53b66 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1671,9 +1671,7 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
     // of the "trunk" set of constraints and variables.
     // ### does trunk always exist? empty = trunk is the layout left->center->right
     QList<QSimplexConstraint *> trunkConstraints = parts[0];
-    QList<QSimplexConstraint *> sizeHintConstraints;
-    sizeHintConstraints = constraintsFromSizeHints(getVariables(trunkConstraints));
-    trunkConstraints += sizeHintConstraints;
+    QList<AnchorData *> trunkVariables = getVariables(trunkConstraints);
 
     // For minimum and maximum, use the path between the two layout sides as the
     // objective function.
@@ -1695,26 +1693,24 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
         // Solve min and max size hints for trunk
         qreal min, max;
-        feasible = solveMinMax(trunkConstraints, trunkPath, &min, &max);
+
+        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(trunkVariables);
+        QList<QSimplexConstraint *> allTrunkConstraints = trunkConstraints + sizeHintConstraints;
+
+        feasible = solveMinMax(allTrunkConstraints, trunkPath, &min, &max);
 
         if (feasible) {
             // Solve for preferred. The objective function is calculated from the constraints
             // and variables internally.
-            solvePreferred(trunkConstraints);
-
-            // remove sizeHintConstraints from trunkConstraints
-            trunkConstraints = parts[0];
+            solvePreferred(allTrunkConstraints, trunkVariables);
 
             // Solve for expanding. The objective function and the constraints from items
-            // are calculated internally.
-            solveExpanding(trunkConstraints);
+            // are calculated internally. Note that we don't include the sizeHintConstraints, since
+            // they have a different logic for solveExpanding().
+            solveExpanding(trunkConstraints, trunkVariables);
 
             // Propagate the new sizes down the simplified graph, ie. tell the
             // group anchors to set their children anchors sizes.
-
-            // ### we calculated variables already a few times, can't we reuse that?
-            QList<AnchorData *> trunkVariables = getVariables(trunkConstraints);
-
             for (int i = 0; i < trunkVariables.count(); ++i)
                 trunkVariables.at(i)->updateChildrenSizes();
 
@@ -1736,6 +1732,9 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             sizeHints[orientation][Qt::MaximumSize] = max;
             sizeAtExpanding[orientation] = expanding;
         }
+
+        qDeleteAll(sizeHintConstraints);
+
     } else {
 #if 0
         qDebug("Simplex NOT used for trunk of %s",
@@ -1766,10 +1765,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         sizeAtExpanding[orientation] = ad->sizeAtExpanding;
     }
 
-    // Delete the constraints, we won't use them anymore.
-    qDeleteAll(sizeHintConstraints);
-    sizeHintConstraints.clear();
-
     // For the other parts that not the trunk, solve only for the preferred size
     // that is the size they will remain at, since they are not stretched by the
     // layout.
@@ -1781,9 +1776,9 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             QList<AnchorData *> partVariables = getVariables(partConstraints);
             Q_ASSERT(!partVariables.isEmpty());
 
-            sizeHintConstraints = constraintsFromSizeHints(partVariables);
+            QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(partVariables);
             partConstraints += sizeHintConstraints;
-            feasible &= solvePreferred(partConstraints);
+            feasible &= solvePreferred(partConstraints, partVariables);
             if (!feasible)
                 break;
 
@@ -1800,7 +1795,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
             // Delete the constraints, we won't use them anymore.
             qDeleteAll(sizeHintConstraints);
-            sizeHintConstraints.clear();
         }
     }
     graphHasConflicts[orientation] = !feasible;
@@ -2312,7 +2306,7 @@ void QGraphicsAnchorLayoutPrivate::interpolateSequentialEdges(
         interpolateEdge(prev, data->m_edges.last(), orientation);
 }
 
-bool QGraphicsAnchorLayoutPrivate::solveMinMax(QList<QSimplexConstraint *> constraints,
+bool QGraphicsAnchorLayoutPrivate::solveMinMax(const QList<QSimplexConstraint *> &constraints,
                                                GraphPath path, qreal *min, qreal *max)
 {
     QSimplex simplex;
@@ -2353,9 +2347,9 @@ bool QGraphicsAnchorLayoutPrivate::solveMinMax(QList<QSimplexConstraint *> const
     return feasible;
 }
 
-bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> constraints)
+bool QGraphicsAnchorLayoutPrivate::solvePreferred(const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
 {
-    QList<AnchorData *> variables = getVariables(constraints);
     QList<QSimplexConstraint *> preferredConstraints;
     QList<QSimplexVariable *> preferredVariables;
     QSimplexConstraint objective;
@@ -2378,7 +2372,7 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
     //      A + A_shrinker - A_grower = A_pref
     //
     for (int i = 0; i < variables.size(); ++i) {
-        AnchorData *ad = static_cast<AnchorData *>(variables[i]);
+        AnchorData *ad = variables[i];
         if (ad->skipInPreferred)
             continue;
 
@@ -2409,7 +2403,7 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
 
         // Save sizeAtPreferred results
         for (int i = 0; i < variables.size(); ++i) {
-            AnchorData *ad = static_cast<AnchorData *>(variables[i]);
+            AnchorData *ad = variables[i];
             ad->sizeAtPreferred = ad->result;
         }
 
@@ -2470,9 +2464,9 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
           expanding ones will shrink. Only after non-expanding anchors have
           shrinked all the way, the expanding anchors will start to shrink too.
 */
-void QGraphicsAnchorLayoutPrivate::solveExpanding(QList<QSimplexConstraint *> constraints)
+void QGraphicsAnchorLayoutPrivate::solveExpanding(const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
 {
-    QList<AnchorData *> variables = getVariables(constraints);
     QList<QSimplexConstraint *> itemConstraints;
     QSimplexConstraint *objective = new QSimplexConstraint;
     bool hasExpanding = false;
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 7d38e40..474055a 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -471,10 +471,12 @@ public:
                                   Orientation orientation);
 
     // Linear Programming solver methods
-    bool solveMinMax(QList<QSimplexConstraint *> constraints,
+    bool solveMinMax(const QList<QSimplexConstraint *> &constraints,
                      GraphPath path, qreal *min, qreal *max);
-    bool solvePreferred(QList<QSimplexConstraint *> constraints);
-    void solveExpanding(QList<QSimplexConstraint *> constraints);
+    bool solvePreferred(const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
+    void solveExpanding(const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
     bool hasConflicts() const;
 
 #ifdef QT_DEBUG
-- 
cgit v0.12


From a9b1d44fdc9fac0be0016114afcad56e9d372c26 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 16:55:42 -0300
Subject: QGAL: update the sizes of all anchors instead of doing it separatedly

After calculations, update the size of all anchors in the simplified
graph. Those updates were happening locally after each calculation
(trunk and semifloats), however some anchors that were not involved in
simplex calculation were missing.

One concrete consequence of the previous behaviour is that semifloat
parts that were simplified into just one anchor, didn't have the chance
to set their sizeAt* values.  One consequence of the new behaviour is
one more test passing.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp   | 28 +++++++++++++++-------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h     |  1 +
 .../tst_qgraphicsanchorlayout1.cpp                 |  2 --
 3 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index fa53b66..017ddbf 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1709,11 +1709,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             // they have a different logic for solveExpanding().
             solveExpanding(trunkConstraints, trunkVariables);
 
-            // Propagate the new sizes down the simplified graph, ie. tell the
-            // group anchors to set their children anchors sizes.
-            for (int i = 0; i < trunkVariables.count(); ++i)
-                trunkVariables.at(i)->updateChildrenSizes();
-
             // Calculate and set the preferred and expanding sizes for the layout,
             // from the edge sizes that were calculated above.
             qreal pref(0.0);
@@ -1756,9 +1751,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         ad->sizeAtExpanding = ad->expSize;
         ad->sizeAtMaximum = ad->maxSize;
 
-        // Propagate
-        ad->updateChildrenSizes();
-
         sizeHints[orientation][Qt::MinimumSize] = ad->sizeAtMinimum;
         sizeHints[orientation][Qt::PreferredSize] = ad->sizeAtPreferred;
         sizeHints[orientation][Qt::MaximumSize] = ad->sizeAtMaximum;
@@ -1790,13 +1782,17 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                 ad->sizeAtMinimum = ad->sizeAtPreferred;
                 ad->sizeAtExpanding = ad->sizeAtPreferred;
                 ad->sizeAtMaximum = ad->sizeAtPreferred;
-                ad->updateChildrenSizes();
             }
 
             // Delete the constraints, we won't use them anymore.
             qDeleteAll(sizeHintConstraints);
         }
     }
+
+    // Propagate the new sizes down the simplified graph, ie. tell the
+    // group anchors to set their children anchors sizes.
+    updateAnchorSizes(orientation);
+
     graphHasConflicts[orientation] = !feasible;
 
     // Clean up our data structures. They are not needed anymore since
@@ -1907,6 +1903,20 @@ void QGraphicsAnchorLayoutPrivate::constraintsFromPaths(Orientation orientation)
 
 /*!
   \internal
+*/
+void QGraphicsAnchorLayoutPrivate::updateAnchorSizes(Orientation orientation)
+{
+    Graph<AnchorVertex, AnchorData> &g = graph[orientation];
+    const QList<QPair<AnchorVertex *, AnchorVertex *> > &vertices = g.connections();
+
+    for (int i = 0; i < vertices.count(); ++i) {
+        AnchorData *ad = g.edgeData(vertices.at(i).first, vertices.at(i).second);
+        ad->updateChildrenSizes();
+    }
+}
+
+/*!
+  \internal
 
   Create LP constraints for each anchor based on its minimum and maximum
   sizes, as specified in its size hints
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 474055a..940f143 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -441,6 +441,7 @@ public:
     void setAnchorSizeHintsFromItems(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
+    void updateAnchorSizes(Orientation orientation);
     QList<QSimplexConstraint *> constraintsFromSizeHints(const QList<AnchorData *> &anchors);
     QList<QList<QSimplexConstraint *> > getGraphParts(Orientation orientation);
     void identifyNonFloatItems(QSet<AnchorData *> visited, Orientation orientation);
diff --git a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
index 148b2c8..755d866 100644
--- a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
+++ b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
@@ -1711,8 +1711,6 @@ void tst_QGraphicsAnchorLayout1::testBasicLayout()
 
     // Validate
     for (int i = 0; i < result.count(); ++i) {
-        if (i == 1)
-            QEXPECT_FAIL("Two, mixed", "Works with simplification disabled.", Continue);
         const BasicLayoutTestResult item = result[i];
         QCOMPARE(widgets[item.index]->geometry(), item.rect);
     }
-- 
cgit v0.12


From cebaf35e3d79a7cde84a9ef5b0023e841075d5c1 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 20:09:21 -0300
Subject: QGAL: refactor calculateGraphs() method

Create calculateTrunk() and calculateNonTrunk() methods, that
calculate sizes for anchors in different parts of the simplified graph
(using simplex when needed).

Also fixes a minor leak when the nontrunk part is non-feasible. The
old code left the loop leaving the contents of 'sizeHintConstraints'
not allocated.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 161 ++++++++++++-----------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |   7 +
 2 files changed, 93 insertions(+), 75 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 017ddbf..1e9b579 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1600,7 +1600,8 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs()
     calculateGraphCacheDirty = 0;
 }
 
-// ### remove me:
+// ### Maybe getGraphParts could return the variables when traversing, at least
+// for trunk...
 QList<AnchorData *> getVariables(QList<QSimplexConstraint *> constraints)
 {
     QSet<AnchorData *> variableSet;
@@ -1664,8 +1665,7 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
     //  2) The floating or semi-floating anchors (items) that are those which
     //     are connected to only one (or none) of the layout sides, thus are not
     //     influenced by the layout size.
-    QList<QList<QSimplexConstraint *> > parts;
-    parts = getGraphParts(orientation);
+    QList<QList<QSimplexConstraint *> > parts = getGraphParts(orientation);
 
     // Now run the simplex solver to calculate Minimum, Preferred and Maximum sizes
     // of the "trunk" set of constraints and variables.
@@ -1675,49 +1675,82 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
     // For minimum and maximum, use the path between the two layout sides as the
     // objective function.
-
-    // Retrieve that path
     AnchorVertex *v = internalVertex(q, pickEdge(Qt::AnchorRight, orientation));
     GraphPath trunkPath = graphPaths[orientation].value(v);
 
+    bool feasible = calculateTrunk(orientation, trunkPath, trunkConstraints, trunkVariables);
+
+    // For the other parts that not the trunk, solve only for the preferred size
+    // that is the size they will remain at, since they are not stretched by the
+    // layout.
+
+    // Skipping the first (trunk)
+    for (int i = 1; i < parts.count(); ++i) {
+        if (!feasible)
+            break;
+
+        QList<QSimplexConstraint *> partConstraints = parts[i];
+        QList<AnchorData *> partVariables = getVariables(partConstraints);
+        Q_ASSERT(!partVariables.isEmpty());
+        feasible &= calculateNonTrunk(partConstraints, partVariables);
+    }
+
+    // Propagate the new sizes down the simplified graph, ie. tell the
+    // group anchors to set their children anchors sizes.
+    updateAnchorSizes(orientation);
+
+    graphHasConflicts[orientation] = !feasible;
+
+    // Clean up our data structures. They are not needed anymore since
+    // distribution uses just interpolation.
+    qDeleteAll(constraints[orientation]);
+    constraints[orientation].clear();
+    graphPaths[orientation].clear(); // ###
+}
+
+/*!
+    \internal
+
+    Calculate the sizes for all anchors which are part of the trunk. This works
+    on top of a (possibly) simplified graph.
+*/
+bool QGraphicsAnchorLayoutPrivate::calculateTrunk(Orientation orientation, const GraphPath &path,
+                                                  const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
+{
     bool feasible = true;
-    if (!trunkConstraints.isEmpty()) {
-#if 0
-        qDebug("Simplex used for trunk of %s",
-               orientation == Horizontal ? "Horizontal" : "Vertical");
-#endif
+    bool needsSimplex = !constraints.isEmpty();
 
-#ifdef QT_DEBUG
-        lastCalculationUsedSimplex[orientation] = true;
+#if 0
+    qDebug("Simplex %s for trunk of %s", needsSimplex ? "used" : "NOT used",
+           orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
-        // Solve min and max size hints for trunk
-        qreal min, max;
+    if (needsSimplex) {
 
-        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(trunkVariables);
-        QList<QSimplexConstraint *> allTrunkConstraints = trunkConstraints + sizeHintConstraints;
+        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(variables);
+        QList<QSimplexConstraint *> allConstraints = constraints + sizeHintConstraints;
 
-        feasible = solveMinMax(allTrunkConstraints, trunkPath, &min, &max);
+        // Solve min and max size hints
+        qreal min, max;
+        feasible = solveMinMax(allConstraints, path, &min, &max);
 
         if (feasible) {
-            // Solve for preferred. The objective function is calculated from the constraints
-            // and variables internally.
-            solvePreferred(allTrunkConstraints, trunkVariables);
+            solvePreferred(allConstraints, variables);
 
-            // Solve for expanding. The objective function and the constraints from items
-            // are calculated internally. Note that we don't include the sizeHintConstraints, since
-            // they have a different logic for solveExpanding().
-            solveExpanding(trunkConstraints, trunkVariables);
+            // Note that we don't include the sizeHintConstraints, since they
+            // have a different logic for solveExpanding().
+            solveExpanding(constraints, variables);
 
             // Calculate and set the preferred and expanding sizes for the layout,
             // from the edge sizes that were calculated above.
             qreal pref(0.0);
             qreal expanding(0.0);
-            foreach (const AnchorData *ad, trunkPath.positives) {
+            foreach (const AnchorData *ad, path.positives) {
                 pref += ad->sizeAtPreferred;
                 expanding += ad->sizeAtExpanding;
             }
-            foreach (const AnchorData *ad, trunkPath.negatives) {
+            foreach (const AnchorData *ad, path.negatives) {
                 pref -= ad->sizeAtPreferred;
                 expanding -= ad->sizeAtExpanding;
             }
@@ -1731,21 +1764,12 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         qDeleteAll(sizeHintConstraints);
 
     } else {
-#if 0
-        qDebug("Simplex NOT used for trunk of %s",
-               orientation == Horizontal ? "Horizontal" : "Vertical");
-#endif
-
-#ifdef QT_DEBUG
-        lastCalculationUsedSimplex[orientation] = false;
-#endif
-
         // No Simplex is necessary because the path was simplified all the way to a single
         // anchor.
-        Q_ASSERT(trunkPath.positives.count() == 1);
-        Q_ASSERT(trunkPath.negatives.count() == 0);
+        Q_ASSERT(path.positives.count() == 1);
+        Q_ASSERT(path.negatives.count() == 0);
 
-        AnchorData *ad = trunkPath.positives.toList()[0];
+        AnchorData *ad = path.positives.toList()[0];
         ad->sizeAtMinimum = ad->minSize;
         ad->sizeAtPreferred = ad->prefSize;
         ad->sizeAtExpanding = ad->expSize;
@@ -1757,49 +1781,36 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         sizeAtExpanding[orientation] = ad->sizeAtExpanding;
     }
 
-    // For the other parts that not the trunk, solve only for the preferred size
-    // that is the size they will remain at, since they are not stretched by the
-    // layout.
+#ifdef QT_DEBUG
+    lastCalculationUsedSimplex[orientation] = needsSimplex;
+#endif
 
-    // Solve the other only for preferred, skip trunk
-    if (feasible) {
-        for (int i = 1; i < parts.count(); ++i) {
-            QList<QSimplexConstraint *> partConstraints = parts[i];
-            QList<AnchorData *> partVariables = getVariables(partConstraints);
-            Q_ASSERT(!partVariables.isEmpty());
-
-            QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(partVariables);
-            partConstraints += sizeHintConstraints;
-            feasible &= solvePreferred(partConstraints, partVariables);
-            if (!feasible)
-                break;
+    return feasible;
+}
 
-            // Propagate size at preferred to other sizes. Semi-floats
-            // always will be in their sizeAtPreferred.
-            for (int j = 0; j < partVariables.count(); ++j) {
-                AnchorData *ad = partVariables[j];
-                Q_ASSERT(ad);
-                ad->sizeAtMinimum = ad->sizeAtPreferred;
-                ad->sizeAtExpanding = ad->sizeAtPreferred;
-                ad->sizeAtMaximum = ad->sizeAtPreferred;
-            }
+/*!
+    \internal
+*/
+bool QGraphicsAnchorLayoutPrivate::calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,
+                                                     const QList<AnchorData *> &variables)
+{
+    QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(variables);
+    bool feasible = solvePreferred(constraints + sizeHintConstraints, variables);
 
-            // Delete the constraints, we won't use them anymore.
-            qDeleteAll(sizeHintConstraints);
+    if (feasible) {
+        // Propagate size at preferred to other sizes. Semi-floats always will be
+        // in their sizeAtPreferred.
+        for (int j = 0; j < variables.count(); ++j) {
+            AnchorData *ad = variables[j];
+            Q_ASSERT(ad);
+            ad->sizeAtMinimum = ad->sizeAtPreferred;
+            ad->sizeAtExpanding = ad->sizeAtPreferred;
+            ad->sizeAtMaximum = ad->sizeAtPreferred;
         }
     }
 
-    // Propagate the new sizes down the simplified graph, ie. tell the
-    // group anchors to set their children anchors sizes.
-    updateAnchorSizes(orientation);
-
-    graphHasConflicts[orientation] = !feasible;
-
-    // Clean up our data structures. They are not needed anymore since
-    // distribution uses just interpolation.
-    qDeleteAll(constraints[orientation]);
-    constraints[orientation].clear();
-    graphPaths[orientation].clear(); // ###
+    qDeleteAll(sizeHintConstraints);
+    return feasible;
 }
 
 /*!
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 940f143..2ced72d 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -438,6 +438,13 @@ public:
 
     void calculateGraphs();
     void calculateGraphs(Orientation orientation);
+
+    bool calculateTrunk(Orientation orientation, const GraphPath &trunkPath,
+                        const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
+    bool calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,
+                           const QList<AnchorData *> &variables);
+
     void setAnchorSizeHintsFromItems(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
-- 
cgit v0.12


From 9ea66fb4d1e1ad36bcd1a0e4b7e7de348273e8ff Mon Sep 17 00:00:00 2001
From: Olivier Goffart <ogoffart@trolltech.com>
Date: Thu, 15 Oct 2009 10:34:34 +0200
Subject: Spreadsheet demo: fix the footer color.

One of the footer cell lost his gray color in commit 7c12258485db8d

Task-number: QTBUG-4821
Reviewed-by: Jan-Arve
---
 demos/spreadsheet/spreadsheet.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/demos/spreadsheet/spreadsheet.cpp b/demos/spreadsheet/spreadsheet.cpp
index 7f057a2..00045c6 100644
--- a/demos/spreadsheet/spreadsheet.cpp
+++ b/demos/spreadsheet/spreadsheet.cpp
@@ -523,6 +523,7 @@ void SpreadSheet::setupContents()
     table->setItem(8, 2, new SpreadSheetItem("1240"));
 
     table->setItem(9, 2, new SpreadSheetItem());
+    table->item(9, 2)->setBackgroundColor(Qt::lightGray);
 
     // column 3
     table->setItem(0, 3, new SpreadSheetItem("Currency"));
-- 
cgit v0.12


From 2055fe9eb514b79a34a0c216164cd1a11561be4f Mon Sep 17 00:00:00 2001
From: Olivier Goffart <ogoffart@trolltech.com>
Date: Thu, 15 Oct 2009 11:44:01 +0200
Subject: Stabilize QLineEdit test on X11

---
 tests/auto/qlineedit/tst_qlineedit.cpp | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/tests/auto/qlineedit/tst_qlineedit.cpp b/tests/auto/qlineedit/tst_qlineedit.cpp
index 8368114..c676959 100644
--- a/tests/auto/qlineedit/tst_qlineedit.cpp
+++ b/tests/auto/qlineedit/tst_qlineedit.cpp
@@ -3304,41 +3304,45 @@ void tst_QLineEdit::task174640_editingFinished()
     layout->addWidget(le2);
 
     mw.show();
-    QTest::qWait(200);
+    QApplication::setActiveWindow(&mw);
     mw.activateWindow();
+    QTest::qWaitForWindowShown(&mw);
 
     QSignalSpy editingFinishedSpy(le1, SIGNAL(editingFinished()));
 
     le1->setFocus();
-    QTest::qWait(200);
-    QVERIFY(le1->hasFocus());
+    QTest::qWait(20);
+    QTRY_VERIFY(le1->hasFocus());
     QCOMPARE(editingFinishedSpy.count(), 0);
 
     le2->setFocus();
-    QTest::qWait(200);
-    QVERIFY(le2->hasFocus());
+    QTest::qWait(20);
+    QTRY_VERIFY(le2->hasFocus());
     QCOMPARE(editingFinishedSpy.count(), 1);
     editingFinishedSpy.clear();
 
     le1->setFocus();
-    QTest::qWait(200);
-    QVERIFY(le1->hasFocus());
+    QTest::qWait(20);
+    QTRY_VERIFY(le1->hasFocus());
 
     QMenu *testMenu1 = new QMenu(le1);
     testMenu1->addAction("foo");
     testMenu1->addAction("bar");
     testMenu1->show();
-    QTest::qWait(200);
+    QTest::qWaitForWindowShown(testMenu1);
+    QTest::qWait(20);
     mw.activateWindow();
+
     delete testMenu1;
     QCOMPARE(editingFinishedSpy.count(), 0);
-    QVERIFY(le1->hasFocus());
+    QTRY_VERIFY(le1->hasFocus());
 
     QMenu *testMenu2 = new QMenu(le2);
     testMenu2->addAction("foo2");
     testMenu2->addAction("bar2");
     testMenu2->show();
-    QTest::qWait(200);
+    QTest::qWaitForWindowShown(testMenu2);
+    QTest::qWait(20);
     mw.activateWindow();
     delete testMenu2;
     QCOMPARE(editingFinishedSpy.count(), 1);
-- 
cgit v0.12


From d5be015ddf268f195568d313dc2c5491a6a2db93 Mon Sep 17 00:00:00 2001
From: Olivier Goffart <ogoffart@trolltech.com>
Date: Thu, 15 Oct 2009 13:55:32 +0200
Subject: Stabilize test on x11

---
 tests/auto/qgraphicsproxywidget/tst_qgraphicsproxywidget.cpp | 7 ++++---
 tests/auto/qwidget/tst_qwidget.cpp                           | 8 ++++----
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/tests/auto/qgraphicsproxywidget/tst_qgraphicsproxywidget.cpp b/tests/auto/qgraphicsproxywidget/tst_qgraphicsproxywidget.cpp
index 013a028..2426ce9 100644
--- a/tests/auto/qgraphicsproxywidget/tst_qgraphicsproxywidget.cpp
+++ b/tests/auto/qgraphicsproxywidget/tst_qgraphicsproxywidget.cpp
@@ -1287,6 +1287,7 @@ void tst_QGraphicsProxyWidget::paintEvent()
     QGraphicsView view(&scene);
     view.show();
     QTest::qWaitForWindowShown(&view);
+    QTest::qWait(70);
 
     SubQGraphicsProxyWidget proxy;
 
@@ -1297,14 +1298,14 @@ void tst_QGraphicsProxyWidget::paintEvent()
     w->show();
     QTest::qWaitForWindowShown(w);
     QApplication::processEvents();
-    QTest::qWait(50);
+    QTest::qWait(100);
     proxy.setWidget(w);
     scene.addItem(&proxy);
 
     //make sure we flush all the paint events
     QTest::qWait(70);
     QTRY_VERIFY(proxy.paintCount > 1);
-    QTest::qWait(70);
+    QTest::qWait(110);
     proxy.paintCount = 0;
 
     w->update();
@@ -2705,7 +2706,7 @@ void tst_QGraphicsProxyWidget::windowOpacity()
     view.show();
     QTest::qWaitForWindowShown(&view);
     QApplication::sendPostedEvents();
-    QTest::qWait(50);
+    QTest::qWait(150);
 
     qRegisterMetaType<QList<QRectF> >("QList<QRectF>");
     QSignalSpy signalSpy(&scene, SIGNAL(changed(const QList<QRectF> &)));
diff --git a/tests/auto/qwidget/tst_qwidget.cpp b/tests/auto/qwidget/tst_qwidget.cpp
index c000a12..daeee3d 100644
--- a/tests/auto/qwidget/tst_qwidget.cpp
+++ b/tests/auto/qwidget/tst_qwidget.cpp
@@ -7459,11 +7459,11 @@ void tst_QWidget::updateWhileMinimized()
     QTest::qWaitForWindowShown(&widget);
     QApplication::processEvents();
     QTRY_VERIFY(widget.numPaintEvents > 0);
-    QTest::qWait(50);
+    QTest::qWait(150);
 
     // Minimize window.
     widget.showMinimized();
-    QTest::qWait(70);
+    QTest::qWait(110);
 
     widget.reset();
 
@@ -8164,7 +8164,7 @@ public:
 
         static bool firstTime = true;
         if (firstTime)
-            QTimer::singleShot(150, this, SLOT(resizeMe()));
+            QTimer::singleShot(250, this, SLOT(resizeMe()));
 
         firstTime = false;
     }
@@ -8181,7 +8181,7 @@ void tst_QWidget::moveInResizeEvent()
     testWidget.setGeometry(50, 50, 200, 200);
     testWidget.show();
     QTest::qWaitForWindowShown(&testWidget);
-    QTest::qWait(160);
+    QTest::qWait(300);
 
     QRect expectedGeometry(100,100, 100, 100);
     QTRY_COMPARE(testWidget.geometry(), expectedGeometry);
-- 
cgit v0.12


From 038434b66a473c08e78dc40376c5890dd1af938f Mon Sep 17 00:00:00 2001
From: Gabriel de Dietrich <gabriel.dietrich-de@nokia.com>
Date: Thu, 15 Oct 2009 14:14:19 +0200
Subject: Fixed updating problems QListView with IconMode

The updated rectangle coordinates didn't use the viewport offsets.

Reviewed-by: Olivier
Task-number: QTBUG-4819
---
 src/gui/itemviews/qlistview.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gui/itemviews/qlistview.cpp b/src/gui/itemviews/qlistview.cpp
index 9b0b00f..243f542 100644
--- a/src/gui/itemviews/qlistview.cpp
+++ b/src/gui/itemviews/qlistview.cpp
@@ -2490,7 +2490,7 @@ bool QIconModeViewBase::filterDropEvent(QDropEvent *e)
     for (int i = 0; i < indexes.count(); ++i) {
         QModelIndex index = indexes.at(i);
         QRect rect = dd->rectForIndex(index);
-        viewport()->update(mapToViewport(rect));
+        viewport()->update(dd->mapToViewport(rect, false));
         QPoint dest = rect.topLeft() + delta;
         if (qq->isRightToLeft())
             dest.setX(dd->flipX(dest.x()) - rect.width());
-- 
cgit v0.12


From 2eee73e843ba7b4c6e83bd6bfaa08994520c417d Mon Sep 17 00:00:00 2001
From: Olivier Goffart <ogoffart@trolltech.com>
Date: Thu, 15 Oct 2009 15:45:14 +0200
Subject: Compilation of the QGraphicsAnchorLayout test on 64bit

+ stabilize the linear layout test
---
 tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp | 2 +-
 tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp   | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
index 148b2c8..e69a718 100644
--- a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
+++ b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
@@ -435,7 +435,7 @@ void tst_QGraphicsAnchorLayout1::testAddAndRemoveAnchor()
     layout->removeAnchor(layout, Qt::AnchorLeft, widget1, Qt::AnchorLeft);
 
     QCOMPARE( layout->count(), 4 );
-    QCOMPARE( (int)widget1->parentLayoutItem(), 0 );
+    QVERIFY( !widget1->parentLayoutItem() );
 
     // test that item is not removed from layout if other anchors remain set
     layout->setAnchor(widget2, Qt::AnchorLeft, widget3, Qt::AnchorRight, 10);
diff --git a/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp b/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
index 4f28df4..8e7bb45 100644
--- a/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
+++ b/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
@@ -146,7 +146,7 @@ void tst_QGraphicsLinearLayout::initTestCase()
     // since the style will influence the results, we have to ensure
     // that the tests are run using the same style on all platforms
 #ifdef Q_WS_S60
-    QApplication::setStyle(new QWindowsStyle);    
+    QApplication::setStyle(new QWindowsStyle);
 #else
     QApplication::setStyle(new QPlastiqueStyle);
 #endif
@@ -332,6 +332,7 @@ void tst_QGraphicsLinearLayout::alignment()
         widget->resize(newSize);
     view.show();
     widget->show();
+    QTest::qWaitForWindowShown(&view);
     QApplication::processEvents();
 
     int x = 0;
-- 
cgit v0.12


From f81a563c74eece173a0cf1d6c3243604c0db0a5b Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 10:44:08 -0300
Subject: QGraphicsAnchorLayout: Ensure spacing is not negative

Currently we do not support negative-sized anchors in the graph,
instead we invert such anchors and make their value positive.

We consider changing this sometime in the future but until then,
spacing must be non-negative at all times.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout.cpp   | 26 ++++++++++++++++++++++++
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp |  7 +++++++
 2 files changed, 33 insertions(+)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout.cpp b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
index ffbb67c..9f4a19b 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
@@ -306,6 +306,13 @@ void QGraphicsAnchorLayout::addAnchors(QGraphicsLayoutItem *firstItem,
 void QGraphicsAnchorLayout::setHorizontalSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### We don't support negative spacing yet
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[0] = spacing;
     invalidate();
 }
@@ -318,6 +325,13 @@ void QGraphicsAnchorLayout::setHorizontalSpacing(qreal spacing)
 void QGraphicsAnchorLayout::setVerticalSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### We don't support negative spacing yet
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[1] = spacing;
     invalidate();
 }
@@ -327,11 +341,23 @@ void QGraphicsAnchorLayout::setVerticalSpacing(qreal spacing)
 
     If an item is anchored with no spacing associated with the anchor, it will use the default
     spacing.
+
+    Currently QGraphicsAnchorLayout does not support negative default spacings.
+
     \sa setHorizontalSpacing(), setVerticalSpacing()
 */
 void QGraphicsAnchorLayout::setSpacing(qreal spacing)
 {
     Q_D(QGraphicsAnchorLayout);
+
+    // ### Currently we do not support negative anchors inside the graph.
+    // To avoid those being created by a negative spacing, we must
+    // make this test.
+    if (spacing < 0) {
+        spacing = 0;
+        qWarning() << "QGraphicsAnchorLayout does not support negative spacing.";
+    }
+
     d->spacings[0] = d->spacings[1] = spacing;
     invalidate();
 }
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index f9b5c8c..1cbea8e 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1550,6 +1550,13 @@ qreal QGraphicsAnchorLayoutPrivate::effectiveSpacing(Orientation orientation) co
             }
         }
     }
+
+    // ### Currently we do not support negative anchors inside the graph.
+    // To avoid those being created by a negative style spacing, we must
+    // make this test.
+    if (s < 0)
+        s = 0;
+
     return s;
 }
 
-- 
cgit v0.12


From 80ffc2fa1766aa8009a30de495fc11ab6690bd87 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 14:30:57 -0300
Subject: QGraphicsAnchorLayout: Add test for 'infinite' max size widgets

With four items anchored side by side, each of them being allowed
to grow to QWIDGETSIZE_MAX, we have a situation of fair distribution
because the layout itself can grow only to QWIDGETSIZE_MAX (and not
four times this amount).

This test identified an error on the expanding distribution logic.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 .../tst_qgraphicsanchorlayout.cpp                  | 49 ++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index 286ea2d..cf4e9b8 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -73,6 +73,7 @@ private slots:
     void expandingSequenceFairDistribution();
     void expandingParallel();
     void floatConflict();
+    void infiniteMaxSizes();
 };
 
 class RectWidget : public QGraphicsWidget
@@ -1585,5 +1586,53 @@ void tst_QGraphicsAnchorLayout::floatConflict()
     delete p;
 }
 
+void tst_QGraphicsAnchorLayout::infiniteMaxSizes()
+{
+    QGraphicsAnchorLayout *l = new QGraphicsAnchorLayout;
+    l->setContentsMargins(0, 0, 0, 0);
+    l->setSpacing(0);
+
+    QSizeF min(10, 10);
+    QSizeF pref(50, 10);
+    QSizeF max(QWIDGETSIZE_MAX, 10);
+
+    QGraphicsWidget *a = createItem(min, pref, max, "a");
+    QGraphicsWidget *b = createItem(min, pref, max, "b");
+    QGraphicsWidget *c = createItem(min, pref, max, "c");
+    QGraphicsWidget *d = createItem(min, pref, max, "d");
+
+    //<!-- Trunk -->
+    setAnchor(l, l, Qt::AnchorLeft, a, Qt::AnchorLeft, 0);
+    setAnchor(l, a, Qt::AnchorRight, b, Qt::AnchorLeft, 0);
+    setAnchor(l, b, Qt::AnchorRight, c, Qt::AnchorLeft, 0);
+    setAnchor(l, c, Qt::AnchorRight, d, Qt::AnchorLeft, 0);
+    setAnchor(l, d, Qt::AnchorRight, l, Qt::AnchorRight, 0);
+
+    a->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
+    c->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
+
+    QGraphicsWidget p;
+    p.setLayout(l);
+
+    p.resize(200, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, 50, 10));
+    QCOMPARE(b->geometry(), QRectF(50, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(100, 0, 50, 10));
+    QCOMPARE(d->geometry(), QRectF(150, 0, 50, 10));
+
+    p.resize(1000, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, 450, 10));
+    QCOMPARE(b->geometry(), QRectF(450, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(500, 0, 450, 10));
+    QCOMPARE(d->geometry(), QRectF(950, 0, 50, 10));
+
+    qreal expMaxSize = (QWIDGETSIZE_MAX - 100.0) / 2;
+    p.resize(QWIDGETSIZE_MAX, 10);
+    QCOMPARE(a->geometry(), QRectF(0, 0, expMaxSize, 10));
+    QCOMPARE(b->geometry(), QRectF(expMaxSize, 0, 50, 10));
+    QCOMPARE(c->geometry(), QRectF(expMaxSize + 50, 0, expMaxSize, 10));
+    QCOMPARE(d->geometry(), QRectF(QWIDGETSIZE_MAX - 50, 0, 50, 10));
+}
+
 QTEST_MAIN(tst_QGraphicsAnchorLayout)
 #include "tst_qgraphicsanchorlayout.moc"
-- 
cgit v0.12


From 70bfdcee2e09cb491a5dbcc37caaf17076893339 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 8 Oct 2009 15:47:42 -0300
Subject: QGraphicsAnchorLayout: Fix sequential anchor distribution w/
 expanding sizes

After the addition of expanding SizePolicy, the distribution of sequential
anchors became wrong.

We must now account for three intervals of distribution instead of only two.
This commit also unifies the logic used by the sequential group anchor and
the edge interpolator.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 162 +++++++++++------------
 1 file changed, 76 insertions(+), 86 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 1cbea8e..ff42cb5 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -250,44 +250,61 @@ void ParallelAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
      0 is at Preferred
      1 is at Maximum
 */
-static qreal getFactor(qreal value, qreal min, qreal pref, qreal max)
-{
-    // ### Maybe remove some of the assertions? (since outside is asserting us)
-    Q_ASSERT(value > min || qFuzzyCompare(value, min));
-    Q_ASSERT(value < max || qFuzzyCompare(value, max));
-
-    if (qFuzzyCompare(value, min)) {
-        return -1.0;
-    } else if (qFuzzyCompare(value, pref)) {
-        return 0.0;
-    } else if (qFuzzyCompare(value, max)) {
-        return 1.0;
-    } else if (value < pref) {
-        // Since value < pref and value != pref and min <= value,
-        // we can assert that min < pref.
-        Q_ASSERT(min < pref);
-        return (value - min) / (pref - min) - 1;
+static QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> getFactor(qreal value, qreal min,
+                                                                      qreal pref, qreal exp,
+                                                                      qreal max)
+{
+    QGraphicsAnchorLayoutPrivate::Interval interval;
+    qreal lower;
+    qreal upper;
+
+    if (value < pref) {
+        interval = QGraphicsAnchorLayoutPrivate::MinToPreferred;
+        lower = min;
+        upper = pref;
+    } else if (value < exp) {
+        interval = QGraphicsAnchorLayoutPrivate::PreferredToExpanding;
+        lower = pref;
+        upper = exp;
     } else {
-        // Since value > pref and value != pref and max >= value,
-        // we can assert that max > pref.
-        Q_ASSERT(max > pref);
-        return (value - pref) / (max - pref);
+        interval = QGraphicsAnchorLayoutPrivate::ExpandingToMax;
+        lower = exp;
+        upper = max;
     }
+
+    qreal progress;
+    if (upper == lower) {
+        progress = 0;
+    } else {
+        progress = (value - lower) / (upper - lower);
+    }
+
+    return qMakePair(interval, progress);
 }
 
-static qreal getExpandingFactor(const qreal &expSize, const qreal &sizeAtPreferred,
-                                const qreal &sizeAtExpanding, const qreal &sizeAtMaximum)
+static qreal interpolate(const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> &factor,
+                         qreal min, qreal pref,
+                         qreal exp, qreal max)
 {
-    const qreal lower = qMin(sizeAtPreferred, sizeAtMaximum);
-    const qreal upper = qMax(sizeAtPreferred, sizeAtMaximum);
-    const qreal boundedExpSize = qBound(lower, expSize, upper);
+    qreal lower;
+    qreal upper;
 
-    const qreal bandSize = sizeAtMaximum - boundedExpSize;
-    if (bandSize == 0) {
-        return 0;
-    } else {
-        return (sizeAtExpanding - boundedExpSize) / bandSize;
+    switch (factor.first) {
+    case QGraphicsAnchorLayoutPrivate::MinToPreferred:
+        lower = min;
+        upper = pref;
+        break;
+    case QGraphicsAnchorLayoutPrivate::PreferredToExpanding:
+        lower = pref;
+        upper = exp;
+        break;
+    case QGraphicsAnchorLayoutPrivate::ExpandingToMax:
+        lower = exp;
+        upper = max;
+        break;
     }
+
+    return lower + factor.second * (upper - lower);
 }
 
 void SequentialAnchorData::updateChildrenSizes()
@@ -307,27 +324,22 @@ void SequentialAnchorData::updateChildrenSizes()
     // Band here refers if the value is in the Minimum To Preferred
     // band (the lower band) or the Preferred To Maximum (the upper band).
 
-    const qreal minFactor = getFactor(sizeAtMinimum, minSize, prefSize, maxSize);
-    const qreal prefFactor = getFactor(sizeAtPreferred, minSize, prefSize, maxSize);
-    const qreal maxFactor = getFactor(sizeAtMaximum, minSize, prefSize, maxSize);
-    const qreal expFactor = getExpandingFactor(expSize, sizeAtPreferred, sizeAtExpanding, sizeAtMaximum);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> minFactor =
+        getFactor(sizeAtMinimum, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> prefFactor =
+        getFactor(sizeAtPreferred, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> expFactor =
+        getFactor(sizeAtExpanding, minSize, prefSize, expSize, maxSize);
+    const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> maxFactor =
+        getFactor(sizeAtMaximum, minSize, prefSize, expSize, maxSize);
 
     for (int i = 0; i < m_edges.count(); ++i) {
         AnchorData *e = m_edges.at(i);
 
-        qreal bandSize = minFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtMinimum = e->prefSize + bandSize * minFactor;
-
-        bandSize = prefFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtPreferred = e->prefSize + bandSize * prefFactor;
-
-        bandSize = maxFactor > 0 ? e->maxSize - e->prefSize : e->prefSize - e->minSize;
-        e->sizeAtMaximum = e->prefSize + bandSize * maxFactor;
-
-        const qreal lower = qMin(e->sizeAtPreferred, e->sizeAtMaximum);
-        const qreal upper = qMax(e->sizeAtPreferred, e->sizeAtMaximum);
-        const qreal edgeBoundedExpSize = qBound(lower, e->expSize, upper);
-        e->sizeAtExpanding = edgeBoundedExpSize + expFactor * (e->sizeAtMaximum - edgeBoundedExpSize);
+        e->sizeAtMinimum = interpolate(minFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtPreferred = interpolate(prefFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtExpanding = interpolate(expFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
+        e->sizeAtMaximum = interpolate(maxFactor, e->minSize, e->prefSize, e->expSize, e->maxSize);
 
         e->updateChildrenSizes();
     }
@@ -2167,39 +2179,26 @@ void QGraphicsAnchorLayoutPrivate::calculateVertexPositions(
   \internal
 
   Calculate interpolation parameters based on current Layout Size.
-  Must once before calling "interpolateEdgeSize()" for each edge.
+  Must be called once before calling "interpolateEdgeSize()" for
+  the edges.
 */
 void QGraphicsAnchorLayoutPrivate::setupEdgesInterpolation(
     Orientation orientation)
 {
     Q_Q(QGraphicsAnchorLayout);
-    qreal lower, upper, current;
 
-    if (orientation == Horizontal) {
-        current = q->contentsRect().width();
-    } else {
-        current = q->contentsRect().height();
-    }
+    qreal current;
+    current = (orientation == Horizontal) ? q->contentsRect().width() : q->contentsRect().height();
 
-    if (current < sizeHints[orientation][Qt::PreferredSize]) {
-        interpolationInterval[orientation] = MinToPreferred;
-        lower = sizeHints[orientation][Qt::MinimumSize];
-        upper = sizeHints[orientation][Qt::PreferredSize];
-    } else if (current < sizeAtExpanding[orientation]) {
-        interpolationInterval[orientation] = PreferredToExpanding;
-        lower = sizeHints[orientation][Qt::PreferredSize];
-        upper = sizeAtExpanding[orientation];
-    } else {
-        interpolationInterval[orientation] = ExpandingToMax;
-        lower = sizeAtExpanding[orientation];
-        upper = sizeHints[orientation][Qt::MaximumSize];
-    }
+    QPair<Interval, qreal> result;
+    result = getFactor(current,
+                       sizeHints[orientation][Qt::MinimumSize],
+                       sizeHints[orientation][Qt::PreferredSize],
+                       sizeAtExpanding[orientation],
+                       sizeHints[orientation][Qt::MaximumSize]);
 
-    if (upper == lower) {
-        interpolationProgress[orientation] = 0;
-    } else {
-        interpolationProgress[orientation] = (current - lower) / (upper - lower);
-    }
+    interpolationInterval[orientation] = result.first;
+    interpolationProgress[orientation] = result.second;
 }
 
 /*!
@@ -2226,20 +2225,11 @@ void QGraphicsAnchorLayoutPrivate::interpolateEdge(AnchorVertex *base,
                                                    AnchorData *edge,
                                                    Orientation orientation)
 {
-    qreal lower, upper;
-
-    if (interpolationInterval[orientation] == MinToPreferred) {
-        lower = edge->sizeAtMinimum;
-        upper = edge->sizeAtPreferred;
-    } else if (interpolationInterval[orientation] == PreferredToExpanding) {
-        lower = edge->sizeAtPreferred;
-        upper = edge->sizeAtExpanding;
-    } else {
-        lower = edge->sizeAtExpanding;
-        upper = edge->sizeAtMaximum;
-    }
+    const QPair<Interval, qreal> factor(interpolationInterval[orientation],
+                                        interpolationProgress[orientation]);
 
-    qreal edgeDistance = (interpolationProgress[orientation] * (upper - lower)) + lower;
+    qreal edgeDistance = interpolate(factor, edge->sizeAtMinimum, edge->sizeAtPreferred,
+                                     edge->sizeAtExpanding, edge->sizeAtMaximum);
 
     Q_ASSERT(edge->from == base || edge->to == base);
 
-- 
cgit v0.12


From a0b0e6b086b493aa833596a7d228ca7eb27be47e Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Wed, 7 Oct 2009 19:34:09 -0300
Subject: QGAL: improve dump graph and add helper code

The graph dumper function take a name, and added debug code (that need
to be enabled manually) to generate dumps from the graph before and
after calculation. This is useful to debug simplification.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 14 ++++++++++++--
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |  2 +-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index ff42cb5..f090aa3 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1584,9 +1584,19 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs()
     if (!calculateGraphCacheDirty)
         return;
 
+#if defined(QT_DEBUG) && 0
+    static int count = 0;
+    count++;
+    dumpGraph(QString::fromAscii("%1-before").arg(count));
+#endif
+
     calculateGraphs(Horizontal);
     calculateGraphs(Vertical);
 
+#if defined(QT_DEBUG) && 0
+    dumpGraph(QString::fromAscii("%1-after").arg(count));
+#endif
+
     calculateGraphCacheDirty = 0;
 }
 
@@ -2563,9 +2573,9 @@ bool QGraphicsAnchorLayoutPrivate::hasConflicts() const
 }
 
 #ifdef QT_DEBUG
-void QGraphicsAnchorLayoutPrivate::dumpGraph()
+void QGraphicsAnchorLayoutPrivate::dumpGraph(const QString &name)
 {
-    QFile file(QString::fromAscii("anchorlayout.dot"));
+    QFile file(QString::fromAscii("anchorlayout.%1.dot").arg(name));
     if (!file.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate))
         qWarning("Could not write to %s", file.fileName().toLocal8Bit().constData());
 
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 9ac0e19..9b50661 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -478,7 +478,7 @@ public:
     bool hasConflicts() const;
 
 #ifdef QT_DEBUG
-    void dumpGraph();
+    void dumpGraph(const QString &name = QString());
 #endif
 
 
-- 
cgit v0.12


From 1501429a78d647f922dfdb4432fbfac333143c91 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Wed, 7 Oct 2009 19:41:32 -0300
Subject: QGAL: add a way to test whether simplex was used in a calculation

This is one good way to track whether simplification is doing all its
job or not. However it can only track cases where the graph simplify
to only one anchor. For more complex cases the graph dumps are the way
to go.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp   |  8 ++++
 src/gui/graphicsview/qgraphicsanchorlayout_p.h     |  4 ++
 .../tst_qgraphicsanchorlayout.cpp                  | 54 +++++++++++++++++++++-
 3 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index f090aa3..b61405f 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1689,6 +1689,10 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
+#ifdef QT_DEBUG
+        lastCalculationUsedSimplex[orientation] = true;
+#endif
+
         // Solve min and max size hints for trunk
         qreal min, max;
         feasible = solveMinMax(trunkConstraints, trunkPath, &min, &max);
@@ -1738,6 +1742,10 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
+#ifdef QT_DEBUG
+        lastCalculationUsedSimplex[orientation] = false;
+#endif
+
         // No Simplex is necessary because the path was simplified all the way to a single
         // anchor.
         Q_ASSERT(trunkPath.positives.count() == 1);
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 9b50661..b14bc62 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -513,6 +513,10 @@ public:
     bool graphHasConflicts[2];
     QSet<QGraphicsLayoutItem *> m_floatItems[2];
 
+#ifdef QT_DEBUG
+    bool lastCalculationUsedSimplex[2];
+#endif
+
     uint calculateGraphCacheDirty : 1;
 };
 
diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index cf4e9b8..cef56b9 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -153,6 +153,15 @@ static bool layoutHasConflict(QGraphicsAnchorLayout *l)
     return QGraphicsAnchorLayoutPrivate::get(l)->hasConflicts();
 }
 
+static bool usedSimplex(QGraphicsAnchorLayout *l, Qt::Orientation o)
+{
+    QGraphicsAnchorLayoutPrivate::Orientation oo = (o == Qt::Horizontal) ?
+        QGraphicsAnchorLayoutPrivate::Horizontal :
+        QGraphicsAnchorLayoutPrivate::Vertical;
+
+    return QGraphicsAnchorLayoutPrivate::get(l)->lastCalculationUsedSimplex[oo];
+}
+
 void tst_QGraphicsAnchorLayout::simple()
 {
     QGraphicsWidget *w1 = createItem();
@@ -170,10 +179,14 @@ void tst_QGraphicsAnchorLayout::simple()
     l->addAnchors(l, w1, Qt::Vertical);
     l->addAnchors(l, w2, Qt::Vertical);
 
+    QCOMPARE(l->count(), 2);
+
     QGraphicsWidget p;
     p.setLayout(l);
+    p.adjustSize();
 
-    QCOMPARE(l->count(), 2);
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::simple_center()
@@ -213,6 +226,9 @@ void tst_QGraphicsAnchorLayout::simple_center()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize, QSizeF(200, 20));
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
 }
 
@@ -310,6 +326,9 @@ void tst_QGraphicsAnchorLayout::layoutDirection()
 
     QCOMPARE(checkReverseDirection(p), true);
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
     delete view;
 }
@@ -398,6 +417,9 @@ void tst_QGraphicsAnchorLayout::diagonal()
     QCOMPARE(e->geometry(), QRectF(100.0, 200.0, 75.0, 100.0));
     QCOMPARE(p.size(), testA);
 
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     QCOMPARE(checkReverseDirection(&p), true);
 
     c->setMinimumWidth(300);
@@ -494,6 +516,9 @@ void tst_QGraphicsAnchorLayout::parallel()
     QCOMPARE(e->geometry(), QRectF(375, 400, 175, 100));
     QCOMPARE(f->geometry(), QRectF(550, 500, 200, 100));
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::parallel2()
@@ -539,6 +564,9 @@ void tst_QGraphicsAnchorLayout::parallel2()
 
     p.resize(layoutMaximumSize);
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::snake()
@@ -749,6 +777,9 @@ void tst_QGraphicsAnchorLayout::fairDistribution()
     QCOMPARE(c->geometry(), QRectF(200.0, 200.0, 100.0, 100.0));
     QCOMPARE(d->geometry(), QRectF(0.0, 300.0, 300.0, 100.0));
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
@@ -825,6 +856,9 @@ void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
     QCOMPARE(a->size(), d->size());
     QCOMPARE(e->size().width(), 4 * a->size().width());
     QCOMPARE(p.size(), layoutMaximumSize);
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::proportionalPreferred()
@@ -887,6 +921,9 @@ void tst_QGraphicsAnchorLayout::proportionalPreferred()
     QCOMPARE(a->size().width(), 10 * factor);
     QCOMPARE(c->size().width(), 14 * factor);
     QCOMPARE(p.size(), QSizeF(12, 400));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::example()
@@ -970,6 +1007,9 @@ void tst_QGraphicsAnchorLayout::example()
     QCOMPARE(a->size(), e->size());
     QCOMPARE(b->size(), d->size());
     QCOMPARE(f->size(), g->size());
+
+    QVERIFY(usedSimplex(l, Qt::Horizontal));
+    QVERIFY(usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::setSpacing()
@@ -1291,6 +1331,9 @@ void tst_QGraphicsAnchorLayout::sizePolicy()
     QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(100, 100));
     QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(100, 100));
 
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     delete p;
     delete view;
 }
@@ -1381,6 +1424,9 @@ void tst_QGraphicsAnchorLayout::expandingSequence()
 
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(200));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
@@ -1442,6 +1488,9 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(400));
 
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
+
     // Now we change D to have more "room for growth" from its preferred size
     // to its maximum size. We expect a proportional fair distribution. Note that
     // this seems to not conform with what QGraphicsLinearLayout does.
@@ -1464,6 +1513,9 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QCOMPARE(b->geometry().size(), pref + QSizeF(25, 0));
     QCOMPARE(c->geometry().size(), pref);
     QCOMPARE(d->geometry().size(), pref + QSizeF(50, 0));
+
+    QVERIFY(!usedSimplex(l, Qt::Horizontal));
+    QVERIFY(!usedSimplex(l, Qt::Vertical));
 }
 
 void tst_QGraphicsAnchorLayout::expandingParallel()
-- 
cgit v0.12


From eb2717ccbb20334b52aea269303258fe6236c117 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 15:52:11 -0300
Subject: QGAL: avoid having to re-calculate lists of variables

Change the functions solvePreferred() and solveExpanding() to take a
list of variables, so they don't need to calculate them based on the
list of constraints. That way, the trunk variables are calculated only
once.

This commit also reduce the scope of 'sizeHintConstraints' variable
instead of clearing and reusing it.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 50 +++++++++++-------------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |  8 ++--
 2 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index b61405f..485743e 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1671,9 +1671,7 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
     // of the "trunk" set of constraints and variables.
     // ### does trunk always exist? empty = trunk is the layout left->center->right
     QList<QSimplexConstraint *> trunkConstraints = parts[0];
-    QList<QSimplexConstraint *> sizeHintConstraints;
-    sizeHintConstraints = constraintsFromSizeHints(getVariables(trunkConstraints));
-    trunkConstraints += sizeHintConstraints;
+    QList<AnchorData *> trunkVariables = getVariables(trunkConstraints);
 
     // For minimum and maximum, use the path between the two layout sides as the
     // objective function.
@@ -1695,26 +1693,24 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
         // Solve min and max size hints for trunk
         qreal min, max;
-        feasible = solveMinMax(trunkConstraints, trunkPath, &min, &max);
+
+        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(trunkVariables);
+        QList<QSimplexConstraint *> allTrunkConstraints = trunkConstraints + sizeHintConstraints;
+
+        feasible = solveMinMax(allTrunkConstraints, trunkPath, &min, &max);
 
         if (feasible) {
             // Solve for preferred. The objective function is calculated from the constraints
             // and variables internally.
-            solvePreferred(trunkConstraints);
-
-            // remove sizeHintConstraints from trunkConstraints
-            trunkConstraints = parts[0];
+            solvePreferred(allTrunkConstraints, trunkVariables);
 
             // Solve for expanding. The objective function and the constraints from items
-            // are calculated internally.
-            solveExpanding(trunkConstraints);
+            // are calculated internally. Note that we don't include the sizeHintConstraints, since
+            // they have a different logic for solveExpanding().
+            solveExpanding(trunkConstraints, trunkVariables);
 
             // Propagate the new sizes down the simplified graph, ie. tell the
             // group anchors to set their children anchors sizes.
-
-            // ### we calculated variables already a few times, can't we reuse that?
-            QList<AnchorData *> trunkVariables = getVariables(trunkConstraints);
-
             for (int i = 0; i < trunkVariables.count(); ++i)
                 trunkVariables.at(i)->updateChildrenSizes();
 
@@ -1736,6 +1732,9 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             sizeHints[orientation][Qt::MaximumSize] = max;
             sizeAtExpanding[orientation] = expanding;
         }
+
+        qDeleteAll(sizeHintConstraints);
+
     } else {
 #if 0
         qDebug("Simplex NOT used for trunk of %s",
@@ -1766,10 +1765,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         sizeAtExpanding[orientation] = ad->sizeAtExpanding;
     }
 
-    // Delete the constraints, we won't use them anymore.
-    qDeleteAll(sizeHintConstraints);
-    sizeHintConstraints.clear();
-
     // For the other parts that not the trunk, solve only for the preferred size
     // that is the size they will remain at, since they are not stretched by the
     // layout.
@@ -1781,9 +1776,9 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             QList<AnchorData *> partVariables = getVariables(partConstraints);
             Q_ASSERT(!partVariables.isEmpty());
 
-            sizeHintConstraints = constraintsFromSizeHints(partVariables);
+            QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(partVariables);
             partConstraints += sizeHintConstraints;
-            feasible &= solvePreferred(partConstraints);
+            feasible &= solvePreferred(partConstraints, partVariables);
             if (!feasible)
                 break;
 
@@ -1800,7 +1795,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
             // Delete the constraints, we won't use them anymore.
             qDeleteAll(sizeHintConstraints);
-            sizeHintConstraints.clear();
         }
     }
     graphHasConflicts[orientation] = !feasible;
@@ -2318,7 +2312,7 @@ void QGraphicsAnchorLayoutPrivate::interpolateSequentialEdges(
         interpolateEdge(prev, data->m_edges.last(), orientation);
 }
 
-bool QGraphicsAnchorLayoutPrivate::solveMinMax(QList<QSimplexConstraint *> constraints,
+bool QGraphicsAnchorLayoutPrivate::solveMinMax(const QList<QSimplexConstraint *> &constraints,
                                                GraphPath path, qreal *min, qreal *max)
 {
     QSimplex simplex;
@@ -2359,9 +2353,9 @@ bool QGraphicsAnchorLayoutPrivate::solveMinMax(QList<QSimplexConstraint *> const
     return feasible;
 }
 
-bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> constraints)
+bool QGraphicsAnchorLayoutPrivate::solvePreferred(const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
 {
-    QList<AnchorData *> variables = getVariables(constraints);
     QList<QSimplexConstraint *> preferredConstraints;
     QList<QSimplexVariable *> preferredVariables;
     QSimplexConstraint objective;
@@ -2384,7 +2378,7 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
     //      A + A_shrinker - A_grower = A_pref
     //
     for (int i = 0; i < variables.size(); ++i) {
-        AnchorData *ad = static_cast<AnchorData *>(variables[i]);
+        AnchorData *ad = variables[i];
         if (ad->skipInPreferred)
             continue;
 
@@ -2415,7 +2409,7 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
 
         // Save sizeAtPreferred results
         for (int i = 0; i < variables.size(); ++i) {
-            AnchorData *ad = static_cast<AnchorData *>(variables[i]);
+            AnchorData *ad = variables[i];
             ad->sizeAtPreferred = ad->result;
         }
 
@@ -2476,9 +2470,9 @@ bool QGraphicsAnchorLayoutPrivate::solvePreferred(QList<QSimplexConstraint *> co
           expanding ones will shrink. Only after non-expanding anchors have
           shrinked all the way, the expanding anchors will start to shrink too.
 */
-void QGraphicsAnchorLayoutPrivate::solveExpanding(QList<QSimplexConstraint *> constraints)
+void QGraphicsAnchorLayoutPrivate::solveExpanding(const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
 {
-    QList<AnchorData *> variables = getVariables(constraints);
     QList<QSimplexConstraint *> itemConstraints;
     QSimplexConstraint *objective = new QSimplexConstraint;
     bool hasExpanding = false;
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index b14bc62..1d7b758 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -471,10 +471,12 @@ public:
                                   Orientation orientation);
 
     // Linear Programming solver methods
-    bool solveMinMax(QList<QSimplexConstraint *> constraints,
+    bool solveMinMax(const QList<QSimplexConstraint *> &constraints,
                      GraphPath path, qreal *min, qreal *max);
-    bool solvePreferred(QList<QSimplexConstraint *> constraints);
-    void solveExpanding(QList<QSimplexConstraint *> constraints);
+    bool solvePreferred(const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
+    void solveExpanding(const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
     bool hasConflicts() const;
 
 #ifdef QT_DEBUG
-- 
cgit v0.12


From e7e67b26fcd6c53dd822b1ae36074d418d432b4a Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 16:55:42 -0300
Subject: QGAL: update the sizes of all anchors instead of doing it separatedly

After calculations, update the size of all anchors in the simplified
graph. Those updates were happening locally after each calculation
(trunk and semifloats), however some anchors that were not involved in
simplex calculation were missing.

One concrete consequence of the previous behaviour is that semifloat
parts that were simplified into just one anchor, didn't have the chance
to set their sizeAt* values.  One consequence of the new behaviour is
one more test passing.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp   | 28 +++++++++++++++-------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h     |  1 +
 .../tst_qgraphicsanchorlayout1.cpp                 |  2 --
 3 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 485743e..260e8dc 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1709,11 +1709,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
             // they have a different logic for solveExpanding().
             solveExpanding(trunkConstraints, trunkVariables);
 
-            // Propagate the new sizes down the simplified graph, ie. tell the
-            // group anchors to set their children anchors sizes.
-            for (int i = 0; i < trunkVariables.count(); ++i)
-                trunkVariables.at(i)->updateChildrenSizes();
-
             // Calculate and set the preferred and expanding sizes for the layout,
             // from the edge sizes that were calculated above.
             qreal pref(0.0);
@@ -1756,9 +1751,6 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         ad->sizeAtExpanding = ad->expSize;
         ad->sizeAtMaximum = ad->maxSize;
 
-        // Propagate
-        ad->updateChildrenSizes();
-
         sizeHints[orientation][Qt::MinimumSize] = ad->sizeAtMinimum;
         sizeHints[orientation][Qt::PreferredSize] = ad->sizeAtPreferred;
         sizeHints[orientation][Qt::MaximumSize] = ad->sizeAtMaximum;
@@ -1790,13 +1782,17 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
                 ad->sizeAtMinimum = ad->sizeAtPreferred;
                 ad->sizeAtExpanding = ad->sizeAtPreferred;
                 ad->sizeAtMaximum = ad->sizeAtPreferred;
-                ad->updateChildrenSizes();
             }
 
             // Delete the constraints, we won't use them anymore.
             qDeleteAll(sizeHintConstraints);
         }
     }
+
+    // Propagate the new sizes down the simplified graph, ie. tell the
+    // group anchors to set their children anchors sizes.
+    updateAnchorSizes(orientation);
+
     graphHasConflicts[orientation] = !feasible;
 
     // Clean up our data structures. They are not needed anymore since
@@ -1907,6 +1903,20 @@ void QGraphicsAnchorLayoutPrivate::constraintsFromPaths(Orientation orientation)
 
 /*!
   \internal
+*/
+void QGraphicsAnchorLayoutPrivate::updateAnchorSizes(Orientation orientation)
+{
+    Graph<AnchorVertex, AnchorData> &g = graph[orientation];
+    const QList<QPair<AnchorVertex *, AnchorVertex *> > &vertices = g.connections();
+
+    for (int i = 0; i < vertices.count(); ++i) {
+        AnchorData *ad = g.edgeData(vertices.at(i).first, vertices.at(i).second);
+        ad->updateChildrenSizes();
+    }
+}
+
+/*!
+  \internal
 
   Create LP constraints for each anchor based on its minimum and maximum
   sizes, as specified in its size hints
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 1d7b758..e045fbd 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -441,6 +441,7 @@ public:
     void setAnchorSizeHintsFromItems(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
+    void updateAnchorSizes(Orientation orientation);
     QList<QSimplexConstraint *> constraintsFromSizeHints(const QList<AnchorData *> &anchors);
     QList<QList<QSimplexConstraint *> > getGraphParts(Orientation orientation);
     void identifyFloatItems(const QSet<AnchorData *> &visited, Orientation orientation);
diff --git a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
index 148b2c8..755d866 100644
--- a/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
+++ b/tests/auto/qgraphicsanchorlayout1/tst_qgraphicsanchorlayout1.cpp
@@ -1711,8 +1711,6 @@ void tst_QGraphicsAnchorLayout1::testBasicLayout()
 
     // Validate
     for (int i = 0; i < result.count(); ++i) {
-        if (i == 1)
-            QEXPECT_FAIL("Two, mixed", "Works with simplification disabled.", Continue);
         const BasicLayoutTestResult item = result[i];
         QCOMPARE(widgets[item.index]->geometry(), item.rect);
     }
-- 
cgit v0.12


From aff8e7a24e5e8cc1f330a1b3c2947ba4d07d51ed Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Thu, 8 Oct 2009 20:09:21 -0300
Subject: QGAL: refactor calculateGraphs() method

Create calculateTrunk() and calculateNonTrunk() methods, that
calculate sizes for anchors in different parts of the simplified graph
(using simplex when needed).

Also fixes a minor leak when the nontrunk part is non-feasible. The
old code left the loop leaving the contents of 'sizeHintConstraints'
not allocated.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 161 ++++++++++++-----------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   |   7 +
 2 files changed, 93 insertions(+), 75 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 260e8dc..c9821ae 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1600,7 +1600,8 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs()
     calculateGraphCacheDirty = 0;
 }
 
-// ### remove me:
+// ### Maybe getGraphParts could return the variables when traversing, at least
+// for trunk...
 QList<AnchorData *> getVariables(QList<QSimplexConstraint *> constraints)
 {
     QSet<AnchorData *> variableSet;
@@ -1664,8 +1665,7 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
     //  2) The floating or semi-floating anchors (items) that are those which
     //     are connected to only one (or none) of the layout sides, thus are not
     //     influenced by the layout size.
-    QList<QList<QSimplexConstraint *> > parts;
-    parts = getGraphParts(orientation);
+    QList<QList<QSimplexConstraint *> > parts = getGraphParts(orientation);
 
     // Now run the simplex solver to calculate Minimum, Preferred and Maximum sizes
     // of the "trunk" set of constraints and variables.
@@ -1675,49 +1675,82 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
     // For minimum and maximum, use the path between the two layout sides as the
     // objective function.
-
-    // Retrieve that path
     AnchorVertex *v = internalVertex(q, pickEdge(Qt::AnchorRight, orientation));
     GraphPath trunkPath = graphPaths[orientation].value(v);
 
+    bool feasible = calculateTrunk(orientation, trunkPath, trunkConstraints, trunkVariables);
+
+    // For the other parts that not the trunk, solve only for the preferred size
+    // that is the size they will remain at, since they are not stretched by the
+    // layout.
+
+    // Skipping the first (trunk)
+    for (int i = 1; i < parts.count(); ++i) {
+        if (!feasible)
+            break;
+
+        QList<QSimplexConstraint *> partConstraints = parts[i];
+        QList<AnchorData *> partVariables = getVariables(partConstraints);
+        Q_ASSERT(!partVariables.isEmpty());
+        feasible &= calculateNonTrunk(partConstraints, partVariables);
+    }
+
+    // Propagate the new sizes down the simplified graph, ie. tell the
+    // group anchors to set their children anchors sizes.
+    updateAnchorSizes(orientation);
+
+    graphHasConflicts[orientation] = !feasible;
+
+    // Clean up our data structures. They are not needed anymore since
+    // distribution uses just interpolation.
+    qDeleteAll(constraints[orientation]);
+    constraints[orientation].clear();
+    graphPaths[orientation].clear(); // ###
+}
+
+/*!
+    \internal
+
+    Calculate the sizes for all anchors which are part of the trunk. This works
+    on top of a (possibly) simplified graph.
+*/
+bool QGraphicsAnchorLayoutPrivate::calculateTrunk(Orientation orientation, const GraphPath &path,
+                                                  const QList<QSimplexConstraint *> &constraints,
+                                                  const QList<AnchorData *> &variables)
+{
     bool feasible = true;
-    if (!trunkConstraints.isEmpty()) {
-#if 0
-        qDebug("Simplex used for trunk of %s",
-               orientation == Horizontal ? "Horizontal" : "Vertical");
-#endif
+    bool needsSimplex = !constraints.isEmpty();
 
-#ifdef QT_DEBUG
-        lastCalculationUsedSimplex[orientation] = true;
+#if 0
+    qDebug("Simplex %s for trunk of %s", needsSimplex ? "used" : "NOT used",
+           orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
-        // Solve min and max size hints for trunk
-        qreal min, max;
+    if (needsSimplex) {
 
-        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(trunkVariables);
-        QList<QSimplexConstraint *> allTrunkConstraints = trunkConstraints + sizeHintConstraints;
+        QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(variables);
+        QList<QSimplexConstraint *> allConstraints = constraints + sizeHintConstraints;
 
-        feasible = solveMinMax(allTrunkConstraints, trunkPath, &min, &max);
+        // Solve min and max size hints
+        qreal min, max;
+        feasible = solveMinMax(allConstraints, path, &min, &max);
 
         if (feasible) {
-            // Solve for preferred. The objective function is calculated from the constraints
-            // and variables internally.
-            solvePreferred(allTrunkConstraints, trunkVariables);
+            solvePreferred(allConstraints, variables);
 
-            // Solve for expanding. The objective function and the constraints from items
-            // are calculated internally. Note that we don't include the sizeHintConstraints, since
-            // they have a different logic for solveExpanding().
-            solveExpanding(trunkConstraints, trunkVariables);
+            // Note that we don't include the sizeHintConstraints, since they
+            // have a different logic for solveExpanding().
+            solveExpanding(constraints, variables);
 
             // Calculate and set the preferred and expanding sizes for the layout,
             // from the edge sizes that were calculated above.
             qreal pref(0.0);
             qreal expanding(0.0);
-            foreach (const AnchorData *ad, trunkPath.positives) {
+            foreach (const AnchorData *ad, path.positives) {
                 pref += ad->sizeAtPreferred;
                 expanding += ad->sizeAtExpanding;
             }
-            foreach (const AnchorData *ad, trunkPath.negatives) {
+            foreach (const AnchorData *ad, path.negatives) {
                 pref -= ad->sizeAtPreferred;
                 expanding -= ad->sizeAtExpanding;
             }
@@ -1731,21 +1764,12 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         qDeleteAll(sizeHintConstraints);
 
     } else {
-#if 0
-        qDebug("Simplex NOT used for trunk of %s",
-               orientation == Horizontal ? "Horizontal" : "Vertical");
-#endif
-
-#ifdef QT_DEBUG
-        lastCalculationUsedSimplex[orientation] = false;
-#endif
-
         // No Simplex is necessary because the path was simplified all the way to a single
         // anchor.
-        Q_ASSERT(trunkPath.positives.count() == 1);
-        Q_ASSERT(trunkPath.negatives.count() == 0);
+        Q_ASSERT(path.positives.count() == 1);
+        Q_ASSERT(path.negatives.count() == 0);
 
-        AnchorData *ad = trunkPath.positives.toList()[0];
+        AnchorData *ad = path.positives.toList()[0];
         ad->sizeAtMinimum = ad->minSize;
         ad->sizeAtPreferred = ad->prefSize;
         ad->sizeAtExpanding = ad->expSize;
@@ -1757,49 +1781,36 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
         sizeAtExpanding[orientation] = ad->sizeAtExpanding;
     }
 
-    // For the other parts that not the trunk, solve only for the preferred size
-    // that is the size they will remain at, since they are not stretched by the
-    // layout.
+#ifdef QT_DEBUG
+    lastCalculationUsedSimplex[orientation] = needsSimplex;
+#endif
 
-    // Solve the other only for preferred, skip trunk
-    if (feasible) {
-        for (int i = 1; i < parts.count(); ++i) {
-            QList<QSimplexConstraint *> partConstraints = parts[i];
-            QList<AnchorData *> partVariables = getVariables(partConstraints);
-            Q_ASSERT(!partVariables.isEmpty());
-
-            QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(partVariables);
-            partConstraints += sizeHintConstraints;
-            feasible &= solvePreferred(partConstraints, partVariables);
-            if (!feasible)
-                break;
+    return feasible;
+}
 
-            // Propagate size at preferred to other sizes. Semi-floats
-            // always will be in their sizeAtPreferred.
-            for (int j = 0; j < partVariables.count(); ++j) {
-                AnchorData *ad = partVariables[j];
-                Q_ASSERT(ad);
-                ad->sizeAtMinimum = ad->sizeAtPreferred;
-                ad->sizeAtExpanding = ad->sizeAtPreferred;
-                ad->sizeAtMaximum = ad->sizeAtPreferred;
-            }
+/*!
+    \internal
+*/
+bool QGraphicsAnchorLayoutPrivate::calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,
+                                                     const QList<AnchorData *> &variables)
+{
+    QList<QSimplexConstraint *> sizeHintConstraints = constraintsFromSizeHints(variables);
+    bool feasible = solvePreferred(constraints + sizeHintConstraints, variables);
 
-            // Delete the constraints, we won't use them anymore.
-            qDeleteAll(sizeHintConstraints);
+    if (feasible) {
+        // Propagate size at preferred to other sizes. Semi-floats always will be
+        // in their sizeAtPreferred.
+        for (int j = 0; j < variables.count(); ++j) {
+            AnchorData *ad = variables[j];
+            Q_ASSERT(ad);
+            ad->sizeAtMinimum = ad->sizeAtPreferred;
+            ad->sizeAtExpanding = ad->sizeAtPreferred;
+            ad->sizeAtMaximum = ad->sizeAtPreferred;
         }
     }
 
-    // Propagate the new sizes down the simplified graph, ie. tell the
-    // group anchors to set their children anchors sizes.
-    updateAnchorSizes(orientation);
-
-    graphHasConflicts[orientation] = !feasible;
-
-    // Clean up our data structures. They are not needed anymore since
-    // distribution uses just interpolation.
-    qDeleteAll(constraints[orientation]);
-    constraints[orientation].clear();
-    graphPaths[orientation].clear(); // ###
+    qDeleteAll(sizeHintConstraints);
+    return feasible;
 }
 
 /*!
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index e045fbd..d96a035 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -438,6 +438,13 @@ public:
 
     void calculateGraphs();
     void calculateGraphs(Orientation orientation);
+
+    bool calculateTrunk(Orientation orientation, const GraphPath &trunkPath,
+                        const QList<QSimplexConstraint *> &constraints,
+                        const QList<AnchorData *> &variables);
+    bool calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,
+                           const QList<AnchorData *> &variables);
+
     void setAnchorSizeHintsFromItems(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
-- 
cgit v0.12


From 6a4d30b12baa85a223116d6629fa1e08e922d659 Mon Sep 17 00:00:00 2001
From: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Date: Tue, 13 Oct 2009 16:10:10 -0300
Subject: QGAL: refactor and document the simplification algorithm

Refactor the simplifyGraphIteration() function. The aim was to make it
more clear without changing too much the way it does stuff.

Before it collected a list of candidates and then filtered that into
sublists of same order, and after that removed the center edges from
the borders. It also reversed the list if the direction wasn't
forward, to pass it in forward order to simplifySequentialChunk()
helper function.

The refactored version

- take in account the order when building the candidates, this avoids
index manipulation;
- try to calculate 'beforeSequence' and 'afterSequence' as it builds the
candidates list;
- make simplifySequentialChunk() aware of directions, now it deals internally
with reversed direction sequences.

This commits also adds explanations to trickier parts of the code.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Artur Duque de Souza <artur.souza@openbossa.org>
Reviewed-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 324 ++++++++++++-----------
 1 file changed, 165 insertions(+), 159 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index c9821ae..937ccfa 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -506,36 +506,46 @@ static bool simplifySequentialChunk(Graph<AnchorVertex, AnchorData> *graph,
                                     const QVector<AnchorVertex*> &vertices,
                                     AnchorVertex *after)
 {
-    int i;
+    AnchorData *data = graph->edgeData(before, vertices.first());
+    Q_ASSERT(data);
+
+    const bool forward = (before == data->from);
+    QVector<AnchorVertex *> orderedVertices;
+
+    if (forward) {
+        orderedVertices = vertices;
+    } else {
+        qSwap(before, after);
+        for (int i = vertices.count() - 1; i >= 0; --i)
+            orderedVertices.append(vertices.at(i));
+    }
+
 #if defined(QT_DEBUG) && 0
     QString strVertices;
-    for (i = 0; i < vertices.count(); ++i)
-        strVertices += QString::fromAscii("%1 - ").arg(vertices.at(i)->toString());
+    for (int i = 0; i < orderedVertices.count(); ++i) {
+        strVertices += QString::fromAscii("%1 - ").arg(orderedVertices.at(i)->toString());
+    }
     QString strPath = QString::fromAscii("%1 - %2%3").arg(before->toString(), strVertices, after->toString());
     qDebug("simplifying [%s] to [%s - %s]", qPrintable(strPath), qPrintable(before->toString()), qPrintable(after->toString()));
 #endif
 
     SequentialAnchorData *sequence = new SequentialAnchorData;
     AnchorVertex *prev = before;
-    AnchorData *data;
-    for (i = 0; i <= vertices.count(); ++i) {
-        AnchorVertex *next = (i < vertices.count()) ? vertices.at(i) : after;
-        data = graph->takeEdge(prev, next);
-        sequence->m_edges.append(data);
+
+    for (int i = 0; i <= orderedVertices.count(); ++i) {
+        AnchorVertex *next = (i < orderedVertices.count()) ? orderedVertices.at(i) : after;
+        AnchorData *ad = graph->takeEdge(prev, next);
+        Q_ASSERT(ad);
+        sequence->m_edges.append(ad);
         prev = next;
     }
-    sequence->setVertices(vertices);
+
+    sequence->setVertices(orderedVertices);
     sequence->from = before;
     sequence->to = after;
 
     sequence->refreshSizeHints_helper(0, false);
 
-    // data here is the last edge in the sequence
-    // ### this seems to be here for supporting reverse order sequences,
-    // but doesnt seem to be used right now
-    if (data->from != vertices.last())
-        qSwap(sequence->from, sequence->to);
-
     // Note that since layout 'edges' can't be simplified away from
     // the graph, it's safe to assume that if there's a layout
     // 'edge', it'll be in the boundaries of the sequence.
@@ -590,15 +600,6 @@ static bool simplifySequentialChunk(Graph<AnchorVertex, AnchorData> *graph,
    2. Go to (1)
    3. Done
 
-
-   * Gathering sequential anchors *
-   The algorithm walks the graph in depth-first order, and only collects vertices that has two
-   edges connected to it. If the vertex does not have two edges or if it is a layout edge,
-   it will take all the previously collected vertices and try to create a simplified sequential
-   anchor representing all the previously collected vertices.
-   Once the simplified anchor is inserted, the collected list is cleared in order to find the next
-   sequence to simplify.
-   Note that there are some catches to this that are not covered by the above explanation.
 */
 void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
 {
@@ -615,9 +616,7 @@ void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
            orientation == Horizontal ? "Horizontal" : "Vertical");
 #endif
 
-    AnchorVertex *rootVertex = graph[orientation].rootVertex();
-
-    if (!rootVertex)
+    if (!graph[orientation].rootVertex())
         return;
 
     bool dirty;
@@ -626,164 +625,171 @@ void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
     } while (dirty);
 }
 
+/*!
+    \internal
+
+    One iteration of the simplification algorithm. Returns true if another iteration is needed.
+
+    The algorithm walks the graph in depth-first order, and only collects vertices that has two
+    edges connected to it.  If the vertex does not have two edges or if it is a layout edge, it
+    will take all the previously collected vertices and try to create a simplified sequential
+    anchor representing all the previously collected vertices.  Once the simplified anchor is
+    inserted, the collected list is cleared in order to find the next sequence to simplify.
+
+    Note that there are some catches to this that are not covered by the above explanation, see
+    the function comments for more details.
+*/
 bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutPrivate::Orientation orientation)
 {
     Q_Q(QGraphicsAnchorLayout);
     Graph<AnchorVertex, AnchorData> &g = graph[orientation];
-    AnchorVertex *v = g.rootVertex();
 
     QSet<AnchorVertex *> visited;
-    QStack<AnchorVertex *> stack;
-    stack.push(v);
+    QStack<QPair<AnchorVertex *, AnchorVertex *> > stack;
+    stack.push(qMakePair(static_cast<AnchorVertex *>(0), g.rootVertex()));
     QVector<AnchorVertex*> candidates;
+    bool candidatesForward;
 
     const Qt::AnchorPoint centerEdge = pickEdge(Qt::AnchorHorizontalCenter, orientation);
-    const Qt::AnchorPoint layoutEdge = oppositeEdge(v->m_edge);
 
-    bool dirty = false;
-
-    // walk depth-first.
+    // Walk depth-first, in the stack we store start of the candidate sequence (beforeSequence)
+    // and the vertex to be visited.
     while (!stack.isEmpty()) {
-        v = stack.pop();
-        QList<AnchorVertex *> vertices = g.adjacentVertices(v);
-        const int count = vertices.count();
-        bool endOfSequence = (v->m_item == q && v->m_edge == layoutEdge) || count != 2;
-        if (count == 2 && v->m_item != q) {
-            candidates.append(v);
-            if (visited.contains(vertices.first()) && visited.contains(vertices.last())) {
-                // in case of a cycle
-                endOfSequence = true;
+        QPair<AnchorVertex *, AnchorVertex *> pair = stack.pop();
+        AnchorVertex *beforeSequence = pair.first;
+        AnchorVertex *v = pair.second;
+
+        // The basic idea is to determine whether we found an end of sequence,
+        // if that's the case, we stop adding vertices to the candidate list
+        // and do a simplification step.
+        //
+        // A vertex can trigger an end of sequence if
+        // (a) it is a layout vertex, we don't simplify away the layout vertices;
+        // (b) it does not have exactly 2 adjacents;
+        // (c) it will change the direction of the sequence;
+        // (d) its next adjacent is already visited (a cycle in the graph).
+
+        const QList<AnchorVertex *> &adjacents = g.adjacentVertices(v);
+        const bool isLayoutVertex = v->m_item == q;
+        AnchorVertex *afterSequence = v;
+        bool endOfSequence = false;
+
+        //
+        // Identify the end cases.
+        //
+
+        // Identifies cases (a) and (b)
+        endOfSequence = isLayoutVertex || adjacents.count() != 2;
+
+        if (!endOfSequence) {
+            // If this is the first vertice, determine what is the direction to use for this
+            // sequence.
+            if (candidates.isEmpty()) {
+                const AnchorData *data = g.edgeData(beforeSequence, v);
+                Q_ASSERT(data);
+                candidatesForward = (beforeSequence == data->from);
             }
-        }
-        if (endOfSequence && candidates.count() >= 1) {
-            int i;
-            AnchorVertex *afterSequence= 0;
-            AnchorVertex *beforeSequence = 0;
-            // find the items before and after the valid sequence
-            if (candidates.count() == 1) {
-                QList<AnchorVertex *> beforeAndAfterVertices = g.adjacentVertices(candidates.at(0));
-                Q_ASSERT(beforeAndAfterVertices.count() == 2);
-                // Since we only have one vertex, we can pick
-                // any of the two vertices to become before/after.
-                afterSequence = beforeAndAfterVertices.last();
-                beforeSequence = beforeAndAfterVertices.first();
-            } else {
-                QList<AnchorVertex *> adjacentOfSecondLastVertex = g.adjacentVertices(candidates.last());
-                Q_ASSERT(adjacentOfSecondLastVertex.count() == 2);
-                if (adjacentOfSecondLastVertex.first() == candidates.at(candidates.count() - 2))
-                    afterSequence = adjacentOfSecondLastVertex.last();
-                else
-                    afterSequence = adjacentOfSecondLastVertex.first();
 
-                QList<AnchorVertex *> adjacentOfSecondVertex = g.adjacentVertices(candidates.first());
-                Q_ASSERT(adjacentOfSecondVertex.count() == 2);
-                if (adjacentOfSecondVertex.first() == candidates.at(1))
-                    beforeSequence = adjacentOfSecondVertex.last();
-                else
-                    beforeSequence = adjacentOfSecondVertex.first();
+            // This is a tricky part. We peek at the next vertex to find out
+            //
+            // - whether the edge from this vertex to the next vertex has the same direction;
+            // - whether we already visited the next vertex.
+            //
+            // Those are needed to identify (c) and (d). Note that unlike (a) and (b), we preempt
+            // the end of sequence by looking into the next vertex.
+
+            // Peek at the next vertex
+            AnchorVertex *after;
+            if (candidates.isEmpty())
+                after = (beforeSequence == adjacents.last() ? adjacents.first() : adjacents.last());
+            else
+                after = (candidates.last() == adjacents.last() ? adjacents.first() : adjacents.last());
+
+            // ### At this point we assumed that candidates will not contain 'after', this may not hold
+            // when simplifying FLOATing anchors.
+            Q_ASSERT(!candidates.contains(after));
+
+            const AnchorData *data = g.edgeData(v, after);
+            Q_ASSERT(data);
+            const bool willChangeDirection = (candidatesForward != (v == data->from));
+            const bool cycleFound = visited.contains(after);
+
+            // Now cases (c) and (d)...
+            endOfSequence = willChangeDirection || cycleFound;
+
+            if (endOfSequence) {
+                if (!willChangeDirection) {
+                    // If the direction will not change, we can add the current vertex to the
+                    // candidates list and we know that 'after' can be used as afterSequence.
+                    candidates.append(v);
+                    afterSequence = after;
+                }
+            } else {
+                // If it's not an end of sequence, then the vertex didn't trigger neither of the
+                // previously four cases, so it can be added to the candidates list.
+                candidates.append(v);
             }
-            // The complete path of the sequence to simplify is: beforeSequence, <candidates>, afterSequence
-            // where beforeSequence and afterSequence are the endpoints where the anchor is inserted
-            // between.
-#if defined(QT_DEBUG) && 0
-            // ### DEBUG
-            QString strCandidates;
-            for (i = 0; i < candidates.count(); ++i)
-                strCandidates += QString::fromAscii("%1 - ").arg(candidates.at(i)->toString());
-            QString strPath = QString::fromAscii("%1 - %2%3").arg(beforeSequence->toString(), strCandidates, afterSequence->toString());
-            qDebug("candidate list for sequential simplification:\n[%s]", qPrintable(strPath));
-#endif
+        }
 
-            bool forward = true;
-            AnchorVertex *prev = beforeSequence;
-            int intervalFrom = 0;
+        //
+        // Add next non-visited vertices to the stack.
+        //
+        for (int i = 0; i < adjacents.count(); ++i) {
+            AnchorVertex *next = adjacents.at(i);
+            if (visited.contains(next))
+                continue;
 
-            // Check for directionality (from). We don't want to destroy that information,
-            // thus we only combine anchors with the same direction.
+            // If current vertex is an end of sequence, and it'll reset the candidates list. So
+            // the next vertices will build candidates lists with the current vertex as 'before'
+            // vertex. If it's not an end of sequence, we keep the original 'before' vertex,
+            // since we are keeping the candidates list.
+            if (endOfSequence)
+                stack.push(qMakePair(v, next));
+            else
+                stack.push(qMakePair(beforeSequence, next));
+        }
 
-            // "i" is the index *including* the beforeSequence and afterSequence vertices.
-            for (i = 1; i <= candidates.count() + 1; ++i) {
-                bool atVertexAfter = i > candidates.count();
-                AnchorVertex *v1 = atVertexAfter ? afterSequence : candidates.at(i - 1);
-                AnchorData *data = g.edgeData(prev, v1);
-                Q_ASSERT(data);
-                if (i == 1) {
-                    forward = (prev == data->from ? true : false);
-                } else if (forward != (prev == data->from) || atVertexAfter) {
-                    int intervalTo = i;
-                    if (forward != (prev == data->from))
-                        --intervalTo;
-
-                    // intervalFrom and intervalTo should now be indices to the vertex before and
-                    // after the sequential anchor.
-                    if (intervalTo - intervalFrom >= 2) {
-                        // simplify in the range [intervalFrom, intervalTo]
-
-                        // Trim off internal center anchors (Left-Center/Center-Right) from the
-                        // start and the end of the sequence. We never want to simplify internal
-                        // center anchors where there is an external anchor connected to the center.
-                        AnchorVertex *intervalVertexFrom = intervalFrom == 0 ? beforeSequence : candidates.at(intervalFrom - 1);
-                        int effectiveIntervalFrom = intervalFrom;
-                        if (intervalVertexFrom->m_edge == centerEdge
-                            && intervalVertexFrom->m_item == candidates.at(effectiveIntervalFrom)->m_item) {
-                            ++effectiveIntervalFrom;
-                            intervalVertexFrom = candidates.at(effectiveIntervalFrom - 1);
-                        }
-                        AnchorVertex *intervalVertexTo = intervalTo <= candidates.count() ? candidates.at(intervalTo - 1) : afterSequence;
-                        int effectiveIntervalTo = intervalTo;
-                        if (intervalVertexTo->m_edge == centerEdge
-                            && intervalVertexTo->m_item == candidates.at(effectiveIntervalTo - 2)->m_item) {
-                            --effectiveIntervalTo;
-                            intervalVertexTo = candidates.at(effectiveIntervalTo - 1);
-                        }
-                        if (effectiveIntervalTo - effectiveIntervalFrom >= 2) {
-                            QVector<AnchorVertex*> subCandidates;
-                            if (forward) {
-                               subCandidates = candidates.mid(effectiveIntervalFrom, effectiveIntervalTo - effectiveIntervalFrom - 1);
-                            } else {
-                                // reverse the order of the candidates.
-                                qSwap(intervalVertexFrom, intervalVertexTo);
-                                do {
-                                    ++effectiveIntervalFrom;
-                                    subCandidates.prepend(candidates.at(effectiveIntervalFrom - 1));
-                                } while (effectiveIntervalFrom < effectiveIntervalTo - 1);
-                            }
-                            if (simplifySequentialChunk(&g, intervalVertexFrom, subCandidates, intervalVertexTo)) {
-                                dirty = true;
-                                break;
-                            }
-                            // finished simplification of chunk with same direction
-                        }
-                    }
-                    if (forward == (prev == data->from))
-                        --intervalTo;
-                    intervalFrom = intervalTo;
-
-                    forward = !forward;
-                }
-                prev = v1;
-            }
+        visited.insert(v);
 
-            if (dirty)
-                break;
-        }
+        if (!endOfSequence || candidates.isEmpty())
+            continue;
+
+        //
+        // Create a sequence for (beforeSequence, candidates, afterSequence).
+        //
 
-        if (endOfSequence)
-            candidates.clear();
+        // One restriction we have is to not simplify half of an anchor and let the other half
+        // unsimplified. So we remove center edges before and after the sequence.
+        if (beforeSequence->m_edge == centerEdge && beforeSequence->m_item == candidates.first()->m_item) {
+            beforeSequence = candidates.first();
+            candidates.remove(0);
 
-        for (int i = 0; i < count; ++i) {
-            AnchorVertex *next = vertices.at(i);
-            if (next->m_item == q && next->m_edge == centerEdge)
+            // If there's not candidates to be simplified, leave.
+            if (candidates.isEmpty())
                 continue;
-            if (visited.contains(next))
+        }
+
+        if (afterSequence->m_edge == centerEdge && afterSequence->m_item == candidates.last()->m_item) {
+            afterSequence = candidates.last();
+            candidates.remove(candidates.count() - 1);
+
+            if (candidates.isEmpty())
                 continue;
-            stack.push(next);
         }
 
-        visited.insert(v);
+        // This function will remove the candidates from the graph and create one edge between
+        // beforeSequence and afterSequence. This function returns true if the sequential
+        // simplification also caused a parallel simplification to be created. In this case we end
+        // the iteration and start again (since all the visited state we have may be outdated).
+        if (simplifySequentialChunk(&g, beforeSequence, candidates, afterSequence))
+            return true;
+
+        // If there was no parallel simplification, we'll keep walking the graph. So we clear the
+        // candidates list to start again.
+        candidates.clear();
     }
 
-    return dirty;
+    return false;
 }
 
 static void restoreSimplifiedAnchor(Graph<AnchorVertex, AnchorData> &g,
-- 
cgit v0.12


From 8ef83e60df0291ba2a36cc744e1f0c11f465f1e2 Mon Sep 17 00:00:00 2001
From: Gabriel de Dietrich <gabriel.dietrich-de@nokia.com>
Date: Thu, 15 Oct 2009 18:45:13 +0200
Subject: Fixed a rare crash in qt_x11_enforce_cursor

A QPointer was set to point to a QWidget by one of its children, during its
deletion. This happens during the child deletion, and after the call to
QObject::clearGuards(), which means that the QPointer becomes a dangling one.

The fix ensures that qt_x11_enforce_cursor will not be called with a
being-deleted QWidget. The included auto-test doesn't test anything, except
that it doesn't crash.

Reviewed-by: Olivier
---
 src/gui/kernel/qapplication.cpp    |  5 ++++-
 tests/auto/qwidget/tst_qwidget.cpp | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/src/gui/kernel/qapplication.cpp b/src/gui/kernel/qapplication.cpp
index b990fe2..5476e36 100644
--- a/src/gui/kernel/qapplication.cpp
+++ b/src/gui/kernel/qapplication.cpp
@@ -2662,7 +2662,10 @@ void QApplicationPrivate::dispatchEnterLeave(QWidget* enter, QWidget* leave) {
         if (!isAlien(w))
             break;
         if (w->testAttribute(Qt::WA_SetCursor)) {
-            parentOfLeavingCursor = w->parentWidget();
+            QWidget *parent = w->parentWidget();
+            while (parent && parent->d_func()->data.in_destructor)
+                parent = parent->parentWidget();
+            parentOfLeavingCursor = parent;
             //continue looping, we need to find the downest alien widget with a cursor.
             // (downest on the screen)
         }
diff --git a/tests/auto/qwidget/tst_qwidget.cpp b/tests/auto/qwidget/tst_qwidget.cpp
index daeee3d..4cb9f72 100644
--- a/tests/auto/qwidget/tst_qwidget.cpp
+++ b/tests/auto/qwidget/tst_qwidget.cpp
@@ -69,6 +69,9 @@
 #include <QtGui/qpaintengine.h>
 #include <private/qbackingstore_p.h>
 
+#include <QtGui/QGraphicsView>
+#include <QtGui/QGraphicsProxyWidget>
+
 #include "../../shared/util.h"
 
 
@@ -285,6 +288,7 @@ private slots:
 #ifdef Q_WS_X11
     void minAndMaxSizeWithX11BypassWindowManagerHint();
     void showHideShow();
+    void clean_qt_x11_enforce_cursor();
 #endif
 
     void compatibilityChildInsertedEvents();
@@ -6048,6 +6052,35 @@ void tst_QWidget::showHideShow()
 
     QVERIFY(w.gotExpectedMapNotify);
 }
+
+void tst_QWidget::clean_qt_x11_enforce_cursor()
+{
+    {
+        QWidget window;
+        QWidget *w = new QWidget(&window);
+        QWidget *child = new QWidget(w);
+        child->setAttribute(Qt::WA_SetCursor, true);
+
+        window.show();
+        QApplication::setActiveWindow(&window);
+        QTest::qWaitForWindowShown(&window);
+        QTest::qWait(100);
+        QCursor::setPos(window.geometry().center());
+        QTest::qWait(100);
+
+        child->setFocus();
+        QApplication::processEvents();
+        QTest::qWait(100);
+
+        delete w;
+    }
+
+    QGraphicsScene scene;
+    QLineEdit *edit = new QLineEdit;
+    scene.addWidget(edit);
+
+    // If the test didn't crash, then it passed.
+}
 #endif
 
 class EventRecorder : public QObject
-- 
cgit v0.12


From db795de8e92da117070c45fb963273a6fa61c688 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 15 Oct 2009 11:16:32 -0300
Subject: QGraphicsAnchorLayout: Mark expected failures in tests w/o
 simplification

Some tests are expected to fail when run without simplification, ie. by
setting the environment var QT_ANCHORLAYOUT_NO_SIMPLIFICATION.

This commit adds QEXPECT_FAIL before those tests. In some cases
the failures are random therefore we must disable the test instead.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 .../tst_qgraphicsanchorlayout.cpp                  | 91 ++++++++++++++++------
 1 file changed, 67 insertions(+), 24 deletions(-)

diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index cef56b9..a51d2ab 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -49,6 +49,14 @@
 class tst_QGraphicsAnchorLayout : public QObject {
     Q_OBJECT;
 
+public:
+    tst_QGraphicsAnchorLayout() : QObject() {
+        hasSimplification = qgetenv("QT_ANCHORLAYOUT_NO_SIMPLIFICATION").isEmpty();
+    }
+
+private:
+    bool hasSimplification;
+
 private slots:
     void simple();
     void simple_center();
@@ -185,8 +193,10 @@ void tst_QGraphicsAnchorLayout::simple()
     p.setLayout(l);
     p.adjustSize();
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::simple_center()
@@ -226,8 +236,10 @@ void tst_QGraphicsAnchorLayout::simple_center()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize, QSizeF(200, 20));
 
-    QVERIFY(usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 
     delete p;
 }
@@ -326,8 +338,10 @@ void tst_QGraphicsAnchorLayout::layoutDirection()
 
     QCOMPARE(checkReverseDirection(p), true);
 
-    QVERIFY(usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 
     delete p;
     delete view;
@@ -417,8 +431,10 @@ void tst_QGraphicsAnchorLayout::diagonal()
     QCOMPARE(e->geometry(), QRectF(100.0, 200.0, 75.0, 100.0));
     QCOMPARE(p.size(), testA);
 
-    QVERIFY(usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 
     QCOMPARE(checkReverseDirection(&p), true);
 
@@ -496,6 +512,9 @@ void tst_QGraphicsAnchorLayout::parallel()
     QCOMPARE(f->geometry(), QRectF(350, 500, 100, 100));
     QCOMPARE(p.size(), layoutMinimumSize);
 
+    if (!hasSimplification)
+        return;
+
     p.resize(layoutPreferredSize);
     QCOMPARE(a->geometry(), QRectF(0, 0, 150, 100));
     QCOMPARE(b->geometry(), QRectF(150, 100, 150, 100));
@@ -565,8 +584,10 @@ void tst_QGraphicsAnchorLayout::parallel2()
     p.resize(layoutMaximumSize);
     QCOMPARE(p.size(), layoutMaximumSize);
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::snake()
@@ -758,6 +779,8 @@ void tst_QGraphicsAnchorLayout::fairDistribution()
     QCOMPARE(layoutMaximumSize, QSizeF(300.0, 400.0));
 
     p.resize(layoutMinimumSize);
+    if (!hasSimplification)
+        QEXPECT_FAIL("", "Without simplification there is no fair distribution.", Abort);
     QCOMPARE(a->geometry(), QRectF(0.0, 0.0, 20.0, 100.0));
     QCOMPARE(b->geometry(), QRectF(20.0, 100.0, 20.0, 100.0));
     QCOMPARE(c->geometry(), QRectF(40.0, 200.0, 20.0, 100.0));
@@ -778,8 +801,10 @@ void tst_QGraphicsAnchorLayout::fairDistribution()
     QCOMPARE(d->geometry(), QRectF(0.0, 300.0, 300.0, 100.0));
     QCOMPARE(p.size(), layoutMaximumSize);
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
@@ -836,6 +861,9 @@ void tst_QGraphicsAnchorLayout::fairDistributionOppositeDirections()
     QCOMPARE(layoutPreferredSize, QSizeF(220.0, 500.0));
     QCOMPARE(layoutMaximumSize, QSizeF(400.0, 500.0));
 
+    if (!hasSimplification)
+        return;
+
     p.resize(layoutMinimumSize);
     QCOMPARE(a->size(), b->size());
     QCOMPARE(a->size(), c->size());
@@ -922,8 +950,10 @@ void tst_QGraphicsAnchorLayout::proportionalPreferred()
     QCOMPARE(c->size().width(), 14 * factor);
     QCOMPARE(p.size(), QSizeF(12, 400));
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::example()
@@ -1008,8 +1038,10 @@ void tst_QGraphicsAnchorLayout::example()
     QCOMPARE(b->size(), d->size());
     QCOMPARE(f->size(), g->size());
 
-    QVERIFY(usedSimplex(l, Qt::Horizontal));
-    QVERIFY(usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(usedSimplex(l, Qt::Horizontal));
+        QVERIFY(usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::setSpacing()
@@ -1331,8 +1363,10 @@ void tst_QGraphicsAnchorLayout::sizePolicy()
     QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(100, 100));
     QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(100, 100));
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 
     delete p;
     delete view;
@@ -1425,8 +1459,10 @@ void tst_QGraphicsAnchorLayout::expandingSequence()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(200));
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
@@ -1488,8 +1524,10 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QSizeF layoutMaximumSize = l->effectiveSizeHint(Qt::MaximumSize);
     QCOMPARE(layoutMaximumSize.width(), qreal(400));
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 
     // Now we change D to have more "room for growth" from its preferred size
     // to its maximum size. We expect a proportional fair distribution. Note that
@@ -1514,8 +1552,10 @@ void tst_QGraphicsAnchorLayout::expandingSequenceFairDistribution()
     QCOMPARE(c->geometry().size(), pref);
     QCOMPARE(d->geometry().size(), pref + QSizeF(50, 0));
 
-    QVERIFY(!usedSimplex(l, Qt::Horizontal));
-    QVERIFY(!usedSimplex(l, Qt::Vertical));
+    if (hasSimplification) {
+        QVERIFY(!usedSimplex(l, Qt::Horizontal));
+        QVERIFY(!usedSimplex(l, Qt::Vertical));
+    }
 }
 
 void tst_QGraphicsAnchorLayout::expandingParallel()
@@ -1672,6 +1712,9 @@ void tst_QGraphicsAnchorLayout::infiniteMaxSizes()
     QCOMPARE(c->geometry(), QRectF(100, 0, 50, 10));
     QCOMPARE(d->geometry(), QRectF(150, 0, 50, 10));
 
+    if (!hasSimplification)
+        QEXPECT_FAIL("", "Without simplification there is no fair distribution.", Abort);
+
     p.resize(1000, 10);
     QCOMPARE(a->geometry(), QRectF(0, 0, 450, 10));
     QCOMPARE(b->geometry(), QRectF(450, 0, 50, 10));
-- 
cgit v0.12


From c5609a9247b965ea57db98607ad498a216e179d6 Mon Sep 17 00:00:00 2001
From: "Eduardo M. Fleury" <eduardo.fleury@openbossa.org>
Date: Thu, 15 Oct 2009 15:25:03 -0300
Subject: QGAL: Add anchor layout vs nested linear layouts benchmark

Adding a benchmark to compare the use of three nested linear layouts
versus the use of a single anchor layout.

We also test two different anchor layout setups to achieve the
same visual result. In the first one we use the addCornerAnchors API
that, in the way it was used, adds reduntant anchors. The second uses
the basic addAnchor API to create only the essential anchors.

Currently the first setup is way slower than the second. That happens
because the redundant anchors create "zero-sized knots" in the graph,
that are not eaten by the simplification algorithm, thus requiring
the usage of the simplex solver.

Zero-sized knots are groups of three or more vertices that are linked
together by zero-sized anchors. In pratice, these vertices represent
the same place in the graph (remember, the distance between them is
zero), but to the simplification mechanism, they look like three
distinct ones.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
---
 .../tst_qgraphicsanchorlayout.cpp                  | 111 +++++++++++++++++++++
 1 file changed, 111 insertions(+)

diff --git a/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index 000ab6e..43dff93 100644
--- a/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -41,6 +41,7 @@
 
 #include <QtTest/QtTest>
 #include <QtGui/qgraphicsanchorlayout.h>
+#include <QtGui/qgraphicslinearlayout.h>
 #include <QtGui/qgraphicswidget.h>
 #include <QtGui/qgraphicsview.h>
 
@@ -54,6 +55,9 @@ public:
 private slots:
     void s60_hard_complex_data();
     void s60_hard_complex();
+    void linearVsAnchorNested_data();
+    void linearVsAnchorNested();
+
 };
 
 
@@ -192,6 +196,113 @@ void tst_QGraphicsAnchorLayout::s60_hard_complex()
     }
 }
 
+void tst_QGraphicsAnchorLayout::linearVsAnchorNested_data()
+{
+    QTest::addColumn<int>("whichLayout");
+    QTest::newRow("LinearLayout")
+        << 0;
+    QTest::newRow("AnchorLayout setup with null-anchors knot")
+        << 1;
+    QTest::newRow("AnchorLayout setup easy to simplificate")
+        << 2;
+}
+
+void tst_QGraphicsAnchorLayout::linearVsAnchorNested()
+{
+    QFETCH(int, whichLayout);
+
+    QSizeF min(10, 10);
+    QSizeF pref(80, 80);
+    QSizeF max(150, 150);
+
+    QGraphicsWidget *a = createItem(min, pref, max, "a");
+    QGraphicsWidget *b = createItem(min, pref, max, "b");
+    QGraphicsWidget *c = createItem(min, pref, max, "c");
+    QGraphicsWidget *d = createItem(min, pref, max, "d");
+
+    QGraphicsLayout *layout;
+
+    if (whichLayout == 0) {
+        QGraphicsLinearLayout *linear1 = new QGraphicsLinearLayout;
+        QGraphicsLinearLayout *linear2 = new QGraphicsLinearLayout(Qt::Vertical);
+        QGraphicsLinearLayout *linear3 = new QGraphicsLinearLayout;
+
+        linear1->addItem(a);
+        linear1->addItem(linear2);
+        linear2->addItem(b);
+        linear2->addItem(linear3);
+        linear3->addItem(c);
+        linear3->addItem(d);
+
+        layout = linear1;
+    } else if (whichLayout == 1) {
+        QGraphicsAnchorLayout *anchor = new QGraphicsAnchorLayout;
+
+        // A
+        anchor->addCornerAnchors(a, Qt::TopLeftCorner, anchor, Qt::TopLeftCorner);
+        anchor->addCornerAnchors(a, Qt::TopRightCorner, b, Qt::TopLeftCorner);
+        anchor->addCornerAnchors(a, Qt::BottomLeftCorner, anchor, Qt::BottomLeftCorner);
+        anchor->addCornerAnchors(a, Qt::BottomRightCorner, c, Qt::BottomLeftCorner);
+
+        // B
+        anchor->addCornerAnchors(b, Qt::TopRightCorner, anchor, Qt::TopRightCorner);
+        anchor->addCornerAnchors(b, Qt::BottomLeftCorner, c, Qt::TopLeftCorner);
+        anchor->addCornerAnchors(b, Qt::BottomRightCorner, d, Qt::TopRightCorner);
+
+        // C
+        anchor->addCornerAnchors(c, Qt::TopRightCorner, d, Qt::TopLeftCorner);
+        anchor->addCornerAnchors(c, Qt::BottomRightCorner, d, Qt::BottomLeftCorner);
+
+        // D
+        anchor->addCornerAnchors(d, Qt::BottomRightCorner, anchor, Qt::BottomRightCorner);
+
+        layout = anchor;
+    } else {
+        QGraphicsAnchorLayout *anchor = new QGraphicsAnchorLayout;
+
+        // A
+        anchor->addAnchor(a, Qt::AnchorLeft, anchor, Qt::AnchorLeft);
+        anchor->addAnchors(a, anchor, Qt::Vertical);
+        anchor->addAnchor(a, Qt::AnchorRight, b, Qt::AnchorLeft);
+        anchor->addAnchor(a, Qt::AnchorRight, c, Qt::AnchorLeft);
+
+        // B
+        anchor->addAnchor(b, Qt::AnchorTop, anchor, Qt::AnchorTop);
+        anchor->addAnchor(b, Qt::AnchorRight, anchor, Qt::AnchorRight);
+        anchor->addAnchor(b, Qt::AnchorBottom, c, Qt::AnchorTop);
+        anchor->addAnchor(b, Qt::AnchorBottom, d, Qt::AnchorTop);
+
+        // C
+        anchor->addAnchor(c, Qt::AnchorRight, d, Qt::AnchorLeft);
+        anchor->addAnchor(c, Qt::AnchorBottom, anchor, Qt::AnchorBottom);
+
+        // D
+        anchor->addAnchor(d, Qt::AnchorRight, anchor, Qt::AnchorRight);
+        anchor->addAnchor(d, Qt::AnchorBottom, anchor, Qt::AnchorBottom);
+
+        layout = anchor;
+    }
+
+    QSizeF sizeHint;
+    // warm up instruction cache
+    layout->invalidate();
+    sizeHint = layout->effectiveSizeHint(Qt::PreferredSize);
+
+    // ...then measure...
+    QBENCHMARK {
+        // To ensure that all sizeHints caches are invalidated in
+        // the LinearLayout setup, we must call updateGeometry on the
+        // children. If we didn't, only the top level layout would be
+        // re-calculated.
+        static_cast<QGraphicsLayoutItem *>(a)->updateGeometry();
+        static_cast<QGraphicsLayoutItem *>(b)->updateGeometry();
+        static_cast<QGraphicsLayoutItem *>(c)->updateGeometry();
+        static_cast<QGraphicsLayoutItem *>(d)->updateGeometry();
+        layout->invalidate();
+        sizeHint = layout->effectiveSizeHint(Qt::PreferredSize);
+    }
+}
+
 QTEST_MAIN(tst_QGraphicsAnchorLayout)
 
 #include "tst_qgraphicsanchorlayout.moc"
-- 
cgit v0.12


From ea52aef43acf862a51ea5b2eb65fa2ad60e5590f Mon Sep 17 00:00:00 2001
From: Jesus Sanchez-Palencia <jesus.palencia@openbossa.org>
Date: Wed, 14 Oct 2009 16:56:54 -0300
Subject: QGraphicsAnchorLayout: Adding two benchmarks on LinearLayout vs
 AnchorLayout cases

Signed-off-by: Jesus Sanchez-Palencia <jesus.palencia@openbossa.org>
Reviewed-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
---
 .../tst_qgraphicsanchorlayout.cpp                  | 127 ++++++++++++++++++++-
 1 file changed, 126 insertions(+), 1 deletion(-)

diff --git a/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index 43dff93..81064d7 100644
--- a/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/benchmarks/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -55,9 +55,12 @@ public:
 private slots:
     void s60_hard_complex_data();
     void s60_hard_complex();
+    void linearVsAnchorSizeHints_data();
+    void linearVsAnchorSizeHints();
+    void linearVsAnchorSetGeometry_data();
+    void linearVsAnchorSetGeometry();
     void linearVsAnchorNested_data();
     void linearVsAnchorNested();
-
 };
 
 
@@ -196,6 +199,128 @@ void tst_QGraphicsAnchorLayout::s60_hard_complex()
     }
 }
 
+static QGraphicsLayout* createLayouts(int whichLayout)
+{
+    QSizeF min(0, 10);
+    QSizeF pref(50, 10);
+    QSizeF max(100, 10);
+
+    QGraphicsWidget *a = createItem(min, pref, max, "a");
+    QGraphicsWidget *b = createItem(min, pref, max, "b");
+    QGraphicsWidget *c = createItem(min, pref, max, "c");
+    QGraphicsWidget *d = createItem(min, pref, max, "d");
+
+    QGraphicsLayout *l;
+    if (whichLayout == 0) {
+        l = new QGraphicsLinearLayout;
+        QGraphicsLinearLayout *linear = static_cast<QGraphicsLinearLayout *>(l);
+        linear->setContentsMargins(0, 0, 0, 0);
+
+        linear->addItem(a);
+        linear->addItem(b);
+        linear->addItem(c);
+        linear->addItem(d);
+    } else {
+        l = new QGraphicsAnchorLayout;
+        QGraphicsAnchorLayout *anchor = static_cast<QGraphicsAnchorLayout *>(l);
+        anchor->setContentsMargins(0, 0, 0, 0);
+
+        // Horizontal
+        setAnchor(anchor, anchor, Qt::AnchorLeft, a, Qt::AnchorLeft, 0);
+        setAnchor(anchor, a, Qt::AnchorRight, b, Qt::AnchorLeft, 0);
+        setAnchor(anchor, b, Qt::AnchorRight, c, Qt::AnchorLeft, 0);
+        setAnchor(anchor, c, Qt::AnchorRight, d, Qt::AnchorLeft, 0);
+        setAnchor(anchor, d, Qt::AnchorRight, anchor, Qt::AnchorRight, 0);
+
+        // Vertical
+        anchor->addAnchors(anchor, a, Qt::Vertical);
+        anchor->addAnchors(anchor, b, Qt::Vertical);
+        anchor->addAnchors(anchor, c, Qt::Vertical);
+        anchor->addAnchors(anchor, d, Qt::Vertical);
+    }
+
+    return l;
+}
+
+void tst_QGraphicsAnchorLayout::linearVsAnchorSizeHints_data()
+{
+    QTest::addColumn<int>("whichLayout");
+    QTest::addColumn<int>("whichSizeHint");
+
+    QTest::newRow("QGraphicsLinearLayout::minimum")
+        << 0 << int(Qt::MinimumSize);
+    QTest::newRow("QGraphicsLinearLayout::preferred")
+        << 0 << int(Qt::PreferredSize);
+    QTest::newRow("QGraphicsLinearLayout::maximum")
+        << 0 << int(Qt::MaximumSize);
+    QTest::newRow("QGraphicsLinearLayout::noSizeHint")
+        << 0 << -1;
+
+    QTest::newRow("QGraphicsAnchorLayout::minimum")
+        << 1 << int(Qt::MinimumSize);
+    QTest::newRow("QGraphicsAnchorLayout::preferred")
+        << 1 << int(Qt::PreferredSize);
+    QTest::newRow("QGraphicsAnchorLayout::maximum")
+        << 1 << int(Qt::MaximumSize);
+    QTest::newRow("QGraphicsAnchorLayout::noSizeHint")
+        << 1 << -1;
+}
+
+void tst_QGraphicsAnchorLayout::linearVsAnchorSizeHints()
+{
+    QFETCH(int, whichSizeHint);
+    QFETCH(int, whichLayout);
+
+    QGraphicsLayout *l = createLayouts(whichLayout);
+
+    QSizeF sizeHint;
+    // warm up instruction cache
+    l->invalidate();
+    sizeHint = l->effectiveSizeHint((Qt::SizeHint)whichSizeHint);
+    // ...then measure...
+
+    QBENCHMARK {
+        l->invalidate();
+        sizeHint = l->effectiveSizeHint((Qt::SizeHint)whichSizeHint);
+    }
+}
+
+void tst_QGraphicsAnchorLayout::linearVsAnchorSetGeometry_data()
+{
+    QTest::addColumn<int>("whichLayout");
+
+    QTest::newRow("QGraphicsLinearLayout")
+        << 0;
+    QTest::newRow("QGraphicsAnchorLayout")
+        << 1;
+}
+
+void tst_QGraphicsAnchorLayout::linearVsAnchorSetGeometry()
+{
+    QFETCH(int, whichLayout);
+
+    QGraphicsLayout *l = createLayouts(whichLayout);
+
+    QRectF sizeHint;
+    qreal maxWidth;
+    qreal increment;
+    // warm up instruction cache
+    l->invalidate();
+    sizeHint.setSize(l->effectiveSizeHint(Qt::MinimumSize));
+    maxWidth = l->effectiveSizeHint(Qt::MaximumSize).width();
+    increment = (maxWidth - sizeHint.width()) / 100;
+    l->setGeometry(sizeHint);
+    // ...then measure...
+
+    QBENCHMARK {
+        l->invalidate();
+        for (qreal width = sizeHint.width(); width <= maxWidth; width += increment) {
+            sizeHint.setWidth(width);
+            l->setGeometry(sizeHint);
+        }
+    }
+}
+
 void tst_QGraphicsAnchorLayout::linearVsAnchorNested_data()
 {
     QTest::addColumn<int>("whichLayout");
-- 
cgit v0.12


From 7644b352297e9fd1ee271421e9ce8b7256946b12 Mon Sep 17 00:00:00 2001
From: Gabriel de Dietrich <gabriel.dietrich-de@nokia.com>
Date: Fri, 16 Oct 2009 09:34:38 +0200
Subject: Fixed typo in qtableview.cpp.

Auto-test included. Will timeout on fail.

Reviewed-by: Alexis
---
 src/gui/itemviews/qtableview.cpp         |  2 +-
 tests/auto/qtableview/tst_qtableview.cpp | 35 +++++++++++++++++++++++++++-----
 2 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/src/gui/itemviews/qtableview.cpp b/src/gui/itemviews/qtableview.cpp
index a610b73..2a937f1 100644
--- a/src/gui/itemviews/qtableview.cpp
+++ b/src/gui/itemviews/qtableview.cpp
@@ -1599,7 +1599,7 @@ QModelIndex QTableView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifi
                 break;
             visualColumn = right + 1;
             if (visualRow == 0) {
-                wrapped == true;
+                wrapped = true;
                 visualRow = bottom;
             } else {
                 --visualRow;
diff --git a/tests/auto/qtableview/tst_qtableview.cpp b/tests/auto/qtableview/tst_qtableview.cpp
index d75cfa7..d8110e1 100644
--- a/tests/auto/qtableview/tst_qtableview.cpp
+++ b/tests/auto/qtableview/tst_qtableview.cpp
@@ -1195,6 +1195,13 @@ void tst_QTableView::moveCursorStrikesBack_data()
             << 0 << 5 << (IntList() << int(QtTestTableView::MoveNext))
             << 1 << 0;
 
+    QTest::newRow("Last column disabled. Task QTBUG-3878") << -1 << -1
+            << IntList()
+            << (IntList() << 6)
+            << QRect()
+            << 1 << 0 << (IntList() << int(QtTestTableView::MovePrevious))
+            << 0 << 5;
+
     QTest::newRow("Span, anchor column hidden") << -1 << 1
             << IntList()
             << IntList()
@@ -1250,6 +1257,24 @@ void tst_QTableView::moveCursorStrikesBack_data()
             << QRect(1, 2, 2, 3)
             << 5 << 2 << (IntList() << int(QtTestTableView::MoveUp) << int(QtTestTableView::MoveUp))
             << 1 << 2;
+
+    IntList fullList;
+    for (int i = 0; i < 7; ++i)
+        fullList << i;
+
+    QTest::newRow("All disabled, wrap forward. Timeout => FAIL") << -1 << -1
+            << fullList
+            << fullList
+            << QRect()
+            << 1 << 0 << (IntList() << int(QtTestTableView::MoveNext))
+            << 1 << 0;
+
+    QTest::newRow("All disabled, wrap backwards. Timeout => FAIL") << -1 << -1
+            << fullList
+            << fullList
+            << QRect()
+            << 1 << 0 << (IntList() << int(QtTestTableView::MovePrevious))
+            << 1 << 0;
 }
 
 void tst_QTableView::moveCursorStrikesBack()
@@ -1272,11 +1297,6 @@ void tst_QTableView::moveCursorStrikesBack()
     view.hideRow(hideRow);
     view.hideColumn(hideColumn);
 
-    foreach (int row, disableRows)
-        model.disableRow(row);
-    foreach (int column, disableColumns)
-        model.disableColumn(column);
-
     if (span.height() && span.width())
         view.setSpan(span.top(), span.left(), span.height(), span.width());
     view.show();
@@ -1284,6 +1304,11 @@ void tst_QTableView::moveCursorStrikesBack()
     QModelIndex index = model.index(startRow, startColumn);
     view.setCurrentIndex(index);
 
+    foreach (int row, disableRows)
+        model.disableRow(row);
+    foreach (int column, disableColumns)
+        model.disableColumn(column);
+
     int newRow = -1;
     int newColumn = -1;
     foreach (int cursorMoveAction, cursorMoveActions) {
-- 
cgit v0.12


From 7e5724b7d4632899af2e84856dd7d6f2a1771ee0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Arve=20S=C3=A6ther?= <jan-arve.saether@nokia.com>
Date: Fri, 16 Oct 2009 11:56:08 +0200
Subject: Make sure that the anchor layout autotests pass in release
 configuration

The problem was that lastCalculationUsedSimplex was only compiled in
debug mode. The autotests run in release, so it did not compile.

Reviewed-by: alexis
---
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp | 2 +-
 src/gui/graphicsview/qgraphicsanchorlayout_p.h   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index c9821ae..5a531f5 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -1781,7 +1781,7 @@ bool QGraphicsAnchorLayoutPrivate::calculateTrunk(Orientation orientation, const
         sizeAtExpanding[orientation] = ad->sizeAtExpanding;
     }
 
-#ifdef QT_DEBUG
+#if defined(QT_DEBUG) || defined(Q_AUTOTEST_EXPORT)
     lastCalculationUsedSimplex[orientation] = needsSimplex;
 #endif
 
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index d96a035..3a23677 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -523,7 +523,7 @@ public:
     bool graphHasConflicts[2];
     QSet<QGraphicsLayoutItem *> m_floatItems[2];
 
-#ifdef QT_DEBUG
+#if defined(QT_DEBUG) || defined(Q_AUTOTEST_EXPORT)
     bool lastCalculationUsedSimplex[2];
 #endif
 
-- 
cgit v0.12


From 6018d7a21a1ba336a59e3cda161b7cfeb144b4b5 Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Fri, 16 Oct 2009 16:31:27 +0200
Subject: Kill warning, simplify code.

Reviewed-by: TrustMe
---
 src/3rdparty/phonon/mmf/audiooutput.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/3rdparty/phonon/mmf/audiooutput.cpp b/src/3rdparty/phonon/mmf/audiooutput.cpp
index 5a00f60..bb0e5bc 100644
--- a/src/3rdparty/phonon/mmf/audiooutput.cpp
+++ b/src/3rdparty/phonon/mmf/audiooutput.cpp
@@ -102,15 +102,17 @@ bool MMF::AudioOutput::activateOnMediaObject(MediaObject *mo)
 
 QHash<QByteArray, QVariant> MMF::AudioOutput::audioOutputDescription(int index)
 {
+    QHash<QByteArray, QVariant> retval;
+
     if (index == AudioOutputDeviceID) {
         QHash<QByteArray, QVariant> retval;
 
         retval.insert("name", QCoreApplication::translate("Phonon::MMF", "Audio Output"));
         retval.insert("description", QCoreApplication::translate("Phonon::MMF", "The audio output device"));
         retval.insert("available", true);
-
-        return retval;
     }
+
+    return retval;
 }
 
 QT_END_NAMESPACE
-- 
cgit v0.12


From 299fd2c5d3c901890c0bc2c36c4b5f48d46859dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Arve=20S=C3=A6ther?= <jan-arve.saether@nokia.com>
Date: Fri, 16 Oct 2009 17:31:10 +0200
Subject: API addition: Make it possible to set the size policy of an anchor.

After this commit, when you modify the spacing of an anchor you are
effectively modifying the preferred size of the anchor, since all
anchors (except internal ones) have their minimumSizeHint to 0 and
maximumSizeHint to QWIDGETSIZE_MAX.

I also changed the sizeHintsFromItem to be more generic so that I could
use it for anchors. (Thus, it was renamed to "internalSizeHints"). It
now only takes care of setting the min/pref/exp/maxSize of AnchorData
based on the anchor/item size hint and their size policies.

As a consequence of all of this, setFixedSize changed behaviour and
became setPreferredSize (since setSpacing is basically setPreferredSize).
The implementation of that now only sets the prefSize.

The patch also has an unrelated fix for IgnoreFlag, where it will
(again) return the minimumSize for sizeHint(Qt::PreferredSize) instead
of the maximumSize. This was to be more consistent with
qgridlayoutengine.cpp. The docs are not very clear on this behaviour
unfortunately.

This API change has been discussed.

Reviewed-by: alexis
---
 src/gui/graphicsview/qgraphicsanchorlayout.cpp     |  17 ++++
 src/gui/graphicsview/qgraphicsanchorlayout.h       |   2 +
 src/gui/graphicsview/qgraphicsanchorlayout_p.cpp   | 109 ++++++++++++---------
 src/gui/graphicsview/qgraphicsanchorlayout_p.h     |  14 ++-
 .../tst_qgraphicsanchorlayout.cpp                  |  56 ++++++++---
 5 files changed, 130 insertions(+), 68 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout.cpp b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
index 9f4a19b..c39e8a6 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
@@ -118,6 +118,23 @@ QGraphicsAnchor::~QGraphicsAnchor()
 }
 
 /*!
+    Sets the size policy of the anchor to \a policy.
+*/
+void QGraphicsAnchor::setSizePolicy(QSizePolicy::Policy policy)
+{
+    Q_D(QGraphicsAnchor);
+    d->setSizePolicy(policy);
+}
+/*!
+    Returns the size policy of the anchor. The default size policy is QSizePolicy::Fixed
+*/
+QSizePolicy::Policy QGraphicsAnchor::sizePolicy() const
+{
+    Q_D(const QGraphicsAnchor);
+    return d->sizePolicy;
+}
+
+/*!
     \property QGraphicsAnchor::spacing
     \brief the space between items in the QGraphicsAnchorLayout.
 
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout.h b/src/gui/graphicsview/qgraphicsanchorlayout.h
index 99dbf92..f09ac43 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout.h
@@ -65,6 +65,8 @@ class Q_GUI_EXPORT QGraphicsAnchor : public QObject
 public:
     void setSpacing(qreal spacing);
     void unsetSpacing();
+    void setSizePolicy(QSizePolicy::Policy policy);
+    QSizePolicy::Policy sizePolicy() const;
     qreal spacing() const;
     ~QGraphicsAnchor();
 private:
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index e1db939..8c8c303 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -53,7 +53,8 @@ QT_BEGIN_NAMESPACE
 
 
 QGraphicsAnchorPrivate::QGraphicsAnchorPrivate(int version)
-    : QObjectPrivate(version), layoutPrivate(0), data(0)
+    : QObjectPrivate(version), layoutPrivate(0), data(0),
+      sizePolicy(QSizePolicy::Fixed)
 {
 }
 
@@ -62,6 +63,14 @@ QGraphicsAnchorPrivate::~QGraphicsAnchorPrivate()
     layoutPrivate->removeAnchor(data->from, data->to);
 }
 
+void QGraphicsAnchorPrivate::setSizePolicy(QSizePolicy::Policy policy)
+{
+    if (sizePolicy != policy) {
+        sizePolicy = policy;
+        layoutPrivate->q_func()->invalidate();
+    }
+}
+
 void QGraphicsAnchorPrivate::setSpacing(qreal value)
 {
     if (data) {
@@ -92,28 +101,11 @@ qreal QGraphicsAnchorPrivate::spacing() const
 }
 
 
-static void sizeHintsFromItem(QGraphicsLayoutItem *item,
-                             const QGraphicsAnchorLayoutPrivate::Orientation orient,
-                             qreal *minSize, qreal *prefSize,
-                             qreal *expSize, qreal *maxSize)
+static void internalSizeHints(QSizePolicy::Policy policy,
+                              qreal minSizeHint, qreal prefSizeHint, qreal maxSizeHint,
+                              qreal *minSize, qreal *prefSize,
+                              qreal *expSize, qreal *maxSize)
 {
-    QSizePolicy::Policy policy;
-    qreal minSizeHint;
-    qreal prefSizeHint;
-    qreal maxSizeHint;
-
-    if (orient == QGraphicsAnchorLayoutPrivate::Horizontal) {
-        policy = item->sizePolicy().horizontalPolicy();
-        minSizeHint = item->effectiveSizeHint(Qt::MinimumSize).width();
-        prefSizeHint = item->effectiveSizeHint(Qt::PreferredSize).width();
-        maxSizeHint = item->effectiveSizeHint(Qt::MaximumSize).width();
-    } else {
-        policy = item->sizePolicy().verticalPolicy();
-        minSizeHint = item->effectiveSizeHint(Qt::MinimumSize).height();
-        prefSizeHint = item->effectiveSizeHint(Qt::PreferredSize).height();
-        maxSizeHint = item->effectiveSizeHint(Qt::MaximumSize).height();
-    }
-
     // minSize, prefSize and maxSize are initialized
     // with item's preferred Size: this is QSizePolicy::Fixed.
     //
@@ -139,7 +131,7 @@ static void sizeHintsFromItem(QGraphicsLayoutItem *item,
 
     // Note that these two initializations are affected by the previous flags
     if (policy & QSizePolicy::IgnoreFlag)
-        *prefSize = *maxSize;
+        *prefSize = *minSize;
     else
         *prefSize = prefSizeHint;
 
@@ -153,38 +145,63 @@ void AnchorData::refreshSizeHints(qreal effectiveSpacing)
 {
     const bool isInternalAnchor = from->m_item == to->m_item;
 
+    QSizePolicy::Policy policy;
+    qreal minSizeHint;
+    qreal prefSizeHint;
+    qreal maxSizeHint;
+
     if (isInternalAnchor) {
         const QGraphicsAnchorLayoutPrivate::Orientation orient =
             QGraphicsAnchorLayoutPrivate::edgeOrientation(from->m_edge);
+        const Qt::AnchorPoint centerEdge =
+            QGraphicsAnchorLayoutPrivate::pickEdge(Qt::AnchorHorizontalCenter, orient);
+        bool hasCenter = (from->m_edge == centerEdge || to->m_edge == centerEdge);
 
         if (isLayoutAnchor) {
             minSize = 0;
             prefSize = 0;
             expSize = 0;
             maxSize = QWIDGETSIZE_MAX;
+            if (hasCenter)
+                maxSize /= 2;
+            return;
         } else {
-            QGraphicsLayoutItem *item = from->m_item;
-            sizeHintsFromItem(item, orient, &minSize, &prefSize, &expSize, &maxSize);
-        }
 
-        const Qt::AnchorPoint centerEdge =
-            QGraphicsAnchorLayoutPrivate::pickEdge(Qt::AnchorHorizontalCenter, orient);
-        bool hasCenter = (from->m_edge == centerEdge || to->m_edge == centerEdge);
+            QGraphicsLayoutItem *item = from->m_item;
+            if (orient == QGraphicsAnchorLayoutPrivate::Horizontal) {
+                policy = item->sizePolicy().horizontalPolicy();
+                minSizeHint = item->effectiveSizeHint(Qt::MinimumSize).width();
+                prefSizeHint = item->effectiveSizeHint(Qt::PreferredSize).width();
+                maxSizeHint = item->effectiveSizeHint(Qt::MaximumSize).width();
+            } else {
+                policy = item->sizePolicy().verticalPolicy();
+                minSizeHint = item->effectiveSizeHint(Qt::MinimumSize).height();
+                prefSizeHint = item->effectiveSizeHint(Qt::PreferredSize).height();
+                maxSizeHint = item->effectiveSizeHint(Qt::MaximumSize).height();
+            }
 
-        if (hasCenter) {
-            minSize /= 2;
-            prefSize /= 2;
-            expSize /= 2;
-            maxSize /= 2;
+            if (hasCenter) {
+                minSizeHint /= 2;
+                prefSizeHint /= 2;
+                maxSizeHint /= 2;
+            }
         }
-
-    } else if (!hasSize) {
-        // Anchor has no size defined, use given default information
-        minSize = effectiveSpacing;
-        prefSize = effectiveSpacing;
-        expSize = effectiveSpacing;
-        maxSize = effectiveSpacing;
+    } else {
+        Q_ASSERT(graphicsAnchor);
+        policy = graphicsAnchor->sizePolicy();
+        minSizeHint = 0;
+        if (hasSize) {
+            // One can only configure the preferred size of a normal anchor. Their minimum and
+            // maximum "size hints" are always 0 and QWIDGETSIZE_MAX, correspondingly. However,
+            // their effective size hints might be narrowed down due to their size policies.
+            prefSizeHint = prefSize;
+        } else {
+            prefSizeHint = effectiveSpacing;
+        }
+        maxSizeHint = QWIDGETSIZE_MAX;
     }
+    internalSizeHints(policy, minSizeHint, prefSizeHint, maxSizeHint, 
+                      &minSize, &prefSize, &expSize, &maxSize);
 
     // Set the anchor effective sizes to preferred.
     //
@@ -1191,18 +1208,18 @@ QGraphicsAnchor *QGraphicsAnchorLayoutPrivate::addAnchor(QGraphicsLayoutItem *fi
             || secondItem == q
             || pickEdge(firstEdge, Horizontal) == Qt::AnchorHorizontalCenter
             || oppositeEdge(firstEdge) != secondEdge) {
-            data->setFixedSize(0);
+            data->setPreferredSize(0);
         } else {
             data->unsetSize();
         }
         addAnchor_helper(firstItem, firstEdge, secondItem, secondEdge, data);
 
     } else if (*spacing >= 0) {
-        data->setFixedSize(*spacing);
+        data->setPreferredSize(*spacing);
         addAnchor_helper(firstItem, firstEdge, secondItem, secondEdge, data);
 
     } else {
-        data->setFixedSize(-*spacing);
+        data->setPreferredSize(-*spacing);
         addAnchor_helper(secondItem, secondEdge, firstItem, firstEdge, data);
     }
 
@@ -1389,9 +1406,9 @@ void QGraphicsAnchorLayoutPrivate::setAnchorSize(AnchorData *data, const qreal *
         // positive by definition.
         // "negative spacing" is handled by inverting the standard item order.
         if (*anchorSize >= 0) {
-            data->setFixedSize(*anchorSize);
+            data->setPreferredSize(*anchorSize);
         } else {
-            data->setFixedSize(-*anchorSize);
+            data->setPreferredSize(-*anchorSize);
             qSwap(data->from, data->to);
         }
     } else {
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 3a23677..d45c004 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -169,16 +169,9 @@ struct AnchorData : public QSimplexVariable {
     QString name;
 #endif
 
-    inline void setFixedSize(qreal size)
+    inline void setPreferredSize(qreal size)
     {
-        minSize = size;
         prefSize = size;
-        expSize = size;
-        maxSize = size;
-        sizeAtMinimum = size;
-        sizeAtPreferred = size;
-        sizeAtExpanding = size;
-        sizeAtMaximum = size;
         hasSize = true;
     }
 
@@ -316,8 +309,11 @@ public:
     void unsetSpacing();
     qreal spacing() const;
 
+    void setSizePolicy(QSizePolicy::Policy policy);
+
     QGraphicsAnchorLayoutPrivate *layoutPrivate;
     AnchorData *data;
+    QSizePolicy::Policy sizePolicy;
 };
 
 
@@ -528,6 +524,8 @@ public:
 #endif
 
     uint calculateGraphCacheDirty : 1;
+
+    friend class QGraphicsAnchorPrivate;
 };
 
 QT_END_NAMESPACE
diff --git a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
index cce7b4c..7b87969 100644
--- a/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
+++ b/tests/auto/qgraphicsanchorlayout/tst_qgraphicsanchorlayout.cpp
@@ -1296,19 +1296,8 @@ void tst_QGraphicsAnchorLayout::sizePolicy()
     l->setSpacing(0);
     l->setContentsMargins(0, 0, 0, 0);
 
-    // horizontal
-    QGraphicsAnchor *anchor = l->addAnchor(l, Qt::AnchorLeft, w1, Qt::AnchorLeft);
-    anchor->setSpacing(0);
-
-    anchor = l->addAnchor(w1, Qt::AnchorRight, l, Qt::AnchorRight);
-    anchor->setSpacing(0);
-
-    // vertical
-    anchor = l->addAnchor(l, Qt::AnchorTop, w1, Qt::AnchorTop);
-    anchor->setSpacing(0);
-
-    anchor = l->addAnchor(w1, Qt::AnchorBottom, l, Qt::AnchorBottom);
-    anchor->setSpacing(0);
+    // horizontal and vertical
+    l->addAnchors(l, w1);
 
     QGraphicsWidget *p = new QGraphicsWidget;
     p->setLayout(l);
@@ -1358,9 +1347,48 @@ void tst_QGraphicsAnchorLayout::sizePolicy()
     w1->adjustSize();
 
     QCOMPARE(l->effectiveSizeHint(Qt::MinimumSize), QSizeF(0, 0));
-    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(100, 100));
+    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(0, 0));
     QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(100, 100));
 
+    // Anchor size policies
+    w1->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    QGraphicsAnchor *anchor = l->anchor(l, Qt::AnchorLeft, w1, Qt::AnchorLeft);
+    anchor->setSpacing(10);
+
+    // QSizePolicy::Minimum
+    anchor->setSizePolicy(QSizePolicy::Minimum);
+    QApplication::processEvents();
+
+    QCOMPARE(l->effectiveSizeHint(Qt::MinimumSize), QSizeF(60, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(60, 50));
+    // The layout has a maximum size of QWIDGETSIZE_MAX, so the result won't exceed that value.
+    QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(QWIDGETSIZE_MAX, 50));
+
+    // QSizePolicy::Preferred
+    anchor->setSizePolicy(QSizePolicy::Preferred);
+    QApplication::processEvents();
+
+    QCOMPARE(l->effectiveSizeHint(Qt::MinimumSize), QSizeF(50, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(60, 50));
+    // The layout has a maximum size of QWIDGETSIZE_MAX, so the result won't exceed that value.
+    QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(QWIDGETSIZE_MAX, 50));
+
+    // QSizePolicy::Maximum
+    anchor->setSizePolicy(QSizePolicy::Maximum);
+    QApplication::processEvents();
+
+    QCOMPARE(l->effectiveSizeHint(Qt::MinimumSize), QSizeF(50, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(60, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(60, 50));
+
+    // QSizePolicy::Ignored
+    anchor->setSizePolicy(QSizePolicy::Ignored);
+    QApplication::processEvents();
+
+    QCOMPARE(l->effectiveSizeHint(Qt::MinimumSize), QSizeF(50, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::PreferredSize), QSizeF(50, 50));
+    QCOMPARE(l->effectiveSizeHint(Qt::MaximumSize), QSizeF(QWIDGETSIZE_MAX, 50));
+
     if (hasSimplification) {
         QVERIFY(!usedSimplex(l, Qt::Horizontal));
         QVERIFY(!usedSimplex(l, Qt::Vertical));
-- 
cgit v0.12


From 6f20e48d946fa3c90215f6affe5aa490559a6971 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Arve=20S=C3=A6ther?= <jan-arve.saether@nokia.com>
Date: Mon, 19 Oct 2009 09:25:12 +0200
Subject: Whitespace cleanup.

---
 src/gui/graphicsview/qgraphicsgridlayout.cpp | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/gui/graphicsview/qgraphicsgridlayout.cpp b/src/gui/graphicsview/qgraphicsgridlayout.cpp
index d1d91db..eef4e45 100644
--- a/src/gui/graphicsview/qgraphicsgridlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsgridlayout.cpp
@@ -63,7 +63,7 @@
     You can access each item in the layout by calling count() and itemAt(). Calling
     removeAt() will remove an item from the layout, without
     destroying it.
-    
+
     \sa QGraphicsLinearLayout, QGraphicsWidget
 */
 
@@ -89,7 +89,7 @@ public:
     QLayoutStyleInfo styleInfo() const;
 
     QGridLayoutEngine engine;
-#ifdef QT_DEBUG    
+#ifdef QT_DEBUG
     void dump(int indent) const;
 #endif
 };
@@ -121,7 +121,7 @@ QGraphicsGridLayout::~QGraphicsGridLayout()
     for (int i = count() - 1; i >= 0; --i) {
         QGraphicsLayoutItem *item = itemAt(i);
         // The following lines can be removed, but this removes the item
-        // from the layout more efficiently than the implementation of 
+        // from the layout more efficiently than the implementation of
         // ~QGraphicsLayoutItem.
         removeAt(i);
         if (item) {
@@ -141,18 +141,18 @@ void QGraphicsGridLayout::addItem(QGraphicsLayoutItem *item, int row, int column
 {
     Q_D(QGraphicsGridLayout);
     if (row < 0 || column < 0) {
-	qWarning("QGraphicsGridLayout::addItem: invalid row/column: %d",
-		 row < 0 ? row : column);
-	return;
+        qWarning("QGraphicsGridLayout::addItem: invalid row/column: %d",
+                 row < 0 ? row : column);
+        return;
     }
     if (columnSpan < 1 || rowSpan < 1) {
-	qWarning("QGraphicsGridLayout::addItem: invalid row span/column span: %d",
-		 rowSpan < 1 ? rowSpan : columnSpan);
-	return;
+        qWarning("QGraphicsGridLayout::addItem: invalid row span/column span: %d",
+                 rowSpan < 1 ? rowSpan : columnSpan);
+        return;
     }
     if (!item) {
-	qWarning("QGraphicsGridLayout::addItem: cannot add null item");
-	return;
+        qWarning("QGraphicsGridLayout::addItem: cannot add null item");
+        return;
     }
 
     d->addChildLayoutItem(item);
@@ -647,5 +647,5 @@ QSizePolicy::ControlTypes QGraphicsGridLayout::controlTypes(LayoutSide side) con
 #endif
 
 QT_END_NAMESPACE
-        
-#endif //QT_NO_GRAPHICSVIEW        
+
+#endif //QT_NO_GRAPHICSVIEW
-- 
cgit v0.12


From 856efef9bf87e0b7e5ed6ad2ccb225e294321888 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Arve=20S=C3=A6ther?= <jan-arve.saether@nokia.com>
Date: Mon, 19 Oct 2009 09:39:30 +0200
Subject: Do not loop forever if we are adding the layout itself to the layout.

Reviewed-by: alexis
---
 src/gui/graphicsview/qgraphicsgridlayout.cpp                  |  4 ++++
 src/gui/graphicsview/qgraphicslinearlayout.cpp                |  4 ++++
 tests/auto/qgraphicsgridlayout/tst_qgraphicsgridlayout.cpp    | 11 +++++++++++
 .../auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp  | 11 +++++++++++
 4 files changed, 30 insertions(+)

diff --git a/src/gui/graphicsview/qgraphicsgridlayout.cpp b/src/gui/graphicsview/qgraphicsgridlayout.cpp
index eef4e45..9a8dba0 100644
--- a/src/gui/graphicsview/qgraphicsgridlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsgridlayout.cpp
@@ -154,6 +154,10 @@ void QGraphicsGridLayout::addItem(QGraphicsLayoutItem *item, int row, int column
         qWarning("QGraphicsGridLayout::addItem: cannot add null item");
         return;
     }
+    if (item == this) {
+        qWarning("QGraphicsGridLayout::addItem: cannot insert itself");
+        return;
+    }
 
     d->addChildLayoutItem(item);
 
diff --git a/src/gui/graphicsview/qgraphicslinearlayout.cpp b/src/gui/graphicsview/qgraphicslinearlayout.cpp
index 0aa68df..7ff7c9b 100644
--- a/src/gui/graphicsview/qgraphicslinearlayout.cpp
+++ b/src/gui/graphicsview/qgraphicslinearlayout.cpp
@@ -272,6 +272,10 @@ void QGraphicsLinearLayout::insertItem(int index, QGraphicsLayoutItem *item)
         qWarning("QGraphicsLinearLayout::insertItem: cannot insert null item");
         return;
     }
+    if (item == this) {
+        qWarning("QGraphicsLinearLayout::insertItem: cannot insert itself");
+        return;
+    }
     d->addChildLayoutItem(item);
 
     Q_ASSERT(item);
diff --git a/tests/auto/qgraphicsgridlayout/tst_qgraphicsgridlayout.cpp b/tests/auto/qgraphicsgridlayout/tst_qgraphicsgridlayout.cpp
index 554292f..e33c7b6 100644
--- a/tests/auto/qgraphicsgridlayout/tst_qgraphicsgridlayout.cpp
+++ b/tests/auto/qgraphicsgridlayout/tst_qgraphicsgridlayout.cpp
@@ -104,6 +104,7 @@ private slots:
     void defaultStretchFactors();
     void geometries_data();
     void geometries();
+    void avoidRecursionInInsertItem();
     void task236367_maxSizeHint();
 };
 
@@ -2081,6 +2082,16 @@ void tst_QGraphicsGridLayout::geometries()
     delete widget;
 }
 
+void tst_QGraphicsGridLayout::avoidRecursionInInsertItem()
+{
+    QGraphicsWidget window(0, Qt::Window);
+	QGraphicsGridLayout *layout = new QGraphicsGridLayout(&window);
+    QCOMPARE(layout->count(), 0);
+    QTest::ignoreMessage(QtWarningMsg, "QGraphicsGridLayout::addItem: cannot insert itself");
+    layout->addItem(layout, 0, 0);
+    QCOMPARE(layout->count(), 0);
+}
+
 void tst_QGraphicsGridLayout::task236367_maxSizeHint()
 {
     QGraphicsWidget *widget = new QGraphicsWidget;
diff --git a/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp b/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
index 8e7bb45..546f92d 100644
--- a/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
+++ b/tests/auto/qgraphicslinearlayout/tst_qgraphicslinearlayout.cpp
@@ -101,6 +101,7 @@ private slots:
     void updateGeometry();
     void layoutDirection();
     void removeLayout();
+    void avoidRecursionInInsertItem();
 
     // Task specific tests
     void task218400_insertStretchCrash();
@@ -1432,6 +1433,16 @@ void tst_QGraphicsLinearLayout::removeLayout()
     QCOMPARE(pushButton->geometry(), r2);
 }
 
+void tst_QGraphicsLinearLayout::avoidRecursionInInsertItem()
+{
+    QGraphicsWidget window(0, Qt::Window);
+	QGraphicsLinearLayout *layout = new QGraphicsLinearLayout(&window);
+    QCOMPARE(layout->count(), 0);
+    QTest::ignoreMessage(QtWarningMsg, "QGraphicsLinearLayout::insertItem: cannot insert itself");
+    layout->insertItem(0, layout);
+    QCOMPARE(layout->count(), 0);
+}
+
 void tst_QGraphicsLinearLayout::task218400_insertStretchCrash()
 {
     QGraphicsScene *scene = new QGraphicsScene;
-- 
cgit v0.12


From 8472e256280f683f69fd5d9db5c2ed645dab6c92 Mon Sep 17 00:00:00 2001
From: axis <qt-info@nokia.com>
Date: Mon, 19 Oct 2009 10:27:18 +0200
Subject: Made sure the noSocketEvents value is preserved in case of exception.

Task:     QT-987
RevBy:    mread
---
 src/corelib/kernel/qeventdispatcher_symbian.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/corelib/kernel/qeventdispatcher_symbian.cpp b/src/corelib/kernel/qeventdispatcher_symbian.cpp
index 02f77a1..b32696d 100644
--- a/src/corelib/kernel/qeventdispatcher_symbian.cpp
+++ b/src/corelib/kernel/qeventdispatcher_symbian.cpp
@@ -668,6 +668,7 @@ void QEventDispatcherSymbian::closingDown()
 bool QEventDispatcherSymbian::processEvents ( QEventLoop::ProcessEventsFlags flags )
 {
     bool handledAnyEvent = false;
+    bool oldNoSocketEventsValue = m_noSocketEvents;
 
     QT_TRY {
         Q_D(QAbstractEventDispatcher);
@@ -686,7 +687,6 @@ bool QEventDispatcherSymbian::processEvents ( QEventLoop::ProcessEventsFlags fla
             block = false;
         }
 
-        bool oldNoSocketEventsValue = m_noSocketEvents;
         if (flags & QEventLoop::ExcludeSocketNotifiers) {
             m_noSocketEvents = true;
         } else {
@@ -762,14 +762,14 @@ bool QEventDispatcherSymbian::processEvents ( QEventLoop::ProcessEventsFlags fla
         };
 
         emit awake();
-
-        m_noSocketEvents = oldNoSocketEventsValue;
     } QT_CATCH (const std::exception& ex) {
 #ifndef QT_NO_EXCEPTIONS
         CActiveScheduler::Current()->Error(qt_symbian_exception2Error(ex));
 #endif
     }
 
+    m_noSocketEvents = oldNoSocketEventsValue;
+
     return handledAnyEvent;
 }
 
-- 
cgit v0.12


From 2e575432f1e1fd90e1f973791f2ee8df33b6e45e Mon Sep 17 00:00:00 2001
From: Markus Goetz <Markus.Goetz@nokia.com>
Date: Mon, 19 Oct 2009 10:42:42 +0200
Subject: QSslSocket: Also handle setSocketOption

Handle setSocketOption and forward it to the plainSocket that
QSslSocket is using internally.

Reviewed-by: Thiago
---
 src/network/socket/qabstractsocket.cpp | 13 +++++++++++++
 src/network/ssl/qsslsocket.cpp         | 16 ++++++++++++++++
 src/network/ssl/qsslsocket.h           |  4 ++++
 3 files changed, 33 insertions(+)

diff --git a/src/network/socket/qabstractsocket.cpp b/src/network/socket/qabstractsocket.cpp
index 86ccef2..9fb0b47 100644
--- a/src/network/socket/qabstractsocket.cpp
+++ b/src/network/socket/qabstractsocket.cpp
@@ -1578,6 +1578,13 @@ bool QAbstractSocket::setSocketDescriptor(int socketDescriptor, SocketState sock
 */
 void QAbstractSocket::setSocketOption(QAbstractSocket::SocketOption option, const QVariant &value)
 {
+#ifndef QT_NO_OPENSSL
+    if (QSslSocket *sslSocket = qobject_cast<QSslSocket*>(this)) {
+        sslSocket->setSocketOption(option, value);
+        return;
+    }
+#endif
+
     if (!d_func()->socketEngine)
         return;
 
@@ -1600,6 +1607,12 @@ void QAbstractSocket::setSocketOption(QAbstractSocket::SocketOption option, cons
 */
 QVariant QAbstractSocket::socketOption(QAbstractSocket::SocketOption option)
 {
+#ifndef QT_NO_OPENSSL
+    if (QSslSocket *sslSocket = qobject_cast<QSslSocket*>(this)) {
+        return sslSocket->socketOption(option);
+    }
+#endif
+
     if (!d_func()->socketEngine)
         return QVariant();
 
diff --git a/src/network/ssl/qsslsocket.cpp b/src/network/ssl/qsslsocket.cpp
index a5732fb..ad766c1 100644
--- a/src/network/ssl/qsslsocket.cpp
+++ b/src/network/ssl/qsslsocket.cpp
@@ -467,6 +467,22 @@ bool QSslSocket::setSocketDescriptor(int socketDescriptor, SocketState state, Op
     return retVal;
 }
 
+void QSslSocket::setSocketOption(QAbstractSocket::SocketOption option, const QVariant &value)
+{
+    Q_D(QSslSocket);
+    if (d->plainSocket)
+        d->plainSocket->setSocketOption(option, value);
+}
+
+QVariant QSslSocket::socketOption(QAbstractSocket::SocketOption option)
+{
+    Q_D(QSslSocket);
+    if (d->plainSocket)
+        return d->plainSocket->socketOption(option);
+    else
+        return QVariant();
+}
+
 /*!
     Returns the current mode for the socket; either UnencryptedMode, where
     QSslSocket behaves identially to QTcpSocket, or one of SslClientMode or
diff --git a/src/network/ssl/qsslsocket.h b/src/network/ssl/qsslsocket.h
index a41e600..adb206c 100644
--- a/src/network/ssl/qsslsocket.h
+++ b/src/network/ssl/qsslsocket.h
@@ -90,6 +90,10 @@ public:
     bool setSocketDescriptor(int socketDescriptor, SocketState state = ConnectedState,
                              OpenMode openMode = ReadWrite);
 
+    // ### Qt 5: Make virtual
+    void setSocketOption(QAbstractSocket::SocketOption option, const QVariant &value);
+    QVariant socketOption(QAbstractSocket::SocketOption option);
+
     SslMode mode() const;
     bool isEncrypted() const;
 
-- 
cgit v0.12


From f9e46cdb2d9a42d52f90fe50a53a76c03065b9ce Mon Sep 17 00:00:00 2001
From: David Faure <faure@kde.org>
Date: Mon, 19 Oct 2009 13:24:21 +0200
Subject: Fix crash in QPixmapCache.

QCache destruction accesses the key array that was freed in the QPixmapCache destruction, so better clear() before deleting that key.

Merge-request: 1820
Reviewed-by: Alexis Menard <alexis.menard@nokia.com>
---
 src/gui/image/qpixmapcache.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/gui/image/qpixmapcache.cpp b/src/gui/image/qpixmapcache.cpp
index f12d397..b0b7d72 100644
--- a/src/gui/image/qpixmapcache.cpp
+++ b/src/gui/image/qpixmapcache.cpp
@@ -221,6 +221,7 @@ QPMCache::QPMCache()
 }
 QPMCache::~QPMCache()
 {
+    clear();
     free(keyArray);
 }
 
-- 
cgit v0.12


From 7a647e8c9efbbd46184bc4714159c82ae26be958 Mon Sep 17 00:00:00 2001
From: Jedrzej Nowacki <jedrzej.nowacki@nokia.com>
Date: Mon, 19 Oct 2009 12:40:38 +0200
Subject: Regression fix. Fix the hasUncaughtException() flag in debugger's
 event.

The QScriptEngine::hasUncaughtException() flag should be set to true if
returning from a JS function was caused by an exception. According to
documentation, the flag had to be accessible from the
QScriptEngineAgent::functionExit event.

New autotest was added.

Reviewed-by: Kent Hansen
---
 src/script/api/qscriptengine.cpp                   | 12 +++++--
 src/script/api/qscriptengine_p.h                   |  5 +++
 src/script/api/qscriptengineagent.cpp              |  2 ++
 src/script/api/qscriptvalue.h                      |  3 ++
 .../qscriptengineagent/tst_qscriptengineagent.cpp  | 38 ++++++++++++++++++++++
 5 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/src/script/api/qscriptengine.cpp b/src/script/api/qscriptengine.cpp
index b1f36be..360036a 100644
--- a/src/script/api/qscriptengine.cpp
+++ b/src/script/api/qscriptengine.cpp
@@ -2164,7 +2164,7 @@ QScriptValue QScriptEngine::evaluate(const QString &program, const QString &file
     if (debugger)
         debugger->evaluateStart(sourceId);
 
-    exec->clearException();
+    clearExceptions();
     JSC::DynamicGlobalObjectScope dynamicGlobalObjectScope(exec, exec->scopeChain()->globalObject());
 
     JSC::EvalExecutable executable(exec, source);
@@ -2381,7 +2381,7 @@ bool QScriptEngine::hasUncaughtException() const
 {
     Q_D(const QScriptEngine);
     JSC::ExecState* exec = d->globalExec();
-    return exec->hadException();
+    return exec->hadException() || d->currentException().isValid();
 }
 
 /*!
@@ -2398,8 +2398,13 @@ bool QScriptEngine::hasUncaughtException() const
 QScriptValue QScriptEngine::uncaughtException() const
 {
     Q_D(const QScriptEngine);
+    QScriptValue result;
     JSC::ExecState* exec = d->globalExec();
-    return const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue(exec->exception());
+    if (exec->hadException())
+        result = const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue(exec->exception());
+    else
+        result = d->currentException();
+    return result;
 }
 
 /*!
@@ -2452,6 +2457,7 @@ void QScriptEngine::clearExceptions()
     Q_D(QScriptEngine);
     JSC::ExecState* exec = d->currentFrame;
     exec->clearException();
+    d->clearCurrentException();
 }
 
 /*!
diff --git a/src/script/api/qscriptengine_p.h b/src/script/api/qscriptengine_p.h
index f1fc135..cde116d 100644
--- a/src/script/api/qscriptengine_p.h
+++ b/src/script/api/qscriptengine_p.h
@@ -183,6 +183,10 @@ public:
 
     void agentDeleted(QScriptEngineAgent *agent);
 
+    void setCurrentException(QScriptValue exception) { m_currentException = exception; }
+    QScriptValue currentException() const { return m_currentException; }
+    void clearCurrentException() { m_currentException.d_ptr.reset(); }
+
 #ifndef QT_NO_QOBJECT
     JSC::JSValue newQObject(QObject *object,
         QScriptEngine::ValueOwnership ownership = QScriptEngine::QtOwnership,
@@ -263,6 +267,7 @@ public:
     QSet<QString> extensionsBeingImported;
     
     QHash<intptr_t, QScript::UStringSourceProviderWithFeedback*> loadedScripts;
+    QScriptValue m_currentException;
 
 #ifndef QT_NO_QOBJECT
     QHash<QObject*, QScript::QObjectData*> m_qobjectData;
diff --git a/src/script/api/qscriptengineagent.cpp b/src/script/api/qscriptengineagent.cpp
index bc2eea2..0ca7ecc 100644
--- a/src/script/api/qscriptengineagent.cpp
+++ b/src/script/api/qscriptengineagent.cpp
@@ -156,6 +156,7 @@ void QScriptEngineAgentPrivate::exceptionThrow(const JSC::DebuggerCallFrame& fra
     QScriptValue value(engine->scriptValueFromJSCValue(frame.exception()));
     q_ptr->exceptionThrow(sourceID, value, hasHandler);
     engine->currentFrame = oldFrame;
+    engine->setCurrentException(value);
 };
 
 void QScriptEngineAgentPrivate::exceptionCatch(const JSC::DebuggerCallFrame& frame, intptr_t sourceID)
@@ -165,6 +166,7 @@ void QScriptEngineAgentPrivate::exceptionCatch(const JSC::DebuggerCallFrame& fra
     QScriptValue value(engine->scriptValueFromJSCValue(frame.exception()));
     q_ptr->exceptionCatch(sourceID, value);
     engine->currentFrame = oldFrame;
+    engine->clearCurrentException();
 }
 
 void QScriptEngineAgentPrivate::atStatement(const JSC::DebuggerCallFrame& frame, intptr_t sourceID, int lineno, int column)
diff --git a/src/script/api/qscriptvalue.h b/src/script/api/qscriptvalue.h
index 32f7a43..aba3327 100644
--- a/src/script/api/qscriptvalue.h
+++ b/src/script/api/qscriptvalue.h
@@ -70,6 +70,7 @@ typedef QList<QScriptValue> QScriptValueList;
 typedef double qsreal;
 
 class QScriptValuePrivate;
+class QScriptEnginePrivate;
 struct QScriptValuePrivatePointerDeleter;
 class Q_SCRIPT_EXPORT QScriptValue
 {
@@ -226,6 +227,8 @@ private:
     QExplicitlySharedDataPointer<QScriptValuePrivate> d_ptr;
 
     Q_DECLARE_PRIVATE(QScriptValue)
+
+    friend class QScriptEnginePrivate;
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(QScriptValue::ResolveFlags)
diff --git a/tests/auto/qscriptengineagent/tst_qscriptengineagent.cpp b/tests/auto/qscriptengineagent/tst_qscriptengineagent.cpp
index 283e489..82c8ccd 100644
--- a/tests/auto/qscriptengineagent/tst_qscriptengineagent.cpp
+++ b/tests/auto/qscriptengineagent/tst_qscriptengineagent.cpp
@@ -109,6 +109,7 @@ private slots:
     void extension_invoctaion();
     void extension();
     void isEvaluatingInExtension();
+    void hasUncaughtException();
 
 private:
     double m_testProperty;
@@ -2182,5 +2183,42 @@ void tst_QScriptEngineAgent::isEvaluatingInExtension()
     QVERIFY(spy->wasEvaluating);
 }
 
+class NewSpy :public QScriptEngineAgent
+{
+    bool m_result;
+public:
+  NewSpy(QScriptEngine* eng) : QScriptEngineAgent(eng), m_result(false) {}
+  void functionExit (qint64, const QScriptValue &scriptValue)
+  {
+      if (engine()->hasUncaughtException()) m_result = true;
+  }
+
+  bool isPass() { return m_result; }
+  void reset() { m_result =  false; }
+};
+
+void tst_QScriptEngineAgent::hasUncaughtException()
+{
+  QScriptEngine eng;
+  NewSpy* spy = new NewSpy(&eng);
+  eng.setAgent(spy);
+  QScriptValue scriptValue;
+
+  // Check unhandled exception.
+  eng.evaluate("function init () {Unknown.doSth ();}");
+  scriptValue = QScriptValue(eng.globalObject().property("init")).call();
+  QVERIFY(eng.hasUncaughtException());
+  QVERIFY2(spy->isPass(), "At least one of a functionExit event should set hasUncaughtException flag.");
+  spy->reset();
+
+  // Check catched exception.
+  eng.evaluate("function innerFoo() { throw new Error('ciao') }");
+  eng.evaluate("function foo() {try { innerFoo() } catch (e) {} }");
+  scriptValue = QScriptValue(eng.globalObject().property("foo")).call();
+  QVERIFY(!eng.hasUncaughtException());
+  QVERIFY2(spy->isPass(), "At least one of a functionExit event should set hasUncaughtException flag.");
+}
+
+
 QTEST_MAIN(tst_QScriptEngineAgent)
 #include "tst_qscriptengineagent.moc"
-- 
cgit v0.12


From f16fc0150fce1d78cc71c27c163baf45e8953aca Mon Sep 17 00:00:00 2001
From: Martin Smith <msmith@trolltech.com>
Date: Mon, 19 Oct 2009 13:50:24 +0200
Subject: qdoc3: Added the \qmlattachedproperty command.

It works just like the \qmlproperty command, except
that it puts the properties in a different section for
attached properties.
---
 tools/qdoc3/cppcodemarker.cpp | 19 +++++++++++++++++--
 tools/qdoc3/cppcodeparser.cpp | 23 +++++++++++++++++------
 tools/qdoc3/htmlgenerator.cpp |  6 +++---
 tools/qdoc3/node.cpp          | 14 ++++++++++----
 tools/qdoc3/node.h            | 11 +++++++++--
 5 files changed, 56 insertions(+), 17 deletions(-)

diff --git a/tools/qdoc3/cppcodemarker.cpp b/tools/qdoc3/cppcodemarker.cpp
index ed3d150..36293f8 100644
--- a/tools/qdoc3/cppcodemarker.cpp
+++ b/tools/qdoc3/cppcodemarker.cpp
@@ -1112,6 +1112,10 @@ QList<Section> CppCodeMarker::qmlSections(const QmlClassNode* qmlClassNode,
                                       "QML Properties",
                                       "property",
                                       "properties");
+	    FastSection qmlattachedproperties(qmlClassNode,
+                                              "QML Attached Properties",
+                                              "property",
+                                              "properties");
 	    FastSection qmlsignals(qmlClassNode,
                                 "QML Signals",
                                 "signal",
@@ -1128,7 +1132,11 @@ QList<Section> CppCodeMarker::qmlSections(const QmlClassNode* qmlClassNode,
                     NodeList::ConstIterator p = qpgn->childNodes().begin();
                     while (p != qpgn->childNodes().end()) {
                         if ((*p)->type() == Node::QmlProperty) {
-                            insert(qmlproperties,*p,style,Okay);
+                            const QmlPropertyNode* pn = static_cast<const QmlPropertyNode*>(*p);
+                            if (pn->isAttached())
+                                insert(qmlattachedproperties,*p,style,Okay);
+                            else
+                                insert(qmlproperties,*p,style,Okay);
                         }
                         ++p;
                     }
@@ -1142,17 +1150,23 @@ QList<Section> CppCodeMarker::qmlSections(const QmlClassNode* qmlClassNode,
                 ++c;
             }
 	    append(sections,qmlproperties);
+	    append(sections,qmlattachedproperties);
 	    append(sections,qmlsignals);
 	    append(sections,qmlmethods);
         }
         else if (style == Detailed) {
 	    FastSection qmlproperties(qmlClassNode,"QML Property Documentation");
+	    FastSection qmlattachedproperties(qmlClassNode,"QML Attached Property Documentation");
 	    FastSection qmlsignals(qmlClassNode,"QML Signal Documentation");
 	    FastSection qmlmethods(qmlClassNode,"QML Method Documentation");
 	    NodeList::ConstIterator c = qmlClassNode->childNodes().begin();
 	    while (c != qmlClassNode->childNodes().end()) {
                 if ((*c)->subType() == Node::QmlPropertyGroup) {
-		    insert(qmlproperties,*c,style,Okay);
+                    const QmlPropGroupNode* pgn = static_cast<const QmlPropGroupNode*>(*c);
+                    if (pgn->isAttached())
+                        insert(qmlattachedproperties,*c,style,Okay);
+                    else
+                        insert(qmlproperties,*c,style,Okay);
 	        }
                 else if ((*c)->type() == Node::QmlSignal) {
                     insert(qmlsignals,*c,style,Okay);
@@ -1163,6 +1177,7 @@ QList<Section> CppCodeMarker::qmlSections(const QmlClassNode* qmlClassNode,
 	        ++c;
 	    }
 	    append(sections,qmlproperties);
+	    append(sections,qmlattachedproperties);
 	    append(sections,qmlsignals);
 	    append(sections,qmlmethods);
         }
diff --git a/tools/qdoc3/cppcodeparser.cpp b/tools/qdoc3/cppcodeparser.cpp
index d93e24c..ad43b2b 100644
--- a/tools/qdoc3/cppcodeparser.cpp
+++ b/tools/qdoc3/cppcodeparser.cpp
@@ -88,6 +88,7 @@ QT_BEGIN_NAMESPACE
 #ifdef QDOC_QML
 #define COMMAND_QMLCLASS                Doc::alias("qmlclass")
 #define COMMAND_QMLPROPERTY             Doc::alias("qmlproperty")
+#define COMMAND_QMLATTACHEDPROPERTY     Doc::alias("qmlattachedproperty")
 #define COMMAND_QMLINHERITS             Doc::alias("inherits")
 #define COMMAND_QMLSIGNAL               Doc::alias("qmlsignal")
 #define COMMAND_QMLMETHOD               Doc::alias("qmlmethod")
@@ -482,6 +483,7 @@ QSet<QString> CppCodeParser::topicCommands()
                            << COMMAND_VARIABLE
                            << COMMAND_QMLCLASS
                            << COMMAND_QMLPROPERTY
+                           << COMMAND_QMLATTACHEDPROPERTY
                            << COMMAND_QMLSIGNAL
                            << COMMAND_QMLMETHOD;
 #else
@@ -759,32 +761,40 @@ bool CppCodeParser::splitQmlArg(const Doc& doc,
 /*!
   Process the topic \a command group with arguments \a args.
 
-  Currently, this function is called only for \e{qmlproperty}.
+  Currently, this function is called only for \e{qmlproperty}
+  and \e{qmlattachedproperty}.
  */
 Node *CppCodeParser::processTopicCommandGroup(const Doc& doc,
                                               const QString& command,
                                               const QStringList& args)
 {
     QmlPropGroupNode* qmlPropGroup = 0;
-    if (command == COMMAND_QMLPROPERTY) {
+    if ((command == COMMAND_QMLPROPERTY) ||
+        (command == COMMAND_QMLATTACHEDPROPERTY)) {
         QString type;
         QString element;
         QString property;
+        bool attached = (command == COMMAND_QMLATTACHEDPROPERTY);
         QStringList::ConstIterator arg = args.begin();
         if (splitQmlPropertyArg(doc,(*arg),type,element,property)) {
             Node* n = tre->findNode(QStringList(element),Node::Fake);
             if (n && n->subType() == Node::QmlClass) {
                 QmlClassNode* qmlClass = static_cast<QmlClassNode*>(n);
                 if (qmlClass)
-                    qmlPropGroup = new QmlPropGroupNode(qmlClass,property);
+                    qmlPropGroup = new QmlPropGroupNode(qmlClass,
+                                                        property,
+                                                        attached);
             }
         }
         if (qmlPropGroup) {
-            new QmlPropertyNode(qmlPropGroup,property,type);
+            new QmlPropertyNode(qmlPropGroup,property,type,attached);
             ++arg;
             while (arg != args.end()) {
                 if (splitQmlPropertyArg(doc,(*arg),type,element,property)) {
-                    new QmlPropertyNode(qmlPropGroup,property,type);
+                    new QmlPropertyNode(qmlPropGroup,
+                                        property,
+                                        type,
+                                        attached);
                 }
                 ++arg;
             }
@@ -1969,7 +1979,8 @@ bool CppCodeParser::matchDocsAndStuff()
                   There is a topic command. Process it.
                  */
 #ifdef QDOC_QML
-                if (topic == COMMAND_QMLPROPERTY) {
+                if ((topic == COMMAND_QMLPROPERTY) ||
+                    (topic == COMMAND_QMLATTACHEDPROPERTY)) {
                     Doc nodeDoc = doc;
                     Node *node = processTopicCommandGroup(nodeDoc,topic,args);
                     if (node != 0) {
diff --git a/tools/qdoc3/htmlgenerator.cpp b/tools/qdoc3/htmlgenerator.cpp
index c02dc2e..18c7916 100644
--- a/tools/qdoc3/htmlgenerator.cpp
+++ b/tools/qdoc3/htmlgenerator.cpp
@@ -1240,7 +1240,7 @@ void HtmlGenerator::generateClassLikeNode(const InnerNode *inner,
     generateHeader(title, inner, marker, true);
     generateTitle(title, subtitleText, SmallSubTitle, inner, marker);
 
-#ifdef QDOC_QML    
+#ifdef QDOC_QML
     if (classe && !classe->qmlElement().isEmpty()) {
         generateInstantiatedBy(classe,marker);
     }
@@ -3468,12 +3468,12 @@ QString HtmlGenerator::refForNode(const Node *node)
         }
         break;
     case Node::Property:
-#ifdef QDOC_QML        
+#ifdef QDOC_QML
     case Node::QmlProperty:
 #endif        
         ref = node->name() + "-prop";
         break;
-#ifdef QDOC_QML        
+#ifdef QDOC_QML
     case Node::QmlSignal:
         ref = node->name() + "-signal";
         break;
diff --git a/tools/qdoc3/node.cpp b/tools/qdoc3/node.cpp
index 558808f..49f2cc9 100644
--- a/tools/qdoc3/node.cpp
+++ b/tools/qdoc3/node.cpp
@@ -1158,8 +1158,12 @@ QString QmlClassNode::fileBase() const
   Constructor for the Qml property group node. \a parent is
   always a QmlClassNode. 
  */
-QmlPropGroupNode::QmlPropGroupNode(QmlClassNode* parent, const QString& name)
-    : FakeNode(parent, name, QmlPropertyGroup), isdefault(false)
+QmlPropGroupNode::QmlPropGroupNode(QmlClassNode* parent,
+                                   const QString& name,
+                                   bool attached)
+    : FakeNode(parent, name, QmlPropertyGroup),
+      isdefault(false),
+      att(attached)
 {
     // nothing.
 }
@@ -1169,11 +1173,13 @@ QmlPropGroupNode::QmlPropGroupNode(QmlClassNode* parent, const QString& name)
  */
 QmlPropertyNode::QmlPropertyNode(QmlPropGroupNode *parent,
                                  const QString& name,
-                                 const QString& type)
+                                 const QString& type,
+                                 bool attached)
     : LeafNode(QmlProperty, parent, name),
       dt(type),
       sto(Trool_Default),
-      des(Trool_Default)
+      des(Trool_Default),
+      att(attached)
 {
     // nothing.
 }
diff --git a/tools/qdoc3/node.h b/tools/qdoc3/node.h
index f933270..fed4ea1 100644
--- a/tools/qdoc3/node.h
+++ b/tools/qdoc3/node.h
@@ -369,15 +369,19 @@ class QmlClassNode : public FakeNode
 class QmlPropGroupNode : public FakeNode
 {
  public:
-    QmlPropGroupNode(QmlClassNode* parent, const QString& name);
+    QmlPropGroupNode(QmlClassNode* parent, 
+                     const QString& name,
+                     bool attached);
     virtual ~QmlPropGroupNode() { }
 
     const QString& element() const { return name(); }
     void setDefault() { isdefault = true; }
     bool isDefault() const { return isdefault; }
+    bool isAttached() const { return att; }
 
  private:
     bool    isdefault;
+    bool    att;
 };
 
 class QmlPropertyNode : public LeafNode
@@ -385,7 +389,8 @@ class QmlPropertyNode : public LeafNode
  public:
     QmlPropertyNode(QmlPropGroupNode* parent, 
                     const QString& name,
-                    const QString& type);
+                    const QString& type,
+                    bool attached);
     virtual ~QmlPropertyNode() { }
 
     void setDataType(const QString& dataType) { dt = dataType; }
@@ -396,6 +401,7 @@ class QmlPropertyNode : public LeafNode
     QString qualifiedDataType() const { return dt; }
     bool isStored() const { return fromTrool(sto,true); }
     bool isDesignable() const { return fromTrool(des,false); }
+    bool isAttached() const { return att; }
 
     const QString& element() const { return parent()->name(); }
 
@@ -408,6 +414,7 @@ class QmlPropertyNode : public LeafNode
     QString dt;
     Trool   sto;
     Trool   des;
+    bool    att;
 };
 
 class QmlSignalNode : public LeafNode
-- 
cgit v0.12


From 226d67e9077b908a128521a6bb763cf412fbe87e Mon Sep 17 00:00:00 2001
From: Gunnar Sletta <gunnar@trolltech.com>
Date: Mon, 19 Oct 2009 08:30:48 +0200
Subject: Fixed bad glyph rendering under cocoa

The positioning is still wrong, but now it at least the glyphs are ok

Reviewed-by: msorvig
---
 src/gui/painting/qtextureglyphcache.cpp |  7 ++++
 src/gui/text/qfontengine_mac.mm         | 62 ++++++++++++++++++++++++---------
 src/gui/text/qfontengine_p.h            |  3 +-
 3 files changed, 54 insertions(+), 18 deletions(-)

diff --git a/src/gui/painting/qtextureglyphcache.cpp b/src/gui/painting/qtextureglyphcache.cpp
index 25b6aba..9e5707d 100644
--- a/src/gui/painting/qtextureglyphcache.cpp
+++ b/src/gui/painting/qtextureglyphcache.cpp
@@ -230,7 +230,14 @@ void QImageTextureGlyphCache::createTextureData(int width, int height)
 int QImageTextureGlyphCache::glyphMargin() const
 {
 #ifdef Q_WS_MAC
+
+#ifdef QT_MAC_USE_COCOA
+    // For cocoa the margin is built into the glyph it seems..
+    return 0;
+#else
     return 2;
+#endif
+
 #else
     return m_type == QFontEngineGlyphCache::Raster_RGBMask ? 2 : 0;
 #endif
diff --git a/src/gui/text/qfontengine_mac.mm b/src/gui/text/qfontengine_mac.mm
index 758d8af..d11083f 100644
--- a/src/gui/text/qfontengine_mac.mm
+++ b/src/gui/text/qfontengine_mac.mm
@@ -119,6 +119,28 @@ OSStatus QMacFontPath::closePath(void *data)
 }
 
 
+
+void qmacfontengine_gamma_correct(QImage *image)
+{
+    extern uchar qt_pow_rgb_gamma[256];
+
+    // gamma correct the pixels back to linear color space...
+    int h = image->height();
+    int w = image->width();
+
+    for (int y=0; y<h; ++y) {
+        uint *pixels = (uint *) image->scanLine(y);
+        for (int x=0; x<w; ++x) {
+            uint p = pixels[x];
+            uint r = qt_pow_rgb_gamma[qRed(p)];
+            uint g = qt_pow_rgb_gamma[qGreen(p)];
+            uint b = qt_pow_rgb_gamma[qBlue(p)];
+            pixels[x] = (r << 16) | (g << 8) | b | 0xff000000;
+        }
+    }
+}
+
+
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 QCoreTextFontEngineMulti::QCoreTextFontEngineMulti(const ATSFontFamilyRef &, const ATSFontRef &atsFontRef, const QFontDef &fontDef, bool kerning)
     : QFontEngineMulti(0)
@@ -534,7 +556,7 @@ void QCoreTextFontEngine::addGlyphsToPath(glyph_t *glyphs, QFixedPoint *position
     }
 }
 
-QImage QCoreTextFontEngine::alphaMapForGlyph(glyph_t glyph)
+QImage QCoreTextFontEngine::imageForGlyph(glyph_t glyph, int margin, bool aa)
 {
     const glyph_metrics_t br = boundingBox(glyph);
     QImage im(qRound(br.width)+2, qRound(br.height)+2, QImage::Format_RGB32);
@@ -549,9 +571,10 @@ QImage QCoreTextFontEngine::alphaMapForGlyph(glyph_t glyph)
                                              8, im.bytesPerLine(), colorspace,
                                              cgflags);
     CGContextSetFontSize(ctx, fontDef.pixelSize);
-    CGContextSetShouldAntialias(ctx, fontDef.pointSize > qt_antialiasing_threshold
-				&& !(fontDef.styleStrategy & QFont::NoAntialias));
-    CGContextSetShouldSmoothFonts(ctx, false);
+    CGContextSetShouldAntialias(ctx, aa ||
+                                (fontDef.pointSize > qt_antialiasing_threshold
+                                 && !(fontDef.styleStrategy & QFont::NoAntialias)));
+    CGContextSetShouldSmoothFonts(ctx, aa);
     CGAffineTransform oldTextMatrix = CGContextGetTextMatrix(ctx);
     CGAffineTransform cgMatrix = CGAffineTransformMake(1, 0, 0, 1, 0, 0);
 
@@ -586,6 +609,13 @@ QImage QCoreTextFontEngine::alphaMapForGlyph(glyph_t glyph)
 
     CGContextRelease(ctx);
 
+    return im;
+}
+
+QImage QCoreTextFontEngine::alphaMapForGlyph(glyph_t glyph)
+{
+    QImage im = imageForGlyph(glyph, 0, false);
+
     QImage indexed(im.width(), im.height(), QImage::Format_Indexed8);
     QVector<QRgb> colors(256);
     for (int i=0; i<256; ++i)
@@ -605,6 +635,16 @@ QImage QCoreTextFontEngine::alphaMapForGlyph(glyph_t glyph)
     return indexed;
 }
 
+QImage QCoreTextFontEngine::alphaRGBMapForGlyph(glyph_t glyph, int margin, const QTransform &x)
+{
+    if (x.type() >= QTransform::TxScale)
+        return QFontEngine::alphaRGBMapForGlyph(glyph, margin, x);
+
+    QImage im = imageForGlyph(glyph, margin, true);
+    qmacfontengine_gamma_correct(&im);
+    return im;
+}
+
 void QCoreTextFontEngine::recalcAdvances(int numGlyphs, QGlyphLayout *glyphs, QTextEngine::ShaperFlags flags) const
 {
     Q_ASSERT(false);
@@ -1505,19 +1545,7 @@ QImage QFontEngineMac::alphaRGBMapForGlyph(glyph_t glyph, int margin, const QTra
         im = im.transformed(t);
     }
 
-    extern uchar qt_pow_rgb_gamma[256];
-
-    // gamma correct the pixels back to linear color space...
-    for (int y=0; y<im.height(); ++y) {
-        uint *pixels = (uint *) im.scanLine(y);
-        for (int x=0; x<im.width(); ++x) {
-            uint p = pixels[x];
-            uint r = qt_pow_rgb_gamma[qRed(p)];
-            uint g = qt_pow_rgb_gamma[qGreen(p)];
-            uint b = qt_pow_rgb_gamma[qBlue(p)];
-            pixels[x] = (r << 16) | (g << 8) | b | 0xff000000;
-        }
-    }
+    qmacfontengine_gamma_correct(&im);
 
     return im;
 }
diff --git a/src/gui/text/qfontengine_p.h b/src/gui/text/qfontengine_p.h
index 50124fa..728c344 100644
--- a/src/gui/text/qfontengine_p.h
+++ b/src/gui/text/qfontengine_p.h
@@ -448,12 +448,13 @@ public:
     virtual bool getSfntTableData(uint /*tag*/, uchar * /*buffer*/, uint * /*length*/) const;
     virtual void getUnscaledGlyph(glyph_t glyph, QPainterPath *path, glyph_metrics_t *metrics);
     virtual QImage alphaMapForGlyph(glyph_t);
+    virtual QImage alphaRGBMapForGlyph(glyph_t, int margin, const QTransform &t);
     virtual qreal minRightBearing() const;
     virtual qreal minLeftBearing() const;
 
 
-
 private:
+    QImage imageForGlyph(glyph_t glyph, int margin, bool colorful);
     CTFontRef ctfont;
     CGFontRef cgFont;
     QCoreTextFontEngineMulti *parentEngine;
-- 
cgit v0.12


From 29ac4be932417880e06febddc23f7f930a790b1b Mon Sep 17 00:00:00 2001
From: Peter Hartmann <peter.hartmann@nokia.com>
Date: Mon, 19 Oct 2009 13:57:15 +0200
Subject: QTestLib: do not assert if file is not given in logging function

that assert was triggered when running a test with "-vs" to show all the
signals emitted.

Reviewed-by: Andy Shaw
---
 src/testlib/qtestlog.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/testlib/qtestlog.cpp b/src/testlib/qtestlog.cpp
index d96755a..5b78976 100644
--- a/src/testlib/qtestlog.cpp
+++ b/src/testlib/qtestlog.cpp
@@ -319,7 +319,6 @@ void QTestLog::info(const char *msg, const char *file, int line)
 {
     QTEST_ASSERT(QTest::testLogger);
     QTEST_ASSERT(msg);
-    QTEST_ASSERT(file);
 
     QTest::testLogger->addMessage(QAbstractTestLogger::Info, msg, file, line);
 }
-- 
cgit v0.12


From 09df1c7c0ebb944f2581779d2e029c16014ddec1 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Mon, 19 Oct 2009 07:23:20 +0200
Subject: setcepaths: add support for wincewm65professional-msvc200? mkspecs

Reviewed-by: mauricek
---
 bin/setcepaths.bat | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/bin/setcepaths.bat b/bin/setcepaths.bat
index 15d8ff8..914e594 100755
--- a/bin/setcepaths.bat
+++ b/bin/setcepaths.bat
@@ -79,6 +79,11 @@ checksdk.exe -sdk "Windows Mobile 6 Professional SDK (ARMV4I)" -script tmp_creat
 tmp_created_script_setup.bat
 del tmp_created_script_setup.bat
 echo Windows Mobile 6 Professional selected, environment is set up
+) ELSE IF "%1" EQU "wincewm65professional-msvc2005" (
+checksdk.exe -sdk "Windows Mobile 6 Professional SDK (ARMV4I)" -script tmp_created_script_setup.bat 1>NUL
+tmp_created_script_setup.bat
+del tmp_created_script_setup.bat
+echo Windows Mobile 6 Professional selected, environment is set up
 ) ELSE IF "%1" EQU "wincewm60standard-msvc2005" (
 checksdk.exe -sdk "Windows Mobile 6 Standard SDK (ARMV4I)" -script tmp_created_script_setup.bat 1>NUL
 tmp_created_script_setup.bat
@@ -124,6 +129,11 @@ checksdk.exe -sdk "Windows Mobile 6 Professional SDK (ARMV4I)" -script tmp_creat
 tmp_created_script_setup.bat
 del tmp_created_script_setup.bat
 echo Windows Mobile 6 Professional selected, environment is set up
+) ELSE IF "%1" EQU "wincewm65professional-msvc2008" (
+checksdk.exe -sdk "Windows Mobile 6 Professional SDK (ARMV4I)" -script tmp_created_script_setup.bat 1>NUL
+tmp_created_script_setup.bat
+del tmp_created_script_setup.bat
+echo Windows Mobile 6 Professional selected, environment is set up
 ) ELSE IF "%1" EQU "wincewm60standard-msvc2008" (
 checksdk.exe -sdk "Windows Mobile 6 Standard SDK (ARMV4I)" -script tmp_created_script_setup.bat 1>NUL
 tmp_created_script_setup.bat
-- 
cgit v0.12


From 5c2ed0f727aa300f70d1a50ce74ad1f0e7649dc1 Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Mon, 19 Oct 2009 15:42:36 +0300
Subject: Fixed QWidget::raise in Symbian

If toplevel window is raised, the whole application is now raised to
foreground.

Task-number: QT-2162
Reviewed-by: axis
---
 src/gui/kernel/qwidget_s60.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/gui/kernel/qwidget_s60.cpp b/src/gui/kernel/qwidget_s60.cpp
index 8ce5001..abf5ba5 100644
--- a/src/gui/kernel/qwidget_s60.cpp
+++ b/src/gui/kernel/qwidget_s60.cpp
@@ -550,8 +550,13 @@ void QWidgetPrivate::raise_sys()
     Q_Q(QWidget);
 
     Q_ASSERT(q->testAttribute(Qt::WA_WState_Created));
-    if (q->internalWinId())
+    if (q->internalWinId()) {
         q->internalWinId()->DrawableWindow()->SetOrdinalPosition(0);
+
+        // If toplevel widget, raise app to foreground
+        if (q->isWindow())
+            S60->wsSession().SetWindowGroupOrdinalPosition(S60->windowGroup().Identifier(), 0);
+    }
 }
 
 void QWidgetPrivate::lower_sys()
-- 
cgit v0.12


From 2955086c8d588e58cbfb808ee45212d5ec196b58 Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Mon, 19 Oct 2009 15:46:35 +0300
Subject: Fluidlauncher now comes to foreground when child application dies.

Task-number: QT-2162
Reviewed-by: axis
---
 demos/embedded/fluidlauncher/fluidlauncher.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/demos/embedded/fluidlauncher/fluidlauncher.cpp b/demos/embedded/fluidlauncher/fluidlauncher.cpp
index c065bc9..5e8cc03 100644
--- a/demos/embedded/fluidlauncher/fluidlauncher.cpp
+++ b/demos/embedded/fluidlauncher/fluidlauncher.cpp
@@ -265,6 +265,10 @@ void FluidLauncher::demoFinished()
 {
     setCurrentWidget(pictureFlowWidget);
     inputTimer->start();
+
+    // Bring the Fluidlauncher to the foreground to allow selecting another demo
+    raise();
+    activateWindow();
 }
 
 void FluidLauncher::changeEvent(QEvent* event)
-- 
cgit v0.12


From dbf8da3f2e56c13a3edf0cd89a3a8596df298e29 Mon Sep 17 00:00:00 2001
From: axis <qt-info@nokia.com>
Date: Mon, 19 Oct 2009 14:50:49 +0200
Subject: Fixed the build for people who only have emulator binaries installed

RevBy:    mread
---
 mkspecs/features/symbian/stl.prf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mkspecs/features/symbian/stl.prf b/mkspecs/features/symbian/stl.prf
index 8892d2a..e21ee5c 100644
--- a/mkspecs/features/symbian/stl.prf
+++ b/mkspecs/features/symbian/stl.prf
@@ -15,7 +15,7 @@ INCLUDEPATH += $$OS_LAYER_STDCPP_SYSTEMINCLUDE
 INCLUDEPATH -= $$[QT_INSTALL_PREFIX]/mkspecs/common/symbian/stl-off
 
 # libstdcppv5 is preferred over libstdcpp as it has/uses the throwing version of operator new
-exists($${EPOCROOT}epoc32/release/armv5/urel/libstdcppv5.dll ) {
+exists($${EPOCROOT}epoc32/release/armv5/urel/libstdcppv5.dll)|exists($${EPOCROOT}epoc32/release/winscw/udeb/libstdcppv5.dll) {
     LIBS *= -llibstdcppv5.dll
 
     # STDCPP turns on standard C++ new behaviour (ie. throwing new)
-- 
cgit v0.12


From e903578b7c970dd730b73a7eac711d812fefc43e Mon Sep 17 00:00:00 2001
From: Jason Barron <jbarron@trolltech.com>
Date: Mon, 19 Oct 2009 15:39:39 +0200
Subject: Fix doc error.

Should *not* be used as a softkey.

Reviewed-by: TrustMe
---
 src/gui/kernel/qaction.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gui/kernel/qaction.cpp b/src/gui/kernel/qaction.cpp
index 6a6e549..5f5650f 100644
--- a/src/gui/kernel/qaction.cpp
+++ b/src/gui/kernel/qaction.cpp
@@ -276,7 +276,7 @@ void QActionPrivate::setShortcutEnabled(bool enable, QShortcutMap &map)
     This enum describes how an action should be placed in the softkey bar. Currently this enum only
     has an effect on the Symbian platform.
 
-    \value NoSoftKey This action should be used as a softkey
+    \value NoSoftKey This action should not be used as a softkey
     \value PositiveSoftKey This action is used to describe a softkey with a positive or non-destructive
            role such as Ok, Select, or Options.
     \value NegativeSoftKey This action is used to describe a soft ey with a negative or destructive role
-- 
cgit v0.12


From a13cd1b97b352dc2e583b3d9b6254c7086218c3b Mon Sep 17 00:00:00 2001
From: Aleksandar Sasha Babic <aleksandar.babic@nokia.com>
Date: Mon, 19 Oct 2009 15:29:20 +0200
Subject: Reimplementing QDate/QTime/QDateTime in Symbian native manner

Some of the methods used in QDate/QTime/QDateTime have been
reimplemented to use native Symbian calls.

Reviewed-by: Janne Anttila
---
 src/corelib/tools/qdatetime.cpp | 62 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

diff --git a/src/corelib/tools/qdatetime.cpp b/src/corelib/tools/qdatetime.cpp
index 1b559cf..54465bb 100644
--- a/src/corelib/tools/qdatetime.cpp
+++ b/src/corelib/tools/qdatetime.cpp
@@ -73,6 +73,10 @@
 #include <private/qcore_mac_p.h>
 #endif
 
+#if defined(Q_OS_SYMBIAN)
+#include <e32std.h>
+#endif
+
 QT_BEGIN_NAMESPACE
 
 enum {
@@ -1128,6 +1132,12 @@ QDate QDate::currentDate()
     memset(&st, 0, sizeof(SYSTEMTIME));
     GetLocalTime(&st);
     d.jd = julianDayFromDate(st.wYear, st.wMonth, st.wDay);
+#elif defined(Q_OS_SYMBIAN)
+    TTime localTime;
+    localTime.HomeTime();
+    TDateTime localDateTime = localTime.DateTime();
+    // months and days are zero indexed
+    d.jd = julianDayFromDate(localDateTime.Year(), localDateTime.Month() + 1, localDateTime.Day() + 1 );
 #else
     // posix compliant system
     time_t ltime;
@@ -1823,6 +1833,12 @@ QTime QTime::currentTime()
 #if defined(Q_OS_WINCE)
     ct.startTick = GetTickCount() % MSECS_PER_DAY;
 #endif
+#elif defined(Q_OS_SYMBIAN)
+    TTime localTime;
+    localTime.HomeTime();
+    TDateTime localDateTime = localTime.DateTime();
+    ct.mds = MSECS_PER_HOUR * localDateTime.Hour() + MSECS_PER_MIN * localDateTime.Minute()
+                 + 1000 * localDateTime.Second() + (localDateTime.MicroSecond() / 1000);
 #elif defined(Q_OS_UNIX)
     // posix compliant system
     struct timeval tv;
@@ -2874,6 +2890,8 @@ QDateTime QDateTime::currentDateTime()
     t.mds = MSECS_PER_HOUR * st.wHour + MSECS_PER_MIN * st.wMinute + 1000 * st.wSecond
             + st.wMilliseconds;
     return QDateTime(d, t);
+#elif defined(Q_OS_SYMBIAN)
+    return QDateTime(QDate::currentDate(), QTime::currentTime());
 #else
 #if defined(Q_OS_UNIX)
     // posix compliant system
@@ -3700,6 +3718,27 @@ static QDateTimePrivate::Spec utcToLocal(QDate &date, QTime &time)
     res.tm_mon = sysTime.wMonth - 1;
     res.tm_year = sysTime.wYear - 1900;
     brokenDown = &res;
+#elif defined(Q_OS_SYMBIAN)
+    // months and days are zero index based
+    _LIT(KUnixEpoch, "19700000:000000.000000");
+    TTimeIntervalSeconds utcOffset = User::UTCOffset();
+    TTimeIntervalSeconds tTimeIntervalSecsSince1Jan1970UTC(secsSince1Jan1970UTC);
+    TTime epochTTime;
+    TInt err = epochTTime.Set(KUnixEpoch);
+    if(err == KErrNone) {
+        TTime utcTTime = epochTTime + tTimeIntervalSecsSince1Jan1970UTC;
+        utcTTime = utcTTime + utcOffset;
+        TDateTime utcDateTime = utcTTime.DateTime();
+        tm res;
+        res.tm_sec = utcDateTime.Second();
+        res.tm_min = utcDateTime.Minute();
+        res.tm_hour = utcDateTime.Hour();
+        res.tm_mday = utcDateTime.Day() + 1; // non-zero based index for tm struct
+        res.tm_mon = utcDateTime.Month();
+        res.tm_year = utcDateTime.Year() - 1900;
+        res.tm_isdst = 0;
+        brokenDown = &res;
+    }
 #elif !defined(QT_NO_THREAD) && defined(_POSIX_THREAD_SAFE_FUNCTIONS)
     // use the reentrant version of localtime() where available
     tzset();
@@ -3745,7 +3784,7 @@ static void localToUtc(QDate &date, QTime &time, int isdst)
     localTM.tm_mon = fakeDate.month() - 1;
     localTM.tm_year = fakeDate.year() - 1900;
     localTM.tm_isdst = (int)isdst;
-#if defined(Q_OS_WINCE)
+#if defined(Q_OS_WINCE) || defined(Q_OS_SYMBIAN)
     time_t secsSince1Jan1970UTC = toTime_tHelper(fakeDate, time);
 #else
 #if defined(Q_OS_WIN)
@@ -3770,6 +3809,27 @@ static void localToUtc(QDate &date, QTime &time, int isdst)
     res.tm_year = sysTime.wYear - 1900;
     res.tm_isdst = (int)isdst;
     brokenDown = &res;
+#elif defined(Q_OS_SYMBIAN)
+    // months and days are zero index based
+    _LIT(KUnixEpoch, "19700000:000000.000000");
+    TTimeIntervalSeconds utcOffset = TTimeIntervalSeconds(0 - User::UTCOffset().Int());
+    TTimeIntervalSeconds tTimeIntervalSecsSince1Jan1970UTC(secsSince1Jan1970UTC);
+    TTime epochTTime;
+    TInt err = epochTTime.Set(KUnixEpoch);
+    if(err == KErrNone) {
+        TTime utcTTime = epochTTime + tTimeIntervalSecsSince1Jan1970UTC;
+        utcTTime = utcTTime + utcOffset;
+        TDateTime utcDateTime = utcTTime.DateTime();
+        tm res;
+        res.tm_sec = utcDateTime.Second();
+        res.tm_min = utcDateTime.Minute();
+        res.tm_hour = utcDateTime.Hour();
+        res.tm_mday = utcDateTime.Day() + 1; // non-zero based index for tm struct
+        res.tm_mon = utcDateTime.Month();
+        res.tm_year = utcDateTime.Year() - 1900;
+        res.tm_isdst = (int)isdst;
+        brokenDown = &res;
+    }
 #elif !defined(QT_NO_THREAD) && defined(_POSIX_THREAD_SAFE_FUNCTIONS)
     // use the reentrant version of gmtime() where available
     tm res;
-- 
cgit v0.12


From f9d36789b4f2565f342f22d62a5106e5d5ca3389 Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Mon, 19 Oct 2009 12:04:57 +0200
Subject: Does not disable full screen when end of video playlist is reached.

Tested on Symbian and Windows(DS9).

Task-number: QTBUG-4869
Reviewed-by: Gareth Stockwell
---
 demos/qmediaplayer/mediaplayer.cpp          | 3 +++
 src/3rdparty/phonon/mmf/mmf_videoplayer.cpp | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/demos/qmediaplayer/mediaplayer.cpp b/demos/qmediaplayer/mediaplayer.cpp
index baac236..e1ceb0e 100644
--- a/demos/qmediaplayer/mediaplayer.cpp
+++ b/demos/qmediaplayer/mediaplayer.cpp
@@ -367,6 +367,9 @@ void MediaPlayer::stateChanged(Phonon::State newstate, Phonon::State oldstate)
         case Phonon::PausedState:
         case Phonon::StoppedState:
             playButton->setIcon(playIcon);
+
+            m_videoWidget->setFullScreen(false);
+
             if (m_MediaObject.currentSource().type() != Phonon::MediaSource::Invalid){
                 playButton->setEnabled(true);
                 rewindButton->setEnabled(true);
diff --git a/src/3rdparty/phonon/mmf/mmf_videoplayer.cpp b/src/3rdparty/phonon/mmf/mmf_videoplayer.cpp
index a93aca0..d1d2337 100644
--- a/src/3rdparty/phonon/mmf/mmf_videoplayer.cpp
+++ b/src/3rdparty/phonon/mmf/mmf_videoplayer.cpp
@@ -300,8 +300,8 @@ void MMF::VideoPlayer::MvpuoPlayComplete(TInt aError)
     TRACE_CONTEXT(VideoPlayer::MvpuoPlayComplete, EVideoApi)
     TRACE_ENTRY("state %d error %d", state(), aError);
 
-    // TODO
     Q_UNUSED(aError);   // suppress warnings in release builds
+    changeState(StoppedState);
 
     TRACE_EXIT_0();
 }
-- 
cgit v0.12


From ade25abbe4009c2f491cbd05e81903317d91ec82 Mon Sep 17 00:00:00 2001
From: Peter Hartmann <peter.hartmann@nokia.com>
Date: Mon, 19 Oct 2009 16:20:23 +0200
Subject: QTestLib: do not assert if testLogger object is already destroyed

... because when dumping signals we might get QThread::finished() etc.
when closing the program, and then the testLogger instance might
already be deleted.

Reviewed-by: Jesper
---
 src/testlib/qtestlog.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/testlib/qtestlog.cpp b/src/testlib/qtestlog.cpp
index 5b78976..da695dc 100644
--- a/src/testlib/qtestlog.cpp
+++ b/src/testlib/qtestlog.cpp
@@ -317,10 +317,10 @@ void QTestLog::warn(const char *msg)
 
 void QTestLog::info(const char *msg, const char *file, int line)
 {
-    QTEST_ASSERT(QTest::testLogger);
     QTEST_ASSERT(msg);
 
-    QTest::testLogger->addMessage(QAbstractTestLogger::Info, msg, file, line);
+    if (QTest::testLogger)
+        QTest::testLogger->addMessage(QAbstractTestLogger::Info, msg, file, line);
 }
 
 void QTestLog::setLogMode(LogMode mode)
-- 
cgit v0.12


From 758153a35e4f7066419f5a0a9f44cdc37839c419 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Mon, 19 Oct 2009 13:55:01 +0200
Subject: qwindowsmobilestyle.cpp: endif comment fixed

---
 src/gui/styles/qwindowsmobilestyle.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gui/styles/qwindowsmobilestyle.cpp b/src/gui/styles/qwindowsmobilestyle.cpp
index d27b1ec..a617102 100644
--- a/src/gui/styles/qwindowsmobilestyle.cpp
+++ b/src/gui/styles/qwindowsmobilestyle.cpp
@@ -6003,7 +6003,7 @@ void QWindowsMobileStyle::drawComplexControl(ComplexControl control, const QStyl
         }
         painter->restore();
         break;
-#endif // QT_NO_SLIDER
+#endif // QT_NO_SCROLLBAR
     case CC_ToolButton:
         if (const QStyleOptionToolButton *toolbutton
                 = qstyleoption_cast<const QStyleOptionToolButton *>(option)) {
-- 
cgit v0.12


From 3908a76b470632f943e836342591319b454d785b Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Mon, 19 Oct 2009 12:56:43 +0200
Subject: qwidget_wince.cpp: don't invalidate the crect on maximize

If we do this, QWidget::width() returns negative sizes, which makes
QGraphicsView crash.

Reviewed-by: thartman
---
 src/gui/kernel/qwidget_wince.cpp | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/src/gui/kernel/qwidget_wince.cpp b/src/gui/kernel/qwidget_wince.cpp
index 4a0d30c..0666ab8 100644
--- a/src/gui/kernel/qwidget_wince.cpp
+++ b/src/gui/kernel/qwidget_wince.cpp
@@ -474,7 +474,7 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
     int normal = SW_SHOWNOACTIVATE;
 
     if ((oldstate & Qt::WindowMinimized) && !(newstate & Qt::WindowMinimized))
-       newstate |= Qt::WindowActive;
+        newstate |= Qt::WindowActive;
     if (newstate & Qt::WindowActive)
         normal = SW_SHOWNORMAL;
     if (isWindow()) {
@@ -490,13 +490,13 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
                 d->topData()->normalGeometry = geometry();
         }
         if ((oldstate & Qt::WindowMaximized) != (newstate & Qt::WindowMaximized)) {
-             if (!(newstate & Qt::WindowMaximized)) {
+            if (!(newstate & Qt::WindowMaximized)) {
                 int style = GetWindowLong(internalWinId(), GWL_STYLE) | WS_BORDER | WS_POPUP | WS_CAPTION;
                 SetWindowLong(internalWinId(), GWL_STYLE, style);
                 SetWindowLong(internalWinId(), GWL_EXSTYLE, GetWindowLong (internalWinId(), GWL_EXSTYLE) & ~ WS_EX_NODRAG);
             }
-             if (isVisible() && newstate & Qt::WindowMaximized)
-                    qt_wince_maximize(this);
+            if (isVisible() && newstate & Qt::WindowMaximized)
+                qt_wince_maximize(this);
             if (isVisible() && !(newstate & Qt::WindowMinimized)) {
                 ShowWindow(internalWinId(), (newstate & Qt::WindowMaximized) ? max : normal);
                 if (!(newstate & Qt::WindowFullScreen)) {
@@ -560,16 +560,6 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
                 qt_wince_maximize(this);
             }
         }
-        if ((newstate & Qt::WindowMaximized) && !(newstate & Qt::WindowFullScreen)) {
-            QRect r = d->topData()->normalGeometry;
-#ifdef Q_WS_WINCE_WM
-            if (!inherits("QDialog") && !inherits("QMdiArea") && !isVisible()) {
-                d->data.crect.setRect(0, 0, -1, -1);
-            }
-#else
-            qt_wince_maximize(this);
-#endif
-        }
     }
     data->window_state = newstate;
     QWindowStateChangeEvent e(oldstate);
-- 
cgit v0.12


From 93a6da9a9b14bc2ff637c6756bbb467f58f6200b Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Mon, 19 Oct 2009 14:19:56 +0200
Subject: fix bug in tst_qwidget.cpp

WinIdChangeEventWidget::event didn't return a value in all codepaths.

Reviewed-by: thartman
---
 tests/auto/qwidget/tst_qwidget.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/tests/auto/qwidget/tst_qwidget.cpp b/tests/auto/qwidget/tst_qwidget.cpp
index 758821b..1b898f4 100644
--- a/tests/auto/qwidget/tst_qwidget.cpp
+++ b/tests/auto/qwidget/tst_qwidget.cpp
@@ -4362,11 +4362,13 @@ public:
 
     }
 protected:
-    bool event(QEvent *e){
-        if(e->type() == QEvent::WinIdChange)
+    bool event(QEvent *e)
+    {
+        if (e->type() == QEvent::WinIdChange) {
             ++m_winIdChangeEventCount;
-        else
-            return QWidget::event(e);
+            return true;
+        }
+        return QWidget::event(e);
     }
 public:
     int m_winIdChangeEventCount;
-- 
cgit v0.12


From 02c15e6a8cdb0f8a0bb6ee36880877fe90334d69 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Mon, 19 Oct 2009 14:44:43 +0200
Subject: fix widget activation from minimized state on Windows mobile

The following didn't work on Windows mobile:
   * show a widget normal (non-maximized)
   * minimize it
   * reactivate it via the file explorer
   * now the widget should be visible again

The code path from minimized to normal state was missing.

Reviewed-by: thartman
---
 src/gui/kernel/qwidget_wince.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/gui/kernel/qwidget_wince.cpp b/src/gui/kernel/qwidget_wince.cpp
index 0666ab8..2fe69e4 100644
--- a/src/gui/kernel/qwidget_wince.cpp
+++ b/src/gui/kernel/qwidget_wince.cpp
@@ -558,6 +558,8 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
             else if (newstate & Qt::WindowMaximized) {
                 ShowWindow(internalWinId(), max);
                 qt_wince_maximize(this);
+            } else {
+                ShowWindow(internalWinId(), normal);
             }
         }
     }
-- 
cgit v0.12


From 2633931653757decd93dd3939c09f5e07203da1c Mon Sep 17 00:00:00 2001
From: Orgad Shaneh <orgads@gmail.com>
Date: Mon, 19 Oct 2009 11:59:20 +0200
Subject: Fix a bug affecting keyboard navigation in the table view

Reviewed-by: thierry
Reviewed-by: pierre
---
 src/gui/itemviews/qlistview.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/itemviews/qlistview.cpp b/src/gui/itemviews/qlistview.cpp
index 243f542..1d9b6e0 100644
--- a/src/gui/itemviews/qlistview.cpp
+++ b/src/gui/itemviews/qlistview.cpp
@@ -1105,13 +1105,13 @@ QModelIndex QListView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifie
             ++row;
         if (row >= rowCount)
             return QModelIndex();
-        return d->model->index(row, 0, d->root);
+        return d->model->index(row, d->column, d->root);
     }
 
     const QRect initialRect = rectForIndex(current);
     QRect rect = initialRect;
     if (rect.isEmpty()) {
-        return d->model->index(0, 0, d->root);
+        return d->model->index(0, d->column, d->root);
     }
     if (d->gridSize().isValid()) rect.setSize(d->gridSize());
 
-- 
cgit v0.12


From 93550050f4fe4f411bfbd80d7b30ff5bc8a20df7 Mon Sep 17 00:00:00 2001
From: Pierre Rossi <pierre.rossi@nokia.com>
Date: Mon, 19 Oct 2009 21:37:45 +0200
Subject: add the autotest for the QListView::setModelColumn bug

sha1 of the fix: 2633931653757decd93dd3939c09f5e07203da1c
---
 tests/auto/qlistview/tst_qlistview.cpp | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/tests/auto/qlistview/tst_qlistview.cpp b/tests/auto/qlistview/tst_qlistview.cpp
index 7599ce6a06..3ee6889 100644
--- a/tests/auto/qlistview/tst_qlistview.cpp
+++ b/tests/auto/qlistview/tst_qlistview.cpp
@@ -116,6 +116,7 @@ private slots:
     void keyboardSearch();
     void shiftSelectionWithNonUniformItemSizes();
     void clickOnViewportClearsSelection();
+    void task262152_setModelColumnNavigate();
 };
 
 // Testing get/set functions
@@ -1767,6 +1768,29 @@ void tst_QListView::clickOnViewportClearsSelection()
 
 }
 
+void tst_QListView::task262152_setModelColumnNavigate()
+{
+    QListView view;
+    QStandardItemModel model(3,2);
+    model.setItem(0,1,new QStandardItem("[0,1]"));
+    model.setItem(1,1,new QStandardItem("[1,1]"));
+    model.setItem(2,1,new QStandardItem("[2,1]"));
+
+    view.setModel(&model);
+    view.setModelColumn(1);
+
+    view.show();
+    QTest::qWait(30);
+    QTest::keyClick(&view, Qt::Key_Down);
+    QTest::qWait(10);
+    QCOMPARE(view.currentIndex(), model.index(1,1));
+    QTest::keyClick(&view, Qt::Key_Down);
+    QTest::qWait(10);
+    QCOMPARE(view.currentIndex(), model.index(2,1));
+
+}
+
+
 
 QTEST_MAIN(tst_QListView)
 #include "tst_qlistview.moc"
-- 
cgit v0.12


From bbbb62552b1c0f68b960c1412c66b6381e7dd4d1 Mon Sep 17 00:00:00 2001
From: Rhys Weatherley <rhys.weatherley@nokia.com>
Date: Tue, 20 Oct 2009 09:00:02 +1000
Subject: Optimize QVGPixmapDropShadowFilter by removing colorize step

Previously, the drop shadow was colorizing the incoming
image and then blurring the colorized version.  This change
first blurs the image to an alpha-only VGImage and then uses
that VGImage as a stencil to draw the drop shadow color.

This way, there is only 1 filter step and a draw instead of
2 filter steps and a draw.  The result is to make the performance
of the drop shadow filter almost identical to the blur filter.

Reviewed-by: trustme
---
 src/openvg/qpaintengine_vg.cpp  | 18 ++++++++++++++
 src/openvg/qpixmapfilter_vg.cpp | 54 ++++++-----------------------------------
 src/openvg/qpixmapfilter_vg_p.h |  5 ----
 3 files changed, 25 insertions(+), 52 deletions(-)

diff --git a/src/openvg/qpaintengine_vg.cpp b/src/openvg/qpaintengine_vg.cpp
index fdd61ea..da07c1d 100644
--- a/src/openvg/qpaintengine_vg.cpp
+++ b/src/openvg/qpaintengine_vg.cpp
@@ -2872,6 +2872,24 @@ void qt_vg_drawVGImage(QPainter *painter, const QPointF& pos, VGImage vgImg)
     drawVGImage(engine->vgPrivate(), pos, vgImg);
 }
 
+// Used by qpixmapfilter_vg.cpp to draw filtered VGImage's as a stencil.
+void qt_vg_drawVGImageStencil
+    (QPainter *painter, const QPointF& pos, VGImage vgImg, const QBrush& brush)
+{
+    QVGPaintEngine *engine =
+        static_cast<QVGPaintEngine *>(painter->paintEngine());
+
+    QVGPaintEnginePrivate *d = engine->vgPrivate();
+
+    QTransform transform(d->imageTransform);
+    transform.translate(pos.x(), pos.y());
+    d->setTransform(VG_MATRIX_IMAGE_USER_TO_SURFACE, transform);
+
+    d->ensureBrush(brush);
+    d->setImageMode(VG_DRAW_IMAGE_STENCIL);
+    vgDrawImage(vgImg);
+}
+
 void QVGPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr)
 {
     QPixmapData *pd = pm.pixmapData();
diff --git a/src/openvg/qpixmapfilter_vg.cpp b/src/openvg/qpixmapfilter_vg.cpp
index 3305bbb..8e104db 100644
--- a/src/openvg/qpixmapfilter_vg.cpp
+++ b/src/openvg/qpixmapfilter_vg.cpp
@@ -58,6 +58,8 @@ QVGPixmapConvolutionFilter::~QVGPixmapConvolutionFilter()
 
 extern void qt_vg_drawVGImage
     (QPainter *painter, const QPointF& pos, VGImage vgImg);
+extern void qt_vg_drawVGImageStencil
+    (QPainter *painter, const QPointF& pos, VGImage vgImg, const QBrush& brush);
 
 void QVGPixmapConvolutionFilter::draw
         (QPainter *painter, const QPointF &dest,
@@ -213,8 +215,7 @@ void QVGPixmapColorizeFilter::draw(QPainter *painter, const QPointF &dest, const
 }
 
 QVGPixmapDropShadowFilter::QVGPixmapDropShadowFilter()
-    : QPixmapDropShadowFilter(),
-      firstTime(true)
+    : QPixmapDropShadowFilter()
 {
 }
 
@@ -238,49 +239,11 @@ void QVGPixmapDropShadowFilter::draw(QPainter *painter, const QPointF &dest, con
         return;
 
     QSize size = pd->size();
-    VGImage tmpImage = vgCreateImage
-        (VG_sARGB_8888_PRE, size.width(), size.height(),
-         VG_IMAGE_QUALITY_FASTER);
-    if (tmpImage == VG_INVALID_HANDLE)
-        return;
-
     VGImage dstImage = vgCreateImage
-        (VG_sARGB_8888_PRE, size.width(), size.height(),
+        (VG_A_8, size.width(), size.height(),
          VG_IMAGE_QUALITY_FASTER);
-    if (dstImage == VG_INVALID_HANDLE) {
-        vgDestroyImage(tmpImage);
+    if (dstImage == VG_INVALID_HANDLE)
         return;
-    }
-
-    // Recompute the color matrix if the color has changed.
-    QColor c = color();
-    if (c != prevColor || firstTime) {
-        prevColor = c;
-
-        matrix[0][0] = 0.0f;
-        matrix[0][1] = 0.0f;
-        matrix[0][2] = 0.0f;
-        matrix[0][3] = 0.0f;
-        matrix[1][0] = 0.0f;
-        matrix[1][1] = 0.0f;
-        matrix[1][2] = 0.0f;
-        matrix[1][3] = 0.0f;
-        matrix[2][0] = 0.0f;
-        matrix[2][1] = 0.0f;
-        matrix[2][2] = 0.0f;
-        matrix[2][3] = 0.0f;
-        matrix[3][0] = c.redF();
-        matrix[3][1] = c.greenF();
-        matrix[3][2] = c.blueF();
-        matrix[3][3] = c.alphaF();
-        matrix[4][0] = 0.0f;
-        matrix[4][1] = 0.0f;
-        matrix[4][2] = 0.0f;
-        matrix[4][3] = 0.0f;
-    }
-
-    // Blacken the source image.
-    vgColorMatrix(tmpImage, srcImage, matrix[0]);
 
     // Clamp the radius range.  We divide by 2 because the OpenVG blur
     // is "too blurry" compared to the default raster implementation.
@@ -292,9 +255,7 @@ void QVGPixmapDropShadowFilter::draw(QPainter *painter, const QPointF &dest, con
         radiusF = maxRadius;
 
     // Blur the blackened source image.
-    vgGaussianBlur(dstImage, tmpImage, radiusF, radiusF, VG_TILE_PAD);
-
-    firstTime = false;
+    vgGaussianBlur(dstImage, srcImage, radiusF, radiusF, VG_TILE_PAD);
 
     VGImage child = VG_INVALID_HANDLE;
 
@@ -308,11 +269,10 @@ void QVGPixmapDropShadowFilter::draw(QPainter *painter, const QPointF &dest, con
         child = vgChildImage(dstImage, srect.x(), srect.y(), srect.width(), srect.height());
     }
 
-    qt_vg_drawVGImage(painter, dest + offset(), child);
+    qt_vg_drawVGImageStencil(painter, dest + offset(), child, color());
 
     if(child != dstImage)
         vgDestroyImage(child);
-    vgDestroyImage(tmpImage);
     vgDestroyImage(dstImage);
 
     // Now draw the actual pixmap over the top.
diff --git a/src/openvg/qpixmapfilter_vg_p.h b/src/openvg/qpixmapfilter_vg_p.h
index f79b6c2..efbbc7b 100644
--- a/src/openvg/qpixmapfilter_vg_p.h
+++ b/src/openvg/qpixmapfilter_vg_p.h
@@ -89,11 +89,6 @@ public:
     ~QVGPixmapDropShadowFilter();
 
     void draw(QPainter *p, const QPointF &pos, const QPixmap &px, const QRectF &src) const;
-
-private:
-    mutable VGfloat matrix[5][4];
-    mutable QColor prevColor;
-    mutable bool firstTime;
 };
 
 class Q_OPENVG_EXPORT QVGPixmapBlurFilter : public QPixmapBlurFilter
-- 
cgit v0.12


From dfd6221d960ec8c563a687684000c3a9c4f58079 Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Tue, 20 Oct 2009 10:21:38 +1000
Subject: Misc mysql test fixes.

---
 tests/auto/qsqldatabase/tst_qsqldatabase.cpp | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/tests/auto/qsqldatabase/tst_qsqldatabase.cpp b/tests/auto/qsqldatabase/tst_qsqldatabase.cpp
index 13d68ff..82b6066 100644
--- a/tests/auto/qsqldatabase/tst_qsqldatabase.cpp
+++ b/tests/auto/qsqldatabase/tst_qsqldatabase.cpp
@@ -1072,17 +1072,20 @@ void tst_QSqlDatabase::recordMySQL()
     int revision = tst_Databases::getMySqlVersion( db ).section( QChar('.'), 2, 2 ).toInt();
     int vernum = (major << 16) + (minor << 8) + revision;
 
-#ifdef QT3_SUPPORT
     /* The below is broken in mysql below 5.0.15
         see http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html
         specifically: Before MySQL 5.0.15, the pad value is space. Values are right-padded
         with space on insert, and trailing spaces are removed on select.
     */
     if( vernum >= ((5 << 16) + 15) ) {
+#ifdef QT3_SUPPORT
         bin10 = FieldDef("binary(10)", QVariant::ByteArray, QByteArray(Q3CString("123abc    ")));
         varbin10 = FieldDef("varbinary(10)", QVariant::ByteArray, QByteArray(Q3CString("123abcv   ")));
-    }
+#else
+        bin10 = FieldDef("binary(10)", QVariant::ByteArray, QString("123abc    "));
+        varbin10 = FieldDef("varbinary(10)", QVariant::ByteArray, QString("123abcv   "));
 #endif
+    }
 
     static QDateTime dt(QDate::currentDate(), QTime(1, 2, 3, 0));
     static const FieldDef fieldDefs[] = {
@@ -2468,7 +2471,7 @@ void tst_QSqlDatabase::mysql_savepointtest()
     QFETCH(QString, dbName);
     QSqlDatabase db = QSqlDatabase::database(dbName);
     CHECK_DATABASE(db);
-    if ( db.driverName().startsWith( "QMYSQL" ) && tst_Databases::getMySqlVersion( db ).section( QChar('.'), 0, 1 ).toInt()<4.1 )
+    if ( db.driverName().startsWith( "QMYSQL" ) && tst_Databases::getMySqlVersion( db ).section( QChar('.'), 0, 1 ).toDouble()<4.1 )
         QSKIP( "Test requires MySQL >= 4.1", SkipSingle );
 
     QSqlQuery q(db);
-- 
cgit v0.12


From 420be4ee3d98c093c71cc840192138da6b5e61d2 Mon Sep 17 00:00:00 2001
From: Sarah Smith <sarah.j.smith@nokia.com>
Date: Tue, 20 Oct 2009 11:53:30 +1000
Subject: Fix bug QTBUG-4848

Make the shapeText function return numGlyphs properly - its not always
the same as length of string.

Task-number: QTBUG-4848
Reviewed-by: Rhys Weatherley
---
 src/gui/text/qfontengine_mac.mm  | 14 +++++++---
 src/gui/text/qtextengine_mac.cpp |  9 +++----
 tests/auto/qlabel/qlabel.pro     | 21 +++++----------
 tests/auto/qlabel/tst_qlabel.cpp | 58 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 78 insertions(+), 24 deletions(-)

diff --git a/src/gui/text/qfontengine_mac.mm b/src/gui/text/qfontengine_mac.mm
index d11083f..8ce437d 100644
--- a/src/gui/text/qfontengine_mac.mm
+++ b/src/gui/text/qfontengine_mac.mm
@@ -830,7 +830,6 @@ static OSStatus atsuPostLayoutCallback(ATSULayoutOperationSelector selector, ATS
             surrogates += (str[i].unicode() >= 0xd800 && str[i].unicode() < 0xdc00
                            && str[i+1].unicode() >= 0xdc00 && str[i+1].unicode() < 0xe000);
         }
-        Q_ASSERT(*nfo->numGlyphs == item->length - surrogates);
 #endif
         for (nextCharStop = item->from; nextCharStop < item->from + item->length; ++nextCharStop)
             if (item->charAttributes[nextCharStop].charStop)
@@ -856,10 +855,13 @@ static OSStatus atsuPostLayoutCallback(ATSULayoutOperationSelector selector, ATS
         QFixed xAdvance = FixedToQFixed(layoutData[glyphIdx + 1].realPos - layoutData[glyphIdx].realPos);
 
         if (glyphId != 0xffff || i == 0) {
-            nfo->glyphs->glyphs[i] = (glyphId & 0x00ffffff) | (fontIdx << 24);
+            if (i < nfo->glyphs->numGlyphs)
+            {
+                nfo->glyphs->glyphs[i] = (glyphId & 0x00ffffff) | (fontIdx << 24);
 
-            nfo->glyphs->advances_y[i] = yAdvance;
-            nfo->glyphs->advances_x[i] = xAdvance;
+                nfo->glyphs->advances_y[i] = yAdvance;
+                nfo->glyphs->advances_x[i] = xAdvance;
+            }
         } else {
             // ATSUI gives us 0xffff as glyph id at the index in the glyph array for
             // a character position that maps to a ligtature. Such a glyph id does not
@@ -1029,6 +1031,8 @@ bool QFontEngineMacMulti::stringToCMapInternal(const QChar *str, int len, QGlyph
     nfo.flags = flags;
     nfo.shaperItem = shaperItem;
 
+    int prevNumGlyphs = *nglyphs;
+
     QVarLengthArray<int> mappedFonts(len);
     for (int i = 0; i < len; ++i)
         mappedFonts[i] = 0;
@@ -1140,6 +1144,8 @@ bool QFontEngineMacMulti::stringToCMapInternal(const QChar *str, int len, QGlyph
     }
 
     ATSUClearLayoutCache(textLayout, kATSUFromTextBeginning);
+    if (prevNumGlyphs < *nfo.numGlyphs)
+        return false;
     return true;
 }
 
diff --git a/src/gui/text/qtextengine_mac.cpp b/src/gui/text/qtextengine_mac.cpp
index 4f20094..e101830 100644
--- a/src/gui/text/qtextengine_mac.cpp
+++ b/src/gui/text/qtextengine_mac.cpp
@@ -50,7 +50,6 @@ static void heuristicSetGlyphAttributes(const QChar *uc, int length, QGlyphLayou
 {
     // ### zeroWidth and justification are missing here!!!!!
 
-    Q_ASSERT(num_glyphs <= length);
     Q_UNUSED(num_glyphs);
 
 //     qDebug("QScriptEngine::heuristicSetGlyphAttributes, num_glyphs=%d", item->num_glyphs);
@@ -596,7 +595,7 @@ void QTextEngine::shapeTextMac(int item) const
     }
 
     while (true) {
-	ensureSpace(num_glyphs);
+        ensureSpace(num_glyphs);
         num_glyphs = layoutData->glyphLayout.numGlyphs - layoutData->used;
 
         QGlyphLayout g = availableGlyphs(&si);
@@ -611,9 +610,9 @@ void QTextEngine::shapeTextMac(int item) const
                              log_clusters,
                              attributes())) {
 
-		heuristicSetGlyphAttributes(str, len, &g, log_clusters, num_glyphs);
-		break;
-	}
+            heuristicSetGlyphAttributes(str, len, &g, log_clusters, num_glyphs);
+            break;
+        }
     }
 
     si.num_glyphs = num_glyphs;
diff --git a/tests/auto/qlabel/qlabel.pro b/tests/auto/qlabel/qlabel.pro
index 6d55c13..297f868 100644
--- a/tests/auto/qlabel/qlabel.pro
+++ b/tests/auto/qlabel/qlabel.pro
@@ -1,19 +1,10 @@
 load(qttest_p4)
-SOURCES  += tst_qlabel.cpp
-
-wince*:{
-    DEFINES += SRCDIR=\\\"\\\"
-} else:!symbian {
-    DEFINES += SRCDIR=\\\"$$PWD/\\\"
-}
-
-wince*|symbian {
-    addFiles.sources = *.png testdata
+SOURCES += tst_qlabel.cpp
+wince*::DEFINES += SRCDIR=\\\"\\\"
+else:!symbian:DEFINES += SRCDIR=\\\"$$PWD/\\\"
+wince*|symbian { 
+    addFiles.sources = *.png \
+        testdata
     addFiles.path = .
     DEPLOYMENT += addFiles
 }
-
-
-
-
-
diff --git a/tests/auto/qlabel/tst_qlabel.cpp b/tests/auto/qlabel/tst_qlabel.cpp
index dd03ef3..9eae9c9 100644
--- a/tests/auto/qlabel/tst_qlabel.cpp
+++ b/tests/auto/qlabel/tst_qlabel.cpp
@@ -50,6 +50,7 @@
 #include <qlineedit.h>
 #include <qmovie.h>
 #include <qpicture.h>
+#include <qmessagebox.h>
 
 //TESTED_CLASS=
 //TESTED_FILES=
@@ -112,6 +113,9 @@ private slots:
     void task226479_movieResize();
     void emptyPixmap();
 
+    void unicodeText_data();
+    void unicodeText();
+
 private:
     QLabel *testWidget;
     QPointer<Widget> test_box;
@@ -451,5 +455,59 @@ void tst_QLabel::emptyPixmap()
     QCOMPARE(label1.sizeHint(), label4.sizeHint());
 }
 
+/**
+    Test for QTBUG-4848 - unicode data corrupting QLabel display
+*/
+void tst_QLabel::unicodeText_data()
+{
+    QTest::addColumn<QString>("text");
+    QTest::addColumn<QString>("languageName");
+
+    /*
+    The "glass" phrase in Thai was the initial report for bug QTBUG-4848, was
+    originally found on http://www.columbia.edu/kermit/utf8.html.
+
+    The phrase is from an internet tradition regarding a striking phrase
+    that is translated into many different languages.  The utf8 strings
+    below were generated by using http://translate.google.com.
+
+    The glass phrase in Thai contains the ้ว character which manifests bug
+    QTBUG-4848
+
+    The last long phrase is an excerpt from Churchills "on the beaches"
+    speech, also translated using http://translate.google.com.
+    */
+
+    QTest::newRow("english") << QString::fromUtf8("I can eat glass and it doesn't hurt me.") << QString("english");
+    QTest::newRow("thai") << QString::fromUtf8("ฉันจะกินแก้วและไม่เจ็บฉัน") << QString("thai");
+    QTest::newRow("chinese") << QString::fromUtf8("我可以吃玻璃，并没有伤害我。") << QString("chinese");
+    QTest::newRow("arabic") << QString::fromUtf8("أستطيع أكل الزجاج ، وأنه لا يؤذيني.") << QString("arabic");
+    QTest::newRow("russian") << QString::fromUtf8("Я могу есть стекло, и не больно.") << QString("russian");
+    QTest::newRow("korean") << QString::fromUtf8("유리를 먹을 수있는, 그리고 그게 날 다치게하지 않습니다.") << QString("korean");
+    QTest::newRow("greek") << QString::fromUtf8("Μπορώ να φάτε γυαλί και δεν μου κάνει κακό.") << QString("greek");
+    QTest::newRow("german") << QString::fromUtf8("Ich kann Glas essen und es macht mich nicht heiß.") << QString("german");
+
+    QTest::newRow("thai_long") << QString::fromUtf8("เราจะต่อสู้ในทะเลและมหาสมุทร. เราจะต่อสู้ด้วยความมั่นใจเติบโตและความเจริญเติบโตในอากาศเราจะปกป้องเกาะของเราค่าใช้จ่ายใดๆอาจ."
+                                                    "เราจะต่อสู้บนชายหาดเราจะต่อสู้ในบริเวณเชื่อมโยงไปถึงเราจะต่อสู้ในช่องและในถนนที่เราจะต่อสู้ในภูเขานั้นเราจะไม่ยอม.")
+            << QString("thai_long");
+}
+
+void tst_QLabel::unicodeText()
+{
+    const QString testDataPath("testdata/unicodeText");
+    QFETCH(QString, text);
+    QFETCH(QString, languageName);
+    QFrame frame;
+    QVBoxLayout *layout = new QVBoxLayout();
+    QLabel *label = new QLabel(text, &frame);
+    layout->addWidget(label);
+    layout->setMargin(8);
+    frame.setLayout(layout);
+    frame.show();
+    QTest::qWaitForWindowShown(&frame);
+    QVERIFY(frame.isVisible());  // was successfully sized and shown
+    testWidget->show();
+}
+
 QTEST_MAIN(tst_QLabel)
 #include "tst_qlabel.moc"
-- 
cgit v0.12


From 31fefc7cc9dc01be244b362ada1c1b2f8aad7c47 Mon Sep 17 00:00:00 2001
From: Julian de Bhal <julian.debhal@nokia.com>
Date: Tue, 20 Oct 2009 12:32:19 +1000
Subject: Fix dangling shader manager pointers The QGLEngineShaderManager
 pointers in QGLCustomShaderStagePrivate have been changed to QPointers to
 prevent the QGLPixmapFilters in QGL2PaintEngineEx from dereferencing the
 QGLEngineShaderManager after it is destroyed.

Reviewed-by: Rhys Weatherley
---
 src/opengl/gl2paintengineex/qglcustomshaderstage.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/opengl/gl2paintengineex/qglcustomshaderstage.cpp b/src/opengl/gl2paintengineex/qglcustomshaderstage.cpp
index 24606bc..ab2026c 100644
--- a/src/opengl/gl2paintengineex/qglcustomshaderstage.cpp
+++ b/src/opengl/gl2paintengineex/qglcustomshaderstage.cpp
@@ -52,7 +52,7 @@ public:
     QGLCustomShaderStagePrivate() :
         m_manager(0) {}
 
-    QGLEngineShaderManager* m_manager;
+    QPointer<QGLEngineShaderManager> m_manager;
     QByteArray              m_source;
 };
 
-- 
cgit v0.12


From f38eb1b6edf8f6d758899c8ca4a4bae2d7eb4b92 Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Tue, 20 Oct 2009 13:51:06 +1000
Subject: Fix now invalid ExpectFail.

The bug causing this fail is now fixed, so remove the expectfails.
---
 tests/auto/qsqlquery/tst_qsqlquery.cpp | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/tests/auto/qsqlquery/tst_qsqlquery.cpp b/tests/auto/qsqlquery/tst_qsqlquery.cpp
index 546c105..98030d1 100644
--- a/tests/auto/qsqlquery/tst_qsqlquery.cpp
+++ b/tests/auto/qsqlquery/tst_qsqlquery.cpp
@@ -194,7 +194,6 @@ private slots:
     void sqlServerReturn0_data() { generic_data(); }
     void sqlServerReturn0();
 
-
 private:
     // returns all database connections
     void generic_data(const QString &engine=QString());
@@ -510,9 +509,7 @@ void tst_QSqlQuery::mysqlOutValues()
     QVERIFY_SQL( q, exec( "create procedure " + qTableName( "qtestproc" ) + " () "
                             "BEGIN select * from " + qTableName( "qtest" ) + " order by id; END" ) );
     QVERIFY_SQL( q, exec( "call " + qTableName( "qtestproc" ) + "()" ) );
-    QEXPECT_FAIL("", "There's a mysql bug that means only selects think they return data when running in prepared mode", Continue);
     QVERIFY_SQL( q, next() );
-    QEXPECT_FAIL("", "There's a mysql bug that means only selects think they return data when running in prepared mode", Continue);
     QCOMPARE( q.value( 1 ).toString(), QString( "VarChar1" ) );
 
     QVERIFY_SQL( q, exec( "drop procedure " + qTableName( "qtestproc" ) ) );
-- 
cgit v0.12


From 04648b44f0784223122a782320d0b09b5c1e9497 Mon Sep 17 00:00:00 2001
From: Rhys Weatherley <rhys.weatherley@nokia.com>
Date: Tue, 20 Oct 2009 16:46:46 +1000
Subject: Remove unnecessary PowerVR helper functions

The cross-process memory sharing code never really worked in the
way we needed it to - so remove it until something better comes along.

Reviewed-by: trustme
---
 .../gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c   | 60 ----------------------
 .../gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.h   | 15 ------
 2 files changed, 75 deletions(-)

diff --git a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
index c1b655a..17345a9 100644
--- a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
+++ b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
@@ -828,63 +828,3 @@ void pvrQwsSetSwapFunction
     drawable->swapFunction = func;
     drawable->userData = userData;
 }
-
-unsigned long pvrQwsGetMemoryId(PvrQwsDrawable *drawable)
-{
-    unsigned long addr;
-    unsigned long start;
-    unsigned long end;
-    unsigned long off;
-    unsigned long offset;
-    FILE *file;
-    char buffer[BUFSIZ];
-    char flags[16];
-
-    if (!drawable->backBuffersValid)
-        return 0;
-    addr = (unsigned long)
-        (drawable->backBuffers[drawable->currentBackBuffer]->pBase);
-
-    /* Search /proc/self/maps for the memory region that contains "addr".
-       The file offset for that memory region is the identifier we need */
-    file = fopen("/proc/self/maps", "r");
-    if (!file) {
-        perror("/proc/self/maps");
-        return 0;
-    }
-    offset = 0;
-    while (fgets(buffer, sizeof(buffer), file)) {
-        if (sscanf(buffer, "%lx-%lx %s %lx",
-                   &start, &end, flags, &off) < 4)
-            continue;
-        if (start <= addr && addr < end) {
-            offset = off;
-            break;
-        }
-    }
-    fclose(file);
-    return offset;
-}
-
-void *pvrQwsMapMemory(unsigned long id, int size)
-{
-    void *addr;
-    int fd = open("/dev/pvrsrv", O_RDWR, 0);
-    if (fd < 0) {
-        perror("/dev/pvrsrv");
-        return 0;
-    }
-    addr = mmap(0, (size_t)size, PROT_READ | PROT_WRITE,
-                MAP_SHARED, fd, (off_t)id);
-    if (addr == (void *)(-1)) {
-        perror("mmap pvr memory region");
-        addr = 0;
-    }
-    close(fd);
-    return addr;
-}
-
-void pvrQwsUnmapMemory(void *addr, int size)
-{
-    munmap(addr, size);
-}
diff --git a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.h b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.h
index b9e035f..55e0310 100644
--- a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.h
+++ b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.h
@@ -162,21 +162,6 @@ int pvrQwsSwapBuffers(PvrQwsDrawable *drawable, int repaintOnly);
 void pvrQwsSetSwapFunction
     (PvrQwsDrawable *drawable, PvrQwsSwapFunction func, void *userData);
 
-/* Get a memory identifier for the indicated drawable's buffer.
-   The identifier can be passed to another process and then
-   passed to pvrQwsMapMemory() to map the drawable's buffer into
-   the other process's address space.  Returns zero if the
-   memory identifier could not be determined.  This should only
-   be used for pixmap drawables */
-unsigned long pvrQwsGetMemoryId(PvrQwsDrawable *drawable);
-
-/* Map the memory buffer of a foreign application's drawable, as
-   indicated by "id" and "size".  Returns null if the map failed */
-void *pvrQwsMapMemory(unsigned long id, int size);
-
-/* Unmap the memory obtained from pvrQwsMapMemory() */
-void pvrQwsUnmapMemory(void *addr, int size);
-
 #ifdef __cplusplus
 };
 #endif
-- 
cgit v0.12


From 5b82db6e59aee775a5acc477d6e9dac9c453876d Mon Sep 17 00:00:00 2001
From: Richard Moe Gustavsen <richard.gustavsen@nokia.com>
Date: Sun, 18 Oct 2009 18:02:00 +0200
Subject: Cocoa: modal window reappears on screen after reactivating app

If you close a modal window, then activate different app, then
activate app again, the window will pop non-modal in front.
This patch makes sure that when we hide a window, we point
to the next window to receive keyboard focus.

Rev-By: MortenS
---
 src/gui/kernel/qwidget_mac.mm | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/gui/kernel/qwidget_mac.mm b/src/gui/kernel/qwidget_mac.mm
index c966aa3..05c6a5b 100644
--- a/src/gui/kernel/qwidget_mac.mm
+++ b/src/gui/kernel/qwidget_mac.mm
@@ -305,6 +305,8 @@ bool qt_mac_insideKeyWindow(const QWidget *w)
 {
 #ifdef QT_MAC_USE_COCOA
     return [[reinterpret_cast<NSView *>(w->winId()) window] isKeyWindow];
+#else
+    Q_UNUSED(w);
 #endif
     return false;
 }
@@ -3301,7 +3303,11 @@ void QWidgetPrivate::show_sys()
             [window miniaturize:window];
 #endif
         } else if (!q->testAttribute(Qt::WA_ShowWithoutActivating)) {
+#ifndef QT_MAC_USE_COCOA
             qt_event_request_activate(q);
+#else
+            [qt_mac_window_for(q) makeKeyWindow];
+#endif
         }
     } else if(topData()->embedded || !q->parentWidget() || q->parentWidget()->isVisible()) {
 #ifndef QT_MAC_USE_COCOA
@@ -3404,8 +3410,13 @@ void QWidgetPrivate::hide_sys()
                 }
 #endif
             }
-            if(w && w->isVisible() && !w->isMinimized())
-                qt_event_request_activate(w);
+            if(w && w->isVisible() && !w->isMinimized()) {
+#ifndef QT_MAC_USE_COCOA
+            qt_event_request_activate(w);
+#else
+            [qt_mac_window_for(w) makeKeyWindow];
+#endif
+            }
         }
     } else {
          invalidateBuffer(q->rect());
-- 
cgit v0.12


From 4ae09215de36fcfd17dc6875aca102d784d65012 Mon Sep 17 00:00:00 2001
From: Rhys Weatherley <rhys.weatherley@nokia.com>
Date: Tue, 20 Oct 2009 16:55:06 +1000
Subject: The shipped pvr2d.h/wsegl.h for PowerVR do not work with MBX

Reviewed-by: trustme
---
 src/plugins/gfxdrivers/powervr/README | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/plugins/gfxdrivers/powervr/README b/src/plugins/gfxdrivers/powervr/README
index 322a6b2..513e7f5 100644
--- a/src/plugins/gfxdrivers/powervr/README
+++ b/src/plugins/gfxdrivers/powervr/README
@@ -31,9 +31,10 @@ strictly Unix-style markers.
 * IMPORTANT: To build the QScreen plugin and the WSEGL library it depends *
 * on, the pvr2d.h, wsegl.h headers for your platform are required.  You   *
 * can find a copy of these headers in src/3rdparty/powervr for SGX based  *
-* platforms like the TI OMAP3xxx. They may also work on MBX platforms too *
-* depending on how old your libEGL is. You can tell Qt where to find      *
-* these headers by setting QMAKE_INCDIR_POWERVR in the mkspec.            *
+* platforms like the TI OMAP3xxx.  They probably will not work on MBX     *
+* because of differences in the layout of certain PVR2D structures.       *
+* You can tell Qt where to find the actual headers for your system by     *
+* setting QMAKE_INCDIR_POWERVR in the mkspec.                             *
 ***************************************************************************
 
 When you start a Qt/Embedded application, you should modify the QWS_DISPLAY
-- 
cgit v0.12


From 9d91a56ad5e39ddb237e10819a371e78defdf359 Mon Sep 17 00:00:00 2001
From: Markus Goetz <Markus.Goetz@nokia.com>
Date: Mon, 19 Oct 2009 16:23:47 +0200
Subject: Backport benchmarks/qnetworkreply to 4.5

Reviewed-by: TrustMe
---
 tests/benchmarks/benchmarks.pro                    |  1 +
 tests/benchmarks/qnetworkreply/qnetworkreply.pro   | 13 ++++
 .../benchmarks/qnetworkreply/tst_qnetworkreply.cpp | 74 ++++++++++++++++++++++
 3 files changed, 88 insertions(+)
 create mode 100644 tests/benchmarks/qnetworkreply/qnetworkreply.pro
 create mode 100644 tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp

diff --git a/tests/benchmarks/benchmarks.pro b/tests/benchmarks/benchmarks.pro
index 8e2c243..fb2b9ea 100644
--- a/tests/benchmarks/benchmarks.pro
+++ b/tests/benchmarks/benchmarks.pro
@@ -8,6 +8,7 @@ SUBDIRS = containers-associative \
 	qpixmap \
 	blendbench \
 	qstringlist \
+        qnetworkreply \
 	qobject \
         qrect \
 	qregexp	\
diff --git a/tests/benchmarks/qnetworkreply/qnetworkreply.pro b/tests/benchmarks/qnetworkreply/qnetworkreply.pro
new file mode 100644
index 0000000..1e67d81
--- /dev/null
+++ b/tests/benchmarks/qnetworkreply/qnetworkreply.pro
@@ -0,0 +1,13 @@
+load(qttest_p4)
+TEMPLATE = app
+TARGET = tst_qnetworkreply
+DEPENDPATH += .
+INCLUDEPATH += .
+
+QT -= gui
+QT += network
+
+CONFIG += release
+
+# Input
+SOURCES += tst_qnetworkreply.cpp
diff --git a/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
new file mode 100644
index 0000000..666e4f1
--- /dev/null
+++ b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
@@ -0,0 +1,74 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+// This file contains benchmarks for QNetworkReply functions.
+
+#include <QDebug>
+#include <qtest.h>
+#include <QtTest/QtTest>
+#include <QtNetwork/qnetworkreply.h>
+#include <QtNetwork/qnetworkrequest.h>
+#include <QtNetwork/qnetworkaccessmanager.h>
+#include "../../auto/network-settings.h"
+
+class tst_qnetworkreply : public QObject
+{
+    Q_OBJECT
+private slots:
+    void httpLatency();
+
+};
+
+void tst_qnetworkreply::httpLatency()
+{
+    QNetworkAccessManager manager;
+    QBENCHMARK{
+        QNetworkRequest request(QUrl("http://" + QtNetworkSettings::serverName() + "/qtest/"));
+        QNetworkReply* reply = manager.get(request);
+        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(5);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        delete reply;
+    }
+}
+
+QTEST_MAIN(tst_qnetworkreply)
+
+#include "main.moc"
-- 
cgit v0.12


From 5fd8c58dde0c61a723ab124ac74c863f67288a14 Mon Sep 17 00:00:00 2001
From: Markus Goetz <Markus.Goetz@nokia.com>
Date: Mon, 19 Oct 2009 17:16:20 +0200
Subject: Add a up/down benchmark to benchmarks/qnetworkreply

Reviewed-by: Peter Hartmann
---
 .../benchmarks/qnetworkreply/tst_qnetworkreply.cpp | 39 +++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
index 666e4f1..e622d62 100644
--- a/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
+++ b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
@@ -53,7 +53,10 @@ class tst_qnetworkreply : public QObject
     Q_OBJECT
 private slots:
     void httpLatency();
-
+#ifndef QT_NO_OPENSSL
+    void echoPerformance_data();
+    void echoPerformance();
+#endif
 };
 
 void tst_qnetworkreply::httpLatency()
@@ -69,6 +72,40 @@ void tst_qnetworkreply::httpLatency()
     }
 }
 
+#ifndef QT_NO_OPENSSL
+void tst_qnetworkreply::echoPerformance_data()
+{
+     QTest::addColumn<bool>("ssl");
+     QTest::newRow("no_ssl") << false;
+     QTest::newRow("ssl") << true;
+}
+
+void tst_qnetworkreply::echoPerformance()
+{
+    QFETCH(bool, ssl);
+    QNetworkAccessManager manager;
+    QNetworkRequest request(QUrl((ssl ? "https://" : "http://") + QtNetworkSettings::serverName() + "/qtest/cgi-bin/echo.cgi"));
+
+    QByteArray data;
+    data.resize(1024*1024*10); // 10 MB
+    // init with garbage. needed so ssl cannot compress it in an efficient way.
+    for (int i = 0; i < data.size() / sizeof(int); i++) {
+        int r = qrand();
+        data.data()[i*sizeof(int)] = r;
+    }
+
+    QBENCHMARK{
+        QNetworkReply* reply = manager.post(request, data);
+        connect(reply, SIGNAL(sslErrors( const QList<QSslError> &)), reply, SLOT(ignoreSslErrors()));
+        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(5);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        QVERIFY(reply->error() == QNetworkReply::NoError);
+        delete reply;
+    }
+}
+#endif
+
 QTEST_MAIN(tst_qnetworkreply)
 
 #include "main.moc"
-- 
cgit v0.12


From 3d4804a229e6cb869aa03481dd871e756ffa35ae Mon Sep 17 00:00:00 2001
From: Benjamin Poulain <benjamin.poulain@nokia.com>
Date: Tue, 20 Oct 2009 11:08:04 +0200
Subject: Revert "Change the way we handle KeyboardUIMode on Mac" This will be
 handled differently (QTBUG-4751)

This reverts commit b12fb5861ce09539c04cd51db12a9bfbe32a4774.
---
 src/corelib/global/qnamespace.qdoc |  4 +++-
 src/gui/kernel/qapplication.cpp    | 20 ++++----------------
 2 files changed, 7 insertions(+), 17 deletions(-)

diff --git a/src/corelib/global/qnamespace.qdoc b/src/corelib/global/qnamespace.qdoc
index ba05b00..e8d6df0 100644
--- a/src/corelib/global/qnamespace.qdoc
+++ b/src/corelib/global/qnamespace.qdoc
@@ -1827,7 +1827,9 @@
     \value TabFocus  the widget accepts focus by tabbing.
     \value ClickFocus  the widget accepts focus by clicking.
     \value StrongFocus  the widget accepts focus by both tabbing
-                    and clicking.
+                    and clicking. On Mac OS X this will also
+                    be indicate that the widget accepts tab focus
+                    when in 'Text/List focus mode'.
     \value WheelFocus  like Qt::StrongFocus plus the widget accepts
                     focus by using the mouse wheel.
     \value NoFocus  the widget does not accept focus.
diff --git a/src/gui/kernel/qapplication.cpp b/src/gui/kernel/qapplication.cpp
index 41d8098..f48c551 100644
--- a/src/gui/kernel/qapplication.cpp
+++ b/src/gui/kernel/qapplication.cpp
@@ -68,9 +68,6 @@
 #include "private/qstylesheetstyle_p.h"
 #include "private/qstyle_p.h"
 #include "qmessagebox.h"
-#include "qlineedit.h"
-#include "qlistview.h"
-#include "qtextedit.h"
 #include <QtGui/qgraphicsproxywidget.h>
 
 #include "qinputcontext.h"
@@ -2501,6 +2498,8 @@ void QApplication::setActiveWindow(QWidget* act)
 */
 QWidget *QApplicationPrivate::focusNextPrevChild_helper(QWidget *toplevel, bool next)
 {
+    uint focus_flag = qt_tab_all_widgets ? Qt::TabFocus : Qt::StrongFocus;
+
     QWidget *f = toplevel->focusWidget();
     if (!f)
         f = toplevel;
@@ -2508,22 +2507,11 @@ QWidget *QApplicationPrivate::focusNextPrevChild_helper(QWidget *toplevel, bool
     QWidget *w = f;
     QWidget *test = f->d_func()->focus_next;
     while (test && test != f) {
-        if ((test->focusPolicy() & Qt::TabFocus)
+        if ((test->focusPolicy() & focus_flag) == focus_flag
             && !(test->d_func()->extra && test->d_func()->extra->focus_proxy)
             && test->isVisibleTo(toplevel) && test->isEnabled()
             && !(w->windowType() == Qt::SubWindow && !w->isAncestorOf(test))
-            && (toplevel->windowType() != Qt::SubWindow || toplevel->isAncestorOf(test))
-            && (qt_tab_all_widgets
-#ifndef QT_NO_LINEEDIT
-                || qobject_cast<QLineEdit*>(test)
-#endif
-#ifndef QT_NO_TEXTEDIT
-                || qobject_cast<QTextEdit*>(test)
-#endif
-#ifndef QT_NO_ITEMVIEWS
-                || qobject_cast<QListView*>(test)
-#endif
-                )) {
+            && (toplevel->windowType() != Qt::SubWindow || toplevel->isAncestorOf(test))) {
             w = test;
             if (next)
                 break;
-- 
cgit v0.12


From 5651d2547261ccecbf50f8141c634f59c0adc00d Mon Sep 17 00:00:00 2001
From: Dean Dettman <dean.dettman@nokia.com>
Date: Tue, 20 Oct 2009 11:13:02 +0200
Subject: Adds Key_Back and Key_Forward menu glyphs on mac(carbon)

This change improves the behavior of QMenu when Key_Back and Key_Forward
are used as shortcuts. A dotted arrow appears on carbon, and
on Cocoa the image is blank, instead of undefined as it was before.

Task-number:     QTBUG-4873
Reviewed-by:     msorvig
---
 src/gui/widgets/qmenu_mac.mm | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/gui/widgets/qmenu_mac.mm b/src/gui/widgets/qmenu_mac.mm
index 354161d..a7f6f0d 100644
--- a/src/gui/widgets/qmenu_mac.mm
+++ b/src/gui/widgets/qmenu_mac.mm
@@ -572,6 +572,10 @@ static void qt_mac_get_accel(quint32 accel_key, quint32 *modif, quint32 *key) {
             *key = kMenuNorthwestArrowGlyph;
         else if (accel_key == Qt::Key_End)
             *key = kMenuSoutheastArrowGlyph;
+        else if (accel_key == Qt::Key_Back)
+            *key = kMenuLeftArrowDashedGlyph;
+        else if (accel_key == Qt::Key_Forward)
+            *key = kMenuRightArrowDashedGlyph;
     }
 }
 #else // Cocoa
@@ -1239,6 +1243,10 @@ NSString *keySequenceToKeyEqivalent(const QKeySequence &accel)
         keyEquiv[0] = NSHomeFunctionKey;
     else if (accel_key == Qt::Key_End)
         keyEquiv[0] = NSEndFunctionKey;
+    else if (accel_key == Qt::Key_Back)
+        keyEquiv[0] = kMenuLeftArrowDashedGlyph;  // ### Cocoa has no equivalent - no icon is displayed
+    else if (accel_key == Qt::Key_Forward)
+        keyEquiv[0] = kMenuRightArrowDashedGlyph;  // ### Cocoa has no equivalent - no icon is displayed
     else
         keyEquiv[0] = unichar(QChar(accel_key).toLower().unicode());
     return [NSString stringWithCharacters:keyEquiv length:1];
-- 
cgit v0.12


From b2c51304a238845da35f20953ace0f4a291ceabc Mon Sep 17 00:00:00 2001
From: Friedemann Kleint <Friedemann.Kleint@nokia.com>
Date: Tue, 20 Oct 2009 11:36:01 +0200
Subject: i18n: Complete German translations for 4.6.0 (XmlPatterns)

---
 translations/qt_de.ts | 643 +++++++++++++++++++++++++-------------------------
 1 file changed, 326 insertions(+), 317 deletions(-)

diff --git a/translations/qt_de.ts b/translations/qt_de.ts
index c09daa9..0d329e5 100644
--- a/translations/qt_de.ts
+++ b/translations/qt_de.ts
@@ -140,9 +140,22 @@ Bitte prüfen Sie die Gstreamer-Installation und stellen Sie sicher, dass das Pa
     </message>
 </context>
 <context>
+    <name>Phonon::MMF</name>
+    <message>
+        <location filename="../src/3rdparty/phonon/mmf/audiooutput.cpp" line="+110"/>
+        <source>Audio Output</source>
+        <translation>Audio-Ausgabe</translation>
+    </message>
+    <message>
+        <location line="+1"/>
+        <source>The audio output device</source>
+        <translation>Audio-Ausgabegerät</translation>
+    </message>
+</context>
+<context>
     <name>Phonon::MMF::AudioEqualizer</name>
     <message>
-        <location filename="../src/3rdparty/phonon/mmf/audioequalizer.cpp" line="+74"/>
+        <location filename="../src/3rdparty/phonon/mmf/audioequalizer.cpp" line="+75"/>
         <source>Frequency band, %1 Hz</source>
         <translation>Frequenzband, %1 Hz</translation>
     </message>
@@ -917,7 +930,7 @@ nach
         <translation>Diese Socket-Operation wird nicht unterstützt</translation>
     </message>
     <message>
-        <location line="+187"/>
+        <location line="+200"/>
         <source>Socket operation timed out</source>
         <translation>Das Zeitlimit für die Operation wurde überschritten</translation>
     </message>
@@ -953,7 +966,7 @@ nach
 <context>
     <name>QApplication</name>
     <message>
-        <location filename="../src/gui/kernel/qapplication.cpp" line="+2306"/>
+        <location filename="../src/gui/kernel/qapplication.cpp" line="+2290"/>
         <source>QT_LAYOUT_DIRECTION</source>
         <comment>Translate this string to the string &apos;LTR&apos; in left-to-right languages or to &apos;RTL&apos; in right-to-left languages (such as Hebrew and Arabic) to get proper widget layout.</comment>
         <translation>LTR</translation>
@@ -1023,7 +1036,7 @@ nach
 <context>
     <name>QColorDialog</name>
     <message>
-        <location filename="../src/gui/dialogs/qcolordialog.cpp" line="+1348"/>
+        <location filename="../src/gui/dialogs/qcolordialog.cpp" line="+1349"/>
         <source>Hu&amp;e:</source>
         <translation>Farb&amp;ton:</translation>
     </message>
@@ -1063,7 +1076,7 @@ nach
         <translation>Farbauswahl</translation>
     </message>
     <message>
-        <location line="+178"/>
+        <location line="+180"/>
         <source>&amp;Basic colors</source>
         <translation>Grundfar&amp;ben</translation>
     </message>
@@ -1263,7 +1276,7 @@ nach
     <message>
         <location filename="../src/gui/dialogs/qmessagebox.cpp" line="+1872"/>
         <location line="+464"/>
-        <location filename="../src/gui/widgets/qdialogbuttonbox.cpp" line="+619"/>
+        <location filename="../src/gui/widgets/qdialogbuttonbox.cpp" line="+606"/>
         <source>OK</source>
         <translation>OK</translation>
     </message>
@@ -1447,7 +1460,7 @@ nach
 <context>
     <name>QErrorMessage</name>
     <message>
-        <location filename="../src/gui/dialogs/qerrormessage.cpp" line="+413"/>
+        <location filename="../src/gui/dialogs/qerrormessage.cpp" line="+414"/>
         <source>&amp;Show this message again</source>
         <translation>Diese Meldung wieder an&amp;zeigen</translation>
     </message>
@@ -1457,7 +1470,7 @@ nach
         <translation>&amp;OK</translation>
     </message>
     <message>
-        <location line="-206"/>
+        <location line="-207"/>
         <source>Debug Message:</source>
         <translation>Debug-Ausgabe:</translation>
     </message>
@@ -1538,7 +1551,7 @@ nach
         <translation>Details</translation>
     </message>
     <message>
-        <location filename="../src/gui/itemviews/qfileiconprovider.cpp" line="+444"/>
+        <location filename="../src/gui/itemviews/qfileiconprovider.cpp" line="+464"/>
         <location line="+1"/>
         <source>File</source>
         <translation>Datei</translation>
@@ -1567,12 +1580,12 @@ nach
         <translation>S&amp;peichern</translation>
     </message>
     <message>
-        <location line="+1801"/>
+        <location line="+1807"/>
         <source>Recent Places</source>
         <translation>Zuletzt besucht</translation>
     </message>
     <message>
-        <location line="-2511"/>
+        <location line="-2517"/>
         <source>&amp;Rename</source>
         <translation>&amp;Umbenennen</translation>
     </message>
@@ -1836,50 +1849,50 @@ Möchten Sie die Datei trotzdem löschen?</translation>
     <name>QFontDatabase</name>
     <message>
         <location filename="../src/gui/text/qfontdatabase.cpp" line="+102"/>
-        <location line="+1330"/>
+        <location line="+1335"/>
         <source>Normal</source>
         <translation>Normal</translation>
     </message>
     <message>
-        <location line="-1327"/>
+        <location line="-1332"/>
         <location line="+12"/>
-        <location line="+1303"/>
+        <location line="+1308"/>
         <source>Bold</source>
         <translation>Fett</translation>
     </message>
     <message>
-        <location line="-1312"/>
-        <location line="+1314"/>
+        <location line="-1317"/>
+        <location line="+1319"/>
         <source>Demi Bold</source>
         <translation>Halbfett</translation>
     </message>
     <message>
-        <location line="-1311"/>
+        <location line="-1316"/>
         <location line="+18"/>
-        <location line="+1289"/>
+        <location line="+1294"/>
         <source>Black</source>
         <translation>Schwarz</translation>
     </message>
     <message>
-        <location line="-1299"/>
+        <location line="-1304"/>
         <source>Demi</source>
         <translation>Semi</translation>
     </message>
     <message>
         <location line="+6"/>
-        <location line="+1299"/>
+        <location line="+1304"/>
         <source>Light</source>
         <translation>Leicht</translation>
     </message>
     <message>
-        <location line="-1153"/>
-        <location line="+1156"/>
+        <location line="-1158"/>
+        <location line="+1161"/>
         <source>Italic</source>
         <translation>Kursiv</translation>
     </message>
     <message>
-        <location line="-1153"/>
-        <location line="+1155"/>
+        <location line="-1158"/>
+        <location line="+1160"/>
         <source>Oblique</source>
         <translation>Schräggestellt</translation>
     </message>
@@ -2255,13 +2268,9 @@ Möchten Sie die Datei trotzdem löschen?</translation>
 <context>
     <name>QHostInfoAgent</name>
     <message>
-        <location filename="../src/network/kernel/qhostinfo_unix.cpp" line="+178"/>
-        <location line="+9"/>
-        <location line="+80"/>
+        <location filename="../src/network/kernel/qhostinfo_unix.cpp" line="+257"/>
         <location line="+32"/>
-        <location filename="../src/network/kernel/qhostinfo_win.cpp" line="+165"/>
-        <location line="+9"/>
-        <location line="+56"/>
+        <location filename="../src/network/kernel/qhostinfo_win.cpp" line="+220"/>
         <location line="+27"/>
         <source>Host not found</source>
         <translation>Rechner konnte nicht gefunden werden</translation>
@@ -2282,7 +2291,7 @@ Möchten Sie die Datei trotzdem löschen?</translation>
         <translation>Unbekannter Fehler</translation>
     </message>
     <message>
-        <location filename="../src/network/kernel/qhostinfo_win.cpp" line="-71"/>
+        <location filename="../src/network/kernel/qhostinfo_win.cpp" line="-67"/>
         <source>No host name given</source>
         <translation>Es wurde kein Hostname angegeben</translation>
     </message>
@@ -2612,7 +2621,7 @@ Möchten Sie die Datei trotzdem löschen?</translation>
 <context>
     <name>QIODevice</name>
     <message>
-        <location filename="../src/corelib/global/qglobal.cpp" line="+2046"/>
+        <location filename="../src/corelib/global/qglobal.cpp" line="+2058"/>
         <source>Permission denied</source>
         <translation>Zugriff verweigert</translation>
     </message>
@@ -3092,7 +3101,7 @@ Möchten Sie die Datei trotzdem löschen?</translation>
 <context>
     <name>QMenuBar</name>
     <message>
-        <location filename="../src/gui/widgets/qmenu_symbian.cpp" line="+401"/>
+        <location filename="../src/gui/widgets/qmenu_symbian.cpp" line="+404"/>
         <source>Actions</source>
         <translation>Optionen</translation>
     </message>
@@ -3556,7 +3565,7 @@ Möchten Sie die Datei trotzdem löschen?</translation>
 <context>
     <name>QObject</name>
     <message>
-        <location filename="../src/network/kernel/qhostinfo_unix.cpp" line="-101"/>
+        <location filename="../src/network/kernel/qhostinfo_unix.cpp" line="-97"/>
         <source>Invalid hostname</source>
         <translation>Ungültiger Rechnername</translation>
     </message>
@@ -3782,7 +3791,7 @@ Möchten Sie die Datei trotzdem löschen?</translation>
         <translation>unbekannt</translation>
     </message>
     <message>
-        <location filename="../src/gui/dialogs/qprintdialog_win.cpp" line="+259"/>
+        <location filename="../src/gui/dialogs/qprintdialog_win.cpp" line="+266"/>
         <source>OK</source>
         <translation>OK</translation>
     </message>
@@ -4492,7 +4501,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <translation>Zeitüberschreitung</translation>
     </message>
     <message>
-        <location filename="../src/corelib/io/qprocess.cpp" line="+851"/>
+        <location filename="../src/corelib/io/qprocess.cpp" line="+855"/>
         <location line="+52"/>
         <location filename="../src/corelib/io/qprocess_win.cpp" line="-211"/>
         <location line="+50"/>
@@ -5834,7 +5843,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <translation>Abbrechen</translation>
     </message>
     <message>
-        <location line="+152"/>
+        <location line="+151"/>
         <source>Exit</source>
         <translation>Beenden</translation>
     </message>
@@ -6058,7 +6067,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
 <context>
     <name>QTextControl</name>
     <message>
-        <location filename="../src/gui/text/qtextcontrol.cpp" line="+2001"/>
+        <location filename="../src/gui/text/qtextcontrol.cpp" line="+2007"/>
         <source>&amp;Undo</source>
         <translation>&amp;Rückgängig</translation>
     </message>
@@ -6216,7 +6225,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
 <context>
     <name>QWebFrame</name>
     <message>
-        <location filename="../src/3rdparty/webkit/WebKit/qt/WebCoreSupport/FrameLoaderClientQt.cpp" line="+706"/>
+        <location filename="../src/3rdparty/webkit/WebKit/qt/WebCoreSupport/FrameLoaderClientQt.cpp" line="+704"/>
         <source>Request cancelled</source>
         <translation>Anfrage wurde abgebrochen</translation>
     </message>
@@ -6861,17 +6870,17 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         </translation>
     </message>
     <message>
-        <location filename="../src/3rdparty/webkit/WebKit/qt/Api/qwebpage.cpp" line="+1726"/>
+        <location filename="../src/3rdparty/webkit/WebKit/qt/Api/qwebpage.cpp" line="+1727"/>
         <source>JavaScript Alert - %1</source>
         <translation>JavaScript-Hinweis - %1</translation>
     </message>
     <message>
-        <location line="+15"/>
+        <location line="+16"/>
         <source>JavaScript Confirm - %1</source>
         <translation>JavaScript-Bestätigung - %1</translation>
     </message>
     <message>
-        <location line="+17"/>
+        <location line="+18"/>
         <source>JavaScript Prompt - %1</source>
         <translation>JavaScript-Eingabeaufforderung - %1</translation>
     </message>
@@ -6886,7 +6895,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <translation>Das Skript dieser Webseite ist fehlerhaft. Möchten Sie es anhalten?</translation>
     </message>
     <message>
-        <location line="+382"/>
+        <location line="+383"/>
         <source>Move the cursor to the next character</source>
         <translation>Positionsmarke auf folgendes Zeichen setzen</translation>
     </message>
@@ -7107,7 +7116,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
 <context>
     <name>QWidget</name>
     <message>
-        <location filename="../src/gui/kernel/qwidget.cpp" line="+5651"/>
+        <location filename="../src/gui/kernel/qwidget.cpp" line="+5666"/>
         <source>*</source>
         <translation>*</translation>
     </message>
@@ -8098,7 +8107,7 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
     <message>
         <location line="+10"/>
         <source>In an XSL-T pattern, only function %1 and %2, not %3, can be used for matching.</source>
-        <translation>Bei einem XSL-T-Suchmuster dürfen nur die Funktionen %1 und %2, nicht jedoch  %3 zur Suche verwendet werden.</translation>
+        <translation>Bei einem XSL-T-Suchmuster dürfen nur die Funktionen %1 und %2, nicht jedoch %3 zur Suche verwendet werden.</translation>
     </message>
     <message>
         <location line="+63"/>
@@ -8138,17 +8147,17 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
     <message>
         <location line="-152"/>
         <source>W3C XML Schema identity constraint selector</source>
-        <translation type="unfinished"></translation>
+        <translation>W3C XML Schema identity constraint selector</translation>
     </message>
     <message>
         <location line="+3"/>
         <source>W3C XML Schema identity constraint field</source>
-        <translation type="unfinished"></translation>
+        <translation>W3C XML Schema identity constraint field</translation>
     </message>
     <message>
         <location line="+4"/>
         <source>A construct was encountered which is disallowed in the current language(%1).</source>
-        <translation type="unfinished"></translation>
+        <translation>Es wurde ein Sprachkonstrukt angetroffen, was in der aktuellen Sprache (%1) nicht erlaubt ist.</translation>
     </message>
     <message>
         <location line="+3804"/>
@@ -8491,206 +8500,206 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdschemachecker.cpp" line="+227"/>
         <source>%1 has inheritance loop in its base type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 hat eine zirkuläre Vererbung im Basistyp %2.</translation>
     </message>
     <message>
         <location line="+5"/>
         <location line="+24"/>
         <source>Circular inheritance of base type %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Zirkuläre Vererbung im Basistyp %1.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Circular inheritance of union %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Zirkuläre Vererbung bei der Vereinigung %1.</translation>
     </message>
     <message>
         <location line="+25"/>
         <source>%1 is not allowed to derive from %2 by restriction as the latter defines it as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf nicht durch Einschränkung von %2 abgeleitet werden, da letzterer sie als final deklariert.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>%1 is not allowed to derive from %2 by extension as the latter defines it as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf nicht durch Erweiterung von %2 abgeleitet werden, da letzterer sie als final deklariert.</translation>
     </message>
     <message>
         <location line="+31"/>
         <source>Base type of simple type %1 cannot be complex type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %2 kann nicht Basisklasse des einfachen Typs %1 sein.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Simple type %1 cannot have direct base type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ %1 kann nicht den unmittelbaren Basistyp %2 haben.</translation>
     </message>
     <message>
         <location line="+33"/>
         <location line="+9"/>
         <source>Simple type %1 is not allowed to have base type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ %1 darf nicht den Basistyp %2 haben.</translation>
     </message>
     <message>
         <location line="+12"/>
         <source>Simple type %1 can only have simple atomic type as base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ %1 kann nur einen einfachen. atomaren Basistyp haben.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Simple type %1 cannot derive from %2 as the latter defines restriction as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf nicht von %2 abgeleitet werden, da letzterer die Einschränkung als final deklariert.</translation>
     </message>
     <message>
         <location line="+13"/>
         <location line="+484"/>
         <source>Variety of item type of %1 must be either atomic or union.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Varietät der Typen von %1 muss entweder atomar oder eine Vereinigung sein.</translation>
     </message>
     <message>
         <location line="-474"/>
         <location line="+483"/>
         <source>Variety of member types of %1 must be atomic.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Varietät der Typen von %1 muss atomar sein.</translation>
     </message>
     <message>
         <location line="-470"/>
         <location line="+451"/>
         <source>%1 is not allowed to derive from %2 by list as the latter defines it as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf nicht durch Listen von %2 abgeleitet werden, da sie letzterer sie als final deklariert.</translation>
     </message>
     <message>
         <location line="-431"/>
         <source>Simple type %1 is only allowed to have %2 facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ %1 darf nur die Facette %2 haben.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>Base type of simple type %1 must have variety of type list.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp des einfachen Typs %1 muss eine Varietät des Typs Liste haben.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Base type of simple type %1 has defined derivation by restriction as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp des einfachen Typs %1 definiert Vererbung durch Einschränkung als final.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Item type of base type does not match item type of %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Elementtyp des Basistyps entspricht nicht dem Elementtyp von %1.</translation>
     </message>
     <message>
         <location line="+26"/>
         <location line="+93"/>
         <source>Simple type %1 contains not allowed facet type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ %1 enthält einen nicht erlaubten Facettentyp %2.</translation>
     </message>
     <message>
         <location line="-72"/>
         <location line="+413"/>
         <source>%1 is not allowed to derive from %2 by union as the latter defines it as final.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf nicht durch Vereinigung von %2 abgeleitet werden, da sie letzterer sie als final deklariert.</translation>
     </message>
     <message>
         <location line="-404"/>
         <source>%1 is not allowed to have any facets.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf keine Facetten haben.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Base type %1 of simple type %2 must have variety of union.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp %1 des einfachen Typs %2 muss eine Varietät des Typs Vereinigung haben.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Base type %1 of simple type %2 is not allowed to have restriction in %3 attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp %1 des einfachen Typs %2 darf keine Einschränkung im %3 Attribut haben.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Member type %1 cannot be derived from member type %2 of %3&apos;s base type %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ %1 des Mitglieds darf nicht vom Typ %2 des Mitglieds vom Basistyp %4 von %3 sein.</translation>
     </message>
     <message>
         <location line="+65"/>
         <source>Derivation method of %1 must be extension because the base type %2 is a simple type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Erweiterung muss als Vererbungsmethode für %1 verwendet werden, da der Basistyp %2 ein einfacher Typ ist.</translation>
     </message>
     <message>
         <location line="+30"/>
         <source>Complex type %1 has duplicated element %2 in its content model.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 hat ein dupliziertes Element %2 in seinem Inhaltsmodell.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Complex type %1 has non-deterministic content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 hat nicht-deterministischen Inhalt.</translation>
     </message>
     <message>
         <location line="+21"/>
         <source>Attributes of complex type %1 are not a valid extension of the attributes of base type %2: %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attribute des komplexen Typs %1 sind keine gültige Erweiterung der Attribute des Basistyps %2: %3.</translation>
     </message>
     <message>
         <location line="+37"/>
         <source>Content model of complex type %1 is not a valid extension of content model of %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Inhaltsmodell des komplexen Typs %1 ist keine gültige Erweiterung des Inhaltsmodells von %2.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>Complex type %1 must have simple content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 kann nur einfachen Inhalt haben.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Complex type %1 must have the same simple type as its base class %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 kann nur einen einfachen Typ als Basisklasse %2 haben.</translation>
     </message>
     <message>
         <location line="+67"/>
         <source>Complex type %1 cannot be derived from base type %2%3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 kann nicht vom Basistyp %2 abgeleitet werden%3.</translation>
     </message>
     <message>
         <location line="+14"/>
         <source>Attributes of complex type %1 are not a valid restriction from the attributes of base type %2: %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attribute des komplexen Typs %1 sind keine gültige Einschränkung der Attribute des Basistyps %2: %3.</translation>
     </message>
     <message>
         <location line="+14"/>
         <source>Complex type %1 with simple content cannot be derived from complex base type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 einfachen Inhalts darf nicht vom komplexen Basistyp %2 abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+35"/>
         <source>Item type of simple type %1 cannot be a complex type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Elementtyp des einfachen Typs %1 kann kein komplexer Typ sein.</translation>
     </message>
     <message>
         <location line="+44"/>
         <source>Member type of simple type %1 cannot be a complex type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ eines Mitglieds des einfachen Typs %1 kann kein komplexer Typ sein.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>%1 is not allowed to have a member type with the same name as itself.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 darf keinen Typ eines Mitglieds desselben Namens haben.</translation>
     </message>
     <message>
         <location line="+83"/>
         <location line="+29"/>
         <location line="+34"/>
         <source>%1 facet collides with %2 facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 steht im Widerspruch zu der Facette %2.</translation>
     </message>
     <message>
         <location line="-20"/>
         <source>%1 facet must have the same value as %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss denselben Wert wie die Facette %2 des Basistyps haben.</translation>
     </message>
     <message>
         <location line="+37"/>
         <source>%1 facet must be equal or greater than %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss größer oder gleich der Facette %2 des Basistyps sein.</translation>
     </message>
     <message>
         <location line="+19"/>
@@ -8702,333 +8711,333 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <location line="+34"/>
         <location line="+35"/>
         <source>%1 facet must be less than or equal to %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss kleiner oder gleich der Facette %2 des Basistyps sein.</translation>
     </message>
     <message>
         <location line="-389"/>
         <source>%1 facet contains invalid regular expression</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 enthält einen ungültigen regulären Ausdruck</translation>
     </message>
     <message>
         <location line="+15"/>
         <source>Unknown notation %1 used in %2 facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %2 enthält eine ungültige Notation %1.</translation>
     </message>
     <message>
         <location line="+20"/>
         <source>%1 facet contains invalid value %2: %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 enthält einen ungültigen Wert %2: %3.</translation>
     </message>
     <message>
         <location line="+22"/>
         <source>%1 facet cannot be %2 or %3 if %4 facet of base type is %5.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 kann nicht %2 oder %3 sein, wenn die Facette %4 des Basistyps %5 ist.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>%1 facet cannot be %2 if %3 facet of base type is %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 kann nicht %2 sein, wenn die Facette %3 des Basistyps %4 ist.</translation>
     </message>
     <message>
         <location line="+20"/>
         <location line="+55"/>
         <location line="+230"/>
         <source>%1 facet must be less than or equal to %2 facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss kleiner oder gleich der Facette %2 sein.</translation>
     </message>
     <message>
         <location line="-257"/>
         <location line="+134"/>
         <location line="+82"/>
         <source>%1 facet must be less than %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss kleiner der Facette %2 des Basistyps sein.</translation>
     </message>
     <message>
         <location line="-201"/>
         <location line="+79"/>
         <source>%1 facet and %2 facet cannot appear together.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facetten %1 und %2 können nicht zusammen erscheinen.</translation>
     </message>
     <message>
         <location line="-27"/>
         <location line="+12"/>
         <location line="+113"/>
         <source>%1 facet must be greater than %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss größer als die Facette %2 des Basistyps sein.</translation>
     </message>
     <message>
         <location line="-86"/>
         <location line="+58"/>
         <source>%1 facet must be less than %2 facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss kleiner als die Facette %2 sein.</translation>
     </message>
     <message>
         <location line="-42"/>
         <location line="+58"/>
         <source>%1 facet must be greater than or equal to %2 facet of base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facette %1 muss größer oder gleich der Facette %2 des Basistyps sein.</translation>
     </message>
     <message>
         <location line="+113"/>
         <source>Simple type contains not allowed facet %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ enthält eine unzulässige Facette %1.</translation>
     </message>
     <message>
         <location line="+12"/>
         <source>%1, %2, %3, %4, %5 and %6 facets are not allowed when derived by list.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Facetten %1, %2, %3, %4, %5 und %6 sind bei Vererbung durch Listen nicht zulässig.</translation>
     </message>
     <message>
         <location line="+16"/>
         <source>Only %1 and %2 facets are allowed when derived by union.</source>
-        <translation type="unfinished"></translation>
+        <translation>Bei Vererbung durch Vereinigung sind nur die Facetten %1 und %2 zulässig.</translation>
     </message>
     <message>
         <location line="+23"/>
         <location line="+16"/>
         <source>%1 contains %2 facet with invalid data: %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 enthält eine Facette %2 mit ungültigen Daten: %3.</translation>
     </message>
     <message>
         <location line="+24"/>
         <source>Attribute group %1 contains attribute %2 twice.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 enthält das Attribut %2 zweimal.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Attribute group %1 contains two different attributes that both have types derived from %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 enthält zwei verschiedene Attribute mit Typen, die von %2 abgeleitet sind.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Attribute group %1 contains attribute %2 that has value constraint but type that inherits from %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 enthält ein Attribut %2 mit einer Einschränkung des Werts, dessen Typ aber von %3 abgeleitet ist.</translation>
     </message>
     <message>
         <location line="+23"/>
         <source>Complex type %1 contains attribute %2 twice.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 enthält das Attribut %2 doppelt.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Complex type %1 contains two different attributes that both have types derived from %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 enthält zwei verschiedene Attribute mit Typen, die beide von %2 abgeleitet sind.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Complex type %1 contains attribute %2 that has value constraint but type that inherits from %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 enthält ein Attribut %2 mit einer Einschränkung des Werts, dessen Typ aber von %3 abgeleitet ist.</translation>
     </message>
     <message>
         <location line="+43"/>
         <source>Element %1 is not allowed to have a value constraint if its base type is complex.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 darf keine Einschränkung des Werts haben, wenn der Basistyp komplex ist.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Element %1 is not allowed to have a value constraint if its type is derived from %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 darf keine Einschränkung des Werts haben, wenn sein Typ von %2 abgeleitet ist.</translation>
     </message>
     <message>
         <location line="+10"/>
         <location line="+11"/>
         <source>Value constraint of element %1 is not of elements type: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Einschränkung des Werts des Elements %1 ist nicht vom Typ des Elements: %2.</translation>
     </message>
     <message>
         <location line="+13"/>
         <source>Element %1 is not allowed to have substitution group affiliation as it is no global element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 kann nicht zu einer Substitutionsgruppe gehören, da es kein globales Element ist.</translation>
     </message>
     <message>
         <location line="+28"/>
         <source>Type of element %1 cannot be derived from type of substitution group affiliation.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ des Elements %1 kann nicht vom Typ der zugehörigen Substitutionsgruppe abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+41"/>
         <source>Value constraint of attribute %1 is not of attributes type: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Einschränkung des Werts des Attributs %1 ist nicht vom Typ des Attributs: %2.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Attribute %1 has value constraint but has type derived from %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 hat eine Einschränkung des Werts, während sein Typ von %2 abgeleitet ist.</translation>
     </message>
     <message>
         <location line="+56"/>
         <source>%1 attribute in derived complex type must be %2 like in base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 in einem abgeleiteten komplexen Typ muss wie im Basistyp &apos;%2&apos; sein.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Attribute %1 in derived complex type must have %2 value constraint like in base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 in einem abgeleiteten komplexen Typ muss wie der Basistyp eine Einschränkung des Werts (%2) haben.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Attribute %1 in derived complex type must have the same %2 value constraint like in base type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 in einem abgeleiteten komplexen Typ muss die gleiche Einschränkung des Werts (%2) wie der Basistyp haben.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Attribute %1 in derived complex type must have %2 value constraint.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 in einem abgeleiteten komplexen Typ muss die Einschränkung des Werts &apos;%2&apos; haben.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>processContent of base wildcard must be weaker than derived wildcard.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das &apos;processContent&apos;-Attribut des Basisuchmusters muss schwächer sein als das des abgeleiteten Suchmusters.</translation>
     </message>
     <message>
         <location line="+39"/>
         <location line="+15"/>
         <source>Element %1 exists twice with different types.</source>
-        <translation type="unfinished"></translation>
+        <translation>Es existieren zwei Vorkommen verschiedenen Typs des Elements %1.</translation>
     </message>
     <message>
         <location line="+28"/>
         <source>Particle contains non-deterministic wildcards.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Partikel enthält nicht-deterministische Suchmuster.</translation>
     </message>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdschemahelper.cpp" line="+691"/>
         <location line="+63"/>
         <source>Base attribute %1 is required but derived attribute is not.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Basisattribut %1 ist erforderlich, nicht jedoch das abgeleitete Attribut.</translation>
     </message>
     <message>
         <location line="-57"/>
         <source>Type of derived attribute %1 cannot be validly derived from type of base attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ des abgeleiteten Attributs %1 kann nicht aus Typ des Basisattributs bestimmt werden.</translation>
     </message>
     <message>
         <location line="+28"/>
         <source>Value constraint of derived attribute %1 does not match value constraint of base attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Einschränkung des Werts des abgeleiteten Attributs %1 entspricht nicht der Einschränkung des Werts des Basisattributs.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>Derived attribute %1 does not exists in the base definition.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das abgeleitete Attribut %1 existiert in der Basisdefinition nicht.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Derived attribute %1 does not match the wildcard in the base definition.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das abgeleitete Attribut %1 entspricht nicht dem Suchmuster in der Basisdefinition.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Base attribute %1 is required but missing in derived definition.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das erforderliche Basisattribut %1 fehlt in der abgeleiteten Definition.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Derived definition contains an %1 element that does not exists in the base definition</source>
-        <translation type="unfinished"></translation>
+        <translation>Die abgeleitete Definition enthält ein Element %1, was in der Basisdefinition nicht existiert</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>Derived wildcard is not a subset of the base wildcard.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das abgeleitete Suchmuster ist keine Untermenge des Basissuchmusters.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>%1 of derived wildcard is not a valid restriction of %2 of base wildcard</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des abgeleiteten Suchmusters ist keine gültige Einschränkung des Attributs &apos;%2&apos; des Basissuchmusters</translation>
     </message>
     <message>
         <location line="+23"/>
         <source>Attribute %1 from base type is missing in derived type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Basistyps fehlt im abgeleiteten Typ.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>Type of derived attribute %1 differs from type of base attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ des abgeleiteten Attributs %1 unterscheidet sich vom Basistyp.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Base definition contains an %1 element that is missing in the derived definition</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 des Basistyps fehlt in der abgeleiteten Definition</translation>
     </message>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdschemaresolver.cpp" line="+354"/>
         <source>%1 references unknown %2 or %3 element %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 verweist auf ein unbekanntes Element %4 (&apos;%2&apos; oder &apos;%3&apos;).</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>%1 references identity constraint %2 that is no %3 or %4 element.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 verweist auf eine Identitätseinschränkung %2, die weder ein &apos;%3&apos; noch ein &apos;%4&apos; Element ist.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>%1 has a different number of fields from the identity constraint %2 that it references.</source>
-        <translation type="unfinished"></translation>
+        <translation>Bei %1 unterscheidet sich die Anzahl der Felder von der der Identitätseinschränkung %2, auf die es verweist.</translation>
     </message>
     <message>
         <location line="+23"/>
         <source>Base type %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="+84"/>
         <source>Item type %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Subtyp %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="+31"/>
         <source>Member type %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Subtyp %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="+28"/>
         <location line="+408"/>
         <location line="+30"/>
         <source>Type %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="-416"/>
         <source>Base type %1 of complex type cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Basistyp %1 des komplexen Typs kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>%1 cannot have complex base type that has a %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 kann keinen komplexen Basistyp haben, der &apos;%2&apos; spezifiziert.</translation>
     </message>
     <message>
         <location line="+279"/>
         <source>Content model of complex type %1 contains %2 element so it cannot be derived by extension from a non-empty type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Inhaltsmodell des komplexen Typs %1enthält ein Element &apos;%2&apos;; es kann daher nicht durch Erweiterung von einem nichtleeren Typ abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Complex type %1 cannot be derived by extension from %2 as the latter contains %3 element in its content model.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ % kann nicht durch Erweiterung von %2 abgeleitet werden, da letzterer ein &apos;%3&apos;-Element in seinem Inhaltsmodell hat.</translation>
     </message>
     <message>
         <location line="+101"/>
         <source>Type of %1 element must be a simple type, %2 is not.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ des Elements %1 muss ein einfacher Typ sein, was %2 nicht ist.</translation>
     </message>
     <message>
         <location line="+62"/>
         <source>Substitution group %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Substitutionsgruppe %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Substitution group %1 has circular definition.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Substitutionsgruppe %1 hat eine zirkuläre Definition.</translation>
     </message>
     <message>
         <location line="+120"/>
         <location line="+7"/>
         <source>Duplicated element names %1 in %2 element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Elementname %1 kommt im Element %2 mehrfach vor.</translation>
     </message>
     <message>
         <location line="+29"/>
@@ -9036,207 +9045,207 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <location line="+71"/>
         <location line="+28"/>
         <source>Reference %1 of %2 element cannot be resolved.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Verweis %1 des Elements %2 kann nicht aufgelöst werden.</translation>
     </message>
     <message>
         <location line="-138"/>
         <source>Circular group reference for %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Zirkulärer Verweis bei %1.</translation>
     </message>
     <message>
         <location line="+16"/>
         <source>%1 element is not allowed in this scope</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist in diesem Bereich nicht zulässig</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>%1 element cannot have %2 attribute with value other than %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Wert des Attributs %2 des Elements %1 kann nur %3 sein.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>%1 element cannot have %2 attribute with value other than %3 or %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Wert des Attributs %2 des Elements %1 kann nur %3 oder %4 sein.</translation>
     </message>
     <message>
         <location line="+91"/>
         <source>%1 or %2 attribute of reference %3 does not match with the attribute declaration %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 oder %2 des Verweises %3 entspricht nicht der Attributsdeklaration %4.</translation>
     </message>
     <message>
         <location line="+25"/>
         <source>Attribute group %1 has circular reference.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 hat einen zirkulären Verweis.</translation>
     </message>
     <message>
         <location line="+131"/>
         <source>%1 attribute in %2 must have %3 use like in base type %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 aus %2 muss die Verwendung &apos;%3&apos; spezifizieren, wie im Basistyp %4.</translation>
     </message>
     <message>
         <location line="+52"/>
         <source>Attribute wildcard of %1 is not a valid restriction of attribute wildcard of base type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attributssuchmuster %1 ist keine gültige Einschränkung des Attributssuchmuster des Basistyps %2.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>%1 has attribute wildcard but its base type %2 has not.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 hat ein Attributssuchmuster, nicht jedoch sein Basistyp %2.</translation>
     </message>
     <message>
         <location line="+26"/>
         <source>Union of attribute wildcard of type %1 and attribute wildcard of its base type %2 is not expressible.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Vereinigung der Attributssuchmuster des Typs %1 und seines Basistyps %2 ergibt keinen gültigen Ausdruck.</translation>
     </message>
     <message>
         <location line="+48"/>
         <source>Enumeration facet contains invalid content: {%1} is not a value of type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Ungültiger Inhalt einer Aufzählungsfacette: {%1} ist kein Wert des Typs %2.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>Namespace prefix of qualified name %1 is not defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Namensraum-Präfix des qualifizierten Namens %1 ist nicht definiert.</translation>
     </message>
     <message>
         <location line="+51"/>
         <location line="+18"/>
         <source>%1 element %2 is not a valid restriction of the %3 element it redefines: %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %2 (%1) ist keine gültige Einschränkung des überschriebenen Elements (%3): %4.</translation>
     </message>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdparticlechecker.cpp" line="+165"/>
         <source>Empty particle cannot be derived from non-empty particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Von einem nichtleeren Partikel kann kein leerer Partikel abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+15"/>
         <source>Derived particle is missing element %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 fehlt im abgeleiteten Partikel.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Derived element %1 is missing value constraint as defined in base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Im abgeleiteten Element %1 fehlt Einschränkung des Wertes, wie sie im Basispartikel definiert ist.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>Derived element %1 has weaker value constraint than base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das abgeleitete Element %1 hat eine schwächere Einschränkung des Wertes als der Basispartikel.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Fixed value constraint of element %1 differs from value constraint in base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die feste Einschränkung des Wertes des Elements %1 unterscheidet sich von der Einschränkung des Wertes des Basispartikels.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Derived element %1 cannot be nillable as base element is not nillable.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das abgeleitete Element %1 kann kein &apos;nillable&apos;-Attribut haben, da das Basiselement keines spezifiziert.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>Block constraints of derived element %1 must not be more weaker than in the base element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Blockeinschränkung des abgeleiteten Elements %1 darf nicht schwächer sein als im Basiselement.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Simple type of derived element %1 cannot be validly derived from base element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der einfache Typ des abgeleiteten Elements %1 kann nicht vom Basiselement abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>Complex type of derived element %1 cannot be validly derived from base element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ des abgeleiteten Elements %1 kann nicht vom Basiselement abgeleitet werden.</translation>
     </message>
     <message>
         <location line="+24"/>
         <source>Element %1 is missing in derived particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 fehlt im abgeleiteten Partikel.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Element %1 does not match namespace constraint of wildcard in base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 entspricht nicht der Namensraumeinschränkung des Basispartikels.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Wildcard in derived particle is not a valid subset of wildcard in base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Suchmuster im abgeleiteten Partikel ist keine gültige Untermenge des Suchmusters des Basispartikels.</translation>
     </message>
     <message>
         <location line="+5"/>
         <source>processContent of wildcard in derived particle is weaker than wildcard in base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das processContent-Attribut des Suchmusters des abgeleiteten Partikels ist schwächer als das Suchmuster des Basispartikels.</translation>
     </message>
     <message>
         <location line="+240"/>
         <source>Derived particle allows content that is not allowed in the base particle.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der abgeleitete Partikel gestattet Inhalt, der für den Basispartikel nicht zulässig ist.</translation>
     </message>
     <message>
-        <location filename="../src/xmlpatterns/schema/qxsdschemaparser.cpp" line="+169"/>
+        <location filename="../src/xmlpatterns/schema/qxsdschemaparser.cpp" line="+170"/>
         <source>Can not process unknown element %1, expected elements are: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das unbekannte Element %1 kann nicht verarbeitet werden; zulässig wären: %2.</translation>
     </message>
     <message>
         <location line="+13"/>
         <source>Element %1 is not allowed in this scope, possible elements are: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist in diesem Bereich nicht zulässig; möglich wären: %2.</translation>
     </message>
     <message>
         <location line="+16"/>
         <source>Child element is missing in that scope, possible child elements are: %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Unterelement fehlt im Bereich; mögliche Unterelemente wären: %1.</translation>
     </message>
     <message>
         <location line="+127"/>
         <source>Document is not a XML schema.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Dokument ist kein XML-Schema.</translation>
     </message>
     <message>
         <location line="+22"/>
         <source>%1 attribute of %2 element contains invalid content: {%3} is not a value of type %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 enthält ungültigen Inhalt: {%3} ist kein Wert des Typs %4.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>%1 attribute of %2 element contains invalid content: {%3}.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 enthält ungültigen Inhalt: {%3}.</translation>
     </message>
     <message>
         <location line="+26"/>
         <source>Target namespace %1 of included schema is different from the target namespace %2 as defined by the including schema.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zielnamensraum %1 des eingebundenen Schemas unterscheidet sich vom dem von ihm definierten Zielnamensraum %2.</translation>
     </message>
     <message>
         <location line="+14"/>
         <location line="+11"/>
         <source>Target namespace %1 of imported schema is different from the target namespace %2 as defined by the importing schema.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zielnamensraum %1 des importierten Schemas unterscheidet sich vom dem von ihm definierten Zielnamensraum %2.</translation>
     </message>
     <message>
         <location line="+237"/>
         <source>%1 element is not allowed to have the same %2 attribute value as the target namespace %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 kann nicht den Zielnamensraum %3 als Wert des Attributs &apos;%2&apos; spezifizieren.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>%1 element without %2 attribute is not allowed inside schema without target namespace.</source>
-        <translation type="unfinished"></translation>
+        <translation>In einem Schema ohne Namensraum muss das Element %1 ein Attribut %2 haben.</translation>
     </message>
     <message>
         <location line="+833"/>
         <location line="+158"/>
         <source>%1 element is not allowed inside %2 element if %3 attribute is present.</source>
-        <translation type="unfinished"></translation>
+        <translation>Wenn das Attribut %3 vorhanden ist, darf das Element %1 nicht im Element %2 vorkommen.</translation>
     </message>
     <message>
         <location line="-97"/>
         <location line="+119"/>
         <location line="+92"/>
         <source>%1 element has neither %2 attribute nor %3 child element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 hat weder das Attribut %2 noch ein Unterelement %3.</translation>
     </message>
     <message>
         <location line="+835"/>
@@ -9254,23 +9263,23 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <location line="+11"/>
         <location line="+11"/>
         <source>%1 element with %2 child element must not have a %3 attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 darf kein Attribut %3 haben, wenn das Unterelement %2 vorhanden ist.</translation>
     </message>
     <message>
         <location line="-1325"/>
         <source>%1 attribute of %2 element must be %3 or %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 kann nur %3 oder %4 sein.</translation>
     </message>
     <message>
         <location line="+36"/>
         <source>%1 attribute of %2 element must have a value of %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 muss den Wert %3 haben.</translation>
     </message>
     <message>
         <location line="+7"/>
         <location line="+34"/>
         <source>%1 attribute of %2 element must have a value of %3 or %4.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 kann nur einen der Werte %3 oder %4 haben.</translation>
     </message>
     <message>
         <location line="+319"/>
@@ -9288,626 +9297,626 @@ Bitte wählen Sie einen anderen Dateinamen.</translation>
         <location line="+6"/>
         <location line="+77"/>
         <source>%1 element must not have %2 and %3 attribute together.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attribute %2 und %3 können nicht zusammen im Element %1 erscheinen.</translation>
     </message>
     <message>
         <location line="-768"/>
         <location line="+222"/>
         <source>Content of %1 attribute of %2 element must not be from namespace %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des Attributs %1 des Elements %2 kann nicht vom Namensraum %3 stammen.</translation>
     </message>
     <message>
         <location line="-215"/>
         <location line="+222"/>
         <source>%1 attribute of %2 element must not be %3.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 kann nicht %3 sein.</translation>
     </message>
     <message>
         <location line="-64"/>
         <source>%1 attribute of %2 element must have the value %3 because the %4 attribute is set.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 muss den Wert %3 haben, da das Attribut %4 gesetzt ist.</translation>
     </message>
     <message>
         <location line="+187"/>
         <source>Specifying use=&apos;prohibited&apos; inside an attribute group has no effect.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe von use=&apos;prohibited&apos; in einer Attributgruppe hat keinerlei Auswirkungen.</translation>
     </message>
     <message>
         <location line="+353"/>
         <source>%1 element must have either %2 or %3 attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 muss eines der Attribute %2 oder %3 spezifizieren.</translation>
     </message>
     <message>
         <location line="+554"/>
         <source>%1 element must have either %2 attribute or %3 or %4 as child element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 muss entweder das Attribut %2 spezifizieren oder über eines der Unterelemente %3 oder %4 verfügen.</translation>
     </message>
     <message>
         <location line="+55"/>
         <source>%1 element requires either %2 or %3 attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 erfordert eines der Attribute %2 oder %3.</translation>
     </message>
     <message>
         <location line="+19"/>
         <source>Text or entity references not allowed inside %1 element</source>
-        <translation type="unfinished"></translation>
+        <translation>Text- oder Entitätsreferenzen sind innerhalb eines %1-Elements nicht zulässig.</translation>
     </message>
     <message>
         <location line="+41"/>
         <location line="+112"/>
         <source>%1 attribute of %2 element must contain %3, %4 or a list of URIs.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 des Elements %2 muss %3, %4 oder eine Liste der URIs enthalten.</translation>
     </message>
     <message>
         <location line="+126"/>
         <source>%1 element is not allowed in this context.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist in diesem Kontext nicht zulässig.</translation>
     </message>
     <message>
         <location line="+53"/>
         <source>%1 attribute of %2 element has larger value than %3 attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Wert des Attributs %1 des Elements %2 ist größer als der des Attributs %3.</translation>
     </message>
     <message>
         <location line="+25"/>
         <source>Prefix of qualified name %1 is not defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Präfix des qualifizierten Namens %1 ist nicht definiert.</translation>
     </message>
     <message>
         <location line="+65"/>
         <location line="+61"/>
         <source>%1 attribute of %2 element must either contain %3 or the other values.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Wert des Attributs %1 des Elements %2 muss entweder %3 oder die anderen Werte enthalten.</translation>
     </message>
     <message>
         <location line="+131"/>
         <source>Component with id %1 has been defined previously.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Komponente mit der Id %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Element %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Attribute %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+15"/>
         <source>Type %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Typ %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+23"/>
         <source>Attribute group %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Attributgruppe %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Element group %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Elementgruppe %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Notation %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Notation %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Identity constraint %1 already defined.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Identitätseinschränkung %1 ist bereits definiert.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Duplicated facets in simple type %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Im einfachen Typ %1 kommen Facetten mehrfach vor.</translation>
     </message>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdtypechecker.cpp" line="+233"/>
         <location line="+7"/>
         <location line="+21"/>
         <source>%1 is not valid according to %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 ist nach %2 ungültig.</translation>
     </message>
     <message>
         <location line="+167"/>
         <source>String content does not match the length facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zeichenketteninhalt entspricht nicht der Längenfacette.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>String content does not match the minLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zeichenketteninhalt entspricht nicht der Längenfacette (Minimumangabe).</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>String content does not match the maxLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zeichenketteninhalt entspricht nicht der Längenfacette (Maximumangabe).</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>String content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zeichenketteninhalt entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>String content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Zeichenketteninhalt ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Signed integer content does not match the maxInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Facette &apos;maxInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Signed integer content does not match the maxExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Facette &apos;maxExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Signed integer content does not match the minInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Facette &apos;minInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Signed integer content does not match the minExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Facette &apos;minExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Signed integer content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Signed integer content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Signed integer content does not match in the totalDigits facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenbehaftete Ganzzahlwert entspricht nicht der Facette &apos;totalDigits&apos;.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Unsigned integer content does not match the maxInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Facette &apos;maxInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Unsigned integer content does not match the maxExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Facette &apos;maxExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Unsigned integer content does not match the minInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Facette &apos;minInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Unsigned integer content does not match the minExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Facette &apos;minExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Unsigned integer content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Unsigned integer content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Unsigned integer content does not match in the totalDigits facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der vorzeichenlose Ganzzahlwert entspricht nicht der Facette &apos;totalDigits&apos;.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Double content does not match the maxInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl entspricht nicht der Facette &apos;maxInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Double content does not match the maxExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl entspricht nicht der Facette &apos;maxExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Double content does not match the minInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl entspricht nicht der Facette &apos;minInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Double content does not match the minExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl entspricht nicht der Facette &apos;minExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Double content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Double content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Gleitkommazahl entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Decimal content does not match in the fractionDigits facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Dezimalzahl entspricht nicht der Facette &apos;fractionDigit&apos;.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Decimal content does not match in the totalDigits facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Dezimalzahl entspricht nicht der Facette &apos;totalDigits&apos;.</translation>
     </message>
     <message>
         <location line="+14"/>
         <source>Date time content does not match the maxInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe entspricht nicht der Facette &apos;maxInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Date time content does not match the maxExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe entspricht nicht der Facette &apos;maxExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Date time content does not match the minInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe entspricht nicht der Facette &apos;minInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Date time content does not match the minExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe entspricht nicht der Facette &apos;minExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Date time content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Date time content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Datumsangabe entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+15"/>
         <source>Duration content does not match the maxInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer entspricht nicht der Facette &apos;maxInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Duration content does not match the maxExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer entspricht nicht der Facette &apos;maxExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Duration content does not match the minInclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer entspricht nicht der Facette &apos;minInclusive&apos;.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Duration content does not match the minExclusive facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer entspricht nicht der Facette &apos;minExclusive&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Duration content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Duration content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Angabe der Zeitdauer entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+27"/>
         <source>Boolean content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Boolesche Wert entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>Binary content does not match the length facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der binäre Inhalt entspricht nicht der Längenfacette.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Binary content does not match the minLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der binäre Inhalt entspricht nicht der Facette &apos;minLength&apos;.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Binary content does not match the maxLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der binäre Inhalt entspricht nicht der Facette &apos;maxLength&apos;.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Binary content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der binäre Inhalt ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+27"/>
         <source>Invalid QName content: %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des qualifizierten Namens ist ungültig: %1.</translation>
     </message>
     <message>
         <location line="+17"/>
         <source>QName content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des qualifizierten Namens ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>QName content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des qualifizierten Namens entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+36"/>
         <source>Notation content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt der Notation ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+19"/>
         <source>List content does not match length facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Listeninhalt entspricht nicht der Längenfacette.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>List content does not match minLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Listeninhalt entspricht nicht der Facette &apos;minLength&apos;.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>List content does not match maxLength facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Listeninhalt entspricht nicht der Facette &apos;maxLength&apos;.</translation>
     </message>
     <message>
         <location line="+90"/>
         <source>List content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Listeninhalt ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>List content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Listeninhalt entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+39"/>
         <source>Union content is not listed in the enumeration facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt der Vereinigung ist nicht in der Aufzählungsfacette enthalten.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Union content does not match pattern facet.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt der Vereinigung entspricht nicht der Suchmusterfacette.</translation>
     </message>
     <message>
         <location line="+15"/>
         <source>Data of type %1 are not allowed to be empty.</source>
-        <translation type="unfinished"></translation>
+        <translation>Daten vom Typ %1 können nicht leer sein.</translation>
     </message>
     <message>
         <location filename="../src/xmlpatterns/schema/qxsdvalidatinginstancereader.cpp" line="+160"/>
         <source>Element %1 is missing child element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Beim Element %1 fehlt ein Unterelement.</translation>
     </message>
     <message>
         <location line="+16"/>
         <source>There is one IDREF value with no corresponding ID: %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Es existiert ein IDREF-Wert, für den keine zugehörige ID vorhanden ist: %1.</translation>
     </message>
     <message>
         <location line="+27"/>
         <source>Loaded schema file is invalid.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das geladene Schema ist ungültig.</translation>
     </message>
     <message>
         <location line="+16"/>
         <source>%1 contains invalid data.</source>
-        <translation type="unfinished"></translation>
+        <translation>%1 enthält ungültige Daten.</translation>
     </message>
     <message>
         <location line="+13"/>
         <source>xsi:schemaLocation namespace %1 has already appeared earlier in the instance document.</source>
-        <translation type="unfinished"></translation>
+        <translation>xsi:schemaLocation namespace %1 wurde im Instanzdokument bereits spezifiziert.</translation>
     </message>
     <message>
         <location line="+22"/>
         <source>xsi:noNamespaceSchemaLocation cannot appear after the first no-namespace element or attribute.</source>
-        <translation type="unfinished"></translation>
+        <translation>xsi:noNamespaceSchemaLocation kann nicht nach dem ersten Element oder Attribut ohne Namensraum erscheinen.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>No schema defined for validation.</source>
-        <translation type="unfinished"></translation>
+        <translation>Es ist kein Schema für die Validierung definiert.</translation>
     </message>
     <message>
         <location line="+10"/>
         <source>No definition for element %1 available.</source>
-        <translation type="unfinished"></translation>
+        <translation>Für das Element %1 ist keine Definition verfügbar.</translation>
     </message>
     <message>
         <location line="+18"/>
         <location line="+49"/>
         <location line="+142"/>
         <source>Specified type %1 is not known to the schema.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der angegebene Typ %1 ist im Schema nicht spezifiziert.</translation>
     </message>
     <message>
         <location line="-176"/>
         <source>Element %1 is not defined in this scope.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist in diesem Bereich nicht definiert.</translation>
     </message>
     <message>
         <location line="+43"/>
         <source>Declaration for element %1 does not exist.</source>
-        <translation type="unfinished"></translation>
+        <translation>Für das Element %1 ist keine Deklaration verfügbar.</translation>
     </message>
     <message>
         <location line="+12"/>
         <source>Element %1 contains invalid content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält ungültigen Inhalt.</translation>
     </message>
     <message>
         <location line="+73"/>
         <source>Element %1 is declared as abstract.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 ist als abstrakt deklariert.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Element %1 is not nillable.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 hat das Attribut &apos;nillable&apos; nicht spezifiziert.</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Attribute %1 contains invalid data: %2</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 enthält ungültigeDaten: %2</translation>
     </message>
     <message>
         <location line="+8"/>
         <source>Element contains content although it is nillable.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element hat Inhalt, obwohl es &apos;nillable&apos; spezifiziert.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Fixed value constrained not allowed if element is nillable.</source>
-        <translation type="unfinished"></translation>
+        <translation>Eine feste Einschränkung des Werts ist nicht zulässig, wenn das Element &apos;nillable&apos; spezifiert.</translation>
     </message>
     <message>
         <location line="+32"/>
         <source>Specified type %1 is not validly substitutable with element type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der angebenene Typ %1 kann nicht durch den Elementtyp %2 substituiert werden.</translation>
     </message>
     <message>
         <location line="+23"/>
         <source>Complex type %1 is not allowed to be abstract.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der komplexe Typ %1 kann nicht abstrakt sein.</translation>
     </message>
     <message>
         <location line="+21"/>
         <source>Element %1 contains not allowed attributes.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält unzulässige Attribute.</translation>
     </message>
     <message>
         <location line="+6"/>
         <location line="+97"/>
         <source>Element %1 contains not allowed child element.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält ein unzulässiges Unterelement.</translation>
     </message>
     <message>
         <location line="-76"/>
         <location line="+93"/>
         <source>Content of element %1 does not match its type definition: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des Elements %1 entspricht nicht seiner Typdefinition: %2.</translation>
     </message>
     <message>
         <location line="-85"/>
         <location line="+92"/>
         <location line="+41"/>
         <source>Content of element %1 does not match defined value constraint.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des Elements %1 entspricht nicht der definierten Einschränkung des Werts.</translation>
     </message>
     <message>
         <location line="-73"/>
         <source>Element %1 contains not allowed child content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält unzulässigen Unterinhalt.</translation>
     </message>
     <message>
         <location line="+41"/>
         <source>Element %1 contains not allowed text content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält unzulässigen Textinhalt.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Element %1 can not contain other elements, as it has a fixed content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 darf kann keine Unterelemente haben, da es festen Inhalt enthält.</translation>
     </message>
     <message>
         <location line="+43"/>
         <source>Element %1 is missing required attribute %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Bei dem Element %1 fehlt ein erforderliches Attribut %2.</translation>
     </message>
     <message>
         <location line="+29"/>
         <source>Attribute %1 does not match the attribute wildcard.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 entspricht nicht dem Attributssuchmuster.</translation>
     </message>
     <message>
         <location line="+9"/>
         <source>Declaration for attribute %1 does not exist.</source>
-        <translation type="unfinished"></translation>
+        <translation>Für das Attribut %1 ist keine Deklaration verfügbar.</translation>
     </message>
     <message>
         <location line="+6"/>
         <source>Element %1 contains two attributes of type %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält zwei Attribute des Typs %2.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>Attribute %1 contains invalid content.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut %1 enthält ungültigen Inhalt.</translation>
     </message>
     <message>
         <location line="+7"/>
         <source>Element %1 contains unknown attribute %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Element %1 enthält ein unbekanntes Attribut %2.</translation>
     </message>
     <message>
         <location line="+40"/>
         <location line="+46"/>
         <source>Content of attribute %1 does not match its type definition: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des Attributs %1 entspricht nicht seiner Typdefinition: %2.</translation>
     </message>
     <message>
         <location line="-38"/>
         <location line="+46"/>
         <source>Content of attribute %1 does not match defined value constraint.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der Inhalt des Attributs %1 entspricht nicht der definierten Einschränkung des Werts.</translation>
     </message>
     <message>
         <location line="+88"/>
         <source>Non-unique value found for constraint %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Für die Einschränkung %1 wurde ein nicht eindeutiger Wert gefunden.</translation>
     </message>
     <message>
         <location line="+20"/>
         <source>Key constraint %1 contains absent fields.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Einschränkung des Schlüssels %1 enthält nicht vorhandene Felder.</translation>
     </message>
     <message>
         <location line="+18"/>
         <source>Key constraint %1 contains references nillable element %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Die Einschränkung des Schlüssels %1 verweist auf das Element %2, was &apos;nillable&apos; spezifiziert.</translation>
     </message>
     <message>
         <location line="+40"/>
         <source>No referenced value found for key reference %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der referenzierte Wert der Schlüsselreferenz %1 konnte nicht gefunden werden.</translation>
     </message>
     <message>
         <location line="+64"/>
         <source>More than one value found for field %1.</source>
-        <translation type="unfinished"></translation>
+        <translation>Für das Feld %1 wurden mehrere Werte gefunden.</translation>
     </message>
     <message>
         <location line="+20"/>
         <source>Field %1 has no simple type.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Feld %1 hat keinen einfachen Typ.</translation>
     </message>
     <message>
         <location line="+73"/>
         <source>ID value &apos;%1&apos; is not unique.</source>
-        <translation type="unfinished"></translation>
+        <translation>Der ID-Wert &apos;%1&apos; ist nicht eindeutig.</translation>
     </message>
     <message>
         <location line="+11"/>
         <source>&apos;%1&apos; attribute contains invalid QName content: %2.</source>
-        <translation type="unfinished"></translation>
+        <translation>Das Attribut &apos;%1&apos; enthält einen ungültigen qualifizierten Namen: %2.</translation>
     </message>
 </context>
 </TS>
-- 
cgit v0.12


From a95375593228e00186dbd50a04736bb32a24730e Mon Sep 17 00:00:00 2001
From: Janne Anttila <janne.anttila@digia.com>
Date: Tue, 20 Oct 2009 12:37:27 +0300
Subject: Doc update for QDir::rootPath and QDir::homePath in Symbian.

Task-number: QTBUG-4867
Reviewed-by: Aleksandar Sasha Babic
---
 src/corelib/io/qdir.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/corelib/io/qdir.cpp b/src/corelib/io/qdir.cpp
index a67b3bd..59db9a6 100644
--- a/src/corelib/io/qdir.cpp
+++ b/src/corelib/io/qdir.cpp
@@ -1930,7 +1930,7 @@ QString QDir::currentPath()
 
     Under non-Windows operating systems the \c HOME environment
     variable is used if it exists, otherwise the path returned by the
-    rootPath().
+    rootPath(). On Symbian always the same as the path returned by the rootPath().
 
     \sa home(), currentPath(), rootPath(), tempPath()
 */
@@ -2002,7 +2002,8 @@ QString QDir::tempPath()
     Returns the absolute path of the root directory.
 
     For Unix operating systems this returns "/". For Windows file
-    systems this normally returns "c:/".
+    systems this normally returns "c:/". On Symbian this typically returns
+    "c:/data", i.e. the same as native PathInfo::PhoneMemoryRootPath().
 
     \sa root(), drives(), currentPath(), homePath(), tempPath()
 */
-- 
cgit v0.12


From ccb376e04c29c4a9214f71c173c81f5877dc9502 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Tue, 20 Oct 2009 11:44:36 +0200
Subject: changes-4.6.0 updated

---
 dist/changes-4.6.0 | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/dist/changes-4.6.0 b/dist/changes-4.6.0
index cd9f130..7f723da 100644
--- a/dist/changes-4.6.0
+++ b/dist/changes-4.6.0
@@ -49,6 +49,12 @@ information about a particular change.
    QRegion. The native handle is for reading out only. Any GDI calls
    made on the HRGN handle will not affect the QRegion.
 
+ - [259221] QFileInfo::symLinkTarget() now supports NTFS symbolic links
+   thanks to Konstantin Ritt (merge request 1217).
+
+ - The reading code of QLocalSocket on Windows has been rewritten to improve
+   reading performance.
+
 ****************************************************************************
 * Important Behavior Changes *
 ****************************************************************************
-- 
cgit v0.12


From f779d9f7e317ff3e10f015a05d349e1fa3e7ab84 Mon Sep 17 00:00:00 2001
From: Dean Dettman <dean.dettman@nokia.com>
Date: Tue, 20 Oct 2009 12:28:32 +0200
Subject: make missing Key_Back and Key_Forward menu glyphs return 0  on
 mac(cocoa)

This is an addition to
commit 5651d2547261ccecbf50f8141c634f59c0adc00d to make it obvious that
in cocoa nothing is returned.

Task-number: QTBUG-4873
Reviewed-by: MortenS
---
 src/gui/widgets/qmenu_mac.mm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/widgets/qmenu_mac.mm b/src/gui/widgets/qmenu_mac.mm
index 0f92ad9..ec9313f 100644
--- a/src/gui/widgets/qmenu_mac.mm
+++ b/src/gui/widgets/qmenu_mac.mm
@@ -1244,9 +1244,9 @@ NSString *keySequenceToKeyEqivalent(const QKeySequence &accel)
     else if (accel_key == Qt::Key_End)
         keyEquiv[0] = NSEndFunctionKey;
     else if (accel_key == Qt::Key_Back)
-        keyEquiv[0] = kMenuLeftArrowDashedGlyph;  // ### Cocoa has no equivalent - no icon is displayed
+        keyEquiv[0] = 0 ; // ### could not find Cocoa equivalent to kMenuLeftArrowDashedGlyph
     else if (accel_key == Qt::Key_Forward)
-        keyEquiv[0] = kMenuRightArrowDashedGlyph;  // ### Cocoa has no equivalent - no icon is displayed
+        keyEquiv[0] = 0 ; // ### could not find Cocoa equivalent to kMenuRightArrowDashedGlyph
     else
         keyEquiv[0] = unichar(QChar(accel_key).toLower().unicode());
     return [NSString stringWithCharacters:keyEquiv length:1];
-- 
cgit v0.12


From da3e89e8d98a4d3322eae94aafd38ddb444f144e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sami=20Meril=C3=A4?= <sami.merila@nokia.com>
Date: Tue, 20 Oct 2009 13:31:33 +0300
Subject: QT-693 QS60Style does not regard selection beahviors with itemviews

QS60Style disregards all selection behaviors for itemviews. This leads
to error when showing a highlighted selection rect; rect is only shown
for cell having focus.

Fixed by setting the highlight to all 'selected' cells.

Task-number: QT-693
Reviewed-by: Alessandro Portale
---
 src/gui/styles/qs60style.cpp | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/gui/styles/qs60style.cpp b/src/gui/styles/qs60style.cpp
index 4fa1d03..6d95336 100644
--- a/src/gui/styles/qs60style.cpp
+++ b/src/gui/styles/qs60style.cpp
@@ -1313,7 +1313,7 @@ void QS60Style::drawControl(ControlElement element, const QStyleOption *option,
             painter->save();
 
             painter->setClipRect(voptAdj.rect);
-            const bool isSelected = (voptAdj.state & QStyle::State_HasFocus);
+            const bool isSelected = (vopt->state & QStyle::State_Selected);
 
             bool isVisible = false;
             int scrollBarWidth = 0;
@@ -1358,7 +1358,27 @@ void QS60Style::drawControl(ControlElement element, const QStyleOption *option,
 
             // draw the focus rect
             if (isSelected) {
-                const QRect highlightRect = option->rect.adjusted(1,1,-1,-1);
+                QRect highlightRect = option->rect.adjusted(1,1,-1,-1);
+                const QAbstractItemView *view = qobject_cast<const QAbstractItemView *>(widget);
+                if (view && view->selectionBehavior() != QAbstractItemView::SelectItems) {
+                    // set highlight rect so that it is continuous from cell to cell, yet sligthly
+                    // smaller than cell rect
+                    int xBeginning = 0, yBeginning = 0, xEnd = 0, yEnd = 0;
+                    if (view->selectionBehavior() == QAbstractItemView::SelectRows) {
+                        yBeginning = 1; yEnd = -1;
+                        if (vopt->viewItemPosition == QStyleOptionViewItemV4::Beginning)
+                            xBeginning = 1;
+                        else if (vopt->viewItemPosition == QStyleOptionViewItemV4::End)
+                            xEnd = -1;
+                    } else if (view->selectionBehavior() == QAbstractItemView::SelectColumns) {
+                        xBeginning = 1; xEnd = -1;
+                        if (vopt->viewItemPosition == QStyleOptionViewItemV4::Beginning)
+                            yBeginning = 1;
+                        else if (vopt->viewItemPosition == QStyleOptionViewItemV4::End)
+                            yEnd = -1;
+                    }
+                    highlightRect = option->rect.adjusted(xBeginning, yBeginning, xEnd, xBeginning);
+                }
                 QS60StylePrivate::drawSkinElement(QS60StylePrivate::SE_ListHighlight, painter, highlightRect, flags);
             }
 
-- 
cgit v0.12


From f7d826f1a42c912f1db15da0a1cefe13bdd54906 Mon Sep 17 00:00:00 2001
From: Shane Kearns <shane.kearns@sosco.com>
Date: Tue, 20 Oct 2009 13:34:55 +0200
Subject: Use premultiplied alpha pixel format in Symbian

Gives better performance in the raster paint engine.
For Symbian 9.3 onwards, this can also be used as the native pixmap
format. For 9.2, conversion is required.

Reviewed-by: Sami Merila
Reviewed-by: Jani Hautakangas
---
 src/gui/image/qpixmap_s60.cpp          | 19 +++++++++++------
 src/gui/kernel/qapplication_s60.cpp    |  7 ++++++
 src/gui/kernel/qt_s60_p.h              | 10 +++++----
 src/gui/styles/qs60style_s60.cpp       |  7 +++---
 src/s60installs/eabi/QtGuiu.def        | 39 ++++++++++++++++++++++++++++------
 src/s60installs/eabi/QtMultimediau.def |  6 ++++--
 src/s60installs/eabi/QtNetworku.def    |  2 ++
 src/s60installs/eabi/QtScriptu.def     |  1 +
 src/s60installs/eabi/QtXmlu.def        |  1 -
 src/s60installs/eabi/phononu.def       | 10 +++++++++
 tests/auto/qpixmap/tst_qpixmap.cpp     |  2 +-
 11 files changed, 78 insertions(+), 26 deletions(-)

diff --git a/src/gui/image/qpixmap_s60.cpp b/src/gui/image/qpixmap_s60.cpp
index 9ae8d72..666d608 100644
--- a/src/gui/image/qpixmap_s60.cpp
+++ b/src/gui/image/qpixmap_s60.cpp
@@ -496,11 +496,12 @@ void QS60PixmapData::fromImage(const QImage &img, Qt::ImageConversionFlags flags
         mode = EColor16MU;
         break;
     case QImage::Format_ARGB32_Premultiplied:
-#if !defined(__SERIES60_31__) && !defined(__S60_32__)
-        mode = EColor16MAP;
-        break;
-#endif
-        destFormat = QImage::Format_ARGB32;
+        if (S60->supportsPremultipliedAlpha) {
+            mode = Q_SYMBIAN_ECOLOR16MAP;
+            break;
+        } else {
+            destFormat = QImage::Format_ARGB32;
+        }
         // Fall through intended
     case QImage::Format_ARGB32:
         mode = EColor16MA;
@@ -690,6 +691,10 @@ void QS60PixmapData::beginDataAccess()
     bytes = newBytes;
     TDisplayMode mode = cfbsBitmap->DisplayMode();
     QImage::Format format = qt_TDisplayMode2Format(mode);
+    //on S60 3.1, premultiplied alpha pixels are stored in a bitmap with 16MA type
+    if (format == QImage::Format_ARGB32)
+        format = QImage::Format_ARGB32_Premultiplied; // pixel data is actually in premultiplied format
+
     TSize size = cfbsBitmap->SizeInPixels();
 
     QVector<QRgb> savedColorTable;
@@ -794,8 +799,8 @@ void* QS60PixmapData::toNativeType(NativeType type)
         bool needsCopy = false;
 
         QSysInfo::SymbianVersion symbianVersion = QSysInfo::symbianVersion();
-        if (symbianVersion == QSysInfo::SV_9_2 || symbianVersion == QSysInfo::SV_9_3) {
-            // Convert argb32_premultiplied to argb32 since Symbian 9.2 and Symbian 9.3 do
+        if (!(S60->supportsPremultipliedAlpha)) {
+            // Convert argb32_premultiplied to argb32 since Symbian 9.2 does
             // not support premultipied format.
 
             if (image.format() == QImage::Format_ARGB32_Premultiplied) {
diff --git a/src/gui/kernel/qapplication_s60.cpp b/src/gui/kernel/qapplication_s60.cpp
index cb9dda4..656bbc9 100644
--- a/src/gui/kernel/qapplication_s60.cpp
+++ b/src/gui/kernel/qapplication_s60.cpp
@@ -1056,6 +1056,13 @@ void qt_init(QApplicationPrivate * /* priv */, int)
     TDisplayMode mode = S60->screenDevice()->DisplayMode();
     S60->screenDepth = TDisplayModeUtils::NumDisplayModeBitsPerPixel(mode);
 
+    //NB: RWsSession::GetColorModeList tells you what window modes are supported,
+    //not what bitmap formats.
+    if(QSysInfo::symbianVersion() == QSysInfo::SV_9_2)
+        S60->supportsPremultipliedAlpha = 0;
+    else
+        S60->supportsPremultipliedAlpha = 1;
+
     RProcess me;
     TSecureId securId = me.SecureId();
     S60->uid = securId.operator TUid();
diff --git a/src/gui/kernel/qt_s60_p.h b/src/gui/kernel/qt_s60_p.h
index d33791b..e25bc81 100644
--- a/src/gui/kernel/qt_s60_p.h
+++ b/src/gui/kernel/qt_s60_p.h
@@ -81,6 +81,9 @@ QT_BEGIN_NAMESPACE
 // system events seems to start with 0x10
 const TInt KInternalStatusPaneChange = 0x50000000;
 
+//this macro exists because EColor16MAP enum value doesn't exist in Symbian OS 9.2
+#define Q_SYMBIAN_ECOLOR16MAP TDisplayMode(13)
+
 class QS60Data
 {
 public:
@@ -108,6 +111,7 @@ public:
     int mouseInteractionEnabled : 1;
     int virtualMouseRequired : 1;
     int qtOwnsS60Environment : 1;
+    int supportsPremultipliedAlpha : 1;
     QApplication::QS60MainApplicationFactory s60ApplicationFactory; // typedef'ed pointer type
     static inline void updateScreenSize();
 	static inline RWsSession& wsSession();
@@ -199,7 +203,7 @@ inline void QS60Data::updateScreenSize()
     S60->screenHeightInPixels = params.iPixelSize.iHeight;
     S60->screenWidthInTwips = params.iTwipsSize.iWidth;
     S60->screenHeightInTwips = params.iTwipsSize.iHeight;
-    
+
     S60->virtualMouseMaxAccel = qMax(S60->screenHeightInPixels, S60->screenWidthInPixels) / 20;
 
     TReal inches = S60->screenHeightInTwips / (TReal)KTwipsPerInch;
@@ -302,11 +306,9 @@ static inline QImage::Format qt_TDisplayMode2Format(TDisplayMode mode)
     case EColor16MA:
         format = QImage::Format_ARGB32;
         break;
-#if !defined(__SERIES60_31__) && !defined(__S60_32__)
-    case EColor16MAP:
+    case Q_SYMBIAN_ECOLOR16MAP:
         format = QImage::Format_ARGB32_Premultiplied;
         break;
-#endif
     default:
         format = QImage::Format_Invalid;
         break;
diff --git a/src/gui/styles/qs60style_s60.cpp b/src/gui/styles/qs60style_s60.cpp
index cde48d8..d760016 100644
--- a/src/gui/styles/qs60style_s60.cpp
+++ b/src/gui/styles/qs60style_s60.cpp
@@ -747,9 +747,8 @@ QPixmap QS60StyleModeSpecifics::createSkinnedGraphicsLX(QS60StylePrivate::SkinFr
     QPixmap result;
 
 //        QS60WindowSurface::unlockBitmapHeap();
-    static const bool canDoEColor16MAP = !(QSysInfo::s60Version() == QSysInfo::SV_S60_3_1 || QSysInfo::s60Version() == QSysInfo::SV_S60_3_2);
-    static const TDisplayMode displayMode = canDoEColor16MAP ? TDisplayMode(13) : EColor16MA; // 13 = EColor16MAP
-    static const TInt drawParam = canDoEColor16MAP ? KAknsDrawParamDefault : KAknsDrawParamNoClearUnderImage|KAknsDrawParamRGBOnly;
+    static const TDisplayMode displayMode = S60->supportsPremultipliedAlpha ? Q_SYMBIAN_ECOLOR16MAP : EColor16MA;
+    static const TInt drawParam = S60->supportsPremultipliedAlpha ? KAknsDrawParamDefault : KAknsDrawParamNoClearUnderImage|KAknsDrawParamRGBOnly;
 
     CFbsBitmap *frame = new (ELeave) CFbsBitmap(); //offscreen
     CleanupStack::PushL(frame);
@@ -776,7 +775,7 @@ QPixmap QS60StyleModeSpecifics::createSkinnedGraphicsLX(QS60StylePrivate::SkinFr
                            frameSkinID, centerSkinID,
                            drawParam );
 
-    if (canDoEColor16MAP) {
+    if (S60->supportsPremultipliedAlpha) {
         if (drawn)
             result = fromFbsBitmap(frame, NULL, flags, QImage::Format_ARGB32_Premultiplied);
     } else {
diff --git a/src/s60installs/eabi/QtGuiu.def b/src/s60installs/eabi/QtGuiu.def
index 7c3542e..97d6bee 100644
--- a/src/s60installs/eabi/QtGuiu.def
+++ b/src/s60installs/eabi/QtGuiu.def
@@ -2288,7 +2288,7 @@ EXPORTS
 	_ZN13QGestureEvent11setAcceptedEP8QGestureb @ 2287 NONAME
 	_ZN13QGestureEvent6acceptEP8QGesture @ 2288 NONAME
 	_ZN13QGestureEvent6ignoreEP8QGesture @ 2289 NONAME
-	_ZN13QGestureEvent7gestureEN2Qt11GestureTypeE @ 2290 NONAME
+	_ZN13QGestureEvent7gestureEN2Qt11GestureTypeE @ 2290 NONAME ABSENT ; MISSING:
 	_ZN13QGestureEventC1ERK5QListIP8QGestureE @ 2291 NONAME
 	_ZN13QGestureEventC2ERK5QListIP8QGestureE @ 2292 NONAME
 	_ZN13QGraphicsItem10addToIndexEv @ 2293 NONAME
@@ -2651,8 +2651,8 @@ EXPORTS
 	_ZN13QSwipeGesture13setSwipeAngleEf @ 2650 NONAME
 	_ZN13QSwipeGesture16staticMetaObjectE @ 2651 NONAME DATA 16
 	_ZN13QSwipeGesture19getStaticMetaObjectEv @ 2652 NONAME
-	_ZN13QSwipeGesture20setVerticalDirectionENS_14SwipeDirectionE @ 2653 NONAME
-	_ZN13QSwipeGesture22setHorizontalDirectionENS_14SwipeDirectionE @ 2654 NONAME
+	_ZN13QSwipeGesture20setVerticalDirectionENS_14SwipeDirectionE @ 2653 NONAME ABSENT ; MISSING:
+	_ZN13QSwipeGesture22setHorizontalDirectionENS_14SwipeDirectionE @ 2654 NONAME ABSENT ; MISSING:
 	_ZN13QSwipeGestureC1EP7QObject @ 2655 NONAME
 	_ZN13QSwipeGestureC2EP7QObject @ 2656 NONAME
 	_ZN13QTextDocument10adjustSizeEv @ 2657 NONAME
@@ -6369,12 +6369,12 @@ EXPORTS
 	_ZN8QGesture15setTargetObjectEP7QObject @ 6368 NONAME
 	_ZN8QGesture16staticMetaObjectE @ 6369 NONAME DATA 16
 	_ZN8QGesture19getStaticMetaObjectEv @ 6370 NONAME
-	_ZN8QGestureC1EN2Qt11GestureTypeEP7QObject @ 6371 NONAME
+	_ZN8QGestureC1EN2Qt11GestureTypeEP7QObject @ 6371 NONAME ABSENT ; MISSING:
 	_ZN8QGestureC1EP7QObject @ 6372 NONAME
-	_ZN8QGestureC1ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6373 NONAME
-	_ZN8QGestureC2EN2Qt11GestureTypeEP7QObject @ 6374 NONAME
+	_ZN8QGestureC1ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6373 NONAME ABSENT ; MISSING:
+	_ZN8QGestureC2EN2Qt11GestureTypeEP7QObject @ 6374 NONAME ABSENT ; MISSING:
 	_ZN8QGestureC2EP7QObject @ 6375 NONAME
-	_ZN8QGestureC2ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6376 NONAME
+	_ZN8QGestureC2ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6376 NONAME ABSENT ; MISSING:
 	_ZN8QGestureD0Ev @ 6377 NONAME
 	_ZN8QGestureD1Ev @ 6378 NONAME
 	_ZN8QGestureD2Ev @ 6379 NONAME
@@ -11557,4 +11557,29 @@ EXPORTS
 	qt_pixmap_cleanup_hook @ 11556 NONAME DATA 4
 	qt_pixmap_cleanup_hook_64 @ 11557 NONAME DATA 4
 	qt_tab_all_widgets @ 11558 NONAME DATA 1
+	_ZN18QGuiPlatformPlugin11qt_metacallEN11QMetaObject4CallEiPPv @ 11559 NONAME
+	_ZN18QGuiPlatformPlugin11qt_metacastEPKc @ 11560 NONAME
+	_ZN18QGuiPlatformPlugin12platformHintENS_12PlatformHintE @ 11561 NONAME
+	_ZN18QGuiPlatformPlugin14fileSystemIconERK9QFileInfo @ 11562 NONAME
+	_ZN18QGuiPlatformPlugin16staticMetaObjectE @ 11563 NONAME DATA 16
+	_ZN18QGuiPlatformPlugin19getStaticMetaObjectEv @ 11564 NONAME
+	_ZN18QGuiPlatformPlugin19systemIconThemeNameEv @ 11565 NONAME
+	_ZN18QGuiPlatformPlugin20iconThemeSearchPathsEv @ 11566 NONAME
+	_ZN18QGuiPlatformPlugin7paletteEv @ 11567 NONAME
+	_ZN18QGuiPlatformPlugin9styleNameEv @ 11568 NONAME
+	_ZN18QGuiPlatformPluginC1EP7QObject @ 11569 NONAME
+	_ZN18QGuiPlatformPluginC2EP7QObject @ 11570 NONAME
+	_ZN18QGuiPlatformPluginD0Ev @ 11571 NONAME
+	_ZN18QGuiPlatformPluginD1Ev @ 11572 NONAME
+	_ZN18QGuiPlatformPluginD2Ev @ 11573 NONAME
+	_ZN8QGestureC1ER15QGesturePrivateP7QObject @ 11574 NONAME
+	_ZN8QGestureC2ER15QGesturePrivateP7QObject @ 11575 NONAME
+	_ZNK13QGestureEvent7gestureEN2Qt11GestureTypeE @ 11576 NONAME
+	_ZNK18QGuiPlatformPlugin10metaObjectEv @ 11577 NONAME
+	_ZTI18QGuiPlatformPlugin @ 11578 NONAME
+	_ZTI27QGuiPlatformPluginInterface @ 11579 NONAME
+	_ZTV18QGuiPlatformPlugin @ 11580 NONAME
+	_ZThn8_N18QGuiPlatformPluginD0Ev @ 11581 NONAME
+	_ZThn8_N18QGuiPlatformPluginD1Ev @ 11582 NONAME
+	_Z22qt_paint_device_metricPK12QPaintDeviceNS_17PaintDeviceMetricE @ 11583 NONAME
 
diff --git a/src/s60installs/eabi/QtMultimediau.def b/src/s60installs/eabi/QtMultimediau.def
index 787ad3a..30f921c 100644
--- a/src/s60installs/eabi/QtMultimediau.def
+++ b/src/s60installs/eabi/QtMultimediau.def
@@ -115,8 +115,8 @@ EXPORTS
 	_ZN19QAbstractAudioInput6notifyEv @ 114 NONAME
 	_ZN19QVideoSurfaceFormat11setPropertyEPKcRK8QVariant @ 115 NONAME
 	_ZN19QVideoSurfaceFormat11setViewportERK5QRect @ 116 NONAME
-	_ZN19QVideoSurfaceFormat12setFrameRateERK5QPairIiiE @ 117 NONAME
-	_ZN19QVideoSurfaceFormat12setFrameRateEii @ 118 NONAME
+	_ZN19QVideoSurfaceFormat12setFrameRateERK5QPairIiiE @ 117 NONAME ABSENT
+	_ZN19QVideoSurfaceFormat12setFrameRateEii @ 118 NONAME ABSENT
 	_ZN19QVideoSurfaceFormat12setFrameSizeERK5QSizeNS_12ViewportModeE @ 119 NONAME
 	_ZN19QVideoSurfaceFormat12setFrameSizeEiiNS_12ViewportModeE @ 120 NONAME
 	_ZN19QVideoSurfaceFormat16setYuvColorSpaceENS_13YuvColorSpaceE @ 121 NONAME
@@ -275,4 +275,6 @@ EXPORTS
 	_ZThn8_N18QAudioEnginePluginD0Ev @ 274 NONAME
 	_ZThn8_N18QAudioEnginePluginD1Ev @ 275 NONAME
 	_Zls6QDebugRK19QVideoSurfaceFormat @ 276 NONAME
+	_ZTV28QAudioEngineFactoryInterface @ 277 NONAME ABSENT
+	_ZN19QVideoSurfaceFormat12setFrameRateEf @ 278 NONAME
 
diff --git a/src/s60installs/eabi/QtNetworku.def b/src/s60installs/eabi/QtNetworku.def
index f216f85..e561511 100644
--- a/src/s60installs/eabi/QtNetworku.def
+++ b/src/s60installs/eabi/QtNetworku.def
@@ -989,4 +989,6 @@ EXPORTS
 	_ZlsR11QDataStreamRK21QNetworkCacheMetaData @ 988 NONAME
 	_ZrsR11QDataStreamR12QHostAddress @ 989 NONAME
 	_ZrsR11QDataStreamR21QNetworkCacheMetaData @ 990 NONAME
+	_ZN15QNetworkRequest20setOriginatingObjectEP7QObject @ 991 NONAME
+	_ZNK15QNetworkRequest17originatingObjectEv @ 992 NONAME
 
diff --git a/src/s60installs/eabi/QtScriptu.def b/src/s60installs/eabi/QtScriptu.def
index d0a3e3e..1592664 100644
--- a/src/s60installs/eabi/QtScriptu.def
+++ b/src/s60installs/eabi/QtScriptu.def
@@ -341,4 +341,5 @@ EXPORTS
 	_ZThn8_N22QScriptExtensionPluginD1Ev @ 340 NONAME
 	_ZlsR11QDataStreamRK18QScriptContextInfo @ 341 NONAME
 	_ZrsR11QDataStreamR18QScriptContextInfo @ 342 NONAME
+	_Z5qHashRK13QScriptString @ 343 NONAME
 
diff --git a/src/s60installs/eabi/QtXmlu.def b/src/s60installs/eabi/QtXmlu.def
index d1ba69d..cc5115c 100644
--- a/src/s60installs/eabi/QtXmlu.def
+++ b/src/s60installs/eabi/QtXmlu.def
@@ -458,4 +458,3 @@ EXPORTS
 	_ZThn8_N18QXmlDefaultHandler18unparsedEntityDeclERK7QStringS2_S2_S2_ @ 457 NONAME
 	_ZThn8_NK18QXmlDefaultHandler11errorStringEv @ 458 NONAME
 	_ZlsR11QTextStreamRK8QDomNode @ 459 NONAME
-
diff --git a/src/s60installs/eabi/phononu.def b/src/s60installs/eabi/phononu.def
index 651a0b8..af1e3cc 100644
--- a/src/s60installs/eabi/phononu.def
+++ b/src/s60installs/eabi/phononu.def
@@ -534,4 +534,14 @@ EXPORTS
 	_ZThn8_N6Phonon19AbstractAudioOutputD1Ev @ 533 NONAME
 	_ZThn8_N6Phonon6EffectD0Ev @ 534 NONAME
 	_ZThn8_N6Phonon6EffectD1Ev @ 535 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE0EEE @ 536 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE1EEE @ 537 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE2EEE @ 538 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE3EEE @ 539 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE4EEE @ 540 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE0EEE @ 541 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE1EEE @ 542 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE2EEE @ 543 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE3EEE @ 544 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE4EEE @ 545 NONAME
 
diff --git a/tests/auto/qpixmap/tst_qpixmap.cpp b/tests/auto/qpixmap/tst_qpixmap.cpp
index 36c1518..9f5aee2 100644
--- a/tests/auto/qpixmap/tst_qpixmap.cpp
+++ b/tests/auto/qpixmap/tst_qpixmap.cpp
@@ -1144,7 +1144,7 @@ void tst_QPixmap::fromSymbianCFbsBitmap_data()
 //    QTest::newRow("EColor16MA small trans") << EColor16MA << smallWidth << smallHeight << QColor(255, 255, 0, 0);
 //    QTest::newRow("EColor16MA big trans") << EColor16MA << largeWidth << largeHeight << QColor(255, 255, 0, 0);
 
-#if !defined(__SERIES60_31__) && !defined(__S60_32__)
+#if !defined(__SERIES60_31__)
     QTest::newRow("EColor16MAP small") << EColor16MAP << smallWidth << smallHeight << QColor(Qt::red);
     QTest::newRow("EColor16MAP big") << EColor16MAP << largeWidth << largeHeight << QColor(Qt::red);
 #endif
-- 
cgit v0.12


From c238f7b7e299e742e71fdb043a7bc81bbfd6c419 Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Tue, 20 Oct 2009 14:47:42 +0300
Subject: Fixed QFileDialog crash on Symbian

softKeyActions QHash in QDialogButtonBoxPrivate was not kept properly
in sync with standardButtonHash, causing QFileDialog to crash upon
startup.

Reviewed-by: Sami Merila
---
 src/gui/widgets/qdialogbuttonbox.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/gui/widgets/qdialogbuttonbox.cpp b/src/gui/widgets/qdialogbuttonbox.cpp
index 10f8db8..2231b98 100644
--- a/src/gui/widgets/qdialogbuttonbox.cpp
+++ b/src/gui/widgets/qdialogbuttonbox.cpp
@@ -873,6 +873,11 @@ void QDialogButtonBox::setOrientation(Qt::Orientation orientation)
 void QDialogButtonBox::clear()
 {
     Q_D(QDialogButtonBox);
+#ifdef QT_SOFTKEYS_ENABLED
+    // Delete softkey actions as they have the buttons as parents
+    qDeleteAll(d->softKeyActions.values());
+    d->softKeyActions.clear();
+#endif
     // Remove the created standard buttons, they should be in the other lists, which will
     // do the deletion
     d->standardButtonHash.clear();
@@ -1025,6 +1030,11 @@ QPushButton *QDialogButtonBox::addButton(StandardButton button)
 void QDialogButtonBox::setStandardButtons(StandardButtons buttons)
 {
     Q_D(QDialogButtonBox);
+#ifdef QT_SOFTKEYS_ENABLED
+    // Delete softkey actions since they have the buttons as parents
+    qDeleteAll(d->softKeyActions.values());
+    d->softKeyActions.clear();
+#endif
     // Clear out all the old standard buttons, then recreate them.
     qDeleteAll(d->standardButtonHash.keys());
     d->standardButtonHash.clear();
-- 
cgit v0.12


From ce03601e522ab10381f375c7bfd8862938d6955a Mon Sep 17 00:00:00 2001
From: Richard Moe Gustavsen <richard.gustavsen@nokia.com>
Date: Tue, 20 Oct 2009 10:11:00 +0200
Subject: Mac: fix bug when reparenting non-native menu bars

If we reparent a naive menu bar inside a widget that
has a menu bar from before, the old menu bar is lost.
This patch makes sure that we don't set the new
menu bar in this case, but let it remain as-is in
case the widget is reparanted out again later.

Rev-By: MortenS
---
 src/gui/widgets/qmenu_mac.mm | 20 ++++++++++++++++++--
 src/gui/widgets/qmenubar.cpp |  9 +++++++--
 src/gui/widgets/qmenubar_p.h |  1 +
 3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/src/gui/widgets/qmenu_mac.mm b/src/gui/widgets/qmenu_mac.mm
index cee38ee..b238faf 100644
--- a/src/gui/widgets/qmenu_mac.mm
+++ b/src/gui/widgets/qmenu_mac.mm
@@ -1771,6 +1771,16 @@ QMenuBarPrivate::QMacMenuBarPrivate::removeAction(QMacMenuAction *action)
     actionItems.removeAll(action);
 }
 
+bool QMenuBarPrivate::macWidgetHasNativeMenubar(QWidget *widget)
+{
+    // This function is different from q->isNativeMenuBar(), as
+    // it returns true only if a native menu bar is actually
+    // _created_.
+    if (!widget)
+        return false;
+    return menubars()->contains(widget->window());
+}
+
 void
 QMenuBarPrivate::macCreateMenuBar(QWidget *parent)
 {
@@ -1778,16 +1788,22 @@ QMenuBarPrivate::macCreateMenuBar(QWidget *parent)
     static int dontUseNativeMenuBar = -1;
     // We call the isNativeMenuBar function here
     // because that will make sure that local overrides
-    // are dealt with correctly.
+    // are dealt with correctly. q->isNativeMenuBar() will, if not
+    // overridden, depend on the attribute Qt::AA_DontUseNativeMenuBar:
     bool qt_mac_no_native_menubar = !q->isNativeMenuBar();
     if (qt_mac_no_native_menubar == false && dontUseNativeMenuBar < 0) {
+        // The menubar is set to be native. Let's check (one time only
+        // for all menubars) if this is OK with the rest of the environment.
+        // As a result, Qt::AA_DontUseNativeMenuBar is set. NB: the application
+        // might still choose to not respect, or change, this flag.
         bool isPlugin = QApplication::testAttribute(Qt::AA_MacPluginApplication);
         bool environmentSaysNo = !qgetenv("QT_MAC_NO_NATIVE_MENUBAR").isEmpty();
         dontUseNativeMenuBar = isPlugin || environmentSaysNo;
         QApplication::instance()->setAttribute(Qt::AA_DontUseNativeMenuBar, dontUseNativeMenuBar);
         qt_mac_no_native_menubar = !q->isNativeMenuBar();
     }
-    if (!qt_mac_no_native_menubar) {
+    if (qt_mac_no_native_menubar == false) {
+        // INVARIANT: Use native menubar.
         extern void qt_event_request_menubarupdate(); //qapplication_mac.cpp
         qt_event_request_menubarupdate();
         if (!parent && !fallback) {
diff --git a/src/gui/widgets/qmenubar.cpp b/src/gui/widgets/qmenubar.cpp
index 13e7de4..f2f0722 100644
--- a/src/gui/widgets/qmenubar.cpp
+++ b/src/gui/widgets/qmenubar.cpp
@@ -1370,8 +1370,13 @@ void QMenuBarPrivate::handleReparent()
     oldWindow = newWindow;
 
 #ifdef Q_WS_MAC
-    macDestroyMenuBar();
-    macCreateMenuBar(newParent);
+    if (q->isNativeMenuBar() && !macWidgetHasNativeMenubar(newParent)) {
+        // If the new parent got a native menubar from before, keep that
+        // menubar rather than replace it with this one (because a parents
+        // menubar has precedence over children menubars).
+        macDestroyMenuBar();
+        macCreateMenuBar(newParent);
+    }
 #endif
 
 #ifdef Q_WS_WINCE
diff --git a/src/gui/widgets/qmenubar_p.h b/src/gui/widgets/qmenubar_p.h
index 0b27b97..7815969 100644
--- a/src/gui/widgets/qmenubar_p.h
+++ b/src/gui/widgets/qmenubar_p.h
@@ -196,6 +196,7 @@ public:
             return 0;
         }
     } *mac_menubar;
+    bool macWidgetHasNativeMenubar(QWidget *widget);
     void macCreateMenuBar(QWidget *);
     void macDestroyMenuBar();
     OSMenuRef macMenu();
-- 
cgit v0.12


From 3aa8e4defdf104aeb0101815decfebe9e7ebc660 Mon Sep 17 00:00:00 2001
From: ninerider <qt-info@nokia.com>
Date: Tue, 20 Oct 2009 14:31:30 +0200
Subject: Test fixes for Windows Mobile.

Accounting for double resolution devices on Windows Mobile in the test
data sets (tst_qgraphicsview_2.cpp).
Skipped a test involving mouse tracking (tst_qgraphicsview.cpp).

Reviewed-by: Joerg
---
 tests/auto/qgraphicsview/tst_qgraphicsview.cpp   |   4 +
 tests/auto/qgraphicsview/tst_qgraphicsview_2.cpp | 212 +++++++++++++----------
 2 files changed, 120 insertions(+), 96 deletions(-)

diff --git a/tests/auto/qgraphicsview/tst_qgraphicsview.cpp b/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
index 389200b..dc08d0e 100644
--- a/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
+++ b/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
@@ -3664,6 +3664,10 @@ void tst_QGraphicsView::task253415_reconnectUpdateSceneOnSceneChanged()
 
 void tst_QGraphicsView::task255529_transformationAnchorMouseAndViewportMargins()
 {
+#if defined(Q_OS_WINCE)
+    QSKIP("Qt/CE does not implement mouse tracking at this point", SkipAll);
+#endif
+
     QGraphicsScene scene(-100, -100, 200, 200);
     scene.addRect(QRectF(-50, -50, 100, 100), QPen(Qt::black), QBrush(Qt::blue));
 
diff --git a/tests/auto/qgraphicsview/tst_qgraphicsview_2.cpp b/tests/auto/qgraphicsview/tst_qgraphicsview_2.cpp
index 9567f9e..1bfaf51 100644
--- a/tests/auto/qgraphicsview/tst_qgraphicsview_2.cpp
+++ b/tests/auto/qgraphicsview/tst_qgraphicsview_2.cpp
@@ -43,6 +43,20 @@
 #include <QRectF>
 #include <QTransform>
 
+#ifdef Q_OS_WINCE
+#include <qguifunctions_wince.h>
+
+bool qt_wince_is_high_dpi() {
+    HDC deviceContext = GetDC(0);
+    int dpi = GetDeviceCaps(deviceContext, LOGPIXELSX);
+    ReleaseDC(0, deviceContext);
+    if ((dpi < 1000) && (dpi > 0))
+        return dpi > 96;
+    else
+        return false;
+}
+#endif
+
 Q_DECLARE_METATYPE(QList<int>)
 Q_DECLARE_METATYPE(QList<QRectF>)
 Q_DECLARE_METATYPE(QMatrix)
@@ -51,7 +65,7 @@ Q_DECLARE_METATYPE(QPointF)
 Q_DECLARE_METATYPE(QRectF)
 Q_DECLARE_METATYPE(Qt::ScrollBarPolicy)
 
-static void _scrollBarRanges_data_1()
+static void _scrollBarRanges_data_1(int offset)
 {    
     // No motif, flat frame
     QTest::newRow("1") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
@@ -59,73 +73,73 @@ static void _scrollBarRanges_data_1()
                        << 0 << 0 << 0 << 0 << false << false;
     QTest::newRow("2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << 0 << (50 + 16) << 0 << 16 << false << false;
+                       << 0 << (50 + offset) << 0 << offset  << false << false;
     QTest::newRow("3") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << 0 << (50 + 16) << 0 << (100 + 16) << false << false;
+                       << 0 << (50 + offset) << 0 << (100 + offset) << false << false;
     QTest::newRow("4") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
                        << 0 << 0 << 0 << 0 << false << false;
     QTest::newRow("5") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << -100 << (16-50) << -100 << (-100 + 16) << false << false;
+                       << -100 << (offset -50) << -100 << (-100 + offset) << false << false;
     QTest::newRow("6") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << -100 << (16-50) << -100 << 16 << false << false;
+                       << -100 << (offset -50) << -100 << offset << false << false;
     QTest::newRow("7") << QSize(150, 100) << QRectF(0, 0, 151, 101) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << 0 << 17 << 0 << 17 << false << false;
+                       << 0 << (offset + 1)  << 0 << offset + 1 << false << false;
     QTest::newRow("8") << QSize(150, 100) << QRectF(0, 0, 201, 101) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << 0 << (50 + 17) << 0 << 17 << false << false;
+                       << 0 << (50 + offset + 1) << 0 << offset + 1 << false << false;
     QTest::newRow("9") << QSize(150, 100) << QRectF(0, 0, 201, 201) << QTransform()
                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                       << 0 << (50 + 17) << 0 << (100 + 17) << false << false;
+                       << 0 << (50 + offset + 1) << 0 << (100 + offset + 1) << false << false;
     QTest::newRow("10") << QSize(150, 100) << QRectF(-101, -101, 151, 101) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << -101 << (-100 + 16) << -101 << (-100 + 16) << false << false;
+                        << -101 << (-100 + offset) << -101 << (-100 + offset) << false << false;
     QTest::newRow("11") << QSize(150, 100) << QRectF(-101, -101, 201, 101) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << (-101) << (16-50) << -101 << (-100 + 16) << false << false;
+                        << (-101) << (offset + -50) << -101 << (-100 + offset) << false << false;
     QTest::newRow("12") << QSize(150, 100) << QRectF(-101, -101, 201, 201) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << (-101) << (16-50) << (-101) << 16 << false << false;
+                        << (-101) << (offset -50) << (-101) << offset << false << false;
     QTest::newRow("13") << QSize(150, 100) << QRectF(0, 0, 166, 116) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << 0 << (16 + 16) << 0 << (16 + 16) << false << false;
+                        << 0 << (offset + 16) << 0 << (offset + 16) << false << false;
     QTest::newRow("14") << QSize(150, 100) << QRectF(0, 0, 216, 116) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << 0 << (50 + 16 + 16) << 0 << (16 + 16) << false << false;
+                        << 0 << (50 + offset + 16) << 0 << (offset + 16) << false << false;
     QTest::newRow("15") << QSize(150, 100) << QRectF(0, 0, 216, 216) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << 0 << (50 + 16 + 16) << 0 << (100 + 16 + 16) << false << false;
+                        << 0 << (50 + offset + 16) << 0 << (100 + offset + 16) << false << false;
     QTest::newRow("16") << QSize(150, 100) << QRectF(-116, -116, 166, 116) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << (-100 - 16) << (-100 + 16) << (-100 - 16) << (-100 + 16) << false << false;
+                        << (-100 - 16) << (-100 + offset) << (-100 - 16 ) << (-100 + offset) << false << false;
     QTest::newRow("17") << QSize(150, 100) << QRectF(-116, -116, 216, 116) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << (-100 - 16) << (16-50) << (-100 - 16) << (-100 + 16) << false << false;
+                        << (-100 - 16) << (offset -50) << (-100 - 16) << (-100 + offset) << false << false;
     QTest::newRow("18") << QSize(150, 100) << QRectF(-116, -116, 216, 216) << QTransform()
                         << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                        << (-100 - 16) << (16-50) << (-100 - 16) << 16 << false << false;
+                        << (-100 - 16) << (offset -50) << (-100 - 16) << offset << false << false;
     QTest::newRow("1 x2") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << 0 << (150 + 16) << 0 << (100 + 16) << false << false;
+                          << 0 << (150 + offset) << 0 << (100 + offset) << false << false;
     QTest::newRow("2 x2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << 0 << (250 + 16) << 0 << (100 + 16) << false << false;
+                          << 0 << (250 + offset) << 0 << (100 + offset) << false << false;
     QTest::newRow("3 x2") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << 0 << (250 + 16) << 0 << (300 + 16) << false << false;
+                          << 0 << (250 + offset) << 0 << (300 + offset) << false << false;
     QTest::newRow("4 x2") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << -200 << (-50 + 16) << -200 << (-100 + 16) << false << false;
+                          << -200 << (-50 + offset) << -200 << (-100 + offset) << false << false;
     QTest::newRow("5 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << -200 << (50 + 16) << -200 << (-100 + 16) << false << false;
+                          << -200 << (50 + offset) << -200 << (-100 + offset) << false << false;
     QTest::newRow("6 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform().scale(2, 2)
                           << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                          << -200 << (50 + 16) << -200 << (100 + 16) << false << false;
+                          << -200 << (50 + offset) << -200 << (100 + offset) << false << false;
     QTest::newRow("1 No ScrollBars") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
                                      << Qt::ScrollBarAlwaysOff << Qt::ScrollBarAlwaysOff
                                      << 0 << 0 << 0 << 0 << false << false;
@@ -272,7 +286,7 @@ static void _scrollBarRanges_data_1()
                                             << -200 << (50 + 16) << -200 << (100 + 16) << false << false;
 }
 
-static void _scrollBarRanges_data_2()
+static void _scrollBarRanges_data_2(int offset)
 {
     // Motif, flat frame
     QTest::newRow("Motif, 1") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
@@ -280,73 +294,73 @@ static void _scrollBarRanges_data_2()
                               << 0 << 0 << 0 << 0 << true << false;
     QTest::newRow("Motif, 2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << 0 << (50 + 16) << 0 << 16 << true << false;
+                              << 0 << (50 + offset) << 0 << offset << true << false;
     QTest::newRow("Motif, 3") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << 0 << (50 + 16) << 0 << (100 + 16) << true << false;
+                              << 0 << (50 + offset) << 0 << (100 + offset) << true << false;
     QTest::newRow("Motif, 4") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
                               << 0 << 0 << 0 << 0 << true << false;
     QTest::newRow("Motif, 5") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << -100 << (16-50) << -100 << (-100 + 16) << true << false;
+                              << -100 << (offset-50) << -100 << (-100 + offset) << true << false;
     QTest::newRow("Motif, 6") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << -100 << (16-50) << -100 << 16 << true << false;
+                              << -100 << (offset-50) << -100 << offset << true << false;
     QTest::newRow("Motif, 7") << QSize(150, 100) << QRectF(0, 0, 151, 101) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << 0 << 17 << 0 << 17 << true << false;
+                              << 0 << offset + 1 << 0 << offset + 1 << true << false;
     QTest::newRow("Motif, 8") << QSize(150, 100) << QRectF(0, 0, 201, 101) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << 0 << (50 + 17) << 0 << 17 << true << false;
+                              << 0 << (50 + offset + 1) << 0 << offset + 1 << true << false;
     QTest::newRow("Motif, 9") << QSize(150, 100) << QRectF(0, 0, 201, 201) << QTransform()
                               << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                              << 0 << (50 + 17) << 0 << (100 + 17) << true << false;
+                              << 0 << (50 + offset + 1) << 0 << (100 + offset + 1) << true << false;
     QTest::newRow("Motif, 10") << QSize(150, 100) << QRectF(-101, -101, 151, 101) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << -101 << (-100 + 16) << -101 << (-100 + 16) << true << false;
+                               << -101 << (-100 + offset) << -101 << (-100 + offset) << true << false;
     QTest::newRow("Motif, 11") << QSize(150, 100) << QRectF(-101, -101, 201, 101) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << (-101) << (16-50) << -101 << (-100 + 16) << true << false;
+                               << (-101) << (offset-50) << -101 << (-100 + offset) << true << false;
     QTest::newRow("Motif, 12") << QSize(150, 100) << QRectF(-101, -101, 201, 201) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << (-101) << (16-50) << (-101) << 16 << true << false;
+                               << (-101) << (offset-50) << (-101) << offset << true << false;
     QTest::newRow("Motif, 13") << QSize(150, 100) << QRectF(0, 0, 166, 116) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (16 + 16) << 0 << (16 + 16) << true << false;
+                               << 0 << (offset + 16) << 0 << (offset + 16) << true << false;
     QTest::newRow("Motif, 14") << QSize(150, 100) << QRectF(0, 0, 216, 116) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 16 + 16) << 0 << (16 + 16) << true << false;
+                               << 0 << (50 + offset + 16) << 0 << (offset + 16) << true << false;
     QTest::newRow("Motif, 15") << QSize(150, 100) << QRectF(0, 0, 216, 216) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 16 + 16) << 0 << (100 + 16 + 16) << true << false;
+                               << 0 << (50 + offset + 16) << 0 << (100 + offset + 16) << true << false;
     QTest::newRow("Motif, 16") << QSize(150, 100) << QRectF(-116, -116, 166, 116) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << (-100 - 16) << (-100 + 16) << (-100 - 16) << (-100 + 16) << true << false;
+                               << (-100 - 16) << (-100 + offset) << (-100 - 16) << (-100 + offset) << true << false;
     QTest::newRow("Motif, 17") << QSize(150, 100) << QRectF(-116, -116, 216, 116) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << (-100 - 16) << (16-50) << (-100 - 16) << (-100 + 16) << true << false;
+                               << (-100 - 16) << (offset-50) << (-100 - 16) << (-100 + offset) << true << false;
     QTest::newRow("Motif, 18") << QSize(150, 100) << QRectF(-116, -116, 216, 216) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << (-100 - 16) << (16-50) << (-100 - 16) << 16 << true << false;
+                               << (-100 - 16) << (offset-50) << (-100 - 16) << offset << true << false;
     QTest::newRow("Motif, 1 x2") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << 0 << (150 + 16) << 0 << (100 + 16) << true << false;
+                                 << 0 << (150 + offset) << 0 << (100 + offset) << true << false;
     QTest::newRow("Motif, 2 x2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << 0 << (250 + 16) << 0 << (100 + 16) << true << false;
+                                 << 0 << (250 + offset) << 0 << (100 + offset) << true << false;
     QTest::newRow("Motif, 3 x2") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << 0 << (250 + 16) << 0 << (300 + 16) << true << false;
+                                 << 0 << (250 + offset) << 0 << (300 + offset) << true << false;
     QTest::newRow("Motif, 4 x2") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << -200 << (-50 + 16) << -200 << (-100 + 16) << true << false;
+                                 << -200 << (-50 + offset) << -200 << (-100 + offset) << true << false;
     QTest::newRow("Motif, 5 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << -200 << (50 + 16) << -200 << (-100 + 16) << true << false;
+                                 << -200 << (50 + offset) << -200 << (-100 + offset) << true << false;
     QTest::newRow("Motif, 6 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform().scale(2, 2)
                                  << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                 << -200 << (50 + 16) << -200 << (100 + 16) << true << false;
+                                 << -200 << (50 + offset) << -200 << (100 + offset) << true << false;
     QTest::newRow("Motif, 1 No ScrollBars") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
                                             << Qt::ScrollBarAlwaysOff << Qt::ScrollBarAlwaysOff
                                             << 0 << 0 << 0 << 0 << true << false;
@@ -493,7 +507,7 @@ static void _scrollBarRanges_data_2()
                                                    << -200 << (50 + 16) << -200 << (100 + 16) << true << false;
 }
 
-static void _scrollBarRanges_data_3()
+static void _scrollBarRanges_data_3(int offset)
 {
     // No motif, styled panel
     QTest::newRow("Styled, 1") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
@@ -501,73 +515,73 @@ static void _scrollBarRanges_data_3()
                                << 0 << 0 << 0 << 0 << false << true;
     QTest::newRow("Styled, 2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 16) << 0 << 16 << false << true;
+                               << 0 << (50 + offset) << 0 << offset << false << true;
     QTest::newRow("Styled, 3") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 16) << 0 << (100 + 16) << false << true;
+                               << 0 << (50 + offset) << 0 << (100 + offset) << false << true;
     QTest::newRow("Styled, 4") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
                                << 0 << 0 << 0 << 0 << false << true;
     QTest::newRow("Styled, 5") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << -100 << (16-50) << -100 << (-100 + 16) << false << true;
+                               << -100 << (offset-50) << -100 << (-100 + offset) << false << true;
     QTest::newRow("Styled, 6") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << -100 << (16-50) << -100 << 16 << false << true;
+                               << -100 << (offset-50) << -100 << offset << false << true;
     QTest::newRow("Styled, 7") << QSize(150, 100) << QRectF(0, 0, 151, 101) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << 17 << 0 << 17 << false << true;
+                               << 0 << offset + 1 << 0 << offset + 1 << false << true;
     QTest::newRow("Styled, 8") << QSize(150, 100) << QRectF(0, 0, 201, 101) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 17) << 0 << 17 << false << true;
+                               << 0 << (50 + offset + 1) << 0 << offset + 1 << false << true;
     QTest::newRow("Styled, 9") << QSize(150, 100) << QRectF(0, 0, 201, 201) << QTransform()
                                << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                               << 0 << (50 + 17) << 0 << (100 + 17) << false << true;
+                               << 0 << (50 + offset + 1) << 0 << (100 + offset + 1) << false << true;
     QTest::newRow("Styled, 10") << QSize(150, 100) << QRectF(-101, -101, 151, 101) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << -101 << (-100 + 16) << -101 << (-100 + 16) << false << true;
+                                << -101 << (-100 + offset) << -101 << (-100 + offset) << false << true;
     QTest::newRow("Styled, 11") << QSize(150, 100) << QRectF(-101, -101, 201, 101) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << (-101) << (16-50) << -101 << (-100 + 16) << false << true;
+                                << (-101) << (offset-50) << -101 << (-100 + offset) << false << true;
     QTest::newRow("Styled, 12") << QSize(150, 100) << QRectF(-101, -101, 201, 201) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << (-101) << (16-50) << (-101) << 16 << false << true;
+                                << (-101) << (offset-50) << (-101) << offset << false << true;
     QTest::newRow("Styled, 13") << QSize(150, 100) << QRectF(0, 0, 166, 116) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << 0 << (16 + 16) << 0 << (16 + 16) << false << true;
+                                << 0 << (offset + 16) << 0 << (offset + 16) << false << true;
     QTest::newRow("Styled, 14") << QSize(150, 100) << QRectF(0, 0, 216, 116) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << 0 << (50 + 16 + 16) << 0 << (16 + 16) << false << true;
+                                << 0 << (50 + offset + 16) << 0 << (offset + 16) << false << true;
     QTest::newRow("Styled, 15") << QSize(150, 100) << QRectF(0, 0, 216, 216) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << 0 << (50 + 16 + 16) << 0 << (100 + 16 + 16) << false << true;
+                                << 0 << (50 + offset + 16) << 0 << (100 + offset + 16) << false << true;
     QTest::newRow("Styled, 16") << QSize(150, 100) << QRectF(-116, -116, 166, 116) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << (-100 - 16) << (-100 + 16) << (-100 - 16) << (-100 + 16) << false << true;
+                                << (-100 - 16) << (-100 + offset) << (-100 - 16) << (-100 + offset) << false << true;
     QTest::newRow("Styled, 17") << QSize(150, 100) << QRectF(-116, -116, 216, 116) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << (-100 - 16) << (16-50) << (-100 - 16) << (-100 + 16) << false << true;
+                                << (-100 - 16) << (offset-50) << (-100 - 16) << (-100 + offset) << false << true;
     QTest::newRow("Styled, 18") << QSize(150, 100) << QRectF(-116, -116, 216, 216) << QTransform()
                                 << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                << (-100 - 16) << (16-50) << (-100 - 16) << 16 << false << true;
+                                << (-100 - 16) << (offset-50) << (-100 - 16) << offset << false << true;
     QTest::newRow("Styled, 1 x2") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << 0 << (150 + 16) << 0 << (100 + 16) << false << true;
+                                  << 0 << (150 + offset) << 0 << (100 + offset) << false << true;
     QTest::newRow("Styled, 2 x2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << 0 << (250 + 16) << 0 << (100 + 16) << false << true;
+                                  << 0 << (250 + offset) << 0 << (100 + offset) << false << true;
     QTest::newRow("Styled, 3 x2") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << 0 << (250 + 16) << 0 << (300 + 16) << false << true;
+                                  << 0 << (250 + offset) << 0 << (300 + offset) << false << true;
     QTest::newRow("Styled, 4 x2") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << -200 << (-50 + 16) << -200 << (-100 + 16) << false << true;
+                                  << -200 << (-50 + offset) << -200 << (-100 + offset) << false << true;
     QTest::newRow("Styled, 5 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << -200 << (50 + 16) << -200 << (-100 + 16) << false << true;
+                                  << -200 << (50 + offset) << -200 << (-100 + offset) << false << true;
     QTest::newRow("Styled, 6 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform().scale(2, 2)
                                   << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                  << -200 << (50 + 16) << -200 << (100 + 16) << false << true;
+                                  << -200 << (50 + offset) << -200 << (100 + offset) << false << true;
     QTest::newRow("Styled, 1 No ScrollBars") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
                                              << Qt::ScrollBarAlwaysOff << Qt::ScrollBarAlwaysOff
                                              << 0 << 0 << 0 << 0 << false << true;
@@ -714,7 +728,7 @@ static void _scrollBarRanges_data_3()
                                                     << -200 << (50 + 16) << -200 << (100 + 16) << false << true;
 }
 
-static void _scrollBarRanges_data_4()
+static void _scrollBarRanges_data_4(int offset)
 {
     // Motif, styled panel
     QTest::newRow("Motif, Styled, 1") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
@@ -722,73 +736,73 @@ static void _scrollBarRanges_data_4()
                                       << 0 << 0 << 0 << 0 << true << true;
     QTest::newRow("Motif, Styled, 2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << 0 << (50 + 16 + 4) << 0 << (16 + 4) << true << true;
+                                      << 0 << (50 + offset + 4) << 0 << (offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 3") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << 0 << (50 + 16 + 4) << 0 << (100 + 16 + 4) << true << true;
+                                      << 0 << (50 + offset + 4) << 0 << (100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 4") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
                                       << 0 << 0 << 0 << 0 << true << true;
     QTest::newRow("Motif, Styled, 5") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << -100 << (16 + 4 - 50) << -100 << (-100 + 16 + 4) << true << true;
+                                      << -100 << (offset + 4 - 50) << -100 << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 6") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << -100 << (16 + 4 - 50) << -100 << (16 + 4) << true << true;
+                                      << -100 << (offset + 4 - 50) << -100 << (offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 7") << QSize(150, 100) << QRectF(0, 0, 151, 101) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << 0 << (17 + 4) << 0 << (17 + 4) << true << true;
+                                      << 0 << (offset + 1 + 4) << 0 << (offset + 1 + 4) << true << true;
     QTest::newRow("Motif, Styled, 8") << QSize(150, 100) << QRectF(0, 0, 201, 101) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << 0 << (50 + 17 + 4) << 0 << (17 + 4) << true << true;
+                                      << 0 << (50 + offset + 1 + 4) << 0 << (offset + 1 + 4) << true << true;
     QTest::newRow("Motif, Styled, 9") << QSize(150, 100) << QRectF(0, 0, 201, 201) << QTransform()
                                       << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                      << 0 << (50 + 17 + 4) << 0 << (100 + 17 + 4) << true << true;
+                                      << 0 << (50 + offset + 1 + 4) << 0 << (100 + offset + 1 + 4) << true << true;
     QTest::newRow("Motif, Styled, 10") << QSize(150, 100) << QRectF(-101, -101, 151, 101) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << -101 << (-100 + 16 + 4) << -101 << (-100 + 16 + 4) << true << true;
+                                       << -101 << (-100 + offset + 4) << -101 << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 11") << QSize(150, 100) << QRectF(-101, -101, 201, 101) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << (-101) << (16 + 4 - 50) << -101 << (-100 + 16 + 4) << true << true;
+                                       << (-101) << (offset + 4 - 50) << -101 << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 12") << QSize(150, 100) << QRectF(-101, -101, 201, 201) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << (-101) << (16 + 4 - 50) << (-101) << (16 + 4) << true << true;
+                                       << (-101) << (offset + 4 - 50) << (-101) << (offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 13") << QSize(150, 100) << QRectF(0, 0, 166, 116) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << 0 << (16 + 16 + 4) << 0 << (16 + 16 + 4) << true << true;
+                                       << 0 << (offset + 16 + 4) << 0 << (offset + 16 + 4) << true << true;
     QTest::newRow("Motif, Styled, 14") << QSize(150, 100) << QRectF(0, 0, 216, 116) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << 0 << (50 + 16 + 16 + 4) << 0 << (16 + 16 + 4) << true << true;
+                                       << 0 << (50 + offset + 16 + 4) << 0 << (offset + 16 + 4) << true << true;
     QTest::newRow("Motif, Styled, 15") << QSize(150, 100) << QRectF(0, 0, 216, 216) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << 0 << (50 + 16 + 16 + 4) << 0 << (100 + 16 + 16 + 4) << true << true;
+                                       << 0 << (50 + offset + 16 + 4) << 0 << (100 + offset + 16 + 4) << true << true;
     QTest::newRow("Motif, Styled, 16") << QSize(150, 100) << QRectF(-116, -116, 166, 116) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << (-100 - 16) << (-100 + 16 + 4) << (-100 - 16) << (-100 + 16 + 4) << true << true;
+                                       << (-100 - 16) << (-100 + offset + 4) << (-100 - 16) << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 17") << QSize(150, 100) << QRectF(-116, -116, 216, 116) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << (-100 - 16) << (16 + 4 - 50) << (-100 - 16) << (-100 + 16 + 4) << true << true;
+                                       << (-100 - 16) << (offset + 4 - 50) << (-100 - 16) << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 18") << QSize(150, 100) << QRectF(-116, -116, 216, 216) << QTransform()
                                        << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                       << (-100 - 16) << (16 + 4 - 50) << (-100 - 16) << (16 + 4) << true << true;
+                                       << (-100 - 16) << (offset + 4 - 50) << (-100 - 16) << (offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 1 x2") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << 0 << (150 + 16 + 4) << 0 << (100 + 16 + 4) << true << true;
+                                         << 0 << (150 + offset + 4) << 0 << (100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 2 x2") << QSize(150, 100) << QRectF(0, 0, 200, 100) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << 0 << (250 + 16 + 4) << 0 << (100 + 16 + 4) << true << true;
+                                         << 0 << (250 + offset + 4) << 0 << (100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 3 x2") << QSize(150, 100) << QRectF(0, 0, 200, 200) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << 0 << (250 + 16 + 4) << 0 << (300 + 16 + 4) << true << true;
+                                         << 0 << (250 + offset + 4) << 0 << (300 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 4 x2") << QSize(150, 100) << QRectF(-100, -100, 150, 100) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << -200 << (-50 + 16 + 4) << -200 << (-100 + 16 + 4) << true << true;
+                                         << -200 << (-50 + offset + 4) << -200 << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 5 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 100) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << -200 << (50 + 16 + 4) << -200 << (-100 + 16 + 4) << true << true;
+                                         << -200 << (50 + offset + 4) << -200 << (-100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 6 x2") << QSize(150, 100) << QRectF(-100, -100, 200, 200) << QTransform().scale(2, 2)
                                          << Qt::ScrollBarAsNeeded << Qt::ScrollBarAsNeeded
-                                         << -200 << (50 + 16 + 4) << -200 << (100 + 16 + 4) << true << true;
+                                         << -200 << (50 + offset + 4) << -200 << (100 + offset + 4) << true << true;
     QTest::newRow("Motif, Styled, 1 No ScrollBars") << QSize(150, 100) << QRectF(0, 0, 150, 100) << QTransform()
                                                     << Qt::ScrollBarAlwaysOff << Qt::ScrollBarAlwaysOff
                                                     << 0 << 0 << 0 << 0 << true << true;
@@ -949,8 +963,14 @@ void _scrollBarRanges_data()
     QTest::addColumn<bool>("useMotif");
     QTest::addColumn<bool>("useStyledPanel");
 
-    _scrollBarRanges_data_1();
-    _scrollBarRanges_data_2();
-    _scrollBarRanges_data_3();
-    _scrollBarRanges_data_4();
+    int offset = 16;
+#ifdef Q_OS_WINCE
+    if (qt_wince_is_high_dpi())
+        offset *= 2;
+#endif
+
+    _scrollBarRanges_data_1(offset);
+    _scrollBarRanges_data_2(offset);
+    _scrollBarRanges_data_3(offset);
+    _scrollBarRanges_data_4(offset);
 }
-- 
cgit v0.12


From 76ef766a32cdcfd9cd64cf1d288c92a2b2040c15 Mon Sep 17 00:00:00 2001
From: ninerider <qt-info@nokia.com>
Date: Tue, 20 Oct 2009 14:40:26 +0200
Subject: Windows CE gets a different paint event count than windows

Reviewed-by: Joerg
---
 tests/auto/qtabwidget/tst_qtabwidget.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/auto/qtabwidget/tst_qtabwidget.cpp b/tests/auto/qtabwidget/tst_qtabwidget.cpp
index 27c19df..1387a92 100644
--- a/tests/auto/qtabwidget/tst_qtabwidget.cpp
+++ b/tests/auto/qtabwidget/tst_qtabwidget.cpp
@@ -590,9 +590,11 @@ void tst_QTabWidget::paintEventCount()
 
     QTest::qWait(1000);
 
-    // Mac and Windows get multiple repaints on the first show, so use those as a starting point.
+    // Mac, Windows and Windows CE get multiple repaints on the first show, so use those as a starting point.
     static const int MaxInitialPaintCount =
-#if defined(Q_WS_WIN)
+#if defined(Q_OS_WINCE)
+        4;
+#elif defined(Q_WS_WIN)
         2;
 #elif defined(Q_WS_MAC)
         5;
-- 
cgit v0.12


From 58574ea3590fbb28da5be73b983d83f0a8824d00 Mon Sep 17 00:00:00 2001
From: Markus Goetz <Markus.Goetz@nokia.com>
Date: Tue, 20 Oct 2009 15:03:56 +0200
Subject: tst_qsslsocket: new bigChunk testcase

This new test is to find out if the BIO size of OpenSSL is limited
or not. The test passes on my Linux, however the OpenSSL docu suggests
that the BIO size is limited.
From http://www.openssl.org/docs/crypto/BIO_s_bio.html
"This is currently 17K".

Reviewed-by: Peter Hartmann
---
 tests/auto/qsslsocket/tst_qsslsocket.cpp | 45 ++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/tests/auto/qsslsocket/tst_qsslsocket.cpp b/tests/auto/qsslsocket/tst_qsslsocket.cpp
index 6b330e1..2f1c2e2 100644
--- a/tests/auto/qsslsocket/tst_qsslsocket.cpp
+++ b/tests/auto/qsslsocket/tst_qsslsocket.cpp
@@ -173,6 +173,7 @@ private slots:
     void disconnectFromHostWhenConnected();
     void resetProxy();
     void readFromClosedSocket();
+    void writeBigChunk();
 
     static void exitLoop()
     {
@@ -1537,6 +1538,50 @@ void tst_QSslSocket::readFromClosedSocket()
     QVERIFY(!socket->bytesToWrite());
 }
 
+void tst_QSslSocket::writeBigChunk()
+{
+    if (!QSslSocket::supportsSsl())
+        return;
+
+    QSslSocketPtr socket = newSocket();
+    this->socket = socket;
+
+    connect(socket, SIGNAL(sslErrors(const QList<QSslError> &)), this, SLOT(ignoreErrorSlot()));
+    socket->connectToHostEncrypted(QtNetworkSettings::serverName(), 443);
+
+    QByteArray data;
+    data.resize(1024*1024*10); // 10 MB
+    // init with garbage. needed so ssl cannot compress it in an efficient way.
+    for (int i = 0; i < data.size() / sizeof(int); i++) {
+        int r = qrand();
+        data.data()[i*sizeof(int)] = r;
+    }
+
+    QVERIFY(socket->waitForEncrypted(10000));
+    QString errorBefore = socket->errorString();
+
+    int ret = socket->write(data.constData(), data.size());
+    QVERIFY(data.size() == ret);
+
+    // spin the event loop once so QSslSocket::transmit() gets called
+    QCoreApplication::processEvents();
+    QString errorAfter = socket->errorString();
+
+    // no better way to do this right now since the error is the same as the default error.
+    if (socket->errorString().startsWith(QLatin1String("Unable to write data")))
+    {
+        qWarning() << socket->error() << socket->errorString();
+        QFAIL("Error while writing! Check if the OpenSSL BIO size is limited?!");
+    }
+    // also check the error string. If another error (than UnknownError) occured, it should be different than before
+    QVERIFY(errorBefore == errorAfter);
+ 
+    // check that everything has been written to OpenSSL
+    QVERIFY(socket->bytesToWrite() == 0);
+
+    socket->close();
+}
+
 #endif // QT_NO_OPENSSL
 
 QTEST_MAIN(tst_QSslSocket)
-- 
cgit v0.12


From 147c524e703d4727d03c5f2ea3f98ace25905b73 Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Tue, 20 Oct 2009 16:10:57 +0200
Subject: Fix bug introduced by cleanup commit.

Reviewed-by: Gareth Stockwell
---
 src/3rdparty/phonon/mmf/audiooutput.cpp | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/3rdparty/phonon/mmf/audiooutput.cpp b/src/3rdparty/phonon/mmf/audiooutput.cpp
index bb0e5bc..82af9f1 100644
--- a/src/3rdparty/phonon/mmf/audiooutput.cpp
+++ b/src/3rdparty/phonon/mmf/audiooutput.cpp
@@ -105,8 +105,6 @@ QHash<QByteArray, QVariant> MMF::AudioOutput::audioOutputDescription(int index)
     QHash<QByteArray, QVariant> retval;
 
     if (index == AudioOutputDeviceID) {
-        QHash<QByteArray, QVariant> retval;
-
         retval.insert("name", QCoreApplication::translate("Phonon::MMF", "Audio Output"));
         retval.insert("description", QCoreApplication::translate("Phonon::MMF", "The audio output device"));
         retval.insert("available", true);
-- 
cgit v0.12


From e47ea4694fb9228d111e31d8c590e6d5c16e7461 Mon Sep 17 00:00:00 2001
From: Martin Pejcoch <martin.pejcoch@nokia.com>
Date: Thu, 15 Oct 2009 16:07:02 +0200
Subject: Set OFN_PATHMUSTEXIT as a default parameter

This will result in a warning if the path entered doesn't exist,
which is the behavior of native applications.

Reviewed-by: Prasanth
---
 src/gui/dialogs/qfiledialog_win.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/dialogs/qfiledialog_win.cpp b/src/gui/dialogs/qfiledialog_win.cpp
index b59c28b..8089b43 100644
--- a/src/gui/dialogs/qfiledialog_win.cpp
+++ b/src/gui/dialogs/qfiledialog_win.cpp
@@ -251,10 +251,10 @@ static OPENFILENAME* qt_win_make_OFN(QWidget *parent,
     ofn->nMaxFile = maxLen;
     ofn->lpstrInitialDir = (wchar_t*)tInitDir.utf16();
     ofn->lpstrTitle = (wchar_t*)tTitle.utf16();
-    ofn->Flags = (OFN_NOCHANGEDIR | OFN_HIDEREADONLY | OFN_EXPLORER);
+    ofn->Flags = (OFN_NOCHANGEDIR | OFN_HIDEREADONLY | OFN_EXPLORER | OFN_PATHMUSTEXIST);
     if (mode == QFileDialog::ExistingFile ||
          mode == QFileDialog::ExistingFiles)
-        ofn->Flags |= (OFN_FILEMUSTEXIST | OFN_PATHMUSTEXIST);
+        ofn->Flags |= (OFN_FILEMUSTEXIST);
     if (mode == QFileDialog::ExistingFiles)
         ofn->Flags |= (OFN_ALLOWMULTISELECT);
     if (!(options & QFileDialog::DontConfirmOverwrite))
-- 
cgit v0.12


From 0bdb8aa64deef437b94f4998f4c2f6ed93a38489 Mon Sep 17 00:00:00 2001
From: ck <qt-info@nokia.com>
Date: Tue, 20 Oct 2009 17:42:18 +0200
Subject: Assistant: Fix syntax error.

The offending code is normally ifdef'ed out, so the bug did not manifest
itself before.
---
 tools/assistant/lib/qhelpsearchquerywidget.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/assistant/lib/qhelpsearchquerywidget.cpp b/tools/assistant/lib/qhelpsearchquerywidget.cpp
index 361e9ac..f2f40ec 100644
--- a/tools/assistant/lib/qhelpsearchquerywidget.cpp
+++ b/tools/assistant/lib/qhelpsearchquerywidget.cpp
@@ -289,7 +289,7 @@ private slots:
     {
         QList<QHelpSearchQuery> queryList;
 #if !defined(QT_CLUCENE_SUPPORT)
-        queryList.append(QHelSearchQuery(QHelpSearchQuery::DEFAULT,
+        queryList.append(QHelpSearchQuery(QHelpSearchQuery::DEFAULT,
                                           QStringList(defaultQuery->text())));
 
 #else
-- 
cgit v0.12


From 77f2319ab80be40268da689d5bc4726257ddd7ab Mon Sep 17 00:00:00 2001
From: Harald Fernengel <harald.fernengel@nokia.com>
Date: Tue, 20 Oct 2009 17:40:40 +0200
Subject: Implement QAccesibleValueInterface for QProgressBar

Patch has been tested thorougly in the accessibility-fixes branch
of the qt-maemo repository, thus no review
---
 src/plugins/accessible/widgets/main.cpp          |  4 +++-
 src/plugins/accessible/widgets/simplewidgets.cpp | 28 ++++++++++++++++++++++++
 src/plugins/accessible/widgets/simplewidgets.h   | 19 ++++++++++++++++
 3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/src/plugins/accessible/widgets/main.cpp b/src/plugins/accessible/widgets/main.cpp
index 667de88..9a9a778 100644
--- a/src/plugins/accessible/widgets/main.cpp
+++ b/src/plugins/accessible/widgets/main.cpp
@@ -234,8 +234,10 @@ QAccessibleInterface *AccessibleFactory::create(const QString &classname, QObjec
         iface = new QAccessibleDisplay(widget, Grouping);
     } else if (classname == QLatin1String("QStatusBar")) {
         iface = new QAccessibleWidgetEx(widget, StatusBar);
+#ifndef QT_NO_PROGRESSBAR
     } else if (classname == QLatin1String("QProgressBar")) {
-        iface = new QAccessibleDisplay(widget);
+        iface = new QAccessibleProgressBar(widget);
+#endif
     } else if (classname == QLatin1String("QToolBar")) {
         iface = new QAccessibleWidgetEx(widget, ToolBar, widget->windowTitle());
 #ifndef QT_NO_MENUBAR
diff --git a/src/plugins/accessible/widgets/simplewidgets.cpp b/src/plugins/accessible/widgets/simplewidgets.cpp
index 1aadd6c..89482bb 100644
--- a/src/plugins/accessible/widgets/simplewidgets.cpp
+++ b/src/plugins/accessible/widgets/simplewidgets.cpp
@@ -756,6 +756,34 @@ void QAccessibleLineEdit::scrollToSubstring(int startIndex, int endIndex)
 
 #endif // QT_NO_LINEEDIT
 
+#ifndef QT_NO_PROGRESSBAR
+QAccessibleProgressBar::QAccessibleProgressBar(QWidget *o)
+    : QAccessibleDisplay(o)
+{
+    Q_ASSERT(progressBar());
+}
+
+QVariant QAccessibleProgressBar::currentValue()
+{
+    return progressBar()->value();
+}
+
+QVariant QAccessibleProgressBar::maximumValue()
+{
+    return progressBar()->maximum();
+}
+
+QVariant QAccessibleProgressBar::minimumValue()
+{
+    return progressBar()->minimum();
+}
+
+QProgressBar *QAccessibleProgressBar::progressBar() const
+{
+    return qobject_cast<QProgressBar *>(object());
+}
+#endif
+
 #endif // QT_NO_ACCESSIBILITY
 
 QT_END_NAMESPACE
diff --git a/src/plugins/accessible/widgets/simplewidgets.h b/src/plugins/accessible/widgets/simplewidgets.h
index abe5bdc..8de35ef 100644
--- a/src/plugins/accessible/widgets/simplewidgets.h
+++ b/src/plugins/accessible/widgets/simplewidgets.h
@@ -52,6 +52,7 @@ QT_BEGIN_NAMESPACE
 class QAbstractButton;
 class QLineEdit;
 class QToolButton;
+class QProgressBar;
 
 class QAccessibleButton : public QAccessibleWidgetEx
 {
@@ -150,6 +151,24 @@ protected:
 };
 #endif // QT_NO_LINEEDIT
 
+#ifndef QT_NO_PROGRESSBAR
+class QAccessibleProgressBar : public QAccessibleDisplay, public QAccessibleValueInterface
+{
+    Q_ACCESSIBLE_OBJECT
+public:
+    explicit QAccessibleProgressBar(QWidget *o);
+
+    // QAccessibleValueInterface
+    QVariant currentValue();
+    QVariant maximumValue();
+    QVariant minimumValue();
+    inline void setCurrentValue(const QVariant &) {}
+
+protected:
+    QProgressBar *progressBar() const;
+};
+#endif
+
 #endif // QT_NO_ACCESSIBILITY
 
 QT_END_NAMESPACE
-- 
cgit v0.12


From 339b5b04a98ad3a5569180b0a1a000e82e985867 Mon Sep 17 00:00:00 2001
From: Harald Fernengel <harald.fernengel@nokia.com>
Date: Tue, 20 Oct 2009 17:45:48 +0200
Subject: Introduce the QAccessibleActionInterface

with a sample implementation for QAccessibleButton. Not implemented
for all widgets yet (API is preliminary).

Patch has been in the accessibility-fixes branch of qt-maemo for quite
a while now without complains, thus no reviewer.
---
 src/gui/accessible/qaccessible.h                 |  7 ++-
 src/gui/accessible/qaccessible2.cpp              | 12 +++++
 src/gui/accessible/qaccessible2.h                | 16 +++++++
 src/plugins/accessible/widgets/simplewidgets.cpp | 56 ++++++++++++++++++++++++
 src/plugins/accessible/widgets/simplewidgets.h   | 14 +++++-
 5 files changed, 103 insertions(+), 2 deletions(-)

diff --git a/src/gui/accessible/qaccessible.h b/src/gui/accessible/qaccessible.h
index 96fe91c..8f6d9d9 100644
--- a/src/gui/accessible/qaccessible.h
+++ b/src/gui/accessible/qaccessible.h
@@ -310,7 +310,8 @@ namespace QAccessible2
         TextInterface,
         EditableTextInterface,
         ValueInterface,
-        TableInterface
+        TableInterface,
+        ActionInterface
     };
 }
 
@@ -319,6 +320,7 @@ class QAccessibleTextInterface;
 class QAccessibleEditableTextInterface;
 class QAccessibleValueInterface;
 class QAccessibleTableInterface;
+class QAccessibleActionInterface;
 
 class Q_GUI_EXPORT QAccessibleInterface : public QAccessible
 {
@@ -376,6 +378,9 @@ public:
     inline QAccessibleTableInterface *tableInterface()
     { return reinterpret_cast<QAccessibleTableInterface *>(cast_helper(QAccessible2::TableInterface)); }
 
+    inline QAccessibleActionInterface *actionInterface()
+    { return reinterpret_cast<QAccessibleActionInterface *>(cast_helper(QAccessible2::ActionInterface)); }
+
 private:
     QAccessible2Interface *cast_helper(QAccessible2::InterfaceType);
 };
diff --git a/src/gui/accessible/qaccessible2.cpp b/src/gui/accessible/qaccessible2.cpp
index f731962..0867368 100644
--- a/src/gui/accessible/qaccessible2.cpp
+++ b/src/gui/accessible/qaccessible2.cpp
@@ -108,6 +108,18 @@ QT_BEGIN_NAMESPACE
     \link http://www.linux-foundation.org/en/Accessibility/IAccessible2 IAccessible2 Specification \endlink
 */
 
+/*!
+    \class QAccessibleActionInterface
+    \ingroup accessibility
+    \internal
+    \preliminary
+
+    \brief The QAccessibleActionInterface class implements support for
+    the IAccessibleAction interface.
+
+    \link http://www.linux-foundation.org/en/Accessibility/IAccessible2 IAccessible2 Specification \endlink
+*/
+
 QAccessibleSimpleEditableTextInterface::QAccessibleSimpleEditableTextInterface(
                 QAccessibleInterface *accessibleInterface)
     : iface(accessibleInterface)
diff --git a/src/gui/accessible/qaccessible2.h b/src/gui/accessible/qaccessible2.h
index 3281509..435c640 100644
--- a/src/gui/accessible/qaccessible2.h
+++ b/src/gui/accessible/qaccessible2.h
@@ -81,6 +81,7 @@ inline QAccessible2Interface *qAccessibleValueCastHelper() { return 0; }
 inline QAccessible2Interface *qAccessibleTextCastHelper() { return 0; }
 inline QAccessible2Interface *qAccessibleEditableTextCastHelper() { return 0; }
 inline QAccessible2Interface *qAccessibleTableCastHelper() { return 0; }
+inline QAccessible2Interface *qAccessibleActionCastHelper() { return 0; }
 
 #define Q_ACCESSIBLE_OBJECT \
     public: \
@@ -95,6 +96,8 @@ inline QAccessible2Interface *qAccessibleTableCastHelper() { return 0; }
             return qAccessibleValueCastHelper(); \
         case QAccessible2::TableInterface: \
             return qAccessibleTableCastHelper(); \
+        case QAccessible2::ActionInterface: \
+            return qAccessibleActionCastHelper(); \
         } \
         return 0; \
     } \
@@ -208,6 +211,19 @@ public:
                              int *columnSpan, bool *isSelected) = 0;
 };
 
+class Q_GUI_EXPORT QAccessibleActionInterface : public QAccessible2Interface
+{
+public:
+    inline QAccessible2Interface *qAccessibleActionCastHelper() { return this; }
+
+    virtual int actionCount() = 0;
+    virtual void doAction(int actionIndex) = 0;
+    virtual QString description(int actionIndex) = 0;
+    virtual QString name(int actionIndex) = 0;
+    virtual QString localizedName(int actionIndex) = 0;
+    virtual QStringList keyBindings(int actionIndex) = 0;
+};
+
 #endif // QT_NO_ACCESSIBILITY
 
 QT_END_NAMESPACE
diff --git a/src/plugins/accessible/widgets/simplewidgets.cpp b/src/plugins/accessible/widgets/simplewidgets.cpp
index 89482bb..aa51759 100644
--- a/src/plugins/accessible/widgets/simplewidgets.cpp
+++ b/src/plugins/accessible/widgets/simplewidgets.cpp
@@ -209,6 +209,62 @@ QAccessible::State QAccessibleButton::state(int child) const
     return state;
 }
 
+int QAccessibleButton::actionCount()
+{
+    return 1;
+}
+
+void QAccessibleButton::doAction(int actionIndex)
+{
+    switch (actionIndex) {
+    case 0:
+        button()->click();
+        break;
+    }
+}
+
+QString QAccessibleButton::description(int actionIndex)
+{
+    switch (actionIndex) {
+    case 0:
+        return QLatin1String("Clicks the button.");
+    default:
+        return QString();
+    }
+}
+
+QString QAccessibleButton::name(int actionIndex)
+{
+    switch (actionIndex) {
+    case 0:
+        return QLatin1String("Press");
+    default:
+        return QString();
+    }
+}
+
+QString QAccessibleButton::localizedName(int actionIndex)
+{
+    switch (actionIndex) {
+    case 0:
+        return tr("Press");
+    default:
+        return QString();
+    }
+}
+
+QStringList QAccessibleButton::keyBindings(int actionIndex)
+{
+    switch (actionIndex) {
+#ifdef QT_NO_SHORTCUT
+    case 0:
+        return button()->shortcut().toString();
+#endif
+    default:
+        return QStringList();
+    }
+}
+
 #ifndef QT_NO_TOOLBUTTON
 /*!
   \class QAccessibleToolButton
diff --git a/src/plugins/accessible/widgets/simplewidgets.h b/src/plugins/accessible/widgets/simplewidgets.h
index 8de35ef..0c1cf5e 100644
--- a/src/plugins/accessible/widgets/simplewidgets.h
+++ b/src/plugins/accessible/widgets/simplewidgets.h
@@ -42,6 +42,7 @@
 #ifndef SIMPLEWIDGETS_H
 #define SIMPLEWIDGETS_H
 
+#include <QtCore/qcoreapplication.h>
 #include <QtGui/qaccessible2.h>
 #include <QtGui/qaccessiblewidget.h>
 
@@ -54,8 +55,10 @@ class QLineEdit;
 class QToolButton;
 class QProgressBar;
 
-class QAccessibleButton : public QAccessibleWidgetEx
+class QAccessibleButton : public QAccessibleWidgetEx, public QAccessibleActionInterface
 {
+    Q_ACCESSIBLE_OBJECT
+    Q_DECLARE_TR_FUNCTIONS(QAccessibleButton)
 public:
     QAccessibleButton(QWidget *w, Role r);
 
@@ -65,6 +68,14 @@ public:
     QString actionText(int action, Text text, int child) const;
     bool doAction(int action, int child, const QVariantList &params);
 
+    // QAccessibleActionInterface
+    int actionCount();
+    void doAction(int actionIndex);
+    QString description(int actionIndex);
+    QString name(int actionIndex);
+    QString localizedName(int actionIndex);
+    QStringList keyBindings(int actionIndex);
+
 protected:
     QAbstractButton *button() const;
 };
@@ -102,6 +113,7 @@ protected:
 
 class QAccessibleDisplay : public QAccessibleWidgetEx
 {
+    Q_ACCESSIBLE_OBJECT
 public:
     explicit QAccessibleDisplay(QWidget *w, Role role = StaticText);
 
-- 
cgit v0.12


From 613866eb719e35fa2459cb12d46315ca9dcefa62 Mon Sep 17 00:00:00 2001
From: Liang QI <liang.qi@nokia.com>
Date: Tue, 20 Oct 2009 18:35:11 +0200
Subject: Fix tst_QHeaderView::length() on Symbian.

Just the default font size will not work for this case. We set it to smaller one. Notice: we should make sure view->length() is different between view->setStretchLastSection(true) and view->setStretchLastSection(false).

RevBy: Aleksandar Babic
---
 tests/auto/qheaderview/tst_qheaderview.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tests/auto/qheaderview/tst_qheaderview.cpp b/tests/auto/qheaderview/tst_qheaderview.cpp
index 3286768..c13e829 100644
--- a/tests/auto/qheaderview/tst_qheaderview.cpp
+++ b/tests/auto/qheaderview/tst_qheaderview.cpp
@@ -682,9 +682,12 @@ void tst_QHeaderView::visualIndexAt()
 
 void tst_QHeaderView::length()
 {
-#ifdef Q_OS_WINCE
+#if defined(Q_OS_WINCE)
     QFont font(QLatin1String("Tahoma"), 7);
     view->setFont(font);
+#elif defined(Q_OS_SYMBIAN)
+    QFont font(QLatin1String("Series 60 Sans"), 6);
+    view->setFont(font);
 #endif
     view->setStretchLastSection(true);
     view->show();
-- 
cgit v0.12


From 1315bcdd1e2add0ce26f0cb9a4d2a95477434315 Mon Sep 17 00:00:00 2001
From: Andy Shaw <qt-info@nokia.com>
Date: Tue, 20 Oct 2009 20:24:44 +0200
Subject: Ensure qmake does not lose the error code when going over the subdirs

When qmake was ran with -r over a subdirs project then it would lose the
error code if a later project succeeded.

This is a refix of the previous revert which has been confirmed to work
all over the place now.

Reviewed-by: Marius Storm-Olsen
---
 qmake/generators/metamakefile.cpp | 17 ++++++++++++-----
 qmake/generators/metamakefile.h   |  2 +-
 qmake/main.cpp                    |  6 +++++-
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/qmake/generators/metamakefile.cpp b/qmake/generators/metamakefile.cpp
index 5915fcf..819cdaf 100644
--- a/qmake/generators/metamakefile.cpp
+++ b/qmake/generators/metamakefile.cpp
@@ -291,6 +291,7 @@ SubdirsMetaMakefileGenerator::init()
     if(init_flag)
         return false;
     init_flag = true;
+    bool hasError = false;
 
     if(Option::recursive) {
         QString old_output_dir = Option::output_dir;
@@ -336,14 +337,18 @@ SubdirsMetaMakefileGenerator::init()
             }
             qmake_setpwd(sub->input_dir);
             Option::output_dir = sub->output_dir;
-            sub_proj->read(subdir.fileName());
+            bool tmpError = !sub_proj->read(subdir.fileName());
             if(!sub_proj->variables()["QMAKE_FAILED_REQUIREMENTS"].isEmpty()) {
                 fprintf(stderr, "Project file(%s) not recursed because all requirements not met:\n\t%s\n",
                         subdir.fileName().toLatin1().constData(),
                         sub_proj->values("QMAKE_FAILED_REQUIREMENTS").join(" ").toLatin1().constData());
                 delete sub;
                 delete sub_proj;
+                Option::output_dir = old_output_dir;
+                qmake_setpwd(oldpwd);
                 continue;
+            } else {
+                hasError |= tmpError;
             }
             sub->makefile = MetaMakefileGenerator::createMetaGenerator(sub_proj, sub_name);
             if(0 && sub->makefile->type() == SUBDIRSMETATYPE) {
@@ -351,7 +356,7 @@ SubdirsMetaMakefileGenerator::init()
             } else {
                 const QString output_name = Option::output.fileName();
                 Option::output.setFileName(sub->output_file);
-                sub->makefile->write(sub->output_dir);
+                hasError |= !sub->makefile->write(sub->output_dir);
                 delete sub;
                 qmakeClearCaches();
                 sub = 0;
@@ -376,7 +381,7 @@ SubdirsMetaMakefileGenerator::init()
     self->makefile->init();
     subs.append(self);
 
-    return true;
+    return !hasError;
 }
 
 bool
@@ -482,7 +487,7 @@ MetaMakefileGenerator::createMakefileGenerator(QMakeProject *proj, bool noIO)
 }
 
 MetaMakefileGenerator *
-MetaMakefileGenerator::createMetaGenerator(QMakeProject *proj, const QString &name, bool op)
+MetaMakefileGenerator::createMetaGenerator(QMakeProject *proj, const QString &name, bool op, bool *success)
 {
     MetaMakefileGenerator *ret = 0;
     if ((Option::qmake_mode == Option::QMAKE_GENERATE_MAKEFILE ||
@@ -492,7 +497,9 @@ MetaMakefileGenerator::createMetaGenerator(QMakeProject *proj, const QString &na
     }
     if (!ret)
         ret = new BuildsMetaMakefileGenerator(proj, name, op);
-    ret->init();
+    bool res = ret->init();
+    if (success)
+        *success = res;
     return ret;
 }
 
diff --git a/qmake/generators/metamakefile.h b/qmake/generators/metamakefile.h
index e69304a..f74f4a2 100644
--- a/qmake/generators/metamakefile.h
+++ b/qmake/generators/metamakefile.h
@@ -62,7 +62,7 @@ public:
 
     virtual ~MetaMakefileGenerator();
 
-    static MetaMakefileGenerator *createMetaGenerator(QMakeProject *proj, const QString &name, bool op=true);
+    static MetaMakefileGenerator *createMetaGenerator(QMakeProject *proj, const QString &name, bool op=true, bool *success = 0);
     static MakefileGenerator *createMakefileGenerator(QMakeProject *proj, bool noIO = false);
 
     inline QMakeProject *projectFile() const { return project; }
diff --git a/qmake/main.cpp b/qmake/main.cpp
index 73fdda9..a0346c5 100644
--- a/qmake/main.cpp
+++ b/qmake/main.cpp
@@ -168,7 +168,11 @@ int runQMake(int argc, char **argv)
                 continue;
         }
 
-        MetaMakefileGenerator *mkfile = MetaMakefileGenerator::createMetaGenerator(&project, QString(), false);
+        bool success = true;
+        MetaMakefileGenerator *mkfile = MetaMakefileGenerator::createMetaGenerator(&project, QString(), false, &success);
+        if (!success)
+            exit_val = 3;
+
         if(mkfile && !mkfile->write(oldpwd)) {
             if(Option::qmake_mode == Option::QMAKE_GENERATE_PROJECT)
                 fprintf(stderr, "Unable to generate project file.\n");
-- 
cgit v0.12


From 7997279bc22d30bf1d1a30a567bda33ecc9aeb2d Mon Sep 17 00:00:00 2001
From: Rhys Weatherley <rhys.weatherley@nokia.com>
Date: Wed, 21 Oct 2009 07:48:52 +1000
Subject: Increase PowerVR memory alignment from 8 to 32 for SGX systems.

Increasing the alignment does not seem to affect MBX.
---
 src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
index 17345a9..a9c22ef 100644
--- a/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
+++ b/src/plugins/gfxdrivers/powervr/QWSWSEGL/pvrqwsdrawable.c
@@ -662,7 +662,7 @@ int pvrQwsAllocBuffers(PvrQwsDrawable *drawable)
                 PVR2DMemFree(pvrQwsDisplay.context, drawable->backBuffers[index]);
         }
     }
-    drawable->stridePixels = (drawable->rect.width + 7) & ~7;
+    drawable->stridePixels = (drawable->rect.width + 31) & ~31;
     drawable->strideBytes =
         drawable->stridePixels *
         pvrQwsDisplay.screens[drawable->screen].bytesPerPixel;
-- 
cgit v0.12


From 9b6753eac7439caa2dd8915ed3616cef6d1f6cd0 Mon Sep 17 00:00:00 2001
From: Iain <qt-info@nokia.com>
Date: Wed, 21 Oct 2009 01:26:15 +0300
Subject: Update EABI DEF files for Symbian OS

Reviewed-by: TrustMe
---
 src/s60installs/eabi/QtGuiu.def        | 45 ++++++++++++++++++++++++++++------
 src/s60installs/eabi/QtMultimediau.def |  5 ++--
 src/s60installs/eabi/QtNetworku.def    |  4 +++
 src/s60installs/eabi/QtScriptu.def     |  1 +
 src/s60installs/eabi/phononu.def       | 10 ++++++++
 5 files changed, 55 insertions(+), 10 deletions(-)

diff --git a/src/s60installs/eabi/QtGuiu.def b/src/s60installs/eabi/QtGuiu.def
index 7c3542e..19afd9a 100644
--- a/src/s60installs/eabi/QtGuiu.def
+++ b/src/s60installs/eabi/QtGuiu.def
@@ -2288,7 +2288,7 @@ EXPORTS
 	_ZN13QGestureEvent11setAcceptedEP8QGestureb @ 2287 NONAME
 	_ZN13QGestureEvent6acceptEP8QGesture @ 2288 NONAME
 	_ZN13QGestureEvent6ignoreEP8QGesture @ 2289 NONAME
-	_ZN13QGestureEvent7gestureEN2Qt11GestureTypeE @ 2290 NONAME
+	_ZN13QGestureEvent7gestureEN2Qt11GestureTypeE @ 2290 NONAME ABSENT
 	_ZN13QGestureEventC1ERK5QListIP8QGestureE @ 2291 NONAME
 	_ZN13QGestureEventC2ERK5QListIP8QGestureE @ 2292 NONAME
 	_ZN13QGraphicsItem10addToIndexEv @ 2293 NONAME
@@ -2651,8 +2651,8 @@ EXPORTS
 	_ZN13QSwipeGesture13setSwipeAngleEf @ 2650 NONAME
 	_ZN13QSwipeGesture16staticMetaObjectE @ 2651 NONAME DATA 16
 	_ZN13QSwipeGesture19getStaticMetaObjectEv @ 2652 NONAME
-	_ZN13QSwipeGesture20setVerticalDirectionENS_14SwipeDirectionE @ 2653 NONAME
-	_ZN13QSwipeGesture22setHorizontalDirectionENS_14SwipeDirectionE @ 2654 NONAME
+	_ZN13QSwipeGesture20setVerticalDirectionENS_14SwipeDirectionE @ 2653 NONAME ABSENT
+	_ZN13QSwipeGesture22setHorizontalDirectionENS_14SwipeDirectionE @ 2654 NONAME ABSENT
 	_ZN13QSwipeGestureC1EP7QObject @ 2655 NONAME
 	_ZN13QSwipeGestureC2EP7QObject @ 2656 NONAME
 	_ZN13QTextDocument10adjustSizeEv @ 2657 NONAME
@@ -3124,7 +3124,7 @@ EXPORTS
 	_ZN14QWidgetPrivate20setLayoutItemMarginsEiiii @ 3123 NONAME
 	_ZN14QWidgetPrivate20setWindowIcon_helperEv @ 3124 NONAME
 	_ZN14QWidgetPrivate20setWindowOpacity_sysEf @ 3125 NONAME
-	_ZN14QWidgetPrivate21activateSymbianWindowEv @ 3126 NONAME
+	_ZN14QWidgetPrivate21activateSymbianWindowEv @ 3126 NONAME ABSENT
 	_ZN14QWidgetPrivate21setMaximumSize_helperERiS0_ @ 3127 NONAME
 	_ZN14QWidgetPrivate21setMinimumSize_helperERiS0_ @ 3128 NONAME
 	_ZN14QWidgetPrivate21setWindowIconText_sysERK7QString @ 3129 NONAME
@@ -6369,12 +6369,12 @@ EXPORTS
 	_ZN8QGesture15setTargetObjectEP7QObject @ 6368 NONAME
 	_ZN8QGesture16staticMetaObjectE @ 6369 NONAME DATA 16
 	_ZN8QGesture19getStaticMetaObjectEv @ 6370 NONAME
-	_ZN8QGestureC1EN2Qt11GestureTypeEP7QObject @ 6371 NONAME
+	_ZN8QGestureC1EN2Qt11GestureTypeEP7QObject @ 6371 NONAME ABSENT
 	_ZN8QGestureC1EP7QObject @ 6372 NONAME
-	_ZN8QGestureC1ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6373 NONAME
-	_ZN8QGestureC2EN2Qt11GestureTypeEP7QObject @ 6374 NONAME
+	_ZN8QGestureC1ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6373 NONAME ABSENT
+	_ZN8QGestureC2EN2Qt11GestureTypeEP7QObject @ 6374 NONAME ABSENT
 	_ZN8QGestureC2EP7QObject @ 6375 NONAME
-	_ZN8QGestureC2ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6376 NONAME
+	_ZN8QGestureC2ER15QGesturePrivateN2Qt11GestureTypeEP7QObject @ 6376 NONAME ABSENT
 	_ZN8QGestureD0Ev @ 6377 NONAME
 	_ZN8QGestureD1Ev @ 6378 NONAME
 	_ZN8QGestureD2Ev @ 6379 NONAME
@@ -11557,4 +11557,33 @@ EXPORTS
 	qt_pixmap_cleanup_hook @ 11556 NONAME DATA 4
 	qt_pixmap_cleanup_hook_64 @ 11557 NONAME DATA 4
 	qt_tab_all_widgets @ 11558 NONAME DATA 1
+	_Z22qt_paint_device_metricPK12QPaintDeviceNS_17PaintDeviceMetricE @ 11559 NONAME
+	_ZN14QWidgetPrivate17_q_delayedDestroyEP11CCoeControl @ 11560 NONAME
+	_ZN14QWidgetPrivate21activateSymbianWindowEP11CCoeControl @ 11561 NONAME
+	_ZN18QGuiPlatformPlugin11qt_metacallEN11QMetaObject4CallEiPPv @ 11562 NONAME
+	_ZN18QGuiPlatformPlugin11qt_metacastEPKc @ 11563 NONAME
+	_ZN18QGuiPlatformPlugin12platformHintENS_12PlatformHintE @ 11564 NONAME
+	_ZN18QGuiPlatformPlugin14fileSystemIconERK9QFileInfo @ 11565 NONAME
+	_ZN18QGuiPlatformPlugin16staticMetaObjectE @ 11566 NONAME DATA 16
+	_ZN18QGuiPlatformPlugin19getStaticMetaObjectEv @ 11567 NONAME
+	_ZN18QGuiPlatformPlugin19systemIconThemeNameEv @ 11568 NONAME
+	_ZN18QGuiPlatformPlugin20iconThemeSearchPathsEv @ 11569 NONAME
+	_ZN18QGuiPlatformPlugin7paletteEv @ 11570 NONAME
+	_ZN18QGuiPlatformPlugin9styleNameEv @ 11571 NONAME
+	_ZN18QGuiPlatformPluginC1EP7QObject @ 11572 NONAME
+	_ZN18QGuiPlatformPluginC2EP7QObject @ 11573 NONAME
+	_ZN18QGuiPlatformPluginD0Ev @ 11574 NONAME
+	_ZN18QGuiPlatformPluginD1Ev @ 11575 NONAME
+	_ZN18QGuiPlatformPluginD2Ev @ 11576 NONAME
+	_ZN8QGestureC1ER15QGesturePrivateP7QObject @ 11577 NONAME
+	_ZN8QGestureC2ER15QGesturePrivateP7QObject @ 11578 NONAME
+	_ZNK11QPixmapData26createCompatiblePixmapDataEv @ 11579 NONAME
+	_ZNK13QGestureEvent7gestureEN2Qt11GestureTypeE @ 11580 NONAME
+	_ZNK17QRasterPixmapData26createCompatiblePixmapDataEv @ 11581 NONAME
+	_ZNK18QGuiPlatformPlugin10metaObjectEv @ 11582 NONAME
+	_ZTI18QGuiPlatformPlugin @ 11583 NONAME
+	_ZTI27QGuiPlatformPluginInterface @ 11584 NONAME
+	_ZTV18QGuiPlatformPlugin @ 11585 NONAME
+	_ZThn8_N18QGuiPlatformPluginD0Ev @ 11586 NONAME
+	_ZThn8_N18QGuiPlatformPluginD1Ev @ 11587 NONAME
 
diff --git a/src/s60installs/eabi/QtMultimediau.def b/src/s60installs/eabi/QtMultimediau.def
index 787ad3a..c946056 100644
--- a/src/s60installs/eabi/QtMultimediau.def
+++ b/src/s60installs/eabi/QtMultimediau.def
@@ -115,8 +115,8 @@ EXPORTS
 	_ZN19QAbstractAudioInput6notifyEv @ 114 NONAME
 	_ZN19QVideoSurfaceFormat11setPropertyEPKcRK8QVariant @ 115 NONAME
 	_ZN19QVideoSurfaceFormat11setViewportERK5QRect @ 116 NONAME
-	_ZN19QVideoSurfaceFormat12setFrameRateERK5QPairIiiE @ 117 NONAME
-	_ZN19QVideoSurfaceFormat12setFrameRateEii @ 118 NONAME
+	_ZN19QVideoSurfaceFormat12setFrameRateERK5QPairIiiE @ 117 NONAME ABSENT
+	_ZN19QVideoSurfaceFormat12setFrameRateEii @ 118 NONAME ABSENT
 	_ZN19QVideoSurfaceFormat12setFrameSizeERK5QSizeNS_12ViewportModeE @ 119 NONAME
 	_ZN19QVideoSurfaceFormat12setFrameSizeEiiNS_12ViewportModeE @ 120 NONAME
 	_ZN19QVideoSurfaceFormat16setYuvColorSpaceENS_13YuvColorSpaceE @ 121 NONAME
@@ -275,4 +275,5 @@ EXPORTS
 	_ZThn8_N18QAudioEnginePluginD0Ev @ 274 NONAME
 	_ZThn8_N18QAudioEnginePluginD1Ev @ 275 NONAME
 	_Zls6QDebugRK19QVideoSurfaceFormat @ 276 NONAME
+	_ZN19QVideoSurfaceFormat12setFrameRateEf @ 277 NONAME
 
diff --git a/src/s60installs/eabi/QtNetworku.def b/src/s60installs/eabi/QtNetworku.def
index f216f85..c37c4a0 100644
--- a/src/s60installs/eabi/QtNetworku.def
+++ b/src/s60installs/eabi/QtNetworku.def
@@ -989,4 +989,8 @@ EXPORTS
 	_ZlsR11QDataStreamRK21QNetworkCacheMetaData @ 988 NONAME
 	_ZrsR11QDataStreamR12QHostAddress @ 989 NONAME
 	_ZrsR11QDataStreamR21QNetworkCacheMetaData @ 990 NONAME
+	_ZN10QSslSocket12socketOptionEN15QAbstractSocket12SocketOptionE @ 991 NONAME
+	_ZN10QSslSocket15setSocketOptionEN15QAbstractSocket12SocketOptionERK8QVariant @ 992 NONAME
+	_ZN15QNetworkRequest20setOriginatingObjectEP7QObject @ 993 NONAME
+	_ZNK15QNetworkRequest17originatingObjectEv @ 994 NONAME
 
diff --git a/src/s60installs/eabi/QtScriptu.def b/src/s60installs/eabi/QtScriptu.def
index d0a3e3e..1592664 100644
--- a/src/s60installs/eabi/QtScriptu.def
+++ b/src/s60installs/eabi/QtScriptu.def
@@ -341,4 +341,5 @@ EXPORTS
 	_ZThn8_N22QScriptExtensionPluginD1Ev @ 340 NONAME
 	_ZlsR11QDataStreamRK18QScriptContextInfo @ 341 NONAME
 	_ZrsR11QDataStreamR18QScriptContextInfo @ 342 NONAME
+	_Z5qHashRK13QScriptString @ 343 NONAME
 
diff --git a/src/s60installs/eabi/phononu.def b/src/s60installs/eabi/phononu.def
index 651a0b8..af1e3cc 100644
--- a/src/s60installs/eabi/phononu.def
+++ b/src/s60installs/eabi/phononu.def
@@ -534,4 +534,14 @@ EXPORTS
 	_ZThn8_N6Phonon19AbstractAudioOutputD1Ev @ 533 NONAME
 	_ZThn8_N6Phonon6EffectD0Ev @ 534 NONAME
 	_ZThn8_N6Phonon6EffectD1Ev @ 535 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE0EEE @ 536 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE1EEE @ 537 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE2EEE @ 538 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE3EEE @ 539 NONAME
+	_ZTIN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE4EEE @ 540 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE0EEE @ 541 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE1EEE @ 542 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE2EEE @ 543 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE3EEE @ 544 NONAME
+	_ZTVN6Phonon22ObjectDescriptionModelILNS_21ObjectDescriptionTypeE4EEE @ 545 NONAME
 
-- 
cgit v0.12


From 0cb251e67ae45d8ab5ad715a4bc6dcf89209d2ab Mon Sep 17 00:00:00 2001
From: Kurt Korbatits <kurt.korbatits@nokia.com>
Date: Wed, 21 Oct 2009 14:29:34 +1000
Subject: Fixed compile issue with alsa < 1.0.14 Support pre 1.0.14 alsa
 version.

Reviewed-by:Justin McPherson
---
 src/multimedia/audio/qaudiodeviceinfo_alsa_p.cpp | 40 ++++++++++++++++++++++--
 src/multimedia/audio/qaudioinput_alsa_p.cpp      | 19 ++++++++++-
 src/multimedia/audio/qaudioinput_alsa_p.h        |  1 +
 src/multimedia/audio/qaudiooutput_alsa_p.cpp     | 17 ++++++++++
 src/multimedia/audio/qaudiooutput_alsa_p.h       |  1 +
 5 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/src/multimedia/audio/qaudiodeviceinfo_alsa_p.cpp b/src/multimedia/audio/qaudiodeviceinfo_alsa_p.cpp
index 55020a6..e828238 100644
--- a/src/multimedia/audio/qaudiodeviceinfo_alsa_p.cpp
+++ b/src/multimedia/audio/qaudiodeviceinfo_alsa_p.cpp
@@ -52,6 +52,8 @@
 
 #include "qaudiodeviceinfo_alsa_p.h"
 
+#include <alsa/version.h>
+
 QT_BEGIN_NAMESPACE
 
 QAudioDeviceInfoInternal::QAudioDeviceInfoInternal(QByteArray dev, QAudio::Mode mode)
@@ -151,8 +153,19 @@ bool QAudioDeviceInfoInternal::open()
     int err = 0;
     QString dev = device;
     if(!dev.contains(QLatin1String("default"))) {
-        int idx = snd_card_get_index(dev.toLocal8Bit().constData());
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14)
+         dev = QString(QLatin1String("default:CARD=%1")).arg(dev);
+#else
+        int idx = 0;
+        char *name;
+
+	while(snd_card_get_name(idx,&name) == 0) {
+            if(dev.contains(QLatin1String(name)))
+                break;
+            idx++;
+	}
         dev = QString(QLatin1String("hw:%1,0")).arg(idx);
+#endif
     }
     if(mode == QAudio::AudioOutput) {
         err=snd_pcm_open( &handle,dev.toLocal8Bit().constData(),SND_PCM_STREAM_PLAYBACK,0);
@@ -184,8 +197,19 @@ bool QAudioDeviceInfoInternal::testSettings(const QAudioFormat& format) const
 
     // open()
     if(!dev.contains(QLatin1String("default"))) {
-        int idx = snd_card_get_index(dev.toLocal8Bit().constData());
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14)
+         dev = QString(QLatin1String("default:CARD=%1")).arg(dev);
+#else
+        int idx = 0;
+        char *name;
+    
+        while(snd_card_get_name(idx,&name) == 0) {
+            if(dev.contains(QLatin1String(name)))
+                break;
+            idx++;
+        }
         dev = QString(QLatin1String("hw:%1,0")).arg(idx);
+#endif
     }
     if(mode == QAudio::AudioOutput) {
         err=snd_pcm_open( &handle,dev.toLocal8Bit().constData(),SND_PCM_STREAM_PLAYBACK,0);
@@ -362,7 +386,7 @@ QList<QByteArray> QAudioDeviceInfoInternal::deviceList(QAudio::Mode mode)
 {
     QList<QByteArray> devices;
     QByteArray filter;
-
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14)
     // Create a list of all current audio devices that support mode
     void **hints, **n;
     char *name, *descr, *io;
@@ -404,7 +428,17 @@ QList<QByteArray> QAudioDeviceInfoInternal::deviceList(QAudio::Mode mode)
     if(devices.size() > 0) {
         devices.append("default");
     }
+#else
+    int idx = 0;
+    char* name;
 
+    while(snd_card_get_name(idx,&name) == 0) {
+        devices.append(name);
+        idx++;
+    }
+    if (idx > 0)
+        devices.append("default");
+#endif
     return devices;
 }
 
diff --git a/src/multimedia/audio/qaudioinput_alsa_p.cpp b/src/multimedia/audio/qaudioinput_alsa_p.cpp
index 5e9aa81..6786657 100644
--- a/src/multimedia/audio/qaudioinput_alsa_p.cpp
+++ b/src/multimedia/audio/qaudioinput_alsa_p.cpp
@@ -249,6 +249,7 @@ bool QAudioInputPrivate::open()
     QTime now(QTime::currentTime());
     qDebug()<<now.second()<<"s "<<now.msec()<<"ms :open()";
 #endif
+    clockStamp.restart();
     timeStamp.restart();
     elapsedTimeOffset = 0;
 
@@ -259,9 +260,21 @@ bool QAudioInputPrivate::open()
 
     QString dev = QString(QLatin1String(m_device.constData()));
     if(!dev.contains(QLatin1String("default"))) {
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14) 
         dev = QString(QLatin1String("default:CARD=%1")).arg(QLatin1String(m_device.constData()));
-    }
+#else
+        int idx = 0;
+        char *name;
 
+        while(snd_card_get_name(idx,&name) == 0) {
+            if(m_device.contains(name))
+                break;
+            idx++;
+        }
+        dev = QString(QLatin1String("hw:%1,0")).arg(idx);
+#endif
+    }
+    
     // Step 1: try and open the device
     while((count < 5) && (err < 0)) {
         err=snd_pcm_open(&handle,dev.toLocal8Bit().constData(),SND_PCM_STREAM_CAPTURE,0);
@@ -601,6 +614,7 @@ qint64 QAudioInputPrivate::clock() const
     if (deviceState == QAudio::StopState)
         return 0;
 
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14) 
     snd_pcm_status_t* status;
     snd_pcm_status_alloca(&status);
 
@@ -619,6 +633,9 @@ qint64 QAudioInputPrivate::clock() const
         return ((t1.tv_sec * 1000)+l/1000);
     } else
         return 0;
+#else
+    return clockStamp.elapsed()*1000;
+#endif
 }
 
 void QAudioInputPrivate::reset()
diff --git a/src/multimedia/audio/qaudioinput_alsa_p.h b/src/multimedia/audio/qaudioinput_alsa_p.h
index 5583ea0..2ed7453 100644
--- a/src/multimedia/audio/qaudioinput_alsa_p.h
+++ b/src/multimedia/audio/qaudioinput_alsa_p.h
@@ -117,6 +117,7 @@ private:
 
     QTimer* timer;
     QTime timeStamp;
+    QTime clockStamp;
     qint64 elapsedTimeOffset;
     int intervalTime;
     char* audioBuffer;
diff --git a/src/multimedia/audio/qaudiooutput_alsa_p.cpp b/src/multimedia/audio/qaudiooutput_alsa_p.cpp
index d814d97..efa7b27 100644
--- a/src/multimedia/audio/qaudiooutput_alsa_p.cpp
+++ b/src/multimedia/audio/qaudiooutput_alsa_p.cpp
@@ -282,7 +282,19 @@ bool QAudioOutputPrivate::open()
 
     QString dev = QLatin1String(m_device.constData());
     if(!dev.contains(QLatin1String("default"))) {
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14) 
         dev = QString(QLatin1String("default:CARD=%1")).arg(QLatin1String(m_device.constData()));
+#else
+        int idx = 0;
+        char *name;
+
+	while(snd_card_get_name(idx,&name) == 0) {
+            if(m_device.contains(name))
+                break;
+            idx++;
+	}
+        dev = QString(QLatin1String("hw:%1,0")).arg(idx);
+#endif
     }
     // Step 1: try and open the device
     while((count < 5) && (err < 0)) {
@@ -407,6 +419,7 @@ bool QAudioOutputPrivate::open()
     // Step 6: Start audio processing
     timer->start(period_time/1000);
 
+    clockStamp.restart();
     timeStamp.restart();
     elapsedTimeOffset = 0;
     errorState  = QAudio::NoError;
@@ -653,6 +666,7 @@ qint64 QAudioOutputPrivate::clock() const
     if (deviceState == QAudio::StopState)
         return 0;
 
+#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14) 
     snd_pcm_status_t* status;
     snd_pcm_status_alloca(&status);
 
@@ -671,6 +685,9 @@ qint64 QAudioOutputPrivate::clock() const
         return ((t1.tv_sec * 1000)+l/1000);
     } else
         return 0;
+#else
+    return clockStamp.elapsed()*1000;
+#endif
     return 0;
 }
 
diff --git a/src/multimedia/audio/qaudiooutput_alsa_p.h b/src/multimedia/audio/qaudiooutput_alsa_p.h
index 6d4177d..298e89e 100644
--- a/src/multimedia/audio/qaudiooutput_alsa_p.h
+++ b/src/multimedia/audio/qaudiooutput_alsa_p.h
@@ -134,6 +134,7 @@ private:
     QByteArray m_device;
     int bytesAvailable;
     QTime timeStamp;
+    QTime clockStamp;
     qint64 elapsedTimeOffset;
     char* audioBuffer;
     snd_pcm_t* handle;
-- 
cgit v0.12


From bbbf570f8a590b4d9ea2f8b2de592ea790f9cd50 Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Wed, 21 Oct 2009 12:17:16 +1000
Subject: Update sqlite to 3.6.19

---
 src/3rdparty/sqlite/sqlite3.c | 153279 ++++++++++++++++++++++-----------------
 src/3rdparty/sqlite/sqlite3.h |   6329 +-
 2 files changed, 91653 insertions(+), 67955 deletions(-)

diff --git a/src/3rdparty/sqlite/sqlite3.c b/src/3rdparty/sqlite/sqlite3.c
index 7e604cb..8ca6a82 100644
--- a/src/3rdparty/sqlite/sqlite3.c
+++ b/src/3rdparty/sqlite/sqlite3.c
@@ -1,6 +1,6 @@
 /******************************************************************************
 ** This file is an amalgamation of many separate C source files from SQLite
-** version 3.5.9.  By combining all the individual C code files into this 
+** version 3.6.19.  By combining all the individual C code files into this 
 ** single large file, the entire code can be compiled as a one translation
 ** unit.  This allows many compilers to do optimizations that would not be
 ** possible if the files were compiled separately.  Performance improvements
@@ -10,14 +10,14 @@
 ** This file is all you need to compile SQLite.  To use SQLite in other
 ** programs, you need this file and the "sqlite3.h" header file that defines
 ** the programming interface to the SQLite library.  (If you do not have 
-** the "sqlite3.h" header file at hand, you will find a copy in the first
-** 5638 lines past this header comment.)  Additional code files may be
-** needed if you want a wrapper to interface SQLite with your choice of
-** programming language.  The code for the "sqlite3" command-line shell
-** is also in a separate file.  This file contains only code for the core
-** SQLite library.
+** the "sqlite3.h" header file at hand, you will find a copy embedded within
+** the text of this file.  Search for "Begin file sqlite3.h" to find the start
+** of the embedded sqlite3.h header file.) Additional code files may be needed
+** if you want a wrapper to interface SQLite with your choice of programming
+** language. The code for the "sqlite3" command-line shell is also in a
+** separate file. This file contains only code for the core SQLite library.
 **
-** This amalgamation was generated on 2008-05-14 16:20:58 UTC.
+** This amalgamation was generated on 2009-10-14 11:35:02 UTC.
 */
 #define SQLITE_CORE 1
 #define SQLITE_AMALGAMATION 1
@@ -41,12 +41,38 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.704 2008/05/13 13:27:34 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
 
 /*
+** These #defines should enable >2GB file support on POSIX if the
+** underlying operating system supports it.  If the OS lacks
+** large file support, or if the OS is windows, these should be no-ops.
+**
+** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
+** system #includes.  Hence, this block of code must be the very first
+** code in all source files.
+**
+** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
+** on the compiler command line.  This is necessary if you are compiling
+** on a recent machine (ex: Red Hat 7.2) but you want your code to work
+** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
+** without this option, LFS is enable.  But LFS does not exist in the kernel
+** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
+** portability you should omit LFS.
+**
+** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
+*/
+#ifndef SQLITE_DISABLE_LFS
+# define _LARGE_FILE       1
+# ifndef _FILE_OFFSET_BITS
+#   define _FILE_OFFSET_BITS 64
+# endif
+# define _LARGEFILE_SOURCE 1
+#endif
+
+/*
 ** Include the configuration header output by 'configure' if we're using the
 ** autoconf-based build
 */
@@ -70,7 +96,7 @@
 ** 
 ** This file defines various limits of what SQLite can process.
 **
-** @(#) $Id: sqliteLimit.h,v 1.8 2008/03/26 15:56:22 drh Exp $
+** @(#) $Id: sqliteLimit.h,v 1.10 2009/01/10 16:15:09 danielk1977 Exp $
 */
 
 /*
@@ -154,7 +180,7 @@
 ** The maximum number of arguments to an SQL function.
 */
 #ifndef SQLITE_MAX_FUNCTION_ARG
-# define SQLITE_MAX_FUNCTION_ARG 100
+# define SQLITE_MAX_FUNCTION_ARG 127
 #endif
 
 /*
@@ -188,6 +214,13 @@
 /* Maximum page size.  The upper bound on this value is 32768.  This a limit
 ** imposed by the necessity of storing the value in a 2-byte unsigned integer
 ** and the fact that the page size must be a power of 2.
+**
+** If this limit is changed, then the compiled library is technically
+** incompatible with an SQLite library compiled with a different limit. If
+** a process operating on a database with a page-size of 65536 bytes 
+** crashes, then an instance of SQLite compiled with the default page-size 
+** limit will not be able to rollback the aborted transaction. This could
+** lead to database corruption.
 */
 #ifndef SQLITE_MAX_PAGE_SIZE
 # define SQLITE_MAX_PAGE_SIZE 32768
@@ -240,6 +273,21 @@
 # define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
 #endif
 
+/*
+** Maximum depth of recursion for triggers.
+**
+** A value of 1 means that a trigger program will not be able to itself
+** fire any triggers. A value of 0 means that no trigger programs at all 
+** may be executed.
+*/
+#ifndef SQLITE_MAX_TRIGGER_DEPTH
+#if defined(SQLITE_SMALL_STACK)
+# define SQLITE_MAX_TRIGGER_DEPTH 10
+#else
+# define SQLITE_MAX_TRIGGER_DEPTH 1000
+#endif
+#endif
+
 /************** End of sqliteLimit.h *****************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
 
@@ -249,11 +297,13 @@
 #pragma warn -ccc /* Condition is always true or false */
 #pragma warn -aus /* Assigned value is never used */
 #pragma warn -csu /* Comparing signed and unsigned */
-#pragma warn -spa /* Suspicous pointer arithmetic */
+#pragma warn -spa /* Suspicious pointer arithmetic */
 #endif
 
 /* Needed for various definitions... */
-#define _GNU_SOURCE
+#ifndef _GNU_SOURCE
+# define _GNU_SOURCE
+#endif
 
 /*
 ** Include standard header files as necessary
@@ -265,61 +315,38 @@
 #include <inttypes.h>
 #endif
 
-/*
-** A macro used to aid in coverage testing.  When doing coverage
-** testing, the condition inside the argument must be evaluated 
-** both true and false in order to get full branch coverage.
-** This macro can be inserted to ensure adequate test coverage
-** in places where simple condition/decision coverage is inadequate.
-*/
-#ifdef SQLITE_COVERAGE_TEST
-SQLITE_PRIVATE   void sqlite3Coverage(int);
-# define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
-#else
-# define testcase(X)
-#endif
-
-
-/*
-** The macro unlikely() is a hint that surrounds a boolean
-** expression that is usually false.  Macro likely() surrounds
-** a boolean expression that is usually true.  GCC is able to
-** use these hints to generate better code, sometimes.
-*/
-#if defined(__GNUC__) && 0
-# define likely(X)    __builtin_expect((X),1)
-# define unlikely(X)  __builtin_expect((X),0)
-#else
-# define likely(X)    !!(X)
-# define unlikely(X)  !!(X)
-#endif
-
+#define SQLITE_INDEX_SAMPLES 10
 
 /*
-** These #defines should enable >2GB file support on Posix if the
-** underlying operating system supports it.  If the OS lacks
-** large file support, or if the OS is windows, these should be no-ops.
+** This macro is used to "hide" some ugliness in casting an int
+** value to a ptr value under the MSVC 64-bit compiler.   Casting
+** non 64-bit values to ptr types results in a "hard" error with 
+** the MSVC 64-bit compiler which this attempts to avoid.  
 **
-** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
-** system #includes.  Hence, this block of code must be the very first
-** code in all source files.
+** A simple compiler pragma or casting sequence could not be found
+** to correct this in all situations, so this macro was introduced.
 **
-** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
-** on the compiler command line.  This is necessary if you are compiling
-** on a recent machine (ex: RedHat 7.2) but you want your code to work
-** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
-** without this option, LFS is enable.  But LFS does not exist in the kernel
-** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
-** portability you should omit LFS.
+** It could be argued that the intptr_t type could be used in this
+** case, but that type is not available on all compilers, or 
+** requires the #include of specific headers which differs between
+** platforms.
 **
-** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
+** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
+** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
+** So we have to define the macros in different ways depending on the
+** compiler.
 */
-#ifndef SQLITE_DISABLE_LFS
-# define _LARGE_FILE       1
-# ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
+#if defined(__GNUC__)
+# if defined(HAVE_STDINT_H)
+#   define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
+#   define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
+# else
+#   define SQLITE_INT_TO_PTR(X)  ((void*)(X))
+#   define SQLITE_PTR_TO_INT(X)  ((int)(X))
 # endif
-# define _LARGEFILE_SOURCE 1
+#else
+# define SQLITE_INT_TO_PTR(X)   ((void*)&((char*)0)[X])
+# define SQLITE_PTR_TO_INT(X)   ((int)(((char*)X)-(char*)0))
 #endif
 
 
@@ -337,6 +364,16 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 #endif
 
 /*
+** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
+** It determines whether or not the features related to 
+** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
+** be overridden at runtime using the sqlite3_config() API.
+*/
+#if !defined(SQLITE_DEFAULT_MEMSTATUS)
+# define SQLITE_DEFAULT_MEMSTATUS 1
+#endif
+
+/*
 ** Exactly one of the following macros must be defined in order to
 ** specify which memory allocation subsystem to use.
 **
@@ -363,16 +400,16 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 #endif
 
 /*
-** If SQLITE_MALLOC_SOFT_LIMIT is defined, then try to keep the
+** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
 ** sizes of memory allocations below this value where possible.
 */
-#if defined(SQLITE_POW2_MEMORY_SIZE) && !defined(SQLITE_MALLOC_SOFT_LIMIT)
+#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
 # define SQLITE_MALLOC_SOFT_LIMIT 1024
 #endif
 
 /*
 ** We need to define _XOPEN_SOURCE as follows in order to enable
-** recursive mutexes on most unix systems.  But Mac OS X is different.
+** recursive mutexes on most Unix systems.  But Mac OS X is different.
 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
 ** so it is omitted there.  See ticket #2673.
 **
@@ -383,10 +420,13 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 **
 ** See also ticket #2741.
 */
-#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE && !defined(VXWORKS)
+#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
 #endif
 
+/*
+** The TCL headers are only needed when compiling the TCL bindings.
+*/
 #if defined(SQLITE_TCL) || defined(TCLSH)
 # include <tcl.h>
 #endif
@@ -402,6 +442,92 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 # define NDEBUG 1
 #endif
 
+/*
+** The testcase() macro is used to aid in coverage testing.  When 
+** doing coverage testing, the condition inside the argument to
+** testcase() must be evaluated both true and false in order to
+** get full branch coverage.  The testcase() macro is inserted
+** to help ensure adequate test coverage in places where simple
+** condition/decision coverage is inadequate.  For example, testcase()
+** can be used to make sure boundary values are tested.  For
+** bitmask tests, testcase() can be used to make sure each bit
+** is significant and used at least once.  On switch statements
+** where multiple cases go to the same block of code, testcase()
+** can insure that all cases are evaluated.
+**
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE   void sqlite3Coverage(int);
+# define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
+#else
+# define testcase(X)
+#endif
+
+/*
+** The TESTONLY macro is used to enclose variable declarations or
+** other bits of code that are needed to support the arguments
+** within testcase() and assert() macros.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
+# define TESTONLY(X)  X
+#else
+# define TESTONLY(X)
+#endif
+
+/*
+** Sometimes we need a small amount of code such as a variable initialization
+** to setup for a later assert() statement.  We do not want this code to
+** appear when assert() is disabled.  The following macro is therefore
+** used to contain that setup code.  The "VVA" acronym stands for
+** "Verification, Validation, and Accreditation".  In other words, the
+** code within VVA_ONLY() will only run during verification processes.
+*/
+#ifndef NDEBUG
+# define VVA_ONLY(X)  X
+#else
+# define VVA_ONLY(X)
+#endif
+
+/*
+** The ALWAYS and NEVER macros surround boolean expressions which 
+** are intended to always be true or false, respectively.  Such
+** expressions could be omitted from the code completely.  But they
+** are included in a few cases in order to enhance the resilience
+** of SQLite to unexpected behavior - to make the code "self-healing"
+** or "ductile" rather than being "brittle" and crashing at the first
+** hint of unplanned behavior.
+**
+** In other words, ALWAYS and NEVER are added for defensive code.
+**
+** When doing coverage testing ALWAYS and NEVER are hard-coded to
+** be true and false so that the unreachable code then specify will
+** not be counted as untested code.
+*/
+#if defined(SQLITE_COVERAGE_TEST)
+# define ALWAYS(X)      (1)
+# define NEVER(X)       (0)
+#elif !defined(NDEBUG)
+# define ALWAYS(X)      ((X)?1:(assert(0),0))
+# define NEVER(X)       ((X)?(assert(0),1):0)
+#else
+# define ALWAYS(X)      (X)
+# define NEVER(X)       (X)
+#endif
+
+/*
+** The macro unlikely() is a hint that surrounds a boolean
+** expression that is usually false.  Macro likely() surrounds
+** a boolean expression that is usually true.  GCC is able to
+** use these hints to generate better code, sometimes.
+*/
+#if defined(__GNUC__) && 0
+# define likely(X)    __builtin_expect((X),1)
+# define unlikely(X)  __builtin_expect((X),0)
+#else
+# define likely(X)    !!(X)
+# define unlikely(X)  !!(X)
+#endif
+
 /************** Include sqlite3.h in the middle of sqliteInt.h ***************/
 /************** Begin file sqlite3.h *****************************************/
 /*
@@ -423,9 +549,9 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 **
 ** Some of the definitions that are in this file are marked as
 ** "experimental".  Experimental interfaces are normally new
-** features recently added to SQLite.  We do not anticipate changes 
-** to experimental interfaces but reserve to make minor changes if
-** experience from use "in the wild" suggest such changes are prudent.
+** features recently added to SQLite.  We do not anticipate changes
+** to experimental interfaces but reserve the right to make minor changes
+** if experience from use "in the wild" suggest such changes are prudent.
 **
 ** The official C-language API documentation for SQLite is derived
 ** from comments in this file.  This file is the authoritative source
@@ -435,18 +561,9 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 ** The makefile makes some minor changes to this file (such as inserting
 ** the version number) and changes its name to "sqlite3.h" as
 ** part of the build process.
-**
-** @(#) $Id: sqlite.h.in,v 1.312 2008/05/12 12:39:56 drh Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
-
-#ifdef VXWORKS
-# define SQLITE_HOMEGROWN_RECURSIVE_MUTEX
-# define NO_GETTOD
-# include <ioLib.h>
-#endif
-
 #include <stdarg.h>     /* Needed for the definition of va_list */
 
 /*
@@ -464,9 +581,29 @@ extern "C" {
 # define SQLITE_EXTERN extern
 #endif
 
+#ifndef SQLITE_API
+# define SQLITE_API
+#endif
+
+
 /*
-** Make sure these symbols where not defined by some previous header
-** file.
+** These no-op macros are used in front of interfaces to mark those
+** interfaces as either deprecated or experimental.  New applications
+** should not use deprecated interfaces - they are support for backwards
+** compatibility only.  Application writers should be aware that
+** experimental interfaces are subject to change in point releases.
+**
+** These macros used to resolve to various kinds of compiler magic that
+** would generate warning messages when they were used.  But that
+** compiler magic ended up generating such a flurry of bug reports
+** that we have taken it all out and gone back to using simple
+** noop macros.
+*/
+#define SQLITE_DEPRECATED
+#define SQLITE_EXPERIMENTAL
+
+/*
+** Ensure these symbols were not defined by some previous header file.
 */
 #ifdef SQLITE_VERSION
 # undef SQLITE_VERSION
@@ -476,130 +613,143 @@ extern "C" {
 #endif
 
 /*
-** CAPI3REF: Compile-Time Library Version Numbers {F10010}
+** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
 **
 ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
 ** the sqlite3.h file specify the version of SQLite with which
 ** that header file is associated.
 **
-** The "version" of SQLite is a string of the form "X.Y.Z".
-** The phrase "alpha" or "beta" might be appended after the Z.
-** The X value is major version number always 3 in SQLite3.
-** The X value only changes when  backwards compatibility is
-** broken and we intend to never break
-** backwards compatibility.  The Y value is the minor version
-** number and only changes when
+** The "version" of SQLite is a string of the form "W.X.Y" or "W.X.Y.Z".
+** The W value is major version number and is always 3 in SQLite3.
+** The W value only changes when backwards compatibility is
+** broken and we intend to never break backwards compatibility.
+** The X value is the minor version number and only changes when
 ** there are major feature enhancements that are forwards compatible
-** but not backwards compatible.  The Z value is release number
-** and is incremented with
-** each release but resets back to 0 when Y is incremented.
+** but not backwards compatible.
+** The Y value is the release number and is incremented with
+** each release but resets back to 0 whenever X is incremented.
+** The Z value only appears on branch releases.
 **
-** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
+** The SQLITE_VERSION_NUMBER is an integer that is computed as
+** follows:
+**
+** <blockquote><pre>
+** SQLITE_VERSION_NUMBER = W*1000000 + X*1000 + Y
+** </pre></blockquote>
 **
-** INVARIANTS:
+** Since version 3.6.18, SQLite source code has been stored in the
+** <a href="http://www.fossil-scm.org/">fossil configuration management
+** system</a>.  The SQLITE_SOURCE_ID
+** macro is a string which identifies a particular check-in of SQLite
+** within its configuration management system.  The string contains the
+** date and time of the check-in (UTC) and an SHA1 hash of the entire
+** source tree.
 **
-** {F10011} The SQLITE_VERSION #define in the sqlite3.h header file
-**          evaluates to a string literal that is the SQLite version
-**          with which the header file is associated.
+** See also: [sqlite3_libversion()],
+** [sqlite3_libversion_number()], [sqlite3_sourceid()],
+** [sqlite_version()] and [sqlite_source_id()].
 **
-** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer
-**          with the value  (X*1000000 + Y*1000 + Z) where X, Y, and
-**          Z are the major version, minor version, and release number.
+** Requirements: [H10011] [H10014]
 */
-#define SQLITE_VERSION         "3.5.9"
-#define SQLITE_VERSION_NUMBER  3005009
+#define SQLITE_VERSION        "3.6.19"
+#define SQLITE_VERSION_NUMBER 3006019
+#define SQLITE_SOURCE_ID      "2009-10-14 11:33:55 c1d499afc50d54b376945b4efb65c56c787a073d"
 
 /*
-** CAPI3REF: Run-Time Library Version Numbers {F10020}
+** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
 ** KEYWORDS: sqlite3_version
 **
-** These features provide the same information as the [SQLITE_VERSION]
-** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
-** with the library instead of the header file.  Cautious programmers might
-** include a check in their application to verify that 
-** sqlite3_libversion_number() always returns the value 
-** [SQLITE_VERSION_NUMBER].
+** These interfaces provide the same information as the [SQLITE_VERSION],
+** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] #defines in the header,
+** but are associated with the library instead of the header file.  Cautious
+** programmers might include assert() statements in their application to
+** verify that values returned by these interfaces match the macros in
+** the header, and thus insure that the application is
+** compiled with matching library and header files.
+**
+** <blockquote><pre>
+** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
+** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
+** assert( strcmp(sqlite3_libversion,SQLITE_VERSION)==0 );
+** </pre></blockquote>
 **
 ** The sqlite3_libversion() function returns the same information as is
 ** in the sqlite3_version[] string constant.  The function is provided
 ** for use in DLLs since DLL users usually do not have direct access to string
-** constants within the DLL.
-**
-** INVARIANTS:
+** constants within the DLL.  Similarly, the sqlite3_sourceid() function
+** returns the same information as is in the [SQLITE_SOURCE_ID] #define of
+** the header file.
 **
-** {F10021} The [sqlite3_libversion_number()] interface returns an integer
-**          equal to [SQLITE_VERSION_NUMBER]. 
+** See also: [sqlite_version()] and [sqlite_source_id()].
 **
-** {F10022} The [sqlite3_version] string constant contains the text of the
-**          [SQLITE_VERSION] string. 
-**
-** {F10023} The [sqlite3_libversion()] function returns
-**          a pointer to the [sqlite3_version] string constant.
+** Requirements: [H10021] [H10022] [H10023]
 */
-SQLITE_API const char sqlite3_version[];
+SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
 SQLITE_API const char *sqlite3_libversion(void);
+SQLITE_API const char *sqlite3_sourceid(void);
 SQLITE_API int sqlite3_libversion_number(void);
 
 /*
-** CAPI3REF: Test To See If The Library Is Threadsafe {F10100}
+** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
 **
 ** SQLite can be compiled with or without mutexes.  When
-** the SQLITE_THREADSAFE C preprocessor macro is true, mutexes
-** are enabled and SQLite is threadsafe.  When that macro is false,
+** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
+** are enabled and SQLite is threadsafe.  When the
+** [SQLITE_THREADSAFE] macro is 0, 
 ** the mutexes are omitted.  Without the mutexes, it is not safe
-** to use SQLite from more than one thread.
+** to use SQLite concurrently from more than one thread.
 **
-** There is a measurable performance penalty for enabling mutexes.
+** Enabling mutexes incurs a measurable performance penalty.
 ** So if speed is of utmost importance, it makes sense to disable
 ** the mutexes.  But for maximum safety, mutexes should be enabled.
 ** The default behavior is for mutexes to be enabled.
 **
-** This interface can be used by a program to make sure that the
+** This interface can be used by an application to make sure that the
 ** version of SQLite that it is linking against was compiled with
-** the desired setting of the SQLITE_THREADSAFE macro.
+** the desired setting of the [SQLITE_THREADSAFE] macro.
 **
-** INVARIANTS:
+** This interface only reports on the compile-time mutex setting
+** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
+** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
+** can be fully or partially disabled using a call to [sqlite3_config()]
+** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
+** or [SQLITE_CONFIG_MUTEX].  The return value of this function shows
+** only the default compile-time setting, not any run-time changes
+** to that setting.
 **
-** {F10101} The [sqlite3_threadsafe()] function returns nonzero if
-**          SQLite was compiled with its mutexes enabled or zero
-**          if SQLite was compiled with mutexes disabled.
+** See the [threading mode] documentation for additional information.
+**
+** Requirements: [H10101] [H10102]
 */
 SQLITE_API int sqlite3_threadsafe(void);
 
 /*
-** CAPI3REF: Database Connection Handle {F12000}
+** CAPI3REF: Database Connection Handle {H12000} <S40200>
 ** KEYWORDS: {database connection} {database connections}
 **
-** Each open SQLite database is represented by pointer to an instance of the
-** opaque structure named "sqlite3".  It is useful to think of an sqlite3
+** Each open SQLite database is represented by a pointer to an instance of
+** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
 ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
-** [sqlite3_open_v2()] interfaces are its constructors
-** and [sqlite3_close()] is its destructor.  There are many other interfaces
-** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and
-** [sqlite3_busy_timeout()] to name but three) that are methods on this
-** object.
+** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
+** is its destructor.  There are many other interfaces (such as
+** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
+** [sqlite3_busy_timeout()] to name but three) that are methods on an
+** sqlite3 object.
 */
 typedef struct sqlite3 sqlite3;
 
-
 /*
-** CAPI3REF: 64-Bit Integer Types {F10200}
+** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
 ** KEYWORDS: sqlite_int64 sqlite_uint64
 **
 ** Because there is no cross-platform way to specify 64-bit integer types
 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
 **
-** The sqlite3_int64 and sqlite3_uint64 are the preferred type
-** definitions.  The sqlite_int64 and sqlite_uint64 types are
-** supported for backwards compatibility only.
-**
-** INVARIANTS:
+** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
+** The sqlite_int64 and sqlite_uint64 types are supported for backwards
+** compatibility only.
 **
-** {F10201} The [sqlite_int64] and [sqlite3_int64] types specify a
-**          64-bit signed integer.
-**
-** {F10202} The [sqlite_uint64] and [sqlite3_uint64] types specify
-**          a 64-bit unsigned integer.
+** Requirements: [H10201] [H10202]
 */
 #ifdef SQLITE_INT64_TYPE
   typedef SQLITE_INT64_TYPE sqlite_int64;
@@ -616,50 +766,41 @@ typedef sqlite_uint64 sqlite3_uint64;
 
 /*
 ** If compiling for a processor that lacks floating point support,
-** substitute integer for floating-point
+** substitute integer for floating-point.
 */
 #ifdef SQLITE_OMIT_FLOATING_POINT
 # define double sqlite3_int64
 #endif
 
 /*
-** CAPI3REF: Closing A Database Connection {F12010}
+** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
 **
-** This routine is the destructor for the [sqlite3] object.  
+** This routine is the destructor for the [sqlite3] object.
 **
-** Applications should [sqlite3_finalize | finalize] all
-** [prepared statements] and
-** [sqlite3_blob_close | close] all [sqlite3_blob | BLOBs] 
-** associated with the [sqlite3] object prior
-** to attempting to close the [sqlite3] object.
+** Applications should [sqlite3_finalize | finalize] all [prepared statements]
+** and [sqlite3_blob_close | close] all [BLOB handles] associated with
+** the [sqlite3] object prior to attempting to close the object.
+** The [sqlite3_next_stmt()] interface can be used to locate all
+** [prepared statements] associated with a [database connection] if desired.
+** Typical code might look like this:
 **
-** <todo>What happens to pending transactions?  Are they
-** rolled back, or abandoned?</todo>
-**
-** INVARIANTS:
-**
-** {F12011} The [sqlite3_close()] interface destroys an [sqlite3] object
-**          allocated by a prior call to [sqlite3_open()],
-**          [sqlite3_open16()], or [sqlite3_open_v2()].
-**
-** {F12012} The [sqlite3_close()] function releases all memory used by the
-**          connection and closes all open files.
-**
-** {F12013} If the database connection contains
-**          [prepared statements] that have not been
-**          finalized by [sqlite3_finalize()], then [sqlite3_close()]
-**          returns [SQLITE_BUSY] and leaves the connection open.
-**
-** {F12014} Giving sqlite3_close() a NULL pointer is a harmless no-op.
+** <blockquote><pre>
+** sqlite3_stmt *pStmt;
+** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
+** &nbsp;   sqlite3_finalize(pStmt);
+** }
+** </pre></blockquote>
 **
-** LIMITATIONS:
+** If [sqlite3_close()] is invoked while a transaction is open,
+** the transaction is automatically rolled back.
 **
-** {U12015} The parameter to [sqlite3_close()] must be an [sqlite3] object
-**          pointer previously obtained from [sqlite3_open()] or the 
-**          equivalent, or NULL.
+** The C parameter to [sqlite3_close(C)] must be either a NULL
+** pointer or an [sqlite3] object pointer obtained
+** from [sqlite3_open()], [sqlite3_open16()], or
+** [sqlite3_open_v2()], and not previously closed.
 **
-** {U12016} The parameter to [sqlite3_close()] must not have been previously
-**          closed.
+** Requirements:
+** [H12011] [H12012] [H12013] [H12014] [H12015] [H12019]
 */
 SQLITE_API int sqlite3_close(sqlite3 *);
 
@@ -671,115 +812,67 @@ SQLITE_API int sqlite3_close(sqlite3 *);
 typedef int (*sqlite3_callback)(void*,int,char**, char**);
 
 /*
-** CAPI3REF: One-Step Query Execution Interface {F12100}
+** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
 **
-** The sqlite3_exec() interface is a convenient way of running
-** one or more SQL statements without a lot of C code.  The
-** SQL statements are passed in as the second parameter to
-** sqlite3_exec().  The statements are evaluated one by one
-** until either an error or an interrupt is encountered or
-** until they are all done.  The 3rd parameter is an optional
-** callback that is invoked once for each row of any query results
-** produced by the SQL statements.  The 5th parameter tells where
+** The sqlite3_exec() interface is a convenient way of running one or more
+** SQL statements without having to write a lot of C code.  The UTF-8 encoded
+** SQL statements are passed in as the second parameter to sqlite3_exec().
+** The statements are evaluated one by one until either an error or
+** an interrupt is encountered, or until they are all done.  The 3rd parameter
+** is an optional callback that is invoked once for each row of any query
+** results produced by the SQL statements.  The 5th parameter tells where
 ** to write any error messages.
 **
+** The error message passed back through the 5th parameter is held
+** in memory obtained from [sqlite3_malloc()].  To avoid a memory leak,
+** the calling application should call [sqlite3_free()] on any error
+** message returned through the 5th parameter when it has finished using
+** the error message.
+**
+** If the SQL statement in the 2nd parameter is NULL or an empty string
+** or a string containing only whitespace and comments, then no SQL
+** statements are evaluated and the database is not changed.
+**
 ** The sqlite3_exec() interface is implemented in terms of
 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
-** The sqlite3_exec() routine does nothing that cannot be done
+** The sqlite3_exec() routine does nothing to the database that cannot be done
 ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
-** The sqlite3_exec() is just a convenient wrapper.
-**
-** INVARIANTS:
-** 
-** {F12101} The [sqlite3_exec()] interface evaluates zero or more UTF-8
-**          encoded, semicolon-separated, SQL statements in the
-**          zero-terminated string of its 2nd parameter within the
-**          context of the [sqlite3] object given in the 1st parameter.
-**
-** {F12104} The return value of [sqlite3_exec()] is SQLITE_OK if all
-**          SQL statements run successfully.
-**
-** {F12105} The return value of [sqlite3_exec()] is an appropriate 
-**          non-zero error code if any SQL statement fails.
-**
-** {F12107} If one or more of the SQL statements handed to [sqlite3_exec()]
-**          return results and the 3rd parameter is not NULL, then
-**          the callback function specified by the 3rd parameter is
-**          invoked once for each row of result.
-**
-** {F12110} If the callback returns a non-zero value then [sqlite3_exec()]
-**          will aborted the SQL statement it is currently evaluating,
-**          skip all subsequent SQL statements, and return [SQLITE_ABORT].
-**          <todo>What happens to *errmsg here?  Does the result code for
-**          sqlite3_errcode() get set?</todo>
-**
-** {F12113} The [sqlite3_exec()] routine will pass its 4th parameter through
-**          as the 1st parameter of the callback.
-**
-** {F12116} The [sqlite3_exec()] routine sets the 2nd parameter of its
-**          callback to be the number of columns in the current row of
-**          result.
-**
-** {F12119} The [sqlite3_exec()] routine sets the 3rd parameter of its 
-**          callback to be an array of pointers to strings holding the
-**          values for each column in the current result set row as
-**          obtained from [sqlite3_column_text()].
-**
-** {F12122} The [sqlite3_exec()] routine sets the 4th parameter of its
-**          callback to be an array of pointers to strings holding the
-**          names of result columns as obtained from [sqlite3_column_name()].
-**
-** {F12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
-**          [sqlite3_exec()] never invokes a callback.  All query
-**          results are silently discarded.
-**
-** {F12128} If an error occurs while parsing or evaluating any of the SQL
-**          statements handed to [sqlite3_exec()] then [sqlite3_exec()] will
-**          return an [error code] other than [SQLITE_OK].
-**
-** {F12131} If an error occurs while parsing or evaluating any of the SQL
-**          handed to [sqlite3_exec()] and if the 5th parameter (errmsg)
-**          to [sqlite3_exec()] is not NULL, then an error message is
-**          allocated using the equivalent of [sqlite3_mprintf()] and
-**          *errmsg is made to point to that message.
-**
-** {F12134} The [sqlite3_exec()] routine does not change the value of
-**          *errmsg if errmsg is NULL or if there are no errors.
 **
-** {F12137} The [sqlite3_exec()] function sets the error code and message
-**          accessible via [sqlite3_errcode()], [sqlite3_errmsg()], and
-**          [sqlite3_errmsg16()].
+** The first parameter to [sqlite3_exec()] must be an valid and open
+** [database connection].
 **
-** LIMITATIONS:
+** The database connection must not be closed while
+** [sqlite3_exec()] is running.
 **
-** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open
-**          [database connection].
+** The calling function should use [sqlite3_free()] to free
+** the memory that *errmsg is left pointing at once the error
+** message is no longer needed.
 **
-** {U12142} The database connection must not be closed while
-**          [sqlite3_exec()] is running.
-** 
-** {U12143} The calling function is should use [sqlite3_free()] to free
-**          the memory that *errmsg is left pointing at once the error
-**          message is no longer needed.
+** The SQL statement text in the 2nd parameter to [sqlite3_exec()]
+** must remain unchanged while [sqlite3_exec()] is running.
 **
-** {U12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
-**          must remain unchanged while [sqlite3_exec()] is running.
+** Requirements:
+** [H12101] [H12102] [H12104] [H12105] [H12107] [H12110] [H12113] [H12116]
+** [H12119] [H12122] [H12125] [H12131] [H12134] [H12137] [H12138]
 */
 SQLITE_API int sqlite3_exec(
   sqlite3*,                                  /* An open database */
-  const char *sql,                           /* SQL to be evaluted */
+  const char *sql,                           /* SQL to be evaluated */
   int (*callback)(void*,int,char**,char**),  /* Callback function */
   void *,                                    /* 1st argument to callback */
   char **errmsg                              /* Error msg written here */
 );
 
 /*
-** CAPI3REF: Result Codes {F10210}
+** CAPI3REF: Result Codes {H10210} <S10700>
 ** KEYWORDS: SQLITE_OK {error code} {error codes}
+** KEYWORDS: {result code} {result codes}
 **
 ** Many SQLite functions return an integer result code from the set shown
 ** here in order to indicates success or failure.
 **
+** New error codes may be added in future versions of SQLite.
+**
 ** See also: [SQLITE_IOERR_READ | extended result codes]
 */
 #define SQLITE_OK           0   /* Successful result */
@@ -815,20 +908,20 @@ SQLITE_API int sqlite3_exec(
 /* end-of-error-codes */
 
 /*
-** CAPI3REF: Extended Result Codes {F10220}
+** CAPI3REF: Extended Result Codes {H10220} <S10700>
 ** KEYWORDS: {extended error code} {extended error codes}
-** KEYWORDS: {extended result codes}
+** KEYWORDS: {extended result code} {extended result codes}
 **
 ** In its default configuration, SQLite API routines return one of 26 integer
-** [SQLITE_OK | result codes].  However, experience has shown that
-** many of these result codes are too course-grained.  They do not provide as
+** [SQLITE_OK | result codes].  However, experience has shown that many of
+** these result codes are too coarse-grained.  They do not provide as
 ** much information about problems as programmers might like.  In an effort to
 ** address this, newer versions of SQLite (version 3.3.8 and later) include
 ** support for additional result codes that provide more detailed information
 ** about errors. The extended result codes are enabled or disabled
-** for each database connection using the [sqlite3_extended_result_codes()]
-** API.
-** 
+** on a per database connection basis using the
+** [sqlite3_extended_result_codes()] API.
+**
 ** Some of the available extended result codes are listed here.
 ** One may expect the number of extended result codes will be expand
 ** over time.  Software that uses extended result codes should expect
@@ -836,56 +929,53 @@ SQLITE_API int sqlite3_exec(
 **
 ** The SQLITE_OK result code will never be extended.  It will always
 ** be exactly zero.
-** 
-** INVARIANTS:
-**
-** {F10223} The symbolic name for an extended result code always contains
-**          a related primary result code as a prefix.
-**
-** {F10224} Primary result code names contain a single "_" character.
-**
-** {F10225} Extended result code names contain two or more "_" characters.
-**
-** {F10226} The numeric value of an extended result code contains the
-**          numeric value of its corresponding primary result code in
-**          its least significant 8 bits.
 */
-#define SQLITE_IOERR_READ          (SQLITE_IOERR | (1<<8))
-#define SQLITE_IOERR_SHORT_READ    (SQLITE_IOERR | (2<<8))
-#define SQLITE_IOERR_WRITE         (SQLITE_IOERR | (3<<8))
-#define SQLITE_IOERR_FSYNC         (SQLITE_IOERR | (4<<8))
-#define SQLITE_IOERR_DIR_FSYNC     (SQLITE_IOERR | (5<<8))
-#define SQLITE_IOERR_TRUNCATE      (SQLITE_IOERR | (6<<8))
-#define SQLITE_IOERR_FSTAT         (SQLITE_IOERR | (7<<8))
-#define SQLITE_IOERR_UNLOCK        (SQLITE_IOERR | (8<<8))
-#define SQLITE_IOERR_RDLOCK        (SQLITE_IOERR | (9<<8))
-#define SQLITE_IOERR_DELETE        (SQLITE_IOERR | (10<<8))
-#define SQLITE_IOERR_BLOCKED       (SQLITE_IOERR | (11<<8))
-#define SQLITE_IOERR_NOMEM         (SQLITE_IOERR | (12<<8))
-
-/*
-** CAPI3REF: Flags For File Open Operations {F10230}
+#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
+#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
+#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
+#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
+#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
+#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
+#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
+#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
+#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
+#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
+#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
+#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
+#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
+#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
+#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
+#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
+#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED | (1<<8) )
+
+/*
+** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
 **
 ** These bit values are intended for use in the
 ** 3rd parameter to the [sqlite3_open_v2()] interface and
 ** in the 4th parameter to the xOpen method of the
 ** [sqlite3_vfs] object.
 */
-#define SQLITE_OPEN_READONLY         0x00000001
-#define SQLITE_OPEN_READWRITE        0x00000002
-#define SQLITE_OPEN_CREATE           0x00000004
-#define SQLITE_OPEN_DELETEONCLOSE    0x00000008
-#define SQLITE_OPEN_EXCLUSIVE        0x00000010
-#define SQLITE_OPEN_MAIN_DB          0x00000100
-#define SQLITE_OPEN_TEMP_DB          0x00000200
-#define SQLITE_OPEN_TRANSIENT_DB     0x00000400
-#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800
-#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000
-#define SQLITE_OPEN_SUBJOURNAL       0x00002000
-#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000
-
-/*
-** CAPI3REF: Device Characteristics {F10240}
+#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
+#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
+#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
+#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
+#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
+#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
+#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
+#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
+#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
+#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
+
+/*
+** CAPI3REF: Device Characteristics {H10240} <H11120>
 **
 ** The xDeviceCapabilities method of the [sqlite3_io_methods]
 ** object returns an integer which is a vector of the these
@@ -917,7 +1007,7 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_IOCAP_SEQUENTIAL      0x00000400
 
 /*
-** CAPI3REF: File Locking Levels {F10250}
+** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
 **
 ** SQLite uses one of these integer values as the second
 ** argument to calls it makes to the xLock() and xUnlock() methods
@@ -930,7 +1020,7 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_LOCK_EXCLUSIVE     4
 
 /*
-** CAPI3REF: Synchronization Type Flags {F10260}
+** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
 **
 ** When SQLite invokes the xSync() method of an
 ** [sqlite3_io_methods] object it uses a combination of
@@ -938,20 +1028,21 @@ SQLITE_API int sqlite3_exec(
 **
 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
 ** sync operation only needs to flush data to mass storage.  Inode
-** information need not be flushed. The SQLITE_SYNC_NORMAL flag means 
-** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means 
-** to use Mac OS-X style fullsync instead of fsync().
+** information need not be flushed. If the lower four bits of the flag
+** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
+** If the lower four bits equal SQLITE_SYNC_FULL, that means
+** to use Mac OS X style fullsync instead of fsync().
 */
 #define SQLITE_SYNC_NORMAL        0x00002
 #define SQLITE_SYNC_FULL          0x00003
 #define SQLITE_SYNC_DATAONLY      0x00010
 
-
 /*
-** CAPI3REF: OS Interface Open File Handle {F11110}
+** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
 **
-** An [sqlite3_file] object represents an open file in the OS
-** interface layer.  Individual OS interface implementations will
+** An [sqlite3_file] object represents an open file in the 
+** [sqlite3_vfs | OS interface layer].  Individual OS interface
+** implementations will
 ** want to subclass this object by appending additional fields
 ** for their own use.  The pMethods entry is a pointer to an
 ** [sqlite3_io_methods] object that defines methods for performing
@@ -963,19 +1054,26 @@ struct sqlite3_file {
 };
 
 /*
-** CAPI3REF: OS Interface File Virtual Methods Object {F11120}
+** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
 **
-** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to
-** an instance of this object.  This object defines the
-** methods used to perform various operations against the open file.
+** Every file opened by the [sqlite3_vfs] xOpen method populates an
+** [sqlite3_file] object (or, more commonly, a subclass of the
+** [sqlite3_file] object) with a pointer to an instance of this object.
+** This object defines the methods used to perform various operations
+** against the open file represented by the [sqlite3_file] object.
+**
+** If the xOpen method sets the sqlite3_file.pMethods element 
+** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
+** may be invoked even if the xOpen reported that it failed.  The
+** only way to prevent a call to xClose following a failed xOpen
+** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
 **
 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
 ** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
-*  The second choice is an
-** OS-X style fullsync.  The SQLITE_SYNC_DATA flag may be ORed in to
-** indicate that only the data of the file and not its inode needs to be
-** synced.
-** 
+** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
+** flag may be ORed in to indicate that only the data of the file
+** and not its inode needs to be synced.
+**
 ** The integer values to xLock() and xUnlock() are one of
 ** <ul>
 ** <li> [SQLITE_LOCK_NONE],
@@ -984,26 +1082,24 @@ struct sqlite3_file {
 ** <li> [SQLITE_LOCK_PENDING], or
 ** <li> [SQLITE_LOCK_EXCLUSIVE].
 ** </ul>
-** xLock() increases the lock. xUnlock() decreases the lock.  
-** The xCheckReservedLock() method looks
-** to see if any database connection, either in this
-** process or in some other process, is holding an RESERVED,
+** xLock() increases the lock. xUnlock() decreases the lock.
+** The xCheckReservedLock() method checks whether any database connection,
+** either in this process or in some other process, is holding a RESERVED,
 ** PENDING, or EXCLUSIVE lock on the file.  It returns true
-** if such a lock exists and false if not.
-** 
+** if such a lock exists and false otherwise.
+**
 ** The xFileControl() method is a generic interface that allows custom
 ** VFS implementations to directly control an open file using the
-** [sqlite3_file_control()] interface.  The second "op" argument
-** is an integer opcode.   The third
-** argument is a generic pointer which is intended to be a pointer
-** to a structure that may contain arguments or space in which to
+** [sqlite3_file_control()] interface.  The second "op" argument is an
+** integer opcode.  The third argument is a generic pointer intended to
+** point to a structure that may contain arguments or space in which to
 ** write return values.  Potential uses for xFileControl() might be
 ** functions to enable blocking locks with timeouts, to change the
 ** locking strategy (for example to use dot-file locks), to inquire
 ** about the status of a lock, or to break stale locks.  The SQLite
-** core reserves opcodes less than 100 for its own use. 
+** core reserves all opcodes less than 100 for its own use.
 ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
-** Applications that define a custom xFileControl method should use opcodes 
+** Applications that define a custom xFileControl method should use opcodes
 ** greater than 100 to avoid conflicts.
 **
 ** The xSectorSize() method returns the sector size of the
@@ -1037,6 +1133,12 @@ struct sqlite3_file {
 ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
 ** information is written to disk in the same order as calls
 ** to xWrite().
+**
+** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
+** in the unread portions of the buffer with zeros.  A VFS that
+** fails to zero-fill short reads might seem to work.  However,
+** failure to zero-fill short reads will eventually lead to
+** database corruption.
 */
 typedef struct sqlite3_io_methods sqlite3_io_methods;
 struct sqlite3_io_methods {
@@ -1049,7 +1151,7 @@ struct sqlite3_io_methods {
   int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
   int (*xLock)(sqlite3_file*, int);
   int (*xUnlock)(sqlite3_file*, int);
-  int (*xCheckReservedLock)(sqlite3_file*);
+  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
   int (*xFileControl)(sqlite3_file*, int op, void *pArg);
   int (*xSectorSize)(sqlite3_file*);
   int (*xDeviceCharacteristics)(sqlite3_file*);
@@ -1057,10 +1159,10 @@ struct sqlite3_io_methods {
 };
 
 /*
-** CAPI3REF: Standard File Control Opcodes {F11310}
+** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
 **
 ** These integer constants are opcodes for the xFileControl method
-** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()]
+** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
 ** interface.
 **
 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
@@ -1072,9 +1174,12 @@ struct sqlite3_io_methods {
 ** is defined.
 */
 #define SQLITE_FCNTL_LOCKSTATE        1
+#define SQLITE_GET_LOCKPROXYFILE      2
+#define SQLITE_SET_LOCKPROXYFILE      3
+#define SQLITE_LAST_ERRNO             4
 
 /*
-** CAPI3REF: Mutex Handle {F17110}
+** CAPI3REF: Mutex Handle {H17110} <S20130>
 **
 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
 ** abstract type for a mutex object.  The SQLite core never looks
@@ -1086,15 +1191,18 @@ struct sqlite3_io_methods {
 typedef struct sqlite3_mutex sqlite3_mutex;
 
 /*
-** CAPI3REF: OS Interface Object {F11140}
+** CAPI3REF: OS Interface Object {H11140} <S20100>
 **
-** An instance of this object defines the interface between the
-** SQLite core and the underlying operating system.  The "vfs"
+** An instance of the sqlite3_vfs object defines the interface between
+** the SQLite core and the underlying operating system.  The "vfs"
 ** in the name of the object stands for "virtual file system".
 **
-** The iVersion field is initially 1 but may be larger for future
-** versions of SQLite.  Additional fields may be appended to this
-** object when the iVersion value is increased.
+** The value of the iVersion field is initially 1 but may be larger in
+** future versions of SQLite.  Additional fields may be appended to this
+** object when the iVersion value is increased.  Note that the structure
+** of the sqlite3_vfs object changes in the transaction between
+** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
+** modified.
 **
 ** The szOsFile field is the size of the subclassed [sqlite3_file]
 ** structure used by this VFS.  mxPathname is the maximum length of
@@ -1104,9 +1212,10 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** the pNext pointer.  The [sqlite3_vfs_register()]
 ** and [sqlite3_vfs_unregister()] interfaces manage this list
 ** in a thread-safe way.  The [sqlite3_vfs_find()] interface
-** searches the list.
+** searches the list.  Neither the application code nor the VFS
+** implementation should use the pNext pointer.
 **
-** The pNext field is the only field in the sqlite3_vfs 
+** The pNext field is the only field in the sqlite3_vfs
 ** structure that SQLite will ever modify.  SQLite will only access
 ** or modify this field while holding a particular static mutex.
 ** The application should never modify anything within the sqlite3_vfs
@@ -1115,23 +1224,28 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** The zName field holds the name of the VFS module.  The name must
 ** be unique across all VFS modules.
 **
-** {F11141} SQLite will guarantee that the zFilename string passed to
-** xOpen() is a full pathname as generated by xFullPathname() and
-** that the string will be valid and unchanged until xClose() is
-** called.  {END} So the [sqlite3_file] can store a pointer to the
+** SQLite will guarantee that the zFilename parameter to xOpen
+** is either a NULL pointer or string obtained
+** from xFullPathname().  SQLite further guarantees that
+** the string will be valid and unchanged until xClose() is
+** called. Because of the previous sentence,
+** the [sqlite3_file] can safely store a pointer to the
 ** filename if it needs to remember the filename for some reason.
+** If the zFilename parameter is xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  Whenever the 
+** xFilename parameter is NULL it will also be the case that the
+** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
 **
-** {F11142} The flags argument to xOpen() includes all bits set in
+** The flags argument to xOpen() includes all bits set in
 ** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
 ** or [sqlite3_open16()] is used, then flags includes at least
-** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END}
+** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
 ** If xOpen() opens a file read-only then it sets *pOutFlags to
-** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be
-** set.
-** 
-** {F11143} SQLite will also add one of the following flags to the xOpen()
+** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
+**
+** SQLite will also add one of the following flags to the xOpen()
 ** call, depending on the object being opened:
-** 
+**
 ** <ul>
 ** <li>  [SQLITE_OPEN_MAIN_DB]
 ** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
@@ -1140,62 +1254,70 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
-** </ul> {END}
+** </ul>
 **
 ** The file I/O implementation can use the object type flags to
-** changes the way it deals with files.  For example, an application
+** change the way it deals with files.  For example, an application
 ** that does not care about crash recovery or rollback might make
 ** the open of a journal file a no-op.  Writes to this journal would
-** also be no-ops, and any attempt to read the journal would return 
-** SQLITE_IOERR.  Or the implementation might recognize that a database 
-** file will be doing page-aligned sector reads and writes in a random 
+** also be no-ops, and any attempt to read the journal would return
+** SQLITE_IOERR.  Or the implementation might recognize that a database
+** file will be doing page-aligned sector reads and writes in a random
 ** order and set up its I/O subsystem accordingly.
-** 
-** SQLite might also add one of the following flags to the xOpen
-** method:
-** 
+**
+** SQLite might also add one of the following flags to the xOpen method:
+**
 ** <ul>
 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
 ** <li> [SQLITE_OPEN_EXCLUSIVE]
 ** </ul>
-** 
-** {F11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
-** deleted when it is closed.  {F11146} The [SQLITE_OPEN_DELETEONCLOSE]
-** will be set for TEMP  databases, journals and for subjournals. 
-** {F11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
-** for exclusive access.  This flag is set for all files except
-** for the main database file. {END}
-** 
-** {F11148} At least szOsFile bytes of memory are allocated by SQLite 
-** to hold the  [sqlite3_file] structure passed as the third 
-** argument to xOpen.  {END}  The xOpen method does not have to
-** allocate the structure; it should just fill it in.
-** 
-** {F11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 
-** to test for the existance of a file,
-** or [SQLITE_ACCESS_READWRITE] to test to see
-** if a file is readable and writable, or [SQLITE_ACCESS_READ]
-** to test to see if a file is at least readable.  {END} The file can be a 
+**
+** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
+** deleted when it is closed.  The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP  databases, journals and for subjournals.
+**
+** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** with the [SQLITE_OPEN_CREATE] flag, which are both directly
+** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
+** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
+** SQLITE_OPEN_CREATE, is used to indicate that file should always
+** be created, and that it is an error if it already exists.
+** It is <i>not</i> used to indicate the file should be opened 
+** for exclusive access.
+**
+** At least szOsFile bytes of memory are allocated by SQLite
+** to hold the  [sqlite3_file] structure passed as the third
+** argument to xOpen.  The xOpen method does not have to
+** allocate the structure; it should just fill it in.  Note that
+** the xOpen method must set the sqlite3_file.pMethods to either
+** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
+** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
+** element will be valid after xOpen returns regardless of the success
+** or failure of the xOpen call.
+**
+** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
+** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
+** to test whether a file is at least readable.   The file can be a
 ** directory.
-** 
-** {F11150} SQLite will always allocate at least mxPathname+1 bytes for
-** the output buffers for xGetTempname and xFullPathname. {F11151} The exact
-** size of the output buffer is also passed as a parameter to both 
-** methods. {END} If the output buffer is not large enough, SQLITE_CANTOPEN
-** should be returned. As this is handled as a fatal error by SQLite,
-** vfs implementations should endeavor to prevent this by setting 
-** mxPathname to a sufficiently large value.
-** 
+**
+** SQLite will always allocate at least mxPathname+1 bytes for the
+** output buffer xFullPathname.  The exact size of the output buffer
+** is also passed as a parameter to both  methods. If the output buffer
+** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
+** handled as a fatal error by SQLite, vfs implementations should endeavor
+** to prevent this by setting mxPathname to a sufficiently large value.
+**
 ** The xRandomness(), xSleep(), and xCurrentTime() interfaces
 ** are not strictly a part of the filesystem, but they are
 ** included in the VFS structure for completeness.
 ** The xRandomness() function attempts to return nBytes bytes
 ** of good-quality randomness into zOut.  The return value is
-** the actual number of bytes of randomness obtained.  The
-** xSleep() method causes the calling thread to sleep for at
+** the actual number of bytes of randomness obtained.
+** The xSleep() method causes the calling thread to sleep for at
 ** least the number of microseconds given.  The xCurrentTime()
-** method returns a Julian Day Number for the current date and
-** time.
+** method returns a Julian Day Number for the current date and time.
+**
 */
 typedef struct sqlite3_vfs sqlite3_vfs;
 struct sqlite3_vfs {
@@ -1208,134 +1330,540 @@ struct sqlite3_vfs {
   int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
                int flags, int *pOutFlags);
   int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
-  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
-  int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut);
+  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
   int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
   void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
   void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
-  void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
+  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
   void (*xDlClose)(sqlite3_vfs*, void*);
   int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
   int (*xSleep)(sqlite3_vfs*, int microseconds);
   int (*xCurrentTime)(sqlite3_vfs*, double*);
+  int (*xGetLastError)(sqlite3_vfs*, int, char *);
   /* New fields may be appended in figure versions.  The iVersion
   ** value will increment whenever this happens. */
 };
 
 /*
-** CAPI3REF: Flags for the xAccess VFS method {F11190}
+** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
 **
-** {F11191} These integer constants can be used as the third parameter to
+** These integer constants can be used as the third parameter to
 ** the xAccess method of an [sqlite3_vfs] object. {END}  They determine
-** what kind of permissions the xAccess method is
-** looking for.  {F11192} With SQLITE_ACCESS_EXISTS, the xAccess method
-** simply checks to see if the file exists. {F11193} With
-** SQLITE_ACCESS_READWRITE, the xAccess method checks to see
-** if the file is both readable and writable.  {F11194} With
-** SQLITE_ACCESS_READ the xAccess method
-** checks to see if the file is readable.
+** what kind of permissions the xAccess method is looking for.
+** With SQLITE_ACCESS_EXISTS, the xAccess method
+** simply checks whether the file exists.
+** With SQLITE_ACCESS_READWRITE, the xAccess method
+** checks whether the file is both readable and writable.
+** With SQLITE_ACCESS_READ, the xAccess method
+** checks whether the file is readable.
 */
 #define SQLITE_ACCESS_EXISTS    0
 #define SQLITE_ACCESS_READWRITE 1
 #define SQLITE_ACCESS_READ      2
 
 /*
-** CAPI3REF: Enable Or Disable Extended Result Codes {F12200}
+** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
+**
+** The sqlite3_initialize() routine initializes the
+** SQLite library.  The sqlite3_shutdown() routine
+** deallocates any resources that were allocated by sqlite3_initialize().
+**
+** A call to sqlite3_initialize() is an "effective" call if it is
+** the first time sqlite3_initialize() is invoked during the lifetime of
+** the process, or if it is the first time sqlite3_initialize() is invoked
+** following a call to sqlite3_shutdown().  Only an effective call
+** of sqlite3_initialize() does any initialization.  All other calls
+** are harmless no-ops.
+**
+** A call to sqlite3_shutdown() is an "effective" call if it is the first
+** call to sqlite3_shutdown() since the last sqlite3_initialize().  Only
+** an effective call to sqlite3_shutdown() does any deinitialization.
+** All other calls to sqlite3_shutdown() are harmless no-ops.
+**
+** Among other things, sqlite3_initialize() shall invoke
+** sqlite3_os_init().  Similarly, sqlite3_shutdown()
+** shall invoke sqlite3_os_end().
+**
+** The sqlite3_initialize() routine returns [SQLITE_OK] on success.
+** If for some reason, sqlite3_initialize() is unable to initialize
+** the library (perhaps it is unable to allocate a needed resource such
+** as a mutex) it returns an [error code] other than [SQLITE_OK].
+**
+** The sqlite3_initialize() routine is called internally by many other
+** SQLite interfaces so that an application usually does not need to
+** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
+** calls sqlite3_initialize() so the SQLite library will be automatically
+** initialized when [sqlite3_open()] is called if it has not be initialized
+** already.  However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
+** compile-time option, then the automatic calls to sqlite3_initialize()
+** are omitted and the application must call sqlite3_initialize() directly
+** prior to using any other SQLite interface.  For maximum portability,
+** it is recommended that applications always invoke sqlite3_initialize()
+** directly prior to using any other SQLite interface.  Future releases
+** of SQLite may require this.  In other words, the behavior exhibited
+** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
+** default behavior in some future release of SQLite.
+**
+** The sqlite3_os_init() routine does operating-system specific
+** initialization of the SQLite library.  The sqlite3_os_end()
+** routine undoes the effect of sqlite3_os_init().  Typical tasks
+** performed by these routines include allocation or deallocation
+** of static resources, initialization of global variables,
+** setting up a default [sqlite3_vfs] module, or setting up
+** a default configuration using [sqlite3_config()].
+**
+** The application should never invoke either sqlite3_os_init()
+** or sqlite3_os_end() directly.  The application should only invoke
+** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
+** interface is called automatically by sqlite3_initialize() and
+** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
+** implementations for sqlite3_os_init() and sqlite3_os_end()
+** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
+** When [custom builds | built for other platforms]
+** (using the [SQLITE_OS_OTHER=1] compile-time
+** option) the application must supply a suitable implementation for
+** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
+** implementation of sqlite3_os_init() or sqlite3_os_end()
+** must return [SQLITE_OK] on success and some other [error code] upon
+** failure.
+*/
+SQLITE_API int sqlite3_initialize(void);
+SQLITE_API int sqlite3_shutdown(void);
+SQLITE_API int sqlite3_os_init(void);
+SQLITE_API int sqlite3_os_end(void);
+
+/*
+** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
+** EXPERIMENTAL
+**
+** The sqlite3_config() interface is used to make global configuration
+** changes to SQLite in order to tune SQLite to the specific needs of
+** the application.  The default configuration is recommended for most
+** applications and so this routine is usually not necessary.  It is
+** provided to support rare applications with unusual needs.
+**
+** The sqlite3_config() interface is not threadsafe.  The application
+** must insure that no other SQLite interfaces are invoked by other
+** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** Note, however, that sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
+** The first argument to sqlite3_config() is an integer
+** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
+** what property of SQLite is to be configured.  Subsequent arguments
+** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
+** in the first argument.
+**
+** When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
+** If the option is unknown or SQLite is unable to set the option
+** then this routine returns a non-zero [error code].
+**
+** Requirements:
+** [H14103] [H14106] [H14120] [H14123] [H14126] [H14129] [H14132] [H14135]
+** [H14138] [H14141] [H14144] [H14147] [H14150] [H14153] [H14156] [H14159]
+** [H14162] [H14165] [H14168]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);
+
+/*
+** CAPI3REF: Configure database connections  {H14200} <S20000>
+** EXPERIMENTAL
+**
+** The sqlite3_db_config() interface is used to make configuration
+** changes to a [database connection].  The interface is similar to
+** [sqlite3_config()] except that the changes apply to a single
+** [database connection] (specified in the first argument).  The
+** sqlite3_db_config() interface can only be used immediately after
+** the database connection is created using [sqlite3_open()],
+** [sqlite3_open16()], or [sqlite3_open_v2()].  
+**
+** The second argument to sqlite3_db_config(D,V,...)  is the
+** configuration verb - an integer code that indicates what
+** aspect of the [database connection] is being configured.
+** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
+** New verbs are likely to be added in future releases of SQLite.
+** Additional arguments depend on the verb.
+**
+** Requirements:
+** [H14203] [H14206] [H14209] [H14212] [H14215]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
+** EXPERIMENTAL
+**
+** An instance of this object defines the interface between SQLite
+** and low-level memory allocation routines.
+**
+** This object is used in only one place in the SQLite interface.
+** A pointer to an instance of this object is the argument to
+** [sqlite3_config()] when the configuration option is
+** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
+** By creating an instance of this object
+** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
+** during configuration, an application can specify an alternative
+** memory allocation subsystem for SQLite to use for all of its
+** dynamic memory needs.
+**
+** Note that SQLite comes with several [built-in memory allocators]
+** that are perfectly adequate for the overwhelming majority of applications
+** and that this object is only useful to a tiny minority of applications
+** with specialized memory allocation requirements.  This object is
+** also used during testing of SQLite in order to specify an alternative
+** memory allocator that simulates memory out-of-memory conditions in
+** order to verify that SQLite recovers gracefully from such
+** conditions.
+**
+** The xMalloc and xFree methods must work like the
+** malloc() and free() functions from the standard C library.
+** The xRealloc method must work like realloc() from the standard C library
+** with the exception that if the second argument to xRealloc is zero,
+** xRealloc must be a no-op - it must not perform any allocation or
+** deallocation.  SQLite guaranteeds that the second argument to
+** xRealloc is always a value returned by a prior call to xRoundup.
+** And so in cases where xRoundup always returns a positive number,
+** xRealloc can perform exactly as the standard library realloc() and
+** still be in compliance with this specification.
+**
+** xSize should return the allocated size of a memory allocation
+** previously obtained from xMalloc or xRealloc.  The allocated size
+** is always at least as big as the requested size but may be larger.
+**
+** The xRoundup method returns what would be the allocated size of
+** a memory allocation given a particular requested size.  Most memory
+** allocators round up memory allocations at least to the next multiple
+** of 8.  Some allocators round up to a larger multiple or to a power of 2.
+** Every memory allocation request coming in through [sqlite3_malloc()]
+** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
+** that causes the corresponding memory allocation to fail.
+**
+** The xInit method initializes the memory allocator.  (For example,
+** it might allocate any require mutexes or initialize internal data
+** structures.  The xShutdown method is invoked (indirectly) by
+** [sqlite3_shutdown()] and should deallocate any resources acquired
+** by xInit.  The pAppData pointer is used as the only parameter to
+** xInit and xShutdown.
+**
+** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe.  The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  For all other methods, SQLite
+** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
+** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
+** it is by default) and so the methods are automatically serialized.
+** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
+** methods must be threadsafe or else make their own arrangements for
+** serialization.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+*/
+typedef struct sqlite3_mem_methods sqlite3_mem_methods;
+struct sqlite3_mem_methods {
+  void *(*xMalloc)(int);         /* Memory allocation function */
+  void (*xFree)(void*);          /* Free a prior allocation */
+  void *(*xRealloc)(void*,int);  /* Resize an allocation */
+  int (*xSize)(void*);           /* Return the size of an allocation */
+  int (*xRoundup)(int);          /* Round up request size to allocation size */
+  int (*xInit)(void*);           /* Initialize the memory allocator */
+  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
+  void *pAppData;                /* Argument to xInit() and xShutdown() */
+};
+
+/*
+** CAPI3REF: Configuration Options {H10160} <S20000>
+** EXPERIMENTAL
 **
-** The sqlite3_extended_result_codes() routine enables or disables the
-** [SQLITE_IOERR_READ | extended result codes] feature of SQLite.
-** The extended result codes are disabled by default for historical
-** compatibility.
+** These constants are the available integer configuration options that
+** can be passed as the first argument to the [sqlite3_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_config()] to make sure that
+** the call worked.  The [sqlite3_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
+** <dd>There are no arguments to this option.  This option disables
+** all mutexing and puts SQLite into a mode where it can only be used
+** by a single thread.</dd>
+**
+** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
+** <dd>There are no arguments to this option.  This option disables
+** mutexing on [database connection] and [prepared statement] objects.
+** The application is responsible for serializing access to
+** [database connections] and [prepared statements].  But other mutexes
+** are enabled so that SQLite will be safe to use in a multi-threaded
+** environment as long as no two threads attempt to use the same
+** [database connection] at the same time.  See the [threading mode]
+** documentation for additional information.</dd>
+**
+** <dt>SQLITE_CONFIG_SERIALIZED</dt>
+** <dd>There are no arguments to this option.  This option enables
+** all mutexes including the recursive
+** mutexes on [database connection] and [prepared statement] objects.
+** In this mode (which is the default when SQLite is compiled with
+** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
+** to [database connections] and [prepared statements] so that the
+** application is free to use the same [database connection] or the
+** same [prepared statement] in different threads at the same time.
+** See the [threading mode] documentation for additional information.</dd>
+**
+** <dt>SQLITE_CONFIG_MALLOC</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The argument specifies
+** alternative low-level memory allocation routines to be used in place of
+** the memory allocation routines built into SQLite.</dd>
+**
+** <dt>SQLITE_CONFIG_GETMALLOC</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
+** structure is filled with the currently defined memory allocation routines.
+** This option can be used to overload the default memory allocation
+** routines with a wrapper that simulations memory allocation failure or
+** tracks memory usage, for example.</dd>
+**
+** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
+** <dd>This option takes single argument of type int, interpreted as a 
+** boolean, which enables or disables the collection of memory allocation 
+** statistics. When disabled, the following SQLite interfaces become 
+** non-operational:
+**   <ul>
+**   <li> [sqlite3_memory_used()]
+**   <li> [sqlite3_memory_highwater()]
+**   <li> [sqlite3_soft_heap_limit()]
+**   <li> [sqlite3_status()]
+**   </ul>
+** </dd>
+**
+** <dt>SQLITE_CONFIG_SCRATCH</dt>
+** <dd>This option specifies a static memory buffer that SQLite can use for
+** scratch memory.  There are three arguments:  A pointer an 8-byte
+** aligned memory buffer from which the scrach allocations will be
+** drawn, the size of each scratch allocation (sz),
+** and the maximum number of scratch allocations (N).  The sz
+** argument must be a multiple of 16. The sz parameter should be a few bytes
+** larger than the actual scratch space required due to internal overhead.
+** The first argument should pointer to an 8-byte aligned buffer
+** of at least sz*N bytes of memory.
+** SQLite will use no more than one scratch buffer at once per thread, so
+** N should be set to the expected maximum number of threads.  The sz
+** parameter should be 6 times the size of the largest database page size.
+** Scratch buffers are used as part of the btree balance operation.  If
+** The btree balancer needs additional memory beyond what is provided by
+** scratch buffers or if no scratch buffer space is specified, then SQLite
+** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
+**
+** <dt>SQLITE_CONFIG_PAGECACHE</dt>
+** <dd>This option specifies a static memory buffer that SQLite can use for
+** the database page cache with the default page cache implemenation.  
+** This configuration should not be used if an application-define page
+** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
+** There are three arguments to this option: A pointer to 8-byte aligned
+** memory, the size of each page buffer (sz), and the number of pages (N).
+** The sz argument should be the size of the largest database page
+** (a power of two between 512 and 32768) plus a little extra for each
+** page header.  The page header size is 20 to 40 bytes depending on
+** the host architecture.  It is harmless, apart from the wasted memory,
+** to make sz a little too large.  The first
+** argument should point to an allocation of at least sz*N bytes of memory.
+** SQLite will use the memory provided by the first argument to satisfy its
+** memory needs for the first N pages that it adds to cache.  If additional
+** page cache memory is needed beyond what is provided by this option, then
+** SQLite goes to [sqlite3_malloc()] for the additional storage space.
+** The implementation might use one or more of the N buffers to hold 
+** memory accounting information. The pointer in the first argument must
+** be aligned to an 8-byte boundary or subsequent behavior of SQLite
+** will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_HEAP</dt>
+** <dd>This option specifies a static memory buffer that SQLite will use
+** for all of its dynamic memory allocation needs beyond those provided
+** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
+** There are three arguments: An 8-byte aligned pointer to the memory,
+** the number of bytes in the memory buffer, and the minimum allocation size.
+** If the first pointer (the memory pointer) is NULL, then SQLite reverts
+** to using its default memory allocator (the system malloc() implementation),
+** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  If the
+** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
+** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
+** allocator is engaged to handle all of SQLites memory allocation needs.
+** The first pointer (the memory pointer) must be aligned to an 8-byte
+** boundary or subsequent behavior of SQLite will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_MUTEX</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
+** alternative low-level mutex routines to be used in place
+** the mutex routines built into SQLite.</dd>
+**
+** <dt>SQLITE_CONFIG_GETMUTEX</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The
+** [sqlite3_mutex_methods]
+** structure is filled with the currently defined mutex routines.
+** This option can be used to overload the default mutex allocation
+** routines with a wrapper used to track mutex usage for performance
+** profiling or testing, for example.</dd>
+**
+** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
+** <dd>This option takes two arguments that determine the default
+** memory allocation lookaside optimization.  The first argument is the
+** size of each lookaside buffer slot and the second is the number of
+** slots allocated to each database connection.  This option sets the
+** <i>default</i> lookaside size.  The [SQLITE_DBCONFIG_LOOKASIDE]
+** verb to [sqlite3_db_config()] can be used to change the lookaside
+** configuration on individual connections.</dd>
+**
+** <dt>SQLITE_CONFIG_PCACHE</dt>
+** <dd>This option takes a single argument which is a pointer to
+** an [sqlite3_pcache_methods] object.  This object specifies the interface
+** to a custom page cache implementation.  SQLite makes a copy of the
+** object and uses it for page cache memory allocations.</dd>
+**
+** <dt>SQLITE_CONFIG_GETPCACHE</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** [sqlite3_pcache_methods] object.  SQLite copies of the current
+** page cache implementation into that object.</dd>
+**
+** </dl>
+*/
+#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
+#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
+#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
+#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
+#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
+#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
+#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
+#define SQLITE_CONFIG_PCACHE       14  /* sqlite3_pcache_methods* */
+#define SQLITE_CONFIG_GETPCACHE    15  /* sqlite3_pcache_methods* */
+
+/*
+** CAPI3REF: Configuration Options {H10170} <S20000>
+** EXPERIMENTAL
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked.  The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
+** <dd>This option takes three additional arguments that determine the 
+** [lookaside memory allocator] configuration for the [database connection].
+** The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to an memory buffer to use for lookaside memory.
+** The first argument may be NULL in which case SQLite will allocate the
+** lookaside buffer itself using [sqlite3_malloc()].  The second argument is the
+** size of each lookaside buffer slot and the third argument is the number of
+** slots.  The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments.  The buffer
+** must be aligned to an 8-byte boundary.  If the second argument is not
+** a multiple of 8, it is internally rounded down to the next smaller
+** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
 **
-** INVARIANTS:
+** </dl>
+*/
+#define SQLITE_DBCONFIG_LOOKASIDE    1001  /* void* int int */
+
+
+/*
+** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
 **
-** {F12201} Each new [database connection] has the 
-**          [extended result codes] feature
-**          disabled by default.
+** The sqlite3_extended_result_codes() routine enables or disables the
+** [extended result codes] feature of SQLite. The extended result
+** codes are disabled by default for historical compatibility considerations.
 **
-** {F12202} The [sqlite3_extended_result_codes(D,F)] interface will enable
-**          [extended result codes] for the 
-**          [database connection] D if the F parameter
-**          is true, or disable them if F is false.
+** Requirements:
+** [H12201] [H12202]
 */
 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
 
 /*
-** CAPI3REF: Last Insert Rowid {F12220}
+** CAPI3REF: Last Insert Rowid {H12220} <S10700>
 **
 ** Each entry in an SQLite table has a unique 64-bit signed
-** integer key called the "rowid". The rowid is always available
+** integer key called the [ROWID | "rowid"]. The rowid is always available
 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
 ** names are not also used by explicitly declared columns. If
-** the table has a column of type INTEGER PRIMARY KEY then that column
+** the table has a column of type [INTEGER PRIMARY KEY] then that column
 ** is another alias for the rowid.
 **
-** This routine returns the rowid of the most recent
-** successful INSERT into the database from the database connection
-** shown in the first argument.  If no successful inserts
-** have ever occurred on this database connection, zero is returned.
+** This routine returns the [rowid] of the most recent
+** successful [INSERT] into the database from the [database connection]
+** in the first argument.  If no successful [INSERT]s
+** have ever occurred on that database connection, zero is returned.
 **
-** If an INSERT occurs within a trigger, then the rowid of the
-** inserted row is returned by this routine as long as the trigger
-** is running.  But once the trigger terminates, the value returned
-** by this routine reverts to the last value inserted before the
-** trigger fired.
+** If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
+** row is returned by this routine as long as the trigger is running.
+** But once the trigger terminates, the value returned by this routine
+** reverts to the last value inserted before the trigger fired.
 **
-** An INSERT that fails due to a constraint violation is not a
-** successful insert and does not change the value returned by this
+** An [INSERT] that fails due to a constraint violation is not a
+** successful [INSERT] and does not change the value returned by this
 ** routine.  Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
 ** and INSERT OR ABORT make no changes to the return value of this
-** routine when their insertion fails.  When INSERT OR REPLACE 
+** routine when their insertion fails.  When INSERT OR REPLACE
 ** encounters a constraint violation, it does not fail.  The
 ** INSERT continues to completion after deleting rows that caused
 ** the constraint problem so INSERT OR REPLACE will always change
-** the return value of this interface. 
+** the return value of this interface.
 **
-** For the purposes of this routine, an insert is considered to
+** For the purposes of this routine, an [INSERT] is considered to
 ** be successful even if it is subsequently rolled back.
 **
-** INVARIANTS:
-**
-** {F12221} The [sqlite3_last_insert_rowid()] function returns the
-**          rowid of the most recent successful insert done
-**          on the same database connection and within the same
-**          trigger context, or zero if there have
-**          been no qualifying inserts on that connection.
-**
-** {F12223} The [sqlite3_last_insert_rowid()] function returns
-**          same value when called from the same trigger context
-**          immediately before and after a ROLLBACK.
-**
-** LIMITATIONS:
+** Requirements:
+** [H12221] [H12223]
 **
-** {U12232} If a separate thread does a new insert on the same
-**          database connection while the [sqlite3_last_insert_rowid()]
-**          function is running and thus changes the last insert rowid,
-**          then the value returned by [sqlite3_last_insert_rowid()] is
-**          unpredictable and might not equal either the old or the new
-**          last insert rowid.
+** If a separate thread performs a new [INSERT] on the same
+** database connection while the [sqlite3_last_insert_rowid()]
+** function is running and thus changes the last insert [rowid],
+** then the value returned by [sqlite3_last_insert_rowid()] is
+** unpredictable and might not equal either the old or the new
+** last insert [rowid].
 */
 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
 
 /*
-** CAPI3REF: Count The Number Of Rows Modified {F12240}
+** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
 **
 ** This function returns the number of database rows that were changed
 ** or inserted or deleted by the most recently completed SQL statement
-** on the connection specified by the first parameter.  Only
-** changes that are directly specified by the INSERT, UPDATE, or
-** DELETE statement are counted.  Auxiliary changes caused by
-** triggers are not counted. Use the [sqlite3_total_changes()] function
-** to find the total number of changes including changes caused by triggers.
+** on the [database connection] specified by the first parameter.
+** Only changes that are directly specified by the [INSERT], [UPDATE],
+** or [DELETE] statement are counted.  Auxiliary changes caused by
+** triggers or [foreign key actions] are not counted. Use the
+** [sqlite3_total_changes()] function to find the total number of changes
+** including changes caused by triggers and foreign key actions.
+**
+** Changes to a view that are simulated by an [INSTEAD OF trigger]
+** are not counted.  Only real table changes are counted.
 **
 ** A "row change" is a change to a single row of a single table
 ** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
-** are changed as side effects of REPLACE constraint resolution,
-** rollback, ABORT processing, DROP TABLE, or by any other
+** are changed as side effects of [REPLACE] constraint resolution,
+** rollback, ABORT processing, [DROP TABLE], or by any other
 ** mechanisms do not count as direct row changes.
 **
 ** A "trigger context" is a scope of execution that begins and
-** ends with the script of a trigger.  Most SQL statements are
+** ends with the script of a [CREATE TRIGGER | trigger]. 
+** Most SQL statements are
 ** evaluated outside of any trigger.  This is the "top level"
 ** trigger context.  If a trigger fires from the top level, a
 ** new trigger context is entered for the duration of that one
@@ -1348,84 +1876,57 @@ SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
 ** most recent INSERT, UPDATE, or DELETE statement within the same
 ** trigger context.
 **
-** So when called from the top level, this function returns the
+** Thus, when called from the top level, this function returns the
 ** number of changes in the most recent INSERT, UPDATE, or DELETE
-** that also occurred at the top level.
-** Within the body of a trigger, the sqlite3_changes() interface
-** can be called to find the number of
+** that also occurred at the top level.  Within the body of a trigger,
+** the sqlite3_changes() interface can be called to find the number of
 ** changes in the most recently completed INSERT, UPDATE, or DELETE
 ** statement within the body of the same trigger.
-** However, the number returned does not include in changes
-** caused by subtriggers since they have their own context.
-**
-** SQLite implements the command "DELETE FROM table" without
-** a WHERE clause by dropping and recreating the table.  (This is much
-** faster than going through and deleting individual elements from the
-** table.)  Because of this optimization, the deletions in
-** "DELETE FROM table" are not row changes and will not be counted
-** by the sqlite3_changes() or [sqlite3_total_changes()] functions.
-** To get an accurate count of the number of rows deleted, use
-** "DELETE FROM table WHERE 1" instead.
+** However, the number returned does not include changes
+** caused by subtriggers since those have their own context.
 **
-** INVARIANTS:
+** See also the [sqlite3_total_changes()] interface and the
+** [count_changes pragma].
 **
-** {F12241} The [sqlite3_changes()] function returns the number of
-**          row changes caused by the most recent INSERT, UPDATE,
-**          or DELETE statement on the same database connection and
-**          within the same trigger context, or zero if there have
-**          not been any qualifying row changes.
+** Requirements:
+** [H12241] [H12243]
 **
-** LIMITATIONS:
-**
-** {U12252} If a separate thread makes changes on the same database connection
-**          while [sqlite3_changes()] is running then the value returned
-**          is unpredictable and unmeaningful.
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_changes()] is running then the value returned
+** is unpredictable and not meaningful.
 */
 SQLITE_API int sqlite3_changes(sqlite3*);
 
 /*
-** CAPI3REF: Total Number Of Rows Modified {F12260}
-***
-** This function returns the number of row changes caused
-** by INSERT, UPDATE or DELETE statements since the database handle
-** was opened.  The count includes all changes from all trigger
-** contexts.  But the count does not include changes used to
-** implement REPLACE constraints, do rollbacks or ABORT processing,
-** or DROP table processing.
-** The changes
-** are counted as soon as the statement that makes them is completed 
-** (when the statement handle is passed to [sqlite3_reset()] or 
-** [sqlite3_finalize()]).
+** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
 **
-** SQLite implements the command "DELETE FROM table" without
-** a WHERE clause by dropping and recreating the table.  (This is much
-** faster than going
-** through and deleting individual elements from the table.)  Because of
-** this optimization, the change count for "DELETE FROM table" will be
-** zero regardless of the number of elements that were originally in the
-** table. To get an accurate count of the number of rows deleted, use
-** "DELETE FROM table WHERE 1" instead.
-**
-** See also the [sqlite3_changes()] interface.
+** This function returns the number of row changes caused by [INSERT],
+** [UPDATE] or [DELETE] statements since the [database connection] was opened.
+** The count includes all changes from all [CREATE TRIGGER | trigger] 
+** contexts and changes made by [foreign key actions]. However,
+** the count does not include changes used to implement [REPLACE] constraints,
+** do rollbacks or ABORT processing, or [DROP TABLE] processing.  The
+** count does not include rows of views that fire an [INSTEAD OF trigger],
+** though if the INSTEAD OF trigger makes changes of its own, those changes 
+** are counted.
+** The changes are counted as soon as the statement that makes them is
+** completed (when the statement handle is passed to [sqlite3_reset()] or
+** [sqlite3_finalize()]).
 **
-** INVARIANTS:
-** 
-** {F12261} The [sqlite3_total_changes()] returns the total number
-**          of row changes caused by INSERT, UPDATE, and/or DELETE
-**          statements on the same [database connection], in any
-**          trigger context, since the database connection was
-**          created.
+** See also the [sqlite3_changes()] interface and the
+** [count_changes pragma].
 **
-** LIMITATIONS:
+** Requirements:
+** [H12261] [H12263]
 **
-** {U12264} If a separate thread makes changes on the same database connection
-**          while [sqlite3_total_changes()] is running then the value 
-**          returned is unpredictable and unmeaningful.
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_total_changes()] is running then the value
+** returned is unpredictable and not meaningful.
 */
 SQLITE_API int sqlite3_total_changes(sqlite3*);
 
 /*
-** CAPI3REF: Interrupt A Long-Running Query {F12270}
+** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
 **
 ** This function causes any pending database operation to abort and
 ** return at its earliest opportunity. This routine is typically
@@ -1435,98 +1936,99 @@ SQLITE_API int sqlite3_total_changes(sqlite3*);
 **
 ** It is safe to call this routine from a thread different from the
 ** thread that is currently running the database operation.  But it
-** is not safe to call this routine with a database connection that
+** is not safe to call this routine with a [database connection] that
 ** is closed or might close before sqlite3_interrupt() returns.
 **
-** If an SQL is very nearly finished at the time when sqlite3_interrupt()
-** is called, then it might not have an opportunity to be interrupted.
-** It might continue to completion.
-** An SQL operation that is interrupted will return
-** [SQLITE_INTERRUPT].  If the interrupted SQL operation is an
-** INSERT, UPDATE, or DELETE that is inside an explicit transaction, 
-** then the entire transaction will be rolled back automatically.
-** A call to sqlite3_interrupt() has no effect on SQL statements
-** that are started after sqlite3_interrupt() returns.
-**
-** INVARIANTS:
+** If an SQL operation is very nearly finished at the time when
+** sqlite3_interrupt() is called, then it might not have an opportunity
+** to be interrupted and might continue to completion.
 **
-** {F12271} The [sqlite3_interrupt()] interface will force all running
-**          SQL statements associated with the same database connection
-**          to halt after processing at most one additional row of
-**          data.
+** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
+** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
+** that is inside an explicit transaction, then the entire transaction
+** will be rolled back automatically.
 **
-** {F12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
-**          will return [SQLITE_INTERRUPT].
+** The sqlite3_interrupt(D) call is in effect until all currently running
+** SQL statements on [database connection] D complete.  Any new SQL statements
+** that are started after the sqlite3_interrupt() call and before the 
+** running statements reaches zero are interrupted as if they had been
+** running prior to the sqlite3_interrupt() call.  New SQL statements
+** that are started after the running statement count reaches zero are
+** not effected by the sqlite3_interrupt().
+** A call to sqlite3_interrupt(D) that occurs when there are no running
+** SQL statements is a no-op and has no effect on SQL statements
+** that are started after the sqlite3_interrupt() call returns.
 **
-** LIMITATIONS:
+** Requirements:
+** [H12271] [H12272]
 **
-** {U12279} If the database connection closes while [sqlite3_interrupt()]
-**          is running then bad things will likely happen.
+** If the database connection closes while [sqlite3_interrupt()]
+** is running then bad things will likely happen.
 */
 SQLITE_API void sqlite3_interrupt(sqlite3*);
 
 /*
-** CAPI3REF: Determine If An SQL Statement Is Complete {F10510}
+** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
 **
-** These routines are useful for command-line input to determine if the
-** currently entered text seems to form complete a SQL statement or
+** These routines are useful during command-line input to determine if the
+** currently entered text seems to form a complete SQL statement or
 ** if additional input is needed before sending the text into
-** SQLite for parsing.  These routines return true if the input string
+** SQLite for parsing.  These routines return 1 if the input string
 ** appears to be a complete SQL statement.  A statement is judged to be
-** complete if it ends with a semicolon token and is not a fragment of a
-** CREATE TRIGGER statement.  Semicolons that are embedded within
+** complete if it ends with a semicolon token and is not a prefix of a
+** well-formed CREATE TRIGGER statement.  Semicolons that are embedded within
 ** string literals or quoted identifier names or comments are not
 ** independent tokens (they are part of the token in which they are
-** embedded) and thus do not count as a statement terminator.
+** embedded) and thus do not count as a statement terminator.  Whitespace
+** and comments that follow the final semicolon are ignored.
 **
-** These routines do not parse the SQL and
-** so will not detect syntactically incorrect SQL.
+** These routines return 0 if the statement is incomplete.  If a
+** memory allocation fails, then SQLITE_NOMEM is returned.
 **
-** INVARIANTS:
+** These routines do not parse the SQL statements thus
+** will not detect syntactically incorrect SQL.
 **
-** {F10511} The sqlite3_complete() and sqlite3_complete16() functions
-**          return true (non-zero) if and only if the last
-**          non-whitespace token in their input is a semicolon that
-**          is not in between the BEGIN and END of a CREATE TRIGGER
-**          statement.
+** If SQLite has not been initialized using [sqlite3_initialize()] prior 
+** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
+** automatically by sqlite3_complete16().  If that initialization fails,
+** then the return value from sqlite3_complete16() will be non-zero
+** regardless of whether or not the input SQL is complete.
 **
-** LIMITATIONS:
+** Requirements: [H10511] [H10512]
 **
-** {U10512} The input to sqlite3_complete() must be a zero-terminated
-**          UTF-8 string.
+** The input to [sqlite3_complete()] must be a zero-terminated
+** UTF-8 string.
 **
-** {U10513} The input to sqlite3_complete16() must be a zero-terminated
-**          UTF-16 string in native byte order.
+** The input to [sqlite3_complete16()] must be a zero-terminated
+** UTF-16 string in native byte order.
 */
 SQLITE_API int sqlite3_complete(const char *sql);
 SQLITE_API int sqlite3_complete16(const void *sql);
 
 /*
-** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {F12310}
-**
-** This routine identifies a callback function that might be
-** invoked whenever an attempt is made to open a database table 
-** that another thread or process has locked.
-** If the busy callback is NULL, then [SQLITE_BUSY]
-** or [SQLITE_IOERR_BLOCKED]
-** is returned immediately upon encountering the lock.
-** If the busy callback is not NULL, then the
-** callback will be invoked with two arguments.  The
-** first argument to the handler is a copy of the void* pointer which
-** is the third argument to this routine.  The second argument to
-** the handler is the number of times that the busy handler has
-** been invoked for this locking event.   If the
+** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
+**
+** This routine sets a callback function that might be invoked whenever
+** an attempt is made to open a database table that another thread
+** or process has locked.
+**
+** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
+** is returned immediately upon encountering the lock. If the busy callback
+** is not NULL, then the callback will be invoked with two arguments.
+**
+** The first argument to the handler is a copy of the void* pointer which
+** is the third argument to sqlite3_busy_handler().  The second argument to
+** the handler callback is the number of times that the busy handler has
+** been invoked for this locking event.  If the
 ** busy callback returns 0, then no additional attempts are made to
 ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
 ** If the callback returns non-zero, then another attempt
 ** is made to open the database for reading and the cycle repeats.
 **
-** The presence of a busy handler does not guarantee that
-** it will be invoked when there is lock contention.
-** If SQLite determines that invoking the busy handler could result in
-** a deadlock, it will go ahead and return [SQLITE_BUSY] or
-** [SQLITE_IOERR_BLOCKED] instead of invoking the
-** busy handler.
+** The presence of a busy handler does not guarantee that it will be invoked
+** when there is lock contention. If SQLite determines that invoking the busy
+** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
+** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
 ** Consider a scenario where one process is holding a read lock that
 ** it is trying to promote to a reserved lock and
 ** a second process is holding a reserved lock that it is trying
@@ -1551,82 +2053,52 @@ SQLITE_API int sqlite3_complete16(const void *sql);
 ** code is promoted from the relatively benign [SQLITE_BUSY] to
 ** the more severe [SQLITE_IOERR_BLOCKED].  This error code promotion
 ** forces an automatic rollback of the changes.  See the
-** <a href="http://www.sqlite.org/cvstrac/wiki?p=CorruptionFollowingBusyError">
+** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
 ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
 ** this is important.
-**	
-** There can only be a single busy handler defined for each database
-** connection.  Setting a new busy handler clears any previous one. 
-** Note that calling [sqlite3_busy_timeout()] will also set or clear
-** the busy handler.
-**
-** INVARIANTS:
 **
-** {F12311} The [sqlite3_busy_handler()] function replaces the busy handler
-**          callback in the database connection identified by the 1st
-**          parameter with a new busy handler identified by the 2nd and 3rd
-**          parameters.
+** There can only be a single busy handler defined for each
+** [database connection].  Setting a new busy handler clears any
+** previously set handler.  Note that calling [sqlite3_busy_timeout()]
+** will also set or clear the busy handler.
 **
-** {F12312} The default busy handler for new database connections is NULL.
-**
-** {F12314} When two or more database connection share a common cache,
-**          the busy handler for the database connection currently using
-**          the cache is invoked when the cache encounters a lock.
-**
-** {F12316} If a busy handler callback returns zero, then the SQLite
-**          interface that provoked the locking event will return
-**          [SQLITE_BUSY].
-**
-** {F12318} SQLite will invokes the busy handler with two argument which
-**          are a copy of the pointer supplied by the 3rd parameter to
-**          [sqlite3_busy_handler()] and a count of the number of prior
-**          invocations of the busy handler for the same locking event.
-**
-** LIMITATIONS:
+** The busy callback should not take any actions which modify the
+** database connection that invoked the busy handler.  Any such actions
+** result in undefined behavior.
+** 
+** Requirements:
+** [H12311] [H12312] [H12314] [H12316] [H12318]
 **
-** {U12319} A busy handler should not call close the database connection
-**          or prepared statement that invoked the busy handler.
+** A busy handler must not close the database connection
+** or [prepared statement] that invoked the busy handler.
 */
 SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
 
 /*
-** CAPI3REF: Set A Busy Timeout {F12340}
+** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
 **
-** This routine sets a [sqlite3_busy_handler | busy handler]
-** that sleeps for a while when a
-** table is locked.  The handler will sleep multiple times until 
-** at least "ms" milliseconds of sleeping have been done. {F12343} After
-** "ms" milliseconds of sleeping, the handler returns 0 which
-** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
+** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
+** for a specified amount of time when a table is locked.  The handler
+** will sleep multiple times until at least "ms" milliseconds of sleeping
+** have accumulated. {H12343} After "ms" milliseconds of sleeping,
+** the handler returns 0 which causes [sqlite3_step()] to return
+** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
 **
 ** Calling this routine with an argument less than or equal to zero
 ** turns off all busy handlers.
 **
-** There can only be a single busy handler for a particular database
-** connection.  If another busy handler was defined  
-** (using [sqlite3_busy_handler()]) prior to calling
+** There can only be a single busy handler for a particular
+** [database connection] any any given moment.  If another busy handler
+** was defined  (using [sqlite3_busy_handler()]) prior to calling
 ** this routine, that other busy handler is cleared.
 **
-** INVARIANTS:
-**
-** {F12341} The [sqlite3_busy_timeout()] function overrides any prior
-**          [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
-**          on the same database connection.
-**
-** {F12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
-**          or equal to zero, then the busy handler is cleared so that
-**          all subsequent locking events immediately return [SQLITE_BUSY].
-**
-** {F12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
-**          number N, then a busy handler is set that repeatedly calls
-**          the xSleep() method in the VFS interface until either the
-**          lock clears or until the cumulative sleep time reported back
-**          by xSleep() exceeds N milliseconds.
+** Requirements:
+** [H12341] [H12343] [H12344]
 */
 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
 
 /*
-** CAPI3REF: Convenience Routines For Running Queries {F12370}
+** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
 **
 ** Definition: A <b>result table</b> is memory data structure created by the
 ** [sqlite3_get_table()] interface.  A result table records the
@@ -1637,16 +2109,14 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
 ** numbers are obtained separately.  Let N be the number of rows
 ** and M be the number of columns.
 **
-** A result table is an array of pointers to zero-terminated
-** UTF-8 strings.  There are (N+1)*M elements in the array.  
-** The first M pointers point to zero-terminated strings that 
-** contain the names of the columns.
-** The remaining entries all point to query results.  NULL
-** values are give a NULL pointer.  All other values are in
-** their UTF-8 zero-terminated string representation as returned by
-** [sqlite3_column_text()].
+** A result table is an array of pointers to zero-terminated UTF-8 strings.
+** There are (N+1)*M elements in the array.  The first M pointers point
+** to zero-terminated strings that  contain the names of the columns.
+** The remaining entries all point to query results.  NULL values result
+** in NULL pointers.  All other values are in their UTF-8 zero-terminated
+** string representation as returned by [sqlite3_column_text()].
 **
-** A result table might consists of one or more memory allocations.
+** A result table might consist of one or more memory allocations.
 ** It is not safe to pass a result table directly to [sqlite3_free()].
 ** A result table should be deallocated using [sqlite3_free_table()].
 **
@@ -1681,11 +2151,11 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
 ** string of its 2nd parameter.  It returns a result table to the
 ** pointer given in its 3rd parameter.
 **
-** After the calling function has finished using the result, it should 
-** pass the pointer to the result table to sqlite3_free_table() in order to 
-** release the memory that was malloc-ed.  Because of the way the 
+** After the calling function has finished using the result, it should
+** pass the pointer to the result table to sqlite3_free_table() in order to
+** release the memory that was malloced.  Because of the way the
 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
-** function must not try to call [sqlite3_free()] directly.  Only 
+** function must not try to call [sqlite3_free()] directly.  Only
 ** [sqlite3_free_table()] is able to release the memory properly and safely.
 **
 ** The sqlite3_get_table() interface is implemented as a wrapper around
@@ -1693,51 +2163,31 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
 ** to any internal data structures of SQLite.  It uses only the public
 ** interface defined here.  As a consequence, errors that occur in the
 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
-** reflected in subsequent calls to [sqlite3_errcode()] or
-** [sqlite3_errmsg()].
+** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
 **
-** INVARIANTS:
-**
-** {F12371} If a [sqlite3_get_table()] fails a memory allocation, then
-**          it frees the result table under construction, aborts the
-**          query in process, skips any subsequent queries, sets the
-**          *resultp output pointer to NULL and returns [SQLITE_NOMEM].
-**
-** {F12373} If the ncolumn parameter to [sqlite3_get_table()] is not NULL
-**          then [sqlite3_get_table()] write the number of columns in the
-**          result set of the query into *ncolumn if the query is
-**          successful (if the function returns SQLITE_OK).
-**
-** {F12374} If the nrow parameter to [sqlite3_get_table()] is not NULL
-**          then [sqlite3_get_table()] write the number of rows in the
-**          result set of the query into *nrow if the query is
-**          successful (if the function returns SQLITE_OK).
-**
-** {F12376} The [sqlite3_get_table()] function sets its *ncolumn value
-**          to the number of columns in the result set of the query in the
-**          sql parameter, or to zero if the query in sql has an empty
-**          result set.
+** Requirements:
+** [H12371] [H12373] [H12374] [H12376] [H12379] [H12382]
 */
 SQLITE_API int sqlite3_get_table(
-  sqlite3*,             /* An open database */
-  const char *sql,      /* SQL to be evaluated */
-  char ***pResult,      /* Results of the query */
-  int *nrow,            /* Number of result rows written here */
-  int *ncolumn,         /* Number of result columns written here */
-  char **errmsg         /* Error msg written here */
+  sqlite3 *db,          /* An open database */
+  const char *zSql,     /* SQL to be evaluated */
+  char ***pazResult,    /* Results of the query */
+  int *pnRow,           /* Number of result rows written here */
+  int *pnColumn,        /* Number of result columns written here */
+  char **pzErrmsg       /* Error msg written here */
 );
 SQLITE_API void sqlite3_free_table(char **result);
 
 /*
-** CAPI3REF: Formatted String Printing Functions {F17400}
+** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
 **
-** These routines are workalikes of the "printf()" family of functions
+** These routines are work-alikes of the "printf()" family of functions
 ** from the standard C library.
 **
 ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
 ** results into memory obtained from [sqlite3_malloc()].
 ** The strings returned by these two routines should be
-** released by [sqlite3_free()].   Both routines return a
+** released by [sqlite3_free()].  Both routines return a
 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
 ** memory to hold the resulting string.
 **
@@ -1762,7 +2212,7 @@ SQLITE_API void sqlite3_free_table(char **result);
 **
 ** These routines all implement some additional formatting
 ** options that are useful for constructing SQL statements.
-** All of the usual printf formatting options apply.  In addition, there
+** All of the usual printf() formatting options apply.  In addition, there
 ** is are "%q", "%Q", and "%z" options.
 **
 ** The %q option works like %s in that it substitutes a null-terminated
@@ -1771,7 +2221,7 @@ SQLITE_API void sqlite3_free_table(char **result);
 ** character it escapes that character and allows it to be inserted into
 ** the string.
 **
-** For example, so some string variable contains text as follows:
+** For example, assume the string variable zText contains text as follows:
 **
 ** <blockquote><pre>
 **  char *zText = "It's a happy day!";
@@ -1799,14 +2249,13 @@ SQLITE_API void sqlite3_free_table(char **result);
 **  INSERT INTO table1 VALUES('It's a happy day!');
 ** </pre></blockquote>
 **
-** This second example is an SQL syntax error.  As a general rule you
-** should always use %q instead of %s when inserting text into a string 
-** literal.
+** This second example is an SQL syntax error.  As a general rule you should
+** always use %q instead of %s when inserting text into a string literal.
 **
 ** The %Q option works like %q except it also adds single quotes around
-** the outside of the total string.  Or if the parameter in the argument
-** list is a NULL pointer, %Q substitutes the text "NULL" (without single
-** quotes) in place of the %Q option. {END}  So, for example, one could say:
+** the outside of the total string.  Additionally, if the parameter in the
+** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
+** single quotes) in place of the %Q option.  So, for example, one could say:
 **
 ** <blockquote><pre>
 **  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
@@ -1821,35 +2270,20 @@ SQLITE_API void sqlite3_free_table(char **result);
 ** addition that after the string has been read and copied into
 ** the result, [sqlite3_free()] is called on the input string. {END}
 **
-** INVARIANTS:
-**
-** {F17403}  The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
-**           return either pointers to zero-terminated UTF-8 strings held in
-**           memory obtained from [sqlite3_malloc()] or NULL pointers if
-**           a call to [sqlite3_malloc()] fails.
-**
-** {F17406}  The [sqlite3_snprintf()] interface writes a zero-terminated
-**           UTF-8 string into the buffer pointed to by the second parameter
-**           provided that the first parameter is greater than zero.
-**
-** {F17407}  The [sqlite3_snprintf()] interface does not writes slots of
-**           its output buffer (the second parameter) outside the range
-**           of 0 through N-1 (where N is the first parameter)
-**           regardless of the length of the string
-**           requested by the format specification.
-**   
+** Requirements:
+** [H17403] [H17406] [H17407]
 */
 SQLITE_API char *sqlite3_mprintf(const char*,...);
 SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 
 /*
-** CAPI3REF: Memory Allocation Subsystem {F17300}
+** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
 **
 ** The SQLite core  uses these three routines for all of its own
 ** internal memory allocation needs. "Core" in the previous sentence
 ** does not include operating-system specific VFS implementation.  The
-** windows VFS uses native malloc and free for some operations.
+** Windows VFS uses native malloc() and free() for some operations.
 **
 ** The sqlite3_malloc() routine returns a pointer to a block
 ** of memory at least N bytes in length, where N is the parameter.
@@ -1867,7 +2301,7 @@ SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 ** memory might result in a segmentation fault or other severe error.
 ** Memory corruption, a segmentation fault, or other severe error
 ** might result if sqlite3_free() is called with a non-NULL pointer that
-** was not obtained from sqlite3_malloc() or sqlite3_free().
+** was not obtained from sqlite3_malloc() or sqlite3_realloc().
 **
 ** The sqlite3_realloc() interface attempts to resize a
 ** prior memory allocation to be at least N bytes, where N is the
@@ -1878,7 +2312,7 @@ SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 ** If the second parameter to sqlite3_realloc() is zero or
 ** negative then the behavior is exactly the same as calling
 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
-** Sqlite3_realloc() returns a pointer to a memory allocation
+** sqlite3_realloc() returns a pointer to a memory allocation
 ** of at least N bytes in size or NULL if sufficient memory is unavailable.
 ** If M is the size of the prior allocation, then min(N,M) bytes
 ** of the prior allocation are copied into the beginning of buffer returned
@@ -1889,128 +2323,66 @@ SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 ** The memory returned by sqlite3_malloc() and sqlite3_realloc()
 ** is always aligned to at least an 8 byte boundary. {END}
 **
-** The default implementation
-** of the memory allocation subsystem uses the malloc(), realloc()
-** and free() provided by the standard C library. {F17382} However, if 
-** SQLite is compiled with the following C preprocessor macro
-**
-** <blockquote> SQLITE_MEMORY_SIZE=<i>NNN</i> </blockquote>
-**
-** where <i>NNN</i> is an integer, then SQLite create a static
-** array of at least <i>NNN</i> bytes in size and use that array
-** for all of its dynamic memory allocation needs. {END}  Additional
-** memory allocator options may be added in future releases.
+** The default implementation of the memory allocation subsystem uses
+** the malloc(), realloc() and free() provided by the standard C library.
+** {H17382} However, if SQLite is compiled with the
+** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
+** is an integer), then SQLite create a static array of at least
+** <i>NNN</i> bytes in size and uses that array for all of its dynamic
+** memory allocation needs. {END}  Additional memory allocator options
+** may be added in future releases.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
 ** implementation of these routines to be omitted.  That capability
-** is no longer provided.  Only built-in memory allocators can be
-** used.
+** is no longer provided.  Only built-in memory allocators can be used.
 **
-** The windows OS interface layer calls
+** The Windows OS interface layer calls
 ** the system malloc() and free() directly when converting
 ** filenames between the UTF-8 encoding used by SQLite
-** and whatever filename encoding is used by the particular windows
+** and whatever filename encoding is used by the particular Windows
 ** installation.  Memory allocation errors are detected, but
 ** they are reported back as [SQLITE_CANTOPEN] or
 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
 **
-** INVARIANTS:
-**
-** {F17303}  The [sqlite3_malloc(N)] interface returns either a pointer to 
-**           newly checked-out block of at least N bytes of memory
-**           that is 8-byte aligned, 
-**           or it returns NULL if it is unable to fulfill the request.
-**
-** {F17304}  The [sqlite3_malloc(N)] interface returns a NULL pointer if
-**           N is less than or equal to zero.
-**
-** {F17305}  The [sqlite3_free(P)] interface releases memory previously
-**           returned from [sqlite3_malloc()] or [sqlite3_realloc()],
-**           making it available for reuse.
-**
-** {F17306}  A call to [sqlite3_free(NULL)] is a harmless no-op.
-**
-** {F17310}  A call to [sqlite3_realloc(0,N)] is equivalent to a call
-**           to [sqlite3_malloc(N)].
-**
-** {F17312}  A call to [sqlite3_realloc(P,0)] is equivalent to a call
-**           to [sqlite3_free(P)].
+** Requirements:
+** [H17303] [H17304] [H17305] [H17306] [H17310] [H17312] [H17315] [H17318]
+** [H17321] [H17322] [H17323]
 **
-** {F17315}  The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
-**           and [sqlite3_free()] for all of its memory allocation and
-**           deallocation needs.
-**
-** {F17318}  The [sqlite3_realloc(P,N)] interface returns either a pointer
-**           to a block of checked-out memory of at least N bytes in size
-**           that is 8-byte aligned, or a NULL pointer.
-**
-** {F17321}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
-**           copies the first K bytes of content from P into the newly allocated
-**           where K is the lessor of N and the size of the buffer P.
-**
-** {F17322}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
-**           releases the buffer P.
-**
-** {F17323}  When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
-**           not modified or released.
-**
-** LIMITATIONS:
-**
-** {U17350}  The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
-**           must be either NULL or else a pointer obtained from a prior
-**           invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that has
-**           not been released.
-**
-** {U17351}  The application must not read or write any part of 
-**           a block of memory after it has been released using
-**           [sqlite3_free()] or [sqlite3_realloc()].
+** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+** must be either NULL or else pointers obtained from a prior
+** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+** not yet been released.
 **
+** The application must not read or write any part of
+** a block of memory after it has been released using
+** [sqlite3_free()] or [sqlite3_realloc()].
 */
 SQLITE_API void *sqlite3_malloc(int);
 SQLITE_API void *sqlite3_realloc(void*, int);
 SQLITE_API void sqlite3_free(void*);
 
 /*
-** CAPI3REF: Memory Allocator Statistics {F17370}
+** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
 **
 ** SQLite provides these two interfaces for reporting on the status
 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
-** the memory allocation subsystem included within the SQLite.
-**
-** INVARIANTS:
-**
-** {F17371} The [sqlite3_memory_used()] routine returns the
-**          number of bytes of memory currently outstanding 
-**          (malloced but not freed).
+** routines, which form the built-in memory allocation subsystem.
 **
-** {F17373} The [sqlite3_memory_highwater()] routine returns the maximum
-**          value of [sqlite3_memory_used()] 
-**          since the highwater mark was last reset.
-**
-** {F17374} The values returned by [sqlite3_memory_used()] and
-**          [sqlite3_memory_highwater()] include any overhead
-**          added by SQLite in its implementation of [sqlite3_malloc()],
-**          but not overhead added by the any underlying system library
-**          routines that [sqlite3_malloc()] may call.
-** 
-** {F17375} The memory highwater mark is reset to the current value of
-**          [sqlite3_memory_used()] if and only if the parameter to
-**          [sqlite3_memory_highwater()] is true.  The value returned
-**          by [sqlite3_memory_highwater(1)] is the highwater mark
-**          prior to the reset.
+** Requirements:
+** [H17371] [H17373] [H17374] [H17375]
 */
 SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 
 /*
-** CAPI3REF: Pseudo-Random Number Generator {F17390}
+** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
 **
 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
-** select random ROWIDs when inserting new records into a table that
-** already uses the largest possible ROWID.  The PRNG is also used for
+** select random [ROWID | ROWIDs] when inserting new records into a table that
+** already uses the largest possible [ROWID].  The PRNG is also used for
 ** the build-in random() and randomblob() SQL functions.  This interface allows
-** appliations to access the same PRNG for other purposes.
+** applications to access the same PRNG for other purposes.
 **
 ** A call to this routine stores N bytes of randomness into buffer P.
 **
@@ -2021,15 +2393,13 @@ SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 ** internally and without recourse to the [sqlite3_vfs] xRandomness
 ** method.
 **
-** INVARIANTS:
-**
-** {F17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
-**          high-quality pseudo-randomness into buffer P.
+** Requirements:
+** [H17392]
 */
 SQLITE_API void sqlite3_randomness(int N, void *P);
 
 /*
-** CAPI3REF: Compile-Time Authorization Callbacks {F12500}
+** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
 **
 ** This routine registers a authorizer callback with a particular
 ** [database connection], supplied in the first argument.
@@ -2042,36 +2412,39 @@ SQLITE_API void sqlite3_randomness(int N, void *P);
 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
 ** specific action but allow the SQL statement to continue to be
 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
-** rejected with an error.   If the authorizer callback returns
+** rejected with an error.  If the authorizer callback returns
 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
-** then [sqlite3_prepare_v2()] or equivalent call that triggered
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
 ** the authorizer will fail with an error message.
 **
 ** When the callback returns [SQLITE_OK], that means the operation
 ** requested is ok.  When the callback returns [SQLITE_DENY], the
 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
 ** authorizer will fail with an error message explaining that
-** access is denied.  If the authorizer code is [SQLITE_READ]
+** access is denied. 
+**
+** The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. The third through sixth parameters
+** to the callback are zero-terminated strings that contain additional
+** details about the action to be authorized.
+**
+** If the action code is [SQLITE_READ]
 ** and the callback returns [SQLITE_IGNORE] then the
 ** [prepared statement] statement is constructed to substitute
 ** a NULL value in place of the table column that would have
 ** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
 ** return can be used to deny an untrusted user access to individual
 ** columns of a table.
-**
-** The first parameter to the authorizer callback is a copy of
-** the third parameter to the sqlite3_set_authorizer() interface.
-** The second parameter to the callback is an integer 
-** [SQLITE_COPY | action code] that specifies the particular action
-** to be authorized. The third through sixth
-** parameters to the callback are zero-terminated strings that contain 
-** additional details about the action to be authorized.
+** If the action code is [SQLITE_DELETE] and the callback returns
+** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
+** [truncate optimization] is disabled and all rows are deleted individually.
 **
 ** An authorizer is used when [sqlite3_prepare | preparing]
-** SQL statements from an untrusted
-** source, to ensure that the SQL statements do not try to access data
-** that they are not allowed to see, or that they do not try to
-** execute malicious statements that damage the database.  For
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database.  For
 ** example, an application may allow a user to enter arbitrary
 ** SQL queries for evaluation by a database.  But the application does
 ** not want the user to be able to make arbitrary changes to the
@@ -2089,61 +2462,25 @@ SQLITE_API void sqlite3_randomness(int N, void *P);
 ** previous call.  Disable the authorizer by installing a NULL callback.
 ** The authorizer is disabled by default.
 **
-** Note that the authorizer callback is invoked only during 
-** [sqlite3_prepare()] or its variants.  Authorization is not
-** performed during statement evaluation in [sqlite3_step()].
-**
-** INVARIANTS:
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12501} The [sqlite3_set_authorizer(D,...)] interface registers a
-**          authorizer callback with database connection D.
+** When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be re-prepared during [sqlite3_step()] due to a 
+** schema change.  Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
 **
-** {F12502} The authorizer callback is invoked as SQL statements are
-**          being compiled
-**
-** {F12503} If the authorizer callback returns any value other than
-**          [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] then
-**          the [sqlite3_prepare_v2()] or equivalent call that caused
-**          the authorizer callback to run shall fail with an
-**          [SQLITE_ERROR] error code and an appropriate error message.
-**
-** {F12504} When the authorizer callback returns [SQLITE_OK], the operation
-**          described is coded normally.
-**
-** {F12505} When the authorizer callback returns [SQLITE_DENY], the
-**          [sqlite3_prepare_v2()] or equivalent call that caused the
-**          authorizer callback to run shall fail
-**          with an [SQLITE_ERROR] error code and an error message
-**          explaining that access is denied.
-**
-** {F12506} If the authorizer code (the 2nd parameter to the authorizer
-**          callback) is [SQLITE_READ] and the authorizer callback returns
-**          [SQLITE_IGNORE] then the prepared statement is constructed to
-**          insert a NULL value in place of the table column that would have
-**          been read if [SQLITE_OK] had been returned.
-**
-** {F12507} If the authorizer code (the 2nd parameter to the authorizer
-**          callback) is anything other than [SQLITE_READ], then
-**          a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY]. 
-**
-** {F12510} The first parameter to the authorizer callback is a copy of
-**          the third parameter to the [sqlite3_set_authorizer()] interface.
-**
-** {F12511} The second parameter to the callback is an integer 
-**          [SQLITE_COPY | action code] that specifies the particular action
-**          to be authorized.
-**
-** {F12512} The third through sixth parameters to the callback are
-**          zero-terminated strings that contain 
-**          additional details about the action to be authorized.
-**
-** {F12520} Each call to [sqlite3_set_authorizer()] overrides the
-**          any previously installed authorizer.
-**
-** {F12521} A NULL authorizer means that no authorization
-**          callback is invoked.
+** Note that the authorizer callback is invoked only during
+** [sqlite3_prepare()] or its variants.  Authorization is not
+** performed during statement evaluation in [sqlite3_step()], unless
+** as stated in the previous paragraph, sqlite3_step() invokes
+** sqlite3_prepare_v2() to reprepare a statement after a schema change.
 **
-** {F12522} The default authorizer is NULL.
+** Requirements:
+** [H12501] [H12502] [H12503] [H12504] [H12505] [H12506] [H12507] [H12510]
+** [H12511] [H12512] [H12520] [H12521] [H12522]
 */
 SQLITE_API int sqlite3_set_authorizer(
   sqlite3*,
@@ -2152,7 +2489,7 @@ SQLITE_API int sqlite3_set_authorizer(
 );
 
 /*
-** CAPI3REF: Authorizer Return Codes {F12590}
+** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
 **
 ** The [sqlite3_set_authorizer | authorizer callback function] must
 ** return either [SQLITE_OK] or one of these two constants in order
@@ -2164,45 +2501,26 @@ SQLITE_API int sqlite3_set_authorizer(
 #define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
 
 /*
-** CAPI3REF: Authorizer Action Codes {F12550}
+** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
 **
 ** The [sqlite3_set_authorizer()] interface registers a callback function
-** that is invoked to authorizer certain SQL statement actions.  The
+** that is invoked to authorize certain SQL statement actions.  The
 ** second parameter to the callback is an integer code that specifies
 ** what action is being authorized.  These are the integer action codes that
 ** the authorizer callback may be passed.
 **
-** These action code values signify what kind of operation is to be 
+** These action code values signify what kind of operation is to be
 ** authorized.  The 3rd and 4th parameters to the authorization
 ** callback function will be parameters or NULL depending on which of these
 ** codes is used as the second parameter.  The 5th parameter to the
-** authorizer callback is the name of the database ("main", "temp", 
+** authorizer callback is the name of the database ("main", "temp",
 ** etc.) if applicable.  The 6th parameter to the authorizer callback
 ** is the name of the inner-most trigger or view that is responsible for
-** the access attempt or NULL if this access attempt is directly from 
+** the access attempt or NULL if this access attempt is directly from
 ** top-level SQL code.
 **
-** INVARIANTS:
-**
-** {F12551} The second parameter to an 
-**          [sqlite3_set_authorizer | authorizer callback is always an integer
-**          [SQLITE_COPY | authorizer code] that specifies what action
-**          is being authorized.
-**
-** {F12552} The 3rd and 4th parameters to the 
-**          [sqlite3_set_authorizer | authorization callback function]
-**          will be parameters or NULL depending on which 
-**          [SQLITE_COPY | authorizer code] is used as the second parameter.
-**
-** {F12553} The 5th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
-**          of the database (example: "main", "temp", etc.) if applicable.
-**
-** {F12554} The 6th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
-**          of the inner-most trigger or view that is responsible for
-**          the access attempt or NULL if this access attempt is directly from 
-**          top-level SQL code.
+** Requirements:
+** [H12551] [H12552] [H12553] [H12554]
 */
 /******************************************* 3rd ************ 4th ***********/
 #define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
@@ -2226,7 +2544,7 @@ SQLITE_API int sqlite3_set_authorizer(
 #define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
 #define SQLITE_READ                 20   /* Table Name      Column Name     */
 #define SQLITE_SELECT               21   /* NULL            NULL            */
-#define SQLITE_TRANSACTION          22   /* NULL            NULL            */
+#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
 #define SQLITE_UPDATE               23   /* Table Name      Column Name     */
 #define SQLITE_ATTACH               24   /* Filename        NULL            */
 #define SQLITE_DETACH               25   /* Database Name   NULL            */
@@ -2235,11 +2553,13 @@ SQLITE_API int sqlite3_set_authorizer(
 #define SQLITE_ANALYZE              28   /* Table Name      NULL            */
 #define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
 #define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
-#define SQLITE_FUNCTION             31   /* Function Name   NULL            */
+#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
+#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
 #define SQLITE_COPY                  0   /* No longer used */
 
 /*
-** CAPI3REF: Tracing And Profiling Functions {F12280}
+** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
+** EXPERIMENTAL
 **
 ** These routines register callback functions that can be used for
 ** tracing and profiling the execution of SQL statements.
@@ -2248,245 +2568,136 @@ SQLITE_API int sqlite3_set_authorizer(
 ** various times when an SQL statement is being run by [sqlite3_step()].
 ** The callback returns a UTF-8 rendering of the SQL statement text
 ** as the statement first begins executing.  Additional callbacks occur
-** as each triggersubprogram is entered.  The callbacks for triggers
+** as each triggered subprogram is entered.  The callbacks for triggers
 ** contain a UTF-8 SQL comment that identifies the trigger.
-** 
+**
 ** The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  The profile callback contains
 ** the original statement text and an estimate of wall-clock time
 ** of how long that statement took to run.
 **
-** The sqlite3_profile() API is currently considered experimental and
-** is subject to change or removal in a future release.
-**
-** The trigger reporting feature of the trace callback is considered
-** experimental and is subject to change or removal in future releases.
-** Future versions of SQLite might also add new trace callback 
-** invocations.
-**
-** INVARIANTS:
-**
-** {F12281} The callback function registered by [sqlite3_trace()] is
-**          whenever an SQL statement first begins to execute and
-**          whenever a trigger subprogram first begins to run.
-**
-** {F12282} Each call to [sqlite3_trace()] overrides the previously
-**          registered trace callback.
-**
-** {F12283} A NULL trace callback disables tracing.
-**
-** {F12284} The first argument to the trace callback is a copy of
-**          the pointer which was the 3rd argument to [sqlite3_trace()].
-**
-** {F12285} The second argument to the trace callback is a
-**          zero-terminated UTF8 string containing the original text
-**          of the SQL statement as it was passed into [sqlite3_prepare_v2()]
-**          or the equivalent, or an SQL comment indicating the beginning
-**          of a trigger subprogram.
-**
-** {F12287} The callback function registered by [sqlite3_profile()] is invoked
-**          as each SQL statement finishes.
-**
-** {F12288} The first parameter to the profile callback is a copy of
-**          the 3rd parameter to [sqlite3_profile()].
-**
-** {F12289} The second parameter to the profile callback is a
-**          zero-terminated UTF-8 string that contains the complete text of
-**          the SQL statement as it was processed by [sqlite3_prepare_v2()]
-**          or the equivalent.
-**
-** {F12290} The third parameter to the profile  callback is an estimate
-**          of the number of nanoseconds of wall-clock time required to
-**          run the SQL statement from start to finish.
+** Requirements:
+** [H12281] [H12282] [H12283] [H12284] [H12285] [H12287] [H12288] [H12289]
+** [H12290]
 */
-SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
-SQLITE_API void *sqlite3_profile(sqlite3*,
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
    void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
 
 /*
-** CAPI3REF: Query Progress Callbacks {F12910}
+** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
 **
 ** This routine configures a callback function - the
 ** progress callback - that is invoked periodically during long
 ** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].   An example use for this 
+** [sqlite3_get_table()].  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
-** If the progress callback returns non-zero, the opertion is
+** If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
-** "Cancel" button on a GUI dialog box.
+** "Cancel" button on a GUI progress dialog box.
 **
-** INVARIANTS:
+** The progress handler must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12911} The callback function registered by [sqlite3_progress_handler()]
-**          is invoked periodically during long running calls to
-**          [sqlite3_step()].
+** Requirements:
+** [H12911] [H12912] [H12913] [H12914] [H12915] [H12916] [H12917] [H12918]
 **
-** {F12912} The progress callback is invoked once for every N virtual
-**          machine opcodes, where N is the second argument to 
-**          the [sqlite3_progress_handler()] call that registered
-**          the callback.  <todo>What if N is less than 1?</todo>
-**
-** {F12913} The progress callback itself is identified by the third
-**          argument to [sqlite3_progress_handler()].
-**
-** {F12914} The fourth argument [sqlite3_progress_handler()] is a
-***         void pointer passed to the progress callback
-**          function each time it is invoked.
-**
-** {F12915} If a call to [sqlite3_step()] results in fewer than
-**          N opcodes being executed,
-**          then the progress callback is never invoked. {END}
-** 
-** {F12916} Every call to [sqlite3_progress_handler()]
-**          overwrites any previously registere progress handler.
-**
-** {F12917} If the progress handler callback is NULL then no progress
-**          handler is invoked.
-**
-** {F12918} If the progress callback returns a result other than 0, then
-**          the behavior is a if [sqlite3_interrupt()] had been called.
 */
 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 
 /*
-** CAPI3REF: Opening A New Database Connection {F12700}
-**
-** These routines open an SQLite database file whose name
-** is given by the filename argument.
-** The filename argument is interpreted as UTF-8
-** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
-** in the native byte order for [sqlite3_open16()].
-** An [sqlite3*] handle is usually returned in *ppDb, even
-** if an error occurs.  The only exception is if SQLite is unable
-** to allocate memory to hold the [sqlite3] object, a NULL will
-** be written into *ppDb instead of a pointer to the [sqlite3] object.
-** If the database is opened (and/or created)
-** successfully, then [SQLITE_OK] is returned.  Otherwise an
-** error code is returned.  The
-** [sqlite3_errmsg()] or [sqlite3_errmsg16()]  routines can be used to obtain
+** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
+**
+** These routines open an SQLite database file whose name is given by the
+** filename argument. The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs.  The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object. If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.  The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
 ** an English language description of the error.
 **
 ** The default encoding for the database will be UTF-8 if
-** [sqlite3_open()] or [sqlite3_open_v2()] is called and
-** UTF-16 in the native byte order if [sqlite3_open16()] is used.
+** sqlite3_open() or sqlite3_open_v2() is called and
+** UTF-16 in the native byte order if sqlite3_open16() is used.
 **
 ** Whether or not an error occurs when it is opened, resources
-** associated with the [sqlite3*] handle should be released by passing it
-** to [sqlite3_close()] when it is no longer required.
+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
 **
-** The [sqlite3_open_v2()] interface works like [sqlite3_open()] 
-** except that it acccepts two additional parameters for additional control
-** over the new database connection.  The flags parameter can be
-** one of:
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection.  The flags parameter can take one of
+** the following three values, optionally combined with the 
+** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
+** and/or [SQLITE_OPEN_PRIVATECACHE] flags:
 **
-** <ol>
-** <li>  [SQLITE_OPEN_READONLY]
-** <li>  [SQLITE_OPEN_READWRITE]
-** <li>  [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
-** </ol>
+** <dl>
+** <dt>[SQLITE_OPEN_READONLY]</dt>
+** <dd>The database is opened in read-only mode.  If the database does not
+** already exist, an error is returned.</dd>
+**
+** <dt>[SQLITE_OPEN_READWRITE]</dt>
+** <dd>The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system.  In either
+** case the database must already exist, otherwise an error is returned.</dd>
+**
+** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
+** <dd>The database is opened for reading and writing, and is creates it if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().</dd>
+** </dl>
+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above or one of the combinations shown above combined
+** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
+** then the behavior is undefined.
 **
-** The first value opens the database read-only. 
-** If the database does not previously exist, an error is returned.
-** The second option opens
-** the database for reading and writing if possible, or reading only if
-** if the file is write protected.  In either case the database
-** must already exist or an error is returned.  The third option
-** opens the database for reading and writing and creates it if it does
-** not already exist.
-** The third options is behavior that is always used for [sqlite3_open()]
-** and [sqlite3_open16()].
-**
-** If the 3rd parameter to [sqlite3_open_v2()] is not one of the
-** combinations shown above then the behavior is undefined.
-**
-** If the filename is ":memory:", then an private
-** in-memory database is created for the connection.  This in-memory
-** database will vanish when the database connection is closed.  Future
-** version of SQLite might make use of additional special filenames
-** that begin with the ":" character.  It is recommended that 
-** when a database filename really does begin with
-** ":" that you prefix the filename with a pathname like "./" to
-** avoid ambiguity.
-**
-** If the filename is an empty string, then a private temporary
+** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time.  If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+** The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
+** eligible to use [shared cache mode], regardless of whether or not shared
+** cache is enabled using [sqlite3_enable_shared_cache()].  The
+** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
+** participate in [shared cache mode] even if it is enabled.
+**
+** If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection.  This in-memory database will vanish when
+** the database connection is closed.  Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** If the filename is an empty string, then a private, temporary
 ** on-disk database will be created.  This private database will be
 ** automatically deleted as soon as the database connection is closed.
 **
 ** The fourth parameter to sqlite3_open_v2() is the name of the
-** [sqlite3_vfs] object that defines the operating system 
-** interface that the new database connection should use.  If the
-** fourth parameter is a NULL pointer then the default [sqlite3_vfs]
-** object is used.
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use.  If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
 **
-** <b>Note to windows users:</b>  The encoding used for the filename argument
-** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever
+** <b>Note to Windows users:</b>  The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
 ** codepage is currently defined.  Filenames containing international
 ** characters must be converted to UTF-8 prior to passing them into
-** [sqlite3_open()] or [sqlite3_open_v2()].
-**
-** INVARIANTS:
-**
-** {F12701} The [sqlite3_open()], [sqlite3_open16()], and
-**          [sqlite3_open_v2()] interfaces create a new
-**          [database connection] associated with
-**          the database file given in their first parameter.
-**
-** {F12702} The filename argument is interpreted as UTF-8
-**          for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
-**          in the native byte order for [sqlite3_open16()].
-**
-** {F12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()], 
-**          or [sqlite3_open_v2()] writes a pointer to a new
-**          [database connection] into *ppDb.
-**
-** {F12704} The [sqlite3_open()], [sqlite3_open16()], and
-**          [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
-**          or an appropriate [error code] on failure.
-**
-** {F12706} The default text encoding for a new database created using
-**          [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
-**
-** {F12707} The default text encoding for a new database created using
-**          [sqlite3_open16()] will be UTF-16.
-**
-** {F12709} The [sqlite3_open(F,D)] interface is equivalent to
-**          [sqlite3_open_v2(F,D,G,0)] where the G parameter is
-**          [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
+** sqlite3_open() or sqlite3_open_v2().
 **
-** {F12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_READONLY] then the database is opened
-**          for reading only.
-**
-** {F12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_READWRITE] then the database is opened
-**          reading and writing if possible, or for reading only if the
-**          file is write protected by the operating system.
-**
-** {F12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
-**          bit value [SQLITE_OPEN_CREATE] and the database does not
-**          previously exist, an error is returned.
-**
-** {F12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_CREATE] and the database does not
-**          previously exist, then an attempt is made to create and
-**          initialize the database.
-**
-** {F12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
-**          or [sqlite3_open_v2()] is ":memory:", then an private,
-**          ephemeral, in-memory database is created for the connection.
-**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
-**          in sqlite3_open_v2()?</todo>
-**
-** {F12719} If the filename is NULL or an empty string, then a private,
-**          ephermeral on-disk database will be created.
-**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
-**          in sqlite3_open_v2()?</todo>
-**
-** {F12721} The [database connection] created by 
-**          [sqlite3_open_v2(F,D,G,V)] will use the
-**          [sqlite3_vfs] object identified by the V parameter, or
-**          the default [sqlite3_vfs] object is V is a NULL pointer.
+** Requirements:
+** [H12701] [H12702] [H12703] [H12704] [H12706] [H12707] [H12709] [H12711]
+** [H12712] [H12713] [H12714] [H12717] [H12719] [H12721] [H12723]
 */
 SQLITE_API int sqlite3_open(
   const char *filename,   /* Database filename (UTF-8) */
@@ -2504,68 +2715,61 @@ SQLITE_API int sqlite3_open_v2(
 );
 
 /*
-** CAPI3REF: Error Codes And Messages {F12800}
+** CAPI3REF: Error Codes And Messages {H12800} <S60200>
 **
-** The sqlite3_errcode() interface returns the numeric
-** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code]
-** for the most recent failed sqlite3_* API call associated
-** with [sqlite3] handle 'db'. If a prior API call failed but the
-** most recent API call succeeded, the return value from sqlite3_errcode()
-** is undefined.
+** The sqlite3_errcode() interface returns the numeric [result code] or
+** [extended result code] for the most recent failed sqlite3_* API call
+** associated with a [database connection]. If a prior API call failed
+** but the most recent API call succeeded, the return value from
+** sqlite3_errcode() is undefined.  The sqlite3_extended_errcode()
+** interface is the same except that it always returns the 
+** [extended result code] even when extended result codes are
+** disabled.
 **
 ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
-** text that describes the error, as either UTF8 or UTF16 respectively.
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
 ** Memory to hold the error message string is managed internally.
-** The application does not need to worry with freeing the result.
+** The application does not need to worry about freeing the result.
 ** However, the error string might be overwritten or deallocated by
 ** subsequent calls to other SQLite interface functions.
 **
-** INVARIANTS:
-**
-** {F12801} The [sqlite3_errcode(D)] interface returns the numeric
-**          [SQLITE_OK | result code] or
-**          [SQLITE_IOERR_READ | extended result code]
-**          for the most recently failed interface call associated
-**          with [database connection] D.
+** When the serialized [threading mode] is in use, it might be the
+** case that a second error occurs on a separate thread in between
+** the time of the first error and the call to these interfaces.
+** When that happens, the second error will be reported since these
+** interfaces always report the most recent result.  To avoid
+** this, each thread can obtain exclusive use of the [database connection] D
+** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
+** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
+** all calls to the interfaces listed here are completed.
 **
-** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
-**          interfaces return English-language text that describes
-**          the error in the mostly recently failed interface call,
-**          encoded as either UTF8 or UTF16 respectively.
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application.  In that case, the
+** error code and message may or may not be set.
 **
-** {F12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
-**          are valid until the next SQLite interface call.
-**
-** {F12808} Calls to API routines that do not return an error code
-**          (example: [sqlite3_data_count()]) do not
-**          change the error code or message returned by
-**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
-**
-** {F12809} Interfaces that are not associated with a specific
-**          [database connection] (examples:
-**          [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
-**          do not change the values returned by
-**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
+** Requirements:
+** [H12801] [H12802] [H12803] [H12807] [H12808] [H12809]
 */
 SQLITE_API int sqlite3_errcode(sqlite3 *db);
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
 SQLITE_API const char *sqlite3_errmsg(sqlite3*);
 SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
 
 /*
-** CAPI3REF: SQL Statement Object {F13000}
+** CAPI3REF: SQL Statement Object {H13000} <H13010>
 ** KEYWORDS: {prepared statement} {prepared statements}
 **
-** An instance of this object represent single SQL statements.  This
-** object is variously known as a "prepared statement" or a 
+** An instance of this object represents a single SQL statement.
+** This object is variously known as a "prepared statement" or a
 ** "compiled SQL statement" or simply as a "statement".
-** 
+**
 ** The life of a statement object goes something like this:
 **
 ** <ol>
 ** <li> Create the object using [sqlite3_prepare_v2()] or a related
 **      function.
-** <li> Bind values to host parameters using
-**      [sqlite3_bind_blob | sqlite3_bind_* interfaces].
+** <li> Bind values to [host parameters] using the sqlite3_bind_*()
+**      interfaces.
 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
 ** <li> Reset the statement using [sqlite3_reset()] then go back
 **      to step 2.  Do this zero or more times.
@@ -2578,7 +2782,7 @@ SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
 typedef struct sqlite3_stmt sqlite3_stmt;
 
 /*
-** CAPI3REF: Run-time Limits {F12760}
+** CAPI3REF: Run-time Limits {H12760} <S20600>
 **
 ** This interface allows the size of various constructs to be limited
 ** on a connection by connection basis.  The first parameter is the
@@ -2588,8 +2792,10 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** new limit for that construct.  The function returns the old limit.
 **
 ** If the new limit is a negative number, the limit is unchanged.
-** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
-** bound set by a compile-time C-preprocess macro named SQLITE_MAX_XYZ.
+** For the limit category of SQLITE_LIMIT_XYZ there is a 
+** [limits | hard upper bound]
+** set by a compile-time C preprocessor macro named 
+** [limits | SQLITE_MAX_XYZ].
 ** (The "_LIMIT_" in the name is changed to "_MAX_".)
 ** Attempts to increase a limit above its hard upper bound are
 ** silently truncated to the hard upper limit.
@@ -2597,55 +2803,42 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** Run time limits are intended for use in applications that manage
 ** both their own internal database and also databases that are controlled
 ** by untrusted external sources.  An example application might be a
-** webbrowser that has its own databases for storing history and
-** separate databases controlled by javascript applications downloaded
-** off the internet.  The internal databases can be given the
+** web browser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet.  The internal databases can be given the
 ** large, default limits.  Databases managed by external sources can
 ** be given much smaller limits designed to prevent a denial of service
-** attach.  Developers might also want to use the [sqlite3_set_authorizer()]
+** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
 ** interface to further control untrusted SQL.  The size of the database
 ** created by an untrusted script can be contained using the
 ** [max_page_count] [PRAGMA].
 **
-** This interface is currently considered experimental and is subject
-** to change or removal without prior notice.
+** New run-time limit categories may be added in future releases.
 **
-** INVARIANTS:
-**
-** {F12762} A successful call to [sqlite3_limit(D,C,V)] where V is
-**          positive changes the
-**          limit on the size of construct C in [database connection] D
-**          to the lessor of V and the hard upper bound on the size
-**          of C that is set at compile-time.
-**
-** {F12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
-**          leaves the state of [database connection] D unchanged.
-**
-** {F12769} A successful call to [sqlite3_limit(D,C,V)] returns the
-**          value of the limit on the size of construct C in
-**          in [database connection] D as it was prior to the call.
+** Requirements:
+** [H12762] [H12766] [H12769]
 */
 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 
 /*
-** CAPI3REF: Run-Time Limit Categories {F12790}
+** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
 ** KEYWORDS: {limit category} {limit categories}
-** 
-** These constants define various aspects of a [database connection]
-** that can be limited in size by calls to [sqlite3_limit()].
-** The meanings of the various limits are as follows:
+**
+** These constants define various performance limits
+** that can be lowered at run-time using [sqlite3_limit()].
+** The synopsis of the meanings of the various limits is shown below.
+** Additional information is available at [limits | Limits in SQLite].
 **
 ** <dl>
 ** <dt>SQLITE_LIMIT_LENGTH</dt>
-** <dd>The maximum size of any
-** string or blob or table row.<dd>
+** <dd>The maximum size of any string or BLOB or table row.<dd>
 **
 ** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
 ** <dd>The maximum length of an SQL statement.</dd>
 **
 ** <dt>SQLITE_LIMIT_COLUMN</dt>
 ** <dd>The maximum number of columns in a table definition or in the
-** result set of a SELECT or the maximum number of columns in an index
+** result set of a [SELECT] or the maximum number of columns in an index
 ** or in an ORDER BY or GROUP BY clause.</dd>
 **
 ** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
@@ -2662,15 +2855,18 @@ SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 ** <dd>The maximum number of arguments on a function.</dd>
 **
 ** <dt>SQLITE_LIMIT_ATTACHED</dt>
-** <dd>The maximum number of attached databases.</dd>
+** <dd>The maximum number of [ATTACH | attached databases].</dd>
 **
 ** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
-** <dd>The maximum length of the pattern argument to the LIKE or
-** GLOB operators.</dd>
+** <dd>The maximum length of the pattern argument to the [LIKE] or
+** [GLOB] operators.</dd>
 **
 ** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
 ** <dd>The maximum number of variables in an SQL statement that can
 ** be bound.</dd>
+**
+** <dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
+** <dd>The maximum depth of recursion for triggers.</dd>
 ** </dl>
 */
 #define SQLITE_LIMIT_LENGTH                    0
@@ -2683,54 +2879,55 @@ SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 #define SQLITE_LIMIT_ATTACHED                  7
 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
 #define SQLITE_LIMIT_VARIABLE_NUMBER           9
+#define SQLITE_LIMIT_TRIGGER_DEPTH            10
 
 /*
-** CAPI3REF: Compiling An SQL Statement {F13010}
+** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
+** KEYWORDS: {SQL statement compiler}
 **
 ** To execute an SQL query, it must first be compiled into a byte-code
-** program using one of these routines. 
+** program using one of these routines.
+**
+** The first argument, "db", is a [database connection] obtained from a
+** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
+** [sqlite3_open16()].  The database connection must not have been closed.
 **
-** The first argument "db" is an [database connection] 
-** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()]
-** or [sqlite3_open16()]. 
-** The second argument "zSql" is the statement to be compiled, encoded
+** The second argument, "zSql", is the statement to be compiled, encoded
 ** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
-** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
-** use UTF-16. {END}
-**
-** If the nByte argument is less
-** than zero, then zSql is read up to the first zero terminator.
-** If nByte is non-negative, then it is the maximum number of 
-** bytes read from zSql.  When nByte is non-negative, the
-** zSql string ends at either the first '\000' or '\u0000' character or 
+** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
+** use UTF-16.
+**
+** If the nByte argument is less than zero, then zSql is read up to the
+** first zero terminator. If nByte is non-negative, then it is the maximum
+** number of  bytes read from zSql.  When nByte is non-negative, the
+** zSql string ends at either the first '\000' or '\u0000' character or
 ** the nByte-th byte, whichever comes first. If the caller knows
 ** that the supplied string is nul-terminated, then there is a small
-** performance advantage to be had by passing an nByte parameter that 
-** is equal to the number of bytes in the input string <i>including</i> 
-** the nul-terminator bytes.{END}
+** performance advantage to be gained by passing an nByte parameter that
+** is equal to the number of bytes in the input string <i>including</i>
+** the nul-terminator bytes.
 **
-** *pzTail is made to point to the first byte past the end of the
-** first SQL statement in zSql.  These routines only compiles the first
-** statement in zSql, so *pzTail is left pointing to what remains
-** uncompiled.
+** If pzTail is not NULL then *pzTail is made to point to the first byte
+** past the end of the first SQL statement in zSql.  These routines only
+** compile the first statement in zSql, so *pzTail is left pointing to
+** what remains uncompiled.
 **
 ** *ppStmt is left pointing to a compiled [prepared statement] that can be
-** executed using [sqlite3_step()].  Or if there is an error, *ppStmt is
-** set to NULL.  If the input text contains no SQL (if the input
-** is and empty string or a comment) then *ppStmt is set to NULL.
-** {U13018} The calling procedure is responsible for deleting the
-** compiled SQL statement
-** using [sqlite3_finalize()] after it has finished with it.
+** executed using [sqlite3_step()].  If there is an error, *ppStmt is set
+** to NULL.  If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
+** ppStmt may not be NULL.
 **
-** On success, [SQLITE_OK] is returned.  Otherwise an 
-** [error code] is returned.
+** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
 **
 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
 ** recommended for all new programs. The two older interfaces are retained
 ** for backwards compatibility, but their use is discouraged.
 ** In the "v2" interfaces, the prepared statement
-** that is returned (the [sqlite3_stmt] object) contains a copy of the 
-** original SQL text. {END} This causes the [sqlite3_step()] interface to
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
 ** behave a differently in two ways:
 **
 ** <ol>
@@ -2739,60 +2936,25 @@ SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
 ** statement and try to run it again.  If the schema has changed in
 ** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, 
-** [SQLITE_SCHEMA] is now a fatal error.  Calling
-** [sqlite3_prepare_v2()] again will not make the
+** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
+** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
 ** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return. {END}
+** of the parsing error that results in an [SQLITE_SCHEMA] return.
 ** </li>
 **
 ** <li>
-** When an error occurs, 
-** [sqlite3_step()] will return one of the detailed 
-** [error codes] or [extended error codes]. 
-** The legacy behavior was that [sqlite3_step()] would only return a generic
-** [SQLITE_ERROR] result code and you would have to make a second call to
-** [sqlite3_reset()] in order to find the underlying cause of the problem.
-** With the "v2" prepare interfaces, the underlying reason for the error is
-** returned immediately.
+** When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes].  The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and you would have to make a second call to [sqlite3_reset()] in order
+** to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
 ** </li>
 ** </ol>
 **
-** INVARIANTS:
-**
-** {F13011} The [sqlite3_prepare(db,zSql,...)] and
-**          [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
-**          text in their zSql parameter as UTF-8.
-**
-** {F13012} The [sqlite3_prepare16(db,zSql,...)] and
-**          [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
-**          text in their zSql parameter as UTF-16 in the native byte order.
-**
-** {F13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is less than zero, then SQL text is
-**          read from zSql is read up to the first zero terminator.
-**
-** {F13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is non-negative, then at most nBytes bytes
-**          SQL text is read from zSql.
-**
-** {F13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
-**          if the zSql input text contains more than one SQL statement
-**          and pzTail is not NULL, then *pzTail is made to point to the
-**          first byte past the end of the first SQL statement in zSql.
-**          <todo>What does *pzTail point to if there is one statement?</todo>
+** Requirements:
+** [H13011] [H13012] [H13013] [H13014] [H13015] [H13016] [H13019] [H13021]
 **
-** {F13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
-**          or one of its variants writes into *ppStmt a pointer to a new
-**          [prepared statement] or a pointer to NULL
-**          if zSql contains nothing other than whitespace or comments. 
-**
-** {F13019} The [sqlite3_prepare_v2()] interface and its variants return
-**          [SQLITE_OK] or an appropriate [error code] upon failure.
-**
-** {F13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
-**          variants returns an error (any value other than [SQLITE_OK])
-**          it first sets *ppStmt to NULL.
 */
 SQLITE_API int sqlite3_prepare(
   sqlite3 *db,            /* Database handle */
@@ -2824,85 +2986,78 @@ SQLITE_API int sqlite3_prepare16_v2(
 );
 
 /*
-** CAPIREF: Retrieving Statement SQL {F13100}
-**
-** This intereface can be used to retrieve a saved copy of the original
-** SQL text used to create a [prepared statement].
-**
-** INVARIANTS:
+** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
 **
-** {F13101} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare_v2()] or
-**          [sqlite3_prepare16_v2()],
-**          then [sqlite3_sql()] function returns a pointer to a
-**          zero-terminated string containing a UTF-8 rendering
-**          of the original SQL statement.
+** This interface can be used to retrieve a saved copy of the original
+** SQL text used to create a [prepared statement] if that statement was
+** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
 **
-** {F13102} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare()] or
-**          [sqlite3_prepare16()],
-**          then [sqlite3_sql()] function returns a NULL pointer.
-**
-** {F13103} The string returned by [sqlite3_sql(S)] is valid until the
-**          [prepared statement] S is deleted using [sqlite3_finalize(S)].
+** Requirements:
+** [H13101] [H13102] [H13103]
 */
 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF:  Dynamically Typed Value Object  {F15000}
+** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
 **
 ** SQLite uses the sqlite3_value object to represent all values
-** that can be stored in a database table.
-** SQLite uses dynamic typing for the values it stores.  
-** Values stored in sqlite3_value objects can be
-** be integers, floating point values, strings, BLOBs, or NULL.
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores. Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
 **
 ** An sqlite3_value object may be either "protected" or "unprotected".
 ** Some interfaces require a protected sqlite3_value.  Other interfaces
 ** will accept either a protected or an unprotected sqlite3_value.
-** Every interface that accepts sqlite3_value arguments specifies 
+** Every interface that accepts sqlite3_value arguments specifies
 ** whether or not it requires a protected sqlite3_value.
 **
 ** The terms "protected" and "unprotected" refer to whether or not
 ** a mutex is held.  A internal mutex is held for a protected
 ** sqlite3_value object but no mutex is held for an unprotected
 ** sqlite3_value object.  If SQLite is compiled to be single-threaded
-** (with SQLITE_THREADSAFE=0 and with [sqlite3_threadsafe()] returning 0)
-** then there is no distinction between
-** protected and unprotected sqlite3_value objects and they can be
-** used interchangable.  However, for maximum code portability it
-** is recommended that applications make the distinction between
-** between protected and unprotected sqlite3_value objects even if
-** they are single threaded.
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes 
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably.  However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between between protected and unprotected
+** sqlite3_value objects even when not strictly required.
 **
 ** The sqlite3_value objects that are passed as parameters into the
-** implementation of application-defined SQL functions are protected.
+** implementation of [application-defined SQL functions] are protected.
 ** The sqlite3_value object returned by
 ** [sqlite3_column_value()] is unprotected.
 ** Unprotected sqlite3_value objects may only be used with
-** [sqlite3_result_value()] and [sqlite3_bind_value()].  All other
-** interfaces that use sqlite3_value require protected sqlite3_value objects.
+** [sqlite3_result_value()] and [sqlite3_bind_value()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
 */
 typedef struct Mem sqlite3_value;
 
 /*
-** CAPI3REF:  SQL Function Context Object {F16001}
+** CAPI3REF: SQL Function Context Object {H16001} <S20200>
 **
 ** The context in which an SQL function executes is stored in an
-** sqlite3_context object.  A pointer to an sqlite3_context
-** object is always first parameter to application-defined SQL functions.
+** sqlite3_context object.  A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
 */
 typedef struct sqlite3_context sqlite3_context;
 
 /*
-** CAPI3REF:  Binding Values To Prepared Statements {F13500}
+** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
 **
-** In the SQL strings input to [sqlite3_prepare_v2()] and its
-** variants, literals may be replace by a parameter in one
-** of these forms:
+** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a [parameter] that matches one of following
+** templates:
 **
 ** <ul>
 ** <li>  ?
@@ -2912,33 +3067,32 @@ typedef struct sqlite3_context sqlite3_context;
 ** <li>  $VVV
 ** </ul>
 **
-** In the parameter forms shown above NNN is an integer literal,
-** VVV alpha-numeric parameter name.
-** The values of these parameters (also called "host parameter names"
-** or "SQL parameters")
+** In the templates above, NNN represents an integer literal,
+** and VVV represents an alphanumeric identifer.  The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
-** The first argument to the sqlite3_bind_*() routines always
-** is a pointer to the [sqlite3_stmt] object returned from
-** [sqlite3_prepare_v2()] or its variants. The second
-** argument is the index of the parameter to be set. The
-** first parameter has an index of 1.  When the same named
-** parameter is used more than once, second and subsequent
-** occurrences have the same index as the first occurrence. 
+** The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** The second argument is the index of the SQL parameter to be set.
+** The leftmost SQL parameter has an index of 1.  When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
 ** The index for named parameters can be looked up using the
-** [sqlite3_bind_parameter_name()] API if desired.  The index
+** [sqlite3_bind_parameter_index()] API if desired.  The index
 ** for "?NNN" parameters is the value of NNN.
-** The NNN value must be between 1 and the compile-time
-** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999).
+** The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
 **
 ** The third argument is the value to bind to the parameter.
 **
-** In those
-** routines that have a fourth argument, its value is the number of bytes
-** in the parameter.  To be clear: the value is the number of <u>bytes</u>
-** in the value, not the number of characters. 
+** In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter.  To be clear: the value is the
+** number of <u>bytes</u> in the value, not the number of characters.
 ** If the fourth parameter is negative, the length of the string is
-** number of bytes up to the first zero terminator.
+** the number of bytes up to the first zero terminator.
 **
 ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
@@ -2950,12 +3104,12 @@ typedef struct sqlite3_context sqlite3_context;
 ** the sqlite3_bind_*() routine returns.
 **
 ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
-** is filled with zeros.  A zeroblob uses a fixed amount of memory
-** (just an integer to hold it size) while it is being processed.
-** Zeroblobs are intended to serve as place-holders for BLOBs whose
-** content is later written using 
-** [sqlite3_blob_open | increment BLOB I/O] routines. A negative
-** value for the zeroblob results in a zero-length BLOB.
+** is filled with zeroes.  A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** A negative value for the zeroblob results in a zero-length BLOB.
 **
 ** The sqlite3_bind_*() routines must be called after
 ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
@@ -2965,7 +3119,7 @@ typedef struct sqlite3_context sqlite3_context;
 **
 ** These routines return [SQLITE_OK] on success or an error code if
 ** anything goes wrong.  [SQLITE_RANGE] is returned if the parameter
-** index is out of range.  [SQLITE_NOMEM] is returned if malloc fails.
+** index is out of range.  [SQLITE_NOMEM] is returned if malloc() fails.
 ** [SQLITE_MISUSE] might be returned if these routines are called on a
 ** virtual machine that is the wrong state or which has already been finalized.
 ** Detection of misuse is unreliable.  Applications should not depend
@@ -2974,81 +3128,12 @@ typedef struct sqlite3_context sqlite3_context;
 ** panic rather than return SQLITE_MISUSE.
 **
 ** See also: [sqlite3_bind_parameter_count()],
-** [sqlite3_bind_parameter_name()], and
-** [sqlite3_bind_parameter_index()].
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
+** Requirements:
+** [H13506] [H13509] [H13512] [H13515] [H13518] [H13521] [H13524] [H13527]
+** [H13530] [H13533] [H13536] [H13539] [H13542] [H13545] [H13548] [H13551]
 **
-** {F13506} The [sqlite3_prepare | SQL statement compiler] recognizes
-**          tokens of the forms "?", "?NNN", "$VVV", ":VVV", and "@VVV"
-**          as SQL parameters, where NNN is any sequence of one or more
-**          digits and where VVV is any sequence of one or more 
-**          alphanumeric characters or "::" optionally followed by
-**          a string containing no spaces and contained within parentheses.
-**
-** {F13509} The initial value of an SQL parameter is NULL.
-**
-** {F13512} The index of an "?" SQL parameter is one larger than the
-**          largest index of SQL parameter to the left, or 1 if
-**          the "?" is the leftmost SQL parameter.
-**
-** {F13515} The index of an "?NNN" SQL parameter is the integer NNN.
-**
-** {F13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
-**          the same as the index of leftmost occurances of the same
-**          parameter, or one more than the largest index over all
-**          parameters to the left if this is the first occurrance
-**          of this parameter, or 1 if this is the leftmost parameter.
-**
-** {F13521} The [sqlite3_prepare | SQL statement compiler] fail with
-**          an [SQLITE_RANGE] error if the index of an SQL parameter
-**          is less than 1 or greater than SQLITE_MAX_VARIABLE_NUMBER.
-**
-** {F13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
-**          associate the value V with all SQL parameters having an
-**          index of N in the [prepared statement] S.
-**
-** {F13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
-**          override prior calls with the same values of S and N.
-**
-** {F13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
-**          persist across calls to [sqlite3_reset(S)].
-**
-** {F13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
-**          bytes of the blob or string pointed to by V, when L
-**          is non-negative.
-**
-** {F13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
-**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
-**          from V through the first zero character when L is negative.
-**
-** {F13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
-**          constant [SQLITE_STATIC], SQLite assumes that the value V
-**          is held in static unmanaged space that will not change
-**          during the lifetime of the binding.
-**
-** {F13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
-**          constant [SQLITE_TRANSIENT], the routine makes a 
-**          private copy of V value before it returns.
-**
-** {F13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
-**          a function, SQLite invokes that function to destroy the
-**          V value after it has finished using the V value.
-**
-** {F13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
-**          is a blob of L bytes, or a zero-length blob if L is negative.
-**
-** {F13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
-**          be either a [protected sqlite3_value] object or an
-**          [unprotected sqlite3_value] object.
 */
 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
@@ -3061,49 +3146,46 @@ SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
 
 /*
-** CAPI3REF: Number Of SQL Parameters {F13600}
+** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
 **
-** This routine can be used to find the number of SQL parameters
-** in a prepared statement.  SQL parameters are tokens of the
+** This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement].  SQL parameters are tokens of the
 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
-** place-holders for values that are [sqlite3_bind_blob | bound]
+** placeholders for values that are [sqlite3_bind_blob | bound]
 ** to the parameters at a later time.
 **
-** This routine actually returns the index of the largest parameter.
-** For all forms except ?NNN, this will correspond to the number of
-** unique parameters.  If parameters of the ?NNN are used, there may
-** be gaps in the list.
+** This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters.  If parameters of the ?NNN are used,
+** there may be gaps in the list.
 **
 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
 ** [sqlite3_bind_parameter_name()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13601} The [sqlite3_bind_parameter_count(S)] interface returns
-**          the largest index of all SQL parameters in the
-**          [prepared statement] S, or 0 if S
-**          contains no SQL parameters.
+** Requirements:
+** [H13601]
 */
 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Name Of A Host Parameter {F13620}
+** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
 **
 ** This routine returns a pointer to the name of the n-th
-** SQL parameter in a [prepared statement].
+** [SQL parameter] in a [prepared statement].
 ** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
 ** respectively.
 ** In other words, the initial ":" or "$" or "@" or "?"
 ** is included as part of the name.
-** Parameters of the form "?" without a following integer have no name.
+** Parameters of the form "?" without a following integer have no name
+** and are also referred to as "anonymous parameters".
 **
 ** The first host parameter has an index of 1, not 0.
 **
 ** If the value n is out of range or if the n-th parameter is
 ** nameless, then NULL is returned.  The returned string is
-** always in the UTF-8 encoding even if the named parameter was
+** always in UTF-8 encoding even if the named parameter was
 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
 ** [sqlite3_prepare16_v2()].
 **
@@ -3111,18 +3193,13 @@ SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
 ** [sqlite3_bind_parameter_count()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
-**          a UTF-8 rendering of the name of the SQL parameter in
-**          [prepared statement] S having index N, or
-**          NULL if there is no SQL parameter with index N or if the
-**          parameter with index N is an anonymous parameter "?".
+** Requirements:
+** [H13621]
 */
 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 
 /*
-** CAPI3REF: Index Of A Parameter With A Given Name {F13640}
+** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
 **
 ** Return the index of an SQL parameter given its name.  The
 ** index value returned is suitable for use as the second
@@ -3135,64 +3212,49 @@ SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 ** [sqlite3_bind_parameter_count()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
-**          the index of SQL parameter in [prepared statement]
-**          S whose name matches the UTF-8 string N, or 0 if there is
-**          no match.
+** Requirements:
+** [H13641]
 */
 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
 
 /*
-** CAPI3REF: Reset All Bindings On A Prepared Statement {F13660}
-**
-** Contrary to the intuition of many, [sqlite3_reset()] does not
-** reset the [sqlite3_bind_blob | bindings] on a 
-** [prepared statement].  Use this routine to
-** reset all host parameters to NULL.
+** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
 **
-** INVARIANTS:
+** Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** Use this routine to reset all host parameters to NULL.
 **
-** {F13661} The [sqlite3_clear_bindings(S)] interface resets all
-**          SQL parameter bindings in [prepared statement] S
-**          back to NULL.
+** Requirements:
+** [H13661]
 */
 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number Of Columns In A Result Set {F13710}
+** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
 **
-** Return the number of columns in the result set returned by the 
-** [prepared statement]. This routine returns 0
-** if pStmt is an SQL statement that does not return data (for 
-** example an UPDATE).
+** Return the number of columns in the result set returned by the
+** [prepared statement]. This routine returns 0 if pStmt is an SQL
+** statement that does not return data (for example an [UPDATE]).
 **
-** INVARIANTS:
-**
-** {F13711} The [sqlite3_column_count(S)] interface returns the number of
-**          columns in the result set generated by the
-**          [prepared statement] S, or 0 if S does not generate
-**          a result set.
+** Requirements:
+** [H13711]
 */
 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Column Names In A Result Set {F13720}
+** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
 **
 ** These routines return the name assigned to a particular column
-** in the result set of a SELECT statement.  The sqlite3_column_name()
-** interface returns a pointer to a zero-terminated UTF8 string
+** in the result set of a [SELECT] statement.  The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
-** UTF16 string.  The first parameter is the
-** [prepared statement] that implements the SELECT statement.
-** The second parameter is the column number.  The left-most column is
-** number 0.
+** UTF-16 string.  The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. The second parameter is the
+** column number.  The leftmost column is number 0.
 **
-** The returned string pointer is valid until either the 
-** [prepared statement] is destroyed by [sqlite3_finalize()]
-** or until the next call sqlite3_column_name() or sqlite3_column_name16()
-** on the same column.
+** The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
 **
 ** If sqlite3_malloc() fails during the processing of either routine
 ** (for example during a conversion from UTF-8 to UTF-16) then a
@@ -3203,139 +3265,56 @@ SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 ** then the name of the column is unspecified and may change from
 ** one release of SQLite to the next.
 **
-** INVARIANTS:
-**
-** {F13721} A successful invocation of the [sqlite3_column_name(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-8 string.
-**
-** {F13723} A successful invocation of the [sqlite3_column_name16(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-16 string in the native byte order.
-**
-** {F13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
-**          interfaces return a NULL pointer if they are unable to
-**          allocate memory memory to hold there normal return strings.
-**
-** {F13725} If the N parameter to [sqlite3_column_name(S,N)] or
-**          [sqlite3_column_name16(S,N)] is out of range, then the
-**          interfaces returns a NULL pointer.
-** 
-** {F13726} The strings returned by [sqlite3_column_name(S,N)] and
-**          [sqlite3_column_name16(S,N)] are valid until the next
-**          call to either routine with the same S and N parameters
-**          or until [sqlite3_finalize(S)] is called.
-**
-** {F13727} When a result column of a [SELECT] statement contains
-**          an AS clause, the name of that column is the indentifier
-**          to the right of the AS keyword.
+** Requirements:
+** [H13721] [H13723] [H13724] [H13725] [H13726] [H13727]
 */
 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
 
 /*
-** CAPI3REF: Source Of Data In A Query Result {F13740}
+** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
 **
 ** These routines provide a means to determine what column of what
-** table in which database a result of a SELECT statement comes from.
+** table in which database a result of a [SELECT] statement comes from.
 ** The name of the database or table or column can be returned as
-** either a UTF8 or UTF16 string.  The _database_ routines return
+** either a UTF-8 or UTF-16 string.  The _database_ routines return
 ** the database name, the _table_ routines return the table name, and
 ** the origin_ routines return the column name.
-** The returned string is valid until
-** the [prepared statement] is destroyed using
-** [sqlite3_finalize()] or until the same information is requested
+** The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the same information is requested
 ** again in a different encoding.
 **
 ** The names returned are the original un-aliased names of the
 ** database, table, and column.
 **
 ** The first argument to the following calls is a [prepared statement].
-** These functions return information about the Nth column returned by 
+** These functions return information about the Nth column returned by
 ** the statement, where N is the second function argument.
 **
-** If the Nth column returned by the statement is an expression
-** or subquery and is not a column value, then all of these functions
-** return NULL.  These routine might also return NULL if a memory
-** allocation error occurs.  Otherwise, they return the 
-** name of the attached database, table and column that query result
-** column was extracted from.
+** If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL.  These routine might also return NULL if a memory allocation error
+** occurs.  Otherwise, they return the name of the attached database, table
+** and column that query result column was extracted from.
 **
 ** As with all other SQLite APIs, those postfixed with "16" return
 ** UTF-16 encoded strings, the other functions return UTF-8. {END}
 **
-** These APIs are only available if the library was compiled with the 
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 **
-** {U13751}
+** {A13751}
 ** If two or more threads call one or more of these routines against the same
 ** prepared statement and column at the same time then the results are
 ** undefined.
 **
-** INVARIANTS:
-**
-** {F13741} The [sqlite3_column_database_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13742} The [sqlite3_column_database_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13743} The [sqlite3_column_table_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13744} The [sqlite3_column_table_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13745} The [sqlite3_column_origin_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13748} The return values from
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          are valid
-**          for the lifetime of the [prepared statement]
-**          or until the encoding is changed by another metadata
-**          interface call for the same prepared statement and column.
-**
-** LIMITATIONS:
-**
-** {U13751} If two or more threads call one or more
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          the same [prepared statement] and result column
-**          at the same time then the results are undefined.
+** Requirements:
+** [H13741] [H13742] [H13743] [H13744] [H13745] [H13746] [H13748]
+**
+** If two or more threads call one or more
+** [sqlite3_column_database_name | column metadata interfaces]
+** for the same [prepared statement] and result column
+** at the same time then the results are undefined.
 */
 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
@@ -3345,26 +3324,26 @@ SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 
 /*
-** CAPI3REF: Declared Datatype Of A Query Result {F13760}
+** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
 **
-** The first parameter is a [prepared statement]. 
-** If this statement is a SELECT statement and the Nth column of the 
-** returned result set of that SELECT is a table column (not an
+** The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
 ** expression or subquery) then the declared type of the table
 ** column is returned.  If the Nth column of the result set is an
 ** expression or subquery, then a NULL pointer is returned.
-** The returned string is always UTF-8 encoded.  {END} 
-** For example, in the database schema:
+** The returned string is always UTF-8 encoded. {END}
+**
+** For example, given the database schema:
 **
 ** CREATE TABLE t1(c1 VARIANT);
 **
-** And the following statement compiled:
+** and the following statement to be compiled:
 **
 ** SELECT c1 + 1, c1 FROM t1;
 **
-** Then this routine would return the string "VARIANT" for the second
-** result column (i==1), and a NULL pointer for the first result column
-** (i==0).
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).
 **
 ** SQLite uses dynamic run-time typing.  So just because a column
 ** is declared to contain a particular type does not mean that the
@@ -3373,57 +3352,36 @@ SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 ** is associated with individual values, not with the containers
 ** used to hold those values.
 **
-** INVARIANTS:
-**
-** {F13761}  A successful call to [sqlite3_column_decltype(S,N)]
-**           returns a zero-terminated UTF-8 string containing the
-**           the declared datatype of the table column that appears
-**           as the Nth column (numbered from 0) of the result set to the
-**           [prepared statement] S.
-**
-** {F13762}  A successful call to [sqlite3_column_decltype16(S,N)]
-**           returns a zero-terminated UTF-16 native byte order string
-**           containing the declared datatype of the table column that appears
-**           as the Nth column (numbered from 0) of the result set to the
-**           [prepared statement] S.
-**
-** {F13763}  If N is less than 0 or N is greater than or equal to
-**           the number of columns in [prepared statement] S
-**           or if the Nth column of S is an expression or subquery rather
-**           than a table column or if a memory allocation failure
-**           occurs during encoding conversions, then
-**           calls to [sqlite3_column_decltype(S,N)] or
-**           [sqlite3_column_decltype16(S,N)] return NULL.
+** Requirements:
+** [H13761] [H13762] [H13763]
 */
 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 
-/* 
-** CAPI3REF:  Evaluate An SQL Statement {F13200}
+/*
+** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
 **
-** After an [prepared statement] has been prepared with a call
-** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of
-** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()],
-** then this function must be called one or more times to evaluate the 
-** statement.
+** After a [prepared statement] has been prepared using either
+** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
 **
-** The details of the behavior of this sqlite3_step() interface depend
+** The details of the behavior of the sqlite3_step() interface depend
 ** on whether the statement was prepared using the newer "v2" interface
 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
 ** new "v2" interface is recommended for new applications but the legacy
 ** interface will continue to be supported.
 **
-** In the legacy interface, the return value will be either [SQLITE_BUSY], 
+** In the legacy interface, the return value will be either [SQLITE_BUSY],
 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
-** With the "v2" interface, any of the other [SQLITE_OK | result code]
-** or [SQLITE_IOERR_READ | extended result code] might be returned as
-** well.
+** With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
 **
 ** [SQLITE_BUSY] means that the database engine was unable to acquire the
-** database locks it needs to do its job.  If the statement is a COMMIT
+** database locks it needs to do its job.  If the statement is a [COMMIT]
 ** or occurs outside of an explicit transaction, then you can retry the
-** statement.  If the statement is not a COMMIT and occurs within a
+** statement.  If the statement is not a [COMMIT] and occurs within a
 ** explicit transaction then you should rollback the transaction before
 ** continuing.
 **
@@ -3432,16 +3390,15 @@ SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 ** machine without first calling [sqlite3_reset()] to reset the virtual
 ** machine back to its initial state.
 **
-** If the SQL statement being executed returns any data, then 
-** [SQLITE_ROW] is returned each time a new row of data is ready
-** for processing by the caller. The values may be accessed using
-** the [sqlite3_column_int | column access functions].
+** If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
 ** sqlite3_step() is called again to retrieve the next row of data.
-** 
+**
 ** [SQLITE_ERROR] means that a run-time error (such as a constraint
 ** violation) has occurred.  sqlite3_step() should not be called again on
 ** the VM. More information may be found by calling [sqlite3_errmsg()].
-** With the legacy interface, a more specific error code (example:
+** With the legacy interface, a more specific error code (for example,
 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
 ** can be obtained by calling [sqlite3_reset()] on the
 ** [prepared statement].  In the "v2" interface,
@@ -3449,80 +3406,43 @@ SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 **
 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
 ** Perhaps it was called on a [prepared statement] that has
-** already been [sqlite3_finalize | finalized] or on one that had 
+** already been [sqlite3_finalize | finalized] or on one that had
 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
 ** be the case that the same database connection is being used by two or
 ** more threads at the same moment in time.
 **
-** <b>Goofy Interface Alert:</b>
-** In the legacy interface, 
-** the sqlite3_step() API always returns a generic error code,
-** [SQLITE_ERROR], following any error other than [SQLITE_BUSY]
-** and [SQLITE_MISUSE].  You must call [sqlite3_reset()] or
-** [sqlite3_finalize()] in order to find one of the specific
-** [error codes] that better describes the error.
+** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
 ** We admit that this is a goofy design.  The problem has been fixed
 ** with the "v2" interface.  If you prepare all of your SQL statements
 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
-** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the 
-** more specific [error codes] are returned directly
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
 ** by sqlite3_step().  The use of the "v2" interface is recommended.
 **
-** INVARIANTS:
-**
-** {F13202}  If [prepared statement] S is ready to be
-**           run, then [sqlite3_step(S)] advances that prepared statement
-**           until to completion or until it is ready to return another
-**           row of the result set or an interrupt or run-time error occurs.
-**
-** {F15304}  When a call to [sqlite3_step(S)] causes the 
-**           [prepared statement] S to run to completion,
-**           the function returns [SQLITE_DONE].
-**
-** {F15306}  When a call to [sqlite3_step(S)] stops because it is ready
-**           to return another row of the result set, it returns
-**           [SQLITE_ROW].
-**
-** {F15308}  If a call to [sqlite3_step(S)] encounters an
-**           [sqlite3_interrupt|interrupt] or a run-time error,
-**           it returns an appropraite error code that is not one of
-**           [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
-**
-** {F15310}  If an [sqlite3_interrupt|interrupt] or run-time error
-**           occurs during a call to [sqlite3_step(S)]
-**           for a [prepared statement] S created using
-**           legacy interfaces [sqlite3_prepare()] or
-**           [sqlite3_prepare16()] then the function returns either
-**           [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
+** Requirements:
+** [H13202] [H15304] [H15306] [H15308] [H15310]
 */
 SQLITE_API int sqlite3_step(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number of columns in a result set {F13770}
-**
-** Return the number of values in the current row of the result set.
+** CAPI3REF: Number of columns in a result set {H13770} <S10700>
 **
-** INVARIANTS:
+** Returns the number of values in the current row of the result set.
 **
-** {F13771}  After a call to [sqlite3_step(S)] that returns
-**           [SQLITE_ROW], the [sqlite3_data_count(S)] routine
-**           will return the same value as the
-**           [sqlite3_column_count(S)] function.
-**
-** {F13772}  After [sqlite3_step(S)] has returned any value other than
-**           [SQLITE_ROW] or before [sqlite3_step(S)] has been 
-**           called on the [prepared statement] for
-**           the first time since it was [sqlite3_prepare|prepared]
-**           or [sqlite3_reset|reset], the [sqlite3_data_count(S)]
-**           routine returns zero.
+** Requirements:
+** [H13771] [H13772]
 */
 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Fundamental Datatypes {F10265}
+** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
 ** KEYWORDS: SQLITE_TEXT
 **
-** {F10266}Every value in SQLite has one of five fundamental datatypes:
+** {H10266} Every value in SQLite has one of five fundamental datatypes:
 **
 ** <ul>
 ** <li> 64-bit signed integer
@@ -3536,7 +3456,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
 ** for a completely different meaning.  Software that links against both
-** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
 ** SQLITE_TEXT.
 */
 #define SQLITE_INTEGER  1
@@ -3551,33 +3471,31 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 #define SQLITE3_TEXT     3
 
 /*
-** CAPI3REF: Results Values From A Query {F13800}
+** CAPI3REF: Result Values From A Query {H13800} <S10700>
+** KEYWORDS: {column access functions}
 **
 ** These routines form the "result set query" interface.
 **
-** These routines return information about
-** a single column of the current result row of a query.  In every
-** case the first argument is a pointer to the 
-** [prepared statement] that is being
-** evaluated (the [sqlite3_stmt*] that was returned from 
-** [sqlite3_prepare_v2()] or one of its variants) and
-** the second argument is the index of the column for which information 
-** should be returned.  The left-most column of the result set
-** has an index of 0.
-**
-** If the SQL statement is not currently point to a valid row, or if the
-** the column index is out of range, the result is undefined. 
+** These routines return information about a single column of the current
+** result row of a query.  In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned.  The leftmost column of the result set has the index 0.
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
 ** These routines may only be called when the most recent call to
 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
-** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently.
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
 ** If any of these routines are called after [sqlite3_reset()] or
 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
 ** something other than [SQLITE_ROW], the results are undefined.
 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
 ** are called from a different thread while any of these routines
-** are pending, then the results are undefined.  
+** are pending, then the results are undefined.
 **
-** The sqlite3_column_type() routine returns 
+** The sqlite3_column_type() routine returns the
 ** [SQLITE_INTEGER | datatype code] for the initial data type
 ** of the result column.  The returned value is one of [SQLITE_INTEGER],
 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
@@ -3587,7 +3505,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** versions of SQLite may change the behavior of sqlite3_column_type()
 ** following a type conversion.
 **
-** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 
+** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
 ** routine returns the number of bytes in that BLOB or string.
 ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
 ** the string to UTF-8 and then returns the number of bytes.
@@ -3600,11 +3518,11 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  The return
-** value from sqlite3_column_blob() for a zero-length blob is an arbitrary
+** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
 ** pointer, possibly even a NULL pointer.
 **
 ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.  
+** but leaves the result in UTF-16 in native byte order instead of UTF-8.
 ** The zero terminator is not included in this count.
 **
 ** The object returned by [sqlite3_column_value()] is an
@@ -3612,15 +3530,14 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
 ** If the [unprotected sqlite3_value] object returned by
 ** [sqlite3_column_value()] is used in any other way, including calls
-** to routines like 
-** [sqlite3_value_int()], [sqlite3_value_text()], or [sqlite3_value_bytes()],
-** then the behavior is undefined.
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], then the behavior is undefined.
 **
 ** These routines attempt to convert the value where appropriate.  For
 ** example, if the internal representation is FLOAT and a text result
-** is requested, [sqlite3_snprintf()] is used internally to do the conversion
-** automatically.  The following table details the conversions that
-** are applied:
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically.  The following table details the conversions
+** that are applied:
 **
 ** <blockquote>
 ** <table border="1">
@@ -3632,7 +3549,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** <tr><td>  NULL    <td>   BLOB    <td> Result is NULL pointer
 ** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
 ** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
-** <tr><td> INTEGER  <td>   BLOB    <td> Same as for INTEGER->TEXT
+** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
 ** <tr><td>  FLOAT   <td> INTEGER   <td> Convert from float to integer
 ** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
 ** <tr><td>  FLOAT   <td>   BLOB    <td> Same as FLOAT->TEXT
@@ -3647,57 +3564,56 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** The table above makes reference to standard C library functions atoi()
 ** and atof().  SQLite does not really use these functions.  It has its
-** on equavalent internal routines.  The atoi() and atof() names are
+** own equivalent internal routines.  The atoi() and atof() names are
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
 ** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
-** sqlite3_column_text16() may be invalidated. 
+** sqlite3_column_text16() may be invalidated.
 ** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** <ul>
-** <li><p>  The initial content is a BLOB and sqlite3_column_text() 
-**          or sqlite3_column_text16() is called.  A zero-terminator might
-**          need to be added to the string.</p></li>
-**
-** <li><p>  The initial content is UTF-8 text and sqlite3_column_bytes16() or
-**          sqlite3_column_text16() is called.  The content must be converted
-**          to UTF-16.</p></li>
-**
-** <li><p>  The initial content is UTF-16 text and sqlite3_column_bytes() or
-**          sqlite3_column_text() is called.  The content must be converted
-**          to UTF-8.</p></li>
+** <li> The initial content is a BLOB and sqlite3_column_text() or
+**      sqlite3_column_text16() is called.  A zero-terminator might
+**      need to be added to the string.</li>
+** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
+**      sqlite3_column_text16() is called.  The content must be converted
+**      to UTF-16.</li>
+** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
+**      sqlite3_column_text() is called.  The content must be converted
+**      to UTF-8.</li>
 ** </ul>
 **
 ** Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
 ** that the prior pointer points to will have been modified.  Other kinds
-** of conversion are done in place when it is possible, but sometime it is
-** not possible and in those cases prior pointers are invalidated.  
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
 **
 ** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
-**  <ul>
+** <ul>
 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
-**  </ul>
+** </ul>
 **
-** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(),
-** or sqlite3_column_text16() first to force the result into the desired
-** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to
-** find the size of the result.  Do not mix call to sqlite3_column_text() or
-** sqlite3_column_blob() with calls to sqlite3_column_bytes16().  And do not
-** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes().
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
 **
 ** The pointers returned are valid until a type conversion occurs as
 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
 ** [sqlite3_finalize()] is called.  The memory space used to hold strings
-** and blobs is freed automatically.  Do <b>not</b> pass the pointers returned
-** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 
+** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
+** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
 ** [sqlite3_free()].
 **
 ** If a memory allocation error occurs during the evaluation of any
@@ -3706,60 +3622,9 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** pointer.  Subsequent calls to [sqlite3_errcode()] will return
 ** [SQLITE_NOMEM].
 **
-** INVARIANTS:
-**
-** {F13803} The [sqlite3_column_blob(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a blob and then returns a
-**          pointer to the converted value.
-**
-** {F13806} The [sqlite3_column_bytes(S,N)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_column_blob(S,N)] or
-**          [sqlite3_column_text(S,N)].
-**
-** {F13809} The [sqlite3_column_bytes16(S,N)] interface returns the
-**          number of bytes in the string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_column_text16(S,N)].
-**
-** {F13812} The [sqlite3_column_double(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a floating point value and
-**          returns a copy of that value.
-**
-** {F13815} The [sqlite3_column_int(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a 64-bit signed integer and
-**          returns the lower 32 bits of that integer.
-**
-** {F13818} The [sqlite3_column_int64(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a 64-bit signed integer and
-**          returns a copy of that integer.
-**
-** {F13821} The [sqlite3_column_text(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a zero-terminated UTF-8 
-**          string and returns a pointer to that string.
-**
-** {F13824} The [sqlite3_column_text16(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a zero-terminated 2-byte
-**          aligned UTF-16 native byte order
-**          string and returns a pointer to that string.
-**
-** {F13827} The [sqlite3_column_type(S,N)] interface returns
-**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
-**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
-**          the Nth column in the current row of the result set for
-**          [prepared statement] S.
-**
-** {F13830} The [sqlite3_column_value(S,N)] interface returns a
-**          pointer to an [unprotected sqlite3_value] object for the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S.
+** Requirements:
+** [H13803] [H13806] [H13809] [H13812] [H13815] [H13818] [H13821] [H13824]
+** [H13827] [H13830]
 */
 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
@@ -3773,186 +3638,135 @@ SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
 
 /*
-** CAPI3REF: Destroy A Prepared Statement Object {F13300}
+** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
 **
-** The sqlite3_finalize() function is called to delete a 
-** [prepared statement]. If the statement was
-** executed successfully, or not executed at all, then SQLITE_OK is returned.
-** If execution of the statement failed then an 
-** [error code] or [extended error code]
-** is returned. 
+** The sqlite3_finalize() function is called to delete a [prepared statement].
+** If the statement was executed successfully or not executed at all, then
+** SQLITE_OK is returned. If execution of the statement failed then an
+** [error code] or [extended error code] is returned.
 **
 ** This routine can be called at any point during the execution of the
-** [prepared statement].  If the virtual machine has not 
+** [prepared statement].  If the virtual machine has not
 ** completed execution when this routine is called, that is like
-** encountering an error or an interrupt.  (See [sqlite3_interrupt()].) 
-** Incomplete updates may be rolled back and transactions cancelled,  
-** depending on the circumstances, and the 
+** encountering an error or an [sqlite3_interrupt | interrupt].
+** Incomplete updates may be rolled back and transactions canceled,
+** depending on the circumstances, and the
 ** [error code] returned will be [SQLITE_ABORT].
 **
-** INVARIANTS:
-**
-** {F11302} The [sqlite3_finalize(S)] interface destroys the
-**          [prepared statement] S and releases all
-**          memory and file resources held by that object.
-**
-** {F11304} If the most recent call to [sqlite3_step(S)] for the
-**          [prepared statement] S returned an error,
-**          then [sqlite3_finalize(S)] returns that same error.
+** Requirements:
+** [H11302] [H11304]
 */
 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Reset A Prepared Statement Object {F13330}
+** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
 **
-** The sqlite3_reset() function is called to reset a 
-** [prepared statement] object.
-** back to its initial state, ready to be re-executed.
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
 ** Any SQL statement variables that had values bound to them using
 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
 ** Use [sqlite3_clear_bindings()] to reset the bindings.
 **
-** {F11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
 **          back to the beginning of its program.
 **
-** {F11334} If the most recent call to [sqlite3_step(S)] for 
+** {H11334} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
 **          or if [sqlite3_step(S)] has never before been called on S,
 **          then [sqlite3_reset(S)] returns [SQLITE_OK].
 **
-** {F11336} If the most recent call to [sqlite3_step(S)] for
+** {H11336} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S indicated an error, then
 **          [sqlite3_reset(S)] returns an appropriate [error code].
 **
-** {F11338} The [sqlite3_reset(S)] interface does not change the values
-**          of any [sqlite3_bind_blob|bindings] on [prepared statement] S.
+** {H11338} The [sqlite3_reset(S)] interface does not change the values
+**          of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
 */
 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Create Or Redefine SQL Functions {F16100}
-** KEYWORDS: {function creation routines} 
+** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
 **
-** These two functions (collectively known as
-** "function creation routines") are used to add SQL functions or aggregates
-** or to redefine the behavior of existing SQL functions or aggregates.  The
-** difference only between the two is that the second parameter, the
-** name of the (scalar) function or aggregate, is encoded in UTF-8 for
-** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
+** These two functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates.  The only difference between the
+** two is that the second parameter, the name of the (scalar) function or
+** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
+** for sqlite3_create_function16().
 **
 ** The first parameter is the [database connection] to which the SQL
-** function is to be added.  If a single
-** program uses more than one [database connection] internally, then SQL
-** functions must be added individually to each [database connection].
-**
-** The second parameter is the name of the SQL function to be created
-** or redefined.
-** The length of the name is limited to 255 bytes, exclusive of the 
-** zero-terminator.  Note that the name length limit is in bytes, not
-** characters.  Any attempt to create a function with a longer name
-** will result in an SQLITE_ERROR error.
+** function is to be added.  If a single program uses more than one database
+** connection internally, then SQL functions must be added individually to
+** each database connection.
 **
-** The third parameter is the number of arguments that the SQL function or
-** aggregate takes. If this parameter is negative, then the SQL function or
-** aggregate may take any number of arguments.
+** The second parameter is the name of the SQL function to be created or
+** redefined.  The length of the name is limited to 255 bytes, exclusive of
+** the zero-terminator.  Note that the name length limit is in bytes, not
+** characters.  Any attempt to create a function with a longer name
+** will result in [SQLITE_ERROR] being returned.
+**
+** The third parameter (nArg)
+** is the number of arguments that the SQL function or
+** aggregate takes. If this parameter is -1, then the SQL function or
+** aggregate may take any number of arguments between 0 and the limit
+** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
+** parameter is less than -1 or greater than 127 then the behavior is
+** undefined.
 **
-** The fourth parameter, eTextRep, specifies what 
+** The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
 ** its parameters.  Any SQL function implementation should be able to work
 ** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
-** more efficient with one encoding than another.  It is allowed to
+** more efficient with one encoding than another.  An application may
 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
 ** times with the same function but with different values of eTextRep.
 ** When multiple implementations of the same function are available, SQLite
 ** will pick the one that involves the least amount of data conversion.
-** If there is only a single implementation which does not care what
-** text encoding is used, then the fourth argument should be
-** [SQLITE_ANY].
+** If there is only a single implementation which does not care what text
+** encoding is used, then the fourth argument should be [SQLITE_ANY].
 **
-** The fifth parameter is an arbitrary pointer.  The implementation
-** of the function can gain access to this pointer using
-** [sqlite3_user_data()].
+** The fifth parameter is an arbitrary pointer.  The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].
 **
 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
-** pointers to C-language functions that implement the SQL
-** function or aggregate. A scalar SQL function requires an implementation of
-** the xFunc callback only, NULL pointers should be passed as the xStep
-** and xFinal parameters. An aggregate SQL function requires an implementation
-** of xStep and xFinal and NULL should be passed for xFunc. To delete an
-** existing SQL function or aggregate, pass NULL for all three function
-** callback.
+** pointers to C-language functions that implement the SQL function or
+** aggregate. A scalar SQL function requires an implementation of the xFunc
+** callback only, NULL pointers should be passed as the xStep and xFinal
+** parameters. An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL should be passed for xFunc. To delete an existing
+** SQL function or aggregate, pass NULL for all three function callbacks.
 **
 ** It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
-** arguments or differing perferred text encodings.  SQLite will use
-** the implementation most closely matches the way in which the
-** SQL function is used.
-**
-** INVARIANTS:
-**
-** {F16103} The [sqlite3_create_function16()] interface behaves exactly
-**          like [sqlite3_create_function()] in every way except that it
-**          interprets the zFunctionName argument as
-**          zero-terminated UTF-16 native byte order instead of as a
-**          zero-terminated UTF-8.
-**
-** {F16106} A successful invocation of
-**          the [sqlite3_create_function(D,X,N,E,...)] interface registers
-**          or replaces callback functions in [database connection] D
-**          used to implement the SQL function named X with N parameters
-**          and having a perferred text encoding of E.
-**
-** {F16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          replaces the P, F, S, and L values from any prior calls with
-**          the same D, X, N, and E values.
-**
-** {F16112} The [sqlite3_create_function(D,X,...)] interface fails with
-**          a return code of [SQLITE_ERROR] if the SQL function name X is
-**          longer than 255 bytes exclusive of the zero terminator.
-**
-** {F16118} Either F must be NULL and S and L are non-NULL or else F
-**          is non-NULL and S and L are NULL, otherwise
-**          [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
-**
-** {F16121} The [sqlite3_create_function(D,...)] interface fails with an
-**          error code of [SQLITE_BUSY] if there exist [prepared statements]
-**          associated with the [database connection] D.
-**
-** {F16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
-**          error code of [SQLITE_ERROR] if parameter N (specifying the number
-**          of arguments to the SQL function being registered) is less
-**          than -1 or greater than 127.
-**
-** {F16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
-**          named X when the number of arguments to the SQL function is
-**          exactly N.
-**
-** {F16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
-**          named X with any number of arguments.
-**
-** {F16133} When calls to [sqlite3_create_function(D,X,N,...)]
-**          specify multiple implementations of the same function X
-**          and when one implementation has N>=0 and the other has N=(-1)
-**          the implementation with a non-zero N is preferred.
-**
-** {F16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
-**          specify multiple implementations of the same function X with
-**          the same number of arguments N but with different
-**          encodings E, then the implementation where E matches the
-**          database encoding is preferred.
-**
-** {F16139} For an aggregate SQL function created using
-**          [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finializer
-**          function L will always be invoked exactly once if the
-**          step function S is called one or more times.
-**
-** {F16142} When SQLite invokes either the xFunc or xStep function of
-**          an application-defined SQL function or aggregate created
-**          by [sqlite3_create_function()] or [sqlite3_create_function16()],
-**          then the array of [sqlite3_value] objects passed as the
-**          third parameter are always [protected sqlite3_value] objects.
+** arguments or differing preferred text encodings.  SQLite will use
+** the implementation that most closely matches the way in which the
+** SQL function is used.  A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg.  A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.  
+** A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** Built-in functions may be overloaded by new application-defined functions.
+** The first application-defined function with a given name overrides all
+** built-in functions in the same [database connection] with the same name.
+** Subsequent application-defined functions of the same name only override 
+** prior application-defined functions that are an exact match for the
+** number of parameters and preferred encoding.
+**
+** An application-defined function is permitted to call other
+** SQLite interfaces.  However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
+**
+** Requirements:
+** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127]
+** [H16130] [H16133] [H16136] [H16139] [H16142]
 */
 SQLITE_API int sqlite3_create_function(
   sqlite3 *db,
@@ -3976,7 +3790,7 @@ SQLITE_API int sqlite3_create_function16(
 );
 
 /*
-** CAPI3REF: Text Encodings {F10267}
+** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
 **
 ** These constant define integer codes that represent the various
 ** text encodings supported by SQLite.
@@ -3989,23 +3803,26 @@ SQLITE_API int sqlite3_create_function16(
 #define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
 
 /*
-** CAPI3REF: Obsolete Functions
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
 **
-** These functions are all now obsolete.  In order to maintain
-** backwards compatibility with older code, we continue to support
-** these functions.  However, new development projects should avoid
+** These functions are [deprecated].  In order to maintain
+** backwards compatibility with older code, these functions continue 
+** to be supported.  However, new applications should avoid
 ** the use of these functions.  To help encourage people to avoid
-** using these functions, we are not going to tell you want they do.
+** using these functions, we are not going to tell you what they do.
 */
-SQLITE_API int sqlite3_aggregate_count(sqlite3_context*);
-SQLITE_API int sqlite3_expired(sqlite3_stmt*);
-SQLITE_API int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
-SQLITE_API int sqlite3_global_recover(void);
-SQLITE_API void sqlite3_thread_cleanup(void);
-SQLITE_API int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#endif
 
 /*
-** CAPI3REF: Obtaining SQL Function Parameter Values {F15100}
+** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
 **
 ** The C-language implementation of SQL functions and aggregates uses
 ** this set of interface routines to access the parameter values on
@@ -4023,95 +3840,35 @@ SQLITE_API int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlit
 ** Any attempt to use these routines on an [unprotected sqlite3_value]
 ** object results in undefined behavior.
 **
-** These routines work just like the corresponding 
-** [sqlite3_column_blob | sqlite3_column_* routines] except that 
-** these routines take a single [protected sqlite3_value] object pointer
-** instead of an [sqlite3_stmt*] pointer and an integer column number.
+** These routines work just like the corresponding [column access functions]
+** except that  these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
 **
-** The sqlite3_value_text16() interface extracts a UTF16 string
+** The sqlite3_value_text16() interface extracts a UTF-16 string
 ** in the native byte-order of the host machine.  The
 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
-** extract UTF16 strings as big-endian and little-endian respectively.
+** extract UTF-16 strings as big-endian and little-endian respectively.
 **
 ** The sqlite3_value_numeric_type() interface attempts to apply
 ** numeric affinity to the value.  This means that an attempt is
 ** made to convert the value to an integer or floating point.  If
 ** such a conversion is possible without loss of information (in other
-** words if the value is a string that looks like a number)
-** then the conversion is done.  Otherwise no conversion occurs.  The 
-** [SQLITE_INTEGER | datatype] after conversion is returned.
+** words, if the value is a string that looks like a number)
+** then the conversion is performed.  Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.
 **
-** Please pay particular attention to the fact that the pointer that
-** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
-** or [sqlite3_value_text16()].  
+** or [sqlite3_value_text16()].
 **
 ** These routines must be called from the same thread as
 ** the SQL function that supplied the [sqlite3_value*] parameters.
 **
-**
-** INVARIANTS:
-**
-** {F15103} The [sqlite3_value_blob(V)] interface converts the
-**          [protected sqlite3_value] object V into a blob and then returns a
-**          pointer to the converted value.
-**
-** {F15106} The [sqlite3_value_bytes(V)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_value_blob(V)] or
-**          [sqlite3_value_text(V)].
-**
-** {F15109} The [sqlite3_value_bytes16(V)] interface returns the
-**          number of bytes in the string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_value_text16(V)],
-**          [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
-**
-** {F15112} The [sqlite3_value_double(V)] interface converts the
-**          [protected sqlite3_value] object V into a floating point value and
-**          returns a copy of that value.
-**
-** {F15115} The [sqlite3_value_int(V)] interface converts the
-**          [protected sqlite3_value] object V into a 64-bit signed integer and
-**          returns the lower 32 bits of that integer.
-**
-** {F15118} The [sqlite3_value_int64(V)] interface converts the
-**          [protected sqlite3_value] object V into a 64-bit signed integer and
-**          returns a copy of that integer.
-**
-** {F15121} The [sqlite3_value_text(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated UTF-8 
-**          string and returns a pointer to that string.
-**
-** {F15124} The [sqlite3_value_text16(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 native byte order
-**          string and returns a pointer to that string.
-**
-** {F15127} The [sqlite3_value_text16be(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 big-endian
-**          string and returns a pointer to that string.
-**
-** {F15130} The [sqlite3_value_text16le(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 little-endian
-**          string and returns a pointer to that string.
-**
-** {F15133} The [sqlite3_value_type(V)] interface returns
-**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
-**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
-**          the [sqlite3_value] object V.
-**
-** {F15136} The [sqlite3_value_numeric_type(V)] interface converts
-**          the [protected sqlite3_value] object V into either an integer or
-**          a floating point value if it can do so without loss of
-**          information, and returns one of [SQLITE_NULL],
-**          [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
-**          [SQLITE_BLOB] as appropriate for
-**          the [protected sqlite3_value] object V after the conversion attempt.
+** Requirements:
+** [H15103] [H15106] [H15109] [H15112] [H15115] [H15118] [H15121] [H15124]
+** [H15127] [H15130] [H15133] [H15136]
 */
 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
 SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
@@ -4127,175 +3884,120 @@ SQLITE_API int sqlite3_value_type(sqlite3_value*);
 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
 
 /*
-** CAPI3REF: Obtain Aggregate Function Context {F16210}
+** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
 **
 ** The implementation of aggregate SQL functions use this routine to allocate
-** a structure for storing their state.  
-** The first time the sqlite3_aggregate_context() routine is
-** is called for a particular aggregate, SQLite allocates nBytes of memory
-** zeros that memory, and returns a pointer to it.
-** On second and subsequent calls to sqlite3_aggregate_context()
-** for the same aggregate function index, the same buffer is returned.
-** The implementation
-** of the aggregate can use the returned buffer to accumulate data.
+** a structure for storing their state.
+**
+** The first time the sqlite3_aggregate_context() routine is called for a
+** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
+** memory, and returns a pointer to it. On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function index,
+** the same buffer is returned. The implementation of the aggregate can use
+** the returned buffer to accumulate data.
 **
 ** SQLite automatically frees the allocated buffer when the aggregate
 ** query concludes.
 **
-** The first parameter should be a copy of the 
-** [sqlite3_context | SQL function context] that is the first
-** parameter to the callback routine that implements the aggregate
-** function.
+** The first parameter should be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the callback routine that implements the aggregate function.
 **
 ** This routine must be called from the same thread in which
 ** the aggregate SQL function is running.
 **
-** INVARIANTS:
-**
-** {F16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
-**          a particular instance of an aggregate function (for a particular
-**          context C) causes SQLite to allocation N bytes of memory,
-**          zero that memory, and return a pointer to the allocationed
-**          memory.
-**
-** {F16213} If a memory allocation error occurs during
-**          [sqlite3_aggregate_context(C,N)] then the function returns 0.
-**
-** {F16215} Second and subsequent invocations of
-**          [sqlite3_aggregate_context(C,N)] for the same context pointer C
-**          ignore the N parameter and return a pointer to the same
-**          block of memory returned by the first invocation.
-**
-** {F16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
-**          automatically freed on the next call to [sqlite3_reset()]
-**          or [sqlite3_finalize()] for the [prepared statement] containing
-**          the aggregate function associated with context C.
+** Requirements:
+** [H16211] [H16213] [H16215] [H16217]
 */
 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
 
 /*
-** CAPI3REF: User Data For Functions {F16240}
+** CAPI3REF: User Data For Functions {H16240} <S20200>
 **
 ** The sqlite3_user_data() interface returns a copy of
 ** the pointer that was the pUserData parameter (the 5th parameter)
-** of the the [sqlite3_create_function()]
+** of the [sqlite3_create_function()]
 ** and [sqlite3_create_function16()] routines that originally
 ** registered the application defined function. {END}
 **
 ** This routine must be called from the same thread in which
 ** the application-defined function is running.
 **
-** INVARIANTS:
-**
-** {F16243} The [sqlite3_user_data(C)] interface returns a copy of the
-**          P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
-**          registered the SQL function associated with 
-**          [sqlite3_context] C.
+** Requirements:
+** [H16243]
 */
 SQLITE_API void *sqlite3_user_data(sqlite3_context*);
 
 /*
-** CAPI3REF: Database Connection For Functions {F16250}
+** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
 **
 ** The sqlite3_context_db_handle() interface returns a copy of
 ** the pointer to the [database connection] (the 1st parameter)
-** of the the [sqlite3_create_function()]
+** of the [sqlite3_create_function()]
 ** and [sqlite3_create_function16()] routines that originally
 ** registered the application defined function.
 **
-** INVARIANTS:
-**
-** {F16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
-**          D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
-**          registered the SQL function associated with 
-**          [sqlite3_context] C.
+** Requirements:
+** [H16253]
 */
 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
 
 /*
-** CAPI3REF: Function Auxiliary Data {F16270}
+** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
 **
 ** The following two functions may be used by scalar SQL functions to
-** associate meta-data with argument values. If the same value is passed to
+** associate metadata with argument values. If the same value is passed to
 ** multiple invocations of the same SQL function during query execution, under
-** some circumstances the associated meta-data may be preserved. This may
+** some circumstances the associated metadata may be preserved. This may
 ** be used, for example, to add a regular-expression matching scalar
 ** function. The compiled version of the regular expression is stored as
-** meta-data associated with the SQL value passed as the regular expression
+** metadata associated with the SQL value passed as the regular expression
 ** pattern.  The compiled regular expression can be reused on multiple
 ** invocations of the same function so that the original pattern string
 ** does not need to be recompiled on each invocation.
 **
-** The sqlite3_get_auxdata() interface returns a pointer to the meta-data
+** The sqlite3_get_auxdata() interface returns a pointer to the metadata
 ** associated by the sqlite3_set_auxdata() function with the Nth argument
-** value to the application-defined function.
-** If no meta-data has been ever been set for the Nth
-** argument of the function, or if the cooresponding function parameter
-** has changed since the meta-data was set, then sqlite3_get_auxdata()
-** returns a NULL pointer.
-**
-** The sqlite3_set_auxdata() interface saves the meta-data
-** pointed to by its 3rd parameter as the meta-data for the N-th
+** value to the application-defined function. If no metadata has been ever
+** been set for the Nth argument of the function, or if the corresponding
+** function parameter has changed since the meta-data was set,
+** then sqlite3_get_auxdata() returns a NULL pointer.
+**
+** The sqlite3_set_auxdata() interface saves the metadata
+** pointed to by its 3rd parameter as the metadata for the N-th
 ** argument of the application-defined function.  Subsequent
 ** calls to sqlite3_get_auxdata() might return this data, if it has
-** not been destroyed. 
-** If it is not NULL, SQLite will invoke the destructor 
+** not been destroyed.
+** If it is not NULL, SQLite will invoke the destructor
 ** function given by the 4th parameter to sqlite3_set_auxdata() on
-** the meta-data when the corresponding function parameter changes
+** the metadata when the corresponding function parameter changes
 ** or when the SQL statement completes, whichever comes first.
 **
-** SQLite is free to call the destructor and drop meta-data on
-** any parameter of any function at any time.  The only guarantee
-** is that the destructor will be called before the metadata is
-** dropped.
+** SQLite is free to call the destructor and drop metadata on any
+** parameter of any function at any time.  The only guarantee is that
+** the destructor will be called before the metadata is dropped.
 **
-** In practice, meta-data is preserved between function calls for
+** In practice, metadata is preserved between function calls for
 ** expressions that are constant at compile time. This includes literal
 ** values and SQL variables.
 **
 ** These routines must be called from the same thread in which
 ** the SQL function is running.
 **
-** INVARIANTS:
-**
-** {F16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
-**          to metadata associated with the Nth parameter of the SQL function
-**          whose context is C, or NULL if there is no metadata associated
-**          with that parameter.
-**
-** {F16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
-**          pointer P to the Nth parameter of the SQL function with context
-**          C.
-**
-** {F16276} SQLite will invoke the destructor D with a single argument
-**          which is the metadata pointer P following a call to
-**          [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
-**          the metadata.
-**
-** {F16277} SQLite ceases to hold metadata for an SQL function parameter
-**          when the value of that parameter changes.
-**
-** {F16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
-**          is called for any prior metadata associated with the same function
-**          context C and parameter N.
-**
-** {F16279} SQLite will call destructors for any metadata it is holding
-**          in a particular [prepared statement] S when either
-**          [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
+** Requirements:
+** [H16272] [H16274] [H16276] [H16277] [H16278] [H16279]
 */
 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
 
 
 /*
-** CAPI3REF: Constants Defining Special Destructor Behavior {F10280}
+** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
 **
-** These are special value for the destructor that is passed in as the
+** These are special values for the destructor that is passed in as the
 ** final argument to routines like [sqlite3_result_blob()].  If the destructor
 ** argument is SQLITE_STATIC, it means that the content pointer is constant
-** and will never change.  It does not need to be destroyed.  The 
+** and will never change.  It does not need to be destroyed.  The
 ** SQLITE_TRANSIENT value means that the content will likely change in
 ** the near future and that SQLite should make its own private copy of
 ** the content before returning.
@@ -4308,30 +4010,28 @@ typedef void (*sqlite3_destructor_type)(void*);
 #define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
 
 /*
-** CAPI3REF: Setting The Result Of An SQL Function {F16400}
+** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
 **
 ** These routines are used by the xFunc or xFinal callbacks that
 ** implement SQL functions and aggregates.  See
 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
 ** for additional information.
 **
-** These functions work very much like the 
-** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used
-** to bind values to host parameters in prepared statements.
-** Refer to the
-** [sqlite3_bind_blob | sqlite3_bind_* documentation] for
-** additional information.
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
 **
 ** The sqlite3_result_blob() interface sets the result from
-** an application defined function to be the BLOB whose content is pointed
+** an application-defined function to be the BLOB whose content is pointed
 ** to by the second parameter and which is N bytes long where N is the
-** third parameter. 
-** The sqlite3_result_zeroblob() inerfaces set the result of
-** the application defined function to be a BLOB containing all zero
+** third parameter.
+**
+** The sqlite3_result_zeroblob() interfaces set the result of
+** the application-defined function to be a BLOB containing all zero
 ** bytes and N bytes in size, where N is the value of the 2nd parameter.
 **
 ** The sqlite3_result_double() interface sets the result from
-** an application defined function to be a floating point value specified
+** an application-defined function to be a floating point value specified
 ** by its 2nd argument.
 **
 ** The sqlite3_result_error() and sqlite3_result_error16() functions
@@ -4339,8 +4039,8 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite uses the string pointed to by the
 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
 ** as the text of an error message.  SQLite interprets the error
-** message string from sqlite3_result_error() as UTF8. SQLite
-** interprets the string from sqlite3_result_error16() as UTF16 in native
+** message string from sqlite3_result_error() as UTF-8. SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
 ** byte order.  If the third parameter to sqlite3_result_error()
 ** or sqlite3_result_error16() is negative then SQLite takes as the error
 ** message all text up through the first zero character.
@@ -4348,7 +4048,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** sqlite3_result_error16() is non-negative then SQLite takes that many
 ** bytes (not characters) from the 2nd parameter as the error message.
 ** The sqlite3_result_error() and sqlite3_result_error16()
-** routines make a copy private copy of the error message text before
+** routines make a private copy of the error message text before
 ** they return.  Hence, the calling function can deallocate or
 ** modify the text after they return without harm.
 ** The sqlite3_result_error_code() function changes the error code
@@ -4356,11 +4056,11 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the error code is SQLITE_ERROR.  A subsequent call to sqlite3_result_error()
 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
 **
-** The sqlite3_result_toobig() interface causes SQLite
-** to throw an error indicating that a string or BLOB is to long
-** to represent.  The sqlite3_result_nomem() interface
-** causes SQLite to throw an exception indicating that the a
-** memory allocation failed.
+** The sqlite3_result_toobig() interface causes SQLite to throw an error
+** indicating that a string or BLOB is to long to represent.
+**
+** The sqlite3_result_nomem() interface causes SQLite to throw an error
+** indicating that a memory allocation failed.
 **
 ** The sqlite3_result_int() interface sets the return value
 ** of the application-defined function to be the 32-bit signed integer
@@ -4372,7 +4072,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** The sqlite3_result_null() interface sets the return value
 ** of the application-defined function to be NULL.
 **
-** The sqlite3_result_text(), sqlite3_result_text16(), 
+** The sqlite3_result_text(), sqlite3_result_text16(),
 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
 ** set the return value of the application-defined function to be
 ** a text string which is represented as UTF-8, UTF-16 native byte order,
@@ -4380,7 +4080,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite takes the text result from the application from
 ** the 2nd parameter of the sqlite3_result_text* interfaces.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
-** is negative, then SQLite takes result text from the 2nd parameter 
+** is negative, then SQLite takes result text from the 2nd parameter
 ** through the first zero character.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
 ** is non-negative, then as many bytes (not characters) of the text
@@ -4388,13 +4088,13 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** function result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
-** function as the destructor on the text or blob result when it has
-** finished using that result.
-** If the 4th parameter to the sqlite3_result_text* interfaces
-** or sqlite3_result_blob is the special constant SQLITE_STATIC, then
-** SQLite assumes that the text or blob result is constant space and
-** does not copy the space or call a destructor when it has
+** function as the destructor on the text or BLOB result when it has
 ** finished using that result.
+** If the 4th parameter to the sqlite3_result_text* interfaces or to
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the content of the parameter nor call a destructor on the content
+** when it has finished using that result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
 ** then SQLite makes a copy of the result into space obtained from
@@ -4404,111 +4104,20 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the application-defined function to be a copy the
 ** [unprotected sqlite3_value] object specified by the 2nd parameter.  The
 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
-** so that [sqlite3_value] specified in the parameter may change or
+** so that the [sqlite3_value] specified in the parameter may change or
 ** be deallocated after sqlite3_result_value() returns without harm.
 ** A [protected sqlite3_value] object may always be used where an
 ** [unprotected sqlite3_value] object is required, so either
 ** kind of [sqlite3_value] object can be used with this interface.
 **
-** If these routines are called from within the different thread 
-** than the one containing the application-defined function that recieved
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
 ** the [sqlite3_context] pointer, the results are undefined.
 **
-** INVARIANTS:
-**
-** {F16403} The default return value from any SQL function is NULL.
-**
-** {F16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
-**          return value of function C to be a blob that is N bytes
-**          in length and with content pointed to by V.
-**
-** {F16409} The [sqlite3_result_double(C,V)] interface changes the
-**          return value of function C to be the floating point value V.
-**
-** {F16412} The [sqlite3_result_error(C,V,N)] interface changes the return
-**          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF8 error message copied from V up to the
-**          first zero byte or until N bytes are read if N is positive.
-**
-** {F16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
-**          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF16 native byte order error message
-**          copied from V up to the first zero terminator or until N bytes
-**          are read if N is positive.
-**
-** {F16418} The [sqlite3_result_error_toobig(C)] interface changes the return
-**          value of the function C to be an exception with error code
-**          [SQLITE_TOOBIG] and an appropriate error message.
-**
-** {F16421} The [sqlite3_result_error_nomem(C)] interface changes the return
-**          value of the function C to be an exception with error code
-**          [SQLITE_NOMEM] and an appropriate error message.
-**
-** {F16424} The [sqlite3_result_error_code(C,E)] interface changes the return
-**          value of the function C to be an exception with error code E.
-**          The error message text is unchanged.
-**
-** {F16427} The [sqlite3_result_int(C,V)] interface changes the
-**          return value of function C to be the 32-bit integer value V.
-**
-** {F16430} The [sqlite3_result_int64(C,V)] interface changes the
-**          return value of function C to be the 64-bit integer value V.
-**
-** {F16433} The [sqlite3_result_null(C)] interface changes the
-**          return value of function C to be NULL.
-**
-** {F16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF8 string
-**          V up to the first zero if N is negative
-**          or the first N bytes of V if N is non-negative.
-**
-** {F16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 native byte order
-**          string V up to the first zero if N is
-**          negative or the first N bytes of V if N is non-negative.
-**
-** {F16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 big-endian
-**          string V up to the first zero if N is
-**          is negative or the first N bytes or V if N is non-negative.
-**
-** {F16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 little-endian
-**          string V up to the first zero if N is
-**          negative or the first N bytes of V if N is non-negative.
-**
-** {F16448} The [sqlite3_result_value(C,V)] interface changes the
-**          return value of function C to be [unprotected sqlite3_value]
-**          object V.
-**
-** {F16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
-**          return value of function C to be an N-byte blob of all zeros.
-**
-** {F16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
-**          interfaces make a copy of their error message strings before
-**          returning.
-**
-** {F16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
-**          then no destructor is ever called on the pointer V and SQLite
-**          assumes that V is immutable.
-**
-** {F16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is the constant
-**          [SQLITE_TRANSIENT] then the interfaces makes a copy of the
-**          content of V and retains the copy.
-**
-** {F16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is some value other than
-**          the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then 
-**          SQLite will invoke the destructor D with V as its only argument
-**          when it has finished with the V value.
+** Requirements:
+** [H16403] [H16406] [H16409] [H16412] [H16415] [H16418] [H16421] [H16424]
+** [H16427] [H16430] [H16433] [H16436] [H16439] [H16442] [H16445] [H16448]
+** [H16451] [H16454] [H16457] [H16460] [H16463]
 */
 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
 SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
@@ -4528,10 +4137,10 @@ SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
 
 /*
-** CAPI3REF: Define New Collating Sequences {F16600}
+** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
 **
 ** These functions are used to add new collation sequences to the
-** [sqlite3*] handle specified as the first argument. 
+** [database connection] specified as the first argument.
 **
 ** The name of the new collation sequence is specified as a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
@@ -4539,86 +4148,43 @@ SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
 ** the name is passed as the second function argument.
 **
 ** The third argument may be one of the constants [SQLITE_UTF8],
-** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
+** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
 ** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian or UTF-16 big-endian respectively. The
-** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
+** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
+** third argument might also be [SQLITE_UTF16] to indicate that the routine
+** expects pointers to be UTF-16 strings in the native byte order, or the
+** argument can be [SQLITE_UTF16_ALIGNED] if the
 ** the routine expects pointers to 16-bit word aligned strings
-** of UTF16 in the native byte order of the host computer.
+** of UTF-16 in the native byte order.
 **
 ** A pointer to the user supplied routine must be passed as the fifth
 ** argument.  If it is NULL, this is the same as deleting the collation
 ** sequence (so that SQLite cannot call it anymore).
-** Each time the application
-** supplied function is invoked, it is passed a copy of the void* passed as
-** the fourth argument to sqlite3_create_collation() or
-** sqlite3_create_collation16() as its first parameter.
+** Each time the application supplied function is invoked, it is passed
+** as its first parameter a copy of the void* passed as the fourth argument
+** to sqlite3_create_collation() or sqlite3_create_collation16().
 **
 ** The remaining arguments to the application-supplied routine are two strings,
 ** each represented by a (length, data) pair and encoded in the encoding
 ** that was passed as the third argument when the collation sequence was
-** registered. {END} The application defined collation routine should
-** return negative, zero or positive if
-** the first string is less than, equal to, or greater than the second
-** string. i.e. (STRING1 - STRING2).
+** registered. {END}  The application defined collation routine should
+** return negative, zero or positive if the first string is less than,
+** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
 **
 ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** excapt that it takes an extra argument which is a destructor for
+** except that it takes an extra argument which is a destructor for
 ** the collation.  The destructor is called when the collation is
 ** destroyed and is passed a copy of the fourth parameter void* pointer
 ** of the sqlite3_create_collation_v2().
-** Collations are destroyed when
-** they are overridden by later calls to the collation creation functions
-** or when the [sqlite3*] database handle is closed using [sqlite3_close()].
-**
-** INVARIANTS:
-**
-** {F16603} A successful call to the
-**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
-**          registers function F as the comparison function used to
-**          implement collation X on [database connection] B for
-**          databases having encoding E.
-**
-** {F16604} SQLite understands the X parameter to
-**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
-**          UTF-8 string in which case is ignored for ASCII characters and
-**          is significant for non-ASCII characters.
-**
-** {F16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          with the same values for B, X, and E, override prior values
-**          of P, F, and D.
-**
-** {F16609} The destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          is not NULL then it is called with argument P when the
-**          collating function is dropped by SQLite.
-**
-** {F16612} A collating function is dropped when it is overloaded.
-**
-** {F16615} A collating function is dropped when the database connection
-**          is closed using [sqlite3_close()].
+** Collations are destroyed when they are overridden by later calls to the
+** collation creation functions or when the [database connection] is closed
+** using [sqlite3_close()].
 **
-** {F16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          is passed through as the first parameter to the comparison
-**          function F for all subsequent invocations of F.
+** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
 **
-** {F16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
-**          the same as a call to [sqlite3_create_collation_v2()] with
-**          the same parameters and a NULL destructor.
-**
-** {F16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
-**          SQLite uses the comparison function F for all text comparison
-**          operations on [database connection] B on text values that
-**          use the collating sequence name X.
-**
-** {F16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
-**          as [sqlite3_create_collation(B,X,E,P,F)] except that the
-**          collation name X is understood as UTF-16 in native byte order
-**          instead of UTF-8.
-**
-** {F16630} When multiple comparison functions are available for the same
-**          collating sequence, SQLite chooses the one whose text encoding
-**          requires the least amount of conversion from the default
-**          text encoding of the database.
+** Requirements:
+** [H16603] [H16604] [H16606] [H16609] [H16612] [H16615] [H16618] [H16621]
+** [H16624] [H16627] [H16630]
 */
 SQLITE_API int sqlite3_create_collation(
   sqlite3*, 
@@ -4637,59 +4203,40 @@ SQLITE_API int sqlite3_create_collation_v2(
 );
 SQLITE_API int sqlite3_create_collation16(
   sqlite3*, 
-  const char *zName, 
+  const void *zName,
   int eTextRep, 
   void*,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
 /*
-** CAPI3REF: Collation Needed Callbacks {F16700}
+** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
 **
 ** To avoid having to register all collation sequences before a database
 ** can be used, a single callback function may be registered with the
-** database handle to be called whenever an undefined collation sequence is
-** required.
+** [database connection] to be called whenever an undefined collation
+** sequence is required.
 **
 ** If the function is registered using the sqlite3_collation_needed() API,
 ** then it is passed the names of undefined collation sequences as strings
-** encoded in UTF-8. {F16703} If sqlite3_collation_needed16() is used, the names
-** are passed as UTF-16 in machine native byte order. A call to either
-** function replaces any existing callback.
+** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** A call to either function replaces any existing callback.
 **
 ** When the callback is invoked, the first argument passed is a copy
 ** of the second argument to sqlite3_collation_needed() or
 ** sqlite3_collation_needed16().  The second argument is the database
-** handle.  The third argument is one of [SQLITE_UTF8],
-** [SQLITE_UTF16BE], or [SQLITE_UTF16LE], indicating the most
-** desirable form of the collation sequence function required.
-** The fourth parameter is the name of the
+** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required.  The fourth parameter is the name of the
 ** required collation sequence.
 **
 ** The callback function should register the desired collation using
 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
 ** [sqlite3_create_collation_v2()].
 **
-** INVARIANTS:
-**
-** {F16702} A successful call to [sqlite3_collation_needed(D,P,F)]
-**          or [sqlite3_collation_needed16(D,P,F)] causes
-**          the [database connection] D to invoke callback F with first
-**          parameter P whenever it needs a comparison function for a
-**          collating sequence that it does not know about.
-**
-** {F16704} Each successful call to [sqlite3_collation_needed()] or
-**          [sqlite3_collation_needed16()] overrides the callback registered
-**          on the same [database connection] by prior calls to either
-**          interface.
-**
-** {F16706} The name of the requested collating function passed in the
-**          4th parameter to the callback is in UTF-8 if the callback
-**          was registered using [sqlite3_collation_needed()] and
-**          is in UTF-16 native byte order if the callback was
-**          registered using [sqlite3_collation_needed16()].
-**
-** 
+** Requirements:
+** [H16702] [H16704] [H16706]
 */
 SQLITE_API int sqlite3_collation_needed(
   sqlite3*, 
@@ -4728,128 +4275,143 @@ SQLITE_API int sqlite3_rekey(
 );
 
 /*
-** CAPI3REF:  Suspend Execution For A Short Time {F10530}
+** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
 **
-** The sqlite3_sleep() function
-** causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** If the operating system does not support sleep requests with 
-** millisecond time resolution, then the time will be rounded up to 
-** the nearest second. The number of milliseconds of sleep actually 
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** SQLite implements this interface by calling the xSleep()
 ** method of the default [sqlite3_vfs] object.
 **
-** INVARIANTS:
-**
-** {F10533} The [sqlite3_sleep(M)] interface invokes the xSleep
-**          method of the default [sqlite3_vfs|VFS] in order to
-**          suspend execution of the current thread for at least
-**          M milliseconds.
-**
-** {F10536} The [sqlite3_sleep(M)] interface returns the number of
-**          milliseconds of sleep actually requested of the operating
-**          system, which might be larger than the parameter M.
+** Requirements: [H10533] [H10536]
 */
 SQLITE_API int sqlite3_sleep(int);
 
 /*
-** CAPI3REF:  Name Of The Folder Holding Temporary Files {F10310}
+** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
 **
 ** If this global variable is made to point to a string which is
-** the name of a folder (a.ka. directory), then all temporary files
+** the name of a folder (a.k.a. directory), then all temporary files
 ** created by SQLite will be placed in that directory.  If this variable
-** is NULL pointer, then SQLite does a search for an appropriate temporary
-** file directory.
-**
-** It is not safe to modify this variable once a database connection
-** has been opened.  It is intended that this variable be set once
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time.  It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
 ** as part of process initialization and before any SQLite interface
-** routines have been call and remain unchanged thereafter.
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** The [temp_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc].  Furthermore,
+** the [temp_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from 
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [temp_store_directory pragma] should be avoided.
 */
 SQLITE_API char *sqlite3_temp_directory;
 
 /*
-** CAPI3REF:  Test To See If The Database Is In Auto-Commit Mode {F12930}
+** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
+** KEYWORDS: {autocommit mode}
 **
-** The sqlite3_get_autocommit() interfaces returns non-zero or
+** The sqlite3_get_autocommit() interface returns non-zero or
 ** zero if the given database connection is or is not in autocommit mode,
-** respectively.   Autocommit mode is on
-** by default.  Autocommit mode is disabled by a [BEGIN] statement.
-** Autocommit mode is reenabled by a [COMMIT] or [ROLLBACK].
+** respectively.  Autocommit mode is on by default.
+** Autocommit mode is disabled by a [BEGIN] statement.
+** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
 **
 ** If certain kinds of errors occur on a statement within a multi-statement
-** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR], 
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
 ** transaction might be rolled back automatically.  The only way to
-** find out if SQLite automatically rolled back the transaction after
+** find out whether SQLite automatically rolled back the transaction after
 ** an error is to use this function.
 **
-** INVARIANTS:
-**
-** {F12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
-**          zero if the [database connection] D is or is not in autocommit
-**          mode, respectively.
-**
-** {F12932} Autocommit mode is on by default.
-**
-** {F12933} Autocommit mode is disabled by a successful [BEGIN] statement.
-**
-** {F12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
-**          statement.
-** 
+** If another thread changes the autocommit status of the database
+** connection while this routine is running, then the return value
+** is undefined.
 **
-** LIMITATIONS:
-***
-** {U12936} If another thread changes the autocommit status of the database
-**          connection while this routine is running, then the return value
-**          is undefined.
+** Requirements: [H12931] [H12932] [H12933] [H12934]
 */
 SQLITE_API int sqlite3_get_autocommit(sqlite3*);
 
 /*
-** CAPI3REF:  Find The Database Handle Of A Prepared Statement {F13120}
-**
-** The sqlite3_db_handle interface
-** returns the [sqlite3*] database handle to which a
-** [prepared statement] belongs.
-** The database handle returned by sqlite3_db_handle
-** is the same database handle that was
-** the first argument to the [sqlite3_prepare_v2()] or its variants
-** that was used to create the statement in the first place.
+** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
 **
-** INVARIANTS:
+** The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs.  The [database connection]
+** returned by sqlite3_db_handle is the same [database connection] that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
 **
-** {F13123} The [sqlite3_db_handle(S)] interface returns a pointer
-**          to the [database connection] associated with
-**          [prepared statement] S.
+** Requirements: [H13123]
 */
 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 
+/*
+** CAPI3REF: Find the next prepared statement {H13140} <S60600>
+**
+** This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb.  If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb.  If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
+**
+** The [database connection] pointer D in a call to
+** [sqlite3_next_stmt(D,S)] must refer to an open database
+** connection and in particular must not be a NULL pointer.
+**
+** Requirements: [H13143] [H13146] [H13149] [H13152]
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Commit And Rollback Notification Callbacks {F12950}
+** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
 **
 ** The sqlite3_commit_hook() interface registers a callback
-** function to be invoked whenever a transaction is committed.
+** function to be invoked whenever a transaction is [COMMIT | committed].
 ** Any callback set by a previous call to sqlite3_commit_hook()
 ** for the same database connection is overridden.
 ** The sqlite3_rollback_hook() interface registers a callback
-** function to be invoked whenever a transaction is committed.
+** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
 ** Any callback set by a previous call to sqlite3_commit_hook()
 ** for the same database connection is overridden.
-** The pArg argument is passed through
-** to the callback.  If the callback on a commit hook function 
-** returns non-zero, then the commit is converted into a rollback.
+** The pArg argument is passed through to the callback.
+** If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
 **
 ** If another function was previously registered, its
 ** pArg value is returned.  Otherwise NULL is returned.
 **
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
 ** Registering a NULL function disables the callback.
 **
-** For the purposes of this API, a transaction is said to have been 
+** When the commit hook callback routine returns zero, the [COMMIT]
+** operation is allowed to continue normally.  If the commit hook
+** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
+** The rollback hook is invoked on a rollback that results from a commit
+** hook returning non-zero, just as it would be with any other rollback.
+**
+** For the purposes of this API, a transaction is said to have been
 ** rolled back if an explicit "ROLLBACK" statement is executed, or
 ** an error or constraint causes an implicit rollback to occur.
 ** The rollback callback is not invoked if a transaction is
@@ -4858,108 +4420,61 @@ SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 ** rolled back because a commit callback returned non-zero.
 ** <todo> Check on this </todo>
 **
-** These are experimental interfaces and are subject to change.
-**
-** INVARIANTS:
-**
-** {F12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
-**          callback function F to be invoked with argument P whenever
-**          a transaction commits on [database connection] D.
-**
-** {F12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
-**
-** {F12953} Each call to [sqlite3_commit_hook()] overwrites the callback
-**          registered by prior calls.
-**
-** {F12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
-**          then the commit hook callback is cancelled and no callback
-**          is invoked when a transaction commits.
-**
-** {F12955} If the commit callback returns non-zero then the commit is
-**          converted into a rollback.
-**
-** {F12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
-**          callback function F to be invoked with argument P whenever
-**          a transaction rolls back on [database connection] D.
+** See also the [sqlite3_update_hook()] interface.
 **
-** {F12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
-**
-** {F12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
-**          registered by prior calls.
-**
-** {F12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
-**          then the rollback hook callback is cancelled and no callback
-**          is invoked when a transaction rolls back.
+** Requirements:
+** [H12951] [H12952] [H12953] [H12954] [H12955]
+** [H12961] [H12962] [H12963] [H12964]
 */
 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
 
 /*
-** CAPI3REF: Data Change Notification Callbacks {F12970}
-**
-** The sqlite3_update_hook() interface
-** registers a callback function with the database connection identified by the 
-** first argument to be invoked whenever a row is updated, inserted or deleted.
-** Any callback set by a previous call to this function for the same 
-** database connection is overridden.
-**
-** The second argument is a pointer to the function to invoke when a 
-** row is updated, inserted or deleted. 
-** The first argument to the callback is
-** a copy of the third argument to sqlite3_update_hook().
-** The second callback 
-** argument is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
-** depending on the operation that caused the callback to be invoked.
-** The third and 
-** fourth arguments to the callback contain pointers to the database and 
-** table name containing the affected row.
-** The final callback parameter is 
-** the rowid of the row.
-** In the case of an update, this is the rowid after 
-** the update takes place.
-**
-** The update hook is not invoked when internal system tables are
-** modified (i.e. sqlite_master and sqlite_sequence).
+** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
 **
-** If another function was previously registered, its pArg value
-** is returned.  Otherwise NULL is returned.
-**
-** INVARIANTS:
+** The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted.
+** Any callback set by a previous call to this function
+** for the same database connection is overridden.
 **
-** {F12971} The [sqlite3_update_hook(D,F,P)] interface causes callback
-**          function F to be invoked with first parameter P whenever
-**          a table row is modified, inserted, or deleted on
-**          [database connection] D.
+** The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted.
+** The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** The final callback parameter is the [rowid] of the row.
+** In the case of an update, this is the [rowid] after the update takes place.
 **
-** {F12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
-**          of P for the previous call on the same [database connection] D,
-**          or NULL for the first call.
+** The update hook is not invoked when internal system tables are
+** modified (i.e. sqlite_master and sqlite_sequence).
 **
-** {F12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
-**          is NULL then the no update callbacks are made.
+** In the current implementation, the update hook
+** is not invoked when duplication rows are deleted because of an
+** [ON CONFLICT | ON CONFLICT REPLACE] clause.  Nor is the update hook
+** invoked when rows are deleted using the [truncate optimization].
+** The exceptions defined in this paragraph might change in a future
+** release of SQLite.
 **
-** {F12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
-**          to the same interface on the same [database connection] D.
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12979} The update hook callback is not invoked when internal system
-**          tables such as sqlite_master and sqlite_sequence are modified.
+** If another function was previously registered, its pArg value
+** is returned.  Otherwise NULL is returned.
 **
-** {F12981} The second parameter to the update callback 
-**          is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
-**          depending on the operation that caused the callback to be invoked.
+** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
+** interfaces.
 **
-** {F12983} The third and fourth arguments to the callback contain pointers
-**          to zero-terminated UTF-8 strings which are the names of the
-**          database and table that is being updated.
-
-** {F12985} The final callback parameter is the rowid of the row after
-**          the change occurs.
+** Requirements:
+** [H12971] [H12973] [H12975] [H12977] [H12979] [H12981] [H12983] [H12986]
 */
 SQLITE_API void *sqlite3_update_hook(
   sqlite3*, 
@@ -4968,96 +4483,74 @@ SQLITE_API void *sqlite3_update_hook(
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Shared Pager Cache {F10330}
+** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
+** KEYWORDS: {shared cache}
 **
 ** This routine enables or disables the sharing of the database cache
-** and schema data structures between connections to the same database.
-** Sharing is enabled if the argument is true and disabled if the argument
-** is false.
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.
 **
-** Cache sharing is enabled and disabled
-** for an entire process. {END} This is a change as of SQLite version 3.5.0.
-** In prior versions of SQLite, sharing was
-** enabled or disabled for each thread separately.
+** Cache sharing is enabled and disabled for an entire process.
+** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
 **
 ** The cache sharing mode set by this interface effects all subsequent
 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
 ** Existing database connections continue use the sharing mode
 ** that was in effect at the time they were opened.
 **
-** Virtual tables cannot be used with a shared cache.   When shared
+** Virtual tables cannot be used with a shared cache.  When shared
 ** cache is enabled, the [sqlite3_create_module()] API used to register
 ** virtual tables will always return an error.
 **
-** This routine returns [SQLITE_OK] if shared cache was
-** enabled or disabled successfully.  An [error code]
-** is returned otherwise.
+** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully.  An [error code] is returned otherwise.
 **
 ** Shared cache is disabled by default. But this might change in
 ** future releases of SQLite.  Applications that care about shared
 ** cache setting should set it explicitly.
 **
-** INVARIANTS:
-** 
-** {F10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
-**          will enable or disable shared cache mode for any subsequently
-**          created [database connection] in the same process.
-**
-** {F10336} When shared cache is enabled, the [sqlite3_create_module()]
-**          interface will always return an error.
-**
-** {F10337} The [sqlite3_enable_shared_cache(B)] interface returns
-**          [SQLITE_OK] if shared cache was enabled or disabled successfully.
+** See Also:  [SQLite Shared-Cache Mode]
 **
-** {F10339} Shared cache is disabled by default.
+** Requirements: [H10331] [H10336] [H10337] [H10339]
 */
 SQLITE_API int sqlite3_enable_shared_cache(int);
 
 /*
-** CAPI3REF:  Attempt To Free Heap Memory {F17340}
+** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
 **
-** The sqlite3_release_memory() interface attempts to
-** free N bytes of heap memory by deallocating non-essential memory
-** allocations held by the database labrary. {END}  Memory used
-** to cache database pages to improve performance is an example of
-** non-essential memory.  Sqlite3_release_memory() returns
-** the number of bytes actually freed, which might be more or less
-** than the amount requested.
+** The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library. {END}  Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
 **
-** INVARIANTS:
-**
-** {F17341} The [sqlite3_release_memory(N)] interface attempts to
-**          free N bytes of heap memory by deallocating non-essential
-**          memory allocations held by the database labrary.
-**
-** {F16342} The [sqlite3_release_memory(N)] returns the number
-**          of bytes actually freed, which might be more or less
-**          than the amount requested.
+** Requirements: [H17341] [H17342]
 */
 SQLITE_API int sqlite3_release_memory(int);
 
 /*
-** CAPI3REF:  Impose A Limit On Heap Size {F17350}
+** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
 **
-** The sqlite3_soft_heap_limit() interface
-** places a "soft" limit on the amount of heap memory that may be allocated
-** by SQLite. If an internal allocation is requested 
-** that would exceed the soft heap limit, [sqlite3_release_memory()] is
-** invoked one or more times to free up some space before the allocation
-** is made.
+** The sqlite3_soft_heap_limit() interface places a "soft" limit
+** on the amount of heap memory that may be allocated by SQLite.
+** If an internal allocation is requested that would exceed the
+** soft heap limit, [sqlite3_release_memory()] is invoked one or
+** more times to free up some space before the allocation is performed.
 **
-** The limit is called "soft", because if
-** [sqlite3_release_memory()] cannot
-** free sufficient memory to prevent the limit from being exceeded,
+** The limit is called "soft", because if [sqlite3_release_memory()]
+** cannot free sufficient memory to prevent the limit from being exceeded,
 ** the memory is allocated anyway and the current operation proceeds.
 **
 ** A negative or zero value for N means that there is no soft heap limit and
 ** [sqlite3_release_memory()] will only be called when memory is exhausted.
 ** The default value for the soft heap limit is zero.
 **
-** SQLite makes a best effort to honor the soft heap limit.  
-** But if the soft heap limit cannot honored, execution will
-** continue without error or notification.  This is why the limit is 
+** SQLite makes a best effort to honor the soft heap limit.
+** But if the soft heap limit cannot be honored, execution will
+** continue without error or notification.  This is why the limit is
 ** called a "soft" limit.  It is advisory only.
 **
 ** Prior to SQLite version 3.5.0, this routine only constrained the memory
@@ -5068,83 +4561,56 @@ SQLITE_API int sqlite3_release_memory(int);
 ** version 3.5.0 there is no mechanism for limiting the heap usage for
 ** individual threads.
 **
-** INVARIANTS:
-**
-** {F16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
-**          of N bytes on the amount of heap memory that may be allocated
-**          using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
-**          in time.
-**
-** {F16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
-**          cause the total amount of allocated memory to exceed the
-**          soft heap limit, then [sqlite3_release_memory()] is invoked
-**          in an attempt to reduce the memory usage prior to proceeding
-**          with the memory allocation attempt.
-**
-** {F16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
-**          attempts to reduce memory usage through the soft heap limit
-**          mechanism continue even if the attempt to reduce memory
-**          usage is unsuccessful.
-**
-** {F16354} A negative or zero value for N in a call to
-**          [sqlite3_soft_heap_limit(N)] means that there is no soft
-**          heap limit and [sqlite3_release_memory()] will only be
-**          called when memory is completely exhausted.
-**
-** {F16355} The default value for the soft heap limit is zero.
-**
-** {F16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
-**          values set by all prior calls.
+** Requirements:
+** [H16351] [H16352] [H16353] [H16354] [H16355] [H16358]
 */
 SQLITE_API void sqlite3_soft_heap_limit(int);
 
 /*
-** CAPI3REF:  Extract Metadata About A Column Of A Table {F12850}
+** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
 **
-** This routine
-** returns meta-data about a specific column of a specific database
-** table accessible using the connection handle passed as the first function 
-** argument.
+** This routine returns metadata about a specific column of a specific
+** database table accessible using the [database connection] handle
+** passed as the first function argument.
 **
-** The column is identified by the second, third and fourth parameters to 
+** The column is identified by the second, third and fourth parameters to
 ** this function. The second parameter is either the name of the database
 ** (i.e. "main", "temp" or an attached database) containing the specified
 ** table or NULL. If it is NULL, then all attached databases are searched
-** for the table using the same algorithm as the database engine uses to 
+** for the table using the same algorithm used by the database engine to
 ** resolve unqualified table references.
 **
-** The third and fourth parameters to this function are the table and column 
-** name of the desired column, respectively. Neither of these parameters 
+** The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively. Neither of these parameters
 ** may be NULL.
 **
-** Meta information is returned by writing to the memory locations passed as
-** the 5th and subsequent parameters to this function. Any of these 
-** arguments may be NULL, in which case the corresponding element of meta 
-** information is ommitted.
+** Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
 **
-** <pre>
-** Parameter     Output Type      Description
-** -----------------------------------
-**
-**   5th         const char*      Data type
-**   6th         const char*      Name of the default collation sequence 
-**   7th         int              True if the column has a NOT NULL constraint
-**   8th         int              True if the column is part of the PRIMARY KEY
-**   9th         int              True if the column is AUTOINCREMENT
-** </pre>
+** <blockquote>
+** <table border="1">
+** <tr><th> Parameter <th> Output<br>Type <th>  Description
 **
+** <tr><td> 5th <td> const char* <td> Data type
+** <tr><td> 6th <td> const char* <td> Name of default collation sequence
+** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
+** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
+** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
+** </table>
+** </blockquote>
 **
-** The memory pointed to by the character pointers returned for the 
-** declaration type and collation sequence is valid only until the next 
-** call to any sqlite API function.
+** The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid only until the next
+** call to any SQLite API function.
 **
-** If the specified table is actually a view, then an error is returned.
+** If the specified table is actually a view, an [error code] is returned.
 **
-** If the specified column is "rowid", "oid" or "_rowid_" and an 
-** INTEGER PRIMARY KEY column has been explicitly declared, then the output 
+** If the specified column is "rowid", "oid" or "_rowid_" and an
+** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
 ** parameters are set for the explicitly declared column. If there is no
-** explicitly declared IPK column, then the output parameters are set as 
-** follows:
+** explicitly declared [INTEGER PRIMARY KEY] column, then the output
+** parameters are set as follows:
 **
 ** <pre>
 **     data type: "INTEGER"
@@ -5156,11 +4622,11 @@ SQLITE_API void sqlite3_soft_heap_limit(int);
 **
 ** This function may load one or more schemas from database files. If an
 ** error occurs during this process, or if the requested table or column
-** cannot be found, an SQLITE error code is returned and an error message
-** left in the database handle (to be retrieved using sqlite3_errmsg()).
+** cannot be found, an [error code] is returned and an error message left
+** in the [database connection] (to be retrieved using sqlite3_errmsg()).
 **
 ** This API is only available if the library was compiled with the
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 */
 SQLITE_API int sqlite3_table_column_metadata(
   sqlite3 *db,                /* Connection handle */
@@ -5175,27 +4641,30 @@ SQLITE_API int sqlite3_table_column_metadata(
 );
 
 /*
-** CAPI3REF: Load An Extension {F12600}
+** CAPI3REF: Load An Extension {H12600} <S20500>
 **
-** {F12601} The sqlite3_load_extension() interface
-** attempts to load an SQLite extension library contained in the file
-** zFile. {F12602} The entry point is zProc. {F12603} zProc may be 0
-** in which case the name of the entry point defaults
-** to "sqlite3_extension_init".
+** This interface loads an SQLite extension library from the named file.
 **
-** {F12604} The sqlite3_load_extension() interface shall
-** return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** {H12601} The sqlite3_load_extension() interface attempts to load an
+**          SQLite extension library contained in the file zFile.
 **
-** {F12605}
-** If an error occurs and pzErrMsg is not 0, then the
-** sqlite3_load_extension() interface shall attempt to fill *pzErrMsg with 
-** error message text stored in memory obtained from [sqlite3_malloc()].
-** {END}  The calling function should free this memory
-** by calling [sqlite3_free()].
+** {H12602} The entry point is zProc.
 **
-** {F12606}
-** Extension loading must be enabled using [sqlite3_enable_load_extension()]
-** prior to calling this API or an error will be returned.
+** {H12603} zProc may be 0, in which case the name of the entry point
+**          defaults to "sqlite3_extension_init".
+**
+** {H12604} The sqlite3_load_extension() interface shall return
+**          [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+**
+** {H12605} If an error occurs and pzErrMsg is not 0, then the
+**          [sqlite3_load_extension()] interface shall attempt to
+**          fill *pzErrMsg with error message text stored in memory
+**          obtained from [sqlite3_malloc()]. {END}  The calling function
+**          should free this memory by calling [sqlite3_free()].
+**
+** {H12606} Extension loading must be enabled using
+**          [sqlite3_enable_load_extension()] prior to calling this API,
+**          otherwise an error will be returned.
 */
 SQLITE_API int sqlite3_load_extension(
   sqlite3 *db,          /* Load the extension into this database connection */
@@ -5205,65 +4674,64 @@ SQLITE_API int sqlite3_load_extension(
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Extension Loading {F12620}
+** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
 **
 ** So as not to open security holes in older applications that are
 ** unprepared to deal with extension loading, and as a means of disabling
-** extension loading while evaluating user-entered SQL, the following
-** API is provided to turn the [sqlite3_load_extension()] mechanism on and
-** off.  {F12622} It is off by default. {END} See ticket #1863.
+** extension loading while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
 **
-** {F12621} Call the sqlite3_enable_load_extension() routine
-** with onoff==1 to turn extension loading on
-** and call it with onoff==0 to turn it back off again. {END}
+** Extension loading is off by default. See ticket #1863.
+**
+** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
+**          to turn extension loading on and call it with onoff==0 to turn
+**          it back off again.
+**
+** {H12622} Extension loading is off by default.
 */
 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Make Arrangements To Automatically Load An Extension {F12640}
-**
-** {F12641} This function
-** registers an extension entry point that is automatically invoked
-** whenever a new database connection is opened using
-** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()]. {END}
+** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
 **
 ** This API can be invoked at program startup in order to register
 ** one or more statically linked extensions that will be available
-** to all new database connections.
+** to all new [database connections]. {END}
 **
-** {F12642} Duplicate extensions are detected so calling this routine multiple
-** times with the same extension is harmless.
+** This routine stores a pointer to the extension in an array that is
+** obtained from [sqlite3_malloc()].  If you run a memory leak checker
+** on your program and it reports a leak because of this array, invoke
+** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
 **
-** {F12643} This routine stores a pointer to the extension in an array
-** that is obtained from sqlite_malloc(). {END} If you run a memory leak
-** checker on your program and it reports a leak because of this
-** array, then invoke [sqlite3_reset_auto_extension()] prior
-** to shutdown to free the memory.
+** {H12641} This function registers an extension entry point that is
+**          automatically invoked whenever a new [database connection]
+**          is opened using [sqlite3_open()], [sqlite3_open16()],
+**          or [sqlite3_open_v2()].
 **
-** {F12644} Automatic extensions apply across all threads. {END}
+** {H12642} Duplicate extensions are detected so calling this routine
+**          multiple times with the same extension is harmless.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12643} This routine stores a pointer to the extension in an array
+**          that is obtained from [sqlite3_malloc()].
+**
+** {H12644} Automatic extensions apply across all threads.
 */
-SQLITE_API int sqlite3_auto_extension(void *xEntryPoint);
-
+SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
 /*
-** CAPI3REF: Reset Automatic Extension Loading {F12660}
+** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
 **
-** {F12661} This function disables all previously registered
-** automatic extensions. {END}  This
-** routine undoes the effect of all prior [sqlite3_auto_extension()]
-** calls.
+** This function disables all previously registered automatic
+** extensions. {END}  It undoes the effect of all prior
+** [sqlite3_auto_extension()] calls.
 **
-** {F12662} This call disabled automatic extensions in all threads. {END}
+** {H12661} This function disables all previously registered
+**          automatic extensions.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12662} This function disables automatic extensions in all threads.
 */
 SQLITE_API void sqlite3_reset_auto_extension(void);
 
-
 /*
 ****** EXPERIMENTAL - subject to change without notice **************
 **
@@ -5271,7 +4739,7 @@ SQLITE_API void sqlite3_reset_auto_extension(void);
 ** to be experimental.  The interface might change in incompatible ways.
 ** If this is a problem for you, do not use the interface at this time.
 **
-** When the virtual-table mechanism stablizes, we will declare the
+** When the virtual-table mechanism stabilizes, we will declare the
 ** interface fixed, support it indefinitely, and remove this comment.
 */
 
@@ -5284,12 +4752,21 @@ typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
 
 /*
-** CAPI3REF: Virtual Table Object {F18000}
-** KEYWORDS: sqlite3_module
+** CAPI3REF: Virtual Table Object {H18000} <S20400>
+** KEYWORDS: sqlite3_module {virtual table module}
+** EXPERIMENTAL
+**
+** This structure, sometimes called a a "virtual table module", 
+** defines the implementation of a [virtual tables].  
+** This structure consists mostly of methods for the module.
 **
-** A module is a class of virtual tables.  Each module is defined
-** by an instance of the following structure.  This structure consists
-** mostly of methods for the module.
+** A virtual table module is created by filling in a persistent
+** instance of this structure and passing a pointer to that instance
+** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
+** The registration remains valid until it is replaced by a different
+** module or until the [database connection] closes.  The content
+** of this structure must not change while it is registered with
+** any database connection.
 */
 struct sqlite3_module {
   int iVersion;
@@ -5318,28 +4795,26 @@ struct sqlite3_module {
   int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
                        void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                        void **ppArg);
-
   int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
 };
 
 /*
-** CAPI3REF: Virtual Table Indexing Information {F18100}
+** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
 ** KEYWORDS: sqlite3_index_info
+** EXPERIMENTAL
 **
 ** The sqlite3_index_info structure and its substructures is used to
-** pass information into and receive the reply from the xBestIndex
-** method of an sqlite3_module.  The fields under **Inputs** are the
+** pass information into and receive the reply from the [xBestIndex]
+** method of a [virtual table module].  The fields under **Inputs** are the
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
 ** results into the **Outputs** fields.
 **
-** The aConstraint[] array records WHERE clause constraints of the
-** form:
+** The aConstraint[] array records WHERE clause constraints of the form:
 **
-**         column OP expr
+** <pre>column OP expr</pre>
 **
-** Where OP is =, &lt;, &lt;=, &gt;, or &gt;=.  
-** The particular operator is stored
-** in aConstraint[].op.  The index of the column is stored in 
+** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.  The particular operator is
+** stored in aConstraint[].op.  The index of the column is stored in
 ** aConstraint[].iColumn.  aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.
@@ -5353,17 +4828,19 @@ struct sqlite3_module {
 ** Information about the ORDER BY clause is stored in aOrderBy[].
 ** Each term of aOrderBy records a column of the ORDER BY clause.
 **
-** The xBestIndex method must fill aConstraintUsage[] with information
+** The [xBestIndex] method must fill aConstraintUsage[] with information
 ** about what parameters to pass to xFilter.  If argvIndex>0 then
 ** the right-hand side of the corresponding aConstraint[] is evaluated
 ** and becomes the argvIndex-th entry in argv.  If aConstraintUsage[].omit
 ** is true, then the constraint is assumed to be fully handled by the
 ** virtual table and is not checked again by SQLite.
 **
-** The idxNum and idxPtr values are recorded and passed into xFilter.
-** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
+** The idxNum and idxPtr values are recorded and passed into the
+** [xFilter] method.
+** [sqlite3_free()] is used to free idxPtr if and only iff
+** needToFreeIdxPtr is true.
 **
-** The orderByConsumed means that output from xFilter will occur in
+** The orderByConsumed means that output from [xFilter]/[xNext] will occur in
 ** the correct order to satisfy the ORDER BY clause so that no separate
 ** sorting step is required.
 **
@@ -5386,7 +4863,6 @@ struct sqlite3_index_info {
      int iColumn;              /* Column number */
      unsigned char desc;       /* True for DESC.  False for ASC. */
   } *aOrderBy;               /* The ORDER BY clause */
-
   /* Outputs */
   struct sqlite3_index_constraint_usage {
     int argvIndex;           /* if >0, constraint is part of argv to xFilter */
@@ -5406,70 +4882,89 @@ struct sqlite3_index_info {
 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18200}
+** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
+** EXPERIMENTAL
 **
-** This routine is used to register a new module name with an SQLite
-** connection.  Module names must be registered before creating new
-** virtual tables on the module, or before using preexisting virtual
-** tables of the module.
+** This routine is used to register a new [virtual table module] name.
+** Module names must be registered before
+** creating a new [virtual table] using the module, or before using a
+** preexisting [virtual table] for the module.
+**
+** The module name is registered on the [database connection] specified
+** by the first parameter.  The name of the module is given by the 
+** second parameter.  The third parameter is a pointer to
+** the implementation of the [virtual table module].   The fourth
+** parameter is an arbitrary client data pointer that is passed through
+** into the [xCreate] and [xConnect] methods of the virtual table module
+** when a new virtual table is be being created or reinitialized.
+**
+** This interface has exactly the same effect as calling
+** [sqlite3_create_module_v2()] with a NULL client data destructor.
 */
-SQLITE_API int sqlite3_create_module(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
-  const sqlite3_module *,    /* Methods for the module */
-  void *                     /* Client data for xCreate/xConnect */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData          /* Client data for xCreate/xConnect */
 );
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18210}
+** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
+** EXPERIMENTAL
 **
-** This routine is identical to the sqlite3_create_module() method above,
-** except that it allows a destructor function to be specified. It is
-** even more experimental than the rest of the virtual tables API.
+** This routine is identical to the [sqlite3_create_module()] method,
+** except that it has an extra parameter to specify 
+** a destructor function for the client data pointer.  SQLite will
+** invoke the destructor function (if it is not NULL) when SQLite
+** no longer needs the pClientData pointer.  
 */
-SQLITE_API int sqlite3_create_module_v2(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
-  const sqlite3_module *,    /* Methods for the module */
-  void *,                    /* Client data for xCreate/xConnect */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData,         /* Client data for xCreate/xConnect */
   void(*xDestroy)(void*)     /* Module destructor function */
 );
 
 /*
-** CAPI3REF: Virtual Table Instance Object {F18010}
+** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
 ** KEYWORDS: sqlite3_vtab
+** EXPERIMENTAL
 **
-** Every module implementation uses a subclass of the following structure
-** to describe a particular instance of the module.  Each subclass will
-** be tailored to the specific needs of the module implementation.   The
-** purpose of this superclass is to define certain fields that are common
-** to all module implementations.
+** Every [virtual table module] implementation uses a subclass
+** of the following structure to describe a particular instance
+** of the [virtual table].  Each subclass will
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
 **
 ** Virtual tables methods can set an error message by assigning a
-** string obtained from sqlite3_mprintf() to zErrMsg.  The method should
-** take care that any prior string is freed by a call to sqlite3_free()
+** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
 ** prior to assigning a new string to zErrMsg.  After the error message
 ** is delivered up to the client application, the string will be automatically
-** freed by sqlite3_free() and the zErrMsg field will be zeroed.  Note
-** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
-** since virtual tables are commonly implemented in loadable extensions which
-** do not have access to sqlite3MPrintf() or sqlite3Free().
+** freed by sqlite3_free() and the zErrMsg field will be zeroed.
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;  /* The module for this virtual table */
-  int nRef;                       /* Used internally */
+  int nRef;                       /* NO LONGER USED */
   char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
   /* Virtual table implementations will typically add additional fields */
 };
 
 /*
-** CAPI3REF: Virtual Table Cursor Object  {F18020}
-** KEYWORDS: sqlite3_vtab_cursor
+** CAPI3REF: Virtual Table Cursor Object  {H18020} <S20400>
+** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
+** EXPERIMENTAL
 **
-** Every module implementation uses a subclass of the following structure
-** to describe cursors that point into the virtual table and are used
+** Every [virtual table module] implementation uses a subclass of the
+** following structure to describe cursors that point into the
+** [virtual table] and are used
 ** to loop through the virtual table.  Cursors are created using the
-** xOpen method of the module.  Each module implementation will define
+** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
+** by the [sqlite3_module.xClose | xClose] method.  Cussors are used
+** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
+** of the module.  Each module implementation will define
 ** the content of a cursor structure to suit its own needs.
 **
 ** This superclass exists in order to define fields of the cursor that
@@ -5481,19 +4976,23 @@ struct sqlite3_vtab_cursor {
 };
 
 /*
-** CAPI3REF: Declare The Schema Of A Virtual Table {F18280}
+** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
+** EXPERIMENTAL
 **
-** The xCreate and xConnect methods of a module use the following API
+** The [xCreate] and [xConnect] methods of a
+** [virtual table module] call this interface
 ** to declare the format (the names and datatypes of the columns) of
 ** the virtual tables they implement.
 */
-SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
 
 /*
-** CAPI3REF: Overload A Function For A Virtual Table {F18300}
+** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
+** EXPERIMENTAL
 **
 ** Virtual tables can provide alternative implementations of functions
-** using the xFindFunction method.  But global versions of those functions
+** using the [xFindFunction] method of the [virtual table module].  
+** But global versions of those functions
 ** must exist in order to be overloaded.
 **
 ** This API makes sure a global version of a function with a particular
@@ -5501,13 +5000,10 @@ SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
 ** before this API is called, a new function is created.  The implementation
 ** of the new function always causes an exception to be thrown.  So
 ** the new function is not good for anything by itself.  Its only
-** purpose is to be a place-holder function that can be overloaded
-** by virtual tables.
-**
-** This API should be considered part of the virtual table interface,
-** which is experimental and subject to change.
+** purpose is to be a placeholder function that can be overloaded
+** by a [virtual table].
 */
-SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
 
 /*
 ** The interface to the virtual-table mechanism defined above (back up
@@ -5522,68 +5018,77 @@ SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nA
 */
 
 /*
-** CAPI3REF: A Handle To An Open BLOB {F17800}
+** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
+** KEYWORDS: {BLOB handle} {BLOB handles}
 **
 ** An instance of this object represents an open BLOB on which
-** incremental I/O can be preformed.
-** Objects of this type are created by
-** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
 ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
-** can be used to read or write small subsections of the blob.
-** The [sqlite3_blob_bytes()] interface returns the size of the
-** blob in bytes.
+** can be used to read or write small subsections of the BLOB.
+** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
 */
 typedef struct sqlite3_blob sqlite3_blob;
 
 /*
-** CAPI3REF: Open A BLOB For Incremental I/O {F17810}
+** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
 **
-** This interfaces opens a handle to the blob located
+** This interfaces opens a [BLOB handle | handle] to the BLOB located
 ** in row iRow, column zColumn, table zTable in database zDb;
-** in other words,  the same blob that would be selected by:
+** in other words, the same BLOB that would be selected by:
 **
 ** <pre>
-**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
+**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
 ** </pre> {END}
 **
-** If the flags parameter is non-zero, the blob is opened for 
-** read and write access. If it is zero, the blob is opened for read 
-** access.
+** If the flags parameter is non-zero, then the BLOB is opened for read
+** and write access. If it is zero, the BLOB is opened for read access.
+** It is not possible to open a column that is part of an index or primary 
+** key for writing. ^If [foreign key constraints] are enabled, it is 
+** not possible to open a column that is part of a [child key] for writing.
 **
 ** Note that the database name is not the filename that contains
 ** the database but rather the symbolic name of the database that
 ** is assigned when the database is connected using [ATTACH].
-** For the main database file, the database name is "main".  For
-** TEMP tables, the database name is "temp".
-**
-** On success, [SQLITE_OK] is returned and the new 
-** [sqlite3_blob | blob handle] is written to *ppBlob. 
-** Otherwise an error code is returned and 
-** any value written to *ppBlob should not be used by the caller.
-** This function sets the database-handle error code and message
-** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
-** 
-** INVARIANTS:
-**
-** {F17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
-**          interface opens an [sqlite3_blob] object P on the blob
-**          in column C of table T in database B on [database connection] D.
-**
-** {F17814} A successful invocation of [sqlite3_blob_open(D,...)] starts
-**          a new transaction on [database connection] D if that connection
-**          is not already in a transaction.
-**
-** {F17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface opens the blob
-**          for read and write access if and only if the F parameter
-**          is non-zero.
-**
-** {F17819} The [sqlite3_blob_open()] interface returns [SQLITE_OK] on 
-**          success and an appropriate [error code] on failure.
-**
-** {F17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+** For the main database file, the database name is "main".
+** For TEMP tables, the database name is "temp".
+**
+** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
+** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
+** to be a null pointer.
+** This function sets the [database connection] error code and message
+** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
+** functions.  Note that the *ppBlob variable is always initialized in a
+** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
+** regardless of the success or failure of this routine.
+**
+** If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.
+** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
+** Changes written into a BLOB prior to the BLOB expiring are not
+** rollback by the expiration of the BLOB.  Such changes will eventually
+** commit if the transaction continues to completion.
+**
+** Use the [sqlite3_blob_bytes()] interface to determine the size of
+** the opened blob.  The size of a blob may not be changed by this
+** interface.  Use the [UPDATE] SQL command to change the size of a
+** blob.
+**
+** The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
+** and the built-in [zeroblob] SQL function can be used, if desired,
+** to create an empty, zero-filled blob in which to read or write using
+** this interface.
+**
+** To avoid a resource leak, every open [BLOB handle] should eventually
+** be released by a call to [sqlite3_blob_close()].
+**
+** Requirements:
+** [H17813] [H17814] [H17816] [H17819] [H17821] [H17824]
 */
 SQLITE_API int sqlite3_blob_open(
   sqlite3*,
@@ -5596,158 +5101,125 @@ SQLITE_API int sqlite3_blob_open(
 );
 
 /*
-** CAPI3REF:  Close A BLOB Handle {F17830}
+** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
 **
-** Close an open [sqlite3_blob | blob handle].
+** Closes an open [BLOB handle].
 **
 ** Closing a BLOB shall cause the current transaction to commit
 ** if there are no other BLOBs, no pending prepared statements, and the
-** database connection is in autocommit mode.
+** database connection is in [autocommit mode].
 ** If any writes were made to the BLOB, they might be held in cache
-** until the close operation if they will fit. {END}
+** until the close operation if they will fit.
+**
 ** Closing the BLOB often forces the changes
 ** out to disk and so if any I/O errors occur, they will likely occur
-** at the time when the BLOB is closed.  {F17833} Any errors that occur during
+** at the time when the BLOB is closed.  Any errors that occur during
 ** closing are reported as a non-zero return value.
 **
 ** The BLOB is closed unconditionally.  Even if this routine returns
 ** an error code, the BLOB is still closed.
 **
-** INVARIANTS:
-**
-** {F17833} The [sqlite3_blob_close(P)] interface closes an
-**          [sqlite3_blob] object P previously opened using
-**          [sqlite3_blob_open()].
-**
-** {F17836} Closing an [sqlite3_blob] object using
-**          [sqlite3_blob_close()] shall cause the current transaction to
-**          commit if there are no other open [sqlite3_blob] objects
-**          or [prepared statements] on the same [database connection] and
-**          the [database connection] is in
-**          [sqlite3_get_autocommit | autocommit mode].
+** Calling this routine with a null pointer (which as would be returned
+** by failed call to [sqlite3_blob_open()]) is a harmless no-op.
 **
-** {F17839} The [sqlite3_blob_close(P)] interfaces closes the 
-**          [sqlite3_blob] object P unconditionally, even if
-**          [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
-**          
+** Requirements:
+** [H17833] [H17836] [H17839]
 */
 SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Return The Size Of An Open BLOB {F17840}
+** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
 **
-** Return the size in bytes of the blob accessible via the open 
-** [sqlite3_blob] object in its only argument.
+** Returns the size in bytes of the BLOB accessible via the 
+** successfully opened [BLOB handle] in its only argument.  The
+** incremental blob I/O routines can only read or overwriting existing
+** blob content; they cannot change the size of a blob.
 **
-** INVARIANTS:
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17843} The [sqlite3_blob_bytes(P)] interface returns the size
-**          in bytes of the BLOB that the [sqlite3_blob] object P
-**          refers to.
+** Requirements:
+** [H17843]
 */
 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Read Data From A BLOB Incrementally {F17850}
+** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
 **
-** This function is used to read data from an open 
-** [sqlite3_blob | blob-handle] into a caller supplied buffer.
-** N bytes of data are copied into buffer
-** Z from the open blob, starting at offset iOffset.
+** This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.
 **
-** If offset iOffset is less than N bytes from the end of the blob, 
+** If offset iOffset is less than N bytes from the end of the BLOB,
 ** [SQLITE_ERROR] is returned and no data is read.  If N or iOffset is
-** less than zero [SQLITE_ERROR] is returned and no data is read.
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
+** The size of the blob (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
+** An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
 **
-** INVARIANTS:
+** On success, SQLITE_OK is returned.
+** Otherwise, an [error code] or an [extended error code] is returned.
 **
-** {F17853} The [sqlite3_blob_read(P,Z,N,X)] interface reads N bytes
-**          beginning at offset X from
-**          the blob that [sqlite3_blob] object P refers to
-**          and writes those N bytes into buffer Z.
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
+** See also: [sqlite3_blob_write()].
 **
-** {F17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
-**
-** {F17862} The [sqlite3_blob_read(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully read into buffer Z.
-**
-** {F17865} If the requested read could not be completed,
-**          the [sqlite3_blob_read(P,Z,N,X)] interface returns an
-**          appropriate [error code] or [extended error code].
-**
-** {F17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error, where D is the
-**          database handle that was used to open blob handle P.
+** Requirements:
+** [H17853] [H17856] [H17859] [H17862] [H17863] [H17865] [H17868]
 */
 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
 
 /*
-** CAPI3REF:  Write Data Into A BLOB Incrementally {F17870}
+** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
 **
-** This function is used to write data into an open 
-** [sqlite3_blob | blob-handle] from a user supplied buffer.
-** n bytes of data are copied from the buffer
-** pointed to by z into the open blob, starting at offset iOffset.
+** This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.
 **
-** If the [sqlite3_blob | blob-handle] passed as the first argument
-** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
-*** was zero), this function returns [SQLITE_READONLY].
+** If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
 **
-** This function may only modify the contents of the blob; it is
-** not possible to increase the size of a blob using this API.
-** If offset iOffset is less than n bytes from the end of the blob, 
-** [SQLITE_ERROR] is returned and no data is written.  If n is
+** This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written.  If N is
 ** less than zero [SQLITE_ERROR] is returned and no data is written.
+** The size of the BLOB (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
-**
-** INVARIANTS:
-**
-** {F17873} The [sqlite3_blob_write(P,Z,N,X)] interface writes N bytes
-**          from buffer Z into
-**          the blob that [sqlite3_blob] object P refers to
-**          beginning at an offset of X into the blob.
+** An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].  Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
 **
-** {F17875} The [sqlite3_blob_write(P,Z,N,X)] interface returns
-**          [SQLITE_READONLY] if the [sqlite3_blob] object P was
-**          [sqlite3_blob_open | opened] for reading only.
+** On success, SQLITE_OK is returned.
+** Otherwise, an  [error code] or an [extended error code] is returned.
 **
-** {F17876} In [sqlite3_blob_write(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17879} In [sqlite3_blob_write(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** See also: [sqlite3_blob_read()].
 **
-** {F17882} The [sqlite3_blob_write(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully written into blob.
-**
-** {F17885} If the requested write could not be completed,
-**          the [sqlite3_blob_write(P,Z,N,X)] interface returns an
-**          appropriate [error code] or [extended error code].
-**
-** {F17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+** Requirements:
+** [H17873] [H17874] [H17875] [H17876] [H17877] [H17879] [H17882] [H17885]
+** [H17888]
 */
 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
 
 /*
-** CAPI3REF:  Virtual File System Objects {F11200}
+** CAPI3REF: Virtual File System Objects {H11200} <S20100>
 **
 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
 ** that SQLite uses to interact
@@ -5756,12 +5228,11 @@ SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOff
 ** New VFSes can be registered and existing VFSes can be unregistered.
 ** The following interfaces are provided.
 **
-** The sqlite3_vfs_find() interface returns a pointer to 
-** a VFS given its name.  Names are case sensitive.
+** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** Names are case sensitive.
 ** Names are zero-terminated UTF-8 strings.
-** If there is no match, a NULL
-** pointer is returned.  If zVfsName is NULL then the default 
-** VFS is returned. 
+** If there is no match, a NULL pointer is returned.
+** If zVfsName is NULL then the default VFS is returned.
 **
 ** New VFSes are registered with sqlite3_vfs_register().
 ** Each new VFS becomes the default VFS if the makeDflt flag is set.
@@ -5771,51 +5242,27 @@ SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOff
 ** same name are registered, the behavior is undefined.  If a
 ** VFS is registered with a name that is NULL or an empty string,
 ** then the behavior is undefined.
-** 
+**
 ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
 ** If the default VFS is unregistered, another VFS is chosen as
 ** the default.  The choice for the new VFS is arbitrary.
 **
-** INVARIANTS:
-**
-** {F11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
-**          registered [sqlite3_vfs] object whose name exactly matches
-**          the zero-terminated UTF-8 string N, or it returns NULL if
-**          there is no match.
-**
-** {F11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
-**          the function returns a pointer to the default [sqlite3_vfs]
-**          object if there is one, or NULL if there is no default 
-**          [sqlite3_vfs] object.
-**
-** {F11209} The [sqlite3_vfs_register(P,F)] interface registers the
-**          well-formed [sqlite3_vfs] object P using the name given
-**          by the zName field of the object.
-**
-** {F11212} Using the [sqlite3_vfs_register(P,F)] interface to register
-**          the same [sqlite3_vfs] object multiple times is a harmless no-op.
-**
-** {F11215} The [sqlite3_vfs_register(P,F)] interface makes the
-**          the [sqlite3_vfs] object P the default [sqlite3_vfs] object
-**          if F is non-zero.
-**
-** {F11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
-**          [sqlite3_vfs] object P so that it is no longer returned by
-**          subsequent calls to [sqlite3_vfs_find()].
+** Requirements:
+** [H11203] [H11206] [H11209] [H11212] [H11215] [H11218]
 */
 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 
 /*
-** CAPI3REF: Mutexes {F17000}
+** CAPI3REF: Mutexes {H17000} <S20000>
 **
 ** The SQLite core uses these routines for thread
-** synchronization.  Though they are intended for internal
+** synchronization. Though they are intended for internal
 ** use by SQLite, code that links against SQLite is
 ** permitted to use any of these routines.
 **
-** The SQLite source code contains multiple implementations 
+** The SQLite source code contains multiple implementations
 ** of these mutex routines.  An appropriate implementation
 ** is selected automatically at compile-time.  The following
 ** implementations are available in the SQLite core:
@@ -5827,25 +5274,24 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** <li>   SQLITE_MUTEX_NOOP
 ** </ul>
 **
-** The SQLITE_MUTEX_NOOP implementation is a set of routines 
-** that does no real locking and is appropriate for use in 
+** The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
 ** a single-threaded application.  The SQLITE_MUTEX_OS2,
 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
-** are appropriate for use on os/2, unix, and windows.
-** 
+** are appropriate for use on OS/2, Unix, and Windows.
+**
 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
-** implementation is included with the library.  The
-** mutex interface routines defined here become external
-** references in the SQLite library for which implementations
-** must be provided by the application.  This facility allows an
-** application that links against SQLite to provide its own mutex
-** implementation without having to modify the SQLite core.
-**
-** {F17011} The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it. {F17012} If it returns NULL
-** that means that a mutex could not be allocated. {F17013} SQLite
-** will unwind its stack and return an error. {F17014} The argument
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().
+**
+** {H17011} The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. {H17012} If it returns NULL
+** that means that a mutex could not be allocated. {H17013} SQLite
+** will unwind its stack and return an error. {H17014} The argument
 ** to sqlite3_mutex_alloc() is one of these integer constants:
 **
 ** <ul>
@@ -5857,63 +5303,67 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** <li>  SQLITE_MUTEX_STATIC_PRNG
 ** <li>  SQLITE_MUTEX_STATIC_LRU
 ** <li>  SQLITE_MUTEX_STATIC_LRU2
-** </ul> {END}
+** </ul>
 **
-** {F17015} The first two constants cause sqlite3_mutex_alloc() to create
+** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
 ** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
 ** The mutex implementation does not need to make a distinction
 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  {F17016} But SQLite will only request a recursive mutex in
+** not want to.  {H17016} But SQLite will only request a recursive mutex in
 ** cases where it really needs one.  {END} If a faster non-recursive mutex
 ** implementation is available on the host platform, the mutex subsystem
 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
 **
-** {F17017} The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex. {END}  Four static mutexes are
+** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. {END}  Six static mutexes are
 ** used by the current version of SQLite.  Future versions of SQLite
 ** may add additional static mutexes.  Static mutexes are for internal
 ** use by SQLite only.  Applications that use SQLite mutexes should
 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
 ** SQLITE_MUTEX_RECURSIVE.
 **
-** {F17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  {F17034} But for the static 
+** returns a different mutex on every call.  {H17034} But for the static
 ** mutex types, the same mutex is returned on every call that has
-** the same type number. {END}
+** the same type number.
 **
-** {F17019} The sqlite3_mutex_free() routine deallocates a previously
-** allocated dynamic mutex. {F17020} SQLite is careful to deallocate every
-** dynamic mutex that it allocates. {U17021} The dynamic mutexes must not be in 
-** use when they are deallocated. {U17022} Attempting to deallocate a static
-** mutex results in undefined behavior. {F17023} SQLite never deallocates
+** {H17019} The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
+** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
+** use when they are deallocated. {A17022} Attempting to deallocate a static
+** mutex results in undefined behavior. {H17023} SQLite never deallocates
 ** a static mutex. {END}
 **
 ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex. {F17024} If another thread is already within the mutex,
+** to enter a mutex. {H17024} If another thread is already within the mutex,
 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY. {F17025}  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  {F17026} Mutexes created using
+** SQLITE_BUSY. {H17025}  The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry.  {H17026} Mutexes created using
 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
-** {F17027} In such cases the,
+** {H17027} In such cases the,
 ** mutex must be exited an equal number of times before another thread
-** can enter.  {U17028} If the same thread tries to enter any other
+** can enter.  {A17028} If the same thread tries to enter any other
 ** kind of mutex more than once, the behavior is undefined.
-** {F17029} SQLite will never exhibit
-** such behavior in its own use of mutexes. {END}
+** {H17029} SQLite will never exhibit
+** such behavior in its own use of mutexes.
 **
-** Some systems (ex: windows95) do not the operation implemented by
-** sqlite3_mutex_try().  On those systems, sqlite3_mutex_try() will
-** always return SQLITE_BUSY.  {F17030} The SQLite core only ever uses
-** sqlite3_mutex_try() as an optimization so this is acceptable behavior. {END}
+** Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY.  {H17030} The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
 **
-** {F17031} The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  {U17032} The behavior
+** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread.  {A17032} The behavior
 ** is undefined if the mutex is not currently entered by the
-** calling thread or is not currently allocated.  {F17033} SQLite will
+** calling thread or is not currently allocated.  {H17033} SQLite will
 ** never do either. {END}
 **
+** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
 */
 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
@@ -5923,73 +5373,166 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Verifcation Routines {F17080}
+** CAPI3REF: Mutex Methods Object {H17120} <S20130>
+** EXPERIMENTAL
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the user has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the user
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** {H17001} The xMutexInit routine shall be called by SQLite once for each
+** effective call to [sqlite3_initialize()].
+**
+** The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
+** interface shall be invoked once for each call to [sqlite3_shutdown()].
+**
+** The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+** <ul>
+**   <li>  [sqlite3_mutex_alloc()] </li>
+**   <li>  [sqlite3_mutex_free()] </li>
+**   <li>  [sqlite3_mutex_enter()] </li>
+**   <li>  [sqlite3_mutex_try()] </li>
+**   <li>  [sqlite3_mutex_leave()] </li>
+**   <li>  [sqlite3_mutex_held()] </li>
+**   <li>  [sqlite3_mutex_notheld()] </li>
+** </ul>
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+**
+** The xMutexInit() method must be threadsafe.  It must be harmless to
+** invoke xMutexInit() mutiple times within the same process and without
+** intervening calls to xMutexEnd().  Second and subsequent calls to
+** xMutexInit() must be no-ops.
+**
+** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
+** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
+** allocation for a static mutex.  However xMutexAlloc() may use SQLite
+** memory allocation for a fast or recursive mutex.
+**
+** SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
+** called, but only if the prior call to xMutexInit returned SQLITE_OK.
+** If xMutexInit fails in any way, it is expected to clean up after itself
+** prior to returning.
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+  int (*xMutexInit)(void);
+  int (*xMutexEnd)(void);
+  sqlite3_mutex *(*xMutexAlloc)(int);
+  void (*xMutexFree)(sqlite3_mutex *);
+  void (*xMutexEnter)(sqlite3_mutex *);
+  int (*xMutexTry)(sqlite3_mutex *);
+  void (*xMutexLeave)(sqlite3_mutex *);
+  int (*xMutexHeld)(sqlite3_mutex *);
+  int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
 **
 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
-** are intended for use inside assert() statements. {F17081} The SQLite core
+** are intended for use inside assert() statements. {H17081} The SQLite core
 ** never uses these routines except inside an assert() and applications
-** are advised to follow the lead of the core.  {F17082} The core only
+** are advised to follow the lead of the core.  {H17082} The core only
 ** provides implementations for these routines when it is compiled
-** with the SQLITE_DEBUG flag.  {U17087} External mutex implementations
+** with the SQLITE_DEBUG flag.  {A17087} External mutex implementations
 ** are only required to provide these routines if SQLITE_DEBUG is
 ** defined and if NDEBUG is not defined.
 **
-** {F17083} These routines should return true if the mutex in their argument
-** is held or not held, respectively, by the calling thread. {END}
+** {H17083} These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
 **
 ** {X17084} The implementation is not required to provided versions of these
-** routines that actually work.
-** If the implementation does not provide working
-** versions of these routines, it should at least provide stubs
-** that always return true so that one does not get spurious
-** assertion failures. {END}
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
 **
-** {F17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
+** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
 ** the routine should return 1.  {END} This seems counter-intuitive since
 ** clearly the mutex cannot be held if it does not exist.  But the
 ** the reason the mutex does not exist is because the build is not
 ** using mutexes.  And we do not want the assert() containing the
 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
-** the appropriate thing to do.  {F17086} The sqlite3_mutex_notheld() 
+** the appropriate thing to do.  {H17086} The sqlite3_mutex_notheld()
 ** interface should also return 1 when given a NULL pointer.
 */
 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Types {F17001}
+** CAPI3REF: Mutex Types {H17001} <H17000>
 **
-** {F17002} The [sqlite3_mutex_alloc()] interface takes a single argument
-** which is one of these integer constants. {END}
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
+**
+** The set of static mutexes may change from one SQLite release to the
+** next.  Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
 */
 #define SQLITE_MUTEX_FAST             0
 #define SQLITE_MUTEX_RECURSIVE        1
 #define SQLITE_MUTEX_STATIC_MASTER    2
 #define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
-#define SQLITE_MUTEX_STATIC_MEM2      4  /* sqlite3_release_memory() */
+#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
+#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
 #define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
 #define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
 #define SQLITE_MUTEX_STATIC_LRU2      7  /* lru page list */
 
 /*
-** CAPI3REF: Low-Level Control Of Database Files {F11300}
+** CAPI3REF: Retrieve the mutex for a database connection {H17002} <H17000>
+**
+** This interface returns a pointer the [sqlite3_mutex] object that 
+** serializes access to the [database connection] given in the argument
+** when the [threading mode] is Serialized.
+** If the [threading mode] is Single-thread or Multi-thread then this
+** routine returns a NULL pointer.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
+
+/*
+** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
 **
-** {F11301} The [sqlite3_file_control()] interface makes a direct call to the
+** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
 ** xFileControl method for the [sqlite3_io_methods] object associated
-** with a particular database identified by the second argument. {F11302} The
+** with a particular database identified by the second argument. {H11302} The
 ** name of the database is the name assigned to the database by the
 ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
-** database. {F11303} To control the main database file, use the name "main"
-** or a NULL pointer. {F11304} The third and fourth parameters to this routine
+** database. {H11303} To control the main database file, use the name "main"
+** or a NULL pointer. {H11304} The third and fourth parameters to this routine
 ** are passed directly through to the second and third parameters of
-** the xFileControl method.  {F11305} The return value of the xFileControl
+** the xFileControl method.  {H11305} The return value of the xFileControl
 ** method becomes the return value of this routine.
 **
-** {F11306} If the second parameter (zDbName) does not match the name of any
-** open database file, then SQLITE_ERROR is returned. {F11307} This error
+** {H11306} If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned. {H11307} This error
 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
-** or [sqlite3_errmsg()]. {U11308} The underlying xFileControl method might
-** also return SQLITE_ERROR.  {U11309} There is no way to distinguish between
+** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
+** also return SQLITE_ERROR.  {A11309} There is no way to distinguish between
 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
 ** xFileControl method. {END}
 **
@@ -5998,11 +5541,11 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
 
 /*
-** CAPI3REF: Testing Interface {F11400}
+** CAPI3REF: Testing Interface {H11400} <S30800>
 **
 ** The sqlite3_test_control() interface is used to read out internal
 ** state of SQLite and to inject faults into SQLite for testing
-** purposes.  The first parameter a operation code that determines
+** purposes.  The first parameter is an operation code that determines
 ** the number, meaning, and operation of all subsequent parameters.
 **
 ** This interface is not for use by applications.  It exists solely
@@ -6017,27 +5560,727 @@ SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*
 SQLITE_API int sqlite3_test_control(int op, ...);
 
 /*
-** CAPI3REF: Testing Interface Operation Codes {F11410}
+** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
 **
 ** These constants are the valid operation code parameters used
 ** as the first argument to [sqlite3_test_control()].
 **
-** These parameters and their meansing are subject to change
+** These parameters and their meanings are subject to change
 ** without notice.  These values are for testing purposes only.
 ** Applications should not use any of these parameters or the
 ** [sqlite3_test_control()] interface.
 */
-#define SQLITE_TESTCTRL_FAULT_CONFIG             1
-#define SQLITE_TESTCTRL_FAULT_FAILURES           2
-#define SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES    3
-#define SQLITE_TESTCTRL_FAULT_PENDING            4
 #define SQLITE_TESTCTRL_PRNG_SAVE                5
 #define SQLITE_TESTCTRL_PRNG_RESTORE             6
 #define SQLITE_TESTCTRL_PRNG_RESET               7
 #define SQLITE_TESTCTRL_BITVEC_TEST              8
+#define SQLITE_TESTCTRL_FAULT_INSTALL            9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
+#define SQLITE_TESTCTRL_PENDING_BYTE            11
+#define SQLITE_TESTCTRL_ASSERT                  12
+#define SQLITE_TESTCTRL_ALWAYS                  13
+#define SQLITE_TESTCTRL_RESERVE                 14
+
+/*
+** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information
+** about the preformance of SQLite, and optionally to reset various
+** highwater marks.  The first argument is an integer code for
+** the specific parameter to measure.  Recognized integer codes
+** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
+** The current value of the parameter is returned into *pCurrent.
+** The highest recorded value is returned in *pHighwater.  If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written. Some parameters do not record the highest
+** value.  For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.
+** Other parameters record only the highwater mark and not the current
+** value.  For these latter parameters nothing is written into *pCurrent.
+**
+** This routine returns SQLITE_OK on success and a non-zero
+** [error code] on failure.
+**
+** This routine is threadsafe but is not atomic.  This routine can be
+** called while other threads are running the same or different SQLite
+** interfaces.  However the values returned in *pCurrent and
+** *pHighwater reflect the status of SQLite at different points in time
+** and it is possible that another thread might change the parameter
+** in between the times when *pCurrent and *pHighwater are written.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+
+
+/*
+** CAPI3REF: Status Parameters {H17250} <H17200>
+** EXPERIMENTAL
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+** <dl>
+** <dt>SQLITE_STATUS_MEMORY_USED</dt>
+** <dd>This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly.  The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library.  Scratch memory
+** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter.  The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
+**
+** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents).  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
+** <dd>This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using 
+** [SQLITE_CONFIG_PAGECACHE].  The
+** value returned is in pages, not in bytes.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of page cache
+** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
+** <dd>This parameter returns the number of allocations used out of the
+** [scratch memory allocator] configured using
+** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
+** in bytes.  Since a single thread may only have one scratch allocation
+** outstanding at time, this parameter also reports the number of threads
+** using scratch memory at the same time.</dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of scratch memory
+** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The values
+** returned include overflows because the requested allocation was too
+** larger (that is, because the requested allocation was larger than the
+** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
+** slots were available.
+** </dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [scratch memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_PARSER_STACK</dt>
+** <dd>This parameter records the deepest parser stack.  It is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
+** </dl>
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED          0
+#define SQLITE_STATUS_PAGECACHE_USED       1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
+#define SQLITE_STATUS_SCRATCH_USED         3
+#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
+#define SQLITE_STATUS_MALLOC_SIZE          5
+#define SQLITE_STATUS_PARSER_STACK         6
+#define SQLITE_STATUS_PAGECACHE_SIZE       7
+#define SQLITE_STATUS_SCRATCH_SIZE         8
+
+/*
+** CAPI3REF: Database Connection Status {H17500} <S60200>
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information 
+** about a single [database connection].  The first argument is the
+** database connection object to be interrogated.  The second argument
+** is the parameter to interrogate.  Currently, the only allowed value
+** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
+** Additional options will likely appear in future releases of SQLite.
+**
+** The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr.  If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
+** EXPERIMENTAL
+**
+** These constants are the available integer "verbs" that can be passed as
+** the second argument to the [sqlite3_db_status()] interface.
+**
+** New verbs may be added in future releases of SQLite. Existing verbs
+** might be discontinued. Applications should check the return code from
+** [sqlite3_db_status()] to make sure that the call worked.
+** The [sqlite3_db_status()] interface will return a non-zero error code
+** if a discontinued or unsupported verb is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
+** <dd>This parameter returns the number of lookaside memory slots currently
+** checked out.</dd>
+** </dl>
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
+
+
+/*
+** CAPI3REF: Prepared Statement Status {H17550} <S60200>
+** EXPERIMENTAL
+**
+** Each prepared statement maintains various
+** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
+** of times it has performed specific operations.  These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements.  For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.  
+**
+** This interface is used to retrieve and reset counter values from
+** a [prepared statement].  The first argument is the prepared statement
+** object to be interrogated.  The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
+** to be interrogated. 
+** The current value of the requested counter is returned.
+** If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
+** EXPERIMENTAL
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+** <dl>
+** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
+** <dd>This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan.  Large numbers for this counter
+** may indicate opportunities for performance improvement through 
+** careful use of indices.</dd>
+**
+** <dt>SQLITE_STMTSTATUS_SORT</dt>
+** <dd>This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.</dd>
+**
+** </dl>
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
+#define SQLITE_STMTSTATUS_SORT              2
+
+/*
+** CAPI3REF: Custom Page Cache Object
+** EXPERIMENTAL
+**
+** The sqlite3_pcache type is opaque.  It is implemented by
+** the pluggable module.  The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+** EXPERIMENTAL
+**
+** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
+** register an alternative page cache implementation by passing in an 
+** instance of the sqlite3_pcache_methods structure. The majority of the 
+** heap memory used by SQLite is used by the page cache to cache data read 
+** from, or ready to be written to, the database file. By implementing a 
+** custom page cache using this API, an application can control more 
+** precisely the amount of memory consumed by SQLite, the way in which 
+** that memory is allocated and released, and the policies used to 
+** determine exactly which parts of a database file are cached and for 
+** how long.
+**
+** The contents of the sqlite3_pcache_methods structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config].  Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.
+**
+** The xInit() method is called once for each call to [sqlite3_initialize()]
+** (usually only once during the lifetime of the process). It is passed
+** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set
+** up global structures and mutexes required by the custom page cache 
+** implementation. 
+**
+** The xShutdown() method is called from within [sqlite3_shutdown()], 
+** if the application invokes this API. It can be used to clean up 
+** any outstanding resources before process shutdown, if required.
+**
+** SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe.  The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  All other methods must be threadsafe
+** in multithreaded applications.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** The xCreate() method is used to construct a new cache instance.  SQLite
+** will typically create one cache instance for each open database file,
+** though this is not guaranteed. The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache.  szPage will not be a power of two.  szPage
+** will the page size of the database file that is to be cached plus an
+** increment (here called "R") of about 100 or 200.  SQLite will use the
+** extra R bytes on each page to store metadata about the underlying
+** database page on disk.  The value of R depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** R is constant for a particular build of SQLite.  The second argument to
+** xCreate(), bPurgeable, is true if the cache being created will
+** be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory.  On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** In other words, a cache created with bPurgeable set to false will
+** never contain any unpinned pages.
+**
+** The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command. As with the bPurgeable parameter,
+** the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** The xPagecount() method should return the number of pages currently
+** stored in the cache.
+** 
+** The xFetch() method is used to fetch a page and return a pointer to it. 
+** A 'page', in this context, is a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. The
+** mimimum key value is 1. After it has been retrieved using xFetch, the page 
+** is considered to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation is determined by the value of the
+** createFlag parameter passed to xFetch, according to the following table:
+**
+** <table border=1 width=85% align=center>
+** <tr><th> createFlag <th> Behaviour when page is not already in cache
+** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
+** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
+**                 Otherwise return NULL.
+** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
+**                 NULL if allocating a new page is effectively impossible.
+** </table>
+**
+** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
+** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache. After
+** attempting to unpin pages, the xFetch() method will be invoked again with
+** a createFlag of 2.
+**
+** xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument. If the third parameter, discard, is non-zero,
+** then the page should be evicted from the cache. In this case SQLite 
+** assumes that the next time the page is retrieved from the cache using
+** the xFetch() method, it will be zeroed. If the discard parameter is
+** zero, then the page is considered to be unpinned. The cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache is not required to perform any reference counting. A single 
+** call to xUnpin() unpins the page regardless of the number of prior calls 
+** to xFetch().
+**
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument from oldKey to newKey. If the cache
+** previously contains an entry associated with newKey, it should be
+** discarded. Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods
+** functions.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+  void *pArg;
+  int (*xInit)(void*);
+  void (*xShutdown)(void*);
+  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+  int (*xPagecount)(sqlite3_pcache*);
+  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+  void (*xDestroy)(sqlite3_pcache*);
+};
+
+/*
+** CAPI3REF: Online Backup Object
+** EXPERIMENTAL
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation.  The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+** EXPERIMENTAL
+**
+** This API is used to overwrite the contents of one database with that
+** of another. It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files. 
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** Exclusive access is required to the destination database for the 
+** duration of the operation. However the source database is only
+** read-locked while it is actually being read, it is not locked
+** continuously for the entire operation. Thus, the backup may be
+** performed on a live database without preventing other users from
+** writing to the database for an extended period of time.
+** 
+** To perform a backup operation: 
+**   <ol>
+**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
+**         backup, 
+**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 
+**         the data between the two databases, and finally
+**     <li><b>sqlite3_backup_finish()</b> is called to release all resources 
+**         associated with the backup operation. 
+**   </ol>
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** <b>sqlite3_backup_init()</b>
+**
+** The first two arguments passed to [sqlite3_backup_init()] are the database
+** handle associated with the destination database and the database name 
+** used to attach the destination database to the handle. The database name
+** is "main" for the main database, "temp" for the temporary database, or
+** the name specified as part of the [ATTACH] statement if the destination is
+** an attached database. The third and fourth arguments passed to 
+** sqlite3_backup_init() identify the [database connection]
+** and database name used
+** to access the source database. The values passed for the source and 
+** destination [database connection] parameters must not be the same.
+**
+** If an error occurs within sqlite3_backup_init(), then NULL is returned
+** and an error code and error message written into the [database connection] 
+** passed as the first argument. They may be retrieved using the
+** [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()] functions.
+** Otherwise, if successful, a pointer to an [sqlite3_backup] object is
+** returned. This pointer may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup 
+** operation.
+**
+** <b>sqlite3_backup_step()</b>
+**
+** Function [sqlite3_backup_step()] is used to copy up to nPage pages between 
+** the source and destination databases, where nPage is the value of the 
+** second parameter passed to sqlite3_backup_step(). If nPage is a negative
+** value, all remaining source pages are copied. If the required pages are 
+** succesfully copied, but there are still more pages to copy before the 
+** backup is complete, it returns [SQLITE_OK]. If no error occured and there 
+** are no more pages to copy, then [SQLITE_DONE] is returned. If an error 
+** occurs, then an SQLite error code is returned. As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** As well as the case where the destination database file was opened for
+** read-only access, sqlite3_backup_step() may return [SQLITE_READONLY] if
+** the destination is an in-memory database with a different page size
+** from the source database.
+**
+** If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). If the 
+** busy-handler returns non-zero before the lock is available, then 
+** [SQLITE_BUSY] is returned to the caller. In this case the call to
+** sqlite3_backup_step() can be retried later. If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then 
+** there is no point in retrying the call to sqlite3_backup_step(). These 
+** errors are considered fatal. At this point the application must accept 
+** that the backup operation has failed and pass the backup operation handle 
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** Following the first call to sqlite3_backup_step(), an exclusive lock is
+** obtained on the destination file. It is not released until either 
+** sqlite3_backup_finish() is called or the backup operation is complete 
+** and sqlite3_backup_step() returns [SQLITE_DONE]. Additionally, each time 
+** a call to sqlite3_backup_step() is made a [shared lock] is obtained on
+** the source database file. This lock is released before the
+** sqlite3_backup_step() call returns. Because the source database is not
+** locked between calls to sqlite3_backup_step(), it may be modified mid-way
+** through the backup procedure. If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be transparently
+** restarted by the next call to sqlite3_backup_step(). If the source 
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is transparently 
+** updated at the same time.
+**
+** <b>sqlite3_backup_finish()</b>
+**
+** Once sqlite3_backup_step() has returned [SQLITE_DONE], or when the 
+** application wishes to abandon the backup operation, the [sqlite3_backup]
+** object should be passed to sqlite3_backup_finish(). This releases all
+** resources associated with the backup operation. If sqlite3_backup_step()
+** has not yet returned [SQLITE_DONE], then any active write-transaction on the
+** destination database is rolled back. The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** The value returned by sqlite3_backup_finish is [SQLITE_OK] if no error
+** occurred, regardless or whether or not sqlite3_backup_step() was called
+** a sufficient number of times to complete the backup operation. Or, if
+** an out-of-memory condition or IO error occured during a call to
+** sqlite3_backup_step() then [SQLITE_NOMEM] or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] error code
+** is returned. In this case the error code and an error message are
+** written to the destination [database connection].
+**
+** A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() is
+** not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
+**
+** Each call to sqlite3_backup_step() sets two values stored internally
+** by an [sqlite3_backup] object. The number of pages still to be backed
+** up, which may be queried by sqlite3_backup_remaining(), and the total
+** number of pages in the source database file, which may be queried by
+** sqlite3_backup_pagecount().
+**
+** The values returned by these functions are only updated by
+** sqlite3_backup_step(). If the source database is modified during a backup
+** operation, then the values are not updated to account for any extra
+** pages that need to be updated or the size of the source database file
+** changing.
+**
+** <b>Concurrent Usage of Database Handles</b>
+**
+** The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination database
+** connection handle is not passed to any other API (by any thread) after 
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish(). Unfortunately SQLite does not currently check
+** for this, if the application does use the destination [database connection]
+** for some other purpose during a backup operation, things may appear to
+** work correctly but in fact be subtly malfunctioning.  Use of the
+** destination database connection while a backup is in progress might
+** also cause a mutex deadlock.
+**
+** Furthermore, if running in [shared cache mode], the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the file-system file being 
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple 
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+  sqlite3 *pDest,                        /* Destination database handle */
+  const char *zDestName,                 /* Destination database name */
+  sqlite3 *pSource,                      /* Source database handle */
+  const char *zSourceName                /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+** EXPERIMENTAL
+**
+** When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 
+** This API may be used to register a callback that SQLite will invoke 
+** when the connection currently holding the required lock relinquishes it.
+** This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back. 
+**
+** When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. After an 
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as 
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().
+**
+** If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of 
+** the other connections to use as the blocking connection.
+**
+** There may be at most one unlock-notify callback registered by a 
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old. If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is cancelled. The blocked connections 
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** <b>Callback Invocation Details</b>
+**
+** When an unlock-notify callback is registered, the application provides a 
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions 
+** related to the set of unblocked database connections.
+**
+** <b>Deadlock Detection</b>
+**
+** Assuming that after registering for an unlock-notify callback a 
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. Any
+** number of levels of indirection are allowed.
+**
+** <b>The "DROP TABLE" Exception</b>
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just 
+** SQLITE_LOCKED.
+*/
+SQLITE_API int sqlite3_unlock_notify(
+  sqlite3 *pBlocked,                          /* Waiting connection */
+  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
+  void *pNotifyArg                            /* Argument to pass to xNotify */
+);
 
 
 /*
+** CAPI3REF: String Comparison
+** EXPERIMENTAL
+**
+** The [sqlite3_strnicmp()] API allows applications and extensions to
+** compare the contents of two buffers containing UTF-8 strings in a
+** case-indendent fashion, using the same definition of case independence 
+** that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
+
+/*
 ** Undo the hack that converts floating point types to integer for
 ** builds on processors without floating point support.
 */
@@ -6050,6 +6293,7 @@ SQLITE_API int sqlite3_test_control(int op, ...);
 #endif
 #endif
 
+
 /************** End of sqlite3.h *********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
 /************** Include hash.h in the middle of sqliteInt.h ******************/
@@ -6068,7 +6312,7 @@ SQLITE_API int sqlite3_test_control(int op, ...);
 ** This is the header file for the generic hash-table implemenation
 ** used in SQLite.
 **
-** $Id: hash.h,v 1.11 2007/09/04 14:31:47 danielk1977 Exp $
+** $Id: hash.h,v 1.15 2009/05/02 13:29:38 drh Exp $
 */
 #ifndef _SQLITE_HASH_H_
 #define _SQLITE_HASH_H_
@@ -6081,19 +6325,30 @@ typedef struct HashElem HashElem;
 ** The internals of this structure are intended to be opaque -- client
 ** code should not attempt to access or modify the fields of this structure
 ** directly.  Change this structure only by using the routines below.
-** However, many of the "procedures" and "functions" for modifying and
+** However, some of the "procedures" and "functions" for modifying and
 ** accessing this structure are really macros, so we can't really make
 ** this structure opaque.
+**
+** All elements of the hash table are on a single doubly-linked list.
+** Hash.first points to the head of this list.
+**
+** There are Hash.htsize buckets.  Each bucket points to a spot in
+** the global doubly-linked list.  The contents of the bucket are the
+** element pointed to plus the next _ht.count-1 elements in the list.
+**
+** Hash.htsize and Hash.ht may be zero.  In that case lookup is done
+** by a linear search of the global list.  For small tables, the 
+** Hash.ht table is never allocated because if there are few elements
+** in the table, it is faster to do a linear search than to manage
+** the hash table.
 */
 struct Hash {
-  char keyClass;          /* SQLITE_HASH_INT, _POINTER, _STRING, _BINARY */
-  char copyKey;           /* True if copy of key made on insert */
-  int count;              /* Number of entries in this table */
-  int htsize;             /* Number of buckets in the hash table */
-  HashElem *first;        /* The first element of the array */
-  struct _ht {            /* the hash table */
-    int count;               /* Number of entries with this hash */
-    HashElem *chain;         /* Pointer to first entry with this hash */
+  unsigned int htsize;      /* Number of buckets in the hash table */
+  unsigned int count;       /* Number of entries in this table */
+  HashElem *first;          /* The first element of the array */
+  struct _ht {              /* the hash table */
+    int count;                 /* Number of entries with this hash */
+    HashElem *chain;           /* Pointer to first entry with this hash */
   } *ht;
 };
 
@@ -6104,40 +6359,17 @@ struct Hash {
 ** be opaque because it is used by macros.
 */
 struct HashElem {
-  HashElem *next, *prev;   /* Next and previous elements in the table */
-  void *data;              /* Data associated with this element */
-  void *pKey; int nKey;    /* Key associated with this element */
+  HashElem *next, *prev;       /* Next and previous elements in the table */
+  void *data;                  /* Data associated with this element */
+  const char *pKey; int nKey;  /* Key associated with this element */
 };
 
 /*
-** There are 4 different modes of operation for a hash table:
-**
-**   SQLITE_HASH_INT         nKey is used as the key and pKey is ignored.
-**
-**   SQLITE_HASH_POINTER     pKey is used as the key and nKey is ignored.
-**
-**   SQLITE_HASH_STRING      pKey points to a string that is nKey bytes long
-**                           (including the null-terminator, if any).  Case
-**                           is ignored in comparisons.
-**
-**   SQLITE_HASH_BINARY      pKey points to binary data nKey bytes long. 
-**                           memcmp() is used to compare keys.
-**
-** A copy of the key is made for SQLITE_HASH_STRING and SQLITE_HASH_BINARY
-** if the copyKey parameter to HashInit is 1.  
-*/
-/* #define SQLITE_HASH_INT       1 // NOT USED */
-/* #define SQLITE_HASH_POINTER   2 // NOT USED */
-#define SQLITE_HASH_STRING    3
-#define SQLITE_HASH_BINARY    4
-
-/*
 ** Access routines.  To delete, insert a NULL pointer.
 */
-SQLITE_PRIVATE void sqlite3HashInit(Hash*, int keytype, int copyKey);
-SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const void *pKey, int nKey, void *pData);
-SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const void *pKey, int nKey);
-SQLITE_PRIVATE HashElem *sqlite3HashFindElem(const Hash*, const void *pKey, int nKey);
+SQLITE_PRIVATE void sqlite3HashInit(Hash*);
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const char *pKey, int nKey, void *pData);
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const char *pKey, int nKey);
 SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 
 /*
@@ -6155,13 +6387,13 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #define sqliteHashFirst(H)  ((H)->first)
 #define sqliteHashNext(E)   ((E)->next)
 #define sqliteHashData(E)   ((E)->data)
-#define sqliteHashKey(E)    ((E)->pKey)
-#define sqliteHashKeysize(E) ((E)->nKey)
+/* #define sqliteHashKey(E)    ((E)->pKey) // NOT USED */
+/* #define sqliteHashKeysize(E) ((E)->nKey)  // NOT USED */
 
 /*
 ** Number of entries in a hash table
 */
-#define sqliteHashCount(H)  ((H)->count)
+/* #define sqliteHashCount(H)  ((H)->count) // NOT USED */
 
 #endif /* _SQLITE_HASH_H_ */
 
@@ -6181,146 +6413,151 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #define TK_COMMIT                         10
 #define TK_END                            11
 #define TK_ROLLBACK                       12
-#define TK_CREATE                         13
-#define TK_TABLE                          14
-#define TK_IF                             15
-#define TK_NOT                            16
-#define TK_EXISTS                         17
-#define TK_TEMP                           18
-#define TK_LP                             19
-#define TK_RP                             20
-#define TK_AS                             21
-#define TK_COMMA                          22
-#define TK_ID                             23
-#define TK_ABORT                          24
-#define TK_AFTER                          25
-#define TK_ANALYZE                        26
-#define TK_ASC                            27
-#define TK_ATTACH                         28
-#define TK_BEFORE                         29
-#define TK_CASCADE                        30
-#define TK_CAST                           31
-#define TK_CONFLICT                       32
-#define TK_DATABASE                       33
-#define TK_DESC                           34
-#define TK_DETACH                         35
-#define TK_EACH                           36
-#define TK_FAIL                           37
-#define TK_FOR                            38
-#define TK_IGNORE                         39
-#define TK_INITIALLY                      40
-#define TK_INSTEAD                        41
-#define TK_LIKE_KW                        42
-#define TK_MATCH                          43
-#define TK_KEY                            44
-#define TK_OF                             45
-#define TK_OFFSET                         46
-#define TK_PRAGMA                         47
-#define TK_RAISE                          48
-#define TK_REPLACE                        49
-#define TK_RESTRICT                       50
-#define TK_ROW                            51
-#define TK_TRIGGER                        52
-#define TK_VACUUM                         53
-#define TK_VIEW                           54
-#define TK_VIRTUAL                        55
-#define TK_REINDEX                        56
-#define TK_RENAME                         57
-#define TK_CTIME_KW                       58
-#define TK_ANY                            59
-#define TK_OR                             60
-#define TK_AND                            61
-#define TK_IS                             62
-#define TK_BETWEEN                        63
-#define TK_IN                             64
-#define TK_ISNULL                         65
-#define TK_NOTNULL                        66
-#define TK_NE                             67
-#define TK_EQ                             68
-#define TK_GT                             69
-#define TK_LE                             70
-#define TK_LT                             71
-#define TK_GE                             72
-#define TK_ESCAPE                         73
-#define TK_BITAND                         74
-#define TK_BITOR                          75
-#define TK_LSHIFT                         76
-#define TK_RSHIFT                         77
-#define TK_PLUS                           78
-#define TK_MINUS                          79
-#define TK_STAR                           80
-#define TK_SLASH                          81
-#define TK_REM                            82
-#define TK_CONCAT                         83
-#define TK_COLLATE                        84
-#define TK_UMINUS                         85
-#define TK_UPLUS                          86
-#define TK_BITNOT                         87
-#define TK_STRING                         88
-#define TK_JOIN_KW                        89
-#define TK_CONSTRAINT                     90
-#define TK_DEFAULT                        91
-#define TK_NULL                           92
-#define TK_PRIMARY                        93
-#define TK_UNIQUE                         94
-#define TK_CHECK                          95
-#define TK_REFERENCES                     96
-#define TK_AUTOINCR                       97
-#define TK_ON                             98
-#define TK_DELETE                         99
-#define TK_UPDATE                         100
-#define TK_INSERT                         101
-#define TK_SET                            102
-#define TK_DEFERRABLE                     103
-#define TK_FOREIGN                        104
-#define TK_DROP                           105
-#define TK_UNION                          106
-#define TK_ALL                            107
-#define TK_EXCEPT                         108
-#define TK_INTERSECT                      109
-#define TK_SELECT                         110
-#define TK_DISTINCT                       111
-#define TK_DOT                            112
-#define TK_FROM                           113
-#define TK_JOIN                           114
-#define TK_USING                          115
-#define TK_ORDER                          116
-#define TK_BY                             117
-#define TK_GROUP                          118
-#define TK_HAVING                         119
-#define TK_LIMIT                          120
-#define TK_WHERE                          121
-#define TK_INTO                           122
-#define TK_VALUES                         123
-#define TK_INTEGER                        124
-#define TK_FLOAT                          125
-#define TK_BLOB                           126
-#define TK_REGISTER                       127
-#define TK_VARIABLE                       128
-#define TK_CASE                           129
-#define TK_WHEN                           130
-#define TK_THEN                           131
-#define TK_ELSE                           132
-#define TK_INDEX                          133
-#define TK_ALTER                          134
-#define TK_TO                             135
-#define TK_ADD                            136
-#define TK_COLUMNKW                       137
-#define TK_TO_TEXT                        138
-#define TK_TO_BLOB                        139
-#define TK_TO_NUMERIC                     140
-#define TK_TO_INT                         141
-#define TK_TO_REAL                        142
-#define TK_END_OF_FILE                    143
-#define TK_ILLEGAL                        144
-#define TK_SPACE                          145
-#define TK_UNCLOSED_STRING                146
-#define TK_COMMENT                        147
-#define TK_FUNCTION                       148
-#define TK_COLUMN                         149
-#define TK_AGG_FUNCTION                   150
-#define TK_AGG_COLUMN                     151
-#define TK_CONST_FUNC                     152
+#define TK_SAVEPOINT                      13
+#define TK_RELEASE                        14
+#define TK_TO                             15
+#define TK_TABLE                          16
+#define TK_CREATE                         17
+#define TK_IF                             18
+#define TK_NOT                            19
+#define TK_EXISTS                         20
+#define TK_TEMP                           21
+#define TK_LP                             22
+#define TK_RP                             23
+#define TK_AS                             24
+#define TK_COMMA                          25
+#define TK_ID                             26
+#define TK_INDEXED                        27
+#define TK_ABORT                          28
+#define TK_ACTION                         29
+#define TK_AFTER                          30
+#define TK_ANALYZE                        31
+#define TK_ASC                            32
+#define TK_ATTACH                         33
+#define TK_BEFORE                         34
+#define TK_BY                             35
+#define TK_CASCADE                        36
+#define TK_CAST                           37
+#define TK_COLUMNKW                       38
+#define TK_CONFLICT                       39
+#define TK_DATABASE                       40
+#define TK_DESC                           41
+#define TK_DETACH                         42
+#define TK_EACH                           43
+#define TK_FAIL                           44
+#define TK_FOR                            45
+#define TK_IGNORE                         46
+#define TK_INITIALLY                      47
+#define TK_INSTEAD                        48
+#define TK_LIKE_KW                        49
+#define TK_MATCH                          50
+#define TK_NO                             51
+#define TK_KEY                            52
+#define TK_OF                             53
+#define TK_OFFSET                         54
+#define TK_PRAGMA                         55
+#define TK_RAISE                          56
+#define TK_REPLACE                        57
+#define TK_RESTRICT                       58
+#define TK_ROW                            59
+#define TK_TRIGGER                        60
+#define TK_VACUUM                         61
+#define TK_VIEW                           62
+#define TK_VIRTUAL                        63
+#define TK_REINDEX                        64
+#define TK_RENAME                         65
+#define TK_CTIME_KW                       66
+#define TK_ANY                            67
+#define TK_OR                             68
+#define TK_AND                            69
+#define TK_IS                             70
+#define TK_BETWEEN                        71
+#define TK_IN                             72
+#define TK_ISNULL                         73
+#define TK_NOTNULL                        74
+#define TK_NE                             75
+#define TK_EQ                             76
+#define TK_GT                             77
+#define TK_LE                             78
+#define TK_LT                             79
+#define TK_GE                             80
+#define TK_ESCAPE                         81
+#define TK_BITAND                         82
+#define TK_BITOR                          83
+#define TK_LSHIFT                         84
+#define TK_RSHIFT                         85
+#define TK_PLUS                           86
+#define TK_MINUS                          87
+#define TK_STAR                           88
+#define TK_SLASH                          89
+#define TK_REM                            90
+#define TK_CONCAT                         91
+#define TK_COLLATE                        92
+#define TK_BITNOT                         93
+#define TK_STRING                         94
+#define TK_JOIN_KW                        95
+#define TK_CONSTRAINT                     96
+#define TK_DEFAULT                        97
+#define TK_NULL                           98
+#define TK_PRIMARY                        99
+#define TK_UNIQUE                         100
+#define TK_CHECK                          101
+#define TK_REFERENCES                     102
+#define TK_AUTOINCR                       103
+#define TK_ON                             104
+#define TK_DELETE                         105
+#define TK_UPDATE                         106
+#define TK_SET                            107
+#define TK_DEFERRABLE                     108
+#define TK_FOREIGN                        109
+#define TK_DROP                           110
+#define TK_UNION                          111
+#define TK_ALL                            112
+#define TK_EXCEPT                         113
+#define TK_INTERSECT                      114
+#define TK_SELECT                         115
+#define TK_DISTINCT                       116
+#define TK_DOT                            117
+#define TK_FROM                           118
+#define TK_JOIN                           119
+#define TK_USING                          120
+#define TK_ORDER                          121
+#define TK_GROUP                          122
+#define TK_HAVING                         123
+#define TK_LIMIT                          124
+#define TK_WHERE                          125
+#define TK_INTO                           126
+#define TK_VALUES                         127
+#define TK_INSERT                         128
+#define TK_INTEGER                        129
+#define TK_FLOAT                          130
+#define TK_BLOB                           131
+#define TK_REGISTER                       132
+#define TK_VARIABLE                       133
+#define TK_CASE                           134
+#define TK_WHEN                           135
+#define TK_THEN                           136
+#define TK_ELSE                           137
+#define TK_INDEX                          138
+#define TK_ALTER                          139
+#define TK_ADD                            140
+#define TK_TO_TEXT                        141
+#define TK_TO_BLOB                        142
+#define TK_TO_NUMERIC                     143
+#define TK_TO_INT                         144
+#define TK_TO_REAL                        145
+#define TK_ISNOT                          146
+#define TK_END_OF_FILE                    147
+#define TK_ILLEGAL                        148
+#define TK_SPACE                          149
+#define TK_UNCLOSED_STRING                150
+#define TK_FUNCTION                       151
+#define TK_COLUMN                         152
+#define TK_AGG_FUNCTION                   153
+#define TK_AGG_COLUMN                     154
+#define TK_CONST_FUNC                     155
+#define TK_UMINUS                         156
+#define TK_UPLUS                          157
 
 /************** End of parse.h ***********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
@@ -6338,11 +6575,12 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 # define double sqlite_int64
 # define LONGDOUBLE_TYPE sqlite_int64
 # ifndef SQLITE_BIG_DBL
-#   define SQLITE_BIG_DBL (0x7fffffffffffffff)
+#   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
 # endif
 # define SQLITE_OMIT_DATETIME_FUNCS 1
 # define SQLITE_OMIT_TRACE 1
 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
+# undef SQLITE_HAVE_ISNAN
 #endif
 #ifndef SQLITE_BIG_DBL
 # define SQLITE_BIG_DBL (1e99)
@@ -6384,12 +6622,16 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 # define SQLITE_DEFAULT_FILE_FORMAT 1
 #endif
 
+#ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
+# define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
+#endif
+
 /*
-** Provide a default value for TEMP_STORE in case it is not specified
+** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
 ** on the command-line
 */
-#ifndef TEMP_STORE
-# define TEMP_STORE 1
+#ifndef SQLITE_TEMP_STORE
+# define SQLITE_TEMP_STORE 1
 #endif
 
 /*
@@ -6461,18 +6703,27 @@ typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
 typedef INT16_TYPE i16;            /* 2-byte signed integer */
 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
-typedef UINT8_TYPE i8;             /* 1-byte signed integer */
+typedef INT8_TYPE i8;              /* 1-byte signed integer */
+
+/*
+** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
+** that can be stored in a u32 without loss of data.  The value
+** is 0x00000000ffffffff.  But because of quirks of some compilers, we
+** have to specify the value in the less intuitive manner shown:
+*/
+#define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
 
 /*
 ** Macros to determine whether the machine is big or little endian,
 ** evaluated at runtime.
 */
 #ifdef SQLITE_AMALGAMATION
-SQLITE_PRIVATE const int sqlite3one;
+SQLITE_PRIVATE const int sqlite3one = 1;
 #else
 SQLITE_PRIVATE const int sqlite3one;
 #endif
-#if defined(i386) || defined(__i386__) || defined(_M_IX86)
+#if defined(i386) || defined(__i386__) || defined(_M_IX86)\
+                             || defined(__x86_64) || defined(__x86_64__)
 # define SQLITE_BIGENDIAN    0
 # define SQLITE_LITTLEENDIAN 1
 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
@@ -6490,6 +6741,23 @@ SQLITE_PRIVATE const int sqlite3one;
 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
 
+/* 
+** Round up a number to the next larger multiple of 8.  This is used
+** to force 8-byte alignment on 64-bit architectures.
+*/
+#define ROUND8(x)     (((x)+7)&~7)
+
+/*
+** Round down to the nearest multiple of 8
+*/
+#define ROUNDDOWN8(x) ((x)&~7)
+
+/*
+** Assert that the pointer X is aligned to an 8-byte boundary.
+*/
+#define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
+
+
 /*
 ** An instance of the following structure is used to store the busy-handler
 ** callback for a given sqlite handle. 
@@ -6528,38 +6796,101 @@ struct BusyHandler {
 ** A convenience macro that returns the number of elements in
 ** an array.
 */
-#define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
+#define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
+
+/*
+** The following value as a destructor means to use sqlite3DbFree().
+** This is an internal extension to SQLITE_STATIC and SQLITE_TRANSIENT.
+*/
+#define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3DbFree)
+
+/*
+** When SQLITE_OMIT_WSD is defined, it means that the target platform does
+** not support Writable Static Data (WSD) such as global and static variables.
+** All variables must either be on the stack or dynamically allocated from
+** the heap.  When WSD is unsupported, the variable declarations scattered
+** throughout the SQLite code must become constants instead.  The SQLITE_WSD
+** macro is used for this purpose.  And instead of referencing the variable
+** directly, we use its constant as a key to lookup the run-time allocated
+** buffer that holds real variable.  The constant is also the initializer
+** for the run-time allocated buffer.
+**
+** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
+** macros become no-ops and have zero performance impact.
+*/
+#ifdef SQLITE_OMIT_WSD
+  #define SQLITE_WSD const
+  #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
+  #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
+SQLITE_API   int sqlite3_wsd_init(int N, int J);
+SQLITE_API   void *sqlite3_wsd_find(void *K, int L);
+#else
+  #define SQLITE_WSD 
+  #define GLOBAL(t,v) v
+  #define sqlite3GlobalConfig sqlite3Config
+#endif
+
+/*
+** The following macros are used to suppress compiler warnings and to
+** make it clear to human readers when a function parameter is deliberately 
+** left unused within the body of a function. This usually happens when
+** a function is called via a function pointer. For example the 
+** implementation of an SQL aggregate step callback may not use the
+** parameter indicating the number of arguments passed to the aggregate,
+** if it knows that this is enforced elsewhere.
+**
+** When a function parameter is not used at all within the body of a function,
+** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
+** However, these macros may also be used to suppress warnings related to
+** parameters that may or may not be used depending on compilation options.
+** For example those parameters only used in assert() statements. In these
+** cases the parameters are named as per the usual conventions.
+*/
+#define UNUSED_PARAMETER(x) (void)(x)
+#define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
 
 /*
 ** Forward references to structures
 */
 typedef struct AggInfo AggInfo;
 typedef struct AuthContext AuthContext;
+typedef struct AutoincInfo AutoincInfo;
 typedef struct Bitvec Bitvec;
+typedef struct RowSet RowSet;
 typedef struct CollSeq CollSeq;
 typedef struct Column Column;
 typedef struct Db Db;
 typedef struct Schema Schema;
 typedef struct Expr Expr;
 typedef struct ExprList ExprList;
+typedef struct ExprSpan ExprSpan;
 typedef struct FKey FKey;
 typedef struct FuncDef FuncDef;
+typedef struct FuncDefHash FuncDefHash;
 typedef struct IdList IdList;
 typedef struct Index Index;
+typedef struct IndexSample IndexSample;
 typedef struct KeyClass KeyClass;
 typedef struct KeyInfo KeyInfo;
+typedef struct Lookaside Lookaside;
+typedef struct LookasideSlot LookasideSlot;
 typedef struct Module Module;
 typedef struct NameContext NameContext;
 typedef struct Parse Parse;
+typedef struct Savepoint Savepoint;
 typedef struct Select Select;
 typedef struct SrcList SrcList;
 typedef struct StrAccum StrAccum;
 typedef struct Table Table;
 typedef struct TableLock TableLock;
 typedef struct Token Token;
-typedef struct TriggerStack TriggerStack;
+typedef struct TriggerPrg TriggerPrg;
 typedef struct TriggerStep TriggerStep;
 typedef struct Trigger Trigger;
+typedef struct UnpackedRecord UnpackedRecord;
+typedef struct VTable VTable;
+typedef struct Walker Walker;
+typedef struct WherePlan WherePlan;
 typedef struct WhereInfo WhereInfo;
 typedef struct WhereLevel WhereLevel;
 
@@ -6585,7 +6916,7 @@ typedef struct WhereLevel WhereLevel;
 ** subsystem.  See comments in the source code for a detailed description
 ** of what each interface routine does.
 **
-** @(#) $Id: btree.h,v 1.98 2008/04/26 13:39:47 drh Exp $
+** @(#) $Id: btree.h,v 1.120 2009/07/22 00:35:24 drh Exp $
 */
 #ifndef _BTREE_H_
 #define _BTREE_H_
@@ -6630,7 +6961,7 @@ struct BtreeMutexArray {
 SQLITE_PRIVATE int sqlite3BtreeOpen(
   const char *zFilename,   /* Name of database file to open */
   sqlite3 *db,             /* Associated database connection */
-  Btree **,                /* Return open Btree* here */
+  Btree **ppBtree,         /* Return open Btree* here */
   int flags,               /* Flags */
   int vfsFlags             /* Flags passed through to VFS open */
 );
@@ -6648,16 +6979,11 @@ SQLITE_PRIVATE int sqlite3BtreeOpen(
 #define BTREE_READWRITE    16  /* Open for both reading and writing */
 #define BTREE_CREATE       32  /* Create the database if it does not exist */
 
-/* Additional values for the 4th argument of sqlite3BtreeOpen that
-** are not associated with PAGER_ values.
-*/
-#define BTREE_PRIVATE      64  /* Never share with other connections */
-
 SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
 SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree*,int,int);
 SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
-SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree*,int,int);
+SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
 SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
 SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree*);
@@ -6668,19 +6994,17 @@ SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
 SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeCommit(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeRollback(Btree*);
-SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*);
-SQLITE_PRIVATE int sqlite3BtreeCommitStmt(Btree*);
-SQLITE_PRIVATE int sqlite3BtreeRollbackStmt(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*,int);
 SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree*, int*, int flags);
 SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree*);
-SQLITE_PRIVATE int sqlite3BtreeIsInStmt(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeIsInBackup(Btree*);
 SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
-SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *);
-SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *, int, u8);
+SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *pBtree);
+SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
+SQLITE_PRIVATE int sqlite3BtreeSavepoint(Btree *, int, int);
 
 SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *);
-SQLITE_PRIVATE const char *sqlite3BtreeGetDirname(Btree *);
 SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *);
 SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *, Btree *);
 
@@ -6694,12 +7018,32 @@ SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
 #define BTREE_LEAFDATA   4    /* Data stored in leaves only.  Implies INTKEY */
 
 SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
-SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int);
-SQLITE_PRIVATE int sqlite3BtreeGetMeta(Btree*, int idx, u32 *pValue);
-SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
+SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
 SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree*, int);
 
-struct UnpackedRecord;  /* Forward declaration.  Definition in vdbeaux.c. */
+SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
+SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
+
+/*
+** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
+** should be one of the following values. The integer values are assigned 
+** to constants so that the offset of the corresponding field in an
+** SQLite database header may be found using the following formula:
+**
+**   offset = 36 + (idx * 4)
+**
+** For example, the free-page-count field is located at byte offset 36 of
+** the database file header. The incr-vacuum-flag field is located at
+** byte offset 64 (== 36+4*7).
+*/
+#define BTREE_FREE_PAGE_COUNT     0
+#define BTREE_SCHEMA_VERSION      1
+#define BTREE_FILE_FORMAT         2
+#define BTREE_DEFAULT_CACHE_SIZE  3
+#define BTREE_LARGEST_ROOT_PAGE   4
+#define BTREE_TEXT_ENCODING       5
+#define BTREE_USER_VERSION        6
+#define BTREE_INCR_VACUUM         7
 
 SQLITE_PRIVATE int sqlite3BtreeCursor(
   Btree*,                              /* BTree containing table to open */
@@ -6711,42 +7055,50 @@ SQLITE_PRIVATE int sqlite3BtreeCursor(
 SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
 
 SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
-SQLITE_PRIVATE int sqlite3BtreeMoveto(
+SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
   BtCursor*,
-  const void *pKey,
-  struct UnpackedRecord *pUnKey,
-  i64 nKey,
+  UnpackedRecord *pUnKey,
+  i64 intKey,
   int bias,
   int *pRes
 );
+SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
 SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*);
 SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
                                   const void *pData, int nData,
-                                  int nZero, int bias);
+                                  int nZero, int bias, int seekResult);
 SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
 SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
 SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int *pRes);
 SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
-SQLITE_PRIVATE int sqlite3BtreeFlags(BtCursor*);
 SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
 SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
 SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
-SQLITE_PRIVATE sqlite3 *sqlite3BtreeCursorDb(const BtCursor*);
 SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor*, int *pAmt);
 SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor*, int *pAmt);
 SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
 SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE void sqlite3BtreeSetCachedRowid(BtCursor*, sqlite3_int64);
+SQLITE_PRIVATE sqlite3_int64 sqlite3BtreeGetCachedRowid(BtCursor*);
 
 SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
 SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
 
 SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
 SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
+SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
+
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
+#endif
+
+#ifndef SQLITE_OMIT_BTREECOUNT
+SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *, i64 *);
+#endif
 
 #ifdef SQLITE_TEST
 SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
 SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
-SQLITE_PRIVATE int sqlite3BtreePageDump(Btree*, int, int recursive);
 #endif
 
 /*
@@ -6754,30 +7106,39 @@ SQLITE_PRIVATE int sqlite3BtreePageDump(Btree*, int, int recursive);
 ** use mutexes to access the BtShared structures.  So make the
 ** Enter and Leave procedures no-ops.
 */
-#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
+#ifndef SQLITE_OMIT_SHARED_CACHE
 SQLITE_PRIVATE   void sqlite3BtreeEnter(Btree*);
+SQLITE_PRIVATE   void sqlite3BtreeEnterAll(sqlite3*);
+#else
+# define sqlite3BtreeEnter(X) 
+# define sqlite3BtreeEnterAll(X)
+#endif
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
 SQLITE_PRIVATE   void sqlite3BtreeLeave(Btree*);
-SQLITE_PRIVATE   int sqlite3BtreeHoldsMutex(Btree*);
 SQLITE_PRIVATE   void sqlite3BtreeEnterCursor(BtCursor*);
 SQLITE_PRIVATE   void sqlite3BtreeLeaveCursor(BtCursor*);
-SQLITE_PRIVATE   void sqlite3BtreeEnterAll(sqlite3*);
 SQLITE_PRIVATE   void sqlite3BtreeLeaveAll(sqlite3*);
-SQLITE_PRIVATE   int sqlite3BtreeHoldsAllMutexes(sqlite3*);
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayEnter(BtreeMutexArray*);
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayLeave(BtreeMutexArray*);
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayInsert(BtreeMutexArray*, Btree*);
+#ifndef NDEBUG
+  /* These routines are used inside assert() statements only. */
+SQLITE_PRIVATE   int sqlite3BtreeHoldsMutex(Btree*);
+SQLITE_PRIVATE   int sqlite3BtreeHoldsAllMutexes(sqlite3*);
+#endif
 #else
-# define sqlite3BtreeEnter(X)
+
 # define sqlite3BtreeLeave(X)
-# define sqlite3BtreeHoldsMutex(X) 1
 # define sqlite3BtreeEnterCursor(X)
 # define sqlite3BtreeLeaveCursor(X)
-# define sqlite3BtreeEnterAll(X)
 # define sqlite3BtreeLeaveAll(X)
-# define sqlite3BtreeHoldsAllMutexes(X) 1
 # define sqlite3BtreeMutexArrayEnter(X)
 # define sqlite3BtreeMutexArrayLeave(X)
 # define sqlite3BtreeMutexArrayInsert(X,Y)
+
+# define sqlite3BtreeHoldsMutex(X) 1
+# define sqlite3BtreeHoldsAllMutexes(X) 1
 #endif
 
 
@@ -6804,7 +7165,7 @@ SQLITE_PRIVATE   void sqlite3BtreeMutexArrayInsert(BtreeMutexArray*, Btree*);
 ** or VDBE.  The VDBE implements an abstract machine that runs a
 ** simple program to access and modify the underlying database.
 **
-** $Id: vdbe.h,v 1.131 2008/05/01 17:03:49 drh Exp $
+** $Id: vdbe.h,v 1.142 2009/07/24 17:58:53 danielk1977 Exp $
 */
 #ifndef _SQLITE_VDBE_H_
 #define _SQLITE_VDBE_H_
@@ -6822,7 +7183,7 @@ typedef struct Vdbe Vdbe;
 */
 typedef struct VdbeFunc VdbeFunc;
 typedef struct Mem Mem;
-typedef struct UnpackedRecord UnpackedRecord;
+typedef struct SubProgram SubProgram;
 
 /*
 ** A single instruction of the virtual machine has an opcode
@@ -6837,7 +7198,7 @@ struct VdbeOp {
   int p1;             /* First operand */
   int p2;             /* Second parameter (often the jump destination) */
   int p3;             /* The third parameter */
-  union {             /* forth parameter */
+  union {             /* fourth parameter */
     int i;                 /* Integer value if p4type==P4_INT32 */
     void *p;               /* Generic pointer */
     char *z;               /* Pointer to data for string (char array) types */
@@ -6847,19 +7208,34 @@ struct VdbeOp {
     VdbeFunc *pVdbeFunc;   /* Used when p4type is P4_VDBEFUNC */
     CollSeq *pColl;        /* Used when p4type is P4_COLLSEQ */
     Mem *pMem;             /* Used when p4type is P4_MEM */
-    sqlite3_vtab *pVtab;   /* Used when p4type is P4_VTAB */
+    VTable *pVtab;         /* Used when p4type is P4_VTAB */
     KeyInfo *pKeyInfo;     /* Used when p4type is P4_KEYINFO */
+    int *ai;               /* Used when p4type is P4_INTARRAY */
+    SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
   } p4;
 #ifdef SQLITE_DEBUG
-  char *zComment;     /* Comment to improve readability */
+  char *zComment;          /* Comment to improve readability */
 #endif
 #ifdef VDBE_PROFILE
-  int cnt;            /* Number of times this instruction was executed */
-  long long cycles;   /* Total time spend executing this instruction */
+  int cnt;                 /* Number of times this instruction was executed */
+  u64 cycles;              /* Total time spent executing this instruction */
 #endif
 };
 typedef struct VdbeOp VdbeOp;
 
+
+/*
+** A sub-routine used to implement a trigger program.
+*/
+struct SubProgram {
+  VdbeOp *aOp;                  /* Array of opcodes for sub-program */
+  int nOp;                      /* Elements in aOp[] */
+  int nMem;                     /* Number of memory cells required */
+  int nCsr;                     /* Number of cursors required */
+  int nRef;                     /* Number of pointers to this structure */
+  void *token;                  /* id that may be used to recursive triggers */
+};
+
 /*
 ** A smaller version of VdbeOp used for the VdbeAddOpList() function because
 ** it takes up less space.
@@ -6873,7 +7249,7 @@ struct VdbeOpList {
 typedef struct VdbeOpList VdbeOpList;
 
 /*
-** Allowed values of VdbeOp.p3type
+** Allowed values of VdbeOp.p4type
 */
 #define P4_NOTUSED    0   /* The P4 parameter is not used */
 #define P4_DYNAMIC  (-1)  /* Pointer to a string obtained from sqliteMalloc() */
@@ -6889,6 +7265,8 @@ typedef struct VdbeOpList VdbeOpList;
 #define P4_REAL     (-12) /* P4 is a 64-bit floating point value */
 #define P4_INT64    (-13) /* P4 is a 64-bit signed integer */
 #define P4_INT32    (-14) /* P4 is a 32-bit signed integer */
+#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
+#define P4_SUBPROGRAM  (-18) /* P4 is a pointer to a SubProgram structure */
 
 /* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
 ** is made.  That copy is freed when the Vdbe is finalized.  But if the
@@ -6897,7 +7275,8 @@ typedef struct VdbeOpList VdbeOpList;
 ** from a single sqliteMalloc().  But no copy is made and the calling
 ** function should *not* try to free the KeyInfo.
 */
-#define P4_KEYINFO_HANDOFF (-9)
+#define P4_KEYINFO_HANDOFF (-16)
+#define P4_KEYINFO_STATIC  (-17)
 
 /*
 ** The Vdbe.aColName array contains 5n Mem structures, where n is the 
@@ -6938,146 +7317,149 @@ typedef struct VdbeOpList VdbeOpList;
 #define OP_Affinity                             2
 #define OP_Column                               3
 #define OP_SetCookie                            4
-#define OP_Real                               125   /* same as TK_FLOAT    */
-#define OP_Sequence                             5
-#define OP_MoveGt                               6
-#define OP_Ge                                  72   /* same as TK_GE       */
-#define OP_RowKey                               7
-#define OP_SCopy                                8
-#define OP_Eq                                  68   /* same as TK_EQ       */
-#define OP_OpenWrite                            9
-#define OP_NotNull                             66   /* same as TK_NOTNULL  */
-#define OP_If                                  10
-#define OP_ToInt                              141   /* same as TK_TO_INT   */
-#define OP_String8                             88   /* same as TK_STRING   */
-#define OP_VRowid                              11
+#define OP_Seek                                 5
+#define OP_Real                               130   /* same as TK_FLOAT    */
+#define OP_Sequence                             6
+#define OP_Savepoint                            7
+#define OP_Ge                                  80   /* same as TK_GE       */
+#define OP_RowKey                               8
+#define OP_SCopy                                9
+#define OP_Eq                                  76   /* same as TK_EQ       */
+#define OP_OpenWrite                           10
+#define OP_NotNull                             74   /* same as TK_NOTNULL  */
+#define OP_If                                  11
+#define OP_ToInt                              144   /* same as TK_TO_INT   */
+#define OP_String8                             94   /* same as TK_STRING   */
 #define OP_CollSeq                             12
 #define OP_OpenRead                            13
 #define OP_Expire                              14
 #define OP_AutoCommit                          15
-#define OP_Gt                                  69   /* same as TK_GT       */
+#define OP_Gt                                  77   /* same as TK_GT       */
+#define OP_Pagecount                           16
 #define OP_IntegrityCk                         17
 #define OP_Sort                                18
-#define OP_Copy                                19
-#define OP_Trace                               20
-#define OP_Function                            21
-#define OP_IfNeg                               22
-#define OP_And                                 61   /* same as TK_AND      */
-#define OP_Subtract                            79   /* same as TK_MINUS    */
-#define OP_Noop                                23
-#define OP_Return                              24
-#define OP_Remainder                           82   /* same as TK_REM      */
-#define OP_NewRowid                            25
-#define OP_Multiply                            80   /* same as TK_STAR     */
-#define OP_Variable                            26
-#define OP_String                              27
-#define OP_RealAffinity                        28
-#define OP_VRename                             29
-#define OP_ParseSchema                         30
-#define OP_VOpen                               31
-#define OP_Close                               32
-#define OP_CreateIndex                         33
-#define OP_IsUnique                            34
-#define OP_NotFound                            35
-#define OP_Int64                               36
-#define OP_MustBeInt                           37
-#define OP_Halt                                38
-#define OP_Rowid                               39
-#define OP_IdxLT                               40
-#define OP_AddImm                              41
-#define OP_Statement                           42
-#define OP_RowData                             43
-#define OP_MemMax                              44
-#define OP_Or                                  60   /* same as TK_OR       */
-#define OP_NotExists                           45
-#define OP_Gosub                               46
-#define OP_Divide                              81   /* same as TK_SLASH    */
-#define OP_Integer                             47
-#define OP_ToNumeric                          140   /* same as TK_TO_NUMERIC*/
-#define OP_Prev                                48
-#define OP_Concat                              83   /* same as TK_CONCAT   */
-#define OP_BitAnd                              74   /* same as TK_BITAND   */
-#define OP_VColumn                             49
-#define OP_CreateTable                         50
-#define OP_Last                                51
-#define OP_IsNull                              65   /* same as TK_ISNULL   */
-#define OP_IncrVacuum                          52
-#define OP_IdxRowid                            53
-#define OP_ShiftRight                          77   /* same as TK_RSHIFT   */
-#define OP_ResetCount                          54
-#define OP_FifoWrite                           55
-#define OP_ContextPush                         56
-#define OP_DropTrigger                         57
-#define OP_DropIndex                           58
-#define OP_IdxGE                               59
-#define OP_IdxDelete                           62
-#define OP_Vacuum                              63
-#define OP_MoveLe                              64
-#define OP_IfNot                               73
-#define OP_DropTable                           84
-#define OP_MakeRecord                          85
-#define OP_ToBlob                             139   /* same as TK_TO_BLOB  */
-#define OP_ResultRow                           86
-#define OP_Delete                              89
-#define OP_AggFinal                            90
-#define OP_ShiftLeft                           76   /* same as TK_LSHIFT   */
-#define OP_Goto                                91
-#define OP_TableLock                           92
-#define OP_FifoRead                            93
-#define OP_Clear                               94
-#define OP_MoveLt                              95
-#define OP_Le                                  70   /* same as TK_LE       */
-#define OP_VerifyCookie                        96
-#define OP_AggStep                             97
-#define OP_ToText                             138   /* same as TK_TO_TEXT  */
-#define OP_Not                                 16   /* same as TK_NOT      */
-#define OP_ToReal                             142   /* same as TK_TO_REAL  */
-#define OP_SetNumColumns                       98
-#define OP_Transaction                         99
-#define OP_VFilter                            100
-#define OP_Ne                                  67   /* same as TK_NE       */
-#define OP_VDestroy                           101
-#define OP_ContextPop                         102
-#define OP_BitOr                               75   /* same as TK_BITOR    */
-#define OP_Next                               103
-#define OP_IdxInsert                          104
-#define OP_Lt                                  71   /* same as TK_LT       */
-#define OP_Insert                             105
-#define OP_Destroy                            106
-#define OP_ReadCookie                         107
-#define OP_ForceInt                           108
-#define OP_LoadAnalysis                       109
-#define OP_Explain                            110
-#define OP_OpenPseudo                         111
-#define OP_OpenEphemeral                      112
-#define OP_Null                               113
-#define OP_Move                               114
-#define OP_Blob                               115
-#define OP_Add                                 78   /* same as TK_PLUS     */
-#define OP_Rewind                             116
-#define OP_MoveGe                             117
-#define OP_VBegin                             118
-#define OP_VUpdate                            119
-#define OP_IfZero                             120
-#define OP_BitNot                              87   /* same as TK_BITNOT   */
-#define OP_VCreate                            121
-#define OP_Found                              122
-#define OP_IfPos                              123
-#define OP_NullRow                            124
+#define OP_Copy                                20
+#define OP_Trace                               21
+#define OP_Function                            22
+#define OP_IfNeg                               23
+#define OP_And                                 69   /* same as TK_AND      */
+#define OP_Subtract                            87   /* same as TK_MINUS    */
+#define OP_Noop                                24
+#define OP_Program                             25
+#define OP_Return                              26
+#define OP_Remainder                           90   /* same as TK_REM      */
+#define OP_NewRowid                            27
+#define OP_Multiply                            88   /* same as TK_STAR     */
+#define OP_FkCounter                           28
+#define OP_Variable                            29
+#define OP_String                              30
+#define OP_RealAffinity                        31
+#define OP_VRename                             32
+#define OP_ParseSchema                         33
+#define OP_VOpen                               34
+#define OP_Close                               35
+#define OP_CreateIndex                         36
+#define OP_IsUnique                            37
+#define OP_NotFound                            38
+#define OP_Int64                               39
+#define OP_MustBeInt                           40
+#define OP_Halt                                41
+#define OP_Rowid                               42
+#define OP_IdxLT                               43
+#define OP_AddImm                              44
+#define OP_RowData                             45
+#define OP_MemMax                              46
+#define OP_Or                                  68   /* same as TK_OR       */
+#define OP_NotExists                           47
+#define OP_Gosub                               48
+#define OP_Divide                              89   /* same as TK_SLASH    */
+#define OP_Integer                             49
+#define OP_ToNumeric                          143   /* same as TK_TO_NUMERIC*/
+#define OP_Prev                                50
+#define OP_RowSetRead                          51
+#define OP_Concat                              91   /* same as TK_CONCAT   */
+#define OP_RowSetAdd                           52
+#define OP_BitAnd                              82   /* same as TK_BITAND   */
+#define OP_VColumn                             53
+#define OP_CreateTable                         54
+#define OP_Last                                55
+#define OP_SeekLe                              56
+#define OP_IsNull                              73   /* same as TK_ISNULL   */
+#define OP_IncrVacuum                          57
+#define OP_IdxRowid                            58
+#define OP_ShiftRight                          85   /* same as TK_RSHIFT   */
+#define OP_ResetCount                          59
+#define OP_Yield                               60
+#define OP_DropTrigger                         61
+#define OP_DropIndex                           62
+#define OP_Param                               63
+#define OP_IdxGE                               64
+#define OP_IdxDelete                           65
+#define OP_Vacuum                              66
+#define OP_IfNot                               67
+#define OP_DropTable                           70
+#define OP_SeekLt                              71
+#define OP_MakeRecord                          72
+#define OP_ToBlob                             142   /* same as TK_TO_BLOB  */
+#define OP_ResultRow                           81
+#define OP_Delete                              92
+#define OP_AggFinal                            95
+#define OP_Compare                             96
+#define OP_ShiftLeft                           84   /* same as TK_LSHIFT   */
+#define OP_Goto                                97
+#define OP_TableLock                           98
+#define OP_Clear                               99
+#define OP_Le                                  78   /* same as TK_LE       */
+#define OP_VerifyCookie                       100
+#define OP_AggStep                            101
+#define OP_ToText                             141   /* same as TK_TO_TEXT  */
+#define OP_Not                                 19   /* same as TK_NOT      */
+#define OP_ToReal                             145   /* same as TK_TO_REAL  */
+#define OP_Transaction                        102
+#define OP_VFilter                            103
+#define OP_Ne                                  75   /* same as TK_NE       */
+#define OP_VDestroy                           104
+#define OP_BitOr                               83   /* same as TK_BITOR    */
+#define OP_Next                               105
+#define OP_Count                              106
+#define OP_IdxInsert                          107
+#define OP_Lt                                  79   /* same as TK_LT       */
+#define OP_FkIfZero                           108
+#define OP_SeekGe                             109
+#define OP_Insert                             110
+#define OP_Destroy                            111
+#define OP_ReadCookie                         112
+#define OP_RowSetTest                         113
+#define OP_LoadAnalysis                       114
+#define OP_Explain                            115
+#define OP_HaltIfNull                         116
+#define OP_OpenPseudo                         117
+#define OP_OpenEphemeral                      118
+#define OP_Null                               119
+#define OP_Move                               120
+#define OP_Blob                               121
+#define OP_Add                                 86   /* same as TK_PLUS     */
+#define OP_Rewind                             122
+#define OP_SeekGt                             123
+#define OP_VBegin                             124
+#define OP_VUpdate                            125
+#define OP_IfZero                             126
+#define OP_BitNot                              93   /* same as TK_BITNOT   */
+#define OP_VCreate                            127
+#define OP_Found                              128
+#define OP_IfPos                              129
+#define OP_NullRow                            131
+#define OP_Jump                               132
+#define OP_Permutation                        133
 
 /* The following opcode values are never used */
-#define OP_NotUsed_126                        126
-#define OP_NotUsed_127                        127
-#define OP_NotUsed_128                        128
-#define OP_NotUsed_129                        129
-#define OP_NotUsed_130                        130
-#define OP_NotUsed_131                        131
-#define OP_NotUsed_132                        132
-#define OP_NotUsed_133                        133
 #define OP_NotUsed_134                        134
 #define OP_NotUsed_135                        135
 #define OP_NotUsed_136                        136
 #define OP_NotUsed_137                        137
+#define OP_NotUsed_138                        138
+#define OP_NotUsed_139                        139
+#define OP_NotUsed_140                        140
 
 
 /* Properties such as "out2" or "jump" that are specified in
@@ -7091,24 +7473,25 @@ typedef struct VdbeOpList VdbeOpList;
 #define OPFLG_IN3             0x0010  /* in3:   P3 is an input */
 #define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */
 #define OPFLG_INITIALIZER {\
-/*   0 */ 0x00, 0x01, 0x00, 0x00, 0x10, 0x02, 0x11, 0x00,\
-/*   8 */ 0x00, 0x00, 0x05, 0x02, 0x00, 0x00, 0x00, 0x00,\
-/*  16 */ 0x04, 0x00, 0x01, 0x00, 0x00, 0x00, 0x05, 0x00,\
-/*  24 */ 0x00, 0x02, 0x02, 0x02, 0x04, 0x00, 0x00, 0x00,\
-/*  32 */ 0x00, 0x02, 0x11, 0x11, 0x02, 0x05, 0x00, 0x02,\
-/*  40 */ 0x11, 0x04, 0x00, 0x00, 0x0c, 0x11, 0x01, 0x02,\
-/*  48 */ 0x01, 0x00, 0x02, 0x01, 0x01, 0x02, 0x00, 0x04,\
-/*  56 */ 0x00, 0x00, 0x00, 0x11, 0x2c, 0x2c, 0x00, 0x00,\
-/*  64 */ 0x11, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
-/*  72 */ 0x15, 0x05, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c,\
-/*  80 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x00, 0x00, 0x00, 0x04,\
-/*  88 */ 0x02, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x11,\
-/*  96 */ 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01,\
-/* 104 */ 0x08, 0x00, 0x02, 0x02, 0x05, 0x00, 0x00, 0x00,\
-/* 112 */ 0x00, 0x02, 0x00, 0x02, 0x01, 0x11, 0x00, 0x00,\
-/* 120 */ 0x05, 0x00, 0x11, 0x05, 0x00, 0x02, 0x00, 0x00,\
-/* 128 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/* 136 */ 0x00, 0x00, 0x04, 0x04, 0x04, 0x04, 0x04,}
+/*   0 */ 0x00, 0x01, 0x00, 0x00, 0x10, 0x08, 0x02, 0x00,\
+/*   8 */ 0x00, 0x04, 0x00, 0x05, 0x00, 0x00, 0x00, 0x00,\
+/*  16 */ 0x02, 0x00, 0x01, 0x04, 0x04, 0x00, 0x00, 0x05,\
+/*  24 */ 0x00, 0x01, 0x04, 0x02, 0x00, 0x00, 0x02, 0x04,\
+/*  32 */ 0x00, 0x00, 0x00, 0x00, 0x02, 0x11, 0x11, 0x02,\
+/*  40 */ 0x05, 0x00, 0x02, 0x11, 0x04, 0x00, 0x08, 0x11,\
+/*  48 */ 0x01, 0x02, 0x01, 0x21, 0x08, 0x00, 0x02, 0x01,\
+/*  56 */ 0x11, 0x01, 0x02, 0x00, 0x04, 0x00, 0x00, 0x02,\
+/*  64 */ 0x11, 0x00, 0x00, 0x05, 0x2c, 0x2c, 0x00, 0x11,\
+/*  72 */ 0x00, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
+/*  80 */ 0x15, 0x00, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c,\
+/*  88 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x00, 0x04, 0x02, 0x00,\
+/*  96 */ 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,\
+/* 104 */ 0x00, 0x01, 0x02, 0x08, 0x01, 0x11, 0x00, 0x02,\
+/* 112 */ 0x02, 0x15, 0x00, 0x00, 0x10, 0x00, 0x00, 0x02,\
+/* 120 */ 0x00, 0x02, 0x01, 0x11, 0x00, 0x00, 0x05, 0x00,\
+/* 128 */ 0x11, 0x05, 0x02, 0x00, 0x01, 0x00, 0x00, 0x00,\
+/* 136 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x04, 0x04,\
+/* 144 */ 0x04, 0x04,}
 
 /************** End of opcodes.h *********************************************/
 /************** Continuing where we left off in vdbe.h ***********************/
@@ -7135,26 +7518,29 @@ SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
 SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
 SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
-SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int);
+SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
 SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
 SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe*);
 #ifdef SQLITE_DEBUG
+SQLITE_PRIVATE   int sqlite3VdbeAssertMayAbort(Vdbe *, int);
 SQLITE_PRIVATE   void sqlite3VdbeTrace(Vdbe*,FILE*);
 #endif
 SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*, int);
+SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe*,int);
-SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, int);
+SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
 SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe*);
 SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
-SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n);
+SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
 SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
+SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *, SubProgram *, int);
 
 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
 SQLITE_PRIVATE int sqlite3VdbeReleaseMemory(int);
 #endif
-SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,void*,int);
+SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,char*,int);
 SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
 SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
 
@@ -7162,8 +7548,11 @@ SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
 #ifndef NDEBUG
 SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
 # define VdbeComment(X)  sqlite3VdbeComment X
+SQLITE_PRIVATE   void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
+# define VdbeNoopComment(X)  sqlite3VdbeNoopComment X
 #else
 # define VdbeComment(X)
+# define VdbeNoopComment(X)
 #endif
 
 #endif
@@ -7187,17 +7576,26 @@ SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
 ** subsystem.  The page cache subsystem reads and writes a file a page
 ** at a time and provides a journal for rollback.
 **
-** @(#) $Id: pager.h,v 1.72 2008/05/01 17:03:49 drh Exp $
+** @(#) $Id: pager.h,v 1.104 2009/07/24 19:01:19 drh Exp $
 */
 
 #ifndef _PAGER_H_
 #define _PAGER_H_
 
 /*
+** Default maximum size for persistent journal files. A negative 
+** value means no limit. This value may be overridden using the 
+** sqlite3PagerJournalSizeLimit() API. See also "PRAGMA journal_size_limit".
+*/
+#ifndef SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT
+  #define SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT -1
+#endif
+
+/*
 ** The type used to represent a page number.  The first page in a file
 ** is called page 1.  0 is used to represent "not a page".
 */
-typedef unsigned int Pgno;
+typedef u32 Pgno;
 
 /*
 ** Each open file is managed by a separate instance of the "Pager" structure.
@@ -7210,9 +7608,19 @@ typedef struct Pager Pager;
 typedef struct PgHdr DbPage;
 
 /*
+** Page number PAGER_MJ_PGNO is never used in an SQLite database (it is
+** reserved for working around a windows/posix incompatibility). It is
+** used in the journal to signify that the remainder of the journal file 
+** is devoted to storing a master journal name - there are no more pages to
+** roll back. See comments for function writeMasterJournal() in pager.c 
+** for details.
+*/
+#define PAGER_MJ_PGNO(x) ((Pgno)((PENDING_BYTE/((x)->pageSize))+1))
+
+/*
 ** Allowed values for the flags parameter to sqlite3PagerOpen().
 **
-** NOTE: This values must match the corresponding BTREE_ values in btree.h.
+** NOTE: These values must match the corresponding BTREE_ values in btree.h.
 */
 #define PAGER_OMIT_JOURNAL  0x0001    /* Do not use a rollback journal */
 #define PAGER_NO_READLOCK   0x0002    /* Omit readlocks on readonly files */
@@ -7231,75 +7639,89 @@ typedef struct PgHdr DbPage;
 #define PAGER_JOURNALMODE_DELETE      0   /* Commit by deleting journal file */
 #define PAGER_JOURNALMODE_PERSIST     1   /* Commit by zeroing journal header */
 #define PAGER_JOURNALMODE_OFF         2   /* Journal omitted.  */
+#define PAGER_JOURNALMODE_TRUNCATE    3   /* Commit by truncating journal */
+#define PAGER_JOURNALMODE_MEMORY      4   /* In-memory journal file */
 
 /*
-** See source code comments for a detailed description of the following
-** routines:
+** The remainder of this file contains the declarations of the functions
+** that make up the Pager sub-system API. See source code comments for 
+** a detailed description of each routine.
 */
-SQLITE_PRIVATE int sqlite3PagerOpen(sqlite3_vfs *, Pager **ppPager, const char*, int,int,int);
-SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, BusyHandler *pBusyHandler);
-SQLITE_PRIVATE void sqlite3PagerSetDestructor(Pager*, void(*)(DbPage*,int));
-SQLITE_PRIVATE void sqlite3PagerSetReiniter(Pager*, void(*)(DbPage*,int));
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*);
-SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
+
+/* Open and close a Pager connection. */ 
+SQLITE_PRIVATE int sqlite3PagerOpen(
+  sqlite3_vfs*,
+  Pager **ppPager,
+  const char*,
+  int,
+  int,
+  int,
+  void(*)(DbPage*)
+);
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
 SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
+
+/* Functions used to configure a Pager object. */
+SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*, int);
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
-SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
+SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int);
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *, int);
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
+
+/* Functions used to obtain and release page references. */ 
 SQLITE_PRIVATE int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
 #define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
 SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
-SQLITE_PRIVATE int sqlite3PagerRef(DbPage*);
-SQLITE_PRIVATE int sqlite3PagerUnref(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage*);
+
+/* Operations on page references. */
 SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*);
-SQLITE_PRIVATE int sqlite3PagerTruncate(Pager*,Pgno);
-SQLITE_PRIVATE int sqlite3PagerBegin(DbPage*, int exFlag);
-SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno, int);
+SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno,int);
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *); 
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *); 
+
+/* Functions used to manage pager transactions and savepoints. */
+SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*, int*);
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
-SQLITE_PRIVATE int sqlite3PagerIsreadonly(Pager*);
-SQLITE_PRIVATE int sqlite3PagerStmtBegin(Pager*);
-SQLITE_PRIVATE int sqlite3PagerStmtCommit(Pager*);
-SQLITE_PRIVATE int sqlite3PagerStmtRollback(Pager*);
-SQLITE_PRIVATE void sqlite3PagerDontRollback(DbPage*);
-SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);
+
+/* Functions used to query pager state and configuration. */
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager*);
 SQLITE_PRIVATE int sqlite3PagerRefcount(Pager*);
-SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int);
 SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*);
 SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager*);
 SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
-SQLITE_PRIVATE const char *sqlite3PagerDirname(Pager*);
 SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
 SQLITE_PRIVATE int sqlite3PagerNosync(Pager*);
-SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno);
-SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *); 
-SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *); 
-SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
-SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *, int);
 SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
-SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
 
-#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
-SQLITE_PRIVATE   int sqlite3PagerReleaseMemory(int);
-#endif
-
-#ifdef SQLITE_HAS_CODEC
-SQLITE_PRIVATE   void sqlite3PagerSetCodec(Pager*,void*(*)(void*,void*,Pgno,int),void*);
-#endif
+/* Functions used to truncate the database file. */
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);
 
+/* Functions to support testing and debugging. */
 #if !defined(NDEBUG) || defined(SQLITE_TEST)
 SQLITE_PRIVATE   Pgno sqlite3PagerPagenumber(DbPage*);
 SQLITE_PRIVATE   int sqlite3PagerIswriteable(DbPage*);
 #endif
-
 #ifdef SQLITE_TEST
 SQLITE_PRIVATE   int *sqlite3PagerStats(Pager*);
 SQLITE_PRIVATE   void sqlite3PagerRefdump(Pager*);
-#endif
-
-#ifdef SQLITE_TEST
-void disable_simulated_io_errors(void);
-void enable_simulated_io_errors(void);
+  void disable_simulated_io_errors(void);
+  void enable_simulated_io_errors(void);
 #else
 # define disable_simulated_io_errors()
 # define enable_simulated_io_errors()
@@ -7309,6 +7731,168 @@ void enable_simulated_io_errors(void);
 
 /************** End of pager.h ***********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pcache.h in the middle of sqliteInt.h ****************/
+/************** Begin file pcache.h ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem. 
+**
+** @(#) $Id: pcache.h,v 1.20 2009/07/25 11:46:49 danielk1977 Exp $
+*/
+
+#ifndef _PCACHE_H_
+
+typedef struct PgHdr PgHdr;
+typedef struct PCache PCache;
+
+/*
+** Every page in the cache is controlled by an instance of the following
+** structure.
+*/
+struct PgHdr {
+  void *pData;                   /* Content of this page */
+  void *pExtra;                  /* Extra content */
+  PgHdr *pDirty;                 /* Transient list of dirty pages */
+  Pgno pgno;                     /* Page number for this page */
+  Pager *pPager;                 /* The pager this page is part of */
+#ifdef SQLITE_CHECK_PAGES
+  u32 pageHash;                  /* Hash of page content */
+#endif
+  u16 flags;                     /* PGHDR flags defined below */
+
+  /**********************************************************************
+  ** Elements above are public.  All that follows is private to pcache.c
+  ** and should not be accessed by other modules.
+  */
+  i16 nRef;                      /* Number of users of this page */
+  PCache *pCache;                /* Cache that owns this page */
+
+  PgHdr *pDirtyNext;             /* Next element in list of dirty pages */
+  PgHdr *pDirtyPrev;             /* Previous element in list of dirty pages */
+};
+
+/* Bit values for PgHdr.flags */
+#define PGHDR_DIRTY             0x002  /* Page has changed */
+#define PGHDR_NEED_SYNC         0x004  /* Fsync the rollback journal before
+                                       ** writing this page to the database */
+#define PGHDR_NEED_READ         0x008  /* Content is unread */
+#define PGHDR_REUSE_UNLIKELY    0x010  /* A hint that reuse is unlikely */
+#define PGHDR_DONT_WRITE        0x020  /* Do not write content to disk */
+
+/* Initialize and shutdown the page cache subsystem */
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
+
+/* Page cache buffer management:
+** These routines implement SQLITE_CONFIG_PAGECACHE.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *, int sz, int n);
+
+/* Create a new pager cache.
+** Under memory stress, invoke xStress to try to make pages clean.
+** Only clean and unpinned pages can be reclaimed.
+*/
+SQLITE_PRIVATE void sqlite3PcacheOpen(
+  int szPage,                    /* Size of every page */
+  int szExtra,                   /* Extra space associated with each page */
+  int bPurgeable,                /* True if pages are on backing store */
+  int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
+  void *pStress,                 /* Argument to xStress */
+  PCache *pToInit                /* Preallocated space for the PCache */
+);
+
+/* Modify the page-size after the cache has been created. */
+SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *, int);
+
+/* Return the size in bytes of a PCache object.  Used to preallocate
+** storage space.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void);
+
+/* One release per successful fetch.  Page is pinned until released.
+** Reference counted. 
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetch(PCache*, Pgno, int createFlag, PgHdr**);
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr*);
+
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr*);         /* Remove page from cache */
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr*);    /* Make sure page is marked dirty */
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr*);    /* Mark a single page as clean */
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache*);    /* Mark all dirty list pages as clean */
+
+/* Change a page number.  Used by incr-vacuum. */
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr*, Pgno);
+
+/* Remove all pages with pgno>x.  Reset the cache if x==0 */
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache*, Pgno x);
+
+/* Get a list of all dirty pages in the cache, sorted by page number */
+SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache*);
+
+/* Reset and close the cache object */
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache*);
+
+/* Clear flags from pages of the page cache */
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *);
+
+/* Discard the contents of the cache */
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache*);
+
+/* Return the total number of outstanding page references */
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);
+
+/* Increment the reference count of an existing page */
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);
+
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);
+
+/* Return the total number of pages stored in the cache */
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);
+
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
+/* Iterate through all dirty pages currently stored in the cache. This
+** interface is only available if SQLITE_CHECK_PAGES is defined when the 
+** library is built.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *));
+#endif
+
+/* Set and get the suggested cache-size for the specified pager-cache.
+**
+** If no global maximum is configured, then the system attempts to limit
+** the total number of pages cached by purgeable pager-caches to the sum
+** of the suggested cache-sizes.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
+#endif
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/* Try to return memory used by the pcache module to the main memory heap */
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
+#endif
+
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
+
+#endif /* _PCACHE_H_ */
+
+/************** End of pcache.h **********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
 
 /************** Include os.h in the middle of sqliteInt.h ********************/
 /************** Begin file os.h **********************************************/
@@ -7330,6 +7914,8 @@ void enable_simulated_io_errors(void);
 **
 ** This header file is #include-ed by sqliteInt.h and thus ends up
 ** being included by every source file.
+**
+** $Id: os.h,v 1.108 2009/02/05 16:31:46 drh Exp $
 */
 #ifndef _SQLITE_OS_H_
 #define _SQLITE_OS_H_
@@ -7337,56 +7923,66 @@ void enable_simulated_io_errors(void);
 /*
 ** Figure out if we are dealing with Unix, Windows, or some other
 ** operating system.  After the following block of preprocess macros,
-** all of OS_UNIX, OS_WIN, OS_OS2, and OS_OTHER will defined to either
-** 1 or 0.  One of the four will be 1.  The other three will be 0.
-*/
-#if defined(OS_OTHER)
-# if OS_OTHER==1
-#   undef OS_UNIX
-#   define OS_UNIX 0
-#   undef OS_WIN
-#   define OS_WIN 0
-#   undef OS_OS2
-#   define OS_OS2 0
+** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER 
+** will defined to either 1 or 0.  One of the four will be 1.  The other 
+** three will be 0.
+*/
+#if defined(SQLITE_OS_OTHER)
+# if SQLITE_OS_OTHER==1
+#   undef SQLITE_OS_UNIX
+#   define SQLITE_OS_UNIX 0
+#   undef SQLITE_OS_WIN
+#   define SQLITE_OS_WIN 0
+#   undef SQLITE_OS_OS2
+#   define SQLITE_OS_OS2 0
 # else
-#   undef OS_OTHER
+#   undef SQLITE_OS_OTHER
 # endif
 #endif
-#if !defined(OS_UNIX) && !defined(OS_OTHER)
-# define OS_OTHER 0
-# ifndef OS_WIN
+#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
+# define SQLITE_OS_OTHER 0
+# ifndef SQLITE_OS_WIN
 #   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
-#     define OS_WIN 1
-#     define OS_UNIX 0
-#     define OS_OS2 0
+#     define SQLITE_OS_WIN 1
+#     define SQLITE_OS_UNIX 0
+#     define SQLITE_OS_OS2 0
 #   elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
-#     define OS_WIN 0
-#     define OS_UNIX 0
-#     define OS_OS2 1
+#     define SQLITE_OS_WIN 0
+#     define SQLITE_OS_UNIX 0
+#     define SQLITE_OS_OS2 1
 #   else
-#     define OS_WIN 0
-#     define OS_UNIX 1
-#     define OS_OS2 0
+#     define SQLITE_OS_WIN 0
+#     define SQLITE_OS_UNIX 1
+#     define SQLITE_OS_OS2 0
 #  endif
 # else
-#  define OS_UNIX 0
-#  define OS_OS2 0
+#  define SQLITE_OS_UNIX 0
+#  define SQLITE_OS_OS2 0
 # endif
 #else
-# ifndef OS_WIN
-#  define OS_WIN 0
+# ifndef SQLITE_OS_WIN
+#  define SQLITE_OS_WIN 0
 # endif
 #endif
 
+/*
+** Determine if we are dealing with WindowsCE - which has a much
+** reduced API.
+*/
+#if defined(_WIN32_WCE)
+# define SQLITE_OS_WINCE 1
+#else
+# define SQLITE_OS_WINCE 0
+#endif
 
 
 /*
 ** Define the maximum size of a temporary filename
 */
-#if OS_WIN
+#if SQLITE_OS_WIN
 # include <windows.h>
 # define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
-#elif OS_OS2
+#elif SQLITE_OS_OS2
 # if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
 #  include <os2safe.h> /* has to be included before os2.h for linking to work */
 # endif
@@ -7497,9 +8093,7 @@ void enable_simulated_io_errors(void);
 ** a random byte is selected for a shared lock.  The pool of bytes for
 ** shared locks begins at SHARED_FIRST. 
 **
-** These #defines are available in sqlite_aux.h so that adaptors for
-** connecting SQLite to other operating systems can use the same byte
-** ranges for locking.  In particular, the same locking strategy and
+** The same locking strategy and
 ** byte ranges are used for Unix.  This leaves open the possiblity of having
 ** clients on win95, winNT, and unix all talking to the same shared file
 ** and all locking correctly.  To do so would require that samba (or whatever
@@ -7523,17 +8117,16 @@ void enable_simulated_io_errors(void);
 ** 1GB boundary.
 **
 */
-#ifndef SQLITE_TEST
-#define PENDING_BYTE      0x40000000  /* First byte past the 1GB boundary */
-#else
-SQLITE_API extern unsigned int sqlite3_pending_byte;
-#define PENDING_BYTE sqlite3_pending_byte
-#endif
-
+#define PENDING_BYTE      sqlite3PendingByte
 #define RESERVED_BYTE     (PENDING_BYTE+1)
 #define SHARED_FIRST      (PENDING_BYTE+2)
 #define SHARED_SIZE       510
 
+/*
+** Wrapper around OS specific sqlite3_os_init() function.
+*/
+SQLITE_PRIVATE int sqlite3OsInit(void);
+
 /* 
 ** Functions for accessing sqlite3_file methods 
 */
@@ -7545,8 +8138,9 @@ SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
 SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
 SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
 SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
-SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
 SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
+#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
 SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
 
@@ -7555,13 +8149,14 @@ SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
 */
 SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
 SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
-SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int);
-SQLITE_PRIVATE int sqlite3OsGetTempname(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
 SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
 SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
 SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
-SQLITE_PRIVATE void *sqlite3OsDlSym(sqlite3_vfs *, void *, const char *);
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
 SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
 SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
 SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
 SQLITE_PRIVATE int sqlite3OsCurrentTime(sqlite3_vfs *, double*);
@@ -7573,16 +8168,6 @@ SQLITE_PRIVATE int sqlite3OsCurrentTime(sqlite3_vfs *, double*);
 SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
 SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
 
-/*
-** Each OS-specific backend defines an instance of the following
-** structure for returning a pointer to its sqlite3_vfs.  If OS_OTHER
-** is defined (meaning that the application-defined OS interface layer
-** is used) then there is no default VFS.   The application must
-** register one or more VFS structures using sqlite3_vfs_register()
-** before attempting to use SQLite.
-*/
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
-
 #endif /* _SQLITE_OS_H_ */
 
 /************** End of os.h **************************************************/
@@ -7610,28 +8195,21 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 ** Source files should #include the sqliteInt.h file and let that file
 ** include this one indirectly.
 **
-** $Id: mutex.h,v 1.2 2007/08/30 14:10:30 drh Exp $
+** $Id: mutex.h,v 1.9 2008/10/07 15:25:48 drh Exp $
 */
 
 
-#ifdef SQLITE_MUTEX_APPDEF
-/*
-** If SQLITE_MUTEX_APPDEF is defined, then this whole module is
-** omitted and equivalent functionality must be provided by the
-** application that links against the SQLite library.
-*/
-#else
 /*
 ** Figure out what version of the code to use.  The choices are
 **
-**   SQLITE_MUTEX_NOOP         For single-threaded applications that
-**                             do not desire error checking.
+**   SQLITE_MUTEX_OMIT         No mutex logic.  Not even stubs.  The
+**                             mutexes implemention cannot be overridden
+**                             at start-time.
 **
-**   SQLITE_MUTEX_NOOP_DEBUG   For single-threaded applications with
-**                             error checking to help verify that mutexes
-**                             are being used correctly even though they
-**                             are not needed.  Used when SQLITE_DEBUG is
-**                             defined on single-threaded builds.
+**   SQLITE_MUTEX_NOOP         For single-threaded applications.  No
+**                             mutual exclusion is provided.  But this
+**                             implementation can be overridden at
+**                             start-time.
 **
 **   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
 **
@@ -7639,25 +8217,22 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 **
 **   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
 */
-#define SQLITE_MUTEX_NOOP 1   /* The default */
-#if defined(SQLITE_DEBUG) && !SQLITE_THREADSAFE
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_NOOP_DEBUG
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_UNIX
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_PTHREADS
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_WIN
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_W32
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_OS2
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_OS2
+#if !SQLITE_THREADSAFE
+# define SQLITE_MUTEX_OMIT
+#endif
+#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
+#  if SQLITE_OS_UNIX
+#    define SQLITE_MUTEX_PTHREADS
+#  elif SQLITE_OS_WIN
+#    define SQLITE_MUTEX_W32
+#  elif SQLITE_OS_OS2
+#    define SQLITE_MUTEX_OS2
+#  else
+#    define SQLITE_MUTEX_NOOP
+#  endif
 #endif
 
-#ifdef SQLITE_MUTEX_NOOP
+#ifdef SQLITE_MUTEX_OMIT
 /*
 ** If this is a no-op implementation, implement everything as macros.
 */
@@ -7668,9 +8243,10 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 #define sqlite3_mutex_leave(X)
 #define sqlite3_mutex_held(X)     1
 #define sqlite3_mutex_notheld(X)  1
-#endif
-
-#endif /* SQLITE_MUTEX_APPDEF */
+#define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
+#define sqlite3MutexInit()        SQLITE_OK
+#define sqlite3MutexEnd()
+#endif /* defined(SQLITE_MUTEX_OMIT) */
 
 /************** End of mutex.h ***********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
@@ -7687,9 +8263,7 @@ struct Db {
   char *zName;         /* Name of this database */
   Btree *pBt;          /* The B*Tree structure for this database file */
   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
-  u8 safety_level;     /* How aggressive at synching data to disk */
-  void *pAux;               /* Auxiliary data.  Usually NULL */
-  void (*xFreeAux)(void*);  /* Routine to free pAux */
+  u8 safety_level;     /* How aggressive at syncing data to disk */
   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
 };
 
@@ -7709,7 +8283,7 @@ struct Schema {
   Hash tblHash;        /* All tables indexed by name */
   Hash idxHash;        /* All (named) indices indexed by name */
   Hash trigHash;       /* All triggers indexed by name */
-  Hash aFKey;          /* Foreign keys indexed by to-table */
+  Hash fkeyHash;       /* All foreign keys by referenced table name */
   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
   u8 file_format;      /* Schema format version for this file */
   u8 enc;              /* Text encoding used by this database */
@@ -7747,7 +8321,51 @@ struct Schema {
 ** The number of different kinds of things that can be limited
 ** using the sqlite3_limit() interface.
 */
-#define SQLITE_N_LIMIT (SQLITE_LIMIT_VARIABLE_NUMBER+1)
+#define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
+
+/*
+** Lookaside malloc is a set of fixed-size buffers that can be used
+** to satisfy small transient memory allocation requests for objects
+** associated with a particular database connection.  The use of
+** lookaside malloc provides a significant performance enhancement
+** (approx 10%) by avoiding numerous malloc/free requests while parsing
+** SQL statements.
+**
+** The Lookaside structure holds configuration information about the
+** lookaside malloc subsystem.  Each available memory allocation in
+** the lookaside subsystem is stored on a linked list of LookasideSlot
+** objects.
+**
+** Lookaside allocations are only allowed for objects that are associated
+** with a particular database connection.  Hence, schema information cannot
+** be stored in lookaside because in shared cache mode the schema information
+** is shared by multiple database connections.  Therefore, while parsing
+** schema information, the Lookaside.bEnabled flag is cleared so that
+** lookaside allocations are not used to construct the schema objects.
+*/
+struct Lookaside {
+  u16 sz;                 /* Size of each buffer in bytes */
+  u8 bEnabled;            /* False to disable new lookaside allocations */
+  u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
+  int nOut;               /* Number of buffers currently checked out */
+  int mxOut;              /* Highwater mark for nOut */
+  LookasideSlot *pFree;   /* List of available buffers */
+  void *pStart;           /* First byte of available memory space */
+  void *pEnd;             /* First byte past end of available space */
+};
+struct LookasideSlot {
+  LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
+};
+
+/*
+** A hash table for function definitions.
+**
+** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
+** Collisions are on the FuncDef.pHash chain.
+*/
+struct FuncDefHash {
+  FuncDef *a[23];       /* Hash table for functions */
+};
 
 /*
 ** Each database is an instance of the following structure.
@@ -7779,7 +8397,7 @@ struct sqlite3 {
   sqlite3_vfs *pVfs;            /* OS Interface */
   int nDb;                      /* Number of backends currently in use */
   Db *aDb;                      /* All backends */
-  int flags;                    /* Miscellanous flags. See below */
+  int flags;                    /* Miscellaneous flags. See below */
   int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
   int errCode;                  /* Most recent error code (SQLITE_*) */
   int errMask;                  /* & result codes with this before returning */
@@ -7793,8 +8411,7 @@ struct sqlite3 {
   int nTable;                   /* Number of tables in the database */
   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
   i64 lastRowid;                /* ROWID of most recent insert (see above) */
-  i64 priorNewRowid;            /* Last randomly generated ROWID */
-  int magic;                    /* Magic number for detect library misuse */
+  u32 magic;                    /* Magic number for detect library misuse */
   int nChange;                  /* Value returned by sqlite3_changes() */
   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
   sqlite3_mutex *mutex;         /* Connection mutex */
@@ -7803,11 +8420,13 @@ struct sqlite3 {
     int iDb;                    /* When back is being initialized */
     int newTnum;                /* Rootpage of table being initialized */
     u8 busy;                    /* TRUE if currently initializing */
+    u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
   } init;
   int nExtension;               /* Number of loaded extensions */
-  void **aExtension;            /* Array of shared libraray handles */
+  void **aExtension;            /* Array of shared library handles */
   struct Vdbe *pVdbe;           /* List of active virtual machines */
-  int activeVdbeCnt;            /* Number of vdbes currently executing */
+  int activeVdbeCnt;            /* Number of VDBEs currently executing */
+  int writeVdbeCnt;             /* Number of active VDBEs that are writing */
   void (*xTrace)(void*,const char*);        /* Trace function */
   void *pTraceArg;                          /* Argument to the trace function */
   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
@@ -7825,9 +8444,10 @@ struct sqlite3 {
   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
   union {
-    int isInterrupted;          /* True if sqlite3_interrupt has been called */
+    volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
     double notUsed1;            /* Spacer */
   } u1;
+  Lookaside lookaside;          /* Lookaside malloc configuration */
 #ifndef SQLITE_OMIT_AUTHORIZATION
   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
                                 /* Access authorization function */
@@ -7841,16 +8461,37 @@ struct sqlite3 {
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   Hash aModule;                 /* populated by sqlite3_create_module() */
   Table *pVTab;                 /* vtab with active Connect/Create method */
-  sqlite3_vtab **aVTrans;       /* Virtual tables with open transactions */
+  VTable **aVTrans;             /* Virtual tables with open transactions */
   int nVTrans;                  /* Allocated size of aVTrans */
+  VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
 #endif
-  Hash aFunc;                   /* All functions that can be in SQL exprs */
+  FuncDefHash aFunc;            /* Hash table of connection functions */
   Hash aCollSeq;                /* All collating sequences */
   BusyHandler busyHandler;      /* Busy callback */
   int busyTimeout;              /* Busy handler timeout, in msec */
   Db aDbStatic[2];              /* Static space for the 2 default backends */
-#ifdef SQLITE_SSE
-  sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
+  Savepoint *pSavepoint;        /* List of active savepoints */
+  int nSavepoint;               /* Number of non-transaction savepoints */
+  int nStatement;               /* Number of nested statement-transactions  */
+  u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
+  i64 nDeferredCons;            /* Net deferred constraints this transaction. */
+
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+  /* The following variables are all protected by the STATIC_MASTER 
+  ** mutex, not by sqlite3.mutex. They are used by code in notify.c. 
+  **
+  ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
+  ** unlock so that it can proceed.
+  **
+  ** When X.pBlockingConnection==Y, that means that something that X tried
+  ** tried to do recently failed with an SQLITE_LOCKED error due to locks
+  ** held by Y.
+  */
+  sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
+  sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
+  void *pUnlockArg;                     /* Argument to xUnlockNotify */
+  void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
+  sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
 #endif
 };
 
@@ -7888,8 +8529,9 @@ struct sqlite3 {
 #define SQLITE_LoadExtension  0x00020000  /* Enable load_extension */
 
 #define SQLITE_RecoveryMode   0x00040000  /* Ignore schema errors */
-#define SQLITE_SharedCache    0x00080000  /* Cache sharing is enabled */
-#define SQLITE_Vtab           0x00100000  /* There exists a virtual table */
+#define SQLITE_ReverseOrder   0x00100000  /* Reverse unordered SELECTs */
+#define SQLITE_RecTriggers    0x00200000  /* Enable recursive triggers */
+#define SQLITE_ForeignKeys    0x00400000  /* Enforce foreign key constraints  */
 
 /*
 ** Possible values for the sqlite.magic field.
@@ -7911,17 +8553,85 @@ struct sqlite3 {
 struct FuncDef {
   i16 nArg;            /* Number of arguments.  -1 means unlimited */
   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
-  u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
   u8 flags;            /* Some combination of SQLITE_FUNC_* */
   void *pUserData;     /* User data parameter */
   FuncDef *pNext;      /* Next function with same name */
   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
-  void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
-  char zName[1];       /* SQL name of the function.  MUST BE LAST */
+  void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
+  char *zName;         /* SQL name of the function. */
+  FuncDef *pHash;      /* Next with a different name but the same hash */
+};
+
+/*
+** Possible values for FuncDef.flags
+*/
+#define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
+#define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
+#define SQLITE_FUNC_EPHEM    0x04 /* Ephemeral.  Delete with VDBE */
+#define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
+#define SQLITE_FUNC_PRIVATE  0x10 /* Allowed for internal use only */
+#define SQLITE_FUNC_COUNT    0x20 /* Built-in count(*) aggregate */
+
+/*
+** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
+** used to create the initializers for the FuncDef structures.
+**
+**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
+**     Used to create a scalar function definition of a function zName 
+**     implemented by C function xFunc that accepts nArg arguments. The
+**     value passed as iArg is cast to a (void*) and made available
+**     as the user-data (sqlite3_user_data()) for the function. If 
+**     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
+**
+**   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
+**     Used to create an aggregate function definition implemented by
+**     the C functions xStep and xFinal. The first four parameters
+**     are interpreted in the same way as the first 4 parameters to
+**     FUNCTION().
+**
+**   LIKEFUNC(zName, nArg, pArg, flags)
+**     Used to create a scalar function definition of a function zName 
+**     that accepts nArg arguments and is implemented by a call to C 
+**     function likeFunc. Argument pArg is cast to a (void *) and made
+**     available as the function user-data (sqlite3_user_data()). The
+**     FuncDef.flags variable is set to the value passed as the flags
+**     parameter.
+*/
+#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
+  {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
+   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0}
+#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
+  {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
+   pArg, 0, xFunc, 0, 0, #zName, 0}
+#define LIKEFUNC(zName, nArg, arg, flags) \
+  {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0}
+#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
+  {nArg, SQLITE_UTF8, nc*SQLITE_FUNC_NEEDCOLL, \
+   SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0}
+
+/*
+** All current savepoints are stored in a linked list starting at
+** sqlite3.pSavepoint. The first element in the list is the most recently
+** opened savepoint. Savepoints are added to the list by the vdbe
+** OP_Savepoint instruction.
+*/
+struct Savepoint {
+  char *zName;                        /* Savepoint name (nul-terminated) */
+  i64 nDeferredCons;                  /* Number of deferred fk violations */
+  Savepoint *pNext;                   /* Parent savepoint (if any) */
 };
 
 /*
+** The following are used as the second parameter to sqlite3Savepoint(),
+** and as the P1 argument to the OP_Savepoint instruction.
+*/
+#define SAVEPOINT_BEGIN      0
+#define SAVEPOINT_RELEASE    1
+#define SAVEPOINT_ROLLBACK   2
+
+
+/*
 ** Each SQLite module (virtual table definition) is defined by an
 ** instance of the following structure, stored in the sqlite3.aModule
 ** hash table.
@@ -7934,19 +8644,13 @@ struct Module {
 };
 
 /*
-** Possible values for FuncDef.flags
-*/
-#define SQLITE_FUNC_LIKE   0x01  /* Candidate for the LIKE optimization */
-#define SQLITE_FUNC_CASE   0x02  /* Case-sensitive LIKE-type function */
-#define SQLITE_FUNC_EPHEM  0x04  /* Ephermeral.  Delete with VDBE */
-
-/*
 ** information about each column of an SQL table is held in an instance
 ** of this structure.
 */
 struct Column {
   char *zName;     /* Name of this column */
   Expr *pDflt;     /* Default value of this column */
+  char *zDflt;     /* Original text of the default value */
   char *zType;     /* Data type for this column */
   char *zColl;     /* Collating sequence.  If NULL, use the default */
   u8 notNull;      /* True if there is a NOT NULL constraint */
@@ -7962,7 +8666,7 @@ struct Column {
 ** structure. Conceptually, a collating sequence consists of a name and
 ** a comparison routine that defines the order of that sequence.
 **
-** There may two seperate implementations of the collation function, one
+** There may two separate implementations of the collation function, one
 ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
 ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
 ** native byte order. When a collation sequence is invoked, SQLite selects
@@ -7988,7 +8692,7 @@ struct CollSeq {
 };
 
 /*
-** Allowed values of CollSeq flags:
+** Allowed values of CollSeq.type:
 */
 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
@@ -8006,7 +8710,7 @@ struct CollSeq {
 **
 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
-** the speed a little by number the values consecutively.  
+** the speed a little by numbering the values consecutively.  
 **
 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
 ** when multiple affinity types are concatenated into a string and
@@ -8034,8 +8738,58 @@ struct CollSeq {
 ** changing the affinity.
 */
 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
-#define SQLITE_NULLEQUAL    0x10  /* compare NULLs equal */
-#define SQLITE_STOREP2      0x80  /* Store result in reg[P2] rather than jump */
+#define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
+#define SQLITE_NULLEQ       0x80  /* NULL=NULL */
+
+/*
+** An object of this type is created for each virtual table present in
+** the database schema. 
+**
+** If the database schema is shared, then there is one instance of this
+** structure for each database connection (sqlite3*) that uses the shared
+** schema. This is because each database connection requires its own unique
+** instance of the sqlite3_vtab* handle used to access the virtual table 
+** implementation. sqlite3_vtab* handles can not be shared between 
+** database connections, even when the rest of the in-memory database 
+** schema is shared, as the implementation often stores the database
+** connection handle passed to it via the xConnect() or xCreate() method
+** during initialization internally. This database connection handle may
+** then used by the virtual table implementation to access real tables 
+** within the database. So that they appear as part of the callers 
+** transaction, these accesses need to be made via the same database 
+** connection as that used to execute SQL operations on the virtual table.
+**
+** All VTable objects that correspond to a single table in a shared
+** database schema are initially stored in a linked-list pointed to by
+** the Table.pVTable member variable of the corresponding Table object.
+** When an sqlite3_prepare() operation is required to access the virtual
+** table, it searches the list for the VTable that corresponds to the
+** database connection doing the preparing so as to use the correct
+** sqlite3_vtab* handle in the compiled query.
+**
+** When an in-memory Table object is deleted (for example when the
+** schema is being reloaded for some reason), the VTable objects are not 
+** deleted and the sqlite3_vtab* handles are not xDisconnect()ed 
+** immediately. Instead, they are moved from the Table.pVTable list to
+** another linked list headed by the sqlite3.pDisconnect member of the
+** corresponding sqlite3 structure. They are then deleted/xDisconnected 
+** next time a statement is prepared using said sqlite3*. This is done
+** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
+** Refer to comments above function sqlite3VtabUnlockList() for an
+** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
+** list without holding the corresponding sqlite3.mutex mutex.
+**
+** The memory for objects of this type is always allocated by 
+** sqlite3DbMalloc(), using the connection handle stored in VTable.db as 
+** the first argument.
+*/
+struct VTable {
+  sqlite3 *db;              /* Database connection associated with this table */
+  Module *pMod;             /* Pointer to module implementation */
+  sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
+  int nRef;                 /* Number of pointers to this structure */
+  VTable *pNext;            /* Next in linked list (see above) */
+};
 
 /*
 ** Each SQL table is represented in memory by an instance of the
@@ -8053,14 +8807,14 @@ struct CollSeq {
 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
-** is generated for each row of the table.  Table.hasPrimKey is true if
+** is generated for each row of the table.  TF_HasPrimaryKey is set if
 ** the table has any PRIMARY KEY, INTEGER or otherwise.
 **
 ** Table.tnum is the page number for the root BTree page of the table in the
 ** database file.  If Table.iDb is the index of the database table backend
 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
-** holds temporary tables and indices.  If Table.isEphem
-** is true, then the table is stored in a file that is automatically deleted
+** holds temporary tables and indices.  If TF_Ephemeral is set
+** then the table is stored in a file that is automatically deleted
 ** when the VDBE cursor to the table is closed.  In this case Table.tnum 
 ** refers VDBE cursor number that holds the table open, not to the root
 ** page number.  Transient tables are used to hold the results of a
@@ -8068,46 +8822,54 @@ struct CollSeq {
 ** of a SELECT statement.
 */
 struct Table {
-  char *zName;     /* Name of the table */
-  int nCol;        /* Number of columns in this table */
-  Column *aCol;    /* Information about each column */
-  int iPKey;       /* If not less then 0, use aCol[iPKey] as the primary key */
-  Index *pIndex;   /* List of SQL indexes on this table. */
-  int tnum;        /* Root BTree node for this table (see note above) */
-  Select *pSelect; /* NULL for tables.  Points to definition if a view. */
-  int nRef;          /* Number of pointers to this Table */
-  Trigger *pTrigger; /* List of SQL triggers on this table */
-  FKey *pFKey;       /* Linked list of all foreign keys in this table */
-  char *zColAff;     /* String defining the affinity of each column */
+  sqlite3 *dbMem;      /* DB connection used for lookaside allocations. */
+  char *zName;         /* Name of the table or view */
+  int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
+  int nCol;            /* Number of columns in this table */
+  Column *aCol;        /* Information about each column */
+  Index *pIndex;       /* List of SQL indexes on this table. */
+  int tnum;            /* Root BTree node for this table (see note above) */
+  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
+  u16 nRef;            /* Number of pointers to this Table */
+  u8 tabFlags;         /* Mask of TF_* values */
+  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
+  FKey *pFKey;         /* Linked list of all foreign keys in this table */
+  char *zColAff;       /* String defining the affinity of each column */
 #ifndef SQLITE_OMIT_CHECK
-  Expr *pCheck;      /* The AND of all CHECK constraints */
+  Expr *pCheck;        /* The AND of all CHECK constraints */
 #endif
 #ifndef SQLITE_OMIT_ALTERTABLE
-  int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
+  int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
 #endif
-  u8 readOnly;     /* True if this table should not be written by the user */
-  u8 isEphem;      /* True if created using OP_OpenEphermeral */
-  u8 hasPrimKey;   /* True if there exists a primary key */
-  u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
-  u8 autoInc;      /* True if the integer primary key is autoincrement */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  u8 isVirtual;             /* True if this is a virtual table */
-  u8 isCommit;              /* True once the CREATE TABLE has been committed */
-  Module *pMod;             /* Pointer to the implementation of the module */
-  sqlite3_vtab *pVtab;      /* Pointer to the module instance */
-  int nModuleArg;           /* Number of arguments to the module */
-  char **azModuleArg;       /* Text of all module args. [0] is module name */
-#endif
-  Schema *pSchema;          /* Schema that contains this table */
+  VTable *pVTable;     /* List of VTable objects. */
+  int nModuleArg;      /* Number of arguments to the module */
+  char **azModuleArg;  /* Text of all module args. [0] is module name */
+#endif
+  Trigger *pTrigger;   /* List of triggers stored in pSchema */
+  Schema *pSchema;     /* Schema that contains this table */
+  Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
 };
 
 /*
+** Allowed values for Tabe.tabFlags.
+*/
+#define TF_Readonly        0x01    /* Read-only system table */
+#define TF_Ephemeral       0x02    /* An ephemeral table */
+#define TF_HasPrimaryKey   0x04    /* Table has a primary key */
+#define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
+#define TF_Virtual         0x10    /* Is a virtual table */
+#define TF_NeedMetadata    0x20    /* aCol[].zType and aCol[].pColl missing */
+
+
+
+/*
 ** Test to see whether or not a table is a virtual table.  This is
 ** done as a macro so that it will be optimized out when virtual
 ** table support is omitted from the build.
 */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-#  define IsVirtual(X)      ((X)->isVirtual)
+#  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
 #  define IsHiddenColumn(X) ((X)->isHidden)
 #else
 #  define IsVirtual(X)      0
@@ -8131,28 +8893,23 @@ struct Table {
 **
 ** Each REFERENCES clause generates an instance of the following structure
 ** which is attached to the from-table.  The to-table need not exist when
-** the from-table is created.  The existance of the to-table is not checked
-** until an attempt is made to insert data into the from-table.
-**
-** The sqlite.aFKey hash table stores pointers to this structure
-** given the name of a to-table.  For each to-table, all foreign keys
-** associated with that table are on a linked list using the FKey.pNextTo
-** field.
+** the from-table is created.  The existence of the to-table is not checked.
 */
 struct FKey {
-  Table *pFrom;     /* The table that constains the REFERENCES clause */
+  Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
   FKey *pNextFrom;  /* Next foreign key in pFrom */
-  char *zTo;        /* Name of table that the key points to */
-  FKey *pNextTo;    /* Next foreign key that points to zTo */
+  char *zTo;        /* Name of table that the key points to (aka: Parent) */
+  FKey *pNextTo;    /* Next foreign key on table named zTo */
+  FKey *pPrevTo;    /* Previous foreign key on table named zTo */
   int nCol;         /* Number of columns in this key */
+  /* EV: R-30323-21917 */
+  u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
+  u8 aAction[2];          /* ON DELETE and ON UPDATE actions, respectively */
+  Trigger *apTrigger[2];  /* Triggers for aAction[] actions */
   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
     int iFrom;         /* Index of column in pFrom */
     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
-  } *aCol;          /* One entry for each of nCol column s */
-  u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
-  u8 updateConf;    /* How to resolve conflicts that occur on UPDATE */
-  u8 deleteConf;    /* How to resolve conflicts that occur on DELETE */
-  u8 insertConf;    /* How to resolve conflicts that occur on INSERT */
+  } aCol[1];        /* One entry for each of nCol column s */
 };
 
 /*
@@ -8199,22 +8956,48 @@ struct FKey {
 ** An instance of the following structure is passed as the first
 ** argument to sqlite3VdbeKeyCompare and is used to control the 
 ** comparison of the two index keys.
-**
-** If the KeyInfo.incrKey value is true and the comparison would
-** otherwise be equal, then return a result as if the second key
-** were larger.
 */
 struct KeyInfo {
   sqlite3 *db;        /* The database connection */
   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
-  u8 incrKey;         /* Increase 2nd key by epsilon before comparison */
-  u8 prefixIsEqual;   /* Treat a prefix as equal */
-  int nField;         /* Number of entries in aColl[] */
+  u16 nField;         /* Number of entries in aColl[] */
   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
 };
 
 /*
+** An instance of the following structure holds information about a
+** single index record that has already been parsed out into individual
+** values.
+**
+** A record is an object that contains one or more fields of data.
+** Records are used to store the content of a table row and to store
+** the key of an index.  A blob encoding of a record is created by
+** the OP_MakeRecord opcode of the VDBE and is disassembled by the
+** OP_Column opcode.
+**
+** This structure holds a record that has already been disassembled
+** into its constituent fields.
+*/
+struct UnpackedRecord {
+  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
+  u16 nField;         /* Number of entries in apMem[] */
+  u16 flags;          /* Boolean settings.  UNPACKED_... below */
+  i64 rowid;          /* Used by UNPACKED_PREFIX_SEARCH */
+  Mem *aMem;          /* Values */
+};
+
+/*
+** Allowed values of UnpackedRecord.flags
+*/
+#define UNPACKED_NEED_FREE     0x0001  /* Memory is from sqlite3Malloc() */
+#define UNPACKED_NEED_DESTROY  0x0002  /* apMem[]s should all be destroyed */
+#define UNPACKED_IGNORE_ROWID  0x0004  /* Ignore trailing rowid on key1 */
+#define UNPACKED_INCRKEY       0x0008  /* Make this key an epsilon larger */
+#define UNPACKED_PREFIX_MATCH  0x0010  /* A prefix match is considered OK */
+#define UNPACKED_PREFIX_SEARCH 0x0020  /* A prefix match is considered OK */
+
+/*
 ** Each SQL index is represented in memory by an
 ** instance of the following structure.
 **
@@ -8254,6 +9037,20 @@ struct Index {
   Schema *pSchema; /* Schema containing this index */
   u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
   char **azColl;   /* Array of collation sequence names for index */
+  IndexSample *aSample;    /* Array of SQLITE_INDEX_SAMPLES samples */
+};
+
+/*
+** Each sample stored in the sqlite_stat2 table is represented in memory 
+** using a structure of this type.
+*/
+struct IndexSample {
+  union {
+    char *z;        /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
+    double r;       /* Value if eType is SQLITE_FLOAT or SQLITE_INTEGER */
+  } u;
+  u8 eType;         /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
+  u8 nByte;         /* Size in byte of text or blob. */
 };
 
 /*
@@ -8261,13 +9058,12 @@ struct Index {
 ** this structure.  Tokens are also used as part of an expression.
 **
 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
-** may contain random values.  Do not make any assuptions about Token.dyn
+** may contain random values.  Do not make any assumptions about Token.dyn
 ** and Token.n when Token.z==0.
 */
 struct Token {
-  const unsigned char *z; /* Text of the token.  Not NULL-terminated! */
-  unsigned dyn  : 1;      /* True for malloced memory, false for static */
-  unsigned n    : 31;     /* Number of characters in this token */
+  const char *z;     /* Text of the token.  Not NULL-terminated! */
+  unsigned int n;    /* Number of characters in this token */
 };
 
 /*
@@ -8308,7 +9104,7 @@ struct AggInfo {
     Expr *pExpr;             /* Expression encoding the function */
     FuncDef *pFunc;          /* The aggregate function implementation */
     int iMem;                /* Memory location that acts as accumulator */
-    int iDistinct;           /* Ephermeral table used to enforce DISTINCT */
+    int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
   } *aFunc;
   int nFunc;              /* Number of entries in aFunc[] */
   int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
@@ -8318,19 +9114,27 @@ struct AggInfo {
 ** Each node of an expression in the parse tree is an instance
 ** of this structure.
 **
-** Expr.op is the opcode.  The integer parser token codes are reused
-** as opcodes here.  For example, the parser defines TK_GE to be an integer
-** code representing the ">=" operator.  This same integer code is reused
+** Expr.op is the opcode. The integer parser token codes are reused
+** as opcodes here. For example, the parser defines TK_GE to be an integer
+** code representing the ">=" operator. This same integer code is reused
 ** to represent the greater-than-or-equal-to operator in the expression
 ** tree.
 **
-** Expr.pRight and Expr.pLeft are subexpressions.  Expr.pList is a list
-** of argument if the expression is a function.
+** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB, 
+** or TK_STRING), then Expr.token contains the text of the SQL literal. If
+** the expression is a variable (TK_VARIABLE), then Expr.token contains the 
+** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
+** then Expr.token contains the name of the function.
 **
-** Expr.token is the operator token for this node.  For some expressions
-** that have subexpressions, Expr.token can be the complete text that gave
-** rise to the Expr.  In the latter case, the token is marked as being
-** a compound token.
+** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
+** binary operator. Either or both may be NULL.
+**
+** Expr.x.pList is a list of arguments if the expression is an SQL function,
+** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
+** Expr.x.pSelect is used if the expression is a sub-select or an expression of
+** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
+** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is 
+** valid.
 **
 ** An expression of the form ID or ID.ID refers to a column in a table.
 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
@@ -8340,10 +9144,9 @@ struct AggInfo {
 ** value is also stored in the Expr.iAgg column in the aggregate so that
 ** it can be accessed after all aggregates are computed.
 **
-** If the expression is a function, the Expr.iTable is an integer code
-** representing which function.  If the expression is an unbound variable
-** marker (a question mark character '?' in the original SQL) then the
-** Expr.iTable holds the index number for that variable.
+** If the expression is an unbound variable marker (a question mark 
+** character '?' in the original SQL) then the Expr.iTable holds the index 
+** number for that variable.
 **
 ** If the expression is a subquery then Expr.iColumn holds an integer
 ** register number containing the result of the subquery.  If the
@@ -8351,35 +9154,63 @@ struct AggInfo {
 ** gives a different answer at different times during statement processing
 ** then iTable is the address of a subroutine that computes the subquery.
 **
-** The Expr.pSelect field points to a SELECT statement.  The SELECT might
-** be the right operand of an IN operator.  Or, if a scalar SELECT appears
-** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
-** operand.
-**
 ** If the Expr is of type OP_Column, and the table it is selecting from
 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
 ** corresponding table definition.
+**
+** ALLOCATION NOTES:
+**
+** Expr objects can use a lot of memory space in database schema.  To
+** help reduce memory requirements, sometimes an Expr object will be
+** truncated.  And to reduce the number of memory allocations, sometimes
+** two or more Expr objects will be stored in a single memory allocation,
+** together with Expr.zToken strings.
+**
+** If the EP_Reduced and EP_TokenOnly flags are set when
+** an Expr object is truncated.  When EP_Reduced is set, then all
+** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
+** are contained within the same memory allocation.  Note, however, that
+** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
+** allocated, regardless of whether or not EP_Reduced is set.
 */
 struct Expr {
   u8 op;                 /* Operation performed by this node */
   char affinity;         /* The affinity of the column or 0 if not a column */
-  u16 flags;             /* Various flags.  See below */
+  u16 flags;             /* Various flags.  EP_* See below */
+  union {
+    char *zToken;          /* Token value. Zero terminated and dequoted */
+    int iValue;            /* Integer value if EP_IntValue */
+  } u;
+
+  /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
+  ** space is allocated for the fields below this point. An attempt to
+  ** access them will result in a segfault or malfunction. 
+  *********************************************************************/
+
+  Expr *pLeft;           /* Left subnode */
+  Expr *pRight;          /* Right subnode */
+  union {
+    ExprList *pList;     /* Function arguments or in "<expr> IN (<expr-list)" */
+    Select *pSelect;     /* Used for sub-selects and "<expr> IN (<select>)" */
+  } x;
   CollSeq *pColl;        /* The collation type of the column or 0 */
-  Expr *pLeft, *pRight;  /* Left and right subnodes */
-  ExprList *pList;       /* A list of expressions used as function arguments
-                         ** or in "<expr> IN (<expr-list)" */
-  Token token;           /* An operand token */
-  Token span;            /* Complete text of the expression */
-  int iTable, iColumn;   /* When op==TK_COLUMN, then this expr node means the
-                         ** iColumn-th field of the iTable-th table. */
+
+  /* If the EP_Reduced flag is set in the Expr.flags mask, then no
+  ** space is allocated for the fields below this point. An attempt to
+  ** access them will result in a segfault or malfunction.
+  *********************************************************************/
+
+  int iTable;            /* TK_COLUMN: cursor number of table holding column
+                         ** TK_REGISTER: register number
+                         ** TK_TRIGGER: 1 -> new, 0 -> old */
+  i16 iColumn;           /* TK_COLUMN: column index.  -1 for rowid */
+  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
+  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
+  u8 flags2;             /* Second set of flags.  EP2_... */
+  u8 op2;                /* If a TK_REGISTER, the original value of Expr.op */
   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
-  int iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
-  int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
-  Select *pSelect;       /* When the expression is a sub-select.  Also the
-                         ** right side of "<expr> IN (<select>)" */
-  Table *pTab;           /* Table for OP_Column expressions. */
-/*  Schema *pSchema; */
-#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
+  Table *pTab;           /* Table for TK_COLUMN expressions. */
+#if SQLITE_MAX_EXPR_DEPTH>0
   int nHeight;           /* Height of the tree headed by this node */
 #endif
 };
@@ -8393,11 +9224,35 @@ struct Expr {
 #define EP_Error      0x0008  /* Expression contains one or more errors */
 #define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
-#define EP_Dequoted   0x0040  /* True if the string has been dequoted */
+#define EP_DblQuoted  0x0040  /* token.z was originally in "..." */
 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
 #define EP_ExpCollate 0x0100  /* Collating sequence specified explicitly */
 #define EP_AnyAff     0x0200  /* Can take a cached column of any affinity */
 #define EP_FixedDest  0x0400  /* Result needed in a specific register */
+#define EP_IntValue   0x0800  /* Integer value contained in u.iValue */
+#define EP_xIsSelect  0x1000  /* x.pSelect is valid (otherwise x.pList is) */
+
+#define EP_Reduced    0x2000  /* Expr struct is EXPR_REDUCEDSIZE bytes only */
+#define EP_TokenOnly  0x4000  /* Expr struct is EXPR_TOKENONLYSIZE bytes only */
+#define EP_Static     0x8000  /* Held in memory not obtained from malloc() */
+
+/*
+** The following are the meanings of bits in the Expr.flags2 field.
+*/
+#define EP2_MallocedToken  0x0001  /* Need to sqlite3DbFree() Expr.zToken */
+#define EP2_Irreducible    0x0002  /* Cannot EXPRDUP_REDUCE this Expr */
+
+/*
+** The pseudo-routine sqlite3ExprSetIrreducible sets the EP2_Irreducible
+** flag on an expression structure.  This flag is used for VV&A only.  The
+** routine is implemented as a macro that only works when in debugging mode,
+** so as not to burden production code.
+*/
+#ifdef SQLITE_DEBUG
+# define ExprSetIrreducible(X)  (X)->flags2 |= EP2_Irreducible
+#else
+# define ExprSetIrreducible(X)
+#endif
 
 /*
 ** These macros can be used to test, set, or clear bits in the 
@@ -8409,6 +9264,21 @@ struct Expr {
 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
 
 /*
+** Macros to determine the number of bytes required by a normal Expr 
+** struct, an Expr struct with the EP_Reduced flag set in Expr.flags 
+** and an Expr struct with the EP_TokenOnly flag set.
+*/
+#define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
+#define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
+#define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
+
+/*
+** Flags passed to the sqlite3ExprDup() function. See the header comment 
+** above sqlite3ExprDup() for details.
+*/
+#define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
+
+/*
 ** A list of expressions.  Each expression may optionally have a
 ** name.  An expr/name combination can be used in several ways, such
 ** as the list of "expr AS ID" fields following a "SELECT" or in the
@@ -8423,13 +9293,26 @@ struct ExprList {
   struct ExprList_item {
     Expr *pExpr;           /* The list of expressions */
     char *zName;           /* Token associated with this expression */
+    char *zSpan;           /* Original text of the expression */
     u8 sortOrder;          /* 1 for DESC or 0 for ASC */
-    u8 isAgg;              /* True if this is an aggregate like count(*) */
     u8 done;               /* A flag to indicate when processing is finished */
+    u16 iCol;              /* For ORDER BY, column number in result set */
+    u16 iAlias;            /* Index into Parse.aAlias[] for zName */
   } *a;                  /* One entry for each expression */
 };
 
 /*
+** An instance of this structure is used by the parser to record both
+** the parse tree for an expression and the span of input text for an
+** expression.
+*/
+struct ExprSpan {
+  Expr *pExpr;          /* The expression parse tree */
+  const char *zStart;   /* First character of input text */
+  const char *zEnd;     /* One character past the end of input text */
+};
+
+/*
 ** An instance of this structure can hold a simple list of identifiers,
 ** such as the list "a,b,c" in the following statements:
 **
@@ -8463,6 +9346,11 @@ struct IdList {
 typedef u64 Bitmask;
 
 /*
+** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
+*/
+#define BMS  ((int)(sizeof(Bitmask)*8))
+
+/*
 ** The following structure describes the FROM clause of a SELECT statement.
 ** Each table or subquery in the FROM clause is a separate element of
 ** the SrcList.a[] array.
@@ -8489,10 +9377,13 @@ struct SrcList {
     Select *pSelect;  /* A SELECT statement used in place of a table name */
     u8 isPopulated;   /* Temporary table associated with SELECT is populated */
     u8 jointype;      /* Type of join between this able and the previous */
+    u8 notIndexed;    /* True if there is a NOT INDEXED clause */
     int iCursor;      /* The VDBE cursor number used to access this table */
     Expr *pOn;        /* The ON clause of a join */
     IdList *pUsing;   /* The USING clause of a join */
-    Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
+    Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
+    char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
+    Index *pIndex;    /* Index structure corresponding to zIndex, if any */
   } a[1];             /* One entry for each identifier on the list */
 };
 
@@ -8507,60 +9398,87 @@ struct SrcList {
 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
 
+
+/*
+** A WherePlan object holds information that describes a lookup
+** strategy.
+**
+** This object is intended to be opaque outside of the where.c module.
+** It is included here only so that that compiler will know how big it
+** is.  None of the fields in this object should be used outside of
+** the where.c module.
+**
+** Within the union, pIdx is only used when wsFlags&WHERE_INDEXED is true.
+** pTerm is only used when wsFlags&WHERE_MULTI_OR is true.  And pVtabIdx
+** is only used when wsFlags&WHERE_VIRTUALTABLE is true.  It is never the
+** case that more than one of these conditions is true.
+*/
+struct WherePlan {
+  u32 wsFlags;                   /* WHERE_* flags that describe the strategy */
+  u32 nEq;                       /* Number of == constraints */
+  union {
+    Index *pIdx;                   /* Index when WHERE_INDEXED is true */
+    struct WhereTerm *pTerm;       /* WHERE clause term for OR-search */
+    sqlite3_index_info *pVtabIdx;  /* Virtual table index to use */
+  } u;
+};
+
 /*
 ** For each nested loop in a WHERE clause implementation, the WhereInfo
 ** structure contains a single instance of this structure.  This structure
 ** is intended to be private the the where.c module and should not be
 ** access or modified by other modules.
 **
-** The pIdxInfo and pBestIdx fields are used to help pick the best
-** index on a virtual table.  The pIdxInfo pointer contains indexing
+** The pIdxInfo field is used to help pick the best index on a
+** virtual table.  The pIdxInfo pointer contains indexing
 ** information for the i-th table in the FROM clause before reordering.
 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
-** The pBestIdx pointer is a copy of pIdxInfo for the i-th table after
-** FROM clause ordering.  This is a little confusing so I will repeat
-** it in different words.  WhereInfo.a[i].pIdxInfo is index information 
-** for WhereInfo.pTabList.a[i].  WhereInfo.a[i].pBestInfo is the
-** index information for the i-th loop of the join.  pBestInfo is always
-** either NULL or a copy of some pIdxInfo.  So for cleanup it is 
-** sufficient to free all of the pIdxInfo pointers.
-** 
+** All other information in the i-th WhereLevel object for the i-th table
+** after FROM clause ordering.
 */
 struct WhereLevel {
-  int iFrom;            /* Which entry in the FROM clause */
-  int flags;            /* Flags associated with this level */
-  int iMem;             /* First memory cell used by this level */
+  WherePlan plan;       /* query plan for this element of the FROM clause */
   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
-  Index *pIdx;          /* Index used.  NULL if no index */
   int iTabCur;          /* The VDBE cursor used to access the table */
-  int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
-  int brk;              /* Jump here to break out of the loop */
-  int nxt;              /* Jump here to start the next IN combination */
-  int cont;             /* Jump here to continue with the next loop cycle */
-  int top;              /* First instruction of interior of the loop */
-  int op, p1, p2;       /* Opcode used to terminate the loop */
-  int nEq;              /* Number of == or IN constraints on this loop */
-  int nIn;              /* Number of IN operators constraining this loop */
-  struct InLoop {
-    int iCur;              /* The VDBE cursor used by this IN operator */
-    int topAddr;           /* Top of the IN loop */
-  } *aInLoop;           /* Information about each nested IN operator */
-  sqlite3_index_info *pBestIdx;  /* Index information for this level */
+  int iIdxCur;          /* The VDBE cursor used to access pIdx */
+  int addrBrk;          /* Jump here to break out of the loop */
+  int addrNxt;          /* Jump here to start the next IN combination */
+  int addrCont;         /* Jump here to continue with the next loop cycle */
+  int addrFirst;        /* First instruction of interior of the loop */
+  u8 iFrom;             /* Which entry in the FROM clause */
+  u8 op, p5;            /* Opcode and P5 of the opcode that ends the loop */
+  int p1, p2;           /* Operands of the opcode used to ends the loop */
+  union {               /* Information that depends on plan.wsFlags */
+    struct {
+      int nIn;              /* Number of entries in aInLoop[] */
+      struct InLoop {
+        int iCur;              /* The VDBE cursor used by this IN operator */
+        int addrInTop;         /* Top of the IN loop */
+      } *aInLoop;           /* Information about each nested IN operator */
+    } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
+  } u;
 
   /* The following field is really not part of the current level.  But
-  ** we need a place to cache index information for each table in the
-  ** FROM clause and the WhereLevel structure is a convenient place.
+  ** we need a place to cache virtual table index information for each
+  ** virtual table in the FROM clause and the WhereLevel structure is
+  ** a convenient place since there is one WhereLevel for each FROM clause
+  ** element.
   */
   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
 };
 
 /*
-** Flags appropriate for the wflags parameter of sqlite3WhereBegin().
+** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
+** and the WhereInfo.wctrlFlags member.
 */
-#define WHERE_ORDERBY_NORMAL     0   /* No-op */
-#define WHERE_ORDERBY_MIN        1   /* ORDER BY processing for min() func */
-#define WHERE_ORDERBY_MAX        2   /* ORDER BY processing for max() func */
-#define WHERE_ONEPASS_DESIRED    4   /* Want to do one-pass UPDATE/DELETE */
+#define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
+#define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
+#define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
+#define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
+#define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
+#define WHERE_OMIT_OPEN        0x0010 /* Table cursor are already open */
+#define WHERE_OMIT_CLOSE       0x0020 /* Omit close of table & index cursors */
+#define WHERE_FORCE_TABLE      0x0040 /* Do not use an index-only search */
 
 /*
 ** The WHERE clause processing routine has two halves.  The
@@ -8571,14 +9489,15 @@ struct WhereLevel {
 */
 struct WhereInfo {
   Parse *pParse;       /* Parsing and code generating context */
+  u16 wctrlFlags;      /* Flags originally passed to sqlite3WhereBegin() */
   u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
-  SrcList *pTabList;   /* List of tables in the join */
-  int iTop;            /* The very beginning of the WHERE loop */
-  int iContinue;       /* Jump here to continue with next record */
-  int iBreak;          /* Jump here to break out of the loop */
-  int nLevel;          /* Number of nested loop */
-  sqlite3_index_info **apInfo;  /* Array of pointers to index info structures */
-  WhereLevel a[1];     /* Information about each nest loop in the WHERE */
+  SrcList *pTabList;             /* List of tables in the join */
+  int iTop;                      /* The very beginning of the WHERE loop */
+  int iContinue;                 /* Jump here to continue with next record */
+  int iBreak;                    /* Jump here to break out of the loop */
+  int nLevel;                    /* Number of nested loop */
+  struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
+  WhereLevel a[1];               /* Information about each nest loop in WHERE */
 };
 
 /*
@@ -8639,12 +9558,8 @@ struct NameContext {
 struct Select {
   ExprList *pEList;      /* The fields of the result */
   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
-  u8 isDistinct;         /* True if the DISTINCT keyword is present */
-  u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
-  u8 isAgg;              /* True if this is an aggregate query */
-  u8 usesEphm;           /* True if uses an OpenEphemeral opcode */
-  u8 disallowOrderBy;    /* Do not allow an ORDER BY to be attached if TRUE */
   char affinity;         /* MakeRecord with this affinity for SRT_Set */
+  u16 selFlags;          /* Various SF_* values */
   SrcList *pSrc;         /* The FROM clause */
   Expr *pWhere;          /* The WHERE clause */
   ExprList *pGroupBy;    /* The GROUP BY clause */
@@ -8660,7 +9575,20 @@ struct Select {
 };
 
 /*
-** The results of a select can be distributed in several ways.
+** Allowed values for Select.selFlags.  The "SF" prefix stands for
+** "Select Flag".
+*/
+#define SF_Distinct        0x0001  /* Output should be DISTINCT */
+#define SF_Resolved        0x0002  /* Identifiers have been resolved */
+#define SF_Aggregate       0x0004  /* Contains aggregate functions */
+#define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
+#define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
+#define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
+
+
+/*
+** The results of a select can be distributed in several ways.  The
+** "SRT" prefix means "SELECT Result Type".
 */
 #define SRT_Union        1  /* Store result as keys in an index */
 #define SRT_Except       2  /* Remove result from a UNION index */
@@ -8670,15 +9598,15 @@ struct Select {
 /* The ORDER BY clause is ignored for all of the above */
 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
 
-#define SRT_Callback     5  /* Invoke a callback with each row of result */
+#define SRT_Output       5  /* Output each row of result */
 #define SRT_Mem          6  /* Store result in a memory cell */
-#define SRT_Set          7  /* Store non-null results as keys in an index */
+#define SRT_Set          7  /* Store results as keys in an index */
 #define SRT_Table        8  /* Store result as data with an automatic rowid */
 #define SRT_EphemTab     9  /* Create transient tab and store like SRT_Table */
-#define SRT_Subroutine  10  /* Call a subroutine to handle results */
+#define SRT_Coroutine   10  /* Generate a single row of result */
 
 /*
-** A structure used to customize the behaviour of sqlite3Select(). See
+** A structure used to customize the behavior of sqlite3Select(). See
 ** comments above sqlite3Select() for details.
 */
 typedef struct SelectDest SelectDest;
@@ -8691,6 +9619,54 @@ struct SelectDest {
 };
 
 /*
+** During code generation of statements that do inserts into AUTOINCREMENT 
+** tables, the following information is attached to the Table.u.autoInc.p
+** pointer of each autoincrement table to record some side information that
+** the code generator needs.  We have to keep per-table autoincrement
+** information in case inserts are down within triggers.  Triggers do not
+** normally coordinate their activities, but we do need to coordinate the
+** loading and saving of autoincrement information.
+*/
+struct AutoincInfo {
+  AutoincInfo *pNext;   /* Next info block in a list of them all */
+  Table *pTab;          /* Table this info block refers to */
+  int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
+  int regCtr;           /* Memory register holding the rowid counter */
+};
+
+/*
+** Size of the column cache
+*/
+#ifndef SQLITE_N_COLCACHE
+# define SQLITE_N_COLCACHE 10
+#endif
+
+/*
+** At least one instance of the following structure is created for each 
+** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
+** statement. All such objects are stored in the linked list headed at
+** Parse.pTriggerPrg and deleted once statement compilation has been
+** completed.
+**
+** A Vdbe sub-program that implements the body and WHEN clause of trigger
+** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
+** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
+** The Parse.pTriggerPrg list never contains two entries with the same
+** values for both pTrigger and orconf.
+**
+** The TriggerPrg.oldmask variable is set to a mask of old.* columns
+** accessed (or set to 0 for triggers fired as a result of INSERT 
+** statements).
+*/
+struct TriggerPrg {
+  Trigger *pTrigger;      /* Trigger this program was coded from */
+  int orconf;             /* Default ON CONFLICT policy */
+  SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
+  u32 oldmask;            /* Mask of old.* columns accessed */
+  TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
+};
+
+/*
 ** An SQL parser context.  A copy of this structure is passed through
 ** the parser and down into all the parser action routine in order to
 ** carry around information that is global to the entire parse.
@@ -8726,17 +9702,23 @@ struct Parse {
   int nMem;            /* Number of memory cells used so far */
   int nSet;            /* Number of sets used so far */
   int ckBase;          /* Base register of data during check constraints */
-  int disableColCache; /* True to disable adding to column cache */
-  int nColCache;       /* Number of entries in the column cache */
-  int iColCache;       /* Next entry of the cache to replace */
+  int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
+  int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
+  u8 nColCache;        /* Number of entries in the column cache */
+  u8 iColCache;        /* Next entry of the cache to replace */
   struct yColCache {
     int iTable;           /* Table cursor number */
     int iColumn;          /* Table column number */
-    char affChange;       /* True if this register has had an affinity change */
-    int iReg;             /* Register holding value of this column */
-  } aColCache[10];     /* One for each valid column cache entry */
+    u8 affChange;         /* True if this register has had an affinity change */
+    u8 tempReg;           /* iReg is a temp register that needs to be freed */
+    int iLevel;           /* Nesting level */
+    int iReg;             /* Reg with value of this column. 0 means none. */
+    int lru;              /* Least recently used entry has the smallest value */
+  } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
   u32 writeMask;       /* Start a write transaction on these databases */
   u32 cookieMask;      /* Bitmask of schema verified databases */
+  u8 isMultiWrite;     /* True if statement may affect/insert multiple rows */
+  u8 mayAbort;         /* True if statement may throw an ABORT exception */
   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
 #ifndef SQLITE_OMIT_SHARED_CACHE
@@ -8745,6 +9727,16 @@ struct Parse {
 #endif
   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
   int regRoot;         /* Register holding root page number for new objects */
+  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
+  int nMaxArg;         /* Max args passed to user function by sub-program */
+
+  /* Information used while coding trigger programs. */
+  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
+  Table *pTriggerTab;  /* Table triggers are being coded for */
+  u32 oldmask;         /* Mask of old.* columns referenced */
+  u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
+  u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
+  u8 disableTriggers;  /* True to disable triggers */
 
   /* Above is constant between recursions.  Below is reset before and after
   ** each recursion */
@@ -8753,15 +9745,15 @@ struct Parse {
   int nVarExpr;        /* Number of used slots in apVarExpr[] */
   int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
   Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
+  int nAlias;          /* Number of aliased result set columns */
+  int nAliasAlloc;     /* Number of allocated slots for aAlias[] */
+  int *aAlias;         /* Register used to hold aliased result */
   u8 explain;          /* True if the EXPLAIN flag is found on the query */
-  Token sErrToken;     /* The token at which the error occurred */
   Token sNameToken;    /* Token with unqualified schema object name */
   Token sLastToken;    /* The last token parsed */
-  const char *zSql;    /* All SQL text */
   const char *zTail;   /* All SQL text past the last semicolon parsed */
   Table *pNewTable;    /* A table being constructed by CREATE TABLE */
   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
-  TriggerStack *trigStack;  /* Trigger actions being coded */
   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   Token sArg;                /* Complete text of a module argument */
@@ -8769,9 +9761,9 @@ struct Parse {
   int nVtabLock;             /* Number of virtual tables to lock */
   Table **apVtabLock;        /* Pointer to virtual tables needing locking */
 #endif
-#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
   int nHeight;            /* Expression tree height of current sub-select */
-#endif
+  Table *pZombieTab;      /* List of Table objects to delete after code gen */
+  TriggerPrg *pTriggerPrg;    /* Linked list of coded triggers */
 };
 
 #ifdef SQLITE_OMIT_VIRTUALTABLE
@@ -8790,12 +9782,14 @@ struct AuthContext {
 };
 
 /*
-** Bitfield flags for P2 value in OP_Insert and OP_Delete
+** Bitfield flags for P5 value in OP_Insert and OP_Delete
 */
-#define OPFLAG_NCHANGE   1    /* Set to update db->nChange */
-#define OPFLAG_LASTROWID 2    /* Set to update db->lastRowid */
-#define OPFLAG_ISUPDATE  4    /* This OP_Insert is an sql UPDATE */
-#define OPFLAG_APPEND    8    /* This is likely to be an append */
+#define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
+#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
+#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
+#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
+#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
+#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
 
 /*
  * Each trigger present in the database schema is stored as an instance of
@@ -8813,14 +9807,13 @@ struct AuthContext {
  * containing the SQL statements specified as the trigger program.
  */
 struct Trigger {
-  char *name;             /* The name of the trigger                        */
+  char *zName;            /* The name of the trigger                        */
   char *table;            /* The table or view to which the trigger applies */
   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
-  Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
+  Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
                              the <column-list> is stored here */
-  Token nameToken;        /* Token containing zName. Use during parsing only */
   Schema *pSchema;        /* Schema containing the trigger */
   Schema *pTabSchema;     /* Schema containing the table */
   TriggerStep *step_list; /* Link list of trigger program steps             */
@@ -8854,7 +9847,7 @@ struct Trigger {
  * orconf    -> stores the ON CONFLICT algorithm
  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
  *              this stores a pointer to the SELECT statement. Otherwise NULL.
- * target    -> A token holding the name of the table to insert into.
+ * target    -> A token holding the quoted name of the table to insert into.
  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
  *              this stores values to be inserted. Otherwise NULL.
  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ... 
@@ -8862,12 +9855,12 @@ struct Trigger {
  *              inserted into.
  *
  * (op == TK_DELETE)
- * target    -> A token holding the name of the table to delete from.
+ * target    -> A token holding the quoted name of the table to delete from.
  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
  *              Otherwise NULL.
  * 
  * (op == TK_UPDATE)
- * target    -> A token holding the name of the table to update rows of.
+ * target    -> A token holding the quoted name of the table to update rows of.
  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
  *              Otherwise NULL.
  * pExprList -> A list of the columns to update and the expressions to update
@@ -8876,61 +9869,19 @@ struct Trigger {
  * 
  */
 struct TriggerStep {
-  int op;              /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
-  int orconf;          /* OE_Rollback etc. */
+  u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
+  u8 orconf;           /* OE_Rollback etc. */
   Trigger *pTrig;      /* The trigger that this step is a part of */
-
-  Select *pSelect;     /* Valid for SELECT and sometimes 
-                          INSERT steps (when pExprList == 0) */
-  Token target;        /* Valid for DELETE, UPDATE, INSERT steps */
-  Expr *pWhere;        /* Valid for DELETE, UPDATE steps */
-  ExprList *pExprList; /* Valid for UPDATE statements and sometimes 
-                           INSERT steps (when pSelect == 0)         */
-  IdList *pIdList;     /* Valid for INSERT statements only */
+  Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
+  Token target;        /* Target table for DELETE, UPDATE, INSERT */
+  Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
+  ExprList *pExprList; /* SET clause for UPDATE.  VALUES clause for INSERT */
+  IdList *pIdList;     /* Column names for INSERT */
   TriggerStep *pNext;  /* Next in the link-list */
   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
 };
 
 /*
- * An instance of struct TriggerStack stores information required during code
- * generation of a single trigger program. While the trigger program is being
- * coded, its associated TriggerStack instance is pointed to by the
- * "pTriggerStack" member of the Parse structure.
- *
- * The pTab member points to the table that triggers are being coded on. The 
- * newIdx member contains the index of the vdbe cursor that points at the temp
- * table that stores the new.* references. If new.* references are not valid
- * for the trigger being coded (for example an ON DELETE trigger), then newIdx
- * is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
- *
- * The ON CONFLICT policy to be used for the trigger program steps is stored 
- * as the orconf member. If this is OE_Default, then the ON CONFLICT clause 
- * specified for individual triggers steps is used.
- *
- * struct TriggerStack has a "pNext" member, to allow linked lists to be
- * constructed. When coding nested triggers (triggers fired by other triggers)
- * each nested trigger stores its parent trigger's TriggerStack as the "pNext" 
- * pointer. Once the nested trigger has been coded, the pNext value is restored
- * to the pTriggerStack member of the Parse stucture and coding of the parent
- * trigger continues.
- *
- * Before a nested trigger is coded, the linked list pointed to by the 
- * pTriggerStack is scanned to ensure that the trigger is not about to be coded
- * recursively. If this condition is detected, the nested trigger is not coded.
- */
-struct TriggerStack {
-  Table *pTab;         /* Table that triggers are currently being coded on */
-  int newIdx;          /* Index of vdbe cursor to "new" temp table */
-  int oldIdx;          /* Index of vdbe cursor to "old" temp table */
-  u32 newColMask;
-  u32 oldColMask;
-  int orconf;          /* Current orconf policy */
-  int ignoreJump;      /* where to jump to for a RAISE(IGNORE) */
-  Trigger *pTrigger;   /* The trigger currently being coded */
-  TriggerStack *pNext; /* Next trigger down on the trigger stack */
-};
-
-/*
 ** The following structure contains information used by the sqliteFix...
 ** routines as they walk the parse tree to make database references
 ** explicit.  
@@ -8948,13 +9899,14 @@ struct DbFixer {
 ** do not necessarily know how big the string will be in the end.
 */
 struct StrAccum {
-  char *zBase;     /* A base allocation.  Not from malloc. */
-  char *zText;     /* The string collected so far */
-  int  nChar;      /* Length of the string so far */
-  int  nAlloc;     /* Amount of space allocated in zText */
+  sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
+  char *zBase;         /* A base allocation.  Not from malloc. */
+  char *zText;         /* The string collected so far */
+  int  nChar;          /* Length of the string so far */
+  int  nAlloc;         /* Amount of space allocated in zText */
   int  mxAlloc;        /* Maximum allowed string length */
   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
-  u8   useMalloc;      /* True if zText is enlargable using realloc */
+  u8   useMalloc;      /* True if zText is enlargeable using realloc */
   u8   tooBig;         /* Becomes true if string size exceeds limits */
 };
 
@@ -8970,6 +9922,71 @@ typedef struct {
 } InitData;
 
 /*
+** Structure containing global configuration data for the SQLite library.
+**
+** This structure also contains some state information.
+*/
+struct Sqlite3Config {
+  int bMemstat;                     /* True to enable memory status */
+  int bCoreMutex;                   /* True to enable core mutexing */
+  int bFullMutex;                   /* True to enable full mutexing */
+  int mxStrlen;                     /* Maximum string length */
+  int szLookaside;                  /* Default lookaside buffer size */
+  int nLookaside;                   /* Default lookaside buffer count */
+  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
+  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
+  sqlite3_pcache_methods pcache;    /* Low-level page-cache interface */
+  void *pHeap;                      /* Heap storage space */
+  int nHeap;                        /* Size of pHeap[] */
+  int mnReq, mxReq;                 /* Min and max heap requests sizes */
+  void *pScratch;                   /* Scratch memory */
+  int szScratch;                    /* Size of each scratch buffer */
+  int nScratch;                     /* Number of scratch buffers */
+  void *pPage;                      /* Page cache memory */
+  int szPage;                       /* Size of each page in pPage[] */
+  int nPage;                        /* Number of pages in pPage[] */
+  int mxParserStack;                /* maximum depth of the parser stack */
+  int sharedCacheEnabled;           /* true if shared-cache mode enabled */
+  /* The above might be initialized to non-zero.  The following need to always
+  ** initially be zero, however. */
+  int isInit;                       /* True after initialization has finished */
+  int inProgress;                   /* True while initialization in progress */
+  int isMutexInit;                  /* True after mutexes are initialized */
+  int isMallocInit;                 /* True after malloc is initialized */
+  int isPCacheInit;                 /* True after malloc is initialized */
+  sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
+  int nRefInitMutex;                /* Number of users of pInitMutex */
+};
+
+/*
+** Context pointer passed down through the tree-walk.
+*/
+struct Walker {
+  int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
+  int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
+  Parse *pParse;                            /* Parser context.  */
+  union {                                   /* Extra data for callback */
+    NameContext *pNC;                          /* Naming context */
+    int i;                                     /* Integer value */
+  } u;
+};
+
+/* Forward declarations */
+SQLITE_PRIVATE int sqlite3WalkExpr(Walker*, Expr*);
+SQLITE_PRIVATE int sqlite3WalkExprList(Walker*, ExprList*);
+SQLITE_PRIVATE int sqlite3WalkSelect(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker*, Select*);
+
+/*
+** Return code from the parse-tree walking primitives and their
+** callbacks.
+*/
+#define WRC_Continue    0   /* Continue down into children */
+#define WRC_Prune       1   /* Omit children but continue walking siblings */
+#define WRC_Abort       2   /* Abandon the tree walk */
+
+/*
 ** Assuming zIn points to the first byte of a UTF-8 character,
 ** advance zIn to point to the first byte of the next UTF-8 character.
 */
@@ -8988,45 +10005,125 @@ typedef struct {
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE   int sqlite3Corrupt(void);
 # define SQLITE_CORRUPT_BKPT sqlite3Corrupt()
-# define DEBUGONLY(X)        X
 #else
 # define SQLITE_CORRUPT_BKPT SQLITE_CORRUPT
-# define DEBUGONLY(X)
+#endif
+
+/*
+** The ctype.h header is needed for non-ASCII systems.  It is also
+** needed by FTS3 when FTS3 is included in the amalgamation.
+*/
+#if !defined(SQLITE_ASCII) || \
+    (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
+# include <ctype.h>
+#endif
+
+/*
+** The following macros mimic the standard library functions toupper(),
+** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
+** sqlite versions only work for ASCII characters, regardless of locale.
+*/
+#ifdef SQLITE_ASCII
+# define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
+# define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
+# define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
+# define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
+# define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
+# define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
+# define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
+#else
+# define sqlite3Toupper(x)   toupper((unsigned char)(x))
+# define sqlite3Isspace(x)   isspace((unsigned char)(x))
+# define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
+# define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
+# define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
+# define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
+# define sqlite3Tolower(x)   tolower((unsigned char)(x))
 #endif
 
 /*
 ** Internal function prototypes
 */
 SQLITE_PRIVATE int sqlite3StrICmp(const char *, const char *);
-SQLITE_PRIVATE int sqlite3StrNICmp(const char *, const char *, int);
 SQLITE_PRIVATE int sqlite3IsNumber(const char*, int*, u8);
-
-SQLITE_PRIVATE void *sqlite3MallocZero(unsigned);
-SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3*, unsigned);
-SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3*, unsigned);
-SQLITE_PRIVATE char *sqlite3StrDup(const char*);
-SQLITE_PRIVATE char *sqlite3StrNDup(const char*, int);
+SQLITE_PRIVATE int sqlite3Strlen30(const char*);
+#define sqlite3StrNICmp sqlite3_strnicmp
+
+SQLITE_PRIVATE int sqlite3MallocInit(void);
+SQLITE_PRIVATE void sqlite3MallocEnd(void);
+SQLITE_PRIVATE void *sqlite3Malloc(int);
+SQLITE_PRIVATE void *sqlite3MallocZero(int);
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3*, int);
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3*, int);
 SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3*,const char*);
 SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3*,const char*, int);
+SQLITE_PRIVATE void *sqlite3Realloc(void*, int);
 SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
 SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *, void *, int);
-SQLITE_PRIVATE int sqlite3MallocSize(void *);
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3*, void*);
+SQLITE_PRIVATE int sqlite3MallocSize(void*);
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3*, void*);
+SQLITE_PRIVATE void *sqlite3ScratchMalloc(int);
+SQLITE_PRIVATE void sqlite3ScratchFree(void*);
+SQLITE_PRIVATE void *sqlite3PageMalloc(int);
+SQLITE_PRIVATE void sqlite3PageFree(void*);
+SQLITE_PRIVATE void sqlite3MemSetDefault(void);
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
+SQLITE_PRIVATE int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);
+
+/*
+** On systems with ample stack space and that support alloca(), make
+** use of alloca() to obtain space for large automatic objects.  By default,
+** obtain space from malloc().
+**
+** The alloca() routine never returns NULL.  This will cause code paths
+** that deal with sqlite3StackAlloc() failures to be unreachable.
+*/
+#ifdef SQLITE_USE_ALLOCA
+# define sqlite3StackAllocRaw(D,N)   alloca(N)
+# define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
+# define sqlite3StackFree(D,P)       
+#else
+# define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
+# define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
+# define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
+#endif
+
+#ifdef SQLITE_ENABLE_MEMSYS3
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS5
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
+#endif
+
+
+#ifndef SQLITE_MUTEX_OMIT
+SQLITE_PRIVATE   sqlite3_mutex_methods *sqlite3DefaultMutex(void);
+SQLITE_PRIVATE   sqlite3_mutex *sqlite3MutexAlloc(int);
+SQLITE_PRIVATE   int sqlite3MutexInit(void);
+SQLITE_PRIVATE   int sqlite3MutexEnd(void);
+#endif
+
+SQLITE_PRIVATE int sqlite3StatusValue(int);
+SQLITE_PRIVATE void sqlite3StatusAdd(int, int);
+SQLITE_PRIVATE void sqlite3StatusSet(int, int);
 
 SQLITE_PRIVATE int sqlite3IsNaN(double);
 
+SQLITE_PRIVATE void sqlite3VXPrintf(StrAccum*, int, const char*, va_list);
 SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3*,const char*, ...);
 SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
+SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
 SQLITE_PRIVATE   void sqlite3DebugPrintf(const char*, ...);
 #endif
 #if defined(SQLITE_TEST)
-SQLITE_PRIVATE   void *sqlite3TextToPtr(const char*);
+SQLITE_PRIVATE   void *sqlite3TestTextToPtr(const char*);
 #endif
-SQLITE_PRIVATE void sqlite3SetString(char **, ...);
+SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*, ...);
 SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
 SQLITE_PRIVATE void sqlite3ErrorClear(Parse*);
-SQLITE_PRIVATE void sqlite3Dequote(char*);
-SQLITE_PRIVATE void sqlite3DequoteExpr(sqlite3*, Expr*);
+SQLITE_PRIVATE int sqlite3Dequote(char*);
 SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);
 SQLITE_PRIVATE int sqlite3RunParser(Parse*, const char*, char **);
 SQLITE_PRIVATE void sqlite3FinishCoding(Parse*);
@@ -9034,23 +10131,26 @@ SQLITE_PRIVATE int sqlite3GetTempReg(Parse*);
 SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse*,int);
 SQLITE_PRIVATE int sqlite3GetTempRange(Parse*,int);
 SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse*,int,int);
-SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*, int, Expr*, Expr*, const Token*);
+SQLITE_PRIVATE Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
+SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
 SQLITE_PRIVATE Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
-SQLITE_PRIVATE Expr *sqlite3RegisterExpr(Parse*,Token*);
 SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
-SQLITE_PRIVATE void sqlite3ExprSpan(Expr*,Token*,Token*);
 SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
 SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*);
-SQLITE_PRIVATE void sqlite3ExprDelete(Expr*);
-SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
-SQLITE_PRIVATE void sqlite3ExprListDelete(ExprList*);
+SQLITE_PRIVATE void sqlite3ExprClear(sqlite3*, Expr*);
+SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
+SQLITE_PRIVATE void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
+SQLITE_PRIVATE void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
+SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
 SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
 SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
 SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
 SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3*, int);
 SQLITE_PRIVATE void sqlite3BeginParse(Parse*,int);
 SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3*);
-SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,char*,Select*);
+SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,Select*);
 SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *, int);
 SQLITE_PRIVATE void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
 SQLITE_PRIVATE void sqlite3AddColumn(Parse*,Token*);
@@ -9058,17 +10158,24 @@ SQLITE_PRIVATE void sqlite3AddNotNull(Parse*, int);
 SQLITE_PRIVATE void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
 SQLITE_PRIVATE void sqlite3AddCheckConstraint(Parse*, Expr*);
 SQLITE_PRIVATE void sqlite3AddColumnType(Parse*,Token*);
-SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,Expr*);
+SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,ExprSpan*);
 SQLITE_PRIVATE void sqlite3AddCollateType(Parse*, Token*);
 SQLITE_PRIVATE void sqlite3EndTable(Parse*,Token*,Token*,Select*);
 
 SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32);
 SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec*, u32);
 SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec*, u32);
-SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec*, u32);
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec*, u32, void*);
 SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec*);
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec*);
 SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int,int*);
 
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
+SQLITE_PRIVATE void sqlite3RowSetClear(RowSet*);
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet*, i64);
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet*, u8 iBatch, i64);
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet*, i64*);
+
 SQLITE_PRIVATE void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
 
 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
@@ -9079,36 +10186,53 @@ SQLITE_PRIVATE   int sqlite3ViewGetColumnNames(Parse*,Table*);
 
 SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
 SQLITE_PRIVATE void sqlite3DeleteTable(Table*);
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+SQLITE_PRIVATE   void sqlite3AutoincrementBegin(Parse *pParse);
+SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
+#else
+# define sqlite3AutoincrementBegin(X)
+# define sqlite3AutoincrementEnd(X)
+#endif
 SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
 SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
 SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
 SQLITE_PRIVATE int sqlite3IdListIndex(IdList*,const char*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
 SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
-SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*, Token*,
-                                      Select*, Expr*, IdList*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
+                                      Token*, Select*, Expr*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
+SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
 SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList*);
 SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse*, SrcList*);
-SQLITE_PRIVATE void sqlite3IdListDelete(IdList*);
-SQLITE_PRIVATE void sqlite3SrcListDelete(SrcList*);
-SQLITE_PRIVATE void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
+SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3*, SrcList*);
+SQLITE_PRIVATE Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                         Token*, int, int);
 SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
-SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*, Select*, int, int*, char *aff);
+SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
 SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                          Expr*,ExprList*,int,Expr*,Expr*);
-SQLITE_PRIVATE void sqlite3SelectDelete(Select*);
+SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
 SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
 SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
 SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
+#endif
 SQLITE_PRIVATE void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
 SQLITE_PRIVATE void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
-SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u8);
+SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u16);
 SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo*);
 SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, int);
-SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int);
-SQLITE_PRIVATE void sqlite3ExprClearColumnCache(Parse*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCachePush(Parse*);
+SQLITE_PRIVATE void sqlite3ExprCachePop(Parse*, int);
+SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int);
+SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);
 SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse*, int, int);
-SQLITE_PRIVATE int sqlite3ExprWritableRegister(Parse*,int,int);
 SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse*,int,int);
 SQLITE_PRIVATE int sqlite3ExprCode(Parse*, Expr*, int);
 SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
@@ -9127,7 +10251,6 @@ SQLITE_PRIVATE void sqlite3Vacuum(Parse*);
 SQLITE_PRIVATE int sqlite3RunVacuum(char**, sqlite3*);
 SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3*, Token*);
 SQLITE_PRIVATE int sqlite3ExprCompare(Expr*, Expr*);
-SQLITE_PRIVATE int sqlite3ExprResolveNames(NameContext *, Expr *);
 SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
 SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
 SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse*);
@@ -9140,28 +10263,34 @@ SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse*, int);
 SQLITE_PRIVATE void sqlite3BeginTransaction(Parse*, int);
 SQLITE_PRIVATE void sqlite3CommitTransaction(Parse*);
 SQLITE_PRIVATE void sqlite3RollbackTransaction(Parse*);
+SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
+SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
 SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
 SQLITE_PRIVATE int sqlite3IsRowid(const char*);
-SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int);
+SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int, Trigger *, int);
 SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
 SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
 SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
-                                     int*,int,int,int,int);
-SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*,int,int,int,int);
+                                     int*,int,int,int,int,int*);
+SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*, int, int, int);
 SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
 SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
-SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*);
-SQLITE_PRIVATE void sqlite3TokenCopy(sqlite3*,Token*, Token*);
-SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*);
-SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*);
+SQLITE_PRIVATE void sqlite3MultiWrite(Parse*);
+SQLITE_PRIVATE void sqlite3MayAbort(Parse*);
+SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, char*, int);
+SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
+SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
+SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
 SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3*,IdList*);
-SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3*,Select*);
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3*,Select*,int);
+SQLITE_PRIVATE void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
 SQLITE_PRIVATE FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
 SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(sqlite3*);
-SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(sqlite3*);
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void);
+SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void);
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE   int sqlite3SafetyOn(sqlite3*);
 SQLITE_PRIVATE   int sqlite3SafetyOff(sqlite3*);
@@ -9172,7 +10301,10 @@ SQLITE_PRIVATE   int sqlite3SafetyOff(sqlite3*);
 SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3*);
 SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3*);
 SQLITE_PRIVATE void sqlite3ChangeCookie(Parse*, int);
-SQLITE_PRIVATE void sqlite3MaterializeView(Parse*, Select*, Expr*, int);
+
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
+#endif
 
 #ifndef SQLITE_OMIT_TRIGGER
 SQLITE_PRIVATE   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
@@ -9180,24 +10312,32 @@ SQLITE_PRIVATE   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,
 SQLITE_PRIVATE   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
 SQLITE_PRIVATE   void sqlite3DropTrigger(Parse*, SrcList*, int);
 SQLITE_PRIVATE   void sqlite3DropTriggerPtr(Parse*, Trigger*);
-SQLITE_PRIVATE   int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
-SQLITE_PRIVATE   int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 
-                           int, int, u32*, u32*);
+SQLITE_PRIVATE   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
+SQLITE_PRIVATE   Trigger *sqlite3TriggerList(Parse *, Table *);
+SQLITE_PRIVATE   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
+                            int, int, int);
+SQLITE_PRIVATE   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
-SQLITE_PRIVATE   void sqlite3DeleteTriggerStep(TriggerStep*);
+SQLITE_PRIVATE   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
 SQLITE_PRIVATE   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
 SQLITE_PRIVATE   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
-                                        ExprList*,Select*,int);
-SQLITE_PRIVATE   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
+                                        ExprList*,Select*,u8);
+SQLITE_PRIVATE   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
 SQLITE_PRIVATE   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
-SQLITE_PRIVATE   void sqlite3DeleteTrigger(Trigger*);
+SQLITE_PRIVATE   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
 SQLITE_PRIVATE   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
+SQLITE_PRIVATE   u32 sqlite3TriggerOldmask(Parse*,Trigger*,ExprList*,Table*,int);
+# define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
 #else
-# define sqlite3TriggersExist(A,B,C,D,E,F) 0
-# define sqlite3DeleteTrigger(A)
+# define sqlite3TriggersExist(B,C,D,E,F) 0
+# define sqlite3DeleteTrigger(A,B)
 # define sqlite3DropTriggerPtr(A,B)
 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
-# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J,K) 0
+# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
+# define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
+# define sqlite3TriggerList(X, Y) 0
+# define sqlite3ParseToplevel(p) p
+# define sqlite3TriggerOldmask(A,B,C,D,E) 0
 #endif
 
 SQLITE_PRIVATE int sqlite3JoinType(Parse*, Token*, Token*, Token*);
@@ -9208,6 +10348,7 @@ SQLITE_PRIVATE   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
 SQLITE_PRIVATE   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
 SQLITE_PRIVATE   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
 SQLITE_PRIVATE   void sqlite3AuthContextPop(AuthContext*);
+SQLITE_PRIVATE   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
 #else
 # define sqlite3AuthRead(a,b,c,d)
 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
@@ -9225,12 +10366,11 @@ SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
 SQLITE_PRIVATE int sqlite3FixExprList(DbFixer*, ExprList*);
 SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
 SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*);
-SQLITE_API char *sqlite3_snprintf(int,char*,const char*,...);
 SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
 SQLITE_PRIVATE int sqlite3FitsIn64Bits(const char *, int);
 SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
 SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
-SQLITE_PRIVATE int sqlite3Utf8Read(const u8*, const u8*, const u8**);
+SQLITE_PRIVATE int sqlite3Utf8Read(const u8*, const u8**);
 
 /*
 ** Routines to read and write variable-length integers.  These used to
@@ -9241,8 +10381,8 @@ SQLITE_PRIVATE int sqlite3Utf8Read(const u8*, const u8*, const u8**);
 */
 SQLITE_PRIVATE int sqlite3PutVarint(unsigned char*, u64);
 SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char*, u32);
-SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *, u64 *);
-SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *, u32 *);
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *, u64 *);
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *, u32 *);
 SQLITE_PRIVATE int sqlite3VarintLen(u64 v);
 
 /*
@@ -9262,13 +10402,13 @@ SQLITE_PRIVATE int sqlite3VarintLen(u64 v);
 **     x = putVarint32( A, B );
 **
 */
-#define getVarint32(A,B)  ((*(A)<(unsigned char)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), &(B)))
-#define putVarint32(A,B)  (((B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
+#define getVarint32(A,B)  (u8)((*(A)<(u8)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), (u32 *)&(B)))
+#define putVarint32(A,B)  (u8)(((u32)(B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
 #define getVarint    sqlite3GetVarint
 #define putVarint    sqlite3PutVarint
 
 
-SQLITE_PRIVATE void sqlite3IndexAffinityStr(Vdbe *, Index *);
+SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
 SQLITE_PRIVATE void sqlite3TableAffinityStr(Vdbe *, Table *);
 SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2);
 SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
@@ -9279,8 +10419,8 @@ SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
 SQLITE_PRIVATE int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
 SQLITE_PRIVATE const char *sqlite3ErrStr(int);
 SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse);
-SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char *,int,int);
-SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName);
+SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
+SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
 SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
 SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
 SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
@@ -9294,10 +10434,17 @@ SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
 SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
 SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
 SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int);
+#ifdef SQLITE_ENABLE_STAT2
+SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
+#endif
 SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
 SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
 #ifndef SQLITE_AMALGAMATION
 SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
+SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
+SQLITE_PRIVATE int sqlite3PendingByte;
 #endif
 SQLITE_PRIVATE void sqlite3RootPageMoved(Db*, int, int);
 SQLITE_PRIVATE void sqlite3Reindex(Parse*, Token*, Token*);
@@ -9306,21 +10453,25 @@ SQLITE_PRIVATE void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
 SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *, int *);
 SQLITE_PRIVATE void sqlite3NestedParse(Parse*, const char*, ...);
 SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3*);
-SQLITE_PRIVATE void sqlite3CodeSubselect(Parse *, Expr *);
-SQLITE_PRIVATE int sqlite3SelectResolve(Parse *, Select *, NameContext *);
-SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int);
+SQLITE_PRIVATE void sqlite3CodeSubselect(Parse *, Expr *, int, int);
+SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
+SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
+SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
 SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
 SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
-SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
-SQLITE_PRIVATE char sqlite3AffinityType(const Token*);
+SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(sqlite3*, u8, CollSeq *, const char*);
+SQLITE_PRIVATE char sqlite3AffinityType(const char*);
 SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
 SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
 SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
+SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
 SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index*);
 SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
 SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
 SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
-SQLITE_PRIVATE void sqlite3AttachFunctions(sqlite3 *);
 SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse*, int, int);
 SQLITE_PRIVATE void sqlite3SchemaFree(void *);
 SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
@@ -9332,19 +10483,26 @@ SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
 SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
 SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);
 
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum*, char*, int, int);
 SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum*,const char*,int);
 SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
 SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum*);
 SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
 
+SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *);
+SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
+
 /*
 ** The interface to the LEMON-generated parser
 */
 SQLITE_PRIVATE void *sqlite3ParserAlloc(void*(*)(size_t));
 SQLITE_PRIVATE void sqlite3ParserFree(void*, void(*)(void*));
 SQLITE_PRIVATE void sqlite3Parser(void*, int, Token, Parse*);
+#ifdef YYTRACKMAXSTACKDEPTH
+SQLITE_PRIVATE   int sqlite3ParserStackPeak(void*);
+#endif
 
-SQLITE_PRIVATE int sqlite3AutoLoadExtensions(sqlite3*);
+SQLITE_PRIVATE void sqlite3AutoLoadExtensions(sqlite3*);
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
 SQLITE_PRIVATE   void sqlite3CloseExtensions(sqlite3*);
 #else
@@ -9362,19 +10520,25 @@ SQLITE_PRIVATE   int sqlite3Utf8To8(unsigned char*);
 #endif
 
 #ifdef SQLITE_OMIT_VIRTUALTABLE
-#  define sqlite3VtabClear(X)
-#  define sqlite3VtabSync(X,Y) (Y)
+#  define sqlite3VtabClear(Y)
+#  define sqlite3VtabSync(X,Y) SQLITE_OK
 #  define sqlite3VtabRollback(X)
 #  define sqlite3VtabCommit(X)
+#  define sqlite3VtabInSync(db) 0
+#  define sqlite3VtabLock(X) 
+#  define sqlite3VtabUnlock(X)
+#  define sqlite3VtabUnlockList(X)
 #else
 SQLITE_PRIVATE    void sqlite3VtabClear(Table*);
-SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, int rc);
+SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, char **);
 SQLITE_PRIVATE    int sqlite3VtabRollback(sqlite3 *db);
 SQLITE_PRIVATE    int sqlite3VtabCommit(sqlite3 *db);
+SQLITE_PRIVATE    void sqlite3VtabLock(VTable *);
+SQLITE_PRIVATE    void sqlite3VtabUnlock(VTable *);
+SQLITE_PRIVATE    void sqlite3VtabUnlockList(sqlite3*);
+#  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
 #endif
 SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse*,Table*);
-SQLITE_PRIVATE void sqlite3VtabLock(sqlite3_vtab*);
-SQLITE_PRIVATE void sqlite3VtabUnlock(sqlite3*, sqlite3_vtab*);
 SQLITE_PRIVATE void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*);
 SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse*, Token*);
 SQLITE_PRIVATE void sqlite3VtabArgInit(Parse*);
@@ -9382,12 +10546,42 @@ SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse*, Token*);
 SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
 SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse*, Table*);
 SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
-SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, sqlite3_vtab *);
+SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
 SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
 SQLITE_PRIVATE void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
+SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
 SQLITE_PRIVATE int sqlite3Reprepare(Vdbe*);
 SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
 SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
+SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
+SQLITE_PRIVATE VTable *sqlite3GetVTable(sqlite3*, Table*);
+
+/* Declarations for functions in fkey.c. All of these are replaced by
+** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
+** key functionality is available. If OMIT_TRIGGER is defined but
+** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
+** this case foreign keys are parsed, but no other functionality is 
+** provided (enforcement of FK constraints requires the triggers sub-system).
+*/
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE   void sqlite3FkCheck(Parse*, Table*, int, int);
+SQLITE_PRIVATE   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
+SQLITE_PRIVATE   void sqlite3FkActions(Parse*, Table*, ExprList*, int);
+SQLITE_PRIVATE   int sqlite3FkRequired(Parse*, Table*, int*, int);
+SQLITE_PRIVATE   u32 sqlite3FkOldmask(Parse*, Table*);
+SQLITE_PRIVATE   FKey *sqlite3FkReferences(Table *);
+#else
+  #define sqlite3FkActions(a,b,c,d)
+  #define sqlite3FkCheck(a,b,c,d)
+  #define sqlite3FkDropTable(a,b,c)
+  #define sqlite3FkOldmask(a,b)      0
+  #define sqlite3FkRequired(a,b,c,d) 0
+#endif
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE   void sqlite3FkDelete(Table*);
+#else
+  #define sqlite3FkDelete(a)
+#endif
 
 
 /*
@@ -9397,34 +10591,22 @@ SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
 #define SQLITE_FAULTINJECTOR_COUNT      1
 
 /*
-** The interface to the fault injector subsystem.  If the fault injector
-** mechanism is disabled at compile-time then set up macros so that no
-** unnecessary code is generated.
+** The interface to the code in fault.c used for identifying "benign"
+** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
+** is not defined.
 */
 #ifndef SQLITE_OMIT_BUILTIN_TEST
-SQLITE_PRIVATE   void sqlite3FaultConfig(int,int,int);
-SQLITE_PRIVATE   int sqlite3FaultFailures(int);
-SQLITE_PRIVATE   int sqlite3FaultBenignFailures(int);
-SQLITE_PRIVATE   int sqlite3FaultPending(int);
-SQLITE_PRIVATE   void sqlite3FaultBeginBenign(int);
-SQLITE_PRIVATE   void sqlite3FaultEndBenign(int);
-SQLITE_PRIVATE   int sqlite3FaultStep(int);
+SQLITE_PRIVATE   void sqlite3BeginBenignMalloc(void);
+SQLITE_PRIVATE   void sqlite3EndBenignMalloc(void);
 #else
-# define sqlite3FaultConfig(A,B,C)
-# define sqlite3FaultFailures(A)         0
-# define sqlite3FaultBenignFailures(A)   0
-# define sqlite3FaultPending(A)          (-1)
-# define sqlite3FaultBeginBenign(A)
-# define sqlite3FaultEndBenign(A)
-# define sqlite3FaultStep(A)             0
+  #define sqlite3BeginBenignMalloc()
+  #define sqlite3EndBenignMalloc()
 #endif
-  
-  
 
 #define IN_INDEX_ROWID           1
 #define IN_INDEX_EPH             2
 #define IN_INDEX_INDEX           3
-SQLITE_PRIVATE int sqlite3FindInIndex(Parse *, Expr *, int);
+SQLITE_PRIVATE int sqlite3FindInIndex(Parse *, Expr *, int*);
 
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
 SQLITE_PRIVATE   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
@@ -9434,18 +10616,31 @@ SQLITE_PRIVATE   int sqlite3JournalCreate(sqlite3_file *);
   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
 #endif
 
-#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
-SQLITE_PRIVATE   void sqlite3ExprSetHeight(Expr *);
+SQLITE_PRIVATE void sqlite3MemJournalOpen(sqlite3_file *);
+SQLITE_PRIVATE int sqlite3MemJournalSize(void);
+SQLITE_PRIVATE int sqlite3IsMemJournal(sqlite3_file *);
+
+#if SQLITE_MAX_EXPR_DEPTH>0
+SQLITE_PRIVATE   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
 SQLITE_PRIVATE   int sqlite3SelectExprHeight(Select *);
+SQLITE_PRIVATE   int sqlite3ExprCheckHeight(Parse*, int);
 #else
-  #define sqlite3ExprSetHeight(x)
+  #define sqlite3ExprSetHeight(x,y)
+  #define sqlite3SelectExprHeight(x) 0
+  #define sqlite3ExprCheckHeight(x,y)
 #endif
 
 SQLITE_PRIVATE u32 sqlite3Get4byte(const u8*);
 SQLITE_PRIVATE void sqlite3Put4byte(u8*, u32);
 
-#ifdef SQLITE_SSE
-#include "sseInt.h"
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+SQLITE_PRIVATE   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
+SQLITE_PRIVATE   void sqlite3ConnectionUnlocked(sqlite3 *db);
+SQLITE_PRIVATE   void sqlite3ConnectionClosed(sqlite3 *db);
+#else
+  #define sqlite3ConnectionBlocked(x,y)
+  #define sqlite3ConnectionUnlocked(x)
+  #define sqlite3ConnectionClosed(x)
 #endif
 
 #ifdef SQLITE_DEBUG
@@ -9469,6 +10664,322 @@ SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*,...);
 #endif
 
 /************** End of sqliteInt.h *******************************************/
+/************** Begin file global.c ******************************************/
+/*
+** 2008 June 13
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains definitions of global variables and contants.
+*/
+
+
+/* An array to map all upper-case characters into their corresponding
+** lower-case character. 
+**
+** SQLite only considers US-ASCII (or EBCDIC) characters.  We do not
+** handle case conversions for the UTF character set since the tables
+** involved are nearly as big or bigger than SQLite itself.
+*/
+SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[] = {
+#ifdef SQLITE_ASCII
+      0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17,
+     18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+     36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
+     54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
+    104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
+    122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
+    108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
+    126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
+    144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
+    162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
+    180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
+    198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
+    216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
+    234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
+    252,253,254,255
+#endif
+#ifdef SQLITE_EBCDIC
+      0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, /* 0x */
+     16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, /* 1x */
+     32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, /* 2x */
+     48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, /* 3x */
+     64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, /* 4x */
+     80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, /* 5x */
+     96, 97, 66, 67, 68, 69, 70, 71, 72, 73,106,107,108,109,110,111, /* 6x */
+    112, 81, 82, 83, 84, 85, 86, 87, 88, 89,122,123,124,125,126,127, /* 7x */
+    128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143, /* 8x */
+    144,145,146,147,148,149,150,151,152,153,154,155,156,157,156,159, /* 9x */
+    160,161,162,163,164,165,166,167,168,169,170,171,140,141,142,175, /* Ax */
+    176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191, /* Bx */
+    192,129,130,131,132,133,134,135,136,137,202,203,204,205,206,207, /* Cx */
+    208,145,146,147,148,149,150,151,152,153,218,219,220,221,222,223, /* Dx */
+    224,225,162,163,164,165,166,167,168,169,232,203,204,205,206,207, /* Ex */
+    239,240,241,242,243,244,245,246,247,248,249,219,220,221,222,255, /* Fx */
+#endif
+};
+
+/*
+** The following 256 byte lookup table is used to support SQLites built-in
+** equivalents to the following standard library functions:
+**
+**   isspace()                        0x01
+**   isalpha()                        0x02
+**   isdigit()                        0x04
+**   isalnum()                        0x06
+**   isxdigit()                       0x08
+**   toupper()                        0x20
+**
+** Bit 0x20 is set if the mapped character requires translation to upper
+** case. i.e. if the character is a lower-case ASCII character.
+** If x is a lower-case ASCII character, then its upper-case equivalent
+** is (x - 0x20). Therefore toupper() can be implemented as:
+**
+**   (x & ~(map[x]&0x20))
+**
+** Standard function tolower() is implemented using the sqlite3UpperToLower[]
+** array. tolower() is used more often than toupper() by SQLite.
+**
+** SQLite's versions are identical to the standard versions assuming a
+** locale of "C". They are implemented as macros in sqliteInt.h.
+*/
+#ifdef SQLITE_ASCII
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[256] = {
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 00..07    ........ */
+  0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00,  /* 08..0f    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 10..17    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 18..1f    ........ */
+  0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 20..27     !"#$%&' */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 28..2f    ()*+,-./ */
+  0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,  /* 30..37    01234567 */
+  0x0c, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 38..3f    89:;<=>? */
+
+  0x00, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x02,  /* 40..47    @ABCDEFG */
+  0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,  /* 48..4f    HIJKLMNO */
+  0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,  /* 50..57    PQRSTUVW */
+  0x02, 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 58..5f    XYZ[\]^_ */
+  0x00, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x22,  /* 60..67    `abcdefg */
+  0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,  /* 68..6f    hijklmno */
+  0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,  /* 70..77    pqrstuvw */
+  0x22, 0x22, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 78..7f    xyz{|}~. */
+
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 80..87    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 88..8f    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 90..97    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 98..9f    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* a0..a7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* a8..af    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* b0..b7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* b8..bf    ........ */
+
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* c0..c7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* c8..cf    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* d0..d7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* d8..df    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* e0..e7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* e8..ef    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* f0..f7    ........ */
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00   /* f8..ff    ........ */
+};
+#endif
+
+
+
+/*
+** The following singleton contains the global configuration for
+** the SQLite library.
+*/
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
+   SQLITE_DEFAULT_MEMSTATUS,  /* bMemstat */
+   1,                         /* bCoreMutex */
+   SQLITE_THREADSAFE==1,      /* bFullMutex */
+   0x7ffffffe,                /* mxStrlen */
+   100,                       /* szLookaside */
+   500,                       /* nLookaside */
+   {0,0,0,0,0,0,0,0},         /* m */
+   {0,0,0,0,0,0,0,0,0},       /* mutex */
+   {0,0,0,0,0,0,0,0,0,0,0},   /* pcache */
+   (void*)0,                  /* pHeap */
+   0,                         /* nHeap */
+   0, 0,                      /* mnHeap, mxHeap */
+   (void*)0,                  /* pScratch */
+   0,                         /* szScratch */
+   0,                         /* nScratch */
+   (void*)0,                  /* pPage */
+   0,                         /* szPage */
+   0,                         /* nPage */
+   0,                         /* mxParserStack */
+   0,                         /* sharedCacheEnabled */
+   /* All the rest should always be initialized to zero */
+   0,                         /* isInit */
+   0,                         /* inProgress */
+   0,                         /* isMutexInit */
+   0,                         /* isMallocInit */
+   0,                         /* isPCacheInit */
+   0,                         /* pInitMutex */
+   0,                         /* nRefInitMutex */
+};
+
+
+/*
+** Hash table for global functions - functions common to all
+** database connections.  After initialization, this table is
+** read-only.
+*/
+SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
+
+/*
+** The value of the "pending" byte must be 0x40000000 (1 byte past the
+** 1-gibabyte boundary) in a compatible database.  SQLite never uses
+** the database page that contains the pending byte.  It never attempts
+** to read or write that page.  The pending byte page is set assign
+** for use by the VFS layers as space for managing file locks.
+**
+** During testing, it is often desirable to move the pending byte to
+** a different position in the file.  This allows code that has to
+** deal with the pending byte to run on files that are much smaller
+** than 1 GiB.  The sqlite3_test_control() interface can be used to
+** move the pending byte.
+**
+** IMPORTANT:  Changing the pending byte to any value other than
+** 0x40000000 results in an incompatible database file format!
+** Changing the pending byte during operating results in undefined
+** and dileterious behavior.
+*/
+SQLITE_PRIVATE int sqlite3PendingByte = 0x40000000;
+
+/************** End of global.c **********************************************/
+/************** Begin file status.c ******************************************/
+/*
+** 2008 June 18
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This module implements the sqlite3_status() interface and related
+** functionality.
+**
+** $Id: status.c,v 1.9 2008/09/02 00:52:52 drh Exp $
+*/
+
+/*
+** Variables in which to record status information.
+*/
+typedef struct sqlite3StatType sqlite3StatType;
+static SQLITE_WSD struct sqlite3StatType {
+  int nowValue[9];         /* Current value */
+  int mxValue[9];          /* Maximum value */
+} sqlite3Stat = { {0,}, {0,} };
+
+
+/* The "wsdStat" macro will resolve to the status information
+** state vector.  If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time.  In the more common
+** case where writable static data is supported, wsdStat can refer directly
+** to the "sqlite3Stat" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdStatInit  sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
+# define wsdStat x[0]
+#else
+# define wsdStatInit
+# define wsdStat sqlite3Stat
+#endif
+
+/*
+** Return the current value of a status parameter.
+*/
+SQLITE_PRIVATE int sqlite3StatusValue(int op){
+  wsdStatInit;
+  assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
+  return wsdStat.nowValue[op];
+}
+
+/*
+** Add N to the value of a status record.  It is assumed that the
+** caller holds appropriate locks.
+*/
+SQLITE_PRIVATE void sqlite3StatusAdd(int op, int N){
+  wsdStatInit;
+  assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
+  wsdStat.nowValue[op] += N;
+  if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
+    wsdStat.mxValue[op] = wsdStat.nowValue[op];
+  }
+}
+
+/*
+** Set the value of a status to X.
+*/
+SQLITE_PRIVATE void sqlite3StatusSet(int op, int X){
+  wsdStatInit;
+  assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
+  wsdStat.nowValue[op] = X;
+  if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
+    wsdStat.mxValue[op] = wsdStat.nowValue[op];
+  }
+}
+
+/*
+** Query status information.
+**
+** This implementation assumes that reading or writing an aligned
+** 32-bit integer is an atomic operation.  If that assumption is not true,
+** then this routine is not threadsafe.
+*/
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
+  wsdStatInit;
+  if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
+    return SQLITE_MISUSE;
+  }
+  *pCurrent = wsdStat.nowValue[op];
+  *pHighwater = wsdStat.mxValue[op];
+  if( resetFlag ){
+    wsdStat.mxValue[op] = wsdStat.nowValue[op];
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Query status information for a single database connection
+*/
+SQLITE_API int sqlite3_db_status(
+  sqlite3 *db,          /* The database connection whose status is desired */
+  int op,               /* Status verb */
+  int *pCurrent,        /* Write current value here */
+  int *pHighwater,      /* Write high-water mark here */
+  int resetFlag         /* Reset high-water mark if true */
+){
+  switch( op ){
+    case SQLITE_DBSTATUS_LOOKASIDE_USED: {
+      *pCurrent = db->lookaside.nOut;
+      *pHighwater = db->lookaside.mxOut;
+      if( resetFlag ){
+        db->lookaside.mxOut = db->lookaside.nOut;
+      }
+      break;
+    }
+    default: {
+      return SQLITE_ERROR;
+    }
+  }
+  return SQLITE_OK;
+}
+
+/************** End of status.c **********************************************/
 /************** Begin file date.c ********************************************/
 /*
 ** 2003 October 31
@@ -9488,7 +10999,7 @@ SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*,...);
 ** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
 ** All other code has file scope.
 **
-** $Id: date.c,v 1.79 2008/03/20 14:03:29 drh Exp $
+** $Id: date.c,v 1.107 2009/05/03 20:23:53 drh Exp $
 **
 ** SQLite processes all times and dates as Julian Day numbers.  The
 ** dates and times are stored as the number of days since noon
@@ -9517,25 +11028,41 @@ SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*,...);
 **      Willmann-Bell, Inc
 **      Richmond, Virginia (USA)
 */
-#include <ctype.h>
 #include <time.h>
 
 #ifndef SQLITE_OMIT_DATETIME_FUNCS
 
 /*
+** On recent Windows platforms, the localtime_s() function is available
+** as part of the "Secure CRT". It is essentially equivalent to 
+** localtime_r() available under most POSIX platforms, except that the 
+** order of the parameters is reversed.
+**
+** See http://msdn.microsoft.com/en-us/library/a442x3ye(VS.80).aspx.
+**
+** If the user has not indicated to use localtime_r() or localtime_s()
+** already, check for an MSVC build environment that provides 
+** localtime_s().
+*/
+#if !defined(HAVE_LOCALTIME_R) && !defined(HAVE_LOCALTIME_S) && \
+     defined(_MSC_VER) && defined(_CRT_INSECURE_DEPRECATE)
+#define HAVE_LOCALTIME_S 1
+#endif
+
+/*
 ** A structure for holding a single date and time.
 */
 typedef struct DateTime DateTime;
 struct DateTime {
-  double rJD;      /* The julian day number */
-  int Y, M, D;     /* Year, month, and day */
-  int h, m;        /* Hour and minutes */
-  int tz;          /* Timezone offset in minutes */
-  double s;        /* Seconds */
-  char validYMD;   /* True if Y,M,D are valid */
-  char validHMS;   /* True if h,m,s are valid */
-  char validJD;    /* True if rJD is valid */
-  char validTZ;    /* True if tz is valid */
+  sqlite3_int64 iJD; /* The julian day number times 86400000 */
+  int Y, M, D;       /* Year, month, and day */
+  int h, m;          /* Hour and minutes */
+  int tz;            /* Timezone offset in minutes */
+  double s;          /* Seconds */
+  char validYMD;     /* True (1) if Y,M,D are valid */
+  char validHMS;     /* True (1) if h,m,s are valid */
+  char validJD;      /* True (1) if iJD is valid */
+  char validTZ;      /* True (1) if tz is valid */
 };
 
 
@@ -9570,7 +11097,7 @@ static int getDigits(const char *zDate, ...){
     pVal = va_arg(ap, int*);
     val = 0;
     while( N-- ){
-      if( !isdigit(*(u8*)zDate) ){
+      if( !sqlite3Isdigit(*zDate) ){
         goto end_getDigits;
       }
       val = val*10 + *zDate - '0';
@@ -9614,7 +11141,7 @@ static int parseTimezone(const char *zDate, DateTime *p){
   int sgn = 0;
   int nHr, nMn;
   int c;
-  while( isspace(*(u8*)zDate) ){ zDate++; }
+  while( sqlite3Isspace(*zDate) ){ zDate++; }
   p->tz = 0;
   c = *zDate;
   if( c=='-' ){
@@ -9634,7 +11161,7 @@ static int parseTimezone(const char *zDate, DateTime *p){
   zDate += 5;
   p->tz = sgn*(nMn + nHr*60);
 zulu_time:
-  while( isspace(*(u8*)zDate) ){ zDate++; }
+  while( sqlite3Isspace(*zDate) ){ zDate++; }
   return *zDate!=0;
 }
 
@@ -9658,10 +11185,10 @@ static int parseHhMmSs(const char *zDate, DateTime *p){
       return 1;
     }
     zDate += 2;
-    if( *zDate=='.' && isdigit((u8)zDate[1]) ){
+    if( *zDate=='.' && sqlite3Isdigit(zDate[1]) ){
       double rScale = 1.0;
       zDate++;
-      while( isdigit(*(u8*)zDate) ){
+      while( sqlite3Isdigit(*zDate) ){
         ms = ms*10.0 + *zDate - '0';
         rScale *= 10.0;
         zDate++;
@@ -9677,7 +11204,7 @@ static int parseHhMmSs(const char *zDate, DateTime *p){
   p->m = m;
   p->s = s + ms;
   if( parseTimezone(zDate, p) ) return 1;
-  p->validTZ = p->tz!=0;
+  p->validTZ = (p->tz!=0)?1:0;
   return 0;
 }
 
@@ -9706,14 +11233,14 @@ static void computeJD(DateTime *p){
   }
   A = Y/100;
   B = 2 - A + (A/4);
-  X1 = 365.25*(Y+4716);
-  X2 = 30.6001*(M+1);
-  p->rJD = X1 + X2 + D + B - 1524.5;
+  X1 = 36525*(Y+4716)/100;
+  X2 = 306001*(M+1)/10000;
+  p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
   p->validJD = 1;
   if( p->validHMS ){
-    p->rJD += (p->h*3600.0 + p->m*60.0 + p->s)/86400.0;
+    p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000);
     if( p->validTZ ){
-      p->rJD -= p->tz*60/86400.0;
+      p->iJD -= p->tz*60000;
       p->validYMD = 0;
       p->validHMS = 0;
       p->validTZ = 0;
@@ -9746,7 +11273,7 @@ static int parseYyyyMmDd(const char *zDate, DateTime *p){
     return 1;
   }
   zDate += 10;
-  while( isspace(*(u8*)zDate) || 'T'==*(u8*)zDate ){ zDate++; }
+  while( sqlite3Isspace(*zDate) || 'T'==*(u8*)zDate ){ zDate++; }
   if( parseHhMmSs(zDate, p)==0 ){
     /* We got the time */
   }else if( *zDate==0 ){
@@ -9766,6 +11293,17 @@ static int parseYyyyMmDd(const char *zDate, DateTime *p){
 }
 
 /*
+** Set the time to the current time reported by the VFS
+*/
+static void setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
+  double r;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  sqlite3OsCurrentTime(db->pVfs, &r);
+  p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
+  p->validJD = 1;
+}
+
+/*
 ** Attempt to parse the given string into a Julian Day Number.  Return
 ** the number of errors.
 **
@@ -9786,20 +11324,18 @@ static int parseDateOrTime(
   const char *zDate, 
   DateTime *p
 ){
-  memset(p, 0, sizeof(*p));
+  int isRealNum;    /* Return from sqlite3IsNumber().  Not used */
   if( parseYyyyMmDd(zDate,p)==0 ){
     return 0;
   }else if( parseHhMmSs(zDate, p)==0 ){
     return 0;
   }else if( sqlite3StrICmp(zDate,"now")==0){
-    double r;
-    sqlite3 *db = sqlite3_context_db_handle(context);
-    sqlite3OsCurrentTime(db->pVfs, &r);
-    p->rJD = r;
-    p->validJD = 1;
+    setDateTimeToCurrent(context, p);
     return 0;
-  }else if( sqlite3IsNumber(zDate, 0, SQLITE_UTF8) ){
-    getValue(zDate, &p->rJD);
+  }else if( sqlite3IsNumber(zDate, &isRealNum, SQLITE_UTF8) ){
+    double r;
+    getValue(zDate, &r);
+    p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
     p->validJD = 1;
     return 0;
   }
@@ -9817,14 +11353,14 @@ static void computeYMD(DateTime *p){
     p->M = 1;
     p->D = 1;
   }else{
-    Z = p->rJD + 0.5;
-    A = (Z - 1867216.25)/36524.25;
+    Z = (int)((p->iJD + 43200000)/86400000);
+    A = (int)((Z - 1867216.25)/36524.25);
     A = Z + 1 + A - (A/4);
     B = A + 1524;
-    C = (B - 122.1)/365.25;
-    D = 365.25*C;
-    E = (B-D)/30.6001;
-    X1 = 30.6001*E;
+    C = (int)((B - 122.1)/365.25);
+    D = (36525*C)/100;
+    E = (int)((B-D)/30.6001);
+    X1 = (int)(30.6001*E);
     p->D = B - D - X1;
     p->M = E<14 ? E-1 : E-13;
     p->Y = p->M>2 ? C - 4716 : C - 4715;
@@ -9836,13 +11372,12 @@ static void computeYMD(DateTime *p){
 ** Compute the Hour, Minute, and Seconds from the julian day number.
 */
 static void computeHMS(DateTime *p){
-  int Z, s;
+  int s;
   if( p->validHMS ) return;
   computeJD(p);
-  Z = p->rJD + 0.5;
-  s = (p->rJD + 0.5 - Z)*86400000.0 + 0.5;
-  p->s = 0.001*s;
-  s = p->s;
+  s = (int)((p->iJD + 43200000) % 86400000);
+  p->s = s/1000.0;
+  s = (int)p->s;
   p->s -= s;
   p->h = s/3600;
   s -= p->h*3600;
@@ -9868,21 +11403,13 @@ static void clearYMD_HMS_TZ(DateTime *p){
   p->validTZ = 0;
 }
 
+#ifndef SQLITE_OMIT_LOCALTIME
 /*
-** Windows CE does not declare the localtime
-** function as it is not defined anywhere.
-** Anyway we need the forward-declaration to be
-** able to define it later on.
-*/
-#if defined(_WIN32_WCE) && (_WIN32_WCE >= 0x600)
-struct tm *__cdecl localtime(const time_t *t);
-#endif
-
-/*
-** Compute the difference (in days) between localtime and UTC (a.k.a. GMT)
+** Compute the difference (in milliseconds)
+** between localtime and UTC (a.k.a. GMT)
 ** for the time value p where p is in UTC.
 */
-static double localtimeOffset(DateTime *p){
+static sqlite3_int64 localtimeOffset(DateTime *p){
   DateTime x, y;
   time_t t;
   x = *p;
@@ -9895,13 +11422,13 @@ static double localtimeOffset(DateTime *p){
     x.m = 0;
     x.s = 0.0;
   } else {
-    int s = x.s + 0.5;
+    int s = (int)(x.s + 0.5);
     x.s = s;
   }
   x.tz = 0;
   x.validJD = 0;
   computeJD(&x);
-  t = (x.rJD-2440587.5)*86400.0 + 0.5;
+  t = (time_t)(x.iJD/1000 - 21086676*(i64)10000);
 #ifdef HAVE_LOCALTIME_R
   {
     struct tm sLocal;
@@ -9913,10 +11440,21 @@ static double localtimeOffset(DateTime *p){
     y.m = sLocal.tm_min;
     y.s = sLocal.tm_sec;
   }
+#elif defined(HAVE_LOCALTIME_S) && HAVE_LOCALTIME_S
+  {
+    struct tm sLocal;
+    localtime_s(&sLocal, &t);
+    y.Y = sLocal.tm_year + 1900;
+    y.M = sLocal.tm_mon + 1;
+    y.D = sLocal.tm_mday;
+    y.h = sLocal.tm_hour;
+    y.m = sLocal.tm_min;
+    y.s = sLocal.tm_sec;
+  }
 #else
   {
     struct tm *pTm;
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
+    sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
     pTm = localtime(&t);
     y.Y = pTm->tm_year + 1900;
     y.M = pTm->tm_mon + 1;
@@ -9924,7 +11462,7 @@ static double localtimeOffset(DateTime *p){
     y.h = pTm->tm_hour;
     y.m = pTm->tm_min;
     y.s = pTm->tm_sec;
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
+    sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
   }
 #endif
   y.validYMD = 1;
@@ -9932,8 +11470,9 @@ static double localtimeOffset(DateTime *p){
   y.validJD = 0;
   y.validTZ = 0;
   computeJD(&y);
-  return y.rJD - x.rJD;
+  return y.iJD - x.iJD;
 }
+#endif /* SQLITE_OMIT_LOCALTIME */
 
 /*
 ** Process a modifier to a date-time stamp.  The modifiers are
@@ -9962,11 +11501,12 @@ static int parseModifier(const char *zMod, DateTime *p){
   double r;
   char *z, zBuf[30];
   z = zBuf;
-  for(n=0; n<sizeof(zBuf)-1 && zMod[n]; n++){
-    z[n] = tolower(zMod[n]);
+  for(n=0; n<ArraySize(zBuf)-1 && zMod[n]; n++){
+    z[n] = (char)sqlite3UpperToLower[(u8)zMod[n]];
   }
   z[n] = 0;
   switch( z[0] ){
+#ifndef SQLITE_OMIT_LOCALTIME
     case 'l': {
       /*    localtime
       **
@@ -9975,32 +11515,36 @@ static int parseModifier(const char *zMod, DateTime *p){
       */
       if( strcmp(z, "localtime")==0 ){
         computeJD(p);
-        p->rJD += localtimeOffset(p);
+        p->iJD += localtimeOffset(p);
         clearYMD_HMS_TZ(p);
         rc = 0;
       }
       break;
     }
+#endif
     case 'u': {
       /*
       **    unixepoch
       **
-      ** Treat the current value of p->rJD as the number of
+      ** Treat the current value of p->iJD as the number of
       ** seconds since 1970.  Convert to a real julian day number.
       */
       if( strcmp(z, "unixepoch")==0 && p->validJD ){
-        p->rJD = p->rJD/86400.0 + 2440587.5;
+        p->iJD = (p->iJD + 43200)/86400 + 21086676*(i64)10000000;
         clearYMD_HMS_TZ(p);
         rc = 0;
-      }else if( strcmp(z, "utc")==0 ){
-        double c1;
+      }
+#ifndef SQLITE_OMIT_LOCALTIME
+      else if( strcmp(z, "utc")==0 ){
+        sqlite3_int64 c1;
         computeJD(p);
         c1 = localtimeOffset(p);
-        p->rJD -= c1;
+        p->iJD -= c1;
         clearYMD_HMS_TZ(p);
-        p->rJD += c1 - localtimeOffset(p);
+        p->iJD += c1 - localtimeOffset(p);
         rc = 0;
       }
+#endif
       break;
     }
     case 'w': {
@@ -10012,16 +11556,15 @@ static int parseModifier(const char *zMod, DateTime *p){
       ** date is already on the appropriate weekday, this is a no-op.
       */
       if( strncmp(z, "weekday ", 8)==0 && getValue(&z[8],&r)>0
-                 && (n=r)==r && n>=0 && r<7 ){
-        int Z;
+                 && (n=(int)r)==r && n>=0 && r<7 ){
+        sqlite3_int64 Z;
         computeYMD_HMS(p);
         p->validTZ = 0;
         p->validJD = 0;
         computeJD(p);
-        Z = p->rJD + 1.5;
-        Z %= 7;
+        Z = ((p->iJD + 129600000)/86400000) % 7;
         if( Z>n ) Z -= 7;
-        p->rJD += n - Z;
+        p->iJD += (n - Z)*86400000;
         clearYMD_HMS_TZ(p);
         rc = 0;
       }
@@ -10067,6 +11610,7 @@ static int parseModifier(const char *zMod, DateTime *p){
     case '7':
     case '8':
     case '9': {
+      double rRounder;
       n = getValue(z, &r);
       assert( n>=1 );
       if( z[n]==':' ){
@@ -10077,54 +11621,59 @@ static int parseModifier(const char *zMod, DateTime *p){
         */
         const char *z2 = z;
         DateTime tx;
-        int day;
-        if( !isdigit(*(u8*)z2) ) z2++;
+        sqlite3_int64 day;
+        if( !sqlite3Isdigit(*z2) ) z2++;
         memset(&tx, 0, sizeof(tx));
         if( parseHhMmSs(z2, &tx) ) break;
         computeJD(&tx);
-        tx.rJD -= 0.5;
-        day = (int)tx.rJD;
-        tx.rJD -= day;
-        if( z[0]=='-' ) tx.rJD = -tx.rJD;
+        tx.iJD -= 43200000;
+        day = tx.iJD/86400000;
+        tx.iJD -= day*86400000;
+        if( z[0]=='-' ) tx.iJD = -tx.iJD;
         computeJD(p);
         clearYMD_HMS_TZ(p);
-        p->rJD += tx.rJD;
+        p->iJD += tx.iJD;
         rc = 0;
         break;
       }
       z += n;
-      while( isspace(*(u8*)z) ) z++;
-      n = strlen(z);
+      while( sqlite3Isspace(*z) ) z++;
+      n = sqlite3Strlen30(z);
       if( n>10 || n<3 ) break;
       if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
       computeJD(p);
       rc = 0;
+      rRounder = r<0 ? -0.5 : +0.5;
       if( n==3 && strcmp(z,"day")==0 ){
-        p->rJD += r;
+        p->iJD += (sqlite3_int64)(r*86400000.0 + rRounder);
       }else if( n==4 && strcmp(z,"hour")==0 ){
-        p->rJD += r/24.0;
+        p->iJD += (sqlite3_int64)(r*(86400000.0/24.0) + rRounder);
       }else if( n==6 && strcmp(z,"minute")==0 ){
-        p->rJD += r/(24.0*60.0);
+        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0)) + rRounder);
       }else if( n==6 && strcmp(z,"second")==0 ){
-        p->rJD += r/(24.0*60.0*60.0);
+        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0*60.0)) + rRounder);
       }else if( n==5 && strcmp(z,"month")==0 ){
         int x, y;
         computeYMD_HMS(p);
-        p->M += r;
+        p->M += (int)r;
         x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
         p->Y += x;
         p->M -= x*12;
         p->validJD = 0;
         computeJD(p);
-        y = r;
+        y = (int)r;
         if( y!=r ){
-          p->rJD += (r - y)*30.0;
+          p->iJD += (sqlite3_int64)((r - y)*30.0*86400000.0 + rRounder);
         }
       }else if( n==4 && strcmp(z,"year")==0 ){
+        int y = (int)r;
         computeYMD_HMS(p);
-        p->Y += r;
+        p->Y += y;
         p->validJD = 0;
         computeJD(p);
+        if( y!=r ){
+          p->iJD += (sqlite3_int64)((r - y)*365.0*86400000.0 + rRounder);
+        }
       }else{
         rc = 1;
       }
@@ -10155,14 +11704,19 @@ static int isDate(
 ){
   int i;
   const unsigned char *z;
-  static const unsigned char zDflt[] = "now";
+  int eType;
+  memset(p, 0, sizeof(*p));
   if( argc==0 ){
-    z = zDflt;
+    setDateTimeToCurrent(context, p);
+  }else if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
+                   || eType==SQLITE_INTEGER ){
+    p->iJD = (sqlite3_int64)(sqlite3_value_double(argv[0])*86400000.0 + 0.5);
+    p->validJD = 1;
   }else{
     z = sqlite3_value_text(argv[0]);
-  }
-  if( !z || parseDateOrTime(context, (char*)z, p) ){
-    return 1;
+    if( !z || parseDateOrTime(context, (char*)z, p) ){
+      return 1;
+    }
   }
   for(i=1; i<argc; i++){
     if( (z = sqlite3_value_text(argv[i]))==0 || parseModifier((char*)z, p) ){
@@ -10191,7 +11745,7 @@ static void juliandayFunc(
   DateTime x;
   if( isDate(context, argc, argv, &x)==0 ){
     computeJD(&x);
-    sqlite3_result_double(context, x.rJD);
+    sqlite3_result_double(context, x.iJD/86400000.0);
   }
 }
 
@@ -10279,11 +11833,13 @@ static void strftimeFunc(
 ){
   DateTime x;
   u64 n;
-  int i, j;
+  size_t i,j;
   char *z;
+  sqlite3 *db;
   const char *zFmt = (const char*)sqlite3_value_text(argv[0]);
   char zBuf[100];
   if( zFmt==0 || isDate(context, argc-1, argv+1, &x) ) return;
+  db = sqlite3_context_db_handle(context);
   for(i=0, n=1; zFmt[i]; i++, n++){
     if( zFmt[i]=='%' ){
       switch( zFmt[i+1] ){
@@ -10317,13 +11873,17 @@ static void strftimeFunc(
       i++;
     }
   }
+  testcase( n==sizeof(zBuf)-1 );
+  testcase( n==sizeof(zBuf) );
+  testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
+  testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH] );
   if( n<sizeof(zBuf) ){
     z = zBuf;
-  }else if( n>sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH] ){
+  }else if( n>(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ){
     sqlite3_result_error_toobig(context);
     return;
   }else{
-    z = sqlite3_malloc( n );
+    z = sqlite3DbMallocRaw(db, (int)n);
     if( z==0 ){
       sqlite3_result_error_nomem(context);
       return;
@@ -10342,7 +11902,7 @@ static void strftimeFunc(
           double s = x.s;
           if( s>59.999 ) s = 59.999;
           sqlite3_snprintf(7, &z[j],"%06.3f", s);
-          j += strlen(&z[j]);
+          j += sqlite3Strlen30(&z[j]);
           break;
         }
         case 'H':  sqlite3_snprintf(3, &z[j],"%02d",x.h); j+=2; break;
@@ -10354,10 +11914,10 @@ static void strftimeFunc(
           y.M = 1;
           y.D = 1;
           computeJD(&y);
-          nDay = x.rJD - y.rJD + 0.5;
+          nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
           if( zFmt[i]=='W' ){
             int wd;   /* 0=Monday, 1=Tuesday, ... 6=Sunday */
-            wd = ((int)(x.rJD+0.5)) % 7;
+            wd = (int)(((x.iJD+43200000)/86400000)%7);
             sqlite3_snprintf(3, &z[j],"%02d",(nDay+7-wd)/7);
             j += 2;
           }else{
@@ -10367,28 +11927,34 @@ static void strftimeFunc(
           break;
         }
         case 'J': {
-          sqlite3_snprintf(20, &z[j],"%.16g",x.rJD);
-          j+=strlen(&z[j]);
+          sqlite3_snprintf(20, &z[j],"%.16g",x.iJD/86400000.0);
+          j+=sqlite3Strlen30(&z[j]);
           break;
         }
         case 'm':  sqlite3_snprintf(3, &z[j],"%02d",x.M); j+=2; break;
         case 'M':  sqlite3_snprintf(3, &z[j],"%02d",x.m); j+=2; break;
         case 's': {
-          sqlite3_snprintf(30,&z[j],"%d",
-                           (int)((x.rJD-2440587.5)*86400.0 + 0.5));
-          j += strlen(&z[j]);
+          sqlite3_snprintf(30,&z[j],"%lld",
+                           (i64)(x.iJD/1000 - 21086676*(i64)10000));
+          j += sqlite3Strlen30(&z[j]);
           break;
         }
         case 'S':  sqlite3_snprintf(3,&z[j],"%02d",(int)x.s); j+=2; break;
-        case 'w':  z[j++] = (((int)(x.rJD+1.5)) % 7) + '0'; break;
-        case 'Y':  sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=strlen(&z[j]);break;
+        case 'w': {
+          z[j++] = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
+          break;
+        }
+        case 'Y': {
+          sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=sqlite3Strlen30(&z[j]);
+          break;
+        }
         default:   z[j++] = '%'; break;
       }
     }
   }
   z[j] = 0;
   sqlite3_result_text(context, z, -1,
-                      z==zBuf ? SQLITE_TRANSIENT : sqlite3_free);
+                      z==zBuf ? SQLITE_TRANSIENT : SQLITE_DYNAMIC);
 }
 
 /*
@@ -10398,9 +11964,10 @@ static void strftimeFunc(
 */
 static void ctimeFunc(
   sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+  int NotUsed,
+  sqlite3_value **NotUsed2
 ){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
   timeFunc(context, 0, 0);
 }
 
@@ -10411,9 +11978,10 @@ static void ctimeFunc(
 */
 static void cdateFunc(
   sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+  int NotUsed,
+  sqlite3_value **NotUsed2
 ){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
   dateFunc(context, 0, 0);
 }
 
@@ -10424,9 +11992,10 @@ static void cdateFunc(
 */
 static void ctimestampFunc(
   sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+  int NotUsed,
+  sqlite3_value **NotUsed2
 ){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
   datetimeFunc(context, 0, 0);
 }
 #endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
@@ -10454,9 +12023,19 @@ static void currentTimeFunc(
   double rT;
   char zBuf[20];
 
+  UNUSED_PARAMETER(argc);
+  UNUSED_PARAMETER(argv);
+
   db = sqlite3_context_db_handle(context);
   sqlite3OsCurrentTime(db->pVfs, &rT);
+#ifndef SQLITE_OMIT_FLOATING_POINT
   t = 86400.0*(rT - 2440587.5) + 0.5;
+#else
+  /* without floating point support, rT will have
+  ** already lost fractional day precision.
+  */
+  t = 86400 * (rT - 2440587) - 43200;
+#endif
 #ifdef HAVE_GMTIME_R
   {
     struct tm sNow;
@@ -10466,10 +12045,10 @@ static void currentTimeFunc(
 #else
   {
     struct tm *pTm;
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
+    sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
     pTm = gmtime(&t);
     strftime(zBuf, 20, zFormat, pTm);
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
+    sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
   }
 #endif
 
@@ -10482,44 +12061,30 @@ static void currentTimeFunc(
 ** functions.  This should be the only routine in this file with
 ** external linkage.
 */
-SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(sqlite3 *db){
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void){
+  static SQLITE_WSD FuncDef aDateTimeFuncs[] = {
 #ifndef SQLITE_OMIT_DATETIME_FUNCS
-  static const struct {
-     char *zName;
-     int nArg;
-     void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
-  } aFuncs[] = {
-    { "julianday", -1, juliandayFunc   },
-    { "date",      -1, dateFunc        },
-    { "time",      -1, timeFunc        },
-    { "datetime",  -1, datetimeFunc    },
-    { "strftime",  -1, strftimeFunc    },
-    { "current_time",       0, ctimeFunc      },
-    { "current_timestamp",  0, ctimestampFunc },
-    { "current_date",       0, cdateFunc      },
-  };
-  int i;
-
-  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
-    sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
-        SQLITE_UTF8, 0, aFuncs[i].xFunc, 0, 0);
-  }
+    FUNCTION(julianday,        -1, 0, 0, juliandayFunc ),
+    FUNCTION(date,             -1, 0, 0, dateFunc      ),
+    FUNCTION(time,             -1, 0, 0, timeFunc      ),
+    FUNCTION(datetime,         -1, 0, 0, datetimeFunc  ),
+    FUNCTION(strftime,         -1, 0, 0, strftimeFunc  ),
+    FUNCTION(current_time,      0, 0, 0, ctimeFunc     ),
+    FUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
+    FUNCTION(current_date,      0, 0, 0, cdateFunc     ),
 #else
-  static const struct {
-     char *zName;
-     char *zFormat;
-  } aFuncs[] = {
-    { "current_time", "%H:%M:%S" },
-    { "current_date", "%Y-%m-%d" },
-    { "current_timestamp", "%Y-%m-%d %H:%M:%S" }
+    STR_FUNCTION(current_time,      0, "%H:%M:%S",          0, currentTimeFunc),
+    STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d",          0, currentTimeFunc),
+    STR_FUNCTION(current_date,      0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
+#endif
   };
   int i;
+  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aDateTimeFuncs);
 
-  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
-    sqlite3CreateFunc(db, aFuncs[i].zName, 0, SQLITE_UTF8, 
-        aFuncs[i].zFormat, currentTimeFunc, 0, 0);
+  for(i=0; i<ArraySize(aDateTimeFuncs); i++){
+    sqlite3FuncDefInsert(pHash, &aFunc[i]);
   }
-#endif
 }
 
 /************** End of date.c ************************************************/
@@ -10538,6 +12103,8 @@ SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(sqlite3 *db){
 **
 ** This file contains OS interface code that is common to all
 ** architectures.
+**
+** $Id: os.c,v 1.127 2009/07/27 11:41:21 danielk1977 Exp $
 */
 #define _SQLITE_OS_C_ 1
 #undef _SQLITE_OS_C_
@@ -10559,14 +12126,14 @@ SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(sqlite3 *db){
 **     sqlite3OsLock()
 **
 */
-#if defined(SQLITE_TEST) && (OS_WIN==0)
-  #define DO_OS_MALLOC_TEST if (1) {            \
-    void *pTstAlloc = sqlite3_malloc(10);       \
-    if (!pTstAlloc) return SQLITE_IOERR_NOMEM;  \
-    sqlite3_free(pTstAlloc);                    \
+#if defined(SQLITE_TEST) && (SQLITE_OS_WIN==0)
+  #define DO_OS_MALLOC_TEST(x) if (!x || !sqlite3IsMemJournal(x)) {     \
+    void *pTstAlloc = sqlite3Malloc(10);                             \
+    if (!pTstAlloc) return SQLITE_IOERR_NOMEM;                       \
+    sqlite3_free(pTstAlloc);                                         \
   }
 #else
-  #define DO_OS_MALLOC_TEST
+  #define DO_OS_MALLOC_TEST(x)
 #endif
 
 /*
@@ -10584,35 +12151,37 @@ SQLITE_PRIVATE int sqlite3OsClose(sqlite3_file *pId){
   return rc;
 }
 SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file *id, void *pBuf, int amt, i64 offset){
-  DO_OS_MALLOC_TEST;
+  DO_OS_MALLOC_TEST(id);
   return id->pMethods->xRead(id, pBuf, amt, offset);
 }
 SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file *id, const void *pBuf, int amt, i64 offset){
-  DO_OS_MALLOC_TEST;
+  DO_OS_MALLOC_TEST(id);
   return id->pMethods->xWrite(id, pBuf, amt, offset);
 }
 SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file *id, i64 size){
   return id->pMethods->xTruncate(id, size);
 }
 SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file *id, int flags){
-  DO_OS_MALLOC_TEST;
+  DO_OS_MALLOC_TEST(id);
   return id->pMethods->xSync(id, flags);
 }
 SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
+  DO_OS_MALLOC_TEST(id);
   return id->pMethods->xFileSize(id, pSize);
 }
 SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file *id, int lockType){
-  DO_OS_MALLOC_TEST;
+  DO_OS_MALLOC_TEST(id);
   return id->pMethods->xLock(id, lockType);
 }
 SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file *id, int lockType){
   return id->pMethods->xUnlock(id, lockType);
 }
-SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id){
-  return id->pMethods->xCheckReservedLock(id);
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut){
+  DO_OS_MALLOC_TEST(id);
+  return id->pMethods->xCheckReservedLock(id, pResOut);
 }
 SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file *id, int op, void *pArg){
-  return id->pMethods->xFileControl(id,op,pArg);
+  return id->pMethods->xFileControl(id, op, pArg);
 }
 SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id){
   int (*xSectorSize)(sqlite3_file*) = id->pMethods->xSectorSize;
@@ -10633,24 +12202,27 @@ SQLITE_PRIVATE int sqlite3OsOpen(
   int flags, 
   int *pFlagsOut
 ){
-  DO_OS_MALLOC_TEST;
-  return pVfs->xOpen(pVfs, zPath, pFile, flags, pFlagsOut);
+  int rc;
+  DO_OS_MALLOC_TEST(0);
+  /* 0x7f1f is a mask of SQLITE_OPEN_ flags that are valid to be passed
+  ** down into the VFS layer.  Some SQLITE_OPEN_ flags (for example,
+  ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
+  ** reaching the VFS. */
+  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x7f1f, pFlagsOut);
+  assert( rc==SQLITE_OK || pFile->pMethods==0 );
+  return rc;
 }
 SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
   return pVfs->xDelete(pVfs, zPath, dirSync);
 }
-SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
-  int rc;
-#ifdef SQLITE_TEST
-  void *pTstAlloc = sqlite3_malloc(10);
-  if (!pTstAlloc) return -1;
-  sqlite3_free(pTstAlloc);
-#endif
-  rc = pVfs->xAccess(pVfs, zPath, flags);
-  return rc;
-}
-SQLITE_PRIVATE int sqlite3OsGetTempname(sqlite3_vfs *pVfs, int nBufOut, char *zBufOut){
-  return pVfs->xGetTempname(pVfs, nBufOut, zBufOut);
+SQLITE_PRIVATE int sqlite3OsAccess(
+  sqlite3_vfs *pVfs, 
+  const char *zPath, 
+  int flags, 
+  int *pResOut
+){
+  DO_OS_MALLOC_TEST(0);
+  return pVfs->xAccess(pVfs, zPath, flags, pResOut);
 }
 SQLITE_PRIVATE int sqlite3OsFullPathname(
   sqlite3_vfs *pVfs, 
@@ -10660,18 +12232,20 @@ SQLITE_PRIVATE int sqlite3OsFullPathname(
 ){
   return pVfs->xFullPathname(pVfs, zPath, nPathOut, zPathOut);
 }
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
 SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
   return pVfs->xDlOpen(pVfs, zPath);
 }
 SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
   pVfs->xDlError(pVfs, nByte, zBufOut);
 }
-SQLITE_PRIVATE void *sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
-  return pVfs->xDlSym(pVfs, pHandle, zSymbol);
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHdle, const char *zSym))(void){
+  return pVfs->xDlSym(pVfs, pHdle, zSym);
 }
 SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
   pVfs->xDlClose(pVfs, pHandle);
 }
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
 SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
   return pVfs->xRandomness(pVfs, nByte, zBufOut);
 }
@@ -10691,7 +12265,7 @@ SQLITE_PRIVATE int sqlite3OsOpenMalloc(
 ){
   int rc = SQLITE_NOMEM;
   sqlite3_file *pFile;
-  pFile = (sqlite3_file *)sqlite3_malloc(pVfs->szOsFile);
+  pFile = (sqlite3_file *)sqlite3Malloc(pVfs->szOsFile);
   if( pFile ){
     rc = sqlite3OsOpen(pVfs, zFile, pFile, flags, pOutFlags);
     if( rc!=SQLITE_OK ){
@@ -10711,27 +12285,41 @@ SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *pFile){
 }
 
 /*
-** The list of all registered VFS implementations.  This list is
-** initialized to the single VFS returned by sqlite3OsDefaultVfs()
-** upon the first call to sqlite3_vfs_find().
+** This function is a wrapper around the OS specific implementation of
+** sqlite3_os_init(). The purpose of the wrapper is to provide the
+** ability to simulate a malloc failure, so that the handling of an
+** error in sqlite3_os_init() by the upper layers can be tested.
 */
-static sqlite3_vfs *vfsList = 0;
+SQLITE_PRIVATE int sqlite3OsInit(void){
+  void *p = sqlite3_malloc(10);
+  if( p==0 ) return SQLITE_NOMEM;
+  sqlite3_free(p);
+  return sqlite3_os_init();
+}
+
+/*
+** The list of all registered VFS implementations.
+*/
+static sqlite3_vfs * SQLITE_WSD vfsList = 0;
+#define vfsList GLOBAL(sqlite3_vfs *, vfsList)
 
 /*
 ** Locate a VFS by name.  If no name is given, simply return the
 ** first VFS on the list.
 */
 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-#endif
   sqlite3_vfs *pVfs = 0;
-  static int isInit = 0;
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex;
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+  int rc = sqlite3_initialize();
+  if( rc ) return 0;
+#endif
+#if SQLITE_THREADSAFE
+  mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
   sqlite3_mutex_enter(mutex);
-  if( !isInit ){
-    vfsList = sqlite3OsDefaultVfs();
-    isInit = 1;
-  }
   for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
     if( zVfs==0 ) break;
     if( strcmp(zVfs, pVfs->zName)==0 ) break;
@@ -10744,7 +12332,7 @@ SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
 ** Unlink a VFS from the linked list
 */
 static void vfsUnlink(sqlite3_vfs *pVfs){
-  assert( sqlite3_mutex_held(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER)) );
+  assert( sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)) );
   if( pVfs==0 ){
     /* No-op */
   }else if( vfsList==pVfs ){
@@ -10766,10 +12354,12 @@ static void vfsUnlink(sqlite3_vfs *pVfs){
 ** true.
 */
 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
+  sqlite3_mutex *mutex = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+  int rc = sqlite3_initialize();
+  if( rc ) return rc;
 #endif
-  sqlite3_vfs_find(0);  /* Make sure we are initialized */
+  mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
   sqlite3_mutex_enter(mutex);
   vfsUnlink(pVfs);
   if( makeDflt || vfsList==0 ){
@@ -10788,8 +12378,8 @@ SQLITE_API int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
 ** Unregister a VFS so that it is no longer accessible.
 */
 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
 #endif
   sqlite3_mutex_enter(mutex);
   vfsUnlink(pVfs);
@@ -10797,14 +12387,6 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
   return SQLITE_OK;
 }
 
-/*
-** Provide a default sqlite3OsDefaultVfs() implementation in the
-** cases where none of the standard backends are used.
-*/
-#if !OS_UNIX && !OS_WIN && !OS_OS2
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){ return 0; }
-#endif
-
 /************** End of os.c **************************************************/
 /************** Begin file fault.c *******************************************/
 /*
@@ -10818,161 +12400,150 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){ return 0; }
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains code to implement a fault-injector used for
-** testing and verification of SQLite.
 **
-** Subsystems within SQLite can call sqlite3FaultStep() to see if
-** they should simulate a fault.  sqlite3FaultStep() normally returns
-** zero but will return non-zero if a fault should be simulated.
-** Fault injectors can be used, for example, to simulate memory
-** allocation failures or I/O errors.
+** $Id: fault.c,v 1.11 2008/09/02 00:52:52 drh Exp $
+*/
+
+/*
+** This file contains code to support the concept of "benign" 
+** malloc failures (when the xMalloc() or xRealloc() method of the
+** sqlite3_mem_methods structure fails to allocate a block of memory
+** and returns 0). 
 **
-** The fault injector is omitted from the code if SQLite is
-** compiled with -DSQLITE_OMIT_BUILTIN_TEST=1.  There is a very
-** small performance hit for leaving the fault injector in the code.
-** Commerical products will probably want to omit the fault injector
-** from production builds.  But safety-critical systems who work
-** under the motto "fly what you test and test what you fly" may
-** choose to leave the fault injector enabled even in production.
+** Most malloc failures are non-benign. After they occur, SQLite
+** abandons the current operation and returns an error code (usually
+** SQLITE_NOMEM) to the user. However, sometimes a fault is not necessarily
+** fatal. For example, if a malloc fails while resizing a hash table, this 
+** is completely recoverable simply by not carrying out the resize. The 
+** hash table will continue to function normally.  So a malloc failure 
+** during a hash table resize is a benign fault.
 */
 
+
 #ifndef SQLITE_OMIT_BUILTIN_TEST
 
 /*
-** There can be various kinds of faults.  For example, there can be
-** a memory allocation failure.  Or an I/O failure.  For each different
-** fault type, there is a separate FaultInjector structure to keep track
-** of the status of that fault.
+** Global variables.
 */
-static struct FaultInjector {
-  int iCountdown;   /* Number of pending successes before we hit a failure */
-  int nRepeat;      /* Number of times to repeat the failure */
-  int nBenign;      /* Number of benign failures seen since last config */
-  int nFail;        /* Number of failures seen since last config */
-  u8 enable;        /* True if enabled */
-  i16 benign;       /* Positive if next failure will be benign */
-} aFault[SQLITE_FAULTINJECTOR_COUNT];
+typedef struct BenignMallocHooks BenignMallocHooks;
+static SQLITE_WSD struct BenignMallocHooks {
+  void (*xBenignBegin)(void);
+  void (*xBenignEnd)(void);
+} sqlite3Hooks = { 0, 0 };
 
-/*
-** This routine configures and enables a fault injector.  After
-** calling this routine, aFaultStep() will return false (zero)
-** nDelay times, then it will return true nRepeat times,
-** then it will again begin returning false.
+/* The "wsdHooks" macro will resolve to the appropriate BenignMallocHooks
+** structure.  If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time.  In the more common
+** case where writable static data is supported, wsdHooks can refer directly
+** to the "sqlite3Hooks" state vector declared above.
 */
-SQLITE_PRIVATE void sqlite3FaultConfig(int id, int nDelay, int nRepeat){
-  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-  aFault[id].iCountdown = nDelay;
-  aFault[id].nRepeat = nRepeat;
-  aFault[id].nBenign = 0;
-  aFault[id].nFail = 0;
-  aFault[id].enable = nDelay>=0;
-  aFault[id].benign = 0;
-}
+#ifdef SQLITE_OMIT_WSD
+# define wsdHooksInit \
+  BenignMallocHooks *x = &GLOBAL(BenignMallocHooks,sqlite3Hooks)
+# define wsdHooks x[0]
+#else
+# define wsdHooksInit
+# define wsdHooks sqlite3Hooks
+#endif
 
-/*
-** Return the number of faults (both hard and benign faults) that have
-** occurred since the injector was last configured.
-*/
-SQLITE_PRIVATE int sqlite3FaultFailures(int id){
-  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-  return aFault[id].nFail;
-}
 
 /*
-** Return the number of benign faults that have occurred since the
-** injector was last configured.
+** Register hooks to call when sqlite3BeginBenignMalloc() and
+** sqlite3EndBenignMalloc() are called, respectively.
 */
-SQLITE_PRIVATE int sqlite3FaultBenignFailures(int id){
-  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-  return aFault[id].nBenign;
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(
+  void (*xBenignBegin)(void),
+  void (*xBenignEnd)(void)
+){
+  wsdHooksInit;
+  wsdHooks.xBenignBegin = xBenignBegin;
+  wsdHooks.xBenignEnd = xBenignEnd;
 }
 
 /*
-** Return the number of successes that will occur before the next failure.
-** If no failures are scheduled, return -1.
+** This (sqlite3EndBenignMalloc()) is called by SQLite code to indicate that
+** subsequent malloc failures are benign. A call to sqlite3EndBenignMalloc()
+** indicates that subsequent malloc failures are non-benign.
 */
-SQLITE_PRIVATE int sqlite3FaultPending(int id){
-  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-  if( aFault[id].enable ){
-    return aFault[id].iCountdown;
-  }else{
-    return -1;
-  }
-}
-
-/* 
-** After this routine causes subsequent faults to be either benign
-** or hard (not benign), according to the "enable" parameter.
-**
-** Most faults are hard.  In other words, most faults cause
-** an error to be propagated back up to the application interface.
-** However, sometimes a fault is easily recoverable.  For example,
-** if a malloc fails while resizing a hash table, this is completely
-** recoverable simply by not carrying out the resize.  The hash table
-** will continue to function normally.  So a malloc failure during
-** a hash table resize is a benign fault.  
-*/
-SQLITE_PRIVATE void sqlite3FaultBeginBenign(int id){
-  if( id<0 ){
-    for(id=0; id<SQLITE_FAULTINJECTOR_COUNT; id++){
-      aFault[id].benign++;
-    }
-  }else{
-    assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-    aFault[id].benign++;
+SQLITE_PRIVATE void sqlite3BeginBenignMalloc(void){
+  wsdHooksInit;
+  if( wsdHooks.xBenignBegin ){
+    wsdHooks.xBenignBegin();
   }
 }
-SQLITE_PRIVATE void sqlite3FaultEndBenign(int id){
-  if( id<0 ){
-    for(id=0; id<SQLITE_FAULTINJECTOR_COUNT; id++){
-      assert( aFault[id].benign>0 );
-      aFault[id].benign--;
-    }
-  }else{
-    assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-    assert( aFault[id].benign>0 );
-    aFault[id].benign--;
+SQLITE_PRIVATE void sqlite3EndBenignMalloc(void){
+  wsdHooksInit;
+  if( wsdHooks.xBenignEnd ){
+    wsdHooks.xBenignEnd();
   }
 }
 
+#endif   /* #ifndef SQLITE_OMIT_BUILTIN_TEST */
+
+/************** End of fault.c ***********************************************/
+/************** Begin file mem0.c ********************************************/
 /*
-** This routine exists as a place to set a breakpoint that will
-** fire on any simulated fault.
+** 2008 October 28
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains a no-op memory allocation drivers for use when
+** SQLITE_ZERO_MALLOC is defined.  The allocation drivers implemented
+** here always fail.  SQLite will not operate with these drivers.  These
+** are merely placeholders.  Real drivers must be substituted using
+** sqlite3_config() before SQLite will operate.
+**
+** $Id: mem0.c,v 1.1 2008/10/28 18:58:20 drh Exp $
 */
-static void sqlite3Fault(void){
-  static int cnt = 0;
-  cnt++;
-}
 
+/*
+** This version of the memory allocator is the default.  It is
+** used when no other memory allocator is specified using compile-time
+** macros.
+*/
+#ifdef SQLITE_ZERO_MALLOC
 
 /*
-** Check to see if a fault should be simulated.  Return true to simulate
-** the fault.  Return false if the fault should not be simulated.
+** No-op versions of all memory allocation routines
 */
-SQLITE_PRIVATE int sqlite3FaultStep(int id){
-  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
-  if( likely(!aFault[id].enable) ){
-    return 0;
-  }
-  if( aFault[id].iCountdown>0 ){
-    aFault[id].iCountdown--;
-    return 0;
-  }
-  sqlite3Fault();
-  aFault[id].nFail++;
-  if( aFault[id].benign>0 ){
-    aFault[id].nBenign++;
-  }
-  aFault[id].nRepeat--;
-  if( aFault[id].nRepeat<=0 ){
-    aFault[id].enable = 0;
-  }
-  return 1;  
+static void *sqlite3MemMalloc(int nByte){ return 0; }
+static void sqlite3MemFree(void *pPrior){ return; }
+static void *sqlite3MemRealloc(void *pPrior, int nByte){ return 0; }
+static int sqlite3MemSize(void *pPrior){ return 0; }
+static int sqlite3MemRoundup(int n){ return n; }
+static int sqlite3MemInit(void *NotUsed){ return SQLITE_OK; }
+static void sqlite3MemShutdown(void *NotUsed){ return; }
+
+/*
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+  static const sqlite3_mem_methods defaultMethods = {
+     sqlite3MemMalloc,
+     sqlite3MemFree,
+     sqlite3MemRealloc,
+     sqlite3MemSize,
+     sqlite3MemRoundup,
+     sqlite3MemInit,
+     sqlite3MemShutdown,
+     0
+  };
+  sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
 }
 
-#endif /* SQLITE_OMIT_BUILTIN_TEST */
+#endif /* SQLITE_ZERO_MALLOC */
 
-/************** End of fault.c ***********************************************/
+/************** End of mem0.c ************************************************/
 /************** Begin file mem1.c ********************************************/
 /*
 ** 2007 August 14
@@ -10985,10 +12556,15 @@ SQLITE_PRIVATE int sqlite3FaultStep(int id){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains the C functions that implement a memory
-** allocation subsystem for use by SQLite.  
 **
-** $Id: mem1.c,v 1.17 2008/03/18 00:07:11 drh Exp $
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object.
+**
+** $Id: mem1.c,v 1.30 2009/03/23 04:33:33 danielk1977 Exp $
 */
 
 /*
@@ -10999,212 +12575,117 @@ SQLITE_PRIVATE int sqlite3FaultStep(int id){
 #ifdef SQLITE_SYSTEM_MALLOC
 
 /*
-** All of the static variables used by this module are collected
-** into a single structure named "mem".  This is to keep the
-** static variables organized and to reduce namespace pollution
-** when this module is combined with other in the amalgamation.
-*/
-static struct {
-  /*
-  ** The alarm callback and its arguments.  The mem.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.  The alarmBusy variable is set to prevent recursive
-  ** callbacks.
-  */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64,int);
-  void *alarmArg;
-  int alarmBusy;
-  
-  /*
-  ** Mutex to control access to the memory allocation subsystem.
-  */
-  sqlite3_mutex *mutex;
-  
-  /*
-  ** Current allocation and high-water mark.
-  */
-  sqlite3_int64 nowUsed;
-  sqlite3_int64 mxUsed;
-  
- 
-} mem;
-
-/*
-** Enter the mutex mem.mutex. Allocate it if it is not already allocated.
+** Like malloc(), but remember the size of the allocation
+** so that we can find it later using sqlite3MemSize().
+**
+** For this low-level routine, we are guaranteed that nByte>0 because
+** cases of nByte<=0 will be intercepted and dealt with by higher level
+** routines.
 */
-static void enterMem(void){
-  if( mem.mutex==0 ){
-    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
+static void *sqlite3MemMalloc(int nByte){
+  sqlite3_int64 *p;
+  assert( nByte>0 );
+  nByte = ROUND8(nByte);
+  p = malloc( nByte+8 );
+  if( p ){
+    p[0] = nByte;
+    p++;
   }
-  sqlite3_mutex_enter(mem.mutex);
+  return (void *)p;
 }
 
 /*
-** Return the amount of memory currently checked out.
+** Like free() but works for allocations obtained from sqlite3MemMalloc()
+** or sqlite3MemRealloc().
+**
+** For this low-level routine, we already know that pPrior!=0 since
+** cases where pPrior==0 will have been intecepted and dealt with
+** by higher-level routines.
 */
-SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
-  sqlite3_int64 n;
-  enterMem();
-  n = mem.nowUsed;
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
+static void sqlite3MemFree(void *pPrior){
+  sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+  assert( pPrior!=0 );
+  p--;
+  free(p);
 }
 
 /*
-** Return the maximum amount of memory that has ever been
-** checked out since either the beginning of this process
-** or since the most recent reset.
+** Like realloc().  Resize an allocation previously obtained from
+** sqlite3MemMalloc().
+**
+** For this low-level interface, we know that pPrior!=0.  Cases where
+** pPrior==0 while have been intercepted by higher-level routine and
+** redirected to xMalloc.  Similarly, we know that nByte>0 becauses
+** cases where nByte<=0 will have been intercepted by higher-level
+** routines and redirected to xFree.
 */
-SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
-  sqlite3_int64 n;
-  enterMem();
-  n = mem.mxUsed;
-  if( resetFlag ){
-    mem.mxUsed = mem.nowUsed;
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
+  sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+  assert( pPrior!=0 && nByte>0 );
+  nByte = ROUND8(nByte);
+  p = (sqlite3_int64*)pPrior;
+  p--;
+  p = realloc(p, nByte+8 );
+  if( p ){
+    p[0] = nByte;
+    p++;
   }
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
-}
-
-/*
-** Change the alarm callback
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  enterMem();
-  mem.alarmCallback = xCallback;
-  mem.alarmArg = pArg;
-  mem.alarmThreshold = iThreshold;
-  sqlite3_mutex_leave(mem.mutex);
-  return SQLITE_OK;
+  return (void*)p;
 }
 
 /*
-** Trigger the alarm 
+** Report the allocated size of a prior return from xMalloc()
+** or xRealloc().
 */
-static void sqlite3MemsysAlarm(int nByte){
-  void (*xCallback)(void*,sqlite3_int64,int);
-  sqlite3_int64 nowUsed;
-  void *pArg;
-  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
-  mem.alarmBusy = 1;
-  xCallback = mem.alarmCallback;
-  nowUsed = mem.nowUsed;
-  pArg = mem.alarmArg;
-  sqlite3_mutex_leave(mem.mutex);
-  xCallback(pArg, nowUsed, nByte);
-  sqlite3_mutex_enter(mem.mutex);
-  mem.alarmBusy = 0;
+static int sqlite3MemSize(void *pPrior){
+  sqlite3_int64 *p;
+  if( pPrior==0 ) return 0;
+  p = (sqlite3_int64*)pPrior;
+  p--;
+  return (int)p[0];
 }
 
 /*
-** Allocate nBytes of memory
+** Round up a request size to the next valid allocation size.
 */
-SQLITE_API void *sqlite3_malloc(int nBytes){
-  sqlite3_int64 *p = 0;
-  if( nBytes>0 ){
-    enterMem();
-    if( mem.alarmCallback!=0 && mem.nowUsed+nBytes>=mem.alarmThreshold ){
-      sqlite3MemsysAlarm(nBytes);
-    }
-    if( sqlite3FaultStep(SQLITE_FAULTINJECTOR_MALLOC) ){
-      p = 0;
-    }else{
-      p = malloc(nBytes+8);
-      if( p==0 ){
-        sqlite3MemsysAlarm(nBytes);
-        p = malloc(nBytes+8);
-      }
-    }
-    if( p ){
-      p[0] = nBytes;
-      p++;
-      mem.nowUsed += nBytes;
-      if( mem.nowUsed>mem.mxUsed ){
-        mem.mxUsed = mem.nowUsed;
-      }
-    }
-    sqlite3_mutex_leave(mem.mutex);
-  }
-  return (void*)p; 
+static int sqlite3MemRoundup(int n){
+  return ROUND8(n);
 }
 
 /*
-** Free memory.
+** Initialize this module.
 */
-SQLITE_API void sqlite3_free(void *pPrior){
-  sqlite3_int64 *p;
-  int nByte;
-  if( pPrior==0 ){
-    return;
-  }
-  assert( mem.mutex!=0 );
-  p = pPrior;
-  p--;
-  nByte = (int)*p;
-  sqlite3_mutex_enter(mem.mutex);
-  mem.nowUsed -= nByte;
-  free(p);
-  sqlite3_mutex_leave(mem.mutex);  
+static int sqlite3MemInit(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  return SQLITE_OK;
 }
 
 /*
-** Return the number of bytes allocated at p.
+** Deinitialize this module.
 */
-SQLITE_PRIVATE int sqlite3MallocSize(void *p){
-  sqlite3_int64 *pInt;
-  if( !p ) return 0;
-  pInt = p;
-  return pInt[-1];
+static void sqlite3MemShutdown(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  return;
 }
 
 /*
-** Change the size of an existing memory allocation
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
 */
-SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
-  int nOld;
-  sqlite3_int64 *p;
-  if( pPrior==0 ){
-    return sqlite3_malloc(nBytes);
-  }
-  if( nBytes<=0 ){
-    sqlite3_free(pPrior);
-    return 0;
-  }
-  p = pPrior;
-  p--;
-  nOld = (int)p[0];
-  assert( mem.mutex!=0 );
-  sqlite3_mutex_enter(mem.mutex);
-  if( mem.nowUsed+nBytes-nOld>=mem.alarmThreshold ){
-    sqlite3MemsysAlarm(nBytes-nOld);
-  }
-  if( sqlite3FaultStep(SQLITE_FAULTINJECTOR_MALLOC) ){
-    p = 0;
-  }else{
-    p = realloc(p, nBytes+8);
-    if( p==0 ){
-      sqlite3MemsysAlarm(nBytes);
-      p = pPrior;
-      p--;
-      p = realloc(p, nBytes+8);
-    }
-  }
-  if( p ){
-    p[0] = nBytes;
-    p++;
-    mem.nowUsed += nBytes-nOld;
-    if( mem.nowUsed>mem.mxUsed ){
-      mem.mxUsed = mem.nowUsed;
-    }
-  }
-  sqlite3_mutex_leave(mem.mutex);
-  return (void*)p;
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+  static const sqlite3_mem_methods defaultMethods = {
+     sqlite3MemMalloc,
+     sqlite3MemFree,
+     sqlite3MemRealloc,
+     sqlite3MemSize,
+     sqlite3MemRoundup,
+     sqlite3MemInit,
+     sqlite3MemShutdown,
+     0
+  };
+  sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
 }
 
 #endif /* SQLITE_SYSTEM_MALLOC */
@@ -11222,10 +12703,17 @@ SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains the C functions that implement a memory
-** allocation subsystem for use by SQLite.  
 **
-** $Id: mem2.c,v 1.26 2008/04/10 14:57:25 drh Exp $
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs while adding lots of additional debugging
+** information to each allocation in order to help detect and fix memory
+** leaks and memory usage errors.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object.
+**
+** $Id: mem2.c,v 1.45 2009/03/23 04:33:33 danielk1977 Exp $
 */
 
 /*
@@ -11241,7 +12729,7 @@ SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
   extern int backtrace(void**,int);
   extern void backtrace_symbols_fd(void*const*,int,int);
 #else
-# define backtrace(A,B) 0
+# define backtrace(A,B) 1
 # define backtrace_symbols_fd(A,B,C)
 #endif
 
@@ -11285,29 +12773,12 @@ struct MemBlockHdr {
 ** when this module is combined with other in the amalgamation.
 */
 static struct {
-  /*
-  ** The alarm callback and its arguments.  The mem.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.  The alarmBusy variable is set to prevent recursive
-  ** callbacks.
-  */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64, int);
-  void *alarmArg;
-  int alarmBusy;
   
   /*
   ** Mutex to control access to the memory allocation subsystem.
   */
   sqlite3_mutex *mutex;
-  
-  /*
-  ** Current allocation and high-water mark.
-  */
-  sqlite3_int64 nowUsed;
-  sqlite3_int64 mxUsed;
-  
+
   /*
   ** Head and tail of a linked list of all outstanding allocations
   */
@@ -11334,84 +12805,35 @@ static struct {
 
   /*
   ** Gather statistics on the sizes of memory allocations.
-  ** sizeCnt[i] is the number of allocation attempts of i*8
+  ** nAlloc[i] is the number of allocation attempts of i*8
   ** bytes.  i==NCSIZE is the number of allocation attempts for
   ** sizes more than NCSIZE*8 bytes.
   */
-  int sizeCnt[NCSIZE];
+  int nAlloc[NCSIZE];      /* Total number of allocations */
+  int nCurrent[NCSIZE];    /* Current number of allocations */
+  int mxCurrent[NCSIZE];   /* Highwater mark for nCurrent */
 
 } mem;
 
 
 /*
-** Enter the mutex mem.mutex. Allocate it if it is not already allocated.
+** Adjust memory usage statistics
 */
-static void enterMem(void){
-  if( mem.mutex==0 ){
-    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
+static void adjustStats(int iSize, int increment){
+  int i = ROUND8(iSize)/8;
+  if( i>NCSIZE-1 ){
+    i = NCSIZE - 1;
   }
-  sqlite3_mutex_enter(mem.mutex);
-}
-
-/*
-** Return the amount of memory currently checked out.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
-  sqlite3_int64 n;
-  enterMem();
-  n = mem.nowUsed;
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
-}
-
-/*
-** Return the maximum amount of memory that has ever been
-** checked out since either the beginning of this process
-** or since the most recent reset.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
-  sqlite3_int64 n;
-  enterMem();
-  n = mem.mxUsed;
-  if( resetFlag ){
-    mem.mxUsed = mem.nowUsed;
+  if( increment>0 ){
+    mem.nAlloc[i]++;
+    mem.nCurrent[i]++;
+    if( mem.nCurrent[i]>mem.mxCurrent[i] ){
+      mem.mxCurrent[i] = mem.nCurrent[i];
+    }
+  }else{
+    mem.nCurrent[i]--;
+    assert( mem.nCurrent[i]>=0 );
   }
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
-}
-
-/*
-** Change the alarm callback
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used, int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  enterMem();
-  mem.alarmCallback = xCallback;
-  mem.alarmArg = pArg;
-  mem.alarmThreshold = iThreshold;
-  sqlite3_mutex_leave(mem.mutex);
-  return SQLITE_OK;
-}
-
-/*
-** Trigger the alarm 
-*/
-static void sqlite3MemsysAlarm(int nByte){
-  void (*xCallback)(void*,sqlite3_int64,int);
-  sqlite3_int64 nowUsed;
-  void *pArg;
-  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
-  mem.alarmBusy = 1;
-  xCallback = mem.alarmCallback;
-  nowUsed = mem.nowUsed;
-  pArg = mem.alarmArg;
-  sqlite3_mutex_leave(mem.mutex);
-  xCallback(pArg, nowUsed, nByte);
-  sqlite3_mutex_enter(mem.mutex);
-  mem.alarmBusy = 0;
 }
 
 /*
@@ -11428,21 +12850,23 @@ static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){
 
   p = (struct MemBlockHdr*)pAllocation;
   p--;
-  assert( p->iForeGuard==FOREGUARD );
-  nReserve = (p->iSize+7)&~7;
+  assert( p->iForeGuard==(int)FOREGUARD );
+  nReserve = ROUND8(p->iSize);
   pInt = (int*)pAllocation;
   pU8 = (u8*)pAllocation;
-  assert( pInt[nReserve/sizeof(int)]==REARGUARD );
-  assert( (nReserve-0)<=p->iSize || pU8[nReserve-1]==0x65 );
-  assert( (nReserve-1)<=p->iSize || pU8[nReserve-2]==0x65 );
-  assert( (nReserve-2)<=p->iSize || pU8[nReserve-3]==0x65 );
+  assert( pInt[nReserve/sizeof(int)]==(int)REARGUARD );
+  /* This checks any of the "extra" bytes allocated due
+  ** to rounding up to an 8 byte boundary to ensure 
+  ** they haven't been overwritten.
+  */
+  while( nReserve-- > p->iSize ) assert( pU8[nReserve]==0x65 );
   return p;
 }
 
 /*
 ** Return the number of bytes currently allocated at address p.
 */
-SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+static int sqlite3MemSize(void *p){
   struct MemBlockHdr *pHdr;
   if( !p ){
     return 0;
@@ -11452,99 +12876,103 @@ SQLITE_PRIVATE int sqlite3MallocSize(void *p){
 }
 
 /*
+** Initialize the memory allocation subsystem.
+*/
+static int sqlite3MemInit(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  assert( (sizeof(struct MemBlockHdr)&7) == 0 );
+  if( !sqlite3GlobalConfig.bMemstat ){
+    /* If memory status is enabled, then the malloc.c wrapper will already
+    ** hold the STATIC_MEM mutex when the routines here are invoked. */
+    mem.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+static void sqlite3MemShutdown(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  mem.mutex = 0;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int sqlite3MemRoundup(int n){
+  return ROUND8(n);
+}
+
+/*
 ** Allocate nByte bytes of memory.
 */
-SQLITE_API void *sqlite3_malloc(int nByte){
+static void *sqlite3MemMalloc(int nByte){
   struct MemBlockHdr *pHdr;
   void **pBt;
   char *z;
   int *pInt;
   void *p = 0;
   int totalSize;
-
-  if( nByte>0 ){
-    int nReserve;
-    enterMem();
-    assert( mem.disallow==0 );
-    if( mem.alarmCallback!=0 && mem.nowUsed+nByte>=mem.alarmThreshold ){
-      sqlite3MemsysAlarm(nByte);
-    }
-    nReserve = (nByte+7)&~7;
-    if( nReserve/8>NCSIZE-1 ){
-      mem.sizeCnt[NCSIZE-1]++;
-    }else{
-      mem.sizeCnt[nReserve/8]++;
-    }
-    totalSize = nReserve + sizeof(*pHdr) + sizeof(int) +
-                 mem.nBacktrace*sizeof(void*) + mem.nTitle;
-    if( sqlite3FaultStep(SQLITE_FAULTINJECTOR_MALLOC) ){
-      p = 0;
+  int nReserve;
+  sqlite3_mutex_enter(mem.mutex);
+  assert( mem.disallow==0 );
+  nReserve = ROUND8(nByte);
+  totalSize = nReserve + sizeof(*pHdr) + sizeof(int) +
+               mem.nBacktrace*sizeof(void*) + mem.nTitle;
+  p = malloc(totalSize);
+  if( p ){
+    z = p;
+    pBt = (void**)&z[mem.nTitle];
+    pHdr = (struct MemBlockHdr*)&pBt[mem.nBacktrace];
+    pHdr->pNext = 0;
+    pHdr->pPrev = mem.pLast;
+    if( mem.pLast ){
+      mem.pLast->pNext = pHdr;
     }else{
-      p = malloc(totalSize);
-      if( p==0 ){
-        sqlite3MemsysAlarm(nByte);
-        p = malloc(totalSize);
+      mem.pFirst = pHdr;
+    }
+    mem.pLast = pHdr;
+    pHdr->iForeGuard = FOREGUARD;
+    pHdr->nBacktraceSlots = mem.nBacktrace;
+    pHdr->nTitle = mem.nTitle;
+    if( mem.nBacktrace ){
+      void *aAddr[40];
+      pHdr->nBacktrace = backtrace(aAddr, mem.nBacktrace+1)-1;
+      memcpy(pBt, &aAddr[1], pHdr->nBacktrace*sizeof(void*));
+      assert(pBt[0]);
+      if( mem.xBacktrace ){
+        mem.xBacktrace(nByte, pHdr->nBacktrace-1, &aAddr[1]);
       }
+    }else{
+      pHdr->nBacktrace = 0;
     }
-    if( p ){
-      z = p;
-      pBt = (void**)&z[mem.nTitle];
-      pHdr = (struct MemBlockHdr*)&pBt[mem.nBacktrace];
-      pHdr->pNext = 0;
-      pHdr->pPrev = mem.pLast;
-      if( mem.pLast ){
-        mem.pLast->pNext = pHdr;
-      }else{
-        mem.pFirst = pHdr;
-      }
-      mem.pLast = pHdr;
-      pHdr->iForeGuard = FOREGUARD;
-      pHdr->nBacktraceSlots = mem.nBacktrace;
-      pHdr->nTitle = mem.nTitle;
-      if( mem.nBacktrace ){
-        void *aAddr[40];
-        pHdr->nBacktrace = backtrace(aAddr, mem.nBacktrace+1)-1;
-        memcpy(pBt, &aAddr[1], pHdr->nBacktrace*sizeof(void*));
-	if( mem.xBacktrace ){
-          mem.xBacktrace(nByte, pHdr->nBacktrace-1, &aAddr[1]);
-	}
-      }else{
-        pHdr->nBacktrace = 0;
-      }
-      if( mem.nTitle ){
-        memcpy(z, mem.zTitle, mem.nTitle);
-      }
-      pHdr->iSize = nByte;
-      pInt = (int*)&pHdr[1];
-      pInt[nReserve/sizeof(int)] = REARGUARD;
-      memset(pInt, 0x65, nReserve);
-      mem.nowUsed += nByte;
-      if( mem.nowUsed>mem.mxUsed ){
-        mem.mxUsed = mem.nowUsed;
-      }
-      p = (void*)pInt;
+    if( mem.nTitle ){
+      memcpy(z, mem.zTitle, mem.nTitle);
     }
-    sqlite3_mutex_leave(mem.mutex);
+    pHdr->iSize = nByte;
+    adjustStats(nByte, +1);
+    pInt = (int*)&pHdr[1];
+    pInt[nReserve/sizeof(int)] = REARGUARD;
+    memset(pInt, 0x65, nReserve);
+    p = (void*)pInt;
   }
+  sqlite3_mutex_leave(mem.mutex);
   return p; 
 }
 
 /*
 ** Free memory.
 */
-SQLITE_API void sqlite3_free(void *pPrior){
+static void sqlite3MemFree(void *pPrior){
   struct MemBlockHdr *pHdr;
   void **pBt;
   char *z;
-  if( pPrior==0 ){
-    return;
-  }
-  assert( mem.mutex!=0 );
+  assert( sqlite3GlobalConfig.bMemstat || mem.mutex!=0 );
   pHdr = sqlite3MemsysGetHeader(pPrior);
   pBt = (void**)pHdr;
   pBt -= pHdr->nBacktraceSlots;
   sqlite3_mutex_enter(mem.mutex);
-  mem.nowUsed -= pHdr->iSize;
   if( pHdr->pPrev ){
     assert( pHdr->pPrev->pNext==pHdr );
     pHdr->pPrev->pNext = pHdr->pNext;
@@ -11561,6 +12989,7 @@ SQLITE_API void sqlite3_free(void *pPrior){
   }
   z = (char*)pBt;
   z -= pHdr->nTitle;
+  adjustStats(pHdr->iSize, -1);
   memset(z, 0x2b, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
                   pHdr->iSize + sizeof(int) + pHdr->nTitle);
   free(z);
@@ -11576,32 +13005,43 @@ SQLITE_API void sqlite3_free(void *pPrior){
 ** much more likely to break and we are much more liking to find
 ** the error.
 */
-SQLITE_API void *sqlite3_realloc(void *pPrior, int nByte){
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
   struct MemBlockHdr *pOldHdr;
   void *pNew;
-  if( pPrior==0 ){
-    return sqlite3_malloc(nByte);
-  }
-  if( nByte<=0 ){
-    sqlite3_free(pPrior);
-    return 0;
-  }
   assert( mem.disallow==0 );
   pOldHdr = sqlite3MemsysGetHeader(pPrior);
-  pNew = sqlite3_malloc(nByte);
+  pNew = sqlite3MemMalloc(nByte);
   if( pNew ){
     memcpy(pNew, pPrior, nByte<pOldHdr->iSize ? nByte : pOldHdr->iSize);
     if( nByte>pOldHdr->iSize ){
       memset(&((char*)pNew)[pOldHdr->iSize], 0x2b, nByte - pOldHdr->iSize);
     }
-    sqlite3_free(pPrior);
+    sqlite3MemFree(pPrior);
   }
   return pNew;
 }
 
 /*
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+  static const sqlite3_mem_methods defaultMethods = {
+     sqlite3MemMalloc,
+     sqlite3MemFree,
+     sqlite3MemRealloc,
+     sqlite3MemSize,
+     sqlite3MemRoundup,
+     sqlite3MemInit,
+     sqlite3MemShutdown,
+     0
+  };
+  sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+/*
 ** Set the number of backtrace levels kept for each allocation.
-** A value of zero turns of backtracing.  The number is always rounded
+** A value of zero turns off backtracing.  The number is always rounded
 ** up to a multiple of 2.
 */
 SQLITE_PRIVATE void sqlite3MemdebugBacktrace(int depth){
@@ -11619,12 +13059,12 @@ SQLITE_PRIVATE void sqlite3MemdebugBacktraceCallback(void (*xBacktrace)(int, int
 ** Set the title string for subsequent allocations.
 */
 SQLITE_PRIVATE void sqlite3MemdebugSettitle(const char *zTitle){
-  int n = strlen(zTitle) + 1;
-  enterMem();
+  unsigned int n = sqlite3Strlen30(zTitle) + 1;
+  sqlite3_mutex_enter(mem.mutex);
   if( n>=sizeof(mem.zTitle) ) n = sizeof(mem.zTitle)-1;
   memcpy(mem.zTitle, zTitle, n);
   mem.zTitle[n] = 0;
-  mem.nTitle = (n+7)&~7;
+  mem.nTitle = ROUND8(n);
   sqlite3_mutex_leave(mem.mutex);
 }
 
@@ -11667,24 +13107,27 @@ SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
   }
   fprintf(out, "COUNTS:\n");
   for(i=0; i<NCSIZE-1; i++){
-    if( mem.sizeCnt[i] ){
-      fprintf(out, "   %3d: %d\n", i*8+8, mem.sizeCnt[i]);
+    if( mem.nAlloc[i] ){
+      fprintf(out, "   %5d: %10d %10d %10d\n", 
+            i*8, mem.nAlloc[i], mem.nCurrent[i], mem.mxCurrent[i]);
     }
   }
-  if( mem.sizeCnt[NCSIZE-1] ){
-    fprintf(out, "  >%3d: %d\n", NCSIZE*8, mem.sizeCnt[NCSIZE-1]);
+  if( mem.nAlloc[NCSIZE-1] ){
+    fprintf(out, "   %5d: %10d %10d %10d\n",
+             NCSIZE*8-8, mem.nAlloc[NCSIZE-1],
+             mem.nCurrent[NCSIZE-1], mem.mxCurrent[NCSIZE-1]);
   }
   fclose(out);
 }
 
 /*
-** Return the number of times sqlite3_malloc() has been called.
+** Return the number of times sqlite3MemMalloc() has been called.
 */
 SQLITE_PRIVATE int sqlite3MemdebugMallocCount(){
   int i;
   int nTotal = 0;
   for(i=0; i<NCSIZE; i++){
-    nTotal += mem.sizeCnt[i];
+    nTotal += mem.nAlloc[i];
   }
   return nTotal;
 }
@@ -11709,21 +13152,27 @@ SQLITE_PRIVATE int sqlite3MemdebugMallocCount(){
 ** allocation subsystem for use by SQLite. 
 **
 ** This version of the memory allocation subsystem omits all
-** use of malloc().  All dynamically allocatable memory is
-** contained in a static array, mem.aPool[].  The size of this
-** fixed memory pool is SQLITE_MEMORY_SIZE bytes.
+** use of malloc(). The SQLite user supplies a block of memory
+** before calling sqlite3_initialize() from which allocations
+** are made and returned by the xMalloc() and xRealloc() 
+** implementations. Once sqlite3_initialize() has been called,
+** the amount of memory available to SQLite is fixed and cannot
+** be changed.
 **
-** This version of the memory allocation subsystem is used if
-** and only if SQLITE_MEMORY_SIZE is defined.
+** This version of the memory allocation subsystem is included
+** in the build only if SQLITE_ENABLE_MEMSYS3 is defined.
 **
-** $Id: mem3.c,v 1.12 2008/02/19 15:15:16 drh Exp $
+** $Id: mem3.c,v 1.25 2008/11/19 16:52:44 danielk1977 Exp $
 */
 
 /*
-** This version of the memory allocator is used only when 
-** SQLITE_MEMORY_SIZE is defined.
+** This version of the memory allocator is only built into the library
+** SQLITE_ENABLE_MEMSYS3 is defined. Defining this symbol does not
+** mean that the library will use a memory-pool by default, just that
+** it is available. The mempool allocator is activated by calling
+** sqlite3_config().
 */
-#ifdef SQLITE_MEMORY_SIZE
+#ifdef SQLITE_ENABLE_MEMSYS3
 
 /*
 ** Maximum size (in Mem3Blocks) of a "small" chunk.
@@ -11753,7 +13202,7 @@ SQLITE_PRIVATE int sqlite3MemdebugMallocCount(){
 ** u.hdr.prevSize can be part of the data for that chunk and should
 ** not be read or written.
 **
-** We often identify a chunk by its index in mem.aPool[].  When
+** We often identify a chunk by its index in mem3.aPool[].  When
 ** this is done, the chunk index refers to the second block of
 ** the chunk.  In this way, the first chunk has an index of 1.
 ** A chunk index of 0 means "no such chunk" and is the equivalent
@@ -11761,8 +13210,8 @@ SQLITE_PRIVATE int sqlite3MemdebugMallocCount(){
 **
 ** The second block of free chunks is of the form u.list.  The
 ** two fields form a double-linked list of chunks of related sizes.
-** Pointers to the head of the list are stored in mem.aiSmall[] 
-** for smaller chunks and mem.aiHash[] for larger chunks.
+** Pointers to the head of the list are stored in mem3.aiSmall[] 
+** for smaller chunks and mem3.aiHash[] for larger chunks.
 **
 ** The second block of a chunk is user data if the chunk is checked 
 ** out.  If a chunk is checked out, the user data may extend into
@@ -11776,19 +13225,26 @@ struct Mem3Block {
       u32 size4x;     /* 4x the size of current chunk in Mem3Block elements */
     } hdr;
     struct {
-      u32 next;       /* Index in mem.aPool[] of next free chunk */
-      u32 prev;       /* Index in mem.aPool[] of previous free chunk */
+      u32 next;       /* Index in mem3.aPool[] of next free chunk */
+      u32 prev;       /* Index in mem3.aPool[] of previous free chunk */
     } list;
   } u;
 };
 
 /*
 ** All of the static variables used by this module are collected
-** into a single structure named "mem".  This is to keep the
+** into a single structure named "mem3".  This is to keep the
 ** static variables organized and to reduce namespace pollution
 ** when this module is combined with other in the amalgamation.
 */
-static struct {
+static SQLITE_WSD struct Mem3Global {
+  /*
+  ** Memory available for allocation. nPool is the size of the array
+  ** (in Mem3Blocks) pointed to by aPool less 2.
+  */
+  u32 nPool;
+  Mem3Block *aPool;
+
   /*
   ** True if we are evaluating an out-of-memory callback.
   */
@@ -11820,31 +13276,28 @@ static struct {
   */
   u32 aiSmall[MX_SMALL-1];   /* For sizes 2 through MX_SMALL, inclusive */
   u32 aiHash[N_HASH];        /* For sizes MX_SMALL+1 and larger */
+} mem3 = { 97535575 };
 
-  /*
-  ** Memory available for allocation
-  */
-  Mem3Block aPool[SQLITE_MEMORY_SIZE/sizeof(Mem3Block)+2];
-} mem;
+#define mem3 GLOBAL(struct Mem3Global, mem3)
 
 /*
-** Unlink the chunk at mem.aPool[i] from list it is currently
+** Unlink the chunk at mem3.aPool[i] from list it is currently
 ** on.  *pRoot is the list that i is a member of.
 */
 static void memsys3UnlinkFromList(u32 i, u32 *pRoot){
-  u32 next = mem.aPool[i].u.list.next;
-  u32 prev = mem.aPool[i].u.list.prev;
-  assert( sqlite3_mutex_held(mem.mutex) );
+  u32 next = mem3.aPool[i].u.list.next;
+  u32 prev = mem3.aPool[i].u.list.prev;
+  assert( sqlite3_mutex_held(mem3.mutex) );
   if( prev==0 ){
     *pRoot = next;
   }else{
-    mem.aPool[prev].u.list.next = next;
+    mem3.aPool[prev].u.list.next = next;
   }
   if( next ){
-    mem.aPool[next].u.list.prev = prev;
+    mem3.aPool[next].u.list.prev = prev;
   }
-  mem.aPool[i].u.list.next = 0;
-  mem.aPool[i].u.list.prev = 0;
+  mem3.aPool[i].u.list.next = 0;
+  mem3.aPool[i].u.list.prev = 0;
 }
 
 /*
@@ -11853,30 +13306,30 @@ static void memsys3UnlinkFromList(u32 i, u32 *pRoot){
 */
 static void memsys3Unlink(u32 i){
   u32 size, hash;
-  assert( sqlite3_mutex_held(mem.mutex) );
-  assert( (mem.aPool[i-1].u.hdr.size4x & 1)==0 );
+  assert( sqlite3_mutex_held(mem3.mutex) );
+  assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
   assert( i>=1 );
-  size = mem.aPool[i-1].u.hdr.size4x/4;
-  assert( size==mem.aPool[i+size-1].u.hdr.prevSize );
+  size = mem3.aPool[i-1].u.hdr.size4x/4;
+  assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
   assert( size>=2 );
   if( size <= MX_SMALL ){
-    memsys3UnlinkFromList(i, &mem.aiSmall[size-2]);
+    memsys3UnlinkFromList(i, &mem3.aiSmall[size-2]);
   }else{
     hash = size % N_HASH;
-    memsys3UnlinkFromList(i, &mem.aiHash[hash]);
+    memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
   }
 }
 
 /*
-** Link the chunk at mem.aPool[i] so that is on the list rooted
+** Link the chunk at mem3.aPool[i] so that is on the list rooted
 ** at *pRoot.
 */
 static void memsys3LinkIntoList(u32 i, u32 *pRoot){
-  assert( sqlite3_mutex_held(mem.mutex) );
-  mem.aPool[i].u.list.next = *pRoot;
-  mem.aPool[i].u.list.prev = 0;
+  assert( sqlite3_mutex_held(mem3.mutex) );
+  mem3.aPool[i].u.list.next = *pRoot;
+  mem3.aPool[i].u.list.prev = 0;
   if( *pRoot ){
-    mem.aPool[*pRoot].u.list.prev = i;
+    mem3.aPool[*pRoot].u.list.prev = i;
   }
   *pRoot = i;
 }
@@ -11887,174 +13340,113 @@ static void memsys3LinkIntoList(u32 i, u32 *pRoot){
 */
 static void memsys3Link(u32 i){
   u32 size, hash;
-  assert( sqlite3_mutex_held(mem.mutex) );
+  assert( sqlite3_mutex_held(mem3.mutex) );
   assert( i>=1 );
-  assert( (mem.aPool[i-1].u.hdr.size4x & 1)==0 );
-  size = mem.aPool[i-1].u.hdr.size4x/4;
-  assert( size==mem.aPool[i+size-1].u.hdr.prevSize );
+  assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
+  size = mem3.aPool[i-1].u.hdr.size4x/4;
+  assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
   assert( size>=2 );
   if( size <= MX_SMALL ){
-    memsys3LinkIntoList(i, &mem.aiSmall[size-2]);
+    memsys3LinkIntoList(i, &mem3.aiSmall[size-2]);
   }else{
     hash = size % N_HASH;
-    memsys3LinkIntoList(i, &mem.aiHash[hash]);
+    memsys3LinkIntoList(i, &mem3.aiHash[hash]);
   }
 }
 
 /*
-** Enter the mutex mem.mutex. Allocate it if it is not already allocated.
-**
-** Also:  Initialize the memory allocation subsystem the first time
-** this routine is called.
+** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
+** will already be held (obtained by code in malloc.c) if
+** sqlite3GlobalConfig.bMemStat is true.
 */
 static void memsys3Enter(void){
-  if( mem.mutex==0 ){
-    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
-    mem.aPool[0].u.hdr.size4x = SQLITE_MEMORY_SIZE/2 + 2;
-    mem.aPool[SQLITE_MEMORY_SIZE/8].u.hdr.prevSize = SQLITE_MEMORY_SIZE/8;
-    mem.aPool[SQLITE_MEMORY_SIZE/8].u.hdr.size4x = 1;
-    mem.iMaster = 1;
-    mem.szMaster = SQLITE_MEMORY_SIZE/8;
-    mem.mnMaster = mem.szMaster;
-  }
-  sqlite3_mutex_enter(mem.mutex);
-}
-
-/*
-** Return the amount of memory currently checked out.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
-  sqlite3_int64 n;
-  memsys3Enter();
-  n = SQLITE_MEMORY_SIZE - mem.szMaster*8;
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
-}
-
-/*
-** Return the maximum amount of memory that has ever been
-** checked out since either the beginning of this process
-** or since the most recent reset.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
-  sqlite3_int64 n;
-  memsys3Enter();
-  n = SQLITE_MEMORY_SIZE - mem.mnMaster*8;
-  if( resetFlag ){
-    mem.mnMaster = mem.szMaster;
+  if( sqlite3GlobalConfig.bMemstat==0 && mem3.mutex==0 ){
+    mem3.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
   }
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
+  sqlite3_mutex_enter(mem3.mutex);
 }
-
-/*
-** Change the alarm callback.
-**
-** This is a no-op for the static memory allocator.  The purpose
-** of the memory alarm is to support sqlite3_soft_heap_limit().
-** But with this memory allocator, the soft_heap_limit is really
-** a hard limit that is fixed at SQLITE_MEMORY_SIZE.
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  return SQLITE_OK;
+static void memsys3Leave(void){
+  sqlite3_mutex_leave(mem3.mutex);
 }
 
 /*
 ** Called when we are unable to satisfy an allocation of nBytes.
 */
 static void memsys3OutOfMemory(int nByte){
-  if( !mem.alarmBusy ){
-    mem.alarmBusy = 1;
-    assert( sqlite3_mutex_held(mem.mutex) );
-    sqlite3_mutex_leave(mem.mutex);
+  if( !mem3.alarmBusy ){
+    mem3.alarmBusy = 1;
+    assert( sqlite3_mutex_held(mem3.mutex) );
+    sqlite3_mutex_leave(mem3.mutex);
     sqlite3_release_memory(nByte);
-    sqlite3_mutex_enter(mem.mutex);
-    mem.alarmBusy = 0;
+    sqlite3_mutex_enter(mem3.mutex);
+    mem3.alarmBusy = 0;
   }
 }
 
-/*
-** Return the size of an outstanding allocation, in bytes.  The
-** size returned omits the 8-byte header overhead.  This only
-** works for chunks that are currently checked out.
-*/
-SQLITE_PRIVATE int sqlite3MallocSize(void *p){
-  int iSize = 0;
-  if( p ){
-    Mem3Block *pBlock = (Mem3Block*)p;
-    assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
-    iSize = (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
-  }
-  return iSize;
-}
 
 /*
 ** Chunk i is a free chunk that has been unlinked.  Adjust its 
 ** size parameters for check-out and return a pointer to the 
 ** user portion of the chunk.
 */
-static void *memsys3Checkout(u32 i, int nBlock){
+static void *memsys3Checkout(u32 i, u32 nBlock){
   u32 x;
-  assert( sqlite3_mutex_held(mem.mutex) );
+  assert( sqlite3_mutex_held(mem3.mutex) );
   assert( i>=1 );
-  assert( mem.aPool[i-1].u.hdr.size4x/4==nBlock );
-  assert( mem.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
-  x = mem.aPool[i-1].u.hdr.size4x;
-  mem.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
-  mem.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
-  mem.aPool[i+nBlock-1].u.hdr.size4x |= 2;
-  return &mem.aPool[i];
+  assert( mem3.aPool[i-1].u.hdr.size4x/4==nBlock );
+  assert( mem3.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
+  x = mem3.aPool[i-1].u.hdr.size4x;
+  mem3.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
+  mem3.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
+  mem3.aPool[i+nBlock-1].u.hdr.size4x |= 2;
+  return &mem3.aPool[i];
 }
 
 /*
-** Carve a piece off of the end of the mem.iMaster free chunk.
+** Carve a piece off of the end of the mem3.iMaster free chunk.
 ** Return a pointer to the new allocation.  Or, if the master chunk
 ** is not large enough, return 0.
 */
-static void *memsys3FromMaster(int nBlock){
-  assert( sqlite3_mutex_held(mem.mutex) );
-  assert( mem.szMaster>=nBlock );
-  if( nBlock>=mem.szMaster-1 ){
+static void *memsys3FromMaster(u32 nBlock){
+  assert( sqlite3_mutex_held(mem3.mutex) );
+  assert( mem3.szMaster>=nBlock );
+  if( nBlock>=mem3.szMaster-1 ){
     /* Use the entire master */
-    void *p = memsys3Checkout(mem.iMaster, mem.szMaster);
-    mem.iMaster = 0;
-    mem.szMaster = 0;
-    mem.mnMaster = 0;
+    void *p = memsys3Checkout(mem3.iMaster, mem3.szMaster);
+    mem3.iMaster = 0;
+    mem3.szMaster = 0;
+    mem3.mnMaster = 0;
     return p;
   }else{
     /* Split the master block.  Return the tail. */
     u32 newi, x;
-    newi = mem.iMaster + mem.szMaster - nBlock;
-    assert( newi > mem.iMaster+1 );
-    mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = nBlock;
-    mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x |= 2;
-    mem.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
-    mem.szMaster -= nBlock;
-    mem.aPool[newi-1].u.hdr.prevSize = mem.szMaster;
-    x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
-    mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
-    if( mem.szMaster < mem.mnMaster ){
-      mem.mnMaster = mem.szMaster;
+    newi = mem3.iMaster + mem3.szMaster - nBlock;
+    assert( newi > mem3.iMaster+1 );
+    mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = nBlock;
+    mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x |= 2;
+    mem3.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
+    mem3.szMaster -= nBlock;
+    mem3.aPool[newi-1].u.hdr.prevSize = mem3.szMaster;
+    x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+    mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+    if( mem3.szMaster < mem3.mnMaster ){
+      mem3.mnMaster = mem3.szMaster;
     }
-    return (void*)&mem.aPool[newi];
+    return (void*)&mem3.aPool[newi];
   }
 }
 
 /*
 ** *pRoot is the head of a list of free chunks of the same size
 ** or same size hash.  In other words, *pRoot is an entry in either
-** mem.aiSmall[] or mem.aiHash[].  
+** mem3.aiSmall[] or mem3.aiHash[].  
 **
 ** This routine examines all entries on the given list and tries
 ** to coalesce each entries with adjacent free chunks.  
 **
-** If it sees a chunk that is larger than mem.iMaster, it replaces 
-** the current mem.iMaster with the new larger chunk.  In order for
-** this mem.iMaster replacement to work, the master chunk must be
+** If it sees a chunk that is larger than mem3.iMaster, it replaces 
+** the current mem3.iMaster with the new larger chunk.  In order for
+** this mem3.iMaster replacement to work, the master chunk must be
 ** linked into the hash tables.  That is not the normal state of
 ** affairs, of course.  The calling routine must link the master
 ** chunk before invoking this routine, then must unlink the (possibly
@@ -12063,31 +13455,31 @@ static void *memsys3FromMaster(int nBlock){
 static void memsys3Merge(u32 *pRoot){
   u32 iNext, prev, size, i, x;
 
-  assert( sqlite3_mutex_held(mem.mutex) );
+  assert( sqlite3_mutex_held(mem3.mutex) );
   for(i=*pRoot; i>0; i=iNext){
-    iNext = mem.aPool[i].u.list.next;
-    size = mem.aPool[i-1].u.hdr.size4x;
+    iNext = mem3.aPool[i].u.list.next;
+    size = mem3.aPool[i-1].u.hdr.size4x;
     assert( (size&1)==0 );
     if( (size&2)==0 ){
       memsys3UnlinkFromList(i, pRoot);
-      assert( i > mem.aPool[i-1].u.hdr.prevSize );
-      prev = i - mem.aPool[i-1].u.hdr.prevSize;
+      assert( i > mem3.aPool[i-1].u.hdr.prevSize );
+      prev = i - mem3.aPool[i-1].u.hdr.prevSize;
       if( prev==iNext ){
-        iNext = mem.aPool[prev].u.list.next;
+        iNext = mem3.aPool[prev].u.list.next;
       }
       memsys3Unlink(prev);
       size = i + size/4 - prev;
-      x = mem.aPool[prev-1].u.hdr.size4x & 2;
-      mem.aPool[prev-1].u.hdr.size4x = size*4 | x;
-      mem.aPool[prev+size-1].u.hdr.prevSize = size;
+      x = mem3.aPool[prev-1].u.hdr.size4x & 2;
+      mem3.aPool[prev-1].u.hdr.size4x = size*4 | x;
+      mem3.aPool[prev+size-1].u.hdr.prevSize = size;
       memsys3Link(prev);
       i = prev;
     }else{
       size /= 4;
     }
-    if( size>mem.szMaster ){
-      mem.iMaster = i;
-      mem.szMaster = size;
+    if( size>mem3.szMaster ){
+      mem3.iMaster = i;
+      mem3.szMaster = size;
     }
   }
 }
@@ -12095,20 +13487,23 @@ static void memsys3Merge(u32 *pRoot){
 /*
 ** Return a block of memory of at least nBytes in size.
 ** Return NULL if unable.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
 */
-static void *memsys3Malloc(int nByte){
+static void *memsys3MallocUnsafe(int nByte){
   u32 i;
-  int nBlock;
-  int toFree;
+  u32 nBlock;
+  u32 toFree;
 
-  assert( sqlite3_mutex_held(mem.mutex) );
+  assert( sqlite3_mutex_held(mem3.mutex) );
   assert( sizeof(Mem3Block)==8 );
   if( nByte<=12 ){
     nBlock = 2;
   }else{
     nBlock = (nByte + 11)/8;
   }
-  assert( nBlock >= 2 );
+  assert( nBlock>=2 );
 
   /* STEP 1:
   ** Look for an entry of the correct size in either the small
@@ -12116,16 +13511,16 @@ static void *memsys3Malloc(int nByte){
   ** successful most of the time (about 9 times out of 10).
   */
   if( nBlock <= MX_SMALL ){
-    i = mem.aiSmall[nBlock-2];
+    i = mem3.aiSmall[nBlock-2];
     if( i>0 ){
-      memsys3UnlinkFromList(i, &mem.aiSmall[nBlock-2]);
+      memsys3UnlinkFromList(i, &mem3.aiSmall[nBlock-2]);
       return memsys3Checkout(i, nBlock);
     }
   }else{
     int hash = nBlock % N_HASH;
-    for(i=mem.aiHash[hash]; i>0; i=mem.aPool[i].u.list.next){
-      if( mem.aPool[i-1].u.hdr.size4x/4==nBlock ){
-        memsys3UnlinkFromList(i, &mem.aiHash[hash]);
+    for(i=mem3.aiHash[hash]; i>0; i=mem3.aPool[i].u.list.next){
+      if( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ){
+        memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
         return memsys3Checkout(i, nBlock);
       }
     }
@@ -12135,7 +13530,7 @@ static void *memsys3Malloc(int nByte){
   ** Try to satisfy the allocation by carving a piece off of the end
   ** of the master chunk.  This step usually works if step 1 fails.
   */
-  if( mem.szMaster>=nBlock ){
+  if( mem3.szMaster>=nBlock ){
     return memsys3FromMaster(nBlock);
   }
 
@@ -12147,22 +13542,22 @@ static void *memsys3Malloc(int nByte){
   ** of the end of the master chunk.  This step happens very
   ** rarely (we hope!)
   */
-  for(toFree=nBlock*16; toFree<SQLITE_MEMORY_SIZE*2; toFree *= 2){
+  for(toFree=nBlock*16; toFree<(mem3.nPool*16); toFree *= 2){
     memsys3OutOfMemory(toFree);
-    if( mem.iMaster ){
-      memsys3Link(mem.iMaster);
-      mem.iMaster = 0;
-      mem.szMaster = 0;
+    if( mem3.iMaster ){
+      memsys3Link(mem3.iMaster);
+      mem3.iMaster = 0;
+      mem3.szMaster = 0;
     }
     for(i=0; i<N_HASH; i++){
-      memsys3Merge(&mem.aiHash[i]);
+      memsys3Merge(&mem3.aiHash[i]);
     }
     for(i=0; i<MX_SMALL-1; i++){
-      memsys3Merge(&mem.aiSmall[i]);
+      memsys3Merge(&mem3.aiSmall[i]);
     }
-    if( mem.szMaster ){
-      memsys3Unlink(mem.iMaster);
-      if( mem.szMaster>=nBlock ){
+    if( mem3.szMaster ){
+      memsys3Unlink(mem3.iMaster);
+      if( mem3.szMaster>=nBlock ){
         return memsys3FromMaster(nBlock);
       }
     }
@@ -12174,73 +13569,96 @@ static void *memsys3Malloc(int nByte){
 
 /*
 ** Free an outstanding memory allocation.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
 */
-void memsys3Free(void *pOld){
+void memsys3FreeUnsafe(void *pOld){
   Mem3Block *p = (Mem3Block*)pOld;
   int i;
   u32 size, x;
-  assert( sqlite3_mutex_held(mem.mutex) );
-  assert( p>mem.aPool && p<&mem.aPool[SQLITE_MEMORY_SIZE/8] );
-  i = p - mem.aPool;
-  assert( (mem.aPool[i-1].u.hdr.size4x&1)==1 );
-  size = mem.aPool[i-1].u.hdr.size4x/4;
-  assert( i+size<=SQLITE_MEMORY_SIZE/8+1 );
-  mem.aPool[i-1].u.hdr.size4x &= ~1;
-  mem.aPool[i+size-1].u.hdr.prevSize = size;
-  mem.aPool[i+size-1].u.hdr.size4x &= ~2;
+  assert( sqlite3_mutex_held(mem3.mutex) );
+  assert( p>mem3.aPool && p<&mem3.aPool[mem3.nPool] );
+  i = p - mem3.aPool;
+  assert( (mem3.aPool[i-1].u.hdr.size4x&1)==1 );
+  size = mem3.aPool[i-1].u.hdr.size4x/4;
+  assert( i+size<=mem3.nPool+1 );
+  mem3.aPool[i-1].u.hdr.size4x &= ~1;
+  mem3.aPool[i+size-1].u.hdr.prevSize = size;
+  mem3.aPool[i+size-1].u.hdr.size4x &= ~2;
   memsys3Link(i);
 
   /* Try to expand the master using the newly freed chunk */
-  if( mem.iMaster ){
-    while( (mem.aPool[mem.iMaster-1].u.hdr.size4x&2)==0 ){
-      size = mem.aPool[mem.iMaster-1].u.hdr.prevSize;
-      mem.iMaster -= size;
-      mem.szMaster += size;
-      memsys3Unlink(mem.iMaster);
-      x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
-      mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
-      mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = mem.szMaster;
+  if( mem3.iMaster ){
+    while( (mem3.aPool[mem3.iMaster-1].u.hdr.size4x&2)==0 ){
+      size = mem3.aPool[mem3.iMaster-1].u.hdr.prevSize;
+      mem3.iMaster -= size;
+      mem3.szMaster += size;
+      memsys3Unlink(mem3.iMaster);
+      x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+      mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+      mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
     }
-    x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
-    while( (mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x&1)==0 ){
-      memsys3Unlink(mem.iMaster+mem.szMaster);
-      mem.szMaster += mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x/4;
-      mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
-      mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = mem.szMaster;
+    x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+    while( (mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x&1)==0 ){
+      memsys3Unlink(mem3.iMaster+mem3.szMaster);
+      mem3.szMaster += mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x/4;
+      mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+      mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
     }
   }
 }
 
 /*
-** Allocate nBytes of memory
+** Return the size of an outstanding allocation, in bytes.  The
+** size returned omits the 8-byte header overhead.  This only
+** works for chunks that are currently checked out.
 */
-SQLITE_API void *sqlite3_malloc(int nBytes){
-  sqlite3_int64 *p = 0;
-  if( nBytes>0 ){
-    memsys3Enter();
-    p = memsys3Malloc(nBytes);
-    sqlite3_mutex_leave(mem.mutex);
+static int memsys3Size(void *p){
+  Mem3Block *pBlock;
+  if( p==0 ) return 0;
+  pBlock = (Mem3Block*)p;
+  assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
+  return (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int memsys3Roundup(int n){
+  if( n<=12 ){
+    return 12;
+  }else{
+    return ((n+11)&~7) - 4;
   }
+}
+
+/*
+** Allocate nBytes of memory.
+*/
+static void *memsys3Malloc(int nBytes){
+  sqlite3_int64 *p;
+  assert( nBytes>0 );          /* malloc.c filters out 0 byte requests */
+  memsys3Enter();
+  p = memsys3MallocUnsafe(nBytes);
+  memsys3Leave();
   return (void*)p; 
 }
 
 /*
 ** Free memory.
 */
-SQLITE_API void sqlite3_free(void *pPrior){
-  if( pPrior==0 ){
-    return;
-  }
-  assert( mem.mutex!=0 );
-  sqlite3_mutex_enter(mem.mutex);
-  memsys3Free(pPrior);
-  sqlite3_mutex_leave(mem.mutex);  
+void memsys3Free(void *pPrior){
+  assert( pPrior );
+  memsys3Enter();
+  memsys3FreeUnsafe(pPrior);
+  memsys3Leave();
 }
 
 /*
 ** Change the size of an existing memory allocation
 */
-SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
+void *memsys3Realloc(void *pPrior, int nBytes){
   int nOld;
   void *p;
   if( pPrior==0 ){
@@ -12250,33 +13668,68 @@ SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
     sqlite3_free(pPrior);
     return 0;
   }
-  assert( mem.mutex!=0 );
-  nOld = sqlite3MallocSize(pPrior);
+  nOld = memsys3Size(pPrior);
   if( nBytes<=nOld && nBytes>=nOld-128 ){
     return pPrior;
   }
-  sqlite3_mutex_enter(mem.mutex);
-  p = memsys3Malloc(nBytes);
+  memsys3Enter();
+  p = memsys3MallocUnsafe(nBytes);
   if( p ){
     if( nOld<nBytes ){
       memcpy(p, pPrior, nOld);
     }else{
       memcpy(p, pPrior, nBytes);
     }
-    memsys3Free(pPrior);
+    memsys3FreeUnsafe(pPrior);
   }
-  sqlite3_mutex_leave(mem.mutex);
+  memsys3Leave();
   return p;
 }
 
 /*
+** Initialize this module.
+*/
+static int memsys3Init(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  if( !sqlite3GlobalConfig.pHeap ){
+    return SQLITE_ERROR;
+  }
+
+  /* Store a pointer to the memory block in global structure mem3. */
+  assert( sizeof(Mem3Block)==8 );
+  mem3.aPool = (Mem3Block *)sqlite3GlobalConfig.pHeap;
+  mem3.nPool = (sqlite3GlobalConfig.nHeap / sizeof(Mem3Block)) - 2;
+
+  /* Initialize the master block. */
+  mem3.szMaster = mem3.nPool;
+  mem3.mnMaster = mem3.szMaster;
+  mem3.iMaster = 1;
+  mem3.aPool[0].u.hdr.size4x = (mem3.szMaster<<2) + 2;
+  mem3.aPool[mem3.nPool].u.hdr.prevSize = mem3.nPool;
+  mem3.aPool[mem3.nPool].u.hdr.size4x = 1;
+
+  return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void memsys3Shutdown(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  mem3.mutex = 0;
+  return;
+}
+
+
+
+/*
 ** Open the file indicated and write a log of all unfreed memory 
 ** allocations into that log.
 */
-SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
+SQLITE_PRIVATE void sqlite3Memsys3Dump(const char *zFilename){
 #ifdef SQLITE_DEBUG
   FILE *out;
-  int i, j;
+  u32 i, j;
   u32 size;
   if( zFilename==0 || zFilename[0]==0 ){
     out = stdout;
@@ -12290,62 +13743,88 @@ SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
   }
   memsys3Enter();
   fprintf(out, "CHUNKS:\n");
-  for(i=1; i<=SQLITE_MEMORY_SIZE/8; i+=size/4){
-    size = mem.aPool[i-1].u.hdr.size4x;
+  for(i=1; i<=mem3.nPool; i+=size/4){
+    size = mem3.aPool[i-1].u.hdr.size4x;
     if( size/4<=1 ){
-      fprintf(out, "%p size error\n", &mem.aPool[i]);
+      fprintf(out, "%p size error\n", &mem3.aPool[i]);
       assert( 0 );
       break;
     }
-    if( (size&1)==0 && mem.aPool[i+size/4-1].u.hdr.prevSize!=size/4 ){
-      fprintf(out, "%p tail size does not match\n", &mem.aPool[i]);
+    if( (size&1)==0 && mem3.aPool[i+size/4-1].u.hdr.prevSize!=size/4 ){
+      fprintf(out, "%p tail size does not match\n", &mem3.aPool[i]);
       assert( 0 );
       break;
     }
-    if( ((mem.aPool[i+size/4-1].u.hdr.size4x&2)>>1)!=(size&1) ){
-      fprintf(out, "%p tail checkout bit is incorrect\n", &mem.aPool[i]);
+    if( ((mem3.aPool[i+size/4-1].u.hdr.size4x&2)>>1)!=(size&1) ){
+      fprintf(out, "%p tail checkout bit is incorrect\n", &mem3.aPool[i]);
       assert( 0 );
       break;
     }
     if( size&1 ){
-      fprintf(out, "%p %6d bytes checked out\n", &mem.aPool[i], (size/4)*8-8);
+      fprintf(out, "%p %6d bytes checked out\n", &mem3.aPool[i], (size/4)*8-8);
     }else{
-      fprintf(out, "%p %6d bytes free%s\n", &mem.aPool[i], (size/4)*8-8,
-                  i==mem.iMaster ? " **master**" : "");
+      fprintf(out, "%p %6d bytes free%s\n", &mem3.aPool[i], (size/4)*8-8,
+                  i==mem3.iMaster ? " **master**" : "");
     }
   }
   for(i=0; i<MX_SMALL-1; i++){
-    if( mem.aiSmall[i]==0 ) continue;
+    if( mem3.aiSmall[i]==0 ) continue;
     fprintf(out, "small(%2d):", i);
-    for(j = mem.aiSmall[i]; j>0; j=mem.aPool[j].u.list.next){
-      fprintf(out, " %p(%d)", &mem.aPool[j],
-              (mem.aPool[j-1].u.hdr.size4x/4)*8-8);
+    for(j = mem3.aiSmall[i]; j>0; j=mem3.aPool[j].u.list.next){
+      fprintf(out, " %p(%d)", &mem3.aPool[j],
+              (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
     }
     fprintf(out, "\n"); 
   }
   for(i=0; i<N_HASH; i++){
-    if( mem.aiHash[i]==0 ) continue;
+    if( mem3.aiHash[i]==0 ) continue;
     fprintf(out, "hash(%2d):", i);
-    for(j = mem.aiHash[i]; j>0; j=mem.aPool[j].u.list.next){
-      fprintf(out, " %p(%d)", &mem.aPool[j],
-              (mem.aPool[j-1].u.hdr.size4x/4)*8-8);
+    for(j = mem3.aiHash[i]; j>0; j=mem3.aPool[j].u.list.next){
+      fprintf(out, " %p(%d)", &mem3.aPool[j],
+              (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
     }
     fprintf(out, "\n"); 
   }
-  fprintf(out, "master=%d\n", mem.iMaster);
-  fprintf(out, "nowUsed=%d\n", SQLITE_MEMORY_SIZE - mem.szMaster*8);
-  fprintf(out, "mxUsed=%d\n", SQLITE_MEMORY_SIZE - mem.mnMaster*8);
-  sqlite3_mutex_leave(mem.mutex);
+  fprintf(out, "master=%d\n", mem3.iMaster);
+  fprintf(out, "nowUsed=%d\n", mem3.nPool*8 - mem3.szMaster*8);
+  fprintf(out, "mxUsed=%d\n", mem3.nPool*8 - mem3.mnMaster*8);
+  sqlite3_mutex_leave(mem3.mutex);
   if( out==stdout ){
     fflush(stdout);
   }else{
     fclose(out);
   }
+#else
+  UNUSED_PARAMETER(zFilename);
 #endif
 }
 
+/*
+** This routine is the only routine in this file with external 
+** linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file. The
+** arguments specify the block of memory to manage.
+**
+** This routine is only called by sqlite3_config(), and therefore
+** is not required to be threadsafe (it is not).
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void){
+  static const sqlite3_mem_methods mempoolMethods = {
+     memsys3Malloc,
+     memsys3Free,
+     memsys3Realloc,
+     memsys3Size,
+     memsys3Roundup,
+     memsys3Init,
+     memsys3Shutdown,
+     0
+  };
+  return &mempoolMethods;
+}
 
-#endif /* !SQLITE_MEMORY_SIZE */
+#endif /* SQLITE_ENABLE_MEMSYS3 */
 
 /************** End of mem3.c ************************************************/
 /************** Begin file mem5.c ********************************************/
@@ -12364,95 +13843,88 @@ SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
 ** allocation subsystem for use by SQLite. 
 **
 ** This version of the memory allocation subsystem omits all
-** use of malloc().  All dynamically allocatable memory is
-** contained in a static array, mem.aPool[].  The size of this
-** fixed memory pool is SQLITE_POW2_MEMORY_SIZE bytes.
+** use of malloc(). The application gives SQLite a block of memory
+** before calling sqlite3_initialize() from which allocations
+** are made and returned by the xMalloc() and xRealloc() 
+** implementations. Once sqlite3_initialize() has been called,
+** the amount of memory available to SQLite is fixed and cannot
+** be changed.
+**
+** This version of the memory allocation subsystem is included
+** in the build only if SQLITE_ENABLE_MEMSYS5 is defined.
+**
+** This memory allocator uses the following algorithm:
+**
+**   1.  All memory allocations sizes are rounded up to a power of 2.
+**
+**   2.  If two adjacent free blocks are the halves of a larger block,
+**       then the two blocks are coalesed into the single larger block.
+**
+**   3.  New memory is allocated from the first available free block.
 **
-** This version of the memory allocation subsystem is used if
-** and only if SQLITE_POW2_MEMORY_SIZE is defined.
+** This algorithm is described in: J. M. Robson. "Bounds for Some Functions
+** Concerning Dynamic Storage Allocation". Journal of the Association for
+** Computing Machinery, Volume 21, Number 8, July 1974, pages 491-499.
+** 
+** Let n be the size of the largest allocation divided by the minimum
+** allocation size (after rounding all sizes up to a power of 2.)  Let M
+** be the maximum amount of memory ever outstanding at one time.  Let
+** N be the total amount of memory available for allocation.  Robson
+** proved that this memory allocator will never breakdown due to 
+** fragmentation as long as the following constraint holds:
+**
+**      N >=  M*(1 + log2(n)/2) - n + 1
 **
-** $Id: mem5.c,v 1.4 2008/02/19 15:15:16 drh Exp $
+** The sqlite3_status() logic tracks the maximum values of n and M so
+** that an application can, at any time, verify this constraint.
 */
 
 /*
 ** This version of the memory allocator is used only when 
-** SQLITE_POW2_MEMORY_SIZE is defined.
-*/
-#ifdef SQLITE_POW2_MEMORY_SIZE
-
-/*
-** Log2 of the minimum size of an allocation.  For example, if
-** 4 then all allocations will be rounded up to at least 16 bytes.
-** If 5 then all allocations will be rounded up to at least 32 bytes.
+** SQLITE_ENABLE_MEMSYS5 is defined.
 */
-#ifndef SQLITE_POW2_LOGMIN
-# define SQLITE_POW2_LOGMIN 6
-#endif
-#define POW2_MIN (1<<SQLITE_POW2_LOGMIN)
-
-/*
-** Log2 of the maximum size of an allocation.
-*/
-#ifndef SQLITE_POW2_LOGMAX
-# define SQLITE_POW2_LOGMAX 18
-#endif
-#define POW2_MAX (((unsigned int)1)<<SQLITE_POW2_LOGMAX)
-
-/*
-** Number of distinct allocation sizes.
-*/
-#define NSIZE (SQLITE_POW2_LOGMAX - SQLITE_POW2_LOGMIN + 1)
+#ifdef SQLITE_ENABLE_MEMSYS5
 
 /*
 ** A minimum allocation is an instance of the following structure.
 ** Larger allocations are an array of these structures where the
 ** size of the array is a power of 2.
+**
+** The size of this object must be a power of two.  That fact is
+** verified in memsys5Init().
 */
-typedef struct Mem5Block Mem5Block;
-struct Mem5Block {
-  union {
-    char aData[POW2_MIN];
-    struct {
-      int next;       /* Index in mem.aPool[] of next free chunk */
-      int prev;       /* Index in mem.aPool[] of previous free chunk */
-    } list;
-  } u;
+typedef struct Mem5Link Mem5Link;
+struct Mem5Link {
+  int next;       /* Index of next free chunk */
+  int prev;       /* Index of previous free chunk */
 };
 
 /*
-** Number of blocks of memory available for allocation.
-*/
-#define NBLOCK (SQLITE_POW2_MEMORY_SIZE/POW2_MIN)
-
-/*
-** The size in blocks of an POW2_MAX allocation
+** Maximum size of any allocation is ((1<<LOGMAX)*mem5.szAtom). Since
+** mem5.szAtom is always at least 8 and 32-bit integers are used,
+** it is not actually possible to reach this limit.
 */
-#define SZ_MAX (1<<(NSIZE-1))
+#define LOGMAX 30
 
 /*
-** Masks used for mem.aCtrl[] elements.
+** Masks used for mem5.aCtrl[] elements.
 */
-#define CTRL_LOGSIZE  0x1f    /* Log2 Size of this block relative to POW2_MIN */
+#define CTRL_LOGSIZE  0x1f    /* Log2 Size of this block */
 #define CTRL_FREE     0x20    /* True if not checked out */
 
 /*
 ** All of the static variables used by this module are collected
-** into a single structure named "mem".  This is to keep the
+** into a single structure named "mem5".  This is to keep the
 ** static variables organized and to reduce namespace pollution
 ** when this module is combined with other in the amalgamation.
 */
-static struct {
+static SQLITE_WSD struct Mem5Global {
   /*
-  ** The alarm callback and its arguments.  The mem.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.  The alarmBusy variable is set to prevent recursive
-  ** callbacks.
+  ** Memory available for allocation
   */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64,int);
-  void *alarmArg;
-  int alarmBusy;
+  int szAtom;      /* Smallest possible allocation in bytes */
+  int nBlock;      /* Number of szAtom sized blocks in zPool */
+  u8 *zPool;       /* Memory available to be allocated */
   
   /*
   ** Mutex to control access to the memory allocation subsystem.
@@ -12472,150 +13944,83 @@ static struct {
   u32 maxRequest;     /* Largest allocation (exclusive of internal frag) */
   
   /*
-  ** Lists of free blocks of various sizes.
+  ** Lists of free blocks.  aiFreelist[0] is a list of free blocks of
+  ** size mem5.szAtom.  aiFreelist[1] holds blocks of size szAtom*2.
+  ** and so forth.
   */
-  int aiFreelist[NSIZE];
+  int aiFreelist[LOGMAX+1];
 
   /*
   ** Space for tracking which blocks are checked out and the size
   ** of each block.  One byte per block.
   */
-  u8 aCtrl[NBLOCK];
+  u8 *aCtrl;
 
-  /*
-  ** Memory available for allocation
-  */
-  Mem5Block aPool[NBLOCK];
-} mem;
+} mem5 = { 0 };
+
+/*
+** Access the static variable through a macro for SQLITE_OMIT_WSD
+*/
+#define mem5 GLOBAL(struct Mem5Global, mem5)
+
+/*
+** Assuming mem5.zPool is divided up into an array of Mem5Link
+** structures, return a pointer to the idx-th such lik.
+*/
+#define MEM5LINK(idx) ((Mem5Link *)(&mem5.zPool[(idx)*mem5.szAtom]))
 
 /*
-** Unlink the chunk at mem.aPool[i] from list it is currently
-** on.  It should be found on mem.aiFreelist[iLogsize].
+** Unlink the chunk at mem5.aPool[i] from list it is currently
+** on.  It should be found on mem5.aiFreelist[iLogsize].
 */
 static void memsys5Unlink(int i, int iLogsize){
   int next, prev;
-  assert( i>=0 && i<NBLOCK );
-  assert( iLogsize>=0 && iLogsize<NSIZE );
-  assert( (mem.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
-  assert( sqlite3_mutex_held(mem.mutex) );
+  assert( i>=0 && i<mem5.nBlock );
+  assert( iLogsize>=0 && iLogsize<=LOGMAX );
+  assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
 
-  next = mem.aPool[i].u.list.next;
-  prev = mem.aPool[i].u.list.prev;
+  next = MEM5LINK(i)->next;
+  prev = MEM5LINK(i)->prev;
   if( prev<0 ){
-    mem.aiFreelist[iLogsize] = next;
+    mem5.aiFreelist[iLogsize] = next;
   }else{
-    mem.aPool[prev].u.list.next = next;
+    MEM5LINK(prev)->next = next;
   }
   if( next>=0 ){
-    mem.aPool[next].u.list.prev = prev;
+    MEM5LINK(next)->prev = prev;
   }
 }
 
 /*
-** Link the chunk at mem.aPool[i] so that is on the iLogsize
+** Link the chunk at mem5.aPool[i] so that is on the iLogsize
 ** free list.
 */
 static void memsys5Link(int i, int iLogsize){
   int x;
-  assert( sqlite3_mutex_held(mem.mutex) );
-  assert( i>=0 && i<NBLOCK );
-  assert( iLogsize>=0 && iLogsize<NSIZE );
-  assert( (mem.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
+  assert( sqlite3_mutex_held(mem5.mutex) );
+  assert( i>=0 && i<mem5.nBlock );
+  assert( iLogsize>=0 && iLogsize<=LOGMAX );
+  assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
 
-  mem.aPool[i].u.list.next = x = mem.aiFreelist[iLogsize];
-  mem.aPool[i].u.list.prev = -1;
+  x = MEM5LINK(i)->next = mem5.aiFreelist[iLogsize];
+  MEM5LINK(i)->prev = -1;
   if( x>=0 ){
-    assert( x<NBLOCK );
-    mem.aPool[x].u.list.prev = i;
+    assert( x<mem5.nBlock );
+    MEM5LINK(x)->prev = i;
   }
-  mem.aiFreelist[iLogsize] = i;
+  mem5.aiFreelist[iLogsize] = i;
 }
 
 /*
-** Enter the mutex mem.mutex. Allocate it if it is not already allocated.
-**
-** Also:  Initialize the memory allocation subsystem the first time
-** this routine is called.
+** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
+** will already be held (obtained by code in malloc.c) if
+** sqlite3GlobalConfig.bMemStat is true.
 */
 static void memsys5Enter(void){
-  if( mem.mutex==0 ){
-    int i;
-    assert( sizeof(Mem5Block)==POW2_MIN );
-    assert( (SQLITE_POW2_MEMORY_SIZE % POW2_MAX)==0 );
-    assert( SQLITE_POW2_MEMORY_SIZE>=POW2_MAX );
-    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
-    sqlite3_mutex_enter(mem.mutex);
-    for(i=0; i<NSIZE; i++) mem.aiFreelist[i] = -1;
-    for(i=0; i<=NBLOCK-SZ_MAX; i += SZ_MAX){
-      mem.aCtrl[i] = (NSIZE-1) | CTRL_FREE;
-      memsys5Link(i, NSIZE-1);
-    }
-  }else{
-    sqlite3_mutex_enter(mem.mutex);
-  }
-}
-
-/*
-** Return the amount of memory currently checked out.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
-  return mem.currentOut;
-}
-
-/*
-** Return the maximum amount of memory that has ever been
-** checked out since either the beginning of this process
-** or since the most recent reset.
-*/
-SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
-  sqlite3_int64 n;
-  memsys5Enter();
-  n = mem.maxOut;
-  if( resetFlag ){
-    mem.maxOut = mem.currentOut;
-  }
-  sqlite3_mutex_leave(mem.mutex);  
-  return n;
+  sqlite3_mutex_enter(mem5.mutex);
 }
-
-
-/*
-** Trigger the alarm 
-*/
-static void memsys5Alarm(int nByte){
-  void (*xCallback)(void*,sqlite3_int64,int);
-  sqlite3_int64 nowUsed;
-  void *pArg;
-  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
-  mem.alarmBusy = 1;
-  xCallback = mem.alarmCallback;
-  nowUsed = mem.currentOut;
-  pArg = mem.alarmArg;
-  sqlite3_mutex_leave(mem.mutex);
-  xCallback(pArg, nowUsed, nByte);
-  sqlite3_mutex_enter(mem.mutex);
-  mem.alarmBusy = 0;
-}
-
-/*
-** Change the alarm callback.
-**
-** This is a no-op for the static memory allocator.  The purpose
-** of the memory alarm is to support sqlite3_soft_heap_limit().
-** But with this memory allocator, the soft_heap_limit is really
-** a hard limit that is fixed at SQLITE_POW2_MEMORY_SIZE.
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  memsys5Enter();
-  mem.alarmCallback = xCallback;
-  mem.alarmArg = pArg;
-  mem.alarmThreshold = iThreshold;
-  sqlite3_mutex_leave(mem.mutex);
-  return SQLITE_OK;
+static void memsys5Leave(void){
+  sqlite3_mutex_leave(mem5.mutex);
 }
 
 /*
@@ -12623,12 +14028,12 @@ SQLITE_API int sqlite3_memory_alarm(
 ** size returned omits the 8-byte header overhead.  This only
 ** works for chunks that are currently checked out.
 */
-SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+static int memsys5Size(void *p){
   int iSize = 0;
   if( p ){
-    int i = ((Mem5Block*)p) - mem.aPool;
-    assert( i>=0 && i<NBLOCK );
-    iSize = 1 << ((mem.aCtrl[i]&CTRL_LOGSIZE) + SQLITE_POW2_LOGMIN);
+    int i = ((u8 *)p-mem5.zPool)/mem5.szAtom;
+    assert( i>=0 && i<mem5.nBlock );
+    iSize = mem5.szAtom * (1 << (mem5.aCtrl[i]&CTRL_LOGSIZE));
   }
   return iSize;
 }
@@ -12641,12 +14046,12 @@ static int memsys5UnlinkFirst(int iLogsize){
   int i;
   int iFirst;
 
-  assert( iLogsize>=0 && iLogsize<NSIZE );
-  i = iFirst = mem.aiFreelist[iLogsize];
+  assert( iLogsize>=0 && iLogsize<=LOGMAX );
+  i = iFirst = mem5.aiFreelist[iLogsize];
   assert( iFirst>=0 );
   while( i>0 ){
     if( i<iFirst ) iFirst = i;
-    i = mem.aPool[i].u.list.next;
+    i = MEM5LINK(i)->next;
   }
   memsys5Unlink(iFirst, iLogsize);
   return iFirst;
@@ -12654,176 +14059,296 @@ static int memsys5UnlinkFirst(int iLogsize){
 
 /*
 ** Return a block of memory of at least nBytes in size.
-** Return NULL if unable.
+** Return NULL if unable.  Return NULL if nBytes==0.
+**
+** The caller guarantees that nByte positive.
+**
+** The caller has obtained a mutex prior to invoking this
+** routine so there is never any chance that two or more
+** threads can be in this routine at the same time.
 */
-static void *memsys5Malloc(int nByte){
-  int i;           /* Index of a mem.aPool[] slot */
-  int iBin;        /* Index into mem.aiFreelist[] */
+static void *memsys5MallocUnsafe(int nByte){
+  int i;           /* Index of a mem5.aPool[] slot */
+  int iBin;        /* Index into mem5.aiFreelist[] */
   int iFullSz;     /* Size of allocation rounded up to power of 2 */
   int iLogsize;    /* Log2 of iFullSz/POW2_MIN */
 
-  assert( sqlite3_mutex_held(mem.mutex) );
+  /* nByte must be a positive */
+  assert( nByte>0 );
 
   /* Keep track of the maximum allocation request.  Even unfulfilled
   ** requests are counted */
-  if( nByte>mem.maxRequest ){
-    mem.maxRequest = nByte;
+  if( (u32)nByte>mem5.maxRequest ){
+    mem5.maxRequest = nByte;
   }
 
-  /* Simulate a memory allocation fault */
-  if( sqlite3FaultStep(SQLITE_FAULTINJECTOR_MALLOC) ) return 0;
+  /* Abort if the requested allocation size is larger than the largest
+  ** power of two that we can represent using 32-bit signed integers.
+  */
+  if( nByte > 0x40000000 ){
+    return 0;
+  }
 
   /* Round nByte up to the next valid power of two */
-  if( nByte>POW2_MAX ) return 0;
-  for(iFullSz=POW2_MIN, iLogsize=0; iFullSz<nByte; iFullSz *= 2, iLogsize++){}
-
-  /* If we will be over the memory alarm threshold after this allocation,
-  ** then trigger the memory overflow alarm */
-  if( mem.alarmCallback!=0 && mem.currentOut+iFullSz>=mem.alarmThreshold ){
-    memsys5Alarm(iFullSz);
-  }
+  for(iFullSz=mem5.szAtom, iLogsize=0; iFullSz<nByte; iFullSz *= 2, iLogsize++){}
 
-  /* Make sure mem.aiFreelist[iLogsize] contains at least one free
+  /* Make sure mem5.aiFreelist[iLogsize] contains at least one free
   ** block.  If not, then split a block of the next larger power of
   ** two in order to create a new free block of size iLogsize.
   */
-  for(iBin=iLogsize; mem.aiFreelist[iBin]<0 && iBin<NSIZE; iBin++){}
-  if( iBin>=NSIZE ) return 0;
+  for(iBin=iLogsize; mem5.aiFreelist[iBin]<0 && iBin<=LOGMAX; iBin++){}
+  if( iBin>LOGMAX ) return 0;
   i = memsys5UnlinkFirst(iBin);
   while( iBin>iLogsize ){
     int newSize;
 
     iBin--;
     newSize = 1 << iBin;
-    mem.aCtrl[i+newSize] = CTRL_FREE | iBin;
+    mem5.aCtrl[i+newSize] = CTRL_FREE | iBin;
     memsys5Link(i+newSize, iBin);
   }
-  mem.aCtrl[i] = iLogsize;
+  mem5.aCtrl[i] = iLogsize;
 
   /* Update allocator performance statistics. */
-  mem.nAlloc++;
-  mem.totalAlloc += iFullSz;
-  mem.totalExcess += iFullSz - nByte;
-  mem.currentCount++;
-  mem.currentOut += iFullSz;
-  if( mem.maxCount<mem.currentCount ) mem.maxCount = mem.currentCount;
-  if( mem.maxOut<mem.currentOut ) mem.maxOut = mem.currentOut;
+  mem5.nAlloc++;
+  mem5.totalAlloc += iFullSz;
+  mem5.totalExcess += iFullSz - nByte;
+  mem5.currentCount++;
+  mem5.currentOut += iFullSz;
+  if( mem5.maxCount<mem5.currentCount ) mem5.maxCount = mem5.currentCount;
+  if( mem5.maxOut<mem5.currentOut ) mem5.maxOut = mem5.currentOut;
 
   /* Return a pointer to the allocated memory. */
-  return (void*)&mem.aPool[i];
+  return (void*)&mem5.zPool[i*mem5.szAtom];
 }
 
 /*
 ** Free an outstanding memory allocation.
 */
-void memsys5Free(void *pOld){
+static void memsys5FreeUnsafe(void *pOld){
   u32 size, iLogsize;
-  int i;
+  int iBlock;
+
+  /* Set iBlock to the index of the block pointed to by pOld in 
+  ** the array of mem5.szAtom byte blocks pointed to by mem5.zPool.
+  */
+  iBlock = ((u8 *)pOld-mem5.zPool)/mem5.szAtom;
 
-  i = ((Mem5Block*)pOld) - mem.aPool;
-  assert( sqlite3_mutex_held(mem.mutex) );
-  assert( i>=0 && i<NBLOCK );
-  assert( (mem.aCtrl[i] & CTRL_FREE)==0 );
-  iLogsize = mem.aCtrl[i] & CTRL_LOGSIZE;
+  /* Check that the pointer pOld points to a valid, non-free block. */
+  assert( iBlock>=0 && iBlock<mem5.nBlock );
+  assert( ((u8 *)pOld-mem5.zPool)%mem5.szAtom==0 );
+  assert( (mem5.aCtrl[iBlock] & CTRL_FREE)==0 );
+
+  iLogsize = mem5.aCtrl[iBlock] & CTRL_LOGSIZE;
   size = 1<<iLogsize;
-  assert( i+size-1<NBLOCK );
-  mem.aCtrl[i] |= CTRL_FREE;
-  mem.aCtrl[i+size-1] |= CTRL_FREE;
-  assert( mem.currentCount>0 );
-  assert( mem.currentOut>=0 );
-  mem.currentCount--;
-  mem.currentOut -= size*POW2_MIN;
-  assert( mem.currentOut>0 || mem.currentCount==0 );
-  assert( mem.currentCount>0 || mem.currentOut==0 );
-
-  mem.aCtrl[i] = CTRL_FREE | iLogsize;
-  while( iLogsize<NSIZE-1 ){
+  assert( iBlock+size-1<(u32)mem5.nBlock );
+
+  mem5.aCtrl[iBlock] |= CTRL_FREE;
+  mem5.aCtrl[iBlock+size-1] |= CTRL_FREE;
+  assert( mem5.currentCount>0 );
+  assert( mem5.currentOut>=(size*mem5.szAtom) );
+  mem5.currentCount--;
+  mem5.currentOut -= size*mem5.szAtom;
+  assert( mem5.currentOut>0 || mem5.currentCount==0 );
+  assert( mem5.currentCount>0 || mem5.currentOut==0 );
+
+  mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
+  while( ALWAYS(iLogsize<LOGMAX) ){
     int iBuddy;
-
-    if( (i>>iLogsize) & 1 ){
-      iBuddy = i - size;
+    if( (iBlock>>iLogsize) & 1 ){
+      iBuddy = iBlock - size;
     }else{
-      iBuddy = i + size;
+      iBuddy = iBlock + size;
     }
-    assert( iBuddy>=0 && iBuddy<NBLOCK );
-    if( mem.aCtrl[iBuddy]!=(CTRL_FREE | iLogsize) ) break;
+    assert( iBuddy>=0 );
+    if( (iBuddy+(1<<iLogsize))>mem5.nBlock ) break;
+    if( mem5.aCtrl[iBuddy]!=(CTRL_FREE | iLogsize) ) break;
     memsys5Unlink(iBuddy, iLogsize);
     iLogsize++;
-    if( iBuddy<i ){
-      mem.aCtrl[iBuddy] = CTRL_FREE | iLogsize;
-      mem.aCtrl[i] = 0;
-      i = iBuddy;
+    if( iBuddy<iBlock ){
+      mem5.aCtrl[iBuddy] = CTRL_FREE | iLogsize;
+      mem5.aCtrl[iBlock] = 0;
+      iBlock = iBuddy;
     }else{
-      mem.aCtrl[i] = CTRL_FREE | iLogsize;
-      mem.aCtrl[iBuddy] = 0;
+      mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
+      mem5.aCtrl[iBuddy] = 0;
     }
     size *= 2;
   }
-  memsys5Link(i, iLogsize);
+  memsys5Link(iBlock, iLogsize);
 }
 
 /*
 ** Allocate nBytes of memory
 */
-SQLITE_API void *sqlite3_malloc(int nBytes){
+static void *memsys5Malloc(int nBytes){
   sqlite3_int64 *p = 0;
   if( nBytes>0 ){
     memsys5Enter();
-    p = memsys5Malloc(nBytes);
-    sqlite3_mutex_leave(mem.mutex);
+    p = memsys5MallocUnsafe(nBytes);
+    memsys5Leave();
   }
   return (void*)p; 
 }
 
 /*
 ** Free memory.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.
 */
-SQLITE_API void sqlite3_free(void *pPrior){
-  if( pPrior==0 ){
-    return;
-  }
-  assert( mem.mutex!=0 );
-  sqlite3_mutex_enter(mem.mutex);
-  memsys5Free(pPrior);
-  sqlite3_mutex_leave(mem.mutex);  
+static void memsys5Free(void *pPrior){
+  assert( pPrior!=0 );
+  memsys5Enter();
+  memsys5FreeUnsafe(pPrior);
+  memsys5Leave();  
 }
 
 /*
-** Change the size of an existing memory allocation
+** Change the size of an existing memory allocation.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.  
+**
+** nBytes is always a value obtained from a prior call to
+** memsys5Round().  Hence nBytes is always a non-negative power
+** of two.  If nBytes==0 that means that an oversize allocation
+** (an allocation larger than 0x40000000) was requested and this
+** routine should return 0 without freeing pPrior.
 */
-SQLITE_API void *sqlite3_realloc(void *pPrior, int nBytes){
+static void *memsys5Realloc(void *pPrior, int nBytes){
   int nOld;
   void *p;
-  if( pPrior==0 ){
-    return sqlite3_malloc(nBytes);
-  }
-  if( nBytes<=0 ){
-    sqlite3_free(pPrior);
+  assert( pPrior!=0 );
+  assert( (nBytes&(nBytes-1))==0 );
+  assert( nBytes>=0 );
+  if( nBytes==0 ){
     return 0;
   }
-  assert( mem.mutex!=0 );
-  nOld = sqlite3MallocSize(pPrior);
+  nOld = memsys5Size(pPrior);
   if( nBytes<=nOld ){
     return pPrior;
   }
-  sqlite3_mutex_enter(mem.mutex);
-  p = memsys5Malloc(nBytes);
+  memsys5Enter();
+  p = memsys5MallocUnsafe(nBytes);
   if( p ){
     memcpy(p, pPrior, nOld);
-    memsys5Free(pPrior);
+    memsys5FreeUnsafe(pPrior);
   }
-  sqlite3_mutex_leave(mem.mutex);
+  memsys5Leave();
   return p;
 }
 
 /*
+** Round up a request size to the next valid allocation size.  If
+** the allocation is too large to be handled by this allocation system,
+** return 0.
+**
+** All allocations must be a power of two and must be expressed by a
+** 32-bit signed integer.  Hence the largest allocation is 0x40000000
+** or 1073741824 bytes.
+*/
+static int memsys5Roundup(int n){
+  int iFullSz;
+  if( n > 0x40000000 ) return 0;
+  for(iFullSz=mem5.szAtom; iFullSz<n; iFullSz *= 2);
+  return iFullSz;
+}
+
+/*
+** Return the ceiling of the logarithm base 2 of iValue.
+**
+** Examples:   memsys5Log(1) -> 0
+**             memsys5Log(2) -> 1
+**             memsys5Log(4) -> 2
+**             memsys5Log(5) -> 3
+**             memsys5Log(8) -> 3
+**             memsys5Log(9) -> 4
+*/
+static int memsys5Log(int iValue){
+  int iLog;
+  for(iLog=0; (1<<iLog)<iValue; iLog++);
+  return iLog;
+}
+
+/*
+** Initialize the memory allocator.
+**
+** This routine is not threadsafe.  The caller must be holding a mutex
+** to prevent multiple threads from entering at the same time.
+*/
+static int memsys5Init(void *NotUsed){
+  int ii;            /* Loop counter */
+  int nByte;         /* Number of bytes of memory available to this allocator */
+  u8 *zByte;         /* Memory usable by this allocator */
+  int nMinLog;       /* Log base 2 of minimum allocation size in bytes */
+  int iOffset;       /* An offset into mem5.aCtrl[] */
+
+  UNUSED_PARAMETER(NotUsed);
+
+  /* For the purposes of this routine, disable the mutex */
+  mem5.mutex = 0;
+
+  /* The size of a Mem5Link object must be a power of two.  Verify that
+  ** this is case.
+  */
+  assert( (sizeof(Mem5Link)&(sizeof(Mem5Link)-1))==0 );
+
+  nByte = sqlite3GlobalConfig.nHeap;
+  zByte = (u8*)sqlite3GlobalConfig.pHeap;
+  assert( zByte!=0 );  /* sqlite3_config() does not allow otherwise */
+
+  nMinLog = memsys5Log(sqlite3GlobalConfig.mnReq);
+  mem5.szAtom = (1<<nMinLog);
+  while( (int)sizeof(Mem5Link)>mem5.szAtom ){
+    mem5.szAtom = mem5.szAtom << 1;
+  }
+
+  mem5.nBlock = (nByte / (mem5.szAtom+sizeof(u8)));
+  mem5.zPool = zByte;
+  mem5.aCtrl = (u8 *)&mem5.zPool[mem5.nBlock*mem5.szAtom];
+
+  for(ii=0; ii<=LOGMAX; ii++){
+    mem5.aiFreelist[ii] = -1;
+  }
+
+  iOffset = 0;
+  for(ii=LOGMAX; ii>=0; ii--){
+    int nAlloc = (1<<ii);
+    if( (iOffset+nAlloc)<=mem5.nBlock ){
+      mem5.aCtrl[iOffset] = ii | CTRL_FREE;
+      memsys5Link(iOffset, ii);
+      iOffset += nAlloc;
+    }
+    assert((iOffset+nAlloc)>mem5.nBlock);
+  }
+
+  /* If a mutex is required for normal operation, allocate one */
+  if( sqlite3GlobalConfig.bMemstat==0 ){
+    mem5.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void memsys5Shutdown(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  mem5.mutex = 0;
+  return;
+}
+
+#ifdef SQLITE_TEST
+/*
 ** Open the file indicated and write a log of all unfreed memory 
 ** allocations into that log.
 */
-SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
-#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3Memsys5Dump(const char *zFilename){
   FILE *out;
   int i, j, n;
+  int nMinLog;
 
   if( zFilename==0 || zFilename[0]==0 ){
     out = stdout;
@@ -12836,29 +14361,48 @@ SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
     }
   }
   memsys5Enter();
-  for(i=0; i<NSIZE; i++){
-    for(n=0, j=mem.aiFreelist[i]; j>=0; j = mem.aPool[j].u.list.next, n++){}
-    fprintf(out, "freelist items of size %d: %d\n", POW2_MIN << i, n);
-  }
-  fprintf(out, "mem.nAlloc       = %llu\n", mem.nAlloc);
-  fprintf(out, "mem.totalAlloc   = %llu\n", mem.totalAlloc);
-  fprintf(out, "mem.totalExcess  = %llu\n", mem.totalExcess);
-  fprintf(out, "mem.currentOut   = %u\n", mem.currentOut);
-  fprintf(out, "mem.currentCount = %u\n", mem.currentCount);
-  fprintf(out, "mem.maxOut       = %u\n", mem.maxOut);
-  fprintf(out, "mem.maxCount     = %u\n", mem.maxCount);
-  fprintf(out, "mem.maxRequest   = %u\n", mem.maxRequest);
-  sqlite3_mutex_leave(mem.mutex);
+  nMinLog = memsys5Log(mem5.szAtom);
+  for(i=0; i<=LOGMAX && i+nMinLog<32; i++){
+    for(n=0, j=mem5.aiFreelist[i]; j>=0; j = MEM5LINK(j)->next, n++){}
+    fprintf(out, "freelist items of size %d: %d\n", mem5.szAtom << i, n);
+  }
+  fprintf(out, "mem5.nAlloc       = %llu\n", mem5.nAlloc);
+  fprintf(out, "mem5.totalAlloc   = %llu\n", mem5.totalAlloc);
+  fprintf(out, "mem5.totalExcess  = %llu\n", mem5.totalExcess);
+  fprintf(out, "mem5.currentOut   = %u\n", mem5.currentOut);
+  fprintf(out, "mem5.currentCount = %u\n", mem5.currentCount);
+  fprintf(out, "mem5.maxOut       = %u\n", mem5.maxOut);
+  fprintf(out, "mem5.maxCount     = %u\n", mem5.maxCount);
+  fprintf(out, "mem5.maxRequest   = %u\n", mem5.maxRequest);
+  memsys5Leave();
   if( out==stdout ){
     fflush(stdout);
   }else{
     fclose(out);
   }
-#endif
 }
+#endif
 
+/*
+** This routine is the only routine in this file with external 
+** linkage. It returns a pointer to a static sqlite3_mem_methods
+** struct populated with the memsys5 methods.
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void){
+  static const sqlite3_mem_methods memsys5Methods = {
+     memsys5Malloc,
+     memsys5Free,
+     memsys5Realloc,
+     memsys5Size,
+     memsys5Roundup,
+     memsys5Init,
+     memsys5Shutdown,
+     0
+  };
+  return &memsys5Methods;
+}
 
-#endif /* !SQLITE_POW2_MEMORY_SIZE */
+#endif /* SQLITE_ENABLE_MEMSYS5 */
 
 /************** End of mem5.c ************************************************/
 /************** Begin file mutex.c *******************************************/
@@ -12875,22 +14419,218 @@ SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
 *************************************************************************
 ** This file contains the C functions that implement mutexes.
 **
-** The implementation in this file does not provide any mutual
+** This file contains code that is common across all mutex implementations.
+
+**
+** $Id: mutex.c,v 1.31 2009/07/16 18:21:18 drh Exp $
+*/
+
+#if defined(SQLITE_DEBUG) && !defined(SQLITE_MUTEX_OMIT)
+/*
+** For debugging purposes, record when the mutex subsystem is initialized
+** and uninitialized so that we can assert() if there is an attempt to
+** allocate a mutex while the system is uninitialized.
+*/
+static SQLITE_WSD int mutexIsInit = 0;
+#endif /* SQLITE_DEBUG */
+
+
+#ifndef SQLITE_MUTEX_OMIT
+/*
+** Initialize the mutex system.
+*/
+SQLITE_PRIVATE int sqlite3MutexInit(void){ 
+  int rc = SQLITE_OK;
+  if( sqlite3GlobalConfig.bCoreMutex ){
+    if( !sqlite3GlobalConfig.mutex.xMutexAlloc ){
+      /* If the xMutexAlloc method has not been set, then the user did not
+      ** install a mutex implementation via sqlite3_config() prior to 
+      ** sqlite3_initialize() being called. This block copies pointers to
+      ** the default implementation into the sqlite3GlobalConfig structure.
+      */
+      sqlite3_mutex_methods *pFrom = sqlite3DefaultMutex();
+      sqlite3_mutex_methods *pTo = &sqlite3GlobalConfig.mutex;
+
+      memcpy(pTo, pFrom, offsetof(sqlite3_mutex_methods, xMutexAlloc));
+      memcpy(&pTo->xMutexFree, &pFrom->xMutexFree,
+             sizeof(*pTo) - offsetof(sqlite3_mutex_methods, xMutexFree));
+      pTo->xMutexAlloc = pFrom->xMutexAlloc;
+    }
+    rc = sqlite3GlobalConfig.mutex.xMutexInit();
+  }
+
+#ifdef SQLITE_DEBUG
+  GLOBAL(int, mutexIsInit) = 1;
+#endif
+
+  return rc;
+}
+
+/*
+** Shutdown the mutex system. This call frees resources allocated by
+** sqlite3MutexInit().
+*/
+SQLITE_PRIVATE int sqlite3MutexEnd(void){
+  int rc = SQLITE_OK;
+  if( sqlite3GlobalConfig.mutex.xMutexEnd ){
+    rc = sqlite3GlobalConfig.mutex.xMutexEnd();
+  }
+
+#ifdef SQLITE_DEBUG
+  GLOBAL(int, mutexIsInit) = 0;
+#endif
+
+  return rc;
+}
+
+/*
+** Retrieve a pointer to a static mutex or allocate a new dynamic one.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MutexAlloc(int id){
+  if( !sqlite3GlobalConfig.bCoreMutex ){
+    return 0;
+  }
+  assert( GLOBAL(int, mutexIsInit) );
+  return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+/*
+** Free a dynamic mutex.
+*/
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
+  if( p ){
+    sqlite3GlobalConfig.mutex.xMutexFree(p);
+  }
+}
+
+/*
+** Obtain the mutex p. If some other thread already has the mutex, block
+** until it can be obtained.
+*/
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
+  if( p ){
+    sqlite3GlobalConfig.mutex.xMutexEnter(p);
+  }
+}
+
+/*
+** Obtain the mutex p. If successful, return SQLITE_OK. Otherwise, if another
+** thread holds the mutex and it cannot be obtained, return SQLITE_BUSY.
+*/
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+  int rc = SQLITE_OK;
+  if( p ){
+    return sqlite3GlobalConfig.mutex.xMutexTry(p);
+  }
+  return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was previously
+** entered by the same thread.  The behavior is undefined if the mutex 
+** is not currently entered. If a NULL pointer is passed as an argument
+** this function is a no-op.
+*/
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
+  if( p ){
+    sqlite3GlobalConfig.mutex.xMutexLeave(p);
+  }
+}
+
+#ifndef NDEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
+  return p==0 || sqlite3GlobalConfig.mutex.xMutexHeld(p);
+}
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
+  return p==0 || sqlite3GlobalConfig.mutex.xMutexNotheld(p);
+}
+#endif
+
+#endif /* SQLITE_MUTEX_OMIT */
+
+/************** End of mutex.c ***********************************************/
+/************** Begin file mutex_noop.c **************************************/
+/*
+** 2008 October 07
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes.
+**
+** This implementation in this file does not provide any mutual
 ** exclusion and is thus suitable for use only in applications
-** that use SQLite in a single thread.  But this implementation
-** does do a lot of error checking on mutexes to make sure they
-** are called correctly and at appropriate times.  Hence, this
-** implementation is suitable for testing.
-** debugging purposes
+** that use SQLite in a single thread.  The routines defined
+** here are place-holders.  Applications can substitute working
+** mutex routines at start-time using the
+**
+**     sqlite3_config(SQLITE_CONFIG_MUTEX,...)
+**
+** interface.
+**
+** If compiled with SQLITE_DEBUG, then additional logic is inserted
+** that does error checking on mutexes to make sure they are being
+** called correctly.
 **
-** $Id: mutex.c,v 1.17 2008/03/26 18:34:43 danielk1977 Exp $
+** $Id: mutex_noop.c,v 1.3 2008/12/05 17:17:08 drh Exp $
 */
 
-#ifdef SQLITE_MUTEX_NOOP_DEBUG
+
+#if defined(SQLITE_MUTEX_NOOP) && !defined(SQLITE_DEBUG)
 /*
-** In this implementation, mutexes do not provide any mutual exclusion.
-** But the error checking is provided.  This implementation is useful
-** for test purposes.
+** Stub routines for all mutex methods.
+**
+** This routines provide no mutual exclusion or error checking.
+*/
+static int noopMutexHeld(sqlite3_mutex *p){ return 1; }
+static int noopMutexNotheld(sqlite3_mutex *p){ return 1; }
+static int noopMutexInit(void){ return SQLITE_OK; }
+static int noopMutexEnd(void){ return SQLITE_OK; }
+static sqlite3_mutex *noopMutexAlloc(int id){ return (sqlite3_mutex*)8; }
+static void noopMutexFree(sqlite3_mutex *p){ return; }
+static void noopMutexEnter(sqlite3_mutex *p){ return; }
+static int noopMutexTry(sqlite3_mutex *p){ return SQLITE_OK; }
+static void noopMutexLeave(sqlite3_mutex *p){ return; }
+
+SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
+  static sqlite3_mutex_methods sMutex = {
+    noopMutexInit,
+    noopMutexEnd,
+    noopMutexAlloc,
+    noopMutexFree,
+    noopMutexEnter,
+    noopMutexTry,
+    noopMutexLeave,
+
+    noopMutexHeld,
+    noopMutexNotheld
+  };
+
+  return &sMutex;
+}
+#endif /* defined(SQLITE_MUTEX_NOOP) && !defined(SQLITE_DEBUG) */
+
+#if defined(SQLITE_MUTEX_NOOP) && defined(SQLITE_DEBUG)
+/*
+** In this implementation, error checking is provided for testing
+** and debugging purposes.  The mutexes still do not provide any
+** mutual exclusion.
 */
 
 /*
@@ -12902,17 +14642,34 @@ struct sqlite3_mutex {
 };
 
 /*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+static int debugMutexHeld(sqlite3_mutex *p){
+  return p==0 || p->cnt>0;
+}
+static int debugMutexNotheld(sqlite3_mutex *p){
+  return p==0 || p->cnt==0;
+}
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int debugMutexInit(void){ return SQLITE_OK; }
+static int debugMutexEnd(void){ return SQLITE_OK; }
+
+/*
 ** The sqlite3_mutex_alloc() routine allocates a new
 ** mutex and returns a pointer to it.  If it returns NULL
 ** that means that a mutex could not be allocated. 
 */
-SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
+static sqlite3_mutex *debugMutexAlloc(int id){
   static sqlite3_mutex aStatic[6];
   sqlite3_mutex *pNew = 0;
   switch( id ){
     case SQLITE_MUTEX_FAST:
     case SQLITE_MUTEX_RECURSIVE: {
-      pNew = sqlite3_malloc(sizeof(*pNew));
+      pNew = sqlite3Malloc(sizeof(*pNew));
       if( pNew ){
         pNew->id = id;
         pNew->cnt = 0;
@@ -12921,7 +14678,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
     }
     default: {
       assert( id-2 >= 0 );
-      assert( id-2 < sizeof(aStatic)/sizeof(aStatic[0]) );
+      assert( id-2 < (int)(sizeof(aStatic)/sizeof(aStatic[0])) );
       pNew = &aStatic[id-2];
       pNew->id = id;
       break;
@@ -12933,8 +14690,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
 /*
 ** This routine deallocates a previously allocated mutex.
 */
-SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
-  assert( p );
+static void debugMutexFree(sqlite3_mutex *p){
   assert( p->cnt==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
   sqlite3_free(p);
@@ -12951,14 +14707,12 @@ SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
 ** can enter.  If the same thread tries to enter any other kind of mutex
 ** more than once, the behavior is undefined.
 */
-SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+static void debugMutexEnter(sqlite3_mutex *p){
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
   p->cnt++;
 }
-SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+static int debugMutexTry(sqlite3_mutex *p){
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
   p->cnt++;
   return SQLITE_OK;
 }
@@ -12969,26 +14723,31 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
 ** is undefined if the mutex is not currently entered or
 ** is not currently allocated.  SQLite will never do either.
 */
-SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
-  assert( p );
-  assert( sqlite3_mutex_held(p) );
+static void debugMutexLeave(sqlite3_mutex *p){
+  assert( debugMutexHeld(p) );
   p->cnt--;
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
 }
 
-/*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use inside assert() statements.
-*/
-SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
-  return p==0 || p->cnt>0;
-}
-SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
-  return p==0 || p->cnt==0;
+SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
+  static sqlite3_mutex_methods sMutex = {
+    debugMutexInit,
+    debugMutexEnd,
+    debugMutexAlloc,
+    debugMutexFree,
+    debugMutexEnter,
+    debugMutexTry,
+    debugMutexLeave,
+
+    debugMutexHeld,
+    debugMutexNotheld
+  };
+
+  return &sMutex;
 }
-#endif /* SQLITE_MUTEX_NOOP_DEBUG */
+#endif /* defined(SQLITE_MUTEX_NOOP) && defined(SQLITE_DEBUG) */
 
-/************** End of mutex.c ***********************************************/
+/************** End of mutex_noop.c ******************************************/
 /************** Begin file mutex_os2.c ***************************************/
 /*
 ** 2007 August 28
@@ -13003,7 +14762,7 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
 *************************************************************************
 ** This file contains the C functions that implement mutexes for OS/2
 **
-** $Id: mutex_os2.c,v 1.6 2008/03/26 18:34:43 danielk1977 Exp $
+** $Id: mutex_os2.c,v 1.11 2008/11/22 19:50:54 pweilbacher Exp $
 */
 
 /*
@@ -13031,6 +14790,12 @@ struct sqlite3_mutex {
 #define OS2_MUTEX_INITIALIZER   0,0,0,0
 
 /*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int os2MutexInit(void){ return SQLITE_OK; }
+static int os2MutexEnd(void){ return SQLITE_OK; }
+
+/*
 ** The sqlite3_mutex_alloc() routine allocates a new
 ** mutex and returns a pointer to it.  If it returns NULL
 ** that means that a mutex could not be allocated. 
@@ -13069,7 +14834,7 @@ struct sqlite3_mutex {
 ** mutex types, the same mutex is returned on every call that has
 ** the same type number.
 */
-SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
+static sqlite3_mutex *os2MutexAlloc(int iType){
   sqlite3_mutex *p = NULL;
   switch( iType ){
     case SQLITE_MUTEX_FAST:
@@ -13107,7 +14872,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
           mutex = 0;
           rc = DosCreateMutexSem( name, &mutex, 0, FALSE);
           if( rc == NO_ERROR ){
-            int i;
+            unsigned int i;
             if( !isInit ){
               for( i = 0; i < sizeof(staticMutexes)/sizeof(staticMutexes[0]); i++ ){
                 DosCreateMutexSem( 0, &staticMutexes[i].mutex, 0, FALSE );
@@ -13137,8 +14902,8 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
 ** This routine deallocates a previously allocated mutex.
 ** SQLite is careful to deallocate every mutex that it allocates.
 */
-SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
-  assert( p );
+static void os2MutexFree(sqlite3_mutex *p){
+  if( p==0 ) return;
   assert( p->nRef==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
   DosCloseMutexSem( p->mutex );
@@ -13156,24 +14921,24 @@ SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
 ** can enter.  If the same thread tries to enter any other kind of mutex
 ** more than once, the behavior is undefined.
 */
-SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
+static void os2MutexEnter(sqlite3_mutex *p){
   TID tid;
   PID holder1;
   ULONG holder2;
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+  if( p==0 ) return;
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
   DosRequestMutexSem(p->mutex, SEM_INDEFINITE_WAIT);
   DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
   p->owner = tid;
   p->nRef++;
 }
-SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+static int os2MutexTry(sqlite3_mutex *p){
   int rc;
   TID tid;
   PID holder1;
   ULONG holder2;
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+  if( p==0 ) return SQLITE_OK;
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
   if( DosRequestMutexSem(p->mutex, SEM_IMMEDIATE_RETURN) == NO_ERROR) {
     DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
     p->owner = tid;
@@ -13192,10 +14957,11 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
 ** is undefined if the mutex is not currently entered or
 ** is not currently allocated.  SQLite will never do either.
 */
-SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
+static void os2MutexLeave(sqlite3_mutex *p){
   TID tid;
   PID holder1;
   ULONG holder2;
+  if( p==0 ) return;
   assert( p->nRef>0 );
   DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
   assert( p->owner==tid );
@@ -13204,11 +14970,12 @@ SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
   DosReleaseMutexSem(p->mutex);
 }
 
+#ifdef SQLITE_DEBUG
 /*
 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
 ** intended for use inside assert() statements.
 */
-SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
+static int os2MutexHeld(sqlite3_mutex *p){
   TID tid;
   PID pid;
   ULONG ulCount;
@@ -13221,7 +14988,7 @@ SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
   }
   return p==0 || (p->nRef!=0 && p->owner==tid);
 }
-SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
+static int os2MutexNotheld(sqlite3_mutex *p){
   TID tid;
   PID pid;
   ULONG ulCount;
@@ -13234,6 +15001,25 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
   }
   return p==0 || p->nRef==0 || p->owner!=tid;
 }
+#endif
+
+SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
+  static sqlite3_mutex_methods sMutex = {
+    os2MutexInit,
+    os2MutexEnd,
+    os2MutexAlloc,
+    os2MutexFree,
+    os2MutexEnter,
+    os2MutexTry,
+    os2MutexLeave,
+#ifdef SQLITE_DEBUG
+    os2MutexHeld,
+    os2MutexNotheld
+#endif
+  };
+
+  return &sMutex;
+}
 #endif /* SQLITE_MUTEX_OS2 */
 
 /************** End of mutex_os2.c *******************************************/
@@ -13251,7 +15037,7 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
 *************************************************************************
 ** This file contains the C functions that implement mutexes for pthreads
 **
-** $Id: mutex_unix.c,v 1.7 2008/03/29 12:47:27 rse Exp $
+** $Id: mutex_unix.c,v 1.16 2008/12/08 18:19:18 drh Exp $
 */
 
 /*
@@ -13285,6 +15071,37 @@ struct sqlite3_mutex {
 #endif
 
 /*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements.  On some platforms,
+** there might be race conditions that can cause these routines to
+** deliver incorrect results.  In particular, if pthread_equal() is
+** not an atomic operation, then these routines might delivery
+** incorrect results.  On most platforms, pthread_equal() is a 
+** comparison of two integers and is therefore atomic.  But we are
+** told that HPUX is not such a platform.  If so, then these routines
+** will not always work correctly on HPUX.
+**
+** On those platforms where pthread_equal() is not atomic, SQLite
+** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
+** make sure no assert() statements are evaluated and hence these
+** routines are never called.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_DEBUG)
+static int pthreadMutexHeld(sqlite3_mutex *p){
+  return (p->nRef!=0 && pthread_equal(p->owner, pthread_self()));
+}
+static int pthreadMutexNotheld(sqlite3_mutex *p){
+  return p->nRef==0 || pthread_equal(p->owner, pthread_self())==0;
+}
+#endif
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int pthreadMutexInit(void){ return SQLITE_OK; }
+static int pthreadMutexEnd(void){ return SQLITE_OK; }
+
+/*
 ** The sqlite3_mutex_alloc() routine allocates a new
 ** mutex and returns a pointer to it.  If it returns NULL
 ** that means that a mutex could not be allocated.  SQLite
@@ -13299,6 +15116,7 @@ struct sqlite3_mutex {
 ** <li>  SQLITE_MUTEX_STATIC_MEM2
 ** <li>  SQLITE_MUTEX_STATIC_PRNG
 ** <li>  SQLITE_MUTEX_STATIC_LRU
+** <li>  SQLITE_MUTEX_STATIC_LRU2
 ** </ul>
 **
 ** The first two constants cause sqlite3_mutex_alloc() to create
@@ -13312,7 +15130,7 @@ struct sqlite3_mutex {
 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
 **
 ** The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex.  Three static mutexes are
+** a pointer to a static preexisting mutex.  Six static mutexes are
 ** used by the current version of SQLite.  Future versions of SQLite
 ** may add additional static mutexes.  Static mutexes are for internal
 ** use by SQLite only.  Applications that use SQLite mutexes should
@@ -13325,7 +15143,7 @@ struct sqlite3_mutex {
 ** mutex types, the same mutex is returned on every call that has
 ** the same type number.
 */
-SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
+static sqlite3_mutex *pthreadMutexAlloc(int iType){
   static sqlite3_mutex staticMutexes[] = {
     SQLITE3_MUTEX_INITIALIZER,
     SQLITE3_MUTEX_INITIALIZER,
@@ -13365,7 +15183,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
     }
     default: {
       assert( iType-2 >= 0 );
-      assert( iType-2 < sizeof(staticMutexes)/sizeof(staticMutexes[0]) );
+      assert( iType-2 < ArraySize(staticMutexes) );
       p = &staticMutexes[iType-2];
       p->id = iType;
       break;
@@ -13380,8 +15198,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
 ** allocated mutex.  SQLite is careful to deallocate every
 ** mutex that it allocates.
 */
-SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
-  assert( p );
+static void pthreadMutexFree(sqlite3_mutex *p){
   assert( p->nRef==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
   pthread_mutex_destroy(&p->mutex);
@@ -13399,9 +15216,8 @@ SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
 ** can enter.  If the same thread tries to enter any other kind of mutex
 ** more than once, the behavior is undefined.
 */
-SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+static void pthreadMutexEnter(sqlite3_mutex *p){
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
 
 #ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
   /* If recursive mutexes are not available, then we have to grow
@@ -13439,10 +15255,9 @@ SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
   }
 #endif
 }
-SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+static int pthreadMutexTry(sqlite3_mutex *p){
   int rc;
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
 
 #ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
   /* If recursive mutexes are not available, then we have to grow
@@ -13460,7 +15275,7 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
     if( p->nRef>0 && pthread_equal(p->owner, self) ){
       p->nRef++;
       rc = SQLITE_OK;
-    }else if( pthread_mutex_lock(&p->mutex)==0 ){
+    }else if( pthread_mutex_trylock(&p->mutex)==0 ){
       assert( p->nRef==0 );
       p->owner = self;
       p->nRef = 1;
@@ -13495,9 +15310,8 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
 ** is undefined if the mutex is not currently entered or
 ** is not currently allocated.  SQLite will never do either.
 */
-SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
-  assert( p );
-  assert( sqlite3_mutex_held(p) );
+static void pthreadMutexLeave(sqlite3_mutex *p){
+  assert( pthreadMutexHeld(p) );
   p->nRef--;
   assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
 
@@ -13516,30 +15330,27 @@ SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
 #endif
 }
 
-/*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use only inside assert() statements.  On some platforms,
-** there might be race conditions that can cause these routines to
-** deliver incorrect results.  In particular, if pthread_equal() is
-** not an atomic operation, then these routines might delivery
-** incorrect results.  On most platforms, pthread_equal() is a 
-** comparison of two integers and is therefore atomic.  But we are
-** told that HPUX is not such a platform.  If so, then these routines
-** will not always work correctly on HPUX.
-**
-** On those platforms where pthread_equal() is not atomic, SQLite
-** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
-** make sure no assert() statements are evaluated and hence these
-** routines are never called.
-*/
-#ifndef NDEBUG
-SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
-  return p==0 || (p->nRef!=0 && pthread_equal(p->owner, pthread_self()));
-}
-SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
-  return p==0 || p->nRef==0 || pthread_equal(p->owner, pthread_self())==0;
-}
+SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
+  static sqlite3_mutex_methods sMutex = {
+    pthreadMutexInit,
+    pthreadMutexEnd,
+    pthreadMutexAlloc,
+    pthreadMutexFree,
+    pthreadMutexEnter,
+    pthreadMutexTry,
+    pthreadMutexLeave,
+#ifdef SQLITE_DEBUG
+    pthreadMutexHeld,
+    pthreadMutexNotheld
+#else
+    0,
+    0
 #endif
+  };
+
+  return &sMutex;
+}
+
 #endif /* SQLITE_MUTEX_PTHREAD */
 
 /************** End of mutex_unix.c ******************************************/
@@ -13557,7 +15368,7 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
 *************************************************************************
 ** This file contains the C functions that implement mutexes for win32
 **
-** $Id: mutex_w32.c,v 1.6 2008/03/26 18:34:43 danielk1977 Exp $
+** $Id: mutex_w32.c,v 1.18 2009/08/10 03:23:21 shane Exp $
 */
 
 /*
@@ -13586,8 +15397,15 @@ struct sqlite3_mutex {
 ** this routine is used to determine if the host is Win95/98/ME or
 ** WinNT/2K/XP so that we will know whether or not we can safely call
 ** the LockFileEx() API.
+**
+** mutexIsNT() is only used for the TryEnterCriticalSection() API call,
+** which is only available if your application was compiled with 
+** _WIN32_WINNT defined to a value >= 0x0400.  Currently, the only
+** call to TryEnterCriticalSection() is #ifdef'ed out, so #ifdef 
+** this out as well.
 */
-#if OS_WINCE
+#if 0
+#if SQLITE_OS_WINCE
 # define mutexIsNT()  (1)
 #else
   static int mutexIsNT(void){
@@ -13600,8 +15418,66 @@ struct sqlite3_mutex {
     }
     return osType==2;
   }
-#endif /* OS_WINCE */
+#endif /* SQLITE_OS_WINCE */
+#endif
+
+#ifdef SQLITE_DEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements.
+*/
+static int winMutexHeld(sqlite3_mutex *p){
+  return p->nRef!=0 && p->owner==GetCurrentThreadId();
+}
+static int winMutexNotheld(sqlite3_mutex *p){
+  return p->nRef==0 || p->owner!=GetCurrentThreadId();
+}
+#endif
+
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static sqlite3_mutex winMutex_staticMutexes[6];
+static int winMutex_isInit = 0;
+/* As winMutexInit() and winMutexEnd() are called as part
+** of the sqlite3_initialize and sqlite3_shutdown()
+** processing, the "interlocked" magic is probably not
+** strictly necessary.
+*/
+static long winMutex_lock = 0;
+
+static int winMutexInit(void){ 
+  /* The first to increment to 1 does actual initialization */
+  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
+    int i;
+    for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
+      InitializeCriticalSection(&winMutex_staticMutexes[i].mutex);
+    }
+    winMutex_isInit = 1;
+  }else{
+    /* Someone else is in the process of initing the static mutexes */
+    while( !winMutex_isInit ){
+      Sleep(1);
+    }
+  }
+  return SQLITE_OK; 
+}
 
+static int winMutexEnd(void){ 
+  /* The first to decrement to 0 does actual shutdown 
+  ** (which should be the last to shutdown.) */
+  if( InterlockedCompareExchange(&winMutex_lock, 0, 1)==1 ){
+    if( winMutex_isInit==1 ){
+      int i;
+      for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
+        DeleteCriticalSection(&winMutex_staticMutexes[i].mutex);
+      }
+      winMutex_isInit = 0;
+    }
+  }
+  return SQLITE_OK; 
+}
 
 /*
 ** The sqlite3_mutex_alloc() routine allocates a new
@@ -13611,11 +15487,14 @@ struct sqlite3_mutex {
 ** to sqlite3_mutex_alloc() is one of these integer constants:
 **
 ** <ul>
-** <li>  SQLITE_MUTEX_FAST               0
-** <li>  SQLITE_MUTEX_RECURSIVE          1
-** <li>  SQLITE_MUTEX_STATIC_MASTER      2
-** <li>  SQLITE_MUTEX_STATIC_MEM         3
-** <li>  SQLITE_MUTEX_STATIC_PRNG        4
+** <li>  SQLITE_MUTEX_FAST
+** <li>  SQLITE_MUTEX_RECURSIVE
+** <li>  SQLITE_MUTEX_STATIC_MASTER
+** <li>  SQLITE_MUTEX_STATIC_MEM
+** <li>  SQLITE_MUTEX_STATIC_MEM2
+** <li>  SQLITE_MUTEX_STATIC_PRNG
+** <li>  SQLITE_MUTEX_STATIC_LRU
+** <li>  SQLITE_MUTEX_STATIC_LRU2
 ** </ul>
 **
 ** The first two constants cause sqlite3_mutex_alloc() to create
@@ -13629,7 +15508,7 @@ struct sqlite3_mutex {
 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
 **
 ** The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex.  Three static mutexes are
+** a pointer to a static preexisting mutex.  Six static mutexes are
 ** used by the current version of SQLite.  Future versions of SQLite
 ** may add additional static mutexes.  Static mutexes are for internal
 ** use by SQLite only.  Applications that use SQLite mutexes should
@@ -13642,37 +15521,24 @@ struct sqlite3_mutex {
 ** mutex types, the same mutex is returned on every call that has
 ** the same type number.
 */
-SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
+static sqlite3_mutex *winMutexAlloc(int iType){
   sqlite3_mutex *p;
 
   switch( iType ){
     case SQLITE_MUTEX_FAST:
     case SQLITE_MUTEX_RECURSIVE: {
       p = sqlite3MallocZero( sizeof(*p) );
-      if( p ){
+      if( p ){  
         p->id = iType;
         InitializeCriticalSection(&p->mutex);
       }
       break;
     }
     default: {
-      static sqlite3_mutex staticMutexes[6];
-      static int isInit = 0;
-      while( !isInit ){
-        static long lock = 0;
-        if( InterlockedIncrement(&lock)==1 ){
-          int i;
-          for(i=0; i<sizeof(staticMutexes)/sizeof(staticMutexes[0]); i++){
-            InitializeCriticalSection(&staticMutexes[i].mutex);
-          }
-          isInit = 1;
-        }else{
-          Sleep(1);
-        }
-      }
+      assert( winMutex_isInit==1 );
       assert( iType-2 >= 0 );
-      assert( iType-2 < sizeof(staticMutexes)/sizeof(staticMutexes[0]) );
-      p = &staticMutexes[iType-2];
+      assert( iType-2 < ArraySize(winMutex_staticMutexes) );
+      p = &winMutex_staticMutexes[iType-2];
       p->id = iType;
       break;
     }
@@ -13686,7 +15552,7 @@ SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int iType){
 ** allocated mutex.  SQLite is careful to deallocate every
 ** mutex that it allocates.
 */
-SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
+static void winMutexFree(sqlite3_mutex *p){
   assert( p );
   assert( p->nRef==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
@@ -13705,17 +15571,15 @@ SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
 ** can enter.  If the same thread tries to enter any other kind of mutex
 ** more than once, the behavior is undefined.
 */
-SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+static void winMutexEnter(sqlite3_mutex *p){
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld(p) );
   EnterCriticalSection(&p->mutex);
   p->owner = GetCurrentThreadId(); 
   p->nRef++;
 }
-SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+static int winMutexTry(sqlite3_mutex *p){
   int rc = SQLITE_BUSY;
-  assert( p );
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || sqlite3_mutex_notheld(p) );
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld(p) );
   /*
   ** The sqlite3_mutex_try() routine is very rarely used, and when it
   ** is used it is merely an optimization.  So it is OK for it to always
@@ -13733,6 +15597,8 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
     p->nRef++;
     rc = SQLITE_OK;
   }
+#else
+  UNUSED_PARAMETER(p);
 #endif
   return rc;
 }
@@ -13743,7 +15609,7 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
 ** is undefined if the mutex is not currently entered or
 ** is not currently allocated.  SQLite will never do either.
 */
-SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
+static void winMutexLeave(sqlite3_mutex *p){
   assert( p->nRef>0 );
   assert( p->owner==GetCurrentThreadId() );
   p->nRef--;
@@ -13751,15 +15617,25 @@ SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
   LeaveCriticalSection(&p->mutex);
 }
 
-/*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use only inside assert() statements.
-*/
-SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
-  return p==0 || (p->nRef!=0 && p->owner==GetCurrentThreadId());
-}
-SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
-  return p==0 || p->nRef==0 || p->owner!=GetCurrentThreadId();
+SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
+  static sqlite3_mutex_methods sMutex = {
+    winMutexInit,
+    winMutexEnd,
+    winMutexAlloc,
+    winMutexFree,
+    winMutexEnter,
+    winMutexTry,
+    winMutexLeave,
+#ifdef SQLITE_DEBUG
+    winMutexHeld,
+    winMutexNotheld
+#else
+    0,
+    0
+#endif
+  };
+
+  return &sMutex;
 }
 #endif /* SQLITE_MUTEX_W32 */
 
@@ -13776,10 +15652,10 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** Memory allocation functions used throughout sqlite.
 **
+** Memory allocation functions used throughout sqlite.
 **
-** $Id: malloc.c,v 1.15 2008/03/26 18:34:43 danielk1977 Exp $
+** $Id: malloc.c,v 1.66 2009/07/17 11:44:07 drh Exp $
 */
 
 /*
@@ -13789,15 +15665,16 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
 */
 static void softHeapLimitEnforcer(
   void *NotUsed, 
-  sqlite3_int64 inUse,
+  sqlite3_int64 NotUsed2,
   int allocSize
 ){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
   sqlite3_release_memory(allocSize);
 }
 
 /*
-** Set the soft heap-size limit for the current thread. Passing a
-** zero or negative value indicates no limit.
+** Set the soft heap-size limit for the library. Passing a zero or 
+** negative value indicates no limit.
 */
 SQLITE_API void sqlite3_soft_heap_limit(int n){
   sqlite3_uint64 iLimit;
@@ -13807,36 +15684,487 @@ SQLITE_API void sqlite3_soft_heap_limit(int n){
   }else{
     iLimit = n;
   }
+#ifndef SQLITE_OMIT_AUTOINIT
+  sqlite3_initialize();
+#endif
   if( iLimit>0 ){
-    sqlite3_memory_alarm(softHeapLimitEnforcer, 0, iLimit);
+    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, iLimit);
   }else{
-    sqlite3_memory_alarm(0, 0, 0);
+    sqlite3MemoryAlarm(0, 0, 0);
   }
-  overage = sqlite3_memory_used() - n;
+  overage = (int)(sqlite3_memory_used() - (i64)n);
   if( overage>0 ){
     sqlite3_release_memory(overage);
   }
 }
 
 /*
-** Release memory held by SQLite instances created by the current thread.
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
 */
 SQLITE_API int sqlite3_release_memory(int n){
 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  int nRet = sqlite3VdbeReleaseMemory(n);
-  nRet += sqlite3PagerReleaseMemory(n-nRet);
+  int nRet = 0;
+#if 0
+  nRet += sqlite3VdbeReleaseMemory(n);
+#endif
+  nRet += sqlite3PcacheReleaseMemory(n-nRet);
   return nRet;
 #else
+  UNUSED_PARAMETER(n);
   return SQLITE_OK;
 #endif
 }
 
+/*
+** State information local to the memory allocation subsystem.
+*/
+static SQLITE_WSD struct Mem0Global {
+  /* Number of free pages for scratch and page-cache memory */
+  u32 nScratchFree;
+  u32 nPageFree;
+
+  sqlite3_mutex *mutex;         /* Mutex to serialize access */
+
+  /*
+  ** The alarm callback and its arguments.  The mem0.mutex lock will
+  ** be held while the callback is running.  Recursive calls into
+  ** the memory subsystem are allowed, but no new callbacks will be
+  ** issued.
+  */
+  sqlite3_int64 alarmThreshold;
+  void (*alarmCallback)(void*, sqlite3_int64,int);
+  void *alarmArg;
+
+  /*
+  ** Pointers to the end of sqlite3GlobalConfig.pScratch and
+  ** sqlite3GlobalConfig.pPage to a block of memory that records
+  ** which pages are available.
+  */
+  u32 *aScratchFree;
+  u32 *aPageFree;
+} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
+
+/*
+** Initialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE int sqlite3MallocInit(void){
+  if( sqlite3GlobalConfig.m.xMalloc==0 ){
+    sqlite3MemSetDefault();
+  }
+  memset(&mem0, 0, sizeof(mem0));
+  if( sqlite3GlobalConfig.bCoreMutex ){
+    mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+  }
+  if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
+      && sqlite3GlobalConfig.nScratch>=0 ){
+    int i;
+    sqlite3GlobalConfig.szScratch = ROUNDDOWN8(sqlite3GlobalConfig.szScratch-4);
+    mem0.aScratchFree = (u32*)&((char*)sqlite3GlobalConfig.pScratch)
+                  [sqlite3GlobalConfig.szScratch*sqlite3GlobalConfig.nScratch];
+    for(i=0; i<sqlite3GlobalConfig.nScratch; i++){ mem0.aScratchFree[i] = i; }
+    mem0.nScratchFree = sqlite3GlobalConfig.nScratch;
+  }else{
+    sqlite3GlobalConfig.pScratch = 0;
+    sqlite3GlobalConfig.szScratch = 0;
+  }
+  if( sqlite3GlobalConfig.pPage && sqlite3GlobalConfig.szPage>=512
+      && sqlite3GlobalConfig.nPage>=1 ){
+    int i;
+    int overhead;
+    int sz = ROUNDDOWN8(sqlite3GlobalConfig.szPage);
+    int n = sqlite3GlobalConfig.nPage;
+    overhead = (4*n + sz - 1)/sz;
+    sqlite3GlobalConfig.nPage -= overhead;
+    mem0.aPageFree = (u32*)&((char*)sqlite3GlobalConfig.pPage)
+                  [sqlite3GlobalConfig.szPage*sqlite3GlobalConfig.nPage];
+    for(i=0; i<sqlite3GlobalConfig.nPage; i++){ mem0.aPageFree[i] = i; }
+    mem0.nPageFree = sqlite3GlobalConfig.nPage;
+  }else{
+    sqlite3GlobalConfig.pPage = 0;
+    sqlite3GlobalConfig.szPage = 0;
+  }
+  return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE void sqlite3MallocEnd(void){
+  if( sqlite3GlobalConfig.m.xShutdown ){
+    sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData);
+  }
+  memset(&mem0, 0, sizeof(mem0));
+}
+
+/*
+** Return the amount of memory currently checked out.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
+  int n, mx;
+  sqlite3_int64 res;
+  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, 0);
+  res = (sqlite3_int64)n;  /* Work around bug in Borland C. Ticket #3216 */
+  return res;
+}
+
+/*
+** Return the maximum amount of memory that has ever been
+** checked out since either the beginning of this process
+** or since the most recent reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
+  int n, mx;
+  sqlite3_int64 res;
+  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, resetFlag);
+  res = (sqlite3_int64)mx;  /* Work around bug in Borland C. Ticket #3216 */
+  return res;
+}
+
+/*
+** Change the alarm callback
+*/
+SQLITE_PRIVATE int sqlite3MemoryAlarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
+  mem0.alarmThreshold = iThreshold;
+  sqlite3_mutex_leave(mem0.mutex);
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface.  Internal/core SQLite code
+** should call sqlite3MemoryAlarm.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
+}
+#endif
+
+/*
+** Trigger the alarm 
+*/
+static void sqlite3MallocAlarm(int nByte){
+  void (*xCallback)(void*,sqlite3_int64,int);
+  sqlite3_int64 nowUsed;
+  void *pArg;
+  if( mem0.alarmCallback==0 ) return;
+  xCallback = mem0.alarmCallback;
+  nowUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+  pArg = mem0.alarmArg;
+  mem0.alarmCallback = 0;
+  sqlite3_mutex_leave(mem0.mutex);
+  xCallback(pArg, nowUsed, nByte);
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
+}
+
+/*
+** Do a memory allocation with statistics and alarms.  Assume the
+** lock is already held.
+*/
+static int mallocWithAlarm(int n, void **pp){
+  int nFull;
+  void *p;
+  assert( sqlite3_mutex_held(mem0.mutex) );
+  nFull = sqlite3GlobalConfig.m.xRoundup(n);
+  sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n);
+  if( mem0.alarmCallback!=0 ){
+    int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+    if( nUsed+nFull >= mem0.alarmThreshold ){
+      sqlite3MallocAlarm(nFull);
+    }
+  }
+  p = sqlite3GlobalConfig.m.xMalloc(nFull);
+  if( p==0 && mem0.alarmCallback ){
+    sqlite3MallocAlarm(nFull);
+    p = sqlite3GlobalConfig.m.xMalloc(nFull);
+  }
+  if( p ){
+    nFull = sqlite3MallocSize(p);
+    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
+  }
+  *pp = p;
+  return nFull;
+}
+
+/*
+** Allocate memory.  This routine is like sqlite3_malloc() except that it
+** assumes the memory subsystem has already been initialized.
+*/
+SQLITE_PRIVATE void *sqlite3Malloc(int n){
+  void *p;
+  if( n<=0 || n>=0x7fffff00 ){
+    /* A memory allocation of a number of bytes which is near the maximum
+    ** signed integer value might cause an integer overflow inside of the
+    ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
+    ** 255 bytes of overhead.  SQLite itself will never use anything near
+    ** this amount.  The only way to reach the limit is with sqlite3_malloc() */
+    p = 0;
+  }else if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    mallocWithAlarm(n, &p);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    p = sqlite3GlobalConfig.m.xMalloc(n);
+  }
+  return p;
+}
+
+/*
+** This version of the memory allocation is for use by the application.
+** First make sure the memory subsystem is initialized, then do the
+** allocation.
+*/
+SQLITE_API void *sqlite3_malloc(int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  return sqlite3Malloc(n);
+}
+
+/*
+** Each thread may only have a single outstanding allocation from
+** xScratchMalloc().  We verify this constraint in the single-threaded
+** case by setting scratchAllocOut to 1 when an allocation
+** is outstanding clearing it when the allocation is freed.
+*/
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+static int scratchAllocOut = 0;
+#endif
+
+
+/*
+** Allocate memory that is to be used and released right away.
+** This routine is similar to alloca() in that it is not intended
+** for situations where the memory might be held long-term.  This
+** routine is intended to get memory to old large transient data
+** structures that would not normally fit on the stack of an
+** embedded processor.
+*/
+SQLITE_PRIVATE void *sqlite3ScratchMalloc(int n){
+  void *p;
+  assert( n>0 );
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+  /* Verify that no more than one scratch allocation per thread
+  ** is outstanding at one time.  (This is only checked in the
+  ** single-threaded case since checking in the multi-threaded case
+  ** would be much more complicated.) */
+  assert( scratchAllocOut==0 );
+#endif
+
+  if( sqlite3GlobalConfig.szScratch<n ){
+    goto scratch_overflow;
+  }else{  
+    sqlite3_mutex_enter(mem0.mutex);
+    if( mem0.nScratchFree==0 ){
+      sqlite3_mutex_leave(mem0.mutex);
+      goto scratch_overflow;
+    }else{
+      int i;
+      i = mem0.aScratchFree[--mem0.nScratchFree];
+      i *= sqlite3GlobalConfig.szScratch;
+      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
+      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+      sqlite3_mutex_leave(mem0.mutex);
+      p = (void*)&((char*)sqlite3GlobalConfig.pScratch)[i];
+      assert(  (((u8*)p - (u8*)0) & 7)==0 );
+    }
+  }
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+  scratchAllocOut = p!=0;
+#endif
+
+  return p;
+
+scratch_overflow:
+  if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+    n = mallocWithAlarm(n, &p);
+    if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    p = sqlite3GlobalConfig.m.xMalloc(n);
+  }
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+  scratchAllocOut = p!=0;
+#endif
+  return p;    
+}
+SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
+  if( p ){
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+    /* Verify that no more than one scratch allocation per thread
+    ** is outstanding at one time.  (This is only checked in the
+    ** single-threaded case since checking in the multi-threaded case
+    ** would be much more complicated.) */
+    assert( scratchAllocOut==1 );
+    scratchAllocOut = 0;
+#endif
+
+    if( sqlite3GlobalConfig.pScratch==0
+           || p<sqlite3GlobalConfig.pScratch
+           || p>=(void*)mem0.aScratchFree ){
+      if( sqlite3GlobalConfig.bMemstat ){
+        int iSize = sqlite3MallocSize(p);
+        sqlite3_mutex_enter(mem0.mutex);
+        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
+        sqlite3GlobalConfig.m.xFree(p);
+        sqlite3_mutex_leave(mem0.mutex);
+      }else{
+        sqlite3GlobalConfig.m.xFree(p);
+      }
+    }else{
+      int i;
+      i = (int)((u8*)p - (u8*)sqlite3GlobalConfig.pScratch);
+      i /= sqlite3GlobalConfig.szScratch;
+      assert( i>=0 && i<sqlite3GlobalConfig.nScratch );
+      sqlite3_mutex_enter(mem0.mutex);
+      assert( mem0.nScratchFree<(u32)sqlite3GlobalConfig.nScratch );
+      mem0.aScratchFree[mem0.nScratchFree++] = i;
+      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
+      sqlite3_mutex_leave(mem0.mutex);
+    }
+  }
+}
+
+/*
+** TRUE if p is a lookaside memory allocation from db
+*/
+#ifndef SQLITE_OMIT_LOOKASIDE
+static int isLookaside(sqlite3 *db, void *p){
+  return db && p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
+}
+#else
+#define isLookaside(A,B) 0
+#endif
+
+/*
+** Return the size of a memory allocation previously obtained from
+** sqlite3Malloc() or sqlite3_malloc().
+*/
+SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+  return sqlite3GlobalConfig.m.xSize(p);
+}
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  if( isLookaside(db, p) ){
+    return db->lookaside.sz;
+  }else{
+    return sqlite3GlobalConfig.m.xSize(p);
+  }
+}
+
+/*
+** Free memory previously obtained from sqlite3Malloc().
+*/
+SQLITE_API void sqlite3_free(void *p){
+  if( p==0 ) return;
+  if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
+    sqlite3GlobalConfig.m.xFree(p);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    sqlite3GlobalConfig.m.xFree(p);
+  }
+}
+
+/*
+** Free memory that might be associated with a particular database
+** connection.
+*/
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  if( isLookaside(db, p) ){
+    LookasideSlot *pBuf = (LookasideSlot*)p;
+    pBuf->pNext = db->lookaside.pFree;
+    db->lookaside.pFree = pBuf;
+    db->lookaside.nOut--;
+  }else{
+    sqlite3_free(p);
+  }
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+SQLITE_PRIVATE void *sqlite3Realloc(void *pOld, int nBytes){
+  int nOld, nNew;
+  void *pNew;
+  if( pOld==0 ){
+    return sqlite3Malloc(nBytes);
+  }
+  if( nBytes<=0 ){
+    sqlite3_free(pOld);
+    return 0;
+  }
+  if( nBytes>=0x7fffff00 ){
+    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
+    return 0;
+  }
+  nOld = sqlite3MallocSize(pOld);
+  nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
+  if( nOld==nNew ){
+    pNew = pOld;
+  }else if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
+    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED)+nNew-nOld >= 
+          mem0.alarmThreshold ){
+      sqlite3MallocAlarm(nNew-nOld);
+    }
+    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+    if( pNew==0 && mem0.alarmCallback ){
+      sqlite3MallocAlarm(nBytes);
+      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+    }
+    if( pNew ){
+      nNew = sqlite3MallocSize(pNew);
+      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
+    }
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+  }
+  return pNew;
+}
+
+/*
+** The public interface to sqlite3Realloc.  Make sure that the memory
+** subsystem is initialized prior to invoking sqliteRealloc.
+*/
+SQLITE_API void *sqlite3_realloc(void *pOld, int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  return sqlite3Realloc(pOld, n);
+}
+
 
 /*
 ** Allocate and zero memory.
 */ 
-SQLITE_PRIVATE void *sqlite3MallocZero(unsigned n){
-  void *p = sqlite3_malloc(n);
+SQLITE_PRIVATE void *sqlite3MallocZero(int n){
+  void *p = sqlite3Malloc(n);
   if( p ){
     memset(p, 0, n);
   }
@@ -13847,7 +16175,7 @@ SQLITE_PRIVATE void *sqlite3MallocZero(unsigned n){
 ** Allocate and zero memory.  If the allocation fails, make
 ** the mallocFailed flag in the connection pointer.
 */
-SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, unsigned n){
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, int n){
   void *p = sqlite3DbMallocRaw(db, n);
   if( p ){
     memset(p, 0, n);
@@ -13858,28 +16186,78 @@ SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, unsigned n){
 /*
 ** Allocate and zero memory.  If the allocation fails, make
 ** the mallocFailed flag in the connection pointer.
+**
+** If db!=0 and db->mallocFailed is true (indicating a prior malloc
+** failure on the same database connection) then always return 0.
+** Hence for a particular database connection, once malloc starts
+** failing, it fails consistently until mallocFailed is reset.
+** This is an important assumption.  There are many places in the
+** code that do things like this:
+**
+**         int *a = (int*)sqlite3DbMallocRaw(db, 100);
+**         int *b = (int*)sqlite3DbMallocRaw(db, 200);
+**         if( b ) a[10] = 9;
+**
+** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
+** that all prior mallocs (ex: "a") worked too.
 */
-SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, unsigned n){
-  void *p = 0;
-  if( !db || db->mallocFailed==0 ){
-    p = sqlite3_malloc(n);
-    if( !p && db ){
-      db->mallocFailed = 1;
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
+  void *p;
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+#ifndef SQLITE_OMIT_LOOKASIDE
+  if( db ){
+    LookasideSlot *pBuf;
+    if( db->mallocFailed ){
+      return 0;
     }
+    if( db->lookaside.bEnabled && n<=db->lookaside.sz
+         && (pBuf = db->lookaside.pFree)!=0 ){
+      db->lookaside.pFree = pBuf->pNext;
+      db->lookaside.nOut++;
+      if( db->lookaside.nOut>db->lookaside.mxOut ){
+        db->lookaside.mxOut = db->lookaside.nOut;
+      }
+      return (void*)pBuf;
+    }
+  }
+#else
+  if( db && db->mallocFailed ){
+    return 0;
+  }
+#endif
+  p = sqlite3Malloc(n);
+  if( !p && db ){
+    db->mallocFailed = 1;
   }
   return p;
 }
 
 /*
 ** Resize the block of memory pointed to by p to n bytes. If the
-** resize fails, set the mallocFailed flag inthe connection object.
+** resize fails, set the mallocFailed flag in the connection object.
 */
 SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *db, void *p, int n){
   void *pNew = 0;
+  assert( db!=0 );
+  assert( sqlite3_mutex_held(db->mutex) );
   if( db->mallocFailed==0 ){
-    pNew = sqlite3_realloc(p, n);
-    if( !pNew ){
-      db->mallocFailed = 1;
+    if( p==0 ){
+      return sqlite3DbMallocRaw(db, n);
+    }
+    if( isLookaside(db, p) ){
+      if( n<=db->lookaside.sz ){
+        return p;
+      }
+      pNew = sqlite3DbMallocRaw(db, n);
+      if( pNew ){
+        memcpy(pNew, p, db->lookaside.sz);
+        sqlite3DbFree(db, p);
+      }
+    }else{
+      pNew = sqlite3_realloc(p, n);
+      if( !pNew ){
+        db->mallocFailed = 1;
+      }
     }
   }
   return pNew;
@@ -13893,7 +16271,7 @@ SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
   void *pNew;
   pNew = sqlite3DbRealloc(db, p, n);
   if( !pNew ){
-    sqlite3_free(p);
+    sqlite3DbFree(db, p);
   }
   return pNew;
 }
@@ -13905,75 +16283,48 @@ SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
 ** called via macros that record the current file and line number in the
 ** ThreadData structure.
 */
-SQLITE_PRIVATE char *sqlite3StrDup(const char *z){
-  char *zNew;
-  int n;
-  if( z==0 ) return 0;
-  n = strlen(z)+1;
-  zNew = sqlite3_malloc(n);
-  if( zNew ) memcpy(zNew, z, n);
-  return zNew;
-}
-SQLITE_PRIVATE char *sqlite3StrNDup(const char *z, int n){
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
   char *zNew;
-  if( z==0 ) return 0;
-  zNew = sqlite3_malloc(n+1);
+  size_t n;
+  if( z==0 ){
+    return 0;
+  }
+  n = sqlite3Strlen30(z) + 1;
+  assert( (n&0x7fffffff)==n );
+  zNew = sqlite3DbMallocRaw(db, (int)n);
   if( zNew ){
     memcpy(zNew, z, n);
-    zNew[n] = 0;
-  }
-  return zNew;
-}
-
-SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
-  char *zNew = sqlite3StrDup(z);
-  if( z && !zNew ){
-    db->mallocFailed = 1;
   }
   return zNew;
 }
 SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, int n){
-  char *zNew = sqlite3StrNDup(z, n);
-  if( z && !zNew ){
-    db->mallocFailed = 1;
+  char *zNew;
+  if( z==0 ){
+    return 0;
+  }
+  assert( (n&0x7fffffff)==n );
+  zNew = sqlite3DbMallocRaw(db, n+1);
+  if( zNew ){
+    memcpy(zNew, z, n);
+    zNew[n] = 0;
   }
   return zNew;
 }
 
 /*
-** Create a string from the 2nd and subsequent arguments (up to the
-** first NULL argument), store the string in memory obtained from
-** sqliteMalloc() and make the pointer indicated by the 1st argument
-** point to that string.  The 1st argument must either be NULL or 
-** point to memory obtained from sqliteMalloc().
+** Create a string from the zFromat argument and the va_list that follows.
+** Store the string in memory obtained from sqliteMalloc() and make *pz
+** point to that string.
 */
-SQLITE_PRIVATE void sqlite3SetString(char **pz, ...){
+SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zFormat, ...){
   va_list ap;
-  int nByte;
-  const char *z;
-  char *zResult;
+  char *z;
 
-  assert( pz!=0 );
-  nByte = 1;
-  va_start(ap, pz);
-  while( (z = va_arg(ap, const char*))!=0 ){
-    nByte += strlen(z);
-  }
-  va_end(ap);
-  sqlite3_free(*pz);
-  *pz = zResult = sqlite3_malloc(nByte);
-  if( zResult==0 ){
-    return;
-  }
-  *zResult = 0;
-  va_start(ap, pz);
-  while( (z = va_arg(ap, const char*))!=0 ){
-    int n = strlen(z);
-    memcpy(zResult, z, n);
-    zResult += n;
-  }
-  zResult[0] = 0;
+  va_start(ap, zFormat);
+  z = sqlite3VMPrintf(db, zFormat, ap);
   va_end(ap);
+  sqlite3DbFree(db, *pz);
+  *pz = z;
 }
 
 
@@ -13983,10 +16334,10 @@ SQLITE_PRIVATE void sqlite3SetString(char **pz, ...){
 ** sqlite3_realloc.
 **
 ** The returned value is normally a copy of the second argument to this
-** function. However, if a malloc() failure has occured since the previous
+** function. However, if a malloc() failure has occurred since the previous
 ** invocation SQLITE_NOMEM is returned instead. 
 **
-** If the first argument, db, is not NULL and a malloc() error has occured,
+** If the first argument, db, is not NULL and a malloc() error has occurred,
 ** then the connection error-code (the value returned by sqlite3_errcode())
 ** is set to SQLITE_NOMEM.
 */
@@ -13996,7 +16347,7 @@ SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
   ** is unsafe, as is the call to sqlite3Error().
   */
   assert( !db || sqlite3_mutex_held(db->mutex) );
-  if( db && db->mallocFailed ){
+  if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
     sqlite3Error(db, SQLITE_NOMEM, 0);
     db->mallocFailed = 0;
     rc = SQLITE_NOMEM;
@@ -14013,6 +16364,8 @@ SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
 ** an historical reference.  Most of the "enhancements" have been backed
 ** out so that the functionality is now the same as standard printf().
 **
+** $Id: printf.c,v 1.104 2009/06/03 01:24:54 drh Exp $
+**
 **************************************************************************
 **
 ** The following modules is an enhanced replacement for the "printf" subroutines
@@ -14073,15 +16426,16 @@ SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
 #define etPERCENT     8 /* Percent symbol. %% */
 #define etCHARX       9 /* Characters. %c */
 /* The rest are extensions, not normally found in printf() */
-#define etCHARLIT    10 /* Literal characters.  %' */
-#define etSQLESCAPE  11 /* Strings with '\'' doubled.  %q */
-#define etSQLESCAPE2 12 /* Strings with '\'' doubled and enclosed in '',
+#define etSQLESCAPE  10 /* Strings with '\'' doubled.  %q */
+#define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
                           NULL pointers replaced by SQL NULL.  %Q */
-#define etTOKEN      13 /* a pointer to a Token structure */
-#define etSRCLIST    14 /* a pointer to a SrcList */
-#define etPOINTER    15 /* The %p conversion */
-#define etSQLESCAPE3 16 /* %w -> Strings with '\"' doubled */
-#define etORDINAL    17 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
+#define etTOKEN      12 /* a pointer to a Token structure */
+#define etSRCLIST    13 /* a pointer to a SrcList */
+#define etPOINTER    14 /* The %p conversion */
+#define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
+#define etORDINAL    16 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
+
+#define etINVALID     0 /* Any unrecognized conversion type */
 
 
 /*
@@ -14139,11 +16493,13 @@ static const et_info fmtinfo[] = {
   {  'n',  0, 0, etSIZE,       0,  0 },
   {  '%',  0, 0, etPERCENT,    0,  0 },
   {  'p', 16, 0, etPOINTER,    0,  1 },
+
+/* All the rest have the FLAG_INTERN bit set and are thus for internal
+** use only */
   {  'T',  0, 2, etTOKEN,      0,  0 },
   {  'S',  0, 2, etSRCLIST,    0,  0 },
   {  'r', 10, 3, etORDINAL,    0,  0 },
 };
-#define etNINFO  (sizeof(fmtinfo)/sizeof(fmtinfo[0]))
 
 /*
 ** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
@@ -14163,7 +16519,7 @@ static const et_info fmtinfo[] = {
 ** 16 (the number of significant digits in a 64-bit float) '0' is
 ** always returned.
 */
-static int et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
+static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
   int digit;
   LONGDOUBLE_TYPE d;
   if( (*cnt)++ >= 16 ) return '0';
@@ -14171,7 +16527,7 @@ static int et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
   d = digit;
   digit += '0';
   *val = (*val - d)*10.0;
-  return digit;
+  return (char)digit;
 }
 #endif /* SQLITE_OMIT_FLOATING_POINT */
 
@@ -14180,7 +16536,7 @@ static int et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
 */
 static void appendSpace(StrAccum *pAccum, int N){
   static const char zSpaces[] = "                             ";
-  while( N>=sizeof(zSpaces)-1 ){
+  while( N>=(int)sizeof(zSpaces)-1 ){
     sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
     N -= sizeof(zSpaces)-1;
   }
@@ -14191,11 +16547,14 @@ static void appendSpace(StrAccum *pAccum, int N){
 
 /*
 ** On machines with a small stack size, you can redefine the
-** SQLITE_PRINT_BUF_SIZE to be less than 350.  But beware - for
-** smaller values some %f conversions may go into an infinite loop.
+** SQLITE_PRINT_BUF_SIZE to be less than 350.
 */
 #ifndef SQLITE_PRINT_BUF_SIZE
-# define SQLITE_PRINT_BUF_SIZE 350
+# if defined(SQLITE_SMALL_STACK)
+#   define SQLITE_PRINT_BUF_SIZE 50
+# else
+#   define SQLITE_PRINT_BUF_SIZE 350
+# endif
 #endif
 #define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
 
@@ -14226,7 +16585,7 @@ static void appendSpace(StrAccum *pAccum, int N){
 ** seems to make a big difference in determining how fast this beast
 ** will run.
 */
-static void vxprintf(
+SQLITE_PRIVATE void sqlite3VXPrintf(
   StrAccum *pAccum,                  /* Accumulate results here */
   int useExtended,                   /* Allow extended %-conversions */
   const char *fmt,                   /* Format string */
@@ -14252,8 +16611,7 @@ static void vxprintf(
   const et_info *infop;      /* Pointer to the appropriate info structure */
   char buf[etBUFSIZE];       /* Conversion buffer */
   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
-  etByte errorflag = 0;      /* True if an error is encountered */
-  etByte xtype;              /* Conversion paradigm */
+  etByte xtype = 0;          /* Conversion paradigm */
   char *zExtra;              /* Extra memory used for etTCLESCAPE conversions */
 #ifndef SQLITE_OMIT_FLOATING_POINT
   int  exp, e2;              /* exponent of real numbers */
@@ -14276,7 +16634,6 @@ static void vxprintf(
       if( c==0 ) break;
     }
     if( (c=(*++fmt))==0 ){
-      errorflag = 1;
       sqlite3StrAccumAppend(pAccum, "%", 1);
       break;
     }
@@ -14344,8 +16701,9 @@ static void vxprintf(
       flag_long = flag_longlong = 0;
     }
     /* Fetch the info entry for the field */
-    infop = 0;
-    for(idx=0; idx<etNINFO; idx++){
+    infop = &fmtinfo[0];
+    xtype = etINVALID;
+    for(idx=0; idx<ArraySize(fmtinfo); idx++){
       if( c==fmtinfo[idx].fmttype ){
         infop = &fmtinfo[idx];
         if( useExtended || (infop->flags & FLAG_INTERN)==0 ){
@@ -14357,9 +16715,6 @@ static void vxprintf(
       }
     }
     zExtra = 0;
-    if( infop==0 ){
-      return;
-    }
 
 
     /* Limit the precision to prevent overflowing buf[] during conversion */
@@ -14397,9 +16752,13 @@ static void vxprintf(
       case etRADIX:
         if( infop->flags & FLAG_SIGNED ){
           i64 v;
-          if( flag_longlong )   v = va_arg(ap,i64);
-          else if( flag_long )  v = va_arg(ap,long int);
-          else                  v = va_arg(ap,int);
+          if( flag_longlong ){
+            v = va_arg(ap,i64);
+          }else if( flag_long ){
+            v = va_arg(ap,long int);
+          }else{
+            v = va_arg(ap,int);
+          }
           if( v<0 ){
             longvalue = -v;
             prefix = '-';
@@ -14410,9 +16769,13 @@ static void vxprintf(
             else                       prefix = 0;
           }
         }else{
-          if( flag_longlong )   longvalue = va_arg(ap,u64);
-          else if( flag_long )  longvalue = va_arg(ap,unsigned long int);
-          else                  longvalue = va_arg(ap,unsigned int);
+          if( flag_longlong ){
+            longvalue = va_arg(ap,u64);
+          }else if( flag_long ){
+            longvalue = va_arg(ap,unsigned long int);
+          }else{
+            longvalue = va_arg(ap,unsigned int);
+          }
           prefix = 0;
         }
         if( longvalue==0 ) flag_alternateform = 0;
@@ -14422,7 +16785,7 @@ static void vxprintf(
         bufpt = &buf[etBUFSIZE-1];
         if( xtype==etORDINAL ){
           static const char zOrd[] = "thstndrd";
-          int x = longvalue % 10;
+          int x = (int)(longvalue % 10);
           if( x>=4 || (longvalue/10)%10==1 ){
             x = 0;
           }
@@ -14440,7 +16803,7 @@ static void vxprintf(
             longvalue = longvalue/base;
           }while( longvalue>0 );
         }
-        length = &buf[etBUFSIZE-1]-bufpt;
+        length = (int)(&buf[etBUFSIZE-1]-bufpt);
         for(idx=precision-length; idx>0; idx--){
           *(--bufpt) = '0';                             /* Zero pad */
         }
@@ -14449,11 +16812,9 @@ static void vxprintf(
           const char *pre;
           char x;
           pre = &aPrefix[infop->prefix];
-          if( *bufpt!=pre[0] ){
-            for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
-          }
+          for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
         }
-        length = &buf[etBUFSIZE-1]-bufpt;
+        length = (int)(&buf[etBUFSIZE-1]-bufpt);
         break;
       case etFLOAT:
       case etEXP:
@@ -14481,7 +16842,7 @@ static void vxprintf(
         if( xtype==etFLOAT ) realvalue += rounder;
         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
         exp = 0;
-        if( sqlite3IsNaN(realvalue) ){
+        if( sqlite3IsNaN((double)realvalue) ){
           bufpt = "NaN";
           length = 3;
           break;
@@ -14490,9 +16851,9 @@ static void vxprintf(
           while( realvalue>=1e32 && exp<=350 ){ realvalue *= 1e-32; exp+=32; }
           while( realvalue>=1e8 && exp<=350 ){ realvalue *= 1e-8; exp+=8; }
           while( realvalue>=10.0 && exp<=350 ){ realvalue *= 0.1; exp++; }
-          while( realvalue<1e-8 && exp>=-350 ){ realvalue *= 1e8; exp-=8; }
-          while( realvalue<1.0 && exp>=-350 ){ realvalue *= 10.0; exp--; }
-          if( exp>350 || exp<-350 ){
+          while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
+          while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
+          if( exp>350 ){
             if( prefix=='-' ){
               bufpt = "-Inf";
             }else if( prefix=='+' ){
@@ -14500,7 +16861,7 @@ static void vxprintf(
             }else{
               bufpt = "Inf";
             }
-            length = strlen(bufpt);
+            length = sqlite3Strlen30(bufpt);
             break;
           }
         }
@@ -14531,7 +16892,7 @@ static void vxprintf(
           e2 = exp;
         }
         nsd = 0;
-        flag_dp = (precision>0) | flag_alternateform | flag_altform2;
+        flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
         /* The sign in front of the number */
         if( prefix ){
           *(bufpt++) = prefix;
@@ -14550,7 +16911,8 @@ static void vxprintf(
         }
         /* "0" digits after the decimal point but before the first
         ** significant digit of the number */
-        for(e2++; e2<0 && precision>0; precision--, e2++){
+        for(e2++; e2<0; precision--, e2++){
+          assert( precision>0 );
           *(bufpt++) = '0';
         }
         /* Significant digits after the decimal point */
@@ -14570,7 +16932,7 @@ static void vxprintf(
           }
         }
         /* Add the "eNNN" suffix */
-        if( flag_exp || (xtype==etEXP && exp) ){
+        if( flag_exp || xtype==etEXP ){
           *(bufpt++) = aDigits[infop->charset];
           if( exp<0 ){
             *(bufpt++) = '-'; exp = -exp;
@@ -14578,18 +16940,18 @@ static void vxprintf(
             *(bufpt++) = '+';
           }
           if( exp>=100 ){
-            *(bufpt++) = (exp/100)+'0';                /* 100's digit */
+            *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
             exp %= 100;
           }
-          *(bufpt++) = exp/10+'0';                     /* 10's digit */
-          *(bufpt++) = exp%10+'0';                     /* 1's digit */
+          *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
+          *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
         }
         *bufpt = 0;
 
         /* The converted number is in buf[] and zero terminated. Output it.
         ** Note that the number is in the usual order, not reversed as with
         ** integer conversions. */
-        length = bufpt-buf;
+        length = (int)(bufpt-buf);
         bufpt = buf;
 
         /* Special case:  Add leading zeros if the flag_zeropad flag is
@@ -14615,11 +16977,11 @@ static void vxprintf(
         bufpt = buf;
         length = 1;
         break;
-      case etCHARLIT:
       case etCHARX:
-        c = buf[0] = (xtype==etCHARX ? va_arg(ap,int) : *++fmt);
+        c = va_arg(ap,int);
+        buf[0] = (char)c;
         if( precision>=0 ){
-          for(idx=1; idx<precision; idx++) buf[idx] = c;
+          for(idx=1; idx<precision; idx++) buf[idx] = (char)c;
           length = precision;
         }else{
           length =1;
@@ -14637,14 +16999,15 @@ static void vxprintf(
         if( precision>=0 ){
           for(length=0; length<precision && bufpt[length]; length++){}
         }else{
-          length = strlen(bufpt);
+          length = sqlite3Strlen30(bufpt);
         }
         break;
       case etSQLESCAPE:
       case etSQLESCAPE2:
       case etSQLESCAPE3: {
-        int i, j, n, ch, isnull;
+        int i, j, n, isnull;
         int needQuote;
+        char ch;
         char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
         char *escarg = va_arg(ap,char*);
         isnull = escarg==0;
@@ -14655,8 +17018,11 @@ static void vxprintf(
         needQuote = !isnull && xtype==etSQLESCAPE2;
         n += i + 1 + needQuote*2;
         if( n>etBUFSIZE ){
-          bufpt = zExtra = sqlite3_malloc( n );
-          if( bufpt==0 ) return;
+          bufpt = zExtra = sqlite3Malloc( n );
+          if( bufpt==0 ){
+            pAccum->mallocFailed = 1;
+            return;
+          }
         }else{
           bufpt = buf;
         }
@@ -14675,7 +17041,7 @@ static void vxprintf(
       }
       case etTOKEN: {
         Token *pToken = va_arg(ap, Token*);
-        if( pToken && pToken->z ){
+        if( pToken ){
           sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
         }
         length = width = 0;
@@ -14686,7 +17052,7 @@ static void vxprintf(
         int k = va_arg(ap, int);
         struct SrcList_item *pItem = &pSrc->a[k];
         assert( k>=0 && k<pSrc->nSrc );
-        if( pItem->zDatabase && pItem->zDatabase[0] ){
+        if( pItem->zDatabase ){
           sqlite3StrAccumAppend(pAccum, pItem->zDatabase, -1);
           sqlite3StrAccumAppend(pAccum, ".", 1);
         }
@@ -14694,6 +17060,10 @@ static void vxprintf(
         length = width = 0;
         break;
       }
+      default: {
+        assert( xtype==etINVALID );
+        return;
+      }
     }/* End switch over the format type */
     /*
     ** The text of the conversion is pointed to by "bufpt" and is
@@ -14727,13 +17097,16 @@ static void vxprintf(
 ** Append N bytes of text from z to the StrAccum object.
 */
 SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
+  assert( z!=0 || N==0 );
   if( p->tooBig | p->mallocFailed ){
+    testcase(p->tooBig);
+    testcase(p->mallocFailed);
     return;
   }
   if( N<0 ){
-    N = strlen(z);
+    N = sqlite3Strlen30(z);
   }
-  if( N==0 ){
+  if( N==0 || NEVER(z==0) ){
     return;
   }
   if( p->nChar+N >= p->nAlloc ){
@@ -14745,19 +17118,16 @@ SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
         return;
       }
     }else{
-      i64 szNew = p->nAlloc;
+      i64 szNew = p->nChar;
       szNew += N + 1;
       if( szNew > p->mxAlloc ){
-        p->nAlloc = p->mxAlloc;
-        if( ((i64)p->nChar)+((i64)N) >= p->nAlloc ){
-          sqlite3StrAccumReset(p);
-          p->tooBig = 1;
-          return;
-        }
+        sqlite3StrAccumReset(p);
+        p->tooBig = 1;
+        return;
       }else{
-        p->nAlloc = szNew;
+        p->nAlloc = (int)szNew;
       }
-      zNew = sqlite3_malloc( p->nAlloc );
+      zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
       if( zNew ){
         memcpy(zNew, p->zText, p->nChar);
         sqlite3StrAccumReset(p);
@@ -14782,7 +17152,7 @@ SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
   if( p->zText ){
     p->zText[p->nChar] = 0;
     if( p->useMalloc && p->zText==p->zBase ){
-      p->zText = sqlite3_malloc( p->nChar+1 );
+      p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
       if( p->zText ){
         memcpy(p->zText, p->zBase, p->nChar+1);
       }else{
@@ -14798,16 +17168,17 @@ SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
 */
 SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
   if( p->zText!=p->zBase ){
-    sqlite3_free(p->zText);
-    p->zText = 0;
+    sqlite3DbFree(p->db, p->zText);
   }
+  p->zText = 0;
 }
 
 /*
 ** Initialize a string accumulator
 */
-static void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
   p->zText = p->zBase = zBase;
+  p->db = 0;
   p->nChar = 0;
   p->nAlloc = n;
   p->mxAlloc = mx;
@@ -14824,11 +17195,13 @@ SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list a
   char *z;
   char zBase[SQLITE_PRINT_BUF_SIZE];
   StrAccum acc;
+  assert( db!=0 );
   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
-                      db ? db->aLimit[SQLITE_LIMIT_LENGTH] : SQLITE_MAX_LENGTH);
-  vxprintf(&acc, 1, zFormat, ap);
+                      db->aLimit[SQLITE_LIMIT_LENGTH]);
+  acc.db = db;
+  sqlite3VXPrintf(&acc, 1, zFormat, ap);
   z = sqlite3StrAccumFinish(&acc);
-  if( acc.mallocFailed && db ){
+  if( acc.mallocFailed ){
     db->mallocFailed = 1;
   }
   return z;
@@ -14848,6 +17221,24 @@ SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
 }
 
 /*
+** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
+** the string and before returnning.  This routine is intended to be used
+** to modify an existing string.  For example:
+**
+**       x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
+**
+*/
+SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
+  va_list ap;
+  char *z;
+  va_start(ap, zFormat);
+  z = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  sqlite3DbFree(db, zStr);
+  return z;
+}
+
+/*
 ** Print into memory obtained from sqlite3_malloc().  Omit the internal
 ** %-conversion extensions.
 */
@@ -14855,8 +17246,11 @@ SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
   char *z;
   char zBase[SQLITE_PRINT_BUF_SIZE];
   StrAccum acc;
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
-  vxprintf(&acc, 0, zFormat, ap);
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
   z = sqlite3StrAccumFinish(&acc);
   return z;
 }
@@ -14868,6 +17262,9 @@ SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
 SQLITE_API char *sqlite3_mprintf(const char *zFormat, ...){
   va_list ap;
   char *z;
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
   va_start(ap, zFormat);
   z = sqlite3_vmprintf(zFormat, ap);
   va_end(ap);
@@ -14891,13 +17288,13 @@ SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
   sqlite3StrAccumInit(&acc, zBuf, n, 0);
   acc.useMalloc = 0;
   va_start(ap,zFormat);
-  vxprintf(&acc, 0, zFormat, ap);
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
   va_end(ap);
   z = sqlite3StrAccumFinish(&acc);
   return z;
 }
 
-#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG) || defined(SQLITE_MEMDEBUG)
+#if defined(SQLITE_DEBUG)
 /*
 ** A version of printf() that understands %lld.  Used for debugging.
 ** The printf() built into some versions of windows does not understand %lld
@@ -14910,7 +17307,7 @@ SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
   sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
   acc.useMalloc = 0;
   va_start(ap,zFormat);
-  vxprintf(&acc, 0, zFormat, ap);
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
   va_end(ap);
   sqlite3StrAccumFinish(&acc);
   fprintf(stdout,"%s", zBuf);
@@ -14937,14 +17334,14 @@ SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
 ** Random numbers are used by some of the database backends in order
 ** to generate random integer keys for tables or random filenames.
 **
-** $Id: random.c,v 1.23 2008/03/21 16:45:47 drh Exp $
+** $Id: random.c,v 1.29 2008/12/10 19:26:24 drh Exp $
 */
 
 
 /* All threads share a single random number generator.
 ** This structure is the current state of the generator.
 */
-static struct sqlite3PrngType {
+static SQLITE_WSD struct sqlite3PrngType {
   unsigned char isInit;          /* True if initialized */
   unsigned char i, j;            /* State variables */
   unsigned char s[256];          /* State variables */
@@ -14966,10 +17363,24 @@ static struct sqlite3PrngType {
 ** (Later):  Actually, OP_NewRowid does not depend on a good source of
 ** randomness any more.  But we will leave this code in all the same.
 */
-static int randomByte(void){
+static u8 randomByte(void){
   unsigned char t;
 
 
+  /* The "wsdPrng" macro will resolve to the pseudo-random number generator
+  ** state vector.  If writable static data is unsupported on the target,
+  ** we have to locate the state vector at run-time.  In the more common
+  ** case where writable static data is supported, wsdPrng can refer directly
+  ** to the "sqlite3Prng" state vector declared above.
+  */
+#ifdef SQLITE_OMIT_WSD
+  struct sqlite3PrngType *p = &GLOBAL(struct sqlite3PrngType, sqlite3Prng);
+# define wsdPrng p[0]
+#else
+# define wsdPrng sqlite3Prng
+#endif
+
+
   /* Initialize the state of the random number generator once,
   ** the first time this routine is called.  The seed value does
   ** not need to contain a lot of randomness since we are not
@@ -14979,33 +17390,33 @@ static int randomByte(void){
   ** encryption.  The RC4 algorithm is being used as a PRNG (pseudo-random
   ** number generator) not as an encryption device.
   */
-  if( !sqlite3Prng.isInit ){
+  if( !wsdPrng.isInit ){
     int i;
     char k[256];
-    sqlite3Prng.j = 0;
-    sqlite3Prng.i = 0;
+    wsdPrng.j = 0;
+    wsdPrng.i = 0;
     sqlite3OsRandomness(sqlite3_vfs_find(0), 256, k);
     for(i=0; i<256; i++){
-      sqlite3Prng.s[i] = i;
+      wsdPrng.s[i] = (u8)i;
     }
     for(i=0; i<256; i++){
-      sqlite3Prng.j += sqlite3Prng.s[i] + k[i];
-      t = sqlite3Prng.s[sqlite3Prng.j];
-      sqlite3Prng.s[sqlite3Prng.j] = sqlite3Prng.s[i];
-      sqlite3Prng.s[i] = t;
+      wsdPrng.j += wsdPrng.s[i] + k[i];
+      t = wsdPrng.s[wsdPrng.j];
+      wsdPrng.s[wsdPrng.j] = wsdPrng.s[i];
+      wsdPrng.s[i] = t;
     }
-    sqlite3Prng.isInit = 1;
+    wsdPrng.isInit = 1;
   }
 
   /* Generate and return single random byte
   */
-  sqlite3Prng.i++;
-  t = sqlite3Prng.s[sqlite3Prng.i];
-  sqlite3Prng.j += t;
-  sqlite3Prng.s[sqlite3Prng.i] = sqlite3Prng.s[sqlite3Prng.j];
-  sqlite3Prng.s[sqlite3Prng.j] = t;
-  t += sqlite3Prng.s[sqlite3Prng.i];
-  return sqlite3Prng.s[t];
+  wsdPrng.i++;
+  t = wsdPrng.s[wsdPrng.i];
+  wsdPrng.j += t;
+  wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
+  wsdPrng.s[wsdPrng.j] = t;
+  t += wsdPrng.s[wsdPrng.i];
+  return wsdPrng.s[t];
 }
 
 /*
@@ -15013,10 +17424,9 @@ static int randomByte(void){
 */
 SQLITE_API void sqlite3_randomness(int N, void *pBuf){
   unsigned char *zBuf = pBuf;
-  static sqlite3_mutex *mutex = 0;
-  if( mutex==0 ){
-    mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PRNG);
-  }
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
+#endif
   sqlite3_mutex_enter(mutex);
   while( N-- ){
     *(zBuf++) = randomByte();
@@ -15027,19 +17437,30 @@ SQLITE_API void sqlite3_randomness(int N, void *pBuf){
 #ifndef SQLITE_OMIT_BUILTIN_TEST
 /*
 ** For testing purposes, we sometimes want to preserve the state of
-** PRNG and restore the PRNG to its saved state at a later time.
+** PRNG and restore the PRNG to its saved state at a later time, or
+** to reset the PRNG to its initial state.  These routines accomplish
+** those tasks.
+**
 ** The sqlite3_test_control() interface calls these routines to
 ** control the PRNG.
 */
-static struct sqlite3PrngType sqlite3SavedPrng;
+static SQLITE_WSD struct sqlite3PrngType sqlite3SavedPrng;
 SQLITE_PRIVATE void sqlite3PrngSaveState(void){
-  memcpy(&sqlite3SavedPrng, &sqlite3Prng, sizeof(sqlite3Prng));
+  memcpy(
+    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+    sizeof(sqlite3Prng)
+  );
 }
 SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
-  memcpy(&sqlite3Prng, &sqlite3SavedPrng, sizeof(sqlite3Prng));
+  memcpy(
+    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+    sizeof(sqlite3Prng)
+  );
 }
 SQLITE_PRIVATE void sqlite3PrngResetState(void){
-  sqlite3Prng.isInit = 0;
+  GLOBAL(struct sqlite3PrngType, sqlite3Prng).isInit = 0;
 }
 #endif /* SQLITE_OMIT_BUILTIN_TEST */
 
@@ -15059,7 +17480,7 @@ SQLITE_PRIVATE void sqlite3PrngResetState(void){
 ** This file contains routines used to translate between UTF-8, 
 ** UTF-16, UTF-16BE, and UTF-16LE.
 **
-** $Id: utf.c,v 1.61 2008/03/28 15:44:10 danielk1977 Exp $
+** $Id: utf.c,v 1.73 2009/04/01 18:40:32 drh Exp $
 **
 ** Notes on UTF-8:
 **
@@ -15100,19 +17521,13 @@ SQLITE_PRIVATE void sqlite3PrngResetState(void){
 ** source code file "vdbe.c".  When that file became too big (over
 ** 6000 lines long) it was split up into several smaller files and
 ** this header information was factored out.
+**
+** $Id: vdbeInt.h,v 1.174 2009/06/23 14:15:04 drh Exp $
 */
 #ifndef _VDBEINT_H_
 #define _VDBEINT_H_
 
 /*
-** intToKey() and keyToInt() used to transform the rowid.  But with
-** the latest versions of the design they are no-ops.
-*/
-#define keyToInt(X)   (X)
-#define intToKey(X)   (X)
-
-
-/*
 ** SQL is translated into a sequence of instructions to be
 ** executed by a virtual machine.  Each instruction is an instance
 ** of the following structure.
@@ -15134,55 +17549,88 @@ typedef unsigned char Bool;
 ** Every cursor that the virtual machine has open is represented by an
 ** instance of the following structure.
 **
-** If the Cursor.isTriggerRow flag is set it means that this cursor is
+** If the VdbeCursor.isTriggerRow flag is set it means that this cursor is
 ** really a single row that represents the NEW or OLD pseudo-table of
-** a row trigger.  The data for the row is stored in Cursor.pData and
-** the rowid is in Cursor.iKey.
+** a row trigger.  The data for the row is stored in VdbeCursor.pData and
+** the rowid is in VdbeCursor.iKey.
 */
-struct Cursor {
+struct VdbeCursor {
   BtCursor *pCursor;    /* The cursor structure of the backend */
   int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
   i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
-  i64 nextRowid;        /* Next rowid returned by OP_NewRowid */
   Bool zeroed;          /* True if zeroed out and ready for reuse */
   Bool rowidIsValid;    /* True if lastRowid is valid */
   Bool atFirst;         /* True if pointing to first entry */
   Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
   Bool nullRow;         /* True if pointing to a row with no data */
-  Bool nextRowidValid;  /* True if the nextRowid field is valid */
-  Bool pseudoTable;     /* This is a NEW or OLD pseudo-tables of a trigger */
-  Bool ephemPseudoTable;
   Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
   Bool isTable;         /* True if a table requiring integer keys */
   Bool isIndex;         /* True if an index containing keys only - no data */
-  u8 bogusIncrKey;      /* Something for pIncrKey to point to if pKeyInfo==0 */
   i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
   Btree *pBt;           /* Separate file holding temporary table */
-  int nData;            /* Number of bytes in pData */
-  char *pData;          /* Data for a NEW or OLD pseudo-table */
-  i64 iKey;             /* Key for the NEW or OLD pseudo-table row */
-  u8 *pIncrKey;         /* Pointer to pKeyInfo->incrKey */
+  int pseudoTableReg;   /* Register holding pseudotable content. */
   KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
   int nField;           /* Number of fields in the header */
   i64 seqCount;         /* Sequence counter */
   sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
   const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
 
+  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
+  ** OP_IsUnique opcode on this cursor. */
+  int seekResult;
+
   /* Cached information about the header for the data record that the
-  ** cursor is currently pointing to.  Only valid if cacheValid is true.
+  ** cursor is currently pointing to.  Only valid if cacheStatus matches
+  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
+  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
+  ** the cache is out of date.
+  **
   ** aRow might point to (ephemeral) data for the current row, or it might
   ** be NULL.
   */
-  int cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
+  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
   int payloadSize;      /* Total number of bytes in the record */
   u32 *aType;           /* Type values for all entries in the record */
   u32 *aOffset;         /* Cached offsets to the start of each columns data */
   u8 *aRow;             /* Data for the current row, if all on one page */
 };
-typedef struct Cursor Cursor;
+typedef struct VdbeCursor VdbeCursor;
+
+/*
+** When a sub-program is executed (OP_Program), a structure of this type
+** is allocated to store the current value of the program counter, as
+** well as the current memory cell array and various other frame specific
+** values stored in the Vdbe struct. When the sub-program is finished, 
+** these values are copied back to the Vdbe from the VdbeFrame structure,
+** restoring the state of the VM to as it was before the sub-program
+** began executing.
+**
+** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
+** is the parent of the current frame, or zero if the current frame
+** is the main Vdbe program.
+*/
+typedef struct VdbeFrame VdbeFrame;
+struct VdbeFrame {
+  Vdbe *v;                /* VM this frame belongs to */
+  int pc;                 /* Program Counter */
+  Op *aOp;                /* Program instructions */
+  int nOp;                /* Size of aOp array */
+  Mem *aMem;              /* Array of memory cells */
+  int nMem;               /* Number of entries in aMem */
+  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
+  u16 nCursor;            /* Number of entries in apCsr */
+  void *token;            /* Copy of SubProgram.token */
+  int nChildMem;          /* Number of memory cells for child frame */
+  int nChildCsr;          /* Number of cursors for child frame */
+  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
+  int nChange;            /* Statement changes (Vdbe.nChanges)     */
+  VdbeFrame *pParent;     /* Parent of this frame */
+};
+
+#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
 
 /*
-** A value for Cursor.cacheValid that means the cache is always invalid.
+** A value for VdbeCursor.cacheValid that means the cache is always invalid.
 */
 #define CACHE_STALE 0
 
@@ -15199,8 +17647,11 @@ typedef struct Cursor Cursor;
 */
 struct Mem {
   union {
-    i64 i;              /* Integer value. Or FuncDef* when flags==MEM_Agg */
+    i64 i;              /* Integer value. */
+    int nZero;          /* Used when bit MEM_Zero is set in flags */
     FuncDef *pDef;      /* Used only when flags==MEM_Agg */
+    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
+    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
   } u;
   double r;           /* Real value */
   sqlite3 *db;        /* The associated database connection */
@@ -15233,21 +17684,21 @@ struct Mem {
 #define MEM_Int       0x0004   /* Value is an integer */
 #define MEM_Real      0x0008   /* Value is a real number */
 #define MEM_Blob      0x0010   /* Value is a BLOB */
-
-#define MemSetTypeFlag(p, f) \
-  ((p)->flags = ((p)->flags&~(MEM_Int|MEM_Real|MEM_Null|MEM_Blob|MEM_Str))|f)
+#define MEM_RowSet    0x0020   /* Value is a RowSet object */
+#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
+#define MEM_TypeMask  0x00ff   /* Mask of type bits */
 
 /* Whenever Mem contains a valid string or blob representation, one of
 ** the following flags must be set to determine the memory management
 ** policy for Mem.z.  The MEM_Term flag tells us whether or not the
 ** string is \000 or \u0000 terminated
 */
-#define MEM_Term      0x0020   /* String rep is nul terminated */
-#define MEM_Dyn       0x0040   /* Need to call sqliteFree() on Mem.z */
-#define MEM_Static    0x0080   /* Mem.z points to a static string */
-#define MEM_Ephem     0x0100   /* Mem.z points to an ephemeral string */
-#define MEM_Agg       0x0400   /* Mem.z points to an agg function context */
-#define MEM_Zero      0x0800   /* Mem.i contains count of 0s appended to blob */
+#define MEM_Term      0x0200   /* String rep is nul terminated */
+#define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
+#define MEM_Static    0x0800   /* Mem.z points to a static string */
+#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
+#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
+#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
 
 #ifdef SQLITE_OMIT_INCRBLOB
   #undef MEM_Zero
@@ -15255,6 +17706,13 @@ struct Mem {
 #endif
 
 
+/*
+** Clear any existing type flags from a Mem and replace them with f
+*/
+#define MemSetTypeFlag(p, f) \
+   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
+
+
 /* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
 ** additional information about auxiliary information bound to arguments
 ** of the function.  This is used to implement the sqlite3_get_auxdata()
@@ -15308,48 +17766,6 @@ struct Set {
 };
 
 /*
-** A FifoPage structure holds a single page of valves.  Pages are arranged
-** in a list.
-*/
-typedef struct FifoPage FifoPage;
-struct FifoPage {
-  int nSlot;         /* Number of entries aSlot[] */
-  int iWrite;        /* Push the next value into this entry in aSlot[] */
-  int iRead;         /* Read the next value from this entry in aSlot[] */
-  FifoPage *pNext;   /* Next page in the fifo */
-  i64 aSlot[1];      /* One or more slots for rowid values */
-};
-
-/*
-** The Fifo structure is typedef-ed in vdbeInt.h.  But the implementation
-** of that structure is private to this file.
-**
-** The Fifo structure describes the entire fifo.  
-*/
-typedef struct Fifo Fifo;
-struct Fifo {
-  int nEntry;         /* Total number of entries */
-  FifoPage *pFirst;   /* First page on the list */
-  FifoPage *pLast;    /* Last page on the list */
-};
-
-/*
-** A Context stores the last insert rowid, the last statement change count,
-** and the current statement change count (i.e. changes since last statement).
-** The current keylist is also stored in the context.
-** Elements of Context structure type make up the ContextStack, which is
-** updated by the ContextPush and ContextPop opcodes (used by triggers).
-** The context is pushed before executing a trigger a popped when the
-** trigger finishes.
-*/
-typedef struct Context Context;
-struct Context {
-  i64 lastRowid;    /* Last insert rowid (sqlite3.lastRowid) */
-  int nChange;      /* Statement changes (Vdbe.nChanges)     */
-  Fifo sFifo;       /* Records that will participate in a DELETE or UPDATE */
-};
-
-/*
 ** An instance of the virtual machine.  This structure contains the complete
 ** state of the virtual machine.
 **
@@ -15365,88 +17781,55 @@ struct Context {
 ** method function.
 */
 struct Vdbe {
-  sqlite3 *db;        /* The whole database */
-  Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
-  int nOp;            /* Number of instructions in the program */
-  int nOpAlloc;       /* Number of slots allocated for aOp[] */
-  Op *aOp;            /* Space to hold the virtual machine's program */
-  int nLabel;         /* Number of labels used */
-  int nLabelAlloc;    /* Number of slots allocated in aLabel[] */
-  int *aLabel;        /* Space to hold the labels */
-  Mem **apArg;        /* Arguments to currently executing user function */
-  Mem *aColName;      /* Column names to return */
-  int nCursor;        /* Number of slots in apCsr[] */
-  Cursor **apCsr;     /* One element of this array for each open cursor */
-  int nVar;           /* Number of entries in aVar[] */
-  Mem *aVar;          /* Values for the OP_Variable opcode. */
-  char **azVar;       /* Name of variables */
-  int okVar;          /* True if azVar[] has been initialized */
-  int magic;              /* Magic number for sanity checking */
+  sqlite3 *db;            /* The database connection that owns this statement */
+  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
+  int nOp;                /* Number of instructions in the program */
+  int nOpAlloc;           /* Number of slots allocated for aOp[] */
+  Op *aOp;                /* Space to hold the virtual machine's program */
+  int nLabel;             /* Number of labels used */
+  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
+  int *aLabel;            /* Space to hold the labels */
+  Mem **apArg;            /* Arguments to currently executing user function */
+  Mem *aColName;          /* Column names to return */
+  Mem *pResultSet;        /* Pointer to an array of results */
+  u16 nResColumn;         /* Number of columns in one row of the result set */
+  u16 nCursor;            /* Number of slots in apCsr[] */
+  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
+  u8 errorAction;         /* Recovery action to do in case of an error */
+  u8 okVar;               /* True if azVar[] has been initialized */
+  u16 nVar;               /* Number of entries in aVar[] */
+  Mem *aVar;              /* Values for the OP_Variable opcode. */
+  char **azVar;           /* Name of variables */
+  u32 magic;              /* Magic number for sanity checking */
   int nMem;               /* Number of memory locations currently allocated */
   Mem *aMem;              /* The memory locations */
-  int nCallback;          /* Number of callbacks invoked so far */
-  int cacheCtr;           /* Cursor row cache generation counter */
-  Fifo sFifo;             /* A list of ROWIDs */
-  int contextStackTop;    /* Index of top element in the context stack */
-  int contextStackDepth;  /* The size of the "context" stack */
-  Context *contextStack;  /* Stack used by opcodes ContextPush & ContextPop*/
+  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
   int pc;                 /* The program counter */
   int rc;                 /* Value to return */
-  unsigned uniqueCnt;     /* Used by OP_MakeRecord when P2!=0 */
-  int errorAction;        /* Recovery action to do in case of an error */
-  int inTempTrans;        /* True if temp database is transactioned */
-  int returnStack[25];    /* Return address stack for OP_Gosub & OP_Return */
-  int returnDepth;        /* Next unused element in returnStack[] */
-  int nResColumn;         /* Number of columns in one row of the result set */
-  char **azResColumn;     /* Values for one row of result */ 
   char *zErrMsg;          /* Error message written here */
-  Mem *pResultSet;        /* Pointer to an array of results */
   u8 explain;             /* True if EXPLAIN present on SQL command */
   u8 changeCntOn;         /* True to update the change-counter */
-  u8 aborted;             /* True if ROLLBACK in another VM causes an abort */
   u8 expired;             /* True if the VM needs to be recompiled */
   u8 minWriteFileFormat;  /* Minimum file format for writable database files */
   u8 inVtabMethod;        /* See comments above */
+  u8 usesStmtJournal;     /* True if uses a statement journal */
+  u8 readOnly;            /* True for read-only statements */
+  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
   int nChange;            /* Number of db changes made since last reset */
-  i64 startTime;          /* Time when query started - used for profiling */
   int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
+  i64 startTime;          /* Time when query started - used for profiling */
   BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
-  int nSql;             /* Number of bytes in zSql */
-  char *zSql;           /* Text of the SQL statement that generated this */
+  int aCounter[2];        /* Counters used by sqlite3_stmt_status() */
+  char *zSql;             /* Text of the SQL statement that generated this */
+  void *pFree;            /* Free this when deleting the vdbe */
+  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
+  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
+  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
 #ifdef SQLITE_DEBUG
-  FILE *trace;        /* Write an execution trace here, if not NULL */
+  FILE *trace;            /* Write an execution trace here, if not NULL */
 #endif
-  int openedStatement;  /* True if this VM has opened a statement journal */
-#ifdef SQLITE_SSE
-  int fetchId;          /* Statement number used by sqlite3_fetch_statement */
-  int lru;              /* Counter used for LRU cache replacement */
-#endif
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  Vdbe *pLruPrev;
-  Vdbe *pLruNext;
-#endif
-};
-
-/*
-** An instance of the following structure holds information about a
-** single index record that has already been parsed out into individual
-** values.
-**
-** A record is an object that contains one or more fields of data.
-** Records are used to store the content of a table row and to store
-** the key of an index.  A blob encoding of a record is created by
-** the OP_MakeRecord opcode of the VDBE and is disassemblied by the
-** OP_Column opcode.
-**
-** This structure holds a record that has already been disassembled
-** into its constitutent fields.
-*/
-struct UnpackedRecord {
-  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
-  u16 nField;         /* Number of entries in apMem[] */
-  u8 needFree;        /* True if memory obtained from sqlite3_malloc() */
-  u8 needDestroy;     /* True if apMem[]s should be destroyed on close */
-  Mem *aMem;          /* Values */
+  VdbeFrame *pFrame;      /* Parent frame */
+  int nFrame;             /* Number of frames in pFrame list */
 };
 
 /*
@@ -15460,23 +17843,22 @@ struct UnpackedRecord {
 /*
 ** Function prototypes
 */
-SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, Cursor*);
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
 void sqliteVdbePopStack(Vdbe*,int);
-SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(Cursor*);
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
 SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
 #endif
-SQLITE_PRIVATE int sqlite3VdbeSerialTypeLen(u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
 SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
-SQLITE_PRIVATE int sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
-SQLITE_PRIVATE int sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
 SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
 
 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
-SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(Cursor*,UnpackedRecord *,int,const unsigned char*,int*);
-SQLITE_PRIVATE int sqlite3VdbeIdxRowid(BtCursor *, i64 *);
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
 SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
-SQLITE_PRIVATE int sqlite3VdbeIdxRowidLen(const u8*);
 SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
 SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
 SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
@@ -15491,8 +17873,8 @@ SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
 SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem*, double);
 SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
 SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
+SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
 SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemDynamicify(Mem*);
 SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
 SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
 SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
@@ -15507,23 +17889,31 @@ SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
 SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
 SQLITE_PRIVATE int sqlite3VdbeOpcodeHasProperty(int, int);
 SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
 SQLITE_PRIVATE int sqlite3VdbeReleaseBuffers(Vdbe *p);
 #endif
 
-#ifndef NDEBUG
-SQLITE_PRIVATE   void sqlite3VdbeMemSanity(Mem*);
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
+#else
+# define sqlite3VdbeCheckFk(p,i) 0
+#endif
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
+#else
+# define sqlite3VdbeMutexArrayEnter(p)
 #endif
+
 SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE   void sqlite3VdbePrintSql(Vdbe*);
 SQLITE_PRIVATE   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
 #endif
 SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
-SQLITE_PRIVATE void sqlite3VdbeFifoInit(Fifo*);
-SQLITE_PRIVATE int sqlite3VdbeFifoPush(Fifo*, i64);
-SQLITE_PRIVATE int sqlite3VdbeFifoPop(Fifo*, i64*);
-SQLITE_PRIVATE void sqlite3VdbeFifoClear(Fifo*);
 
 #ifndef SQLITE_OMIT_INCRBLOB
 SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
@@ -15536,17 +17926,19 @@ SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
 /************** End of vdbeInt.h *********************************************/
 /************** Continuing where we left off in utf.c ************************/
 
+#ifndef SQLITE_AMALGAMATION
 /*
 ** The following constant value is used by the SQLITE_BIGENDIAN and
 ** SQLITE_LITTLEENDIAN macros.
 */
 SQLITE_PRIVATE const int sqlite3one = 1;
+#endif /* SQLITE_AMALGAMATION */
 
 /*
 ** This lookup table is used to help decode the first byte of
 ** a multi-byte UTF8 character.
 */
-static const unsigned char sqlite3UtfTrans1[] = {
+static const unsigned char sqlite3Utf8Trans1[] = {
   0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
   0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
   0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
@@ -15560,67 +17952,65 @@ static const unsigned char sqlite3UtfTrans1[] = {
 
 #define WRITE_UTF8(zOut, c) {                          \
   if( c<0x00080 ){                                     \
-    *zOut++ = (c&0xFF);                                \
+    *zOut++ = (u8)(c&0xFF);                            \
   }                                                    \
   else if( c<0x00800 ){                                \
-    *zOut++ = 0xC0 + ((c>>6)&0x1F);                    \
-    *zOut++ = 0x80 + (c & 0x3F);                       \
+    *zOut++ = 0xC0 + (u8)((c>>6)&0x1F);                \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
   }                                                    \
   else if( c<0x10000 ){                                \
-    *zOut++ = 0xE0 + ((c>>12)&0x0F);                   \
-    *zOut++ = 0x80 + ((c>>6) & 0x3F);                  \
-    *zOut++ = 0x80 + (c & 0x3F);                       \
+    *zOut++ = 0xE0 + (u8)((c>>12)&0x0F);               \
+    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
   }else{                                               \
-    *zOut++ = 0xF0 + ((c>>18) & 0x07);                 \
-    *zOut++ = 0x80 + ((c>>12) & 0x3F);                 \
-    *zOut++ = 0x80 + ((c>>6) & 0x3F);                  \
-    *zOut++ = 0x80 + (c & 0x3F);                       \
+    *zOut++ = 0xF0 + (u8)((c>>18) & 0x07);             \
+    *zOut++ = 0x80 + (u8)((c>>12) & 0x3F);             \
+    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
   }                                                    \
 }
 
-#define WRITE_UTF16LE(zOut, c) {                                \
-  if( c<=0xFFFF ){                                              \
-    *zOut++ = (c&0x00FF);                                       \
-    *zOut++ = ((c>>8)&0x00FF);                                  \
-  }else{                                                        \
-    *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
-    *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03));              \
-    *zOut++ = (c&0x00FF);                                       \
-    *zOut++ = (0x00DC + ((c>>8)&0x03));                         \
-  }                                                             \
+#define WRITE_UTF16LE(zOut, c) {                                    \
+  if( c<=0xFFFF ){                                                  \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
+  }else{                                                            \
+    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
+    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
+  }                                                                 \
 }
 
-#define WRITE_UTF16BE(zOut, c) {                                \
-  if( c<=0xFFFF ){                                              \
-    *zOut++ = ((c>>8)&0x00FF);                                  \
-    *zOut++ = (c&0x00FF);                                       \
-  }else{                                                        \
-    *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03));              \
-    *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
-    *zOut++ = (0x00DC + ((c>>8)&0x03));                         \
-    *zOut++ = (c&0x00FF);                                       \
-  }                                                             \
+#define WRITE_UTF16BE(zOut, c) {                                    \
+  if( c<=0xFFFF ){                                                  \
+    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+  }else{                                                            \
+    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
+    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
+    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+  }                                                                 \
 }
 
 #define READ_UTF16LE(zIn, c){                                         \
   c = (*zIn++);                                                       \
   c += ((*zIn++)<<8);                                                 \
-  if( c>=0xD800 && c<0xE000 ){                                       \
+  if( c>=0xD800 && c<0xE000 ){                                        \
     int c2 = (*zIn++);                                                \
     c2 += ((*zIn++)<<8);                                              \
     c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
-    if( (c & 0xFFFF0000)==0 ) c = 0xFFFD;                             \
   }                                                                   \
 }
 
 #define READ_UTF16BE(zIn, c){                                         \
   c = ((*zIn++)<<8);                                                  \
   c += (*zIn++);                                                      \
-  if( c>=0xD800 && c<0xE000 ){                                       \
+  if( c>=0xD800 && c<0xE000 ){                                        \
     int c2 = ((*zIn++)<<8);                                           \
     c2 += (*zIn++);                                                   \
     c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
-    if( (c & 0xFFFF0000)==0 ) c = 0xFFFD;                             \
   }                                                                   \
 }
 
@@ -15651,27 +18041,43 @@ static const unsigned char sqlite3UtfTrans1[] = {
 **     for unicode values 0x80 and greater.  It do not change over-length
 **     encodings to 0xfffd as some systems recommend.
 */
+#define READ_UTF8(zIn, zTerm, c)                           \
+  c = *(zIn++);                                            \
+  if( c>=0xc0 ){                                           \
+    c = sqlite3Utf8Trans1[c-0xc0];                         \
+    while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){            \
+      c = (c<<6) + (0x3f & *(zIn++));                      \
+    }                                                      \
+    if( c<0x80                                             \
+        || (c&0xFFFFF800)==0xD800                          \
+        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }        \
+  }
 SQLITE_PRIVATE int sqlite3Utf8Read(
-  const unsigned char *z,         /* First byte of UTF-8 character */
-  const unsigned char *zTerm,     /* Pretend this byte is 0x00 */
+  const unsigned char *zIn,       /* First byte of UTF-8 character */
   const unsigned char **pzNext    /* Write first byte past UTF-8 char here */
 ){
-  int c = *(z++);
+  int c;
+
+  /* Same as READ_UTF8() above but without the zTerm parameter.
+  ** For this routine, we assume the UTF8 string is always zero-terminated.
+  */
+  c = *(zIn++);
   if( c>=0xc0 ){
-    c = sqlite3UtfTrans1[c-0xc0];
-    while( z!=zTerm && (*z & 0xc0)==0x80 ){
-      c = (c<<6) + (0x3f & *(z++));
+    c = sqlite3Utf8Trans1[c-0xc0];
+    while( (*zIn & 0xc0)==0x80 ){
+      c = (c<<6) + (0x3f & *(zIn++));
     }
     if( c<0x80
         || (c&0xFFFFF800)==0xD800
         || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }
   }
-  *pzNext = z;
+  *pzNext = zIn;
   return c;
 }
 
 
 
+
 /*
 ** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
 ** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
@@ -15719,7 +18125,7 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
       return SQLITE_NOMEM;
     }
     zIn = (u8*)pMem->z;
-    zTerm = &zIn[pMem->n];
+    zTerm = &zIn[pMem->n&~1];
     while( zIn<zTerm ){
       temp = *zIn;
       *zIn = *(zIn+1);
@@ -15737,6 +18143,7 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
     ** A single byte is required for the output string
     ** nul-terminator.
     */
+    pMem->n &= ~1;
     len = pMem->n * 2 + 1;
   }else{
     /* When converting from UTF-8 to UTF-16 the maximum growth is caused
@@ -15765,18 +18172,20 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
     if( desiredEnc==SQLITE_UTF16LE ){
       /* UTF-8 -> UTF-16 Little-endian */
       while( zIn<zTerm ){
-        c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
+        /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */
+        READ_UTF8(zIn, zTerm, c);
         WRITE_UTF16LE(z, c);
       }
     }else{
       assert( desiredEnc==SQLITE_UTF16BE );
       /* UTF-8 -> UTF-16 Big-endian */
       while( zIn<zTerm ){
-        c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
+        /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */
+        READ_UTF8(zIn, zTerm, c);
         WRITE_UTF16BE(z, c);
       }
     }
-    pMem->n = z - zOut;
+    pMem->n = (int)(z - zOut);
     *z++ = 0;
   }else{
     assert( desiredEnc==SQLITE_UTF8 );
@@ -15787,13 +18196,13 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
         WRITE_UTF8(z, c);
       }
     }else{
-      /* UTF-16 Little-endian -> UTF-8 */
+      /* UTF-16 Big-endian -> UTF-8 */
       while( zIn<zTerm ){
         READ_UTF16BE(zIn, c); 
         WRITE_UTF8(z, c);
       }
     }
-    pMem->n = z - zOut;
+    pMem->n = (int)(z - zOut);
   }
   *z = 0;
   assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
@@ -15829,7 +18238,8 @@ SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem){
   int rc = SQLITE_OK;
   u8 bom = 0;
 
-  if( pMem->n<0 || pMem->n>1 ){
+  assert( pMem->n>=0 );
+  if( pMem->n>1 ){
     u8 b1 = *(u8 *)pMem->z;
     u8 b2 = *(((u8 *)pMem->z) + 1);
     if( b1==0xFE && b2==0xFF ){
@@ -15895,17 +18305,16 @@ SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *zIn, int nByte){
 SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char *zIn){
   unsigned char *zOut = zIn;
   unsigned char *zStart = zIn;
-  unsigned char *zTerm;
   u32 c;
 
   while( zIn[0] ){
-    c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
+    c = sqlite3Utf8Read(zIn, (const u8**)&zIn);
     if( c!=0xfffd ){
       WRITE_UTF8(zOut, c);
     }
   }
   *zOut = 0;
-  return zOut - zStart;
+  return (int)(zOut - zStart);
 }
 #endif
 
@@ -15933,15 +18342,39 @@ SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte){
 }
 
 /*
-** pZ is a UTF-16 encoded unicode string. If nChar is less than zero,
-** return the number of bytes up to (but not including), the first pair
-** of consecutive 0x00 bytes in pZ. If nChar is not less than zero,
-** then return the number of bytes in the first nChar unicode characters
-** in pZ (or up until the first pair of 0x00 bytes, whichever comes first).
+** Convert a UTF-8 string to the UTF-16 encoding specified by parameter
+** enc. A pointer to the new string is returned, and the value of *pnOut
+** is set to the length of the returned string in bytes. The call should
+** arrange to call sqlite3DbFree() on the returned pointer when it is
+** no longer required.
+** 
+** If a malloc failure occurs, NULL is returned and the db.mallocFailed
+** flag set.
+*/
+#ifdef SQLITE_ENABLE_STAT2
+SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *db, u8 enc, char *z, int n, int *pnOut){
+  Mem m;
+  memset(&m, 0, sizeof(m));
+  m.db = db;
+  sqlite3VdbeMemSetStr(&m, z, n, SQLITE_UTF8, SQLITE_STATIC);
+  if( sqlite3VdbeMemTranslate(&m, enc) ){
+    assert( db->mallocFailed );
+    return 0;
+  }
+  assert( m.z==m.zMalloc );
+  *pnOut = m.n;
+  return m.z;
+}
+#endif
+
+/*
+** pZ is a UTF-16 encoded unicode string at least nChar characters long.
+** Return the number of bytes in the first nChar unicode characters
+** in pZ.  nChar must be non-negative.
 */
 SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
-  unsigned int c = 1;
-  char const *z = zIn;
+  int c;
+  unsigned char const *z = zIn;
   int n = 0;
   if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
     /* Using an "if (SQLITE_UTF16NATIVE==SQLITE_UTF16BE)" construct here
@@ -15953,17 +18386,17 @@ SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
     ** which branch will be followed. It is therefore assumed that no runtime
     ** penalty is paid for this "if" statement.
     */
-    while( c && ((nChar<0) || n<nChar) ){
+    while( n<nChar ){
       READ_UTF16BE(z, c);
       n++;
     }
   }else{
-    while( c && ((nChar<0) || n<nChar) ){
+    while( n<nChar ){
       READ_UTF16LE(z, c);
       n++;
     }
   }
-  return (z-(char const *)zIn)-((c==0)?2:0);
+  return (int)(z-(unsigned char const *)zIn);
 }
 
 #if defined(SQLITE_TEST)
@@ -15972,22 +18405,21 @@ SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
 ** It checks that the primitives for serializing and deserializing
 ** characters in each encoding are inverses of each other.
 */
-SQLITE_PRIVATE void sqlite3UtfSelfTest(){
+SQLITE_PRIVATE void sqlite3UtfSelfTest(void){
   unsigned int i, t;
   unsigned char zBuf[20];
   unsigned char *z;
-  unsigned char *zTerm;
   int n;
   unsigned int c;
 
   for(i=0; i<0x00110000; i++){
     z = zBuf;
     WRITE_UTF8(z, i);
-    n = z-zBuf;
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
     z[0] = 0;
-    zTerm = z;
     z = zBuf;
-    c = sqlite3Utf8Read(z, zTerm, (const u8**)&z);
+    c = sqlite3Utf8Read(z, (const u8**)&z);
     t = i;
     if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
     if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
@@ -15998,7 +18430,8 @@ SQLITE_PRIVATE void sqlite3UtfSelfTest(){
     if( i>=0xD800 && i<0xE000 ) continue;
     z = zBuf;
     WRITE_UTF16LE(z, i);
-    n = z-zBuf;
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
     z[0] = 0;
     z = zBuf;
     READ_UTF16LE(z, c);
@@ -16009,7 +18442,8 @@ SQLITE_PRIVATE void sqlite3UtfSelfTest(){
     if( i>=0xD800 && i<0xE000 ) continue;
     z = zBuf;
     WRITE_UTF16BE(z, i);
-    n = z-zBuf;
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
     z[0] = 0;
     z = zBuf;
     READ_UTF16BE(z, c);
@@ -16038,15 +18472,37 @@ SQLITE_PRIVATE void sqlite3UtfSelfTest(){
 ** This file contains functions for allocating memory, comparing
 ** strings, and stuff like that.
 **
-** $Id: util.c,v 1.229 2008/05/13 16:41:50 drh Exp $
 */
+#ifdef SQLITE_HAVE_ISNAN
+# include <math.h>
+#endif
 
+/*
+** Routine needed to support the testcase() macro.
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int x){
+  static int dummy = 0;
+  dummy += x;
+}
+#endif
 
 /*
-** Return true if the floating point value is Not a Number.
+** Return true if the floating point value is Not a Number (NaN).
+**
+** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
+** Otherwise, we have our own implementation that works on most systems.
 */
 SQLITE_PRIVATE int sqlite3IsNaN(double x){
-  /* This NaN test sometimes fails if compiled on GCC with -ffast-math.
+  int rc;   /* The value return */
+#if !defined(SQLITE_HAVE_ISNAN)
+  /*
+  ** Systems that support the isnan() library function should probably
+  ** make use of it by compiling with -DSQLITE_HAVE_ISNAN.  But we have
+  ** found that many systems do not have a working isnan() function so
+  ** this implementation is provided as an alternative.
+  **
+  ** This NaN test sometimes fails if compiled on GCC with -ffast-math.
   ** On the other hand, the use of -ffast-math comes with the following
   ** warning:
   **
@@ -16054,9 +18510,41 @@ SQLITE_PRIVATE int sqlite3IsNaN(double x){
   **      -O option since it can result in incorrect output for programs
   **      which depend on an exact implementation of IEEE or ISO 
   **      rules/specifications for math functions.
+  **
+  ** Under MSVC, this NaN test may fail if compiled with a floating-
+  ** point precision mode other than /fp:precise.  From the MSDN 
+  ** documentation:
+  **
+  **      The compiler [with /fp:precise] will properly handle comparisons 
+  **      involving NaN. For example, x != x evaluates to true if x is NaN 
+  **      ...
   */
+#ifdef __FAST_MATH__
+# error SQLite will not work correctly with the -ffast-math option of GCC.
+#endif
   volatile double y = x;
-  return x!=y;
+  volatile double z = y;
+  rc = (y!=z);
+#else  /* if defined(SQLITE_HAVE_ISNAN) */
+  rc = isnan(x);
+#endif /* SQLITE_HAVE_ISNAN */
+  testcase( rc );
+  return rc;
+}
+
+/*
+** Compute a string length that is limited to what can be stored in
+** lower 30 bits of a 32-bit signed integer.
+**
+** The value returned will never be negative.  Nor will it ever be greater
+** than the actual length of the string.  For very long strings (greater
+** than 1GiB) the value returned might be less than the true string length.
+*/
+SQLITE_PRIVATE int sqlite3Strlen30(const char *z){
+  const char *z2 = z;
+  if( z==0 ) return 0;
+  while( *z2 ){ z2++; }
+  return 0x3fffffff & (int)(z2 - z);
 }
 
 /*
@@ -16089,7 +18577,7 @@ SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat,
       va_start(ap, zFormat);
       z = sqlite3VMPrintf(db, zFormat, ap);
       va_end(ap);
-      sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, sqlite3_free);
+      sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
     }else{
       sqlite3ValueSetStr(db->pErr, 0, 0, SQLITE_UTF8, SQLITE_STATIC);
     }
@@ -16115,21 +18603,20 @@ SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat,
 */
 SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
   va_list ap;
+  sqlite3 *db = pParse->db;
   pParse->nErr++;
-  sqlite3_free(pParse->zErrMsg);
+  sqlite3DbFree(db, pParse->zErrMsg);
   va_start(ap, zFormat);
-  pParse->zErrMsg = sqlite3VMPrintf(pParse->db, zFormat, ap);
+  pParse->zErrMsg = sqlite3VMPrintf(db, zFormat, ap);
   va_end(ap);
-  if( pParse->rc==SQLITE_OK ){
-    pParse->rc = SQLITE_ERROR;
-  }
+  pParse->rc = SQLITE_ERROR;
 }
 
 /*
 ** Clear the error message in pParse, if any
 */
 SQLITE_PRIVATE void sqlite3ErrorClear(Parse *pParse){
-  sqlite3_free(pParse->zErrMsg);
+  sqlite3DbFree(pParse->db, pParse->zErrMsg);
   pParse->zErrMsg = 0;
   pParse->nErr = 0;
 }
@@ -16140,77 +18627,46 @@ SQLITE_PRIVATE void sqlite3ErrorClear(Parse *pParse){
 ** input does not begin with a quote character, then this routine
 ** is a no-op.
 **
+** The input string must be zero-terminated.  A new zero-terminator
+** is added to the dequoted string.
+**
+** The return value is -1 if no dequoting occurs or the length of the
+** dequoted string, exclusive of the zero terminator, if dequoting does
+** occur.
+**
 ** 2002-Feb-14: This routine is extended to remove MS-Access style
 ** brackets from around identifers.  For example:  "[a-b-c]" becomes
 ** "a-b-c".
 */
-SQLITE_PRIVATE void sqlite3Dequote(char *z){
-  int quote;
+SQLITE_PRIVATE int sqlite3Dequote(char *z){
+  char quote;
   int i, j;
-  if( z==0 ) return;
+  if( z==0 ) return -1;
   quote = z[0];
   switch( quote ){
     case '\'':  break;
     case '"':   break;
     case '`':   break;                /* For MySQL compatibility */
     case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
-    default:    return;
+    default:    return -1;
   }
-  for(i=1, j=0; z[i]; i++){
+  for(i=1, j=0; ALWAYS(z[i]); i++){
     if( z[i]==quote ){
       if( z[i+1]==quote ){
         z[j++] = quote;
         i++;
       }else{
-        z[j++] = 0;
         break;
       }
     }else{
       z[j++] = z[i];
     }
   }
+  z[j] = 0;
+  return j;
 }
 
-/* An array to map all upper-case characters into their corresponding
-** lower-case character. 
-*/
-SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[] = {
-#ifdef SQLITE_ASCII
-      0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17,
-     18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
-     36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
-     54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
-    104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
-    122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
-    108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
-    126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
-    144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
-    162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
-    180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
-    198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
-    216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
-    234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
-    252,253,254,255
-#endif
-#ifdef SQLITE_EBCDIC
-      0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, /* 0x */
-     16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, /* 1x */
-     32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, /* 2x */
-     48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, /* 3x */
-     64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, /* 4x */
-     80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, /* 5x */
-     96, 97, 66, 67, 68, 69, 70, 71, 72, 73,106,107,108,109,110,111, /* 6x */
-    112, 81, 82, 83, 84, 85, 86, 87, 88, 89,122,123,124,125,126,127, /* 7x */
-    128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143, /* 8x */
-    144,145,146,147,148,149,150,151,152,153,154,155,156,157,156,159, /* 9x */
-    160,161,162,163,164,165,166,167,168,169,170,171,140,141,142,175, /* Ax */
-    176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191, /* Bx */
-    192,129,130,131,132,133,134,135,136,137,202,203,204,205,206,207, /* Cx */
-    208,145,146,147,148,149,150,151,152,153,218,219,220,221,222,223, /* Dx */
-    224,225,162,163,164,165,166,167,168,169,232,203,204,205,206,207, /* Ex */
-    239,240,241,242,243,244,245,246,247,248,249,219,220,221,222,255, /* Fx */
-#endif
-};
+/* Convenient short-hand */
 #define UpperToLower sqlite3UpperToLower
 
 /*
@@ -16224,7 +18680,7 @@ SQLITE_PRIVATE int sqlite3StrICmp(const char *zLeft, const char *zRight){
   while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
   return UpperToLower[*a] - UpperToLower[*b];
 }
-SQLITE_PRIVATE int sqlite3StrNICmp(const char *zLeft, const char *zRight, int N){
+SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
   register unsigned char *a, *b;
   a = (unsigned char *)zLeft;
   b = (unsigned char *)zRight;
@@ -16233,10 +18689,15 @@ SQLITE_PRIVATE int sqlite3StrNICmp(const char *zLeft, const char *zRight, int N)
 }
 
 /*
-** Return TRUE if z is a pure numeric string.  Return FALSE if the
-** string contains any character which is not part of a number. If
-** the string is numeric and contains the '.' character, set *realnum
-** to TRUE (otherwise FALSE).
+** Return TRUE if z is a pure numeric string.  Return FALSE and leave
+** *realnum unchanged if the string contains any character which is not
+** part of a number.
+**
+** If the string is pure numeric, set *realnum to TRUE if the string
+** contains the '.' character or an "E+000" style exponentiation suffix.
+** Otherwise set *realnum to FALSE.  Note that just becaue *realnum is
+** false does not mean that the number can be successfully converted into
+** an integer - it might be too big.
 **
 ** An empty string is considered non-numeric.
 */
@@ -16244,30 +18705,30 @@ SQLITE_PRIVATE int sqlite3IsNumber(const char *z, int *realnum, u8 enc){
   int incr = (enc==SQLITE_UTF8?1:2);
   if( enc==SQLITE_UTF16BE ) z++;
   if( *z=='-' || *z=='+' ) z += incr;
-  if( !isdigit(*(u8*)z) ){
+  if( !sqlite3Isdigit(*z) ){
     return 0;
   }
   z += incr;
-  if( realnum ) *realnum = 0;
-  while( isdigit(*(u8*)z) ){ z += incr; }
+  *realnum = 0;
+  while( sqlite3Isdigit(*z) ){ z += incr; }
   if( *z=='.' ){
     z += incr;
-    if( !isdigit(*(u8*)z) ) return 0;
-    while( isdigit(*(u8*)z) ){ z += incr; }
-    if( realnum ) *realnum = 1;
+    if( !sqlite3Isdigit(*z) ) return 0;
+    while( sqlite3Isdigit(*z) ){ z += incr; }
+    *realnum = 1;
   }
   if( *z=='e' || *z=='E' ){
     z += incr;
     if( *z=='+' || *z=='-' ) z += incr;
-    if( !isdigit(*(u8*)z) ) return 0;
-    while( isdigit(*(u8*)z) ){ z += incr; }
-    if( realnum ) *realnum = 1;
+    if( !sqlite3Isdigit(*z) ) return 0;
+    while( sqlite3Isdigit(*z) ){ z += incr; }
+    *realnum = 1;
   }
   return *z==0;
 }
 
 /*
-** The string z[] is an ascii representation of a real number.
+** The string z[] is an ASCII representation of a real number.
 ** Convert this string to a double.
 **
 ** This routine assumes that z[] really is a valid number.  If it
@@ -16280,71 +18741,127 @@ SQLITE_PRIVATE int sqlite3IsNumber(const char *z, int *realnum, u8 enc){
 */
 SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult){
 #ifndef SQLITE_OMIT_FLOATING_POINT
-  int sign = 1;
   const char *zBegin = z;
-  LONGDOUBLE_TYPE v1 = 0.0;
-  int nSignificant = 0;
-  while( isspace(*(u8*)z) ) z++;
+  /* sign * significand * (10 ^ (esign * exponent)) */
+  int sign = 1;   /* sign of significand */
+  i64 s = 0;      /* significand */
+  int d = 0;      /* adjust exponent for shifting decimal point */
+  int esign = 1;  /* sign of exponent */
+  int e = 0;      /* exponent */
+  double result;
+  int nDigits = 0;
+
+  /* skip leading spaces */
+  while( sqlite3Isspace(*z) ) z++;
+  /* get sign of significand */
   if( *z=='-' ){
     sign = -1;
     z++;
   }else if( *z=='+' ){
     z++;
   }
-  while( z[0]=='0' ){
-    z++;
-  }
-  while( isdigit(*(u8*)z) ){
-    v1 = v1*10.0 + (*z - '0');
-    z++;
-    nSignificant++;
+  /* skip leading zeroes */
+  while( z[0]=='0' ) z++, nDigits++;
+
+  /* copy max significant digits to significand */
+  while( sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
+    s = s*10 + (*z - '0');
+    z++, nDigits++;
   }
+  /* skip non-significant significand digits
+  ** (increase exponent by d to shift decimal left) */
+  while( sqlite3Isdigit(*z) ) z++, nDigits++, d++;
+
+  /* if decimal point is present */
   if( *z=='.' ){
-    LONGDOUBLE_TYPE divisor = 1.0;
     z++;
-    if( nSignificant==0 ){
-      while( z[0]=='0' ){
-        divisor *= 10.0;
-        z++;
-      }
+    /* copy digits from after decimal to significand
+    ** (decrease exponent by d to shift decimal right) */
+    while( sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
+      s = s*10 + (*z - '0');
+      z++, nDigits++, d--;
     }
-    while( isdigit(*(u8*)z) ){
-      if( nSignificant<18 ){
-        v1 = v1*10.0 + (*z - '0');
-        divisor *= 10.0;
-        nSignificant++;
-      }
-      z++;
-    }
-    v1 /= divisor;
+    /* skip non-significant digits */
+    while( sqlite3Isdigit(*z) ) z++, nDigits++;
   }
+
+  /* if exponent is present */
   if( *z=='e' || *z=='E' ){
-    int esign = 1;
-    int eval = 0;
-    LONGDOUBLE_TYPE scale = 1.0;
     z++;
+    /* get sign of exponent */
     if( *z=='-' ){
       esign = -1;
       z++;
     }else if( *z=='+' ){
       z++;
     }
-    while( isdigit(*(u8*)z) ){
-      eval = eval*10 + *z - '0';
+    /* copy digits to exponent */
+    while( sqlite3Isdigit(*z) ){
+      e = e*10 + (*z - '0');
       z++;
     }
-    while( eval>=64 ){ scale *= 1.0e+64; eval -= 64; }
-    while( eval>=16 ){ scale *= 1.0e+16; eval -= 16; }
-    while( eval>=4 ){ scale *= 1.0e+4; eval -= 4; }
-    while( eval>=1 ){ scale *= 1.0e+1; eval -= 1; }
-    if( esign<0 ){
-      v1 /= scale;
+  }
+
+  /* adjust exponent by d, and update sign */
+  e = (e*esign) + d;
+  if( e<0 ) {
+    esign = -1;
+    e *= -1;
+  } else {
+    esign = 1;
+  }
+
+  /* if 0 significand */
+  if( !s ) {
+    /* In the IEEE 754 standard, zero is signed.
+    ** Add the sign if we've seen at least one digit */
+    result = (sign<0 && nDigits) ? -(double)0 : (double)0;
+  } else {
+    /* attempt to reduce exponent */
+    if( esign>0 ){
+      while( s<(LARGEST_INT64/10) && e>0 ) e--,s*=10;
     }else{
-      v1 *= scale;
+      while( !(s%10) && e>0 ) e--,s/=10;
+    }
+
+    /* adjust the sign of significand */
+    s = sign<0 ? -s : s;
+
+    /* if exponent, scale significand as appropriate
+    ** and store in result. */
+    if( e ){
+      double scale = 1.0;
+      /* attempt to handle extremely small/large numbers better */
+      if( e>307 && e<342 ){
+        while( e%308 ) { scale *= 1.0e+1; e -= 1; }
+        if( esign<0 ){
+          result = s / scale;
+          result /= 1.0e+308;
+        }else{
+          result = s * scale;
+          result *= 1.0e+308;
+        }
+      }else{
+        /* 1.0e+22 is the largest power of 10 than can be 
+        ** represented exactly. */
+        while( e%22 ) { scale *= 1.0e+1; e -= 1; }
+        while( e>0 ) { scale *= 1.0e+22; e -= 22; }
+        if( esign<0 ){
+          result = s / scale;
+        }else{
+          result = s * scale;
+        }
+      }
+    } else {
+      result = (double)s;
     }
   }
-  *pResult = sign<0 ? -v1 : v1;
-  return z - zBegin;
+
+  /* store the result */
+  *pResult = result;
+
+  /* return number of characters used */
+  return (int)(z - zBegin);
 #else
   return sqlite3Atoi64(z, pResult);
 #endif /* SQLITE_OMIT_FLOATING_POINT */
@@ -16365,7 +18882,7 @@ SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult){
 */
 static int compare2pow63(const char *zNum){
   int c;
-  c = memcmp(zNum,"922337203685477580",18);
+  c = memcmp(zNum,"922337203685477580",18)*10;
   if( c==0 ){
     c = zNum[18] - '8';
   }
@@ -16387,7 +18904,8 @@ SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum){
   i64 v = 0;
   int neg;
   int i, c;
-  while( isspace(*(u8*)zNum) ) zNum++;
+  const char *zStart;
+  while( sqlite3Isspace(*zNum) ) zNum++;
   if( *zNum=='-' ){
     neg = 1;
     zNum++;
@@ -16397,12 +18915,13 @@ SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum){
   }else{
     neg = 0;
   }
+  zStart = zNum;
   while( zNum[0]=='0' ){ zNum++; } /* Skip over leading zeros. Ticket #2454 */
   for(i=0; (c=zNum[i])>='0' && c<='9'; i++){
     v = v*10 + c - '0';
   }
   *pNum = neg ? -v : v;
-  if( c!=0 || i==0 || i>19 ){
+  if( c!=0 || (i==0 && zStart==zNum) || i>19 ){
     /* zNum is empty or contains non-numeric text or is longer
     ** than 19 digits (thus guaranting that it is too large) */
     return 0;
@@ -16418,30 +18937,33 @@ SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum){
 }
 
 /*
-** The string zNum represents an integer.  There might be some other
-** information following the integer too, but that part is ignored.
-** If the integer that the prefix of zNum represents will fit in a
+** The string zNum represents an unsigned integer.  The zNum string
+** consists of one or more digit characters and is terminated by
+** a zero character.  Any stray characters in zNum result in undefined
+** behavior.
+**
+** If the unsigned integer that zNum represents will fit in a
 ** 64-bit signed integer, return TRUE.  Otherwise return FALSE.
 **
-** This routine returns FALSE for the string -9223372036854775808 even that
-** that number will, in theory fit in a 64-bit integer.  Positive
-** 9223373036854775808 will not fit in 64 bits.  So it seems safer to return
-** false.
+** If the negFlag parameter is true, that means that zNum really represents
+** a negative number.  (The leading "-" is omitted from zNum.)  This
+** parameter is needed to determine a boundary case.  A string
+** of "9223373036854775808" returns false if negFlag is false or true
+** if negFlag is true.
+**
+** Leading zeros are ignored.
 */
 SQLITE_PRIVATE int sqlite3FitsIn64Bits(const char *zNum, int negFlag){
-  int i, c;
+  int i;
   int neg = 0;
-  if( *zNum=='-' ){
-    neg = 1;
-    zNum++;
-  }else if( *zNum=='+' ){
-    zNum++;
-  }
+
+  assert( zNum[0]>='0' && zNum[0]<='9' ); /* zNum is an unsigned number */
+
   if( negFlag ) neg = 1-neg;
   while( *zNum=='0' ){
     zNum++;   /* Skip leading zeros.  Ticket #2454 */
   }
-  for(i=0; (c=zNum[i])>='0' && c<='9'; i++){}
+  for(i=0; zNum[i]; i++){ assert( zNum[i]>='0' && zNum[i]<='9' ); }
   if( i<19 ){
     /* Guaranteed to fit if less than 19 digits */
     return 1;
@@ -16528,17 +19050,17 @@ SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
   int i, j, n;
   u8 buf[10];
   if( v & (((u64)0xff000000)<<32) ){
-    p[8] = v;
+    p[8] = (u8)v;
     v >>= 8;
     for(i=7; i>=0; i--){
-      p[i] = (v & 0x7f) | 0x80;
+      p[i] = (u8)((v & 0x7f) | 0x80);
       v >>= 7;
     }
     return 9;
   }    
   n = 0;
   do{
-    buf[n++] = (v & 0x7f) | 0x80;
+    buf[n++] = (u8)((v & 0x7f) | 0x80);
     v >>= 7;
   }while( v!=0 );
   buf[0] &= 0x7f;
@@ -16565,8 +19087,8 @@ SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char *p, u32 v){
   }
 #endif
   if( (v & ~0x3fff)==0 ){
-    p[0] = (v>>7) | 0x80;
-    p[1] = v & 0x7f;
+    p[0] = (u8)((v>>7) | 0x80);
+    p[1] = (u8)(v & 0x7f);
     return 2;
   }
   return sqlite3PutVarint(p, v);
@@ -16576,11 +19098,11 @@ SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char *p, u32 v){
 ** Read a 64-bit variable-length integer from memory starting at p[0].
 ** Return the number of bytes read.  The value is stored in *v.
 */
-SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
   u32 a,b,s;
 
   a = *p;
-  /* a: p0 (unmasked)*/
+  /* a: p0 (unmasked) */
   if (!(a&0x80))
   {
     *v = a;
@@ -16589,7 +19111,7 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
 
   p++;
   b = *p;
-  /* b: p1 (unmasked)*/
+  /* b: p1 (unmasked) */
   if (!(b&0x80))
   {
     a &= 0x7f;
@@ -16602,7 +19124,7 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
   p++;
   a = a<<14;
   a |= *p;
-  /* a: p0<<14 | p2 (unmasked)*/
+  /* a: p0<<14 | p2 (unmasked) */
   if (!(a&0x80))
   {
     a &= (0x7f<<14)|(0x7f);
@@ -16613,41 +19135,41 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
     return 3;
   }
 
-  /* CSE1 from below*/
+  /* CSE1 from below */
   a &= (0x7f<<14)|(0x7f);
   p++;
   b = b<<14;
   b |= *p;
-  /* b: p1<<14 | p3 (unmasked)*/
+  /* b: p1<<14 | p3 (unmasked) */
   if (!(b&0x80))
   {
     b &= (0x7f<<14)|(0x7f);
-    /* moved CSE1 up*/
-    /* a &= (0x7f<<14)|(0x7f);*/
+    /* moved CSE1 up */
+    /* a &= (0x7f<<14)|(0x7f); */
     a = a<<7;
     a |= b;
     *v = a;
     return 4;
   }
 
-  /* a: p0<<14 | p2 (masked)*/
-  /* b: p1<<14 | p3 (unmasked)*/
-  /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked)*/
-  /* moved CSE1 up*/
-  /* a &= (0x7f<<14)|(0x7f);*/
+  /* a: p0<<14 | p2 (masked) */
+  /* b: p1<<14 | p3 (unmasked) */
+  /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+  /* moved CSE1 up */
+  /* a &= (0x7f<<14)|(0x7f); */
   b &= (0x7f<<14)|(0x7f);
   s = a;
-  /* s: p0<<14 | p2 (masked)*/
+  /* s: p0<<14 | p2 (masked) */
 
   p++;
   a = a<<14;
   a |= *p;
-  /* a: p0<<28 | p2<<14 | p4 (unmasked)*/
+  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
   if (!(a&0x80))
   {
-    /* we can skip these cause they were (effectively) done above in calc'ing s*/
-    /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f);*/
-    /* b &= (0x7f<<14)|(0x7f);*/
+    /* we can skip these cause they were (effectively) done above in calc'ing s */
+    /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+    /* b &= (0x7f<<14)|(0x7f); */
     b = b<<7;
     a |= b;
     s = s>>18;
@@ -16655,19 +19177,19 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
     return 5;
   }
 
-  /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked)*/
+  /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
   s = s<<7;
   s |= b;
-  /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked)*/
+  /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
 
   p++;
   b = b<<14;
   b |= *p;
-  /* b: p1<<28 | p3<<14 | p5 (unmasked)*/
+  /* b: p1<<28 | p3<<14 | p5 (unmasked) */
   if (!(b&0x80))
   {
-    /* we can skip this cause it was (effectively) done above in calc'ing s*/
-    /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f);*/
+    /* we can skip this cause it was (effectively) done above in calc'ing s */
+    /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
     a &= (0x7f<<14)|(0x7f);
     a = a<<7;
     a |= b;
@@ -16679,10 +19201,10 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
   p++;
   a = a<<14;
   a |= *p;
-  /* a: p2<<28 | p4<<14 | p6 (unmasked)*/
+  /* a: p2<<28 | p4<<14 | p6 (unmasked) */
   if (!(a&0x80))
   {
-    a &= (0x7f<<28)|(0x7f<<14)|(0x7f);
+    a &= (0x1f<<28)|(0x7f<<14)|(0x7f);
     b &= (0x7f<<14)|(0x7f);
     b = b<<7;
     a |= b;
@@ -16691,17 +19213,17 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
     return 7;
   }
 
-  /* CSE2 from below*/
+  /* CSE2 from below */
   a &= (0x7f<<14)|(0x7f);
   p++;
   b = b<<14;
   b |= *p;
-  /* b: p3<<28 | p5<<14 | p7 (unmasked)*/
+  /* b: p3<<28 | p5<<14 | p7 (unmasked) */
   if (!(b&0x80))
   {
-    b &= (0x7f<<28)|(0x7f<<14)|(0x7f);
-    /* moved CSE2 up*/
-    /* a &= (0x7f<<14)|(0x7f);*/
+    b &= (0x1f<<28)|(0x7f<<14)|(0x7f);
+    /* moved CSE2 up */
+    /* a &= (0x7f<<14)|(0x7f); */
     a = a<<7;
     a |= b;
     s = s>>4;
@@ -16712,10 +19234,10 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
   p++;
   a = a<<15;
   a |= *p;
-  /* a: p4<<29 | p6<<15 | p8 (unmasked)*/
+  /* a: p4<<29 | p6<<15 | p8 (unmasked) */
 
-  /* moved CSE2 up*/
-  /* a &= (0x7f<<29)|(0x7f<<15)|(0xff);*/
+  /* moved CSE2 up */
+  /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
   b &= (0x7f<<14)|(0x7f);
   b = b<<8;
   a |= b;
@@ -16734,40 +19256,51 @@ SQLITE_PRIVATE int sqlite3GetVarint(const unsigned char *p, u64 *v){
 /*
 ** Read a 32-bit variable-length integer from memory starting at p[0].
 ** Return the number of bytes read.  The value is stored in *v.
+**
+** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
+** integer, then set *v to 0xffffffff.
+**
 ** A MACRO version, getVarint32, is provided which inlines the 
 ** single-byte case.  All code should use the MACRO version as 
 ** this function assumes the single-byte case has already been handled.
 */
-SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *p, u32 *v){
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
   u32 a,b;
 
+  /* The 1-byte case.  Overwhelmingly the most common.  Handled inline
+  ** by the getVarin32() macro */
   a = *p;
-  /* a: p0 (unmasked)*/
+  /* a: p0 (unmasked) */
 #ifndef getVarint32
   if (!(a&0x80))
   {
+    /* Values between 0 and 127 */
     *v = a;
     return 1;
   }
 #endif
 
+  /* The 2-byte case */
   p++;
   b = *p;
-  /* b: p1 (unmasked)*/
+  /* b: p1 (unmasked) */
   if (!(b&0x80))
   {
+    /* Values between 128 and 16383 */
     a &= 0x7f;
     a = a<<7;
     *v = a | b;
     return 2;
   }
 
+  /* The 3-byte case */
   p++;
   a = a<<14;
   a |= *p;
-  /* a: p0<<14 | p2 (unmasked)*/
+  /* a: p0<<14 | p2 (unmasked) */
   if (!(a&0x80))
   {
+    /* Values between 16384 and 2097151 */
     a &= (0x7f<<14)|(0x7f);
     b &= 0x7f;
     b = b<<7;
@@ -16775,12 +19308,43 @@ SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *p, u32 *v){
     return 3;
   }
 
+  /* A 32-bit varint is used to store size information in btrees.
+  ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
+  ** A 3-byte varint is sufficient, for example, to record the size
+  ** of a 1048569-byte BLOB or string.
+  **
+  ** We only unroll the first 1-, 2-, and 3- byte cases.  The very
+  ** rare larger cases can be handled by the slower 64-bit varint
+  ** routine.
+  */
+#if 1
+  {
+    u64 v64;
+    u8 n;
+
+    p -= 2;
+    n = sqlite3GetVarint(p, &v64);
+    assert( n>3 && n<=9 );
+    if( (v64 & SQLITE_MAX_U32)!=v64 ){
+      *v = 0xffffffff;
+    }else{
+      *v = (u32)v64;
+    }
+    return n;
+  }
+
+#else
+  /* For following code (kept for historical record only) shows an
+  ** unrolling for the 3- and 4-byte varint cases.  This code is
+  ** slightly faster, but it is also larger and much harder to test.
+  */
   p++;
   b = b<<14;
   b |= *p;
-  /* b: p1<<14 | p3 (unmasked)*/
+  /* b: p1<<14 | p3 (unmasked) */
   if (!(b&0x80))
   {
+    /* Values between 2097152 and 268435455 */
     b &= (0x7f<<14)|(0x7f);
     a &= (0x7f<<14)|(0x7f);
     a = a<<7;
@@ -16791,11 +19355,12 @@ SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *p, u32 *v){
   p++;
   a = a<<14;
   a |= *p;
-  /* a: p0<<28 | p2<<14 | p4 (unmasked)*/
+  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
   if (!(a&0x80))
   {
-    a &= (0x7f<<28)|(0x7f<<14)|(0x7f);
-    b &= (0x7f<<28)|(0x7f<<14)|(0x7f);
+    /* Walues  between 268435456 and 34359738367 */
+    a &= (0x1f<<28)|(0x7f<<14)|(0x7f);
+    b &= (0x1f<<28)|(0x7f<<14)|(0x7f);
     b = b<<7;
     *v = a | b;
     return 5;
@@ -16807,7 +19372,7 @@ SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *p, u32 *v){
   ** value. */
   {
     u64 v64;
-    int n;
+    u8 n;
 
     p -= 4;
     n = sqlite3GetVarint(p, &v64);
@@ -16815,6 +19380,7 @@ SQLITE_PRIVATE int sqlite3GetVarint32(const unsigned char *p, u32 *v){
     *v = (u32)v64;
     return n;
   }
+#endif
 }
 
 /*
@@ -16826,7 +19392,7 @@ SQLITE_PRIVATE int sqlite3VarintLen(u64 v){
   do{
     i++;
     v >>= 7;
-  }while( v!=0 && i<9 );
+  }while( v!=0 && ALWAYS(i<9) );
   return i;
 }
 
@@ -16838,10 +19404,10 @@ SQLITE_PRIVATE u32 sqlite3Get4byte(const u8 *p){
   return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
 }
 SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
-  p[0] = v>>24;
-  p[1] = v>>16;
-  p[2] = v>>8;
-  p[3] = v;
+  p[0] = (u8)(v>>24);
+  p[1] = (u8)(v>>16);
+  p[2] = (u8)(v>>8);
+  p[3] = (u8)v;
 }
 
 
@@ -16849,10 +19415,10 @@ SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
 #if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
 /*
 ** Translate a single byte of Hex into an integer.
-** This routinen only works if h really is a valid hexadecimal
+** This routine only works if h really is a valid hexadecimal
 ** character:  0..9a..fA..F
 */
-static int hexToInt(int h){
+static u8 hexToInt(int h){
   assert( (h>='0' && h<='9') ||  (h>='a' && h<='f') ||  (h>='A' && h<='F') );
 #ifdef SQLITE_ASCII
   h += 9*(1&(h>>6));
@@ -16860,7 +19426,7 @@ static int hexToInt(int h){
 #ifdef SQLITE_EBCDIC
   h += 9*(1&~(h>>4));
 #endif
-  return h & 0xf;
+  return (u8)(h & 0xf);
 }
 #endif /* !SQLITE_OMIT_BLOB_LITERAL || SQLITE_HAS_CODEC */
 
@@ -16961,16 +19527,21 @@ SQLITE_PRIVATE int sqlite3SafetyOff(sqlite3 *db){
 ** used as an argument to sqlite3_errmsg() or sqlite3_close().
 */
 SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3 *db){
-  int magic;
+  u32 magic;
   if( db==0 ) return 0;
   magic = db->magic;
-  if( magic!=SQLITE_MAGIC_OPEN &&
-      magic!=SQLITE_MAGIC_BUSY ) return 0;
-  return 1;
+  if( magic!=SQLITE_MAGIC_OPEN 
+#ifdef SQLITE_DEBUG
+     && magic!=SQLITE_MAGIC_BUSY
+#endif
+  ){
+    return 0;
+  }else{
+    return 1;
+  }
 }
 SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
-  int magic;
-  if( db==0 ) return 0;
+  u32 magic;
   magic = db->magic;
   if( magic!=SQLITE_MAGIC_SICK &&
       magic!=SQLITE_MAGIC_OPEN &&
@@ -16994,29 +19565,16 @@ SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
 ** This is the implementation of generic hash-tables
 ** used in SQLite.
 **
-** $Id: hash.c,v 1.28 2008/05/13 13:27:34 drh Exp $
+** $Id: hash.c,v 1.38 2009/05/09 23:29:12 drh Exp $
 */
 
 /* Turn bulk memory into a hash table object by initializing the
 ** fields of the Hash structure.
 **
 ** "pNew" is a pointer to the hash table that is to be initialized.
-** keyClass is one of the constants SQLITE_HASH_INT, SQLITE_HASH_POINTER,
-** SQLITE_HASH_BINARY, or SQLITE_HASH_STRING.  The value of keyClass 
-** determines what kind of key the hash table will use.  "copyKey" is
-** true if the hash table should make its own private copy of keys and
-** false if it should just use the supplied pointer.  CopyKey only makes
-** sense for SQLITE_HASH_STRING and SQLITE_HASH_BINARY and is ignored
-** for other key classes.
 */
-SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew, int keyClass, int copyKey){
+SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew){
   assert( pNew!=0 );
-  assert( keyClass>=SQLITE_HASH_STRING && keyClass<=SQLITE_HASH_BINARY );
-  pNew->keyClass = keyClass;
-#if 0
-  if( keyClass==SQLITE_HASH_POINTER || keyClass==SQLITE_HASH_INT ) copyKey = 0;
-#endif
-  pNew->copyKey = copyKey;
   pNew->first = 0;
   pNew->count = 0;
   pNew->htsize = 0;
@@ -17038,135 +19596,28 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash *pH){
   pH->htsize = 0;
   while( elem ){
     HashElem *next_elem = elem->next;
-    if( pH->copyKey && elem->pKey ){
-      sqlite3_free(elem->pKey);
-    }
     sqlite3_free(elem);
     elem = next_elem;
   }
   pH->count = 0;
 }
 
-#if 0 /* NOT USED */
-/*
-** Hash and comparison functions when the mode is SQLITE_HASH_INT
-*/
-static int intHash(const void *pKey, int nKey){
-  return nKey ^ (nKey<<8) ^ (nKey>>8);
-}
-static int intCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  return n2 - n1;
-}
-#endif
-
-#if 0 /* NOT USED */
-/*
-** Hash and comparison functions when the mode is SQLITE_HASH_POINTER
-*/
-static int ptrHash(const void *pKey, int nKey){
-  uptr x = Addr(pKey);
-  return x ^ (x<<8) ^ (x>>8);
-}
-static int ptrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( pKey1==pKey2 ) return 0;
-  if( pKey1<pKey2 ) return -1;
-  return 1;
-}
-#endif
-
 /*
-** Hash and comparison functions when the mode is SQLITE_HASH_STRING
+** The hashing function.
 */
-static int strHash(const void *pKey, int nKey){
-  const char *z = (const char *)pKey;
+static unsigned int strHash(const char *z, int nKey){
   int h = 0;
-  if( nKey<=0 ) nKey = strlen(z);
+  assert( nKey>=0 );
   while( nKey > 0  ){
     h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
     nKey--;
   }
-  return h & 0x7fffffff;
-}
-static int strCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return sqlite3StrNICmp((const char*)pKey1,(const char*)pKey2,n1);
-}
-
-/*
-** Hash and comparison functions when the mode is SQLITE_HASH_BINARY
-*/
-static int binHash(const void *pKey, int nKey){
-  int h = 0;
-  const char *z = (const char *)pKey;
-  while( nKey-- > 0 ){
-    h = (h<<3) ^ h ^ *(z++);
-  }
-  return h & 0x7fffffff;
-}
-static int binCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return memcmp(pKey1,pKey2,n1);
+  return h;
 }
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** The C syntax in this function definition may be unfamilar to some 
-** programmers, so we provide the following additional explanation:
-**
-** The name of the function is "hashFunction".  The function takes a
-** single parameter "keyClass".  The return value of hashFunction()
-** is a pointer to another function.  Specifically, the return value
-** of hashFunction() is a pointer to a function that takes two parameters
-** with types "const void*" and "int" and returns an "int".
-*/
-static int (*hashFunction(int keyClass))(const void*,int){
-#if 0  /* HASH_INT and HASH_POINTER are never used */
-  switch( keyClass ){
-    case SQLITE_HASH_INT:     return &intHash;
-    case SQLITE_HASH_POINTER: return &ptrHash;
-    case SQLITE_HASH_STRING:  return &strHash;
-    case SQLITE_HASH_BINARY:  return &binHash;;
-    default: break;
-  }
-  return 0;
-#else
-  if( keyClass==SQLITE_HASH_STRING ){
-    return &strHash;
-  }else{
-    assert( keyClass==SQLITE_HASH_BINARY );
-    return &binHash;
-  }
-#endif
-}
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** For help in interpreted the obscure C code in the function definition,
-** see the header comment on the previous function.
-*/
-static int (*compareFunction(int keyClass))(const void*,int,const void*,int){
-#if 0 /* HASH_INT and HASH_POINTER are never used */
-  switch( keyClass ){
-    case SQLITE_HASH_INT:     return &intCompare;
-    case SQLITE_HASH_POINTER: return &ptrCompare;
-    case SQLITE_HASH_STRING:  return &strCompare;
-    case SQLITE_HASH_BINARY:  return &binCompare;
-    default: break;
-  }
-  return 0;
-#else
-  if( keyClass==SQLITE_HASH_STRING ){
-    return &strCompare;
-  }else{
-    assert( keyClass==SQLITE_HASH_BINARY );
-    return &binCompare;
-  }
-#endif
-}
-
-/* Link an element into the hash table
+/* Link pNew element into the hash table pH.  If pEntry!=0 then also
+** insert pNew into the pEntry hash bucket.
 */
 static void insertElement(
   Hash *pH,              /* The complete hash table */
@@ -17174,7 +19625,13 @@ static void insertElement(
   HashElem *pNew         /* The element to be inserted */
 ){
   HashElem *pHead;       /* First element already in pEntry */
-  pHead = pEntry->chain;
+  if( pEntry ){
+    pHead = pEntry->count ? pEntry->chain : 0;
+    pEntry->count++;
+    pEntry->chain = pNew;
+  }else{
+    pHead = 0;
+  }
   if( pHead ){
     pNew->next = pHead;
     pNew->prev = pHead->prev;
@@ -17187,46 +19644,45 @@ static void insertElement(
     pNew->prev = 0;
     pH->first = pNew;
   }
-  pEntry->count++;
-  pEntry->chain = pNew;
 }
 
 
 /* Resize the hash table so that it cantains "new_size" buckets.
-** "new_size" must be a power of 2.  The hash table might fail 
-** to resize if sqlite3_malloc() fails.
+**
+** The hash table might fail to resize if sqlite3_malloc() fails or
+** if the new size is the same as the prior size.
+** Return TRUE if the resize occurs and false if not.
 */
-static void rehash(Hash *pH, int new_size){
+static int rehash(Hash *pH, unsigned int new_size){
   struct _ht *new_ht;            /* The new hash table */
   HashElem *elem, *next_elem;    /* For looping over existing elements */
-  int (*xHash)(const void*,int); /* The hash function */
 
-#ifdef SQLITE_MALLOC_SOFT_LIMIT
+#if SQLITE_MALLOC_SOFT_LIMIT>0
   if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
     new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
   }
-  if( new_size==pH->htsize ) return;
+  if( new_size==pH->htsize ) return 0;
 #endif
 
-  /* There is a call to sqlite3_malloc() inside rehash(). If there is
-  ** already an allocation at pH->ht, then if this malloc() fails it
-  ** is benign (since failing to resize a hash table is a performance
-  ** hit only, not a fatal error).
+  /* The inability to allocates space for a larger hash table is
+  ** a performance hit but it is not a fatal error.  So mark the
+  ** allocation as a benign.
   */
-  if( pH->htsize>0 ) sqlite3FaultBeginBenign(SQLITE_FAULTINJECTOR_MALLOC);
-  new_ht = (struct _ht *)sqlite3MallocZero( new_size*sizeof(struct _ht) );
-  if( pH->htsize>0 ) sqlite3FaultEndBenign(SQLITE_FAULTINJECTOR_MALLOC);
+  sqlite3BeginBenignMalloc();
+  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
+  sqlite3EndBenignMalloc();
 
-  if( new_ht==0 ) return;
+  if( new_ht==0 ) return 0;
   sqlite3_free(pH->ht);
   pH->ht = new_ht;
-  pH->htsize = new_size;
-  xHash = hashFunction(pH->keyClass);
+  pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
+  memset(new_ht, 0, new_size*sizeof(struct _ht));
   for(elem=pH->first, pH->first=0; elem; elem = next_elem){
-    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
+    unsigned int h = strHash(elem->pKey, elem->nKey) % new_size;
     next_elem = elem->next;
     insertElement(pH, &new_ht[h], elem);
   }
+  return 1;
 }
 
 /* This function (for internal use only) locates an element in an
@@ -17235,25 +19691,26 @@ static void rehash(Hash *pH, int new_size){
 */
 static HashElem *findElementGivenHash(
   const Hash *pH,     /* The pH to be searched */
-  const void *pKey,   /* The key we are searching for */
-  int nKey,
-  int h               /* The hash for this key. */
+  const char *pKey,   /* The key we are searching for */
+  int nKey,           /* Bytes in key (not counting zero terminator) */
+  unsigned int h      /* The hash for this key. */
 ){
   HashElem *elem;                /* Used to loop thru the element list */
   int count;                     /* Number of elements left to test */
-  int (*xCompare)(const void*,int,const void*,int);  /* comparison function */
 
   if( pH->ht ){
     struct _ht *pEntry = &pH->ht[h];
     elem = pEntry->chain;
     count = pEntry->count;
-    xCompare = compareFunction(pH->keyClass);
-    while( count-- && elem ){
-      if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
-        return elem;
-      }
-      elem = elem->next;
+  }else{
+    elem = pH->first;
+    count = pH->count;
+  }
+  while( count-- && ALWAYS(elem) ){
+    if( elem->nKey==nKey && sqlite3StrNICmp(elem->pKey,pKey,nKey)==0 ){ 
+      return elem;
     }
+    elem = elem->next;
   }
   return 0;
 }
@@ -17264,7 +19721,7 @@ static HashElem *findElementGivenHash(
 static void removeElementGivenHash(
   Hash *pH,         /* The pH containing "elem" */
   HashElem* elem,   /* The element to be removed from the pH */
-  int h             /* Hash value for the element */
+  unsigned int h    /* Hash value for the element */
 ){
   struct _ht *pEntry;
   if( elem->prev ){
@@ -17275,16 +19732,13 @@ static void removeElementGivenHash(
   if( elem->next ){
     elem->next->prev = elem->prev;
   }
-  pEntry = &pH->ht[h];
-  if( pEntry->chain==elem ){
-    pEntry->chain = elem->next;
-  }
-  pEntry->count--;
-  if( pEntry->count<=0 ){
-    pEntry->chain = 0;
-  }
-  if( pH->copyKey ){
-    sqlite3_free(elem->pKey);
+  if( pH->ht ){
+    pEntry = &pH->ht[h];
+    if( pEntry->chain==elem ){
+      pEntry->chain = elem->next;
+    }
+    pEntry->count--;
+    assert( pEntry->count>=0 );
   }
   sqlite3_free( elem );
   pH->count--;
@@ -17296,30 +19750,22 @@ static void removeElementGivenHash(
 }
 
 /* Attempt to locate an element of the hash table pH with a key
-** that matches pKey,nKey.  Return a pointer to the corresponding 
-** HashElem structure for this element if it is found, or NULL
-** otherwise.
-*/
-SQLITE_PRIVATE HashElem *sqlite3HashFindElem(const Hash *pH, const void *pKey, int nKey){
-  int h;             /* A hash on key */
-  HashElem *elem;    /* The element that matches key */
-  int (*xHash)(const void*,int);  /* The hash function */
-
-  if( pH==0 || pH->ht==0 ) return 0;
-  xHash = hashFunction(pH->keyClass);
-  assert( xHash!=0 );
-  h = (*xHash)(pKey,nKey);
-  elem = findElementGivenHash(pH,pKey,nKey, h % pH->htsize);
-  return elem;
-}
-
-/* Attempt to locate an element of the hash table pH with a key
 ** that matches pKey,nKey.  Return the data for this element if it is
 ** found, or NULL if there is no match.
 */
-SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const void *pKey, int nKey){
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const char *pKey, int nKey){
   HashElem *elem;    /* The element that matches key */
-  elem = sqlite3HashFindElem(pH, pKey, nKey);
+  unsigned int h;    /* A hash on key */
+
+  assert( pH!=0 );
+  assert( pKey!=0 );
+  assert( nKey>=0 );
+  if( pH->ht ){
+    h = strHash(pKey, nKey) % pH->htsize;
+  }else{
+    h = 0;
+  }
+  elem = findElementGivenHash(pH, pKey, nKey, h);
   return elem ? elem->data : 0;
 }
 
@@ -17327,8 +19773,7 @@ SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const void *pKey, int nKey)
 ** and the data is "data".
 **
 ** If no element exists with a matching key, then a new
-** element is created.  A copy of the key is made if the copyKey
-** flag is set.  NULL is returned.
+** element is created and NULL is returned.
 **
 ** If another element already exists with the same key, then the
 ** new data replaces the old data and the old data is returned.
@@ -17338,67 +19783,49 @@ SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const void *pKey, int nKey)
 ** If the "data" parameter to this function is NULL, then the
 ** element corresponding to "key" is removed from the hash table.
 */
-SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const void *pKey, int nKey, void *data){
-  int hraw;             /* Raw hash value of the key */
-  int h;                /* the hash of the key modulo hash table size */
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){
+  unsigned int h;       /* the hash of the key modulo hash table size */
   HashElem *elem;       /* Used to loop thru the element list */
   HashElem *new_elem;   /* New element added to the pH */
-  int (*xHash)(const void*,int);  /* The hash function */
 
   assert( pH!=0 );
-  xHash = hashFunction(pH->keyClass);
-  assert( xHash!=0 );
-  hraw = (*xHash)(pKey, nKey);
+  assert( pKey!=0 );
+  assert( nKey>=0 );
   if( pH->htsize ){
-    h = hraw % pH->htsize;
-    elem = findElementGivenHash(pH,pKey,nKey,h);
-    if( elem ){
-      void *old_data = elem->data;
-      if( data==0 ){
-        removeElementGivenHash(pH,elem,h);
-      }else{
-        elem->data = data;
-        if( !pH->copyKey ){
-          elem->pKey = (void *)pKey;
-        }
-        assert(nKey==elem->nKey);
-      }
-      return old_data;
+    h = strHash(pKey, nKey) % pH->htsize;
+  }else{
+    h = 0;
+  }
+  elem = findElementGivenHash(pH,pKey,nKey,h);
+  if( elem ){
+    void *old_data = elem->data;
+    if( data==0 ){
+      removeElementGivenHash(pH,elem,h);
+    }else{
+      elem->data = data;
+      elem->pKey = pKey;
+      assert(nKey==elem->nKey);
     }
+    return old_data;
   }
   if( data==0 ) return 0;
-  new_elem = (HashElem*)sqlite3_malloc( sizeof(HashElem) );
+  new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
   if( new_elem==0 ) return data;
-  if( pH->copyKey && pKey!=0 ){
-    new_elem->pKey = sqlite3_malloc( nKey );
-    if( new_elem->pKey==0 ){
-      sqlite3_free(new_elem);
-      return data;
-    }
-    memcpy((void*)new_elem->pKey, pKey, nKey);
-  }else{
-    new_elem->pKey = (void*)pKey;
-  }
+  new_elem->pKey = pKey;
   new_elem->nKey = nKey;
+  new_elem->data = data;
   pH->count++;
-  if( pH->htsize==0 ){
-    rehash(pH, 128/sizeof(pH->ht[0]));
-    if( pH->htsize==0 ){
-      pH->count = 0;
-      if( pH->copyKey ){
-        sqlite3_free(new_elem->pKey);
-      }
-      sqlite3_free(new_elem);
-      return data;
+  if( pH->count>=10 && pH->count > 2*pH->htsize ){
+    if( rehash(pH, pH->count*2) ){
+      assert( pH->htsize>0 );
+      h = strHash(pKey, nKey) % pH->htsize;
     }
   }
-  if( pH->count > pH->htsize ){
-    rehash(pH,pH->htsize*2);
+  if( pH->ht ){
+    insertElement(pH, &pH->ht[h], new_elem);
+  }else{
+    insertElement(pH, 0, new_elem);
   }
-  assert( pH->htsize>0 );
-  h = hraw % pH->htsize;
-  insertElement(pH, &pH->ht[h], new_elem);
-  new_elem->data = data;
   return 0;
 }
 
@@ -17413,144 +19840,147 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
      /*   2 */ "Affinity",
      /*   3 */ "Column",
      /*   4 */ "SetCookie",
-     /*   5 */ "Sequence",
-     /*   6 */ "MoveGt",
-     /*   7 */ "RowKey",
-     /*   8 */ "SCopy",
-     /*   9 */ "OpenWrite",
-     /*  10 */ "If",
-     /*  11 */ "VRowid",
+     /*   5 */ "Seek",
+     /*   6 */ "Sequence",
+     /*   7 */ "Savepoint",
+     /*   8 */ "RowKey",
+     /*   9 */ "SCopy",
+     /*  10 */ "OpenWrite",
+     /*  11 */ "If",
      /*  12 */ "CollSeq",
      /*  13 */ "OpenRead",
      /*  14 */ "Expire",
      /*  15 */ "AutoCommit",
-     /*  16 */ "Not",
+     /*  16 */ "Pagecount",
      /*  17 */ "IntegrityCk",
      /*  18 */ "Sort",
-     /*  19 */ "Copy",
-     /*  20 */ "Trace",
-     /*  21 */ "Function",
-     /*  22 */ "IfNeg",
-     /*  23 */ "Noop",
-     /*  24 */ "Return",
-     /*  25 */ "NewRowid",
-     /*  26 */ "Variable",
-     /*  27 */ "String",
-     /*  28 */ "RealAffinity",
-     /*  29 */ "VRename",
-     /*  30 */ "ParseSchema",
-     /*  31 */ "VOpen",
-     /*  32 */ "Close",
-     /*  33 */ "CreateIndex",
-     /*  34 */ "IsUnique",
-     /*  35 */ "NotFound",
-     /*  36 */ "Int64",
-     /*  37 */ "MustBeInt",
-     /*  38 */ "Halt",
-     /*  39 */ "Rowid",
-     /*  40 */ "IdxLT",
-     /*  41 */ "AddImm",
-     /*  42 */ "Statement",
-     /*  43 */ "RowData",
-     /*  44 */ "MemMax",
-     /*  45 */ "NotExists",
-     /*  46 */ "Gosub",
-     /*  47 */ "Integer",
-     /*  48 */ "Prev",
-     /*  49 */ "VColumn",
-     /*  50 */ "CreateTable",
-     /*  51 */ "Last",
-     /*  52 */ "IncrVacuum",
-     /*  53 */ "IdxRowid",
-     /*  54 */ "ResetCount",
-     /*  55 */ "FifoWrite",
-     /*  56 */ "ContextPush",
-     /*  57 */ "DropTrigger",
-     /*  58 */ "DropIndex",
-     /*  59 */ "IdxGE",
-     /*  60 */ "Or",
-     /*  61 */ "And",
-     /*  62 */ "IdxDelete",
-     /*  63 */ "Vacuum",
-     /*  64 */ "MoveLe",
-     /*  65 */ "IsNull",
-     /*  66 */ "NotNull",
-     /*  67 */ "Ne",
-     /*  68 */ "Eq",
-     /*  69 */ "Gt",
-     /*  70 */ "Le",
-     /*  71 */ "Lt",
-     /*  72 */ "Ge",
-     /*  73 */ "IfNot",
-     /*  74 */ "BitAnd",
-     /*  75 */ "BitOr",
-     /*  76 */ "ShiftLeft",
-     /*  77 */ "ShiftRight",
-     /*  78 */ "Add",
-     /*  79 */ "Subtract",
-     /*  80 */ "Multiply",
-     /*  81 */ "Divide",
-     /*  82 */ "Remainder",
-     /*  83 */ "Concat",
-     /*  84 */ "DropTable",
-     /*  85 */ "MakeRecord",
-     /*  86 */ "ResultRow",
-     /*  87 */ "BitNot",
-     /*  88 */ "String8",
-     /*  89 */ "Delete",
-     /*  90 */ "AggFinal",
-     /*  91 */ "Goto",
-     /*  92 */ "TableLock",
-     /*  93 */ "FifoRead",
-     /*  94 */ "Clear",
-     /*  95 */ "MoveLt",
-     /*  96 */ "VerifyCookie",
-     /*  97 */ "AggStep",
-     /*  98 */ "SetNumColumns",
-     /*  99 */ "Transaction",
-     /* 100 */ "VFilter",
-     /* 101 */ "VDestroy",
-     /* 102 */ "ContextPop",
-     /* 103 */ "Next",
-     /* 104 */ "IdxInsert",
-     /* 105 */ "Insert",
-     /* 106 */ "Destroy",
-     /* 107 */ "ReadCookie",
-     /* 108 */ "ForceInt",
-     /* 109 */ "LoadAnalysis",
-     /* 110 */ "Explain",
-     /* 111 */ "OpenPseudo",
-     /* 112 */ "OpenEphemeral",
-     /* 113 */ "Null",
-     /* 114 */ "Move",
-     /* 115 */ "Blob",
-     /* 116 */ "Rewind",
-     /* 117 */ "MoveGe",
-     /* 118 */ "VBegin",
-     /* 119 */ "VUpdate",
-     /* 120 */ "IfZero",
-     /* 121 */ "VCreate",
-     /* 122 */ "Found",
-     /* 123 */ "IfPos",
-     /* 124 */ "NullRow",
-     /* 125 */ "Real",
-     /* 126 */ "NotUsed_126",
-     /* 127 */ "NotUsed_127",
-     /* 128 */ "NotUsed_128",
-     /* 129 */ "NotUsed_129",
-     /* 130 */ "NotUsed_130",
-     /* 131 */ "NotUsed_131",
-     /* 132 */ "NotUsed_132",
-     /* 133 */ "NotUsed_133",
+     /*  19 */ "Not",
+     /*  20 */ "Copy",
+     /*  21 */ "Trace",
+     /*  22 */ "Function",
+     /*  23 */ "IfNeg",
+     /*  24 */ "Noop",
+     /*  25 */ "Program",
+     /*  26 */ "Return",
+     /*  27 */ "NewRowid",
+     /*  28 */ "FkCounter",
+     /*  29 */ "Variable",
+     /*  30 */ "String",
+     /*  31 */ "RealAffinity",
+     /*  32 */ "VRename",
+     /*  33 */ "ParseSchema",
+     /*  34 */ "VOpen",
+     /*  35 */ "Close",
+     /*  36 */ "CreateIndex",
+     /*  37 */ "IsUnique",
+     /*  38 */ "NotFound",
+     /*  39 */ "Int64",
+     /*  40 */ "MustBeInt",
+     /*  41 */ "Halt",
+     /*  42 */ "Rowid",
+     /*  43 */ "IdxLT",
+     /*  44 */ "AddImm",
+     /*  45 */ "RowData",
+     /*  46 */ "MemMax",
+     /*  47 */ "NotExists",
+     /*  48 */ "Gosub",
+     /*  49 */ "Integer",
+     /*  50 */ "Prev",
+     /*  51 */ "RowSetRead",
+     /*  52 */ "RowSetAdd",
+     /*  53 */ "VColumn",
+     /*  54 */ "CreateTable",
+     /*  55 */ "Last",
+     /*  56 */ "SeekLe",
+     /*  57 */ "IncrVacuum",
+     /*  58 */ "IdxRowid",
+     /*  59 */ "ResetCount",
+     /*  60 */ "Yield",
+     /*  61 */ "DropTrigger",
+     /*  62 */ "DropIndex",
+     /*  63 */ "Param",
+     /*  64 */ "IdxGE",
+     /*  65 */ "IdxDelete",
+     /*  66 */ "Vacuum",
+     /*  67 */ "IfNot",
+     /*  68 */ "Or",
+     /*  69 */ "And",
+     /*  70 */ "DropTable",
+     /*  71 */ "SeekLt",
+     /*  72 */ "MakeRecord",
+     /*  73 */ "IsNull",
+     /*  74 */ "NotNull",
+     /*  75 */ "Ne",
+     /*  76 */ "Eq",
+     /*  77 */ "Gt",
+     /*  78 */ "Le",
+     /*  79 */ "Lt",
+     /*  80 */ "Ge",
+     /*  81 */ "ResultRow",
+     /*  82 */ "BitAnd",
+     /*  83 */ "BitOr",
+     /*  84 */ "ShiftLeft",
+     /*  85 */ "ShiftRight",
+     /*  86 */ "Add",
+     /*  87 */ "Subtract",
+     /*  88 */ "Multiply",
+     /*  89 */ "Divide",
+     /*  90 */ "Remainder",
+     /*  91 */ "Concat",
+     /*  92 */ "Delete",
+     /*  93 */ "BitNot",
+     /*  94 */ "String8",
+     /*  95 */ "AggFinal",
+     /*  96 */ "Compare",
+     /*  97 */ "Goto",
+     /*  98 */ "TableLock",
+     /*  99 */ "Clear",
+     /* 100 */ "VerifyCookie",
+     /* 101 */ "AggStep",
+     /* 102 */ "Transaction",
+     /* 103 */ "VFilter",
+     /* 104 */ "VDestroy",
+     /* 105 */ "Next",
+     /* 106 */ "Count",
+     /* 107 */ "IdxInsert",
+     /* 108 */ "FkIfZero",
+     /* 109 */ "SeekGe",
+     /* 110 */ "Insert",
+     /* 111 */ "Destroy",
+     /* 112 */ "ReadCookie",
+     /* 113 */ "RowSetTest",
+     /* 114 */ "LoadAnalysis",
+     /* 115 */ "Explain",
+     /* 116 */ "HaltIfNull",
+     /* 117 */ "OpenPseudo",
+     /* 118 */ "OpenEphemeral",
+     /* 119 */ "Null",
+     /* 120 */ "Move",
+     /* 121 */ "Blob",
+     /* 122 */ "Rewind",
+     /* 123 */ "SeekGt",
+     /* 124 */ "VBegin",
+     /* 125 */ "VUpdate",
+     /* 126 */ "IfZero",
+     /* 127 */ "VCreate",
+     /* 128 */ "Found",
+     /* 129 */ "IfPos",
+     /* 130 */ "Real",
+     /* 131 */ "NullRow",
+     /* 132 */ "Jump",
+     /* 133 */ "Permutation",
      /* 134 */ "NotUsed_134",
      /* 135 */ "NotUsed_135",
      /* 136 */ "NotUsed_136",
      /* 137 */ "NotUsed_137",
-     /* 138 */ "ToText",
-     /* 139 */ "ToBlob",
-     /* 140 */ "ToNumeric",
-     /* 141 */ "ToInt",
-     /* 142 */ "ToReal",
+     /* 138 */ "NotUsed_138",
+     /* 139 */ "NotUsed_139",
+     /* 140 */ "NotUsed_140",
+     /* 141 */ "ToText",
+     /* 142 */ "ToBlob",
+     /* 143 */ "ToNumeric",
+     /* 144 */ "ToInt",
+     /* 145 */ "ToReal",
   };
   return azName[i];
 }
@@ -17571,10 +20001,12 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
 ******************************************************************************
 **
 ** This file contains code that is specific to OS/2.
+**
+** $Id: os_os2.c,v 1.63 2008/12/10 19:26:24 drh Exp $
 */
 
 
-#if OS_OS2
+#if SQLITE_OS_OS2
 
 /*
 ** A Note About Memory Allocation:
@@ -17632,7 +20064,11 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
 **
 ** This file should be #included by the os_*.c files only.  It is not a
 ** general purpose header file.
+**
+** $Id: os_common.h,v 1.38 2009/02/24 18:40:50 danielk1977 Exp $
 */
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
 
 /*
 ** At least two bugs have slipped in because we changed the MEMORY_DEBUG
@@ -17643,15 +20079,6 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
 # error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
 #endif
 
-
-/*
- * When testing, this global variable stores the location of the
- * pending-byte in the database file.
- */
-#ifdef SQLITE_TEST
-SQLITE_API unsigned int sqlite3_pending_byte = 0x40000000;
-#endif
-
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE int sqlite3OSTrace = 0;
 #define OSTRACE1(X)         if( sqlite3OSTrace ) sqlite3DebugPrintf(X)
@@ -17678,22 +20105,113 @@ SQLITE_PRIVATE int sqlite3OSTrace = 0;
 ** on i486 hardware.
 */
 #ifdef SQLITE_PERFORMANCE_TRACE
-__inline__ unsigned long long int hwtime(void){
-  unsigned long long int x;
-  __asm__("rdtsc\n\t"
-          "mov %%edx, %%ecx\n\t"
-          :"=A" (x));
-  return x;
-}
-static unsigned long long int g_start;
-static unsigned int elapse;
-#define TIMER_START       g_start=hwtime()
-#define TIMER_END         elapse=hwtime()-g_start
-#define TIMER_ELAPSED     elapse
+
+/* 
+** hwtime.h contains inline assembler code for implementing 
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+**
+** $Id: hwtime.h,v 1.3 2008/08/01 14:33:15 shane Exp $
+*/
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value.  This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+      (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+  #if defined(__GNUC__)
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+     unsigned int lo, hi;
+     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+     return (sqlite_uint64)hi << 32 | lo;
+  }
+
+  #elif defined(_MSC_VER)
+
+  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+     __asm {
+        rdtsc
+        ret       ; return value at EDX:EAX
+     }
+  }
+
+  #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long val;
+      __asm__ __volatile__ ("rdtsc" : "=A" (val));
+      return val;
+  }
+ 
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long long retval;
+      unsigned long junk;
+      __asm__ __volatile__ ("\n\
+          1:      mftbu   %1\n\
+                  mftb    %L0\n\
+                  mftbu   %0\n\
+                  cmpw    %0,%1\n\
+                  bne     1b"
+                  : "=r" (retval), "=r" (junk));
+      return retval;
+  }
+
+#else
+
+  #error Need implementation of sqlite3Hwtime() for your platform.
+
+  /*
+  ** To compile without implementing sqlite3Hwtime() for your platform,
+  ** you can remove the above #error and use the following
+  ** stub function.  You will lose timing support for many
+  ** of the debugging and testing utilities, but it should at
+  ** least compile and run.
+  */
+SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START       g_start=sqlite3Hwtime()
+#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED     g_elapsed
 #else
 #define TIMER_START
 #define TIMER_END
-#define TIMER_ELAPSED     0
+#define TIMER_ELAPSED     ((sqlite_uint64)0)
 #endif
 
 /*
@@ -17746,6 +20264,8 @@ SQLITE_API int sqlite3_open_file_count = 0;
 #define OpenCounter(X)
 #endif
 
+#endif /* !defined(_OS_COMMON_H_) */
+
 /************** End of os_common.h *******************************************/
 /************** Continuing where we left off in os_os2.c *********************/
 
@@ -17771,7 +20291,7 @@ struct os2File {
 /*
 ** Close a file.
 */
-int os2Close( sqlite3_file *id ){
+static int os2Close( sqlite3_file *id ){
   APIRET rc = NO_ERROR;
   os2File *pFile;
   if( id && (pFile = (os2File*)id) != 0 ){
@@ -17795,7 +20315,7 @@ int os2Close( sqlite3_file *id ){
 ** bytes were read successfully and SQLITE_IOERR if anything goes
 ** wrong.
 */
-int os2Read(
+static int os2Read(
   sqlite3_file *id,               /* File to read from */
   void *pBuf,                     /* Write content into this buffer */
   int amt,                        /* Number of bytes to read */
@@ -17816,6 +20336,7 @@ int os2Read(
   if( got == (ULONG)amt )
     return SQLITE_OK;
   else {
+    /* Unread portions of the input buffer must be zero-filled */
     memset(&((char*)pBuf)[got], 0, amt-got);
     return SQLITE_IOERR_SHORT_READ;
   }
@@ -17825,7 +20346,7 @@ int os2Read(
 ** Write data from a buffer into a file.  Return SQLITE_OK on success
 ** or some other error code on failure.
 */
-int os2Write(
+static int os2Write(
   sqlite3_file *id,               /* File to write into */
   const void *pBuf,               /* The bytes to be written */
   int amt,                        /* Number of bytes to write */
@@ -17857,13 +20378,13 @@ int os2Write(
 /*
 ** Truncate an open file to a specified size
 */
-int os2Truncate( sqlite3_file *id, i64 nByte ){
+static int os2Truncate( sqlite3_file *id, i64 nByte ){
   APIRET rc = NO_ERROR;
   os2File *pFile = (os2File*)id;
   OSTRACE3( "TRUNCATE %d %lld\n", pFile->h, nByte );
   SimulateIOError( return SQLITE_IOERR_TRUNCATE );
   rc = DosSetFileSize( pFile->h, nByte );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
+  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_TRUNCATE;
 }
 
 #ifdef SQLITE_TEST
@@ -17878,7 +20399,7 @@ SQLITE_API int sqlite3_fullsync_count = 0;
 /*
 ** Make sure all writes to a particular file are committed to disk.
 */
-int os2Sync( sqlite3_file *id, int flags ){
+static int os2Sync( sqlite3_file *id, int flags ){
   os2File *pFile = (os2File*)id;
   OSTRACE3( "SYNC %d lock=%d\n", pFile->h, pFile->locktype );
 #ifdef SQLITE_TEST
@@ -17887,24 +20408,32 @@ int os2Sync( sqlite3_file *id, int flags ){
   }
   sqlite3_sync_count++;
 #endif
+  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+  ** no-op
+  */
+#ifdef SQLITE_NO_SYNC
+  UNUSED_PARAMETER(pFile);
+  return SQLITE_OK;
+#else
   return DosResetBuffer( pFile->h ) == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
+#endif
 }
 
 /*
 ** Determine the current size of a file in bytes
 */
-int os2FileSize( sqlite3_file *id, sqlite3_int64 *pSize ){
+static int os2FileSize( sqlite3_file *id, sqlite3_int64 *pSize ){
   APIRET rc = NO_ERROR;
   FILESTATUS3 fsts3FileInfo;
   memset(&fsts3FileInfo, 0, sizeof(fsts3FileInfo));
   assert( id!=0 );
-  SimulateIOError( return SQLITE_IOERR );
+  SimulateIOError( return SQLITE_IOERR_FSTAT );
   rc = DosQueryFileInfo( ((os2File*)id)->h, FIL_STANDARD, &fsts3FileInfo, sizeof(FILESTATUS3) );
   if( rc == NO_ERROR ){
     *pSize = fsts3FileInfo.cbFile;
     return SQLITE_OK;
   }else{
-    return SQLITE_IOERR;
+    return SQLITE_IOERR_FSTAT;
   }
 }
 
@@ -17970,7 +20499,7 @@ static int unlockReadLock( os2File *id ){
 ** It is not possible to lower the locking level one step at a time.  You
 ** must go straight to locking level 0.
 */
-int os2Lock( sqlite3_file *id, int locktype ){
+static int os2Lock( sqlite3_file *id, int locktype ){
   int rc = SQLITE_OK;       /* Return code from subroutines */
   APIRET res = NO_ERROR;    /* Result of an OS/2 lock call */
   int newLocktype;       /* Set pFile->locktype to this value before exiting */
@@ -18106,7 +20635,7 @@ int os2Lock( sqlite3_file *id, int locktype ){
 ** file by this or any other process. If such a lock is held, return
 ** non-zero, otherwise zero.
 */
-int os2CheckReservedLock( sqlite3_file *id ){
+static int os2CheckReservedLock( sqlite3_file *id, int *pOut ){
   int r = 0;
   os2File *pFile = (os2File*)id;
   assert( pFile!=0 );
@@ -18137,7 +20666,8 @@ int os2CheckReservedLock( sqlite3_file *id ){
     r = !(rc == NO_ERROR);
     OSTRACE3( "TEST WR-LOCK %d %d (remote)\n", pFile->h, r );
   }
-  return r;
+  *pOut = r;
+  return SQLITE_OK;
 }
 
 /*
@@ -18151,7 +20681,7 @@ int os2CheckReservedLock( sqlite3_file *id ){
 ** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
 ** might return SQLITE_IOERR;
 */
-int os2Unlock( sqlite3_file *id, int locktype ){
+static int os2Unlock( sqlite3_file *id, int locktype ){
   int type;
   os2File *pFile = (os2File*)id;
   APIRET rc = SQLITE_OK;
@@ -18238,32 +20768,57 @@ static int os2DeviceCharacteristics(sqlite3_file *id){
   return 0;
 }
 
+
+/*
+** Character set conversion objects used by conversion routines.
+*/
+static UconvObject ucUtf8 = NULL; /* convert between UTF-8 and UCS-2 */
+static UconvObject uclCp = NULL;  /* convert between local codepage and UCS-2 */
+
+/*
+** Helper function to initialize the conversion objects from and to UTF-8.
+*/
+static void initUconvObjects( void ){
+  if( UniCreateUconvObject( UTF_8, &ucUtf8 ) != ULS_SUCCESS )
+    ucUtf8 = NULL;
+  if ( UniCreateUconvObject( (UniChar *)L"@path=yes", &uclCp ) != ULS_SUCCESS )
+    uclCp = NULL;
+}
+
+/*
+** Helper function to free the conversion objects from and to UTF-8.
+*/
+static void freeUconvObjects( void ){
+  if ( ucUtf8 )
+    UniFreeUconvObject( ucUtf8 );
+  if ( uclCp )
+    UniFreeUconvObject( uclCp );
+  ucUtf8 = NULL;
+  uclCp = NULL;
+}
+
 /*
 ** Helper function to convert UTF-8 filenames to local OS/2 codepage.
 ** The two-step process: first convert the incoming UTF-8 string
 ** into UCS-2 and then from UCS-2 to the current codepage.
 ** The returned char pointer has to be freed.
 */
-char *convertUtf8PathToCp(const char *in)
-{
-  UconvObject uconv;
-  UniChar ucsUtf8Cp[12],
-          tempPath[CCHMAXPATH];
-  char *out;
-  int rc = 0;
+static char *convertUtf8PathToCp( const char *in ){
+  UniChar tempPath[CCHMAXPATH];
+  char *out = (char *)calloc( CCHMAXPATH, 1 );
+
+  if( !out )
+    return NULL;
 
-  out = (char *)calloc(CCHMAXPATH, 1);
+  if( !ucUtf8 || !uclCp )
+    initUconvObjects();
 
   /* determine string for the conversion of UTF-8 which is CP1208 */
-  rc = UniMapCpToUcsCp(1208, ucsUtf8Cp, 12);
-  rc = UniCreateUconvObject(ucsUtf8Cp, &uconv);
-  rc = UniStrToUcs(uconv, tempPath, (char *)in, CCHMAXPATH);
-  rc = UniFreeUconvObject(uconv);
+  if( UniStrToUcs( ucUtf8, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
+    return out; /* if conversion fails, return the empty string */
 
   /* conversion for current codepage which can be used for paths */
-  rc = UniCreateUconvObject((UniChar *)L"@path=yes", &uconv);
-  rc = UniStrFromUcs(uconv, out, tempPath, CCHMAXPATH);
-  rc = UniFreeUconvObject(uconv);
+  UniStrFromUcs( uclCp, out, tempPath, CCHMAXPATH );
 
   return out;
 }
@@ -18273,27 +20828,26 @@ char *convertUtf8PathToCp(const char *in)
 ** The two-step process: first convert the incoming codepage-specific
 ** string into UCS-2 and then from UCS-2 to the codepage of UTF-8.
 ** The returned char pointer has to be freed.
+**
+** This function is non-static to be able to use this in shell.c and
+** similar applications that take command line arguments.
 */
-char *convertCpPathToUtf8(const char *in)
-{
-  UconvObject uconv;
-  UniChar ucsUtf8Cp[12],
-          tempPath[CCHMAXPATH];
-  char *out;
-  int rc = 0;
+char *convertCpPathToUtf8( const char *in ){
+  UniChar tempPath[CCHMAXPATH];
+  char *out = (char *)calloc( CCHMAXPATH, 1 );
 
-  out = (char *)calloc(CCHMAXPATH, 1);
+  if( !out )
+    return NULL;
+
+  if( !ucUtf8 || !uclCp )
+    initUconvObjects();
 
   /* conversion for current codepage which can be used for paths */
-  rc = UniCreateUconvObject((UniChar *)L"@path=yes", &uconv);
-  rc = UniStrToUcs(uconv, tempPath, (char *)in, CCHMAXPATH);
-  rc = UniFreeUconvObject(uconv);
+  if( UniStrToUcs( uclCp, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
+    return out; /* if conversion fails, return the empty string */
 
   /* determine string for the conversion of UTF-8 which is CP1208 */
-  rc = UniMapCpToUcsCp(1208, ucsUtf8Cp, 12);
-  rc = UniCreateUconvObject(ucsUtf8Cp, &uconv);
-  rc = UniStrFromUcs(uconv, out, tempPath, CCHMAXPATH);
-  rc = UniFreeUconvObject(uconv);
+  UniStrFromUcs( ucUtf8, out, tempPath, CCHMAXPATH );
 
   return out;
 }
@@ -18325,6 +20879,84 @@ static const sqlite3_io_methods os2IoMethod = {
 ****************************************************************************/
 
 /*
+** Create a temporary file name in zBuf.  zBuf must be big enough to
+** hold at pVfs->mxPathname characters.
+*/
+static int getTempname(int nBuf, char *zBuf ){
+  static const unsigned char zChars[] =
+    "abcdefghijklmnopqrstuvwxyz"
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "0123456789";
+  int i, j;
+  char zTempPathBuf[3];
+  PSZ zTempPath = (PSZ)&zTempPathBuf;
+  if( sqlite3_temp_directory ){
+    zTempPath = sqlite3_temp_directory;
+  }else{
+    if( DosScanEnv( (PSZ)"TEMP", &zTempPath ) ){
+      if( DosScanEnv( (PSZ)"TMP", &zTempPath ) ){
+        if( DosScanEnv( (PSZ)"TMPDIR", &zTempPath ) ){
+           ULONG ulDriveNum = 0, ulDriveMap = 0;
+           DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap );
+           sprintf( (char*)zTempPath, "%c:", (char)( 'A' + ulDriveNum - 1 ) );
+        }
+      }
+    }
+  }
+  /* Strip off a trailing slashes or backslashes, otherwise we would get *
+   * multiple (back)slashes which causes DosOpen() to fail.              *
+   * Trailing spaces are not allowed, either.                            */
+  j = sqlite3Strlen30(zTempPath);
+  while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/'
+                    || zTempPath[j-1] == ' ' ) ){
+    j--;
+  }
+  zTempPath[j] = '\0';
+  if( !sqlite3_temp_directory ){
+    char *zTempPathUTF = convertCpPathToUtf8( zTempPath );
+    sqlite3_snprintf( nBuf-30, zBuf,
+                      "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPathUTF );
+    free( zTempPathUTF );
+  }else{
+    sqlite3_snprintf( nBuf-30, zBuf,
+                      "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath );
+  }
+  j = sqlite3Strlen30( zBuf );
+  sqlite3_randomness( 20, &zBuf[j] );
+  for( i = 0; i < 20; i++, j++ ){
+    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+  }
+  zBuf[j] = 0;
+  OSTRACE2( "TEMP FILENAME: %s\n", zBuf );
+  return SQLITE_OK;
+}
+
+
+/*
+** Turn a relative pathname into a full pathname.  Write the full
+** pathname into zFull[].  zFull[] will be at least pVfs->mxPathname
+** bytes in size.
+*/
+static int os2FullPathname(
+  sqlite3_vfs *pVfs,          /* Pointer to vfs object */
+  const char *zRelative,      /* Possibly relative input path */
+  int nFull,                  /* Size of output buffer in bytes */
+  char *zFull                 /* Output buffer */
+){
+  char *zRelativeCp = convertUtf8PathToCp( zRelative );
+  char zFullCp[CCHMAXPATH] = "\0";
+  char *zFullUTF;
+  APIRET rc = DosQueryPathInfo( zRelativeCp, FIL_QUERYFULLNAME, zFullCp,
+                                CCHMAXPATH );
+  free( zRelativeCp );
+  zFullUTF = convertCpPathToUtf8( zFullCp );
+  sqlite3_snprintf( nFull, zFull, zFullUTF );
+  free( zFullUTF );
+  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
+}
+
+
+/*
 ** Open a file.
 */
 static int os2Open(
@@ -18335,18 +20967,31 @@ static int os2Open(
   int *pOutFlags                /* Status return flags */
 ){
   HFILE h;
-  ULONG ulFileAttribute = 0;
+  ULONG ulFileAttribute = FILE_NORMAL;
   ULONG ulOpenFlags = 0;
   ULONG ulOpenMode = 0;
   os2File *pFile = (os2File*)id;
   APIRET rc = NO_ERROR;
   ULONG ulAction;
+  char *zNameCp;
+  char zTmpname[CCHMAXPATH+1];    /* Buffer to hold name of temp file */
+
+  /* If the second argument to this function is NULL, generate a 
+  ** temporary file name to use 
+  */
+  if( !zName ){
+    int rc = getTempname(CCHMAXPATH+1, zTmpname);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    zName = zTmpname;
+  }
+
 
   memset( pFile, 0, sizeof(*pFile) );
 
   OSTRACE2( "OPEN want %d\n", flags );
 
-  /*ulOpenMode = flags & SQLITE_OPEN_READWRITE ? OPEN_ACCESS_READWRITE : OPEN_ACCESS_READONLY;*/
   if( flags & SQLITE_OPEN_READWRITE ){
     ulOpenMode |= OPEN_ACCESS_READWRITE;
     OSTRACE1( "OPEN read/write\n" );
@@ -18355,7 +21000,6 @@ static int os2Open(
     OSTRACE1( "OPEN read only\n" );
   }
 
-  /*ulOpenFlags = flags & SQLITE_OPEN_CREATE ? OPEN_ACTION_CREATE_IF_NEW : OPEN_ACTION_FAIL_IF_NEW;*/
   if( flags & SQLITE_OPEN_CREATE ){
     ulOpenFlags |= OPEN_ACTION_OPEN_IF_EXISTS | OPEN_ACTION_CREATE_IF_NEW;
     OSTRACE1( "OPEN open new/create\n" );
@@ -18364,7 +21008,6 @@ static int os2Open(
     OSTRACE1( "OPEN open existing\n" );
   }
 
-  /*ulOpenMode |= flags & SQLITE_OPEN_MAIN_DB ? OPEN_SHARE_DENYNONE : OPEN_SHARE_DENYWRITE;*/
   if( flags & SQLITE_OPEN_MAIN_DB ){
     ulOpenMode |= OPEN_SHARE_DENYNONE;
     OSTRACE1( "OPEN share read/write\n" );
@@ -18373,16 +21016,15 @@ static int os2Open(
     OSTRACE1( "OPEN share read only\n" );
   }
 
-  if( flags & (SQLITE_OPEN_TEMP_DB | SQLITE_OPEN_TEMP_JOURNAL
-               | SQLITE_OPEN_SUBJOURNAL) ){
+  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
     char pathUtf8[CCHMAXPATH];
-    /*ulFileAttribute = FILE_HIDDEN;  //for debugging, we want to make sure it is deleted*/
-    ulFileAttribute = FILE_NORMAL;
-    sqlite3OsFullPathname( pVfs, zName, CCHMAXPATH, pathUtf8 );
+#ifdef NDEBUG /* when debugging we want to make sure it is deleted */
+    ulFileAttribute = FILE_HIDDEN;
+#endif
+    os2FullPathname( pVfs, zName, CCHMAXPATH, pathUtf8 );
     pFile->pathToDel = convertUtf8PathToCp( pathUtf8 );
     OSTRACE1( "OPEN hidden/delete on close file attributes\n" );
   }else{
-    ulFileAttribute = FILE_ARCHIVED | FILE_NORMAL;
     pFile->pathToDel = NULL;
     OSTRACE1( "OPEN normal file attribute\n" );
   }
@@ -18392,7 +21034,7 @@ static int os2Open(
   ulOpenMode |= OPEN_FLAGS_FAIL_ON_ERROR;
   ulOpenMode |= OPEN_FLAGS_NOINHERIT;
 
-  char *zNameCp = convertUtf8PathToCp( zName );
+  zNameCp = convertUtf8PathToCp( zName );
   rc = DosOpen( (PSZ)zNameCp,
                 &h,
                 &ulAction,
@@ -18405,11 +21047,12 @@ static int os2Open(
   if( rc != NO_ERROR ){
     OSTRACE7( "OPEN Invalid handle rc=%d: zName=%s, ulAction=%#lx, ulAttr=%#lx, ulFlags=%#lx, ulMode=%#lx\n",
               rc, zName, ulAction, ulFileAttribute, ulOpenFlags, ulOpenMode );
-    free( pFile->pathToDel );
+    if( pFile->pathToDel )
+      free( pFile->pathToDel );
     pFile->pathToDel = NULL;
     if( flags & SQLITE_OPEN_READWRITE ){
       OSTRACE2( "OPEN %d Invalid handle\n", ((flags | SQLITE_OPEN_READONLY) & ~SQLITE_OPEN_READWRITE) );
-      return os2Open( 0, zName, id,
+      return os2Open( pVfs, zName, id,
                       ((flags | SQLITE_OPEN_READONLY) & ~SQLITE_OPEN_READWRITE),
                       pOutFlags );
     }else{
@@ -18431,18 +21074,18 @@ static int os2Open(
 /*
 ** Delete the named file.
 */
-int os2Delete(
+static int os2Delete(
   sqlite3_vfs *pVfs,                     /* Not used on os2 */
   const char *zFilename,                 /* Name of file to delete */
   int syncDir                            /* Not used on os2 */
 ){
   APIRET rc = NO_ERROR;
-  SimulateIOError(return SQLITE_IOERR_DELETE);
   char *zFilenameCp = convertUtf8PathToCp( zFilename );
+  SimulateIOError( return SQLITE_IOERR_DELETE );
   rc = DosDelete( (PSZ)zFilenameCp );
   free( zFilenameCp );
   OSTRACE2( "DELETE \"%s\"\n", zFilename );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
+  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_DELETE;
 }
 
 /*
@@ -18451,13 +21094,14 @@ int os2Delete(
 static int os2Access(
   sqlite3_vfs *pVfs,        /* Not used on os2 */
   const char *zFilename,    /* Name of file to check */
-  int flags                 /* Type of test to make on this file */
+  int flags,                /* Type of test to make on this file */
+  int *pOut                 /* Write results here */
 ){
   FILESTATUS3 fsts3ConfigInfo;
   APIRET rc = NO_ERROR;
+  char *zFilenameCp = convertUtf8PathToCp( zFilename );
 
   memset( &fsts3ConfigInfo, 0, sizeof(fsts3ConfigInfo) );
-  char *zFilenameCp = convertUtf8PathToCp( zFilename );
   rc = DosQueryPathInfo( (PSZ)zFilenameCp, FIL_STANDARD,
                          &fsts3ConfigInfo, sizeof(FILESTATUS3) );
   free( zFilenameCp );
@@ -18470,83 +21114,17 @@ static int os2Access(
       OSTRACE3( "ACCESS %s access of read and exists  rc=%d\n", zFilename, rc );
       break;
     case SQLITE_ACCESS_READWRITE:
-      rc = (fsts3ConfigInfo.attrFile & FILE_READONLY) == 0;
+      rc = (rc == NO_ERROR) && ( (fsts3ConfigInfo.attrFile & FILE_READONLY) == 0 );
       OSTRACE3( "ACCESS %s access of read/write  rc=%d\n", zFilename, rc );
       break;
     default:
       assert( !"Invalid flags argument" );
   }
-  return rc;
-}
-
-
-/*
-** Create a temporary file name in zBuf.  zBuf must be big enough to
-** hold at pVfs->mxPathname characters.
-*/
-static int os2GetTempname( sqlite3_vfs *pVfs, int nBuf, char *zBuf ){
-  static const unsigned char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  int i, j;
-  char zTempPathBuf[3];
-  PSZ zTempPath = (PSZ)&zTempPathBuf;
-  char *zTempPathUTF;
-  if( DosScanEnv( (PSZ)"TEMP", &zTempPath ) ){
-    if( DosScanEnv( (PSZ)"TMP", &zTempPath ) ){
-      if( DosScanEnv( (PSZ)"TMPDIR", &zTempPath ) ){
-           ULONG ulDriveNum = 0, ulDriveMap = 0;
-           DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap );
-           sprintf( (char*)zTempPath, "%c:", (char)( 'A' + ulDriveNum - 1 ) );
-      }
-    }
-  }
-  /* strip off a trailing slashes or backslashes, otherwise we would get *
-   * multiple (back)slashes which causes DosOpen() to fail               */
-  j = strlen(zTempPath);
-  while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/' ) ){
-    j--;
-  }
-  zTempPath[j] = '\0';
-  zTempPathUTF = convertCpPathToUtf8( zTempPath );
-  sqlite3_snprintf( nBuf-30, zBuf,
-                    "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPathUTF );
-  free( zTempPathUTF );
-  j = strlen( zBuf );
-  sqlite3_randomness( 20, &zBuf[j] );
-  for( i = 0; i < 20; i++, j++ ){
-    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
-  }
-  zBuf[j] = 0;
-  OSTRACE2( "TEMP FILENAME: %s\n", zBuf );
+  *pOut = rc;
   return SQLITE_OK;
 }
 
 
-/*
-** Turn a relative pathname into a full pathname.  Write the full
-** pathname into zFull[].  zFull[] will be at least pVfs->mxPathname
-** bytes in size.
-*/
-static int os2FullPathname(
-  sqlite3_vfs *pVfs,          /* Pointer to vfs object */
-  const char *zRelative,      /* Possibly relative input path */
-  int nFull,                  /* Size of output buffer in bytes */
-  char *zFull                 /* Output buffer */
-){
-  char *zRelativeCp = convertUtf8PathToCp( zRelative );
-  char zFullCp[CCHMAXPATH];
-  char *zFullUTF;
-  APIRET rc = DosQueryPathInfo( zRelativeCp, FIL_QUERYFULLNAME, zFullCp,
-                                CCHMAXPATH );
-  free( zRelativeCp );
-  zFullUTF = convertCpPathToUtf8( zFullCp );
-  sqlite3_snprintf( nFull, zFull, zFullUTF );
-  free( zFullUTF );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
-}
-
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
 /*
 ** Interfaces for opening a shared library, finding entry points
@@ -18572,7 +21150,7 @@ static void *os2DlOpen(sqlite3_vfs *pVfs, const char *zFilename){
 static void os2DlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
 /* no-op */
 }
-void *os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
+static void *os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
   PFN pfn;
   APIRET rc;
   rc = DosQueryProcAddr((HMODULE)pHandle, 0L, zSymbol, &pfn);
@@ -18586,7 +21164,7 @@ void *os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
   }
   return rc != NO_ERROR ? 0 : (void*)pfn;
 }
-void os2DlClose(sqlite3_vfs *pVfs, void *pHandle){
+static void os2DlClose(sqlite3_vfs *pVfs, void *pHandle){
   DosFreeModule((HMODULE)pHandle);
 }
 #else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
@@ -18601,9 +21179,13 @@ void os2DlClose(sqlite3_vfs *pVfs, void *pHandle){
 ** Write up to nBuf bytes of randomness into zBuf.
 */
 static int os2Randomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf ){
-  ULONG sizeofULong = sizeof(ULONG);
   int n = 0;
-  if( sizeof(DATETIME) <= nBuf - n ){
+#if defined(SQLITE_TEST)
+  n = nBuf;
+  memset(zBuf, 0, nBuf);
+#else
+  int sizeofULong = sizeof(ULONG);
+  if( (int)sizeof(DATETIME) <= nBuf - n ){
     DATETIME x;
     DosGetDateTime(&x);
     memcpy(&zBuf[n], &x, sizeof(x));
@@ -18650,6 +21232,7 @@ static int os2Randomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf ){
       n += sizeofULong;
     }
   }
+#endif
 
   return n;
 }
@@ -18715,13 +21298,14 @@ int os2CurrentTime( sqlite3_vfs *pVfs, double *prNow ){
   return 0;
 }
 
+static int os2GetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+  return 0;
+}
+
 /*
-** Return a pointer to the sqlite3DefaultVfs structure.   We use
-** a function rather than give the structure global scope because
-** some compilers (MSVC) do not allow forward declarations of
-** initialized structures.
+** Initialize and deinitialize the operating system interface.
 */
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
+SQLITE_API int sqlite3_os_init(void){
   static sqlite3_vfs os2Vfs = {
     1,                 /* iVersion */
     sizeof(os2File),   /* szOsFile */
@@ -18733,7 +21317,6 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
     os2Open,           /* xOpen */
     os2Delete,         /* xDelete */
     os2Access,         /* xAccess */
-    os2GetTempname,    /* xGetTempname */
     os2FullPathname,   /* xFullPathname */
     os2DlOpen,         /* xDlOpen */
     os2DlError,        /* xDlError */
@@ -18741,13 +21324,19 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
     os2DlClose,        /* xDlClose */
     os2Randomness,     /* xRandomness */
     os2Sleep,          /* xSleep */
-    os2CurrentTime     /* xCurrentTime */
+    os2CurrentTime,    /* xCurrentTime */
+    os2GetLastError    /* xGetLastError */
   };
-
-  return &os2Vfs;
+  sqlite3_vfs_register(&os2Vfs, 1);
+  initUconvObjects();
+  return SQLITE_OK;
+}
+SQLITE_API int sqlite3_os_end(void){
+  freeUconvObjects();
+  return SQLITE_OK;
 }
 
-#endif /* OS_OS2 */
+#endif /* SQLITE_OS_OS2 */
 
 /************** End of os_os2.c **********************************************/
 /************** Begin file os_unix.c *****************************************/
@@ -18763,13 +21352,77 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
 **
 ******************************************************************************
 **
-** This file contains code that is specific to Unix systems.
-*/
-#if OS_UNIX              /* This file is used on unix only */
-
-#include <qconfig.h>
+** This file contains the VFS implementation for unix-like operating systems
+** include Linux, MacOSX, *BSD, QNX, VxWorks, AIX, HPUX, and others.
+**
+** There are actually several different VFS implementations in this file.
+** The differences are in the way that file locking is done.  The default
+** implementation uses Posix Advisory Locks.  Alternative implementations
+** use flock(), dot-files, various proprietary locking schemas, or simply
+** skip locking all together.
+**
+** This source file is organized into divisions where the logic for various
+** subfunctions is contained within the appropriate division.  PLEASE
+** KEEP THE STRUCTURE OF THIS FILE INTACT.  New code should be placed
+** in the correct division and should be clearly labeled.
+**
+** The layout of divisions is as follows:
+**
+**   *  General-purpose declarations and utility functions.
+**   *  Unique file ID logic used by VxWorks.
+**   *  Various locking primitive implementations (all except proxy locking):
+**      + for Posix Advisory Locks
+**      + for no-op locks
+**      + for dot-file locks
+**      + for flock() locking
+**      + for named semaphore locks (VxWorks only)
+**      + for AFP filesystem locks (MacOSX only)
+**   *  sqlite3_file methods not associated with locking.
+**   *  Definitions of sqlite3_io_methods objects for all locking
+**      methods plus "finder" functions for each locking method.
+**   *  sqlite3_vfs method implementations.
+**   *  Locking primitives for the proxy uber-locking-method. (MacOSX only)
+**   *  Definitions of sqlite3_vfs objects for all locking methods
+**      plus implementations of sqlite3_os_init() and sqlite3_os_end().
+*/
+#if SQLITE_OS_UNIX              /* This file is used on unix only */
+
+/*
+** There are various methods for file locking used for concurrency
+** control:
+**
+**   1. POSIX locking (the default),
+**   2. No locking,
+**   3. Dot-file locking,
+**   4. flock() locking,
+**   5. AFP locking (OSX only),
+**   6. Named POSIX semaphores (VXWorks only),
+**   7. proxy locking. (OSX only)
+**
+** Styles 4, 5, and 7 are only available of SQLITE_ENABLE_LOCKING_STYLE
+** is defined to 1.  The SQLITE_ENABLE_LOCKING_STYLE also enables automatic
+** selection of the appropriate locking style based on the filesystem
+** where the database is located.  
+*/
+#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
+#  if defined(__APPLE__)
+#    define SQLITE_ENABLE_LOCKING_STYLE 1
+#  else
+#    define SQLITE_ENABLE_LOCKING_STYLE 0
+#  endif
+#endif
 
-/* #define SQLITE_ENABLE_LOCKING_STYLE 0 */
+/*
+** Define the OS_VXWORKS pre-processor macro to 1 if building on 
+** vxworks, or 0 otherwise.
+*/
+#ifndef OS_VXWORKS
+#  if defined(__RTP__) || defined(_WRS_KERNEL)
+#    define OS_VXWORKS 1
+#  else
+#    define OS_VXWORKS 0
+#  endif
+#endif
 
 /*
 ** These #defines should enable >2GB file support on Posix if the
@@ -18783,6 +21436,11 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
 ** without this option, LFS is enable.  But LFS does not exist in the kernel
 ** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
 ** portability you should omit LFS.
+**
+** The previous paragraph was written in 2005.  (This paragraph is written
+** on 2008-11-28.) These days, all Linux kernels support large files, so
+** you should probably leave LFS enabled.  But some embedded platforms might
+** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
 */
 #ifndef SQLITE_DISABLE_LFS
 # define _LARGE_FILE       1
@@ -18799,23 +21457,26 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
-#ifdef VXWORKS
-# include <sys/times.h>
-#else
-# include <sys/time.h>
-#endif
+#include <sys/time.h>
 #include <errno.h>
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-#include <sys/ioctl.h>
-#include <sys/param.h>
-#include <sys/mount.h>
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+# include <sys/ioctl.h>
+# if OS_VXWORKS
+#  include <semaphore.h>
+#  include <limits.h>
+# else
+#  include <sys/file.h>
+#  include <sys/param.h>
+#  include <sys/mount.h>
+# endif
 #endif /* SQLITE_ENABLE_LOCKING_STYLE */
 
 /*
 ** If we are to be thread-safe, include the pthreads header and define
 ** the SQLITE_UNIX_THREADS macro.
 */
-#ifndef QT_NO_THREAD
+#if SQLITE_THREADSAFE
 # define SQLITE_UNIX_THREADS 1
 #endif
 
@@ -18827,38 +21488,89 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
 #endif
 
 /*
+ ** Default permissions when creating auto proxy dir
+ */
+#ifndef SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+# define SQLITE_DEFAULT_PROXYDIR_PERMISSIONS 0755
+#endif
+
+/*
 ** Maximum supported path-length.
 */
 #define MAX_PATHNAME 512
 
+/*
+** Only set the lastErrno if the error code is a real error and not 
+** a normal expected return code of SQLITE_BUSY or SQLITE_OK
+*/
+#define IS_LOCK_ERROR(x)  ((x != SQLITE_OK) && (x != SQLITE_BUSY))
+
 
 /*
-** The unixFile structure is subclass of sqlite3_file specific for the unix
-** protability layer.
+** Sometimes, after a file handle is closed by SQLite, the file descriptor
+** cannot be closed immediately. In these cases, instances of the following
+** structure are used to store the file descriptor while waiting for an
+** opportunity to either close or reuse it.
+*/
+typedef struct UnixUnusedFd UnixUnusedFd;
+struct UnixUnusedFd {
+  int fd;                   /* File descriptor to close */
+  int flags;                /* Flags this file descriptor was opened with */
+  UnixUnusedFd *pNext;      /* Next unused file descriptor on same file */
+};
+
+/*
+** The unixFile structure is subclass of sqlite3_file specific to the unix
+** VFS implementations.
 */
 typedef struct unixFile unixFile;
 struct unixFile {
   sqlite3_io_methods const *pMethod;  /* Always the first entry */
+  struct unixOpenCnt *pOpen;       /* Info about all open fd's on this inode */
+  struct unixLockInfo *pLock;      /* Info about locks on this inode */
+  int h;                           /* The file descriptor */
+  int dirfd;                       /* File descriptor for the directory */
+  unsigned char locktype;          /* The type of lock held on this fd */
+  int lastErrno;                   /* The unix errno from the last I/O error */
+  void *lockingContext;            /* Locking style specific state */
+  UnixUnusedFd *pUnused;           /* Pre-allocated UnixUnusedFd */
+  int fileFlags;                   /* Miscellanous flags */
+#if SQLITE_ENABLE_LOCKING_STYLE
+  int openFlags;                   /* The flags specified at open() */
+#endif
+#if SQLITE_THREADSAFE && defined(__linux__)
+  pthread_t tid;                   /* The thread that "owns" this unixFile */
+#endif
+#if OS_VXWORKS
+  int isDelete;                    /* Delete on close if true */
+  struct vxworksFileId *pId;       /* Unique file ID */
+#endif
+#ifndef NDEBUG
+  /* The next group of variables are used to track whether or not the
+  ** transaction counter in bytes 24-27 of database files are updated
+  ** whenever any part of the database changes.  An assertion fault will
+  ** occur if a file is updated without also updating the transaction
+  ** counter.  This test is made to avoid new problems similar to the
+  ** one described by ticket #3584. 
+  */
+  unsigned char transCntrChng;   /* True if the transaction counter changed */
+  unsigned char dbUpdate;        /* True if any part of database file changed */
+  unsigned char inNormalWrite;   /* True if in a normal write operation */
+#endif
 #ifdef SQLITE_TEST
   /* In test mode, increase the size of this structure a bit so that 
   ** it is larger than the struct CrashFile defined in test6.c.
   */
   char aPadding[32];
 #endif
-  struct openCnt *pOpen;    /* Info about all open fd's on this inode */
-  struct lockInfo *pLock;   /* Info about locks on this inode */
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-  void *lockingContext;     /* Locking style specific state */
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
-  int h;                    /* The file descriptor */
-  unsigned char locktype;   /* The type of lock held on this fd */
-  int dirfd;                /* File descriptor for the directory */
-#if SQLITE_THREADSAFE
-  pthread_t tid;            /* The thread that "owns" this unixFile */
-#endif
 };
 
 /*
+** The following macros define bits in unixFile.fileFlags
+*/
+#define SQLITE_WHOLE_FILE_LOCKING  0x0001   /* Use whole-file locking */
+
+/*
 ** Include code that is common to all os_*.c files
 */
 /************** Include os_common.h in the middle of os_unix.c ***************/
@@ -18881,7 +21593,11 @@ struct unixFile {
 **
 ** This file should be #included by the os_*.c files only.  It is not a
 ** general purpose header file.
+**
+** $Id: os_common.h,v 1.38 2009/02/24 18:40:50 danielk1977 Exp $
 */
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
 
 /*
 ** At least two bugs have slipped in because we changed the MEMORY_DEBUG
@@ -18892,15 +21608,6 @@ struct unixFile {
 # error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
 #endif
 
-
-/*
- * When testing, this global variable stores the location of the
- * pending-byte in the database file.
- */
-#ifdef SQLITE_TEST
-SQLITE_API unsigned int sqlite3_pending_byte = 0x40000000;
-#endif
-
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE int sqlite3OSTrace = 0;
 #define OSTRACE1(X)         if( sqlite3OSTrace ) sqlite3DebugPrintf(X)
@@ -18927,22 +21634,113 @@ SQLITE_PRIVATE int sqlite3OSTrace = 0;
 ** on i486 hardware.
 */
 #ifdef SQLITE_PERFORMANCE_TRACE
-__inline__ unsigned long long int hwtime(void){
-  unsigned long long int x;
-  __asm__("rdtsc\n\t"
-          "mov %%edx, %%ecx\n\t"
-          :"=A" (x));
-  return x;
-}
-static unsigned long long int g_start;
-static unsigned int elapse;
-#define TIMER_START       g_start=hwtime()
-#define TIMER_END         elapse=hwtime()-g_start
-#define TIMER_ELAPSED     elapse
+
+/* 
+** hwtime.h contains inline assembler code for implementing 
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+**
+** $Id: hwtime.h,v 1.3 2008/08/01 14:33:15 shane Exp $
+*/
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value.  This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+      (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+  #if defined(__GNUC__)
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+     unsigned int lo, hi;
+     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+     return (sqlite_uint64)hi << 32 | lo;
+  }
+
+  #elif defined(_MSC_VER)
+
+  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+     __asm {
+        rdtsc
+        ret       ; return value at EDX:EAX
+     }
+  }
+
+  #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long val;
+      __asm__ __volatile__ ("rdtsc" : "=A" (val));
+      return val;
+  }
+ 
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long long retval;
+      unsigned long junk;
+      __asm__ __volatile__ ("\n\
+          1:      mftbu   %1\n\
+                  mftb    %L0\n\
+                  mftbu   %0\n\
+                  cmpw    %0,%1\n\
+                  bne     1b"
+                  : "=r" (retval), "=r" (junk));
+      return retval;
+  }
+
+#else
+
+  #error Need implementation of sqlite3Hwtime() for your platform.
+
+  /*
+  ** To compile without implementing sqlite3Hwtime() for your platform,
+  ** you can remove the above #error and use the following
+  ** stub function.  You will lose timing support for many
+  ** of the debugging and testing utilities, but it should at
+  ** least compile and run.
+  */
+SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START       g_start=sqlite3Hwtime()
+#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED     g_elapsed
 #else
 #define TIMER_START
 #define TIMER_END
-#define TIMER_ELAPSED     0
+#define TIMER_ELAPSED     ((sqlite_uint64)0)
 #endif
 
 /*
@@ -18995,6 +21793,8 @@ SQLITE_API int sqlite3_open_file_count = 0;
 #define OpenCounter(X)
 #endif
 
+#endif /* !defined(_OS_COMMON_H_) */
+
 /************** End of os_common.h *******************************************/
 /************** Continuing where we left off in os_unix.c ********************/
 
@@ -19035,271 +21835,52 @@ SQLITE_API int sqlite3_open_file_count = 0;
 #define threadid 0
 #endif
 
-/*
-** Set or check the unixFile.tid field.  This field is set when an unixFile
-** is first opened.  All subsequent uses of the unixFile verify that the
-** same thread is operating on the unixFile.  Some operating systems do
-** not allow locks to be overridden by other threads and that restriction
-** means that sqlite3* database handles cannot be moved from one thread
-** to another.  This logic makes sure a user does not try to do that
-** by mistake.
-**
-** Version 3.3.1 (2006-01-15):  unixFile can be moved from one thread to
-** another as long as we are running on a system that supports threads
-** overriding each others locks (which now the most common behavior)
-** or if no locks are held.  But the unixFile.pLock field needs to be
-** recomputed because its key includes the thread-id.  See the 
-** transferOwnership() function below for additional information
-*/
-#if SQLITE_THREADSAFE
-# define SET_THREADID(X)   (X)->tid = pthread_self()
-# define CHECK_THREADID(X) (threadsOverrideEachOthersLocks==0 && \
-                            !pthread_equal((X)->tid, pthread_self()))
-#else
-# define SET_THREADID(X)
-# define CHECK_THREADID(X) 0
-#endif
 
 /*
-** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
-** section 6.5.2.2 lines 483 through 490 specify that when a process
-** sets or clears a lock, that operation overrides any prior locks set
-** by the same process.  It does not explicitly say so, but this implies
-** that it overrides locks set by the same process using a different
-** file descriptor.  Consider this test case:
-**
-**       int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
-**       int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
-**
-** Suppose ./file1 and ./file2 are really the same file (because
-** one is a hard or symbolic link to the other) then if you set
-** an exclusive lock on fd1, then try to get an exclusive lock
-** on fd2, it works.  I would have expected the second lock to
-** fail since there was already a lock on the file due to fd1.
-** But not so.  Since both locks came from the same process, the
-** second overrides the first, even though they were on different
-** file descriptors opened on different file names.
-**
-** Bummer.  If you ask me, this is broken.  Badly broken.  It means
-** that we cannot use POSIX locks to synchronize file access among
-** competing threads of the same process.  POSIX locks will work fine
-** to synchronize access for threads in separate processes, but not
-** threads within the same process.
-**
-** To work around the problem, SQLite has to manage file locks internally
-** on its own.  Whenever a new database is opened, we have to find the
-** specific inode of the database file (the inode is determined by the
-** st_dev and st_ino fields of the stat structure that fstat() fills in)
-** and check for locks already existing on that inode.  When locks are
-** created or removed, we have to look at our own internal record of the
-** locks to see if another thread has previously set a lock on that same
-** inode.
-**
-** The sqlite3_file structure for POSIX is no longer just an integer file
-** descriptor.  It is now a structure that holds the integer file
-** descriptor and a pointer to a structure that describes the internal
-** locks on the corresponding inode.  There is one locking structure
-** per inode, so if the same inode is opened twice, both unixFile structures
-** point to the same locking structure.  The locking structure keeps
-** a reference count (so we will know when to delete it) and a "cnt"
-** field that tells us its internal lock status.  cnt==0 means the
-** file is unlocked.  cnt==-1 means the file has an exclusive lock.
-** cnt>0 means there are cnt shared locks on the file.
-**
-** Any attempt to lock or unlock a file first checks the locking
-** structure.  The fcntl() system call is only invoked to set a 
-** POSIX lock if the internal lock structure transitions between
-** a locked and an unlocked state.
-**
-** 2004-Jan-11:
-** More recent discoveries about POSIX advisory locks.  (The more
-** I discover, the more I realize the a POSIX advisory locks are
-** an abomination.)
-**
-** If you close a file descriptor that points to a file that has locks,
-** all locks on that file that are owned by the current process are
-** released.  To work around this problem, each unixFile structure contains
-** a pointer to an openCnt structure.  There is one openCnt structure
-** per open inode, which means that multiple unixFile can point to a single
-** openCnt.  When an attempt is made to close an unixFile, if there are
-** other unixFile open on the same inode that are holding locks, the call
-** to close() the file descriptor is deferred until all of the locks clear.
-** The openCnt structure keeps a list of file descriptors that need to
-** be closed and that list is walked (and cleared) when the last lock
-** clears.
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect the unixOpenCnt, unixLockInfo and
+** vxworksFileId objects used by this file, all of which may be 
+** shared by multiple threads.
 **
-** First, under Linux threads, because each thread has a separate
-** process ID, lock operations in one thread do not override locks
-** to the same file in other threads.  Linux threads behave like
-** separate processes in this respect.  But, if you close a file
-** descriptor in linux threads, all locks are cleared, even locks
-** on other threads and even though the other threads have different
-** process IDs.  Linux threads is inconsistent in this respect.
-** (I'm beginning to think that linux threads is an abomination too.)
-** The consequence of this all is that the hash table for the lockInfo
-** structure has to include the process id as part of its key because
-** locks in different threads are treated as distinct.  But the 
-** openCnt structure should not include the process id in its
-** key because close() clears lock on all threads, not just the current
-** thread.  Were it not for this goofiness in linux threads, we could
-** combine the lockInfo and openCnt structures into a single structure.
-**
-** 2004-Jun-28:
-** On some versions of linux, threads can override each others locks.
-** On others not.  Sometimes you can change the behavior on the same
-** system by setting the LD_ASSUME_KERNEL environment variable.  The
-** POSIX standard is silent as to which behavior is correct, as far
-** as I can tell, so other versions of unix might show the same
-** inconsistency.  There is no little doubt in my mind that posix
-** advisory locks and linux threads are profoundly broken.
-**
-** To work around the inconsistencies, we have to test at runtime 
-** whether or not threads can override each others locks.  This test
-** is run once, the first time any lock is attempted.  A static 
-** variable is set to record the results of this test for future
-** use.
-*/
-
-/*
-** An instance of the following structure serves as the key used
-** to locate a particular lockInfo structure given its inode.
+** Function unixMutexHeld() is used to assert() that the global mutex 
+** is held when required. This function is only used as part of assert() 
+** statements. e.g.
 **
-** If threads cannot override each others locks, then we set the
-** lockKey.tid field to the thread ID.  If threads can override
-** each others locks then tid is always set to zero.  tid is omitted
-** if we compile without threading support.
+**   unixEnterMutex()
+**     assert( unixMutexHeld() );
+**   unixEnterLeave()
 */
-struct lockKey {
-  dev_t dev;       /* Device number */
-  ino_t ino;       /* Inode number */
-#if SQLITE_THREADSAFE
-  pthread_t tid;   /* Thread ID or zero if threads can override each other */
+static void unixEnterMutex(void){
+  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+static void unixLeaveMutex(void){
+  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#ifdef SQLITE_DEBUG
+static int unixMutexHeld(void) {
+  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
 #endif
-};
-
-/*
-** An instance of the following structure is allocated for each open
-** inode on each thread with a different process ID.  (Threads have
-** different process IDs on linux, but not on most other unixes.)
-**
-** A single inode can have multiple file descriptors, so each unixFile
-** structure contains a pointer to an instance of this object and this
-** object keeps a count of the number of unixFile pointing to it.
-*/
-struct lockInfo {
-  struct lockKey key;  /* The lookup key */
-  int cnt;             /* Number of SHARED locks held */
-  int locktype;        /* One of SHARED_LOCK, RESERVED_LOCK etc. */
-  int nRef;            /* Number of pointers to this structure */
-};
-
-/*
-** An instance of the following structure serves as the key used
-** to locate a particular openCnt structure given its inode.  This
-** is the same as the lockKey except that the thread ID is omitted.
-*/
-struct openKey {
-  dev_t dev;   /* Device number */
-  ino_t ino;   /* Inode number */
-};
-
-/*
-** An instance of the following structure is allocated for each open
-** inode.  This structure keeps track of the number of locks on that
-** inode.  If a close is attempted against an inode that is holding
-** locks, the close is deferred until all locks clear by adding the
-** file descriptor to be closed to the pending list.
-*/
-struct openCnt {
-  struct openKey key;   /* The lookup key */
-  int nRef;             /* Number of pointers to this structure */
-  int nLock;            /* Number of outstanding locks */
-  int nPending;         /* Number of pending close() operations */
-  int *aPending;        /* Malloced space holding fd's awaiting a close() */
-};
 
-/* 
-** These hash tables map inodes and file descriptors (really, lockKey and
-** openKey structures) into lockInfo and openCnt structures.  Access to 
-** these hash tables must be protected by a mutex.
-*/
-static Hash lockHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0};
-static Hash openHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0};
-
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-/*
-** The locking styles are associated with the different file locking
-** capabilities supported by different file systems.  
-**
-** POSIX locking style fully supports shared and exclusive byte-range locks 
-** ADP locking only supports exclusive byte-range locks
-** FLOCK only supports a single file-global exclusive lock
-** DOTLOCK isn't a true locking style, it refers to the use of a special
-**   file named the same as the database file with a '.lock' extension, this
-**   can be used on file systems that do not offer any reliable file locking
-** NO locking means that no locking will be attempted, this is only used for
-**   read-only file systems currently
-** UNSUPPORTED means that no locking will be attempted, this is only used for
-**   file systems that are known to be unsupported
-*/
-typedef enum {
-  posixLockingStyle = 0,       /* standard posix-advisory locks */
-  afpLockingStyle,             /* use afp locks */
-  flockLockingStyle,           /* use flock() */
-  dotlockLockingStyle,         /* use <file>.lock files */
-  noLockingStyle,              /* useful for read-only file system */
-  unsupportedLockingStyle      /* indicates unsupported file system */
-} sqlite3LockingStyle;
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
 
+#ifdef SQLITE_DEBUG
 /*
-** Helper functions to obtain and relinquish the global mutex.
+** Helper function for printing out trace information from debugging
+** binaries. This returns the string represetation of the supplied
+** integer lock-type.
 */
-static void enterMutex(){
-  sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-static void leaveMutex(){
-  sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
+static const char *locktypeName(int locktype){
+  switch( locktype ){
+    case NO_LOCK: return "NONE";
+    case SHARED_LOCK: return "SHARED";
+    case RESERVED_LOCK: return "RESERVED";
+    case PENDING_LOCK: return "PENDING";
+    case EXCLUSIVE_LOCK: return "EXCLUSIVE";
+  }
+  return "ERROR";
 }
-
-#if SQLITE_THREADSAFE
-/*
-** This variable records whether or not threads can override each others
-** locks.
-**
-**    0:  No.  Threads cannot override each others locks.
-**    1:  Yes.  Threads can override each others locks.
-**   -1:  We don't know yet.
-**
-** On some systems, we know at compile-time if threads can override each
-** others locks.  On those systems, the SQLITE_THREAD_OVERRIDE_LOCK macro
-** will be set appropriately.  On other systems, we have to check at
-** runtime.  On these latter systems, SQLTIE_THREAD_OVERRIDE_LOCK is
-** undefined.
-**
-** This variable normally has file scope only.  But during testing, we make
-** it a global so that the test code can change its value in order to verify
-** that the right stuff happens in either case.
-*/
-#ifndef SQLITE_THREAD_OVERRIDE_LOCK
-# define SQLITE_THREAD_OVERRIDE_LOCK -1
-#endif
-#ifdef SQLITE_TEST
-int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK;
-#else
-static int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK;
 #endif
 
-/*
-** This structure holds information passed into individual test
-** threads by the testThreadLockingBehavior() routine.
-*/
-struct threadTestData {
-  int fd;                /* File to be locked */
-  struct flock lock;     /* The locking operation */
-  int result;            /* Result of the locking operation */
-};
-
 #ifdef SQLITE_LOCK_TRACE
 /*
 ** Print out information about all locking operations.
@@ -19359,19 +21940,470 @@ static int lockTrace(int fd, int op, struct flock *p){
 #define fcntl lockTrace
 #endif /* SQLITE_LOCK_TRACE */
 
+
+
+/*
+** This routine translates a standard POSIX errno code into something
+** useful to the clients of the sqlite3 functions.  Specifically, it is
+** intended to translate a variety of "try again" errors into SQLITE_BUSY
+** and a variety of "please close the file descriptor NOW" errors into 
+** SQLITE_IOERR
+** 
+** Errors during initialization of locks, or file system support for locks,
+** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
+*/
+static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
+  switch (posixError) {
+  case 0: 
+    return SQLITE_OK;
+    
+  case EAGAIN:
+  case ETIMEDOUT:
+  case EBUSY:
+  case EINTR:
+  case ENOLCK:  
+    /* random NFS retry error, unless during file system support 
+     * introspection, in which it actually means what it says */
+    return SQLITE_BUSY;
+    
+  case EACCES: 
+    /* EACCES is like EAGAIN during locking operations, but not any other time*/
+    if( (sqliteIOErr == SQLITE_IOERR_LOCK) || 
+	(sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
+	(sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
+	(sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
+      return SQLITE_BUSY;
+    }
+    /* else fall through */
+  case EPERM: 
+    return SQLITE_PERM;
+    
+  case EDEADLK:
+    return SQLITE_IOERR_BLOCKED;
+    
+#if EOPNOTSUPP!=ENOTSUP
+  case EOPNOTSUPP: 
+    /* something went terribly awry, unless during file system support 
+     * introspection, in which it actually means what it says */
+#endif
+#ifdef ENOTSUP
+  case ENOTSUP: 
+    /* invalid fd, unless during file system support introspection, in which 
+     * it actually means what it says */
+#endif
+  case EIO:
+  case EBADF:
+  case EINVAL:
+  case ENOTCONN:
+  case ENODEV:
+  case ENXIO:
+  case ENOENT:
+  case ESTALE:
+  case ENOSYS:
+    /* these should force the client to close the file and reconnect */
+    
+  default: 
+    return sqliteIOErr;
+  }
+}
+
+
+
+/******************************************************************************
+****************** Begin Unique File ID Utility Used By VxWorks ***************
+**
+** On most versions of unix, we can get a unique ID for a file by concatenating
+** the device number and the inode number.  But this does not work on VxWorks.
+** On VxWorks, a unique file id must be based on the canonical filename.
+**
+** A pointer to an instance of the following structure can be used as a
+** unique file ID in VxWorks.  Each instance of this structure contains
+** a copy of the canonical filename.  There is also a reference count.  
+** The structure is reclaimed when the number of pointers to it drops to
+** zero.
+**
+** There are never very many files open at one time and lookups are not
+** a performance-critical path, so it is sufficient to put these
+** structures on a linked list.
+*/
+struct vxworksFileId {
+  struct vxworksFileId *pNext;  /* Next in a list of them all */
+  int nRef;                     /* Number of references to this one */
+  int nName;                    /* Length of the zCanonicalName[] string */
+  char *zCanonicalName;         /* Canonical filename */
+};
+
+#if OS_VXWORKS
+/* 
+** All unique filenames are held on a linked list headed by this
+** variable:
+*/
+static struct vxworksFileId *vxworksFileList = 0;
+
+/*
+** Simplify a filename into its canonical form
+** by making the following changes:
+**
+**  * removing any trailing and duplicate /
+**  * convert /./ into just /
+**  * convert /A/../ where A is any simple name into just /
+**
+** Changes are made in-place.  Return the new name length.
+**
+** The original filename is in z[0..n-1].  Return the number of
+** characters in the simplified name.
+*/
+static int vxworksSimplifyName(char *z, int n){
+  int i, j;
+  while( n>1 && z[n-1]=='/' ){ n--; }
+  for(i=j=0; i<n; i++){
+    if( z[i]=='/' ){
+      if( z[i+1]=='/' ) continue;
+      if( z[i+1]=='.' && i+2<n && z[i+2]=='/' ){
+        i += 1;
+        continue;
+      }
+      if( z[i+1]=='.' && i+3<n && z[i+2]=='.' && z[i+3]=='/' ){
+        while( j>0 && z[j-1]!='/' ){ j--; }
+        if( j>0 ){ j--; }
+        i += 2;
+        continue;
+      }
+    }
+    z[j++] = z[i];
+  }
+  z[j] = 0;
+  return j;
+}
+
+/*
+** Find a unique file ID for the given absolute pathname.  Return
+** a pointer to the vxworksFileId object.  This pointer is the unique
+** file ID.
+**
+** The nRef field of the vxworksFileId object is incremented before
+** the object is returned.  A new vxworksFileId object is created
+** and added to the global list if necessary.
+**
+** If a memory allocation error occurs, return NULL.
+*/
+static struct vxworksFileId *vxworksFindFileId(const char *zAbsoluteName){
+  struct vxworksFileId *pNew;         /* search key and new file ID */
+  struct vxworksFileId *pCandidate;   /* For looping over existing file IDs */
+  int n;                              /* Length of zAbsoluteName string */
+
+  assert( zAbsoluteName[0]=='/' );
+  n = (int)strlen(zAbsoluteName);
+  pNew = sqlite3_malloc( sizeof(*pNew) + (n+1) );
+  if( pNew==0 ) return 0;
+  pNew->zCanonicalName = (char*)&pNew[1];
+  memcpy(pNew->zCanonicalName, zAbsoluteName, n+1);
+  n = vxworksSimplifyName(pNew->zCanonicalName, n);
+
+  /* Search for an existing entry that matching the canonical name.
+  ** If found, increment the reference count and return a pointer to
+  ** the existing file ID.
+  */
+  unixEnterMutex();
+  for(pCandidate=vxworksFileList; pCandidate; pCandidate=pCandidate->pNext){
+    if( pCandidate->nName==n 
+     && memcmp(pCandidate->zCanonicalName, pNew->zCanonicalName, n)==0
+    ){
+       sqlite3_free(pNew);
+       pCandidate->nRef++;
+       unixLeaveMutex();
+       return pCandidate;
+    }
+  }
+
+  /* No match was found.  We will make a new file ID */
+  pNew->nRef = 1;
+  pNew->nName = n;
+  pNew->pNext = vxworksFileList;
+  vxworksFileList = pNew;
+  unixLeaveMutex();
+  return pNew;
+}
+
+/*
+** Decrement the reference count on a vxworksFileId object.  Free
+** the object when the reference count reaches zero.
+*/
+static void vxworksReleaseFileId(struct vxworksFileId *pId){
+  unixEnterMutex();
+  assert( pId->nRef>0 );
+  pId->nRef--;
+  if( pId->nRef==0 ){
+    struct vxworksFileId **pp;
+    for(pp=&vxworksFileList; *pp && *pp!=pId; pp = &((*pp)->pNext)){}
+    assert( *pp==pId );
+    *pp = pId->pNext;
+    sqlite3_free(pId);
+  }
+  unixLeaveMutex();
+}
+#endif /* OS_VXWORKS */
+/*************** End of Unique File ID Utility Used By VxWorks ****************
+******************************************************************************/
+
+
+/******************************************************************************
+*************************** Posix Advisory Locking ****************************
+**
+** POSIX advisory locks are broken by design.  ANSI STD 1003.1 (1996)
+** section 6.5.2.2 lines 483 through 490 specify that when a process
+** sets or clears a lock, that operation overrides any prior locks set
+** by the same process.  It does not explicitly say so, but this implies
+** that it overrides locks set by the same process using a different
+** file descriptor.  Consider this test case:
+**
+**       int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
+**       int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
+**
+** Suppose ./file1 and ./file2 are really the same file (because
+** one is a hard or symbolic link to the other) then if you set
+** an exclusive lock on fd1, then try to get an exclusive lock
+** on fd2, it works.  I would have expected the second lock to
+** fail since there was already a lock on the file due to fd1.
+** But not so.  Since both locks came from the same process, the
+** second overrides the first, even though they were on different
+** file descriptors opened on different file names.
+**
+** This means that we cannot use POSIX locks to synchronize file access
+** among competing threads of the same process.  POSIX locks will work fine
+** to synchronize access for threads in separate processes, but not
+** threads within the same process.
+**
+** To work around the problem, SQLite has to manage file locks internally
+** on its own.  Whenever a new database is opened, we have to find the
+** specific inode of the database file (the inode is determined by the
+** st_dev and st_ino fields of the stat structure that fstat() fills in)
+** and check for locks already existing on that inode.  When locks are
+** created or removed, we have to look at our own internal record of the
+** locks to see if another thread has previously set a lock on that same
+** inode.
+**
+** (Aside: The use of inode numbers as unique IDs does not work on VxWorks.
+** For VxWorks, we have to use the alternative unique ID system based on
+** canonical filename and implemented in the previous division.)
+**
+** The sqlite3_file structure for POSIX is no longer just an integer file
+** descriptor.  It is now a structure that holds the integer file
+** descriptor and a pointer to a structure that describes the internal
+** locks on the corresponding inode.  There is one locking structure
+** per inode, so if the same inode is opened twice, both unixFile structures
+** point to the same locking structure.  The locking structure keeps
+** a reference count (so we will know when to delete it) and a "cnt"
+** field that tells us its internal lock status.  cnt==0 means the
+** file is unlocked.  cnt==-1 means the file has an exclusive lock.
+** cnt>0 means there are cnt shared locks on the file.
+**
+** Any attempt to lock or unlock a file first checks the locking
+** structure.  The fcntl() system call is only invoked to set a 
+** POSIX lock if the internal lock structure transitions between
+** a locked and an unlocked state.
+**
+** But wait:  there are yet more problems with POSIX advisory locks.
+**
+** If you close a file descriptor that points to a file that has locks,
+** all locks on that file that are owned by the current process are
+** released.  To work around this problem, each unixFile structure contains
+** a pointer to an unixOpenCnt structure.  There is one unixOpenCnt structure
+** per open inode, which means that multiple unixFile can point to a single
+** unixOpenCnt.  When an attempt is made to close an unixFile, if there are
+** other unixFile open on the same inode that are holding locks, the call
+** to close() the file descriptor is deferred until all of the locks clear.
+** The unixOpenCnt structure keeps a list of file descriptors that need to
+** be closed and that list is walked (and cleared) when the last lock
+** clears.
+**
+** Yet another problem:  LinuxThreads do not play well with posix locks.
+**
+** Many older versions of linux use the LinuxThreads library which is
+** not posix compliant.  Under LinuxThreads, a lock created by thread
+** A cannot be modified or overridden by a different thread B.
+** Only thread A can modify the lock.  Locking behavior is correct
+** if the appliation uses the newer Native Posix Thread Library (NPTL)
+** on linux - with NPTL a lock created by thread A can override locks
+** in thread B.  But there is no way to know at compile-time which
+** threading library is being used.  So there is no way to know at
+** compile-time whether or not thread A can override locks on thread B.
+** We have to do a run-time check to discover the behavior of the
+** current process.
+**
+** On systems where thread A is unable to modify locks created by
+** thread B, we have to keep track of which thread created each
+** lock.  Hence there is an extra field in the key to the unixLockInfo
+** structure to record this information.  And on those systems it
+** is illegal to begin a transaction in one thread and finish it
+** in another.  For this latter restriction, there is no work-around.
+** It is a limitation of LinuxThreads.
+*/
+
+/*
+** Set or check the unixFile.tid field.  This field is set when an unixFile
+** is first opened.  All subsequent uses of the unixFile verify that the
+** same thread is operating on the unixFile.  Some operating systems do
+** not allow locks to be overridden by other threads and that restriction
+** means that sqlite3* database handles cannot be moved from one thread
+** to another while locks are held.
+**
+** Version 3.3.1 (2006-01-15):  unixFile can be moved from one thread to
+** another as long as we are running on a system that supports threads
+** overriding each others locks (which is now the most common behavior)
+** or if no locks are held.  But the unixFile.pLock field needs to be
+** recomputed because its key includes the thread-id.  See the 
+** transferOwnership() function below for additional information
+*/
+#if SQLITE_THREADSAFE && defined(__linux__)
+# define SET_THREADID(X)   (X)->tid = pthread_self()
+# define CHECK_THREADID(X) (threadsOverrideEachOthersLocks==0 && \
+                            !pthread_equal((X)->tid, pthread_self()))
+#else
+# define SET_THREADID(X)
+# define CHECK_THREADID(X) 0
+#endif
+
+/*
+** An instance of the following structure serves as the key used
+** to locate a particular unixOpenCnt structure given its inode.  This
+** is the same as the unixLockKey except that the thread ID is omitted.
+*/
+struct unixFileId {
+  dev_t dev;                  /* Device number */
+#if OS_VXWORKS
+  struct vxworksFileId *pId;  /* Unique file ID for vxworks. */
+#else
+  ino_t ino;                  /* Inode number */
+#endif
+};
+
+/*
+** An instance of the following structure serves as the key used
+** to locate a particular unixLockInfo structure given its inode.
+**
+** If threads cannot override each others locks (LinuxThreads), then we
+** set the unixLockKey.tid field to the thread ID.  If threads can override
+** each others locks (Posix and NPTL) then tid is always set to zero.
+** tid is omitted if we compile without threading support or on an OS
+** other than linux.
+*/
+struct unixLockKey {
+  struct unixFileId fid;  /* Unique identifier for the file */
+#if SQLITE_THREADSAFE && defined(__linux__)
+  pthread_t tid;  /* Thread ID of lock owner. Zero if not using LinuxThreads */
+#endif
+};
+
+/*
+** An instance of the following structure is allocated for each open
+** inode.  Or, on LinuxThreads, there is one of these structures for
+** each inode opened by each thread.
+**
+** A single inode can have multiple file descriptors, so each unixFile
+** structure contains a pointer to an instance of this object and this
+** object keeps a count of the number of unixFile pointing to it.
+*/
+struct unixLockInfo {
+  struct unixLockKey lockKey;     /* The lookup key */
+  int cnt;                        /* Number of SHARED locks held */
+  int locktype;                   /* One of SHARED_LOCK, RESERVED_LOCK etc. */
+  int nRef;                       /* Number of pointers to this structure */
+  struct unixLockInfo *pNext;     /* List of all unixLockInfo objects */
+  struct unixLockInfo *pPrev;     /*    .... doubly linked */
+};
+
+/*
+** An instance of the following structure is allocated for each open
+** inode.  This structure keeps track of the number of locks on that
+** inode.  If a close is attempted against an inode that is holding
+** locks, the close is deferred until all locks clear by adding the
+** file descriptor to be closed to the pending list.
+**
+** TODO:  Consider changing this so that there is only a single file
+** descriptor for each open file, even when it is opened multiple times.
+** The close() system call would only occur when the last database
+** using the file closes.
+*/
+struct unixOpenCnt {
+  struct unixFileId fileId;   /* The lookup key */
+  int nRef;                   /* Number of pointers to this structure */
+  int nLock;                  /* Number of outstanding locks */
+  UnixUnusedFd *pUnused;      /* Unused file descriptors to close */
+#if OS_VXWORKS
+  sem_t *pSem;                     /* Named POSIX semaphore */
+  char aSemName[MAX_PATHNAME+2];   /* Name of that semaphore */
+#endif
+  struct unixOpenCnt *pNext, *pPrev;   /* List of all unixOpenCnt objects */
+};
+
+/*
+** Lists of all unixLockInfo and unixOpenCnt objects.  These used to be hash
+** tables.  But the number of objects is rarely more than a dozen and
+** never exceeds a few thousand.  And lookup is not on a critical
+** path so a simple linked list will suffice.
+*/
+static struct unixLockInfo *lockList = 0;
+static struct unixOpenCnt *openList = 0;
+
+/*
+** This variable remembers whether or not threads can override each others
+** locks.
+**
+**    0:  No.  Threads cannot override each others locks.  (LinuxThreads)
+**    1:  Yes.  Threads can override each others locks.  (Posix & NLPT)
+**   -1:  We don't know yet.
+**
+** On some systems, we know at compile-time if threads can override each
+** others locks.  On those systems, the SQLITE_THREAD_OVERRIDE_LOCK macro
+** will be set appropriately.  On other systems, we have to check at
+** runtime.  On these latter systems, SQLTIE_THREAD_OVERRIDE_LOCK is
+** undefined.
+**
+** This variable normally has file scope only.  But during testing, we make
+** it a global so that the test code can change its value in order to verify
+** that the right stuff happens in either case.
+*/
+#if SQLITE_THREADSAFE && defined(__linux__)
+#  ifndef SQLITE_THREAD_OVERRIDE_LOCK
+#    define SQLITE_THREAD_OVERRIDE_LOCK -1
+#  endif
+#  ifdef SQLITE_TEST
+int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK;
+#  else
+static int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK;
+#  endif
+#endif
+
 /*
-** The testThreadLockingBehavior() routine launches two separate
-** threads on this routine.  This routine attempts to lock a file
-** descriptor then returns.  The success or failure of that attempt
-** allows the testThreadLockingBehavior() procedure to determine
-** whether or not threads can override each others locks.
+** This structure holds information passed into individual test
+** threads by the testThreadLockingBehavior() routine.
 */
+struct threadTestData {
+  int fd;                /* File to be locked */
+  struct flock lock;     /* The locking operation */
+  int result;            /* Result of the locking operation */
+};
+
+#if SQLITE_THREADSAFE && defined(__linux__)
+/*
+** This function is used as the main routine for a thread launched by
+** testThreadLockingBehavior(). It tests whether the shared-lock obtained
+** by the main thread in testThreadLockingBehavior() conflicts with a
+** hypothetical write-lock obtained by this thread on the same file.
+**
+** The write-lock is not actually acquired, as this is not possible if 
+** the file is open in read-only mode (see ticket #3472).
+*/ 
 static void *threadLockingTest(void *pArg){
   struct threadTestData *pData = (struct threadTestData*)pArg;
-  pData->result = fcntl(pData->fd, F_SETLK, &pData->lock);
+  pData->result = fcntl(pData->fd, F_GETLK, &pData->lock);
   return pArg;
 }
+#endif /* SQLITE_THREADSAFE && defined(__linux__) */
 
+
+#if SQLITE_THREADSAFE && defined(__linux__)
 /*
 ** This procedure attempts to determine whether or not threads
 ** can override each others locks then sets the 
@@ -19379,214 +22411,216 @@ static void *threadLockingTest(void *pArg){
 */
 static void testThreadLockingBehavior(int fd_orig){
   int fd;
-  struct threadTestData d[2];
-  pthread_t t[2];
+  int rc;
+  struct threadTestData d;
+  struct flock l;
+  pthread_t t;
 
   fd = dup(fd_orig);
   if( fd<0 ) return;
-  memset(d, 0, sizeof(d));
-  d[0].fd = fd;
-  d[0].lock.l_type = F_RDLCK;
-  d[0].lock.l_len = 1;
-  d[0].lock.l_start = 0;
-  d[0].lock.l_whence = SEEK_SET;
-  d[1] = d[0];
-  d[1].lock.l_type = F_WRLCK;
-  pthread_create(&t[0], 0, threadLockingTest, &d[0]);
-  pthread_create(&t[1], 0, threadLockingTest, &d[1]);
-  pthread_join(t[0], 0);
-  pthread_join(t[1], 0);
-  close(fd);
-  threadsOverrideEachOthersLocks =  d[0].result==0 && d[1].result==0;
-}
-#endif /* SQLITE_THREADSAFE */
-
-/*
-** Release a lockInfo structure previously allocated by findLockInfo().
-*/
-static void releaseLockInfo(struct lockInfo *pLock){
-  if (pLock == NULL)
-    return;
-  pLock->nRef--;
-  if( pLock->nRef==0 ){
-    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
-    sqlite3_free(pLock);
+  memset(&l, 0, sizeof(l));
+  l.l_type = F_RDLCK;
+  l.l_len = 1;
+  l.l_start = 0;
+  l.l_whence = SEEK_SET;
+  rc = fcntl(fd_orig, F_SETLK, &l);
+  if( rc!=0 ) return;
+  memset(&d, 0, sizeof(d));
+  d.fd = fd;
+  d.lock = l;
+  d.lock.l_type = F_WRLCK;
+  if( pthread_create(&t, 0, threadLockingTest, &d)==0 ){
+    pthread_join(t, 0);
   }
+  close(fd);
+  if( d.result!=0 ) return;
+  threadsOverrideEachOthersLocks = (d.lock.l_type==F_UNLCK);
 }
+#endif /* SQLITE_THREADSAFE && defined(__linux__) */
 
 /*
-** Release a openCnt structure previously allocated by findLockInfo().
+** Release a unixLockInfo structure previously allocated by findLockInfo().
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
 */
-static void releaseOpenCnt(struct openCnt *pOpen){
-  if (pOpen == NULL)
-    return;
-  pOpen->nRef--;
-  if( pOpen->nRef==0 ){
-    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
-    free(pOpen->aPending);
-    sqlite3_free(pOpen);
+static void releaseLockInfo(struct unixLockInfo *pLock){
+  assert( unixMutexHeld() );
+  if( pLock ){
+    pLock->nRef--;
+    if( pLock->nRef==0 ){
+      if( pLock->pPrev ){
+        assert( pLock->pPrev->pNext==pLock );
+        pLock->pPrev->pNext = pLock->pNext;
+      }else{
+        assert( lockList==pLock );
+        lockList = pLock->pNext;
+      }
+      if( pLock->pNext ){
+        assert( pLock->pNext->pPrev==pLock );
+        pLock->pNext->pPrev = pLock->pPrev;
+      }
+      sqlite3_free(pLock);
+    }
   }
 }
 
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
 /*
-** Tests a byte-range locking query to see if byte range locks are 
-** supported, if not we fall back to dotlockLockingStyle.
+** Release a unixOpenCnt structure previously allocated by findLockInfo().
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
 */
-static sqlite3LockingStyle sqlite3TestLockingStyle(
-  const char *filePath, 
-  int fd
-){
-  /* test byte-range lock using fcntl */
-  struct flock lockInfo;
-  
-  lockInfo.l_len = 1;
-  lockInfo.l_start = 0;
-  lockInfo.l_whence = SEEK_SET;
-  lockInfo.l_type = F_RDLCK;
-  
-  if( fcntl(fd, F_GETLK, &lockInfo)!=-1 ) {
-    return posixLockingStyle;
-  } 
-  
-  /* testing for flock can give false positives.  So if if the above test
-  ** fails, then we fall back to using dot-lock style locking.
-  */  
-  return dotlockLockingStyle;
-}
-
-/* 
-** Examines the f_fstypename entry in the statfs structure as returned by 
-** stat() for the file system hosting the database file, assigns the 
-** appropriate locking style based on its value.  These values and 
-** assignments are based on Darwin/OSX behavior and have not been tested on 
-** other systems.
-*/
-static sqlite3LockingStyle sqlite3DetectLockingStyle(
-  const char *filePath, 
-  int fd
-){
-
-#ifdef SQLITE_FIXED_LOCKING_STYLE
-  return (sqlite3LockingStyle)SQLITE_FIXED_LOCKING_STYLE;
-#else
-  struct statfs fsInfo;
+static void releaseOpenCnt(struct unixOpenCnt *pOpen){
+  assert( unixMutexHeld() );
+  if( pOpen ){
+    pOpen->nRef--;
+    if( pOpen->nRef==0 ){
+      if( pOpen->pPrev ){
+        assert( pOpen->pPrev->pNext==pOpen );
+        pOpen->pPrev->pNext = pOpen->pNext;
+      }else{
+        assert( openList==pOpen );
+        openList = pOpen->pNext;
+      }
+      if( pOpen->pNext ){
+        assert( pOpen->pNext->pPrev==pOpen );
+        pOpen->pNext->pPrev = pOpen->pPrev;
+      }
+#if SQLITE_THREADSAFE && defined(__linux__)
+      assert( !pOpen->pUnused || threadsOverrideEachOthersLocks==0 );
+#endif
 
-  if( statfs(filePath, &fsInfo) == -1 ){
-    return sqlite3TestLockingStyle(filePath, fd);
-  }
-  if( fsInfo.f_flags & MNT_RDONLY ){
-    return noLockingStyle;
-  }
-  if( strcmp(fsInfo.f_fstypename, "hfs")==0 ||
-      strcmp(fsInfo.f_fstypename, "ufs")==0 ){
-    return posixLockingStyle;
-  }
-  if( strcmp(fsInfo.f_fstypename, "afpfs")==0 ){
-    return afpLockingStyle;
-  }
-  if( strcmp(fsInfo.f_fstypename, "nfs")==0 ){
-    return sqlite3TestLockingStyle(filePath, fd);
-  }
-  if( strcmp(fsInfo.f_fstypename, "smbfs")==0 ){
-    return flockLockingStyle;
-  }
-  if( strcmp(fsInfo.f_fstypename, "msdos")==0 ){
-    return dotlockLockingStyle;
-  }
-  if( strcmp(fsInfo.f_fstypename, "webdav")==0 ){
-    return unsupportedLockingStyle;
+      /* If pOpen->pUnused is not null, then memory and file-descriptors
+      ** are leaked.
+      **
+      ** This will only happen if, under Linuxthreads, the user has opened
+      ** a transaction in one thread, then attempts to close the database
+      ** handle from another thread (without first unlocking the db file).
+      ** This is a misuse.  */
+      sqlite3_free(pOpen);
+    }
   }
-  return sqlite3TestLockingStyle(filePath, fd);  
-#endif /* SQLITE_FIXED_LOCKING_STYLE */
 }
 
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
-
 /*
-** Given a file descriptor, locate lockInfo and openCnt structures that
+** Given a file descriptor, locate unixLockInfo and unixOpenCnt structures that
 ** describes that file descriptor.  Create new ones if necessary.  The
 ** return values might be uninitialized if an error occurs.
 **
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
+**
 ** Return an appropriate error code.
 */
 static int findLockInfo(
-  int fd,                      /* The file descriptor used in the key */
-  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
-  struct openCnt **ppOpen      /* Return the openCnt structure here */
+  unixFile *pFile,               /* Unix file with file desc used in the key */
+  struct unixLockInfo **ppLock,  /* Return the unixLockInfo structure here */
+  struct unixOpenCnt **ppOpen    /* Return the unixOpenCnt structure here */
 ){
-  int rc;
-  struct lockKey key1;
-  struct openKey key2;
-  struct stat statbuf;
-  struct lockInfo *pLock;
-  struct openCnt *pOpen;
+  int rc;                        /* System call return code */
+  int fd;                        /* The file descriptor for pFile */
+  struct unixLockKey lockKey;    /* Lookup key for the unixLockInfo structure */
+  struct unixFileId fileId;      /* Lookup key for the unixOpenCnt struct */
+  struct stat statbuf;           /* Low-level file information */
+  struct unixLockInfo *pLock = 0;/* Candidate unixLockInfo object */
+  struct unixOpenCnt *pOpen;     /* Candidate unixOpenCnt object */
+
+  assert( unixMutexHeld() );
+
+  /* Get low-level information about the file that we can used to
+  ** create a unique name for the file.
+  */
+  fd = pFile->h;
   rc = fstat(fd, &statbuf);
   if( rc!=0 ){
+    pFile->lastErrno = errno;
 #ifdef EOVERFLOW
-    if( errno==EOVERFLOW ) return SQLITE_NOLFS;
+    if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
 #endif
     return SQLITE_IOERR;
   }
 
-  memset(&key1, 0, sizeof(key1));
-  key1.dev = statbuf.st_dev;
-  key1.ino = statbuf.st_ino;
-#if SQLITE_THREADSAFE
+#ifdef __APPLE__
+  /* On OS X on an msdos filesystem, the inode number is reported
+  ** incorrectly for zero-size files.  See ticket #3260.  To work
+  ** around this problem (we consider it a bug in OS X, not SQLite)
+  ** we always increase the file size to 1 by writing a single byte
+  ** prior to accessing the inode number.  The one byte written is
+  ** an ASCII 'S' character which also happens to be the first byte
+  ** in the header of every SQLite database.  In this way, if there
+  ** is a race condition such that another thread has already populated
+  ** the first page of the database, no damage is done.
+  */
+  if( statbuf.st_size==0 ){
+    rc = write(fd, "S", 1);
+    if( rc!=1 ){
+      return SQLITE_IOERR;
+    }
+    rc = fstat(fd, &statbuf);
+    if( rc!=0 ){
+      pFile->lastErrno = errno;
+      return SQLITE_IOERR;
+    }
+  }
+#endif
+
+  memset(&lockKey, 0, sizeof(lockKey));
+  lockKey.fid.dev = statbuf.st_dev;
+#if OS_VXWORKS
+  lockKey.fid.pId = pFile->pId;
+#else
+  lockKey.fid.ino = statbuf.st_ino;
+#endif
+#if SQLITE_THREADSAFE && defined(__linux__)
   if( threadsOverrideEachOthersLocks<0 ){
     testThreadLockingBehavior(fd);
   }
-  key1.tid = threadsOverrideEachOthersLocks ? 0 : pthread_self();
+  lockKey.tid = threadsOverrideEachOthersLocks ? 0 : pthread_self();
 #endif
-  memset(&key2, 0, sizeof(key2));
-  key2.dev = statbuf.st_dev;
-  key2.ino = statbuf.st_ino;
-  pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1));
-  if( pLock==0 ){
-    struct lockInfo *pOld;
-    pLock = sqlite3_malloc( sizeof(*pLock) );
+  fileId = lockKey.fid;
+  if( ppLock!=0 ){
+    pLock = lockList;
+    while( pLock && memcmp(&lockKey, &pLock->lockKey, sizeof(lockKey)) ){
+      pLock = pLock->pNext;
+    }
     if( pLock==0 ){
-      rc = SQLITE_NOMEM;
-      goto exit_findlockinfo;
-    }
-    pLock->key = key1;
-    pLock->nRef = 1;
-    pLock->cnt = 0;
-    pLock->locktype = 0;
-    pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock);
-    if( pOld!=0 ){
-      assert( pOld==pLock );
-      sqlite3_free(pLock);
-      rc = SQLITE_NOMEM;
-      goto exit_findlockinfo;
+      pLock = sqlite3_malloc( sizeof(*pLock) );
+      if( pLock==0 ){
+        rc = SQLITE_NOMEM;
+        goto exit_findlockinfo;
+      }
+      memcpy(&pLock->lockKey,&lockKey,sizeof(lockKey));
+      pLock->nRef = 1;
+      pLock->cnt = 0;
+      pLock->locktype = 0;
+      pLock->pNext = lockList;
+      pLock->pPrev = 0;
+      if( lockList ) lockList->pPrev = pLock;
+      lockList = pLock;
+    }else{
+      pLock->nRef++;
     }
-  }else{
-    pLock->nRef++;
+    *ppLock = pLock;
   }
-  *ppLock = pLock;
   if( ppOpen!=0 ){
-    pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
+    pOpen = openList;
+    while( pOpen && memcmp(&fileId, &pOpen->fileId, sizeof(fileId)) ){
+      pOpen = pOpen->pNext;
+    }
     if( pOpen==0 ){
-      struct openCnt *pOld;
       pOpen = sqlite3_malloc( sizeof(*pOpen) );
       if( pOpen==0 ){
         releaseLockInfo(pLock);
         rc = SQLITE_NOMEM;
         goto exit_findlockinfo;
       }
-      pOpen->key = key2;
+      memset(pOpen, 0, sizeof(*pOpen));
+      pOpen->fileId = fileId;
       pOpen->nRef = 1;
-      pOpen->nLock = 0;
-      pOpen->nPending = 0;
-      pOpen->aPending = 0;
-      pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
-      if( pOld!=0 ){
-        assert( pOld==pOpen );
-        sqlite3_free(pOpen);
-        releaseLockInfo(pLock);
-        rc = SQLITE_NOMEM;
-        goto exit_findlockinfo;
-      }
+      pOpen->pNext = openList;
+      if( openList ) openList->pPrev = pOpen;
+      openList = pOpen;
     }else{
       pOpen->nRef++;
     }
@@ -19597,38 +22631,18 @@ exit_findlockinfo:
   return rc;
 }
 
-#ifdef SQLITE_DEBUG
-/*
-** Helper function for printing out trace information from debugging
-** binaries. This returns the string represetation of the supplied
-** integer lock-type.
-*/
-static const char *locktypeName(int locktype){
-  switch( locktype ){
-  case NO_LOCK: return "NONE";
-  case SHARED_LOCK: return "SHARED";
-  case RESERVED_LOCK: return "RESERVED";
-  case PENDING_LOCK: return "PENDING";
-  case EXCLUSIVE_LOCK: return "EXCLUSIVE";
-  }
-  return "ERROR";
-}
-#endif
-
 /*
 ** If we are currently in a different thread than the thread that the
 ** unixFile argument belongs to, then transfer ownership of the unixFile
 ** over to the current thread.
 **
-** A unixFile is only owned by a thread on systems where one thread is
-** unable to override locks created by a different thread.  RedHat9 is
-** an example of such a system.
+** A unixFile is only owned by a thread on systems that use LinuxThreads.
 **
 ** Ownership transfer is only allowed if the unixFile is currently unlocked.
 ** If the unixFile is locked and an ownership is wrong, then return
 ** SQLITE_MISUSE.  SQLITE_OK is returned if everything works.
 */
-#if SQLITE_THREADSAFE
+#if SQLITE_THREADSAFE && defined(__linux__)
 static int transferOwnership(unixFile *pFile){
   int rc;
   pthread_t hSelf;
@@ -19651,7 +22665,7 @@ static int transferOwnership(unixFile *pFile){
   pFile->tid = hSelf;
   if (pFile->pLock != NULL) {
     releaseLockInfo(pFile->pLock);
-    rc = findLockInfo(pFile->h, &pFile->pLock, 0);
+    rc = findLockInfo(pFile, &pFile->pLock, 0);
     OSTRACE5("LOCK    %d is now %s(%s,%d)\n", pFile->h,
            locktypeName(pFile->locktype),
            locktypeName(pFile->pLock->locktype), pFile->pLock->cnt);
@@ -19660,349 +22674,123 @@ static int transferOwnership(unixFile *pFile){
     return SQLITE_OK;
   }
 }
-#else
+#else  /* if not SQLITE_THREADSAFE */
   /* On single-threaded builds, ownership transfer is a no-op */
 # define transferOwnership(X) SQLITE_OK
-#endif
+#endif /* SQLITE_THREADSAFE */
 
-/*
-** Seek to the offset passed as the second argument, then read cnt 
-** bytes into pBuf. Return the number of bytes actually read.
-**
-** NB:  If you define USE_PREAD or USE_PREAD64, then it might also
-** be necessary to define _XOPEN_SOURCE to be 500.  This varies from
-** one system to another.  Since SQLite does not define USE_PREAD
-** any any form by default, we will not attempt to define _XOPEN_SOURCE.
-** See tickets #2741 and #2681.
-*/
-static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
-  int got;
-  i64 newOffset;
-  TIMER_START;
-#if defined(USE_PREAD)
-  got = pread(id->h, pBuf, cnt, offset);
-  SimulateIOError( got = -1 );
-#elif defined(USE_PREAD64)
-  got = pread64(id->h, pBuf, cnt, offset);
-  SimulateIOError( got = -1 );
-#else
-  newOffset = lseek(id->h, offset, SEEK_SET);
-  SimulateIOError( newOffset-- );
-  if( newOffset!=offset ){
-    return -1;
-  }
-  got = read(id->h, pBuf, cnt);
-#endif
-  TIMER_END;
-  OSTRACE5("READ    %-3d %5d %7lld %d\n", id->h, got, offset, TIMER_ELAPSED);
-  return got;
-}
 
 /*
-** Read data from a file into a buffer.  Return SQLITE_OK if all
-** bytes were read successfully and SQLITE_IOERR if anything goes
-** wrong.
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
 */
-static int unixRead(
-  sqlite3_file *id, 
-  void *pBuf, 
-  int amt,
-  sqlite3_int64 offset
-){
-  int got;
-  assert( id );
-  got = seekAndRead((unixFile*)id, offset, pBuf, amt);
-  if( got==amt ){
-    return SQLITE_OK;
-  }else if( got<0 ){
-    return SQLITE_IOERR_READ;
-  }else{
-    memset(&((char*)pBuf)[got], 0, amt-got);
-    return SQLITE_IOERR_SHORT_READ;
-  }
-}
+static int unixCheckReservedLock(sqlite3_file *id, int *pResOut){
+  int rc = SQLITE_OK;
+  int reserved = 0;
+  unixFile *pFile = (unixFile*)id;
 
-/*
-** Seek to the offset in id->offset then read cnt bytes into pBuf.
-** Return the number of bytes actually read.  Update the offset.
-*/
-static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
-  int got;
-  i64 newOffset;
-  TIMER_START;
-#if defined(USE_PREAD)
-  got = pwrite(id->h, pBuf, cnt, offset);
-#elif defined(USE_PREAD64)
-  got = pwrite64(id->h, pBuf, cnt, offset);
-#else
-  newOffset = lseek(id->h, offset, SEEK_SET);
-  if( newOffset!=offset ){
-    return -1;
-  }
-# ifndef VXWORKS
-  got = write(id->h, pBuf, cnt);
-# else
-  got = write(id->h, (char *)pBuf, cnt);
-# endif
-#endif
-  TIMER_END;
-  OSTRACE5("WRITE   %-3d %5d %7lld %d\n", id->h, got, offset, TIMER_ELAPSED);
-  return got;
-}
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
 
+  assert( pFile );
+  unixEnterMutex(); /* Because pFile->pLock is shared across threads */
 
-/*
-** Write data from a buffer into a file.  Return SQLITE_OK on success
-** or some other error code on failure.
-*/
-static int unixWrite(
-  sqlite3_file *id, 
-  const void *pBuf, 
-  int amt,
-  sqlite3_int64 offset 
-){
-  int wrote = 0;
-  assert( id );
-  assert( amt>0 );
-  while( amt>0 && (wrote = seekAndWrite((unixFile*)id, offset, pBuf, amt))>0 ){
-    amt -= wrote;
-    offset += wrote;
-    pBuf = &((char*)pBuf)[wrote];
+  /* Check if a thread in this process holds such a lock */
+  if( pFile->pLock->locktype>SHARED_LOCK ){
+    reserved = 1;
   }
-  SimulateIOError(( wrote=(-1), amt=1 ));
-  SimulateDiskfullError(( wrote=0, amt=1 ));
-  if( amt>0 ){
-    if( wrote<0 ){
-      return SQLITE_IOERR_WRITE;
-    }else{
-      return SQLITE_FULL;
+
+  /* Otherwise see if some other process holds it.
+  */
+#ifndef __DJGPP__
+  if( !reserved ){
+    struct flock lock;
+    lock.l_whence = SEEK_SET;
+    lock.l_start = RESERVED_BYTE;
+    lock.l_len = 1;
+    lock.l_type = F_WRLCK;
+    if (-1 == fcntl(pFile->h, F_GETLK, &lock)) {
+      int tErrno = errno;
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
+      pFile->lastErrno = tErrno;
+    } else if( lock.l_type!=F_UNLCK ){
+      reserved = 1;
     }
   }
-  return SQLITE_OK;
-}
-
-#ifdef SQLITE_TEST
-/*
-** Count the number of fullsyncs and normal syncs.  This is used to test
-** that syncs and fullsyncs are occuring at the right times.
-*/
-SQLITE_API int sqlite3_sync_count = 0;
-SQLITE_API int sqlite3_fullsync_count = 0;
-#endif
-
-/*
-** Use the fdatasync() API only if the HAVE_FDATASYNC macro is defined.
-** Otherwise use fsync() in its place.
-*/
-#ifndef HAVE_FDATASYNC
-# define fdatasync fsync
-#endif
-
-/*
-** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not
-** the F_FULLFSYNC macro is defined.  F_FULLFSYNC is currently
-** only available on Mac OS X.  But that could change.
-*/
-#ifdef F_FULLFSYNC
-# define HAVE_FULLFSYNC 1
-#else
-# define HAVE_FULLFSYNC 0
 #endif
+  
+  unixLeaveMutex();
+  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);
 
+  *pResOut = reserved;
+  return rc;
+}
 
 /*
-** The fsync() system call does not work as advertised on many
-** unix systems.  The following procedure is an attempt to make
-** it work better.
+** Perform a file locking operation on a range of bytes in a file.
+** The "op" parameter should be one of F_RDLCK, F_WRLCK, or F_UNLCK.
+** Return 0 on success or -1 for failure.  On failure, write the error
+** code into *pErrcode.
 **
-** The SQLITE_NO_SYNC macro disables all fsync()s.  This is useful
-** for testing when we want to run through the test suite quickly.
-** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
-** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
-** or power failure will likely corrupt the database file.
+** If the SQLITE_WHOLE_FILE_LOCKING bit is clear, then only lock
+** the range of bytes on the locking page between SHARED_FIRST and
+** SHARED_SIZE.  If SQLITE_WHOLE_FILE_LOCKING is set, then lock all
+** bytes from 0 up to but not including PENDING_BYTE, and all bytes
+** that follow SHARED_FIRST.
+**
+** In other words, of SQLITE_WHOLE_FILE_LOCKING if false (the historical
+** default case) then only lock a small range of bytes from SHARED_FIRST
+** through SHARED_FIRST+SHARED_SIZE-1.  But if SQLITE_WHOLE_FILE_LOCKING is
+** true then lock every byte in the file except for PENDING_BYTE and
+** RESERVED_BYTE.
+**
+** SQLITE_WHOLE_FILE_LOCKING=true overlaps SQLITE_WHOLE_FILE_LOCKING=false
+** and so the locking schemes are compatible.  One type of lock will
+** effectively exclude the other type.  The reason for using the
+** SQLITE_WHOLE_FILE_LOCKING=true is that by indicating the full range
+** of bytes to be read or written, we give hints to NFS to help it
+** maintain cache coherency.  On the other hand, whole file locking
+** is slower, so we don't want to use it except for NFS.
 */
-static int full_fsync(int fd, int fullSync, int dataOnly){
+static int rangeLock(unixFile *pFile, int op, int *pErrcode){
+  struct flock lock;
   int rc;
-
-  /* Record the number of times that we do a normal fsync() and 
-  ** FULLSYNC.  This is used during testing to verify that this procedure
-  ** gets called with the correct arguments.
-  */
-#ifdef SQLITE_TEST
-  if( fullSync ) sqlite3_fullsync_count++;
-  sqlite3_sync_count++;
-#endif
-
-  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
-  ** no-op
-  */
-#ifdef SQLITE_NO_SYNC
-  rc = SQLITE_OK;
-#else
-
-#if HAVE_FULLFSYNC
-  if( fullSync ){
-    rc = fcntl(fd, F_FULLFSYNC, 0);
-  }else{
-    rc = 1;
-  }
-  /* If the FULLFSYNC failed, fall back to attempting an fsync().
-   * It shouldn't be possible for fullfsync to fail on the local 
-   * file system (on OSX), so failure indicates that FULLFSYNC
-   * isn't supported for this file system. So, attempt an fsync 
-   * and (for now) ignore the overhead of a superfluous fcntl call.  
-   * It'd be better to detect fullfsync support once and avoid 
-   * the fcntl call every time sync is called.
-   */
-  if( rc ) rc = fsync(fd);
-
-#else 
-  if( dataOnly ){
-    rc = fdatasync(fd);
+  lock.l_type = op;
+  lock.l_start = SHARED_FIRST;
+  lock.l_whence = SEEK_SET;
+  if( (pFile->fileFlags & SQLITE_WHOLE_FILE_LOCKING)==0 ){
+    lock.l_len = SHARED_SIZE;
+    rc = fcntl(pFile->h, F_SETLK, &lock);
+    *pErrcode = errno;
   }else{
-    rc = fsync(fd);
+    lock.l_len = 0;
+    rc = fcntl(pFile->h, F_SETLK, &lock);
+    *pErrcode = errno;
+    if( NEVER(op==F_UNLCK) || rc!=(-1) ){
+      lock.l_start = 0;
+      lock.l_len = PENDING_BYTE;
+      rc = fcntl(pFile->h, F_SETLK, &lock);
+      if( ALWAYS(op!=F_UNLCK) && rc==(-1) ){
+        *pErrcode = errno;
+        lock.l_type = F_UNLCK;
+        lock.l_start = SHARED_FIRST;
+        lock.l_len = 0;
+        fcntl(pFile->h, F_SETLK, &lock);
+      }
+    }
   }
-#endif /* HAVE_FULLFSYNC */
-#endif /* defined(SQLITE_NO_SYNC) */
-
   return rc;
 }
 
 /*
-** Make sure all writes to a particular file are committed to disk.
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
 **
-** If dataOnly==0 then both the file itself and its metadata (file
-** size, access time, etc) are synced.  If dataOnly!=0 then only the
-** file data is synced.
-**
-** Under Unix, also make sure that the directory entry for the file
-** has been created by fsync-ing the directory that contains the file.
-** If we do not do this and we encounter a power failure, the directory
-** entry for the journal might not exist after we reboot.  The next
-** SQLite to access the file will not know that the journal exists (because
-** the directory entry for the journal was never created) and the transaction
-** will not roll back - possibly leading to database corruption.
-*/
-static int unixSync(sqlite3_file *id, int flags){
-  int rc;
-  unixFile *pFile = (unixFile*)id;
-
-  int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
-  int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;
-
-  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
-  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
-      || (flags&0x0F)==SQLITE_SYNC_FULL
-  );
-
-  assert( pFile );
-  OSTRACE2("SYNC    %-3d\n", pFile->h);
-  rc = full_fsync(pFile->h, isFullsync, isDataOnly);
-  SimulateIOError( rc=1 );
-  if( rc ){
-    return SQLITE_IOERR_FSYNC;
-  }
-  if( pFile->dirfd>=0 ){
-    OSTRACE4("DIRSYNC %-3d (have_fullfsync=%d fullsync=%d)\n", pFile->dirfd,
-            HAVE_FULLFSYNC, isFullsync);
-#ifndef SQLITE_DISABLE_DIRSYNC
-    /* The directory sync is only attempted if full_fsync is
-    ** turned off or unavailable.  If a full_fsync occurred above,
-    ** then the directory sync is superfluous.
-    */
-    if( (!HAVE_FULLFSYNC || !isFullsync) && full_fsync(pFile->dirfd,0,0) ){
-       /*
-       ** We have received multiple reports of fsync() returning
-       ** errors when applied to directories on certain file systems.
-       ** A failed directory sync is not a big deal.  So it seems
-       ** better to ignore the error.  Ticket #1657
-       */
-       /* return SQLITE_IOERR; */
-    }
-#endif
-    close(pFile->dirfd);  /* Only need to sync once, so close the directory */
-    pFile->dirfd = -1;    /* when we are done. */
-  }
-  return SQLITE_OK;
-}
-
-/*
-** Truncate an open file to a specified size
-*/
-static int unixTruncate(sqlite3_file *id, i64 nByte){
-  int rc;
-  assert( id );
-  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
-  rc = ftruncate(((unixFile*)id)->h, (off_t)nByte);
-  if( rc ){
-    return SQLITE_IOERR_TRUNCATE;
-  }else{
-    return SQLITE_OK;
-  }
-}
-
-/*
-** Determine the current size of a file in bytes
-*/
-static int unixFileSize(sqlite3_file *id, i64 *pSize){
-  int rc;
-  struct stat buf;
-  assert( id );
-  rc = fstat(((unixFile*)id)->h, &buf);
-  SimulateIOError( rc=1 );
-  if( rc!=0 ){
-    return SQLITE_IOERR_FSTAT;
-  }
-  *pSize = buf.st_size;
-  return SQLITE_OK;
-}
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, return
-** non-zero.  If the file is unlocked or holds only SHARED locks, then
-** return zero.
-*/
-static int unixCheckReservedLock(sqlite3_file *id){
-  int r = 0;
-  unixFile *pFile = (unixFile*)id;
-
-  assert( pFile );
-  enterMutex(); /* Because pFile->pLock is shared across threads */
-
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->pLock->locktype>SHARED_LOCK ){
-    r = 1;
-  }
-
-  /* Otherwise see if some other process holds it.
-  */
-  if( !r ){
-    struct flock lock;
-    lock.l_whence = SEEK_SET;
-    lock.l_start = RESERVED_BYTE;
-    lock.l_len = 1;
-    lock.l_type = F_WRLCK;
-    fcntl(pFile->h, F_GETLK, &lock);
-    if( lock.l_type!=F_UNLCK ){
-      r = 1;
-    }
-  }
-  
-  leaveMutex();
-  OSTRACE3("TEST WR-LOCK %d %d\n", pFile->h, r);
-
-  return r;
-}
-
-/*
-** Lock the file with the lock specified by parameter locktype - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
 **
 ** Sometimes when requesting one lock state, additional lock states
 ** are inserted in between.  The locking might fail on one of the later
@@ -20060,9 +22848,10 @@ static int unixLock(sqlite3_file *id, int locktype){
   */
   int rc = SQLITE_OK;
   unixFile *pFile = (unixFile*)id;
-  struct lockInfo *pLock = pFile->pLock;
+  struct unixLockInfo *pLock = pFile->pLock;
   struct flock lock;
-  int s;
+  int s = 0;
+  int tErrno;
 
   assert( pFile );
   OSTRACE7("LOCK    %d %s was %s(%s,%d) pid=%d\n", pFile->h,
@@ -20071,7 +22860,7 @@ static int unixLock(sqlite3_file *id, int locktype){
 
   /* If there is already a lock of this type or more restrictive on the
   ** unixFile, do nothing. Don't use the end_lock: exit path, as
-  ** enterMutex() hasn't been called yet.
+  ** unixEnterMutex() hasn't been called yet.
   */
   if( pFile->locktype>=locktype ){
     OSTRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
@@ -20079,7 +22868,10 @@ static int unixLock(sqlite3_file *id, int locktype){
     return SQLITE_OK;
   }
 
-  /* Make sure the locking sequence is correct
+  /* Make sure the locking sequence is correct.
+  **  (1) We never move from unlocked to anything higher than shared lock.
+  **  (2) SQLite never explicitly requests a pendig lock.
+  **  (3) A shared lock is always held when a reserve lock is requested.
   */
   assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
   assert( locktype!=PENDING_LOCK );
@@ -20087,13 +22879,13 @@ static int unixLock(sqlite3_file *id, int locktype){
 
   /* This mutex is needed because pFile->pLock is shared across threads
   */
-  enterMutex();
+  unixEnterMutex();
 
   /* Make sure the current thread owns the pFile.
   */
   rc = transferOwnership(pFile);
   if( rc!=SQLITE_OK ){
-    leaveMutex();
+    unixLeaveMutex();
     return rc;
   }
   pLock = pFile->pLock;
@@ -20123,14 +22915,13 @@ static int unixLock(sqlite3_file *id, int locktype){
     goto end_lock;
   }
 
-  lock.l_len = 1L;
-
-  lock.l_whence = SEEK_SET;
 
   /* A PENDING lock is needed before acquiring a SHARED lock and before
   ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
   ** be released.
   */
+  lock.l_len = 1L;
+  lock.l_whence = SEEK_SET;
   if( locktype==SHARED_LOCK 
       || (locktype==EXCLUSIVE_LOCK && pFile->locktype<PENDING_LOCK)
   ){
@@ -20138,7 +22929,11 @@ static int unixLock(sqlite3_file *id, int locktype){
     lock.l_start = PENDING_BYTE;
     s = fcntl(pFile->h, F_SETLK, &lock);
     if( s==(-1) ){
-      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
+      tErrno = errno;
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+      if( IS_LOCK_ERROR(rc) ){
+        pFile->lastErrno = tErrno;
+      }
       goto end_lock;
     }
   }
@@ -20152,20 +22947,28 @@ static int unixLock(sqlite3_file *id, int locktype){
     assert( pLock->locktype==0 );
 
     /* Now get the read-lock */
-    lock.l_start = SHARED_FIRST;
-    lock.l_len = SHARED_SIZE;
-    s = fcntl(pFile->h, F_SETLK, &lock);
+    s = rangeLock(pFile, F_RDLCK, &tErrno);
 
     /* Drop the temporary PENDING lock */
     lock.l_start = PENDING_BYTE;
     lock.l_len = 1L;
     lock.l_type = F_UNLCK;
     if( fcntl(pFile->h, F_SETLK, &lock)!=0 ){
-      rc = SQLITE_IOERR_UNLOCK;  /* This should never happen */
-      goto end_lock;
+      if( s != -1 ){
+        /* This could happen with a network mount */
+        tErrno = errno; 
+        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK); 
+        if( IS_LOCK_ERROR(rc) ){
+          pFile->lastErrno = tErrno;
+        }
+        goto end_lock;
+      }
     }
     if( s==(-1) ){
-      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+      if( IS_LOCK_ERROR(rc) ){
+        pFile->lastErrno = tErrno;
+      }
     }else{
       pFile->locktype = SHARED_LOCK;
       pFile->pOpen->nLock++;
@@ -20185,20 +22988,41 @@ static int unixLock(sqlite3_file *id, int locktype){
     switch( locktype ){
       case RESERVED_LOCK:
         lock.l_start = RESERVED_BYTE;
+        s = fcntl(pFile->h, F_SETLK, &lock);
+        tErrno = errno;
         break;
       case EXCLUSIVE_LOCK:
-        lock.l_start = SHARED_FIRST;
-        lock.l_len = SHARED_SIZE;
+        s = rangeLock(pFile, F_WRLCK, &tErrno);
         break;
       default:
         assert(0);
     }
-    s = fcntl(pFile->h, F_SETLK, &lock);
     if( s==(-1) ){
-      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+      if( IS_LOCK_ERROR(rc) ){
+        pFile->lastErrno = tErrno;
+      }
     }
   }
   
+
+#ifndef NDEBUG
+  /* Set up the transaction-counter change checking flags when
+  ** transitioning from a SHARED to a RESERVED lock.  The change
+  ** from SHARED to RESERVED marks the beginning of a normal
+  ** write operation (not a hot journal rollback).
+  */
+  if( rc==SQLITE_OK
+   && pFile->locktype<=SHARED_LOCK
+   && locktype==RESERVED_LOCK
+  ){
+    pFile->transCntrChng = 0;
+    pFile->dbUpdate = 0;
+    pFile->inNormalWrite = 1;
+  }
+#endif
+
+
   if( rc==SQLITE_OK ){
     pFile->locktype = locktype;
     pLock->locktype = locktype;
@@ -20208,13 +23032,56 @@ static int unixLock(sqlite3_file *id, int locktype){
   }
 
 end_lock:
-  leaveMutex();
+  unixLeaveMutex();
   OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
       rc==SQLITE_OK ? "ok" : "failed");
   return rc;
 }
 
 /*
+** Close all file descriptors accumuated in the unixOpenCnt->pUnused list.
+** If all such file descriptors are closed without error, the list is
+** cleared and SQLITE_OK returned.
+**
+** Otherwise, if an error occurs, then successfully closed file descriptor
+** entries are removed from the list, and SQLITE_IOERR_CLOSE returned. 
+** not deleted and SQLITE_IOERR_CLOSE returned.
+*/ 
+static int closePendingFds(unixFile *pFile){
+  int rc = SQLITE_OK;
+  struct unixOpenCnt *pOpen = pFile->pOpen;
+  UnixUnusedFd *pError = 0;
+  UnixUnusedFd *p;
+  UnixUnusedFd *pNext;
+  for(p=pOpen->pUnused; p; p=pNext){
+    pNext = p->pNext;
+    if( close(p->fd) ){
+      pFile->lastErrno = errno;
+      rc = SQLITE_IOERR_CLOSE;
+      p->pNext = pError;
+      pError = p;
+    }else{
+      sqlite3_free(p);
+    }
+  }
+  pOpen->pUnused = pError;
+  return rc;
+}
+
+/*
+** Add the file descriptor used by file handle pFile to the corresponding
+** pUnused list.
+*/
+static void setPendingFd(unixFile *pFile){
+  struct unixOpenCnt *pOpen = pFile->pOpen;
+  UnixUnusedFd *p = pFile->pUnused;
+  p->pNext = pOpen->pUnused;
+  pOpen->pUnused = p;
+  pFile->h = -1;
+  pFile->pUnused = 0;
+}
+
+/*
 ** Lower the locking level on file descriptor pFile to locktype.  locktype
 ** must be either NO_LOCK or SHARED_LOCK.
 **
@@ -20222,11 +23089,12 @@ end_lock:
 ** the requested locking level, this routine is a no-op.
 */
 static int unixUnlock(sqlite3_file *id, int locktype){
-  struct lockInfo *pLock;
-  struct flock lock;
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile*)id;
-  int h;
+  unixFile *pFile = (unixFile*)id; /* The open file */
+  struct unixLockInfo *pLock;      /* Structure describing current lock state */
+  struct flock lock;               /* Information passed into fcntl() */
+  int rc = SQLITE_OK;              /* Return code from this interface */
+  int h;                           /* The underlying file descriptor */
+  int tErrno;                      /* Error code from system call errors */
 
   assert( pFile );
   OSTRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", pFile->h, locktype,
@@ -20239,7 +23107,7 @@ static int unixUnlock(sqlite3_file *id, int locktype){
   if( CHECK_THREADID(pFile) ){
     return SQLITE_MISUSE;
   }
-  enterMutex();
+  unixEnterMutex();
   h = pFile->h;
   pLock = pFile->pLock;
   assert( pLock->cnt!=0 );
@@ -20248,13 +23116,30 @@ static int unixUnlock(sqlite3_file *id, int locktype){
     SimulateIOErrorBenign(1);
     SimulateIOError( h=(-1) )
     SimulateIOErrorBenign(0);
+
+#ifndef NDEBUG
+    /* When reducing a lock such that other processes can start
+    ** reading the database file again, make sure that the
+    ** transaction counter was updated if any part of the database
+    ** file changed.  If the transaction counter is not updated,
+    ** other connections to the same file might not realize that
+    ** the file has changed and hence might not know to flush their
+    ** cache.  The use of a stale cache can lead to database corruption.
+    */
+    assert( pFile->inNormalWrite==0
+         || pFile->dbUpdate==0
+         || pFile->transCntrChng==1 );
+    pFile->inNormalWrite = 0;
+#endif
+
+
     if( locktype==SHARED_LOCK ){
-      lock.l_type = F_RDLCK;
-      lock.l_whence = SEEK_SET;
-      lock.l_start = SHARED_FIRST;
-      lock.l_len = SHARED_SIZE;
-      if( fcntl(h, F_SETLK, &lock)==(-1) ){
-        rc = SQLITE_IOERR_RDLOCK;
+      if( rangeLock(pFile, F_RDLCK, &tErrno)==(-1) ){
+        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
+        if( IS_LOCK_ERROR(rc) ){
+          pFile->lastErrno = tErrno;
+        }
+        goto end_unlock;
       }
     }
     lock.l_type = F_UNLCK;
@@ -20264,11 +23149,16 @@ static int unixUnlock(sqlite3_file *id, int locktype){
     if( fcntl(h, F_SETLK, &lock)!=(-1) ){
       pLock->locktype = SHARED_LOCK;
     }else{
-      rc = SQLITE_IOERR_UNLOCK;
+      tErrno = errno;
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+      if( IS_LOCK_ERROR(rc) ){
+        pFile->lastErrno = tErrno;
+      }
+      goto end_unlock;
     }
   }
   if( locktype==NO_LOCK ){
-    struct openCnt *pOpen;
+    struct unixOpenCnt *pOpen;
 
     /* Decrement the shared lock counter.  Release the lock using an
     ** OS call only when all threads in this same process have released
@@ -20285,8 +23175,13 @@ static int unixUnlock(sqlite3_file *id, int locktype){
       if( fcntl(h, F_SETLK, &lock)!=(-1) ){
         pLock->locktype = NO_LOCK;
       }else{
-        rc = SQLITE_IOERR_UNLOCK;
-        pLock->cnt = 1;
+        tErrno = errno;
+        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+        if( IS_LOCK_ERROR(rc) ){
+          pFile->lastErrno = tErrno;
+        }
+        pLock->locktype = NO_LOCK;
+        pFile->locktype = NO_LOCK;
       }
     }
 
@@ -20294,288 +23189,268 @@ static int unixUnlock(sqlite3_file *id, int locktype){
     ** count reaches zero, close any other file descriptors whose close
     ** was deferred because of outstanding locks.
     */
-    if( rc==SQLITE_OK ){
-      pOpen = pFile->pOpen;
-      pOpen->nLock--;
-      assert( pOpen->nLock>=0 );
-      if( pOpen->nLock==0 && pOpen->nPending>0 ){
-        int i;
-        for(i=0; i<pOpen->nPending; i++){
-          close(pOpen->aPending[i]);
-        }
-        free(pOpen->aPending);
-        pOpen->nPending = 0;
-        pOpen->aPending = 0;
+    pOpen = pFile->pOpen;
+    pOpen->nLock--;
+    assert( pOpen->nLock>=0 );
+    if( pOpen->nLock==0 ){
+      int rc2 = closePendingFds(pFile);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
       }
     }
   }
-  leaveMutex();
+	
+end_unlock:
+  unixLeaveMutex();
   if( rc==SQLITE_OK ) pFile->locktype = locktype;
   return rc;
 }
 
 /*
+** This function performs the parts of the "close file" operation 
+** common to all locking schemes. It closes the directory and file
+** handles, if they are valid, and sets all fields of the unixFile
+** structure to 0.
+**
+** It is *not* necessary to hold the mutex when this routine is called,
+** even on VxWorks.  A mutex will be acquired on VxWorks by the
+** vxworksReleaseFileId() routine.
+*/
+static int closeUnixFile(sqlite3_file *id){
+  unixFile *pFile = (unixFile*)id;
+  if( pFile ){
+    if( pFile->dirfd>=0 ){
+      int err = close(pFile->dirfd);
+      if( err ){
+        pFile->lastErrno = errno;
+        return SQLITE_IOERR_DIR_CLOSE;
+      }else{
+        pFile->dirfd=-1;
+      }
+    }
+    if( pFile->h>=0 ){
+      int err = close(pFile->h);
+      if( err ){
+        pFile->lastErrno = errno;
+        return SQLITE_IOERR_CLOSE;
+      }
+    }
+#if OS_VXWORKS
+    if( pFile->pId ){
+      if( pFile->isDelete ){
+        unlink(pFile->pId->zCanonicalName);
+      }
+      vxworksReleaseFileId(pFile->pId);
+      pFile->pId = 0;
+    }
+#endif
+    OSTRACE2("CLOSE   %-3d\n", pFile->h);
+    OpenCounter(-1);
+    sqlite3_free(pFile->pUnused);
+    memset(pFile, 0, sizeof(unixFile));
+  }
+  return SQLITE_OK;
+}
+
+/*
 ** Close a file.
 */
 static int unixClose(sqlite3_file *id){
-  unixFile *pFile = (unixFile *)id;
-  if( !pFile ) return SQLITE_OK;
-  unixUnlock(id, NO_LOCK);
-  if( pFile->dirfd>=0 ) close(pFile->dirfd);
-  pFile->dirfd = -1;
-  enterMutex();
-
-  if( pFile->pOpen->nLock ){
-    /* If there are outstanding locks, do not actually close the file just
-    ** yet because that would clear those locks.  Instead, add the file
-    ** descriptor to pOpen->aPending.  It will be automatically closed when
-    ** the last lock is cleared.
-    */
-    int *aNew;
-    struct openCnt *pOpen = pFile->pOpen;
-    aNew = realloc( pOpen->aPending, (pOpen->nPending+1)*sizeof(int) );
-    if( aNew==0 ){
-      /* If a malloc fails, just leak the file descriptor */
-    }else{
-      pOpen->aPending = aNew;
-      pOpen->aPending[pOpen->nPending] = pFile->h;
-      pOpen->nPending++;
+  int rc = SQLITE_OK;
+  if( id ){
+    unixFile *pFile = (unixFile *)id;
+    unixUnlock(id, NO_LOCK);
+    unixEnterMutex();
+    if( pFile->pOpen && pFile->pOpen->nLock ){
+      /* If there are outstanding locks, do not actually close the file just
+      ** yet because that would clear those locks.  Instead, add the file
+      ** descriptor to pOpen->pUnused list.  It will be automatically closed 
+      ** when the last lock is cleared.
+      */
+      setPendingFd(pFile);
     }
-  }else{
-    /* There are no outstanding locks so we can close the file immediately */
-    close(pFile->h);
+    releaseLockInfo(pFile->pLock);
+    releaseOpenCnt(pFile->pOpen);
+    rc = closeUnixFile(id);
+    unixLeaveMutex();
   }
-  releaseLockInfo(pFile->pLock);
-  releaseOpenCnt(pFile->pOpen);
-
-  leaveMutex();
-  OSTRACE2("CLOSE   %-3d\n", pFile->h);
-  OpenCounter(-1);
-  memset(pFile, 0, sizeof(unixFile));
-  return SQLITE_OK;
+  return rc;
 }
 
+/************** End of the posix advisory lock implementation *****************
+******************************************************************************/
+
+/******************************************************************************
+****************************** No-op Locking **********************************
+**
+** Of the various locking implementations available, this is by far the
+** simplest:  locking is ignored.  No attempt is made to lock the database
+** file for reading or writing.
+**
+** This locking mode is appropriate for use on read-only databases
+** (ex: databases that are burned into CD-ROM, for example.)  It can
+** also be used if the application employs some external mechanism to
+** prevent simultaneous access of the same database by two or more
+** database connections.  But there is a serious risk of database
+** corruption if this locking mode is used in situations where multiple
+** database connections are accessing the same database file at the same
+** time and one or more of those connections are writing.
+*/
 
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-#pragma mark AFP Support
+static int nolockCheckReservedLock(sqlite3_file *NotUsed, int *pResOut){
+  UNUSED_PARAMETER(NotUsed);
+  *pResOut = 0;
+  return SQLITE_OK;
+}
+static int nolockLock(sqlite3_file *NotUsed, int NotUsed2){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  return SQLITE_OK;
+}
+static int nolockUnlock(sqlite3_file *NotUsed, int NotUsed2){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  return SQLITE_OK;
+}
 
 /*
- ** The afpLockingContext structure contains all afp lock specific state
- */
-typedef struct afpLockingContext afpLockingContext;
-struct afpLockingContext {
-  unsigned long long sharedLockByte;
-  const char *filePath;
-};
+** Close the file.
+*/
+static int nolockClose(sqlite3_file *id) {
+  return closeUnixFile(id);
+}
 
-struct ByteRangeLockPB2
-{
-  unsigned long long offset;        /* offset to first byte to lock */
-  unsigned long long length;        /* nbr of bytes to lock */
-  unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */
-  unsigned char unLockFlag;         /* 1 = unlock, 0 = lock */
-  unsigned char startEndFlag;       /* 1=rel to end of fork, 0=rel to start */
-  int fd;                           /* file desc to assoc this lock with */
-};
+/******************* End of the no-op lock implementation *********************
+******************************************************************************/
 
-#define afpfsByteRangeLock2FSCTL        _IOWR('z', 23, struct ByteRangeLockPB2)
+/******************************************************************************
+************************* Begin dot-file Locking ******************************
+**
+** The dotfile locking implementation uses the existance of separate lock
+** files in order to control access to the database.  This works on just
+** about every filesystem imaginable.  But there are serious downsides:
+**
+**    (1)  There is zero concurrency.  A single reader blocks all other
+**         connections from reading or writing the database.
+**
+**    (2)  An application crash or power loss can leave stale lock files
+**         sitting around that need to be cleared manually.
+**
+** Nevertheless, a dotlock is an appropriate locking mode for use if no
+** other locking strategy is available.
+**
+** Dotfile locking works by creating a file in the same directory as the
+** database and with the same name but with a ".lock" extension added.
+** The existance of a lock file implies an EXCLUSIVE lock.  All other lock
+** types (SHARED, RESERVED, PENDING) are mapped into EXCLUSIVE.
+*/
 
-/* 
-** Return 0 on success, 1 on failure.  To match the behavior of the 
-** normal posix file locking (used in unixLock for example), we should 
-** provide 'richer' return codes - specifically to differentiate between
-** 'file busy' and 'file system error' results.
-*/
-static int _AFPFSSetLock(
-  const char *path, 
-  int fd, 
-  unsigned long long offset, 
-  unsigned long long length, 
-  int setLockFlag
-){
-  struct ByteRangeLockPB2       pb;
-  int                     err;
-  
-  pb.unLockFlag = setLockFlag ? 0 : 1;
-  pb.startEndFlag = 0;
-  pb.offset = offset;
-  pb.length = length; 
-  pb.fd = fd;
-  OSTRACE5("AFPLOCK setting lock %s for %d in range %llx:%llx\n", 
-    (setLockFlag?"ON":"OFF"), fd, offset, length);
-  err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
-  if ( err==-1 ) {
-    OSTRACE4("AFPLOCK failed to fsctl() '%s' %d %s\n", path, errno, 
-      strerror(errno));
-    return 1; /* error */
-  } else {
-    return 0;
-  }
-}
+/*
+** The file suffix added to the data base filename in order to create the
+** lock file.
+*/
+#define DOTLOCK_SUFFIX ".lock"
 
 /*
- ** This routine checks if there is a RESERVED lock held on the specified
- ** file by this or any other process. If such a lock is held, return
- ** non-zero.  If the file is unlocked or holds only SHARED locks, then
- ** return zero.
- */
-static int afpUnixCheckReservedLock(sqlite3_file *id){
-  int r = 0;
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+**
+** In dotfile locking, either a lock exists or it does not.  So in this
+** variation of CheckReservedLock(), *pResOut is set to true if any lock
+** is held on the file and false if the file is unlocked.
+*/
+static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
+  int rc = SQLITE_OK;
+  int reserved = 0;
   unixFile *pFile = (unixFile*)id;
+
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
   
-  assert( pFile ); 
-  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
-  
+  assert( pFile );
+
   /* Check if a thread in this process holds such a lock */
   if( pFile->locktype>SHARED_LOCK ){
-    r = 1;
-  }
-  
-  /* Otherwise see if some other process holds it.
-   */
-  if ( !r ) {
-    /* lock the byte */
-    int failed = _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1,1);  
-    if (failed) {
-      /* if we failed to get the lock then someone else must have it */
-      r = 1;
-    } else {
-      /* if we succeeded in taking the reserved lock, unlock it to restore
-      ** the original state */
-      _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1, 0);
-    }
+    /* Either this connection or some other connection in the same process
+    ** holds a lock on the file.  No need to check further. */
+    reserved = 1;
+  }else{
+    /* The lock is held if and only if the lockfile exists */
+    const char *zLockFile = (const char*)pFile->lockingContext;
+    reserved = access(zLockFile, 0)==0;
   }
-  OSTRACE3("TEST WR-LOCK %d %d\n", pFile->h, r);
-  
-  return r;
+  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);
+  *pResOut = reserved;
+  return rc;
 }
 
-/* AFP-style locking following the behavior of unixLock, see the unixLock 
-** function comments for details of lock management. */
-static int afpUnixLock(sqlite3_file *id, int locktype){
-  int rc = SQLITE_OK;
+/*
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock.  Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+**
+** With dotfile locking, we really only support state (4): EXCLUSIVE.
+** But we track the other locking levels internally.
+*/
+static int dotlockLock(sqlite3_file *id, int locktype) {
   unixFile *pFile = (unixFile*)id;
-  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
-  int gotPendingLock = 0;
-  
-  assert( pFile );
-  OSTRACE5("LOCK    %d %s was %s pid=%d\n", pFile->h,
-         locktypeName(locktype), locktypeName(pFile->locktype), getpid());
-
-  /* If there is already a lock of this type or more restrictive on the
-  ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as
-  ** enterMutex() hasn't been called yet.
-  */
-  if( pFile->locktype>=locktype ){
-    OSTRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
-           locktypeName(locktype));
-    return SQLITE_OK;
-  }
+  int fd;
+  char *zLockFile = (char *)pFile->lockingContext;
+  int rc = SQLITE_OK;
 
-  /* Make sure the locking sequence is correct
-  */
-  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
-  assert( locktype!=PENDING_LOCK );
-  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
-  
-  /* This mutex is needed because pFile->pLock is shared across threads
-  */
-  enterMutex();
 
-  /* Make sure the current thread owns the pFile.
-  */
-  rc = transferOwnership(pFile);
-  if( rc!=SQLITE_OK ){
-    leaveMutex();
-    return rc;
-  }
-    
-  /* A PENDING lock is needed before acquiring a SHARED lock and before
-  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
-  ** be released.
+  /* If we have any lock, then the lock file already exists.  All we have
+  ** to do is adjust our internal record of the lock level.
   */
-  if( locktype==SHARED_LOCK 
-      || (locktype==EXCLUSIVE_LOCK && pFile->locktype<PENDING_LOCK)
-  ){
-    int failed;
-    failed = _AFPFSSetLock(context->filePath, pFile->h, PENDING_BYTE, 1, 1);
-    if (failed) {
-      rc = SQLITE_BUSY;
-      goto afp_end_lock;
-    }
+  if( pFile->locktype > NO_LOCK ){
+    pFile->locktype = locktype;
+#if !OS_VXWORKS
+    /* Always update the timestamp on the old file */
+    utimes(zLockFile, NULL);
+#endif
+    return SQLITE_OK;
   }
   
-  /* If control gets to this point, then actually go ahead and make
-  ** operating system calls for the specified lock.
-  */
-  if( locktype==SHARED_LOCK ){
-    int lk, failed;
-    int tries = 0;
-    
-    /* Now get the read-lock */
-    /* note that the quality of the randomness doesn't matter that much */
-    lk = random(); 
-    context->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
-    failed = _AFPFSSetLock(context->filePath, pFile->h, 
-      SHARED_FIRST+context->sharedLockByte, 1, 1);
-    
-    /* Drop the temporary PENDING lock */
-    if (_AFPFSSetLock(context->filePath, pFile->h, PENDING_BYTE, 1, 0)) {
-      rc = SQLITE_IOERR_UNLOCK;  /* This should never happen */
-      goto afp_end_lock;
-    }
-    
-    if( failed ){
+  /* grab an exclusive lock */
+  fd = open(zLockFile,O_RDONLY|O_CREAT|O_EXCL,0600);
+  if( fd<0 ){
+    /* failed to open/create the file, someone else may have stolen the lock */
+    int tErrno = errno;
+    if( EEXIST == tErrno ){
       rc = SQLITE_BUSY;
     } else {
-      pFile->locktype = SHARED_LOCK;
-    }
-  }else{
-    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
-    ** assumed that there is a SHARED or greater lock on the file
-    ** already.
-    */
-    int failed = 0;
-    assert( 0!=pFile->locktype );
-    if (locktype >= RESERVED_LOCK && pFile->locktype < RESERVED_LOCK) {
-        /* Acquire a RESERVED lock */
-        failed = _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1,1);
-    }
-    if (!failed && locktype == EXCLUSIVE_LOCK) {
-      /* Acquire an EXCLUSIVE lock */
-        
-      /* Remove the shared lock before trying the range.  we'll need to 
-      ** reestablish the shared lock if we can't get the  afpUnixUnlock
-      */
-      if (!_AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST +
-                         context->sharedLockByte, 1, 0)) {
-        /* now attemmpt to get the exclusive lock range */
-        failed = _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST, 
-                               SHARED_SIZE, 1);
-        if (failed && _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST +
-                                    context->sharedLockByte, 1, 1)) {
-          rc = SQLITE_IOERR_RDLOCK; /* this should never happen */
-        }
-      } else {
-        /* */
-        rc = SQLITE_IOERR_UNLOCK; /* this should never happen */
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+      if( IS_LOCK_ERROR(rc) ){
+        pFile->lastErrno = tErrno;
       }
     }
-    if( failed && rc == SQLITE_OK){
-      rc = SQLITE_BUSY;
-    }
-  }
-  
-  if( rc==SQLITE_OK ){
-    pFile->locktype = locktype;
-  }else if( locktype==EXCLUSIVE_LOCK ){
-    pFile->locktype = PENDING_LOCK;
+    return rc;
+  } 
+  if( close(fd) ){
+    pFile->lastErrno = errno;
+    rc = SQLITE_IOERR_CLOSE;
   }
   
-afp_end_lock:
-  leaveMutex();
-  OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
-         rc==SQLITE_OK ? "ok" : "failed");
+  /* got it, set the type and return ok */
+  pFile->locktype = locktype;
   return rc;
 }
 
@@ -20585,150 +23460,227 @@ afp_end_lock:
 **
 ** If the locking level of the file descriptor is already at or below
 ** the requested locking level, this routine is a no-op.
+**
+** When the locking level reaches NO_LOCK, delete the lock file.
 */
-static int afpUnixUnlock(sqlite3_file *id, int locktype) {
-  struct flock lock;
-  int rc = SQLITE_OK;
+static int dotlockUnlock(sqlite3_file *id, int locktype) {
   unixFile *pFile = (unixFile*)id;
-  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+  char *zLockFile = (char *)pFile->lockingContext;
 
   assert( pFile );
   OSTRACE5("UNLOCK  %d %d was %d pid=%d\n", pFile->h, locktype,
-         pFile->locktype, getpid());
-  
+	   pFile->locktype, getpid());
   assert( locktype<=SHARED_LOCK );
-  if( pFile->locktype<=locktype ){
+  
+  /* no-op if possible */
+  if( pFile->locktype==locktype ){
     return SQLITE_OK;
   }
-  if( CHECK_THREADID(pFile) ){
-    return SQLITE_MISUSE;
+
+  /* To downgrade to shared, simply update our internal notion of the
+  ** lock state.  No need to mess with the file on disk.
+  */
+  if( locktype==SHARED_LOCK ){
+    pFile->locktype = SHARED_LOCK;
+    return SQLITE_OK;
   }
-  enterMutex();
-  if( pFile->locktype>SHARED_LOCK ){
-    if( locktype==SHARED_LOCK ){
-      int failed = 0;
-
-      /* unlock the exclusive range - then re-establish the shared lock */
-      if (pFile->locktype==EXCLUSIVE_LOCK) {
-        failed = _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST, 
-                                 SHARED_SIZE, 0);
-        if (!failed) {
-          /* successfully removed the exclusive lock */
-          if (_AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST+
-                            context->sharedLockByte, 1, 1)) {
-            /* failed to re-establish our shared lock */
-            rc = SQLITE_IOERR_RDLOCK; /* This should never happen */
-          }
-        } else {
-          /* This should never happen - failed to unlock the exclusive range */
-          rc = SQLITE_IOERR_UNLOCK;
-        } 
-      }
+  
+  /* To fully unlock the database, delete the lock file */
+  assert( locktype==NO_LOCK );
+  if( unlink(zLockFile) ){
+    int rc = 0;
+    int tErrno = errno;
+    if( ENOENT != tErrno ){
+      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
     }
-    if (rc == SQLITE_OK && pFile->locktype>=PENDING_LOCK) {
-      if (_AFPFSSetLock(context->filePath, pFile->h, PENDING_BYTE, 1, 0)){
-        /* failed to release the pending lock */
-        rc = SQLITE_IOERR_UNLOCK; /* This should never happen */
-      }
-    } 
-    if (rc == SQLITE_OK && pFile->locktype>=RESERVED_LOCK) {
-      if (_AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1, 0)) {
-        /* failed to release the reserved lock */
-        rc = SQLITE_IOERR_UNLOCK;  /* This should never happen */
-      }
-    } 
-  }
-  if( locktype==NO_LOCK ){
-    int failed = _AFPFSSetLock(context->filePath, pFile->h, 
-                               SHARED_FIRST + context->sharedLockByte, 1, 0);
-    if (failed) {
-      rc = SQLITE_IOERR_UNLOCK;  /* This should never happen */
+    if( IS_LOCK_ERROR(rc) ){
+      pFile->lastErrno = tErrno;
     }
+    return rc; 
   }
-  if (rc == SQLITE_OK)
-    pFile->locktype = locktype;
-  leaveMutex();
-  return rc;
+  pFile->locktype = NO_LOCK;
+  return SQLITE_OK;
 }
 
 /*
-** Close a file & cleanup AFP specific locking context 
+** Close a file.  Make sure the lock has been released before closing.
 */
-static int afpUnixClose(sqlite3_file *id) {
-  unixFile *pFile = (unixFile*)id;
-
-  if( !pFile ) return SQLITE_OK;
-  afpUnixUnlock(id, NO_LOCK);
-  sqlite3_free(pFile->lockingContext);
-  if( pFile->dirfd>=0 ) close(pFile->dirfd);
-  pFile->dirfd = -1;
-  enterMutex();
-  close(pFile->h);
-  leaveMutex();
-  OSTRACE2("CLOSE   %-3d\n", pFile->h);
-  OpenCounter(-1);
-  memset(pFile, 0, sizeof(unixFile));
-  return SQLITE_OK;
+static int dotlockClose(sqlite3_file *id) {
+  int rc;
+  if( id ){
+    unixFile *pFile = (unixFile*)id;
+    dotlockUnlock(id, NO_LOCK);
+    sqlite3_free(pFile->lockingContext);
+  }
+  rc = closeUnixFile(id);
+  return rc;
 }
+/****************** End of the dot-file lock implementation *******************
+******************************************************************************/
 
-
-#pragma mark flock() style locking
+/******************************************************************************
+************************** Begin flock Locking ********************************
+**
+** Use the flock() system call to do file locking.
+**
+** flock() locking is like dot-file locking in that the various
+** fine-grain locking levels supported by SQLite are collapsed into
+** a single exclusive lock.  In other words, SHARED, RESERVED, and
+** PENDING locks are the same thing as an EXCLUSIVE lock.  SQLite
+** still works when you do this, but concurrency is reduced since
+** only a single process can be reading the database at a time.
+**
+** Omit this section if SQLITE_ENABLE_LOCKING_STYLE is turned off or if
+** compiling for VXWORKS.
+*/
+#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
 
 /*
-** The flockLockingContext is not used
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
 */
-typedef void flockLockingContext;
-
-static int flockUnixCheckReservedLock(sqlite3_file *id){
+static int flockCheckReservedLock(sqlite3_file *id, int *pResOut){
+  int rc = SQLITE_OK;
+  int reserved = 0;
   unixFile *pFile = (unixFile*)id;
   
-  if (pFile->locktype == RESERVED_LOCK) {
-    return 1; /* already have a reserved lock */
-  } else {
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+  
+  assert( pFile );
+  
+  /* Check if a thread in this process holds such a lock */
+  if( pFile->locktype>SHARED_LOCK ){
+    reserved = 1;
+  }
+  
+  /* Otherwise see if some other process holds it. */
+  if( !reserved ){
     /* attempt to get the lock */
-    int rc = flock(pFile->h, LOCK_EX | LOCK_NB);
-    if (!rc) {
+    int lrc = flock(pFile->h, LOCK_EX | LOCK_NB);
+    if( !lrc ){
       /* got the lock, unlock it */
-      flock(pFile->h, LOCK_UN);
-      return 0;  /* no one has it reserved */
+      lrc = flock(pFile->h, LOCK_UN);
+      if ( lrc ) {
+        int tErrno = errno;
+        /* unlock failed with an error */
+        lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK); 
+        if( IS_LOCK_ERROR(lrc) ){
+          pFile->lastErrno = tErrno;
+          rc = lrc;
+        }
+      }
+    } else {
+      int tErrno = errno;
+      reserved = 1;
+      /* someone else might have it reserved */
+      lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK); 
+      if( IS_LOCK_ERROR(lrc) ){
+        pFile->lastErrno = tErrno;
+        rc = lrc;
+      }
     }
-    return 1; /* someone else might have it reserved */
   }
-}
+  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);
 
-static int flockUnixLock(sqlite3_file *id, int locktype) {
-  unixFile *pFile = (unixFile*)id;
-  
-  /* if we already have a lock, it is exclusive.  
-  ** Just adjust level and punt on outta here. */
-  if (pFile->locktype > NO_LOCK) {
-    pFile->locktype = locktype;
-    return SQLITE_OK;
-  }
-  
-  /* grab an exclusive lock */
-  int rc = flock(pFile->h, LOCK_EX | LOCK_NB);
-  if (rc) {
-    /* didn't get, must be busy */
-    return SQLITE_BUSY;
-  } else {
-    /* got it, set the type and return ok */
-    pFile->locktype = locktype;
-    return SQLITE_OK;
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
+    rc = SQLITE_OK;
+    reserved=1;
   }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+  *pResOut = reserved;
+  return rc;
 }
 
-static int flockUnixUnlock(sqlite3_file *id, int locktype) {
-  unixFile *pFile = (unixFile*)id;
-  
-  assert( locktype<=SHARED_LOCK );
-  
-  /* no-op if possible */
-  if( pFile->locktype==locktype ){
-    return SQLITE_OK;
-  }
-  
-  /* shared can just be set because we always have an exclusive */
+/*
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
+**
+** flock() only really support EXCLUSIVE locks.  We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock.  Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int flockLock(sqlite3_file *id, int locktype) {
+  int rc = SQLITE_OK;
+  unixFile *pFile = (unixFile*)id;
+
+  assert( pFile );
+
+  /* if we already have a lock, it is exclusive.  
+  ** Just adjust level and punt on outta here. */
+  if (pFile->locktype > NO_LOCK) {
+    pFile->locktype = locktype;
+    return SQLITE_OK;
+  }
+  
+  /* grab an exclusive lock */
+  
+  if (flock(pFile->h, LOCK_EX | LOCK_NB)) {
+    int tErrno = errno;
+    /* didn't get, must be busy */
+    rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+    if( IS_LOCK_ERROR(rc) ){
+      pFile->lastErrno = tErrno;
+    }
+  } else {
+    /* got it, set the type and return ok */
+    pFile->locktype = locktype;
+  }
+  OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
+           rc==SQLITE_OK ? "ok" : "failed");
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
+    rc = SQLITE_BUSY;
+  }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+  return rc;
+}
+
+
+/*
+** Lower the locking level on file descriptor pFile to locktype.  locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int flockUnlock(sqlite3_file *id, int locktype) {
+  unixFile *pFile = (unixFile*)id;
+  
+  assert( pFile );
+  OSTRACE5("UNLOCK  %d %d was %d pid=%d\n", pFile->h, locktype,
+           pFile->locktype, getpid());
+  assert( locktype<=SHARED_LOCK );
+  
+  /* no-op if possible */
+  if( pFile->locktype==locktype ){
+    return SQLITE_OK;
+  }
+  
+  /* shared can just be set because we always have an exclusive */
   if (locktype==SHARED_LOCK) {
     pFile->locktype = locktype;
     return SQLITE_OK;
@@ -20736,9 +23688,20 @@ static int flockUnixUnlock(sqlite3_file *id, int locktype) {
   
   /* no, really, unlock. */
   int rc = flock(pFile->h, LOCK_UN);
-  if (rc)
-    return SQLITE_IOERR_UNLOCK;
-  else {
+  if (rc) {
+    int r, tErrno = errno;
+    r = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+    if( IS_LOCK_ERROR(r) ){
+      pFile->lastErrno = tErrno;
+    }
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+    if( (r & SQLITE_IOERR) == SQLITE_IOERR ){
+      r = SQLITE_BUSY;
+    }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+    
+    return r;
+  } else {
     pFile->locktype = NO_LOCK;
     return SQLITE_OK;
   }
@@ -20747,97 +23710,146 @@ static int flockUnixUnlock(sqlite3_file *id, int locktype) {
 /*
 ** Close a file.
 */
-static int flockUnixClose(sqlite3_file *id) {
-  unixFile *pFile = (unixFile*)id;
-  
-  if( !pFile ) return SQLITE_OK;
-  flockUnixUnlock(id, NO_LOCK);
-  
-  if( pFile->dirfd>=0 ) close(pFile->dirfd);
-  pFile->dirfd = -1;
-
-  enterMutex();
-  close(pFile->h);  
-  leaveMutex();
-  OSTRACE2("CLOSE   %-3d\n", pFile->h);
-  OpenCounter(-1);
-  memset(pFile, 0, sizeof(unixFile));
-  return SQLITE_OK;
+static int flockClose(sqlite3_file *id) {
+  if( id ){
+    flockUnlock(id, NO_LOCK);
+  }
+  return closeUnixFile(id);
 }
 
-#pragma mark Old-School .lock file based locking
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */
 
-/*
-** The dotlockLockingContext structure contains all dotlock (.lock) lock
-** specific state
-*/
-typedef struct dotlockLockingContext dotlockLockingContext;
-struct dotlockLockingContext {
-  char *lockPath;
-};
+/******************* End of the flock lock implementation *********************
+******************************************************************************/
 
+/******************************************************************************
+************************ Begin Named Semaphore Locking ************************
+**
+** Named semaphore locking is only supported on VxWorks.
+**
+** Semaphore locking is like dot-lock and flock in that it really only
+** supports EXCLUSIVE locking.  Only a single process can read or write
+** the database file at a time.  This reduces potential concurrency, but
+** makes the lock implementation much easier.
+*/
+#if OS_VXWORKS
 
-static int dotlockUnixCheckReservedLock(sqlite3_file *id) {
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int semCheckReservedLock(sqlite3_file *id, int *pResOut) {
+  int rc = SQLITE_OK;
+  int reserved = 0;
   unixFile *pFile = (unixFile*)id;
-  dotlockLockingContext *context;
 
-  context = (dotlockLockingContext*)pFile->lockingContext;
-  if (pFile->locktype == RESERVED_LOCK) {
-    return 1; /* already have a reserved lock */
-  } else {
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+  
+  assert( pFile );
+
+  /* Check if a thread in this process holds such a lock */
+  if( pFile->locktype>SHARED_LOCK ){
+    reserved = 1;
+  }
+  
+  /* Otherwise see if some other process holds it. */
+  if( !reserved ){
+    sem_t *pSem = pFile->pOpen->pSem;
     struct stat statBuf;
-    if (lstat(context->lockPath,&statBuf) == 0){
-      /* file exists, someone else has the lock */
-      return 1;
+
+    if( sem_trywait(pSem)==-1 ){
+      int tErrno = errno;
+      if( EAGAIN != tErrno ){
+        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
+        pFile->lastErrno = tErrno;
+      } else {
+        /* someone else has the lock when we are in NO_LOCK */
+        reserved = (pFile->locktype < SHARED_LOCK);
+      }
     }else{
-      /* file does not exist, we could have it if we want it */
-      return 0;
+      /* we could have it if we want it */
+      sem_post(pSem);
     }
   }
+  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);
+
+  *pResOut = reserved;
+  return rc;
 }
 
-static int dotlockUnixLock(sqlite3_file *id, int locktype) {
+/*
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
+**
+** Semaphore locks only really support EXCLUSIVE locks.  We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock.  Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int semLock(sqlite3_file *id, int locktype) {
   unixFile *pFile = (unixFile*)id;
-  dotlockLockingContext *context;
   int fd;
+  sem_t *pSem = pFile->pOpen->pSem;
+  int rc = SQLITE_OK;
 
-  context = (dotlockLockingContext*)pFile->lockingContext;
-  
   /* if we already have a lock, it is exclusive.  
   ** Just adjust level and punt on outta here. */
   if (pFile->locktype > NO_LOCK) {
     pFile->locktype = locktype;
-    
-    /* Always update the timestamp on the old file */
-    utimes(context->lockPath,NULL);
-    return SQLITE_OK;
-  }
-  
-  /* check to see if lock file already exists */
-  struct stat statBuf;
-  if (lstat(context->lockPath,&statBuf) == 0){
-    return SQLITE_BUSY; /* it does, busy */
+    rc = SQLITE_OK;
+    goto sem_end_lock;
   }
   
-  /* grab an exclusive lock */
-  fd = open(context->lockPath,O_RDONLY|O_CREAT|O_EXCL,0600);
-  if( fd<0 ){
-    /* failed to open/create the file, someone else may have stolen the lock */
-    return SQLITE_BUSY; 
+  /* lock semaphore now but bail out when already locked. */
+  if( sem_trywait(pSem)==-1 ){
+    rc = SQLITE_BUSY;
+    goto sem_end_lock;
   }
-  close(fd);
-  
+
   /* got it, set the type and return ok */
   pFile->locktype = locktype;
-  return SQLITE_OK;
+
+ sem_end_lock:
+  return rc;
 }
 
-static int dotlockUnixUnlock(sqlite3_file *id, int locktype) {
+/*
+** Lower the locking level on file descriptor pFile to locktype.  locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int semUnlock(sqlite3_file *id, int locktype) {
   unixFile *pFile = (unixFile*)id;
-  dotlockLockingContext *context;
+  sem_t *pSem = pFile->pOpen->pSem;
 
-  context = (dotlockLockingContext*)pFile->lockingContext;
-  
+  assert( pFile );
+  assert( pSem );
+  OSTRACE5("UNLOCK  %d %d was %d pid=%d\n", pFile->h, locktype,
+	   pFile->locktype, getpid());
   assert( locktype<=SHARED_LOCK );
   
   /* no-op if possible */
@@ -20851,8 +23863,15 @@ static int dotlockUnixUnlock(sqlite3_file *id, int locktype) {
     return SQLITE_OK;
   }
   
-  /* no, really, unlock. */
-  unlink(context->lockPath);
+  /* no, really unlock. */
+  if ( sem_post(pSem)==-1 ) {
+    int rc, tErrno = errno;
+    rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+    if( IS_LOCK_ERROR(rc) ){
+      pFile->lastErrno = tErrno;
+    }
+    return rc; 
+  }
   pFile->locktype = NO_LOCK;
   return SQLITE_OK;
 }
@@ -20860,2527 +23879,3142 @@ static int dotlockUnixUnlock(sqlite3_file *id, int locktype) {
 /*
  ** Close a file.
  */
-static int dotlockUnixClose(sqlite3_file *id) {
-  unixFile *pFile = (unixFile*)id;
-  
-  if( !pFile ) return SQLITE_OK;
-  dotlockUnixUnlock(id, NO_LOCK);
-  sqlite3_free(pFile->lockingContext);
-  if( pFile->dirfd>=0 ) close(pFile->dirfd);
-  pFile->dirfd = -1;
-  enterMutex();  
-  close(pFile->h);
-  leaveMutex();
-  OSTRACE2("CLOSE   %-3d\n", pFile->h);
-  OpenCounter(-1);
-  memset(pFile, 0, sizeof(unixFile));
+static int semClose(sqlite3_file *id) {
+  if( id ){
+    unixFile *pFile = (unixFile*)id;
+    semUnlock(id, NO_LOCK);
+    assert( pFile );
+    unixEnterMutex();
+    releaseLockInfo(pFile->pLock);
+    releaseOpenCnt(pFile->pOpen);
+    unixLeaveMutex();
+    closeUnixFile(id);
+  }
   return SQLITE_OK;
 }
 
-
-#pragma mark No locking
-
+#endif /* OS_VXWORKS */
 /*
-** The nolockLockingContext is void
-*/
-typedef void nolockLockingContext;
-
-static int nolockUnixCheckReservedLock(sqlite3_file *id) {
-  return 0;
-}
+** Named semaphore locking is only available on VxWorks.
+**
+*************** End of the named semaphore lock implementation ****************
+******************************************************************************/
 
-static int nolockUnixLock(sqlite3_file *id, int locktype) {
-  return SQLITE_OK;
-}
 
-static int nolockUnixUnlock(sqlite3_file *id, int locktype) {
-  return SQLITE_OK;
-}
+/******************************************************************************
+*************************** Begin AFP Locking *********************************
+**
+** AFP is the Apple Filing Protocol.  AFP is a network filesystem found
+** on Apple Macintosh computers - both OS9 and OSX.
+**
+** Third-party implementations of AFP are available.  But this code here
+** only works on OSX.
+*/
 
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
 /*
-** Close a file.
+** The afpLockingContext structure contains all afp lock specific state
 */
-static int nolockUnixClose(sqlite3_file *id) {
-  unixFile *pFile = (unixFile*)id;
-  
-  if( !pFile ) return SQLITE_OK;
-  if( pFile->dirfd>=0 ) close(pFile->dirfd);
-  pFile->dirfd = -1;
-  enterMutex();
-  close(pFile->h);
-  leaveMutex();
-  OSTRACE2("CLOSE   %-3d\n", pFile->h);
-  OpenCounter(-1);
-  memset(pFile, 0, sizeof(unixFile));
-  return SQLITE_OK;
-}
+typedef struct afpLockingContext afpLockingContext;
+struct afpLockingContext {
+  unsigned long long sharedByte;
+  const char *dbPath;             /* Name of the open file */
+};
 
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
+struct ByteRangeLockPB2
+{
+  unsigned long long offset;        /* offset to first byte to lock */
+  unsigned long long length;        /* nbr of bytes to lock */
+  unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */
+  unsigned char unLockFlag;         /* 1 = unlock, 0 = lock */
+  unsigned char startEndFlag;       /* 1=rel to end of fork, 0=rel to start */
+  int fd;                           /* file desc to assoc this lock with */
+};
 
+#define afpfsByteRangeLock2FSCTL        _IOWR('z', 23, struct ByteRangeLockPB2)
 
 /*
-** Information and control of an open file handle.
-*/
-static int unixFileControl(sqlite3_file *id, int op, void *pArg){
-  switch( op ){
-    case SQLITE_FCNTL_LOCKSTATE: {
-      *(int*)pArg = ((unixFile*)id)->locktype;
-      return SQLITE_OK;
+** This is a utility for setting or clearing a bit-range lock on an
+** AFP filesystem.
+** 
+** Return SQLITE_OK on success, SQLITE_BUSY on failure.
+*/
+static int afpSetLock(
+  const char *path,              /* Name of the file to be locked or unlocked */
+  unixFile *pFile,               /* Open file descriptor on path */
+  unsigned long long offset,     /* First byte to be locked */
+  unsigned long long length,     /* Number of bytes to lock */
+  int setLockFlag                /* True to set lock.  False to clear lock */
+){
+  struct ByteRangeLockPB2 pb;
+  int err;
+  
+  pb.unLockFlag = setLockFlag ? 0 : 1;
+  pb.startEndFlag = 0;
+  pb.offset = offset;
+  pb.length = length; 
+  pb.fd = pFile->h;
+  
+  OSTRACE6("AFPSETLOCK [%s] for %d%s in range %llx:%llx\n", 
+    (setLockFlag?"ON":"OFF"), pFile->h, (pb.fd==-1?"[testval-1]":""),
+    offset, length);
+  err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
+  if ( err==-1 ) {
+    int rc;
+    int tErrno = errno;
+    OSTRACE4("AFPSETLOCK failed to fsctl() '%s' %d %s\n",
+             path, tErrno, strerror(tErrno));
+#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
+    rc = SQLITE_BUSY;
+#else
+    rc = sqliteErrorFromPosixError(tErrno,
+                    setLockFlag ? SQLITE_IOERR_LOCK : SQLITE_IOERR_UNLOCK);
+#endif /* SQLITE_IGNORE_AFP_LOCK_ERRORS */
+    if( IS_LOCK_ERROR(rc) ){
+      pFile->lastErrno = tErrno;
     }
+    return rc;
+  } else {
+    return SQLITE_OK;
   }
-  return SQLITE_ERROR;
-}
-
-/*
-** Return the sector size in bytes of the underlying block device for
-** the specified file. This is almost always 512 bytes, but may be
-** larger for some devices.
-**
-** SQLite code assumes this function cannot fail. It also assumes that
-** if two files are created in the same file-system directory (i.e.
-** a database and its journal file) that the sector size will be the
-** same for both.
-*/
-static int unixSectorSize(sqlite3_file *id){
-  return SQLITE_DEFAULT_SECTOR_SIZE;
 }
 
 /*
-** Return the device characteristics for the file. This is always 0.
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
 */
-static int unixDeviceCharacteristics(sqlite3_file *id){
-  return 0;
+static int afpCheckReservedLock(sqlite3_file *id, int *pResOut){
+  int rc = SQLITE_OK;
+  int reserved = 0;
+  unixFile *pFile = (unixFile*)id;
+  
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+  
+  assert( pFile );
+  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+  
+  /* Check if a thread in this process holds such a lock */
+  if( pFile->locktype>SHARED_LOCK ){
+    reserved = 1;
+  }
+  
+  /* Otherwise see if some other process holds it.
+   */
+  if( !reserved ){
+    /* lock the RESERVED byte */
+    int lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);  
+    if( SQLITE_OK==lrc ){
+      /* if we succeeded in taking the reserved lock, unlock it to restore
+      ** the original state */
+      lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
+    } else {
+      /* if we failed to get the lock then someone else must have it */
+      reserved = 1;
+    }
+    if( IS_LOCK_ERROR(lrc) ){
+      rc=lrc;
+    }
+  }
+  
+  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);
+  
+  *pResOut = reserved;
+  return rc;
 }
 
 /*
-** This vector defines all the methods that can operate on an sqlite3_file
-** for unix.
-*/
-static const sqlite3_io_methods sqlite3UnixIoMethod = {
-  1,                        /* iVersion */
-  unixClose,
-  unixRead,
-  unixWrite,
-  unixTruncate,
-  unixSync,
-  unixFileSize,
-  unixLock,
-  unixUnlock,
-  unixCheckReservedLock,
-  unixFileControl,
-  unixSectorSize,
-  unixDeviceCharacteristics
-};
-
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-/*
-** This vector defines all the methods that can operate on an sqlite3_file
-** for unix with AFP style file locking.
-*/
-static const sqlite3_io_methods sqlite3AFPLockingUnixIoMethod = {
-  1,                        /* iVersion */
-  afpUnixClose,
-  unixRead,
-  unixWrite,
-  unixTruncate,
-  unixSync,
-  unixFileSize,
-  afpUnixLock,
-  afpUnixUnlock,
-  afpUnixCheckReservedLock,
-  unixFileControl,
-  unixSectorSize,
-  unixDeviceCharacteristics
-};
-
-/*
-** This vector defines all the methods that can operate on an sqlite3_file
-** for unix with flock() style file locking.
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock.  Use the sqlite3OsUnlock()
+** routine to lower a locking level.
 */
-static const sqlite3_io_methods sqlite3FlockLockingUnixIoMethod = {
-  1,                        /* iVersion */
-  flockUnixClose,
-  unixRead,
-  unixWrite,
-  unixTruncate,
-  unixSync,
-  unixFileSize,
-  flockUnixLock,
-  flockUnixUnlock,
-  flockUnixCheckReservedLock,
-  unixFileControl,
-  unixSectorSize,
-  unixDeviceCharacteristics
-};
+static int afpLock(sqlite3_file *id, int locktype){
+  int rc = SQLITE_OK;
+  unixFile *pFile = (unixFile*)id;
+  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+  
+  assert( pFile );
+  OSTRACE5("LOCK    %d %s was %s pid=%d\n", pFile->h,
+         locktypeName(locktype), locktypeName(pFile->locktype), getpid());
 
-/*
-** This vector defines all the methods that can operate on an sqlite3_file
-** for unix with dotlock style file locking.
-*/
-static const sqlite3_io_methods sqlite3DotlockLockingUnixIoMethod = {
-  1,                        /* iVersion */
-  dotlockUnixClose,
-  unixRead,
-  unixWrite,
-  unixTruncate,
-  unixSync,
-  unixFileSize,
-  dotlockUnixLock,
-  dotlockUnixUnlock,
-  dotlockUnixCheckReservedLock,
-  unixFileControl,
-  unixSectorSize,
-  unixDeviceCharacteristics
-};
+  /* If there is already a lock of this type or more restrictive on the
+  ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as
+  ** unixEnterMutex() hasn't been called yet.
+  */
+  if( pFile->locktype>=locktype ){
+    OSTRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
+           locktypeName(locktype));
+    return SQLITE_OK;
+  }
 
-/*
-** This vector defines all the methods that can operate on an sqlite3_file
-** for unix with nolock style file locking.
-*/
-static const sqlite3_io_methods sqlite3NolockLockingUnixIoMethod = {
-  1,                        /* iVersion */
-  nolockUnixClose,
-  unixRead,
-  unixWrite,
-  unixTruncate,
-  unixSync,
-  unixFileSize,
-  nolockUnixLock,
-  nolockUnixUnlock,
-  nolockUnixCheckReservedLock,
-  unixFileControl,
-  unixSectorSize,
-  unixDeviceCharacteristics
-};
+  /* Make sure the locking sequence is correct
+  */
+  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
+  assert( locktype!=PENDING_LOCK );
+  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
+  
+  /* This mutex is needed because pFile->pLock is shared across threads
+  */
+  unixEnterMutex();
 
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
+  /* Make sure the current thread owns the pFile.
+  */
+  rc = transferOwnership(pFile);
+  if( rc!=SQLITE_OK ){
+    unixLeaveMutex();
+    return rc;
+  }
+    
+  /* A PENDING lock is needed before acquiring a SHARED lock and before
+  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
+  ** be released.
+  */
+  if( locktype==SHARED_LOCK 
+      || (locktype==EXCLUSIVE_LOCK && pFile->locktype<PENDING_LOCK)
+  ){
+    int failed;
+    failed = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 1);
+    if (failed) {
+      rc = failed;
+      goto afp_end_lock;
+    }
+  }
+  
+  /* If control gets to this point, then actually go ahead and make
+  ** operating system calls for the specified lock.
+  */
+  if( locktype==SHARED_LOCK ){
+    int lk, lrc1, lrc2, lrc1Errno;
+    
+    /* Now get the read-lock SHARED_LOCK */
+    /* note that the quality of the randomness doesn't matter that much */
+    lk = random(); 
+    context->sharedByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
+    lrc1 = afpSetLock(context->dbPath, pFile, 
+          SHARED_FIRST+context->sharedByte, 1, 1);
+    if( IS_LOCK_ERROR(lrc1) ){
+      lrc1Errno = pFile->lastErrno;
+    }
+    /* Drop the temporary PENDING lock */
+    lrc2 = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
+    
+    if( IS_LOCK_ERROR(lrc1) ) {
+      pFile->lastErrno = lrc1Errno;
+      rc = lrc1;
+      goto afp_end_lock;
+    } else if( IS_LOCK_ERROR(lrc2) ){
+      rc = lrc2;
+      goto afp_end_lock;
+    } else if( lrc1 != SQLITE_OK ) {
+      rc = lrc1;
+    } else {
+      pFile->locktype = SHARED_LOCK;
+      pFile->pOpen->nLock++;
+    }
+  }else{
+    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
+    ** assumed that there is a SHARED or greater lock on the file
+    ** already.
+    */
+    int failed = 0;
+    assert( 0!=pFile->locktype );
+    if (locktype >= RESERVED_LOCK && pFile->locktype < RESERVED_LOCK) {
+        /* Acquire a RESERVED lock */
+        failed = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
+    }
+    if (!failed && locktype == EXCLUSIVE_LOCK) {
+      /* Acquire an EXCLUSIVE lock */
+        
+      /* Remove the shared lock before trying the range.  we'll need to 
+      ** reestablish the shared lock if we can't get the  afpUnlock
+      */
+      if( !(failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST +
+                         context->sharedByte, 1, 0)) ){
+        int failed2 = SQLITE_OK;
+        /* now attemmpt to get the exclusive lock range */
+        failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST, 
+                               SHARED_SIZE, 1);
+        if( failed && (failed2 = afpSetLock(context->dbPath, pFile, 
+                       SHARED_FIRST + context->sharedByte, 1, 1)) ){
+          /* Can't reestablish the shared lock.  Sqlite can't deal, this is
+          ** a critical I/O error
+          */
+          rc = ((failed & SQLITE_IOERR) == SQLITE_IOERR) ? failed2 : 
+               SQLITE_IOERR_LOCK;
+          goto afp_end_lock;
+        } 
+      }else{
+        rc = failed; 
+      }
+    }
+    if( failed ){
+      rc = failed;
+    }
+  }
+  
+  if( rc==SQLITE_OK ){
+    pFile->locktype = locktype;
+  }else if( locktype==EXCLUSIVE_LOCK ){
+    pFile->locktype = PENDING_LOCK;
+  }
+  
+afp_end_lock:
+  unixLeaveMutex();
+  OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
+         rc==SQLITE_OK ? "ok" : "failed");
+  return rc;
+}
 
 /*
-** Allocate memory for a new unixFile and initialize that unixFile.
-** Write a pointer to the new unixFile into *pId.
-** If we run out of memory, close the file and return an error.
-*/
-#ifdef SQLITE_ENABLE_LOCKING_STYLE
-/* 
-** When locking extensions are enabled, the filepath and locking style 
-** are needed to determine the unixFile pMethod to use for locking operations.
-** The locking-style specific lockingContext data structure is created 
-** and assigned here also.
+** Lower the locking level on file descriptor pFile to locktype.  locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
 */
-static int fillInUnixFile(
-  int h,                  /* Open file descriptor of file being opened */
-  int dirfd,              /* Directory file descriptor */
-  sqlite3_file *pId,      /* Write to the unixFile structure here */
-  const char *zFilename   /* Name of the file being opened */
-){
-  sqlite3LockingStyle lockingStyle;
-  unixFile *pNew = (unixFile *)pId;
-  int rc;
+static int afpUnlock(sqlite3_file *id, int locktype) {
+  int rc = SQLITE_OK;
+  unixFile *pFile = (unixFile*)id;
+  afpLockingContext *pCtx = (afpLockingContext *) pFile->lockingContext;
 
-#ifdef FD_CLOEXEC
-  fcntl(h, F_SETFD, fcntl(h, F_GETFD, 0) | FD_CLOEXEC);
-#endif
+  assert( pFile );
+  OSTRACE5("UNLOCK  %d %d was %d pid=%d\n", pFile->h, locktype,
+         pFile->locktype, getpid());
 
-  lockingStyle = sqlite3DetectLockingStyle(zFilename, h);
-  if ( lockingStyle==posixLockingStyle ){
-    enterMutex();
-    rc = findLockInfo(h, &pNew->pLock, &pNew->pOpen);
-    leaveMutex();
-    if( rc ){
-      if( dirfd>=0 ) close(dirfd);
-      close(h);
-      return rc;
-    }
-  } else {
-    /*  pLock and pOpen are only used for posix advisory locking */
-    pNew->pLock = NULL;
-    pNew->pOpen = NULL;
+  assert( locktype<=SHARED_LOCK );
+  if( pFile->locktype<=locktype ){
+    return SQLITE_OK;
   }
-
-  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);    
-  pNew->dirfd = -1;
-  pNew->h = h;
-  pNew->dirfd = dirfd;
-  SET_THREADID(pNew);
+  if( CHECK_THREADID(pFile) ){
+    return SQLITE_MISUSE;
+  }
+  unixEnterMutex();
+  if( pFile->locktype>SHARED_LOCK ){
     
-  switch(lockingStyle) {
-    case afpLockingStyle: {
-      /* afp locking uses the file path so it needs to be included in
-      ** the afpLockingContext */
-      afpLockingContext *context;
-      pNew->pMethod = &sqlite3AFPLockingUnixIoMethod;
-      pNew->lockingContext = context = sqlite3_malloc( sizeof(*context) );
-      if( context==0 ){
-        close(h);
-        if( dirfd>=0 ) close(dirfd);
-        return SQLITE_NOMEM;
+    if( pFile->locktype==EXCLUSIVE_LOCK ){
+      rc = afpSetLock(pCtx->dbPath, pFile, SHARED_FIRST, SHARED_SIZE, 0);
+      if( rc==SQLITE_OK && locktype==SHARED_LOCK ){
+        /* only re-establish the shared lock if necessary */
+        int sharedLockByte = SHARED_FIRST+pCtx->sharedByte;
+        rc = afpSetLock(pCtx->dbPath, pFile, sharedLockByte, 1, 1);
       }
-
-      /* NB: zFilename exists and remains valid until the file is closed
-      ** according to requirement F11141.  So we do not need to make a
-      ** copy of the filename. */
-      context->filePath = zFilename;
-      srandomdev();
-      break;
     }
-    case flockLockingStyle:
-      /* flock locking doesn't need additional lockingContext information */
-      pNew->pMethod = &sqlite3FlockLockingUnixIoMethod;
-      break;
-    case dotlockLockingStyle: {
-      /* dotlock locking uses the file path so it needs to be included in
-      ** the dotlockLockingContext */
-      dotlockLockingContext *context;
-      int nFilename;
-      nFilename = strlen(zFilename);
-      pNew->pMethod = &sqlite3DotlockLockingUnixIoMethod;
-      pNew->lockingContext = context = 
-         sqlite3_malloc( sizeof(*context) + nFilename + 6 );
-      if( context==0 ){
-        close(h);
-        if( dirfd>=0 ) close(dirfd);
-        return SQLITE_NOMEM;
+    if( rc==SQLITE_OK && pFile->locktype>=PENDING_LOCK ){
+      rc = afpSetLock(pCtx->dbPath, pFile, PENDING_BYTE, 1, 0);
+    } 
+    if( rc==SQLITE_OK && pFile->locktype>=RESERVED_LOCK ){
+      rc = afpSetLock(pCtx->dbPath, pFile, RESERVED_BYTE, 1, 0);
+    }
+  }else if( locktype==NO_LOCK ){
+    /* clear the shared lock */
+    int sharedLockByte = SHARED_FIRST+pCtx->sharedByte;
+    rc = afpSetLock(pCtx->dbPath, pFile, sharedLockByte, 1, 0);
+  }
+
+  if( rc==SQLITE_OK ){
+    if( locktype==NO_LOCK ){
+      struct unixOpenCnt *pOpen = pFile->pOpen;
+      pOpen->nLock--;
+      assert( pOpen->nLock>=0 );
+      if( pOpen->nLock==0 ){
+        rc = closePendingFds(pFile);
       }
-      context->lockPath = (char*)&context[1];
-      sqlite3_snprintf(nFilename, context->lockPath,
-                       "%s.lock", zFilename);
-      break;
     }
-    case posixLockingStyle:
-      /* posix locking doesn't need additional lockingContext information */
-      pNew->pMethod = &sqlite3UnixIoMethod;
-      break;
-    case noLockingStyle:
-    case unsupportedLockingStyle:
-    default: 
-      pNew->pMethod = &sqlite3NolockLockingUnixIoMethod;
   }
-  OpenCounter(+1);
-  return SQLITE_OK;
+  unixLeaveMutex();
+  if( rc==SQLITE_OK ){
+    pFile->locktype = locktype;
+  }
+  return rc;
 }
-#else /* SQLITE_ENABLE_LOCKING_STYLE */
-static int fillInUnixFile(
-  int h,                 /* Open file descriptor on file being opened */
-  int dirfd,
-  sqlite3_file *pId,     /* Write to the unixFile structure here */
-  const char *zFilename  /* Name of the file being opened */
-){
-  unixFile *pNew = (unixFile *)pId;
-  int rc;
 
-#ifdef FD_CLOEXEC
-  fcntl(h, F_SETFD, fcntl(h, F_GETFD, 0) | FD_CLOEXEC);
-#endif
-
-  enterMutex();
-  rc = findLockInfo(h, &pNew->pLock, &pNew->pOpen);
-  leaveMutex();
-  if( rc ){
-    if( dirfd>=0 ) close(dirfd);
-    close(h);
-    return rc;
+/*
+** Close a file & cleanup AFP specific locking context 
+*/
+static int afpClose(sqlite3_file *id) {
+  if( id ){
+    unixFile *pFile = (unixFile*)id;
+    afpUnlock(id, NO_LOCK);
+    unixEnterMutex();
+    if( pFile->pOpen && pFile->pOpen->nLock ){
+      /* If there are outstanding locks, do not actually close the file just
+      ** yet because that would clear those locks.  Instead, add the file
+      ** descriptor to pOpen->aPending.  It will be automatically closed when
+      ** the last lock is cleared.
+      */
+      setPendingFd(pFile);
+    }
+    releaseOpenCnt(pFile->pOpen);
+    sqlite3_free(pFile->lockingContext);
+    closeUnixFile(id);
+    unixLeaveMutex();
   }
-
-  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);
-  pNew->dirfd = -1;
-  pNew->h = h;
-  pNew->dirfd = dirfd;
-  SET_THREADID(pNew);
-
-  pNew->pMethod = &sqlite3UnixIoMethod;
-  OpenCounter(+1);
   return SQLITE_OK;
 }
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
 
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
 /*
-** Open a file descriptor to the directory containing file zFilename.
-** If successful, *pFd is set to the opened file descriptor and
-** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
-** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
-** value.
+** The code above is the AFP lock implementation.  The code is specific
+** to MacOSX and does not work on other unix platforms.  No alternative
+** is available.  If you don't compile for a mac, then the "unix-afp"
+** VFS is not available.
 **
-** If SQLITE_OK is returned, the caller is responsible for closing
-** the file descriptor *pFd using close().
-*/
-static int openDirectory(const char *zFilename, int *pFd){
-  int ii;
-  int fd = -1;
-  char zDirname[MAX_PATHNAME+1];
+********************* End of the AFP lock implementation **********************
+******************************************************************************/
 
-  sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
-  for(ii=strlen(zDirname); ii>=0 && zDirname[ii]!='/'; ii--);
-  if( ii>0 ){
-    zDirname[ii] = '\0';
-    fd = open(zDirname, O_RDONLY|O_BINARY, 0);
-    if( fd>=0 ){
-#ifdef FD_CLOEXEC
-      fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
-#endif
-      OSTRACE3("OPENDIR %-3d %s\n", fd, zDirname);
-    }
-  }
-  *pFd = fd;
-  return (fd>=0?SQLITE_OK:SQLITE_CANTOPEN);
-}
 
-/*
-** Open the file zPath.
-** 
-** Previously, the SQLite OS layer used three functions in place of this
-** one:
-**
-**     sqlite3OsOpenReadWrite();
-**     sqlite3OsOpenReadOnly();
-**     sqlite3OsOpenExclusive();
-**
-** These calls correspond to the following combinations of flags:
-**
-**     ReadWrite() ->     (READWRITE | CREATE)
-**     ReadOnly()  ->     (READONLY) 
-**     OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE)
+/******************************************************************************
+**************** Non-locking sqlite3_file methods *****************************
 **
-** The old OpenExclusive() accepted a boolean argument - "delFlag". If
-** true, the file was configured to be automatically deleted when the
-** file handle closed. To achieve the same effect using this new 
-** interface, add the DELETEONCLOSE flag to those specified above for 
-** OpenExclusive().
+** The next division contains implementations for all methods of the 
+** sqlite3_file object other than the locking methods.  The locking
+** methods were defined in divisions above (one locking method per
+** division).  Those methods that are common to all locking modes
+** are gather together into this division.
 */
-static int unixOpen(
-  sqlite3_vfs *pVfs, 
-  const char *zPath, 
-  sqlite3_file *pFile,
-  int flags,
-  int *pOutFlags
-){
-  int fd = 0;                    /* File descriptor returned by open() */
-  int dirfd = -1;                /* Directory file descriptor */
-  int oflags = 0;                /* Flags to pass to open() */
-  int eType = flags&0xFFFFFF00;  /* Type of file to open */
-
-  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
-  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
-  int isCreate     = (flags & SQLITE_OPEN_CREATE);
-  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
-  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
-
-  /* If creating a master or main-file journal, this function will open
-  ** a file-descriptor on the directory too. The first time unixSync()
-  ** is called the directory file descriptor will be fsync()ed and close()d.
-  */
-  int isOpenDirectory = (isCreate && 
-      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
-  );
-
-  /* Check the following statements are true: 
-  **
-  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
-  **   (b) if CREATE is set, then READWRITE must also be set, and
-  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
-  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
-  */
-  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
-  assert(isCreate==0 || isReadWrite);
-  assert(isExclusive==0 || isCreate);
-  assert(isDelete==0 || isCreate);
-
-
-  /* The main DB, main journal, and master journal are never automatically
-  ** deleted
-  */
-  assert( eType!=SQLITE_OPEN_MAIN_DB || !isDelete );
-  assert( eType!=SQLITE_OPEN_MAIN_JOURNAL || !isDelete );
-  assert( eType!=SQLITE_OPEN_MASTER_JOURNAL || !isDelete );
-
-  /* Assert that the upper layer has set one of the "file-type" flags. */
-  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
-       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
-       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB
-  );
-
-  if( isReadonly )  oflags |= O_RDONLY;
-  if( isReadWrite ) oflags |= O_RDWR;
-  if( isCreate )    oflags |= O_CREAT;
-  if( isExclusive ) oflags |= (O_EXCL|O_NOFOLLOW);
-  oflags |= (O_LARGEFILE|O_BINARY);
-
-  memset(pFile, 0, sizeof(unixFile));
-  fd = open(zPath, oflags, isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
-  if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
-    /* Failed to open the file for read/write access. Try read-only. */
-    flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
-    flags |= SQLITE_OPEN_READONLY;
-    return unixOpen(pVfs, zPath, pFile, flags, pOutFlags);
-  }
-  if( fd<0 ){
-    return SQLITE_CANTOPEN;
-  }
-  if( isDelete ){
-    unlink(zPath);
-  }
-  if( pOutFlags ){
-    *pOutFlags = flags;
-  }
-
-  assert(fd!=0);
-  if( isOpenDirectory ){
-    int rc = openDirectory(zPath, &dirfd);
-    if( rc!=SQLITE_OK ){
-      close(fd);
-      return rc;
-    }
-  }
-  return fillInUnixFile(fd, dirfd, pFile, zPath);
-}
 
 /*
-** Delete the file at zPath. If the dirSync argument is true, fsync()
-** the directory after deleting the file.
+** Seek to the offset passed as the second argument, then read cnt 
+** bytes into pBuf. Return the number of bytes actually read.
+**
+** NB:  If you define USE_PREAD or USE_PREAD64, then it might also
+** be necessary to define _XOPEN_SOURCE to be 500.  This varies from
+** one system to another.  Since SQLite does not define USE_PREAD
+** any any form by default, we will not attempt to define _XOPEN_SOURCE.
+** See tickets #2741 and #2681.
+**
+** To avoid stomping the errno value on a failed read the lastErrno value
+** is set before returning.
 */
-static int unixDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
-  int rc = SQLITE_OK;
-  SimulateIOError(return SQLITE_IOERR_DELETE);
-  unlink(zPath);
-  if( dirSync ){
-    int fd;
-    rc = openDirectory(zPath, &fd);
-    if( rc==SQLITE_OK ){
-      if( fsync(fd) ){
-        rc = SQLITE_IOERR_DIR_FSYNC;
-      }
-      close(fd);
+static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
+  int got;
+  i64 newOffset;
+  TIMER_START;
+#if defined(USE_PREAD)
+  got = pread(id->h, pBuf, cnt, offset);
+  SimulateIOError( got = -1 );
+#elif defined(USE_PREAD64)
+  got = pread64(id->h, pBuf, cnt, offset);
+  SimulateIOError( got = -1 );
+#else
+  newOffset = lseek(id->h, offset, SEEK_SET);
+  SimulateIOError( newOffset-- );
+  if( newOffset!=offset ){
+    if( newOffset == -1 ){
+      ((unixFile*)id)->lastErrno = errno;
+    }else{
+      ((unixFile*)id)->lastErrno = 0;			
     }
+    return -1;
   }
-  return rc;
+  got = read(id->h, pBuf, cnt);
+#endif
+  TIMER_END;
+  if( got<0 ){
+    ((unixFile*)id)->lastErrno = errno;
+  }
+  OSTRACE5("READ    %-3d %5d %7lld %llu\n", id->h, got, offset, TIMER_ELAPSED);
+  return got;
 }
 
 /*
-** Test the existance of or access permissions of file zPath. The
-** test performed depends on the value of flags:
-**
-**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
-**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
-**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
-**
-** Otherwise return 0.
+** Read data from a file into a buffer.  Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
 */
-static int unixAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
-  int amode = 0;
-  switch( flags ){
-    case SQLITE_ACCESS_EXISTS:
-      amode = F_OK;
-      break;
-    case SQLITE_ACCESS_READWRITE:
-      amode = W_OK|R_OK;
-      break;
-    case SQLITE_ACCESS_READ:
-      amode = R_OK;
-      break;
+static int unixRead(
+  sqlite3_file *id, 
+  void *pBuf, 
+  int amt,
+  sqlite3_int64 offset
+){
+  unixFile *pFile = (unixFile *)id;
+  int got;
+  assert( id );
 
-    default:
-      assert(!"Invalid flags argument");
+  /* If this is a database file (not a journal, master-journal or temp
+  ** file), the bytes in the locking range should never be read or written. */
+  assert( pFile->pUnused==0
+       || offset>=PENDING_BYTE+512
+       || offset+amt<=PENDING_BYTE 
+  );
+
+  got = seekAndRead(pFile, offset, pBuf, amt);
+  if( got==amt ){
+    return SQLITE_OK;
+  }else if( got<0 ){
+    /* lastErrno set by seekAndRead */
+    return SQLITE_IOERR_READ;
+  }else{
+    pFile->lastErrno = 0; /* not a system error */
+    /* Unread parts of the buffer must be zero-filled */
+    memset(&((char*)pBuf)[got], 0, amt-got);
+    return SQLITE_IOERR_SHORT_READ;
   }
-  return (access(zPath, amode)==0);
 }
 
 /*
-** Create a temporary file name in zBuf.  zBuf must be allocated
-** by the calling process and must be big enough to hold at least
-** pVfs->mxPathname bytes.
+** Seek to the offset in id->offset then read cnt bytes into pBuf.
+** Return the number of bytes actually read.  Update the offset.
+**
+** To avoid stomping the errno value on a failed write the lastErrno value
+** is set before returning.
 */
-static int unixGetTempname(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  static const char *azDirs[] = {
-     0,
-     "/var/tmp",
-     "/usr/tmp",
-     "/tmp",
-     ".",
-  };
-  static const unsigned char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  int i, j;
-  struct stat buf;
-  const char *zDir = ".";
-
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. 
-  */
-  SimulateIOError( return SQLITE_ERROR );
-
-  azDirs[0] = sqlite3_temp_directory;
-  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
-    if( azDirs[i]==0 ) continue;
-    if( stat(azDirs[i], &buf) ) continue;
-    if( !S_ISDIR(buf.st_mode) ) continue;
-    if( access(azDirs[i], 07) ) continue;
-    zDir = azDirs[i];
-    break;
+static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
+  int got;
+  i64 newOffset;
+  TIMER_START;
+#if defined(USE_PREAD)
+  got = pwrite(id->h, pBuf, cnt, offset);
+#elif defined(USE_PREAD64)
+  got = pwrite64(id->h, pBuf, cnt, offset);
+#else
+  newOffset = lseek(id->h, offset, SEEK_SET);
+  if( newOffset!=offset ){
+    if( newOffset == -1 ){
+      ((unixFile*)id)->lastErrno = errno;
+    }else{
+      ((unixFile*)id)->lastErrno = 0;			
+    }
+    return -1;
   }
-
-  /* Check that the output buffer is large enough for the temporary file 
-  ** name. If it is not, return SQLITE_ERROR.
-  */
-  if( (strlen(zDir) + strlen(SQLITE_TEMP_FILE_PREFIX) + 17) >= nBuf ){
-    return SQLITE_ERROR;
+  got = write(id->h, pBuf, cnt);
+#endif
+  TIMER_END;
+  if( got<0 ){
+    ((unixFile*)id)->lastErrno = errno;
   }
 
-  do{
-    assert( pVfs->mxPathname==MAX_PATHNAME );
-    sqlite3_snprintf(nBuf-17, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir);
-    j = strlen(zBuf);
-    sqlite3_randomness(15, &zBuf[j]);
-    for(i=0; i<15; i++, j++){
-      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
-    }
-    zBuf[j] = 0;
-  }while( access(zBuf,0)==0 );
-  return SQLITE_OK;
+  OSTRACE5("WRITE   %-3d %5d %7lld %llu\n", id->h, got, offset, TIMER_ELAPSED);
+  return got;
 }
 
 
 /*
-** Turn a relative pathname into a full pathname. The relative path
-** is stored as a nul-terminated string in the buffer pointed to by
-** zPath. 
-**
-** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
-** (in this case, MAX_PATHNAME bytes). The full-path is written to
-** this buffer before returning.
+** Write data from a buffer into a file.  Return SQLITE_OK on success
+** or some other error code on failure.
 */
-static int unixFullPathname(
-  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
-  const char *zPath,            /* Possibly relative input path */
-  int nOut,                     /* Size of output buffer in bytes */
-  char *zOut                    /* Output buffer */
+static int unixWrite(
+  sqlite3_file *id, 
+  const void *pBuf, 
+  int amt,
+  sqlite3_int64 offset 
 ){
+  unixFile *pFile = (unixFile*)id;
+  int wrote = 0;
+  assert( id );
+  assert( amt>0 );
 
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. This function could fail if, for example, the
-  ** current working directly has been unlinked.
-  */
-  SimulateIOError( return SQLITE_ERROR );
+  /* If this is a database file (not a journal, master-journal or temp
+  ** file), the bytes in the locking range should never be read or written. */
+  assert( pFile->pUnused==0
+       || offset>=PENDING_BYTE+512
+       || offset+amt<=PENDING_BYTE 
+  );
 
-  assert( pVfs->mxPathname==MAX_PATHNAME );
-  zOut[nOut-1] = '\0';
-  if( zPath[0]=='/' ){
-    sqlite3_snprintf(nOut, zOut, "%s", zPath);
-  }else{
-    int nCwd;
-    if( getcwd(zOut, nOut-1)==0 ){
-      return SQLITE_CANTOPEN;
+#ifndef NDEBUG
+  /* If we are doing a normal write to a database file (as opposed to
+  ** doing a hot-journal rollback or a write to some file other than a
+  ** normal database file) then record the fact that the database
+  ** has changed.  If the transaction counter is modified, record that
+  ** fact too.
+  */
+  if( pFile->inNormalWrite ){
+    pFile->dbUpdate = 1;  /* The database has been modified */
+    if( offset<=24 && offset+amt>=27 ){
+      int rc;
+      char oldCntr[4];
+      SimulateIOErrorBenign(1);
+      rc = seekAndRead(pFile, 24, oldCntr, 4);
+      SimulateIOErrorBenign(0);
+      if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
+        pFile->transCntrChng = 1;  /* The transaction counter has changed */
+      }
     }
-    nCwd = strlen(zOut);
-    sqlite3_snprintf(nOut-nCwd, &zOut[nCwd], "/%s", zPath);
   }
-  return SQLITE_OK;
+#endif
 
-#if 0
-  /*
-  ** Remove "/./" path elements and convert "/A/./" path elements
-  ** to just "/".
-  */
-  if( zFull ){
-    int i, j;
-    for(i=j=0; zFull[i]; i++){
-      if( zFull[i]=='/' ){
-        if( zFull[i+1]=='/' ) continue;
-        if( zFull[i+1]=='.' && zFull[i+2]=='/' ){
-          i += 1;
-          continue;
-        }
-        if( zFull[i+1]=='.' && zFull[i+2]=='.' && zFull[i+3]=='/' ){
-          while( j>0 && zFull[j-1]!='/' ){ j--; }
-          i += 3;
-          continue;
-        }
-      }
-      zFull[j++] = zFull[i];
+  while( amt>0 && (wrote = seekAndWrite(pFile, offset, pBuf, amt))>0 ){
+    amt -= wrote;
+    offset += wrote;
+    pBuf = &((char*)pBuf)[wrote];
+  }
+  SimulateIOError(( wrote=(-1), amt=1 ));
+  SimulateDiskfullError(( wrote=0, amt=1 ));
+  if( amt>0 ){
+    if( wrote<0 ){
+      /* lastErrno set by seekAndWrite */
+      return SQLITE_IOERR_WRITE;
+    }else{
+      pFile->lastErrno = 0; /* not a system error */
+      return SQLITE_FULL;
     }
-    zFull[j] = 0;
   }
-#endif
+  return SQLITE_OK;
 }
 
-
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
+#ifdef SQLITE_TEST
 /*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
+** Count the number of fullsyncs and normal syncs.  This is used to test
+** that syncs and fullsyncs are occurring at the right times.
 */
-#include <dlfcn.h>
-static void *unixDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
-  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
-}
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
 
 /*
-** SQLite calls this function immediately after a call to unixDlSym() or
-** unixDlOpen() fails (returns a null pointer). If a more detailed error
-** message is available, it is written to zBufOut. If no error message
-** is available, zBufOut is left unmodified and SQLite uses a default
-** error message.
+** We do not trust systems to provide a working fdatasync().  Some do.
+** Others do no.  To be safe, we will stick with the (slower) fsync().
+** If you know that your system does support fdatasync() correctly,
+** then simply compile with -Dfdatasync=fdatasync
 */
-static void unixDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
-  char *zErr;
-  enterMutex();
-  zErr = dlerror();
-  if( zErr ){
-    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
-  }
-  leaveMutex();
-}
-static void *unixDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
-  return dlsym(pHandle, zSymbol);
-}
-static void unixDlClose(sqlite3_vfs *pVfs, void *pHandle){
-  dlclose(pHandle);
-}
-#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
-  #define unixDlOpen  0
-  #define unixDlError 0
-  #define unixDlSym   0
-  #define unixDlClose 0
+#if !defined(fdatasync) && !defined(__linux__)
+# define fdatasync fsync
 #endif
 
 /*
-** Write nBuf bytes of random data to the supplied buffer zBuf.
+** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not
+** the F_FULLFSYNC macro is defined.  F_FULLFSYNC is currently
+** only available on Mac OS X.  But that could change.
 */
-static int unixRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-
-  assert(nBuf>=(sizeof(time_t)+sizeof(int)));
-
-  /* We have to initialize zBuf to prevent valgrind from reporting
-  ** errors.  The reports issued by valgrind are incorrect - we would
-  ** prefer that the randomness be increased by making use of the
-  ** uninitialized space in zBuf - but valgrind errors tend to worry
-  ** some users.  Rather than argue, it seems easier just to initialize
-  ** the whole array and silence valgrind, even if that means less randomness
-  ** in the random seed.
-  **
-  ** When testing, initializing zBuf[] to zero is all we do.  That means
-  ** that we always use the same random number sequence.  This makes the
-  ** tests repeatable.
-  */
-  memset(zBuf, 0, nBuf);
-#if !defined(SQLITE_TEST)
-  {
-    int pid, fd;
-    fd = open("/dev/urandom", O_RDONLY, 0);
-    if( fd<0 ){
-      time_t t;
-      time(&t);
-      memcpy(zBuf, &t, sizeof(t));
-#ifndef VXWORKS
-      pid = getpid();
+#ifdef F_FULLFSYNC
+# define HAVE_FULLFSYNC 1
 #else
-      pid = (int)taskIdCurrent();
-#endif
-      memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid));
-    }else{
-      read(fd, zBuf, nBuf);
-      close(fd);
-    }
-  }
+# define HAVE_FULLFSYNC 0
 #endif
-  return SQLITE_OK;
-}
 
 
 /*
-** Sleep for a little while.  Return the amount of time slept.
-** The argument is the number of microseconds we want to sleep.
-** The return value is the number of microseconds of sleep actually
-** requested from the underlying operating system, a number which
-** might be greater than or equal to the argument, but not less
-** than the argument.
+** The fsync() system call does not work as advertised on many
+** unix systems.  The following procedure is an attempt to make
+** it work better.
+**
+** The SQLITE_NO_SYNC macro disables all fsync()s.  This is useful
+** for testing when we want to run through the test suite quickly.
+** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
+** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
+** or power failure will likely corrupt the database file.
+**
+** SQLite sets the dataOnly flag if the size of the file is unchanged.
+** The idea behind dataOnly is that it should only write the file content
+** to disk, not the inode.  We only set dataOnly if the file size is 
+** unchanged since the file size is part of the inode.  However, 
+** Ted Ts'o tells us that fdatasync() will also write the inode if the
+** file size has changed.  The only real difference between fdatasync()
+** and fsync(), Ted tells us, is that fdatasync() will not flush the
+** inode if the mtime or owner or other inode attributes have changed.
+** We only care about the file size, not the other file attributes, so
+** as far as SQLite is concerned, an fdatasync() is always adequate.
+** So, we always use fdatasync() if it is available, regardless of
+** the value of the dataOnly flag.
 */
-static int unixSleep(sqlite3_vfs *pVfs, int microseconds){
-#if defined(HAVE_USLEEP) && HAVE_USLEEP
-  usleep(microseconds);
-  return microseconds;
+static int full_fsync(int fd, int fullSync, int dataOnly){
+  int rc;
+
+  /* The following "ifdef/elif/else/" block has the same structure as
+  ** the one below. It is replicated here solely to avoid cluttering 
+  ** up the real code with the UNUSED_PARAMETER() macros.
+  */
+#ifdef SQLITE_NO_SYNC
+  UNUSED_PARAMETER(fd);
+  UNUSED_PARAMETER(fullSync);
+  UNUSED_PARAMETER(dataOnly);
+#elif HAVE_FULLFSYNC
+  UNUSED_PARAMETER(dataOnly);
 #else
-  int seconds = (microseconds+999999)/1000000;
-  sleep(seconds);
-  return seconds*1000000;
+  UNUSED_PARAMETER(fullSync);
+  UNUSED_PARAMETER(dataOnly);
 #endif
-}
 
-/*
-** The following variable, if set to a non-zero value, becomes the result
-** returned from sqlite3OsCurrentTime().  This is used for testing.
-*/
+  /* Record the number of times that we do a normal fsync() and 
+  ** FULLSYNC.  This is used during testing to verify that this procedure
+  ** gets called with the correct arguments.
+  */
 #ifdef SQLITE_TEST
-SQLITE_API int sqlite3_current_time = 0;
+  if( fullSync ) sqlite3_fullsync_count++;
+  sqlite3_sync_count++;
 #endif
 
-/*
-** Find the current time (in Universal Coordinated Time).  Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0.  Return 1 if the time and date cannot be found.
-*/
-static int unixCurrentTime(sqlite3_vfs *pVfs, double *prNow){
-#ifdef NO_GETTOD
-  time_t t;
-  time(&t);
-  *prNow = t/86400.0 + 2440587.5;
-#else
-  struct timeval sNow;
-  gettimeofday(&sNow, 0);
-  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_usec/86400000000.0;
-#endif
-#ifdef SQLITE_TEST
-  if( sqlite3_current_time ){
-    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
+  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+  ** no-op
+  */
+#ifdef SQLITE_NO_SYNC
+  rc = SQLITE_OK;
+#elif HAVE_FULLFSYNC
+  if( fullSync ){
+    rc = fcntl(fd, F_FULLFSYNC, 0);
+  }else{
+    rc = 1;
   }
-#endif
-  return 0;
-}
+  /* If the FULLFSYNC failed, fall back to attempting an fsync().
+  ** It shouldn't be possible for fullfsync to fail on the local 
+  ** file system (on OSX), so failure indicates that FULLFSYNC
+  ** isn't supported for this file system. So, attempt an fsync 
+  ** and (for now) ignore the overhead of a superfluous fcntl call.  
+  ** It'd be better to detect fullfsync support once and avoid 
+  ** the fcntl call every time sync is called.
+  */
+  if( rc ) rc = fsync(fd);
 
-/*
-** Return a pointer to the sqlite3DefaultVfs structure.   We use
-** a function rather than give the structure global scope because
-** some compilers (MSVC) do not allow forward declarations of
-** initialized structures.
-*/
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
-  static sqlite3_vfs unixVfs = {
-    1,                  /* iVersion */
-    sizeof(unixFile),   /* szOsFile */
-    MAX_PATHNAME,       /* mxPathname */
-    0,                  /* pNext */
-    "unix",             /* zName */
-    0,                  /* pAppData */
-  
-    unixOpen,           /* xOpen */
-    unixDelete,         /* xDelete */
-    unixAccess,         /* xAccess */
-    unixGetTempname,    /* xGetTempName */
-    unixFullPathname,   /* xFullPathname */
-    unixDlOpen,         /* xDlOpen */
-    unixDlError,        /* xDlError */
-    unixDlSym,          /* xDlSym */
-    unixDlClose,        /* xDlClose */
-    unixRandomness,     /* xRandomness */
-    unixSleep,          /* xSleep */
-    unixCurrentTime     /* xCurrentTime */
-  };
-  
-  return &unixVfs;
+#else 
+  rc = fdatasync(fd);
+#if OS_VXWORKS
+  if( rc==-1 && errno==ENOTSUP ){
+    rc = fsync(fd);
+  }
+#endif /* OS_VXWORKS */
+#endif /* ifdef SQLITE_NO_SYNC elif HAVE_FULLFSYNC */
+
+  if( OS_VXWORKS && rc!= -1 ){
+    rc = 0;
+  }
+  return rc;
 }
- 
-#endif /* OS_UNIX */
 
-/************** End of os_unix.c *********************************************/
-/************** Begin file os_win.c ******************************************/
 /*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Make sure all writes to a particular file are committed to disk.
 **
-******************************************************************************
+** If dataOnly==0 then both the file itself and its metadata (file
+** size, access time, etc) are synced.  If dataOnly!=0 then only the
+** file data is synced.
 **
-** This file contains code that is specific to windows.
+** Under Unix, also make sure that the directory entry for the file
+** has been created by fsync-ing the directory that contains the file.
+** If we do not do this and we encounter a power failure, the directory
+** entry for the journal might not exist after we reboot.  The next
+** SQLite to access the file will not know that the journal exists (because
+** the directory entry for the journal was never created) and the transaction
+** will not roll back - possibly leading to database corruption.
 */
-#if OS_WIN               /* This file is used for windows only */
+static int unixSync(sqlite3_file *id, int flags){
+  int rc;
+  unixFile *pFile = (unixFile*)id;
 
+  int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
+  int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;
 
-/*
-** A Note About Memory Allocation:
-**
-** This driver uses malloc()/free() directly rather than going through
-** the SQLite-wrappers sqlite3_malloc()/sqlite3_free().  Those wrappers
-** are designed for use on embedded systems where memory is scarce and
-** malloc failures happen frequently.  Win32 does not typically run on
-** embedded systems, and when it does the developers normally have bigger
-** problems to worry about than running out of memory.  So there is not
-** a compelling need to use the wrappers.
-**
-** But there is a good reason to not use the wrappers.  If we use the
-** wrappers then we will get simulated malloc() failures within this
-** driver.  And that causes all kinds of problems for our tests.  We
-** could enhance SQLite to deal with simulated malloc failures within
-** the OS driver, but the code to deal with those failure would not
-** be exercised on Linux (which does not need to malloc() in the driver)
-** and so we would have difficulty writing coverage tests for that
-** code.  Better to leave the code out, we think.
-**
-** The point of this discussion is as follows:  When creating a new
-** OS layer for an embedded system, if you use this file as an example,
-** avoid the use of malloc()/free().  Those routines work ok on windows
-** desktops but not so well in embedded systems.
-*/
-
-#include <qconfig.h>
-
-#include <winbase.h>
+  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+      || (flags&0x0F)==SQLITE_SYNC_FULL
+  );
 
-#ifdef __CYGWIN__
-# include <sys/cygwin.h>
-#endif
+  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+  ** line is to test that doing so does not cause any problems.
+  */
+  SimulateDiskfullError( return SQLITE_FULL );
 
-/*
-** Macros used to determine whether or not to use threads.
-*/
-#ifndef QT_NO_THREAD
-# define SQLITE_W32_THREADS 1
+  assert( pFile );
+  OSTRACE2("SYNC    %-3d\n", pFile->h);
+  rc = full_fsync(pFile->h, isFullsync, isDataOnly);
+  SimulateIOError( rc=1 );
+  if( rc ){
+    pFile->lastErrno = errno;
+    return SQLITE_IOERR_FSYNC;
+  }
+  if( pFile->dirfd>=0 ){
+    int err;
+    OSTRACE4("DIRSYNC %-3d (have_fullfsync=%d fullsync=%d)\n", pFile->dirfd,
+            HAVE_FULLFSYNC, isFullsync);
+#ifndef SQLITE_DISABLE_DIRSYNC
+    /* The directory sync is only attempted if full_fsync is
+    ** turned off or unavailable.  If a full_fsync occurred above,
+    ** then the directory sync is superfluous.
+    */
+    if( (!HAVE_FULLFSYNC || !isFullsync) && full_fsync(pFile->dirfd,0,0) ){
+       /*
+       ** We have received multiple reports of fsync() returning
+       ** errors when applied to directories on certain file systems.
+       ** A failed directory sync is not a big deal.  So it seems
+       ** better to ignore the error.  Ticket #1657
+       */
+       /* pFile->lastErrno = errno; */
+       /* return SQLITE_IOERR; */
+    }
 #endif
+    err = close(pFile->dirfd); /* Only need to sync once, so close the */
+    if( err==0 ){              /* directory when we are done */
+      pFile->dirfd = -1;
+    }else{
+      pFile->lastErrno = errno;
+      rc = SQLITE_IOERR_DIR_CLOSE;
+    }
+  }
+  return rc;
+}
 
 /*
-** Include code that is common to all os_*.c files
-*/
-/************** Include os_common.h in the middle of os_win.c ****************/
-/************** Begin file os_common.h ***************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains macros and a little bit of code that is common to
-** all of the platform-specific files (os_*.c) and is #included into those
-** files.
-**
-** This file should be #included by the os_*.c files only.  It is not a
-** general purpose header file.
+** Truncate an open file to a specified size
 */
+static int unixTruncate(sqlite3_file *id, i64 nByte){
+  int rc;
+  assert( id );
+  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
+  rc = ftruncate(((unixFile*)id)->h, (off_t)nByte);
+  if( rc ){
+    ((unixFile*)id)->lastErrno = errno;
+    return SQLITE_IOERR_TRUNCATE;
+  }else{
+    return SQLITE_OK;
+  }
+}
 
 /*
-** At least two bugs have slipped in because we changed the MEMORY_DEBUG
-** macro to SQLITE_DEBUG and some older makefiles have not yet made the
-** switch.  The following code should catch this problem at compile-time.
+** Determine the current size of a file in bytes
 */
-#ifdef MEMORY_DEBUG
-# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
-#endif
-
-
-/*
- * When testing, this global variable stores the location of the
- * pending-byte in the database file.
- */
-#ifdef SQLITE_TEST
-SQLITE_API unsigned int sqlite3_pending_byte = 0x40000000;
-#endif
+static int unixFileSize(sqlite3_file *id, i64 *pSize){
+  int rc;
+  struct stat buf;
+  assert( id );
+  rc = fstat(((unixFile*)id)->h, &buf);
+  SimulateIOError( rc=1 );
+  if( rc!=0 ){
+    ((unixFile*)id)->lastErrno = errno;
+    return SQLITE_IOERR_FSTAT;
+  }
+  *pSize = buf.st_size;
 
-#ifdef SQLITE_DEBUG
-SQLITE_PRIVATE int sqlite3OSTrace = 0;
-#define OSTRACE1(X)         if( sqlite3OSTrace ) sqlite3DebugPrintf(X)
-#define OSTRACE2(X,Y)       if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y)
-#define OSTRACE3(X,Y,Z)     if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z)
-#define OSTRACE4(X,Y,Z,A)   if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A)
-#define OSTRACE5(X,Y,Z,A,B) if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A,B)
-#define OSTRACE6(X,Y,Z,A,B,C) \
-    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C)
-#define OSTRACE7(X,Y,Z,A,B,C,D) \
-    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C,D)
-#else
-#define OSTRACE1(X)
-#define OSTRACE2(X,Y)
-#define OSTRACE3(X,Y,Z)
-#define OSTRACE4(X,Y,Z,A)
-#define OSTRACE5(X,Y,Z,A,B)
-#define OSTRACE6(X,Y,Z,A,B,C)
-#define OSTRACE7(X,Y,Z,A,B,C,D)
-#endif
+  /* When opening a zero-size database, the findLockInfo() procedure
+  ** writes a single byte into that file in order to work around a bug
+  ** in the OS-X msdos filesystem.  In order to avoid problems with upper
+  ** layers, we need to report this file size as zero even though it is
+  ** really 1.   Ticket #3260.
+  */
+  if( *pSize==1 ) *pSize = 0;
 
-/*
-** Macros for performance tracing.  Normally turned off.  Only works
-** on i486 hardware.
-*/
-#ifdef SQLITE_PERFORMANCE_TRACE
-__inline__ unsigned long long int hwtime(void){
-  unsigned long long int x;
-  __asm__("rdtsc\n\t"
-          "mov %%edx, %%ecx\n\t"
-          :"=A" (x));
-  return x;
-}
-static unsigned long long int g_start;
-static unsigned int elapse;
-#define TIMER_START       g_start=hwtime()
-#define TIMER_END         elapse=hwtime()-g_start
-#define TIMER_ELAPSED     elapse
-#else
-#define TIMER_START
-#define TIMER_END
-#define TIMER_ELAPSED     0
-#endif
 
-/*
-** If we compile with the SQLITE_TEST macro set, then the following block
-** of code will give us the ability to simulate a disk I/O error.  This
-** is used for testing the I/O recovery logic.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
-SQLITE_API int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
-SQLITE_API int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
-SQLITE_API int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
-SQLITE_API int sqlite3_io_error_benign = 0;         /* True if errors are benign */
-SQLITE_API int sqlite3_diskfull_pending = 0;
-SQLITE_API int sqlite3_diskfull = 0;
-#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
-#define SimulateIOError(CODE)  \
-  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
-       || sqlite3_io_error_pending-- == 1 )  \
-              { local_ioerr(); CODE; }
-static void local_ioerr(){
-  IOTRACE(("IOERR\n"));
-  sqlite3_io_error_hit++;
-  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+  return SQLITE_OK;
 }
-#define SimulateDiskfullError(CODE) \
-   if( sqlite3_diskfull_pending ){ \
-     if( sqlite3_diskfull_pending == 1 ){ \
-       local_ioerr(); \
-       sqlite3_diskfull = 1; \
-       sqlite3_io_error_hit = 1; \
-       CODE; \
-     }else{ \
-       sqlite3_diskfull_pending--; \
-     } \
-   }
-#else
-#define SimulateIOErrorBenign(X)
-#define SimulateIOError(A)
-#define SimulateDiskfullError(A)
-#endif
 
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
 /*
-** When testing, keep a count of the number of open files.
+** Handler for proxy-locking file-control verbs.  Defined below in the
+** proxying locking division.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_open_file_count = 0;
-#define OpenCounter(X)  sqlite3_open_file_count+=(X)
-#else
-#define OpenCounter(X)
+static int proxyFileControl(sqlite3_file*,int,void*);
 #endif
 
-/************** End of os_common.h *******************************************/
-/************** Continuing where we left off in os_win.c *********************/
 
 /*
-** Determine if we are dealing with WindowsCE - which has a much
-** reduced API.
+** Information and control of an open file handle.
 */
-#if defined(_WIN32_WCE)
-# define OS_WINCE 1
-# define AreFileApisANSI() 1
-#else
-# define OS_WINCE 0
+static int unixFileControl(sqlite3_file *id, int op, void *pArg){
+  switch( op ){
+    case SQLITE_FCNTL_LOCKSTATE: {
+      *(int*)pArg = ((unixFile*)id)->locktype;
+      return SQLITE_OK;
+    }
+    case SQLITE_LAST_ERRNO: {
+      *(int*)pArg = ((unixFile*)id)->lastErrno;
+      return SQLITE_OK;
+    }
+#ifndef NDEBUG
+    /* The pager calls this method to signal that it has done
+    ** a rollback and that the database is therefore unchanged and
+    ** it hence it is OK for the transaction change counter to be
+    ** unchanged.
+    */
+    case SQLITE_FCNTL_DB_UNCHANGED: {
+      ((unixFile*)id)->dbUpdate = 0;
+      return SQLITE_OK;
+    }
 #endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+    case SQLITE_SET_LOCKPROXYFILE:
+    case SQLITE_GET_LOCKPROXYFILE: {
+      return proxyFileControl(id,op,pArg);
+    }
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__) */
+  }
+  return SQLITE_ERROR;
+}
 
 /*
-** WinCE lacks native support for file locking so we have to fake it
-** with some code of our own.
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
+**
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
 */
-#if OS_WINCE
-typedef struct winceLock {
-  int nReaders;       /* Number of reader locks obtained */
-  BOOL bPending;      /* Indicates a pending lock has been obtained */
-  BOOL bReserved;     /* Indicates a reserved lock has been obtained */
-  BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
-} winceLock;
-#endif
+static int unixSectorSize(sqlite3_file *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  return SQLITE_DEFAULT_SECTOR_SIZE;
+}
 
 /*
-** The winFile structure is a subclass of sqlite3_file* specific to the win32
-** portability layer.
+** Return the device characteristics for the file. This is always 0 for unix.
 */
-typedef struct winFile winFile;
-struct winFile {
-  const sqlite3_io_methods *pMethod;/* Must be first */
-  HANDLE h;               /* Handle for accessing the file */
-  unsigned char locktype; /* Type of lock currently held on this file */
-  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
-#if OS_WINCE
-  WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
-  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
-  HANDLE hShared;         /* Shared memory segment used for locking */
-  winceLock local;        /* Locks obtained by this instance of winFile */
-  winceLock *shared;      /* Global shared lock memory for the file  */
-#endif
-};
-
+static int unixDeviceCharacteristics(sqlite3_file *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  return 0;
+}
 
 /*
-** The following variable is (normally) set once and never changes
-** thereafter.  It records whether the operating system is Win95
-** or WinNT.
-**
-** 0:   Operating system unknown.
-** 1:   Operating system is Win95.
-** 2:   Operating system is WinNT.
+** Here ends the implementation of all sqlite3_file methods.
 **
-** In order to facilitate testing on a WinNT system, the test fixture
-** can manually set this value to 1 to emulate Win98 behavior.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_os_type = 0;
-#else
-static int sqlite3_os_type = 0;
-#endif
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
 
 /*
-** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
-** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
+** This division contains definitions of sqlite3_io_methods objects that
+** implement various file locking strategies.  It also contains definitions
+** of "finder" functions.  A finder-function is used to locate the appropriate
+** sqlite3_io_methods object for a particular database file.  The pAppData
+** field of the sqlite3_vfs VFS objects are initialized to be pointers to
+** the correct finder-function for that VFS.
+**
+** Most finder functions return a pointer to a fixed sqlite3_io_methods
+** object.  The only interesting finder-function is autolockIoFinder, which
+** looks at the filesystem type and tries to guess the best locking
+** strategy from that.
+**
+** For finder-funtion F, two objects are created:
+**
+**    (1) The real finder-function named "FImpt()".
+**
+**    (2) A constant pointer to this function named just "F".
+**
+**
+** A pointer to the F pointer is used as the pAppData value for VFS
+** objects.  We have to do this instead of letting pAppData point
+** directly at the finder-function since C90 rules prevent a void*
+** from be cast into a function pointer.
+**
+**
+** Each instance of this macro generates two objects:
+**
+**   *  A constant sqlite3_io_methods object call METHOD that has locking
+**      methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
+**
+**   *  An I/O method finder function called FINDER that returns a pointer
+**      to the METHOD object in the previous bullet.
+*/
+#define IOMETHODS(FINDER, METHOD, CLOSE, LOCK, UNLOCK, CKLOCK)               \
+static const sqlite3_io_methods METHOD = {                                   \
+   1,                          /* iVersion */                                \
+   CLOSE,                      /* xClose */                                  \
+   unixRead,                   /* xRead */                                   \
+   unixWrite,                  /* xWrite */                                  \
+   unixTruncate,               /* xTruncate */                               \
+   unixSync,                   /* xSync */                                   \
+   unixFileSize,               /* xFileSize */                               \
+   LOCK,                       /* xLock */                                   \
+   UNLOCK,                     /* xUnlock */                                 \
+   CKLOCK,                     /* xCheckReservedLock */                      \
+   unixFileControl,            /* xFileControl */                            \
+   unixSectorSize,             /* xSectorSize */                             \
+   unixDeviceCharacteristics   /* xDeviceCapabilities */                     \
+};                                                                           \
+static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
+  UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
+  return &METHOD;                                                            \
+}                                                                            \
+static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p)    \
+    = FINDER##Impl;
+
+/*
+** Here are all of the sqlite3_io_methods objects for each of the
+** locking strategies.  Functions that return pointers to these methods
+** are also created.
+*/
+IOMETHODS(
+  posixIoFinder,            /* Finder function name */
+  posixIoMethods,           /* sqlite3_io_methods object name */
+  unixClose,                /* xClose method */
+  unixLock,                 /* xLock method */
+  unixUnlock,               /* xUnlock method */
+  unixCheckReservedLock     /* xCheckReservedLock method */
+)
+IOMETHODS(
+  nolockIoFinder,           /* Finder function name */
+  nolockIoMethods,          /* sqlite3_io_methods object name */
+  nolockClose,              /* xClose method */
+  nolockLock,               /* xLock method */
+  nolockUnlock,             /* xUnlock method */
+  nolockCheckReservedLock   /* xCheckReservedLock method */
+)
+IOMETHODS(
+  dotlockIoFinder,          /* Finder function name */
+  dotlockIoMethods,         /* sqlite3_io_methods object name */
+  dotlockClose,             /* xClose method */
+  dotlockLock,              /* xLock method */
+  dotlockUnlock,            /* xUnlock method */
+  dotlockCheckReservedLock  /* xCheckReservedLock method */
+)
+
+#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
+IOMETHODS(
+  flockIoFinder,            /* Finder function name */
+  flockIoMethods,           /* sqlite3_io_methods object name */
+  flockClose,               /* xClose method */
+  flockLock,                /* xLock method */
+  flockUnlock,              /* xUnlock method */
+  flockCheckReservedLock    /* xCheckReservedLock method */
+)
+#endif
+
+#if OS_VXWORKS
+IOMETHODS(
+  semIoFinder,              /* Finder function name */
+  semIoMethods,             /* sqlite3_io_methods object name */
+  semClose,                 /* xClose method */
+  semLock,                  /* xLock method */
+  semUnlock,                /* xUnlock method */
+  semCheckReservedLock      /* xCheckReservedLock method */
+)
+#endif
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+  afpIoFinder,              /* Finder function name */
+  afpIoMethods,             /* sqlite3_io_methods object name */
+  afpClose,                 /* xClose method */
+  afpLock,                  /* xLock method */
+  afpUnlock,                /* xUnlock method */
+  afpCheckReservedLock      /* xCheckReservedLock method */
+)
+#endif
+
+/*
+** The "Whole File Locking" finder returns the same set of methods as
+** the posix locking finder.  But it also sets the SQLITE_WHOLE_FILE_LOCKING
+** flag to force the posix advisory locks to cover the whole file instead
+** of just a small span of bytes near the 1GiB boundary.  Whole File Locking
+** is useful on NFS-mounted files since it helps NFS to maintain cache
+** coherency.  But it is a detriment to other filesystems since it runs
+** slower.
+*/
+static const sqlite3_io_methods *posixWflIoFinderImpl(const char*z, unixFile*p){
+  UNUSED_PARAMETER(z);
+  p->fileFlags = SQLITE_WHOLE_FILE_LOCKING;
+  return &posixIoMethods;
+}
+static const sqlite3_io_methods 
+  *(*const posixWflIoFinder)(const char*,unixFile *p) = posixWflIoFinderImpl;
+
+/*
+** The proxy locking method is a "super-method" in the sense that it
+** opens secondary file descriptors for the conch and lock files and
+** it uses proxy, dot-file, AFP, and flock() locking methods on those
+** secondary files.  For this reason, the division that implements
+** proxy locking is located much further down in the file.  But we need
+** to go ahead and define the sqlite3_io_methods and finder function
+** for proxy locking here.  So we forward declare the I/O methods.
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+static int proxyClose(sqlite3_file*);
+static int proxyLock(sqlite3_file*, int);
+static int proxyUnlock(sqlite3_file*, int);
+static int proxyCheckReservedLock(sqlite3_file*, int*);
+IOMETHODS(
+  proxyIoFinder,            /* Finder function name */
+  proxyIoMethods,           /* sqlite3_io_methods object name */
+  proxyClose,               /* xClose method */
+  proxyLock,                /* xLock method */
+  proxyUnlock,              /* xUnlock method */
+  proxyCheckReservedLock    /* xCheckReservedLock method */
+)
+#endif
+
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/* 
+** This "finder" function attempts to determine the best locking strategy 
+** for the database file "filePath".  It then returns the sqlite3_io_methods
+** object that implements that strategy.
 **
-** Here is an interesting observation:  Win95, Win98, and WinME lack
-** the LockFileEx() API.  But we can still statically link against that
-** API as long as we don't call it win running Win95/98/ME.  A call to
-** this routine is used to determine if the host is Win95/98/ME or
-** WinNT/2K/XP so that we will know whether or not we can safely call
-** the LockFileEx() API.
+** This is for MacOSX only.
 */
-#if OS_WINCE
-# define isNT()  (1)
+static const sqlite3_io_methods *autolockIoFinderImpl(
+  const char *filePath,    /* name of the database file */
+  unixFile *pNew           /* open file object for the database file */
+){
+  static const struct Mapping {
+    const char *zFilesystem;              /* Filesystem type name */
+    const sqlite3_io_methods *pMethods;   /* Appropriate locking method */
+  } aMap[] = {
+    { "hfs",    &posixIoMethods },
+    { "ufs",    &posixIoMethods },
+    { "afpfs",  &afpIoMethods },
+#ifdef SQLITE_ENABLE_AFP_LOCKING_SMB
+    { "smbfs",  &afpIoMethods },
 #else
-  static int isNT(void){
-    if( sqlite3_os_type==0 ){
-      OSVERSIONINFO sInfo;
-      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
-      GetVersionEx(&sInfo);
-      sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
+    { "smbfs",  &flockIoMethods },
+#endif
+    { "webdav", &nolockIoMethods },
+    { 0, 0 }
+  };
+  int i;
+  struct statfs fsInfo;
+  struct flock lockInfo;
+
+  if( !filePath ){
+    /* If filePath==NULL that means we are dealing with a transient file
+    ** that does not need to be locked. */
+    return &nolockIoMethods;
+  }
+  if( statfs(filePath, &fsInfo) != -1 ){
+    if( fsInfo.f_flags & MNT_RDONLY ){
+      return &nolockIoMethods;
+    }
+    for(i=0; aMap[i].zFilesystem; i++){
+      if( strcmp(fsInfo.f_fstypename, aMap[i].zFilesystem)==0 ){
+        return aMap[i].pMethods;
+      }
     }
-    return sqlite3_os_type==2;
   }
-#endif /* OS_WINCE */
 
-/*
-** Convert a UTF-8 string to microsoft unicode (UTF-16?). 
+  /* Default case. Handles, amongst others, "nfs".
+  ** Test byte-range lock using fcntl(). If the call succeeds, 
+  ** assume that the file-system supports POSIX style locks. 
+  */
+  lockInfo.l_len = 1;
+  lockInfo.l_start = 0;
+  lockInfo.l_whence = SEEK_SET;
+  lockInfo.l_type = F_RDLCK;
+  if( fcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+    pNew->fileFlags = SQLITE_WHOLE_FILE_LOCKING;
+    return &posixIoMethods;
+  }else{
+    return &dotlockIoMethods;
+  }
+}
+static const sqlite3_io_methods 
+  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+
+#if OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE
+/* 
+** This "finder" function attempts to determine the best locking strategy 
+** for the database file "filePath".  It then returns the sqlite3_io_methods
+** object that implements that strategy.
 **
-** Space to hold the returned string is obtained from malloc.
+** This is for VXWorks only.
 */
-static WCHAR *utf8ToUnicode(const char *zFilename){
-  int nChar;
-  WCHAR *zWideFilename;
+static const sqlite3_io_methods *autolockIoFinderImpl(
+  const char *filePath,    /* name of the database file */
+  unixFile *pNew           /* the open file object */
+){
+  struct flock lockInfo;
 
-  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
-  zWideFilename = malloc( nChar*sizeof(zWideFilename[0]) );
-  if( zWideFilename==0 ){
-    return 0;
+  if( !filePath ){
+    /* If filePath==NULL that means we are dealing with a transient file
+    ** that does not need to be locked. */
+    return &nolockIoMethods;
   }
-  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar);
-  if( nChar==0 ){
-    free(zWideFilename);
-    zWideFilename = 0;
+
+  /* Test if fcntl() is supported and use POSIX style locks.
+  ** Otherwise fall back to the named semaphore method.
+  */
+  lockInfo.l_len = 1;
+  lockInfo.l_start = 0;
+  lockInfo.l_whence = SEEK_SET;
+  lockInfo.l_type = F_RDLCK;
+  if( fcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+    return &posixIoMethods;
+  }else{
+    return &semIoMethods;
   }
-  return zWideFilename;
 }
+static const sqlite3_io_methods 
+  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
+
+#endif /* OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE */
 
 /*
-** Convert microsoft unicode to UTF-8.  Space to hold the returned string is
-** obtained from malloc().
+** An abstract type for a pointer to a IO method finder function:
 */
-static char *unicodeToUtf8(const WCHAR *zWideFilename){
-  int nByte;
-  char *zFilename;
+typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
 
-  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
-  zFilename = malloc( nByte );
-  if( zFilename==0 ){
-    return 0;
-  }
-  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
-                              0, 0);
-  if( nByte == 0 ){
-    free(zFilename);
-    zFilename = 0;
-  }
-  return zFilename;
-}
+
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
+**
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
 
 /*
-** Convert an ansi string to microsoft unicode, based on the
-** current codepage settings for file apis.
-** 
-** Space to hold the returned string is obtained
-** from malloc.
+** Initialize the contents of the unixFile structure pointed to by pId.
 */
-static WCHAR *mbcsToUnicode(const char *zFilename){
-  int nByte;
-  WCHAR *zMbcsFilename;
-  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;
+static int fillInUnixFile(
+  sqlite3_vfs *pVfs,      /* Pointer to vfs object */
+  int h,                  /* Open file descriptor of file being opened */
+  int dirfd,              /* Directory file descriptor */
+  sqlite3_file *pId,      /* Write to the unixFile structure here */
+  const char *zFilename,  /* Name of the file being opened */
+  int noLock,             /* Omit locking if true */
+  int isDelete            /* Delete on close if true */
+){
+  const sqlite3_io_methods *pLockingStyle;
+  unixFile *pNew = (unixFile *)pId;
+  int rc = SQLITE_OK;
 
-  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR);
-  zMbcsFilename = malloc( nByte*sizeof(zMbcsFilename[0]) );
-  if( zMbcsFilename==0 ){
-    return 0;
-  }
-  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte);
-  if( nByte==0 ){
-    free(zMbcsFilename);
-    zMbcsFilename = 0;
+  assert( pNew->pLock==NULL );
+  assert( pNew->pOpen==NULL );
+
+  /* Parameter isDelete is only used on vxworks. Express this explicitly 
+  ** here to prevent compiler warnings about unused parameters.
+  */
+  UNUSED_PARAMETER(isDelete);
+
+  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);    
+  pNew->h = h;
+  pNew->dirfd = dirfd;
+  SET_THREADID(pNew);
+  pNew->fileFlags = 0;
+
+#if OS_VXWORKS
+  pNew->pId = vxworksFindFileId(zFilename);
+  if( pNew->pId==0 ){
+    noLock = 1;
+    rc = SQLITE_NOMEM;
   }
-  return zMbcsFilename;
-}
+#endif
 
-/*
-** Convert microsoft unicode to multibyte character string, based on the
-** user's Ansi codepage.
-**
-** Space to hold the returned string is obtained from
-** malloc().
-*/
-static char *unicodeToMbcs(const WCHAR *zWideFilename){
-  int nByte;
-  char *zFilename;
-  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;
+  if( noLock ){
+    pLockingStyle = &nolockIoMethods;
+  }else{
+    pLockingStyle = (**(finder_type*)pVfs->pAppData)(zFilename, pNew);
+#if SQLITE_ENABLE_LOCKING_STYLE
+    /* Cache zFilename in the locking context (AFP and dotlock override) for
+    ** proxyLock activation is possible (remote proxy is based on db name)
+    ** zFilename remains valid until file is closed, to support */
+    pNew->lockingContext = (void*)zFilename;
+#endif
+  }
 
-  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
-  zFilename = malloc( nByte );
-  if( zFilename==0 ){
-    return 0;
+  if( pLockingStyle == &posixIoMethods ){
+    unixEnterMutex();
+    rc = findLockInfo(pNew, &pNew->pLock, &pNew->pOpen);
+    if( rc!=SQLITE_OK ){
+      /* If an error occured in findLockInfo(), close the file descriptor
+      ** immediately, before releasing the mutex. findLockInfo() may fail
+      ** in two scenarios:
+      **
+      **   (a) A call to fstat() failed.
+      **   (b) A malloc failed.
+      **
+      ** Scenario (b) may only occur if the process is holding no other
+      ** file descriptors open on the same file. If there were other file
+      ** descriptors on this file, then no malloc would be required by
+      ** findLockInfo(). If this is the case, it is quite safe to close
+      ** handle h - as it is guaranteed that no posix locks will be released
+      ** by doing so.
+      **
+      ** If scenario (a) caused the error then things are not so safe. The
+      ** implicit assumption here is that if fstat() fails, things are in
+      ** such bad shape that dropping a lock or two doesn't matter much.
+      */
+      close(h);
+      h = -1;
+    }
+    unixLeaveMutex();
   }
-  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte,
-                              0, 0);
-  if( nByte == 0 ){
-    free(zFilename);
-    zFilename = 0;
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+  else if( pLockingStyle == &afpIoMethods ){
+    /* AFP locking uses the file path so it needs to be included in
+    ** the afpLockingContext.
+    */
+    afpLockingContext *pCtx;
+    pNew->lockingContext = pCtx = sqlite3_malloc( sizeof(*pCtx) );
+    if( pCtx==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      /* NB: zFilename exists and remains valid until the file is closed
+      ** according to requirement F11141.  So we do not need to make a
+      ** copy of the filename. */
+      pCtx->dbPath = zFilename;
+      srandomdev();
+      unixEnterMutex();
+      rc = findLockInfo(pNew, NULL, &pNew->pOpen);
+      unixLeaveMutex();        
+    }
   }
-  return zFilename;
-}
+#endif
 
-/*
-** Convert multibyte character string to UTF-8.  Space to hold the
-** returned string is obtained from malloc().
-*/
-static char *mbcsToUtf8(const char *zFilename){
-  char *zFilenameUtf8;
-  WCHAR *zTmpWide;
+  else if( pLockingStyle == &dotlockIoMethods ){
+    /* Dotfile locking uses the file path so it needs to be included in
+    ** the dotlockLockingContext 
+    */
+    char *zLockFile;
+    int nFilename;
+    nFilename = (int)strlen(zFilename) + 6;
+    zLockFile = (char *)sqlite3_malloc(nFilename);
+    if( zLockFile==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      sqlite3_snprintf(nFilename, zLockFile, "%s" DOTLOCK_SUFFIX, zFilename);
+    }
+    pNew->lockingContext = zLockFile;
+  }
 
-  zTmpWide = mbcsToUnicode(zFilename);
-  if( zTmpWide==0 ){
-    return 0;
+#if OS_VXWORKS
+  else if( pLockingStyle == &semIoMethods ){
+    /* Named semaphore locking uses the file path so it needs to be
+    ** included in the semLockingContext
+    */
+    unixEnterMutex();
+    rc = findLockInfo(pNew, &pNew->pLock, &pNew->pOpen);
+    if( (rc==SQLITE_OK) && (pNew->pOpen->pSem==NULL) ){
+      char *zSemName = pNew->pOpen->aSemName;
+      int n;
+      sqlite3_snprintf(MAX_PATHNAME, zSemName, "/%s.sem",
+                       pNew->pId->zCanonicalName);
+      for( n=1; zSemName[n]; n++ )
+        if( zSemName[n]=='/' ) zSemName[n] = '_';
+      pNew->pOpen->pSem = sem_open(zSemName, O_CREAT, 0666, 1);
+      if( pNew->pOpen->pSem == SEM_FAILED ){
+        rc = SQLITE_NOMEM;
+        pNew->pOpen->aSemName[0] = '\0';
+      }
+    }
+    unixLeaveMutex();
   }
-  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
-  free(zTmpWide);
-  return zFilenameUtf8;
+#endif
+  
+  pNew->lastErrno = 0;
+#if OS_VXWORKS
+  if( rc!=SQLITE_OK ){
+    unlink(zFilename);
+    isDelete = 0;
+  }
+  pNew->isDelete = isDelete;
+#endif
+  if( rc!=SQLITE_OK ){
+    if( dirfd>=0 ) close(dirfd); /* silent leak if fail, already in error */
+    if( h>=0 ) close(h);
+  }else{
+    pNew->pMethod = pLockingStyle;
+    OpenCounter(+1);
+  }
+  return rc;
 }
 
 /*
-** Convert UTF-8 to multibyte character string.  Space to hold the 
-** returned string is obtained from malloc().
+** Open a file descriptor to the directory containing file zFilename.
+** If successful, *pFd is set to the opened file descriptor and
+** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
+** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
+** value.
+**
+** If SQLITE_OK is returned, the caller is responsible for closing
+** the file descriptor *pFd using close().
 */
-static char *utf8ToMbcs(const char *zFilename){
-  char *zFilenameMbcs;
-  WCHAR *zTmpWide;
+static int openDirectory(const char *zFilename, int *pFd){
+  int ii;
+  int fd = -1;
+  char zDirname[MAX_PATHNAME+1];
 
-  zTmpWide = utf8ToUnicode(zFilename);
-  if( zTmpWide==0 ){
-    return 0;
+  sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
+  for(ii=(int)strlen(zDirname); ii>1 && zDirname[ii]!='/'; ii--);
+  if( ii>0 ){
+    zDirname[ii] = '\0';
+    fd = open(zDirname, O_RDONLY|O_BINARY, 0);
+    if( fd>=0 ){
+#ifdef FD_CLOEXEC
+      fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
+#endif
+      OSTRACE3("OPENDIR %-3d %s\n", fd, zDirname);
+    }
   }
-  zFilenameMbcs = unicodeToMbcs(zTmpWide);
-  free(zTmpWide);
-  return zFilenameMbcs;
+  *pFd = fd;
+  return (fd>=0?SQLITE_OK:SQLITE_CANTOPEN);
 }
 
-#if OS_WINCE
-/*************************************************************************
-** This section contains code for WinCE only.
-*/
 /*
-** WindowsCE does not have a localtime() function.  So create a
-** substitute.
+** Create a temporary file name in zBuf.  zBuf must be allocated
+** by the calling process and must be big enough to hold at least
+** pVfs->mxPathname bytes.
 */
-static struct tm *__cdecl localtime(const time_t *t)
-{
-  static struct tm y;
-  FILETIME uTm, lTm;
-  SYSTEMTIME pTm;
-  sqlite3_int64 t64;
-  t64 = *t;
-  t64 = (t64 + 11644473600)*10000000;
-  uTm.dwLowDateTime = t64 & 0xFFFFFFFF;
-  uTm.dwHighDateTime= t64 >> 32;
-  FileTimeToLocalFileTime(&uTm,&lTm);
-  FileTimeToSystemTime(&lTm,&pTm);
-  y.tm_year = pTm.wYear - 1900;
-  y.tm_mon = pTm.wMonth - 1;
-  y.tm_wday = pTm.wDayOfWeek;
-  y.tm_mday = pTm.wDay;
-  y.tm_hour = pTm.wHour;
-  y.tm_min = pTm.wMinute;
-  y.tm_sec = pTm.wSecond;
-  return &y;
-}
+static int getTempname(int nBuf, char *zBuf){
+  static const char *azDirs[] = {
+     0,
+     0,
+     "/var/tmp",
+     "/usr/tmp",
+     "/tmp",
+     ".",
+  };
+  static const unsigned char zChars[] =
+    "abcdefghijklmnopqrstuvwxyz"
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "0123456789";
+  unsigned int i, j;
+  struct stat buf;
+  const char *zDir = ".";
 
-/* This will never be called, but defined to make the code compile */
-#define GetTempPathA(a,b)
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. 
+  */
+  SimulateIOError( return SQLITE_IOERR );
 
-#define LockFile(a,b,c,d,e)       winceLockFile(&a, b, c, d, e)
-#define UnlockFile(a,b,c,d,e)     winceUnlockFile(&a, b, c, d, e)
-#define LockFileEx(a,b,c,d,e,f)   winceLockFileEx(&a, b, c, d, e, f)
+  azDirs[0] = sqlite3_temp_directory;
+  if (NULL == azDirs[1]) {
+    azDirs[1] = getenv("TMPDIR");
+  }
+  
+  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
+    if( azDirs[i]==0 ) continue;
+    if( stat(azDirs[i], &buf) ) continue;
+    if( !S_ISDIR(buf.st_mode) ) continue;
+    if( access(azDirs[i], 07) ) continue;
+    zDir = azDirs[i];
+    break;
+  }
 
-#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-offsetof(winFile,h)]
+  /* Check that the output buffer is large enough for the temporary file 
+  ** name. If it is not, return SQLITE_ERROR.
+  */
+  if( (strlen(zDir) + strlen(SQLITE_TEMP_FILE_PREFIX) + 17) >= (size_t)nBuf ){
+    return SQLITE_ERROR;
+  }
 
-/*
-** Acquire a lock on the handle h
-*/
-static void winceMutexAcquire(HANDLE h){
-   DWORD dwErr;
-   do {
-     dwErr = WaitForSingleObject(h, INFINITE);
-   } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
+  do{
+    sqlite3_snprintf(nBuf-17, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir);
+    j = (int)strlen(zBuf);
+    sqlite3_randomness(15, &zBuf[j]);
+    for(i=0; i<15; i++, j++){
+      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+    }
+    zBuf[j] = 0;
+  }while( access(zBuf,0)==0 );
+  return SQLITE_OK;
 }
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
 /*
-** Release a lock acquired by winceMutexAcquire()
+** Routine to transform a unixFile into a proxy-locking unixFile.
+** Implementation in the proxy-lock division, but used by unixOpen()
+** if SQLITE_PREFER_PROXY_LOCKING is defined.
 */
-#define winceMutexRelease(h) ReleaseMutex(h)
+static int proxyTransformUnixFile(unixFile*, const char*);
+#endif
 
 /*
-** Create the mutex and shared memory used for locking in the file
-** descriptor pFile
+** Search for an unused file descriptor that was opened on the database 
+** file (not a journal or master-journal file) identified by pathname
+** zPath with SQLITE_OPEN_XXX flags matching those passed as the second
+** argument to this function.
+**
+** Such a file descriptor may exist if a database connection was closed
+** but the associated file descriptor could not be closed because some
+** other file descriptor open on the same file is holding a file-lock.
+** Refer to comments in the unixClose() function and the lengthy comment
+** describing "Posix Advisory Locking" at the start of this file for 
+** further details. Also, ticket #4018.
+**
+** If a suitable file descriptor is found, then it is returned. If no
+** such file descriptor is located, -1 is returned.
 */
-static BOOL winceCreateLock(const char *zFilename, winFile *pFile){
-  WCHAR *zTok;
-  WCHAR *zName = utf8ToUnicode(zFilename);
-  BOOL bInit = TRUE;
+static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
+  UnixUnusedFd *pUnused = 0;
 
-  /* Initialize the local lockdata */
-  ZeroMemory(&pFile->local, sizeof(pFile->local));
+  /* Do not search for an unused file descriptor on vxworks. Not because
+  ** vxworks would not benefit from the change (it might, we're not sure),
+  ** but because no way to test it is currently available. It is better 
+  ** not to risk breaking vxworks support for the sake of such an obscure 
+  ** feature.  */
+#if !OS_VXWORKS
+  struct stat sStat;                   /* Results of stat() call */
 
-  /* Replace the backslashes from the filename and lowercase it
-  ** to derive a mutex name. */
-  zTok = CharLowerW(zName);
-  for (;*zTok;zTok++){
-    if (*zTok == '\\') *zTok = '_';
-  }
+  /* A stat() call may fail for various reasons. If this happens, it is
+  ** almost certain that an open() call on the same path will also fail.
+  ** For this reason, if an error occurs in the stat() call here, it is
+  ** ignored and -1 is returned. The caller will try to open a new file
+  ** descriptor on the same path, fail, and return an error to SQLite.
+  **
+  ** Even if a subsequent open() call does succeed, the consequences of
+  ** not searching for a resusable file descriptor are not dire.  */
+  if( 0==stat(zPath, &sStat) ){
+    struct unixOpenCnt *pO;
+    struct unixFileId id;
+    id.dev = sStat.st_dev;
+    id.ino = sStat.st_ino;
 
-  /* Create/open the named mutex */
-  pFile->hMutex = CreateMutexW(NULL, FALSE, zName);
-  if (!pFile->hMutex){
-    free(zName);
-    return FALSE;
+    unixEnterMutex();
+    for(pO=openList; pO && memcmp(&id, &pO->fileId, sizeof(id)); pO=pO->pNext);
+    if( pO ){
+      UnixUnusedFd **pp;
+      for(pp=&pO->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
+      pUnused = *pp;
+      if( pUnused ){
+        *pp = pUnused->pNext;
+      }
+    }
+    unixLeaveMutex();
   }
+#endif    /* if !OS_VXWORKS */
+  return pUnused;
+}
 
-  /* Acquire the mutex before continuing */
-  winceMutexAcquire(pFile->hMutex);
-  
-  /* Since the names of named mutexes, semaphores, file mappings etc are 
-  ** case-sensitive, take advantage of that by uppercasing the mutex name
-  ** and using that as the shared filemapping name.
-  */
-  CharUpperW(zName);
-  pFile->hShared = CreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
-                                       PAGE_READWRITE, 0, sizeof(winceLock),
-                                       zName);  
+/*
+** Open the file zPath.
+** 
+** Previously, the SQLite OS layer used three functions in place of this
+** one:
+**
+**     sqlite3OsOpenReadWrite();
+**     sqlite3OsOpenReadOnly();
+**     sqlite3OsOpenExclusive();
+**
+** These calls correspond to the following combinations of flags:
+**
+**     ReadWrite() ->     (READWRITE | CREATE)
+**     ReadOnly()  ->     (READONLY) 
+**     OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE)
+**
+** The old OpenExclusive() accepted a boolean argument - "delFlag". If
+** true, the file was configured to be automatically deleted when the
+** file handle closed. To achieve the same effect using this new 
+** interface, add the DELETEONCLOSE flag to those specified above for 
+** OpenExclusive().
+*/
+static int unixOpen(
+  sqlite3_vfs *pVfs,           /* The VFS for which this is the xOpen method */
+  const char *zPath,           /* Pathname of file to be opened */
+  sqlite3_file *pFile,         /* The file descriptor to be filled in */
+  int flags,                   /* Input flags to control the opening */
+  int *pOutFlags               /* Output flags returned to SQLite core */
+){
+  unixFile *p = (unixFile *)pFile;
+  int fd = -1;                   /* File descriptor returned by open() */
+  int dirfd = -1;                /* Directory file descriptor */
+  int openFlags = 0;             /* Flags to pass to open() */
+  int eType = flags&0xFFFFFF00;  /* Type of file to open */
+  int noLock;                    /* True to omit locking primitives */
+  int rc = SQLITE_OK;            /* Function Return Code */
 
-  /* Set a flag that indicates we're the first to create the memory so it 
-  ** must be zero-initialized */
-  if (GetLastError() == ERROR_ALREADY_EXISTS){
-    bInit = FALSE;
-  }
+  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
+  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
+  int isCreate     = (flags & SQLITE_OPEN_CREATE);
+  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
+  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
 
-  free(zName);
+  /* If creating a master or main-file journal, this function will open
+  ** a file-descriptor on the directory too. The first time unixSync()
+  ** is called the directory file descriptor will be fsync()ed and close()d.
+  */
+  int isOpenDirectory = (isCreate && 
+      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
+  );
 
-  /* If we succeeded in making the shared memory handle, map it. */
-  if (pFile->hShared){
-    pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, 
-             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
-    /* If mapping failed, close the shared memory handle and erase it */
-    if (!pFile->shared){
-      CloseHandle(pFile->hShared);
-      pFile->hShared = NULL;
-    }
-  }
+  /* If argument zPath is a NULL pointer, this function is required to open
+  ** a temporary file. Use this buffer to store the file name in.
+  */
+  char zTmpname[MAX_PATHNAME+1];
+  const char *zName = zPath;
 
-  /* If shared memory could not be created, then close the mutex and fail */
-  if (pFile->hShared == NULL){
-    winceMutexRelease(pFile->hMutex);
-    CloseHandle(pFile->hMutex);
-    pFile->hMutex = NULL;
-    return FALSE;
-  }
-  
-  /* Initialize the shared memory if we're supposed to */
-  if (bInit) {
-    ZeroMemory(pFile->shared, sizeof(winceLock));
-  }
+  /* Check the following statements are true: 
+  **
+  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
+  **   (b) if CREATE is set, then READWRITE must also be set, and
+  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
+  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
+  */
+  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+  assert(isCreate==0 || isReadWrite);
+  assert(isExclusive==0 || isCreate);
+  assert(isDelete==0 || isCreate);
 
-  winceMutexRelease(pFile->hMutex);
-  return TRUE;
-}
+  /* The main DB, main journal, and master journal are never automatically
+  ** deleted. Nor are they ever temporary files.  */
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
 
-/*
-** Destroy the part of winFile that deals with wince locks
-*/
-static void winceDestroyLock(winFile *pFile){
-  if (pFile->hMutex){
-    /* Acquire the mutex */
-    winceMutexAcquire(pFile->hMutex);
+  /* Assert that the upper layer has set one of the "file-type" flags. */
+  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
+       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
+       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
+       || eType==SQLITE_OPEN_TRANSIENT_DB
+  );
 
-    /* The following blocks should probably assert in debug mode, but they
-       are to cleanup in case any locks remained open */
-    if (pFile->local.nReaders){
-      pFile->shared->nReaders --;
-    }
-    if (pFile->local.bReserved){
-      pFile->shared->bReserved = FALSE;
-    }
-    if (pFile->local.bPending){
-      pFile->shared->bPending = FALSE;
+  memset(p, 0, sizeof(unixFile));
+
+  if( eType==SQLITE_OPEN_MAIN_DB ){
+    UnixUnusedFd *pUnused;
+    pUnused = findReusableFd(zName, flags);
+    if( pUnused ){
+      fd = pUnused->fd;
+    }else{
+      pUnused = sqlite3_malloc(sizeof(*pUnused));
+      if( !pUnused ){
+        return SQLITE_NOMEM;
+      }
     }
-    if (pFile->local.bExclusive){
-      pFile->shared->bExclusive = FALSE;
+    p->pUnused = pUnused;
+  }else if( !zName ){
+    /* If zName is NULL, the upper layer is requesting a temp file. */
+    assert(isDelete && !isOpenDirectory);
+    rc = getTempname(MAX_PATHNAME+1, zTmpname);
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
+    zName = zTmpname;
+  }
 
-    /* De-reference and close our copy of the shared memory handle */
-    UnmapViewOfFile(pFile->shared);
-    CloseHandle(pFile->hShared);
+  /* Determine the value of the flags parameter passed to POSIX function
+  ** open(). These must be calculated even if open() is not called, as
+  ** they may be stored as part of the file handle and used by the 
+  ** 'conch file' locking functions later on.  */
+  if( isReadonly )  openFlags |= O_RDONLY;
+  if( isReadWrite ) openFlags |= O_RDWR;
+  if( isCreate )    openFlags |= O_CREAT;
+  if( isExclusive ) openFlags |= (O_EXCL|O_NOFOLLOW);
+  openFlags |= (O_LARGEFILE|O_BINARY);
 
-    /* Done with the mutex */
-    winceMutexRelease(pFile->hMutex);    
-    CloseHandle(pFile->hMutex);
-    pFile->hMutex = NULL;
+  if( fd<0 ){
+    mode_t openMode = (isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
+    fd = open(zName, openFlags, openMode);
+    OSTRACE4("OPENX   %-3d %s 0%o\n", fd, zName, openFlags);
+    if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
+      /* Failed to open the file for read/write access. Try read-only. */
+      flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+      openFlags &= ~(O_RDWR|O_CREAT);
+      flags |= SQLITE_OPEN_READONLY;
+      openFlags |= O_RDONLY;
+      fd = open(zName, openFlags, openMode);
+    }
+    if( fd<0 ){
+      rc = SQLITE_CANTOPEN;
+      goto open_finished;
+    }
+  }
+  assert( fd>=0 );
+  if( pOutFlags ){
+    *pOutFlags = flags;
   }
-}
 
-/* 
-** An implementation of the LockFile() API of windows for wince
-*/
-static BOOL winceLockFile(
-  HANDLE *phFile,
-  DWORD dwFileOffsetLow,
-  DWORD dwFileOffsetHigh,
-  DWORD nNumberOfBytesToLockLow,
-  DWORD nNumberOfBytesToLockHigh
-){
-  winFile *pFile = HANDLE_TO_WINFILE(phFile);
-  BOOL bReturn = FALSE;
+  if( p->pUnused ){
+    p->pUnused->fd = fd;
+    p->pUnused->flags = flags;
+  }
 
-  if (!pFile->hMutex) return TRUE;
-  winceMutexAcquire(pFile->hMutex);
+  if( isDelete ){
+#if OS_VXWORKS
+    zPath = zName;
+#else
+    unlink(zName);
+#endif
+  }
+#if SQLITE_ENABLE_LOCKING_STYLE
+  else{
+    p->openFlags = openFlags;
+  }
+#endif
 
-  /* Wanting an exclusive lock? */
-  if (dwFileOffsetLow == SHARED_FIRST
-       && nNumberOfBytesToLockLow == SHARED_SIZE){
-    if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
-       pFile->shared->bExclusive = TRUE;
-       pFile->local.bExclusive = TRUE;
-       bReturn = TRUE;
+  if( isOpenDirectory ){
+    rc = openDirectory(zPath, &dirfd);
+    if( rc!=SQLITE_OK ){
+      /* It is safe to close fd at this point, because it is guaranteed not
+      ** to be open on a database file. If it were open on a database file,
+      ** it would not be safe to close as this would release any locks held
+      ** on the file by this process.  */
+      assert( eType!=SQLITE_OPEN_MAIN_DB );
+      close(fd);             /* silently leak if fail, already in error */
+      goto open_finished;
     }
   }
 
-  /* Want a read-only lock? */
-  else if ((dwFileOffsetLow >= SHARED_FIRST &&
-            dwFileOffsetLow < SHARED_FIRST + SHARED_SIZE) &&
-            nNumberOfBytesToLockLow == 1){
-    if (pFile->shared->bExclusive == 0){
-      pFile->local.nReaders ++;
-      if (pFile->local.nReaders == 1){
-        pFile->shared->nReaders ++;
+#ifdef FD_CLOEXEC
+  fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
+#endif
+
+  noLock = eType!=SQLITE_OPEN_MAIN_DB;
+
+#if SQLITE_PREFER_PROXY_LOCKING
+  if( zPath!=NULL && !noLock && pVfs->xOpen ){
+    char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
+    int useProxy = 0;
+
+    /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means 
+    ** never use proxy, NULL means use proxy for non-local files only.  */
+    if( envforce!=NULL ){
+      useProxy = atoi(envforce)>0;
+    }else{
+      struct statfs fsInfo;
+      if( statfs(zPath, &fsInfo) == -1 ){
+        /* In theory, the close(fd) call is sub-optimal. If the file opened
+        ** with fd is a database file, and there are other connections open
+        ** on that file that are currently holding advisory locks on it,
+        ** then the call to close() will cancel those locks. In practice,
+        ** we're assuming that statfs() doesn't fail very often. At least
+        ** not while other file descriptors opened by the same process on
+        ** the same file are working.  */
+        p->lastErrno = errno;
+        if( dirfd>=0 ){
+          close(dirfd); /* silently leak if fail, in error */
+        }
+        close(fd); /* silently leak if fail, in error */
+        rc = SQLITE_IOERR_ACCESS;
+        goto open_finished;
       }
-      bReturn = TRUE;
+      useProxy = !(fsInfo.f_flags&MNT_LOCAL);
     }
-  }
-
-  /* Want a pending lock? */
-  else if (dwFileOffsetLow == PENDING_BYTE && nNumberOfBytesToLockLow == 1){
-    /* If no pending lock has been acquired, then acquire it */
-    if (pFile->shared->bPending == 0) {
-      pFile->shared->bPending = TRUE;
-      pFile->local.bPending = TRUE;
-      bReturn = TRUE;
+    if( useProxy ){
+      rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
+      if( rc==SQLITE_OK ){
+        rc = proxyTransformUnixFile((unixFile*)pFile, ":auto:");
+      }
+      goto open_finished;
     }
   }
-  /* Want a reserved lock? */
-  else if (dwFileOffsetLow == RESERVED_BYTE && nNumberOfBytesToLockLow == 1){
-    if (pFile->shared->bReserved == 0) {
-      pFile->shared->bReserved = TRUE;
-      pFile->local.bReserved = TRUE;
-      bReturn = TRUE;
-    }
+#endif
+  
+  rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
+open_finished:
+  if( rc!=SQLITE_OK ){
+    sqlite3_free(p->pUnused);
   }
-
-  winceMutexRelease(pFile->hMutex);
-  return bReturn;
+  return rc;
 }
 
+
 /*
-** An implementation of the UnlockFile API of windows for wince
+** Delete the file at zPath. If the dirSync argument is true, fsync()
+** the directory after deleting the file.
 */
-static BOOL winceUnlockFile(
-  HANDLE *phFile,
-  DWORD dwFileOffsetLow,
-  DWORD dwFileOffsetHigh,
-  DWORD nNumberOfBytesToUnlockLow,
-  DWORD nNumberOfBytesToUnlockHigh
+static int unixDelete(
+  sqlite3_vfs *NotUsed,     /* VFS containing this as the xDelete method */
+  const char *zPath,        /* Name of file to be deleted */
+  int dirSync               /* If true, fsync() directory after deleting file */
 ){
-  winFile *pFile = HANDLE_TO_WINFILE(phFile);
-  BOOL bReturn = FALSE;
-
-  if (!pFile->hMutex) return TRUE;
-  winceMutexAcquire(pFile->hMutex);
-
-  /* Releasing a reader lock or an exclusive lock */
-  if (dwFileOffsetLow >= SHARED_FIRST &&
-       dwFileOffsetLow < SHARED_FIRST + SHARED_SIZE){
-    /* Did we have an exclusive lock? */
-    if (pFile->local.bExclusive){
-      pFile->local.bExclusive = FALSE;
-      pFile->shared->bExclusive = FALSE;
-      bReturn = TRUE;
-    }
-
-    /* Did we just have a reader lock? */
-    else if (pFile->local.nReaders){
-      pFile->local.nReaders --;
-      if (pFile->local.nReaders == 0)
+  int rc = SQLITE_OK;
+  UNUSED_PARAMETER(NotUsed);
+  SimulateIOError(return SQLITE_IOERR_DELETE);
+  unlink(zPath);
+#ifndef SQLITE_DISABLE_DIRSYNC
+  if( dirSync ){
+    int fd;
+    rc = openDirectory(zPath, &fd);
+    if( rc==SQLITE_OK ){
+#if OS_VXWORKS
+      if( fsync(fd)==-1 )
+#else
+      if( fsync(fd) )
+#endif
       {
-        pFile->shared->nReaders --;
+        rc = SQLITE_IOERR_DIR_FSYNC;
+      }
+      if( close(fd)&&!rc ){
+        rc = SQLITE_IOERR_DIR_CLOSE;
       }
-      bReturn = TRUE;
-    }
-  }
-
-  /* Releasing a pending lock */
-  else if (dwFileOffsetLow == PENDING_BYTE && nNumberOfBytesToUnlockLow == 1){
-    if (pFile->local.bPending){
-      pFile->local.bPending = FALSE;
-      pFile->shared->bPending = FALSE;
-      bReturn = TRUE;
-    }
-  }
-  /* Releasing a reserved lock */
-  else if (dwFileOffsetLow == RESERVED_BYTE && nNumberOfBytesToUnlockLow == 1){
-    if (pFile->local.bReserved) {
-      pFile->local.bReserved = FALSE;
-      pFile->shared->bReserved = FALSE;
-      bReturn = TRUE;
     }
   }
-
-  winceMutexRelease(pFile->hMutex);
-  return bReturn;
+#endif
+  return rc;
 }
 
 /*
-** An implementation of the LockFileEx() API of windows for wince
+** Test the existance of or access permissions of file zPath. The
+** test performed depends on the value of flags:
+**
+**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
+**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
+**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
+**
+** Otherwise return 0.
 */
-static BOOL winceLockFileEx(
-  HANDLE *phFile,
-  DWORD dwFlags,
-  DWORD dwReserved,
-  DWORD nNumberOfBytesToLockLow,
-  DWORD nNumberOfBytesToLockHigh,
-  LPOVERLAPPED lpOverlapped
+static int unixAccess(
+  sqlite3_vfs *NotUsed,   /* The VFS containing this xAccess method */
+  const char *zPath,      /* Path of the file to examine */
+  int flags,              /* What do we want to learn about the zPath file? */
+  int *pResOut            /* Write result boolean here */
 ){
-  /* If the caller wants a shared read lock, forward this call
-  ** to winceLockFile */
-  if (lpOverlapped->Offset == SHARED_FIRST &&
-      dwFlags == 1 &&
-      nNumberOfBytesToLockLow == SHARED_SIZE){
-    return winceLockFile(phFile, SHARED_FIRST, 0, 1, 0);
+  int amode = 0;
+  UNUSED_PARAMETER(NotUsed);
+  SimulateIOError( return SQLITE_IOERR_ACCESS; );
+  switch( flags ){
+    case SQLITE_ACCESS_EXISTS:
+      amode = F_OK;
+      break;
+    case SQLITE_ACCESS_READWRITE:
+      amode = W_OK|R_OK;
+      break;
+    case SQLITE_ACCESS_READ:
+      amode = R_OK;
+      break;
+
+    default:
+      assert(!"Invalid flags argument");
   }
-  return FALSE;
+  *pResOut = (access(zPath, amode)==0);
+  return SQLITE_OK;
 }
-/*
-** End of the special code for wince
-*****************************************************************************/
-#endif /* OS_WINCE */
 
-/*****************************************************************************
-** The next group of routines implement the I/O methods specified
-** by the sqlite3_io_methods object.
-******************************************************************************/
 
 /*
-** Close a file.
+** Turn a relative pathname into a full pathname. The relative path
+** is stored as a nul-terminated string in the buffer pointed to by
+** zPath. 
 **
-** It is reported that an attempt to close a handle might sometimes
-** fail.  This is a very unreasonable result, but windows is notorious
-** for being unreasonable so I do not doubt that it might happen.  If
-** the close fails, we pause for 100 milliseconds and try again.  As
-** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
-** giving up and returning an error.
+** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
+** (in this case, MAX_PATHNAME bytes). The full-path is written to
+** this buffer before returning.
 */
-#define MX_CLOSE_ATTEMPT 3
-static int winClose(sqlite3_file *id){
-  int rc, cnt = 0;
-  winFile *pFile = (winFile*)id;
-  OSTRACE2("CLOSE %d\n", pFile->h);
-  do{
-    rc = CloseHandle(pFile->h);
-  }while( rc==0 && cnt++ < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
-#if OS_WINCE
-#define WINCE_DELETION_ATTEMPTS 3
-  winceDestroyLock(pFile);
-  if( pFile->zDeleteOnClose ){
-    int cnt = 0;
-    while(
-           DeleteFileW(pFile->zDeleteOnClose)==0
-        && GetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff 
-        && cnt++ < WINCE_DELETION_ATTEMPTS
-    ){
-       Sleep(100);  /* Wait a little before trying again */
+static int unixFullPathname(
+  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
+  const char *zPath,            /* Possibly relative input path */
+  int nOut,                     /* Size of output buffer in bytes */
+  char *zOut                    /* Output buffer */
+){
+
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. This function could fail if, for example, the
+  ** current working directory has been unlinked.
+  */
+  SimulateIOError( return SQLITE_ERROR );
+
+  assert( pVfs->mxPathname==MAX_PATHNAME );
+  UNUSED_PARAMETER(pVfs);
+
+  zOut[nOut-1] = '\0';
+  if( zPath[0]=='/' ){
+    sqlite3_snprintf(nOut, zOut, "%s", zPath);
+  }else{
+    int nCwd;
+    if( getcwd(zOut, nOut-1)==0 ){
+      return SQLITE_CANTOPEN;
     }
-    free(pFile->zDeleteOnClose);
+    nCwd = (int)strlen(zOut);
+    sqlite3_snprintf(nOut-nCwd, &zOut[nCwd], "/%s", zPath);
   }
-#endif
-  OpenCounter(-1);
-  return rc ? SQLITE_OK : SQLITE_IOERR;
+  return SQLITE_OK;
 }
 
-/*
-** Some microsoft compilers lack this definition.
-*/
-#ifndef INVALID_SET_FILE_POINTER
-# define INVALID_SET_FILE_POINTER ((DWORD)-1)
-#endif
 
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
 /*
-** Read data from a file into a buffer.  Return SQLITE_OK if all
-** bytes were read successfully and SQLITE_IOERR if anything goes
-** wrong.
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
 */
-static int winRead(
-  sqlite3_file *id,          /* File to read from */
-  void *pBuf,                /* Write content into this buffer */
-  int amt,                   /* Number of bytes to read */
-  sqlite3_int64 offset       /* Begin reading at this offset */
-){
-  LONG upperBits = (offset>>32) & 0x7fffffff;
-  LONG lowerBits = offset & 0xffffffff;
-  DWORD rc;
-  DWORD got;
-  winFile *pFile = (winFile*)id;
-  assert( id!=0 );
-  SimulateIOError(return SQLITE_IOERR_READ);
-  OSTRACE3("READ %d lock=%d\n", pFile->h, pFile->locktype);
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){
-    return SQLITE_FULL;
-  }
-  if( !ReadFile(pFile->h, pBuf, amt, &got, 0) ){
-    return SQLITE_IOERR_READ;
-  }
-  if( got==(DWORD)amt ){
-    return SQLITE_OK;
-  }else{
-    memset(&((char*)pBuf)[got], 0, amt-got);
-    return SQLITE_IOERR_SHORT_READ;
-  }
+#include <dlfcn.h>
+static void *unixDlOpen(sqlite3_vfs *NotUsed, const char *zFilename){
+  UNUSED_PARAMETER(NotUsed);
+  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
 }
 
 /*
-** Write data from a buffer into a file.  Return SQLITE_OK on success
-** or some other error code on failure.
+** SQLite calls this function immediately after a call to unixDlSym() or
+** unixDlOpen() fails (returns a null pointer). If a more detailed error
+** message is available, it is written to zBufOut. If no error message
+** is available, zBufOut is left unmodified and SQLite uses a default
+** error message.
 */
-static int winWrite(
-  sqlite3_file *id,         /* File to write into */
-  const void *pBuf,         /* The bytes to be written */
-  int amt,                  /* Number of bytes to write */
-  sqlite3_int64 offset      /* Offset into the file to begin writing at */
-){
-  LONG upperBits = (offset>>32) & 0x7fffffff;
-  LONG lowerBits = offset & 0xffffffff;
-  DWORD rc;
-  DWORD wrote;
-  winFile *pFile = (winFile*)id;
-  assert( id!=0 );
-  SimulateIOError(return SQLITE_IOERR_WRITE);
-  SimulateDiskfullError(return SQLITE_FULL);
-  OSTRACE3("WRITE %d lock=%d\n", pFile->h, pFile->locktype);
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){
-    return SQLITE_FULL;
-  }
-  assert( amt>0 );
-  while(
-     amt>0
-     && (rc = WriteFile(pFile->h, pBuf, amt, &wrote, 0))!=0
-     && wrote>0
-  ){
-    amt -= wrote;
-    pBuf = &((char*)pBuf)[wrote];
-  }
-  if( !rc || amt>(int)wrote ){
-    return SQLITE_FULL;
+static void unixDlError(sqlite3_vfs *NotUsed, int nBuf, char *zBufOut){
+  char *zErr;
+  UNUSED_PARAMETER(NotUsed);
+  unixEnterMutex();
+  zErr = dlerror();
+  if( zErr ){
+    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
   }
-  return SQLITE_OK;
+  unixLeaveMutex();
 }
-
-/*
-** Truncate an open file to a specified size
-*/
-static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
-  LONG upperBits = (nByte>>32) & 0x7fffffff;
-  LONG lowerBits = nByte & 0xffffffff;
-  winFile *pFile = (winFile*)id;
-  OSTRACE3("TRUNCATE %d %lld\n", pFile->h, nByte);
-  SimulateIOError(return SQLITE_IOERR_TRUNCATE);
-  SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  SetEndOfFile(pFile->h);
-  return SQLITE_OK;
+static void (*unixDlSym(sqlite3_vfs *NotUsed, void *p, const char*zSym))(void){
+  /* 
+  ** GCC with -pedantic-errors says that C90 does not allow a void* to be
+  ** cast into a pointer to a function.  And yet the library dlsym() routine
+  ** returns a void* which is really a pointer to a function.  So how do we
+  ** use dlsym() with -pedantic-errors?
+  **
+  ** Variable x below is defined to be a pointer to a function taking
+  ** parameters void* and const char* and returning a pointer to a function.
+  ** We initialize x by assigning it a pointer to the dlsym() function.
+  ** (That assignment requires a cast.)  Then we call the function that
+  ** x points to.  
+  **
+  ** This work-around is unlikely to work correctly on any system where
+  ** you really cannot cast a function pointer into void*.  But then, on the
+  ** other hand, dlsym() will not work on such a system either, so we have
+  ** not really lost anything.
+  */
+  void (*(*x)(void*,const char*))(void);
+  UNUSED_PARAMETER(NotUsed);
+  x = (void(*(*)(void*,const char*))(void))dlsym;
+  return (*x)(p, zSym);
+}
+static void unixDlClose(sqlite3_vfs *NotUsed, void *pHandle){
+  UNUSED_PARAMETER(NotUsed);
+  dlclose(pHandle);
 }
-
-#ifdef SQLITE_TEST
-/*
-** Count the number of fullsyncs and normal syncs.  This is used to test
-** that syncs and fullsyncs are occuring at the right times.
-*/
-SQLITE_API int sqlite3_sync_count = 0;
-SQLITE_API int sqlite3_fullsync_count = 0;
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+  #define unixDlOpen  0
+  #define unixDlError 0
+  #define unixDlSym   0
+  #define unixDlClose 0
 #endif
 
 /*
-** Make sure all writes to a particular file are committed to disk.
+** Write nBuf bytes of random data to the supplied buffer zBuf.
 */
-static int winSync(sqlite3_file *id, int flags){
-  winFile *pFile = (winFile*)id;
-  OSTRACE3("SYNC %d lock=%d\n", pFile->h, pFile->locktype);
-#ifdef SQLITE_TEST
-  if( flags & SQLITE_SYNC_FULL ){
-    sqlite3_fullsync_count++;
+static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
+  UNUSED_PARAMETER(NotUsed);
+  assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));
+
+  /* We have to initialize zBuf to prevent valgrind from reporting
+  ** errors.  The reports issued by valgrind are incorrect - we would
+  ** prefer that the randomness be increased by making use of the
+  ** uninitialized space in zBuf - but valgrind errors tend to worry
+  ** some users.  Rather than argue, it seems easier just to initialize
+  ** the whole array and silence valgrind, even if that means less randomness
+  ** in the random seed.
+  **
+  ** When testing, initializing zBuf[] to zero is all we do.  That means
+  ** that we always use the same random number sequence.  This makes the
+  ** tests repeatable.
+  */
+  memset(zBuf, 0, nBuf);
+#if !defined(SQLITE_TEST)
+  {
+    int pid, fd;
+    fd = open("/dev/urandom", O_RDONLY);
+    if( fd<0 ){
+      time_t t;
+      time(&t);
+      memcpy(zBuf, &t, sizeof(t));
+      pid = getpid();
+      memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid));
+      assert( sizeof(t)+sizeof(pid)<=(size_t)nBuf );
+      nBuf = sizeof(t) + sizeof(pid);
+    }else{
+      nBuf = read(fd, zBuf, nBuf);
+      close(fd);
+    }
   }
-  sqlite3_sync_count++;
 #endif
-  if( FlushFileBuffers(pFile->h) ){
-    return SQLITE_OK;
-  }else{
-    return SQLITE_IOERR;
-  }
+  return nBuf;
 }
 
+
 /*
-** Determine the current size of a file in bytes
+** Sleep for a little while.  Return the amount of time slept.
+** The argument is the number of microseconds we want to sleep.
+** The return value is the number of microseconds of sleep actually
+** requested from the underlying operating system, a number which
+** might be greater than or equal to the argument, but not less
+** than the argument.
 */
-static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
-  winFile *pFile = (winFile*)id;
-  DWORD upperBits, lowerBits;
-  SimulateIOError(return SQLITE_IOERR_FSTAT);
-  lowerBits = GetFileSize(pFile->h, &upperBits);
-  *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
-  return SQLITE_OK;
+static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
+#if OS_VXWORKS
+  struct timespec sp;
+
+  sp.tv_sec = microseconds / 1000000;
+  sp.tv_nsec = (microseconds % 1000000) * 1000;
+  nanosleep(&sp, NULL);
+  UNUSED_PARAMETER(NotUsed);
+  return microseconds;
+#elif defined(HAVE_USLEEP) && HAVE_USLEEP
+  usleep(microseconds);
+  UNUSED_PARAMETER(NotUsed);
+  return microseconds;
+#else
+  int seconds = (microseconds+999999)/1000000;
+  sleep(seconds);
+  UNUSED_PARAMETER(NotUsed);
+  return seconds*1000000;
+#endif
 }
 
 /*
-** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
+** The following variable, if set to a non-zero value, is interpreted as
+** the number of seconds since 1970 and is used to set the result of
+** sqlite3OsCurrentTime() during testing.
 */
-#ifndef LOCKFILE_FAIL_IMMEDIATELY
-# define LOCKFILE_FAIL_IMMEDIATELY 1
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
 #endif
 
 /*
-** Acquire a reader lock.
-** Different API routines are called depending on whether or not this
-** is Win95 or WinNT.
+** Find the current time (in Universal Coordinated Time).  Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0.  Return 1 if the time and date cannot be found.
 */
-static int getReadLock(winFile *pFile){
-  int res;
-  if( isNT() ){
-    OVERLAPPED ovlp;
-    ovlp.Offset = SHARED_FIRST;
-    ovlp.OffsetHigh = 0;
-    ovlp.hEvent = 0;
-    res = LockFileEx(pFile->h, LOCKFILE_FAIL_IMMEDIATELY,
-                     0, SHARED_SIZE, 0, &ovlp);
-  }else{
-    int lk;
-    sqlite3_randomness(sizeof(lk), &lk);
-    pFile->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
-    res = LockFile(pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
+#if defined(SQLITE_OMIT_FLOATING_POINT)
+  time_t t;
+  time(&t);
+  *prNow = (((sqlite3_int64)t)/8640 + 24405875)/10;
+#elif defined(NO_GETTOD)
+  time_t t;
+  time(&t);
+  *prNow = t/86400.0 + 2440587.5;
+#elif OS_VXWORKS
+  struct timespec sNow;
+  clock_gettime(CLOCK_REALTIME, &sNow);
+  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_nsec/86400000000000.0;
+#else
+  struct timeval sNow;
+  gettimeofday(&sNow, 0);
+  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_usec/86400000000.0;
+#endif
+
+#ifdef SQLITE_TEST
+  if( sqlite3_current_time ){
+    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
   }
-  return res;
+#endif
+  UNUSED_PARAMETER(NotUsed);
+  return 0;
 }
 
 /*
-** Undo a readlock
+** We added the xGetLastError() method with the intention of providing
+** better low-level error messages when operating-system problems come up
+** during SQLite operation.  But so far, none of that has been implemented
+** in the core.  So this routine is never called.  For now, it is merely
+** a place-holder.
 */
-static int unlockReadLock(winFile *pFile){
-  int res;
-  if( isNT() ){
-    res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
-  }else{
-    res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0);
-  }
-  return res;
+static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
+  UNUSED_PARAMETER(NotUsed);
+  UNUSED_PARAMETER(NotUsed2);
+  UNUSED_PARAMETER(NotUsed3);
+  return 0;
 }
 
 /*
-** Lock the file with the lock specified by parameter locktype - one
-** of the following:
+************************ End of sqlite3_vfs methods ***************************
+******************************************************************************/
+
+/******************************************************************************
+************************** Begin Proxy Locking ********************************
+**
+** Proxy locking is a "uber-locking-method" in this sense:  It uses the
+** other locking methods on secondary lock files.  Proxy locking is a
+** meta-layer over top of the primitive locking implemented above.  For
+** this reason, the division that implements of proxy locking is deferred
+** until late in the file (here) after all of the other I/O methods have
+** been defined - so that the primitive locking methods are available
+** as services to help with the implementation of proxy locking.
+**
+****
+**
+** The default locking schemes in SQLite use byte-range locks on the
+** database file to coordinate safe, concurrent access by multiple readers
+** and writers [http://sqlite.org/lockingv3.html].  The five file locking
+** states (UNLOCKED, PENDING, SHARED, RESERVED, EXCLUSIVE) are implemented
+** as POSIX read & write locks over fixed set of locations (via fsctl),
+** on AFP and SMB only exclusive byte-range locks are available via fsctl
+** with _IOWR('z', 23, struct ByteRangeLockPB2) to track the same 5 states.
+** To simulate a F_RDLCK on the shared range, on AFP a randomly selected
+** address in the shared range is taken for a SHARED lock, the entire
+** shared range is taken for an EXCLUSIVE lock):
+**
+**      PENDING_BYTE        0x40000000		   	
+**      RESERVED_BYTE       0x40000001
+**      SHARED_RANGE        0x40000002 -> 0x40000200
+**
+** This works well on the local file system, but shows a nearly 100x
+** slowdown in read performance on AFP because the AFP client disables
+** the read cache when byte-range locks are present.  Enabling the read
+** cache exposes a cache coherency problem that is present on all OS X
+** supported network file systems.  NFS and AFP both observe the
+** close-to-open semantics for ensuring cache coherency
+** [http://nfs.sourceforge.net/#faq_a8], which does not effectively
+** address the requirements for concurrent database access by multiple
+** readers and writers
+** [http://www.nabble.com/SQLite-on-NFS-cache-coherency-td15655701.html].
+**
+** To address the performance and cache coherency issues, proxy file locking
+** changes the way database access is controlled by limiting access to a
+** single host at a time and moving file locks off of the database file
+** and onto a proxy file on the local file system.  
 **
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
 **
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
+** Using proxy locks
+** -----------------
+**
+** C APIs
+**
+**  sqlite3_file_control(db, dbname, SQLITE_SET_LOCKPROXYFILE,
+**                       <proxy_path> | ":auto:");
+**  sqlite3_file_control(db, dbname, SQLITE_GET_LOCKPROXYFILE, &<proxy_path>);
+**
+**
+** SQL pragmas
+**
+**  PRAGMA [database.]lock_proxy_file=<proxy_path> | :auto:
+**  PRAGMA [database.]lock_proxy_file
 **
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
+** Specifying ":auto:" means that if there is a conch file with a matching
+** host ID in it, the proxy path in the conch file will be used, otherwise
+** a proxy path based on the user's temp dir
+** (via confstr(_CS_DARWIN_USER_TEMP_DIR,...)) will be used and the
+** actual proxy file name is generated from the name and path of the
+** database file.  For example:
 **
-** This routine will only increase a lock.  The winUnlock() routine
-** erases all locks at once and returns us immediately to locking level 0.
-** It is not possible to lower the locking level one step at a time.  You
-** must go straight to locking level 0.
+**       For database path "/Users/me/foo.db" 
+**       The lock path will be "<tmpdir>/sqliteplocks/_Users_me_foo.db:auto:")
+**
+** Once a lock proxy is configured for a database connection, it can not
+** be removed, however it may be switched to a different proxy path via
+** the above APIs (assuming the conch file is not being held by another
+** connection or process). 
+**
+**
+** How proxy locking works
+** -----------------------
+**
+** Proxy file locking relies primarily on two new supporting files: 
+**
+**   *  conch file to limit access to the database file to a single host
+**      at a time
+**
+**   *  proxy file to act as a proxy for the advisory locks normally
+**      taken on the database
+**
+** The conch file - to use a proxy file, sqlite must first "hold the conch"
+** by taking an sqlite-style shared lock on the conch file, reading the
+** contents and comparing the host's unique host ID (see below) and lock
+** proxy path against the values stored in the conch.  The conch file is
+** stored in the same directory as the database file and the file name
+** is patterned after the database file name as ".<databasename>-conch".
+** If the conch file does not exist, or it's contents do not match the
+** host ID and/or proxy path, then the lock is escalated to an exclusive
+** lock and the conch file contents is updated with the host ID and proxy
+** path and the lock is downgraded to a shared lock again.  If the conch
+** is held by another process (with a shared lock), the exclusive lock
+** will fail and SQLITE_BUSY is returned.
+**
+** The proxy file - a single-byte file used for all advisory file locks
+** normally taken on the database file.   This allows for safe sharing
+** of the database file for multiple readers and writers on the same
+** host (the conch ensures that they all use the same local lock file).
+**
+** There is a third file - the host ID file - used as a persistent record
+** of a unique identifier for the host, a 128-byte unique host id file
+** in the path defined by the HOSTIDPATH macro (default value is
+** /Library/Caches/.com.apple.sqliteConchHostId).
+**
+** Requesting the lock proxy does not immediately take the conch, it is
+** only taken when the first request to lock database file is made.  
+** This matches the semantics of the traditional locking behavior, where
+** opening a connection to a database file does not take a lock on it.
+** The shared lock and an open file descriptor are maintained until 
+** the connection to the database is closed. 
+**
+** The proxy file and the lock file are never deleted so they only need
+** to be created the first time they are used.
+**
+** Configuration options
+** ---------------------
+**
+**  SQLITE_PREFER_PROXY_LOCKING
+**
+**       Database files accessed on non-local file systems are
+**       automatically configured for proxy locking, lock files are
+**       named automatically using the same logic as
+**       PRAGMA lock_proxy_file=":auto:"
+**    
+**  SQLITE_PROXY_DEBUG
+**
+**       Enables the logging of error messages during host id file
+**       retrieval and creation
+**
+**  HOSTIDPATH
+**
+**       Overrides the default host ID file path location
+**
+**  LOCKPROXYDIR
+**
+**       Overrides the default directory used for lock proxy files that
+**       are named automatically via the ":auto:" setting
+**
+**  SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+**
+**       Permissions to use when creating a directory for storing the
+**       lock proxy files, only used when LOCKPROXYDIR is not set.
+**    
+**    
+** As mentioned above, when compiled with SQLITE_PREFER_PROXY_LOCKING,
+** setting the environment variable SQLITE_FORCE_PROXY_LOCKING to 1 will
+** force proxy locking to be used for every database file opened, and 0
+** will force automatic proxy locking to be disabled for all database
+** files (explicity calling the SQLITE_SET_LOCKPROXYFILE pragma or
+** sqlite_file_control API is not affected by SQLITE_FORCE_PROXY_LOCKING).
 */
-static int winLock(sqlite3_file *id, int locktype){
-  int rc = SQLITE_OK;    /* Return code from subroutines */
-  int res = 1;           /* Result of a windows lock call */
-  int newLocktype;       /* Set pFile->locktype to this value before exiting */
-  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
-  winFile *pFile = (winFile*)id;
 
-  assert( pFile!=0 );
-  OSTRACE5("LOCK %d %d was %d(%d)\n",
-          pFile->h, locktype, pFile->locktype, pFile->sharedLockByte);
+/*
+** Proxy locking is only available on MacOSX 
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
 
-  /* If there is already a lock of this type or more restrictive on the
-  ** OsFile, do nothing. Don't use the end_lock: exit path, as
-  ** sqlite3OsEnterMutex() hasn't been called yet.
-  */
-  if( pFile->locktype>=locktype ){
-    return SQLITE_OK;
-  }
+#ifdef SQLITE_TEST
+/* simulate multiple hosts by creating unique hostid file paths */
+SQLITE_API int sqlite3_hostid_num = 0;
+#endif
 
-  /* Make sure the locking sequence is correct
-  */
-  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
-  assert( locktype!=PENDING_LOCK );
-  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
+/*
+** The proxyLockingContext has the path and file structures for the remote 
+** and local proxy files in it
+*/
+typedef struct proxyLockingContext proxyLockingContext;
+struct proxyLockingContext {
+  unixFile *conchFile;         /* Open conch file */
+  char *conchFilePath;         /* Name of the conch file */
+  unixFile *lockProxy;         /* Open proxy lock file */
+  char *lockProxyPath;         /* Name of the proxy lock file */
+  char *dbPath;                /* Name of the open file */
+  int conchHeld;               /* True if the conch is currently held */
+  void *oldLockingContext;     /* Original lockingcontext to restore on close */
+  sqlite3_io_methods const *pOldMethod;     /* Original I/O methods for close */
+};
 
-  /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
-  ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
-  ** the PENDING_LOCK byte is temporary.
-  */
-  newLocktype = pFile->locktype;
-  if( pFile->locktype==NO_LOCK
-   || (locktype==EXCLUSIVE_LOCK && pFile->locktype==RESERVED_LOCK)
-  ){
-    int cnt = 3;
-    while( cnt-->0 && (res = LockFile(pFile->h, PENDING_BYTE, 0, 1, 0))==0 ){
-      /* Try 3 times to get the pending lock.  The pending lock might be
-      ** held by another reader process who will release it momentarily.
-      */
-      OSTRACE2("could not get a PENDING lock. cnt=%d\n", cnt);
-      Sleep(1);
+/* HOSTIDLEN and CONCHLEN both include space for the string 
+** terminating nul 
+*/
+#define HOSTIDLEN         128
+#define CONCHLEN          (MAXPATHLEN+HOSTIDLEN+1)
+#ifndef HOSTIDPATH
+# define HOSTIDPATH       "/Library/Caches/.com.apple.sqliteConchHostId"
+#endif
+
+/* basically a copy of unixRandomness with different
+** test behavior built in */
+static int proxyGenerateHostID(char *pHostID){
+  int pid, fd, len;
+  unsigned char *key = (unsigned char *)pHostID;
+  
+  memset(key, 0, HOSTIDLEN);
+  len = 0;
+  fd = open("/dev/urandom", O_RDONLY);
+  if( fd>=0 ){
+    len = read(fd, key, HOSTIDLEN);
+    close(fd); /* silently leak the fd if it fails */
+  }
+  if( len < HOSTIDLEN ){
+    time_t t;
+    time(&t);
+    memcpy(key, &t, sizeof(t));
+    pid = getpid();
+    memcpy(&key[sizeof(t)], &pid, sizeof(pid));
+  }
+  
+#ifdef MAKE_PRETTY_HOSTID
+  {
+    int i;
+    /* filter the bytes into printable ascii characters and NUL terminate */
+    key[(HOSTIDLEN-1)] = 0x00;
+    for( i=0; i<(HOSTIDLEN-1); i++ ){
+      unsigned char pa = key[i]&0x7F;
+      if( pa<0x20 ){
+        key[i] = (key[i]&0x80 == 0x80) ? pa+0x40 : pa+0x20;
+      }else if( pa==0x7F ){
+        key[i] = (key[i]&0x80 == 0x80) ? pa=0x20 : pa+0x7E;
+      }
     }
-    gotPendingLock = res;
   }
+#endif
+  return SQLITE_OK;
+}
 
-  /* Acquire a shared lock
-  */
-  if( locktype==SHARED_LOCK && res ){
-    assert( pFile->locktype==NO_LOCK );
-    res = getReadLock(pFile);
-    if( res ){
-      newLocktype = SHARED_LOCK;
-    }
+/* writes the host id path to path, path should be an pre-allocated buffer
+** with enough space for a path 
+*/
+static void proxyGetHostIDPath(char *path, size_t len){
+  strlcpy(path, HOSTIDPATH, len);
+#ifdef SQLITE_TEST
+  if( sqlite3_hostid_num>0 ){
+    char suffix[2] = "1";
+    suffix[0] = suffix[0] + sqlite3_hostid_num;
+    strlcat(path, suffix, len);
   }
+#endif
+  OSTRACE3("GETHOSTIDPATH  %s pid=%d\n", path, getpid());
+}
 
-  /* Acquire a RESERVED lock
-  */
-  if( locktype==RESERVED_LOCK && res ){
-    assert( pFile->locktype==SHARED_LOCK );
-    res = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
-    if( res ){
-      newLocktype = RESERVED_LOCK;
+/* get the host ID from a sqlite hostid file stored in the 
+** user-specific tmp directory, create the ID if it's not there already 
+*/
+static int proxyGetHostID(char *pHostID, int *pError){
+  int fd;
+  char path[MAXPATHLEN]; 
+  size_t len;
+  int rc=SQLITE_OK;
+
+  proxyGetHostIDPath(path, MAXPATHLEN);
+  /* try to create the host ID file, if it already exists read the contents */
+  fd = open(path, O_CREAT|O_WRONLY|O_EXCL, 0644);
+  if( fd<0 ){
+    int err=errno;
+		
+    if( err!=EEXIST ){
+#ifdef SQLITE_PROXY_DEBUG /* set the sqlite error message instead */
+      fprintf(stderr, "sqlite error creating host ID file %s: %s\n",
+              path, strerror(err));
+#endif
+      return SQLITE_PERM;
     }
+    /* couldn't create the file, read it instead */
+    fd = open(path, O_RDONLY|O_EXCL);
+    if( fd<0 ){
+#ifdef SQLITE_PROXY_DEBUG /* set the sqlite error message instead */
+      int err = errno;
+      fprintf(stderr, "sqlite error opening host ID file %s: %s\n",
+              path, strerror(err));
+#endif
+      return SQLITE_PERM;
+    }
+    len = pread(fd, pHostID, HOSTIDLEN, 0);
+    if( len<0 ){
+      *pError = errno;
+      rc = SQLITE_IOERR_READ;
+    }else if( len<HOSTIDLEN ){
+      *pError = 0;
+      rc = SQLITE_IOERR_SHORT_READ;
+    }
+    close(fd); /* silently leak the fd if it fails */
+    OSTRACE3("GETHOSTID  read %s pid=%d\n", pHostID, getpid());
+    return rc;
+  }else{
+    /* we're creating the host ID file (use a random string of bytes) */
+    proxyGenerateHostID(pHostID);
+    len = pwrite(fd, pHostID, HOSTIDLEN, 0);
+    if( len<0 ){
+      *pError = errno;
+      rc = SQLITE_IOERR_WRITE;
+    }else if( len<HOSTIDLEN ){
+      *pError = 0;
+      rc = SQLITE_IOERR_WRITE;
+    }
+    close(fd); /* silently leak the fd if it fails */
+    OSTRACE3("GETHOSTID  wrote %s pid=%d\n", pHostID, getpid());
+    return rc;
   }
+}
 
-  /* Acquire a PENDING lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res ){
-    newLocktype = PENDING_LOCK;
-    gotPendingLock = 0;
-  }
+static int proxyGetLockPath(const char *dbPath, char *lPath, size_t maxLen){
+  int len;
+  int dbLen;
+  int i;
 
-  /* Acquire an EXCLUSIVE lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res ){
-    assert( pFile->locktype>=SHARED_LOCK );
-    res = unlockReadLock(pFile);
-    OSTRACE2("unreadlock = %d\n", res);
-    res = LockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
-    if( res ){
-      newLocktype = EXCLUSIVE_LOCK;
+#ifdef LOCKPROXYDIR
+  len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
+#else
+# ifdef _CS_DARWIN_USER_TEMP_DIR
+  {
+    confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen);
+    len = strlcat(lPath, "sqliteplocks", maxLen);
+    if( mkdir(lPath, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
+      /* if mkdir fails, handle as lock file creation failure */
+#  ifdef SQLITE_DEBUG
+      int err = errno;
+      if( err!=EEXIST ){
+        fprintf(stderr, "proxyGetLockPath: mkdir(%s,0%o) error %d %s\n", lPath,
+                SQLITE_DEFAULT_PROXYDIR_PERMISSIONS, err, strerror(err));
+      }
+#  endif
     }else{
-      OSTRACE2("error-code = %d\n", GetLastError());
-      getReadLock(pFile);
+      OSTRACE3("GETLOCKPATH  mkdir %s pid=%d\n", lPath, getpid());
     }
+    
+  }
+# else
+  len = strlcpy(lPath, "/tmp/", maxLen);
+# endif
+#endif
+
+  if( lPath[len-1]!='/' ){
+    len = strlcat(lPath, "/", maxLen);
   }
+  
+  /* transform the db path to a unique cache name */
+  dbLen = (int)strlen(dbPath);
+  for( i=0; i<dbLen && (i+len+7)<maxLen; i++){
+    char c = dbPath[i];
+    lPath[i+len] = (c=='/')?'_':c;
+  }
+  lPath[i+len]='\0';
+  strlcat(lPath, ":auto:", maxLen);
+  return SQLITE_OK;
+}
 
-  /* If we are holding a PENDING lock that ought to be released, then
-  ** release it now.
-  */
-  if( gotPendingLock && locktype==SHARED_LOCK ){
-    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
+/*
+** Create a new VFS file descriptor (stored in memory obtained from
+** sqlite3_malloc) and open the file named "path" in the file descriptor.
+**
+** The caller is responsible not only for closing the file descriptor
+** but also for freeing the memory associated with the file descriptor.
+*/
+static int proxyCreateUnixFile(const char *path, unixFile **ppFile) {
+  unixFile *pNew;
+  int flags = SQLITE_OPEN_MAIN_DB|SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE;
+  int rc = SQLITE_OK;
+  sqlite3_vfs dummyVfs;
+
+  pNew = (unixFile *)sqlite3_malloc(sizeof(unixFile));
+  if( !pNew ){
+    return SQLITE_NOMEM;
   }
+  memset(pNew, 0, sizeof(unixFile));
 
-  /* Update the state of the lock has held in the file descriptor then
-  ** return the appropriate result code.
+  /* Call unixOpen() to open the proxy file. The flags passed to unixOpen()
+  ** suggest that the file being opened is a "main database". This is
+  ** necessary as other file types do not necessarily support locking. It
+  ** is better to use unixOpen() instead of opening the file directly with
+  ** open(), as unixOpen() sets up the various mechanisms required to
+  ** make sure a call to close() does not cause the system to discard
+  ** POSIX locks prematurely.
+  **
+  ** It is important that the xOpen member of the VFS object passed to 
+  ** unixOpen() is NULL. This tells unixOpen() may try to open a proxy-file 
+  ** for the proxy-file (creating a potential infinite loop).
   */
-  if( res ){
-    rc = SQLITE_OK;
-  }else{
-    OSTRACE4("LOCK FAILED %d trying for %d but got %d\n", pFile->h,
-           locktype, newLocktype);
-    rc = SQLITE_BUSY;
+  dummyVfs.pAppData = (void*)&autolockIoFinder;
+  dummyVfs.xOpen = 0;
+  rc = unixOpen(&dummyVfs, path, (sqlite3_file *)pNew, flags, &flags);
+  if( rc==SQLITE_OK && (flags&SQLITE_OPEN_READONLY) ){
+    pNew->pMethod->xClose((sqlite3_file *)pNew);
+    rc = SQLITE_CANTOPEN;
   }
-  pFile->locktype = newLocktype;
+
+  if( rc!=SQLITE_OK ){
+    sqlite3_free(pNew);
+    pNew = 0;
+  }
+
+  *ppFile = pNew;
   return rc;
 }
 
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, return
-** non-zero, otherwise zero.
+/* takes the conch by taking a shared lock and read the contents conch, if 
+** lockPath is non-NULL, the host ID and lock file path must match.  A NULL 
+** lockPath means that the lockPath in the conch file will be used if the 
+** host IDs match, or a new lock path will be generated automatically 
+** and written to the conch file.
 */
-static int winCheckReservedLock(sqlite3_file *id){
-  int rc;
-  winFile *pFile = (winFile*)id;
-  assert( pFile!=0 );
-  if( pFile->locktype>=RESERVED_LOCK ){
-    rc = 1;
-    OSTRACE3("TEST WR-LOCK %d %d (local)\n", pFile->h, rc);
+static int proxyTakeConch(unixFile *pFile){
+  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext; 
+  
+  if( pCtx->conchHeld>0 ){
+    return SQLITE_OK;
   }else{
-    rc = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
-    if( rc ){
-      UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
+    unixFile *conchFile = pCtx->conchFile;
+    char testValue[CONCHLEN];
+    char conchValue[CONCHLEN];
+    char lockPath[MAXPATHLEN];
+    char *tLockPath = NULL;
+    int rc = SQLITE_OK;
+    int readRc = SQLITE_OK;
+    int syncPerms = 0;
+
+    OSTRACE4("TAKECONCH  %d for %s pid=%d\n", conchFile->h,
+             (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), getpid());
+
+    rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, SHARED_LOCK);
+    if( rc==SQLITE_OK ){
+      int pError = 0;
+      memset(testValue, 0, CONCHLEN); /* conch is fixed size */
+      rc = proxyGetHostID(testValue, &pError);
+      if( (rc&0xff)==SQLITE_IOERR ){
+        pFile->lastErrno = pError;
+      }
+      if( pCtx->lockProxyPath ){
+        strlcpy(&testValue[HOSTIDLEN], pCtx->lockProxyPath, MAXPATHLEN);
+      }
     }
-    rc = !rc;
-    OSTRACE3("TEST WR-LOCK %d %d (remote)\n", pFile->h, rc);
+    if( rc!=SQLITE_OK ){
+      goto end_takeconch;
+    }
+    
+    readRc = unixRead((sqlite3_file *)conchFile, conchValue, CONCHLEN, 0);
+    if( readRc!=SQLITE_IOERR_SHORT_READ ){
+      if( readRc!=SQLITE_OK ){
+        if( (rc&0xff)==SQLITE_IOERR ){
+          pFile->lastErrno = conchFile->lastErrno;
+        }
+        rc = readRc;
+        goto end_takeconch;
+      }
+      /* if the conch has data compare the contents */
+      if( !pCtx->lockProxyPath ){
+        /* for auto-named local lock file, just check the host ID and we'll
+         ** use the local lock file path that's already in there */
+        if( !memcmp(testValue, conchValue, HOSTIDLEN) ){
+          tLockPath = (char *)&conchValue[HOSTIDLEN];
+          goto end_takeconch;
+        }
+      }else{
+        /* we've got the conch if conchValue matches our path and host ID */
+        if( !memcmp(testValue, conchValue, CONCHLEN) ){
+          goto end_takeconch;
+        }
+      }
+    }else{
+      /* a short read means we're "creating" the conch (even though it could 
+      ** have been user-intervention), if we acquire the exclusive lock,
+      ** we'll try to match the current on-disk permissions of the database
+      */
+      syncPerms = 1;
+    }
+    
+    /* either conch was emtpy or didn't match */
+    if( !pCtx->lockProxyPath ){
+      proxyGetLockPath(pCtx->dbPath, lockPath, MAXPATHLEN);
+      tLockPath = lockPath;
+      strlcpy(&testValue[HOSTIDLEN], lockPath, MAXPATHLEN);
+    }
+    
+    /* update conch with host and path (this will fail if other process
+     ** has a shared lock already) */
+    rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, EXCLUSIVE_LOCK);
+    if( rc==SQLITE_OK ){
+      rc = unixWrite((sqlite3_file *)conchFile, testValue, CONCHLEN, 0);
+      if( rc==SQLITE_OK && syncPerms ){
+        struct stat buf;
+        int err = fstat(pFile->h, &buf);
+        if( err==0 ){
+          /* try to match the database file permissions, ignore failure */
+#ifndef SQLITE_PROXY_DEBUG
+          fchmod(conchFile->h, buf.st_mode);
+#else
+          if( fchmod(conchFile->h, buf.st_mode)!=0 ){
+            int code = errno;
+            fprintf(stderr, "fchmod %o FAILED with %d %s\n",
+                             buf.st_mode, code, strerror(code));
+          } else {
+            fprintf(stderr, "fchmod %o SUCCEDED\n",buf.st_mode);
+          }
+        }else{
+          int code = errno;
+          fprintf(stderr, "STAT FAILED[%d] with %d %s\n", 
+                          err, code, strerror(code));
+#endif
+        }
+      }
+    }
+    conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, SHARED_LOCK);
+  
+end_takeconch:
+    OSTRACE2("TRANSPROXY: CLOSE  %d\n", pFile->h);
+    if( rc==SQLITE_OK && pFile->openFlags ){
+      if( pFile->h>=0 ){
+#ifdef STRICT_CLOSE_ERROR
+        if( close(pFile->h) ){
+          pFile->lastErrno = errno;
+          return SQLITE_IOERR_CLOSE;
+        }
+#else
+        close(pFile->h); /* silently leak fd if fail */
+#endif
+      }
+      pFile->h = -1;
+      int fd = open(pCtx->dbPath, pFile->openFlags,
+                    SQLITE_DEFAULT_FILE_PERMISSIONS);
+      OSTRACE2("TRANSPROXY: OPEN  %d\n", fd);
+      if( fd>=0 ){
+        pFile->h = fd;
+      }else{
+        rc=SQLITE_CANTOPEN; /* SQLITE_BUSY? proxyTakeConch called
+                               during locking */
+      }
+    }
+    if( rc==SQLITE_OK && !pCtx->lockProxy ){
+      char *path = tLockPath ? tLockPath : pCtx->lockProxyPath;
+      /* ACS: Need to make a copy of path sometimes */
+      rc = proxyCreateUnixFile(path, &pCtx->lockProxy);
+    }
+    if( rc==SQLITE_OK ){
+      pCtx->conchHeld = 1;
+
+      if( tLockPath ){
+        pCtx->lockProxyPath = sqlite3DbStrDup(0, tLockPath);
+        if( pCtx->lockProxy->pMethod == &afpIoMethods ){
+          ((afpLockingContext *)pCtx->lockProxy->lockingContext)->dbPath =
+                     pCtx->lockProxyPath;
+        }
+      }
+    } else {
+      conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+    }
+    OSTRACE3("TAKECONCH  %d %s\n", conchFile->h, rc==SQLITE_OK?"ok":"failed");
+    return rc;
   }
+}
+
+/*
+** If pFile holds a lock on a conch file, then release that lock.
+*/
+static int proxyReleaseConch(unixFile *pFile){
+  int rc;                     /* Subroutine return code */
+  proxyLockingContext *pCtx;  /* The locking context for the proxy lock */
+  unixFile *conchFile;        /* Name of the conch file */
+
+  pCtx = (proxyLockingContext *)pFile->lockingContext;
+  conchFile = pCtx->conchFile;
+  OSTRACE4("RELEASECONCH  %d for %s pid=%d\n", conchFile->h,
+           (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), 
+           getpid());
+  pCtx->conchHeld = 0;
+  rc = conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+  OSTRACE3("RELEASECONCH  %d %s\n", conchFile->h,
+           (rc==SQLITE_OK ? "ok" : "failed"));
   return rc;
 }
 
 /*
-** Lower the locking level on file descriptor id to locktype.  locktype
-** must be either NO_LOCK or SHARED_LOCK.
+** Given the name of a database file, compute the name of its conch file.
+** Store the conch filename in memory obtained from sqlite3_malloc().
+** Make *pConchPath point to the new name.  Return SQLITE_OK on success
+** or SQLITE_NOMEM if unable to obtain memory.
 **
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
+** The caller is responsible for ensuring that the allocated memory
+** space is eventually freed.
 **
-** It is not possible for this routine to fail if the second argument
-** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
-** might return SQLITE_IOERR;
+** *pConchPath is set to NULL if a memory allocation error occurs.
 */
-static int winUnlock(sqlite3_file *id, int locktype){
-  int type;
-  winFile *pFile = (winFile*)id;
-  int rc = SQLITE_OK;
-  assert( pFile!=0 );
-  assert( locktype<=SHARED_LOCK );
-  OSTRACE5("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype,
-          pFile->locktype, pFile->sharedLockByte);
-  type = pFile->locktype;
-  if( type>=EXCLUSIVE_LOCK ){
-    UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
-    if( locktype==SHARED_LOCK && !getReadLock(pFile) ){
-      /* This should never happen.  We should always be able to
-      ** reacquire the read lock */
-      rc = SQLITE_IOERR_UNLOCK;
-    }
-  }
-  if( type>=RESERVED_LOCK ){
-    UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
+static int proxyCreateConchPathname(char *dbPath, char **pConchPath){
+  int i;                        /* Loop counter */
+  int len = (int)strlen(dbPath); /* Length of database filename - dbPath */
+  char *conchPath;              /* buffer in which to construct conch name */
+
+  /* Allocate space for the conch filename and initialize the name to
+  ** the name of the original database file. */  
+  *pConchPath = conchPath = (char *)sqlite3_malloc(len + 8);
+  if( conchPath==0 ){
+    return SQLITE_NOMEM;
   }
-  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
-    unlockReadLock(pFile);
+  memcpy(conchPath, dbPath, len+1);
+  
+  /* now insert a "." before the last / character */
+  for( i=(len-1); i>=0; i-- ){
+    if( conchPath[i]=='/' ){
+      i++;
+      break;
+    }
   }
-  if( type>=PENDING_LOCK ){
-    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
+  conchPath[i]='.';
+  while ( i<len ){
+    conchPath[i+1]=dbPath[i];
+    i++;
   }
-  pFile->locktype = locktype;
-  return rc;
+
+  /* append the "-conch" suffix to the file */
+  memcpy(&conchPath[i+1], "-conch", 7);
+  assert( (int)strlen(conchPath) == len+7 );
+
+  return SQLITE_OK;
 }
 
-/*
-** Control and query of the open file handle.
+
+/* Takes a fully configured proxy locking-style unix file and switches
+** the local lock file path 
 */
-static int winFileControl(sqlite3_file *id, int op, void *pArg){
-  switch( op ){
-    case SQLITE_FCNTL_LOCKSTATE: {
-      *(int*)pArg = ((winFile*)id)->locktype;
-      return SQLITE_OK;
+static int switchLockProxyPath(unixFile *pFile, const char *path) {
+  proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
+  char *oldPath = pCtx->lockProxyPath;
+  int rc = SQLITE_OK;
+
+  if( pFile->locktype!=NO_LOCK ){
+    return SQLITE_BUSY;
+  }  
+
+  /* nothing to do if the path is NULL, :auto: or matches the existing path */
+  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ||
+    (oldPath && !strncmp(oldPath, path, MAXPATHLEN)) ){
+    return SQLITE_OK;
+  }else{
+    unixFile *lockProxy = pCtx->lockProxy;
+    pCtx->lockProxy=NULL;
+    pCtx->conchHeld = 0;
+    if( lockProxy!=NULL ){
+      rc=lockProxy->pMethod->xClose((sqlite3_file *)lockProxy);
+      if( rc ) return rc;
+      sqlite3_free(lockProxy);
     }
+    sqlite3_free(oldPath);
+    pCtx->lockProxyPath = sqlite3DbStrDup(0, path);
   }
-  return SQLITE_ERROR;
+  
+  return rc;
 }
 
 /*
-** Return the sector size in bytes of the underlying block device for
-** the specified file. This is almost always 512 bytes, but may be
-** larger for some devices.
+** pFile is a file that has been opened by a prior xOpen call.  dbPath
+** is a string buffer at least MAXPATHLEN+1 characters in size.
 **
-** SQLite code assumes this function cannot fail. It also assumes that
-** if two files are created in the same file-system directory (i.e.
-** a database and its journal file) that the sector size will be the
-** same for both.
+** This routine find the filename associated with pFile and writes it
+** int dbPath.
 */
-static int winSectorSize(sqlite3_file *id){
-  return SQLITE_DEFAULT_SECTOR_SIZE;
+static int proxyGetDbPathForUnixFile(unixFile *pFile, char *dbPath){
+#if defined(__APPLE__)
+  if( pFile->pMethod == &afpIoMethods ){
+    /* afp style keeps a reference to the db path in the filePath field 
+    ** of the struct */
+    assert( (int)strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+    strcpy(dbPath, ((afpLockingContext *)pFile->lockingContext)->dbPath);
+  }else
+#endif
+  if( pFile->pMethod == &dotlockIoMethods ){
+    /* dot lock style uses the locking context to store the dot lock
+    ** file path */
+    int len = strlen((char *)pFile->lockingContext) - strlen(DOTLOCK_SUFFIX);
+    memcpy(dbPath, (char *)pFile->lockingContext, len + 1);
+  }else{
+    /* all other styles use the locking context to store the db file path */
+    assert( strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+    strcpy(dbPath, (char *)pFile->lockingContext);
+  }
+  return SQLITE_OK;
 }
 
 /*
-** Return a vector of device characteristics.
+** Takes an already filled in unix file and alters it so all file locking 
+** will be performed on the local proxy lock file.  The following fields
+** are preserved in the locking context so that they can be restored and 
+** the unix structure properly cleaned up at close time:
+**  ->lockingContext
+**  ->pMethod
 */
-static int winDeviceCharacteristics(sqlite3_file *id){
-  return 0;
-}
+static int proxyTransformUnixFile(unixFile *pFile, const char *path) {
+  proxyLockingContext *pCtx;
+  char dbPath[MAXPATHLEN+1];       /* Name of the database file */
+  char *lockPath=NULL;
+  int rc = SQLITE_OK;
+  
+  if( pFile->locktype!=NO_LOCK ){
+    return SQLITE_BUSY;
+  }
+  proxyGetDbPathForUnixFile(pFile, dbPath);
+  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ){
+    lockPath=NULL;
+  }else{
+    lockPath=(char *)path;
+  }
+  
+  OSTRACE4("TRANSPROXY  %d for %s pid=%d\n", pFile->h,
+           (lockPath ? lockPath : ":auto:"), getpid());
 
-/*
-** This vector defines all the methods that can operate on an
-** sqlite3_file for win32.
-*/
-static const sqlite3_io_methods winIoMethod = {
-  1,                        /* iVersion */
-  winClose,
-  winRead,
-  winWrite,
-  winTruncate,
-  winSync,
-  winFileSize,
-  winLock,
-  winUnlock,
-  winCheckReservedLock,
-  winFileControl,
-  winSectorSize,
-  winDeviceCharacteristics
-};
+  pCtx = sqlite3_malloc( sizeof(*pCtx) );
+  if( pCtx==0 ){
+    return SQLITE_NOMEM;
+  }
+  memset(pCtx, 0, sizeof(*pCtx));
 
-/***************************************************************************
-** Here ends the I/O methods that form the sqlite3_io_methods object.
-**
-** The next block of code implements the VFS methods.
-****************************************************************************/
+  rc = proxyCreateConchPathname(dbPath, &pCtx->conchFilePath);
+  if( rc==SQLITE_OK ){
+    rc = proxyCreateUnixFile(pCtx->conchFilePath, &pCtx->conchFile);
+  }  
+  if( rc==SQLITE_OK && lockPath ){
+    pCtx->lockProxyPath = sqlite3DbStrDup(0, lockPath);
+  }
 
-/*
-** Convert a UTF-8 filename into whatever form the underlying
-** operating system wants filenames in.  Space to hold the result
-** is obtained from malloc and must be freed by the calling
-** function.
-*/
-static void *convertUtf8Filename(const char *zFilename){
-  void *zConverted = 0;
-  if( isNT() ){
-    zConverted = utf8ToUnicode(zFilename);
+  if( rc==SQLITE_OK ){
+    /* all memory is allocated, proxys are created and assigned, 
+    ** switch the locking context and pMethod then return.
+    */
+    pCtx->dbPath = sqlite3DbStrDup(0, dbPath);
+    pCtx->oldLockingContext = pFile->lockingContext;
+    pFile->lockingContext = pCtx;
+    pCtx->pOldMethod = pFile->pMethod;
+    pFile->pMethod = &proxyIoMethods;
   }else{
-    zConverted = utf8ToMbcs(zFilename);
+    if( pCtx->conchFile ){ 
+      rc = pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
+      if( rc ) return rc;
+      sqlite3_free(pCtx->conchFile);
+    }
+    sqlite3_free(pCtx->conchFilePath); 
+    sqlite3_free(pCtx);
   }
-  /* caller will handle out of memory */
-  return zConverted;
+  OSTRACE3("TRANSPROXY  %d %s\n", pFile->h,
+           (rc==SQLITE_OK ? "ok" : "failed"));
+  return rc;
 }
 
+
 /*
-** Open a file.
+** This routine handles sqlite3_file_control() calls that are specific
+** to proxy locking.
 */
-static int winOpen(
-  sqlite3_vfs *pVfs,        /* Not used */
-  const char *zName,        /* Name of the file (UTF-8) */
-  sqlite3_file *id,         /* Write the SQLite file handle here */
-  int flags,                /* Open mode flags */
-  int *pOutFlags            /* Status return flags */
-){
-  HANDLE h;
-  DWORD dwDesiredAccess;
-  DWORD dwShareMode;
-  DWORD dwCreationDisposition;
-  DWORD dwFlagsAndAttributes = 0;
-  int isTemp;
-  winFile *pFile = (winFile*)id;
-  void *zConverted = convertUtf8Filename(zName);
-  if( zConverted==0 ){
-    return SQLITE_NOMEM;
-  }
-
-  if( flags & SQLITE_OPEN_READWRITE ){
-    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
-  }else{
-    dwDesiredAccess = GENERIC_READ;
-  }
-  if( flags & SQLITE_OPEN_CREATE ){
-    dwCreationDisposition = OPEN_ALWAYS;
-  }else{
-    dwCreationDisposition = OPEN_EXISTING;
-  }
-  if( flags & SQLITE_OPEN_MAIN_DB ){
-    dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
-  }else{
-    dwShareMode = 0;
-  }
-  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
-#if OS_WINCE
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
-#else
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
-                               | FILE_ATTRIBUTE_HIDDEN
-                               | FILE_FLAG_DELETE_ON_CLOSE;
-#endif
-    isTemp = 1;
-  }else{
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
-    isTemp = 0;
-  }
-  /* Reports from the internet are that performance is always
-  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
-  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
-  if( isNT() ){
-    h = CreateFileW((WCHAR*)zConverted,
-       dwDesiredAccess,
-       dwShareMode,
-       NULL,
-       dwCreationDisposition,
-       dwFlagsAndAttributes,
-       NULL
-    );
-  }else{
-#if OS_WINCE
-    return SQLITE_NOMEM;
-#else
-    h = CreateFileA((char*)zConverted,
-       dwDesiredAccess,
-       dwShareMode,
-       NULL,
-       dwCreationDisposition,
-       dwFlagsAndAttributes,
-       NULL
-    );
-#endif
-  }
-  if( h==INVALID_HANDLE_VALUE ){
-    free(zConverted);
-    if( flags & SQLITE_OPEN_READWRITE ){
-      return winOpen(0, zName, id, 
-             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
-    }else{
-      return SQLITE_CANTOPEN;
+static int proxyFileControl(sqlite3_file *id, int op, void *pArg){
+  switch( op ){
+    case SQLITE_GET_LOCKPROXYFILE: {
+      unixFile *pFile = (unixFile*)id;
+      if( pFile->pMethod == &proxyIoMethods ){
+        proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
+        proxyTakeConch(pFile);
+        if( pCtx->lockProxyPath ){
+          *(const char **)pArg = pCtx->lockProxyPath;
+        }else{
+          *(const char **)pArg = ":auto: (not held)";
+        }
+      } else {
+        *(const char **)pArg = NULL;
+      }
+      return SQLITE_OK;
     }
-  }
-  if( pOutFlags ){
-    if( flags & SQLITE_OPEN_READWRITE ){
-      *pOutFlags = SQLITE_OPEN_READWRITE;
-    }else{
-      *pOutFlags = SQLITE_OPEN_READONLY;
+    case SQLITE_SET_LOCKPROXYFILE: {
+      unixFile *pFile = (unixFile*)id;
+      int rc = SQLITE_OK;
+      int isProxyStyle = (pFile->pMethod == &proxyIoMethods);
+      if( pArg==NULL || (const char *)pArg==0 ){
+        if( isProxyStyle ){
+          /* turn off proxy locking - not supported */
+          rc = SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
+        }else{
+          /* turn off proxy locking - already off - NOOP */
+          rc = SQLITE_OK;
+        }
+      }else{
+        const char *proxyPath = (const char *)pArg;
+        if( isProxyStyle ){
+          proxyLockingContext *pCtx = 
+            (proxyLockingContext*)pFile->lockingContext;
+          if( !strcmp(pArg, ":auto:") 
+           || (pCtx->lockProxyPath &&
+               !strncmp(pCtx->lockProxyPath, proxyPath, MAXPATHLEN))
+          ){
+            rc = SQLITE_OK;
+          }else{
+            rc = switchLockProxyPath(pFile, proxyPath);
+          }
+        }else{
+          /* turn on proxy file locking */
+          rc = proxyTransformUnixFile(pFile, proxyPath);
+        }
+      }
+      return rc;
+    }
+    default: {
+      assert( 0 );  /* The call assures that only valid opcodes are sent */
     }
   }
-  memset(pFile, 0, sizeof(*pFile));
-  pFile->pMethod = &winIoMethod;
-  pFile->h = h;
-#if OS_WINCE
-  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
-               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
-       && !winceCreateLock(zName, pFile)
-  ){
-    CloseHandle(h);
-    free(zConverted);
-    return SQLITE_CANTOPEN;
-  }
-  if( isTemp ){
-    pFile->zDeleteOnClose = zConverted;
-  }else
-#endif
-  {
-    free(zConverted);
-  }
-  OpenCounter(+1);
-  return SQLITE_OK;
+  /*NOTREACHED*/
+  return SQLITE_ERROR;
 }
 
 /*
-** Delete the named file.
-**
-** Note that windows does not allow a file to be deleted if some other
-** process has it open.  Sometimes a virus scanner or indexing program
-** will open a journal file shortly after it is created in order to do
-** whatever does.  While this other process is holding the
-** file open, we will be unable to delete it.  To work around this
-** problem, we delay 100 milliseconds and try to delete again.  Up
-** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
-** up and returning an error.
+** Within this division (the proxying locking implementation) the procedures
+** above this point are all utilities.  The lock-related methods of the
+** proxy-locking sqlite3_io_method object follow.
 */
-#define MX_DELETION_ATTEMPTS 5
-static int winDelete(
-  sqlite3_vfs *pVfs,          /* Not used on win32 */
-  const char *zFilename,      /* Name of file to delete */
-  int syncDir                 /* Not used on win32 */
-){
-  int cnt = 0;
-  int rc;
-  void *zConverted = convertUtf8Filename(zFilename);
-  if( zConverted==0 ){
-    return SQLITE_NOMEM;
-  }
-  SimulateIOError(return SQLITE_IOERR_DELETE);
-  if( isNT() ){
-    do{
-      DeleteFileW(zConverted);
-    }while( (rc = GetFileAttributesW(zConverted))!=0xffffffff 
-            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
-  }else{
-#if OS_WINCE
-    return SQLITE_NOMEM;
-#else
-    do{
-      DeleteFileA(zConverted);
-    }while( (rc = GetFileAttributesA(zConverted))!=0xffffffff
-            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
-#endif
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int proxyCheckReservedLock(sqlite3_file *id, int *pResOut) {
+  unixFile *pFile = (unixFile*)id;
+  int rc = proxyTakeConch(pFile);
+  if( rc==SQLITE_OK ){
+    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+    unixFile *proxy = pCtx->lockProxy;
+    return proxy->pMethod->xCheckReservedLock((sqlite3_file*)proxy, pResOut);
   }
-  free(zConverted);
-  OSTRACE2("DELETE \"%s\"\n", zFilename);
-  return rc==0xffffffff ? SQLITE_OK : SQLITE_IOERR_DELETE;
+  return rc;
 }
 
 /*
-** Check the existance and status of a file.
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock.  Use the sqlite3OsUnlock()
+** routine to lower a locking level.
 */
-static int winAccess(
-  sqlite3_vfs *pVfs,         /* Not used on win32 */
-  const char *zFilename,     /* Name of file to check */
-  int flags                  /* Type of test to make on this file */
-){
-  DWORD attr;
-  int rc;
-  void *zConverted = convertUtf8Filename(zFilename);
-  if( zConverted==0 ){
-    return SQLITE_NOMEM;
-  }
-  if( isNT() ){
-    attr = GetFileAttributesW((WCHAR*)zConverted);
-  }else{
-#if OS_WINCE
-    return SQLITE_NOMEM;
-#else
-    attr = GetFileAttributesA((char*)zConverted);
-#endif
-  }
-  free(zConverted);
-  switch( flags ){
-    case SQLITE_ACCESS_READ:
-    case SQLITE_ACCESS_EXISTS:
-      rc = attr!=0xffffffff;
-      break;
-    case SQLITE_ACCESS_READWRITE:
-      rc = (attr & FILE_ATTRIBUTE_READONLY)==0;
-      break;
-    default:
-      assert(!"Invalid flags argument");
+static int proxyLock(sqlite3_file *id, int locktype) {
+  unixFile *pFile = (unixFile*)id;
+  int rc = proxyTakeConch(pFile);
+  if( rc==SQLITE_OK ){
+    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+    unixFile *proxy = pCtx->lockProxy;
+    rc = proxy->pMethod->xLock((sqlite3_file*)proxy, locktype);
+    pFile->locktype = proxy->locktype;
   }
   return rc;
 }
 
 
 /*
-** Create a temporary file name in zBuf.  zBuf must be big enough to
-** hold at pVfs->mxPathname characters.
+** Lower the locking level on file descriptor pFile to locktype.  locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
 */
-static int winGetTempname(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  static char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  int i, j;
-  char zTempPath[MAX_PATH+1];
-  if( sqlite3_temp_directory ){
-    sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
-  }else if( isNT() ){
-    char *zMulti;
-    WCHAR zWidePath[MAX_PATH];
-    GetTempPathW(MAX_PATH-30, zWidePath);
-    zMulti = unicodeToUtf8(zWidePath);
-    if( zMulti ){
-      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zMulti);
-      free(zMulti);
-    }else{
-      return SQLITE_NOMEM;
-    }
-  }else{
-    char *zUtf8;
-    char zMbcsPath[MAX_PATH];
-    GetTempPathA(MAX_PATH-30, zMbcsPath);
-    zUtf8 = mbcsToUtf8(zMbcsPath);
-    if( zUtf8 ){
-      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zUtf8);
-      free(zUtf8);
-    }else{
-      return SQLITE_NOMEM;
-    }
-  }
-  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
-  zTempPath[i] = 0;
-  sqlite3_snprintf(nBuf-30, zBuf,
-                   "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
-  j = strlen(zBuf);
-  sqlite3_randomness(20, &zBuf[j]);
-  for(i=0; i<20; i++, j++){
-    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+static int proxyUnlock(sqlite3_file *id, int locktype) {
+  unixFile *pFile = (unixFile*)id;
+  int rc = proxyTakeConch(pFile);
+  if( rc==SQLITE_OK ){
+    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+    unixFile *proxy = pCtx->lockProxy;
+    rc = proxy->pMethod->xUnlock((sqlite3_file*)proxy, locktype);
+    pFile->locktype = proxy->locktype;
   }
-  zBuf[j] = 0;
-  OSTRACE2("TEMP FILENAME: %s\n", zBuf);
-  return SQLITE_OK; 
+  return rc;
 }
 
 /*
-** Turn a relative pathname into a full pathname.  Write the full
-** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
-** bytes in size.
+** Close a file that uses proxy locks.
 */
-static int winFullPathname(
-  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
-  const char *zRelative,        /* Possibly relative input path */
-  int nFull,                    /* Size of output buffer in bytes */
-  char *zFull                   /* Output buffer */
-){
-
-#if defined(__CYGWIN__)
-  cygwin_conv_to_full_win32_path(zRelative, zFull);
-  return SQLITE_OK;
-#endif
-
-#if OS_WINCE
-  /* WinCE has no concept of a relative pathname, or so I am told. */
-  sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative);
-  return SQLITE_OK;
-#endif
-
-#if !OS_WINCE && !defined(__CYGWIN__)
-  int nByte;
-  void *zConverted;
-  char *zOut;
-  zConverted = convertUtf8Filename(zRelative);
-  if( isNT() ){
-    WCHAR *zTemp;
-    nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3;
-    zTemp = malloc( nByte*sizeof(zTemp[0]) );
-    if( zTemp==0 ){
-      free(zConverted);
-      return SQLITE_NOMEM;
+static int proxyClose(sqlite3_file *id) {
+  if( id ){
+    unixFile *pFile = (unixFile*)id;
+    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+    unixFile *lockProxy = pCtx->lockProxy;
+    unixFile *conchFile = pCtx->conchFile;
+    int rc = SQLITE_OK;
+    
+    if( lockProxy ){
+      rc = lockProxy->pMethod->xUnlock((sqlite3_file*)lockProxy, NO_LOCK);
+      if( rc ) return rc;
+      rc = lockProxy->pMethod->xClose((sqlite3_file*)lockProxy);
+      if( rc ) return rc;
+      sqlite3_free(lockProxy);
+      pCtx->lockProxy = 0;
     }
-    GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0);
-    free(zConverted);
-    zOut = unicodeToUtf8(zTemp);
-    free(zTemp);
-  }else{
-    char *zTemp;
-    nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
-    zTemp = malloc( nByte*sizeof(zTemp[0]) );
-    if( zTemp==0 ){
-      free(zConverted);
-      return SQLITE_NOMEM;
+    if( conchFile ){
+      if( pCtx->conchHeld ){
+        rc = proxyReleaseConch(pFile);
+        if( rc ) return rc;
+      }
+      rc = conchFile->pMethod->xClose((sqlite3_file*)conchFile);
+      if( rc ) return rc;
+      sqlite3_free(conchFile);
     }
-    GetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
-    free(zConverted);
-    zOut = mbcsToUtf8(zTemp);
-    free(zTemp);
-  }
-  if( zOut ){
-    sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zOut);
-    free(zOut);
-    return SQLITE_OK;
-  }else{
-    return SQLITE_NOMEM;
+    sqlite3_free(pCtx->lockProxyPath);
+    sqlite3_free(pCtx->conchFilePath);
+    sqlite3_free(pCtx->dbPath);
+    /* restore the original locking context and pMethod then close it */
+    pFile->lockingContext = pCtx->oldLockingContext;
+    pFile->pMethod = pCtx->pOldMethod;
+    sqlite3_free(pCtx);
+    return pFile->pMethod->xClose(id);
   }
-#endif
+  return SQLITE_OK;
 }
 
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
+
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
 /*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
-*/
+** The proxy locking style is intended for use with AFP filesystems.
+** And since AFP is only supported on MacOSX, the proxy locking is also
+** restricted to MacOSX.
+** 
+**
+******************* End of the proxy lock implementation **********************
+******************************************************************************/
+
 /*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
+** Initialize the operating system interface.
+**
+** This routine registers all VFS implementations for unix-like operating
+** systems.  This routine, and the sqlite3_os_end() routine that follows,
+** should be the only routines in this file that are visible from other
+** files.
+**
+** This routine is called once during SQLite initialization and by a
+** single thread.  The memory allocation and mutex subsystems have not
+** necessarily been initialized when this routine is called, and so they
+** should not be used.
 */
-static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
-  HANDLE h;
-  void *zConverted = convertUtf8Filename(zFilename);
-  if( zConverted==0 ){
-    return 0;
+SQLITE_API int sqlite3_os_init(void){ 
+  /* 
+  ** The following macro defines an initializer for an sqlite3_vfs object.
+  ** The name of the VFS is NAME.  The pAppData is a pointer to a pointer
+  ** to the "finder" function.  (pAppData is a pointer to a pointer because
+  ** silly C90 rules prohibit a void* from being cast to a function pointer
+  ** and so we have to go through the intermediate pointer to avoid problems
+  ** when compiling with -pedantic-errors on GCC.)
+  **
+  ** The FINDER parameter to this macro is the name of the pointer to the
+  ** finder-function.  The finder-function returns a pointer to the
+  ** sqlite_io_methods object that implements the desired locking
+  ** behaviors.  See the division above that contains the IOMETHODS
+  ** macro for addition information on finder-functions.
+  **
+  ** Most finders simply return a pointer to a fixed sqlite3_io_methods
+  ** object.  But the "autolockIoFinder" available on MacOSX does a little
+  ** more than that; it looks at the filesystem type that hosts the 
+  ** database file and tries to choose an locking method appropriate for
+  ** that filesystem time.
+  */
+  #define UNIXVFS(VFSNAME, FINDER) {                        \
+    1,                    /* iVersion */                    \
+    sizeof(unixFile),     /* szOsFile */                    \
+    MAX_PATHNAME,         /* mxPathname */                  \
+    0,                    /* pNext */                       \
+    VFSNAME,              /* zName */                       \
+    (void*)&FINDER,       /* pAppData */                    \
+    unixOpen,             /* xOpen */                       \
+    unixDelete,           /* xDelete */                     \
+    unixAccess,           /* xAccess */                     \
+    unixFullPathname,     /* xFullPathname */               \
+    unixDlOpen,           /* xDlOpen */                     \
+    unixDlError,          /* xDlError */                    \
+    unixDlSym,            /* xDlSym */                      \
+    unixDlClose,          /* xDlClose */                    \
+    unixRandomness,       /* xRandomness */                 \
+    unixSleep,            /* xSleep */                      \
+    unixCurrentTime,      /* xCurrentTime */                \
+    unixGetLastError      /* xGetLastError */               \
   }
-  if( isNT() ){
-    h = LoadLibraryW((WCHAR*)zConverted);
-  }else{
-#if OS_WINCE
-    return 0;
+
+  /*
+  ** All default VFSes for unix are contained in the following array.
+  **
+  ** Note that the sqlite3_vfs.pNext field of the VFS object is modified
+  ** by the SQLite core when the VFS is registered.  So the following
+  ** array cannot be const.
+  */
+  static sqlite3_vfs aVfs[] = {
+#if SQLITE_ENABLE_LOCKING_STYLE && (OS_VXWORKS || defined(__APPLE__))
+    UNIXVFS("unix",          autolockIoFinder ),
 #else
-    h = LoadLibraryA((char*)zConverted);
+    UNIXVFS("unix",          posixIoFinder ),
 #endif
-  }
-  free(zConverted);
-  return (void*)h;
-}
-static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
-#if OS_WINCE
-  int error = GetLastError();
-  if( error>0x7FFFFFF ){
-    sqlite3_snprintf(nBuf, zBufOut, "OsError 0x%x", error);
-  }else{
-    sqlite3_snprintf(nBuf, zBufOut, "OsError %d", error);
-  }
-#else
-  FormatMessageA(
-    FORMAT_MESSAGE_FROM_SYSTEM,
-    NULL,
-    GetLastError(),
-    0,
-    zBufOut,
-    nBuf-1,
-    0
-  );
+    UNIXVFS("unix-none",     nolockIoFinder ),
+    UNIXVFS("unix-dotfile",  dotlockIoFinder ),
+    UNIXVFS("unix-wfl",      posixWflIoFinder ),
+#if OS_VXWORKS
+    UNIXVFS("unix-namedsem", semIoFinder ),
 #endif
-}
-void *winDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
-#if OS_WINCE
-  /* The GetProcAddressA() routine is only available on wince. */
-  return GetProcAddressA((HANDLE)pHandle, zSymbol);
-#else
-  /* All other windows platforms expect GetProcAddress() to take
-  ** an Ansi string regardless of the _UNICODE setting */
-  return GetProcAddress((HANDLE)pHandle, zSymbol);
+#if SQLITE_ENABLE_LOCKING_STYLE
+    UNIXVFS("unix-posix",    posixIoFinder ),
+#if !OS_VXWORKS
+    UNIXVFS("unix-flock",    flockIoFinder ),
 #endif
-}
-void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
-  FreeLibrary((HANDLE)pHandle);
-}
-#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
-  #define winDlOpen  0
-  #define winDlError 0
-  #define winDlSym   0
-  #define winDlClose 0
 #endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+    UNIXVFS("unix-afp",      afpIoFinder ),
+    UNIXVFS("unix-proxy",    proxyIoFinder ),
+#endif
+  };
+  unsigned int i;          /* Loop counter */
 
+  /* Register all VFSes defined in the aVfs[] array */
+  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
+    sqlite3_vfs_register(&aVfs[i], i==0);
+  }
+  return SQLITE_OK; 
+}
 
 /*
-** Write up to nBuf bytes of randomness into zBuf.
+** Shutdown the operating system interface.
+**
+** Some operating systems might need to do some cleanup in this routine,
+** to release dynamically allocated objects.  But not on unix.
+** This routine is a no-op for unix.
 */
-static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  int n = 0;
-  if( sizeof(SYSTEMTIME)<=nBuf-n ){
-    SYSTEMTIME x;
-    GetSystemTime(&x);
-    memcpy(&zBuf[n], &x, sizeof(x));
-    n += sizeof(x);
-  }
-  if( sizeof(DWORD)<=nBuf-n ){
-    DWORD pid = GetCurrentProcessId();
-    memcpy(&zBuf[n], &pid, sizeof(pid));
-    n += sizeof(pid);
-  }
-  if( sizeof(DWORD)<=nBuf-n ){
-    DWORD cnt = GetTickCount();
-    memcpy(&zBuf[n], &cnt, sizeof(cnt));
-    n += sizeof(cnt);
-  }
-  if( sizeof(LARGE_INTEGER)<=nBuf-n ){
-    LARGE_INTEGER i;
-    QueryPerformanceCounter(&i);
-    memcpy(&zBuf[n], &i, sizeof(i));
-    n += sizeof(i);
-  }
-  return n;
+SQLITE_API int sqlite3_os_end(void){ 
+  return SQLITE_OK; 
 }
+ 
+#endif /* SQLITE_OS_UNIX */
 
-
+/************** End of os_unix.c *********************************************/
+/************** Begin file os_win.c ******************************************/
 /*
-** Sleep for a little while.  Return the amount of time slept.
+** 2004 May 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code that is specific to windows.
 */
-static int winSleep(sqlite3_vfs *pVfs, int microsec){
-  Sleep((microsec+999)/1000);
-  return ((microsec+999)/1000)*1000;
-}
+#if SQLITE_OS_WIN               /* This file is used for windows only */
+
 
 /*
-** The following variable, if set to a non-zero value, becomes the result
-** returned from sqlite3OsCurrentTime().  This is used for testing.
+** A Note About Memory Allocation:
+**
+** This driver uses malloc()/free() directly rather than going through
+** the SQLite-wrappers sqlite3_malloc()/sqlite3_free().  Those wrappers
+** are designed for use on embedded systems where memory is scarce and
+** malloc failures happen frequently.  Win32 does not typically run on
+** embedded systems, and when it does the developers normally have bigger
+** problems to worry about than running out of memory.  So there is not
+** a compelling need to use the wrappers.
+**
+** But there is a good reason to not use the wrappers.  If we use the
+** wrappers then we will get simulated malloc() failures within this
+** driver.  And that causes all kinds of problems for our tests.  We
+** could enhance SQLite to deal with simulated malloc failures within
+** the OS driver, but the code to deal with those failure would not
+** be exercised on Linux (which does not need to malloc() in the driver)
+** and so we would have difficulty writing coverage tests for that
+** code.  Better to leave the code out, we think.
+**
+** The point of this discussion is as follows:  When creating a new
+** OS layer for an embedded system, if you use this file as an example,
+** avoid the use of malloc()/free().  Those routines work ok on windows
+** desktops but not so well in embedded systems.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_current_time = 0;
+
+#include <winbase.h>
+
+#ifdef __CYGWIN__
+# include <sys/cygwin.h>
 #endif
 
 /*
-** Find the current time (in Universal Coordinated Time).  Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0.  Return 1 if the time and date cannot be found.
+** Macros used to determine whether or not to use threads.
 */
-int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
-  FILETIME ft;
-  /* FILETIME structure is a 64-bit value representing the number of 
-     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
-  */
-  double now;
-#if OS_WINCE
-  SYSTEMTIME time;
-  GetSystemTime(&time);
-  SystemTimeToFileTime(&time,&ft);
-#else
-  GetSystemTimeAsFileTime( &ft );
-#endif
-  now = ((double)ft.dwHighDateTime) * 4294967296.0; 
-  *prNow = (now + ft.dwLowDateTime)/864000000000.0 + 2305813.5;
-#ifdef SQLITE_TEST
-  if( sqlite3_current_time ){
-    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
-  }
+#if defined(THREADSAFE) && THREADSAFE
+# define SQLITE_W32_THREADS 1
 #endif
-  return 0;
-}
-
 
 /*
-** Return a pointer to the sqlite3DefaultVfs structure.   We use
-** a function rather than give the structure global scope because
-** some compilers (MSVC) do not allow forward declarations of
-** initialized structures.
+** Include code that is common to all os_*.c files
 */
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
-  static sqlite3_vfs winVfs = {
-    1,                 /* iVersion */
-    sizeof(winFile),   /* szOsFile */
-    MAX_PATH,          /* mxPathname */
-    0,                 /* pNext */
-    "win32",           /* zName */
-    0,                 /* pAppData */
-  
-    winOpen,           /* xOpen */
-    winDelete,         /* xDelete */
-    winAccess,         /* xAccess */
-    winGetTempname,    /* xGetTempName */
-    winFullPathname,   /* xFullPathname */
-    winDlOpen,         /* xDlOpen */
-    winDlError,        /* xDlError */
-    winDlSym,          /* xDlSym */
-    winDlClose,        /* xDlClose */
-    winRandomness,     /* xRandomness */
-    winSleep,          /* xSleep */
-    winCurrentTime     /* xCurrentTime */
-  };
-  
-  return &winVfs;
-}
-
-#endif /* OS_WIN */
-
-/************** End of os_win.c **********************************************/
-/************** Begin file bitvec.c ******************************************/
+/************** Include os_common.h in the middle of os_win.c ****************/
+/************** Begin file os_common.h ***************************************/
 /*
-** 2008 February 16
+** 2004 May 22
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -23389,3267 +27023,2906 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void){
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-*************************************************************************
-** This file implements an object that represents a fixed-length
-** bitmap.  Bits are numbered starting with 1.
-**
-** A bitmap is used to record what pages a database file have been
-** journalled during a transaction.  Usually only a few pages are
-** journalled.  So the bitmap is usually sparse and has low cardinality.
-** But sometimes (for example when during a DROP of a large table) most
-** or all of the pages get journalled.  In those cases, the bitmap becomes
-** dense.  The algorithm needs to handle both cases well.
-**
-** The size of the bitmap is fixed when the object is created.
+******************************************************************************
 **
-** All bits are clear when the bitmap is created.  Individual bits
-** may be set or cleared one at a time.
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
 **
-** Test operations are about 100 times more common that set operations.
-** Clear operations are exceedingly rare.  There are usually between
-** 5 and 500 set operations per Bitvec object, though the number of sets can
-** sometimes grow into tens of thousands or larger.  The size of the
-** Bitvec object is the number of pages in the database file at the
-** start of a transaction, and is thus usually less than a few thousand,
-** but can be as large as 2 billion for a really big database.
+** This file should be #included by the os_*.c files only.  It is not a
+** general purpose header file.
 **
-** @(#) $Id: bitvec.c,v 1.5 2008/05/13 13:27:34 drh Exp $
+** $Id: os_common.h,v 1.38 2009/02/24 18:40:50 danielk1977 Exp $
 */
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
 
-#define BITVEC_SZ        512
-/* Round the union size down to the nearest pointer boundary, since that's how 
-** it will be aligned within the Bitvec struct. */
-#define BITVEC_USIZE     (((BITVEC_SZ-12)/sizeof(Bitvec*))*sizeof(Bitvec*))
-#define BITVEC_NCHAR     BITVEC_USIZE
-#define BITVEC_NBIT      (BITVEC_NCHAR*8)
-#define BITVEC_NINT      (BITVEC_USIZE/4)
-#define BITVEC_MXHASH    (BITVEC_NINT/2)
-#define BITVEC_NPTR      (BITVEC_USIZE/sizeof(Bitvec *))
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch.  The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3OSTrace = 0;
+#define OSTRACE1(X)         if( sqlite3OSTrace ) sqlite3DebugPrintf(X)
+#define OSTRACE2(X,Y)       if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y)
+#define OSTRACE3(X,Y,Z)     if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z)
+#define OSTRACE4(X,Y,Z,A)   if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A)
+#define OSTRACE5(X,Y,Z,A,B) if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A,B)
+#define OSTRACE6(X,Y,Z,A,B,C) \
+    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C)
+#define OSTRACE7(X,Y,Z,A,B,C,D) \
+    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C,D)
+#else
+#define OSTRACE1(X)
+#define OSTRACE2(X,Y)
+#define OSTRACE3(X,Y,Z)
+#define OSTRACE4(X,Y,Z,A)
+#define OSTRACE5(X,Y,Z,A,B)
+#define OSTRACE6(X,Y,Z,A,B,C)
+#define OSTRACE7(X,Y,Z,A,B,C,D)
+#endif
 
-#define BITVEC_HASH(X)   (((X)*37)%BITVEC_NINT)
+/*
+** Macros for performance tracing.  Normally turned off.  Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
 
+/* 
+** hwtime.h contains inline assembler code for implementing 
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
 /*
-** A bitmap is an instance of the following structure.
+** 2008 May 27
 **
-** This bitmap records the existance of zero or more bits
-** with values between 1 and iSize, inclusive.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** There are three possible representations of the bitmap.
-** If iSize<=BITVEC_NBIT, then Bitvec.u.aBitmap[] is a straight
-** bitmap.  The least significant bit is bit 1.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** If iSize>BITVEC_NBIT and iDivisor==0 then Bitvec.u.aHash[] is
-** a hash table that will hold up to BITVEC_MXHASH distinct values.
+******************************************************************************
 **
-** Otherwise, the value i is redirected into one of BITVEC_NPTR
-** sub-bitmaps pointed to by Bitvec.u.apSub[].  Each subbitmap
-** handles up to iDivisor separate values of i.  apSub[0] holds
-** values between 1 and iDivisor.  apSub[1] holds values between
-** iDivisor+1 and 2*iDivisor.  apSub[N] holds values between
-** N*iDivisor+1 and (N+1)*iDivisor.  Each subbitmap is normalized
-** to hold deal with values between 1 and iDivisor.
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+**
+** $Id: hwtime.h,v 1.3 2008/08/01 14:33:15 shane Exp $
 */
-struct Bitvec {
-  u32 iSize;      /* Maximum bit index */
-  u32 nSet;       /* Number of bits that are set */
-  u32 iDivisor;   /* Number of bits handled by each apSub[] entry */
-  union {
-    u8 aBitmap[BITVEC_NCHAR];    /* Bitmap representation */
-    u32 aHash[BITVEC_NINT];      /* Hash table representation */
-    Bitvec *apSub[BITVEC_NPTR];  /* Recursive representation */
-  } u;
-};
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
 
 /*
-** Create a new bitmap object able to handle bits between 0 and iSize,
-** inclusive.  Return a pointer to the new object.  Return NULL if 
-** malloc fails.
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value.  This can be used for high-res
+** profiling.
 */
-SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32 iSize){
-  Bitvec *p;
-  assert( sizeof(*p)==BITVEC_SZ );
-  p = sqlite3MallocZero( sizeof(*p) );
-  if( p ){
-    p->iSize = iSize;
-  }
-  return p;
-}
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+      (defined(i386) || defined(__i386__) || defined(_M_IX86))
 
-/*
-** Check to see if the i-th bit is set.  Return true or false.
-** If p is NULL (if the bitmap has not been created) or if
-** i is out of range, then return false.
-*/
-SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec *p, u32 i){
-  if( p==0 ) return 0;
-  if( i>p->iSize || i==0 ) return 0;
-  if( p->iSize<=BITVEC_NBIT ){
-    i--;
-    return (p->u.aBitmap[i/8] & (1<<(i&7)))!=0;
-  }
-  if( p->iDivisor>0 ){
-    u32 bin = (i-1)/p->iDivisor;
-    i = (i-1)%p->iDivisor + 1;
-    return sqlite3BitvecTest(p->u.apSub[bin], i);
-  }else{
-    u32 h = BITVEC_HASH(i);
-    while( p->u.aHash[h] ){
-      if( p->u.aHash[h]==i ) return 1;
-      h++;
-      if( h>=BITVEC_NINT ) h = 0;
-    }
-    return 0;
-  }
-}
+  #if defined(__GNUC__)
 
-/*
-** Set the i-th bit.  Return 0 on success and an error code if
-** anything goes wrong.
-*/
-SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec *p, u32 i){
-  u32 h;
-  assert( p!=0 );
-  assert( i>0 );
-  assert( i<=p->iSize );
-  if( p->iSize<=BITVEC_NBIT ){
-    i--;
-    p->u.aBitmap[i/8] |= 1 << (i&7);
-    return SQLITE_OK;
-  }
-  if( p->iDivisor ){
-    u32 bin = (i-1)/p->iDivisor;
-    i = (i-1)%p->iDivisor + 1;
-    if( p->u.apSub[bin]==0 ){
-      sqlite3FaultBeginBenign(SQLITE_FAULTINJECTOR_MALLOC);
-      p->u.apSub[bin] = sqlite3BitvecCreate( p->iDivisor );
-      sqlite3FaultEndBenign(SQLITE_FAULTINJECTOR_MALLOC);
-      if( p->u.apSub[bin]==0 ) return SQLITE_NOMEM;
-    }
-    return sqlite3BitvecSet(p->u.apSub[bin], i);
-  }
-  h = BITVEC_HASH(i);
-  while( p->u.aHash[h] ){
-    if( p->u.aHash[h]==i ) return SQLITE_OK;
-    h++;
-    if( h==BITVEC_NINT ) h = 0;
-  }
-  p->nSet++;
-  if( p->nSet>=BITVEC_MXHASH ){
-    int j, rc;
-    u32 aiValues[BITVEC_NINT];
-    memcpy(aiValues, p->u.aHash, sizeof(aiValues));
-    memset(p->u.apSub, 0, sizeof(p->u.apSub[0])*BITVEC_NPTR);
-    p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
-    rc = sqlite3BitvecSet(p, i);
-    for(j=0; j<BITVEC_NINT; j++){
-      if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
-    }
-    return rc;
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+     unsigned int lo, hi;
+     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+     return (sqlite_uint64)hi << 32 | lo;
   }
-  p->u.aHash[h] = i;
-  return SQLITE_OK;
-}
 
-/*
-** Clear the i-th bit.  Return 0 on success and an error code if
-** anything goes wrong.
-*/
-SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec *p, u32 i){
-  assert( p!=0 );
-  assert( i>0 );
-  if( p->iSize<=BITVEC_NBIT ){
-    i--;
-    p->u.aBitmap[i/8] &= ~(1 << (i&7));
-  }else if( p->iDivisor ){
-    u32 bin = (i-1)/p->iDivisor;
-    i = (i-1)%p->iDivisor + 1;
-    if( p->u.apSub[bin] ){
-      sqlite3BitvecClear(p->u.apSub[bin], i);
-    }
-  }else{
-    int j;
-    u32 aiValues[BITVEC_NINT];
-    memcpy(aiValues, p->u.aHash, sizeof(aiValues));
-    memset(p->u.aHash, 0, sizeof(p->u.aHash[0])*BITVEC_NINT);
-    p->nSet = 0;
-    for(j=0; j<BITVEC_NINT; j++){
-      if( aiValues[j] && aiValues[j]!=i ){
-        sqlite3BitvecSet(p, aiValues[j]);
-      }
-    }
-  }
-}
+  #elif defined(_MSC_VER)
 
-/*
-** Destroy a bitmap object.  Reclaim all memory used.
-*/
-SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec *p){
-  if( p==0 ) return;
-  if( p->iDivisor ){
-    int i;
-    for(i=0; i<BITVEC_NPTR; i++){
-      sqlite3BitvecDestroy(p->u.apSub[i]);
-    }
+  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+     __asm {
+        rdtsc
+        ret       ; return value at EDX:EAX
+     }
   }
-  sqlite3_free(p);
-}
 
-#ifndef SQLITE_OMIT_BUILTIN_TEST
-/*
-** Let V[] be an array of unsigned characters sufficient to hold
-** up to N bits.  Let I be an integer between 0 and N.  0<=I<N.
-** Then the following macros can be used to set, clear, or test
-** individual bits within V.
-*/
-#define SETBIT(V,I)      V[I>>3] |= (1<<(I&7))
-#define CLEARBIT(V,I)    V[I>>3] &= ~(1<<(I&7))
-#define TESTBIT(V,I)     (V[I>>3]&(1<<(I&7)))!=0
+  #endif
 
-/*
-** This routine runs an extensive test of the Bitvec code.
-**
-** The input is an array of integers that acts as a program
-** to test the Bitvec.  The integers are opcodes followed
-** by 0, 1, or 3 operands, depending on the opcode.  Another
-** opcode follows immediately after the last operand.
-**
-** There are 6 opcodes numbered from 0 through 5.  0 is the
-** "halt" opcode and causes the test to end.
-**
-**    0          Halt and return the number of errors
-**    1 N S X    Set N bits beginning with S and incrementing by X
-**    2 N S X    Clear N bits beginning with S and incrementing by X
-**    3 N        Set N randomly chosen bits
-**    4 N        Clear N randomly chosen bits
-**    5 N S X    Set N bits from S increment X in array only, not in bitvec
-**
-** The opcodes 1 through 4 perform set and clear operations are performed
-** on both a Bitvec object and on a linear array of bits obtained from malloc.
-** Opcode 5 works on the linear array only, not on the Bitvec.
-** Opcode 5 is used to deliberately induce a fault in order to
-** confirm that error detection works.
-**
-** At the conclusion of the test the linear array is compared
-** against the Bitvec object.  If there are any differences,
-** an error is returned.  If they are the same, zero is returned.
-**
-** If a memory allocation error occurs, return -1.
-*/
-SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int sz, int *aOp){
-  Bitvec *pBitvec = 0;
-  unsigned char *pV = 0;
-  int rc = -1;
-  int i, nx, pc, op;
+#elif (defined(__GNUC__) && defined(__x86_64__))
 
-  /* Allocate the Bitvec to be tested and a linear array of
-  ** bits to act as the reference */
-  pBitvec = sqlite3BitvecCreate( sz );
-  pV = sqlite3_malloc( (sz+7)/8 + 1 );
-  if( pBitvec==0 || pV==0 ) goto bitvec_end;
-  memset(pV, 0, (sz+7)/8 + 1);
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long val;
+      __asm__ __volatile__ ("rdtsc" : "=A" (val));
+      return val;
+  }
+ 
+#elif (defined(__GNUC__) && defined(__ppc__))
 
-  /* Run the program */
-  pc = 0;
-  while( (op = aOp[pc])!=0 ){
-    switch( op ){
-      case 1:
-      case 2:
-      case 5: {
-        nx = 4;
-        i = aOp[pc+2] - 1;
-        aOp[pc+2] += aOp[pc+3];
-        break;
-      }
-      case 3:
-      case 4: 
-      default: {
-        nx = 2;
-        sqlite3_randomness(sizeof(i), &i);
-        break;
-      }
-    }
-    if( (--aOp[pc+1]) > 0 ) nx = 0;
-    pc += nx;
-    i = (i & 0x7fffffff)%sz;
-    if( (op & 1)!=0 ){
-      SETBIT(pV, (i+1));
-      if( op!=5 ){
-        if( sqlite3BitvecSet(pBitvec, i+1) ) goto bitvec_end;
-      }
-    }else{
-      CLEARBIT(pV, (i+1));
-      sqlite3BitvecClear(pBitvec, i+1);
-    }
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long long retval;
+      unsigned long junk;
+      __asm__ __volatile__ ("\n\
+          1:      mftbu   %1\n\
+                  mftb    %L0\n\
+                  mftbu   %0\n\
+                  cmpw    %0,%1\n\
+                  bne     1b"
+                  : "=r" (retval), "=r" (junk));
+      return retval;
   }
 
-  /* Test to make sure the linear array exactly matches the
-  ** Bitvec object.  Start with the assumption that they do
-  ** match (rc==0).  Change rc to non-zero if a discrepancy
-  ** is found.
+#else
+
+  #error Need implementation of sqlite3Hwtime() for your platform.
+
+  /*
+  ** To compile without implementing sqlite3Hwtime() for your platform,
+  ** you can remove the above #error and use the following
+  ** stub function.  You will lose timing support for many
+  ** of the debugging and testing utilities, but it should at
+  ** least compile and run.
   */
-  rc = sqlite3BitvecTest(0,0) + sqlite3BitvecTest(pBitvec, sz+1)
-          + sqlite3BitvecTest(pBitvec, 0);
-  for(i=1; i<=sz; i++){
-    if(  (TESTBIT(pV,i))!=sqlite3BitvecTest(pBitvec,i) ){
-      rc = i;
-      break;
-    }
-  }
+SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
 
-  /* Free allocated structure */
-bitvec_end:
-  sqlite3_free(pV);
-  sqlite3BitvecDestroy(pBitvec);
-  return rc;
-}
-#endif /* SQLITE_OMIT_BUILTIN_TEST */
+#endif
 
-/************** End of bitvec.c **********************************************/
-/************** Begin file pager.c *******************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the implementation of the page cache subsystem or "pager".
-** 
-** The pager is used to access a database disk file.  It implements
-** atomic commit and rollback through the use of a journal file that
-** is separate from the database file.  The pager also implements file
-** locking to prevent two processes from writing the same database
-** file simultaneously, or one process from reading the database while
-** another is writing.
-**
-** @(#) $Id: pager.c,v 1.446 2008/05/13 13:27:34 drh Exp $
-*/
-#ifndef SQLITE_OMIT_DISKIO
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START       g_start=sqlite3Hwtime()
+#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED     g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED     ((sqlite_uint64)0)
+#endif
 
 /*
-** Macros for troubleshooting.  Normally turned off
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error.  This
+** is used for testing the I/O recovery logic.
 */
-#if 0
-#define sqlite3DebugPrintf printf
-#define PAGERTRACE1(X)       sqlite3DebugPrintf(X)
-#define PAGERTRACE2(X,Y)     sqlite3DebugPrintf(X,Y)
-#define PAGERTRACE3(X,Y,Z)   sqlite3DebugPrintf(X,Y,Z)
-#define PAGERTRACE4(X,Y,Z,W) sqlite3DebugPrintf(X,Y,Z,W)
-#define PAGERTRACE5(X,Y,Z,W,V) sqlite3DebugPrintf(X,Y,Z,W,V)
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
+SQLITE_API int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
+SQLITE_API int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
+SQLITE_API int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
+SQLITE_API int sqlite3_io_error_benign = 0;         /* True if errors are benign */
+SQLITE_API int sqlite3_diskfull_pending = 0;
+SQLITE_API int sqlite3_diskfull = 0;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE)  \
+  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+       || sqlite3_io_error_pending-- == 1 )  \
+              { local_ioerr(); CODE; }
+static void local_ioerr(){
+  IOTRACE(("IOERR\n"));
+  sqlite3_io_error_hit++;
+  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+   if( sqlite3_diskfull_pending ){ \
+     if( sqlite3_diskfull_pending == 1 ){ \
+       local_ioerr(); \
+       sqlite3_diskfull = 1; \
+       sqlite3_io_error_hit = 1; \
+       CODE; \
+     }else{ \
+       sqlite3_diskfull_pending--; \
+     } \
+   }
 #else
-#define PAGERTRACE1(X)
-#define PAGERTRACE2(X,Y)
-#define PAGERTRACE3(X,Y,Z)
-#define PAGERTRACE4(X,Y,Z,W)
-#define PAGERTRACE5(X,Y,Z,W,V)
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
 #endif
 
 /*
-** The following two macros are used within the PAGERTRACEX() macros above
-** to print out file-descriptors. 
-**
-** PAGERID() takes a pointer to a Pager struct as its argument. The
-** associated file-descriptor is returned. FILEHANDLEID() takes an sqlite3_file
-** struct as its argument.
+** When testing, keep a count of the number of open files.
 */
-#define PAGERID(p) ((int)(p->fd))
-#define FILEHANDLEID(fd) ((int)fd)
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_open_file_count = 0;
+#define OpenCounter(X)  sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in os_win.c *********************/
 
 /*
-** The page cache as a whole is always in one of the following
-** states:
-**
-**   PAGER_UNLOCK        The page cache is not currently reading or 
-**                       writing the database file.  There is no
-**                       data held in memory.  This is the initial
-**                       state.
-**
-**   PAGER_SHARED        The page cache is reading the database.
-**                       Writing is not permitted.  There can be
-**                       multiple readers accessing the same database
-**                       file at the same time.
-**
-**   PAGER_RESERVED      This process has reserved the database for writing
-**                       but has not yet made any changes.  Only one process
-**                       at a time can reserve the database.  The original
-**                       database file has not been modified so other
-**                       processes may still be reading the on-disk
-**                       database file.
-**
-**   PAGER_EXCLUSIVE     The page cache is writing the database.
-**                       Access is exclusive.  No other processes or
-**                       threads can be reading or writing while one
-**                       process is writing.
-**
-**   PAGER_SYNCED        The pager moves to this state from PAGER_EXCLUSIVE
-**                       after all dirty pages have been written to the
-**                       database file and the file has been synced to
-**                       disk. All that remains to do is to remove or
-**                       truncate the journal file and the transaction 
-**                       will be committed.
-**
-** The page cache comes up in PAGER_UNLOCK.  The first time a
-** sqlite3PagerGet() occurs, the state transitions to PAGER_SHARED.
-** After all pages have been released using sqlite_page_unref(),
-** the state transitions back to PAGER_UNLOCK.  The first time
-** that sqlite3PagerWrite() is called, the state transitions to
-** PAGER_RESERVED.  (Note that sqlite3PagerWrite() can only be
-** called on an outstanding page which means that the pager must
-** be in PAGER_SHARED before it transitions to PAGER_RESERVED.)
-** PAGER_RESERVED means that there is an open rollback journal.
-** The transition to PAGER_EXCLUSIVE occurs before any changes
-** are made to the database file, though writes to the rollback
-** journal occurs with just PAGER_RESERVED.  After an sqlite3PagerRollback()
-** or sqlite3PagerCommitPhaseTwo(), the state can go back to PAGER_SHARED,
-** or it can stay at PAGER_EXCLUSIVE if we are in exclusive access mode.
+** Some microsoft compilers lack this definition.
 */
-#define PAGER_UNLOCK      0
-#define PAGER_SHARED      1   /* same as SHARED_LOCK */
-#define PAGER_RESERVED    2   /* same as RESERVED_LOCK */
-#define PAGER_EXCLUSIVE   4   /* same as EXCLUSIVE_LOCK */
-#define PAGER_SYNCED      5
+#ifndef INVALID_FILE_ATTRIBUTES
+# define INVALID_FILE_ATTRIBUTES ((DWORD)-1) 
+#endif
 
 /*
-** If the SQLITE_BUSY_RESERVED_LOCK macro is set to true at compile-time,
-** then failed attempts to get a reserved lock will invoke the busy callback.
-** This is off by default.  To see why, consider the following scenario:
-** 
-** Suppose thread A already has a shared lock and wants a reserved lock.
-** Thread B already has a reserved lock and wants an exclusive lock.  If
-** both threads are using their busy callbacks, it might be a long time
-** be for one of the threads give up and allows the other to proceed.
-** But if the thread trying to get the reserved lock gives up quickly
-** (if it never invokes its busy callback) then the contention will be
-** resolved quickly.
+** Determine if we are dealing with WindowsCE - which has a much
+** reduced API.
 */
-#ifndef SQLITE_BUSY_RESERVED_LOCK
-# define SQLITE_BUSY_RESERVED_LOCK 0
+#if SQLITE_OS_WINCE
+# define AreFileApisANSI() 1
+# define GetDiskFreeSpaceW() 0
 #endif
 
 /*
-** This macro rounds values up so that if the value is an address it
-** is guaranteed to be an address that is aligned to an 8-byte boundary.
+** WinCE lacks native support for file locking so we have to fake it
+** with some code of our own.
 */
-#define FORCE_ALIGNMENT(X)   (((X)+7)&~7)
-
-typedef struct PgHdr PgHdr;
+#if SQLITE_OS_WINCE
+typedef struct winceLock {
+  int nReaders;       /* Number of reader locks obtained */
+  BOOL bPending;      /* Indicates a pending lock has been obtained */
+  BOOL bReserved;     /* Indicates a reserved lock has been obtained */
+  BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
+} winceLock;
+#endif
 
 /*
-** Each pager stores all currently unreferenced pages in a list sorted
-** in least-recently-used (LRU) order (i.e. the first item on the list has 
-** not been referenced in a long time, the last item has been recently
-** used). An instance of this structure is included as part of each
-** pager structure for this purpose (variable Pager.lru).
-**
-** Additionally, if memory-management is enabled, all unreferenced pages 
-** are stored in a global LRU list (global variable sqlite3LruPageList).
-**
-** In both cases, the PagerLruList.pFirstSynced variable points to
-** the first page in the corresponding list that does not require an
-** fsync() operation before its memory can be reclaimed. If no such
-** page exists, PagerLruList.pFirstSynced is set to NULL.
+** The winFile structure is a subclass of sqlite3_file* specific to the win32
+** portability layer.
 */
-typedef struct PagerLruList PagerLruList;
-struct PagerLruList {
-  PgHdr *pFirst;         /* First page in LRU list */
-  PgHdr *pLast;          /* Last page in LRU list (the most recently used) */
-  PgHdr *pFirstSynced;   /* First page in list with PgHdr.needSync==0 */
+typedef struct winFile winFile;
+struct winFile {
+  const sqlite3_io_methods *pMethod;/* Must be first */
+  HANDLE h;               /* Handle for accessing the file */
+  unsigned char locktype; /* Type of lock currently held on this file */
+  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
+  DWORD lastErrno;        /* The Windows errno from the last I/O error */
+  DWORD sectorSize;       /* Sector size of the device file is on */
+#if SQLITE_OS_WINCE
+  WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
+  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
+  HANDLE hShared;         /* Shared memory segment used for locking */
+  winceLock local;        /* Locks obtained by this instance of winFile */
+  winceLock *shared;      /* Global shared lock memory for the file  */
+#endif
 };
 
 /*
-** The following structure contains the next and previous pointers used
-** to link a PgHdr structure into a PagerLruList linked list. 
+** Forward prototypes.
 */
-typedef struct PagerLruLink PagerLruLink;
-struct PagerLruLink {
-  PgHdr *pNext;
-  PgHdr *pPrev;
-};
+static int getSectorSize(
+    sqlite3_vfs *pVfs,
+    const char *zRelative     /* UTF-8 file name */
+);
 
 /*
-** Each in-memory image of a page begins with the following header.
-** This header is only visible to this pager module.  The client
-** code that calls pager sees only the data that follows the header.
-**
-** Client code should call sqlite3PagerWrite() on a page prior to making
-** any modifications to that page.  The first time sqlite3PagerWrite()
-** is called, the original page contents are written into the rollback
-** journal and PgHdr.inJournal and PgHdr.needSync are set.  Later, once
-** the journal page has made it onto the disk surface, PgHdr.needSync
-** is cleared.  The modified page cannot be written back into the original
-** database file until the journal pages has been synced to disk and the
-** PgHdr.needSync has been cleared.
-**
-** The PgHdr.dirty flag is set when sqlite3PagerWrite() is called and
-** is cleared again when the page content is written back to the original
-** database file.
-**
-** Details of important structure elements:
+** The following variable is (normally) set once and never changes
+** thereafter.  It records whether the operating system is Win95
+** or WinNT.
 **
-** needSync
+** 0:   Operating system unknown.
+** 1:   Operating system is Win95.
+** 2:   Operating system is WinNT.
 **
-**     If this is true, this means that it is not safe to write the page
-**     content to the database because the original content needed
-**     for rollback has not by synced to the main rollback journal.
-**     The original content may have been written to the rollback journal
-**     but it has not yet been synced.  So we cannot write to the database
-**     file because power failure might cause the page in the journal file
-**     to never reach the disk.  It is as if the write to the journal file
-**     does not occur until the journal file is synced.
-**     
-**     This flag is false if the page content exactly matches what
-**     currently exists in the database file.  The needSync flag is also
-**     false if the original content has been written to the main rollback
-**     journal and synced.  If the page represents a new page that has
-**     been added onto the end of the database during the current
-**     transaction, the needSync flag is true until the original database
-**     size in the journal header has been synced to disk.
-**
-** inJournal
-**
-**     This is true if the original page has been written into the main
-**     rollback journal.  This is always false for new pages added to
-**     the end of the database file during the current transaction.
-**     And this flag says nothing about whether or not the journal
-**     has been synced to disk.  For pages that are in the original
-**     database file, the following expression should always be true:
-**
-**       inJournal = sqlite3BitvecTest(pPager->pInJournal, pgno)
-**
-**     The pPager->pInJournal object is only valid for the original
-**     pages of the database, not new pages that are added to the end
-**     of the database, so obviously the above expression cannot be
-**     valid for new pages.  For new pages inJournal is always 0.
-**
-** dirty
-**
-**     When true, this means that the content of the page has been
-**     modified and needs to be written back to the database file.
-**     If false, it means that either the content of the page is
-**     unchanged or else the content is unimportant and we do not
-**     care whether or not it is preserved.
-**
-** alwaysRollback
-**
-**     This means that the sqlite3PagerDontRollback() API should be
-**     ignored for this page.  The DontRollback() API attempts to say
-**     that the content of the page on disk is unimportant (it is an
-**     unused page on the freelist) so that it is unnecessary to 
-**     rollback changes to this page because the content of the page
-**     can change without changing the meaning of the database.  This
-**     flag overrides any DontRollback() attempt.  This flag is set
-**     when a page that originally contained valid data is added to
-**     the freelist.  Later in the same transaction, this page might
-**     be pulled from the freelist and reused for something different
-**     and at that point the DontRollback() API will be called because
-**     pages taken from the freelist do not need to be protected by
-**     the rollback journal.  But this flag says that the page was
-**     not originally part of the freelist so that it still needs to
-**     be rolled back in spite of any subsequent DontRollback() calls.
-**
-** needRead 
-**
-**     This flag means (when true) that the content of the page has
-**     not yet been loaded from disk.  The in-memory content is just
-**     garbage.  (Actually, we zero the content, but you should not
-**     make any assumptions about the content nevertheless.)  If the
-**     content is needed in the future, it should be read from the
-**     original database file.
+** In order to facilitate testing on a WinNT system, the test fixture
+** can manually set this value to 1 to emulate Win98 behavior.
 */
-struct PgHdr {
-  Pager *pPager;                 /* The pager to which this page belongs */
-  Pgno pgno;                     /* The page number for this page */
-  PgHdr *pNextHash, *pPrevHash;  /* Hash collision chain for PgHdr.pgno */
-  PagerLruLink free;             /* Next and previous free pages */
-  PgHdr *pNextAll;               /* A list of all pages */
-  u8 inJournal;                  /* TRUE if has been written to journal */
-  u8 dirty;                      /* TRUE if we need to write back changes */
-  u8 needSync;                   /* Sync journal before writing this page */
-  u8 alwaysRollback;             /* Disable DontRollback() for this page */
-  u8 needRead;                   /* Read content if PagerWrite() is called */
-  short int nRef;                /* Number of users of this page */
-  PgHdr *pDirty, *pPrevDirty;    /* Dirty pages */
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  PagerLruLink gfree;            /* Global list of nRef==0 pages */
-#endif
-#ifdef SQLITE_CHECK_PAGES
-  u32 pageHash;
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_os_type = 0;
+#else
+static int sqlite3_os_type = 0;
 #endif
-  void *pData;                   /* Page data */
-  /* Pager.nExtra bytes of local data appended to this header */
-};
 
 /*
-** For an in-memory only database, some extra information is recorded about
-** each page so that changes can be rolled back.  (Journal files are not
-** used for in-memory databases.)  The following information is added to
-** the end of every EXTRA block for in-memory databases.
+** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
+** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
 **
-** This information could have been added directly to the PgHdr structure.
-** But then it would take up an extra 8 bytes of storage on every PgHdr
-** even for disk-based databases.  Splitting it out saves 8 bytes.  This
-** is only a savings of 0.8% but those percentages add up.
-*/
-typedef struct PgHistory PgHistory;
-struct PgHistory {
-  u8 *pOrig;     /* Original page text.  Restore to this on a full rollback */
-  u8 *pStmt;     /* Text as it was at the beginning of the current statement */
-  PgHdr *pNextStmt, *pPrevStmt;  /* List of pages in the statement journal */
-  u8 inStmt;                     /* TRUE if in the statement subjournal */
-};
-
-/*
-** A macro used for invoking the codec if there is one
+** Here is an interesting observation:  Win95, Win98, and WinME lack
+** the LockFileEx() API.  But we can still statically link against that
+** API as long as we don't call it when running Win95/98/ME.  A call to
+** this routine is used to determine if the host is Win95/98/ME or
+** WinNT/2K/XP so that we will know whether or not we can safely call
+** the LockFileEx() API.
 */
-#ifdef SQLITE_HAS_CODEC
-# define CODEC1(P,D,N,X) if( P->xCodec!=0 ){ P->xCodec(P->pCodecArg,D,N,X); }
-# define CODEC2(P,D,N,X) ((char*)(P->xCodec!=0?P->xCodec(P->pCodecArg,D,N,X):D))
+#if SQLITE_OS_WINCE
+# define isNT()  (1)
 #else
-# define CODEC1(P,D,N,X) /* NO-OP */
-# define CODEC2(P,D,N,X) ((char*)D)
-#endif
-
-/*
-** Convert a pointer to a PgHdr into a pointer to its data
-** and back again.
-*/
-#define PGHDR_TO_DATA(P)    ((P)->pData)
-#define PGHDR_TO_EXTRA(G,P) ((void*)&((G)[1]))
-#define PGHDR_TO_HIST(P,PGR)  \
-            ((PgHistory*)&((char*)(&(P)[1]))[(PGR)->nExtra])
+  static int isNT(void){
+    if( sqlite3_os_type==0 ){
+      OSVERSIONINFO sInfo;
+      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+      GetVersionEx(&sInfo);
+      sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
+    }
+    return sqlite3_os_type==2;
+  }
+#endif /* SQLITE_OS_WINCE */
 
 /*
-** A open page cache is an instance of the following structure.
+** Convert a UTF-8 string to microsoft unicode (UTF-16?). 
 **
-** Pager.errCode may be set to SQLITE_IOERR, SQLITE_CORRUPT, or
-** or SQLITE_FULL. Once one of the first three errors occurs, it persists
-** and is returned as the result of every major pager API call.  The
-** SQLITE_FULL return code is slightly different. It persists only until the
-** next successful rollback is performed on the pager cache. Also,
-** SQLITE_FULL does not affect the sqlite3PagerGet() and sqlite3PagerLookup()
-** APIs, they may still be used successfully.
+** Space to hold the returned string is obtained from malloc.
 */
-struct Pager {
-  sqlite3_vfs *pVfs;          /* OS functions to use for IO */
-  u8 journalOpen;             /* True if journal file descriptors is valid */
-  u8 journalStarted;          /* True if header of journal is synced */
-  u8 useJournal;              /* Use a rollback journal on this file */
-  u8 noReadlock;              /* Do not bother to obtain readlocks */
-  u8 stmtOpen;                /* True if the statement subjournal is open */
-  u8 stmtInUse;               /* True we are in a statement subtransaction */
-  u8 stmtAutoopen;            /* Open stmt journal when main journal is opened*/
-  u8 noSync;                  /* Do not sync the journal if true */
-  u8 fullSync;                /* Do extra syncs of the journal for robustness */
-  u8 sync_flags;              /* One of SYNC_NORMAL or SYNC_FULL */
-  u8 state;                   /* PAGER_UNLOCK, _SHARED, _RESERVED, etc. */
-  u8 tempFile;                /* zFilename is a temporary file */
-  u8 readOnly;                /* True for a read-only database */
-  u8 needSync;                /* True if an fsync() is needed on the journal */
-  u8 dirtyCache;              /* True if cached pages have changed */
-  u8 alwaysRollback;          /* Disable DontRollback() for all pages */
-  u8 memDb;                   /* True to inhibit all file I/O */
-  u8 setMaster;               /* True if a m-j name has been written to jrnl */
-  u8 doNotSync;               /* Boolean. While true, do not spill the cache */
-  u8 exclusiveMode;           /* Boolean. True if locking_mode==EXCLUSIVE */
-  u8 journalMode;             /* On of the PAGER_JOURNALMODE_* values */
-  u8 dbModified;              /* True if there are any changes to the Db */
-  u8 changeCountDone;         /* Set after incrementing the change-counter */
-  u32 vfsFlags;               /* Flags for sqlite3_vfs.xOpen() */
-  int errCode;                /* One of several kinds of errors */
-  int dbSize;                 /* Number of pages in the file */
-  int origDbSize;             /* dbSize before the current change */
-  int stmtSize;               /* Size of database (in pages) at stmt_begin() */
-  int nRec;                   /* Number of pages written to the journal */
-  u32 cksumInit;              /* Quasi-random value added to every checksum */
-  int stmtNRec;               /* Number of records in stmt subjournal */
-  int nExtra;                 /* Add this many bytes to each in-memory page */
-  int pageSize;               /* Number of bytes in a page */
-  int nPage;                  /* Total number of in-memory pages */
-  int nRef;                   /* Number of in-memory pages with PgHdr.nRef>0 */
-  int mxPage;                 /* Maximum number of pages to hold in cache */
-  Pgno mxPgno;                /* Maximum allowed size of the database */
-  Bitvec *pInJournal;         /* One bit for each page in the database file */
-  Bitvec *pInStmt;            /* One bit for each page in the database */
-  char *zFilename;            /* Name of the database file */
-  char *zJournal;             /* Name of the journal file */
-  char *zDirectory;           /* Directory hold database and journal files */
-  char *zStmtJrnl;            /* Name of the statement journal file */
-  sqlite3_file *fd, *jfd;     /* File descriptors for database and journal */
-  sqlite3_file *stfd;         /* File descriptor for the statement subjournal*/
-  BusyHandler *pBusyHandler;  /* Pointer to sqlite.busyHandler */
-  PagerLruList lru;           /* LRU list of free pages */
-  PgHdr *pAll;                /* List of all pages */
-  PgHdr *pStmt;               /* List of pages in the statement subjournal */
-  PgHdr *pDirty;              /* List of all dirty pages */
-  i64 journalOff;             /* Current byte offset in the journal file */
-  i64 journalHdr;             /* Byte offset to previous journal header */
-  i64 stmtHdrOff;             /* First journal header written this statement */
-  i64 stmtCksum;              /* cksumInit when statement was started */
-  i64 stmtJSize;              /* Size of journal at stmt_begin() */
-  int sectorSize;             /* Assumed sector size during rollback */
-#ifdef SQLITE_TEST
-  int nHit, nMiss;            /* Cache hits and missing */
-  int nRead, nWrite;          /* Database pages read/written */
-#endif
-  void (*xDestructor)(DbPage*,int); /* Call this routine when freeing pages */
-  void (*xReiniter)(DbPage*,int);   /* Call this routine when reloading pages */
-#ifdef SQLITE_HAS_CODEC
-  void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
-  void *pCodecArg;            /* First argument to xCodec() */
-#endif
-  int nHash;                  /* Size of the pager hash table */
-  PgHdr **aHash;              /* Hash table to map page number to PgHdr */
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  Pager *pNext;               /* Doubly linked list of pagers on which */
-  Pager *pPrev;               /* sqlite3_release_memory() will work */
-  int iInUseMM;               /* Non-zero if unavailable to MM */
-  int iInUseDB;               /* Non-zero if in sqlite3_release_memory() */
-#endif
-  char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
-  char dbFileVers[16];        /* Changes whenever database file changes */
-};
+static WCHAR *utf8ToUnicode(const char *zFilename){
+  int nChar;
+  WCHAR *zWideFilename;
+
+  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
+  zWideFilename = malloc( nChar*sizeof(zWideFilename[0]) );
+  if( zWideFilename==0 ){
+    return 0;
+  }
+  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar);
+  if( nChar==0 ){
+    free(zWideFilename);
+    zWideFilename = 0;
+  }
+  return zWideFilename;
+}
 
 /*
-** The following global variables hold counters used for
-** testing purposes only.  These variables do not exist in
-** a non-testing build.  These variables are not thread-safe.
+** Convert microsoft unicode to UTF-8.  Space to hold the returned string is
+** obtained from malloc().
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_pager_readdb_count = 0;    /* Number of full pages read from DB */
-SQLITE_API int sqlite3_pager_writedb_count = 0;   /* Number of full pages written to DB */
-SQLITE_API int sqlite3_pager_writej_count = 0;    /* Number of pages written to journal */
-SQLITE_API int sqlite3_pager_pgfree_count = 0;    /* Number of cache pages freed */
-# define PAGER_INCR(v)  v++
-#else
-# define PAGER_INCR(v)
-#endif
+static char *unicodeToUtf8(const WCHAR *zWideFilename){
+  int nByte;
+  char *zFilename;
+
+  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
+  zFilename = malloc( nByte );
+  if( zFilename==0 ){
+    return 0;
+  }
+  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
+                              0, 0);
+  if( nByte == 0 ){
+    free(zFilename);
+    zFilename = 0;
+  }
+  return zFilename;
+}
 
 /*
-** The following variable points to the head of a double-linked list
-** of all pagers that are eligible for page stealing by the
-** sqlite3_release_memory() interface.  Access to this list is
-** protected by the SQLITE_MUTEX_STATIC_MEM2 mutex.
+** Convert an ansi string to microsoft unicode, based on the
+** current codepage settings for file apis.
+** 
+** Space to hold the returned string is obtained
+** from malloc.
 */
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-static Pager *sqlite3PagerList = 0;
-static PagerLruList sqlite3LruPageList = {0, 0, 0};
-#endif
+static WCHAR *mbcsToUnicode(const char *zFilename){
+  int nByte;
+  WCHAR *zMbcsFilename;
+  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;
 
+  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR);
+  zMbcsFilename = malloc( nByte*sizeof(zMbcsFilename[0]) );
+  if( zMbcsFilename==0 ){
+    return 0;
+  }
+  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte);
+  if( nByte==0 ){
+    free(zMbcsFilename);
+    zMbcsFilename = 0;
+  }
+  return zMbcsFilename;
+}
 
 /*
-** Journal files begin with the following magic string.  The data
-** was obtained from /dev/random.  It is used only as a sanity check.
-**
-** Since version 2.8.0, the journal format contains additional sanity
-** checking information.  If the power fails while the journal is begin
-** written, semi-random garbage data might appear in the journal
-** file after power is restored.  If an attempt is then made
-** to roll the journal back, the database could be corrupted.  The additional
-** sanity checking data is an attempt to discover the garbage in the
-** journal and ignore it.
+** Convert microsoft unicode to multibyte character string, based on the
+** user's Ansi codepage.
 **
-** The sanity checking information for the new journal format consists
-** of a 32-bit checksum on each page of data.  The checksum covers both
-** the page number and the pPager->pageSize bytes of data for the page.
-** This cksum is initialized to a 32-bit random value that appears in the
-** journal file right after the header.  The random initializer is important,
-** because garbage data that appears at the end of a journal is likely
-** data that was once in other files that have now been deleted.  If the
-** garbage data came from an obsolete journal file, the checksums might
-** be correct.  But by initializing the checksum to random value which
-** is different for every journal, we minimize that risk.
+** Space to hold the returned string is obtained from
+** malloc().
 */
-static const unsigned char aJournalMagic[] = {
-  0xd9, 0xd5, 0x05, 0xf9, 0x20, 0xa1, 0x63, 0xd7,
-};
+static char *unicodeToMbcs(const WCHAR *zWideFilename){
+  int nByte;
+  char *zFilename;
+  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;
 
-/*
-** The size of the header and of each page in the journal is determined
-** by the following macros.
-*/
-#define JOURNAL_PG_SZ(pPager)  ((pPager->pageSize) + 8)
+  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
+  zFilename = malloc( nByte );
+  if( zFilename==0 ){
+    return 0;
+  }
+  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte,
+                              0, 0);
+  if( nByte == 0 ){
+    free(zFilename);
+    zFilename = 0;
+  }
+  return zFilename;
+}
 
 /*
-** The journal header size for this pager. In the future, this could be
-** set to some value read from the disk controller. The important
-** characteristic is that it is the same size as a disk sector.
+** Convert multibyte character string to UTF-8.  Space to hold the
+** returned string is obtained from malloc().
 */
-#define JOURNAL_HDR_SZ(pPager) (pPager->sectorSize)
+SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
+  char *zFilenameUtf8;
+  WCHAR *zTmpWide;
+
+  zTmpWide = mbcsToUnicode(zFilename);
+  if( zTmpWide==0 ){
+    return 0;
+  }
+  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
+  free(zTmpWide);
+  return zFilenameUtf8;
+}
 
 /*
-** The macro MEMDB is true if we are dealing with an in-memory database.
-** We do this as a macro so that if the SQLITE_OMIT_MEMORYDB macro is set,
-** the value of MEMDB will be a constant and the compiler will optimize
-** out code that would never execute.
+** Convert UTF-8 to multibyte character string.  Space to hold the 
+** returned string is obtained from malloc().
 */
-#ifdef SQLITE_OMIT_MEMORYDB
-# define MEMDB 0
-#else
-# define MEMDB pPager->memDb
-#endif
+static char *utf8ToMbcs(const char *zFilename){
+  char *zFilenameMbcs;
+  WCHAR *zTmpWide;
+
+  zTmpWide = utf8ToUnicode(zFilename);
+  if( zTmpWide==0 ){
+    return 0;
+  }
+  zFilenameMbcs = unicodeToMbcs(zTmpWide);
+  free(zTmpWide);
+  return zFilenameMbcs;
+}
 
+#if SQLITE_OS_WINCE
+/*************************************************************************
+** This section contains code for WinCE only.
+*/
 /*
-** Page number PAGER_MJ_PGNO is never used in an SQLite database (it is
-** reserved for working around a windows/posix incompatibility). It is
-** used in the journal to signify that the remainder of the journal file 
-** is devoted to storing a master journal name - there are no more pages to
-** roll back. See comments for function writeMasterJournal() for details.
+** WindowsCE does not have a localtime() function.  So create a
+** substitute.
 */
-/* #define PAGER_MJ_PGNO(x) (PENDING_BYTE/((x)->pageSize)) */
-#define PAGER_MJ_PGNO(x) ((PENDING_BYTE/((x)->pageSize))+1)
+struct tm *__cdecl localtime(const time_t *t)
+{
+  static struct tm y;
+  FILETIME uTm, lTm;
+  SYSTEMTIME pTm;
+  sqlite3_int64 t64;
+  t64 = *t;
+  t64 = (t64 + 11644473600)*10000000;
+  uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
+  uTm.dwHighDateTime= (DWORD)(t64 >> 32);
+  FileTimeToLocalFileTime(&uTm,&lTm);
+  FileTimeToSystemTime(&lTm,&pTm);
+  y.tm_year = pTm.wYear - 1900;
+  y.tm_mon = pTm.wMonth - 1;
+  y.tm_wday = pTm.wDayOfWeek;
+  y.tm_mday = pTm.wDay;
+  y.tm_hour = pTm.wHour;
+  y.tm_min = pTm.wMinute;
+  y.tm_sec = pTm.wSecond;
+  return &y;
+}
+
+/* This will never be called, but defined to make the code compile */
+#define GetTempPathA(a,b)
+
+#define LockFile(a,b,c,d,e)       winceLockFile(&a, b, c, d, e)
+#define UnlockFile(a,b,c,d,e)     winceUnlockFile(&a, b, c, d, e)
+#define LockFileEx(a,b,c,d,e,f)   winceLockFileEx(&a, b, c, d, e, f)
+
+#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
 
 /*
-** The maximum legal page number is (2^31 - 1).
+** Acquire a lock on the handle h
 */
-#define PAGER_MAX_PGNO 2147483647
-
+static void winceMutexAcquire(HANDLE h){
+   DWORD dwErr;
+   do {
+     dwErr = WaitForSingleObject(h, INFINITE);
+   } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
+}
 /*
-** The pagerEnter() and pagerLeave() routines acquire and release
-** a mutex on each pager.  The mutex is recursive.
-**
-** This is a special-purpose mutex.  It only provides mutual exclusion
-** between the Btree and the Memory Management sqlite3_release_memory()
-** function.  It does not prevent, for example, two Btrees from accessing
-** the same pager at the same time.  Other general-purpose mutexes in
-** the btree layer handle that chore.
+** Release a lock acquired by winceMutexAcquire()
 */
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  static void pagerEnter(Pager *p){
-    p->iInUseDB++;
-    if( p->iInUseMM && p->iInUseDB==1 ){
-#ifndef SQLITE_MUTEX_NOOP
-      sqlite3_mutex *mutex;
-      mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM2);
-#endif
-      p->iInUseDB = 0;
-      sqlite3_mutex_enter(mutex);
-      p->iInUseDB = 1;
-      sqlite3_mutex_leave(mutex);
-    }
-    assert( p->iInUseMM==0 );
-  }
-  static void pagerLeave(Pager *p){
-    p->iInUseDB--;
-    assert( p->iInUseDB>=0 );
-  }
-#else
-# define pagerEnter(X)
-# define pagerLeave(X)
-#endif
+#define winceMutexRelease(h) ReleaseMutex(h)
 
 /*
-** Add page pPg to the end of the linked list managed by structure
-** pList (pPg becomes the last entry in the list - the most recently 
-** used). Argument pLink should point to either pPg->free or pPg->gfree,
-** depending on whether pPg is being added to the pager-specific or
-** global LRU list.
+** Create the mutex and shared memory used for locking in the file
+** descriptor pFile
 */
-static void listAdd(PagerLruList *pList, PagerLruLink *pLink, PgHdr *pPg){
-  pLink->pNext = 0;
-  pLink->pPrev = pList->pLast;
+static BOOL winceCreateLock(const char *zFilename, winFile *pFile){
+  WCHAR *zTok;
+  WCHAR *zName = utf8ToUnicode(zFilename);
+  BOOL bInit = TRUE;
 
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  assert(pLink==&pPg->free || pLink==&pPg->gfree);
-  assert(pLink==&pPg->gfree || pList!=&sqlite3LruPageList);
-#endif
+  /* Initialize the local lockdata */
+  ZeroMemory(&pFile->local, sizeof(pFile->local));
 
-  if( pList->pLast ){
-    int iOff = (char *)pLink - (char *)pPg;
-    PagerLruLink *pLastLink = (PagerLruLink *)(&((u8 *)pList->pLast)[iOff]);
-    pLastLink->pNext = pPg;
-  }else{
-    assert(!pList->pFirst);
-    pList->pFirst = pPg;
+  /* Replace the backslashes from the filename and lowercase it
+  ** to derive a mutex name. */
+  zTok = CharLowerW(zName);
+  for (;*zTok;zTok++){
+    if (*zTok == '\\') *zTok = '_';
   }
 
-  pList->pLast = pPg;
-  if( !pList->pFirstSynced && pPg->needSync==0 ){
-    pList->pFirstSynced = pPg;
+  /* Create/open the named mutex */
+  pFile->hMutex = CreateMutexW(NULL, FALSE, zName);
+  if (!pFile->hMutex){
+    pFile->lastErrno = GetLastError();
+    free(zName);
+    return FALSE;
   }
-}
-
-/*
-** Remove pPg from the list managed by the structure pointed to by pList.
-**
-** Argument pLink should point to either pPg->free or pPg->gfree, depending 
-** on whether pPg is being added to the pager-specific or global LRU list.
-*/
-static void listRemove(PagerLruList *pList, PagerLruLink *pLink, PgHdr *pPg){
-  int iOff = (char *)pLink - (char *)pPg;
 
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  assert(pLink==&pPg->free || pLink==&pPg->gfree);
-  assert(pLink==&pPg->gfree || pList!=&sqlite3LruPageList);
-#endif
+  /* Acquire the mutex before continuing */
+  winceMutexAcquire(pFile->hMutex);
+  
+  /* Since the names of named mutexes, semaphores, file mappings etc are 
+  ** case-sensitive, take advantage of that by uppercasing the mutex name
+  ** and using that as the shared filemapping name.
+  */
+  CharUpperW(zName);
+  pFile->hShared = CreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
+                                       PAGE_READWRITE, 0, sizeof(winceLock),
+                                       zName);  
 
-  if( pPg==pList->pFirst ){
-    pList->pFirst = pLink->pNext;
-  }
-  if( pPg==pList->pLast ){
-    pList->pLast = pLink->pPrev;
+  /* Set a flag that indicates we're the first to create the memory so it 
+  ** must be zero-initialized */
+  if (GetLastError() == ERROR_ALREADY_EXISTS){
+    bInit = FALSE;
   }
-  if( pLink->pPrev ){
-    PagerLruLink *pPrevLink = (PagerLruLink *)(&((u8 *)pLink->pPrev)[iOff]);
-    pPrevLink->pNext = pLink->pNext;
+
+  free(zName);
+
+  /* If we succeeded in making the shared memory handle, map it. */
+  if (pFile->hShared){
+    pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, 
+             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
+    /* If mapping failed, close the shared memory handle and erase it */
+    if (!pFile->shared){
+      pFile->lastErrno = GetLastError();
+      CloseHandle(pFile->hShared);
+      pFile->hShared = NULL;
+    }
   }
-  if( pLink->pNext ){
-    PagerLruLink *pNextLink = (PagerLruLink *)(&((u8 *)pLink->pNext)[iOff]);
-    pNextLink->pPrev = pLink->pPrev;
+
+  /* If shared memory could not be created, then close the mutex and fail */
+  if (pFile->hShared == NULL){
+    winceMutexRelease(pFile->hMutex);
+    CloseHandle(pFile->hMutex);
+    pFile->hMutex = NULL;
+    return FALSE;
   }
-  if( pPg==pList->pFirstSynced ){
-    PgHdr *p = pLink->pNext;
-    while( p && p->needSync ){
-      PagerLruLink *pL = (PagerLruLink *)(&((u8 *)p)[iOff]);
-      p = pL->pNext;
-    }
-    pList->pFirstSynced = p;
+  
+  /* Initialize the shared memory if we're supposed to */
+  if (bInit) {
+    ZeroMemory(pFile->shared, sizeof(winceLock));
   }
 
-  pLink->pNext = pLink->pPrev = 0;
+  winceMutexRelease(pFile->hMutex);
+  return TRUE;
 }
 
-/* 
-** Add page pPg to the list of free pages for the pager. If 
-** memory-management is enabled, also add the page to the global 
-** list of free pages.
+/*
+** Destroy the part of winFile that deals with wince locks
 */
-static void lruListAdd(PgHdr *pPg){
-  listAdd(&pPg->pPager->lru, &pPg->free, pPg);
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  if( !pPg->pPager->memDb ){
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-    listAdd(&sqlite3LruPageList, &pPg->gfree, pPg);
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
+static void winceDestroyLock(winFile *pFile){
+  if (pFile->hMutex){
+    /* Acquire the mutex */
+    winceMutexAcquire(pFile->hMutex);
+
+    /* The following blocks should probably assert in debug mode, but they
+       are to cleanup in case any locks remained open */
+    if (pFile->local.nReaders){
+      pFile->shared->nReaders --;
+    }
+    if (pFile->local.bReserved){
+      pFile->shared->bReserved = FALSE;
+    }
+    if (pFile->local.bPending){
+      pFile->shared->bPending = FALSE;
+    }
+    if (pFile->local.bExclusive){
+      pFile->shared->bExclusive = FALSE;
+    }
+
+    /* De-reference and close our copy of the shared memory handle */
+    UnmapViewOfFile(pFile->shared);
+    CloseHandle(pFile->hShared);
+
+    /* Done with the mutex */
+    winceMutexRelease(pFile->hMutex);    
+    CloseHandle(pFile->hMutex);
+    pFile->hMutex = NULL;
   }
-#endif
 }
 
 /* 
-** Remove page pPg from the list of free pages for the associated pager.
-** If memory-management is enabled, also remove pPg from the global list
-** of free pages.
+** An implementation of the LockFile() API of windows for wince
 */
-static void lruListRemove(PgHdr *pPg){
-  listRemove(&pPg->pPager->lru, &pPg->free, pPg);
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  if( !pPg->pPager->memDb ){
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-    listRemove(&sqlite3LruPageList, &pPg->gfree, pPg);
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-  }
-#endif
-}
+static BOOL winceLockFile(
+  HANDLE *phFile,
+  DWORD dwFileOffsetLow,
+  DWORD dwFileOffsetHigh,
+  DWORD nNumberOfBytesToLockLow,
+  DWORD nNumberOfBytesToLockHigh
+){
+  winFile *pFile = HANDLE_TO_WINFILE(phFile);
+  BOOL bReturn = FALSE;
 
-/* 
-** This function is called just after the needSync flag has been cleared
-** from all pages managed by pPager (usually because the journal file
-** has just been synced). It updates the pPager->lru.pFirstSynced variable
-** and, if memory-management is enabled, the sqlite3LruPageList.pFirstSynced
-** variable also.
-*/
-static void lruListSetFirstSynced(Pager *pPager){
-  pPager->lru.pFirstSynced = pPager->lru.pFirst;
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  if( !pPager->memDb ){
-    PgHdr *p;
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-    for(p=sqlite3LruPageList.pFirst; p && p->needSync; p=p->gfree.pNext);
-    assert(p==pPager->lru.pFirstSynced || p==sqlite3LruPageList.pFirstSynced);
-    sqlite3LruPageList.pFirstSynced = p;
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-  }
-#endif
-}
+  UNUSED_PARAMETER(dwFileOffsetHigh);
+  UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
 
-/*
-** Return true if page *pPg has already been written to the statement
-** journal (or statement snapshot has been created, if *pPg is part
-** of an in-memory database).
-*/
-static int pageInStatement(PgHdr *pPg){
-  Pager *pPager = pPg->pPager;
-  if( MEMDB ){
-    return PGHDR_TO_HIST(pPg, pPager)->inStmt;
-  }else{
-    return sqlite3BitvecTest(pPager->pInStmt, pPg->pgno);
-  }
-}
+  if (!pFile->hMutex) return TRUE;
+  winceMutexAcquire(pFile->hMutex);
 
-/*
-** Change the size of the pager hash table to N.  N must be a power
-** of two.
-*/
-static void pager_resize_hash_table(Pager *pPager, int N){
-  PgHdr **aHash, *pPg;
-  assert( N>0 && (N&(N-1))==0 );
-#ifdef SQLITE_MALLOC_SOFT_LIMIT
-  if( N*sizeof(aHash[0])>SQLITE_MALLOC_SOFT_LIMIT ){
-    N = SQLITE_MALLOC_SOFT_LIMIT/sizeof(aHash[0]);
-  }
-  if( N==pPager->nHash ) return;
-#endif
-  pagerLeave(pPager);
-  if( pPager->aHash!=0 ) sqlite3FaultBeginBenign(SQLITE_FAULTINJECTOR_MALLOC);
-  aHash = sqlite3MallocZero( sizeof(aHash[0])*N );
-  if( pPager->aHash!=0 ) sqlite3FaultEndBenign(SQLITE_FAULTINJECTOR_MALLOC);
-  pagerEnter(pPager);
-  if( aHash==0 ){
-    /* Failure to rehash is not an error.  It is only a performance hit. */
-    return;
+  /* Wanting an exclusive lock? */
+  if (dwFileOffsetLow == (DWORD)SHARED_FIRST
+       && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
+    if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
+       pFile->shared->bExclusive = TRUE;
+       pFile->local.bExclusive = TRUE;
+       bReturn = TRUE;
+    }
   }
-  sqlite3_free(pPager->aHash);
-  pPager->nHash = N;
-  pPager->aHash = aHash;
-  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-    int h;
-    if( pPg->pgno==0 ){
-      assert( pPg->pNextHash==0 && pPg->pPrevHash==0 );
-      continue;
+
+  /* Want a read-only lock? */
+  else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
+           nNumberOfBytesToLockLow == 1){
+    if (pFile->shared->bExclusive == 0){
+      pFile->local.nReaders ++;
+      if (pFile->local.nReaders == 1){
+        pFile->shared->nReaders ++;
+      }
+      bReturn = TRUE;
     }
-    h = pPg->pgno & (N-1);
-    pPg->pNextHash = aHash[h];
-    if( aHash[h] ){
-      aHash[h]->pPrevHash = pPg;
+  }
+
+  /* Want a pending lock? */
+  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToLockLow == 1){
+    /* If no pending lock has been acquired, then acquire it */
+    if (pFile->shared->bPending == 0) {
+      pFile->shared->bPending = TRUE;
+      pFile->local.bPending = TRUE;
+      bReturn = TRUE;
     }
-    aHash[h] = pPg;
-    pPg->pPrevHash = 0;
   }
-}
 
-/*
-** Read a 32-bit integer from the given file descriptor.  Store the integer
-** that is read in *pRes.  Return SQLITE_OK if everything worked, or an
-** error code is something goes wrong.
-**
-** All values are stored on disk as big-endian.
-*/
-static int read32bits(sqlite3_file *fd, i64 offset, u32 *pRes){
-  unsigned char ac[4];
-  int rc = sqlite3OsRead(fd, ac, sizeof(ac), offset);
-  if( rc==SQLITE_OK ){
-    *pRes = sqlite3Get4byte(ac);
+  /* Want a reserved lock? */
+  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToLockLow == 1){
+    if (pFile->shared->bReserved == 0) {
+      pFile->shared->bReserved = TRUE;
+      pFile->local.bReserved = TRUE;
+      bReturn = TRUE;
+    }
   }
-  return rc;
+
+  winceMutexRelease(pFile->hMutex);
+  return bReturn;
 }
 
 /*
-** Write a 32-bit integer into a string buffer in big-endian byte order.
+** An implementation of the UnlockFile API of windows for wince
 */
-#define put32bits(A,B)  sqlite3Put4byte((u8*)A,B)
+static BOOL winceUnlockFile(
+  HANDLE *phFile,
+  DWORD dwFileOffsetLow,
+  DWORD dwFileOffsetHigh,
+  DWORD nNumberOfBytesToUnlockLow,
+  DWORD nNumberOfBytesToUnlockHigh
+){
+  winFile *pFile = HANDLE_TO_WINFILE(phFile);
+  BOOL bReturn = FALSE;
 
-/*
-** Write a 32-bit integer into the given file descriptor.  Return SQLITE_OK
-** on success or an error code is something goes wrong.
-*/
-static int write32bits(sqlite3_file *fd, i64 offset, u32 val){
-  char ac[4];
-  put32bits(ac, val);
-  return sqlite3OsWrite(fd, ac, 4, offset);
-}
+  UNUSED_PARAMETER(dwFileOffsetHigh);
+  UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
 
-/*
-** If file pFd is open, call sqlite3OsUnlock() on it.
-*/
-static int osUnlock(sqlite3_file *pFd, int eLock){
-  if( !pFd->pMethods ){
-    return SQLITE_OK;
-  }
-  return sqlite3OsUnlock(pFd, eLock);
-}
+  if (!pFile->hMutex) return TRUE;
+  winceMutexAcquire(pFile->hMutex);
 
-/*
-** This function determines whether or not the atomic-write optimization
-** can be used with this pager. The optimization can be used if:
-**
-**  (a) the value returned by OsDeviceCharacteristics() indicates that
-**      a database page may be written atomically, and
-**  (b) the value returned by OsSectorSize() is less than or equal
-**      to the page size.
-**
-** If the optimization cannot be used, 0 is returned. If it can be used,
-** then the value returned is the size of the journal file when it
-** contains rollback data for exactly one page.
-*/
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-static int jrnlBufferSize(Pager *pPager){
-  int dc;           /* Device characteristics */
-  int nSector;      /* Sector size */
-  int nPage;        /* Page size */
-  sqlite3_file *fd = pPager->fd;
+  /* Releasing a reader lock or an exclusive lock */
+  if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
+    /* Did we have an exclusive lock? */
+    if (pFile->local.bExclusive){
+      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
+      pFile->local.bExclusive = FALSE;
+      pFile->shared->bExclusive = FALSE;
+      bReturn = TRUE;
+    }
 
-  if( fd->pMethods ){
-    dc = sqlite3OsDeviceCharacteristics(fd);
-    nSector = sqlite3OsSectorSize(fd);
-    nPage = pPager->pageSize;
+    /* Did we just have a reader lock? */
+    else if (pFile->local.nReaders){
+      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE || nNumberOfBytesToUnlockLow == 1);
+      pFile->local.nReaders --;
+      if (pFile->local.nReaders == 0)
+      {
+        pFile->shared->nReaders --;
+      }
+      bReturn = TRUE;
+    }
   }
 
-  assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
-  assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
-
-  if( !fd->pMethods || (dc&(SQLITE_IOCAP_ATOMIC|(nPage>>8))&&nSector<=nPage) ){
-    return JOURNAL_HDR_SZ(pPager) + JOURNAL_PG_SZ(pPager);
+  /* Releasing a pending lock */
+  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToUnlockLow == 1){
+    if (pFile->local.bPending){
+      pFile->local.bPending = FALSE;
+      pFile->shared->bPending = FALSE;
+      bReturn = TRUE;
+    }
   }
-  return 0;
-}
-#endif
-
-/*
-** This function should be called when an error occurs within the pager
-** code. The first argument is a pointer to the pager structure, the
-** second the error-code about to be returned by a pager API function. 
-** The value returned is a copy of the second argument to this function. 
-**
-** If the second argument is SQLITE_IOERR, SQLITE_CORRUPT, or SQLITE_FULL
-** the error becomes persistent. Until the persisten error is cleared,
-** subsequent API calls on this Pager will immediately return the same 
-** error code.
-**
-** A persistent error indicates that the contents of the pager-cache 
-** cannot be trusted. This state can be cleared by completely discarding 
-** the contents of the pager-cache. If a transaction was active when
-** the persistent error occured, then the rollback journal may need
-** to be replayed.
-*/
-static void pager_unlock(Pager *pPager);
-static int pager_error(Pager *pPager, int rc){
-  int rc2 = rc & 0xff;
-  assert(
-       pPager->errCode==SQLITE_FULL ||
-       pPager->errCode==SQLITE_OK ||
-       (pPager->errCode & 0xff)==SQLITE_IOERR
-  );
-  if(
-    rc2==SQLITE_FULL ||
-    rc2==SQLITE_IOERR ||
-    rc2==SQLITE_CORRUPT
-  ){
-    pPager->errCode = rc;
-    if( pPager->state==PAGER_UNLOCK && pPager->nRef==0 ){
-      /* If the pager is already unlocked, call pager_unlock() now to
-      ** clear the error state and ensure that the pager-cache is 
-      ** completely empty.
-      */
-      pager_unlock(pPager);
+  /* Releasing a reserved lock */
+  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToUnlockLow == 1){
+    if (pFile->local.bReserved) {
+      pFile->local.bReserved = FALSE;
+      pFile->shared->bReserved = FALSE;
+      bReturn = TRUE;
     }
   }
-  return rc;
+
+  winceMutexRelease(pFile->hMutex);
+  return bReturn;
 }
 
 /*
-** If SQLITE_CHECK_PAGES is defined then we do some sanity checking
-** on the cache using a hash function.  This is used for testing
-** and debugging only.
-*/
-#ifdef SQLITE_CHECK_PAGES
-/*
-** Return a 32-bit hash of the page data for pPage.
+** An implementation of the LockFileEx() API of windows for wince
 */
-static u32 pager_datahash(int nByte, unsigned char *pData){
-  u32 hash = 0;
-  int i;
-  for(i=0; i<nByte; i++){
-    hash = (hash*1039) + pData[i];
+static BOOL winceLockFileEx(
+  HANDLE *phFile,
+  DWORD dwFlags,
+  DWORD dwReserved,
+  DWORD nNumberOfBytesToLockLow,
+  DWORD nNumberOfBytesToLockHigh,
+  LPOVERLAPPED lpOverlapped
+){
+  UNUSED_PARAMETER(dwReserved);
+  UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
+
+  /* If the caller wants a shared read lock, forward this call
+  ** to winceLockFile */
+  if (lpOverlapped->Offset == (DWORD)SHARED_FIRST &&
+      dwFlags == 1 &&
+      nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
+    return winceLockFile(phFile, SHARED_FIRST, 0, 1, 0);
   }
-  return hash;
-}
-static u32 pager_pagehash(PgHdr *pPage){
-  return pager_datahash(pPage->pPager->pageSize, 
-                        (unsigned char *)PGHDR_TO_DATA(pPage));
+  return FALSE;
 }
-
 /*
-** The CHECK_PAGE macro takes a PgHdr* as an argument. If SQLITE_CHECK_PAGES
-** is defined, and NDEBUG is not defined, an assert() statement checks
-** that the page is either dirty or still matches the calculated page-hash.
-*/
-#define CHECK_PAGE(x) checkPage(x)
-static void checkPage(PgHdr *pPg){
-  Pager *pPager = pPg->pPager;
-  assert( !pPg->pageHash || pPager->errCode || MEMDB || pPg->dirty || 
-      pPg->pageHash==pager_pagehash(pPg) );
-}
+** End of the special code for wince
+*****************************************************************************/
+#endif /* SQLITE_OS_WINCE */
 
-#else
-#define pager_datahash(X,Y)  0
-#define pager_pagehash(X)  0
-#define CHECK_PAGE(x)
-#endif
+/*****************************************************************************
+** The next group of routines implement the I/O methods specified
+** by the sqlite3_io_methods object.
+******************************************************************************/
 
 /*
-** When this is called the journal file for pager pPager must be open.
-** The master journal file name is read from the end of the file and 
-** written into memory supplied by the caller. 
-**
-** zMaster must point to a buffer of at least nMaster bytes allocated by
-** the caller. This should be sqlite3_vfs.mxPathname+1 (to ensure there is
-** enough space to write the master journal name). If the master journal
-** name in the journal is longer than nMaster bytes (including a
-** nul-terminator), then this is handled as if no master journal name
-** were present in the journal.
+** Close a file.
 **
-** If no master journal file name is present zMaster[0] is set to 0 and
-** SQLITE_OK returned.
+** It is reported that an attempt to close a handle might sometimes
+** fail.  This is a very unreasonable result, but windows is notorious
+** for being unreasonable so I do not doubt that it might happen.  If
+** the close fails, we pause for 100 milliseconds and try again.  As
+** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
+** giving up and returning an error.
 */
-static int readMasterJournal(sqlite3_file *pJrnl, char *zMaster, int nMaster){
-  int rc;
-  u32 len;
-  i64 szJ;
-  u32 cksum;
-  int i;
-  unsigned char aMagic[8]; /* A buffer to hold the magic header */
-
-  zMaster[0] = '\0';
-
-  rc = sqlite3OsFileSize(pJrnl, &szJ);
-  if( rc!=SQLITE_OK || szJ<16 ) return rc;
-
-  rc = read32bits(pJrnl, szJ-16, &len);
-  if( rc!=SQLITE_OK ) return rc;
-
-  if( len>=nMaster ){
-    return SQLITE_OK;
-  }
-
-  rc = read32bits(pJrnl, szJ-12, &cksum);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8);
-  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, 8) ) return rc;
-
-  rc = sqlite3OsRead(pJrnl, zMaster, len, szJ-16-len);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  zMaster[len] = '\0';
+#define MX_CLOSE_ATTEMPT 3
+static int winClose(sqlite3_file *id){
+  int rc, cnt = 0;
+  winFile *pFile = (winFile*)id;
 
-  /* See if the checksum matches the master journal name */
-  for(i=0; i<len; i++){
-    cksum -= zMaster[i];
-   }
-  if( cksum ){
-    /* If the checksum doesn't add up, then one or more of the disk sectors
-    ** containing the master journal filename is corrupted. This means
-    ** definitely roll back, so just return SQLITE_OK and report a (nul)
-    ** master-journal filename.
-    */
-    zMaster[0] = '\0';
+  assert( id!=0 );
+  OSTRACE2("CLOSE %d\n", pFile->h);
+  do{
+    rc = CloseHandle(pFile->h);
+  }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
+#if SQLITE_OS_WINCE
+#define WINCE_DELETION_ATTEMPTS 3
+  winceDestroyLock(pFile);
+  if( pFile->zDeleteOnClose ){
+    int cnt = 0;
+    while(
+           DeleteFileW(pFile->zDeleteOnClose)==0
+        && GetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff 
+        && cnt++ < WINCE_DELETION_ATTEMPTS
+    ){
+       Sleep(100);  /* Wait a little before trying again */
+    }
+    free(pFile->zDeleteOnClose);
   }
-   
-  return SQLITE_OK;
+#endif
+  OpenCounter(-1);
+  return rc ? SQLITE_OK : SQLITE_IOERR;
 }
 
 /*
-** Seek the journal file descriptor to the next sector boundary where a
-** journal header may be read or written. Pager.journalOff is updated with
-** the new seek offset.
-**
-** i.e for a sector size of 512:
-**
-** Input Offset              Output Offset
-** ---------------------------------------
-** 0                         0
-** 512                       512
-** 100                       512
-** 2000                      2048
-** 
+** Some microsoft compilers lack this definition.
 */
-static void seekJournalHdr(Pager *pPager){
-  i64 offset = 0;
-  i64 c = pPager->journalOff;
-  if( c ){
-    offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
-  }
-  assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
-  assert( offset>=c );
-  assert( (offset-c)<JOURNAL_HDR_SZ(pPager) );
-  pPager->journalOff = offset;
-}
+#ifndef INVALID_SET_FILE_POINTER
+# define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
 
 /*
-** Write zeros over the header of the journal file.  This has the
-** effect of invalidating the journal file and committing the
-** transaction.
+** Read data from a file into a buffer.  Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
 */
-static int zeroJournalHdr(Pager *pPager, int doTruncate){
-  int rc = SQLITE_OK;
-  static const char zeroHdr[28];
+static int winRead(
+  sqlite3_file *id,          /* File to read from */
+  void *pBuf,                /* Write content into this buffer */
+  int amt,                   /* Number of bytes to read */
+  sqlite3_int64 offset       /* Begin reading at this offset */
+){
+  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
+  LONG lowerBits = (LONG)(offset & 0xffffffff);
+  DWORD rc;
+  winFile *pFile = (winFile*)id;
+  DWORD error;
+  DWORD got;
 
-  if( pPager->journalOff ){
-    IOTRACE(("JZEROHDR %p\n", pPager))
-    if( doTruncate ){
-      rc = sqlite3OsTruncate(pPager->jfd, 0);
-    }else{
-      rc = sqlite3OsWrite(pPager->jfd, zeroHdr, sizeof(zeroHdr), 0);
-    }
-    if( rc==SQLITE_OK ){
-      rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_DATAONLY|pPager->sync_flags);
-    }
+  assert( id!=0 );
+  SimulateIOError(return SQLITE_IOERR_READ);
+  OSTRACE3("READ %d lock=%d\n", pFile->h, pFile->locktype);
+  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
+    pFile->lastErrno = error;
+    return SQLITE_FULL;
+  }
+  if( !ReadFile(pFile->h, pBuf, amt, &got, 0) ){
+    pFile->lastErrno = GetLastError();
+    return SQLITE_IOERR_READ;
+  }
+  if( got==(DWORD)amt ){
+    return SQLITE_OK;
+  }else{
+    /* Unread parts of the buffer must be zero-filled */
+    memset(&((char*)pBuf)[got], 0, amt-got);
+    return SQLITE_IOERR_SHORT_READ;
   }
-  return rc;
 }
 
 /*
-** The journal file must be open when this routine is called. A journal
-** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
-** current location.
-**
-** The format for the journal header is as follows:
-** - 8 bytes: Magic identifying journal format.
-** - 4 bytes: Number of records in journal, or -1 no-sync mode is on.
-** - 4 bytes: Random number used for page hash.
-** - 4 bytes: Initial database page count.
-** - 4 bytes: Sector size used by the process that wrote this journal.
-** - 4 bytes: Database page size.
-** 
-** Followed by (JOURNAL_HDR_SZ - 28) bytes of unused space.
+** Write data from a buffer into a file.  Return SQLITE_OK on success
+** or some other error code on failure.
 */
-static int writeJournalHdr(Pager *pPager){
-  int rc = SQLITE_OK;
-  char *zHeader = pPager->pTmpSpace;
-  int nHeader = pPager->pageSize;
-  int nWrite;
-
-  if( nHeader>JOURNAL_HDR_SZ(pPager) ){
-    nHeader = JOURNAL_HDR_SZ(pPager);
-  }
+static int winWrite(
+  sqlite3_file *id,         /* File to write into */
+  const void *pBuf,         /* The bytes to be written */
+  int amt,                  /* Number of bytes to write */
+  sqlite3_int64 offset      /* Offset into the file to begin writing at */
+){
+  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
+  LONG lowerBits = (LONG)(offset & 0xffffffff);
+  DWORD rc;
+  winFile *pFile = (winFile*)id;
+  DWORD error;
+  DWORD wrote = 0;
 
-  if( pPager->stmtHdrOff==0 ){
-    pPager->stmtHdrOff = pPager->journalOff;
+  assert( id!=0 );
+  SimulateIOError(return SQLITE_IOERR_WRITE);
+  SimulateDiskfullError(return SQLITE_FULL);
+  OSTRACE3("WRITE %d lock=%d\n", pFile->h, pFile->locktype);
+  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
+    pFile->lastErrno = error;
+    return SQLITE_FULL;
   }
-
-  seekJournalHdr(pPager);
-  pPager->journalHdr = pPager->journalOff;
-
-  memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
-
-  /* 
-  ** Write the nRec Field - the number of page records that follow this
-  ** journal header. Normally, zero is written to this value at this time.
-  ** After the records are added to the journal (and the journal synced, 
-  ** if in full-sync mode), the zero is overwritten with the true number
-  ** of records (see syncJournal()).
-  **
-  ** A faster alternative is to write 0xFFFFFFFF to the nRec field. When
-  ** reading the journal this value tells SQLite to assume that the
-  ** rest of the journal file contains valid page records. This assumption
-  ** is dangerous, as if a failure occured whilst writing to the journal
-  ** file it may contain some garbage data. There are two scenarios
-  ** where this risk can be ignored:
-  **
-  **   * When the pager is in no-sync mode. Corruption can follow a
-  **     power failure in this case anyway.
-  **
-  **   * When the SQLITE_IOCAP_SAFE_APPEND flag is set. This guarantees
-  **     that garbage data is never appended to the journal file.
-  */
-  assert(pPager->fd->pMethods||pPager->noSync);
-  if( (pPager->noSync) 
-   || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
+  assert( amt>0 );
+  while(
+     amt>0
+     && (rc = WriteFile(pFile->h, pBuf, amt, &wrote, 0))!=0
+     && wrote>0
   ){
-    put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
-  }else{
-    put32bits(&zHeader[sizeof(aJournalMagic)], 0);
-  }
-
-  /* The random check-hash initialiser */ 
-  sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
-  put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
-  /* The initial database size */
-  put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbSize);
-  /* The assumed sector size for this process */
-  put32bits(&zHeader[sizeof(aJournalMagic)+12], pPager->sectorSize);
-  if( pPager->journalHdr==0 ){
-    /* The page size */
-    put32bits(&zHeader[sizeof(aJournalMagic)+16], pPager->pageSize);
+    amt -= wrote;
+    pBuf = &((char*)pBuf)[wrote];
   }
-
-  for(nWrite=0; rc==SQLITE_OK&&nWrite<JOURNAL_HDR_SZ(pPager); nWrite+=nHeader){
-    IOTRACE(("JHDR %p %lld %d\n", pPager, pPager->journalHdr, nHeader))
-    rc = sqlite3OsWrite(pPager->jfd, zHeader, nHeader, pPager->journalOff);
-    pPager->journalOff += nHeader;
+  if( !rc || amt>(int)wrote ){
+    pFile->lastErrno = GetLastError();
+    return SQLITE_FULL;
   }
-
-  return rc;
+  return SQLITE_OK;
 }
 
 /*
-** The journal file must be open when this is called. A journal header file
-** (JOURNAL_HDR_SZ bytes) is read from the current location in the journal
-** file. See comments above function writeJournalHdr() for a description of
-** the journal header format.
-**
-** If the header is read successfully, *nRec is set to the number of
-** page records following this header and *dbSize is set to the size of the
-** database before the transaction began, in pages. Also, pPager->cksumInit
-** is set to the value read from the journal header. SQLITE_OK is returned
-** in this case.
-**
-** If the journal header file appears to be corrupted, SQLITE_DONE is
-** returned and *nRec and *dbSize are not set.  If JOURNAL_HDR_SZ bytes
-** cannot be read from the journal file an error code is returned.
+** Truncate an open file to a specified size
 */
-static int readJournalHdr(
-  Pager *pPager, 
-  i64 journalSize,
-  u32 *pNRec, 
-  u32 *pDbSize
-){
-  int rc;
-  unsigned char aMagic[8]; /* A buffer to hold the magic header */
-  i64 jrnlOff;
-  int iPageSize;
-
-  seekJournalHdr(pPager);
-  if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
-    return SQLITE_DONE;
-  }
-  jrnlOff = pPager->journalOff;
-
-  rc = sqlite3OsRead(pPager->jfd, aMagic, sizeof(aMagic), jrnlOff);
-  if( rc ) return rc;
-  jrnlOff += sizeof(aMagic);
+static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
+  LONG upperBits = (LONG)((nByte>>32) & 0x7fffffff);
+  LONG lowerBits = (LONG)(nByte & 0xffffffff);
+  DWORD rc;
+  winFile *pFile = (winFile*)id;
+  DWORD error;
 
-  if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
-    return SQLITE_DONE;
+  assert( id!=0 );
+  OSTRACE3("TRUNCATE %d %lld\n", pFile->h, nByte);
+  SimulateIOError(return SQLITE_IOERR_TRUNCATE);
+  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
+    pFile->lastErrno = error;
+    return SQLITE_IOERR_TRUNCATE;
   }
-
-  rc = read32bits(pPager->jfd, jrnlOff, pNRec);
-  if( rc ) return rc;
-
-  rc = read32bits(pPager->jfd, jrnlOff+4, &pPager->cksumInit);
-  if( rc ) return rc;
-
-  rc = read32bits(pPager->jfd, jrnlOff+8, pDbSize);
-  if( rc ) return rc;
-
-  rc = read32bits(pPager->jfd, jrnlOff+16, (u32 *)&iPageSize);
-  if( rc==SQLITE_OK 
-   && iPageSize>=512 
-   && iPageSize<=SQLITE_MAX_PAGE_SIZE 
-   && ((iPageSize-1)&iPageSize)==0 
-  ){
-    u16 pagesize = iPageSize;
-    rc = sqlite3PagerSetPagesize(pPager, &pagesize);
+  /* SetEndOfFile will fail if nByte is negative */
+  if( !SetEndOfFile(pFile->h) ){
+    pFile->lastErrno = GetLastError();
+    return SQLITE_IOERR_TRUNCATE;
   }
-  if( rc ) return rc;
-
-  /* Update the assumed sector-size to match the value used by 
-  ** the process that created this journal. If this journal was
-  ** created by a process other than this one, then this routine
-  ** is being called from within pager_playback(). The local value
-  ** of Pager.sectorSize is restored at the end of that routine.
-  */
-  rc = read32bits(pPager->jfd, jrnlOff+12, (u32 *)&pPager->sectorSize);
-  if( rc ) return rc;
-
-  pPager->journalOff += JOURNAL_HDR_SZ(pPager);
   return SQLITE_OK;
 }
 
+#ifdef SQLITE_TEST
+/*
+** Count the number of fullsyncs and normal syncs.  This is used to test
+** that syncs and fullsyncs are occuring at the right times.
+*/
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
 
 /*
-** Write the supplied master journal name into the journal file for pager
-** pPager at the current location. The master journal name must be the last
-** thing written to a journal file. If the pager is in full-sync mode, the
-** journal file descriptor is advanced to the next sector boundary before
-** anything is written. The format is:
-**
-** + 4 bytes: PAGER_MJ_PGNO.
-** + N bytes: length of master journal name.
-** + 4 bytes: N
-** + 4 bytes: Master journal name checksum.
-** + 8 bytes: aJournalMagic[].
-**
-** The master journal page checksum is the sum of the bytes in the master
-** journal name.
-**
-** If zMaster is a NULL pointer (occurs for a single database transaction), 
-** this call is a no-op.
+** Make sure all writes to a particular file are committed to disk.
 */
-static int writeMasterJournal(Pager *pPager, const char *zMaster){
-  int rc;
-  int len; 
-  int i; 
-  i64 jrnlOff;
-  i64 jrnlSize;
-  u32 cksum = 0;
-  char zBuf[sizeof(aJournalMagic)+2*4];
-
-  if( !zMaster || pPager->setMaster) return SQLITE_OK;
-  pPager->setMaster = 1;
+static int winSync(sqlite3_file *id, int flags){
+#ifndef SQLITE_NO_SYNC
+  winFile *pFile = (winFile*)id;
 
-  len = strlen(zMaster);
-  for(i=0; i<len; i++){
-    cksum += zMaster[i];
+  assert( id!=0 );
+  OSTRACE3("SYNC %d lock=%d\n", pFile->h, pFile->locktype);
+#else
+  UNUSED_PARAMETER(id);
+#endif
+#ifndef SQLITE_TEST
+  UNUSED_PARAMETER(flags);
+#else
+  if( flags & SQLITE_SYNC_FULL ){
+    sqlite3_fullsync_count++;
   }
-
-  /* If in full-sync mode, advance to the next disk sector before writing
-  ** the master journal name. This is in case the previous page written to
-  ** the journal has already been synced.
+  sqlite3_sync_count++;
+#endif
+  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+  ** no-op
   */
-  if( pPager->fullSync ){
-    seekJournalHdr(pPager);
-  }
-  jrnlOff = pPager->journalOff;
-  pPager->journalOff += (len+20);
-
-  rc = write32bits(pPager->jfd, jrnlOff, PAGER_MJ_PGNO(pPager));
-  if( rc!=SQLITE_OK ) return rc;
-  jrnlOff += 4;
-
-  rc = sqlite3OsWrite(pPager->jfd, zMaster, len, jrnlOff);
-  if( rc!=SQLITE_OK ) return rc;
-  jrnlOff += len;
-
-  put32bits(zBuf, len);
-  put32bits(&zBuf[4], cksum);
-  memcpy(&zBuf[8], aJournalMagic, sizeof(aJournalMagic));
-  rc = sqlite3OsWrite(pPager->jfd, zBuf, 8+sizeof(aJournalMagic), jrnlOff);
-  jrnlOff += 8+sizeof(aJournalMagic);
-  pPager->needSync = !pPager->noSync;
-
-  /* If the pager is in peristent-journal mode, then the physical 
-  ** journal-file may extend past the end of the master-journal name
-  ** and 8 bytes of magic data just written to the file. This is 
-  ** dangerous because the code to rollback a hot-journal file
-  ** will not be able to find the master-journal name to determine 
-  ** whether or not the journal is hot. 
-  **
-  ** Easiest thing to do in this scenario is to truncate the journal 
-  ** file to the required size.
-  */ 
-  if( (rc==SQLITE_OK)
-   && (rc = sqlite3OsFileSize(pPager->jfd, &jrnlSize))==SQLITE_OK
-   && jrnlSize>jrnlOff
-  ){
-    rc = sqlite3OsTruncate(pPager->jfd, jrnlOff);
+#ifdef SQLITE_NO_SYNC
+    return SQLITE_OK;
+#else
+  if( FlushFileBuffers(pFile->h) ){
+    return SQLITE_OK;
+  }else{
+    pFile->lastErrno = GetLastError();
+    return SQLITE_IOERR;
   }
-  return rc;
+#endif
 }
 
 /*
-** Add or remove a page from the list of all pages that are in the
-** statement journal.
-**
-** The Pager keeps a separate list of pages that are currently in
-** the statement journal.  This helps the sqlite3PagerStmtCommit()
-** routine run MUCH faster for the common case where there are many
-** pages in memory but only a few are in the statement journal.
+** Determine the current size of a file in bytes
 */
-static void page_add_to_stmt_list(PgHdr *pPg){
-  Pager *pPager = pPg->pPager;
-  PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-  assert( MEMDB );
-  if( !pHist->inStmt ){
-    assert( pHist->pPrevStmt==0 && pHist->pNextStmt==0 );
-    if( pPager->pStmt ){
-      PGHDR_TO_HIST(pPager->pStmt, pPager)->pPrevStmt = pPg;
-    }
-    pHist->pNextStmt = pPager->pStmt;
-    pPager->pStmt = pPg;
-    pHist->inStmt = 1;
+static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
+  DWORD upperBits;
+  DWORD lowerBits;
+  winFile *pFile = (winFile*)id;
+  DWORD error;
+
+  assert( id!=0 );
+  SimulateIOError(return SQLITE_IOERR_FSTAT);
+  lowerBits = GetFileSize(pFile->h, &upperBits);
+  if(   (lowerBits == INVALID_FILE_SIZE)
+     && ((error = GetLastError()) != NO_ERROR) )
+  {
+    pFile->lastErrno = error;
+    return SQLITE_IOERR_FSTAT;
   }
+  *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
+  return SQLITE_OK;
 }
 
 /*
-** Find a page in the hash table given its page number.  Return
-** a pointer to the page or NULL if not found.
+** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
 */
-static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
-  PgHdr *p;
-  if( pPager->aHash==0 ) return 0;
-  p = pPager->aHash[pgno & (pPager->nHash-1)];
-  while( p && p->pgno!=pgno ){
-    p = p->pNextHash;
-  }
-  return p;
-}
+#ifndef LOCKFILE_FAIL_IMMEDIATELY
+# define LOCKFILE_FAIL_IMMEDIATELY 1
+#endif
 
 /*
-** Clear the in-memory cache.  This routine
-** sets the state of the pager back to what it was when it was first
-** opened.  Any outstanding pages are invalidated and subsequent attempts
-** to access those pages will likely result in a coredump.
+** Acquire a reader lock.
+** Different API routines are called depending on whether or not this
+** is Win95 or WinNT.
 */
-static void pager_reset(Pager *pPager){
-  PgHdr *pPg, *pNext;
-  if( pPager->errCode ) return;
-  for(pPg=pPager->pAll; pPg; pPg=pNext){
-    IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
-    PAGER_INCR(sqlite3_pager_pgfree_count);
-    pNext = pPg->pNextAll;
-    lruListRemove(pPg);
-    sqlite3_free(pPg->pData);
-    sqlite3_free(pPg);
-  }
-  assert(pPager->lru.pFirst==0);
-  assert(pPager->lru.pFirstSynced==0);
-  assert(pPager->lru.pLast==0);
-  pPager->pStmt = 0;
-  pPager->pAll = 0;
-  pPager->pDirty = 0;
-  pPager->nHash = 0;
-  sqlite3_free(pPager->aHash);
-  pPager->nPage = 0;
-  pPager->aHash = 0;
-  pPager->nRef = 0;
-}
-
-/*
-** Unlock the database file. 
-**
-** If the pager is currently in error state, discard the contents of 
-** the cache and reset the Pager structure internal state. If there is
-** an open journal-file, then the next time a shared-lock is obtained
-** on the pager file (by this or any other process), it will be
-** treated as a hot-journal and rolled back.
+static int getReadLock(winFile *pFile){
+  int res;
+  if( isNT() ){
+    OVERLAPPED ovlp;
+    ovlp.Offset = SHARED_FIRST;
+    ovlp.OffsetHigh = 0;
+    ovlp.hEvent = 0;
+    res = LockFileEx(pFile->h, LOCKFILE_FAIL_IMMEDIATELY,
+                     0, SHARED_SIZE, 0, &ovlp);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
 */
-static void pager_unlock(Pager *pPager){
-  if( !pPager->exclusiveMode ){
-    if( !MEMDB ){
-      int rc = osUnlock(pPager->fd, NO_LOCK);
-      if( rc ) pPager->errCode = rc;
-      pPager->dbSize = -1;
-      IOTRACE(("UNLOCK %p\n", pPager))
-
-      /* Always close the journal file when dropping the database lock.
-      ** Otherwise, another connection with journal_mode=delete might
-      ** delete the file out from under us.
-      */
-      if( pPager->journalOpen ){
-        sqlite3OsClose(pPager->jfd);
-        pPager->journalOpen = 0;
-        sqlite3BitvecDestroy(pPager->pInJournal);
-        pPager->pInJournal = 0;
-      }
-
-      /* If Pager.errCode is set, the contents of the pager cache cannot be
-      ** trusted. Now that the pager file is unlocked, the contents of the
-      ** cache can be discarded and the error code safely cleared.
-      */
-      if( pPager->errCode ){
-        if( rc==SQLITE_OK ) pPager->errCode = SQLITE_OK;
-        pager_reset(pPager);
-        if( pPager->stmtOpen ){
-          sqlite3OsClose(pPager->stfd);
-          sqlite3BitvecDestroy(pPager->pInStmt);
-          pPager->pInStmt = 0;
-        }
-        pPager->stmtOpen = 0;
-        pPager->stmtInUse = 0;
-        pPager->journalOff = 0;
-        pPager->journalStarted = 0;
-        pPager->stmtAutoopen = 0;
-        pPager->origDbSize = 0;
-      }
-    }
-
-    if( !MEMDB || pPager->errCode==SQLITE_OK ){
-      pPager->state = PAGER_UNLOCK;
-      pPager->changeCountDone = 0;
-    }
+#if SQLITE_OS_WINCE==0
+  }else{
+    int lk;
+    sqlite3_randomness(sizeof(lk), &lk);
+    pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
+    res = LockFile(pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+#endif
   }
-}
-
-/*
-** Execute a rollback if a transaction is active and unlock the 
-** database file. If the pager has already entered the error state, 
-** do not attempt the rollback.
-*/
-static void pagerUnlockAndRollback(Pager *p){
-  /* assert( p->state>=PAGER_RESERVED || p->journalOpen==0 ); */
-  if( p->errCode==SQLITE_OK && p->state>=PAGER_RESERVED ){
-    sqlite3FaultBeginBenign(-1);
-    sqlite3PagerRollback(p);
-    sqlite3FaultEndBenign(-1);
+  if( res == 0 ){
+    pFile->lastErrno = GetLastError();
   }
-  pager_unlock(p);
-#if 0
-  assert( p->errCode || !p->journalOpen || (p->exclusiveMode&&!p->journalOff) );
-  assert( p->errCode || !p->stmtOpen || p->exclusiveMode );
-#endif
+  return res;
 }
 
 /*
-** This routine ends a transaction.  A transaction is ended by either
-** a COMMIT or a ROLLBACK.
-**
-** When this routine is called, the pager has the journal file open and
-** a RESERVED or EXCLUSIVE lock on the database.  This routine will release
-** the database lock and acquires a SHARED lock in its place if that is
-** the appropriate thing to do.  Release locks usually is appropriate,
-** unless we are in exclusive access mode or unless this is a 
-** COMMIT AND BEGIN or ROLLBACK AND BEGIN operation.
-**
-** The journal file is either deleted or truncated.
-**
-** TODO: Consider keeping the journal file open for temporary databases.
-** This might give a performance improvement on windows where opening
-** a file is an expensive operation.
+** Undo a readlock
 */
-static int pager_end_transaction(Pager *pPager, int hasMaster){
-  PgHdr *pPg;
-  int rc = SQLITE_OK;
-  int rc2 = SQLITE_OK;
-  assert( !MEMDB );
-  if( pPager->state<PAGER_RESERVED ){
-    return SQLITE_OK;
-  }
-  sqlite3PagerStmtCommit(pPager);
-  if( pPager->stmtOpen && !pPager->exclusiveMode ){
-    sqlite3OsClose(pPager->stfd);
-    pPager->stmtOpen = 0;
-  }
-  if( pPager->journalOpen ){
-    if( pPager->exclusiveMode 
-     || pPager->journalMode==PAGER_JOURNALMODE_PERSIST
-    ){
-      rc = zeroJournalHdr(pPager, hasMaster);
-      pager_error(pPager, rc);
-      pPager->journalOff = 0;
-      pPager->journalStarted = 0;
-    }else{
-      sqlite3OsClose(pPager->jfd);
-      pPager->journalOpen = 0;
-      if( rc==SQLITE_OK ){
-        rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
-      }
-    }
-    sqlite3BitvecDestroy(pPager->pInJournal);
-    pPager->pInJournal = 0;
-    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-      pPg->inJournal = 0;
-      pPg->dirty = 0;
-      pPg->needSync = 0;
-      pPg->alwaysRollback = 0;
-#ifdef SQLITE_CHECK_PAGES
-      pPg->pageHash = pager_pagehash(pPg);
-#endif
-    }
-    pPager->pDirty = 0;
-    pPager->dirtyCache = 0;
-    pPager->nRec = 0;
+static int unlockReadLock(winFile *pFile){
+  int res;
+  if( isNT() ){
+    res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+*/
+#if SQLITE_OS_WINCE==0
   }else{
-    assert( pPager->pInJournal==0 );
+    res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0);
+#endif
   }
-
-  if( !pPager->exclusiveMode ){
-    rc2 = osUnlock(pPager->fd, SHARED_LOCK);
-    pPager->state = PAGER_SHARED;
-  }else if( pPager->state==PAGER_SYNCED ){
-    pPager->state = PAGER_EXCLUSIVE;
+  if( res == 0 ){
+    pFile->lastErrno = GetLastError();
   }
-  pPager->origDbSize = 0;
-  pPager->setMaster = 0;
-  pPager->needSync = 0;
-  lruListSetFirstSynced(pPager);
-  pPager->dbSize = -1;
-  pPager->dbModified = 0;
-
-  return (rc==SQLITE_OK?rc2:rc);
+  return res;
 }
 
 /*
-** Compute and return a checksum for the page of data.
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
 **
-** This is not a real checksum.  It is really just the sum of the 
-** random initial value and the page number.  We experimented with
-** a checksum of the entire data, but that was found to be too slow.
+**     (1) SHARED_LOCK
+**     (2) RESERVED_LOCK
+**     (3) PENDING_LOCK
+**     (4) EXCLUSIVE_LOCK
 **
-** Note that the page number is stored at the beginning of data and
-** the checksum is stored at the end.  This is important.  If journal
-** corruption occurs due to a power failure, the most likely scenario
-** is that one end or the other of the record will be changed.  It is
-** much less likely that the two ends of the journal record will be
-** correct and the middle be corrupt.  Thus, this "checksum" scheme,
-** though fast and simple, catches the mostly likely kind of corruption.
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between.  The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal.  The following chart shows the allowed
+** transitions and the inserted intermediate states:
 **
-** FIX ME:  Consider adding every 200th (or so) byte of the data to the
-** checksum.  That way if a single page spans 3 or more disk sectors and
-** only the middle sector is corrupt, we will still have a reasonable
-** chance of failing the checksum and thus detecting the problem.
-*/
-static u32 pager_cksum(Pager *pPager, const u8 *aData){
-  u32 cksum = pPager->cksumInit;
-  int i = pPager->pageSize-200;
-  while( i>0 ){
-    cksum += aData[i];
-    i -= 200;
-  }
-  return cksum;
-}
-
-/* Forward declaration */
-static void makeClean(PgHdr*);
-
-/*
-** Read a single page from the journal file opened on file descriptor
-** jfd.  Playback this one page.
+**    UNLOCKED -> SHARED
+**    SHARED -> RESERVED
+**    SHARED -> (PENDING) -> EXCLUSIVE
+**    RESERVED -> (PENDING) -> EXCLUSIVE
+**    PENDING -> EXCLUSIVE
 **
-** If useCksum==0 it means this journal does not use checksums.  Checksums
-** are not used in statement journals because statement journals do not
-** need to survive power failures.
+** This routine will only increase a lock.  The winUnlock() routine
+** erases all locks at once and returns us immediately to locking level 0.
+** It is not possible to lower the locking level one step at a time.  You
+** must go straight to locking level 0.
 */
-static int pager_playback_one_page(
-  Pager *pPager, 
-  sqlite3_file *jfd,
-  i64 offset,
-  int useCksum
-){
-  int rc;
-  PgHdr *pPg;                   /* An existing page in the cache */
-  Pgno pgno;                    /* The page number of a page in journal */
-  u32 cksum;                    /* Checksum used for sanity checking */
-  u8 *aData = (u8 *)pPager->pTmpSpace;   /* Temp storage for a page */
+static int winLock(sqlite3_file *id, int locktype){
+  int rc = SQLITE_OK;    /* Return code from subroutines */
+  int res = 1;           /* Result of a windows lock call */
+  int newLocktype;       /* Set pFile->locktype to this value before exiting */
+  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
+  winFile *pFile = (winFile*)id;
+  DWORD error = NO_ERROR;
+
+  assert( id!=0 );
+  OSTRACE5("LOCK %d %d was %d(%d)\n",
+          pFile->h, locktype, pFile->locktype, pFile->sharedLockByte);
 
-  /* useCksum should be true for the main journal and false for
-  ** statement journals.  Verify that this is always the case
+  /* If there is already a lock of this type or more restrictive on the
+  ** OsFile, do nothing. Don't use the end_lock: exit path, as
+  ** sqlite3OsEnterMutex() hasn't been called yet.
   */
-  assert( jfd == (useCksum ? pPager->jfd : pPager->stfd) );
-  assert( aData );
+  if( pFile->locktype>=locktype ){
+    return SQLITE_OK;
+  }
 
-  rc = read32bits(jfd, offset, &pgno);
-  if( rc!=SQLITE_OK ) return rc;
-  rc = sqlite3OsRead(jfd, aData, pPager->pageSize, offset+4);
-  if( rc!=SQLITE_OK ) return rc;
-  pPager->journalOff += pPager->pageSize + 4;
+  /* Make sure the locking sequence is correct
+  */
+  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
+  assert( locktype!=PENDING_LOCK );
+  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
 
-  /* Sanity checking on the page.  This is more important that I originally
-  ** thought.  If a power failure occurs while the journal is being written,
-  ** it could cause invalid data to be written into the journal.  We need to
-  ** detect this invalid data (with high probability) and ignore it.
+  /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
+  ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
+  ** the PENDING_LOCK byte is temporary.
   */
-  if( pgno==0 || pgno==PAGER_MJ_PGNO(pPager) ){
-    return SQLITE_DONE;
+  newLocktype = pFile->locktype;
+  if(   (pFile->locktype==NO_LOCK)
+     || (   (locktype==EXCLUSIVE_LOCK)
+         && (pFile->locktype==RESERVED_LOCK))
+  ){
+    int cnt = 3;
+    while( cnt-->0 && (res = LockFile(pFile->h, PENDING_BYTE, 0, 1, 0))==0 ){
+      /* Try 3 times to get the pending lock.  The pending lock might be
+      ** held by another reader process who will release it momentarily.
+      */
+      OSTRACE2("could not get a PENDING lock. cnt=%d\n", cnt);
+      Sleep(1);
+    }
+    gotPendingLock = res;
+    if( !res ){
+      error = GetLastError();
+    }
   }
-  if( pgno>(unsigned)pPager->dbSize ){
-    return SQLITE_OK;
+
+  /* Acquire a shared lock
+  */
+  if( locktype==SHARED_LOCK && res ){
+    assert( pFile->locktype==NO_LOCK );
+    res = getReadLock(pFile);
+    if( res ){
+      newLocktype = SHARED_LOCK;
+    }else{
+      error = GetLastError();
+    }
   }
-  if( useCksum ){
-    rc = read32bits(jfd, offset+pPager->pageSize+4, &cksum);
-    if( rc ) return rc;
-    pPager->journalOff += 4;
-    if( pager_cksum(pPager, aData)!=cksum ){
-      return SQLITE_DONE;
+
+  /* Acquire a RESERVED lock
+  */
+  if( locktype==RESERVED_LOCK && res ){
+    assert( pFile->locktype==SHARED_LOCK );
+    res = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
+    if( res ){
+      newLocktype = RESERVED_LOCK;
+    }else{
+      error = GetLastError();
     }
   }
 
-  assert( pPager->state==PAGER_RESERVED || pPager->state>=PAGER_EXCLUSIVE );
+  /* Acquire a PENDING lock
+  */
+  if( locktype==EXCLUSIVE_LOCK && res ){
+    newLocktype = PENDING_LOCK;
+    gotPendingLock = 0;
+  }
 
-  /* If the pager is in RESERVED state, then there must be a copy of this
-  ** page in the pager cache. In this case just update the pager cache,
-  ** not the database file. The page is left marked dirty in this case.
-  **
-  ** An exception to the above rule: If the database is in no-sync mode
-  ** and a page is moved during an incremental vacuum then the page may
-  ** not be in the pager cache. Later: if a malloc() or IO error occurs
-  ** during a Movepage() call, then the page may not be in the cache
-  ** either. So the condition described in the above paragraph is not
-  ** assert()able.
-  **
-  ** If in EXCLUSIVE state, then we update the pager cache if it exists
-  ** and the main file. The page is then marked not dirty.
-  **
-  ** Ticket #1171:  The statement journal might contain page content that is
-  ** different from the page content at the start of the transaction.
-  ** This occurs when a page is changed prior to the start of a statement
-  ** then changed again within the statement.  When rolling back such a
-  ** statement we must not write to the original database unless we know
-  ** for certain that original page contents are synced into the main rollback
-  ** journal.  Otherwise, a power loss might leave modified data in the
-  ** database file without an entry in the rollback journal that can
-  ** restore the database to its original form.  Two conditions must be
-  ** met before writing to the database files. (1) the database must be
-  ** locked.  (2) we know that the original page content is fully synced
-  ** in the main journal either because the page is not in cache or else
-  ** the page is marked as needSync==0.
-  **
-  ** 2008-04-14:  When attempting to vacuum a corrupt database file, it
-  ** is possible to fail a statement on a database that does not yet exist.
-  ** Do not attempt to write if database file has never been opened.
+  /* Acquire an EXCLUSIVE lock
   */
-  pPg = pager_lookup(pPager, pgno);
-  PAGERTRACE4("PLAYBACK %d page %d hash(%08x)\n",
-               PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, aData));
-  if( pPager->state>=PAGER_EXCLUSIVE && (pPg==0 || pPg->needSync==0)
-        && pPager->fd->pMethods ){
-    i64 offset = (pgno-1)*(i64)pPager->pageSize;
-    rc = sqlite3OsWrite(pPager->fd, aData, pPager->pageSize, offset);
-    if( pPg ){
-      makeClean(pPg);
+  if( locktype==EXCLUSIVE_LOCK && res ){
+    assert( pFile->locktype>=SHARED_LOCK );
+    res = unlockReadLock(pFile);
+    OSTRACE2("unreadlock = %d\n", res);
+    res = LockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+    if( res ){
+      newLocktype = EXCLUSIVE_LOCK;
+    }else{
+      error = GetLastError();
+      OSTRACE2("error-code = %d\n", error);
+      getReadLock(pFile);
     }
   }
-  if( pPg ){
-    /* No page should ever be explicitly rolled back that is in use, except
-    ** for page 1 which is held in use in order to keep the lock on the
-    ** database active. However such a page may be rolled back as a result
-    ** of an internal error resulting in an automatic call to
-    ** sqlite3PagerRollback().
-    */
-    void *pData;
-    /* assert( pPg->nRef==0 || pPg->pgno==1 ); */
-    pData = PGHDR_TO_DATA(pPg);
-    memcpy(pData, aData, pPager->pageSize);
-    if( pPager->xReiniter ){
-      pPager->xReiniter(pPg, pPager->pageSize);
-    }
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
-    /* If this was page 1, then restore the value of Pager.dbFileVers.
-    ** Do this before any decoding. */
-    if( pgno==1 ){
-      memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));
-    }
 
-    /* Decode the page just read from disk */
-    CODEC1(pPager, pData, pPg->pgno, 3);
+  /* If we are holding a PENDING lock that ought to be released, then
+  ** release it now.
+  */
+  if( gotPendingLock && locktype==SHARED_LOCK ){
+    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
+  }
+
+  /* Update the state of the lock has held in the file descriptor then
+  ** return the appropriate result code.
+  */
+  if( res ){
+    rc = SQLITE_OK;
+  }else{
+    OSTRACE4("LOCK FAILED %d trying for %d but got %d\n", pFile->h,
+           locktype, newLocktype);
+    pFile->lastErrno = error;
+    rc = SQLITE_BUSY;
   }
+  pFile->locktype = (u8)newLocktype;
   return rc;
 }
 
 /*
-** Parameter zMaster is the name of a master journal file. A single journal
-** file that referred to the master journal file has just been rolled back.
-** This routine checks if it is possible to delete the master journal file,
-** and does so if it is.
-**
-** Argument zMaster may point to Pager.pTmpSpace. So that buffer is not 
-** available for use within this function.
-**
-**
-** The master journal file contains the names of all child journals.
-** To tell if a master journal can be deleted, check to each of the
-** children.  If all children are either missing or do not refer to
-** a different master journal, then this master journal can be deleted.
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, return
+** non-zero, otherwise zero.
 */
-static int pager_delmaster(Pager *pPager, const char *zMaster){
-  sqlite3_vfs *pVfs = pPager->pVfs;
+static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
   int rc;
-  int master_open = 0;
-  sqlite3_file *pMaster;
-  sqlite3_file *pJournal;
-  char *zMasterJournal = 0; /* Contents of master journal file */
-  i64 nMasterJournal;       /* Size of master journal file */
+  winFile *pFile = (winFile*)id;
 
-  /* Open the master journal file exclusively in case some other process
-  ** is running this routine also. Not that it makes too much difference.
-  */
-  pMaster = (sqlite3_file *)sqlite3_malloc(pVfs->szOsFile * 2);
-  pJournal = (sqlite3_file *)(((u8 *)pMaster) + pVfs->szOsFile);
-  if( !pMaster ){
-    rc = SQLITE_NOMEM;
+  assert( id!=0 );
+  if( pFile->locktype>=RESERVED_LOCK ){
+    rc = 1;
+    OSTRACE3("TEST WR-LOCK %d %d (local)\n", pFile->h, rc);
   }else{
-    int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MASTER_JOURNAL);
-    rc = sqlite3OsOpen(pVfs, zMaster, pMaster, flags, 0);
-  }
-  if( rc!=SQLITE_OK ) goto delmaster_out;
-  master_open = 1;
-
-  rc = sqlite3OsFileSize(pMaster, &nMasterJournal);
-  if( rc!=SQLITE_OK ) goto delmaster_out;
-
-  if( nMasterJournal>0 ){
-    char *zJournal;
-    char *zMasterPtr = 0;
-    int nMasterPtr = pPager->pVfs->mxPathname+1;
-
-    /* Load the entire master journal file into space obtained from
-    ** sqlite3_malloc() and pointed to by zMasterJournal. 
-    */
-    zMasterJournal = (char *)sqlite3_malloc(nMasterJournal + nMasterPtr);
-    if( !zMasterJournal ){
-      rc = SQLITE_NOMEM;
-      goto delmaster_out;
-    }
-    zMasterPtr = &zMasterJournal[nMasterJournal];
-    rc = sqlite3OsRead(pMaster, zMasterJournal, nMasterJournal, 0);
-    if( rc!=SQLITE_OK ) goto delmaster_out;
-
-    zJournal = zMasterJournal;
-    while( (zJournal-zMasterJournal)<nMasterJournal ){
-      rc = sqlite3OsAccess(pVfs, zJournal, SQLITE_ACCESS_EXISTS);
-      if( rc!=0 && rc!=1 ){
-        rc = SQLITE_IOERR_NOMEM;
-        goto delmaster_out;
-      }
-      if( rc==1 ){
-        /* One of the journals pointed to by the master journal exists.
-        ** Open it and check if it points at the master journal. If
-        ** so, return without deleting the master journal file.
-        */
-        int c;
-        int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL);
-        rc = sqlite3OsOpen(pVfs, zJournal, pJournal, flags, 0);
-        if( rc!=SQLITE_OK ){
-          goto delmaster_out;
-        }
-
-        rc = readMasterJournal(pJournal, zMasterPtr, nMasterPtr);
-        sqlite3OsClose(pJournal);
-        if( rc!=SQLITE_OK ){
-          goto delmaster_out;
-        }
-
-        c = zMasterPtr[0]!=0 && strcmp(zMasterPtr, zMaster)==0;
-        if( c ){
-          /* We have a match. Do not delete the master journal file. */
-          goto delmaster_out;
-        }
-      }
-      zJournal += (strlen(zJournal)+1);
+    rc = LockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
+    if( rc ){
+      UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
     }
+    rc = !rc;
+    OSTRACE3("TEST WR-LOCK %d %d (remote)\n", pFile->h, rc);
   }
-  
-  rc = sqlite3OsDelete(pVfs, zMaster, 0);
-
-delmaster_out:
-  if( zMasterJournal ){
-    sqlite3_free(zMasterJournal);
-  }  
-  if( master_open ){
-    sqlite3OsClose(pMaster);
-  }
-  sqlite3_free(pMaster);
-  return rc;
+  *pResOut = rc;
+  return SQLITE_OK;
 }
 
-
-static void pager_truncate_cache(Pager *pPager);
-
 /*
-** Truncate the main file of the given pager to the number of pages
-** indicated. Also truncate the cached representation of the file.
+** Lower the locking level on file descriptor id to locktype.  locktype
+** must be either NO_LOCK or SHARED_LOCK.
 **
-** Might might be the case that the file on disk is smaller than nPage.
-** This can happen, for example, if we are in the middle of a transaction
-** which has extended the file size and the new pages are still all held
-** in cache, then an INSERT or UPDATE does a statement rollback.  Some
-** operating system implementations can get confused if you try to
-** truncate a file to some size that is larger than it currently is,
-** so detect this case and write a single zero byte to the end of the new
-** file instead.
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** It is not possible for this routine to fail if the second argument
+** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
+** might return SQLITE_IOERR;
 */
-static int pager_truncate(Pager *pPager, int nPage){
+static int winUnlock(sqlite3_file *id, int locktype){
+  int type;
+  winFile *pFile = (winFile*)id;
   int rc = SQLITE_OK;
-  if( pPager->state>=PAGER_EXCLUSIVE && pPager->fd->pMethods ){
-    i64 currentSize, newSize;
-    rc = sqlite3OsFileSize(pPager->fd, &currentSize);
-    newSize = pPager->pageSize*(i64)nPage;
-    if( rc==SQLITE_OK && currentSize!=newSize ){
-      if( currentSize>newSize ){
-        rc = sqlite3OsTruncate(pPager->fd, newSize);
-      }else{
-        rc = sqlite3OsWrite(pPager->fd, "", 1, newSize-1);
-      }
+  assert( pFile!=0 );
+  assert( locktype<=SHARED_LOCK );
+  OSTRACE5("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype,
+          pFile->locktype, pFile->sharedLockByte);
+  type = pFile->locktype;
+  if( type>=EXCLUSIVE_LOCK ){
+    UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+    if( locktype==SHARED_LOCK && !getReadLock(pFile) ){
+      /* This should never happen.  We should always be able to
+      ** reacquire the read lock */
+      rc = SQLITE_IOERR_UNLOCK;
     }
   }
-  if( rc==SQLITE_OK ){
-    pPager->dbSize = nPage;
-    pager_truncate_cache(pPager);
+  if( type>=RESERVED_LOCK ){
+    UnlockFile(pFile->h, RESERVED_BYTE, 0, 1, 0);
+  }
+  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
+    unlockReadLock(pFile);
+  }
+  if( type>=PENDING_LOCK ){
+    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
   }
+  pFile->locktype = (u8)locktype;
   return rc;
 }
 
 /*
-** Set the sectorSize for the given pager.
-**
-** The sector size is at least as big as the sector size reported
-** by sqlite3OsSectorSize().  The minimum sector size is 512.
+** Control and query of the open file handle.
 */
-static void setSectorSize(Pager *pPager){
-  assert(pPager->fd->pMethods||pPager->tempFile);
-  if( !pPager->tempFile ){
-    /* Sector size doesn't matter for temporary files. Also, the file
-    ** may not have been opened yet, in whcih case the OsSectorSize()
-    ** call will segfault.
-    */
-    pPager->sectorSize = sqlite3OsSectorSize(pPager->fd);
-  }
-  if( pPager->sectorSize<512 ){
-    pPager->sectorSize = 512;
+static int winFileControl(sqlite3_file *id, int op, void *pArg){
+  switch( op ){
+    case SQLITE_FCNTL_LOCKSTATE: {
+      *(int*)pArg = ((winFile*)id)->locktype;
+      return SQLITE_OK;
+    }
+    case SQLITE_LAST_ERRNO: {
+      *(int*)pArg = (int)((winFile*)id)->lastErrno;
+      return SQLITE_OK;
+    }
   }
+  return SQLITE_ERROR;
 }
 
 /*
-** Playback the journal and thus restore the database file to
-** the state it was in before we started making changes.  
-**
-** The journal file format is as follows: 
-**
-**  (1)  8 byte prefix.  A copy of aJournalMagic[].
-**  (2)  4 byte big-endian integer which is the number of valid page records
-**       in the journal.  If this value is 0xffffffff, then compute the
-**       number of page records from the journal size.
-**  (3)  4 byte big-endian integer which is the initial value for the 
-**       sanity checksum.
-**  (4)  4 byte integer which is the number of pages to truncate the
-**       database to during a rollback.
-**  (5)  4 byte big-endian integer which is the sector size.  The header
-**       is this many bytes in size.
-**  (6)  4 byte big-endian integer which is the page case.
-**  (7)  4 byte integer which is the number of bytes in the master journal
-**       name.  The value may be zero (indicate that there is no master
-**       journal.)
-**  (8)  N bytes of the master journal name.  The name will be nul-terminated
-**       and might be shorter than the value read from (5).  If the first byte
-**       of the name is \000 then there is no master journal.  The master
-**       journal name is stored in UTF-8.
-**  (9)  Zero or more pages instances, each as follows:
-**        +  4 byte page number.
-**        +  pPager->pageSize bytes of data.
-**        +  4 byte checksum
-**
-** When we speak of the journal header, we mean the first 8 items above.
-** Each entry in the journal is an instance of the 9th item.
-**
-** Call the value from the second bullet "nRec".  nRec is the number of
-** valid page entries in the journal.  In most cases, you can compute the
-** value of nRec from the size of the journal file.  But if a power
-** failure occurred while the journal was being written, it could be the
-** case that the size of the journal file had already been increased but
-** the extra entries had not yet made it safely to disk.  In such a case,
-** the value of nRec computed from the file size would be too large.  For
-** that reason, we always use the nRec value in the header.
-**
-** If the nRec value is 0xffffffff it means that nRec should be computed
-** from the file size.  This value is used when the user selects the
-** no-sync option for the journal.  A power failure could lead to corruption
-** in this case.  But for things like temporary table (which will be
-** deleted when the power is restored) we don't care.  
-**
-** If the file opened as the journal file is not a well-formed
-** journal file then all pages up to the first corrupted page are rolled
-** back (or no pages if the journal header is corrupted). The journal file
-** is then deleted and SQLITE_OK returned, just as if no corruption had
-** been encountered.
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
 **
-** If an I/O or malloc() error occurs, the journal-file is not deleted
-** and an error code is returned.
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
 */
-static int pager_playback(Pager *pPager, int isHot){
-  sqlite3_vfs *pVfs = pPager->pVfs;
-  i64 szJ;                 /* Size of the journal file in bytes */
-  u32 nRec;                /* Number of Records in the journal */
-  int i;                   /* Loop counter */
-  Pgno mxPg = 0;           /* Size of the original file in pages */
-  int rc;                  /* Result code of a subroutine */
-  int res = 0;             /* Value returned by sqlite3OsAccess() */
-  char *zMaster = 0;       /* Name of master journal file if any */
-
-  /* Figure out how many records are in the journal.  Abort early if
-  ** the journal is empty.
-  */
-  assert( pPager->journalOpen );
-  rc = sqlite3OsFileSize(pPager->jfd, &szJ);
-  if( rc!=SQLITE_OK || szJ==0 ){
-    goto end_playback;
-  }
+static int winSectorSize(sqlite3_file *id){
+  assert( id!=0 );
+  return (int)(((winFile*)id)->sectorSize);
+}
 
-  /* Read the master journal name from the journal, if it is present.
-  ** If a master journal file name is specified, but the file is not
-  ** present on disk, then the journal is not hot and does not need to be
-  ** played back.
-  */
-  zMaster = pPager->pTmpSpace;
-  rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
-  if( rc!=SQLITE_OK || (zMaster[0] 
-   && (res=sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS))==0 ) 
-  ){
-    zMaster = 0;
-    goto end_playback;
-  }
-  zMaster = 0;
-  if( res<0 ){
-    rc = SQLITE_IOERR_NOMEM;
-    goto end_playback;
-  }
-  pPager->journalOff = 0;
+/*
+** Return a vector of device characteristics.
+*/
+static int winDeviceCharacteristics(sqlite3_file *id){
+  UNUSED_PARAMETER(id);
+  return 0;
+}
 
-  /* This loop terminates either when the readJournalHdr() call returns
-  ** SQLITE_DONE or an IO error occurs. */
-  while( 1 ){
+/*
+** This vector defines all the methods that can operate on an
+** sqlite3_file for win32.
+*/
+static const sqlite3_io_methods winIoMethod = {
+  1,                        /* iVersion */
+  winClose,
+  winRead,
+  winWrite,
+  winTruncate,
+  winSync,
+  winFileSize,
+  winLock,
+  winUnlock,
+  winCheckReservedLock,
+  winFileControl,
+  winSectorSize,
+  winDeviceCharacteristics
+};
 
-    /* Read the next journal header from the journal file.  If there are
-    ** not enough bytes left in the journal file for a complete header, or
-    ** it is corrupted, then a process must of failed while writing it.
-    ** This indicates nothing more needs to be rolled back.
-    */
-    rc = readJournalHdr(pPager, szJ, &nRec, &mxPg);
-    if( rc!=SQLITE_OK ){ 
-      if( rc==SQLITE_DONE ){
-        rc = SQLITE_OK;
-      }
-      goto end_playback;
-    }
-
-    /* If nRec is 0xffffffff, then this journal was created by a process
-    ** working in no-sync mode. This means that the rest of the journal
-    ** file consists of pages, there are no more journal headers. Compute
-    ** the value of nRec based on this assumption.
-    */
-    if( nRec==0xffffffff ){
-      assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) );
-      nRec = (szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager);
-    }
+/***************************************************************************
+** Here ends the I/O methods that form the sqlite3_io_methods object.
+**
+** The next block of code implements the VFS methods.
+****************************************************************************/
 
-    /* If nRec is 0 and this rollback is of a transaction created by this
-    ** process and if this is the final header in the journal, then it means
-    ** that this part of the journal was being filled but has not yet been
-    ** synced to disk.  Compute the number of pages based on the remaining
-    ** size of the file.
-    **
-    ** The third term of the test was added to fix ticket #2565.
-    */
-    if( nRec==0 && !isHot &&
-        pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff ){
-      nRec = (szJ - pPager->journalOff) / JOURNAL_PG_SZ(pPager);
-    }
+/*
+** Convert a UTF-8 filename into whatever form the underlying
+** operating system wants filenames in.  Space to hold the result
+** is obtained from malloc and must be freed by the calling
+** function.
+*/
+static void *convertUtf8Filename(const char *zFilename){
+  void *zConverted = 0;
+  if( isNT() ){
+    zConverted = utf8ToUnicode(zFilename);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+*/
+#if SQLITE_OS_WINCE==0
+  }else{
+    zConverted = utf8ToMbcs(zFilename);
+#endif
+  }
+  /* caller will handle out of memory */
+  return zConverted;
+}
 
-    /* If this is the first header read from the journal, truncate the
-    ** database file back to its original size.
-    */
-    if( pPager->journalOff==JOURNAL_HDR_SZ(pPager) ){
-      rc = pager_truncate(pPager, mxPg);
-      if( rc!=SQLITE_OK ){
-        goto end_playback;
-      }
+/*
+** Create a temporary file name in zBuf.  zBuf must be big enough to
+** hold at pVfs->mxPathname characters.
+*/
+static int getTempname(int nBuf, char *zBuf){
+  static char zChars[] =
+    "abcdefghijklmnopqrstuvwxyz"
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "0123456789";
+  size_t i, j;
+  char zTempPath[MAX_PATH+1];
+  if( sqlite3_temp_directory ){
+    sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
+  }else if( isNT() ){
+    char *zMulti;
+    WCHAR zWidePath[MAX_PATH];
+    GetTempPathW(MAX_PATH-30, zWidePath);
+    zMulti = unicodeToUtf8(zWidePath);
+    if( zMulti ){
+      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zMulti);
+      free(zMulti);
+    }else{
+      return SQLITE_NOMEM;
     }
-
-    /* Copy original pages out of the journal and back into the database file.
-    */
-    for(i=0; i<nRec; i++){
-      rc = pager_playback_one_page(pPager, pPager->jfd, pPager->journalOff, 1);
-      if( rc!=SQLITE_OK ){
-        if( rc==SQLITE_DONE ){
-          rc = SQLITE_OK;
-          pPager->journalOff = szJ;
-          break;
-        }else{
-          goto end_playback;
-        }
-      }
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
+*/
+#if SQLITE_OS_WINCE==0
+  }else{
+    char *zUtf8;
+    char zMbcsPath[MAX_PATH];
+    GetTempPathA(MAX_PATH-30, zMbcsPath);
+    zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
+    if( zUtf8 ){
+      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zUtf8);
+      free(zUtf8);
+    }else{
+      return SQLITE_NOMEM;
     }
+#endif
   }
-  /*NOTREACHED*/
-  assert( 0 );
-
-end_playback:
-  if( rc==SQLITE_OK ){
-    zMaster = pPager->pTmpSpace;
-    rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
-  }
-  if( rc==SQLITE_OK ){
-    rc = pager_end_transaction(pPager, zMaster[0]!='\0');
+  for(i=sqlite3Strlen30(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
+  zTempPath[i] = 0;
+  sqlite3_snprintf(nBuf-30, zBuf,
+                   "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
+  j = sqlite3Strlen30(zBuf);
+  sqlite3_randomness(20, &zBuf[j]);
+  for(i=0; i<20; i++, j++){
+    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
   }
-  if( rc==SQLITE_OK && zMaster[0] ){
-    /* If there was a master journal and this routine will return success,
-    ** see if it is possible to delete the master journal.
-    */
-    rc = pager_delmaster(pPager, zMaster);
+  zBuf[j] = 0;
+  OSTRACE2("TEMP FILENAME: %s\n", zBuf);
+  return SQLITE_OK; 
+}
+
+/*
+** The return value of getLastErrorMsg
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated).
+*/
+static int getLastErrorMsg(int nBuf, char *zBuf){
+  DWORD error = GetLastError();
+
+#if SQLITE_OS_WINCE
+  sqlite3_snprintf(nBuf, zBuf, "OsError 0x%x (%u)", error, error);
+#else
+  /* FormatMessage returns 0 on failure.  Otherwise it
+  ** returns the number of TCHARs written to the output
+  ** buffer, excluding the terminating null char.
+  */
+  if (!FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM,
+                      NULL,
+                      error,
+                      0,
+                      zBuf,
+                      nBuf-1,
+                      0))
+  {
+    sqlite3_snprintf(nBuf, zBuf, "OsError 0x%x (%u)", error, error);
   }
+#endif
 
-  /* The Pager.sectorSize variable may have been updated while rolling
-  ** back a journal created by a process with a different sector size
-  ** value. Reset it to the correct value for this process.
-  */
-  setSectorSize(pPager);
-  return rc;
+  return 0;
 }
 
 /*
-** Playback the statement journal.
-**
-** This is similar to playing back the transaction journal but with
-** a few extra twists.
-**
-**    (1)  The number of pages in the database file at the start of
-**         the statement is stored in pPager->stmtSize, not in the
-**         journal file itself.
-**
-**    (2)  In addition to playing back the statement journal, also
-**         playback all pages of the transaction journal beginning
-**         at offset pPager->stmtJSize.
+** Open a file.
 */
-static int pager_stmt_playback(Pager *pPager){
-  i64 szJ;                 /* Size of the full journal */
-  i64 hdrOff;
-  int nRec;                /* Number of Records */
-  int i;                   /* Loop counter */
-  int rc;
+static int winOpen(
+  sqlite3_vfs *pVfs,        /* Not used */
+  const char *zName,        /* Name of the file (UTF-8) */
+  sqlite3_file *id,         /* Write the SQLite file handle here */
+  int flags,                /* Open mode flags */
+  int *pOutFlags            /* Status return flags */
+){
+  HANDLE h;
+  DWORD dwDesiredAccess;
+  DWORD dwShareMode;
+  DWORD dwCreationDisposition;
+  DWORD dwFlagsAndAttributes = 0;
+#if SQLITE_OS_WINCE
+  int isTemp = 0;
+#endif
+  winFile *pFile = (winFile*)id;
+  void *zConverted;                 /* Filename in OS encoding */
+  const char *zUtf8Name = zName;    /* Filename in UTF-8 encoding */
+  char zTmpname[MAX_PATH+1];        /* Buffer used to create temp filename */
 
-  szJ = pPager->journalOff;
+  assert( id!=0 );
+  UNUSED_PARAMETER(pVfs);
 
-  /* Set hdrOff to be the offset just after the end of the last journal
-  ** page written before the first journal-header for this statement
-  ** transaction was written, or the end of the file if no journal
-  ** header was written.
+  /* If the second argument to this function is NULL, generate a 
+  ** temporary file name to use 
   */
-  hdrOff = pPager->stmtHdrOff;
-  assert( pPager->fullSync || !hdrOff );
-  if( !hdrOff ){
-    hdrOff = szJ;
+  if( !zUtf8Name ){
+    int rc = getTempname(MAX_PATH+1, zTmpname);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    zUtf8Name = zTmpname;
   }
-  
-  /* Truncate the database back to its original size.
-  */
-  rc = pager_truncate(pPager, pPager->stmtSize);
-  assert( pPager->state>=PAGER_SHARED );
 
-  /* Figure out how many records are in the statement journal.
-  */
-  assert( pPager->stmtInUse && pPager->journalOpen );
-  nRec = pPager->stmtNRec;
-  
-  /* Copy original pages out of the statement journal and back into the
-  ** database file.  Note that the statement journal omits checksums from
-  ** each record since power-failure recovery is not important to statement
-  ** journals.
-  */
-  for(i=0; i<nRec; i++){
-    i64 offset = i*(4+pPager->pageSize);
-    rc = pager_playback_one_page(pPager, pPager->stfd, offset, 0);
-    assert( rc!=SQLITE_DONE );
-    if( rc!=SQLITE_OK ) goto end_stmt_playback;
+  /* Convert the filename to the system encoding. */
+  zConverted = convertUtf8Filename(zUtf8Name);
+  if( zConverted==0 ){
+    return SQLITE_NOMEM;
   }
 
-  /* Now roll some pages back from the transaction journal. Pager.stmtJSize
-  ** was the size of the journal file when this statement was started, so
-  ** everything after that needs to be rolled back, either into the
-  ** database, the memory cache, or both.
-  **
-  ** If it is not zero, then Pager.stmtHdrOff is the offset to the start
-  ** of the first journal header written during this statement transaction.
-  */
-  pPager->journalOff = pPager->stmtJSize;
-  pPager->cksumInit = pPager->stmtCksum;
-  while( pPager->journalOff < hdrOff ){
-    rc = pager_playback_one_page(pPager, pPager->jfd, pPager->journalOff, 1);
-    assert( rc!=SQLITE_DONE );
-    if( rc!=SQLITE_OK ) goto end_stmt_playback;
+  if( flags & SQLITE_OPEN_READWRITE ){
+    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
+  }else{
+    dwDesiredAccess = GENERIC_READ;
   }
-
-  while( pPager->journalOff < szJ ){
-    u32 nJRec;         /* Number of Journal Records */
-    u32 dummy;
-    rc = readJournalHdr(pPager, szJ, &nJRec, &dummy);
-    if( rc!=SQLITE_OK ){
-      assert( rc!=SQLITE_DONE );
-      goto end_stmt_playback;
-    }
-    if( nJRec==0 ){
-      nJRec = (szJ - pPager->journalOff) / (pPager->pageSize+8);
-    }
-    for(i=nJRec-1; i>=0 && pPager->journalOff < szJ; i--){
-      rc = pager_playback_one_page(pPager, pPager->jfd, pPager->journalOff, 1);
-      assert( rc!=SQLITE_DONE );
-      if( rc!=SQLITE_OK ) goto end_stmt_playback;
-    }
+  /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
+  ** created. SQLite doesn't use it to indicate "exclusive access" 
+  ** as it is usually understood.
+  */
+  assert(!(flags & SQLITE_OPEN_EXCLUSIVE) || (flags & SQLITE_OPEN_CREATE));
+  if( flags & SQLITE_OPEN_EXCLUSIVE ){
+    /* Creates a new file, only if it does not already exist. */
+    /* If the file exists, it fails. */
+    dwCreationDisposition = CREATE_NEW;
+  }else if( flags & SQLITE_OPEN_CREATE ){
+    /* Open existing file, or create if it doesn't exist */
+    dwCreationDisposition = OPEN_ALWAYS;
+  }else{
+    /* Opens a file, only if it exists. */
+    dwCreationDisposition = OPEN_EXISTING;
   }
-
-  pPager->journalOff = szJ;
-  
-end_stmt_playback:
-  if( rc==SQLITE_OK) {
-    pPager->journalOff = szJ;
-    /* pager_reload_cache(pPager); */
+  dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+#if SQLITE_OS_WINCE
+    dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
+    isTemp = 1;
+#else
+    dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
+                               | FILE_ATTRIBUTE_HIDDEN
+                               | FILE_FLAG_DELETE_ON_CLOSE;
+#endif
+  }else{
+    dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
   }
-  return rc;
-}
-
-/*
-** Change the maximum number of in-memory pages that are allowed.
+  /* Reports from the internet are that performance is always
+  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
+#if SQLITE_OS_WINCE
+  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
+#endif
+  if( isNT() ){
+    h = CreateFileW((WCHAR*)zConverted,
+       dwDesiredAccess,
+       dwShareMode,
+       NULL,
+       dwCreationDisposition,
+       dwFlagsAndAttributes,
+       NULL
+    );
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
 */
-SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
-  if( mxPage>10 ){
-    pPager->mxPage = mxPage;
+#if SQLITE_OS_WINCE==0
   }else{
-    pPager->mxPage = 10;
+    h = CreateFileA((char*)zConverted,
+       dwDesiredAccess,
+       dwShareMode,
+       NULL,
+       dwCreationDisposition,
+       dwFlagsAndAttributes,
+       NULL
+    );
+#endif
+  }
+  if( h==INVALID_HANDLE_VALUE ){
+    free(zConverted);
+    if( flags & SQLITE_OPEN_READWRITE ){
+      return winOpen(pVfs, zName, id, 
+             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
+    }else{
+      return SQLITE_CANTOPEN;
+    }
+  }
+  if( pOutFlags ){
+    if( flags & SQLITE_OPEN_READWRITE ){
+      *pOutFlags = SQLITE_OPEN_READWRITE;
+    }else{
+      *pOutFlags = SQLITE_OPEN_READONLY;
+    }
+  }
+  memset(pFile, 0, sizeof(*pFile));
+  pFile->pMethod = &winIoMethod;
+  pFile->h = h;
+  pFile->lastErrno = NO_ERROR;
+  pFile->sectorSize = getSectorSize(pVfs, zUtf8Name);
+#if SQLITE_OS_WINCE
+  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
+               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
+       && !winceCreateLock(zName, pFile)
+  ){
+    CloseHandle(h);
+    free(zConverted);
+    return SQLITE_CANTOPEN;
   }
+  if( isTemp ){
+    pFile->zDeleteOnClose = zConverted;
+  }else
+#endif
+  {
+    free(zConverted);
+  }
+  OpenCounter(+1);
+  return SQLITE_OK;
 }
 
 /*
-** Adjust the robustness of the database to damage due to OS crashes
-** or power failures by changing the number of syncs()s when writing
-** the rollback journal.  There are three levels:
-**
-**    OFF       sqlite3OsSync() is never called.  This is the default
-**              for temporary and transient files.
-**
-**    NORMAL    The journal is synced once before writes begin on the
-**              database.  This is normally adequate protection, but
-**              it is theoretically possible, though very unlikely,
-**              that an inopertune power failure could leave the journal
-**              in a state which would cause damage to the database
-**              when it is rolled back.
-**
-**    FULL      The journal is synced twice before writes begin on the
-**              database (with some additional information - the nRec field
-**              of the journal header - being written in between the two
-**              syncs).  If we assume that writing a
-**              single disk sector is atomic, then this mode provides
-**              assurance that the journal will not be corrupted to the
-**              point of causing damage to the database during rollback.
+** Delete the named file.
 **
-** Numeric values associated with these states are OFF==1, NORMAL=2,
-** and FULL=3.
-*/
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager *pPager, int level, int full_fsync){
-  pPager->noSync =  level==1 || pPager->tempFile;
-  pPager->fullSync = level==3 && !pPager->tempFile;
-  pPager->sync_flags = (full_fsync?SQLITE_SYNC_FULL:SQLITE_SYNC_NORMAL);
-  if( pPager->noSync ) pPager->needSync = 0;
-}
-#endif
-
-/*
-** The following global variable is incremented whenever the library
-** attempts to open a temporary file.  This information is used for
-** testing and analysis only.  
+** Note that windows does not allow a file to be deleted if some other
+** process has it open.  Sometimes a virus scanner or indexing program
+** will open a journal file shortly after it is created in order to do
+** whatever it does.  While this other process is holding the
+** file open, we will be unable to delete it.  To work around this
+** problem, we delay 100 milliseconds and try to delete again.  Up
+** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
+** up and returning an error.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_opentemp_count = 0;
+#define MX_DELETION_ATTEMPTS 5
+static int winDelete(
+  sqlite3_vfs *pVfs,          /* Not used on win32 */
+  const char *zFilename,      /* Name of file to delete */
+  int syncDir                 /* Not used on win32 */
+){
+  int cnt = 0;
+  DWORD rc;
+  DWORD error = 0;
+  void *zConverted = convertUtf8Filename(zFilename);
+  UNUSED_PARAMETER(pVfs);
+  UNUSED_PARAMETER(syncDir);
+  if( zConverted==0 ){
+    return SQLITE_NOMEM;
+  }
+  SimulateIOError(return SQLITE_IOERR_DELETE);
+  if( isNT() ){
+    do{
+      DeleteFileW(zConverted);
+    }while(   (   ((rc = GetFileAttributesW(zConverted)) != INVALID_FILE_ATTRIBUTES)
+               || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
+           && (++cnt < MX_DELETION_ATTEMPTS)
+           && (Sleep(100), 1) );
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
+*/
+#if SQLITE_OS_WINCE==0
+  }else{
+    do{
+      DeleteFileA(zConverted);
+    }while(   (   ((rc = GetFileAttributesA(zConverted)) != INVALID_FILE_ATTRIBUTES)
+               || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
+           && (++cnt < MX_DELETION_ATTEMPTS)
+           && (Sleep(100), 1) );
 #endif
+  }
+  free(zConverted);
+  OSTRACE2("DELETE \"%s\"\n", zFilename);
+  return (   (rc == INVALID_FILE_ATTRIBUTES) 
+          && (error == ERROR_FILE_NOT_FOUND)) ? SQLITE_OK : SQLITE_IOERR_DELETE;
+}
 
 /*
-** Open a temporary file. 
-**
-** Write the file descriptor into *fd.  Return SQLITE_OK on success or some
-** other error code if we fail. The OS will automatically delete the temporary
-** file when it is closed.
+** Check the existance and status of a file.
 */
-static int sqlite3PagerOpentemp(
-  sqlite3_vfs *pVfs,    /* The virtual file system layer */
-  sqlite3_file *pFile,  /* Write the file descriptor here */
-  char *zFilename,      /* Name of the file.  Might be NULL */
-  int vfsFlags          /* Flags passed through to the VFS */
+static int winAccess(
+  sqlite3_vfs *pVfs,         /* Not used on win32 */
+  const char *zFilename,     /* Name of file to check */
+  int flags,                 /* Type of test to make on this file */
+  int *pResOut               /* OUT: Result */
 ){
-  int rc;
-  assert( zFilename!=0 );
-
-#ifdef SQLITE_TEST
-  sqlite3_opentemp_count++;  /* Used for testing and analysis only */
+  DWORD attr;
+  int rc = 0;
+  void *zConverted = convertUtf8Filename(zFilename);
+  UNUSED_PARAMETER(pVfs);
+  if( zConverted==0 ){
+    return SQLITE_NOMEM;
+  }
+  if( isNT() ){
+    attr = GetFileAttributesW((WCHAR*)zConverted);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
+*/
+#if SQLITE_OS_WINCE==0
+  }else{
+    attr = GetFileAttributesA((char*)zConverted);
 #endif
-
-  vfsFlags |=  SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE |
-            SQLITE_OPEN_EXCLUSIVE | SQLITE_OPEN_DELETEONCLOSE;
-  rc = sqlite3OsOpen(pVfs, zFilename, pFile, vfsFlags, 0);
-  assert( rc!=SQLITE_OK || pFile->pMethods );
-  return rc;
+  }
+  free(zConverted);
+  switch( flags ){
+    case SQLITE_ACCESS_READ:
+    case SQLITE_ACCESS_EXISTS:
+      rc = attr!=INVALID_FILE_ATTRIBUTES;
+      break;
+    case SQLITE_ACCESS_READWRITE:
+      rc = (attr & FILE_ATTRIBUTE_READONLY)==0;
+      break;
+    default:
+      assert(!"Invalid flags argument");
+  }
+  *pResOut = rc;
+  return SQLITE_OK;
 }
 
+
 /*
-** Create a new page cache and put a pointer to the page cache in *ppPager.
-** The file to be cached need not exist.  The file is not locked until
-** the first call to sqlite3PagerGet() and is only held open until the
-** last page is released using sqlite3PagerUnref().
-**
-** If zFilename is NULL then a randomly-named temporary file is created
-** and used as the file to be cached.  The file will be deleted
-** automatically when it is closed.
-**
-** If zFilename is ":memory:" then all information is held in cache.
-** It is never written to disk.  This can be used to implement an
-** in-memory database.
+** Turn a relative pathname into a full pathname.  Write the full
+** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
+** bytes in size.
 */
-SQLITE_PRIVATE int sqlite3PagerOpen(
-  sqlite3_vfs *pVfs,       /* The virtual file system to use */
-  Pager **ppPager,         /* Return the Pager structure here */
-  const char *zFilename,   /* Name of the database file to open */
-  int nExtra,              /* Extra bytes append to each in-memory page */
-  int flags,               /* flags controlling this file */
-  int vfsFlags             /* flags passed through to sqlite3_vfs.xOpen() */
+static int winFullPathname(
+  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
+  const char *zRelative,        /* Possibly relative input path */
+  int nFull,                    /* Size of output buffer in bytes */
+  char *zFull                   /* Output buffer */
 ){
-  u8 *pPtr;
-  Pager *pPager = 0;
-  int rc = SQLITE_OK;
-  int i;
-  int tempFile = 0;
-  int memDb = 0;
-  int readOnly = 0;
-  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0;
-  int noReadlock = (flags & PAGER_NO_READLOCK)!=0;
-  int journalFileSize = sqlite3JournalSize(pVfs);
-  int nDefaultPage = SQLITE_DEFAULT_PAGE_SIZE;
-  char *zPathname;
-  int nPathname;
-  char *zStmtJrnl;
-  int nStmtJrnl;
-
-  /* The default return is a NULL pointer */
-  *ppPager = 0;
+  
+#if defined(__CYGWIN__)
+  UNUSED_PARAMETER(nFull);
+  cygwin_conv_to_full_win32_path(zRelative, zFull);
+  return SQLITE_OK;
+#endif
 
-  /* Compute the full pathname */
-  nPathname = pVfs->mxPathname+1;
-  zPathname = sqlite3_malloc(nPathname*2);
-  if( zPathname==0 ){
-    return SQLITE_NOMEM;
-  }
-  if( zFilename && zFilename[0] ){
-#ifndef SQLITE_OMIT_MEMORYDB
-    if( strcmp(zFilename,":memory:")==0 ){
-      memDb = 1;
-      zPathname[0] = 0;
-    }else
+#if SQLITE_OS_WINCE
+  UNUSED_PARAMETER(nFull);
+  /* WinCE has no concept of a relative pathname, or so I am told. */
+  sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative);
+  return SQLITE_OK;
 #endif
-    {
-      rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
+
+#if !SQLITE_OS_WINCE && !defined(__CYGWIN__)
+  int nByte;
+  void *zConverted;
+  char *zOut;
+  UNUSED_PARAMETER(nFull);
+  zConverted = convertUtf8Filename(zRelative);
+  if( isNT() ){
+    WCHAR *zTemp;
+    nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3;
+    zTemp = malloc( nByte*sizeof(zTemp[0]) );
+    if( zTemp==0 ){
+      free(zConverted);
+      return SQLITE_NOMEM;
     }
+    GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0);
+    free(zConverted);
+    zOut = unicodeToUtf8(zTemp);
+    free(zTemp);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
+*/
+#if SQLITE_OS_WINCE==0
   }else{
-    rc = sqlite3OsGetTempname(pVfs, nPathname, zPathname);
-  }
-  if( rc!=SQLITE_OK ){
-    sqlite3_free(zPathname);
-    return rc;
-  }
-  nPathname = strlen(zPathname);
-
-  /* Put the statement journal in temporary disk space since this is
-  ** sometimes RAM disk or other optimized storage.  Unlikely the main
-  ** main journal file, the statement journal does not need to be 
-  ** colocated with the database nor does it need to be persistent.
-  */
-  zStmtJrnl = &zPathname[nPathname+1];
-  rc = sqlite3OsGetTempname(pVfs, pVfs->mxPathname+1, zStmtJrnl);
-  if( rc!=SQLITE_OK ){
-    sqlite3_free(zPathname);
-    return rc;
+    char *zTemp;
+    nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
+    zTemp = malloc( nByte*sizeof(zTemp[0]) );
+    if( zTemp==0 ){
+      free(zConverted);
+      return SQLITE_NOMEM;
+    }
+    GetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
+    free(zConverted);
+    zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
+    free(zTemp);
+#endif
   }
-  nStmtJrnl = strlen(zStmtJrnl);
-
-  /* Allocate memory for the pager structure */
-  pPager = sqlite3MallocZero(
-    sizeof(*pPager) +           /* Pager structure */
-    journalFileSize +           /* The journal file structure */ 
-    pVfs->szOsFile * 3 +        /* The main db and two journal files */ 
-    3*nPathname + 40 +          /* zFilename, zDirectory, zJournal */
-    nStmtJrnl                   /* zStmtJrnl */
-  );
-  if( !pPager ){
-    sqlite3_free(zPathname);
+  if( zOut ){
+    sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zOut);
+    free(zOut);
+    return SQLITE_OK;
+  }else{
     return SQLITE_NOMEM;
   }
-  pPtr = (u8 *)&pPager[1];
-  pPager->vfsFlags = vfsFlags;
-  pPager->fd = (sqlite3_file*)&pPtr[pVfs->szOsFile*0];
-  pPager->stfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*1];
-  pPager->jfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*2];
-  pPager->zFilename = (char*)&pPtr[pVfs->szOsFile*2+journalFileSize];
-  pPager->zDirectory = &pPager->zFilename[nPathname+1];
-  pPager->zJournal = &pPager->zDirectory[nPathname+1];
-  pPager->zStmtJrnl = &pPager->zJournal[nPathname+10];
-  pPager->pVfs = pVfs;
-  memcpy(pPager->zFilename, zPathname, nPathname+1);
-  memcpy(pPager->zStmtJrnl, zStmtJrnl, nStmtJrnl+1);
-  sqlite3_free(zPathname);
+#endif
+}
 
-  /* Open the pager file.
+/*
+** Get the sector size of the device used to store
+** file.
+*/
+static int getSectorSize(
+    sqlite3_vfs *pVfs,
+    const char *zRelative     /* UTF-8 file name */
+){
+  DWORD bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
+  /* GetDiskFreeSpace is not supported under WINCE */
+#if SQLITE_OS_WINCE
+  UNUSED_PARAMETER(pVfs);
+  UNUSED_PARAMETER(zRelative);
+#else
+  char zFullpath[MAX_PATH+1];
+  int rc;
+  DWORD dwRet = 0;
+  DWORD dwDummy;
+
+  /*
+  ** We need to get the full path name of the file
+  ** to get the drive letter to look up the sector
+  ** size.
   */
-  if( zFilename && zFilename[0] && !memDb ){
-    if( nPathname>(pVfs->mxPathname - sizeof("-journal")) ){
-      rc = SQLITE_CANTOPEN;
-    }else{
-      int fout = 0;
-      rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd,
-                         pPager->vfsFlags, &fout);
-      readOnly = (fout&SQLITE_OPEN_READONLY);
-
-      /* If the file was successfully opened for read/write access,
-      ** choose a default page size in case we have to create the
-      ** database file. The default page size is the maximum of:
-      **
-      **    + SQLITE_DEFAULT_PAGE_SIZE,
-      **    + The value returned by sqlite3OsSectorSize()
-      **    + The largest page size that can be written atomically.
-      */
-      if( rc==SQLITE_OK && !readOnly ){
-        int iSectorSize = sqlite3OsSectorSize(pPager->fd);
-        if( nDefaultPage<iSectorSize ){
-          nDefaultPage = iSectorSize;
-        }
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-        {
-          int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
-          int ii;
-          assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
-          assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
-          assert(SQLITE_MAX_DEFAULT_PAGE_SIZE<=65536);
-          for(ii=nDefaultPage; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
-            if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ) nDefaultPage = ii;
+  rc = winFullPathname(pVfs, zRelative, MAX_PATH, zFullpath);
+  if( rc == SQLITE_OK )
+  {
+    void *zConverted = convertUtf8Filename(zFullpath);
+    if( zConverted ){
+      if( isNT() ){
+        /* trim path to just drive reference */
+        WCHAR *p = zConverted;
+        for(;*p;p++){
+          if( *p == '\\' ){
+            *p = '\0';
+            break;
           }
         }
-#endif
-        if( nDefaultPage>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
-          nDefaultPage = SQLITE_MAX_DEFAULT_PAGE_SIZE;
+        dwRet = GetDiskFreeSpaceW((WCHAR*)zConverted,
+                                  &dwDummy,
+                                  &bytesPerSector,
+                                  &dwDummy,
+                                  &dwDummy);
+      }else{
+        /* trim path to just drive reference */
+        CHAR *p = (CHAR *)zConverted;
+        for(;*p;p++){
+          if( *p == '\\' ){
+            *p = '\0';
+            break;
+          }
         }
+        dwRet = GetDiskFreeSpaceA((CHAR*)zConverted,
+                                  &dwDummy,
+                                  &bytesPerSector,
+                                  &dwDummy,
+                                  &dwDummy);
       }
+      free(zConverted);
+    }
+    if( !dwRet ){
+      bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
     }
-  }else if( !memDb ){
-    /* If a temporary file is requested, it is not opened immediately.
-    ** In this case we accept the default page size and delay actually
-    ** opening the file until the first call to OsWrite().
-    */ 
-    tempFile = 1;
-    pPager->state = PAGER_EXCLUSIVE;
-  }
-
-  if( pPager && rc==SQLITE_OK ){
-    pPager->pTmpSpace = sqlite3MallocZero(nDefaultPage);
   }
+#endif
+  return (int) bytesPerSector; 
+}
 
-  /* If an error occured in either of the blocks above.
-  ** Free the Pager structure and close the file.
-  ** Since the pager is not allocated there is no need to set 
-  ** any Pager.errMask variables.
-  */
-  if( !pPager || !pPager->pTmpSpace ){
-    sqlite3OsClose(pPager->fd);
-    sqlite3_free(pPager);
-    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
+  HANDLE h;
+  void *zConverted = convertUtf8Filename(zFilename);
+  UNUSED_PARAMETER(pVfs);
+  if( zConverted==0 ){
+    return 0;
   }
-
-  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename);
-  IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))
-
-  /* Fill in Pager.zDirectory[] */
-  memcpy(pPager->zDirectory, pPager->zFilename, nPathname+1);
-  for(i=strlen(pPager->zDirectory); i>0 && pPager->zDirectory[i-1]!='/'; i--){}
-  if( i>0 ) pPager->zDirectory[i-1] = 0;
-
-  /* Fill in Pager.zJournal[] */
-  memcpy(pPager->zJournal, pPager->zFilename, nPathname);
-  memcpy(&pPager->zJournal[nPathname], "-journal", 9);
-
-  /* pPager->journalOpen = 0; */
-  pPager->useJournal = useJournal && !memDb;
-  pPager->noReadlock = noReadlock && readOnly;
-  /* pPager->stmtOpen = 0; */
-  /* pPager->stmtInUse = 0; */
-  /* pPager->nRef = 0; */
-  pPager->dbSize = memDb-1;
-  pPager->pageSize = nDefaultPage;
-  /* pPager->stmtSize = 0; */
-  /* pPager->stmtJSize = 0; */
-  /* pPager->nPage = 0; */
-  pPager->mxPage = 100;
-  pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
-  /* pPager->state = PAGER_UNLOCK; */
-  assert( pPager->state == (tempFile ? PAGER_EXCLUSIVE : PAGER_UNLOCK) );
-  /* pPager->errMask = 0; */
-  pPager->tempFile = tempFile;
-  assert( tempFile==PAGER_LOCKINGMODE_NORMAL 
-          || tempFile==PAGER_LOCKINGMODE_EXCLUSIVE );
-  assert( PAGER_LOCKINGMODE_EXCLUSIVE==1 );
-  pPager->exclusiveMode = tempFile; 
-  pPager->memDb = memDb;
-  pPager->readOnly = readOnly;
-  /* pPager->needSync = 0; */
-  pPager->noSync = pPager->tempFile || !useJournal;
-  pPager->fullSync = (pPager->noSync?0:1);
-  pPager->sync_flags = SQLITE_SYNC_NORMAL;
-  /* pPager->pFirst = 0; */
-  /* pPager->pFirstSynced = 0; */
-  /* pPager->pLast = 0; */
-  pPager->nExtra = FORCE_ALIGNMENT(nExtra);
-  assert(pPager->fd->pMethods||memDb||tempFile);
-  if( !memDb ){
-    setSectorSize(pPager);
-  }
-  /* pPager->pBusyHandler = 0; */
-  /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
-  *ppPager = pPager;
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  pPager->iInUseMM = 0;
-  pPager->iInUseDB = 0;
-  if( !memDb ){
-#ifndef SQLITE_MUTEX_NOOP
-    sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM2);
+  if( isNT() ){
+    h = LoadLibraryW((WCHAR*)zConverted);
+/* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed. 
+** Since the ASCII version of these Windows API do not exist for WINCE,
+** it's important to not reference them for WINCE builds.
+*/
+#if SQLITE_OS_WINCE==0
+  }else{
+    h = LoadLibraryA((char*)zConverted);
 #endif
-    sqlite3_mutex_enter(mutex);
-    pPager->pNext = sqlite3PagerList;
-    if( sqlite3PagerList ){
-      assert( sqlite3PagerList->pPrev==0 );
-      sqlite3PagerList->pPrev = pPager;
-    }
-    pPager->pPrev = 0;
-    sqlite3PagerList = pPager;
-    sqlite3_mutex_leave(mutex);
   }
-#endif
-  return SQLITE_OK;
+  free(zConverted);
+  return (void*)h;
 }
-
-/*
-** Set the busy handler function.
-*/
-SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager *pPager, BusyHandler *pBusyHandler){
-  pPager->pBusyHandler = pBusyHandler;
+static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
+  UNUSED_PARAMETER(pVfs);
+  getLastErrorMsg(nBuf, zBufOut);
 }
-
-/*
-** Set the destructor for this pager.  If not NULL, the destructor is called
-** when the reference count on each page reaches zero.  The destructor can
-** be used to clean up information in the extra segment appended to each page.
-**
-** The destructor is not called as a result sqlite3PagerClose().  
-** Destructors are only called by sqlite3PagerUnref().
-*/
-SQLITE_PRIVATE void sqlite3PagerSetDestructor(Pager *pPager, void (*xDesc)(DbPage*,int)){
-  pPager->xDestructor = xDesc;
+void (*winDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){
+  UNUSED_PARAMETER(pVfs);
+#if SQLITE_OS_WINCE
+  /* The GetProcAddressA() routine is only available on wince. */
+  return (void(*)(void))GetProcAddressA((HANDLE)pHandle, zSymbol);
+#else
+  /* All other windows platforms expect GetProcAddress() to take
+  ** an Ansi string regardless of the _UNICODE setting */
+  return (void(*)(void))GetProcAddress((HANDLE)pHandle, zSymbol);
+#endif
 }
-
-/*
-** Set the reinitializer for this pager.  If not NULL, the reinitializer
-** is called when the content of a page in cache is restored to its original
-** value as a result of a rollback.  The callback gives higher-level code
-** an opportunity to restore the EXTRA section to agree with the restored
-** page data.
-*/
-SQLITE_PRIVATE void sqlite3PagerSetReiniter(Pager *pPager, void (*xReinit)(DbPage*,int)){
-  pPager->xReiniter = xReinit;
+void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
+  UNUSED_PARAMETER(pVfs);
+  FreeLibrary((HANDLE)pHandle);
 }
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+  #define winDlOpen  0
+  #define winDlError 0
+  #define winDlSym   0
+  #define winDlClose 0
+#endif
+
 
 /*
-** Set the page size to *pPageSize. If the suggest new page size is
-** inappropriate, then an alternative page size is set to that
-** value before returning.
+** Write up to nBuf bytes of randomness into zBuf.
 */
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize){
-  int rc = SQLITE_OK;
-  u16 pageSize = *pPageSize;
-  assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
-  if( pageSize && pageSize!=pPager->pageSize 
-   && !pPager->memDb && pPager->nRef==0 
-  ){
-    char *pNew = (char *)sqlite3_malloc(pageSize);
-    if( !pNew ){
-      rc = SQLITE_NOMEM;
-    }else{
-      pagerEnter(pPager);
-      pager_reset(pPager);
-      pPager->pageSize = pageSize;
-      setSectorSize(pPager);
-      sqlite3_free(pPager->pTmpSpace);
-      pPager->pTmpSpace = pNew;
-      pagerLeave(pPager);
-    }
+static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+  int n = 0;
+  UNUSED_PARAMETER(pVfs);
+#if defined(SQLITE_TEST)
+  n = nBuf;
+  memset(zBuf, 0, nBuf);
+#else
+  if( sizeof(SYSTEMTIME)<=nBuf-n ){
+    SYSTEMTIME x;
+    GetSystemTime(&x);
+    memcpy(&zBuf[n], &x, sizeof(x));
+    n += sizeof(x);
   }
-  *pPageSize = pPager->pageSize;
-  return rc;
+  if( sizeof(DWORD)<=nBuf-n ){
+    DWORD pid = GetCurrentProcessId();
+    memcpy(&zBuf[n], &pid, sizeof(pid));
+    n += sizeof(pid);
+  }
+  if( sizeof(DWORD)<=nBuf-n ){
+    DWORD cnt = GetTickCount();
+    memcpy(&zBuf[n], &cnt, sizeof(cnt));
+    n += sizeof(cnt);
+  }
+  if( sizeof(LARGE_INTEGER)<=nBuf-n ){
+    LARGE_INTEGER i;
+    QueryPerformanceCounter(&i);
+    memcpy(&zBuf[n], &i, sizeof(i));
+    n += sizeof(i);
+  }
+#endif
+  return n;
 }
 
-/*
-** Return a pointer to the "temporary page" buffer held internally
-** by the pager.  This is a buffer that is big enough to hold the
-** entire content of a database page.  This buffer is used internally
-** during rollback and will be overwritten whenever a rollback
-** occurs.  But other modules are free to use it too, as long as
-** no rollbacks are happening.
-*/
-SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager *pPager){
-  return pPager->pTmpSpace;
-}
 
 /*
-** Attempt to set the maximum database page count if mxPage is positive. 
-** Make no changes if mxPage is zero or negative.  And never reduce the
-** maximum page count below the current size of the database.
-**
-** Regardless of mxPage, return the current maximum page count.
+** Sleep for a little while.  Return the amount of time slept.
 */
-SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
-  if( mxPage>0 ){
-    pPager->mxPgno = mxPage;
-  }
-  sqlite3PagerPagecount(pPager);
-  return pPager->mxPgno;
+static int winSleep(sqlite3_vfs *pVfs, int microsec){
+  Sleep((microsec+999)/1000);
+  UNUSED_PARAMETER(pVfs);
+  return ((microsec+999)/1000)*1000;
 }
 
 /*
-** The following set of routines are used to disable the simulated
-** I/O error mechanism.  These routines are used to avoid simulated
-** errors in places where we do not care about errors.
-**
-** Unless -DSQLITE_TEST=1 is used, these routines are all no-ops
-** and generate no code.
+** The following variable, if set to a non-zero value, becomes the result
+** returned from sqlite3OsCurrentTime().  This is used for testing.
 */
 #ifdef SQLITE_TEST
-SQLITE_API extern int sqlite3_io_error_pending;
-SQLITE_API extern int sqlite3_io_error_hit;
-static int saved_cnt;
-void disable_simulated_io_errors(void){
-  saved_cnt = sqlite3_io_error_pending;
-  sqlite3_io_error_pending = -1;
-}
-void enable_simulated_io_errors(void){
-  sqlite3_io_error_pending = saved_cnt;
-}
-#else
-# define disable_simulated_io_errors()
-# define enable_simulated_io_errors()
+SQLITE_API int sqlite3_current_time = 0;
 #endif
 
 /*
-** Read the first N bytes from the beginning of the file into memory
-** that pDest points to. 
-**
-** No error checking is done. The rational for this is that this function 
-** may be called even if the file does not exist or contain a header. In 
-** these cases sqlite3OsRead() will return an error, to which the correct 
-** response is to zero the memory at pDest and continue.  A real IO error 
-** will presumably recur and be picked up later (Todo: Think about this).
+** Find the current time (in Universal Coordinated Time).  Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0.  Return 1 if the time and date cannot be found.
 */
-SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager *pPager, int N, unsigned char *pDest){
-  int rc = SQLITE_OK;
-  memset(pDest, 0, N);
-  assert(MEMDB||pPager->fd->pMethods||pPager->tempFile);
-  if( pPager->fd->pMethods ){
-    IOTRACE(("DBHDR %p 0 %d\n", pPager, N))
-    rc = sqlite3OsRead(pPager->fd, pDest, N, 0);
-    if( rc==SQLITE_IOERR_SHORT_READ ){
-      rc = SQLITE_OK;
-    }
-  }
-  return rc;
-}
+int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
+  FILETIME ft;
+  /* FILETIME structure is a 64-bit value representing the number of 
+     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
+  */
+  sqlite3_int64 timeW;   /* Whole days */
+  sqlite3_int64 timeF;   /* Fractional Days */
 
-/*
-** Return the total number of pages in the disk file associated with
-** pPager. 
-**
-** If the PENDING_BYTE lies on the page directly after the end of the
-** file, then consider this page part of the file too. For example, if
-** PENDING_BYTE is byte 4096 (the first byte of page 5) and the size of the
-** file is 4096 bytes, 5 is returned instead of 4.
-*/
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager *pPager){
-  i64 n = 0;
-  int rc;
-  assert( pPager!=0 );
-  if( pPager->errCode ){
-    return -1;
-  }
-  if( pPager->dbSize>=0 ){
-    n = pPager->dbSize;
-  } else {
-    assert(pPager->fd->pMethods||pPager->tempFile);
-    if( (pPager->fd->pMethods)
-     && (rc = sqlite3OsFileSize(pPager->fd, &n))!=SQLITE_OK ){
-      pPager->nRef++;
-      pager_error(pPager, rc);
-      pPager->nRef--;
-      return -1;
-    }
-    if( n>0 && n<pPager->pageSize ){
-      n = 1;
-    }else{
-      n /= pPager->pageSize;
-    }
-    if( pPager->state!=PAGER_UNLOCK ){
-      pPager->dbSize = n;
-    }
-  }
-  if( n==(PENDING_BYTE/pPager->pageSize) ){
-    n++;
+  /* Number of 100-nanosecond intervals in a single day */
+  static const sqlite3_int64 ntuPerDay = 
+      10000000*(sqlite3_int64)86400;
+
+  /* Number of 100-nanosecond intervals in half of a day */
+  static const sqlite3_int64 ntuPerHalfDay = 
+      10000000*(sqlite3_int64)43200;
+
+  /* 2^32 - to avoid use of LL and warnings in gcc */
+  static const sqlite3_int64 max32BitValue = 
+      (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 + (sqlite3_int64)294967296;
+
+#if SQLITE_OS_WINCE
+  SYSTEMTIME time;
+  GetSystemTime(&time);
+  /* if SystemTimeToFileTime() fails, it returns zero. */
+  if (!SystemTimeToFileTime(&time,&ft)){
+    return 1;
   }
-  if( n>pPager->mxPgno ){
-    pPager->mxPgno = n;
+#else
+  GetSystemTimeAsFileTime( &ft );
+#endif
+  UNUSED_PARAMETER(pVfs);
+  timeW = (((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) + (sqlite3_int64)ft.dwLowDateTime;
+  timeF = timeW % ntuPerDay;          /* fractional days (100-nanoseconds) */
+  timeW = timeW / ntuPerDay;          /* whole days */
+  timeW = timeW + 2305813;            /* add whole days (from 2305813.5) */
+  timeF = timeF + ntuPerHalfDay;      /* add half a day (from 2305813.5) */
+  timeW = timeW + (timeF/ntuPerDay);  /* add whole day if half day made one */
+  timeF = timeF % ntuPerDay;          /* compute new fractional days */
+  *prNow = (double)timeW + ((double)timeF / (double)ntuPerDay);
+#ifdef SQLITE_TEST
+  if( sqlite3_current_time ){
+    *prNow = ((double)sqlite3_current_time + (double)43200) / (double)86400 + (double)2440587;
   }
-  return n;
+#endif
+  return 0;
 }
 
-
-#ifndef SQLITE_OMIT_MEMORYDB
 /*
-** Clear a PgHistory block
+** The idea is that this function works like a combination of
+** GetLastError() and FormatMessage() on windows (or errno and
+** strerror_r() on unix). After an error is returned by an OS
+** function, SQLite calls this function with zBuf pointing to
+** a buffer of nBuf bytes. The OS layer should populate the
+** buffer with a nul-terminated UTF-8 encoded error message
+** describing the last IO error to have occurred within the calling
+** thread.
+**
+** If the error message is too large for the supplied buffer,
+** it should be truncated. The return value of xGetLastError
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated). If non-zero is returned,
+** then it is not necessary to include the nul-terminator character
+** in the output buffer.
+**
+** Not supplying an error message will have no adverse effect
+** on SQLite. It is fine to have an implementation that never
+** returns an error message:
+**
+**   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+**     assert(zBuf[0]=='\0');
+**     return 0;
+**   }
+**
+** However if an error message is supplied, it will be incorporated
+** by sqlite into the error message available to the user using
+** sqlite3_errmsg(), possibly making IO errors easier to debug.
 */
-static void clearHistory(PgHistory *pHist){
-  sqlite3_free(pHist->pOrig);
-  sqlite3_free(pHist->pStmt);
-  pHist->pOrig = 0;
-  pHist->pStmt = 0;
+static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+  UNUSED_PARAMETER(pVfs);
+  return getLastErrorMsg(nBuf, zBuf);
 }
-#else
-#define clearHistory(x)
-#endif
 
 /*
-** Forward declaration
+** Initialize and deinitialize the operating system interface.
 */
-static int syncJournal(Pager*);
+SQLITE_API int sqlite3_os_init(void){
+  static sqlite3_vfs winVfs = {
+    1,                 /* iVersion */
+    sizeof(winFile),   /* szOsFile */
+    MAX_PATH,          /* mxPathname */
+    0,                 /* pNext */
+    "win32",           /* zName */
+    0,                 /* pAppData */
+ 
+    winOpen,           /* xOpen */
+    winDelete,         /* xDelete */
+    winAccess,         /* xAccess */
+    winFullPathname,   /* xFullPathname */
+    winDlOpen,         /* xDlOpen */
+    winDlError,        /* xDlError */
+    winDlSym,          /* xDlSym */
+    winDlClose,        /* xDlClose */
+    winRandomness,     /* xRandomness */
+    winSleep,          /* xSleep */
+    winCurrentTime,    /* xCurrentTime */
+    winGetLastError    /* xGetLastError */
+  };
 
-/*
-** Unlink pPg from its hash chain. Also set the page number to 0 to indicate
-** that the page is not part of any hash chain. This is required because the
-** sqlite3PagerMovepage() routine can leave a page in the 
-** pNextFree/pPrevFree list that is not a part of any hash-chain.
-*/
-static void unlinkHashChain(Pager *pPager, PgHdr *pPg){
-  if( pPg->pgno==0 ){
-    assert( pPg->pNextHash==0 && pPg->pPrevHash==0 );
-    return;
-  }
-  if( pPg->pNextHash ){
-    pPg->pNextHash->pPrevHash = pPg->pPrevHash;
-  }
-  if( pPg->pPrevHash ){
-    assert( pPager->aHash[pPg->pgno & (pPager->nHash-1)]!=pPg );
-    pPg->pPrevHash->pNextHash = pPg->pNextHash;
-  }else{
-    int h = pPg->pgno & (pPager->nHash-1);
-    pPager->aHash[h] = pPg->pNextHash;
-  }
-  if( MEMDB ){
-    clearHistory(PGHDR_TO_HIST(pPg, pPager));
-  }
-  pPg->pgno = 0;
-  pPg->pNextHash = pPg->pPrevHash = 0;
+  sqlite3_vfs_register(&winVfs, 1);
+  return SQLITE_OK; 
+}
+SQLITE_API int sqlite3_os_end(void){ 
+  return SQLITE_OK;
 }
 
+#endif /* SQLITE_OS_WIN */
+
+/************** End of os_win.c **********************************************/
+/************** Begin file bitvec.c ******************************************/
 /*
-** Unlink a page from the free list (the list of all pages where nRef==0)
-** and from its hash collision chain.
+** 2008 February 16
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements an object that represents a fixed-length
+** bitmap.  Bits are numbered starting with 1.
+**
+** A bitmap is used to record which pages of a database file have been
+** journalled during a transaction, or which pages have the "dont-write"
+** property.  Usually only a few pages are meet either condition.
+** So the bitmap is usually sparse and has low cardinality.
+** But sometimes (for example when during a DROP of a large table) most
+** or all of the pages in a database can get journalled.  In those cases, 
+** the bitmap becomes dense with high cardinality.  The algorithm needs 
+** to handle both cases well.
+**
+** The size of the bitmap is fixed when the object is created.
+**
+** All bits are clear when the bitmap is created.  Individual bits
+** may be set or cleared one at a time.
+**
+** Test operations are about 100 times more common that set operations.
+** Clear operations are exceedingly rare.  There are usually between
+** 5 and 500 set operations per Bitvec object, though the number of sets can
+** sometimes grow into tens of thousands or larger.  The size of the
+** Bitvec object is the number of pages in the database file at the
+** start of a transaction, and is thus usually less than a few thousand,
+** but can be as large as 2 billion for a really big database.
+**
+** @(#) $Id: bitvec.c,v 1.17 2009/07/25 17:33:26 drh Exp $
 */
-static void unlinkPage(PgHdr *pPg){
-  Pager *pPager = pPg->pPager;
 
-  /* Unlink from free page list */
-  lruListRemove(pPg);
+/* Size of the Bitvec structure in bytes. */
+#define BITVEC_SZ        (sizeof(void*)*128)  /* 512 on 32bit.  1024 on 64bit */
+
+/* Round the union size down to the nearest pointer boundary, since that's how 
+** it will be aligned within the Bitvec struct. */
+#define BITVEC_USIZE     (((BITVEC_SZ-(3*sizeof(u32)))/sizeof(Bitvec*))*sizeof(Bitvec*))
+
+/* Type of the array "element" for the bitmap representation. 
+** Should be a power of 2, and ideally, evenly divide into BITVEC_USIZE. 
+** Setting this to the "natural word" size of your CPU may improve
+** performance. */
+#define BITVEC_TELEM     u8
+/* Size, in bits, of the bitmap element. */
+#define BITVEC_SZELEM    8
+/* Number of elements in a bitmap array. */
+#define BITVEC_NELEM     (BITVEC_USIZE/sizeof(BITVEC_TELEM))
+/* Number of bits in the bitmap array. */
+#define BITVEC_NBIT      (BITVEC_NELEM*BITVEC_SZELEM)
+
+/* Number of u32 values in hash table. */
+#define BITVEC_NINT      (BITVEC_USIZE/sizeof(u32))
+/* Maximum number of entries in hash table before 
+** sub-dividing and re-hashing. */
+#define BITVEC_MXHASH    (BITVEC_NINT/2)
+/* Hashing function for the aHash representation.
+** Empirical testing showed that the *37 multiplier 
+** (an arbitrary prime)in the hash function provided 
+** no fewer collisions than the no-op *1. */
+#define BITVEC_HASH(X)   (((X)*1)%BITVEC_NINT)
+
+#define BITVEC_NPTR      (BITVEC_USIZE/sizeof(Bitvec *))
 
-  /* Unlink from the pgno hash table */
-  unlinkHashChain(pPager, pPg);
-}
 
 /*
-** This routine is used to truncate the cache when a database
-** is truncated.  Drop from the cache all pages whose pgno is
-** larger than pPager->dbSize and is unreferenced.
+** A bitmap is an instance of the following structure.
+**
+** This bitmap records the existance of zero or more bits
+** with values between 1 and iSize, inclusive.
+**
+** There are three possible representations of the bitmap.
+** If iSize<=BITVEC_NBIT, then Bitvec.u.aBitmap[] is a straight
+** bitmap.  The least significant bit is bit 1.
 **
-** Referenced pages larger than pPager->dbSize are zeroed.
+** If iSize>BITVEC_NBIT and iDivisor==0 then Bitvec.u.aHash[] is
+** a hash table that will hold up to BITVEC_MXHASH distinct values.
 **
-** Actually, at the point this routine is called, it would be
-** an error to have a referenced page.  But rather than delete
-** that page and guarantee a subsequent segfault, it seems better
-** to zero it and hope that we error out sanely.
+** Otherwise, the value i is redirected into one of BITVEC_NPTR
+** sub-bitmaps pointed to by Bitvec.u.apSub[].  Each subbitmap
+** handles up to iDivisor separate values of i.  apSub[0] holds
+** values between 1 and iDivisor.  apSub[1] holds values between
+** iDivisor+1 and 2*iDivisor.  apSub[N] holds values between
+** N*iDivisor+1 and (N+1)*iDivisor.  Each subbitmap is normalized
+** to hold deal with values between 1 and iDivisor.
 */
-static void pager_truncate_cache(Pager *pPager){
-  PgHdr *pPg;
-  PgHdr **ppPg;
-  int dbSize = pPager->dbSize;
-
-  ppPg = &pPager->pAll;
-  while( (pPg = *ppPg)!=0 ){
-    if( pPg->pgno<=dbSize ){
-      ppPg = &pPg->pNextAll;
-    }else if( pPg->nRef>0 ){
-      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
-      ppPg = &pPg->pNextAll;
-    }else{
-      *ppPg = pPg->pNextAll;
-      IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
-      PAGER_INCR(sqlite3_pager_pgfree_count);
-      unlinkPage(pPg);
-      makeClean(pPg);
-      sqlite3_free(pPg->pData);
-      sqlite3_free(pPg);
-      pPager->nPage--;
-    }
+struct Bitvec {
+  u32 iSize;      /* Maximum bit index.  Max iSize is 4,294,967,296. */
+  u32 nSet;       /* Number of bits that are set - only valid for aHash
+                  ** element.  Max is BITVEC_NINT.  For BITVEC_SZ of 512,
+                  ** this would be 125. */
+  u32 iDivisor;   /* Number of bits handled by each apSub[] entry. */
+                  /* Should >=0 for apSub element. */
+                  /* Max iDivisor is max(u32) / BITVEC_NPTR + 1.  */
+                  /* For a BITVEC_SZ of 512, this would be 34,359,739. */
+  union {
+    BITVEC_TELEM aBitmap[BITVEC_NELEM];    /* Bitmap representation */
+    u32 aHash[BITVEC_NINT];      /* Hash table representation */
+    Bitvec *apSub[BITVEC_NPTR];  /* Recursive representation */
+  } u;
+};
+
+/*
+** Create a new bitmap object able to handle bits between 0 and iSize,
+** inclusive.  Return a pointer to the new object.  Return NULL if 
+** malloc fails.
+*/
+SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32 iSize){
+  Bitvec *p;
+  assert( sizeof(*p)==BITVEC_SZ );
+  p = sqlite3MallocZero( sizeof(*p) );
+  if( p ){
+    p->iSize = iSize;
   }
+  return p;
 }
 
 /*
-** Try to obtain a lock on a file.  Invoke the busy callback if the lock
-** is currently not available.  Repeat until the busy callback returns
-** false or until the lock succeeds.
-**
-** Return SQLITE_OK on success and an error code if we cannot obtain
-** the lock.
+** Check to see if the i-th bit is set.  Return true or false.
+** If p is NULL (if the bitmap has not been created) or if
+** i is out of range, then return false.
 */
-static int pager_wait_on_lock(Pager *pPager, int locktype){
-  int rc;
-
-  /* The OS lock values must be the same as the Pager lock values */
-  assert( PAGER_SHARED==SHARED_LOCK );
-  assert( PAGER_RESERVED==RESERVED_LOCK );
-  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
-
-  /* If the file is currently unlocked then the size must be unknown */
-  assert( pPager->state>=PAGER_SHARED || pPager->dbSize<0 || MEMDB );
-
-  if( pPager->state>=locktype ){
-    rc = SQLITE_OK;
-  }else{
-    if( pPager->pBusyHandler ) pPager->pBusyHandler->nBusy = 0;
-    do {
-      rc = sqlite3OsLock(pPager->fd, locktype);
-    }while( rc==SQLITE_BUSY && sqlite3InvokeBusyHandler(pPager->pBusyHandler) );
-    if( rc==SQLITE_OK ){
-      pPager->state = locktype;
-      IOTRACE(("LOCK %p %d\n", pPager, locktype))
+SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec *p, u32 i){
+  if( p==0 ) return 0;
+  if( i>p->iSize || i==0 ) return 0;
+  i--;
+  while( p->iDivisor ){
+    u32 bin = i/p->iDivisor;
+    i = i%p->iDivisor;
+    p = p->u.apSub[bin];
+    if (!p) {
+      return 0;
     }
   }
-  return rc;
+  if( p->iSize<=BITVEC_NBIT ){
+    return (p->u.aBitmap[i/BITVEC_SZELEM] & (1<<(i&(BITVEC_SZELEM-1))))!=0;
+  } else{
+    u32 h = BITVEC_HASH(i++);
+    while( p->u.aHash[h] ){
+      if( p->u.aHash[h]==i ) return 1;
+      h = (h+1) % BITVEC_NINT;
+    }
+    return 0;
+  }
 }
 
 /*
-** Truncate the file to the number of pages specified.
+** Set the i-th bit.  Return 0 on success and an error code if
+** anything goes wrong.
+**
+** This routine might cause sub-bitmaps to be allocated.  Failing
+** to get the memory needed to hold the sub-bitmap is the only
+** that can go wrong with an insert, assuming p and i are valid.
+**
+** The calling function must ensure that p is a valid Bitvec object
+** and that the value for "i" is within range of the Bitvec object.
+** Otherwise the behavior is undefined.
 */
-SQLITE_PRIVATE int sqlite3PagerTruncate(Pager *pPager, Pgno nPage){
-  int rc;
-  assert( pPager->state>=PAGER_SHARED || MEMDB );
-  sqlite3PagerPagecount(pPager);
-  if( pPager->errCode ){
-    rc = pPager->errCode;
-    return rc;
-  }
-  if( nPage>=(unsigned)pPager->dbSize ){
-    return SQLITE_OK;
+SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec *p, u32 i){
+  u32 h;
+  if( p==0 ) return SQLITE_OK;
+  assert( i>0 );
+  assert( i<=p->iSize );
+  i--;
+  while((p->iSize > BITVEC_NBIT) && p->iDivisor) {
+    u32 bin = i/p->iDivisor;
+    i = i%p->iDivisor;
+    if( p->u.apSub[bin]==0 ){
+      p->u.apSub[bin] = sqlite3BitvecCreate( p->iDivisor );
+      if( p->u.apSub[bin]==0 ) return SQLITE_NOMEM;
+    }
+    p = p->u.apSub[bin];
   }
-  if( MEMDB ){
-    pPager->dbSize = nPage;
-    pager_truncate_cache(pPager);
+  if( p->iSize<=BITVEC_NBIT ){
+    p->u.aBitmap[i/BITVEC_SZELEM] |= 1 << (i&(BITVEC_SZELEM-1));
     return SQLITE_OK;
   }
-  pagerEnter(pPager);
-  rc = syncJournal(pPager);
-  pagerLeave(pPager);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  h = BITVEC_HASH(i++);
+  /* if there wasn't a hash collision, and this doesn't */
+  /* completely fill the hash, then just add it without */
+  /* worring about sub-dividing and re-hashing. */
+  if( !p->u.aHash[h] ){
+    if (p->nSet<(BITVEC_NINT-1)) {
+      goto bitvec_set_end;
+    } else {
+      goto bitvec_set_rehash;
+    }
   }
-
-  /* Get an exclusive lock on the database before truncating. */
-  pagerEnter(pPager);
-  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
-  pagerLeave(pPager);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  /* there was a collision, check to see if it's already */
+  /* in hash, if not, try to find a spot for it */
+  do {
+    if( p->u.aHash[h]==i ) return SQLITE_OK;
+    h++;
+    if( h>=BITVEC_NINT ) h = 0;
+  } while( p->u.aHash[h] );
+  /* we didn't find it in the hash.  h points to the first */
+  /* available free spot. check to see if this is going to */
+  /* make our hash too "full".  */
+bitvec_set_rehash:
+  if( p->nSet>=BITVEC_MXHASH ){
+    unsigned int j;
+    int rc;
+    u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
+    if( aiValues==0 ){
+      return SQLITE_NOMEM;
+    }else{
+      memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+      memset(p->u.apSub, 0, sizeof(p->u.apSub));
+      p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
+      rc = sqlite3BitvecSet(p, i);
+      for(j=0; j<BITVEC_NINT; j++){
+        if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
+      }
+      sqlite3StackFree(0, aiValues);
+      return rc;
+    }
   }
-
-  rc = pager_truncate(pPager, nPage);
-  return rc;
+bitvec_set_end:
+  p->nSet++;
+  p->u.aHash[h] = i;
+  return SQLITE_OK;
 }
 
 /*
-** Shutdown the page cache.  Free all memory and close all files.
-**
-** If a transaction was in progress when this routine is called, that
-** transaction is rolled back.  All outstanding pages are invalidated
-** and their memory is freed.  Any attempt to use a page associated
-** with this page cache after this function returns will likely
-** result in a coredump.
+** Clear the i-th bit.
 **
-** This function always succeeds. If a transaction is active an attempt
-** is made to roll it back. If an error occurs during the rollback 
-** a hot journal may be left in the filesystem but no error is returned
-** to the caller.
+** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
+** that BitvecClear can use to rebuilt its hash table.
 */
-SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager){
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  if( !MEMDB ){
-#ifndef SQLITE_MUTEX_NOOP
-    sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM2);
-#endif
-    sqlite3_mutex_enter(mutex);
-    if( pPager->pPrev ){
-      pPager->pPrev->pNext = pPager->pNext;
-    }else{
-      sqlite3PagerList = pPager->pNext;
-    }
-    if( pPager->pNext ){
-      pPager->pNext->pPrev = pPager->pPrev;
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
+  if( p==0 ) return;
+  assert( i>0 );
+  i--;
+  while( p->iDivisor ){
+    u32 bin = i/p->iDivisor;
+    i = i%p->iDivisor;
+    p = p->u.apSub[bin];
+    if (!p) {
+      return;
     }
-    sqlite3_mutex_leave(mutex);
-  }
-#endif
-
-  disable_simulated_io_errors();
-  sqlite3FaultBeginBenign(-1);
-  pPager->errCode = 0;
-  pPager->exclusiveMode = 0;
-  pager_reset(pPager);
-  pagerUnlockAndRollback(pPager);
-  enable_simulated_io_errors();
-  sqlite3FaultEndBenign(-1);
-  PAGERTRACE2("CLOSE %d\n", PAGERID(pPager));
-  IOTRACE(("CLOSE %p\n", pPager))
-  if( pPager->journalOpen ){
-    sqlite3OsClose(pPager->jfd);
   }
-  sqlite3BitvecDestroy(pPager->pInJournal);
-  if( pPager->stmtOpen ){
-    sqlite3OsClose(pPager->stfd);
+  if( p->iSize<=BITVEC_NBIT ){
+    p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
+  }else{
+    unsigned int j;
+    u32 *aiValues = pBuf;
+    memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+    memset(p->u.aHash, 0, sizeof(p->u.aHash));
+    p->nSet = 0;
+    for(j=0; j<BITVEC_NINT; j++){
+      if( aiValues[j] && aiValues[j]!=(i+1) ){
+        u32 h = BITVEC_HASH(aiValues[j]-1);
+        p->nSet++;
+        while( p->u.aHash[h] ){
+          h++;
+          if( h>=BITVEC_NINT ) h = 0;
+        }
+        p->u.aHash[h] = aiValues[j];
+      }
+    }
   }
-  sqlite3OsClose(pPager->fd);
-  /* Temp files are automatically deleted by the OS
-  ** if( pPager->tempFile ){
-  **   sqlite3OsDelete(pPager->zFilename);
-  ** }
-  */
-
-  sqlite3_free(pPager->aHash);
-  sqlite3_free(pPager->pTmpSpace);
-  sqlite3_free(pPager);
-  return SQLITE_OK;
 }
 
-#if !defined(NDEBUG) || defined(SQLITE_TEST)
 /*
-** Return the page number for the given page data.
+** Destroy a bitmap object.  Reclaim all memory used.
 */
-SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage *p){
-  return p->pgno;
+SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec *p){
+  if( p==0 ) return;
+  if( p->iDivisor ){
+    unsigned int i;
+    for(i=0; i<BITVEC_NPTR; i++){
+      sqlite3BitvecDestroy(p->u.apSub[i]);
+    }
+  }
+  sqlite3_free(p);
 }
-#endif
 
 /*
-** The page_ref() function increments the reference count for a page.
-** If the page is currently on the freelist (the reference count is zero) then
-** remove it from the freelist.
-**
-** For non-test systems, page_ref() is a macro that calls _page_ref()
-** online of the reference count is zero.  For test systems, page_ref()
-** is a real function so that we can set breakpoints and trace it.
+** Return the value of the iSize parameter specified when Bitvec *p
+** was created.
 */
-static void _page_ref(PgHdr *pPg){
-  if( pPg->nRef==0 ){
-    /* The page is currently on the freelist.  Remove it. */
-    lruListRemove(pPg);
-    pPg->pPager->nRef++;
-  }
-  pPg->nRef++;
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec *p){
+  return p->iSize;
 }
-#ifdef SQLITE_DEBUG
-  static void page_ref(PgHdr *pPg){
-    if( pPg->nRef==0 ){
-      _page_ref(pPg);
-    }else{
-      pPg->nRef++;
-    }
-  }
-#else
-# define page_ref(P)   ((P)->nRef==0?_page_ref(P):(void)(P)->nRef++)
-#endif
 
+#ifndef SQLITE_OMIT_BUILTIN_TEST
 /*
-** Increment the reference count for a page.  The input pointer is
-** a reference to the page data.
+** Let V[] be an array of unsigned characters sufficient to hold
+** up to N bits.  Let I be an integer between 0 and N.  0<=I<N.
+** Then the following macros can be used to set, clear, or test
+** individual bits within V.
 */
-SQLITE_PRIVATE int sqlite3PagerRef(DbPage *pPg){
-  pagerEnter(pPg->pPager);
-  page_ref(pPg);
-  pagerLeave(pPg->pPager);
-  return SQLITE_OK;
-}
+#define SETBIT(V,I)      V[I>>3] |= (1<<(I&7))
+#define CLEARBIT(V,I)    V[I>>3] &= ~(1<<(I&7))
+#define TESTBIT(V,I)     (V[I>>3]&(1<<(I&7)))!=0
 
 /*
-** Sync the journal.  In other words, make sure all the pages that have
-** been written to the journal have actually reached the surface of the
-** disk.  It is not safe to modify the original database file until after
-** the journal has been synced.  If the original database is modified before
-** the journal is synced and a power failure occurs, the unsynced journal
-** data would be lost and we would be unable to completely rollback the
-** database changes.  Database corruption would occur.
-** 
-** This routine also updates the nRec field in the header of the journal.
-** (See comments on the pager_playback() routine for additional information.)
-** If the sync mode is FULL, two syncs will occur.  First the whole journal
-** is synced, then the nRec field is updated, then a second sync occurs.
+** This routine runs an extensive test of the Bitvec code.
+**
+** The input is an array of integers that acts as a program
+** to test the Bitvec.  The integers are opcodes followed
+** by 0, 1, or 3 operands, depending on the opcode.  Another
+** opcode follows immediately after the last operand.
 **
-** For temporary databases, we do not care if we are able to rollback
-** after a power failure, so no sync occurs.
+** There are 6 opcodes numbered from 0 through 5.  0 is the
+** "halt" opcode and causes the test to end.
+**
+**    0          Halt and return the number of errors
+**    1 N S X    Set N bits beginning with S and incrementing by X
+**    2 N S X    Clear N bits beginning with S and incrementing by X
+**    3 N        Set N randomly chosen bits
+**    4 N        Clear N randomly chosen bits
+**    5 N S X    Set N bits from S increment X in array only, not in bitvec
 **
-** If the IOCAP_SEQUENTIAL flag is set for the persistent media on which
-** the database is stored, then OsSync() is never called on the journal
-** file. In this case all that is required is to update the nRec field in
-** the journal header.
+** The opcodes 1 through 4 perform set and clear operations are performed
+** on both a Bitvec object and on a linear array of bits obtained from malloc.
+** Opcode 5 works on the linear array only, not on the Bitvec.
+** Opcode 5 is used to deliberately induce a fault in order to
+** confirm that error detection works.
 **
-** This routine clears the needSync field of every page current held in
-** memory.
+** At the conclusion of the test the linear array is compared
+** against the Bitvec object.  If there are any differences,
+** an error is returned.  If they are the same, zero is returned.
+**
+** If a memory allocation error occurs, return -1.
 */
-static int syncJournal(Pager *pPager){
-  PgHdr *pPg;
-  int rc = SQLITE_OK;
-
-
-  /* Sync the journal before modifying the main database
-  ** (assuming there is a journal and it needs to be synced.)
-  */
-  if( pPager->needSync ){
-    if( !pPager->tempFile ){
-      int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
-      assert( pPager->journalOpen );
+SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int sz, int *aOp){
+  Bitvec *pBitvec = 0;
+  unsigned char *pV = 0;
+  int rc = -1;
+  int i, nx, pc, op;
+  void *pTmpSpace;
 
-      if( 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
-        /* Write the nRec value into the journal file header. If in
-        ** full-synchronous mode, sync the journal first. This ensures that
-        ** all data has really hit the disk before nRec is updated to mark
-        ** it as a candidate for rollback.
-        **
-        ** This is not required if the persistent media supports the
-        ** SAFE_APPEND property. Because in this case it is not possible 
-        ** for garbage data to be appended to the file, the nRec field
-        ** is populated with 0xFFFFFFFF when the journal header is written
-        ** and never needs to be updated.
-        */
-        i64 jrnlOff;
-        if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
-          PAGERTRACE2("SYNC journal of %d\n", PAGERID(pPager));
-          IOTRACE(("JSYNC %p\n", pPager))
-          rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags);
-          if( rc!=0 ) return rc;
-        }
+  /* Allocate the Bitvec to be tested and a linear array of
+  ** bits to act as the reference */
+  pBitvec = sqlite3BitvecCreate( sz );
+  pV = sqlite3_malloc( (sz+7)/8 + 1 );
+  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
+  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
+  memset(pV, 0, (sz+7)/8 + 1);
 
-        jrnlOff = pPager->journalHdr + sizeof(aJournalMagic);
-        IOTRACE(("JHDR %p %lld %d\n", pPager, jrnlOff, 4));
-        rc = write32bits(pPager->jfd, jrnlOff, pPager->nRec);
-        if( rc ) return rc;
+  /* NULL pBitvec tests */
+  sqlite3BitvecSet(0, 1);
+  sqlite3BitvecClear(0, 1, pTmpSpace);
+
+  /* Run the program */
+  pc = 0;
+  while( (op = aOp[pc])!=0 ){
+    switch( op ){
+      case 1:
+      case 2:
+      case 5: {
+        nx = 4;
+        i = aOp[pc+2] - 1;
+        aOp[pc+2] += aOp[pc+3];
+        break;
       }
-      if( 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
-        PAGERTRACE2("SYNC journal of %d\n", PAGERID(pPager));
-        IOTRACE(("JSYNC %p\n", pPager))
-        rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags| 
-          (pPager->sync_flags==SQLITE_SYNC_FULL?SQLITE_SYNC_DATAONLY:0)
-        );
-        if( rc!=0 ) return rc;
+      case 3:
+      case 4: 
+      default: {
+        nx = 2;
+        sqlite3_randomness(sizeof(i), &i);
+        break;
       }
-      pPager->journalStarted = 1;
     }
-    pPager->needSync = 0;
-
-    /* Erase the needSync flag from every page.
-    */
-    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-      pPg->needSync = 0;
+    if( (--aOp[pc+1]) > 0 ) nx = 0;
+    pc += nx;
+    i = (i & 0x7fffffff)%sz;
+    if( (op & 1)!=0 ){
+      SETBIT(pV, (i+1));
+      if( op!=5 ){
+        if( sqlite3BitvecSet(pBitvec, i+1) ) goto bitvec_end;
+      }
+    }else{
+      CLEARBIT(pV, (i+1));
+      sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
     }
-    lruListSetFirstSynced(pPager);
   }
 
-#ifndef NDEBUG
-  /* If the Pager.needSync flag is clear then the PgHdr.needSync
-  ** flag must also be clear for all pages.  Verify that this
-  ** invariant is true.
+  /* Test to make sure the linear array exactly matches the
+  ** Bitvec object.  Start with the assumption that they do
+  ** match (rc==0).  Change rc to non-zero if a discrepancy
+  ** is found.
   */
-  else{
-    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-      assert( pPg->needSync==0 );
+  rc = sqlite3BitvecTest(0,0) + sqlite3BitvecTest(pBitvec, sz+1)
+          + sqlite3BitvecTest(pBitvec, 0)
+          + (sqlite3BitvecSize(pBitvec) - sz);
+  for(i=1; i<=sz; i++){
+    if(  (TESTBIT(pV,i))!=sqlite3BitvecTest(pBitvec,i) ){
+      rc = i;
+      break;
     }
-    assert( pPager->lru.pFirstSynced==pPager->lru.pFirst );
   }
-#endif
 
+  /* Free allocated structure */
+bitvec_end:
+  sqlite3_free(pTmpSpace);
+  sqlite3_free(pV);
+  sqlite3BitvecDestroy(pBitvec);
   return rc;
 }
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
+
+/************** End of bitvec.c **********************************************/
+/************** Begin file pcache.c ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements that page cache.
+**
+** @(#) $Id: pcache.c,v 1.47 2009/07/25 11:46:49 danielk1977 Exp $
+*/
+
+/*
+** A complete page cache is an instance of this structure.
+*/
+struct PCache {
+  PgHdr *pDirty, *pDirtyTail;         /* List of dirty pages in LRU order */
+  PgHdr *pSynced;                     /* Last synced page in dirty page list */
+  int nRef;                           /* Number of referenced pages */
+  int nMax;                           /* Configured cache size */
+  int szPage;                         /* Size of every page in this cache */
+  int szExtra;                        /* Size of extra space for each page */
+  int bPurgeable;                     /* True if pages are on backing store */
+  int (*xStress)(void*,PgHdr*);       /* Call to try make a page clean */
+  void *pStress;                      /* Argument to xStress */
+  sqlite3_pcache *pCache;             /* Pluggable cache module */
+  PgHdr *pPage1;                      /* Reference to page 1 */
+};
+
+/*
+** Some of the assert() macros in this code are too expensive to run
+** even during normal debugging.  Use them only rarely on long-running
+** tests.  Enable the expensive asserts using the
+** -DSQLITE_ENABLE_EXPENSIVE_ASSERT=1 compile-time option.
+*/
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+# define expensive_assert(X)  assert(X)
+#else
+# define expensive_assert(X)
+#endif
+
+/********************************** Linked List Management ********************/
+
+#if !defined(NDEBUG) && defined(SQLITE_ENABLE_EXPENSIVE_ASSERT)
+/*
+** Check that the pCache->pSynced variable is set correctly. If it
+** is not, either fail an assert or return zero. Otherwise, return
+** non-zero. This is only used in debugging builds, as follows:
+**
+**   expensive_assert( pcacheCheckSynced(pCache) );
+*/
+static int pcacheCheckSynced(PCache *pCache){
+  PgHdr *p;
+  for(p=pCache->pDirtyTail; p!=pCache->pSynced; p=p->pDirtyPrev){
+    assert( p->nRef || (p->flags&PGHDR_NEED_SYNC) );
+  }
+  return (p==0 || p->nRef || (p->flags&PGHDR_NEED_SYNC)==0);
+}
+#endif /* !NDEBUG && SQLITE_ENABLE_EXPENSIVE_ASSERT */
+
+/*
+** Remove page pPage from the list of dirty pages.
+*/
+static void pcacheRemoveFromDirtyList(PgHdr *pPage){
+  PCache *p = pPage->pCache;
+
+  assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
+  assert( pPage->pDirtyPrev || pPage==p->pDirty );
+
+  /* Update the PCache1.pSynced variable if necessary. */
+  if( p->pSynced==pPage ){
+    PgHdr *pSynced = pPage->pDirtyPrev;
+    while( pSynced && (pSynced->flags&PGHDR_NEED_SYNC) ){
+      pSynced = pSynced->pDirtyPrev;
+    }
+    p->pSynced = pSynced;
+  }
+
+  if( pPage->pDirtyNext ){
+    pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
+  }else{
+    assert( pPage==p->pDirtyTail );
+    p->pDirtyTail = pPage->pDirtyPrev;
+  }
+  if( pPage->pDirtyPrev ){
+    pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
+  }else{
+    assert( pPage==p->pDirty );
+    p->pDirty = pPage->pDirtyNext;
+  }
+  pPage->pDirtyNext = 0;
+  pPage->pDirtyPrev = 0;
+
+  expensive_assert( pcacheCheckSynced(p) );
+}
+
+/*
+** Add page pPage to the head of the dirty list (PCache1.pDirty is set to
+** pPage).
+*/
+static void pcacheAddToDirtyList(PgHdr *pPage){
+  PCache *p = pPage->pCache;
+
+  assert( pPage->pDirtyNext==0 && pPage->pDirtyPrev==0 && p->pDirty!=pPage );
+
+  pPage->pDirtyNext = p->pDirty;
+  if( pPage->pDirtyNext ){
+    assert( pPage->pDirtyNext->pDirtyPrev==0 );
+    pPage->pDirtyNext->pDirtyPrev = pPage;
+  }
+  p->pDirty = pPage;
+  if( !p->pDirtyTail ){
+    p->pDirtyTail = pPage;
+  }
+  if( !p->pSynced && 0==(pPage->flags&PGHDR_NEED_SYNC) ){
+    p->pSynced = pPage;
+  }
+  expensive_assert( pcacheCheckSynced(p) );
+}
+
+/*
+** Wrapper around the pluggable caches xUnpin method. If the cache is
+** being used for an in-memory database, this function is a no-op.
+*/
+static void pcacheUnpin(PgHdr *p){
+  PCache *pCache = p->pCache;
+  if( pCache->bPurgeable ){
+    if( p->pgno==1 ){
+      pCache->pPage1 = 0;
+    }
+    sqlite3GlobalConfig.pcache.xUnpin(pCache->pCache, p, 0);
+  }
+}
+
+/*************************************************** General Interfaces ******
+**
+** Initialize and shutdown the page cache subsystem. Neither of these 
+** functions are threadsafe.
+*/
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void){
+  if( sqlite3GlobalConfig.pcache.xInit==0 ){
+    sqlite3PCacheSetDefault();
+  }
+  return sqlite3GlobalConfig.pcache.xInit(sqlite3GlobalConfig.pcache.pArg);
+}
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void){
+  if( sqlite3GlobalConfig.pcache.xShutdown ){
+    sqlite3GlobalConfig.pcache.xShutdown(sqlite3GlobalConfig.pcache.pArg);
+  }
+}
+
+/*
+** Return the size in bytes of a PCache object.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void){ return sizeof(PCache); }
+
+/*
+** Create a new PCache object. Storage space to hold the object
+** has already been allocated and is passed in as the p pointer. 
+** The caller discovers how much space needs to be allocated by 
+** calling sqlite3PcacheSize().
+*/
+SQLITE_PRIVATE void sqlite3PcacheOpen(
+  int szPage,                  /* Size of every page */
+  int szExtra,                 /* Extra space associated with each page */
+  int bPurgeable,              /* True if pages are on backing store */
+  int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
+  void *pStress,               /* Argument to xStress */
+  PCache *p                    /* Preallocated space for the PCache */
+){
+  memset(p, 0, sizeof(PCache));
+  p->szPage = szPage;
+  p->szExtra = szExtra;
+  p->bPurgeable = bPurgeable;
+  p->xStress = xStress;
+  p->pStress = pStress;
+  p->nMax = 100;
+}
+
+/*
+** Change the page size for PCache object. The caller must ensure that there
+** are no outstanding page references when this function is called.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
+  assert( pCache->nRef==0 && pCache->pDirty==0 );
+  if( pCache->pCache ){
+    sqlite3GlobalConfig.pcache.xDestroy(pCache->pCache);
+    pCache->pCache = 0;
+  }
+  pCache->szPage = szPage;
+}
+
+/*
+** Try to obtain a page from the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetch(
+  PCache *pCache,       /* Obtain the page from this cache */
+  Pgno pgno,            /* Page number to obtain */
+  int createFlag,       /* If true, create page if it does not exist already */
+  PgHdr **ppPage        /* Write the page here */
+){
+  PgHdr *pPage = 0;
+  int eCreate;
+
+  assert( pCache!=0 );
+  assert( createFlag==1 || createFlag==0 );
+  assert( pgno>0 );
+
+  /* If the pluggable cache (sqlite3_pcache*) has not been allocated,
+  ** allocate it now.
+  */
+  if( !pCache->pCache && createFlag ){
+    sqlite3_pcache *p;
+    int nByte;
+    nByte = pCache->szPage + pCache->szExtra + sizeof(PgHdr);
+    p = sqlite3GlobalConfig.pcache.xCreate(nByte, pCache->bPurgeable);
+    if( !p ){
+      return SQLITE_NOMEM;
+    }
+    sqlite3GlobalConfig.pcache.xCachesize(p, pCache->nMax);
+    pCache->pCache = p;
+  }
+
+  eCreate = createFlag * (1 + (!pCache->bPurgeable || !pCache->pDirty));
+  if( pCache->pCache ){
+    pPage = sqlite3GlobalConfig.pcache.xFetch(pCache->pCache, pgno, eCreate);
+  }
+
+  if( !pPage && eCreate==1 ){
+    PgHdr *pPg;
+
+    /* Find a dirty page to write-out and recycle. First try to find a 
+    ** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
+    ** cleared), but if that is not possible settle for any other 
+    ** unreferenced dirty page.
+    */
+    expensive_assert( pcacheCheckSynced(pCache) );
+    for(pPg=pCache->pSynced; 
+        pPg && (pPg->nRef || (pPg->flags&PGHDR_NEED_SYNC)); 
+        pPg=pPg->pDirtyPrev
+    );
+    if( !pPg ){
+      for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pDirtyPrev);
+    }
+    if( pPg ){
+      int rc;
+      rc = pCache->xStress(pCache->pStress, pPg);
+      if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
+        return rc;
+      }
+    }
+
+    pPage = sqlite3GlobalConfig.pcache.xFetch(pCache->pCache, pgno, 2);
+  }
+
+  if( pPage ){
+    if( !pPage->pData ){
+      memset(pPage, 0, sizeof(PgHdr) + pCache->szExtra);
+      pPage->pExtra = (void*)&pPage[1];
+      pPage->pData = (void *)&((char *)pPage)[sizeof(PgHdr) + pCache->szExtra];
+      pPage->pCache = pCache;
+      pPage->pgno = pgno;
+    }
+    assert( pPage->pCache==pCache );
+    assert( pPage->pgno==pgno );
+    assert( pPage->pExtra==(void *)&pPage[1] );
+
+    if( 0==pPage->nRef ){
+      pCache->nRef++;
+    }
+    pPage->nRef++;
+    if( pgno==1 ){
+      pCache->pPage1 = pPage;
+    }
+  }
+  *ppPage = pPage;
+  return (pPage==0 && eCreate) ? SQLITE_NOMEM : SQLITE_OK;
+}
+
+/*
+** Decrement the reference count on a page. If the page is clean and the
+** reference count drops to 0, then it is made elible for recycling.
+*/
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr *p){
+  assert( p->nRef>0 );
+  p->nRef--;
+  if( p->nRef==0 ){
+    PCache *pCache = p->pCache;
+    pCache->nRef--;
+    if( (p->flags&PGHDR_DIRTY)==0 ){
+      pcacheUnpin(p);
+    }else{
+      /* Move the page to the head of the dirty list. */
+      pcacheRemoveFromDirtyList(p);
+      pcacheAddToDirtyList(p);
+    }
+  }
+}
+
+/*
+** Increase the reference count of a supplied page by 1.
+*/
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr *p){
+  assert(p->nRef>0);
+  p->nRef++;
+}
+
+/*
+** Drop a page from the cache. There must be exactly one reference to the
+** page. This function deletes that reference, so after it returns the
+** page pointed to by p is invalid.
+*/
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr *p){
+  PCache *pCache;
+  assert( p->nRef==1 );
+  if( p->flags&PGHDR_DIRTY ){
+    pcacheRemoveFromDirtyList(p);
+  }
+  pCache = p->pCache;
+  pCache->nRef--;
+  if( p->pgno==1 ){
+    pCache->pPage1 = 0;
+  }
+  sqlite3GlobalConfig.pcache.xUnpin(pCache->pCache, p, 1);
+}
+
+/*
+** Make sure the page is marked as dirty. If it isn't dirty already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr *p){
+  p->flags &= ~PGHDR_DONT_WRITE;
+  assert( p->nRef>0 );
+  if( 0==(p->flags & PGHDR_DIRTY) ){
+    p->flags |= PGHDR_DIRTY;
+    pcacheAddToDirtyList( p);
+  }
+}
+
+/*
+** Make sure the page is marked as clean. If it isn't clean already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr *p){
+  if( (p->flags & PGHDR_DIRTY) ){
+    pcacheRemoveFromDirtyList(p);
+    p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC);
+    if( p->nRef==0 ){
+      pcacheUnpin(p);
+    }
+  }
+}
+
+/*
+** Make every page in the cache clean.
+*/
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache *pCache){
+  PgHdr *p;
+  while( (p = pCache->pDirty)!=0 ){
+    sqlite3PcacheMakeClean(p);
+  }
+}
+
+/*
+** Clear the PGHDR_NEED_SYNC flag from all dirty pages.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *pCache){
+  PgHdr *p;
+  for(p=pCache->pDirty; p; p=p->pDirtyNext){
+    p->flags &= ~PGHDR_NEED_SYNC;
+  }
+  pCache->pSynced = pCache->pDirtyTail;
+}
+
+/*
+** Change the page number of page p to newPgno. 
+*/
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
+  PCache *pCache = p->pCache;
+  assert( p->nRef>0 );
+  assert( newPgno>0 );
+  sqlite3GlobalConfig.pcache.xRekey(pCache->pCache, p, p->pgno, newPgno);
+  p->pgno = newPgno;
+  if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
+    pcacheRemoveFromDirtyList(p);
+    pcacheAddToDirtyList(p);
+  }
+}
+
+/*
+** Drop every cache entry whose page number is greater than "pgno". The
+** caller must ensure that there are no outstanding references to any pages
+** other than page 1 with a page number greater than pgno.
+**
+** If there is a reference to page 1 and the pgno parameter passed to this
+** function is 0, then the data area associated with page 1 is zeroed, but
+** the page object is not dropped.
+*/
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
+  if( pCache->pCache ){
+    PgHdr *p;
+    PgHdr *pNext;
+    for(p=pCache->pDirty; p; p=pNext){
+      pNext = p->pDirtyNext;
+      if( p->pgno>pgno ){
+        assert( p->flags&PGHDR_DIRTY );
+        sqlite3PcacheMakeClean(p);
+      }
+    }
+    if( pgno==0 && pCache->pPage1 ){
+      memset(pCache->pPage1->pData, 0, pCache->szPage);
+      pgno = 1;
+    }
+    sqlite3GlobalConfig.pcache.xTruncate(pCache->pCache, pgno+1);
+  }
+}
+
+/*
+** Close a cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache *pCache){
+  if( pCache->pCache ){
+    sqlite3GlobalConfig.pcache.xDestroy(pCache->pCache);
+  }
+}
+
+/* 
+** Discard the contents of the cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache *pCache){
+  sqlite3PcacheTruncate(pCache, 0);
+}
 
 /*
 ** Merge two lists of pages connected by pDirty and in pgno order.
-** Do not both fixing the pPrevDirty pointers.
+** Do not both fixing the pDirtyPrev pointers.
 */
-static PgHdr *merge_pagelist(PgHdr *pA, PgHdr *pB){
+static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB){
   PgHdr result, *pTail;
   pTail = &result;
   while( pA && pB ){
@@ -26675,20301 +29948,21449 @@ static PgHdr *merge_pagelist(PgHdr *pA, PgHdr *pB){
 
 /*
 ** Sort the list of pages in accending order by pgno.  Pages are
-** connected by pDirty pointers.  The pPrevDirty pointers are
+** connected by pDirty pointers.  The pDirtyPrev pointers are
 ** corrupted by this sort.
+**
+** Since there cannot be more than 2^31 distinct pages in a database,
+** there cannot be more than 31 buckets required by the merge sorter.
+** One extra bucket is added to catch overflow in case something
+** ever changes to make the previous sentence incorrect.
 */
-#define N_SORT_BUCKET_ALLOC 25
-#define N_SORT_BUCKET       25
-#ifdef SQLITE_TEST
-  int sqlite3_pager_n_sort_bucket = 0;
-  #undef N_SORT_BUCKET
-  #define N_SORT_BUCKET \
-   (sqlite3_pager_n_sort_bucket?sqlite3_pager_n_sort_bucket:N_SORT_BUCKET_ALLOC)
-#endif
-static PgHdr *sort_pagelist(PgHdr *pIn){
-  PgHdr *a[N_SORT_BUCKET_ALLOC], *p;
+#define N_SORT_BUCKET  32
+static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
+  PgHdr *a[N_SORT_BUCKET], *p;
   int i;
   memset(a, 0, sizeof(a));
   while( pIn ){
     p = pIn;
     pIn = p->pDirty;
     p->pDirty = 0;
-    for(i=0; i<N_SORT_BUCKET-1; i++){
+    for(i=0; ALWAYS(i<N_SORT_BUCKET-1); i++){
       if( a[i]==0 ){
         a[i] = p;
         break;
       }else{
-        p = merge_pagelist(a[i], p);
+        p = pcacheMergeDirtyList(a[i], p);
         a[i] = 0;
       }
     }
-    if( i==N_SORT_BUCKET-1 ){
-      /* Coverage: To get here, there need to be 2^(N_SORT_BUCKET) 
-      ** elements in the input list. This is possible, but impractical.
-      ** Testing this line is the point of global variable
-      ** sqlite3_pager_n_sort_bucket.
+    if( NEVER(i==N_SORT_BUCKET-1) ){
+      /* To get here, there need to be 2^(N_SORT_BUCKET) elements in
+      ** the input list.  But that is impossible.
       */
-      a[i] = merge_pagelist(a[i], p);
+      a[i] = pcacheMergeDirtyList(a[i], p);
     }
   }
   p = a[0];
   for(i=1; i<N_SORT_BUCKET; i++){
-    p = merge_pagelist(p, a[i]);
+    p = pcacheMergeDirtyList(p, a[i]);
   }
   return p;
 }
 
 /*
-** Given a list of pages (connected by the PgHdr.pDirty pointer) write
-** every one of those pages out to the database file and mark them all
-** as clean.
+** Return a list of all dirty pages in the cache, sorted by page number.
 */
-static int pager_write_pagelist(PgHdr *pList){
-  Pager *pPager;
+SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache *pCache){
   PgHdr *p;
-  int rc;
-
-  if( pList==0 ) return SQLITE_OK;
-  pPager = pList->pPager;
-
-  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
-  ** database file. If there is already an EXCLUSIVE lock, the following
-  ** calls to sqlite3OsLock() are no-ops.
-  **
-  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
-  ** through an intermediate state PENDING.   A PENDING lock prevents new
-  ** readers from attaching to the database but is unsufficient for us to
-  ** write.  The idea of a PENDING lock is to prevent new readers from
-  ** coming in while we wait for existing readers to clear.
-  **
-  ** While the pager is in the RESERVED state, the original database file
-  ** is unchanged and we can rollback without having to playback the
-  ** journal into the original database file.  Once we transition to
-  ** EXCLUSIVE, it means the database file has been changed and any rollback
-  ** will require a journal playback.
-  */
-  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  for(p=pCache->pDirty; p; p=p->pDirtyNext){
+    p->pDirty = p->pDirtyNext;
   }
+  return pcacheSortDirtyList(pCache->pDirty);
+}
 
-  pList = sort_pagelist(pList);
-  for(p=pList; p; p=p->pDirty){
-    assert( p->dirty );
-    p->dirty = 0;
-  }
-  while( pList ){
+/* 
+** Return the total number of referenced pages held by the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache *pCache){
+  return pCache->nRef;
+}
 
-    /* If the file has not yet been opened, open it now. */
-    if( !pPager->fd->pMethods ){
-      assert(pPager->tempFile);
-      rc = sqlite3PagerOpentemp(pPager->pVfs, pPager->fd, pPager->zFilename,
-                                pPager->vfsFlags);
-      if( rc ) return rc;
-    }
+/*
+** Return the number of references to the page supplied as an argument.
+*/
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr *p){
+  return p->nRef;
+}
 
-    /* If there are dirty pages in the page cache with page numbers greater
-    ** than Pager.dbSize, this means sqlite3PagerTruncate() was called to
-    ** make the file smaller (presumably by auto-vacuum code). Do not write
-    ** any such pages to the file.
-    */
-    if( pList->pgno<=pPager->dbSize ){
-      i64 offset = (pList->pgno-1)*(i64)pPager->pageSize;
-      char *pData = CODEC2(pPager, PGHDR_TO_DATA(pList), pList->pgno, 6);
-      PAGERTRACE4("STORE %d page %d hash(%08x)\n",
-                   PAGERID(pPager), pList->pgno, pager_pagehash(pList));
-      IOTRACE(("PGOUT %p %d\n", pPager, pList->pgno));
-      rc = sqlite3OsWrite(pPager->fd, pData, pPager->pageSize, offset);
-      PAGER_INCR(sqlite3_pager_writedb_count);
-      PAGER_INCR(pPager->nWrite);
-      if( pList->pgno==1 ){
-        memcpy(&pPager->dbFileVers, &pData[24], sizeof(pPager->dbFileVers));
-      }
-    }
-#ifndef NDEBUG
-    else{
-      PAGERTRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
-    }
-#endif
-    if( rc ) return rc;
-#ifdef SQLITE_CHECK_PAGES
-    pList->pageHash = pager_pagehash(pList);
-#endif
-    pList = pList->pDirty;
+/* 
+** Return the total number of pages in the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache *pCache){
+  int nPage = 0;
+  if( pCache->pCache ){
+    nPage = sqlite3GlobalConfig.pcache.xPagecount(pCache->pCache);
   }
-  return SQLITE_OK;
+  return nPage;
 }
 
+#ifdef SQLITE_TEST
 /*
-** Collect every dirty page into a dirty list and
-** return a pointer to the head of that list.  All pages are
-** collected even if they are still in use.
+** Get the suggested cache-size value.
 */
-static PgHdr *pager_get_all_dirty_pages(Pager *pPager){
-
-#ifndef NDEBUG
-  /* Verify the sanity of the dirty list when we are running
-  ** in debugging mode.  This is expensive, so do not
-  ** do this on a normal build. */
-  int n1 = 0;
-  int n2 = 0;
-  PgHdr *p;
-  for(p=pPager->pAll; p; p=p->pNextAll){ if( p->dirty ) n1++; }
-  for(p=pPager->pDirty; p; p=p->pDirty){ n2++; }
-  assert( n1==n2 );
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *pCache){
+  return pCache->nMax;
+}
 #endif
 
-  return pPager->pDirty;
+/*
+** Set the suggested cache-size value.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
+  pCache->nMax = mxPage;
+  if( pCache->pCache ){
+    sqlite3GlobalConfig.pcache.xCachesize(pCache->pCache, mxPage);
+  }
 }
 
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
 /*
-** Return 1 if there is a hot journal on the given pager.
-** A hot journal is one that needs to be played back.
-**
-** If the current size of the database file is 0 but a journal file
-** exists, that is probably an old journal left over from a prior
-** database with the same name.  Just delete the journal.
-**
-** Return negative if unable to determine the status of the journal.
-**
-** This routine does not open the journal file to examine its
-** content.  Hence, the journal might contain the name of a master
-** journal file that has been deleted, and hence not be hot.  Or
-** the header of the journal might be zeroed out.  This routine
-** does not discover these cases of a non-hot journal - if the
-** journal file exists and is not empty this routine assumes it
-** is hot.  The pager_playback() routine will discover that the
-** journal file is not really hot and will no-op.
+** For all dirty pages currently in the cache, invoke the specified
+** callback. This is only used if the SQLITE_CHECK_PAGES macro is
+** defined.
 */
-static int hasHotJournal(Pager *pPager){
-  sqlite3_vfs *pVfs = pPager->pVfs;
-  int rc;
-  if( !pPager->useJournal ) return 0;
-  if( !pPager->fd->pMethods ) return 0;
-  rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS);
-  if( rc<=0 ){
-    return rc;
-  }
-  if( sqlite3OsCheckReservedLock(pPager->fd) ){
-    return 0;
-  }
-  if( sqlite3PagerPagecount(pPager)==0 ){
-    sqlite3OsDelete(pVfs, pPager->zJournal, 0);
-    return 0;
-  }else{
-    return 1;
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *)){
+  PgHdr *pDirty;
+  for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext){
+    xIter(pDirty);
   }
 }
+#endif
 
+/************** End of pcache.c **********************************************/
+/************** Begin file pcache1.c *****************************************/
 /*
-** Try to find a page in the cache that can be recycled. 
+** 2008 November 05
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements the default page cache implementation (the
+** sqlite3_pcache interface). It also contains part of the implementation
+** of the SQLITE_CONFIG_PAGECACHE and sqlite3_release_memory() features.
+** If the default page cache implementation is overriden, then neither of
+** these two features are available.
 **
-** This routine may return SQLITE_IOERR, SQLITE_FULL or SQLITE_OK. It 
-** does not set the pPager->errCode variable.
+** @(#) $Id: pcache1.c,v 1.19 2009/07/17 11:44:07 drh Exp $
 */
-static int pager_recycle(Pager *pPager, PgHdr **ppPg){
-  PgHdr *pPg;
-  *ppPg = 0;
 
-  /* It is illegal to call this function unless the pager object
-  ** pointed to by pPager has at least one free page (page with nRef==0).
-  */ 
-  assert(!MEMDB);
-  assert(pPager->lru.pFirst);
 
-  /* Find a page to recycle.  Try to locate a page that does not
-  ** require us to do an fsync() on the journal.
+typedef struct PCache1 PCache1;
+typedef struct PgHdr1 PgHdr1;
+typedef struct PgFreeslot PgFreeslot;
+
+/* Pointers to structures of this type are cast and returned as 
+** opaque sqlite3_pcache* handles
+*/
+struct PCache1 {
+  /* Cache configuration parameters. Page size (szPage) and the purgeable
+  ** flag (bPurgeable) are set when the cache is created. nMax may be 
+  ** modified at any time by a call to the pcache1CacheSize() method.
+  ** The global mutex must be held when accessing nMax.
   */
-  pPg = pPager->lru.pFirstSynced;
+  int szPage;                         /* Size of allocated pages in bytes */
+  int bPurgeable;                     /* True if cache is purgeable */
+  unsigned int nMin;                  /* Minimum number of pages reserved */
+  unsigned int nMax;                  /* Configured "cache_size" value */
 
-  /* If we could not find a page that does not require an fsync()
-  ** on the journal file then fsync the journal file.  This is a
-  ** very slow operation, so we work hard to avoid it.  But sometimes
-  ** it can't be helped.
+  /* Hash table of all pages. The following variables may only be accessed
+  ** when the accessor is holding the global mutex (see pcache1EnterMutex() 
+  ** and pcache1LeaveMutex()).
   */
-  if( pPg==0 && pPager->lru.pFirst){
-    int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
-    int rc = syncJournal(pPager);
-    if( rc!=0 ){
-      return rc;
+  unsigned int nRecyclable;           /* Number of pages in the LRU list */
+  unsigned int nPage;                 /* Total number of pages in apHash */
+  unsigned int nHash;                 /* Number of slots in apHash[] */
+  PgHdr1 **apHash;                    /* Hash table for fast lookup by key */
+
+  unsigned int iMaxKey;               /* Largest key seen since xTruncate() */
+};
+
+/*
+** Each cache entry is represented by an instance of the following 
+** structure. A buffer of PgHdr1.pCache->szPage bytes is allocated 
+** directly before this structure in memory (see the PGHDR1_TO_PAGE() 
+** macro below).
+*/
+struct PgHdr1 {
+  unsigned int iKey;             /* Key value (page number) */
+  PgHdr1 *pNext;                 /* Next in hash table chain */
+  PCache1 *pCache;               /* Cache that currently owns this page */
+  PgHdr1 *pLruNext;              /* Next in LRU list of unpinned pages */
+  PgHdr1 *pLruPrev;              /* Previous in LRU list of unpinned pages */
+};
+
+/*
+** Free slots in the allocator used to divide up the buffer provided using
+** the SQLITE_CONFIG_PAGECACHE mechanism.
+*/
+struct PgFreeslot {
+  PgFreeslot *pNext;  /* Next free slot */
+};
+
+/*
+** Global data used by this cache.
+*/
+static SQLITE_WSD struct PCacheGlobal {
+  sqlite3_mutex *mutex;               /* static mutex MUTEX_STATIC_LRU */
+
+  int nMaxPage;                       /* Sum of nMaxPage for purgeable caches */
+  int nMinPage;                       /* Sum of nMinPage for purgeable caches */
+  int nCurrentPage;                   /* Number of purgeable pages allocated */
+  PgHdr1 *pLruHead, *pLruTail;        /* LRU list of unpinned pages */
+
+  /* Variables related to SQLITE_CONFIG_PAGECACHE settings. */
+  int szSlot;                         /* Size of each free slot */
+  void *pStart, *pEnd;                /* Bounds of pagecache malloc range */
+  PgFreeslot *pFree;                  /* Free page blocks */
+  int isInit;                         /* True if initialized */
+} pcache1_g;
+
+/*
+** All code in this file should access the global structure above via the
+** alias "pcache1". This ensures that the WSD emulation is used when
+** compiling for systems that do not support real WSD.
+*/
+#define pcache1 (GLOBAL(struct PCacheGlobal, pcache1_g))
+
+/*
+** When a PgHdr1 structure is allocated, the associated PCache1.szPage
+** bytes of data are located directly before it in memory (i.e. the total
+** size of the allocation is sizeof(PgHdr1)+PCache1.szPage byte). The
+** PGHDR1_TO_PAGE() macro takes a pointer to a PgHdr1 structure as
+** an argument and returns a pointer to the associated block of szPage
+** bytes. The PAGE_TO_PGHDR1() macro does the opposite: its argument is
+** a pointer to a block of szPage bytes of data and the return value is
+** a pointer to the associated PgHdr1 structure.
+**
+**   assert( PGHDR1_TO_PAGE(PAGE_TO_PGHDR1(pCache, X))==X );
+*/
+#define PGHDR1_TO_PAGE(p)    (void*)(((char*)p) - p->pCache->szPage)
+#define PAGE_TO_PGHDR1(c, p) (PgHdr1*)(((char*)p) + c->szPage)
+
+/*
+** Macros to enter and leave the global LRU mutex.
+*/
+#define pcache1EnterMutex() sqlite3_mutex_enter(pcache1.mutex)
+#define pcache1LeaveMutex() sqlite3_mutex_leave(pcache1.mutex)
+
+/******************************************************************************/
+/******** Page Allocation/SQLITE_CONFIG_PCACHE Related Functions **************/
+
+/*
+** This function is called during initialization if a static buffer is 
+** supplied to use for the page-cache by passing the SQLITE_CONFIG_PAGECACHE
+** verb to sqlite3_config(). Parameter pBuf points to an allocation large
+** enough to contain 'n' buffers of 'sz' bytes each.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *pBuf, int sz, int n){
+  if( pcache1.isInit ){
+    PgFreeslot *p;
+    sz = ROUNDDOWN8(sz);
+    pcache1.szSlot = sz;
+    pcache1.pStart = pBuf;
+    pcache1.pFree = 0;
+    while( n-- ){
+      p = (PgFreeslot*)pBuf;
+      p->pNext = pcache1.pFree;
+      pcache1.pFree = p;
+      pBuf = (void*)&((char*)pBuf)[sz];
     }
-    if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
-      /* If in full-sync mode, write a new journal header into the
-      ** journal file. This is done to avoid ever modifying a journal
-      ** header that is involved in the rollback of pages that have
-      ** already been written to the database (in case the header is
-      ** trashed when the nRec field is updated).
-      */
-      pPager->nRec = 0;
-      assert( pPager->journalOff > 0 );
-      assert( pPager->doNotSync==0 );
-      rc = writeJournalHdr(pPager);
-      if( rc!=0 ){
-        return rc;
-      }
+    pcache1.pEnd = pBuf;
+  }
+}
+
+/*
+** Malloc function used within this file to allocate space from the buffer
+** configured using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no 
+** such buffer exists or there is no space left in it, this function falls 
+** back to sqlite3Malloc().
+*/
+static void *pcache1Alloc(int nByte){
+  void *p;
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( nByte<=pcache1.szSlot && pcache1.pFree ){
+    assert( pcache1.isInit );
+    p = (PgHdr1 *)pcache1.pFree;
+    pcache1.pFree = pcache1.pFree->pNext;
+    sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+    sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_USED, 1);
+  }else{
+
+    /* Allocate a new buffer using sqlite3Malloc. Before doing so, exit the
+    ** global pcache mutex and unlock the pager-cache object pCache. This is 
+    ** so that if the attempt to allocate a new buffer causes the the 
+    ** configured soft-heap-limit to be breached, it will be possible to
+    ** reclaim memory from this pager-cache.
+    */
+    pcache1LeaveMutex();
+    p = sqlite3Malloc(nByte);
+    pcache1EnterMutex();
+    if( p ){
+      int sz = sqlite3MallocSize(p);
+      sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_OVERFLOW, sz);
     }
-    pPg = pPager->lru.pFirst;
   }
+  return p;
+}
 
-  assert( pPg->nRef==0 );
+/*
+** Free an allocated buffer obtained from pcache1Alloc().
+*/
+static void pcache1Free(void *p){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( p==0 ) return;
+  if( p>=pcache1.pStart && p<pcache1.pEnd ){
+    PgFreeslot *pSlot;
+    sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_USED, -1);
+    pSlot = (PgFreeslot*)p;
+    pSlot->pNext = pcache1.pFree;
+    pcache1.pFree = pSlot;
+  }else{
+    int iSize = sqlite3MallocSize(p);
+    sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_OVERFLOW, -iSize);
+    sqlite3_free(p);
+  }
+}
 
-  /* Write the page to the database file if it is dirty.
-  */
-  if( pPg->dirty ){
-    int rc;
-    assert( pPg->needSync==0 );
-    makeClean(pPg);
-    pPg->dirty = 1;
-    pPg->pDirty = 0;
-    rc = pager_write_pagelist( pPg );
-    pPg->dirty = 0;
-    if( rc!=SQLITE_OK ){
-      return rc;
+/*
+** Allocate a new page object initially associated with cache pCache.
+*/
+static PgHdr1 *pcache1AllocPage(PCache1 *pCache){
+  int nByte = sizeof(PgHdr1) + pCache->szPage;
+  void *pPg = pcache1Alloc(nByte);
+  PgHdr1 *p;
+  if( pPg ){
+    p = PAGE_TO_PGHDR1(pCache, pPg);
+    if( pCache->bPurgeable ){
+      pcache1.nCurrentPage++;
     }
+  }else{
+    p = 0;
   }
-  assert( pPg->dirty==0 );
+  return p;
+}
 
-  /* If the page we are recycling is marked as alwaysRollback, then
-  ** set the global alwaysRollback flag, thus disabling the
-  ** sqlite3PagerDontRollback() optimization for the rest of this transaction.
-  ** It is necessary to do this because the page marked alwaysRollback
-  ** might be reloaded at a later time but at that point we won't remember
-  ** that is was marked alwaysRollback.  This means that all pages must
-  ** be marked as alwaysRollback from here on out.
-  */
-  if( pPg->alwaysRollback ){
-    IOTRACE(("ALWAYS_ROLLBACK %p\n", pPager))
-    pPager->alwaysRollback = 1;
+/*
+** Free a page object allocated by pcache1AllocPage().
+**
+** The pointer is allowed to be NULL, which is prudent.  But it turns out
+** that the current implementation happens to never call this routine
+** with a NULL pointer, so we mark the NULL test with ALWAYS().
+*/
+static void pcache1FreePage(PgHdr1 *p){
+  if( ALWAYS(p) ){
+    if( p->pCache->bPurgeable ){
+      pcache1.nCurrentPage--;
+    }
+    pcache1Free(PGHDR1_TO_PAGE(p));
   }
+}
 
-  /* Unlink the old page from the free list and the hash table
-  */
-  unlinkPage(pPg);
-  assert( pPg->pgno==0 );
+/*
+** Malloc function used by SQLite to obtain space from the buffer configured
+** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
+** exists, this function falls back to sqlite3Malloc().
+*/
+SQLITE_PRIVATE void *sqlite3PageMalloc(int sz){
+  void *p;
+  pcache1EnterMutex();
+  p = pcache1Alloc(sz);
+  pcache1LeaveMutex();
+  return p;
+}
 
-  *ppPg = pPg;
-  return SQLITE_OK;
+/*
+** Free an allocated buffer obtained from sqlite3PageMalloc().
+*/
+SQLITE_PRIVATE void sqlite3PageFree(void *p){
+  pcache1EnterMutex();
+  pcache1Free(p);
+  pcache1LeaveMutex();
 }
 
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/******************************************************************************/
+/******** General Implementation Functions ************************************/
+
 /*
-** This function is called to free superfluous dynamically allocated memory
-** held by the pager system. Memory in use by any SQLite pager allocated
-** by the current thread may be sqlite3_free()ed.
+** This function is used to resize the hash table used by the cache passed
+** as the first argument.
 **
-** nReq is the number of bytes of memory required. Once this much has
-** been released, the function returns. The return value is the total number 
-** of bytes of memory released.
+** The global mutex must be held when this function is called.
 */
-SQLITE_PRIVATE int sqlite3PagerReleaseMemory(int nReq){
-  int nReleased = 0;          /* Bytes of memory released so far */
-  Pager *pPager;              /* For looping over pagers */
-  BusyHandler *savedBusy;     /* Saved copy of the busy handler */
-  int rc = SQLITE_OK;
+static int pcache1ResizeHash(PCache1 *p){
+  PgHdr1 **apNew;
+  unsigned int nNew;
+  unsigned int i;
 
-  /* Acquire the memory-management mutex
-  */
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex;       /* The MEM2 mutex */
-  mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM2);
-#endif
-  sqlite3_mutex_enter(mutex);
+  assert( sqlite3_mutex_held(pcache1.mutex) );
 
-  /* Signal all database connections that memory management wants
-  ** to have access to the pagers.
-  */
-  for(pPager=sqlite3PagerList; pPager; pPager=pPager->pNext){
-     pPager->iInUseMM = 1;
+  nNew = p->nHash*2;
+  if( nNew<256 ){
+    nNew = 256;
   }
 
-  while( rc==SQLITE_OK && (nReq<0 || nReleased<nReq) ){
-    PgHdr *pPg;
-    PgHdr *pRecycled;
- 
-    /* Try to find a page to recycle that does not require a sync(). If
-    ** this is not possible, find one that does require a sync().
-    */
-    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
-    pPg = sqlite3LruPageList.pFirstSynced;
-    while( pPg && (pPg->needSync || pPg->pPager->iInUseDB) ){
-      pPg = pPg->gfree.pNext;
-    }
-    if( !pPg ){
-      pPg = sqlite3LruPageList.pFirst;
-      while( pPg && pPg->pPager->iInUseDB ){
-        pPg = pPg->gfree.pNext;
+  pcache1LeaveMutex();
+  if( p->nHash ){ sqlite3BeginBenignMalloc(); }
+  apNew = (PgHdr1 **)sqlite3_malloc(sizeof(PgHdr1 *)*nNew);
+  if( p->nHash ){ sqlite3EndBenignMalloc(); }
+  pcache1EnterMutex();
+  if( apNew ){
+    memset(apNew, 0, sizeof(PgHdr1 *)*nNew);
+    for(i=0; i<p->nHash; i++){
+      PgHdr1 *pPage;
+      PgHdr1 *pNext = p->apHash[i];
+      while( (pPage = pNext)!=0 ){
+        unsigned int h = pPage->iKey % nNew;
+        pNext = pPage->pNext;
+        pPage->pNext = apNew[h];
+        apNew[h] = pPage;
       }
     }
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU));
+    sqlite3_free(p->apHash);
+    p->apHash = apNew;
+    p->nHash = nNew;
+  }
 
-    /* If pPg==0, then the block above has failed to find a page to
-    ** recycle. In this case return early - no further memory will
-    ** be released.
-    */
-    if( !pPg ) break;
+  return (p->apHash ? SQLITE_OK : SQLITE_NOMEM);
+}
 
-    pPager = pPg->pPager;
-    assert(!pPg->needSync || pPg==pPager->lru.pFirst);
-    assert(pPg->needSync || pPg==pPager->lru.pFirstSynced);
-  
-    savedBusy = pPager->pBusyHandler;
-    pPager->pBusyHandler = 0;
-    rc = pager_recycle(pPager, &pRecycled);
-    pPager->pBusyHandler = savedBusy;
-    assert(pRecycled==pPg || rc!=SQLITE_OK);
-    if( rc==SQLITE_OK ){
-      /* We've found a page to free. At this point the page has been 
-      ** removed from the page hash-table, free-list and synced-list 
-      ** (pFirstSynced). It is still in the all pages (pAll) list. 
-      ** Remove it from this list before freeing.
-      **
-      ** Todo: Check the Pager.pStmt list to make sure this is Ok. It 
-      ** probably is though.
-      */
-      PgHdr *pTmp;
-      assert( pPg );
-      if( pPg==pPager->pAll ){
-         pPager->pAll = pPg->pNextAll;
-      }else{
-        for( pTmp=pPager->pAll; pTmp->pNextAll!=pPg; pTmp=pTmp->pNextAll ){}
-        pTmp->pNextAll = pPg->pNextAll;
-      }
-      nReleased += (
-          sizeof(*pPg) + pPager->pageSize
-          + sizeof(u32) + pPager->nExtra
-          + MEMDB*sizeof(PgHistory) 
-      );
-      IOTRACE(("PGFREE %p %d *\n", pPager, pPg->pgno));
-      PAGER_INCR(sqlite3_pager_pgfree_count);
-      sqlite3_free(pPg->pData);
-      sqlite3_free(pPg);
-      pPager->nPage--;
-    }else{
-      /* An error occured whilst writing to the database file or 
-      ** journal in pager_recycle(). The error is not returned to the 
-      ** caller of this function. Instead, set the Pager.errCode variable.
-      ** The error will be returned to the user (or users, in the case 
-      ** of a shared pager cache) of the pager for which the error occured.
-      */
-      assert(
-          (rc&0xff)==SQLITE_IOERR ||
-          rc==SQLITE_FULL ||
-          rc==SQLITE_BUSY
-      );
-      assert( pPager->state>=PAGER_RESERVED );
-      pager_error(pPager, rc);
+/*
+** This function is used internally to remove the page pPage from the 
+** global LRU list, if is part of it. If pPage is not part of the global
+** LRU list, then this function is a no-op.
+**
+** The global mutex must be held when this function is called.
+*/
+static void pcache1PinPage(PgHdr1 *pPage){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( pPage && (pPage->pLruNext || pPage==pcache1.pLruTail) ){
+    if( pPage->pLruPrev ){
+      pPage->pLruPrev->pLruNext = pPage->pLruNext;
+    }
+    if( pPage->pLruNext ){
+      pPage->pLruNext->pLruPrev = pPage->pLruPrev;
+    }
+    if( pcache1.pLruHead==pPage ){
+      pcache1.pLruHead = pPage->pLruNext;
+    }
+    if( pcache1.pLruTail==pPage ){
+      pcache1.pLruTail = pPage->pLruPrev;
     }
+    pPage->pLruNext = 0;
+    pPage->pLruPrev = 0;
+    pPage->pCache->nRecyclable--;
   }
+}
 
-  /* Clear the memory management flags and release the mutex
-  */
-  for(pPager=sqlite3PagerList; pPager; pPager=pPager->pNext){
-     pPager->iInUseMM = 0;
-  }
-  sqlite3_mutex_leave(mutex);
 
-  /* Return the number of bytes released
-  */
-  return nReleased;
+/*
+** Remove the page supplied as an argument from the hash table 
+** (PCache1.apHash structure) that it is currently stored in.
+**
+** The global mutex must be held when this function is called.
+*/
+static void pcache1RemoveFromHash(PgHdr1 *pPage){
+  unsigned int h;
+  PCache1 *pCache = pPage->pCache;
+  PgHdr1 **pp;
+
+  h = pPage->iKey % pCache->nHash;
+  for(pp=&pCache->apHash[h]; (*pp)!=pPage; pp=&(*pp)->pNext);
+  *pp = (*pp)->pNext;
+
+  pCache->nPage--;
 }
-#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
 
 /*
-** Read the content of page pPg out of the database file.
+** If there are currently more than pcache.nMaxPage pages allocated, try
+** to recycle pages to reduce the number allocated to pcache.nMaxPage.
 */
-static int readDbPage(Pager *pPager, PgHdr *pPg, Pgno pgno){
-  int rc;
-  i64 offset;
-  assert( MEMDB==0 );
-  assert(pPager->fd->pMethods||pPager->tempFile);
-  if( !pPager->fd->pMethods ){
-    return SQLITE_IOERR_SHORT_READ;
-  }
-  offset = (pgno-1)*(i64)pPager->pageSize;
-  rc = sqlite3OsRead(pPager->fd, PGHDR_TO_DATA(pPg), pPager->pageSize, offset);
-  PAGER_INCR(sqlite3_pager_readdb_count);
-  PAGER_INCR(pPager->nRead);
-  IOTRACE(("PGIN %p %d\n", pPager, pgno));
-  if( pgno==1 ){
-    memcpy(&pPager->dbFileVers, &((u8*)PGHDR_TO_DATA(pPg))[24],
-                                              sizeof(pPager->dbFileVers));
+static void pcache1EnforceMaxPage(void){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  while( pcache1.nCurrentPage>pcache1.nMaxPage && pcache1.pLruTail ){
+    PgHdr1 *p = pcache1.pLruTail;
+    pcache1PinPage(p);
+    pcache1RemoveFromHash(p);
+    pcache1FreePage(p);
   }
-  CODEC1(pPager, PGHDR_TO_DATA(pPg), pPg->pgno, 3);
-  PAGERTRACE4("FETCH %d page %d hash(%08x)\n",
-               PAGERID(pPager), pPg->pgno, pager_pagehash(pPg));
-  return rc;
 }
 
-
 /*
-** This function is called to obtain the shared lock required before
-** data may be read from the pager cache. If the shared lock has already
-** been obtained, this function is a no-op.
+** Discard all pages from cache pCache with a page number (key value) 
+** greater than or equal to iLimit. Any pinned pages that meet this 
+** criteria are unpinned before they are discarded.
 **
-** Immediately after obtaining the shared lock (if required), this function
-** checks for a hot-journal file. If one is found, an emergency rollback
-** is performed immediately.
+** The global mutex must be held when this function is called.
 */
-static int pagerSharedLock(Pager *pPager){
-  int rc = SQLITE_OK;
-  int isHot = 0;
-
-  /* If this database is opened for exclusive access, has no outstanding 
-  ** page references and is in an error-state, now is the chance to clear
-  ** the error. Discard the contents of the pager-cache and treat any
-  ** open journal file as a hot-journal.
-  */
-  if( !MEMDB && pPager->exclusiveMode && pPager->nRef==0 && pPager->errCode ){
-    if( pPager->journalOpen ){
-      isHot = 1;
+static void pcache1TruncateUnsafe(
+  PCache1 *pCache, 
+  unsigned int iLimit 
+){
+  TESTONLY( unsigned int nPage = 0; )      /* Used to assert pCache->nPage is correct */
+  unsigned int h;
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  for(h=0; h<pCache->nHash; h++){
+    PgHdr1 **pp = &pCache->apHash[h]; 
+    PgHdr1 *pPage;
+    while( (pPage = *pp)!=0 ){
+      if( pPage->iKey>=iLimit ){
+        pCache->nPage--;
+        *pp = pPage->pNext;
+        pcache1PinPage(pPage);
+        pcache1FreePage(pPage);
+      }else{
+        pp = &pPage->pNext;
+        TESTONLY( nPage++; )
+      }
     }
-    pPager->errCode = SQLITE_OK;
-    pager_reset(pPager);
   }
+  assert( pCache->nPage==nPage );
+}
 
-  /* If the pager is still in an error state, do not proceed. The error 
-  ** state will be cleared at some point in the future when all page 
-  ** references are dropped and the cache can be discarded.
-  */
-  if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
-    return pPager->errCode;
-  }
+/******************************************************************************/
+/******** sqlite3_pcache Methods **********************************************/
 
-  if( pPager->state==PAGER_UNLOCK || isHot ){
-    sqlite3_vfs *pVfs = pPager->pVfs;
-    if( !MEMDB ){
-      assert( pPager->nRef==0 );
-      if( !pPager->noReadlock ){
-        rc = pager_wait_on_lock(pPager, SHARED_LOCK);
-        if( rc!=SQLITE_OK ){
-          assert( pPager->state==PAGER_UNLOCK );
-          return pager_error(pPager, rc);
-        }
-        assert( pPager->state>=SHARED_LOCK );
-      }
-  
-      /* If a journal file exists, and there is no RESERVED lock on the
-      ** database file, then it either needs to be played back or deleted.
-      */
-      rc = hasHotJournal(pPager);
-      if( rc<0 ){
-        rc = SQLITE_IOERR_NOMEM;
-        goto failed;
-      }
-      if( rc==1 || isHot ){
-        /* Get an EXCLUSIVE lock on the database file. At this point it is
-        ** important that a RESERVED lock is not obtained on the way to the
-        ** EXCLUSIVE lock. If it were, another process might open the
-        ** database file, detect the RESERVED lock, and conclude that the
-        ** database is safe to read while this process is still rolling it 
-        ** back.
-        ** 
-        ** Because the intermediate RESERVED lock is not requested, the
-        ** second process will get to this point in the code and fail to
-        ** obtain its own EXCLUSIVE lock on the database file.
-        */
-        if( pPager->state<EXCLUSIVE_LOCK ){
-          rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
-          if( rc!=SQLITE_OK ){
-            rc = pager_error(pPager, rc);
-            goto failed;
-          }
-          pPager->state = PAGER_EXCLUSIVE;
-        }
- 
-        /* Open the journal for read/write access. This is because in 
-        ** exclusive-access mode the file descriptor will be kept open and
-        ** possibly used for a transaction later on. On some systems, the
-        ** OsTruncate() call used in exclusive-access mode also requires
-        ** a read/write file handle.
-        */
-        if( !isHot && pPager->journalOpen==0 ){
-          int res = sqlite3OsAccess(pVfs,pPager->zJournal,SQLITE_ACCESS_EXISTS);
-          if( res==1 ){
-            int fout = 0;
-            int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
-            assert( !pPager->tempFile );
-            rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
-            assert( rc!=SQLITE_OK || pPager->jfd->pMethods );
-            if( fout&SQLITE_OPEN_READONLY ){
-              rc = SQLITE_BUSY;
-              sqlite3OsClose(pPager->jfd);
-            }
-          }else if( res==0 ){
-            /* If the journal does not exist, that means some other process
-            ** has already rolled it back */
-            rc = SQLITE_BUSY;
-          }else{
-            /* If sqlite3OsAccess() returns a negative value, that means it
-            ** failed a memory allocation */
-            rc = SQLITE_IOERR_NOMEM;
-          }
-        }
-        if( rc!=SQLITE_OK ){
-          if( rc!=SQLITE_NOMEM && rc!=SQLITE_IOERR_UNLOCK 
-           && rc!=SQLITE_IOERR_NOMEM 
-          ){
-            rc = SQLITE_BUSY;
-          }
-          goto failed;
-        }
-        pPager->journalOpen = 1;
-        pPager->journalStarted = 0;
-        pPager->journalOff = 0;
-        pPager->setMaster = 0;
-        pPager->journalHdr = 0;
- 
-        /* Playback and delete the journal.  Drop the database write
-        ** lock and reacquire the read lock.
-        */
-        rc = pager_playback(pPager, 1);
-        if( rc!=SQLITE_OK ){
-          rc = pager_error(pPager, rc);
-          goto failed;
-        }
-        assert(pPager->state==PAGER_SHARED || 
-            (pPager->exclusiveMode && pPager->state>PAGER_SHARED)
-        );
-      }
-
-      if( pPager->pAll ){
-        /* The shared-lock has just been acquired on the database file
-        ** and there are already pages in the cache (from a previous
-        ** read or write transaction).  Check to see if the database
-        ** has been modified.  If the database has changed, flush the
-        ** cache.
-        **
-        ** Database changes is detected by looking at 15 bytes beginning
-        ** at offset 24 into the file.  The first 4 of these 16 bytes are
-        ** a 32-bit counter that is incremented with each change.  The
-        ** other bytes change randomly with each file change when
-        ** a codec is in use.
-        ** 
-        ** There is a vanishingly small chance that a change will not be 
-        ** detected.  The chance of an undetected change is so small that
-        ** it can be neglected.
-        */
-        char dbFileVers[sizeof(pPager->dbFileVers)];
-        sqlite3PagerPagecount(pPager);
+/*
+** Implementation of the sqlite3_pcache.xInit method.
+*/
+static int pcache1Init(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  assert( pcache1.isInit==0 );
+  memset(&pcache1, 0, sizeof(pcache1));
+  if( sqlite3GlobalConfig.bCoreMutex ){
+    pcache1.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU);
+  }
+  pcache1.isInit = 1;
+  return SQLITE_OK;
+}
 
-        if( pPager->errCode ){
-          rc = pPager->errCode;
-          goto failed;
-        }
+/*
+** Implementation of the sqlite3_pcache.xShutdown method.
+** Note that the static mutex allocated in xInit does 
+** not need to be freed.
+*/
+static void pcache1Shutdown(void *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  assert( pcache1.isInit!=0 );
+  memset(&pcache1, 0, sizeof(pcache1));
+}
 
-        if( pPager->dbSize>0 ){
-          IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
-          rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers), 24);
-          if( rc!=SQLITE_OK ){
-            goto failed;
-          }
-        }else{
-          memset(dbFileVers, 0, sizeof(dbFileVers));
-        }
+/*
+** Implementation of the sqlite3_pcache.xCreate method.
+**
+** Allocate a new cache.
+*/
+static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
+  PCache1 *pCache;
 
-        if( memcmp(pPager->dbFileVers, dbFileVers, sizeof(dbFileVers))!=0 ){
-          pager_reset(pPager);
-        }
-      }
-    }
-    assert( pPager->exclusiveMode || pPager->state<=PAGER_SHARED );
-    if( pPager->state==PAGER_UNLOCK ){
-      pPager->state = PAGER_SHARED;
+  pCache = (PCache1 *)sqlite3_malloc(sizeof(PCache1));
+  if( pCache ){
+    memset(pCache, 0, sizeof(PCache1));
+    pCache->szPage = szPage;
+    pCache->bPurgeable = (bPurgeable ? 1 : 0);
+    if( bPurgeable ){
+      pCache->nMin = 10;
+      pcache1EnterMutex();
+      pcache1.nMinPage += pCache->nMin;
+      pcache1LeaveMutex();
     }
   }
+  return (sqlite3_pcache *)pCache;
+}
 
- failed:
-  if( rc!=SQLITE_OK ){
-    /* pager_unlock() is a no-op for exclusive mode and in-memory databases. */
-    pager_unlock(pPager);
+/*
+** Implementation of the sqlite3_pcache.xCachesize method. 
+**
+** Configure the cache_size limit for a cache.
+*/
+static void pcache1Cachesize(sqlite3_pcache *p, int nMax){
+  PCache1 *pCache = (PCache1 *)p;
+  if( pCache->bPurgeable ){
+    pcache1EnterMutex();
+    pcache1.nMaxPage += (nMax - pCache->nMax);
+    pCache->nMax = nMax;
+    pcache1EnforceMaxPage();
+    pcache1LeaveMutex();
   }
-  return rc;
 }
 
 /*
-** Allocate a PgHdr object.   Either create a new one or reuse
-** an existing one that is not otherwise in use.
+** Implementation of the sqlite3_pcache.xPagecount method. 
+*/
+static int pcache1Pagecount(sqlite3_pcache *p){
+  int n;
+  pcache1EnterMutex();
+  n = ((PCache1 *)p)->nPage;
+  pcache1LeaveMutex();
+  return n;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xFetch method. 
 **
-** A new PgHdr structure is created if any of the following are
-** true:
+** Fetch a page by key value.
 **
-**     (1)  We have not exceeded our maximum allocated cache size
-**          as set by the "PRAGMA cache_size" command.
+** Whether or not a new page may be allocated by this function depends on
+** the value of the createFlag argument.  0 means do not allocate a new
+** page.  1 means allocate a new page if space is easily available.  2 
+** means to try really hard to allocate a new page.
 **
-**     (2)  There are no unused PgHdr objects available at this time.
+** For a non-purgeable cache (a cache used as the storage for an in-memory
+** database) there is really no difference between createFlag 1 and 2.  So
+** the calling function (pcache.c) will never have a createFlag of 1 on
+** a non-purgable cache.
 **
-**     (3)  This is an in-memory database.
+** There are three different approaches to obtaining space for a page,
+** depending on the value of parameter createFlag (which may be 0, 1 or 2).
 **
-**     (4)  There are no PgHdr objects that do not require a journal
-**          file sync and a sync of the journal file is currently
-**          prohibited.
+**   1. Regardless of the value of createFlag, the cache is searched for a 
+**      copy of the requested page. If one is found, it is returned.
 **
-** Otherwise, reuse an existing PgHdr.  In other words, reuse an
-** existing PgHdr if all of the following are true:
+**   2. If createFlag==0 and the page is not already in the cache, NULL is
+**      returned.
 **
-**     (1)  We have reached or exceeded the maximum cache size
-**          allowed by "PRAGMA cache_size".
+**   3. If createFlag is 1, and the page is not already in the cache,
+**      and if either of the following are true, return NULL:
 **
-**     (2)  There is a PgHdr available with PgHdr->nRef==0
+**       (a) the number of pages pinned by the cache is greater than
+**           PCache1.nMax, or
+**       (b) the number of pages pinned by the cache is greater than
+**           the sum of nMax for all purgeable caches, less the sum of 
+**           nMin for all other purgeable caches. 
 **
-**     (3)  We are not in an in-memory database
+**   4. If none of the first three conditions apply and the cache is marked
+**      as purgeable, and if one of the following is true:
 **
-**     (4)  Either there is an available PgHdr that does not need
-**          to be synced to disk or else disk syncing is currently
-**          allowed.
+**       (a) The number of pages allocated for the cache is already 
+**           PCache1.nMax, or
+**
+**       (b) The number of pages allocated for all purgeable caches is
+**           already equal to or greater than the sum of nMax for all
+**           purgeable caches,
+**
+**      then attempt to recycle a page from the LRU list. If it is the right
+**      size, return the recycled buffer. Otherwise, free the buffer and
+**      proceed to step 5. 
+**
+**   5. Otherwise, allocate and return a new page buffer.
 */
-static int pagerAllocatePage(Pager *pPager, PgHdr **ppPg){
-  int rc = SQLITE_OK;
-  PgHdr *pPg;
-  int nByteHdr;
-
-  /* Create a new PgHdr if any of the four conditions defined 
-  ** above are met: */
-  if( pPager->nPage<pPager->mxPage
-   || pPager->lru.pFirst==0 
-   || MEMDB
-   || (pPager->lru.pFirstSynced==0 && pPager->doNotSync)
-  ){
-    void *pData;
-    if( pPager->nPage>=pPager->nHash ){
-      pager_resize_hash_table(pPager,
-         pPager->nHash<256 ? 256 : pPager->nHash*2);
-      if( pPager->nHash==0 ){
-        rc = SQLITE_NOMEM;
-        goto pager_allocate_out;
-      }
-    }
-    pagerLeave(pPager);
-    nByteHdr = sizeof(*pPg) + sizeof(u32) + pPager->nExtra
-              + MEMDB*sizeof(PgHistory);
-    pPg = sqlite3_malloc( nByteHdr );
-    if( pPg ){
-      pData = sqlite3_malloc( pPager->pageSize );
-      if( pData==0 ){
-        sqlite3_free(pPg);
-        pPg = 0;
-      }
-    }
-    pagerEnter(pPager);
-    if( pPg==0 ){
-      rc = SQLITE_NOMEM;
-      goto pager_allocate_out;
-    }
-    memset(pPg, 0, nByteHdr);
-    pPg->pData = pData;
-    pPg->pPager = pPager;
-    pPg->pNextAll = pPager->pAll;
-    pPager->pAll = pPg;
-    pPager->nPage++;
-  }else{
-    /* Recycle an existing page with a zero ref-count. */
-    rc = pager_recycle(pPager, &pPg);
-    if( rc==SQLITE_BUSY ){
-      rc = SQLITE_IOERR_BLOCKED;
-    }
-    if( rc!=SQLITE_OK ){
-      goto pager_allocate_out;
+static void *pcache1Fetch(sqlite3_pcache *p, unsigned int iKey, int createFlag){
+  unsigned int nPinned;
+  PCache1 *pCache = (PCache1 *)p;
+  PgHdr1 *pPage = 0;
+
+  assert( pCache->bPurgeable || createFlag!=1 );
+  pcache1EnterMutex();
+  if( createFlag==1 ) sqlite3BeginBenignMalloc();
+
+  /* Search the hash table for an existing entry. */
+  if( pCache->nHash>0 ){
+    unsigned int h = iKey % pCache->nHash;
+    for(pPage=pCache->apHash[h]; pPage&&pPage->iKey!=iKey; pPage=pPage->pNext);
+  }
+
+  if( pPage || createFlag==0 ){
+    pcache1PinPage(pPage);
+    goto fetch_out;
+  }
+
+  /* Step 3 of header comment. */
+  nPinned = pCache->nPage - pCache->nRecyclable;
+  if( createFlag==1 && (
+        nPinned>=(pcache1.nMaxPage+pCache->nMin-pcache1.nMinPage)
+     || nPinned>=(pCache->nMax * 9 / 10)
+  )){
+    goto fetch_out;
+  }
+
+  if( pCache->nPage>=pCache->nHash && pcache1ResizeHash(pCache) ){
+    goto fetch_out;
+  }
+
+  /* Step 4. Try to recycle a page buffer if appropriate. */
+  if( pCache->bPurgeable && pcache1.pLruTail && (
+     (pCache->nPage+1>=pCache->nMax) || pcache1.nCurrentPage>=pcache1.nMaxPage
+  )){
+    pPage = pcache1.pLruTail;
+    pcache1RemoveFromHash(pPage);
+    pcache1PinPage(pPage);
+    if( pPage->pCache->szPage!=pCache->szPage ){
+      pcache1FreePage(pPage);
+      pPage = 0;
+    }else{
+      pcache1.nCurrentPage -= (pPage->pCache->bPurgeable - pCache->bPurgeable);
     }
-    assert( pPager->state>=SHARED_LOCK );
-    assert(pPg);
   }
-  *ppPg = pPg;
 
-pager_allocate_out:
-  return rc;
+  /* Step 5. If a usable page buffer has still not been found, 
+  ** attempt to allocate a new one. 
+  */
+  if( !pPage ){
+    pPage = pcache1AllocPage(pCache);
+  }
+
+  if( pPage ){
+    unsigned int h = iKey % pCache->nHash;
+    pCache->nPage++;
+    pPage->iKey = iKey;
+    pPage->pNext = pCache->apHash[h];
+    pPage->pCache = pCache;
+    pPage->pLruPrev = 0;
+    pPage->pLruNext = 0;
+    *(void **)(PGHDR1_TO_PAGE(pPage)) = 0;
+    pCache->apHash[h] = pPage;
+  }
+
+fetch_out:
+  if( pPage && iKey>pCache->iMaxKey ){
+    pCache->iMaxKey = iKey;
+  }
+  if( createFlag==1 ) sqlite3EndBenignMalloc();
+  pcache1LeaveMutex();
+  return (pPage ? PGHDR1_TO_PAGE(pPage) : 0);
 }
 
+
 /*
-** Make sure we have the content for a page.  If the page was
-** previously acquired with noContent==1, then the content was
-** just initialized to zeros instead of being read from disk.
-** But now we need the real data off of disk.  So make sure we
-** have it.  Read it in if we do not have it already.
+** Implementation of the sqlite3_pcache.xUnpin method.
+**
+** Mark a page as unpinned (eligible for asynchronous recycling).
 */
-static int pager_get_content(PgHdr *pPg){
-  if( pPg->needRead ){
-    int rc = readDbPage(pPg->pPager, pPg, pPg->pgno);
-    if( rc==SQLITE_OK ){
-      pPg->needRead = 0;
+static void pcache1Unpin(sqlite3_pcache *p, void *pPg, int reuseUnlikely){
+  PCache1 *pCache = (PCache1 *)p;
+  PgHdr1 *pPage = PAGE_TO_PGHDR1(pCache, pPg);
+ 
+  assert( pPage->pCache==pCache );
+  pcache1EnterMutex();
+
+  /* It is an error to call this function if the page is already 
+  ** part of the global LRU list.
+  */
+  assert( pPage->pLruPrev==0 && pPage->pLruNext==0 );
+  assert( pcache1.pLruHead!=pPage && pcache1.pLruTail!=pPage );
+
+  if( reuseUnlikely || pcache1.nCurrentPage>pcache1.nMaxPage ){
+    pcache1RemoveFromHash(pPage);
+    pcache1FreePage(pPage);
+  }else{
+    /* Add the page to the global LRU list. Normally, the page is added to
+    ** the head of the list (last page to be recycled). However, if the 
+    ** reuseUnlikely flag passed to this function is true, the page is added
+    ** to the tail of the list (first page to be recycled).
+    */
+    if( pcache1.pLruHead ){
+      pcache1.pLruHead->pLruPrev = pPage;
+      pPage->pLruNext = pcache1.pLruHead;
+      pcache1.pLruHead = pPage;
     }else{
-      return rc;
+      pcache1.pLruTail = pPage;
+      pcache1.pLruHead = pPage;
     }
+    pCache->nRecyclable++;
   }
-  return SQLITE_OK;
+
+  pcache1LeaveMutex();
 }
 
 /*
-** Acquire a page.
-**
-** A read lock on the disk file is obtained when the first page is acquired. 
-** This read lock is dropped when the last page is released.
-**
-** This routine works for any page number greater than 0.  If the database
-** file is smaller than the requested page, then no actual disk
-** read occurs and the memory image of the page is initialized to
-** all zeros.  The extra data appended to a page is always initialized
-** to zeros the first time a page is loaded into memory.
-**
-** The acquisition might fail for several reasons.  In all cases,
-** an appropriate error code is returned and *ppPage is set to NULL.
-**
-** See also sqlite3PagerLookup().  Both this routine and Lookup() attempt
-** to find a page in the in-memory cache first.  If the page is not already
-** in memory, this routine goes to disk to read it in whereas Lookup()
-** just returns 0.  This routine acquires a read-lock the first time it
-** has to go to disk, and could also playback an old journal if necessary.
-** Since Lookup() never goes to disk, it never has to deal with locks
-** or journal files.
-**
-** If noContent is false, the page contents are actually read from disk.
-** If noContent is true, it means that we do not care about the contents
-** of the page at this time, so do not do a disk read.  Just fill in the
-** page content with zeros.  But mark the fact that we have not read the
-** content by setting the PgHdr.needRead flag.  Later on, if 
-** sqlite3PagerWrite() is called on this page or if this routine is
-** called again with noContent==0, that means that the content is needed
-** and the disk read should occur at that point.
-*/
-static int pagerAcquire(
-  Pager *pPager,      /* The pager open on the database file */
-  Pgno pgno,          /* Page number to fetch */
-  DbPage **ppPage,    /* Write a pointer to the page here */
-  int noContent       /* Do not bother reading content from disk if true */
+** Implementation of the sqlite3_pcache.xRekey method. 
+*/
+static void pcache1Rekey(
+  sqlite3_pcache *p,
+  void *pPg,
+  unsigned int iOld,
+  unsigned int iNew
 ){
-  PgHdr *pPg;
-  int rc;
+  PCache1 *pCache = (PCache1 *)p;
+  PgHdr1 *pPage = PAGE_TO_PGHDR1(pCache, pPg);
+  PgHdr1 **pp;
+  unsigned int h; 
+  assert( pPage->iKey==iOld );
+  assert( pPage->pCache==pCache );
 
-  assert( pPager->state==PAGER_UNLOCK || pPager->nRef>0 || pgno==1 );
+  pcache1EnterMutex();
 
-  /* The maximum page number is 2^31. Return SQLITE_CORRUPT if a page
-  ** number greater than this, or zero, is requested.
-  */
-  if( pgno>PAGER_MAX_PGNO || pgno==0 || pgno==PAGER_MJ_PGNO(pPager) ){
-    return SQLITE_CORRUPT_BKPT;
+  h = iOld%pCache->nHash;
+  pp = &pCache->apHash[h];
+  while( (*pp)!=pPage ){
+    pp = &(*pp)->pNext;
   }
+  *pp = pPage->pNext;
 
-  /* Make sure we have not hit any critical errors.
-  */ 
-  assert( pPager!=0 );
-  *ppPage = 0;
+  h = iNew%pCache->nHash;
+  pPage->iKey = iNew;
+  pPage->pNext = pCache->apHash[h];
+  pCache->apHash[h] = pPage;
 
-  /* If this is the first page accessed, then get a SHARED lock
-  ** on the database file. pagerSharedLock() is a no-op if 
-  ** a database lock is already held.
+  /* The xRekey() interface is only used to move pages earlier in the
+  ** database file (in order to move all free pages to the end of the
+  ** file where they can be truncated off.)  Hence, it is not possible
+  ** for the new page number to be greater than the largest previously
+  ** fetched page.  But we retain the following test in case xRekey()
+  ** begins to be used in different ways in the future.
   */
-  rc = pagerSharedLock(pPager);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  if( NEVER(iNew>pCache->iMaxKey) ){
+    pCache->iMaxKey = iNew;
   }
-  assert( pPager->state!=PAGER_UNLOCK );
-
-  pPg = pager_lookup(pPager, pgno);
-  if( pPg==0 ){
-    /* The requested page is not in the page cache. */
-    int nMax;
-    int h;
-    PAGER_INCR(pPager->nMiss);
-    rc = pagerAllocatePage(pPager, &pPg);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-
-    pPg->pgno = pgno;
-    assert( !MEMDB || pgno>pPager->stmtSize );
-    pPg->inJournal = sqlite3BitvecTest(pPager->pInJournal, pgno);
-    pPg->needSync = 0;
-
-    makeClean(pPg);
-    pPg->nRef = 1;
-
-    pPager->nRef++;
-    if( pPager->nExtra>0 ){
-      memset(PGHDR_TO_EXTRA(pPg, pPager), 0, pPager->nExtra);
-    }
-    nMax = sqlite3PagerPagecount(pPager);
-    if( pPager->errCode ){
-      rc = pPager->errCode;
-      sqlite3PagerUnref(pPg);
-      return rc;
-    }
-
-    /* Populate the page with data, either by reading from the database
-    ** file, or by setting the entire page to zero.
-    */
-    if( nMax<(int)pgno || MEMDB || (noContent && !pPager->alwaysRollback) ){
-      if( pgno>pPager->mxPgno ){
-        sqlite3PagerUnref(pPg);
-        return SQLITE_FULL;
-      }
-      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
-      pPg->needRead = noContent && !pPager->alwaysRollback;
-      IOTRACE(("ZERO %p %d\n", pPager, pgno));
-    }else{
-      rc = readDbPage(pPager, pPg, pgno);
-      if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
-        pPg->pgno = 0;
-        sqlite3PagerUnref(pPg);
-        return rc;
-      }
-      pPg->needRead = 0;
-    }
 
-    /* Link the page into the page hash table */
-    h = pgno & (pPager->nHash-1);
-    assert( pgno!=0 );
-    pPg->pNextHash = pPager->aHash[h];
-    pPager->aHash[h] = pPg;
-    if( pPg->pNextHash ){
-      assert( pPg->pNextHash->pPrevHash==0 );
-      pPg->pNextHash->pPrevHash = pPg;
-    }
+  pcache1LeaveMutex();
+}
 
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
-  }else{
-    /* The requested page is in the page cache. */
-    assert(pPager->nRef>0 || pgno==1);
-    PAGER_INCR(pPager->nHit);
-    if( !noContent ){
-      rc = pager_get_content(pPg);
-      if( rc ){
-        return rc;
-      }
-    }
-    page_ref(pPg);
+/*
+** Implementation of the sqlite3_pcache.xTruncate method. 
+**
+** Discard all unpinned pages in the cache with a page number equal to
+** or greater than parameter iLimit. Any pinned pages with a page number
+** equal to or greater than iLimit are implicitly unpinned.
+*/
+static void pcache1Truncate(sqlite3_pcache *p, unsigned int iLimit){
+  PCache1 *pCache = (PCache1 *)p;
+  pcache1EnterMutex();
+  if( iLimit<=pCache->iMaxKey ){
+    pcache1TruncateUnsafe(pCache, iLimit);
+    pCache->iMaxKey = iLimit-1;
   }
-  *ppPage = pPg;
-  return SQLITE_OK;
+  pcache1LeaveMutex();
 }
-SQLITE_PRIVATE int sqlite3PagerAcquire(
-  Pager *pPager,      /* The pager open on the database file */
-  Pgno pgno,          /* Page number to fetch */
-  DbPage **ppPage,    /* Write a pointer to the page here */
-  int noContent       /* Do not bother reading content from disk if true */
-){
-  int rc;
-  pagerEnter(pPager);
-  rc = pagerAcquire(pPager, pgno, ppPage, noContent);
-  pagerLeave(pPager);
-  return rc;
+
+/*
+** Implementation of the sqlite3_pcache.xDestroy method. 
+**
+** Destroy a cache allocated using pcache1Create().
+*/
+static void pcache1Destroy(sqlite3_pcache *p){
+  PCache1 *pCache = (PCache1 *)p;
+  pcache1EnterMutex();
+  pcache1TruncateUnsafe(pCache, 0);
+  pcache1.nMaxPage -= pCache->nMax;
+  pcache1.nMinPage -= pCache->nMin;
+  pcache1EnforceMaxPage();
+  pcache1LeaveMutex();
+  sqlite3_free(pCache->apHash);
+  sqlite3_free(pCache);
 }
 
+/*
+** This function is called during initialization (sqlite3_initialize()) to
+** install the default pluggable cache module, assuming the user has not
+** already provided an alternative.
+*/
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void){
+  static sqlite3_pcache_methods defaultMethods = {
+    0,                       /* pArg */
+    pcache1Init,             /* xInit */
+    pcache1Shutdown,         /* xShutdown */
+    pcache1Create,           /* xCreate */
+    pcache1Cachesize,        /* xCachesize */
+    pcache1Pagecount,        /* xPagecount */
+    pcache1Fetch,            /* xFetch */
+    pcache1Unpin,            /* xUnpin */
+    pcache1Rekey,            /* xRekey */
+    pcache1Truncate,         /* xTruncate */
+    pcache1Destroy           /* xDestroy */
+  };
+  sqlite3_config(SQLITE_CONFIG_PCACHE, &defaultMethods);
+}
 
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
 /*
-** Acquire a page if it is already in the in-memory cache.  Do
-** not read the page from disk.  Return a pointer to the page,
-** or 0 if the page is not in cache.
+** This function is called to free superfluous dynamically allocated memory
+** held by the pager system. Memory in use by any SQLite pager allocated
+** by the current thread may be sqlite3_free()ed.
 **
-** See also sqlite3PagerGet().  The difference between this routine
-** and sqlite3PagerGet() is that _get() will go to the disk and read
-** in the page if the page is not already in cache.  This routine
-** returns NULL if the page is not in cache or if a disk I/O error 
-** has ever happened.
+** nReq is the number of bytes of memory required. Once this much has
+** been released, the function returns. The return value is the total number 
+** of bytes of memory released.
 */
-SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
-  PgHdr *pPg = 0;
-
-  assert( pPager!=0 );
-  assert( pgno!=0 );
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int nReq){
+  int nFree = 0;
+  if( pcache1.pStart==0 ){
+    PgHdr1 *p;
+    pcache1EnterMutex();
+    while( (nReq<0 || nFree<nReq) && (p=pcache1.pLruTail) ){
+      nFree += sqlite3MallocSize(PGHDR1_TO_PAGE(p));
+      pcache1PinPage(p);
+      pcache1RemoveFromHash(p);
+      pcache1FreePage(p);
+    }
+    pcache1LeaveMutex();
+  }
+  return nFree;
+}
+#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
 
-  pagerEnter(pPager);
-  if( pPager->state==PAGER_UNLOCK ){
-    assert( !pPager->pAll || pPager->exclusiveMode );
-  }else if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
-    /* Do nothing */
-  }else if( (pPg = pager_lookup(pPager, pgno))!=0 ){
-    page_ref(pPg);
+#ifdef SQLITE_TEST
+/*
+** This function is used by test procedures to inspect the internal state
+** of the global cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheStats(
+  int *pnCurrent,      /* OUT: Total number of pages cached */
+  int *pnMax,          /* OUT: Global maximum cache size */
+  int *pnMin,          /* OUT: Sum of PCache1.nMin for purgeable caches */
+  int *pnRecyclable    /* OUT: Total number of pages available for recycling */
+){
+  PgHdr1 *p;
+  int nRecyclable = 0;
+  for(p=pcache1.pLruHead; p; p=p->pLruNext){
+    nRecyclable++;
   }
-  pagerLeave(pPager);
-  return pPg;
+  *pnCurrent = pcache1.nCurrentPage;
+  *pnMax = pcache1.nMaxPage;
+  *pnMin = pcache1.nMinPage;
+  *pnRecyclable = nRecyclable;
 }
+#endif
 
+/************** End of pcache1.c *********************************************/
+/************** Begin file rowset.c ******************************************/
 /*
-** Release a page.
+** 2008 December 3
 **
-** If the number of references to the page drop to zero, then the
-** page is added to the LRU list.  When all references to all pages
-** are released, a rollback occurs and the lock on the database is
-** removed.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This module implements an object we call a "RowSet".
+**
+** The RowSet object is a collection of rowids.  Rowids
+** are inserted into the RowSet in an arbitrary order.  Inserts
+** can be intermixed with tests to see if a given rowid has been
+** previously inserted into the RowSet.
+**
+** After all inserts are finished, it is possible to extract the
+** elements of the RowSet in sorted order.  Once this extraction
+** process has started, no new elements may be inserted.
+**
+** Hence, the primitive operations for a RowSet are:
+**
+**    CREATE
+**    INSERT
+**    TEST
+**    SMALLEST
+**    DESTROY
+**
+** The CREATE and DESTROY primitives are the constructor and destructor,
+** obviously.  The INSERT primitive adds a new element to the RowSet.
+** TEST checks to see if an element is already in the RowSet.  SMALLEST
+** extracts the least value from the RowSet.
+**
+** The INSERT primitive might allocate additional memory.  Memory is
+** allocated in chunks so most INSERTs do no allocation.  There is an 
+** upper bound on the size of allocated memory.  No memory is freed
+** until DESTROY.
+**
+** The TEST primitive includes a "batch" number.  The TEST primitive
+** will only see elements that were inserted before the last change
+** in the batch number.  In other words, if an INSERT occurs between
+** two TESTs where the TESTs have the same batch nubmer, then the
+** value added by the INSERT will not be visible to the second TEST.
+** The initial batch number is zero, so if the very first TEST contains
+** a non-zero batch number, it will see all prior INSERTs.
+**
+** No INSERTs may occurs after a SMALLEST.  An assertion will fail if
+** that is attempted.
+**
+** The cost of an INSERT is roughly constant.  (Sometime new memory
+** has to be allocated on an INSERT.)  The cost of a TEST with a new
+** batch number is O(NlogN) where N is the number of elements in the RowSet.
+** The cost of a TEST using the same batch number is O(logN).  The cost
+** of the first SMALLEST is O(NlogN).  Second and subsequent SMALLEST
+** primitives are constant time.  The cost of DESTROY is O(N).
+**
+** There is an added cost of O(N) when switching between TEST and
+** SMALLEST primitives.
+**
+** $Id: rowset.c,v 1.7 2009/05/22 01:00:13 drh Exp $
 */
-SQLITE_PRIVATE int sqlite3PagerUnref(DbPage *pPg){
-  Pager *pPager;
 
-  if( pPg==0 ) return SQLITE_OK;
-  pPager = pPg->pPager;
 
-  /* Decrement the reference count for this page
-  */
-  assert( pPg->nRef>0 );
-  pagerEnter(pPg->pPager);
-  pPg->nRef--;
+/*
+** Target size for allocation chunks.
+*/
+#define ROWSET_ALLOCATION_SIZE 1024
 
-  CHECK_PAGE(pPg);
+/*
+** The number of rowset entries per allocation chunk.
+*/
+#define ROWSET_ENTRY_PER_CHUNK  \
+                       ((ROWSET_ALLOCATION_SIZE-8)/sizeof(struct RowSetEntry))
 
-  /* When the number of references to a page reach 0, call the
-  ** destructor and add the page to the freelist.
-  */
-  if( pPg->nRef==0 ){
+/*
+** Each entry in a RowSet is an instance of the following object.
+*/
+struct RowSetEntry {            
+  i64 v;                        /* ROWID value for this entry */
+  struct RowSetEntry *pRight;   /* Right subtree (larger entries) or list */
+  struct RowSetEntry *pLeft;    /* Left subtree (smaller entries) */
+};
 
-    lruListAdd(pPg);
-    if( pPager->xDestructor ){
-      pPager->xDestructor(pPg, pPager->pageSize);
-    }
-  
-    /* When all pages reach the freelist, drop the read lock from
-    ** the database file.
-    */
-    pPager->nRef--;
-    assert( pPager->nRef>=0 );
-    if( pPager->nRef==0 && (!pPager->exclusiveMode || pPager->journalOff>0) ){
-      pagerUnlockAndRollback(pPager);
-    }
-  }
-  pagerLeave(pPager);
-  return SQLITE_OK;
-}
+/*
+** RowSetEntry objects are allocated in large chunks (instances of the
+** following structure) to reduce memory allocation overhead.  The
+** chunks are kept on a linked list so that they can be deallocated
+** when the RowSet is destroyed.
+*/
+struct RowSetChunk {
+  struct RowSetChunk *pNextChunk;        /* Next chunk on list of them all */
+  struct RowSetEntry aEntry[ROWSET_ENTRY_PER_CHUNK]; /* Allocated entries */
+};
 
 /*
-** Create a journal file for pPager.  There should already be a RESERVED
-** or EXCLUSIVE lock on the database file when this routine is called.
+** A RowSet in an instance of the following structure.
 **
-** Return SQLITE_OK if everything.  Return an error code and release the
-** write lock if anything goes wrong.
+** A typedef of this structure if found in sqliteInt.h.
 */
-static int pager_open_journal(Pager *pPager){
-  sqlite3_vfs *pVfs = pPager->pVfs;
-  int flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_CREATE);
+struct RowSet {
+  struct RowSetChunk *pChunk;    /* List of all chunk allocations */
+  sqlite3 *db;                   /* The database connection */
+  struct RowSetEntry *pEntry;    /* List of entries using pRight */
+  struct RowSetEntry *pLast;     /* Last entry on the pEntry list */
+  struct RowSetEntry *pFresh;    /* Source of new entry objects */
+  struct RowSetEntry *pTree;     /* Binary tree of entries */
+  u16 nFresh;                    /* Number of objects on pFresh */
+  u8 isSorted;                   /* True if pEntry is sorted */
+  u8 iBatch;                     /* Current insert batch */
+};
 
-  int rc;
-  assert( !MEMDB );
-  assert( pPager->state>=PAGER_RESERVED );
-  assert( pPager->useJournal );
-  assert( pPager->pInJournal==0 );
-  sqlite3PagerPagecount(pPager);
-  pagerLeave(pPager);
-  pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
-  pagerEnter(pPager);
-  if( pPager->pInJournal==0 ){
-    rc = SQLITE_NOMEM;
-    goto failed_to_open_journal;
-  }
+/*
+** Turn bulk memory into a RowSet object.  N bytes of memory
+** are available at pSpace.  The db pointer is used as a memory context
+** for any subsequent allocations that need to occur.
+** Return a pointer to the new RowSet object.
+**
+** It must be the case that N is sufficient to make a Rowset.  If not
+** an assertion fault occurs.
+** 
+** If N is larger than the minimum, use the surplus as an initial
+** allocation of entries available to be filled.
+*/
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3 *db, void *pSpace, unsigned int N){
+  RowSet *p;
+  assert( N >= ROUND8(sizeof(*p)) );
+  p = pSpace;
+  p->pChunk = 0;
+  p->db = db;
+  p->pEntry = 0;
+  p->pLast = 0;
+  p->pTree = 0;
+  p->pFresh = (struct RowSetEntry*)(ROUND8(sizeof(*p)) + (char*)p);
+  p->nFresh = (u16)((N - ROUND8(sizeof(*p)))/sizeof(struct RowSetEntry));
+  p->isSorted = 1;
+  p->iBatch = 0;
+  return p;
+}
 
-  if( pPager->journalOpen==0 ){
-    if( pPager->tempFile ){
-      flags |= (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL);
-    }else{
-      flags |= (SQLITE_OPEN_MAIN_JOURNAL);
-    }
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-    rc = sqlite3JournalOpen(
-        pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
-    );
-#else
-    rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
-#endif
-    assert( rc!=SQLITE_OK || pPager->jfd->pMethods );
-    pPager->journalOff = 0;
-    pPager->setMaster = 0;
-    pPager->journalHdr = 0;
-    if( rc!=SQLITE_OK ){
-      if( rc==SQLITE_NOMEM ){
-        sqlite3OsDelete(pVfs, pPager->zJournal, 0);
-      }
-      goto failed_to_open_journal;
-    }
-  }
-  pPager->journalOpen = 1;
-  pPager->journalStarted = 0;
-  pPager->needSync = 0;
-  pPager->alwaysRollback = 0;
-  pPager->nRec = 0;
-  if( pPager->errCode ){
-    rc = pPager->errCode;
-    goto failed_to_open_journal;
+/*
+** Deallocate all chunks from a RowSet.  This frees all memory that
+** the RowSet has allocated over its lifetime.  This routine is
+** the destructor for the RowSet.
+*/
+SQLITE_PRIVATE void sqlite3RowSetClear(RowSet *p){
+  struct RowSetChunk *pChunk, *pNextChunk;
+  for(pChunk=p->pChunk; pChunk; pChunk = pNextChunk){
+    pNextChunk = pChunk->pNextChunk;
+    sqlite3DbFree(p->db, pChunk);
   }
-  pPager->origDbSize = pPager->dbSize;
-
-  rc = writeJournalHdr(pPager);
+  p->pChunk = 0;
+  p->nFresh = 0;
+  p->pEntry = 0;
+  p->pLast = 0;
+  p->pTree = 0;
+  p->isSorted = 1;
+}
 
-  if( pPager->stmtAutoopen && rc==SQLITE_OK ){
-    rc = sqlite3PagerStmtBegin(pPager);
-  }
-  if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM && rc!=SQLITE_IOERR_NOMEM ){
-    rc = pager_end_transaction(pPager, 0);
-    if( rc==SQLITE_OK ){
-      rc = SQLITE_FULL;
+/*
+** Insert a new value into a RowSet.
+**
+** The mallocFailed flag of the database connection is set if a
+** memory allocation fails.
+*/
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet *p, i64 rowid){
+  struct RowSetEntry *pEntry;  /* The new entry */
+  struct RowSetEntry *pLast;   /* The last prior entry */
+  assert( p!=0 );
+  if( p->nFresh==0 ){
+    struct RowSetChunk *pNew;
+    pNew = sqlite3DbMallocRaw(p->db, sizeof(*pNew));
+    if( pNew==0 ){
+      return;
     }
+    pNew->pNextChunk = p->pChunk;
+    p->pChunk = pNew;
+    p->pFresh = pNew->aEntry;
+    p->nFresh = ROWSET_ENTRY_PER_CHUNK;
+  }
+  pEntry = p->pFresh++;
+  p->nFresh--;
+  pEntry->v = rowid;
+  pEntry->pRight = 0;
+  pLast = p->pLast;
+  if( pLast ){
+    if( p->isSorted && rowid<=pLast->v ){
+      p->isSorted = 0;
+    }
+    pLast->pRight = pEntry;
+  }else{
+    assert( p->pEntry==0 ); /* Fires if INSERT after SMALLEST */
+    p->pEntry = pEntry;
   }
-  return rc;
-
-failed_to_open_journal:
-  sqlite3BitvecDestroy(pPager->pInJournal);
-  pPager->pInJournal = 0;
-  return rc;
+  p->pLast = pEntry;
 }
 
 /*
-** Acquire a write-lock on the database.  The lock is removed when
-** the any of the following happen:
-**
-**   *  sqlite3PagerCommitPhaseTwo() is called.
-**   *  sqlite3PagerRollback() is called.
-**   *  sqlite3PagerClose() is called.
-**   *  sqlite3PagerUnref() is called to on every outstanding page.
-**
-** The first parameter to this routine is a pointer to any open page of the
-** database file.  Nothing changes about the page - it is used merely to
-** acquire a pointer to the Pager structure and as proof that there is
-** already a read-lock on the database.
-**
-** The second parameter indicates how much space in bytes to reserve for a
-** master journal file-name at the start of the journal when it is created.
-**
-** A journal file is opened if this is not a temporary file.  For temporary
-** files, the opening of the journal file is deferred until there is an
-** actual need to write to the journal.
+** Merge two lists of RowSetEntry objects.  Remove duplicates.
 **
-** If the database is already reserved for writing, this routine is a no-op.
-**
-** If exFlag is true, go ahead and get an EXCLUSIVE lock on the file
-** immediately instead of waiting until we try to flush the cache.  The
-** exFlag is ignored if a transaction is already active.
+** The input lists are connected via pRight pointers and are 
+** assumed to each already be in sorted order.
 */
-SQLITE_PRIVATE int sqlite3PagerBegin(DbPage *pPg, int exFlag){
-  Pager *pPager = pPg->pPager;
-  int rc = SQLITE_OK;
-  pagerEnter(pPager);
-  assert( pPg->nRef>0 );
-  assert( pPager->state!=PAGER_UNLOCK );
-  if( pPager->state==PAGER_SHARED ){
-    assert( pPager->pInJournal==0 );
-    if( MEMDB ){
-      pPager->state = PAGER_EXCLUSIVE;
-      pPager->origDbSize = pPager->dbSize;
-    }else{
-      rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
-      if( rc==SQLITE_OK ){
-        pPager->state = PAGER_RESERVED;
-        if( exFlag ){
-          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
-        }
-      }
-      if( rc!=SQLITE_OK ){
-        pagerLeave(pPager);
-        return rc;
-      }
-      pPager->dirtyCache = 0;
-      PAGERTRACE2("TRANSACTION %d\n", PAGERID(pPager));
-      if( pPager->useJournal && !pPager->tempFile
-             && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
-        rc = pager_open_journal(pPager);
-      }
-    }
-  }else if( pPager->journalOpen && pPager->journalOff==0 ){
-    /* This happens when the pager was in exclusive-access mode the last
-    ** time a (read or write) transaction was successfully concluded
-    ** by this connection. Instead of deleting the journal file it was 
-    ** kept open and either was truncated to 0 bytes or its header was
-    ** overwritten with zeros.
-    */
-    assert( pPager->nRec==0 );
-    assert( pPager->origDbSize==0 );
-    assert( pPager->pInJournal==0 );
-    sqlite3PagerPagecount(pPager);
-    pagerLeave(pPager);
-    pPager->pInJournal = sqlite3BitvecCreate( pPager->dbSize );
-    pagerEnter(pPager);
-    if( !pPager->pInJournal ){
-      rc = SQLITE_NOMEM;
+static struct RowSetEntry *rowSetMerge(
+  struct RowSetEntry *pA,    /* First sorted list to be merged */
+  struct RowSetEntry *pB     /* Second sorted list to be merged */
+){
+  struct RowSetEntry head;
+  struct RowSetEntry *pTail;
+
+  pTail = &head;
+  while( pA && pB ){
+    assert( pA->pRight==0 || pA->v<=pA->pRight->v );
+    assert( pB->pRight==0 || pB->v<=pB->pRight->v );
+    if( pA->v<pB->v ){
+      pTail->pRight = pA;
+      pA = pA->pRight;
+      pTail = pTail->pRight;
+    }else if( pB->v<pA->v ){
+      pTail->pRight = pB;
+      pB = pB->pRight;
+      pTail = pTail->pRight;
     }else{
-      pPager->origDbSize = pPager->dbSize;
-      rc = writeJournalHdr(pPager);
+      pA = pA->pRight;
     }
   }
-  assert( !pPager->journalOpen || pPager->journalOff>0 || rc!=SQLITE_OK );
-  pagerLeave(pPager);
-  return rc;
+  if( pA ){
+    assert( pA->pRight==0 || pA->v<=pA->pRight->v );
+    pTail->pRight = pA;
+  }else{
+    assert( pB==0 || pB->pRight==0 || pB->v<=pB->pRight->v );
+    pTail->pRight = pB;
+  }
+  return head.pRight;
 }
 
 /*
-** Make a page dirty.  Set its dirty flag and add it to the dirty
-** page list.
-*/
-static void makeDirty(PgHdr *pPg){
-  if( pPg->dirty==0 ){
-    Pager *pPager = pPg->pPager;
-    pPg->dirty = 1;
-    pPg->pDirty = pPager->pDirty;
-    if( pPager->pDirty ){
-      pPager->pDirty->pPrevDirty = pPg;
+** Sort all elements on the pEntry list of the RowSet into ascending order.
+*/ 
+static void rowSetSort(RowSet *p){
+  unsigned int i;
+  struct RowSetEntry *pEntry;
+  struct RowSetEntry *aBucket[40];
+
+  assert( p->isSorted==0 );
+  memset(aBucket, 0, sizeof(aBucket));
+  while( p->pEntry ){
+    pEntry = p->pEntry;
+    p->pEntry = pEntry->pRight;
+    pEntry->pRight = 0;
+    for(i=0; aBucket[i]; i++){
+      pEntry = rowSetMerge(aBucket[i], pEntry);
+      aBucket[i] = 0;
     }
-    pPg->pPrevDirty = 0;
-    pPager->pDirty = pPg;
+    aBucket[i] = pEntry;
+  }
+  pEntry = 0;
+  for(i=0; i<sizeof(aBucket)/sizeof(aBucket[0]); i++){
+    pEntry = rowSetMerge(pEntry, aBucket[i]);
   }
+  p->pEntry = pEntry;
+  p->pLast = 0;
+  p->isSorted = 1;
 }
 
+
 /*
-** Make a page clean.  Clear its dirty bit and remove it from the
-** dirty page list.
+** The input, pIn, is a binary tree (or subtree) of RowSetEntry objects.
+** Convert this tree into a linked list connected by the pRight pointers
+** and return pointers to the first and last elements of the new list.
 */
-static void makeClean(PgHdr *pPg){
-  if( pPg->dirty ){
-    pPg->dirty = 0;
-    if( pPg->pDirty ){
-      assert( pPg->pDirty->pPrevDirty==pPg );
-      pPg->pDirty->pPrevDirty = pPg->pPrevDirty;
-    }
-    if( pPg->pPrevDirty ){
-      assert( pPg->pPrevDirty->pDirty==pPg );
-      pPg->pPrevDirty->pDirty = pPg->pDirty;
-    }else{
-      assert( pPg->pPager->pDirty==pPg );
-      pPg->pPager->pDirty = pPg->pDirty;
-    }
+static void rowSetTreeToList(
+  struct RowSetEntry *pIn,         /* Root of the input tree */
+  struct RowSetEntry **ppFirst,    /* Write head of the output list here */
+  struct RowSetEntry **ppLast      /* Write tail of the output list here */
+){
+  assert( pIn!=0 );
+  if( pIn->pLeft ){
+    struct RowSetEntry *p;
+    rowSetTreeToList(pIn->pLeft, ppFirst, &p);
+    p->pRight = pIn;
+  }else{
+    *ppFirst = pIn;
   }
+  if( pIn->pRight ){
+    rowSetTreeToList(pIn->pRight, &pIn->pRight, ppLast);
+  }else{
+    *ppLast = pIn;
+  }
+  assert( (*ppLast)->pRight==0 );
 }
 
 
 /*
-** Mark a data page as writeable.  The page is written into the journal 
-** if it is not there already.  This routine must be called before making
-** changes to a page.
+** Convert a sorted list of elements (connected by pRight) into a binary
+** tree with depth of iDepth.  A depth of 1 means the tree contains a single
+** node taken from the head of *ppList.  A depth of 2 means a tree with
+** three nodes.  And so forth.
 **
-** The first time this routine is called, the pager creates a new
-** journal and acquires a RESERVED lock on the database.  If the RESERVED
-** lock could not be acquired, this routine returns SQLITE_BUSY.  The
-** calling routine must check for that return value and be careful not to
-** change any page data until this routine returns SQLITE_OK.
+** Use as many entries from the input list as required and update the
+** *ppList to point to the unused elements of the list.  If the input
+** list contains too few elements, then construct an incomplete tree
+** and leave *ppList set to NULL.
 **
-** If the journal file could not be written because the disk is full,
-** then this routine returns SQLITE_FULL and does an immediate rollback.
-** All subsequent write attempts also return SQLITE_FULL until there
-** is a call to sqlite3PagerCommit() or sqlite3PagerRollback() to
-** reset.
+** Return a pointer to the root of the constructed binary tree.
 */
-static int pager_write(PgHdr *pPg){
-  void *pData = PGHDR_TO_DATA(pPg);
-  Pager *pPager = pPg->pPager;
-  int rc = SQLITE_OK;
-
-  /* Check for errors
-  */
-  if( pPager->errCode ){ 
-    return pPager->errCode;
+static struct RowSetEntry *rowSetNDeepTree(
+  struct RowSetEntry **ppList,
+  int iDepth
+){
+  struct RowSetEntry *p;         /* Root of the new tree */
+  struct RowSetEntry *pLeft;     /* Left subtree */
+  if( *ppList==0 ){
+    return 0;
   }
-  if( pPager->readOnly ){
-    return SQLITE_PERM;
+  if( iDepth==1 ){
+    p = *ppList;
+    *ppList = p->pRight;
+    p->pLeft = p->pRight = 0;
+    return p;
   }
+  pLeft = rowSetNDeepTree(ppList, iDepth-1);
+  p = *ppList;
+  if( p==0 ){
+    return pLeft;
+  }
+  p->pLeft = pLeft;
+  *ppList = p->pRight;
+  p->pRight = rowSetNDeepTree(ppList, iDepth-1);
+  return p;
+}
 
-  assert( !pPager->setMaster );
-
-  CHECK_PAGE(pPg);
+/*
+** Convert a sorted list of elements into a binary tree. Make the tree
+** as deep as it needs to be in order to contain the entire list.
+*/
+static struct RowSetEntry *rowSetListToTree(struct RowSetEntry *pList){
+  int iDepth;           /* Depth of the tree so far */
+  struct RowSetEntry *p;       /* Current tree root */
+  struct RowSetEntry *pLeft;   /* Left subtree */
 
-  /* If this page was previously acquired with noContent==1, that means
-  ** we didn't really read in the content of the page.  This can happen
-  ** (for example) when the page is being moved to the freelist.  But
-  ** now we are (perhaps) moving the page off of the freelist for
-  ** reuse and we need to know its original content so that content
-  ** can be stored in the rollback journal.  So do the read at this
-  ** time.
-  */
-  rc = pager_get_content(pPg);
-  if( rc ){
-    return rc;
+  assert( pList!=0 );
+  p = pList;
+  pList = p->pRight;
+  p->pLeft = p->pRight = 0;
+  for(iDepth=1; pList; iDepth++){
+    pLeft = p;
+    p = pList;
+    pList = p->pRight;
+    p->pLeft = pLeft;
+    p->pRight = rowSetNDeepTree(&pList, iDepth);
   }
+  return p;
+}
 
-  /* Mark the page as dirty.  If the page has already been written
-  ** to the journal then we can return right away.
-  */
-  makeDirty(pPg);
-  if( pPg->inJournal && (pageInStatement(pPg) || pPager->stmtInUse==0) ){
-    pPager->dirtyCache = 1;
-    pPager->dbModified = 1;
-  }else{
+/*
+** Convert the list in p->pEntry into a sorted list if it is not
+** sorted already.  If there is a binary tree on p->pTree, then
+** convert it into a list too and merge it into the p->pEntry list.
+*/
+static void rowSetToList(RowSet *p){
+  if( !p->isSorted ){
+    rowSetSort(p);
+  }
+  if( p->pTree ){
+    struct RowSetEntry *pHead, *pTail;
+    rowSetTreeToList(p->pTree, &pHead, &pTail);
+    p->pTree = 0;
+    p->pEntry = rowSetMerge(p->pEntry, pHead);
+  }
+}
 
-    /* If we get this far, it means that the page needs to be
-    ** written to the transaction journal or the ckeckpoint journal
-    ** or both.
-    **
-    ** First check to see that the transaction journal exists and
-    ** create it if it does not.
-    */
-    assert( pPager->state!=PAGER_UNLOCK );
-    rc = sqlite3PagerBegin(pPg, 0);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    assert( pPager->state>=PAGER_RESERVED );
-    if( !pPager->journalOpen && pPager->useJournal
-          && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
-      rc = pager_open_journal(pPager);
-      if( rc!=SQLITE_OK ) return rc;
+/*
+** Extract the smallest element from the RowSet.
+** Write the element into *pRowid.  Return 1 on success.  Return
+** 0 if the RowSet is already empty.
+**
+** After this routine has been called, the sqlite3RowSetInsert()
+** routine may not be called again.  
+*/
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
+  rowSetToList(p);
+  if( p->pEntry ){
+    *pRowid = p->pEntry->v;
+    p->pEntry = p->pEntry->pRight;
+    if( p->pEntry==0 ){
+      sqlite3RowSetClear(p);
     }
-    pPager->dirtyCache = 1;
-    pPager->dbModified = 1;
-  
-    /* The transaction journal now exists and we have a RESERVED or an
-    ** EXCLUSIVE lock on the main database file.  Write the current page to
-    ** the transaction journal if it is not there already.
-    */
-    if( !pPg->inJournal && (pPager->journalOpen || MEMDB) ){
-      if( (int)pPg->pgno <= pPager->origDbSize ){
-        if( MEMDB ){
-          PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-          PAGERTRACE3("JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
-          assert( pHist->pOrig==0 );
-          pHist->pOrig = sqlite3_malloc( pPager->pageSize );
-          if( !pHist->pOrig ){
-            return SQLITE_NOMEM;
-          }
-          memcpy(pHist->pOrig, PGHDR_TO_DATA(pPg), pPager->pageSize);
-        }else{
-          u32 cksum;
-          char *pData2;
-
-          /* We should never write to the journal file the page that
-          ** contains the database locks.  The following assert verifies
-          ** that we do not. */
-          assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
-          pData2 = CODEC2(pPager, pData, pPg->pgno, 7);
-          cksum = pager_cksum(pPager, (u8*)pData2);
-          rc = write32bits(pPager->jfd, pPager->journalOff, pPg->pgno);
-          if( rc==SQLITE_OK ){
-            rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize,
-                                pPager->journalOff + 4);
-            pPager->journalOff += pPager->pageSize+4;
-          }
-          if( rc==SQLITE_OK ){
-            rc = write32bits(pPager->jfd, pPager->journalOff, cksum);
-            pPager->journalOff += 4;
-          }
-          IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno, 
-                   pPager->journalOff, pPager->pageSize));
-          PAGER_INCR(sqlite3_pager_writej_count);
-          PAGERTRACE5("JOURNAL %d page %d needSync=%d hash(%08x)\n",
-               PAGERID(pPager), pPg->pgno, pPg->needSync, pager_pagehash(pPg));
-
-          /* An error has occured writing to the journal file. The 
-          ** transaction will be rolled back by the layer above.
-          */
-          if( rc!=SQLITE_OK ){
-            return rc;
-          }
+    return 1;
+  }else{
+    return 0;
+  }
+}
 
-          pPager->nRec++;
-          assert( pPager->pInJournal!=0 );
-          sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
-          pPg->needSync = !pPager->noSync;
-          if( pPager->stmtInUse ){
-            sqlite3BitvecSet(pPager->pInStmt, pPg->pgno);
-          }
-        }
-      }else{
-        pPg->needSync = !pPager->journalStarted && !pPager->noSync;
-        PAGERTRACE4("APPEND %d page %d needSync=%d\n",
-                PAGERID(pPager), pPg->pgno, pPg->needSync);
-      }
-      if( pPg->needSync ){
-        pPager->needSync = 1;
-      }
-      pPg->inJournal = 1;
-    }
-  
-    /* If the statement journal is open and the page is not in it,
-    ** then write the current page to the statement journal.  Note that
-    ** the statement journal format differs from the standard journal format
-    ** in that it omits the checksums and the header.
-    */
-    if( pPager->stmtInUse 
-     && !pageInStatement(pPg) 
-     && (int)pPg->pgno<=pPager->stmtSize 
-    ){
-      assert( pPg->inJournal || (int)pPg->pgno>pPager->origDbSize );
-      if( MEMDB ){
-        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-        assert( pHist->pStmt==0 );
-        pHist->pStmt = sqlite3_malloc( pPager->pageSize );
-        if( pHist->pStmt ){
-          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
-        }
-        PAGERTRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
-        page_add_to_stmt_list(pPg);
-      }else{
-        i64 offset = pPager->stmtNRec*(4+pPager->pageSize);
-        char *pData2 = CODEC2(pPager, pData, pPg->pgno, 7);
-        rc = write32bits(pPager->stfd, offset, pPg->pgno);
-        if( rc==SQLITE_OK ){
-          rc = sqlite3OsWrite(pPager->stfd, pData2, pPager->pageSize, offset+4);
-        }
-        PAGERTRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        pPager->stmtNRec++;
-        assert( pPager->pInStmt!=0 );
-        sqlite3BitvecSet(pPager->pInStmt, pPg->pgno);
-      }
+/*
+** Check to see if element iRowid was inserted into the the rowset as
+** part of any insert batch prior to iBatch.  Return 1 or 0.
+*/
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet *pRowSet, u8 iBatch, sqlite3_int64 iRowid){
+  struct RowSetEntry *p;
+  if( iBatch!=pRowSet->iBatch ){
+    if( pRowSet->pEntry ){
+      rowSetToList(pRowSet);
+      pRowSet->pTree = rowSetListToTree(pRowSet->pEntry);
+      pRowSet->pEntry = 0;
+      pRowSet->pLast = 0;
     }
+    pRowSet->iBatch = iBatch;
   }
-
-  /* Update the database size and return.
-  */
-  assert( pPager->state>=PAGER_SHARED );
-  if( pPager->dbSize<(int)pPg->pgno ){
-    pPager->dbSize = pPg->pgno;
-    if( !MEMDB && pPager->dbSize==PENDING_BYTE/pPager->pageSize ){
-      pPager->dbSize++;
+  p = pRowSet->pTree;
+  while( p ){
+    if( p->v<iRowid ){
+      p = p->pRight;
+    }else if( p->v>iRowid ){
+      p = p->pLeft;
+    }else{
+      return 1;
     }
   }
-  return rc;
+  return 0;
 }
 
+/************** End of rowset.c **********************************************/
+/************** Begin file pager.c *******************************************/
 /*
-** This function is used to mark a data-page as writable. It uses 
-** pager_write() to open a journal file (if it is not already open)
-** and write the page *pData to the journal.
+** 2001 September 15
 **
-** The difference between this function and pager_write() is that this
-** function also deals with the special case where 2 or more pages
-** fit on a single disk sector. In this case all co-resident pages
-** must have been written to the journal file before returning.
-*/
-SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
-  int rc = SQLITE_OK;
-
-  PgHdr *pPg = pDbPage;
-  Pager *pPager = pPg->pPager;
-  Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
-
-  pagerEnter(pPager);
-  if( !MEMDB && nPagePerSector>1 ){
-    Pgno nPageCount;          /* Total number of pages in database file */
-    Pgno pg1;                 /* First page of the sector pPg is located on. */
-    int nPage;                /* Number of pages starting at pg1 to journal */
-    int ii;
-    int needSync = 0;
-
-    /* Set the doNotSync flag to 1. This is because we cannot allow a journal
-    ** header to be written between the pages journaled by this function.
-    */
-    assert( pPager->doNotSync==0 );
-    pPager->doNotSync = 1;
-
-    /* This trick assumes that both the page-size and sector-size are
-    ** an integer power of 2. It sets variable pg1 to the identifier
-    ** of the first page of the sector pPg is located on.
-    */
-    pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
-
-    nPageCount = sqlite3PagerPagecount(pPager);
-    if( pPg->pgno>nPageCount ){
-      nPage = (pPg->pgno - pg1)+1;
-    }else if( (pg1+nPagePerSector-1)>nPageCount ){
-      nPage = nPageCount+1-pg1;
-    }else{
-      nPage = nPagePerSector;
-    }
-    assert(nPage>0);
-    assert(pg1<=pPg->pgno);
-    assert((pg1+nPage)>pPg->pgno);
-
-    for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
-      Pgno pg = pg1+ii;
-      PgHdr *pPage;
-      if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
-        if( pg!=PAGER_MJ_PGNO(pPager) ){
-          rc = sqlite3PagerGet(pPager, pg, &pPage);
-          if( rc==SQLITE_OK ){
-            rc = pager_write(pPage);
-            if( pPage->needSync ){
-              needSync = 1;
-            }
-            sqlite3PagerUnref(pPage);
-          }
-        }
-      }else if( (pPage = pager_lookup(pPager, pg))!=0 ){
-        if( pPage->needSync ){
-          needSync = 1;
-        }
-      }
-    }
-
-    /* If the PgHdr.needSync flag is set for any of the nPage pages 
-    ** starting at pg1, then it needs to be set for all of them. Because
-    ** writing to any of these nPage pages may damage the others, the
-    ** journal file must contain sync()ed copies of all of them
-    ** before any of them can be written out to the database file.
-    */
-    if( needSync ){
-      for(ii=0; ii<nPage && needSync; ii++){
-        PgHdr *pPage = pager_lookup(pPager, pg1+ii);
-        if( pPage ) pPage->needSync = 1;
-      }
-      assert(pPager->needSync);
-    }
-
-    assert( pPager->doNotSync==1 );
-    pPager->doNotSync = 0;
-  }else{
-    rc = pager_write(pDbPage);
-  }
-  pagerLeave(pPager);
-  return rc;
-}
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of the page cache subsystem or "pager".
+** 
+** The pager is used to access a database disk file.  It implements
+** atomic commit and rollback through the use of a journal file that
+** is separate from the database file.  The pager also implements file
+** locking to prevent two processes from writing the same database
+** file simultaneously, or one process from reading the database while
+** another is writing.
+**
+** @(#) $Id: pager.c,v 1.629 2009/08/10 17:48:57 drh Exp $
+*/
+#ifndef SQLITE_OMIT_DISKIO
 
 /*
-** Return TRUE if the page given in the argument was previously passed
-** to sqlite3PagerWrite().  In other words, return TRUE if it is ok
-** to change the content of the page.
+** Macros for troubleshooting.  Normally turned off
 */
-#ifndef NDEBUG
-SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage *pPg){
-  return pPg->dirty;
-}
+#if 0
+int sqlite3PagerTrace=1;  /* True to enable tracing */
+#define sqlite3DebugPrintf printf
+#define PAGERTRACE(X)     if( sqlite3PagerTrace ){ sqlite3DebugPrintf X; }
+#else
+#define PAGERTRACE(X)
 #endif
 
 /*
-** A call to this routine tells the pager that it is not necessary to
-** write the information on page pPg back to the disk, even though
-** that page might be marked as dirty.
-**
-** The overlying software layer calls this routine when all of the data
-** on the given page is unused.  The pager marks the page as clean so
-** that it does not get written to disk.
+** The following two macros are used within the PAGERTRACE() macros above
+** to print out file-descriptors. 
 **
-** Tests show that this optimization, together with the
-** sqlite3PagerDontRollback() below, more than double the speed
-** of large INSERT operations and quadruple the speed of large DELETEs.
-**
-** When this routine is called, set the alwaysRollback flag to true.
-** Subsequent calls to sqlite3PagerDontRollback() for the same page
-** will thereafter be ignored.  This is necessary to avoid a problem
-** where a page with data is added to the freelist during one part of
-** a transaction then removed from the freelist during a later part
-** of the same transaction and reused for some other purpose.  When it
-** is first added to the freelist, this routine is called.  When reused,
-** the sqlite3PagerDontRollback() routine is called.  But because the
-** page contains critical data, we still need to be sure it gets
-** rolled back in spite of the sqlite3PagerDontRollback() call.
-*/
-SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage *pDbPage){
-  PgHdr *pPg = pDbPage;
-  Pager *pPager = pPg->pPager;
-
-  if( MEMDB ) return;
-  pagerEnter(pPager);
-  pPg->alwaysRollback = 1;
-  if( pPg->dirty && !pPager->stmtInUse ){
-    assert( pPager->state>=PAGER_SHARED );
-    if( pPager->dbSize==(int)pPg->pgno && pPager->origDbSize<pPager->dbSize ){
-      /* If this pages is the last page in the file and the file has grown
-      ** during the current transaction, then do NOT mark the page as clean.
-      ** When the database file grows, we must make sure that the last page
-      ** gets written at least once so that the disk file will be the correct
-      ** size. If you do not write this page and the size of the file
-      ** on the disk ends up being too small, that can lead to database
-      ** corruption during the next transaction.
-      */
-    }else{
-      PAGERTRACE3("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager));
-      IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
-      makeClean(pPg);
-#ifdef SQLITE_CHECK_PAGES
-      pPg->pageHash = pager_pagehash(pPg);
-#endif
-    }
-  }
-  pagerLeave(pPager);
-}
+** PAGERID() takes a pointer to a Pager struct as its argument. The
+** associated file-descriptor is returned. FILEHANDLEID() takes an sqlite3_file
+** struct as its argument.
+*/
+#define PAGERID(p) ((int)(p->fd))
+#define FILEHANDLEID(fd) ((int)fd)
 
 /*
-** A call to this routine tells the pager that if a rollback occurs,
-** it is not necessary to restore the data on the given page.  This
-** means that the pager does not have to record the given page in the
-** rollback journal.
+** The page cache as a whole is always in one of the following
+** states:
+**
+**   PAGER_UNLOCK        The page cache is not currently reading or 
+**                       writing the database file.  There is no
+**                       data held in memory.  This is the initial
+**                       state.
+**
+**   PAGER_SHARED        The page cache is reading the database.
+**                       Writing is not permitted.  There can be
+**                       multiple readers accessing the same database
+**                       file at the same time.
+**
+**   PAGER_RESERVED      This process has reserved the database for writing
+**                       but has not yet made any changes.  Only one process
+**                       at a time can reserve the database.  The original
+**                       database file has not been modified so other
+**                       processes may still be reading the on-disk
+**                       database file.
+**
+**   PAGER_EXCLUSIVE     The page cache is writing the database.
+**                       Access is exclusive.  No other processes or
+**                       threads can be reading or writing while one
+**                       process is writing.
+**
+**   PAGER_SYNCED        The pager moves to this state from PAGER_EXCLUSIVE
+**                       after all dirty pages have been written to the
+**                       database file and the file has been synced to
+**                       disk. All that remains to do is to remove or
+**                       truncate the journal file and the transaction 
+**                       will be committed.
 **
-** If we have not yet actually read the content of this page (if
-** the PgHdr.needRead flag is set) then this routine acts as a promise
-** that we will never need to read the page content in the future.
-** so the needRead flag can be cleared at this point.
+** The page cache comes up in PAGER_UNLOCK.  The first time a
+** sqlite3PagerGet() occurs, the state transitions to PAGER_SHARED.
+** After all pages have been released using sqlite_page_unref(),
+** the state transitions back to PAGER_UNLOCK.  The first time
+** that sqlite3PagerWrite() is called, the state transitions to
+** PAGER_RESERVED.  (Note that sqlite3PagerWrite() can only be
+** called on an outstanding page which means that the pager must
+** be in PAGER_SHARED before it transitions to PAGER_RESERVED.)
+** PAGER_RESERVED means that there is an open rollback journal.
+** The transition to PAGER_EXCLUSIVE occurs before any changes
+** are made to the database file, though writes to the rollback
+** journal occurs with just PAGER_RESERVED.  After an sqlite3PagerRollback()
+** or sqlite3PagerCommitPhaseTwo(), the state can go back to PAGER_SHARED,
+** or it can stay at PAGER_EXCLUSIVE if we are in exclusive access mode.
 */
-SQLITE_PRIVATE void sqlite3PagerDontRollback(DbPage *pPg){
-  Pager *pPager = pPg->pPager;
-
-  pagerEnter(pPager);
-  assert( pPager->state>=PAGER_RESERVED );
-
-  /* If the journal file is not open, or DontWrite() has been called on
-  ** this page (DontWrite() sets the alwaysRollback flag), then this
-  ** function is a no-op.
-  */
-  if( pPager->journalOpen==0 || pPg->alwaysRollback || pPager->alwaysRollback ){
-    pagerLeave(pPager);
-    return;
-  }
-  assert( !MEMDB );    /* For a memdb, pPager->journalOpen is always 0 */
+#define PAGER_UNLOCK      0
+#define PAGER_SHARED      1   /* same as SHARED_LOCK */
+#define PAGER_RESERVED    2   /* same as RESERVED_LOCK */
+#define PAGER_EXCLUSIVE   4   /* same as EXCLUSIVE_LOCK */
+#define PAGER_SYNCED      5
 
-#ifdef SQLITE_SECURE_DELETE
-  if( pPg->inJournal || (int)pPg->pgno > pPager->origDbSize ){
-    return;
-  }
+/*
+** A macro used for invoking the codec if there is one
+*/
+#ifdef SQLITE_HAS_CODEC
+# define CODEC1(P,D,N,X,E) \
+    if( P->xCodec && P->xCodec(P->pCodec,D,N,X)==0 ){ E; }
+# define CODEC2(P,D,N,X,E,O) \
+    if( P->xCodec==0 ){ O=(char*)D; }else \
+    if( (O=(char*)(P->xCodec(P->pCodec,D,N,X)))==0 ){ E; }
+#else
+# define CODEC1(P,D,N,X,E)   /* NO-OP */
+# define CODEC2(P,D,N,X,E,O) O=(char*)D
 #endif
 
-  /* If SECURE_DELETE is disabled, then there is no way that this
-  ** routine can be called on a page for which sqlite3PagerDontWrite()
-  ** has not been previously called during the same transaction.
-  ** And if DontWrite() has previously been called, the following
-  ** conditions must be met.
-  */
-  assert( !pPg->inJournal && (int)pPg->pgno <= pPager->origDbSize );
-
-  assert( pPager->pInJournal!=0 );
-  sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
-  pPg->inJournal = 1;
-  pPg->needRead = 0;
-  if( pPager->stmtInUse ){
-    assert( pPager->stmtSize >= pPager->origDbSize );
-    sqlite3BitvecSet(pPager->pInStmt, pPg->pgno);
-  }
-  PAGERTRACE3("DONT_ROLLBACK page %d of %d\n", pPg->pgno, PAGERID(pPager));
-  IOTRACE(("GARBAGE %p %d\n", pPager, pPg->pgno))
-  pagerLeave(pPager);
-}
-
-
 /*
-** This routine is called to increment the database file change-counter,
-** stored at byte 24 of the pager file.
+** The maximum allowed sector size. 64KiB. If the xSectorsize() method 
+** returns a value larger than this, then MAX_SECTOR_SIZE is used instead.
+** This could conceivably cause corruption following a power failure on
+** such a system. This is currently an undocumented limit.
 */
-static int pager_incr_changecounter(Pager *pPager, int isDirect){
-  PgHdr *pPgHdr;
-  u32 change_counter;
-  int rc = SQLITE_OK;
-
-  if( !pPager->changeCountDone ){
-    /* Open page 1 of the file for writing. */
-    rc = sqlite3PagerGet(pPager, 1, &pPgHdr);
-    if( rc!=SQLITE_OK ) return rc;
-
-    if( !isDirect ){
-      rc = sqlite3PagerWrite(pPgHdr);
-      if( rc!=SQLITE_OK ){
-        sqlite3PagerUnref(pPgHdr);
-        return rc;
-      }
-    }
-
-    /* Increment the value just read and write it back to byte 24. */
-    change_counter = sqlite3Get4byte((u8*)pPager->dbFileVers);
-    change_counter++;
-    put32bits(((char*)PGHDR_TO_DATA(pPgHdr))+24, change_counter);
-
-    if( isDirect && pPager->fd->pMethods ){
-      const void *zBuf = PGHDR_TO_DATA(pPgHdr);
-      rc = sqlite3OsWrite(pPager->fd, zBuf, pPager->pageSize, 0);
-    }
-
-    /* Release the page reference. */
-    sqlite3PagerUnref(pPgHdr);
-    pPager->changeCountDone = 1;
-  }
-  return rc;
-}
+#define MAX_SECTOR_SIZE 0x10000
 
 /*
-** Sync the pager file to disk.
+** An instance of the following structure is allocated for each active
+** savepoint and statement transaction in the system. All such structures
+** are stored in the Pager.aSavepoint[] array, which is allocated and
+** resized using sqlite3Realloc().
+**
+** When a savepoint is created, the PagerSavepoint.iHdrOffset field is
+** set to 0. If a journal-header is written into the main journal while
+** the savepoint is active, then iHdrOffset is set to the byte offset 
+** immediately following the last journal record written into the main
+** journal before the journal-header. This is required during savepoint
+** rollback (see pagerPlaybackSavepoint()).
 */
-SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager){
-  int rc;
-  pagerEnter(pPager);
-  rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
-  pagerLeave(pPager);
-  return rc;
-}
+typedef struct PagerSavepoint PagerSavepoint;
+struct PagerSavepoint {
+  i64 iOffset;                 /* Starting offset in main journal */
+  i64 iHdrOffset;              /* See above */
+  Bitvec *pInSavepoint;        /* Set of pages in this savepoint */
+  Pgno nOrig;                  /* Original number of pages in file */
+  Pgno iSubRec;                /* Index of first record in sub-journal */
+};
 
 /*
-** Sync the database file for the pager pPager. zMaster points to the name
-** of a master journal file that should be written into the individual
-** journal file. zMaster may be NULL, which is interpreted as no master
-** journal (a single database transaction).
+** A open page cache is an instance of the following structure.
 **
-** This routine ensures that the journal is synced, all dirty pages written
-** to the database file and the database file synced. The only thing that
-** remains to commit the transaction is to delete the journal file (or
-** master journal file if specified).
+** errCode
 **
-** Note that if zMaster==NULL, this does not overwrite a previous value
-** passed to an sqlite3PagerCommitPhaseOne() call.
+**   Pager.errCode may be set to SQLITE_IOERR, SQLITE_CORRUPT, or
+**   or SQLITE_FULL. Once one of the first three errors occurs, it persists
+**   and is returned as the result of every major pager API call.  The
+**   SQLITE_FULL return code is slightly different. It persists only until the
+**   next successful rollback is performed on the pager cache. Also,
+**   SQLITE_FULL does not affect the sqlite3PagerGet() and sqlite3PagerLookup()
+**   APIs, they may still be used successfully.
 **
-** If parameter nTrunc is non-zero, then the pager file is truncated to
-** nTrunc pages (this is used by auto-vacuum databases).
+** dbSizeValid, dbSize, dbOrigSize, dbFileSize
 **
-** If the final parameter - noSync - is true, then the database file itself
-** is not synced. The caller must call sqlite3PagerSync() directly to
-** sync the database file before calling CommitPhaseTwo() to delete the
-** journal file in this case.
+**   Managing the size of the database file in pages is a little complicated.
+**   The variable Pager.dbSize contains the number of pages that the database
+**   image currently contains. As the database image grows or shrinks this
+**   variable is updated. The variable Pager.dbFileSize contains the number
+**   of pages in the database file. This may be different from Pager.dbSize
+**   if some pages have been appended to the database image but not yet written
+**   out from the cache to the actual file on disk. Or if the image has been
+**   truncated by an incremental-vacuum operation. The Pager.dbOrigSize variable
+**   contains the number of pages in the database image when the current
+**   transaction was opened. The contents of all three of these variables is
+**   only guaranteed to be correct if the boolean Pager.dbSizeValid is true.
+**
+**   TODO: Under what conditions is dbSizeValid set? Cleared?
+**
+** changeCountDone
+**
+**   This boolean variable is used to make sure that the change-counter 
+**   (the 4-byte header field at byte offset 24 of the database file) is 
+**   not updated more often than necessary. 
+**
+**   It is set to true when the change-counter field is updated, which 
+**   can only happen if an exclusive lock is held on the database file.
+**   It is cleared (set to false) whenever an exclusive lock is 
+**   relinquished on the database file. Each time a transaction is committed,
+**   The changeCountDone flag is inspected. If it is true, the work of
+**   updating the change-counter is omitted for the current transaction.
+**
+**   This mechanism means that when running in exclusive mode, a connection 
+**   need only update the change-counter once, for the first transaction
+**   committed.
+**
+** dbModified
+**
+**   The dbModified flag is set whenever a database page is dirtied.
+**   It is cleared at the end of each transaction.
+**
+**   It is used when committing or otherwise ending a transaction. If
+**   the dbModified flag is clear then less work has to be done.
+**
+** journalStarted
+**
+**   This flag is set whenever the the main journal is synced. 
+**
+**   The point of this flag is that it must be set after the 
+**   first journal header in a journal file has been synced to disk.
+**   After this has happened, new pages appended to the database 
+**   do not need the PGHDR_NEED_SYNC flag set, as they do not need
+**   to wait for a journal sync before they can be written out to
+**   the database file (see function pager_write()).
+**   
+** setMaster
+**
+**   This variable is used to ensure that the master journal file name
+**   (if any) is only written into the journal file once.
+**
+**   When committing a transaction, the master journal file name (if any)
+**   may be written into the journal file while the pager is still in
+**   PAGER_RESERVED state (see CommitPhaseOne() for the action). It
+**   then attempts to upgrade to an exclusive lock. If this attempt
+**   fails, then SQLITE_BUSY may be returned to the user and the user
+**   may attempt to commit the transaction again later (calling
+**   CommitPhaseOne() again). This flag is used to ensure that the 
+**   master journal name is only written to the journal file the first
+**   time CommitPhaseOne() is called.
+**
+** doNotSync
+**
+**   This variable is set and cleared by sqlite3PagerWrite().
+**
+** needSync
+**
+**   TODO: It might be easier to set this variable in writeJournalHdr()
+**   and writeMasterJournal() only. Change its meaning to "unsynced data
+**   has been written to the journal".
+**
+** subjInMemory
+**
+**   This is a boolean variable. If true, then any required sub-journal
+**   is opened as an in-memory journal file. If false, then in-memory
+**   sub-journals are only used for in-memory pager files.
 */
-SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
-  Pager *pPager, 
-  const char *zMaster, 
-  Pgno nTrunc,
-  int noSync
-){
-  int rc = SQLITE_OK;
-
-  /* If no changes have been made, we can leave the transaction early.
-  */
-  if( pPager->dbModified==0 &&
-        (pPager->journalMode!=PAGER_JOURNALMODE_DELETE ||
-          pPager->exclusiveMode!=0) ){
-    assert( pPager->dirtyCache==0 || pPager->journalOpen==0 );
-    return SQLITE_OK;
-  }
-
-  PAGERTRACE4("DATABASE SYNC: File=%s zMaster=%s nTrunc=%d\n", 
-      pPager->zFilename, zMaster, nTrunc);
-  pagerEnter(pPager);
+struct Pager {
+  sqlite3_vfs *pVfs;          /* OS functions to use for IO */
+  u8 exclusiveMode;           /* Boolean. True if locking_mode==EXCLUSIVE */
+  u8 journalMode;             /* On of the PAGER_JOURNALMODE_* values */
+  u8 useJournal;              /* Use a rollback journal on this file */
+  u8 noReadlock;              /* Do not bother to obtain readlocks */
+  u8 noSync;                  /* Do not sync the journal if true */
+  u8 fullSync;                /* Do extra syncs of the journal for robustness */
+  u8 sync_flags;              /* One of SYNC_NORMAL or SYNC_FULL */
+  u8 tempFile;                /* zFilename is a temporary file */
+  u8 readOnly;                /* True for a read-only database */
+  u8 memDb;                   /* True to inhibit all file I/O */
 
-  /* If this is an in-memory db, or no pages have been written to, or this
-  ** function has already been called, it is a no-op.
+  /* The following block contains those class members that are dynamically
+  ** modified during normal operations. The other variables in this structure
+  ** are either constant throughout the lifetime of the pager, or else
+  ** used to store configuration parameters that affect the way the pager 
+  ** operates.
+  **
+  ** The 'state' variable is described in more detail along with the
+  ** descriptions of the values it may take - PAGER_UNLOCK etc. Many of the
+  ** other variables in this block are described in the comment directly 
+  ** above this class definition.
   */
-  if( pPager->state!=PAGER_SYNCED && !MEMDB && pPager->dirtyCache ){
-    PgHdr *pPg;
-
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-    /* The atomic-write optimization can be used if all of the
-    ** following are true:
-    **
-    **    + The file-system supports the atomic-write property for
-    **      blocks of size page-size, and
-    **    + This commit is not part of a multi-file transaction, and
-    **    + Exactly one page has been modified and store in the journal file.
-    **
-    ** If the optimization can be used, then the journal file will never
-    ** be created for this transaction.
-    */
-    int useAtomicWrite = (
-        !zMaster && 
-        pPager->journalOpen &&
-        pPager->journalOff==jrnlBufferSize(pPager) && 
-        nTrunc==0 && 
-        (0==pPager->pDirty || 0==pPager->pDirty->pDirty)
-    );
-    assert( pPager->journalOpen || pPager->journalMode==PAGER_JOURNALMODE_OFF );
-    if( useAtomicWrite ){
-      /* Update the nRec field in the journal file. */
-      int offset = pPager->journalHdr + sizeof(aJournalMagic);
-      assert(pPager->nRec==1);
-      rc = write32bits(pPager->jfd, offset, pPager->nRec);
-
-      /* Update the db file change counter. The following call will modify
-      ** the in-memory representation of page 1 to include the updated
-      ** change counter and then write page 1 directly to the database
-      ** file. Because of the atomic-write property of the host file-system, 
-      ** this is safe.
-      */
-      if( rc==SQLITE_OK ){
-        rc = pager_incr_changecounter(pPager, 1);
-      }
-    }else{
-      rc = sqlite3JournalCreate(pPager->jfd);
-    }
+  u8 state;                   /* PAGER_UNLOCK, _SHARED, _RESERVED, etc. */
+  u8 dbModified;              /* True if there are any changes to the Db */
+  u8 needSync;                /* True if an fsync() is needed on the journal */
+  u8 journalStarted;          /* True if header of journal is synced */
+  u8 changeCountDone;         /* Set after incrementing the change-counter */
+  u8 setMaster;               /* True if a m-j name has been written to jrnl */
+  u8 doNotSync;               /* Boolean. While true, do not spill the cache */
+  u8 dbSizeValid;             /* Set when dbSize is correct */
+  u8 subjInMemory;            /* True to use in-memory sub-journals */
+  Pgno dbSize;                /* Number of pages in the database */
+  Pgno dbOrigSize;            /* dbSize before the current transaction */
+  Pgno dbFileSize;            /* Number of pages in the database file */
+  int errCode;                /* One of several kinds of errors */
+  int nRec;                   /* Pages journalled since last j-header written */
+  u32 cksumInit;              /* Quasi-random value added to every checksum */
+  u32 nSubRec;                /* Number of records written to sub-journal */
+  Bitvec *pInJournal;         /* One bit for each page in the database file */
+  sqlite3_file *fd;           /* File descriptor for database */
+  sqlite3_file *jfd;          /* File descriptor for main journal */
+  sqlite3_file *sjfd;         /* File descriptor for sub-journal */
+  i64 journalOff;             /* Current write offset in the journal file */
+  i64 journalHdr;             /* Byte offset to previous journal header */
+  PagerSavepoint *aSavepoint; /* Array of active savepoints */
+  int nSavepoint;             /* Number of elements in aSavepoint[] */
+  char dbFileVers[16];        /* Changes whenever database file changes */
+  u32 sectorSize;             /* Assumed sector size during rollback */
 
-    if( !useAtomicWrite && rc==SQLITE_OK )
+  u16 nExtra;                 /* Add this many bytes to each in-memory page */
+  i16 nReserve;               /* Number of unused bytes at end of each page */
+  u32 vfsFlags;               /* Flags for sqlite3_vfs.xOpen() */
+  int pageSize;               /* Number of bytes in a page */
+  Pgno mxPgno;                /* Maximum allowed size of the database */
+  char *zFilename;            /* Name of the database file */
+  char *zJournal;             /* Name of the journal file */
+  int (*xBusyHandler)(void*); /* Function to call when busy */
+  void *pBusyHandlerArg;      /* Context argument for xBusyHandler */
+#ifdef SQLITE_TEST
+  int nHit, nMiss;            /* Cache hits and missing */
+  int nRead, nWrite;          /* Database pages read/written */
 #endif
-
-    /* If a master journal file name has already been written to the
-    ** journal file, then no sync is required. This happens when it is
-    ** written, then the process fails to upgrade from a RESERVED to an
-    ** EXCLUSIVE lock. The next time the process tries to commit the
-    ** transaction the m-j name will have already been written.
-    */
-    if( !pPager->setMaster ){
-      rc = pager_incr_changecounter(pPager, 0);
-      if( rc!=SQLITE_OK ) goto sync_exit;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( nTrunc!=0 ){
-        /* If this transaction has made the database smaller, then all pages
-        ** being discarded by the truncation must be written to the journal
-        ** file.
-        */
-        Pgno i;
-        int iSkip = PAGER_MJ_PGNO(pPager);
-        for( i=nTrunc+1; i<=pPager->origDbSize; i++ ){
-          if( !sqlite3BitvecTest(pPager->pInJournal, i) && i!=iSkip ){
-            rc = sqlite3PagerGet(pPager, i, &pPg);
-            if( rc!=SQLITE_OK ) goto sync_exit;
-            rc = sqlite3PagerWrite(pPg);
-            sqlite3PagerUnref(pPg);
-            if( rc!=SQLITE_OK ) goto sync_exit;
-          }
-        } 
-      }
+  void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
+#ifdef SQLITE_HAS_CODEC
+  void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
+  void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
+  void (*xCodecFree)(void*);             /* Destructor for the codec */
+  void *pCodec;               /* First argument to xCodec... methods */
 #endif
-      rc = writeMasterJournal(pPager, zMaster);
-      if( rc!=SQLITE_OK ) goto sync_exit;
-      rc = syncJournal(pPager);
-    }
-    if( rc!=SQLITE_OK ) goto sync_exit;
+  char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
+  i64 journalSizeLimit;       /* Size limit for persistent journal files */
+  PCache *pPCache;            /* Pointer to page cache object */
+  sqlite3_backup *pBackup;    /* Pointer to list of ongoing backup processes */
+};
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( nTrunc!=0 ){
-      rc = sqlite3PagerTruncate(pPager, nTrunc);
-      if( rc!=SQLITE_OK ) goto sync_exit;
-    }
+/*
+** The following global variables hold counters used for
+** testing purposes only.  These variables do not exist in
+** a non-testing build.  These variables are not thread-safe.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_pager_readdb_count = 0;    /* Number of full pages read from DB */
+SQLITE_API int sqlite3_pager_writedb_count = 0;   /* Number of full pages written to DB */
+SQLITE_API int sqlite3_pager_writej_count = 0;    /* Number of pages written to journal */
+# define PAGER_INCR(v)  v++
+#else
+# define PAGER_INCR(v)
 #endif
 
-    /* Write all dirty pages to the database file */
-    pPg = pager_get_all_dirty_pages(pPager);
-    rc = pager_write_pagelist(pPg);
-    if( rc!=SQLITE_OK ){
-      assert( rc!=SQLITE_IOERR_BLOCKED );
-      /* The error might have left the dirty list all fouled up here,
-      ** but that does not matter because if the if the dirty list did
-      ** get corrupted, then the transaction will roll back and
-      ** discard the dirty list.  There is an assert in
-      ** pager_get_all_dirty_pages() that verifies that no attempt
-      ** is made to use an invalid dirty list.
-      */
-      goto sync_exit;
-    }
-    pPager->pDirty = 0;
-
-    /* Sync the database file. */
-    if( !pPager->noSync && !noSync ){
-      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
-    }
-    IOTRACE(("DBSYNC %p\n", pPager))
-
-    pPager->state = PAGER_SYNCED;
-  }else if( MEMDB && nTrunc!=0 ){
-    rc = sqlite3PagerTruncate(pPager, nTrunc);
-  }
-
-sync_exit:
-  if( rc==SQLITE_IOERR_BLOCKED ){
-    /* pager_incr_changecounter() may attempt to obtain an exclusive
-     * lock to spill the cache and return IOERR_BLOCKED. But since 
-     * there is no chance the cache is inconsistent, it is
-     * better to return SQLITE_BUSY.
-     */
-    rc = SQLITE_BUSY;
-  }
-  pagerLeave(pPager);
-  return rc;
-}
 
 
 /*
-** Commit all changes to the database and release the write lock.
+** Journal files begin with the following magic string.  The data
+** was obtained from /dev/random.  It is used only as a sanity check.
 **
-** If the commit fails for any reason, a rollback attempt is made
-** and an error code is returned.  If the commit worked, SQLITE_OK
-** is returned.
+** Since version 2.8.0, the journal format contains additional sanity
+** checking information.  If the power fails while the journal is being
+** written, semi-random garbage data might appear in the journal
+** file after power is restored.  If an attempt is then made
+** to roll the journal back, the database could be corrupted.  The additional
+** sanity checking data is an attempt to discover the garbage in the
+** journal and ignore it.
+**
+** The sanity checking information for the new journal format consists
+** of a 32-bit checksum on each page of data.  The checksum covers both
+** the page number and the pPager->pageSize bytes of data for the page.
+** This cksum is initialized to a 32-bit random value that appears in the
+** journal file right after the header.  The random initializer is important,
+** because garbage data that appears at the end of a journal is likely
+** data that was once in other files that have now been deleted.  If the
+** garbage data came from an obsolete journal file, the checksums might
+** be correct.  But by initializing the checksum to random value which
+** is different for every journal, we minimize that risk.
 */
-SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager *pPager){
-  int rc;
-  PgHdr *pPg;
-
-  if( pPager->errCode ){
-    return pPager->errCode;
-  }
-  if( pPager->state<PAGER_RESERVED ){
-    return SQLITE_ERROR;
-  }
-  if( pPager->dbModified==0 &&
-        (pPager->journalMode!=PAGER_JOURNALMODE_DELETE ||
-          pPager->exclusiveMode!=0) ){
-    assert( pPager->dirtyCache==0 || pPager->journalOpen==0 );
-    return SQLITE_OK;
-  }
-  pagerEnter(pPager);
-  PAGERTRACE2("COMMIT %d\n", PAGERID(pPager));
-  if( MEMDB ){
-    pPg = pager_get_all_dirty_pages(pPager);
-    while( pPg ){
-      PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-      clearHistory(pHist);
-      pPg->dirty = 0;
-      pPg->inJournal = 0;
-      pHist->inStmt = 0;
-      pPg->needSync = 0;
-      pHist->pPrevStmt = pHist->pNextStmt = 0;
-      pPg = pPg->pDirty;
-    }
-    pPager->pDirty = 0;
-#ifndef NDEBUG
-    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-      PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-      assert( !pPg->alwaysRollback );
-      assert( !pHist->pOrig );
-      assert( !pHist->pStmt );
-    }
-#endif
-    pPager->pStmt = 0;
-    pPager->state = PAGER_SHARED;
-    pagerLeave(pPager);
-    return SQLITE_OK;
-  }
-  assert( pPager->state==PAGER_SYNCED || !pPager->dirtyCache );
-  rc = pager_end_transaction(pPager, pPager->setMaster);
-  rc = pager_error(pPager, rc);
-  pagerLeave(pPager);
-  return rc;
-}
+static const unsigned char aJournalMagic[] = {
+  0xd9, 0xd5, 0x05, 0xf9, 0x20, 0xa1, 0x63, 0xd7,
+};
 
 /*
-** Rollback all changes.  The database falls back to PAGER_SHARED mode.
-** All in-memory cache pages revert to their original data contents.
-** The journal is deleted.
-**
-** This routine cannot fail unless some other process is not following
-** the correct locking protocol or unless some other
-** process is writing trash into the journal file (SQLITE_CORRUPT) or
-** unless a prior malloc() failed (SQLITE_NOMEM).  Appropriate error
-** codes are returned for all these occasions.  Otherwise,
-** SQLITE_OK is returned.
+** The size of the of each page record in the journal is given by
+** the following macro.
 */
-SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
-  int rc;
-  PAGERTRACE2("ROLLBACK %d\n", PAGERID(pPager));
-  if( MEMDB ){
-    PgHdr *p;
-    for(p=pPager->pAll; p; p=p->pNextAll){
-      PgHistory *pHist;
-      assert( !p->alwaysRollback );
-      if( !p->dirty ){
-        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pOrig );
-        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pStmt );
-        continue;
-      }
-
-      pHist = PGHDR_TO_HIST(p, pPager);
-      if( pHist->pOrig ){
-        memcpy(PGHDR_TO_DATA(p), pHist->pOrig, pPager->pageSize);
-        PAGERTRACE3("ROLLBACK-PAGE %d of %d\n", p->pgno, PAGERID(pPager));
-      }else{
-        PAGERTRACE3("PAGE %d is clean on %d\n", p->pgno, PAGERID(pPager));
-      }
-      clearHistory(pHist);
-      p->dirty = 0;
-      p->inJournal = 0;
-      pHist->inStmt = 0;
-      pHist->pPrevStmt = pHist->pNextStmt = 0;
-      if( pPager->xReiniter ){
-        pPager->xReiniter(p, pPager->pageSize);
-      }
-    }
-    pPager->pDirty = 0;
-    pPager->pStmt = 0;
-    pPager->dbSize = pPager->origDbSize;
-    pager_truncate_cache(pPager);
-    pPager->stmtInUse = 0;
-    pPager->state = PAGER_SHARED;
-    return SQLITE_OK;
-  }
-
-  pagerEnter(pPager);
-  if( !pPager->dirtyCache || !pPager->journalOpen ){
-    rc = pager_end_transaction(pPager, pPager->setMaster);
-    pagerLeave(pPager);
-    return rc;
-  }
-
-  if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
-    if( pPager->state>=PAGER_EXCLUSIVE ){
-      pager_playback(pPager, 0);
-    }
-    pagerLeave(pPager);
-    return pPager->errCode;
-  }
-  if( pPager->state==PAGER_RESERVED ){
-    int rc2;
-    rc = pager_playback(pPager, 0);
-    rc2 = pager_end_transaction(pPager, pPager->setMaster);
-    if( rc==SQLITE_OK ){
-      rc = rc2;
-    }
-  }else{
-    rc = pager_playback(pPager, 0);
-  }
-  /* pager_reset(pPager); */
-  pPager->dbSize = -1;
+#define JOURNAL_PG_SZ(pPager)  ((pPager->pageSize) + 8)
 
-  /* If an error occurs during a ROLLBACK, we can no longer trust the pager
-  ** cache. So call pager_error() on the way out to make any error 
-  ** persistent.
-  */
-  rc = pager_error(pPager, rc);
-  pagerLeave(pPager);
-  return rc;
-}
+/*
+** The journal header size for this pager. This is usually the same 
+** size as a single disk sector. See also setSectorSize().
+*/
+#define JOURNAL_HDR_SZ(pPager) (pPager->sectorSize)
 
 /*
-** Return TRUE if the database file is opened read-only.  Return FALSE
-** if the database is (in theory) writable.
+** The macro MEMDB is true if we are dealing with an in-memory database.
+** We do this as a macro so that if the SQLITE_OMIT_MEMORYDB macro is set,
+** the value of MEMDB will be a constant and the compiler will optimize
+** out code that would never execute.
 */
-SQLITE_PRIVATE int sqlite3PagerIsreadonly(Pager *pPager){
-  return pPager->readOnly;
-}
+#ifdef SQLITE_OMIT_MEMORYDB
+# define MEMDB 0
+#else
+# define MEMDB pPager->memDb
+#endif
 
 /*
-** Return the number of references to the pager.
+** The maximum legal page number is (2^31 - 1).
 */
-SQLITE_PRIVATE int sqlite3PagerRefcount(Pager *pPager){
-  return pPager->nRef;
-}
+#define PAGER_MAX_PGNO 2147483647
 
-#ifdef SQLITE_TEST
+#ifndef NDEBUG 
 /*
-** This routine is used for testing and analysis only.
+** Usage:
+**
+**   assert( assert_pager_state(pPager) );
 */
-SQLITE_PRIVATE int *sqlite3PagerStats(Pager *pPager){
-  static int a[11];
-  a[0] = pPager->nRef;
-  a[1] = pPager->nPage;
-  a[2] = pPager->mxPage;
-  a[3] = pPager->dbSize;
-  a[4] = pPager->state;
-  a[5] = pPager->errCode;
-  a[6] = pPager->nHit;
-  a[7] = pPager->nMiss;
-  a[8] = 0;  /* Used to be pPager->nOvfl */
-  a[9] = pPager->nRead;
-  a[10] = pPager->nWrite;
-  return a;
+static int assert_pager_state(Pager *pPager){
+
+  /* A temp-file is always in PAGER_EXCLUSIVE or PAGER_SYNCED state. */
+  assert( pPager->tempFile==0 || pPager->state>=PAGER_EXCLUSIVE );
+
+  /* The changeCountDone flag is always set for temp-files */
+  assert( pPager->tempFile==0 || pPager->changeCountDone );
+
+  return 1;
 }
 #endif
 
 /*
-** Set the statement rollback point.
+** Return true if it is necessary to write page *pPg into the sub-journal.
+** A page needs to be written into the sub-journal if there exists one
+** or more open savepoints for which:
 **
-** This routine should be called with the transaction journal already
-** open.  A new statement journal is created that can be used to rollback
-** changes of a single SQL command within a larger transaction.
+**   * The page-number is less than or equal to PagerSavepoint.nOrig, and
+**   * The bit corresponding to the page-number is not set in
+**     PagerSavepoint.pInSavepoint.
 */
-static int pagerStmtBegin(Pager *pPager){
-  int rc;
-  assert( !pPager->stmtInUse );
-  assert( pPager->state>=PAGER_SHARED );
-  assert( pPager->dbSize>=0 );
-  PAGERTRACE2("STMT-BEGIN %d\n", PAGERID(pPager));
-  if( MEMDB ){
-    pPager->stmtInUse = 1;
-    pPager->stmtSize = pPager->dbSize;
-    return SQLITE_OK;
-  }
-  if( !pPager->journalOpen ){
-    pPager->stmtAutoopen = 1;
-    return SQLITE_OK;
-  }
-  assert( pPager->journalOpen );
-  pagerLeave(pPager);
-  assert( pPager->pInStmt==0 );
-  pPager->pInStmt = sqlite3BitvecCreate(pPager->dbSize);
-  pagerEnter(pPager);
-  if( pPager->pInStmt==0 ){
-    /* sqlite3OsLock(pPager->fd, SHARED_LOCK); */
-    return SQLITE_NOMEM;
-  }
-  pPager->stmtJSize = pPager->journalOff;
-  pPager->stmtSize = pPager->dbSize;
-  pPager->stmtHdrOff = 0;
-  pPager->stmtCksum = pPager->cksumInit;
-  if( !pPager->stmtOpen ){
-    rc = sqlite3PagerOpentemp(pPager->pVfs, pPager->stfd, pPager->zStmtJrnl,
-                              SQLITE_OPEN_SUBJOURNAL);
-    if( rc ){
-      goto stmt_begin_failed;
+static int subjRequiresPage(PgHdr *pPg){
+  Pgno pgno = pPg->pgno;
+  Pager *pPager = pPg->pPager;
+  int i;
+  for(i=0; i<pPager->nSavepoint; i++){
+    PagerSavepoint *p = &pPager->aSavepoint[i];
+    if( p->nOrig>=pgno && 0==sqlite3BitvecTest(p->pInSavepoint, pgno) ){
+      return 1;
     }
-    pPager->stmtOpen = 1;
-    pPager->stmtNRec = 0;
-  }
-  pPager->stmtInUse = 1;
-  return SQLITE_OK;
- 
-stmt_begin_failed:
-  if( pPager->pInStmt ){
-    sqlite3BitvecDestroy(pPager->pInStmt);
-    pPager->pInStmt = 0;
   }
-  return rc;
-}
-SQLITE_PRIVATE int sqlite3PagerStmtBegin(Pager *pPager){
-  int rc;
-  pagerEnter(pPager);
-  rc = pagerStmtBegin(pPager);
-  pagerLeave(pPager);
-  return rc;
+  return 0;
 }
 
 /*
-** Commit a statement.
+** Return true if the page is already in the journal file.
 */
-SQLITE_PRIVATE int sqlite3PagerStmtCommit(Pager *pPager){
-  pagerEnter(pPager);
-  if( pPager->stmtInUse ){
-    PgHdr *pPg, *pNext;
-    PAGERTRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
-    if( !MEMDB ){
-      /* sqlite3OsTruncate(pPager->stfd, 0); */
-      sqlite3BitvecDestroy(pPager->pInStmt);
-      pPager->pInStmt = 0;
-    }else{
-      for(pPg=pPager->pStmt; pPg; pPg=pNext){
-        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
-        pNext = pHist->pNextStmt;
-        assert( pHist->inStmt );
-        pHist->inStmt = 0;
-        pHist->pPrevStmt = pHist->pNextStmt = 0;
-        sqlite3_free(pHist->pStmt);
-        pHist->pStmt = 0;
-      }
-    }
-    pPager->stmtNRec = 0;
-    pPager->stmtInUse = 0;
-    pPager->pStmt = 0;
-  }
-  pPager->stmtAutoopen = 0;
-  pagerLeave(pPager);
-  return SQLITE_OK;
+static int pageInJournal(PgHdr *pPg){
+  return sqlite3BitvecTest(pPg->pPager->pInJournal, pPg->pgno);
 }
 
 /*
-** Rollback a statement.
+** Read a 32-bit integer from the given file descriptor.  Store the integer
+** that is read in *pRes.  Return SQLITE_OK if everything worked, or an
+** error code is something goes wrong.
+**
+** All values are stored on disk as big-endian.
 */
-SQLITE_PRIVATE int sqlite3PagerStmtRollback(Pager *pPager){
-  int rc;
-  pagerEnter(pPager);
-  if( pPager->stmtInUse ){
-    PAGERTRACE2("STMT-ROLLBACK %d\n", PAGERID(pPager));
-    if( MEMDB ){
-      PgHdr *pPg;
-      PgHistory *pHist;
-      for(pPg=pPager->pStmt; pPg; pPg=pHist->pNextStmt){
-        pHist = PGHDR_TO_HIST(pPg, pPager);
-        if( pHist->pStmt ){
-          memcpy(PGHDR_TO_DATA(pPg), pHist->pStmt, pPager->pageSize);
-          sqlite3_free(pHist->pStmt);
-          pHist->pStmt = 0;
-        }
-      }
-      pPager->dbSize = pPager->stmtSize;
-      pager_truncate_cache(pPager);
-      rc = SQLITE_OK;
-    }else{
-      rc = pager_stmt_playback(pPager);
-    }
-    sqlite3PagerStmtCommit(pPager);
-  }else{
-    rc = SQLITE_OK;
+static int read32bits(sqlite3_file *fd, i64 offset, u32 *pRes){
+  unsigned char ac[4];
+  int rc = sqlite3OsRead(fd, ac, sizeof(ac), offset);
+  if( rc==SQLITE_OK ){
+    *pRes = sqlite3Get4byte(ac);
   }
-  pPager->stmtAutoopen = 0;
-  pagerLeave(pPager);
   return rc;
 }
 
 /*
-** Return the full pathname of the database file.
+** Write a 32-bit integer into a string buffer in big-endian byte order.
 */
-SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager *pPager){
-  return pPager->zFilename;
-}
+#define put32bits(A,B)  sqlite3Put4byte((u8*)A,B)
 
 /*
-** Return the VFS structure for the pager.
+** Write a 32-bit integer into the given file descriptor.  Return SQLITE_OK
+** on success or an error code is something goes wrong.
 */
-SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager *pPager){
-  return pPager->pVfs;
+static int write32bits(sqlite3_file *fd, i64 offset, u32 val){
+  char ac[4];
+  put32bits(ac, val);
+  return sqlite3OsWrite(fd, ac, 4, offset);
 }
 
 /*
-** Return the file handle for the database file associated
-** with the pager.  This might return NULL if the file has
-** not yet been opened.
+** The argument to this macro is a file descriptor (type sqlite3_file*).
+** Return 0 if it is not open, or non-zero (but not 1) if it is.
+**
+** This is so that expressions can be written as:
+**
+**   if( isOpen(pPager->jfd) ){ ...
+**
+** instead of
+**
+**   if( pPager->jfd->pMethods ){ ...
 */
-SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager *pPager){
-  return pPager->fd;
+#define isOpen(pFd) ((pFd)->pMethods)
+
+/*
+** If file pFd is open, call sqlite3OsUnlock() on it.
+*/
+static int osUnlock(sqlite3_file *pFd, int eLock){
+  if( !isOpen(pFd) ){
+    return SQLITE_OK;
+  }
+  return sqlite3OsUnlock(pFd, eLock);
 }
 
 /*
-** Return the directory of the database file.
+** This function determines whether or not the atomic-write optimization
+** can be used with this pager. The optimization can be used if:
+**
+**  (a) the value returned by OsDeviceCharacteristics() indicates that
+**      a database page may be written atomically, and
+**  (b) the value returned by OsSectorSize() is less than or equal
+**      to the page size.
+**
+** The optimization is also always enabled for temporary files. It is
+** an error to call this function if pPager is opened on an in-memory
+** database.
+**
+** If the optimization cannot be used, 0 is returned. If it can be used,
+** then the value returned is the size of the journal file when it
+** contains rollback data for exactly one page.
 */
-SQLITE_PRIVATE const char *sqlite3PagerDirname(Pager *pPager){
-  return pPager->zDirectory;
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+static int jrnlBufferSize(Pager *pPager){
+  assert( !MEMDB );
+  if( !pPager->tempFile ){
+    int dc;                           /* Device characteristics */
+    int nSector;                      /* Sector size */
+    int szPage;                       /* Page size */
+
+    assert( isOpen(pPager->fd) );
+    dc = sqlite3OsDeviceCharacteristics(pPager->fd);
+    nSector = pPager->sectorSize;
+    szPage = pPager->pageSize;
+
+    assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+    assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+    if( 0==(dc&(SQLITE_IOCAP_ATOMIC|(szPage>>8)) || nSector>szPage) ){
+      return 0;
+    }
+  }
+
+  return JOURNAL_HDR_SZ(pPager) + JOURNAL_PG_SZ(pPager);
 }
+#endif
 
 /*
-** Return the full pathname of the journal file.
+** If SQLITE_CHECK_PAGES is defined then we do some sanity checking
+** on the cache using a hash function.  This is used for testing
+** and debugging only.
 */
-SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager *pPager){
-  return pPager->zJournal;
+#ifdef SQLITE_CHECK_PAGES
+/*
+** Return a 32-bit hash of the page data for pPage.
+*/
+static u32 pager_datahash(int nByte, unsigned char *pData){
+  u32 hash = 0;
+  int i;
+  for(i=0; i<nByte; i++){
+    hash = (hash*1039) + pData[i];
+  }
+  return hash;
+}
+static u32 pager_pagehash(PgHdr *pPage){
+  return pager_datahash(pPage->pPager->pageSize, (unsigned char *)pPage->pData);
+}
+static void pager_set_pagehash(PgHdr *pPage){
+  pPage->pageHash = pager_pagehash(pPage);
 }
 
 /*
-** Return true if fsync() calls are disabled for this pager.  Return FALSE
-** if fsync()s are executed normally.
+** The CHECK_PAGE macro takes a PgHdr* as an argument. If SQLITE_CHECK_PAGES
+** is defined, and NDEBUG is not defined, an assert() statement checks
+** that the page is either dirty or still matches the calculated page-hash.
 */
-SQLITE_PRIVATE int sqlite3PagerNosync(Pager *pPager){
-  return pPager->noSync;
+#define CHECK_PAGE(x) checkPage(x)
+static void checkPage(PgHdr *pPg){
+  Pager *pPager = pPg->pPager;
+  assert( !pPg->pageHash || pPager->errCode
+      || (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
 }
 
-#ifdef SQLITE_HAS_CODEC
+#else
+#define pager_datahash(X,Y)  0
+#define pager_pagehash(X)  0
+#define CHECK_PAGE(x)
+#endif  /* SQLITE_CHECK_PAGES */
+
 /*
-** Set the codec for this pager
+** When this is called the journal file for pager pPager must be open.
+** This function attempts to read a master journal file name from the 
+** end of the file and, if successful, copies it into memory supplied 
+** by the caller. See comments above writeMasterJournal() for the format
+** used to store a master journal file name at the end of a journal file.
+**
+** zMaster must point to a buffer of at least nMaster bytes allocated by
+** the caller. This should be sqlite3_vfs.mxPathname+1 (to ensure there is
+** enough space to write the master journal name). If the master journal
+** name in the journal is longer than nMaster bytes (including a
+** nul-terminator), then this is handled as if no master journal name
+** were present in the journal.
+**
+** If a master journal file name is present at the end of the journal
+** file, then it is copied into the buffer pointed to by zMaster. A
+** nul-terminator byte is appended to the buffer following the master
+** journal file name.
+**
+** If it is determined that no master journal file name is present 
+** zMaster[0] is set to 0 and SQLITE_OK returned.
+**
+** If an error occurs while reading from the journal file, an SQLite
+** error code is returned.
 */
-SQLITE_PRIVATE void sqlite3PagerSetCodec(
-  Pager *pPager,
-  void *(*xCodec)(void*,void*,Pgno,int),
-  void *pCodecArg
-){
-  pPager->xCodec = xCodec;
-  pPager->pCodecArg = pCodecArg;
+static int readMasterJournal(sqlite3_file *pJrnl, char *zMaster, u32 nMaster){
+  int rc;                    /* Return code */
+  u32 len;                   /* Length in bytes of master journal name */
+  i64 szJ;                   /* Total size in bytes of journal file pJrnl */
+  u32 cksum;                 /* MJ checksum value read from journal */
+  u32 u;                     /* Unsigned loop counter */
+  unsigned char aMagic[8];   /* A buffer to hold the magic header */
+  zMaster[0] = '\0';
+
+  if( SQLITE_OK!=(rc = sqlite3OsFileSize(pJrnl, &szJ))
+   || szJ<16
+   || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-16, &len))
+   || len>=nMaster 
+   || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-12, &cksum))
+   || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8))
+   || memcmp(aMagic, aJournalMagic, 8)
+   || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, zMaster, len, szJ-16-len))
+  ){
+    return rc;
+  }
+
+  /* See if the checksum matches the master journal name */
+  for(u=0; u<len; u++){
+    cksum -= zMaster[u];
+  }
+  if( cksum ){
+    /* If the checksum doesn't add up, then one or more of the disk sectors
+    ** containing the master journal filename is corrupted. This means
+    ** definitely roll back, so just return SQLITE_OK and report a (nul)
+    ** master-journal filename.
+    */
+    len = 0;
+  }
+  zMaster[len] = '\0';
+   
+  return SQLITE_OK;
 }
-#endif
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Move the page pPg to location pgno in the file.
+** Return the offset of the sector boundary at or immediately 
+** following the value in pPager->journalOff, assuming a sector 
+** size of pPager->sectorSize bytes.
 **
-** There must be no references to the page previously located at
-** pgno (which we call pPgOld) though that page is allowed to be
-** in cache.  If the page previous located at pgno is not already
-** in the rollback journal, it is not put there by by this routine.
+** i.e for a sector size of 512:
 **
-** References to the page pPg remain valid. Updating any
-** meta-data associated with pPg (i.e. data stored in the nExtra bytes
-** allocated along with the page) is the responsibility of the caller.
+**   Pager.journalOff          Return value
+**   ---------------------------------------
+**   0                         0
+**   512                       512
+**   100                       512
+**   2000                      2048
+** 
+*/
+static i64 journalHdrOffset(Pager *pPager){
+  i64 offset = 0;
+  i64 c = pPager->journalOff;
+  if( c ){
+    offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
+  }
+  assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
+  assert( offset>=c );
+  assert( (offset-c)<JOURNAL_HDR_SZ(pPager) );
+  return offset;
+}
+
+/*
+** The journal file must be open when this function is called.
 **
-** A transaction must be active when this routine is called. It used to be
-** required that a statement transaction was not active, but this restriction
-** has been removed (CREATE INDEX needs to move a page when a statement
-** transaction is active).
+** This function is a no-op if the journal file has not been written to
+** within the current transaction (i.e. if Pager.journalOff==0).
+**
+** If doTruncate is non-zero or the Pager.journalSizeLimit variable is
+** set to 0, then truncate the journal file to zero bytes in size. Otherwise,
+** zero the 28-byte header at the start of the journal file. In either case, 
+** if the pager is not in no-sync mode, sync the journal file immediately 
+** after writing or truncating it.
+**
+** If Pager.journalSizeLimit is set to a positive, non-zero value, and
+** following the truncation or zeroing described above the size of the 
+** journal file in bytes is larger than this value, then truncate the
+** journal file to Pager.journalSizeLimit bytes. The journal file does
+** not need to be synced following this operation.
+**
+** If an IO error occurs, abandon processing and return the IO error code.
+** Otherwise, return SQLITE_OK.
 */
-SQLITE_PRIVATE int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno){
-  PgHdr *pPgOld;  /* The page being overwritten. */
-  int h;
-  Pgno needSyncPgno = 0;
+static int zeroJournalHdr(Pager *pPager, int doTruncate){
+  int rc = SQLITE_OK;                               /* Return code */
+  assert( isOpen(pPager->jfd) );
+  if( pPager->journalOff ){
+    const i64 iLimit = pPager->journalSizeLimit;    /* Local cache of jsl */
 
-  pagerEnter(pPager);
-  assert( pPg->nRef>0 );
+    IOTRACE(("JZEROHDR %p\n", pPager))
+    if( doTruncate || iLimit==0 ){
+      rc = sqlite3OsTruncate(pPager->jfd, 0);
+    }else{
+      static const char zeroHdr[28] = {0};
+      rc = sqlite3OsWrite(pPager->jfd, zeroHdr, sizeof(zeroHdr), 0);
+    }
+    if( rc==SQLITE_OK && !pPager->noSync ){
+      rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_DATAONLY|pPager->sync_flags);
+    }
 
-  PAGERTRACE5("MOVE %d page %d (needSync=%d) moves to %d\n", 
-      PAGERID(pPager), pPg->pgno, pPg->needSync, pgno);
-  IOTRACE(("MOVE %p %d %d\n", pPager, pPg->pgno, pgno))
+    /* At this point the transaction is committed but the write lock 
+    ** is still held on the file. If there is a size limit configured for 
+    ** the persistent journal and the journal file currently consumes more
+    ** space than that limit allows for, truncate it now. There is no need
+    ** to sync the file following this operation.
+    */
+    if( rc==SQLITE_OK && iLimit>0 ){
+      i64 sz;
+      rc = sqlite3OsFileSize(pPager->jfd, &sz);
+      if( rc==SQLITE_OK && sz>iLimit ){
+        rc = sqlite3OsTruncate(pPager->jfd, iLimit);
+      }
+    }
+  }
+  return rc;
+}
 
-  pager_get_content(pPg);
-  if( pPg->needSync ){
-    needSyncPgno = pPg->pgno;
-    assert( pPg->inJournal || (int)pgno>pPager->origDbSize );
-    assert( pPg->dirty );
-    assert( pPager->needSync );
+/*
+** The journal file must be open when this routine is called. A journal
+** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
+** current location.
+**
+** The format for the journal header is as follows:
+** - 8 bytes: Magic identifying journal format.
+** - 4 bytes: Number of records in journal, or -1 no-sync mode is on.
+** - 4 bytes: Random number used for page hash.
+** - 4 bytes: Initial database page count.
+** - 4 bytes: Sector size used by the process that wrote this journal.
+** - 4 bytes: Database page size.
+** 
+** Followed by (JOURNAL_HDR_SZ - 28) bytes of unused space.
+*/
+static int writeJournalHdr(Pager *pPager){
+  int rc = SQLITE_OK;                 /* Return code */
+  char *zHeader = pPager->pTmpSpace;  /* Temporary space used to build header */
+  u32 nHeader = pPager->pageSize;     /* Size of buffer pointed to by zHeader */
+  u32 nWrite;                         /* Bytes of header sector written */
+  int ii;                             /* Loop counter */
+
+  assert( isOpen(pPager->jfd) );      /* Journal file must be open. */
+
+  if( nHeader>JOURNAL_HDR_SZ(pPager) ){
+    nHeader = JOURNAL_HDR_SZ(pPager);
   }
 
-  /* Unlink pPg from its hash-chain */
-  unlinkHashChain(pPager, pPg);
+  /* If there are active savepoints and any of them were created 
+  ** since the most recent journal header was written, update the 
+  ** PagerSavepoint.iHdrOffset fields now.
+  */
+  for(ii=0; ii<pPager->nSavepoint; ii++){
+    if( pPager->aSavepoint[ii].iHdrOffset==0 ){
+      pPager->aSavepoint[ii].iHdrOffset = pPager->journalOff;
+    }
+  }
 
-  /* If the cache contains a page with page-number pgno, remove it
-  ** from its hash chain. Also, if the PgHdr.needSync was set for 
-  ** page pgno before the 'move' operation, it needs to be retained 
-  ** for the page moved there.
+  pPager->journalHdr = pPager->journalOff = journalHdrOffset(pPager);
+
+  /* 
+  ** Write the nRec Field - the number of page records that follow this
+  ** journal header. Normally, zero is written to this value at this time.
+  ** After the records are added to the journal (and the journal synced, 
+  ** if in full-sync mode), the zero is overwritten with the true number
+  ** of records (see syncJournal()).
+  **
+  ** A faster alternative is to write 0xFFFFFFFF to the nRec field. When
+  ** reading the journal this value tells SQLite to assume that the
+  ** rest of the journal file contains valid page records. This assumption
+  ** is dangerous, as if a failure occurred whilst writing to the journal
+  ** file it may contain some garbage data. There are two scenarios
+  ** where this risk can be ignored:
+  **
+  **   * When the pager is in no-sync mode. Corruption can follow a
+  **     power failure in this case anyway.
+  **
+  **   * When the SQLITE_IOCAP_SAFE_APPEND flag is set. This guarantees
+  **     that garbage data is never appended to the journal file.
   */
-  pPg->needSync = 0;
-  pPgOld = pager_lookup(pPager, pgno);
-  if( pPgOld ){
-    assert( pPgOld->nRef==0 );
-    unlinkHashChain(pPager, pPgOld);
-    makeClean(pPgOld);
-    pPg->needSync = pPgOld->needSync;
+  assert( isOpen(pPager->fd) || pPager->noSync );
+  if( (pPager->noSync) || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
+   || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
+  ){
+    memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+    put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
   }else{
-    pPg->needSync = 0;
+    memset(zHeader, 0, sizeof(aJournalMagic)+4);
   }
-  pPg->inJournal = sqlite3BitvecTest(pPager->pInJournal, pgno);
 
-  /* Change the page number for pPg and insert it into the new hash-chain. */
-  assert( pgno!=0 );
-  pPg->pgno = pgno;
-  h = pgno & (pPager->nHash-1);
-  if( pPager->aHash[h] ){
-    assert( pPager->aHash[h]->pPrevHash==0 );
-    pPager->aHash[h]->pPrevHash = pPg;
-  }
-  pPg->pNextHash = pPager->aHash[h];
-  pPager->aHash[h] = pPg;
-  pPg->pPrevHash = 0;
-
-  makeDirty(pPg);
-  pPager->dirtyCache = 1;
-  pPager->dbModified = 1;
+  /* The random check-hash initialiser */ 
+  sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
+  put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
+  /* The initial database size */
+  put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbOrigSize);
+  /* The assumed sector size for this process */
+  put32bits(&zHeader[sizeof(aJournalMagic)+12], pPager->sectorSize);
 
-  if( needSyncPgno ){
-    /* If needSyncPgno is non-zero, then the journal file needs to be 
-    ** sync()ed before any data is written to database file page needSyncPgno.
-    ** Currently, no such page exists in the page-cache and the 
-    ** Pager.pInJournal bit has been set. This needs to be remedied by loading
-    ** the page into the pager-cache and setting the PgHdr.needSync flag.
-    **
-    ** If the attempt to load the page into the page-cache fails, (due
-    ** to a malloc() or IO failure), clear the bit in the pInJournal[]
-    ** array. Otherwise, if the page is loaded and written again in
-    ** this transaction, it may be written to the database file before
-    ** it is synced into the journal file. This way, it may end up in
-    ** the journal file twice, but that is not a problem.
-    **
-    ** The sqlite3PagerGet() call may cause the journal to sync. So make
-    ** sure the Pager.needSync flag is set too.
-    */
-    int rc;
-    PgHdr *pPgHdr;
-    assert( pPager->needSync );
-    rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
-    if( rc!=SQLITE_OK ){
-      if( pPager->pInJournal && (int)needSyncPgno<=pPager->origDbSize ){
-        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno);
-      }
-      pagerLeave(pPager);
+  /* The page size */
+  put32bits(&zHeader[sizeof(aJournalMagic)+16], pPager->pageSize);
+
+  /* Initializing the tail of the buffer is not necessary.  Everything
+  ** works find if the following memset() is omitted.  But initializing
+  ** the memory prevents valgrind from complaining, so we are willing to
+  ** take the performance hit.
+  */
+  memset(&zHeader[sizeof(aJournalMagic)+20], 0,
+         nHeader-(sizeof(aJournalMagic)+20));
+
+  /* In theory, it is only necessary to write the 28 bytes that the 
+  ** journal header consumes to the journal file here. Then increment the 
+  ** Pager.journalOff variable by JOURNAL_HDR_SZ so that the next 
+  ** record is written to the following sector (leaving a gap in the file
+  ** that will be implicitly filled in by the OS).
+  **
+  ** However it has been discovered that on some systems this pattern can 
+  ** be significantly slower than contiguously writing data to the file,
+  ** even if that means explicitly writing data to the block of 
+  ** (JOURNAL_HDR_SZ - 28) bytes that will not be used. So that is what
+  ** is done. 
+  **
+  ** The loop is required here in case the sector-size is larger than the 
+  ** database page size. Since the zHeader buffer is only Pager.pageSize
+  ** bytes in size, more than one call to sqlite3OsWrite() may be required
+  ** to populate the entire journal header sector.
+  */ 
+  for(nWrite=0; rc==SQLITE_OK&&nWrite<JOURNAL_HDR_SZ(pPager); nWrite+=nHeader){
+    IOTRACE(("JHDR %p %lld %d\n", pPager, pPager->journalHdr, nHeader))
+    rc = sqlite3OsWrite(pPager->jfd, zHeader, nHeader, pPager->journalOff);
+    pPager->journalOff += nHeader;
+  }
+
+  return rc;
+}
+
+/*
+** The journal file must be open when this is called. A journal header file
+** (JOURNAL_HDR_SZ bytes) is read from the current location in the journal
+** file. The current location in the journal file is given by
+** pPager->journalOff. See comments above function writeJournalHdr() for
+** a description of the journal header format.
+**
+** If the header is read successfully, *pNRec is set to the number of
+** page records following this header and *pDbSize is set to the size of the
+** database before the transaction began, in pages. Also, pPager->cksumInit
+** is set to the value read from the journal header. SQLITE_OK is returned
+** in this case.
+**
+** If the journal header file appears to be corrupted, SQLITE_DONE is
+** returned and *pNRec and *PDbSize are undefined.  If JOURNAL_HDR_SZ bytes
+** cannot be read from the journal file an error code is returned.
+*/
+static int readJournalHdr(
+  Pager *pPager,               /* Pager object */
+  int isHot,
+  i64 journalSize,             /* Size of the open journal file in bytes */
+  u32 *pNRec,                  /* OUT: Value read from the nRec field */
+  u32 *pDbSize                 /* OUT: Value of original database size field */
+){
+  int rc;                      /* Return code */
+  unsigned char aMagic[8];     /* A buffer to hold the magic header */
+  i64 iHdrOff;                 /* Offset of journal header being read */
+
+  assert( isOpen(pPager->jfd) );      /* Journal file must be open. */
+
+  /* Advance Pager.journalOff to the start of the next sector. If the
+  ** journal file is too small for there to be a header stored at this
+  ** point, return SQLITE_DONE.
+  */
+  pPager->journalOff = journalHdrOffset(pPager);
+  if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
+    return SQLITE_DONE;
+  }
+  iHdrOff = pPager->journalOff;
+
+  /* Read in the first 8 bytes of the journal header. If they do not match
+  ** the  magic string found at the start of each journal header, return
+  ** SQLITE_DONE. If an IO error occurs, return an error code. Otherwise,
+  ** proceed.
+  */
+  if( isHot || iHdrOff!=pPager->journalHdr ){
+    rc = sqlite3OsRead(pPager->jfd, aMagic, sizeof(aMagic), iHdrOff);
+    if( rc ){
       return rc;
     }
-    pPager->needSync = 1;
-    pPgHdr->needSync = 1;
-    pPgHdr->inJournal = 1;
-    makeDirty(pPgHdr);
-    sqlite3PagerUnref(pPgHdr);
+    if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
+      return SQLITE_DONE;
+    }
   }
 
-  pagerLeave(pPager);
-  return SQLITE_OK;
+  /* Read the first three 32-bit fields of the journal header: The nRec
+  ** field, the checksum-initializer and the database size at the start
+  ** of the transaction. Return an error code if anything goes wrong.
+  */
+  if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+8, pNRec))
+   || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+12, &pPager->cksumInit))
+   || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+16, pDbSize))
+  ){
+    return rc;
+  }
+
+  if( pPager->journalOff==0 ){
+    u32 iPageSize;               /* Page-size field of journal header */
+    u32 iSectorSize;             /* Sector-size field of journal header */
+    u16 iPageSize16;             /* Copy of iPageSize in 16-bit variable */
+
+    /* Read the page-size and sector-size journal header fields. */
+    if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+20, &iSectorSize))
+     || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+24, &iPageSize))
+    ){
+      return rc;
+    }
+
+    /* Check that the values read from the page-size and sector-size fields
+    ** are within range. To be 'in range', both values need to be a power
+    ** of two greater than or equal to 512, and not greater than their 
+    ** respective compile time maximum limits.
+    */
+    if( iPageSize<512                  || iSectorSize<512
+     || iPageSize>SQLITE_MAX_PAGE_SIZE || iSectorSize>MAX_SECTOR_SIZE
+     || ((iPageSize-1)&iPageSize)!=0   || ((iSectorSize-1)&iSectorSize)!=0 
+    ){
+      /* If the either the page-size or sector-size in the journal-header is 
+      ** invalid, then the process that wrote the journal-header must have 
+      ** crashed before the header was synced. In this case stop reading 
+      ** the journal file here.
+      */
+      return SQLITE_DONE;
+    }
+
+    /* Update the page-size to match the value read from the journal. 
+    ** Use a testcase() macro to make sure that malloc failure within 
+    ** PagerSetPagesize() is tested.
+    */
+    iPageSize16 = (u16)iPageSize;
+    rc = sqlite3PagerSetPagesize(pPager, &iPageSize16, -1);
+    testcase( rc!=SQLITE_OK );
+    assert( rc!=SQLITE_OK || iPageSize16==(u16)iPageSize );
+
+    /* Update the assumed sector-size to match the value used by 
+    ** the process that created this journal. If this journal was
+    ** created by a process other than this one, then this routine
+    ** is being called from within pager_playback(). The local value
+    ** of Pager.sectorSize is restored at the end of that routine.
+    */
+    pPager->sectorSize = iSectorSize;
+  }
+
+  pPager->journalOff += JOURNAL_HDR_SZ(pPager);
+  return rc;
 }
-#endif
+
 
 /*
-** Return a pointer to the data for the specified page.
+** Write the supplied master journal name into the journal file for pager
+** pPager at the current location. The master journal name must be the last
+** thing written to a journal file. If the pager is in full-sync mode, the
+** journal file descriptor is advanced to the next sector boundary before
+** anything is written. The format is:
+**
+**   + 4 bytes: PAGER_MJ_PGNO.
+**   + N bytes: Master journal filename in utf-8.
+**   + 4 bytes: N (length of master journal name in bytes, no nul-terminator).
+**   + 4 bytes: Master journal name checksum.
+**   + 8 bytes: aJournalMagic[].
+**
+** The master journal page checksum is the sum of the bytes in the master
+** journal name, where each byte is interpreted as a signed 8-bit integer.
+**
+** If zMaster is a NULL pointer (occurs for a single database transaction), 
+** this call is a no-op.
 */
-SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *pPg){
-  return PGHDR_TO_DATA(pPg);
+static int writeMasterJournal(Pager *pPager, const char *zMaster){
+  int rc;                          /* Return code */
+  int nMaster;                     /* Length of string zMaster */
+  i64 iHdrOff;                     /* Offset of header in journal file */
+  i64 jrnlSize;                    /* Size of journal file on disk */
+  u32 cksum = 0;                   /* Checksum of string zMaster */
+
+  if( !zMaster || pPager->setMaster
+   || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
+   || pPager->journalMode==PAGER_JOURNALMODE_OFF 
+  ){
+    return SQLITE_OK;
+  }
+  pPager->setMaster = 1;
+  assert( isOpen(pPager->jfd) );
+
+  /* Calculate the length in bytes and the checksum of zMaster */
+  for(nMaster=0; zMaster[nMaster]; nMaster++){
+    cksum += zMaster[nMaster];
+  }
+
+  /* If in full-sync mode, advance to the next disk sector before writing
+  ** the master journal name. This is in case the previous page written to
+  ** the journal has already been synced.
+  */
+  if( pPager->fullSync ){
+    pPager->journalOff = journalHdrOffset(pPager);
+  }
+  iHdrOff = pPager->journalOff;
+
+  /* Write the master journal data to the end of the journal file. If
+  ** an error occurs, return the error code to the caller.
+  */
+  if( (0 != (rc = write32bits(pPager->jfd, iHdrOff, PAGER_MJ_PGNO(pPager))))
+   || (0 != (rc = sqlite3OsWrite(pPager->jfd, zMaster, nMaster, iHdrOff+4)))
+   || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster, nMaster)))
+   || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster+4, cksum)))
+   || (0 != (rc = sqlite3OsWrite(pPager->jfd, aJournalMagic, 8, iHdrOff+4+nMaster+8)))
+  ){
+    return rc;
+  }
+  pPager->journalOff += (nMaster+20);
+  pPager->needSync = !pPager->noSync;
+
+  /* If the pager is in peristent-journal mode, then the physical 
+  ** journal-file may extend past the end of the master-journal name
+  ** and 8 bytes of magic data just written to the file. This is 
+  ** dangerous because the code to rollback a hot-journal file
+  ** will not be able to find the master-journal name to determine 
+  ** whether or not the journal is hot. 
+  **
+  ** Easiest thing to do in this scenario is to truncate the journal 
+  ** file to the required size.
+  */ 
+  if( SQLITE_OK==(rc = sqlite3OsFileSize(pPager->jfd, &jrnlSize))
+   && jrnlSize>pPager->journalOff
+  ){
+    rc = sqlite3OsTruncate(pPager->jfd, pPager->journalOff);
+  }
+  return rc;
 }
 
 /*
-** Return a pointer to the Pager.nExtra bytes of "extra" space 
-** allocated along with the specified page.
+** Find a page in the hash table given its page number. Return
+** a pointer to the page or NULL if the requested page is not 
+** already in memory.
 */
-SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *pPg){
-  Pager *pPager = pPg->pPager;
-  return (pPager?PGHDR_TO_EXTRA(pPg, pPager):0);
+static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
+  PgHdr *p;                         /* Return value */
+
+  /* It is not possible for a call to PcacheFetch() with createFlag==0 to
+  ** fail, since no attempt to allocate dynamic memory will be made.
+  */
+  (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &p);
+  return p;
 }
 
 /*
-** Get/set the locking-mode for this pager. Parameter eMode must be one
-** of PAGER_LOCKINGMODE_QUERY, PAGER_LOCKINGMODE_NORMAL or 
-** PAGER_LOCKINGMODE_EXCLUSIVE. If the parameter is not _QUERY, then
-** the locking-mode is set to the value specified.
+** Unless the pager is in error-state, discard all in-memory pages. If
+** the pager is in error-state, then this call is a no-op.
 **
-** The returned value is either PAGER_LOCKINGMODE_NORMAL or
-** PAGER_LOCKINGMODE_EXCLUSIVE, indicating the current (possibly updated)
-** locking-mode.
+** TODO: Why can we not reset the pager while in error state?
 */
-SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *pPager, int eMode){
-  assert( eMode==PAGER_LOCKINGMODE_QUERY
-            || eMode==PAGER_LOCKINGMODE_NORMAL
-            || eMode==PAGER_LOCKINGMODE_EXCLUSIVE );
-  assert( PAGER_LOCKINGMODE_QUERY<0 );
-  assert( PAGER_LOCKINGMODE_NORMAL>=0 && PAGER_LOCKINGMODE_EXCLUSIVE>=0 );
-  if( eMode>=0 && !pPager->tempFile ){
-    pPager->exclusiveMode = eMode;
+static void pager_reset(Pager *pPager){
+  if( SQLITE_OK==pPager->errCode ){
+    sqlite3BackupRestart(pPager->pBackup);
+    sqlite3PcacheClear(pPager->pPCache);
+    pPager->dbSizeValid = 0;
   }
-  return (int)pPager->exclusiveMode;
 }
 
 /*
-** Get/set the journal-mode for this pager. Parameter eMode must be one
-** of PAGER_JOURNALMODE_QUERY, PAGER_JOURNALMODE_DELETE or 
-** PAGER_JOURNALMODE_PERSIST. If the parameter is not _QUERY, then
-** the journal-mode is set to the value specified.
-**
-** The returned value is either PAGER_JOURNALMODE_DELETE or
-** PAGER_JOURNALMODE_PERSIST, indicating the current (possibly updated)
-** journal-mode.
+** Free all structures in the Pager.aSavepoint[] array and set both
+** Pager.aSavepoint and Pager.nSavepoint to zero. Close the sub-journal
+** if it is open and the pager is not in exclusive mode.
 */
-SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *pPager, int eMode){
-  assert( eMode==PAGER_JOURNALMODE_QUERY
-            || eMode==PAGER_JOURNALMODE_DELETE
-            || eMode==PAGER_JOURNALMODE_PERSIST
-            || eMode==PAGER_JOURNALMODE_OFF );
-  assert( PAGER_JOURNALMODE_QUERY<0 );
-  assert( PAGER_JOURNALMODE_DELETE>=0 && PAGER_JOURNALMODE_PERSIST>=0 );
-  if( eMode>=0 ){
-    pPager->journalMode = eMode;
+static void releaseAllSavepoints(Pager *pPager){
+  int ii;               /* Iterator for looping through Pager.aSavepoint */
+  for(ii=0; ii<pPager->nSavepoint; ii++){
+    sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
   }
-  return (int)pPager->journalMode;
+  if( !pPager->exclusiveMode || sqlite3IsMemJournal(pPager->sjfd) ){
+    sqlite3OsClose(pPager->sjfd);
+  }
+  sqlite3_free(pPager->aSavepoint);
+  pPager->aSavepoint = 0;
+  pPager->nSavepoint = 0;
+  pPager->nSubRec = 0;
 }
 
-#ifdef SQLITE_TEST
 /*
-** Print a listing of all referenced pages and their ref count.
+** Set the bit number pgno in the PagerSavepoint.pInSavepoint 
+** bitvecs of all open savepoints. Return SQLITE_OK if successful
+** or SQLITE_NOMEM if a malloc failure occurs.
 */
-SQLITE_PRIVATE void sqlite3PagerRefdump(Pager *pPager){
-  PgHdr *pPg;
-  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
-    if( pPg->nRef<=0 ) continue;
-    sqlite3DebugPrintf("PAGE %3d addr=%p nRef=%d\n", 
-       pPg->pgno, PGHDR_TO_DATA(pPg), pPg->nRef);
+static int addToSavepointBitvecs(Pager *pPager, Pgno pgno){
+  int ii;                   /* Loop counter */
+  int rc = SQLITE_OK;       /* Result code */
+
+  for(ii=0; ii<pPager->nSavepoint; ii++){
+    PagerSavepoint *p = &pPager->aSavepoint[ii];
+    if( pgno<=p->nOrig ){
+      rc |= sqlite3BitvecSet(p->pInSavepoint, pgno);
+      testcase( rc==SQLITE_NOMEM );
+      assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+    }
   }
+  return rc;
 }
-#endif
-
-#endif /* SQLITE_OMIT_DISKIO */
 
-/************** End of pager.c ***********************************************/
-/************** Begin file btmutex.c *****************************************/
 /*
-** 2007 August 27
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-**
-** $Id: btmutex.c,v 1.9 2008/01/23 12:52:41 drh Exp $
+** Unlock the database file. This function is a no-op if the pager
+** is in exclusive mode.
 **
-** This file contains code used to implement mutexes on Btree objects.
-** This code really belongs in btree.c.  But btree.c is getting too
-** big and we want to break it down some.  This packaged seemed like
-** a good breakout.
+** If the pager is currently in error state, discard the contents of 
+** the cache and reset the Pager structure internal state. If there is
+** an open journal-file, then the next time a shared-lock is obtained
+** on the pager file (by this or any other process), it will be
+** treated as a hot-journal and rolled back.
 */
-/************** Include btreeInt.h in the middle of btmutex.c ****************/
-/************** Begin file btreeInt.h ****************************************/
+static void pager_unlock(Pager *pPager){
+  if( !pPager->exclusiveMode ){
+    int rc;                      /* Return code */
+
+    /* Always close the journal file when dropping the database lock.
+    ** Otherwise, another connection with journal_mode=delete might
+    ** delete the file out from under us.
+    */
+    sqlite3OsClose(pPager->jfd);
+    sqlite3BitvecDestroy(pPager->pInJournal);
+    pPager->pInJournal = 0;
+    releaseAllSavepoints(pPager);
+
+    /* If the file is unlocked, somebody else might change it. The
+    ** values stored in Pager.dbSize etc. might become invalid if
+    ** this happens. TODO: Really, this doesn't need to be cleared
+    ** until the change-counter check fails in PagerSharedLock().
+    */
+    pPager->dbSizeValid = 0;
+
+    rc = osUnlock(pPager->fd, NO_LOCK);
+    if( rc ){
+      pPager->errCode = rc;
+    }
+    IOTRACE(("UNLOCK %p\n", pPager))
+
+    /* If Pager.errCode is set, the contents of the pager cache cannot be
+    ** trusted. Now that the pager file is unlocked, the contents of the
+    ** cache can be discarded and the error code safely cleared.
+    */
+    if( pPager->errCode ){
+      if( rc==SQLITE_OK ){
+        pPager->errCode = SQLITE_OK;
+      }
+      pager_reset(pPager);
+    }
+
+    pPager->changeCountDone = 0;
+    pPager->state = PAGER_UNLOCK;
+  }
+}
+
 /*
-** 2004 April 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** $Id: btreeInt.h,v 1.21 2008/04/24 19:15:10 shane Exp $
-**
-** This file implements a external (disk-based) database using BTrees.
-** For a detailed discussion of BTrees, refer to
-**
-**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
-**     "Sorting And Searching", pages 473-480. Addison-Wesley
-**     Publishing Company, Reading, Massachusetts.
-**
-** The basic idea is that each page of the file contains N database
-** entries and N+1 pointers to subpages.
-**
-**   ----------------------------------------------------------------
-**   |  Ptr(0) | Key(0) | Ptr(1) | Key(1) | ... | Key(N-1) | Ptr(N) |
-**   ----------------------------------------------------------------
-**
-** All of the keys on the page that Ptr(0) points to have values less
-** than Key(0).  All of the keys on page Ptr(1) and its subpages have
-** values greater than Key(0) and less than Key(1).  All of the keys
-** on Ptr(N) and its subpages have values greater than Key(N-1).  And
-** so forth.
-**
-** Finding a particular key requires reading O(log(M)) pages from the 
-** disk where M is the number of entries in the tree.
-**
-** In this implementation, a single file can hold one or more separate 
-** BTrees.  Each BTree is identified by the index of its root page.  The
-** key and data for any entry are combined to form the "payload".  A
-** fixed amount of payload can be carried directly on the database
-** page.  If the payload is larger than the preset amount then surplus
-** bytes are stored on overflow pages.  The payload for an entry
-** and the preceding pointer are combined to form a "Cell".  Each 
-** page has a small header which contains the Ptr(N) pointer and other
-** information such as the size of key and data.
+** This function should be called when an IOERR, CORRUPT or FULL error
+** may have occurred. The first argument is a pointer to the pager 
+** structure, the second the error-code about to be returned by a pager 
+** API function. The value returned is a copy of the second argument 
+** to this function. 
 **
-** FORMAT DETAILS
+** If the second argument is SQLITE_IOERR, SQLITE_CORRUPT, or SQLITE_FULL
+** the error becomes persistent. Until the persisten error is cleared,
+** subsequent API calls on this Pager will immediately return the same 
+** error code.
 **
-** The file is divided into pages.  The first page is called page 1,
-** the second is page 2, and so forth.  A page number of zero indicates
-** "no such page".  The page size can be anything between 512 and 65536.
-** Each page can be either a btree page, a freelist page or an overflow
-** page.
+** A persistent error indicates that the contents of the pager-cache 
+** cannot be trusted. This state can be cleared by completely discarding 
+** the contents of the pager-cache. If a transaction was active when
+** the persistent error occurred, then the rollback journal may need
+** to be replayed to restore the contents of the database file (as if
+** it were a hot-journal).
+*/
+static int pager_error(Pager *pPager, int rc){
+  int rc2 = rc & 0xff;
+  assert( rc==SQLITE_OK || !MEMDB );
+  assert(
+       pPager->errCode==SQLITE_FULL ||
+       pPager->errCode==SQLITE_OK ||
+       (pPager->errCode & 0xff)==SQLITE_IOERR
+  );
+  if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
+    pPager->errCode = rc;
+  }
+  return rc;
+}
+
+/*
+** Execute a rollback if a transaction is active and unlock the 
+** database file. 
 **
-** The first page is always a btree page.  The first 100 bytes of the first
-** page contain a special header (the "file header") that describes the file.
-** The format of the file header is as follows:
+** If the pager has already entered the error state, do not attempt 
+** the rollback at this time. Instead, pager_unlock() is called. The
+** call to pager_unlock() will discard all in-memory pages, unlock
+** the database file and clear the error state. If this means that
+** there is a hot-journal left in the file-system, the next connection
+** to obtain a shared lock on the pager (which may be this one) will
+** roll it back.
 **
-**   OFFSET   SIZE    DESCRIPTION
-**      0      16     Header string: "SQLite format 3\000"
-**     16       2     Page size in bytes.  
-**     18       1     File format write version
-**     19       1     File format read version
-**     20       1     Bytes of unused space at the end of each page
-**     21       1     Max embedded payload fraction
-**     22       1     Min embedded payload fraction
-**     23       1     Min leaf payload fraction
-**     24       4     File change counter
-**     28       4     Reserved for future use
-**     32       4     First freelist page
-**     36       4     Number of freelist pages in the file
-**     40      60     15 4-byte meta values passed to higher layers
-**
-** All of the integer values are big-endian (most significant byte first).
-**
-** The file change counter is incremented when the database is changed
-** This counter allows other processes to know when the file has changed
-** and thus when they need to flush their cache.
-**
-** The max embedded payload fraction is the amount of the total usable
-** space in a page that can be consumed by a single cell for standard
-** B-tree (non-LEAFDATA) tables.  A value of 255 means 100%.  The default
-** is to limit the maximum cell size so that at least 4 cells will fit
-** on one page.  Thus the default max embedded payload fraction is 64.
-**
-** If the payload for a cell is larger than the max payload, then extra
-** payload is spilled to overflow pages.  Once an overflow page is allocated,
-** as many bytes as possible are moved into the overflow pages without letting
-** the cell size drop below the min embedded payload fraction.
-**
-** The min leaf payload fraction is like the min embedded payload fraction
-** except that it applies to leaf nodes in a LEAFDATA tree.  The maximum
-** payload fraction for a LEAFDATA tree is always 100% (or 255) and it
-** not specified in the header.
-**
-** Each btree pages is divided into three sections:  The header, the
-** cell pointer array, and the cell content area.  Page 1 also has a 100-byte
-** file header that occurs before the page header.
+** If the pager has not already entered the error state, but an IO or
+** malloc error occurs during a rollback, then this will itself cause 
+** the pager to enter the error state. Which will be cleared by the
+** call to pager_unlock(), as described above.
+*/
+static void pagerUnlockAndRollback(Pager *pPager){
+  if( pPager->errCode==SQLITE_OK && pPager->state>=PAGER_RESERVED ){
+    sqlite3BeginBenignMalloc();
+    sqlite3PagerRollback(pPager);
+    sqlite3EndBenignMalloc();
+  }
+  pager_unlock(pPager);
+}
+
+/*
+** This routine ends a transaction. A transaction is usually ended by 
+** either a COMMIT or a ROLLBACK operation. This routine may be called 
+** after rollback of a hot-journal, or if an error occurs while opening
+** the journal file or writing the very first journal-header of a
+** database transaction.
+** 
+** If the pager is in PAGER_SHARED or PAGER_UNLOCK state when this
+** routine is called, it is a no-op (returns SQLITE_OK).
+**
+** Otherwise, any active savepoints are released.
+**
+** If the journal file is open, then it is "finalized". Once a journal 
+** file has been finalized it is not possible to use it to roll back a 
+** transaction. Nor will it be considered to be a hot-journal by this
+** or any other database connection. Exactly how a journal is finalized
+** depends on whether or not the pager is running in exclusive mode and
+** the current journal-mode (Pager.journalMode value), as follows:
+**
+**   journalMode==MEMORY
+**     Journal file descriptor is simply closed. This destroys an 
+**     in-memory journal.
+**
+**   journalMode==TRUNCATE
+**     Journal file is truncated to zero bytes in size.
+**
+**   journalMode==PERSIST
+**     The first 28 bytes of the journal file are zeroed. This invalidates
+**     the first journal header in the file, and hence the entire journal
+**     file. An invalid journal file cannot be rolled back.
+**
+**   journalMode==DELETE
+**     The journal file is closed and deleted using sqlite3OsDelete().
+**
+**     If the pager is running in exclusive mode, this method of finalizing
+**     the journal file is never used. Instead, if the journalMode is
+**     DELETE and the pager is in exclusive mode, the method described under
+**     journalMode==PERSIST is used instead.
+**
+** After the journal is finalized, if running in non-exclusive mode, the
+** pager moves to PAGER_SHARED state (and downgrades the lock on the
+** database file accordingly).
+**
+** If the pager is running in exclusive mode and is in PAGER_SYNCED state,
+** it moves to PAGER_EXCLUSIVE. No locks are downgraded when running in
+** exclusive mode.
+**
+** SQLITE_OK is returned if no error occurs. If an error occurs during
+** any of the IO operations to finalize the journal file or unlock the
+** database then the IO error code is returned to the user. If the 
+** operation to finalize the journal file fails, then the code still
+** tries to unlock the database file if not in exclusive mode. If the
+** unlock operation fails as well, then the first error code related
+** to the first error encountered (the journal finalization one) is
+** returned.
+*/
+static int pager_end_transaction(Pager *pPager, int hasMaster){
+  int rc = SQLITE_OK;      /* Error code from journal finalization operation */
+  int rc2 = SQLITE_OK;     /* Error code from db file unlock operation */
+
+  if( pPager->state<PAGER_RESERVED ){
+    return SQLITE_OK;
+  }
+  releaseAllSavepoints(pPager);
+
+  assert( isOpen(pPager->jfd) || pPager->pInJournal==0 );
+  if( isOpen(pPager->jfd) ){
+
+    /* Finalize the journal file. */
+    if( sqlite3IsMemJournal(pPager->jfd) ){
+      assert( pPager->journalMode==PAGER_JOURNALMODE_MEMORY );
+      sqlite3OsClose(pPager->jfd);
+    }else if( pPager->journalMode==PAGER_JOURNALMODE_TRUNCATE ){
+      if( pPager->journalOff==0 ){
+        rc = SQLITE_OK;
+      }else{
+        rc = sqlite3OsTruncate(pPager->jfd, 0);
+      }
+      pPager->journalOff = 0;
+      pPager->journalStarted = 0;
+    }else if( pPager->exclusiveMode 
+     || pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+    ){
+      rc = zeroJournalHdr(pPager, hasMaster);
+      pager_error(pPager, rc);
+      pPager->journalOff = 0;
+      pPager->journalStarted = 0;
+    }else{
+      /* This branch may be executed with Pager.journalMode==MEMORY if
+      ** a hot-journal was just rolled back. In this case the journal
+      ** file should be closed and deleted. If this connection writes to
+      ** the database file, it will do so using an in-memory journal.  */
+      assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE 
+           || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
+      );
+      sqlite3OsClose(pPager->jfd);
+      if( !pPager->tempFile ){
+        rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+      }
+    }
+
+#ifdef SQLITE_CHECK_PAGES
+    sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
+#endif
+
+    sqlite3PcacheCleanAll(pPager->pPCache);
+    sqlite3BitvecDestroy(pPager->pInJournal);
+    pPager->pInJournal = 0;
+    pPager->nRec = 0;
+  }
+
+  if( !pPager->exclusiveMode ){
+    rc2 = osUnlock(pPager->fd, SHARED_LOCK);
+    pPager->state = PAGER_SHARED;
+    pPager->changeCountDone = 0;
+  }else if( pPager->state==PAGER_SYNCED ){
+    pPager->state = PAGER_EXCLUSIVE;
+  }
+  pPager->setMaster = 0;
+  pPager->needSync = 0;
+  pPager->dbModified = 0;
+
+  /* TODO: Is this optimal? Why is the db size invalidated here 
+  ** when the database file is not unlocked? */
+  pPager->dbOrigSize = 0;
+  sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
+  if( !MEMDB ){
+    pPager->dbSizeValid = 0;
+  }
+
+  return (rc==SQLITE_OK?rc2:rc);
+}
+
+/*
+** Parameter aData must point to a buffer of pPager->pageSize bytes
+** of data. Compute and return a checksum based ont the contents of the 
+** page of data and the current value of pPager->cksumInit.
 **
-**      |----------------|
-**      | file header    |   100 bytes.  Page 1 only.
-**      |----------------|
-**      | page header    |   8 bytes for leaves.  12 bytes for interior nodes
-**      |----------------|
-**      | cell pointer   |   |  2 bytes per cell.  Sorted order.
-**      | array          |   |  Grows downward
-**      |                |   v
-**      |----------------|
-**      | unallocated    |
-**      | space          |
-**      |----------------|   ^  Grows upwards
-**      | cell content   |   |  Arbitrary order interspersed with freeblocks.
-**      | area           |   |  and free space fragments.
-**      |----------------|
+** This is not a real checksum. It is really just the sum of the 
+** random initial value (pPager->cksumInit) and every 200th byte
+** of the page data, starting with byte offset (pPager->pageSize%200).
+** Each byte is interpreted as an 8-bit unsigned integer.
 **
-** The page headers looks like this:
+** Changing the formula used to compute this checksum results in an
+** incompatible journal file format.
 **
-**   OFFSET   SIZE     DESCRIPTION
-**      0       1      Flags. 1: intkey, 2: zerodata, 4: leafdata, 8: leaf
-**      1       2      byte offset to the first freeblock
-**      3       2      number of cells on this page
-**      5       2      first byte of the cell content area
-**      7       1      number of fragmented free bytes
-**      8       4      Right child (the Ptr(N) value).  Omitted on leaves.
+** If journal corruption occurs due to a power failure, the most likely 
+** scenario is that one end or the other of the record will be changed. 
+** It is much less likely that the two ends of the journal record will be
+** correct and the middle be corrupt.  Thus, this "checksum" scheme,
+** though fast and simple, catches the mostly likely kind of corruption.
+*/
+static u32 pager_cksum(Pager *pPager, const u8 *aData){
+  u32 cksum = pPager->cksumInit;         /* Checksum value to return */
+  int i = pPager->pageSize-200;          /* Loop counter */
+  while( i>0 ){
+    cksum += aData[i];
+    i -= 200;
+  }
+  return cksum;
+}
+
+/*
+** Read a single page from either the journal file (if isMainJrnl==1) or
+** from the sub-journal (if isMainJrnl==0) and playback that page.
+** The page begins at offset *pOffset into the file. The *pOffset
+** value is increased to the start of the next page in the journal.
 **
-** The flags define the format of this btree page.  The leaf flag means that
-** this page has no children.  The zerodata flag means that this page carries
-** only keys and no data.  The intkey flag means that the key is a integer
-** which is stored in the key size entry of the cell header rather than in
-** the payload area.
+** The isMainJrnl flag is true if this is the main rollback journal and
+** false for the statement journal.  The main rollback journal uses
+** checksums - the statement journal does not.
 **
-** The cell pointer array begins on the first byte after the page header.
-** The cell pointer array contains zero or more 2-byte numbers which are
-** offsets from the beginning of the page to the cell content in the cell
-** content area.  The cell pointers occur in sorted order.  The system strives
-** to keep free space after the last cell pointer so that new cells can
-** be easily added without having to defragment the page.
+** If the page number of the page record read from the (sub-)journal file
+** is greater than the current value of Pager.dbSize, then playback is
+** skipped and SQLITE_OK is returned.
 **
-** Cell content is stored at the very end of the page and grows toward the
-** beginning of the page.
+** If pDone is not NULL, then it is a record of pages that have already
+** been played back.  If the page at *pOffset has already been played back
+** (if the corresponding pDone bit is set) then skip the playback.
+** Make sure the pDone bit corresponding to the *pOffset page is set
+** prior to returning.
 **
-** Unused space within the cell content area is collected into a linked list of
-** freeblocks.  Each freeblock is at least 4 bytes in size.  The byte offset
-** to the first freeblock is given in the header.  Freeblocks occur in
-** increasing order.  Because a freeblock must be at least 4 bytes in size,
-** any group of 3 or fewer unused bytes in the cell content area cannot
-** exist on the freeblock chain.  A group of 3 or fewer free bytes is called
-** a fragment.  The total number of bytes in all fragments is recorded.
-** in the page header at offset 7.
+** If the page record is successfully read from the (sub-)journal file
+** and played back, then SQLITE_OK is returned. If an IO error occurs
+** while reading the record from the (sub-)journal file or while writing
+** to the database file, then the IO error code is returned. If data
+** is successfully read from the (sub-)journal file but appears to be
+** corrupted, SQLITE_DONE is returned. Data is considered corrupted in
+** two circumstances:
+** 
+**   * If the record page-number is illegal (0 or PAGER_MJ_PGNO), or
+**   * If the record is being rolled back from the main journal file
+**     and the checksum field does not match the record content.
 **
-**    SIZE    DESCRIPTION
-**      2     Byte offset of the next freeblock
-**      2     Bytes in this freeblock
+** Neither of these two scenarios are possible during a savepoint rollback.
 **
-** Cells are of variable length.  Cells are stored in the cell content area at
-** the end of the page.  Pointers to the cells are in the cell pointer array
-** that immediately follows the page header.  Cells is not necessarily
-** contiguous or in order, but cell pointers are contiguous and in order.
+** If this is a savepoint rollback, then memory may have to be dynamically
+** allocated by this function. If this is the case and an allocation fails,
+** SQLITE_NOMEM is returned.
+*/
+static int pager_playback_one_page(
+  Pager *pPager,                /* The pager being played back */
+  int isMainJrnl,               /* 1 -> main journal. 0 -> sub-journal. */
+  int isUnsync,                 /* True if reading from unsynced main journal */
+  i64 *pOffset,                 /* Offset of record to playback */
+  int isSavepnt,                /* True for a savepoint rollback */
+  Bitvec *pDone                 /* Bitvec of pages already played back */
+){
+  int rc;
+  PgHdr *pPg;                   /* An existing page in the cache */
+  Pgno pgno;                    /* The page number of a page in journal */
+  u32 cksum;                    /* Checksum used for sanity checking */
+  u8 *aData;                    /* Temporary storage for the page */
+  sqlite3_file *jfd;            /* The file descriptor for the journal file */
+
+  assert( (isMainJrnl&~1)==0 );      /* isMainJrnl is 0 or 1 */
+  assert( (isSavepnt&~1)==0 );       /* isSavepnt is 0 or 1 */
+  assert( isMainJrnl || pDone );     /* pDone always used on sub-journals */
+  assert( isSavepnt || pDone==0 );   /* pDone never used on non-savepoint */
+
+  aData = (u8*)pPager->pTmpSpace;
+  assert( aData );         /* Temp storage must have already been allocated */
+
+  /* Read the page number and page data from the journal or sub-journal
+  ** file. Return an error code to the caller if an IO error occurs.
+  */
+  jfd = isMainJrnl ? pPager->jfd : pPager->sjfd;
+  rc = read32bits(jfd, *pOffset, &pgno);
+  if( rc!=SQLITE_OK ) return rc;
+  rc = sqlite3OsRead(jfd, aData, pPager->pageSize, (*pOffset)+4);
+  if( rc!=SQLITE_OK ) return rc;
+  *pOffset += pPager->pageSize + 4 + isMainJrnl*4;
+
+  /* Sanity checking on the page.  This is more important that I originally
+  ** thought.  If a power failure occurs while the journal is being written,
+  ** it could cause invalid data to be written into the journal.  We need to
+  ** detect this invalid data (with high probability) and ignore it.
+  */
+  if( pgno==0 || pgno==PAGER_MJ_PGNO(pPager) ){
+    assert( !isSavepnt );
+    return SQLITE_DONE;
+  }
+  if( pgno>(Pgno)pPager->dbSize || sqlite3BitvecTest(pDone, pgno) ){
+    return SQLITE_OK;
+  }
+  if( isMainJrnl ){
+    rc = read32bits(jfd, (*pOffset)-4, &cksum);
+    if( rc ) return rc;
+    if( !isSavepnt && pager_cksum(pPager, aData)!=cksum ){
+      return SQLITE_DONE;
+    }
+  }
+
+  if( pDone && (rc = sqlite3BitvecSet(pDone, pgno))!=SQLITE_OK ){
+    return rc;
+  }
+
+  assert( pPager->state==PAGER_RESERVED || pPager->state>=PAGER_EXCLUSIVE );
+
+  /* If the pager is in RESERVED state, then there must be a copy of this
+  ** page in the pager cache. In this case just update the pager cache,
+  ** not the database file. The page is left marked dirty in this case.
+  **
+  ** An exception to the above rule: If the database is in no-sync mode
+  ** and a page is moved during an incremental vacuum then the page may
+  ** not be in the pager cache. Later: if a malloc() or IO error occurs
+  ** during a Movepage() call, then the page may not be in the cache
+  ** either. So the condition described in the above paragraph is not
+  ** assert()able.
+  **
+  ** If in EXCLUSIVE state, then we update the pager cache if it exists
+  ** and the main file. The page is then marked not dirty.
+  **
+  ** Ticket #1171:  The statement journal might contain page content that is
+  ** different from the page content at the start of the transaction.
+  ** This occurs when a page is changed prior to the start of a statement
+  ** then changed again within the statement.  When rolling back such a
+  ** statement we must not write to the original database unless we know
+  ** for certain that original page contents are synced into the main rollback
+  ** journal.  Otherwise, a power loss might leave modified data in the
+  ** database file without an entry in the rollback journal that can
+  ** restore the database to its original form.  Two conditions must be
+  ** met before writing to the database files. (1) the database must be
+  ** locked.  (2) we know that the original page content is fully synced
+  ** in the main journal either because the page is not in cache or else
+  ** the page is marked as needSync==0.
+  **
+  ** 2008-04-14:  When attempting to vacuum a corrupt database file, it
+  ** is possible to fail a statement on a database that does not yet exist.
+  ** Do not attempt to write if database file has never been opened.
+  */
+  pPg = pager_lookup(pPager, pgno);
+  assert( pPg || !MEMDB );
+  PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
+               PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, aData),
+               (isMainJrnl?"main-journal":"sub-journal")
+  ));
+  if( (pPager->state>=PAGER_EXCLUSIVE)
+   && (pPg==0 || 0==(pPg->flags&PGHDR_NEED_SYNC))
+   && isOpen(pPager->fd)
+   && !isUnsync
+  ){
+    i64 ofst = (pgno-1)*(i64)pPager->pageSize;
+    rc = sqlite3OsWrite(pPager->fd, aData, pPager->pageSize, ofst);
+    if( pgno>pPager->dbFileSize ){
+      pPager->dbFileSize = pgno;
+    }
+    if( pPager->pBackup ){
+      CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM);
+      sqlite3BackupUpdate(pPager->pBackup, pgno, aData);
+      CODEC1(pPager, aData, pgno, 0, rc=SQLITE_NOMEM);
+    }
+  }else if( !isMainJrnl && pPg==0 ){
+    /* If this is a rollback of a savepoint and data was not written to
+    ** the database and the page is not in-memory, there is a potential
+    ** problem. When the page is next fetched by the b-tree layer, it 
+    ** will be read from the database file, which may or may not be 
+    ** current. 
+    **
+    ** There are a couple of different ways this can happen. All are quite
+    ** obscure. When running in synchronous mode, this can only happen 
+    ** if the page is on the free-list at the start of the transaction, then
+    ** populated, then moved using sqlite3PagerMovepage().
+    **
+    ** The solution is to add an in-memory page to the cache containing
+    ** the data just read from the sub-journal. Mark the page as dirty 
+    ** and if the pager requires a journal-sync, then mark the page as 
+    ** requiring a journal-sync before it is written.
+    */
+    assert( isSavepnt );
+    if( (rc = sqlite3PagerAcquire(pPager, pgno, &pPg, 1))!=SQLITE_OK ){
+      return rc;
+    }
+    pPg->flags &= ~PGHDR_NEED_READ;
+    sqlite3PcacheMakeDirty(pPg);
+  }
+  if( pPg ){
+    /* No page should ever be explicitly rolled back that is in use, except
+    ** for page 1 which is held in use in order to keep the lock on the
+    ** database active. However such a page may be rolled back as a result
+    ** of an internal error resulting in an automatic call to
+    ** sqlite3PagerRollback().
+    */
+    void *pData;
+    pData = pPg->pData;
+    memcpy(pData, aData, pPager->pageSize);
+    pPager->xReiniter(pPg);
+    if( isMainJrnl && (!isSavepnt || *pOffset<=pPager->journalHdr) ){
+      /* If the contents of this page were just restored from the main 
+      ** journal file, then its content must be as they were when the 
+      ** transaction was first opened. In this case we can mark the page
+      ** as clean, since there will be no need to write it out to the.
+      **
+      ** There is one exception to this rule. If the page is being rolled
+      ** back as part of a savepoint (or statement) rollback from an 
+      ** unsynced portion of the main journal file, then it is not safe
+      ** to mark the page as clean. This is because marking the page as
+      ** clean will clear the PGHDR_NEED_SYNC flag. Since the page is
+      ** already in the journal file (recorded in Pager.pInJournal) and
+      ** the PGHDR_NEED_SYNC flag is cleared, if the page is written to
+      ** again within this transaction, it will be marked as dirty but
+      ** the PGHDR_NEED_SYNC flag will not be set. It could then potentially
+      ** be written out into the database file before its journal file
+      ** segment is synced. If a crash occurs during or following this,
+      ** database corruption may ensue.
+      */
+      sqlite3PcacheMakeClean(pPg);
+    }
+#ifdef SQLITE_CHECK_PAGES
+    pPg->pageHash = pager_pagehash(pPg);
+#endif
+    /* If this was page 1, then restore the value of Pager.dbFileVers.
+    ** Do this before any decoding. */
+    if( pgno==1 ){
+      memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));
+    }
+
+    /* Decode the page just read from disk */
+    CODEC1(pPager, pData, pPg->pgno, 3, rc=SQLITE_NOMEM);
+    sqlite3PcacheRelease(pPg);
+  }
+  return rc;
+}
+
+/*
+** Parameter zMaster is the name of a master journal file. A single journal
+** file that referred to the master journal file has just been rolled back.
+** This routine checks if it is possible to delete the master journal file,
+** and does so if it is.
 **
-** Cell content makes use of variable length integers.  A variable
-** length integer is 1 to 9 bytes where the lower 7 bits of each 
-** byte are used.  The integer consists of all bytes that have bit 8 set and
-** the first byte with bit 8 clear.  The most significant byte of the integer
-** appears first.  A variable-length integer may not be more than 9 bytes long.
-** As a special case, all 8 bytes of the 9th byte are used as data.  This
-** allows a 64-bit integer to be encoded in 9 bytes.
+** Argument zMaster may point to Pager.pTmpSpace. So that buffer is not 
+** available for use within this function.
 **
-**    0x00                      becomes  0x00000000
-**    0x7f                      becomes  0x0000007f
-**    0x81 0x00                 becomes  0x00000080
-**    0x82 0x00                 becomes  0x00000100
-**    0x80 0x7f                 becomes  0x0000007f
-**    0x8a 0x91 0xd1 0xac 0x78  becomes  0x12345678
-**    0x81 0x81 0x81 0x81 0x01  becomes  0x10204081
+** When a master journal file is created, it is populated with the names 
+** of all of its child journals, one after another, formatted as utf-8 
+** encoded text. The end of each child journal file is marked with a 
+** nul-terminator byte (0x00). i.e. the entire contents of a master journal
+** file for a transaction involving two databases might be:
 **
-** Variable length integers are used for rowids and to hold the number of
-** bytes of key and data in a btree cell.
+**   "/home/bill/a.db-journal\x00/home/bill/b.db-journal\x00"
 **
-** The content of a cell looks like this:
+** A master journal file may only be deleted once all of its child 
+** journals have been rolled back.
 **
-**    SIZE    DESCRIPTION
-**      4     Page number of the left child. Omitted if leaf flag is set.
-**     var    Number of bytes of data. Omitted if the zerodata flag is set.
-**     var    Number of bytes of key. Or the key itself if intkey flag is set.
-**      *     Payload
-**      4     First page of the overflow chain.  Omitted if no overflow
+** This function reads the contents of the master-journal file into 
+** memory and loops through each of the child journal names. For
+** each child journal, it checks if:
 **
-** Overflow pages form a linked list.  Each page except the last is completely
-** filled with data (pagesize - 4 bytes).  The last page can have as little
-** as 1 byte of data.
+**   * if the child journal exists, and if so
+**   * if the child journal contains a reference to master journal 
+**     file zMaster
 **
-**    SIZE    DESCRIPTION
-**      4     Page number of next overflow page
-**      *     Data
+** If a child journal can be found that matches both of the criteria
+** above, this function returns without doing anything. Otherwise, if
+** no such child journal can be found, file zMaster is deleted from
+** the file-system using sqlite3OsDelete().
 **
-** Freelist pages come in two subtypes: trunk pages and leaf pages.  The
-** file header points to the first in a linked list of trunk page.  Each trunk
-** page points to multiple leaf pages.  The content of a leaf page is
-** unspecified.  A trunk page looks like this:
+** If an IO error within this function, an error code is returned. This
+** function allocates memory by calling sqlite3Malloc(). If an allocation
+** fails, SQLITE_NOMEM is returned. Otherwise, if no IO or malloc errors 
+** occur, SQLITE_OK is returned.
 **
-**    SIZE    DESCRIPTION
-**      4     Page number of next trunk page
-**      4     Number of leaf pointers on this page
-**      *     zero or more pages numbers of leaves
+** TODO: This function allocates a single block of memory to load
+** the entire contents of the master journal file. This could be
+** a couple of kilobytes or so - potentially larger than the page 
+** size.
 */
+static int pager_delmaster(Pager *pPager, const char *zMaster){
+  sqlite3_vfs *pVfs = pPager->pVfs;
+  int rc;                   /* Return code */
+  sqlite3_file *pMaster;    /* Malloc'd master-journal file descriptor */
+  sqlite3_file *pJournal;   /* Malloc'd child-journal file descriptor */
+  char *zMasterJournal = 0; /* Contents of master journal file */
+  i64 nMasterJournal;       /* Size of master journal file */
 
-/* Round up a number to the next larger multiple of 8.  This is used
-** to force 8-byte alignment on 64-bit architectures.
-*/
-#define ROUND8(x)   ((x+7)&~7)
+  /* Allocate space for both the pJournal and pMaster file descriptors.
+  ** If successful, open the master journal file for reading.
+  */
+  pMaster = (sqlite3_file *)sqlite3MallocZero(pVfs->szOsFile * 2);
+  pJournal = (sqlite3_file *)(((u8 *)pMaster) + pVfs->szOsFile);
+  if( !pMaster ){
+    rc = SQLITE_NOMEM;
+  }else{
+    const int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MASTER_JOURNAL);
+    rc = sqlite3OsOpen(pVfs, zMaster, pMaster, flags, 0);
+  }
+  if( rc!=SQLITE_OK ) goto delmaster_out;
 
+  rc = sqlite3OsFileSize(pMaster, &nMasterJournal);
+  if( rc!=SQLITE_OK ) goto delmaster_out;
 
-/* The following value is the maximum cell size assuming a maximum page
-** size give above.
-*/
-#define MX_CELL_SIZE(pBt)  (pBt->pageSize-8)
+  if( nMasterJournal>0 ){
+    char *zJournal;
+    char *zMasterPtr = 0;
+    int nMasterPtr = pVfs->mxPathname+1;
 
-/* The maximum number of cells on a single page of the database.  This
-** assumes a minimum cell size of 6 bytes  (4 bytes for the cell itself
-** plus 2 bytes for the index to the cell in the page header).  Such
-** small cells will be rare, but they are possible.
-*/
-#define MX_CELL(pBt) ((pBt->pageSize-8)/6)
+    /* Load the entire master journal file into space obtained from
+    ** sqlite3_malloc() and pointed to by zMasterJournal. 
+    */
+    zMasterJournal = sqlite3Malloc((int)nMasterJournal + nMasterPtr + 1);
+    if( !zMasterJournal ){
+      rc = SQLITE_NOMEM;
+      goto delmaster_out;
+    }
+    zMasterPtr = &zMasterJournal[nMasterJournal+1];
+    rc = sqlite3OsRead(pMaster, zMasterJournal, (int)nMasterJournal, 0);
+    if( rc!=SQLITE_OK ) goto delmaster_out;
+    zMasterJournal[nMasterJournal] = 0;
 
-/* Forward declarations */
-typedef struct MemPage MemPage;
-typedef struct BtLock BtLock;
+    zJournal = zMasterJournal;
+    while( (zJournal-zMasterJournal)<nMasterJournal ){
+      int exists;
+      rc = sqlite3OsAccess(pVfs, zJournal, SQLITE_ACCESS_EXISTS, &exists);
+      if( rc!=SQLITE_OK ){
+        goto delmaster_out;
+      }
+      if( exists ){
+        /* One of the journals pointed to by the master journal exists.
+        ** Open it and check if it points at the master journal. If
+        ** so, return without deleting the master journal file.
+        */
+        int c;
+        int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL);
+        rc = sqlite3OsOpen(pVfs, zJournal, pJournal, flags, 0);
+        if( rc!=SQLITE_OK ){
+          goto delmaster_out;
+        }
 
-/*
-** This is a magic string that appears at the beginning of every
-** SQLite database in order to identify the file as a real database.
-**
-** You can change this value at compile-time by specifying a
-** -DSQLITE_FILE_HEADER="..." on the compiler command-line.  The
-** header must be exactly 16 bytes including the zero-terminator so
-** the string itself should be 15 characters long.  If you change
-** the header, then your custom library will not be able to read 
-** databases generated by the standard tools and the standard tools
-** will not be able to read databases created by your custom library.
-*/
-#ifndef SQLITE_FILE_HEADER /* 123456789 123456 */
-#  define SQLITE_FILE_HEADER "SQLite format 3"
-#endif
+        rc = readMasterJournal(pJournal, zMasterPtr, nMasterPtr);
+        sqlite3OsClose(pJournal);
+        if( rc!=SQLITE_OK ){
+          goto delmaster_out;
+        }
 
-/*
-** Page type flags.  An ORed combination of these flags appear as the
-** first byte of on-disk image of every BTree page.
-*/
-#define PTF_INTKEY    0x01
-#define PTF_ZERODATA  0x02
-#define PTF_LEAFDATA  0x04
-#define PTF_LEAF      0x08
+        c = zMasterPtr[0]!=0 && strcmp(zMasterPtr, zMaster)==0;
+        if( c ){
+          /* We have a match. Do not delete the master journal file. */
+          goto delmaster_out;
+        }
+      }
+      zJournal += (sqlite3Strlen30(zJournal)+1);
+    }
+  }
+  
+  rc = sqlite3OsDelete(pVfs, zMaster, 0);
 
-/*
-** As each page of the file is loaded into memory, an instance of the following
-** structure is appended and initialized to zero.  This structure stores
-** information about the page that is decoded from the raw file page.
-**
-** The pParent field points back to the parent page.  This allows us to
-** walk up the BTree from any leaf to the root.  Care must be taken to
-** unref() the parent page pointer when this page is no longer referenced.
-** The pageDestructor() routine handles that chore.
-**
-** Access to all fields of this structure is controlled by the mutex
-** stored in MemPage.pBt->mutex.
-*/
-struct MemPage {
-  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */
-  u8 idxShift;         /* True if Cell indices have changed */
-  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
-  u8 intKey;           /* True if intkey flag is set */
-  u8 leaf;             /* True if leaf flag is set */
-  u8 zeroData;         /* True if table stores keys only */
-  u8 leafData;         /* True if tables stores data on leaves only */
-  u8 hasData;          /* True if this page stores data */
-  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
-  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
-  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
-  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
-  u16 cellOffset;      /* Index in aData of first cell pointer */
-  u16 idxParent;       /* Index in parent of this node */
-  u16 nFree;           /* Number of free bytes on the page */
-  u16 nCell;           /* Number of cells on this page, local and ovfl */
-  struct _OvflCell {   /* Cells that will not fit on aData[] */
-    u8 *pCell;          /* Pointers to the body of the overflow cell */
-    u16 idx;            /* Insert this cell before idx-th non-overflow cell */
-  } aOvfl[5];
-  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
-  u8 *aData;           /* Pointer to disk image of the page data */
-  DbPage *pDbPage;     /* Pager page handle */
-  Pgno pgno;           /* Page number for this page */
-  MemPage *pParent;    /* The parent of this page.  NULL for root */
-};
+delmaster_out:
+  if( zMasterJournal ){
+    sqlite3_free(zMasterJournal);
+  }  
+  if( pMaster ){
+    sqlite3OsClose(pMaster);
+    assert( !isOpen(pJournal) );
+  }
+  sqlite3_free(pMaster);
+  return rc;
+}
 
-/*
-** The in-memory image of a disk page has the auxiliary information appended
-** to the end.  EXTRA_SIZE is the number of bytes of space needed to hold
-** that extra information.
-*/
-#define EXTRA_SIZE sizeof(MemPage)
 
-/* A Btree handle
+/*
+** This function is used to change the actual size of the database 
+** file in the file-system. This only happens when committing a transaction,
+** or rolling back a transaction (including rolling back a hot-journal).
 **
-** A database connection contains a pointer to an instance of
-** this object for every database file that it has open.  This structure
-** is opaque to the database connection.  The database connection cannot
-** see the internals of this structure and only deals with pointers to
-** this structure.
+** If the main database file is not open, or an exclusive lock is not
+** held, this function is a no-op. Otherwise, the size of the file is
+** changed to nPage pages (nPage*pPager->pageSize bytes). If the file
+** on disk is currently larger than nPage pages, then use the VFS
+** xTruncate() method to truncate it.
 **
-** For some database files, the same underlying database cache might be 
-** shared between multiple connections.  In that case, each contection
-** has it own pointer to this object.  But each instance of this object
-** points to the same BtShared object.  The database cache and the
-** schema associated with the database file are all contained within
-** the BtShared object.
+** Or, it might might be the case that the file on disk is smaller than 
+** nPage pages. Some operating system implementations can get confused if 
+** you try to truncate a file to some size that is larger than it 
+** currently is, so detect this case and write a single zero byte to 
+** the end of the new file instead.
 **
-** All fields in this structure are accessed under sqlite3.mutex.
-** The pBt pointer itself may not be changed while there exists cursors 
-** in the referenced BtShared that point back to this Btree since those
-** cursors have to do go through this Btree to find their BtShared and
-** they often do so without holding sqlite3.mutex.
+** If successful, return SQLITE_OK. If an IO error occurs while modifying
+** the database file, return the error code to the caller.
 */
-struct Btree {
-  sqlite3 *db;       /* The database connection holding this btree */
-  BtShared *pBt;     /* Sharable content of this btree */
-  u8 inTrans;        /* TRANS_NONE, TRANS_READ or TRANS_WRITE */
-  u8 sharable;       /* True if we can share pBt with another db */
-  u8 locked;         /* True if db currently has pBt locked */
-  int wantToLock;    /* Number of nested calls to sqlite3BtreeEnter() */
-  Btree *pNext;      /* List of other sharable Btrees from the same db */
-  Btree *pPrev;      /* Back pointer of the same list */
-};
+static int pager_truncate(Pager *pPager, Pgno nPage){
+  int rc = SQLITE_OK;
+  if( pPager->state>=PAGER_EXCLUSIVE && isOpen(pPager->fd) ){
+    i64 currentSize, newSize;
+    /* TODO: Is it safe to use Pager.dbFileSize here? */
+    rc = sqlite3OsFileSize(pPager->fd, &currentSize);
+    newSize = pPager->pageSize*(i64)nPage;
+    if( rc==SQLITE_OK && currentSize!=newSize ){
+      if( currentSize>newSize ){
+        rc = sqlite3OsTruncate(pPager->fd, newSize);
+      }else{
+        rc = sqlite3OsWrite(pPager->fd, "", 1, newSize-1);
+      }
+      if( rc==SQLITE_OK ){
+        pPager->dbFileSize = nPage;
+      }
+    }
+  }
+  return rc;
+}
 
 /*
-** Btree.inTrans may take one of the following values.
+** Set the value of the Pager.sectorSize variable for the given
+** pager based on the value returned by the xSectorSize method
+** of the open database file. The sector size will be used used 
+** to determine the size and alignment of journal header and 
+** master journal pointers within created journal files.
 **
-** If the shared-data extension is enabled, there may be multiple users
-** of the Btree structure. At most one of these may open a write transaction,
-** but any number may have active read transactions.
+** For temporary files the effective sector size is always 512 bytes.
+**
+** Otherwise, for non-temporary files, the effective sector size is
+** the value returned by the xSectorSize() method rounded up to 512 if
+** it is less than 512, or rounded down to MAX_SECTOR_SIZE if it
+** is greater than MAX_SECTOR_SIZE.
 */
-#define TRANS_NONE  0
-#define TRANS_READ  1
-#define TRANS_WRITE 2
+static void setSectorSize(Pager *pPager){
+  assert( isOpen(pPager->fd) || pPager->tempFile );
+
+  if( !pPager->tempFile ){
+    /* Sector size doesn't matter for temporary files. Also, the file
+    ** may not have been opened yet, in which case the OsSectorSize()
+    ** call will segfault.
+    */
+    pPager->sectorSize = sqlite3OsSectorSize(pPager->fd);
+  }
+  if( pPager->sectorSize<512 ){
+    pPager->sectorSize = 512;
+  }
+  if( pPager->sectorSize>MAX_SECTOR_SIZE ){
+    assert( MAX_SECTOR_SIZE>=512 );
+    pPager->sectorSize = MAX_SECTOR_SIZE;
+  }
+}
 
 /*
-** An instance of this object represents a single database file.
-** 
-** A single database file can be in use as the same time by two
-** or more database connections.  When two or more connections are
-** sharing the same database file, each connection has it own
-** private Btree object for the file and each of those Btrees points
-** to this one BtShared object.  BtShared.nRef is the number of
-** connections currently sharing this database file.
-**
-** Fields in this structure are accessed under the BtShared.mutex
-** mutex, except for nRef and pNext which are accessed under the
-** global SQLITE_MUTEX_STATIC_MASTER mutex.  The pPager field
-** may not be modified once it is initially set as long as nRef>0.
-** The pSchema field may be set once under BtShared.mutex and
-** thereafter is unchanged as long as nRef>0.
-*/
-struct BtShared {
-  Pager *pPager;        /* The page cache */
-  sqlite3 *db;          /* Database connection currently using this Btree */
-  BtCursor *pCursor;    /* A list of all open cursors */
-  MemPage *pPage1;      /* First page of the database */
-  u8 inStmt;            /* True if we are in a statement subtransaction */
-  u8 readOnly;          /* True if the underlying file is readonly */
-  u8 maxEmbedFrac;      /* Maximum payload as % of total page size */
-  u8 minEmbedFrac;      /* Minimum payload as % of total page size */
-  u8 minLeafFrac;       /* Minimum leaf payload as % of total page size */
-  u8 pageSizeFixed;     /* True if the page size can no longer be changed */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  u8 autoVacuum;        /* True if auto-vacuum is enabled */
-  u8 incrVacuum;        /* True if incr-vacuum is enabled */
-  Pgno nTrunc;          /* Non-zero if the db will be truncated (incr vacuum) */
-#endif
-  u16 pageSize;         /* Total number of bytes on a page */
-  u16 usableSize;       /* Number of usable bytes on each page */
-  int maxLocal;         /* Maximum local payload in non-LEAFDATA tables */
-  int minLocal;         /* Minimum local payload in non-LEAFDATA tables */
-  int maxLeaf;          /* Maximum local payload in a LEAFDATA table */
-  int minLeaf;          /* Minimum local payload in a LEAFDATA table */
-  u8 inTransaction;     /* Transaction state */
-  int nTransaction;     /* Number of open transactions (read + write) */
-  void *pSchema;        /* Pointer to space allocated by sqlite3BtreeSchema() */
-  void (*xFreeSchema)(void*);  /* Destructor for BtShared.pSchema */
-  sqlite3_mutex *mutex; /* Non-recursive mutex required to access this struct */
-  BusyHandler busyHdr;  /* The busy handler for this btree */
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  int nRef;             /* Number of references to this structure */
-  BtShared *pNext;      /* Next on a list of sharable BtShared structs */
-  BtLock *pLock;        /* List of locks held on this shared-btree struct */
-  Btree *pExclusive;    /* Btree with an EXCLUSIVE lock on the whole db */
-#endif
-  u8 *pTmpSpace;        /* BtShared.pageSize bytes of space for tmp use */
-};
-
-/*
-** An instance of the following structure is used to hold information
-** about a cell.  The parseCellPtr() function fills in this structure
-** based on information extract from the raw disk page.
-*/
-typedef struct CellInfo CellInfo;
-struct CellInfo {
-  u8 *pCell;     /* Pointer to the start of cell content */
-  i64 nKey;      /* The key for INTKEY tables, or number of bytes in key */
-  u32 nData;     /* Number of bytes of data */
-  u32 nPayload;  /* Total amount of payload */
-  u16 nHeader;   /* Size of the cell content header in bytes */
-  u16 nLocal;    /* Amount of payload held locally */
-  u16 iOverflow; /* Offset to overflow page number.  Zero if no overflow */
-  u16 nSize;     /* Size of the cell content on the main b-tree page */
-};
-
-/*
-** A cursor is a pointer to a particular entry within a particular
-** b-tree within a database file.
+** Playback the journal and thus restore the database file to
+** the state it was in before we started making changes.  
 **
-** The entry is identified by its MemPage and the index in
-** MemPage.aCell[] of the entry.
+** The journal file format is as follows: 
 **
-** When a single database file can shared by two more database connections,
-** but cursors cannot be shared.  Each cursor is associated with a
-** particular database connection identified BtCursor.pBtree.db.
+**  (1)  8 byte prefix.  A copy of aJournalMagic[].
+**  (2)  4 byte big-endian integer which is the number of valid page records
+**       in the journal.  If this value is 0xffffffff, then compute the
+**       number of page records from the journal size.
+**  (3)  4 byte big-endian integer which is the initial value for the 
+**       sanity checksum.
+**  (4)  4 byte integer which is the number of pages to truncate the
+**       database to during a rollback.
+**  (5)  4 byte big-endian integer which is the sector size.  The header
+**       is this many bytes in size.
+**  (6)  4 byte big-endian integer which is the page case.
+**  (7)  4 byte integer which is the number of bytes in the master journal
+**       name.  The value may be zero (indicate that there is no master
+**       journal.)
+**  (8)  N bytes of the master journal name.  The name will be nul-terminated
+**       and might be shorter than the value read from (5).  If the first byte
+**       of the name is \000 then there is no master journal.  The master
+**       journal name is stored in UTF-8.
+**  (9)  Zero or more pages instances, each as follows:
+**        +  4 byte page number.
+**        +  pPager->pageSize bytes of data.
+**        +  4 byte checksum
 **
-** Fields in this structure are accessed under the BtShared.mutex
-** found at self->pBt->mutex. 
-*/
-struct BtCursor {
-  Btree *pBtree;            /* The Btree to which this cursor belongs */
-  BtShared *pBt;            /* The BtShared this cursor points to */
-  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
-  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
-  Pgno pgnoRoot;            /* The root page of this tree */
-  MemPage *pPage;           /* Page that contains the entry */
-  int idx;                  /* Index of the entry in pPage->aCell[] */
-  CellInfo info;            /* A parse of the cell we are pointing at */
-  u8 wrFlag;                /* True if writable */
-  u8 atLast;                /* Cursor pointing to the last entry */
-  u8 validNKey;             /* True if info.nKey is valid */
-  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
-  void *pKey;      /* Saved key that was cursor's last known position */
-  i64 nKey;        /* Size of pKey, or last integer key */
-  int skip;        /* (skip<0) -> Prev() is a no-op. (skip>0) -> Next() is */
-#ifndef SQLITE_OMIT_INCRBLOB
-  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
-  Pgno *aOverflow;          /* Cache of overflow page locations */
-#endif
-};
-
-/*
-** Potential values for BtCursor.eState.
+** When we speak of the journal header, we mean the first 8 items above.
+** Each entry in the journal is an instance of the 9th item.
 **
-** CURSOR_VALID:
-**   Cursor points to a valid entry. getPayload() etc. may be called.
+** Call the value from the second bullet "nRec".  nRec is the number of
+** valid page entries in the journal.  In most cases, you can compute the
+** value of nRec from the size of the journal file.  But if a power
+** failure occurred while the journal was being written, it could be the
+** case that the size of the journal file had already been increased but
+** the extra entries had not yet made it safely to disk.  In such a case,
+** the value of nRec computed from the file size would be too large.  For
+** that reason, we always use the nRec value in the header.
 **
-** CURSOR_INVALID:
-**   Cursor does not point to a valid entry. This can happen (for example) 
-**   because the table is empty or because BtreeCursorFirst() has not been
-**   called.
+** If the nRec value is 0xffffffff it means that nRec should be computed
+** from the file size.  This value is used when the user selects the
+** no-sync option for the journal.  A power failure could lead to corruption
+** in this case.  But for things like temporary table (which will be
+** deleted when the power is restored) we don't care.  
 **
-** CURSOR_REQUIRESEEK:
-**   The table that this cursor was opened on still exists, but has been 
-**   modified since the cursor was last used. The cursor position is saved
-**   in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in 
-**   this state, restoreOrClearCursorPosition() can be called to attempt to
-**   seek the cursor to the saved position.
+** If the file opened as the journal file is not a well-formed
+** journal file then all pages up to the first corrupted page are rolled
+** back (or no pages if the journal header is corrupted). The journal file
+** is then deleted and SQLITE_OK returned, just as if no corruption had
+** been encountered.
 **
-** CURSOR_FAULT:
-**   A unrecoverable error (an I/O error or a malloc failure) has occurred
-**   on a different connection that shares the BtShared cache with this
-**   cursor.  The error has left the cache in an inconsistent state.
-**   Do nothing else with this cursor.  Any attempt to use the cursor
-**   should return the error code stored in BtCursor.skip
-*/
-#define CURSOR_INVALID           0
-#define CURSOR_VALID             1
-#define CURSOR_REQUIRESEEK       2
-#define CURSOR_FAULT             3
-
-/*
-** The TRACE macro will print high-level status information about the
-** btree operation when the global variable sqlite3BtreeTrace is
-** enabled.
-*/
-#if SQLITE_TEST
-# define TRACE(X)   if( sqlite3BtreeTrace ){ printf X; fflush(stdout); }
-#else
-# define TRACE(X)
-#endif
-
-/* The database page the PENDING_BYTE occupies. This page is never used.
-** TODO: This macro is very similary to PAGER_MJ_PGNO() in pager.c. They
-** should possibly be consolidated (presumably in pager.h).
+** If an I/O or malloc() error occurs, the journal-file is not deleted
+** and an error code is returned.
 **
-** If disk I/O is omitted (meaning that the database is stored purely
-** in memory) then there is no pending byte.
-*/
-#ifdef SQLITE_OMIT_DISKIO
-# define PENDING_BYTE_PAGE(pBt)  0x7fffffff
-#else
-# define PENDING_BYTE_PAGE(pBt) ((PENDING_BYTE/(pBt)->pageSize)+1)
-#endif
-
-/*
-** A linked list of the following structures is stored at BtShared.pLock.
-** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor 
-** is opened on the table with root page BtShared.iTable. Locks are removed
-** from this list when a transaction is committed or rolled back, or when
-** a btree handle is closed.
+** The isHot parameter indicates that we are trying to rollback a journal
+** that might be a hot journal.  Or, it could be that the journal is 
+** preserved because of JOURNALMODE_PERSIST or JOURNALMODE_TRUNCATE.
+** If the journal really is hot, reset the pager cache prior rolling
+** back any content.  If the journal is merely persistent, no reset is
+** needed.
 */
-struct BtLock {
-  Btree *pBtree;        /* Btree handle holding this lock */
-  Pgno iTable;          /* Root page of table */
-  u8 eLock;             /* READ_LOCK or WRITE_LOCK */
-  BtLock *pNext;        /* Next in BtShared.pLock list */
-};
+static int pager_playback(Pager *pPager, int isHot){
+  sqlite3_vfs *pVfs = pPager->pVfs;
+  i64 szJ;                 /* Size of the journal file in bytes */
+  u32 nRec;                /* Number of Records in the journal */
+  u32 u;                   /* Unsigned loop counter */
+  Pgno mxPg = 0;           /* Size of the original file in pages */
+  int rc;                  /* Result code of a subroutine */
+  int res = 1;             /* Value returned by sqlite3OsAccess() */
+  char *zMaster = 0;       /* Name of master journal file if any */
+  int needPagerReset;      /* True to reset page prior to first page rollback */
 
-/* Candidate values for BtLock.eLock */
-#define READ_LOCK     1
-#define WRITE_LOCK    2
+  /* Figure out how many records are in the journal.  Abort early if
+  ** the journal is empty.
+  */
+  assert( isOpen(pPager->jfd) );
+  rc = sqlite3OsFileSize(pPager->jfd, &szJ);
+  if( rc!=SQLITE_OK || szJ==0 ){
+    goto end_playback;
+  }
 
-/*
-** These macros define the location of the pointer-map entry for a 
-** database page. The first argument to each is the number of usable
-** bytes on each page of the database (often 1024). The second is the
-** page number to look up in the pointer map.
-**
-** PTRMAP_PAGENO returns the database page number of the pointer-map
-** page that stores the required pointer. PTRMAP_PTROFFSET returns
-** the offset of the requested map entry.
-**
-** If the pgno argument passed to PTRMAP_PAGENO is a pointer-map page,
-** then pgno is returned. So (pgno==PTRMAP_PAGENO(pgsz, pgno)) can be
-** used to test if pgno is a pointer-map page. PTRMAP_ISPAGE implements
-** this test.
-*/
-#define PTRMAP_PAGENO(pBt, pgno) ptrmapPageno(pBt, pgno)
-#define PTRMAP_PTROFFSET(pBt, pgno) (5*(pgno-ptrmapPageno(pBt, pgno)-1))
-#define PTRMAP_ISPAGE(pBt, pgno) (PTRMAP_PAGENO((pBt),(pgno))==(pgno))
+  /* Read the master journal name from the journal, if it is present.
+  ** If a master journal file name is specified, but the file is not
+  ** present on disk, then the journal is not hot and does not need to be
+  ** played back.
+  **
+  ** TODO: Technically the following is an error because it assumes that
+  ** buffer Pager.pTmpSpace is (mxPathname+1) bytes or larger. i.e. that
+  ** (pPager->pageSize >= pPager->pVfs->mxPathname+1). Using os_unix.c,
+  **  mxPathname is 512, which is the same as the minimum allowable value
+  ** for pageSize.
+  */
+  zMaster = pPager->pTmpSpace;
+  rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+  if( rc==SQLITE_OK && zMaster[0] ){
+    rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
+  }
+  zMaster = 0;
+  if( rc!=SQLITE_OK || !res ){
+    goto end_playback;
+  }
+  pPager->journalOff = 0;
+  needPagerReset = isHot;
 
-/*
-** The pointer map is a lookup table that identifies the parent page for
-** each child page in the database file.  The parent page is the page that
-** contains a pointer to the child.  Every page in the database contains
-** 0 or 1 parent pages.  (In this context 'database page' refers
-** to any page that is not part of the pointer map itself.)  Each pointer map
-** entry consists of a single byte 'type' and a 4 byte parent page number.
-** The PTRMAP_XXX identifiers below are the valid types.
-**
-** The purpose of the pointer map is to facility moving pages from one
-** position in the file to another as part of autovacuum.  When a page
-** is moved, the pointer in its parent must be updated to point to the
-** new location.  The pointer map is used to locate the parent page quickly.
-**
-** PTRMAP_ROOTPAGE: The database page is a root-page. The page-number is not
-**                  used in this case.
-**
-** PTRMAP_FREEPAGE: The database page is an unused (free) page. The page-number 
-**                  is not used in this case.
-**
-** PTRMAP_OVERFLOW1: The database page is the first page in a list of 
-**                   overflow pages. The page number identifies the page that
-**                   contains the cell with a pointer to this overflow page.
-**
-** PTRMAP_OVERFLOW2: The database page is the second or later page in a list of
-**                   overflow pages. The page-number identifies the previous
-**                   page in the overflow page list.
-**
-** PTRMAP_BTREE: The database page is a non-root btree page. The page number
-**               identifies the parent page in the btree.
-*/
-#define PTRMAP_ROOTPAGE 1
-#define PTRMAP_FREEPAGE 2
-#define PTRMAP_OVERFLOW1 3
-#define PTRMAP_OVERFLOW2 4
-#define PTRMAP_BTREE 5
+  /* This loop terminates either when a readJournalHdr() or 
+  ** pager_playback_one_page() call returns SQLITE_DONE or an IO error 
+  ** occurs. 
+  */
+  while( 1 ){
+    int isUnsync = 0;
 
-/* A bunch of assert() statements to check the transaction state variables
-** of handle p (type Btree*) are internally consistent.
-*/
-#define btreeIntegrity(p) \
-  assert( p->pBt->inTransaction!=TRANS_NONE || p->pBt->nTransaction==0 ); \
-  assert( p->pBt->inTransaction>=p->inTrans ); 
+    /* Read the next journal header from the journal file.  If there are
+    ** not enough bytes left in the journal file for a complete header, or
+    ** it is corrupted, then a process must of failed while writing it.
+    ** This indicates nothing more needs to be rolled back.
+    */
+    rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
+    if( rc!=SQLITE_OK ){ 
+      if( rc==SQLITE_DONE ){
+        rc = SQLITE_OK;
+      }
+      goto end_playback;
+    }
 
+    /* If nRec is 0xffffffff, then this journal was created by a process
+    ** working in no-sync mode. This means that the rest of the journal
+    ** file consists of pages, there are no more journal headers. Compute
+    ** the value of nRec based on this assumption.
+    */
+    if( nRec==0xffffffff ){
+      assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) );
+      nRec = (int)((szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager));
+    }
 
-/*
-** The ISAUTOVACUUM macro is used within balance_nonroot() to determine
-** if the database supports auto-vacuum or not. Because it is used
-** within an expression that is an argument to another macro 
-** (sqliteMallocRaw), it is not possible to use conditional compilation.
-** So, this macro is defined instead.
-*/
-#ifndef SQLITE_OMIT_AUTOVACUUM
-#define ISAUTOVACUUM (pBt->autoVacuum)
-#else
-#define ISAUTOVACUUM 0
-#endif
+    /* If nRec is 0 and this rollback is of a transaction created by this
+    ** process and if this is the final header in the journal, then it means
+    ** that this part of the journal was being filled but has not yet been
+    ** synced to disk.  Compute the number of pages based on the remaining
+    ** size of the file.
+    **
+    ** The third term of the test was added to fix ticket #2565.
+    ** When rolling back a hot journal, nRec==0 always means that the next
+    ** chunk of the journal contains zero pages to be rolled back.  But
+    ** when doing a ROLLBACK and the nRec==0 chunk is the last chunk in
+    ** the journal, it means that the journal might contain additional
+    ** pages that need to be rolled back and that the number of pages 
+    ** should be computed based on the journal file size.
+    */
+    if( nRec==0 && !isHot &&
+        pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff ){
+      nRec = (int)((szJ - pPager->journalOff) / JOURNAL_PG_SZ(pPager));
+      isUnsync = 1;
+    }
 
+    /* If this is the first header read from the journal, truncate the
+    ** database file back to its original size.
+    */
+    if( pPager->journalOff==JOURNAL_HDR_SZ(pPager) ){
+      rc = pager_truncate(pPager, mxPg);
+      if( rc!=SQLITE_OK ){
+        goto end_playback;
+      }
+      pPager->dbSize = mxPg;
+    }
 
-/*
-** This structure is passed around through all the sanity checking routines
-** in order to keep track of some global state information.
-*/
-typedef struct IntegrityCk IntegrityCk;
-struct IntegrityCk {
-  BtShared *pBt;    /* The tree being checked out */
-  Pager *pPager;    /* The associated pager.  Also accessible by pBt->pPager */
-  int nPage;        /* Number of pages in the database */
-  int *anRef;       /* Number of times each page is referenced */
-  int mxErr;        /* Stop accumulating errors when this reaches zero */
-  char *zErrMsg;    /* An error message.  NULL if no errors seen. */
-  int nErr;         /* Number of messages written to zErrMsg so far */
-};
+    /* Copy original pages out of the journal and back into the 
+    ** database file and/or page cache.
+    */
+    for(u=0; u<nRec; u++){
+      if( needPagerReset ){
+        pager_reset(pPager);
+        needPagerReset = 0;
+      }
+      rc = pager_playback_one_page(pPager,1,isUnsync,&pPager->journalOff,0,0);
+      if( rc!=SQLITE_OK ){
+        if( rc==SQLITE_DONE ){
+          rc = SQLITE_OK;
+          pPager->journalOff = szJ;
+          break;
+        }else{
+          /* If we are unable to rollback, quit and return the error
+          ** code.  This will cause the pager to enter the error state
+          ** so that no further harm will be done.  Perhaps the next
+          ** process to come along will be able to rollback the database.
+          */
+          goto end_playback;
+        }
+      }
+    }
+  }
+  /*NOTREACHED*/
+  assert( 0 );
 
-/*
-** Read or write a two- and four-byte big-endian integer values.
-*/
-#define get2byte(x)   ((x)[0]<<8 | (x)[1])
-#define put2byte(p,v) ((p)[0] = (v)>>8, (p)[1] = (v))
-#define get4byte sqlite3Get4byte
-#define put4byte sqlite3Put4byte
+end_playback:
+  /* Following a rollback, the database file should be back in its original
+  ** state prior to the start of the transaction, so invoke the
+  ** SQLITE_FCNTL_DB_UNCHANGED file-control method to disable the
+  ** assertion that the transaction counter was modified.
+  */
+  assert(
+    pPager->fd->pMethods==0 ||
+    sqlite3OsFileControl(pPager->fd,SQLITE_FCNTL_DB_UNCHANGED,0)>=SQLITE_OK
+  );
 
-/*
-** Internal routines that should be accessed by the btree layer only.
-*/
-SQLITE_PRIVATE int sqlite3BtreeGetPage(BtShared*, Pgno, MemPage**, int);
-SQLITE_PRIVATE int sqlite3BtreeInitPage(MemPage *pPage, MemPage *pParent);
-SQLITE_PRIVATE void sqlite3BtreeParseCellPtr(MemPage*, u8*, CellInfo*);
-SQLITE_PRIVATE void sqlite3BtreeParseCell(MemPage*, int, CellInfo*);
-#ifdef SQLITE_TEST
-SQLITE_PRIVATE u8 *sqlite3BtreeFindCell(MemPage *pPage, int iCell);
-#endif
-SQLITE_PRIVATE int sqlite3BtreeRestoreOrClearCursorPosition(BtCursor *pCur);
-SQLITE_PRIVATE void sqlite3BtreeGetTempCursor(BtCursor *pCur, BtCursor *pTempCur);
-SQLITE_PRIVATE void sqlite3BtreeReleaseTempCursor(BtCursor *pCur);
-SQLITE_PRIVATE int sqlite3BtreeIsRootPage(MemPage *pPage);
-SQLITE_PRIVATE void sqlite3BtreeMoveToParent(BtCursor *pCur);
+  /* If this playback is happening automatically as a result of an IO or 
+  ** malloc error that occurred after the change-counter was updated but 
+  ** before the transaction was committed, then the change-counter 
+  ** modification may just have been reverted. If this happens in exclusive 
+  ** mode, then subsequent transactions performed by the connection will not
+  ** update the change-counter at all. This may lead to cache inconsistency
+  ** problems for other processes at some point in the future. So, just
+  ** in case this has happened, clear the changeCountDone flag now.
+  */
+  pPager->changeCountDone = pPager->tempFile;
 
-/************** End of btreeInt.h ********************************************/
-/************** Continuing where we left off in btmutex.c ********************/
-#if SQLITE_THREADSAFE && !defined(SQLITE_OMIT_SHARED_CACHE)
+  if( rc==SQLITE_OK ){
+    zMaster = pPager->pTmpSpace;
+    rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+    testcase( rc!=SQLITE_OK );
+  }
+  if( rc==SQLITE_OK ){
+    rc = pager_end_transaction(pPager, zMaster[0]!='\0');
+    testcase( rc!=SQLITE_OK );
+  }
+  if( rc==SQLITE_OK && zMaster[0] && res ){
+    /* If there was a master journal and this routine will return success,
+    ** see if it is possible to delete the master journal.
+    */
+    rc = pager_delmaster(pPager, zMaster);
+    testcase( rc!=SQLITE_OK );
+  }
 
+  /* The Pager.sectorSize variable may have been updated while rolling
+  ** back a journal created by a process with a different sector size
+  ** value. Reset it to the correct value for this process.
+  */
+  setSectorSize(pPager);
+  return rc;
+}
 
 /*
-** Enter a mutex on the given BTree object.
+** Playback savepoint pSavepoint. Or, if pSavepoint==NULL, then playback
+** the entire master journal file. The case pSavepoint==NULL occurs when 
+** a ROLLBACK TO command is invoked on a SAVEPOINT that is a transaction 
+** savepoint.
 **
-** If the object is not sharable, then no mutex is ever required
-** and this routine is a no-op.  The underlying mutex is non-recursive.
-** But we keep a reference count in Btree.wantToLock so the behavior
-** of this interface is recursive.
+** When pSavepoint is not NULL (meaning a non-transaction savepoint is 
+** being rolled back), then the rollback consists of up to three stages,
+** performed in the order specified:
 **
-** To avoid deadlocks, multiple Btrees are locked in the same order
-** by all database connections.  The p->pNext is a list of other
-** Btrees belonging to the same database connection as the p Btree
-** which need to be locked after p.  If we cannot get a lock on
-** p, then first unlock all of the others on p->pNext, then wait
-** for the lock to become available on p, then relock all of the
-** subsequent Btrees that desire a lock.
+**   * Pages are played back from the main journal starting at byte
+**     offset PagerSavepoint.iOffset and continuing to 
+**     PagerSavepoint.iHdrOffset, or to the end of the main journal
+**     file if PagerSavepoint.iHdrOffset is zero.
+**
+**   * If PagerSavepoint.iHdrOffset is not zero, then pages are played
+**     back starting from the journal header immediately following 
+**     PagerSavepoint.iHdrOffset to the end of the main journal file.
+**
+**   * Pages are then played back from the sub-journal file, starting
+**     with the PagerSavepoint.iSubRec and continuing to the end of
+**     the journal file.
+**
+** Throughout the rollback process, each time a page is rolled back, the
+** corresponding bit is set in a bitvec structure (variable pDone in the
+** implementation below). This is used to ensure that a page is only
+** rolled back the first time it is encountered in either journal.
+**
+** If pSavepoint is NULL, then pages are only played back from the main
+** journal file. There is no need for a bitvec in this case.
+**
+** In either case, before playback commences the Pager.dbSize variable
+** is reset to the value that it held at the start of the savepoint 
+** (or transaction). No page with a page-number greater than this value
+** is played back. If one is encountered it is simply skipped.
 */
-SQLITE_PRIVATE void sqlite3BtreeEnter(Btree *p){
-  Btree *pLater;
+static int pagerPlaybackSavepoint(Pager *pPager, PagerSavepoint *pSavepoint){
+  i64 szJ;                 /* Effective size of the main journal */
+  i64 iHdrOff;             /* End of first segment of main-journal records */
+  int rc = SQLITE_OK;      /* Return code */
+  Bitvec *pDone = 0;       /* Bitvec to ensure pages played back only once */
 
-  /* Some basic sanity checking on the Btree.  The list of Btrees
-  ** connected by pNext and pPrev should be in sorted order by
-  ** Btree.pBt value. All elements of the list should belong to
-  ** the same connection. Only shared Btrees are on the list. */
-  assert( p->pNext==0 || p->pNext->pBt>p->pBt );
-  assert( p->pPrev==0 || p->pPrev->pBt<p->pBt );
-  assert( p->pNext==0 || p->pNext->db==p->db );
-  assert( p->pPrev==0 || p->pPrev->db==p->db );
-  assert( p->sharable || (p->pNext==0 && p->pPrev==0) );
+  assert( pPager->state>=PAGER_SHARED );
 
-  /* Check for locking consistency */
-  assert( !p->locked || p->wantToLock>0 );
-  assert( p->sharable || p->wantToLock==0 );
+  /* Allocate a bitvec to use to store the set of pages rolled back */
+  if( pSavepoint ){
+    pDone = sqlite3BitvecCreate(pSavepoint->nOrig);
+    if( !pDone ){
+      return SQLITE_NOMEM;
+    }
+  }
 
-  /* We should already hold a lock on the database connection */
-  assert( sqlite3_mutex_held(p->db->mutex) );
+  /* Set the database size back to the value it was before the savepoint 
+  ** being reverted was opened.
+  */
+  pPager->dbSize = pSavepoint ? pSavepoint->nOrig : pPager->dbOrigSize;
 
-  if( !p->sharable ) return;
-  p->wantToLock++;
-  if( p->locked ) return;
+  /* Use pPager->journalOff as the effective size of the main rollback
+  ** journal.  The actual file might be larger than this in
+  ** PAGER_JOURNALMODE_TRUNCATE or PAGER_JOURNALMODE_PERSIST.  But anything
+  ** past pPager->journalOff is off-limits to us.
+  */
+  szJ = pPager->journalOff;
 
-#ifndef SQLITE_MUTEX_NOOP
-  /* In most cases, we should be able to acquire the lock we
-  ** want without having to go throught the ascending lock
-  ** procedure that follows.  Just be sure not to block.
+  /* Begin by rolling back records from the main journal starting at
+  ** PagerSavepoint.iOffset and continuing to the next journal header.
+  ** There might be records in the main journal that have a page number
+  ** greater than the current database size (pPager->dbSize) but those
+  ** will be skipped automatically.  Pages are added to pDone as they
+  ** are played back.
   */
-  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
-    p->locked = 1;
-    return;
+  if( pSavepoint ){
+    iHdrOff = pSavepoint->iHdrOffset ? pSavepoint->iHdrOffset : szJ;
+    pPager->journalOff = pSavepoint->iOffset;
+    while( rc==SQLITE_OK && pPager->journalOff<iHdrOff ){
+      rc = pager_playback_one_page(pPager, 1, 0, &pPager->journalOff, 1, pDone);
+    }
+    assert( rc!=SQLITE_DONE );
+  }else{
+    pPager->journalOff = 0;
   }
 
-  /* To avoid deadlock, first release all locks with a larger
-  ** BtShared address.  Then acquire our lock.  Then reacquire
-  ** the other BtShared locks that we used to hold in ascending
-  ** order.
+  /* Continue rolling back records out of the main journal starting at
+  ** the first journal header seen and continuing until the effective end
+  ** of the main journal file.  Continue to skip out-of-range pages and
+  ** continue adding pages rolled back to pDone.
   */
-  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
-    assert( pLater->sharable );
-    assert( pLater->pNext==0 || pLater->pNext->pBt>pLater->pBt );
-    assert( !pLater->locked || pLater->wantToLock>0 );
-    if( pLater->locked ){
-      sqlite3_mutex_leave(pLater->pBt->mutex);
-      pLater->locked = 0;
+  while( rc==SQLITE_OK && pPager->journalOff<szJ ){
+    u32 ii;            /* Loop counter */
+    u32 nJRec = 0;     /* Number of Journal Records */
+    u32 dummy;
+    rc = readJournalHdr(pPager, 0, szJ, &nJRec, &dummy);
+    assert( rc!=SQLITE_DONE );
+
+    /*
+    ** The "pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff"
+    ** test is related to ticket #2565.  See the discussion in the
+    ** pager_playback() function for additional information.
+    */
+    if( nJRec==0 
+     && pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff
+    ){
+      nJRec = (u32)((szJ - pPager->journalOff)/JOURNAL_PG_SZ(pPager));
+    }
+    for(ii=0; rc==SQLITE_OK && ii<nJRec && pPager->journalOff<szJ; ii++){
+      rc = pager_playback_one_page(pPager, 1, 0, &pPager->journalOff, 1, pDone);
     }
+    assert( rc!=SQLITE_DONE );
   }
-  sqlite3_mutex_enter(p->pBt->mutex);
-  p->locked = 1;
-  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
-    if( pLater->wantToLock ){
-      sqlite3_mutex_enter(pLater->pBt->mutex);
-      pLater->locked = 1;
+  assert( rc!=SQLITE_OK || pPager->journalOff==szJ );
+
+  /* Finally,  rollback pages from the sub-journal.  Page that were
+  ** previously rolled back out of the main journal (and are hence in pDone)
+  ** will be skipped.  Out-of-range pages are also skipped.
+  */
+  if( pSavepoint ){
+    u32 ii;            /* Loop counter */
+    i64 offset = pSavepoint->iSubRec*(4+pPager->pageSize);
+    for(ii=pSavepoint->iSubRec; rc==SQLITE_OK && ii<pPager->nSubRec; ii++){
+      assert( offset==ii*(4+pPager->pageSize) );
+      rc = pager_playback_one_page(pPager, 0, 0, &offset, 1, pDone);
     }
+    assert( rc!=SQLITE_DONE );
+  }
+
+  sqlite3BitvecDestroy(pDone);
+  if( rc==SQLITE_OK ){
+    pPager->journalOff = szJ;
   }
-#endif /* SQLITE_MUTEX_NOOP */
+  return rc;
 }
 
 /*
-** Exit the recursive mutex on a Btree.
+** Change the maximum number of in-memory pages that are allowed.
 */
-SQLITE_PRIVATE void sqlite3BtreeLeave(Btree *p){
-  if( p->sharable ){
-    assert( p->wantToLock>0 );
-    p->wantToLock--;
-    if( p->wantToLock==0 ){
-      assert( p->locked );
-      sqlite3_mutex_leave(p->pBt->mutex);
-      p->locked = 0;
-    }
-  }
+SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
+  sqlite3PcacheSetCachesize(pPager->pPCache, mxPage);
 }
 
-#ifndef NDEBUG
 /*
-** Return true if the BtShared mutex is held on the btree.  
+** Adjust the robustness of the database to damage due to OS crashes
+** or power failures by changing the number of syncs()s when writing
+** the rollback journal.  There are three levels:
 **
-** This routine makes no determination one why or another if the
-** database connection mutex is held.
+**    OFF       sqlite3OsSync() is never called.  This is the default
+**              for temporary and transient files.
 **
-** This routine is used only from within assert() statements.
+**    NORMAL    The journal is synced once before writes begin on the
+**              database.  This is normally adequate protection, but
+**              it is theoretically possible, though very unlikely,
+**              that an inopertune power failure could leave the journal
+**              in a state which would cause damage to the database
+**              when it is rolled back.
+**
+**    FULL      The journal is synced twice before writes begin on the
+**              database (with some additional information - the nRec field
+**              of the journal header - being written in between the two
+**              syncs).  If we assume that writing a
+**              single disk sector is atomic, then this mode provides
+**              assurance that the journal will not be corrupted to the
+**              point of causing damage to the database during rollback.
+**
+** Numeric values associated with these states are OFF==1, NORMAL=2,
+** and FULL=3.
 */
-SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree *p){
-  return (p->sharable==0 ||
-             (p->locked && p->wantToLock && sqlite3_mutex_held(p->pBt->mutex)));
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager *pPager, int level, int bFullFsync){
+  pPager->noSync =  (level==1 || pPager->tempFile) ?1:0;
+  pPager->fullSync = (level==3 && !pPager->tempFile) ?1:0;
+  pPager->sync_flags = (bFullFsync?SQLITE_SYNC_FULL:SQLITE_SYNC_NORMAL);
+  if( pPager->noSync ) pPager->needSync = 0;
 }
 #endif
 
-
-#ifndef SQLITE_OMIT_INCRBLOB
 /*
-** Enter and leave a mutex on a Btree given a cursor owned by that
-** Btree.  These entry points are used by incremental I/O and can be
-** omitted if that module is not used.
+** The following global variable is incremented whenever the library
+** attempts to open a temporary file.  This information is used for
+** testing and analysis only.  
 */
-SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor *pCur){
-  sqlite3BtreeEnter(pCur->pBtree);
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_opentemp_count = 0;
+#endif
+
+/*
+** Open a temporary file.
+**
+** Write the file descriptor into *pFile. Return SQLITE_OK on success 
+** or some other error code if we fail. The OS will automatically 
+** delete the temporary file when it is closed.
+**
+** The flags passed to the VFS layer xOpen() call are those specified
+** by parameter vfsFlags ORed with the following:
+**
+**     SQLITE_OPEN_READWRITE
+**     SQLITE_OPEN_CREATE
+**     SQLITE_OPEN_EXCLUSIVE
+**     SQLITE_OPEN_DELETEONCLOSE
+*/
+static int pagerOpentemp(
+  Pager *pPager,        /* The pager object */
+  sqlite3_file *pFile,  /* Write the file descriptor here */
+  int vfsFlags          /* Flags passed through to the VFS */
+){
+  int rc;               /* Return code */
+
+#ifdef SQLITE_TEST
+  sqlite3_opentemp_count++;  /* Used for testing and analysis only */
+#endif
+
+  vfsFlags |=  SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE |
+            SQLITE_OPEN_EXCLUSIVE | SQLITE_OPEN_DELETEONCLOSE;
+  rc = sqlite3OsOpen(pPager->pVfs, 0, pFile, vfsFlags, 0);
+  assert( rc!=SQLITE_OK || isOpen(pFile) );
+  return rc;
 }
-SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor *pCur){
-  sqlite3BtreeLeave(pCur->pBtree);
+
+/*
+** Set the busy handler function.
+**
+** The pager invokes the busy-handler if sqlite3OsLock() returns 
+** SQLITE_BUSY when trying to upgrade from no-lock to a SHARED lock,
+** or when trying to upgrade from a RESERVED lock to an EXCLUSIVE 
+** lock. It does *not* invoke the busy handler when upgrading from
+** SHARED to RESERVED, or when upgrading from SHARED to EXCLUSIVE
+** (which occurs during hot-journal rollback). Summary:
+**
+**   Transition                        | Invokes xBusyHandler
+**   --------------------------------------------------------
+**   NO_LOCK       -> SHARED_LOCK      | Yes
+**   SHARED_LOCK   -> RESERVED_LOCK    | No
+**   SHARED_LOCK   -> EXCLUSIVE_LOCK   | No
+**   RESERVED_LOCK -> EXCLUSIVE_LOCK   | Yes
+**
+** If the busy-handler callback returns non-zero, the lock is 
+** retried. If it returns zero, then the SQLITE_BUSY error is
+** returned to the caller of the pager API function.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(
+  Pager *pPager,                       /* Pager object */
+  int (*xBusyHandler)(void *),         /* Pointer to busy-handler function */
+  void *pBusyHandlerArg                /* Argument to pass to xBusyHandler */
+){  
+  pPager->xBusyHandler = xBusyHandler;
+  pPager->pBusyHandlerArg = pBusyHandlerArg;
 }
-#endif /* SQLITE_OMIT_INCRBLOB */
 
+/*
+** Report the current page size and number of reserved bytes back
+** to the codec.
+*/
+#ifdef SQLITE_HAS_CODEC
+static void pagerReportSize(Pager *pPager){
+  if( pPager->xCodecSizeChng ){
+    pPager->xCodecSizeChng(pPager->pCodec, pPager->pageSize,
+                           (int)pPager->nReserve);
+  }
+}
+#else
+# define pagerReportSize(X)     /* No-op if we do not support a codec */
+#endif
 
 /*
-** Enter the mutex on every Btree associated with a database
-** connection.  This is needed (for example) prior to parsing
-** a statement since we will be comparing table and column names
-** against all schemas and we do not want those schemas being
-** reset out from under us.
+** Change the page size used by the Pager object. The new page size 
+** is passed in *pPageSize.
 **
-** There is a corresponding leave-all procedures.
+** If the pager is in the error state when this function is called, it
+** is a no-op. The value returned is the error state error code (i.e. 
+** one of SQLITE_IOERR, SQLITE_CORRUPT or SQLITE_FULL).
 **
-** Enter the mutexes in accending order by BtShared pointer address
-** to avoid the possibility of deadlock when two threads with
-** two or more btrees in common both try to lock all their btrees
-** at the same instant.
+** Otherwise, if all of the following are true:
+**
+**   * the new page size (value of *pPageSize) is valid (a power 
+**     of two between 512 and SQLITE_MAX_PAGE_SIZE, inclusive), and
+**
+**   * there are no outstanding page references, and
+**
+**   * the database is either not an in-memory database or it is
+**     an in-memory database that currently consists of zero pages.
+**
+** then the pager object page size is set to *pPageSize.
+**
+** If the page size is changed, then this function uses sqlite3PagerMalloc() 
+** to obtain a new Pager.pTmpSpace buffer. If this allocation attempt 
+** fails, SQLITE_NOMEM is returned and the page size remains unchanged. 
+** In all other cases, SQLITE_OK is returned.
+**
+** If the page size is not changed, either because one of the enumerated
+** conditions above is not true, the pager was in error state when this
+** function was called, or because the memory allocation attempt failed, 
+** then *pPageSize is set to the old, retained page size before returning.
 */
-SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3 *db){
-  int i;
-  Btree *p, *pLater;
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(i=0; i<db->nDb; i++){
-    p = db->aDb[i].pBt;
-    if( p && p->sharable ){
-      p->wantToLock++;
-      if( !p->locked ){
-        assert( p->wantToLock==1 );
-        while( p->pPrev ) p = p->pPrev;
-        while( p->locked && p->pNext ) p = p->pNext;
-        for(pLater = p->pNext; pLater; pLater=pLater->pNext){
-          if( pLater->locked ){
-            sqlite3_mutex_leave(pLater->pBt->mutex);
-            pLater->locked = 0;
-          }
-        }
-        while( p ){
-          sqlite3_mutex_enter(p->pBt->mutex);
-          p->locked++;
-          p = p->pNext;
-        }
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize, int nReserve){
+  int rc = pPager->errCode;
+
+  if( rc==SQLITE_OK ){
+    u16 pageSize = *pPageSize;
+    assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
+    if( (pPager->memDb==0 || pPager->dbSize==0)
+     && sqlite3PcacheRefCount(pPager->pPCache)==0 
+     && pageSize && pageSize!=pPager->pageSize 
+    ){
+      char *pNew = (char *)sqlite3PageMalloc(pageSize);
+      if( !pNew ){
+        rc = SQLITE_NOMEM;
+      }else{
+        pager_reset(pPager);
+        pPager->pageSize = pageSize;
+        sqlite3PageFree(pPager->pTmpSpace);
+        pPager->pTmpSpace = pNew;
+        sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
       }
     }
+    *pPageSize = (u16)pPager->pageSize;
+    if( nReserve<0 ) nReserve = pPager->nReserve;
+    assert( nReserve>=0 && nReserve<1000 );
+    pPager->nReserve = (i16)nReserve;
+    pagerReportSize(pPager);
   }
+  return rc;
 }
-SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3 *db){
-  int i;
-  Btree *p;
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(i=0; i<db->nDb; i++){
-    p = db->aDb[i].pBt;
-    if( p && p->sharable ){
-      assert( p->wantToLock>0 );
-      p->wantToLock--;
-      if( p->wantToLock==0 ){
-        assert( p->locked );
-        sqlite3_mutex_leave(p->pBt->mutex);
-        p->locked = 0;
-      }
-    }
-  }
+
+/*
+** Return a pointer to the "temporary page" buffer held internally
+** by the pager.  This is a buffer that is big enough to hold the
+** entire content of a database page.  This buffer is used internally
+** during rollback and will be overwritten whenever a rollback
+** occurs.  But other modules are free to use it too, as long as
+** no rollbacks are happening.
+*/
+SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager *pPager){
+  return pPager->pTmpSpace;
 }
 
-#ifndef NDEBUG
 /*
-** Return true if the current thread holds the database connection
-** mutex and all required BtShared mutexes.
+** Attempt to set the maximum database page count if mxPage is positive. 
+** Make no changes if mxPage is zero or negative.  And never reduce the
+** maximum page count below the current size of the database.
 **
-** This routine is used inside assert() statements only.
+** Regardless of mxPage, return the current maximum page count.
 */
-SQLITE_PRIVATE int sqlite3BtreeHoldsAllMutexes(sqlite3 *db){
-  int i;
-  if( !sqlite3_mutex_held(db->mutex) ){
-    return 0;
-  }
-  for(i=0; i<db->nDb; i++){
-    Btree *p;
-    p = db->aDb[i].pBt;
-    if( p && p->sharable &&
-         (p->wantToLock==0 || !sqlite3_mutex_held(p->pBt->mutex)) ){
-      return 0;
-    }
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
+  if( mxPage>0 ){
+    pPager->mxPgno = mxPage;
   }
-  return 1;
+  sqlite3PagerPagecount(pPager, 0);
+  return pPager->mxPgno;
 }
-#endif /* NDEBUG */
 
 /*
-** Potentially dd a new Btree pointer to a BtreeMutexArray.
-** Really only add the Btree if it can possibly be shared with
-** another database connection.
-**
-** The Btrees are kept in sorted order by pBtree->pBt.  That
-** way when we go to enter all the mutexes, we can enter them
-** in order without every having to backup and retry and without
-** worrying about deadlock.
+** The following set of routines are used to disable the simulated
+** I/O error mechanism.  These routines are used to avoid simulated
+** errors in places where we do not care about errors.
 **
-** The number of shared btrees will always be small (usually 0 or 1)
-** so an insertion sort is an adequate algorithm here.
+** Unless -DSQLITE_TEST=1 is used, these routines are all no-ops
+** and generate no code.
 */
-SQLITE_PRIVATE void sqlite3BtreeMutexArrayInsert(BtreeMutexArray *pArray, Btree *pBtree){
-  int i, j;
-  BtShared *pBt;
-  if( pBtree==0 || pBtree->sharable==0 ) return;
-#ifndef NDEBUG
-  {
-    for(i=0; i<pArray->nMutex; i++){
-      assert( pArray->aBtree[i]!=pBtree );
-    }
-  }
+#ifdef SQLITE_TEST
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_hit;
+static int saved_cnt;
+void disable_simulated_io_errors(void){
+  saved_cnt = sqlite3_io_error_pending;
+  sqlite3_io_error_pending = -1;
+}
+void enable_simulated_io_errors(void){
+  sqlite3_io_error_pending = saved_cnt;
+}
+#else
+# define disable_simulated_io_errors()
+# define enable_simulated_io_errors()
 #endif
-  assert( pArray->nMutex>=0 );
-  assert( pArray->nMutex<sizeof(pArray->aBtree)/sizeof(pArray->aBtree[0])-1 );
-  pBt = pBtree->pBt;
-  for(i=0; i<pArray->nMutex; i++){
-    assert( pArray->aBtree[i]!=pBtree );
-    if( pArray->aBtree[i]->pBt>pBt ){
-      for(j=pArray->nMutex; j>i; j--){
-        pArray->aBtree[j] = pArray->aBtree[j-1];
-      }
-      pArray->aBtree[i] = pBtree;
-      pArray->nMutex++;
-      return;
+
+/*
+** Read the first N bytes from the beginning of the file into memory
+** that pDest points to. 
+**
+** If the pager was opened on a transient file (zFilename==""), or
+** opened on a file less than N bytes in size, the output buffer is
+** zeroed and SQLITE_OK returned. The rationale for this is that this 
+** function is used to read database headers, and a new transient or
+** zero sized database has a header than consists entirely of zeroes.
+**
+** If any IO error apart from SQLITE_IOERR_SHORT_READ is encountered,
+** the error code is returned to the caller and the contents of the
+** output buffer undefined.
+*/
+SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager *pPager, int N, unsigned char *pDest){
+  int rc = SQLITE_OK;
+  memset(pDest, 0, N);
+  assert( isOpen(pPager->fd) || pPager->tempFile );
+  if( isOpen(pPager->fd) ){
+    IOTRACE(("DBHDR %p 0 %d\n", pPager, N))
+    rc = sqlite3OsRead(pPager->fd, pDest, N, 0);
+    if( rc==SQLITE_IOERR_SHORT_READ ){
+      rc = SQLITE_OK;
     }
   }
-  pArray->aBtree[pArray->nMutex++] = pBtree;
+  return rc;
 }
 
 /*
-** Enter the mutex of every btree in the array.  This routine is
-** called at the beginning of sqlite3VdbeExec().  The mutexes are
-** exited at the end of the same function.
+** Return the total number of pages in the database file associated 
+** with pPager. Normally, this is calculated as (<db file size>/<page-size>).
+** However, if the file is between 1 and <page-size> bytes in size, then 
+** this is considered a 1 page file.
+**
+** If the pager is in error state when this function is called, then the
+** error state error code is returned and *pnPage left unchanged. Or,
+** if the file system has to be queried for the size of the file and
+** the query attempt returns an IO error, the IO error code is returned
+** and *pnPage is left unchanged.
+**
+** Otherwise, if everything is successful, then SQLITE_OK is returned
+** and *pnPage is set to the number of pages in the database.
 */
-SQLITE_PRIVATE void sqlite3BtreeMutexArrayEnter(BtreeMutexArray *pArray){
-  int i;
-  for(i=0; i<pArray->nMutex; i++){
-    Btree *p = pArray->aBtree[i];
-    /* Some basic sanity checking */
-    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
-    assert( !p->locked || p->wantToLock>0 );
+SQLITE_PRIVATE int sqlite3PagerPagecount(Pager *pPager, int *pnPage){
+  Pgno nPage;               /* Value to return via *pnPage */
 
-    /* We should already hold a lock on the database connection */
-    assert( sqlite3_mutex_held(p->db->mutex) );
+  /* If the pager is already in the error state, return the error code. */
+  if( pPager->errCode ){
+    return pPager->errCode;
+  }
 
-    p->wantToLock++;
-    if( !p->locked && p->sharable ){
-      sqlite3_mutex_enter(p->pBt->mutex);
-      p->locked = 1;
+  /* Determine the number of pages in the file. Store this in nPage. */
+  if( pPager->dbSizeValid ){
+    nPage = pPager->dbSize;
+  }else{
+    int rc;                 /* Error returned by OsFileSize() */
+    i64 n = 0;              /* File size in bytes returned by OsFileSize() */
+
+    assert( isOpen(pPager->fd) || pPager->tempFile );
+    if( isOpen(pPager->fd) && (0 != (rc = sqlite3OsFileSize(pPager->fd, &n))) ){
+      pager_error(pPager, rc);
+      return rc;
+    }
+    if( n>0 && n<pPager->pageSize ){
+      nPage = 1;
+    }else{
+      nPage = (Pgno)(n / pPager->pageSize);
     }
+    if( pPager->state!=PAGER_UNLOCK ){
+      pPager->dbSize = nPage;
+      pPager->dbFileSize = nPage;
+      pPager->dbSizeValid = 1;
+    }
+  }
+
+  /* If the current number of pages in the file is greater than the 
+  ** configured maximum pager number, increase the allowed limit so
+  ** that the file can be read.
+  */
+  if( nPage>pPager->mxPgno ){
+    pPager->mxPgno = (Pgno)nPage;
+  }
+
+  /* Set the output variable and return SQLITE_OK */
+  if( pnPage ){
+    *pnPage = nPage;
   }
+  return SQLITE_OK;
 }
 
+
 /*
-** Leave the mutex of every btree in the group.
+** Try to obtain a lock of type locktype on the database file. If
+** a similar or greater lock is already held, this function is a no-op
+** (returning SQLITE_OK immediately).
+**
+** Otherwise, attempt to obtain the lock using sqlite3OsLock(). Invoke 
+** the busy callback if the lock is currently not available. Repeat 
+** until the busy callback returns false or until the attempt to 
+** obtain the lock succeeds.
+**
+** Return SQLITE_OK on success and an error code if we cannot obtain
+** the lock. If the lock is obtained successfully, set the Pager.state 
+** variable to locktype before returning.
 */
-SQLITE_PRIVATE void sqlite3BtreeMutexArrayLeave(BtreeMutexArray *pArray){
-  int i;
-  for(i=0; i<pArray->nMutex; i++){
-    Btree *p = pArray->aBtree[i];
-    /* Some basic sanity checking */
-    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
-    assert( p->locked || !p->sharable );
-    assert( p->wantToLock>0 );
+static int pager_wait_on_lock(Pager *pPager, int locktype){
+  int rc;                              /* Return code */
 
-    /* We should already hold a lock on the database connection */
-    assert( sqlite3_mutex_held(p->db->mutex) );
+  /* The OS lock values must be the same as the Pager lock values */
+  assert( PAGER_SHARED==SHARED_LOCK );
+  assert( PAGER_RESERVED==RESERVED_LOCK );
+  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
 
-    p->wantToLock--;
-    if( p->wantToLock==0 && p->locked ){
-      sqlite3_mutex_leave(p->pBt->mutex);
-      p->locked = 0;
+  /* If the file is currently unlocked then the size must be unknown */
+  assert( pPager->state>=PAGER_SHARED || pPager->dbSizeValid==0 );
+
+  /* Check that this is either a no-op (because the requested lock is 
+  ** already held, or one of the transistions that the busy-handler
+  ** may be invoked during, according to the comment above
+  ** sqlite3PagerSetBusyhandler().
+  */
+  assert( (pPager->state>=locktype)
+       || (pPager->state==PAGER_UNLOCK && locktype==PAGER_SHARED)
+       || (pPager->state==PAGER_RESERVED && locktype==PAGER_EXCLUSIVE)
+  );
+
+  if( pPager->state>=locktype ){
+    rc = SQLITE_OK;
+  }else{
+    do {
+      rc = sqlite3OsLock(pPager->fd, locktype);
+    }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
+    if( rc==SQLITE_OK ){
+      pPager->state = (u8)locktype;
+      IOTRACE(("LOCK %p %d\n", pPager, locktype))
     }
   }
+  return rc;
 }
 
-
-#endif  /* SQLITE_THREADSAFE && !SQLITE_OMIT_SHARED_CACHE */
-
-/************** End of btmutex.c *********************************************/
-/************** Begin file btree.c *******************************************/
 /*
-** 2004 April 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Function assertTruncateConstraint(pPager) checks that one of the 
+** following is true for all dirty pages currently in the page-cache:
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+**   a) The page number is less than or equal to the size of the 
+**      current database image, in pages, OR
 **
-*************************************************************************
-** $Id: btree.c,v 1.458 2008/05/09 16:57:51 danielk1977 Exp $
+**   b) if the page content were written at this time, it would not
+**      be necessary to write the current content out to the sub-journal
+**      (as determined by function subjRequiresPage()).
 **
-** This file implements a external (disk-based) database using BTrees.
-** See the header comment on "btreeInt.h" for additional information.
-** Including a description of file format and an overview of operation.
+** If the condition asserted by this function were not true, and the
+** dirty page were to be discarded from the cache via the pagerStress()
+** routine, pagerStress() would not write the current page content to
+** the database file. If a savepoint transaction were rolled back after
+** this happened, the correct behaviour would be to restore the current
+** content of the page. However, since this content is not present in either
+** the database file or the portion of the rollback journal and 
+** sub-journal rolled back the content could not be restored and the
+** database image would become corrupt. It is therefore fortunate that 
+** this circumstance cannot arise.
 */
+#if defined(SQLITE_DEBUG)
+static void assertTruncateConstraintCb(PgHdr *pPg){
+  assert( pPg->flags&PGHDR_DIRTY );
+  assert( !subjRequiresPage(pPg) || pPg->pgno<=pPg->pPager->dbSize );
+}
+static void assertTruncateConstraint(Pager *pPager){
+  sqlite3PcacheIterateDirty(pPager->pPCache, assertTruncateConstraintCb);
+}
+#else
+# define assertTruncateConstraint(pPager)
+#endif
 
 /*
-** The header string that appears at the beginning of every
-** SQLite database.
+** Truncate the in-memory database file image to nPage pages. This 
+** function does not actually modify the database file on disk. It 
+** just sets the internal state of the pager object so that the 
+** truncation will be done when the current transaction is committed.
 */
-static const char zMagicHeader[] = SQLITE_FILE_HEADER;
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
+  assert( pPager->dbSizeValid );
+  assert( pPager->dbSize>=nPage );
+  assert( pPager->state>=PAGER_RESERVED );
+  pPager->dbSize = nPage;
+  assertTruncateConstraint(pPager);
+}
 
 /*
-** Set this global variable to 1 to enable tracing using the TRACE
-** macro.
+** Shutdown the page cache.  Free all memory and close all files.
+**
+** If a transaction was in progress when this routine is called, that
+** transaction is rolled back.  All outstanding pages are invalidated
+** and their memory is freed.  Any attempt to use a page associated
+** with this page cache after this function returns will likely
+** result in a coredump.
+**
+** This function always succeeds. If a transaction is active an attempt
+** is made to roll it back. If an error occurs during the rollback 
+** a hot journal may be left in the filesystem but no error is returned
+** to the caller.
 */
-#if SQLITE_TEST
-int sqlite3BtreeTrace=0;  /* True to enable tracing */
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager){
+  disable_simulated_io_errors();
+  sqlite3BeginBenignMalloc();
+  pPager->errCode = 0;
+  pPager->exclusiveMode = 0;
+  pager_reset(pPager);
+  if( MEMDB ){
+    pager_unlock(pPager);
+  }else{
+    /* Set Pager.journalHdr to -1 for the benefit of the pager_playback() 
+    ** call which may be made from within pagerUnlockAndRollback(). If it
+    ** is not -1, then the unsynced portion of an open journal file may
+    ** be played back into the database. If a power failure occurs while
+    ** this is happening, the database may become corrupt.
+    */
+    pPager->journalHdr = -1;
+    pagerUnlockAndRollback(pPager);
+  }
+  sqlite3EndBenignMalloc();
+  enable_simulated_io_errors();
+  PAGERTRACE(("CLOSE %d\n", PAGERID(pPager)));
+  IOTRACE(("CLOSE %p\n", pPager))
+  sqlite3OsClose(pPager->fd);
+  sqlite3PageFree(pPager->pTmpSpace);
+  sqlite3PcacheClose(pPager->pPCache);
+
+#ifdef SQLITE_HAS_CODEC
+  if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
 #endif
 
+  assert( !pPager->aSavepoint && !pPager->pInJournal );
+  assert( !isOpen(pPager->jfd) && !isOpen(pPager->sjfd) );
 
+  sqlite3_free(pPager);
+  return SQLITE_OK;
+}
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
+#if !defined(NDEBUG) || defined(SQLITE_TEST)
 /*
-** A flag to indicate whether or not shared cache is enabled.  Also,
-** a list of BtShared objects that are eligible for participation
-** in shared cache.  The variables have file scope during normal builds,
-** but the test harness needs to access these variables so we make them
-** global for test builds.
+** Return the page number for page pPg.
 */
-#ifdef SQLITE_TEST
-SQLITE_PRIVATE BtShared *sqlite3SharedCacheList = 0;
-SQLITE_PRIVATE int sqlite3SharedCacheEnabled = 0;
-#else
-static BtShared *sqlite3SharedCacheList = 0;
-static int sqlite3SharedCacheEnabled = 0;
+SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage *pPg){
+  return pPg->pgno;
+}
 #endif
-#endif /* SQLITE_OMIT_SHARED_CACHE */
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** Enable or disable the shared pager and schema features.
-**
-** This routine has no effect on existing database connections.
-** The shared cache setting effects only future calls to
-** sqlite3_open(), sqlite3_open16(), or sqlite3_open_v2().
+** Increment the reference count for page pPg.
 */
-SQLITE_API int sqlite3_enable_shared_cache(int enable){
-  sqlite3SharedCacheEnabled = enable;
-  return SQLITE_OK;
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage *pPg){
+  sqlite3PcacheRef(pPg);
 }
-#endif
-
 
 /*
-** Forward declaration
+** Sync the journal. In other words, make sure all the pages that have
+** been written to the journal have actually reached the surface of the
+** disk and can be restored in the event of a hot-journal rollback.
+**
+** If the Pager.needSync flag is not set, then this function is a
+** no-op. Otherwise, the actions required depend on the journal-mode
+** and the device characteristics of the the file-system, as follows:
+**
+**   * If the journal file is an in-memory journal file, no action need
+**     be taken.
+**
+**   * Otherwise, if the device does not support the SAFE_APPEND property,
+**     then the nRec field of the most recently written journal header
+**     is updated to contain the number of journal records that have
+**     been written following it. If the pager is operating in full-sync
+**     mode, then the journal file is synced before this field is updated.
+**
+**   * If the device does not support the SEQUENTIAL property, then 
+**     journal file is synced.
+**
+** Or, in pseudo-code:
+**
+**   if( NOT <in-memory journal> ){
+**     if( NOT SAFE_APPEND ){
+**       if( <full-sync mode> ) xSync(<journal file>);
+**       <update nRec field>
+**     } 
+**     if( NOT SEQUENTIAL ) xSync(<journal file>);
+**   }
+**
+** The Pager.needSync flag is never be set for temporary files, or any
+** file operating in no-sync mode (Pager.noSync set to non-zero).
+**
+** If successful, this routine clears the PGHDR_NEED_SYNC flag of every 
+** page currently held in memory before returning SQLITE_OK. If an IO
+** error is encountered, then the IO error code is returned to the caller.
 */
-static int checkReadLocks(Btree*,Pgno,BtCursor*);
+static int syncJournal(Pager *pPager){
+  if( pPager->needSync ){
+    assert( !pPager->tempFile );
+    if( pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
+      int rc;                              /* Return code */
+      const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+      assert( isOpen(pPager->jfd) );
 
+      if( 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+        /* This block deals with an obscure problem. If the last connection
+        ** that wrote to this database was operating in persistent-journal
+        ** mode, then the journal file may at this point actually be larger
+        ** than Pager.journalOff bytes. If the next thing in the journal
+        ** file happens to be a journal-header (written as part of the
+        ** previous connections transaction), and a crash or power-failure 
+        ** occurs after nRec is updated but before this connection writes 
+        ** anything else to the journal file (or commits/rolls back its 
+        ** transaction), then SQLite may become confused when doing the 
+        ** hot-journal rollback following recovery. It may roll back all
+        ** of this connections data, then proceed to rolling back the old,
+        ** out-of-date data that follows it. Database corruption.
+        **
+        ** To work around this, if the journal file does appear to contain
+        ** a valid header following Pager.journalOff, then write a 0x00
+        ** byte to the start of it to prevent it from being recognized.
+        **
+        ** Variable iNextHdrOffset is set to the offset at which this
+        ** problematic header will occur, if it exists. aMagic is used 
+        ** as a temporary buffer to inspect the first couple of bytes of
+        ** the potential journal header.
+        */
+        i64 iNextHdrOffset;
+        u8 aMagic[8];
+	u8 zHeader[sizeof(aJournalMagic)+4];
+
+	memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+	put32bits(&zHeader[sizeof(aJournalMagic)], pPager->nRec);
+
+        iNextHdrOffset = journalHdrOffset(pPager);
+        rc = sqlite3OsRead(pPager->jfd, aMagic, 8, iNextHdrOffset);
+        if( rc==SQLITE_OK && 0==memcmp(aMagic, aJournalMagic, 8) ){
+          static const u8 zerobyte = 0;
+          rc = sqlite3OsWrite(pPager->jfd, &zerobyte, 1, iNextHdrOffset);
+        }
+        if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
+          return rc;
+        }
 
-#ifdef SQLITE_OMIT_SHARED_CACHE
-  /*
-  ** The functions queryTableLock(), lockTable() and unlockAllTables()
-  ** manipulate entries in the BtShared.pLock linked list used to store
-  ** shared-cache table level locks. If the library is compiled with the
-  ** shared-cache feature disabled, then there is only ever one user
-  ** of each BtShared structure and so this locking is not necessary. 
-  ** So define the lock related functions as no-ops.
-  */
-  #define queryTableLock(a,b,c) SQLITE_OK
-  #define lockTable(a,b,c) SQLITE_OK
-  #define unlockAllTables(a)
-#endif
+        /* Write the nRec value into the journal file header. If in
+        ** full-synchronous mode, sync the journal first. This ensures that
+        ** all data has really hit the disk before nRec is updated to mark
+        ** it as a candidate for rollback.
+        **
+        ** This is not required if the persistent media supports the
+        ** SAFE_APPEND property. Because in this case it is not possible 
+        ** for garbage data to be appended to the file, the nRec field
+        ** is populated with 0xFFFFFFFF when the journal header is written
+        ** and never needs to be updated.
+        */
+        if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+          PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+          IOTRACE(("JSYNC %p\n", pPager))
+          rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags);
+          if( rc!=SQLITE_OK ) return rc;
+        }
+        IOTRACE(("JHDR %p %lld\n", pPager, pPager->journalHdr));
+        rc = sqlite3OsWrite(
+            pPager->jfd, zHeader, sizeof(zHeader), pPager->journalHdr
+	);
+        if( rc!=SQLITE_OK ) return rc;
+      }
+      if( 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+        PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+        IOTRACE(("JSYNC %p\n", pPager))
+        rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags| 
+          (pPager->sync_flags==SQLITE_SYNC_FULL?SQLITE_SYNC_DATAONLY:0)
+        );
+        if( rc!=SQLITE_OK ) return rc;
+      }
+    }
+
+    /* The journal file was just successfully synced. Set Pager.needSync 
+    ** to zero and clear the PGHDR_NEED_SYNC flag on all pagess.
+    */
+    pPager->needSync = 0;
+    pPager->journalStarted = 1;
+    sqlite3PcacheClearSyncFlags(pPager->pPCache);
+  }
+
+  return SQLITE_OK;
+}
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** Query to see if btree handle p may obtain a lock of type eLock 
-** (READ_LOCK or WRITE_LOCK) on the table with root-page iTab. Return
-** SQLITE_OK if the lock may be obtained (by calling lockTable()), or
-** SQLITE_LOCKED if not.
+** The argument is the first in a linked list of dirty pages connected
+** by the PgHdr.pDirty pointer. This function writes each one of the
+** in-memory pages in the list to the database file. The argument may
+** be NULL, representing an empty list. In this case this function is
+** a no-op.
+**
+** The pager must hold at least a RESERVED lock when this function
+** is called. Before writing anything to the database file, this lock
+** is upgraded to an EXCLUSIVE lock. If the lock cannot be obtained,
+** SQLITE_BUSY is returned and no data is written to the database file.
+** 
+** If the pager is a temp-file pager and the actual file-system file
+** is not yet open, it is created and opened before any data is 
+** written out.
+**
+** Once the lock has been upgraded and, if necessary, the file opened,
+** the pages are written out to the database file in list order. Writing
+** a page is skipped if it meets either of the following criteria:
+**
+**   * The page number is greater than Pager.dbSize, or
+**   * The PGHDR_DONT_WRITE flag is set on the page.
+**
+** If writing out a page causes the database file to grow, Pager.dbFileSize
+** is updated accordingly. If page 1 is written out, then the value cached
+** in Pager.dbFileVers[] is updated to match the new value stored in
+** the database file.
+**
+** If everything is successful, SQLITE_OK is returned. If an IO error 
+** occurs, an IO error code is returned. Or, if the EXCLUSIVE lock cannot
+** be obtained, SQLITE_BUSY is returned.
 */
-static int queryTableLock(Btree *p, Pgno iTab, u8 eLock){
-  BtShared *pBt = p->pBt;
-  BtLock *pIter;
-
-  assert( sqlite3BtreeHoldsMutex(p) );
-  
-  /* This is a no-op if the shared-cache is not enabled */
-  if( !p->sharable ){
-    return SQLITE_OK;
-  }
+static int pager_write_pagelist(PgHdr *pList){
+  Pager *pPager;                       /* Pager object */
+  int rc;                              /* Return code */
 
-  /* If some other connection is holding an exclusive lock, the
-  ** requested lock may not be obtained.
-  */
-  if( pBt->pExclusive && pBt->pExclusive!=p ){
-    return SQLITE_LOCKED;
-  }
+  if( NEVER(pList==0) ) return SQLITE_OK;
+  pPager = pList->pPager;
 
-  /* This (along with lockTable()) is where the ReadUncommitted flag is
-  ** dealt with. If the caller is querying for a read-lock and the flag is
-  ** set, it is unconditionally granted - even if there are write-locks
-  ** on the table. If a write-lock is requested, the ReadUncommitted flag
-  ** is not considered.
+  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
+  ** database file. If there is already an EXCLUSIVE lock, the following
+  ** call is a no-op.
   **
-  ** In function lockTable(), if a read-lock is demanded and the 
-  ** ReadUncommitted flag is set, no entry is added to the locks list 
-  ** (BtShared.pLock).
+  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
+  ** through an intermediate state PENDING.   A PENDING lock prevents new
+  ** readers from attaching to the database but is unsufficient for us to
+  ** write.  The idea of a PENDING lock is to prevent new readers from
+  ** coming in while we wait for existing readers to clear.
   **
-  ** To summarize: If the ReadUncommitted flag is set, then read cursors do
-  ** not create or respect table locks. The locking procedure for a 
-  ** write-cursor does not change.
+  ** While the pager is in the RESERVED state, the original database file
+  ** is unchanged and we can rollback without having to playback the
+  ** journal into the original database file.  Once we transition to
+  ** EXCLUSIVE, it means the database file has been changed and any rollback
+  ** will require a journal playback.
   */
-  if( 
-    !p->db || 
-    0==(p->db->flags&SQLITE_ReadUncommitted) || 
-    eLock==WRITE_LOCK ||
-    iTab==MASTER_ROOT
-  ){
-    for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
-      if( pIter->pBtree!=p && pIter->iTable==iTab && 
-          (pIter->eLock!=eLock || eLock!=READ_LOCK) ){
-        return SQLITE_LOCKED;
+  assert( pPager->state>=PAGER_RESERVED );
+  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+
+  /* If the file is a temp-file has not yet been opened, open it now. It
+  ** is not possible for rc to be other than SQLITE_OK if this branch
+  ** is taken, as pager_wait_on_lock() is a no-op for temp-files.
+  */
+  if( !isOpen(pPager->fd) ){
+    assert( pPager->tempFile && rc==SQLITE_OK );
+    rc = pagerOpentemp(pPager, pPager->fd, pPager->vfsFlags);
+  }
+
+  while( rc==SQLITE_OK && pList ){
+    Pgno pgno = pList->pgno;
+
+    /* If there are dirty pages in the page cache with page numbers greater
+    ** than Pager.dbSize, this means sqlite3PagerTruncateImage() was called to
+    ** make the file smaller (presumably by auto-vacuum code). Do not write
+    ** any such pages to the file.
+    **
+    ** Also, do not write out any page that has the PGHDR_DONT_WRITE flag
+    ** set (set by sqlite3PagerDontWrite()).
+    */
+    if( pgno<=pPager->dbSize && 0==(pList->flags&PGHDR_DONT_WRITE) ){
+      i64 offset = (pgno-1)*(i64)pPager->pageSize;   /* Offset to write */
+      char *pData;                                   /* Data to write */    
+
+      /* Encode the database */
+      CODEC2(pPager, pList->pData, pgno, 6, return SQLITE_NOMEM, pData);
+
+      /* Write out the page data. */
+      rc = sqlite3OsWrite(pPager->fd, pData, pPager->pageSize, offset);
+
+      /* If page 1 was just written, update Pager.dbFileVers to match
+      ** the value now stored in the database file. If writing this 
+      ** page caused the database file to grow, update dbFileSize. 
+      */
+      if( pgno==1 ){
+        memcpy(&pPager->dbFileVers, &pData[24], sizeof(pPager->dbFileVers));
+      }
+      if( pgno>pPager->dbFileSize ){
+        pPager->dbFileSize = pgno;
       }
+
+      /* Update any backup objects copying the contents of this pager. */
+      sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)pList->pData);
+
+      PAGERTRACE(("STORE %d page %d hash(%08x)\n",
+                   PAGERID(pPager), pgno, pager_pagehash(pList)));
+      IOTRACE(("PGOUT %p %d\n", pPager, pgno));
+      PAGER_INCR(sqlite3_pager_writedb_count);
+      PAGER_INCR(pPager->nWrite);
+    }else{
+      PAGERTRACE(("NOSTORE %d page %d\n", PAGERID(pPager), pgno));
     }
+#ifdef SQLITE_CHECK_PAGES
+    pList->pageHash = pager_pagehash(pList);
+#endif
+    pList = pList->pDirty;
   }
-  return SQLITE_OK;
+
+  return rc;
 }
-#endif /* !SQLITE_OMIT_SHARED_CACHE */
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** Add a lock on the table with root-page iTable to the shared-btree used
-** by Btree handle p. Parameter eLock must be either READ_LOCK or 
-** WRITE_LOCK.
+** Append a record of the current state of page pPg to the sub-journal. 
+** It is the callers responsibility to use subjRequiresPage() to check 
+** that it is really required before calling this function.
+**
+** If successful, set the bit corresponding to pPg->pgno in the bitvecs
+** for all open savepoints before returning.
 **
-** SQLITE_OK is returned if the lock is added successfully. SQLITE_BUSY and
-** SQLITE_NOMEM may also be returned.
+** This function returns SQLITE_OK if everything is successful, an IO
+** error code if the attempt to write to the sub-journal fails, or 
+** SQLITE_NOMEM if a malloc fails while setting a bit in a savepoint
+** bitvec.
 */
-static int lockTable(Btree *p, Pgno iTable, u8 eLock){
-  BtShared *pBt = p->pBt;
-  BtLock *pLock = 0;
-  BtLock *pIter;
-
-  assert( sqlite3BtreeHoldsMutex(p) );
+static int subjournalPage(PgHdr *pPg){
+  int rc = SQLITE_OK;
+  Pager *pPager = pPg->pPager;
+  if( isOpen(pPager->sjfd) ){
+    void *pData = pPg->pData;
+    i64 offset = pPager->nSubRec*(4+pPager->pageSize);
+    char *pData2;
 
-  /* This is a no-op if the shared-cache is not enabled */
-  if( !p->sharable ){
-    return SQLITE_OK;
+    CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
+    PAGERTRACE(("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno));
+  
+    assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
+    rc = write32bits(pPager->sjfd, offset, pPg->pgno);
+    if( rc==SQLITE_OK ){
+      rc = sqlite3OsWrite(pPager->sjfd, pData2, pPager->pageSize, offset+4);
+    }
+  }
+  if( rc==SQLITE_OK ){
+    pPager->nSubRec++;
+    assert( pPager->nSavepoint>0 );
+    rc = addToSavepointBitvecs(pPager, pPg->pgno);
   }
+  return rc;
+}
+
 
-  assert( SQLITE_OK==queryTableLock(p, iTable, eLock) );
+/*
+** This function is called by the pcache layer when it has reached some
+** soft memory limit. The first argument is a pointer to a Pager object
+** (cast as a void*). The pager is always 'purgeable' (not an in-memory
+** database). The second argument is a reference to a page that is 
+** currently dirty but has no outstanding references. The page
+** is always associated with the Pager object passed as the first 
+** argument.
+**
+** The job of this function is to make pPg clean by writing its contents
+** out to the database file, if possible. This may involve syncing the
+** journal file. 
+**
+** If successful, sqlite3PcacheMakeClean() is called on the page and
+** SQLITE_OK returned. If an IO error occurs while trying to make the
+** page clean, the IO error code is returned. If the page cannot be
+** made clean for some other reason, but no error occurs, then SQLITE_OK
+** is returned by sqlite3PcacheMakeClean() is not called.
+*/
+static int pagerStress(void *p, PgHdr *pPg){
+  Pager *pPager = (Pager *)p;
+  int rc = SQLITE_OK;
 
-  /* If the read-uncommitted flag is set and a read-lock is requested,
-  ** return early without adding an entry to the BtShared.pLock list. See
-  ** comment in function queryTableLock() for more info on handling 
-  ** the ReadUncommitted flag.
+  assert( pPg->pPager==pPager );
+  assert( pPg->flags&PGHDR_DIRTY );
+
+  /* The doNotSync flag is set by the sqlite3PagerWrite() function while it
+  ** is journalling a set of two or more database pages that are stored
+  ** on the same disk sector. Syncing the journal is not allowed while
+  ** this is happening as it is important that all members of such a
+  ** set of pages are synced to disk together. So, if the page this function
+  ** is trying to make clean will require a journal sync and the doNotSync
+  ** flag is set, return without doing anything. The pcache layer will
+  ** just have to go ahead and allocate a new page buffer instead of
+  ** reusing pPg.
+  **
+  ** Similarly, if the pager has already entered the error state, do not
+  ** try to write the contents of pPg to disk.
   */
-  if( 
-    (p->db) && 
-    (p->db->flags&SQLITE_ReadUncommitted) && 
-    (eLock==READ_LOCK) &&
-    iTable!=MASTER_ROOT
+  if( NEVER(pPager->errCode)
+   || (pPager->doNotSync && pPg->flags&PGHDR_NEED_SYNC)
   ){
     return SQLITE_OK;
   }
 
-  /* First search the list for an existing lock on this table. */
-  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
-    if( pIter->iTable==iTable && pIter->pBtree==p ){
-      pLock = pIter;
-      break;
+  /* Sync the journal file if required. */
+  if( pPg->flags&PGHDR_NEED_SYNC ){
+    rc = syncJournal(pPager);
+    if( rc==SQLITE_OK && pPager->fullSync && 
+      !(pPager->journalMode==PAGER_JOURNALMODE_MEMORY) &&
+      !(sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND)
+    ){
+      pPager->nRec = 0;
+      rc = writeJournalHdr(pPager);
     }
   }
 
-  /* If the above search did not find a BtLock struct associating Btree p
-  ** with table iTable, allocate one and link it into the list.
+  /* If the page number of this page is larger than the current size of
+  ** the database image, it may need to be written to the sub-journal.
+  ** This is because the call to pager_write_pagelist() below will not
+  ** actually write data to the file in this case.
+  **
+  ** Consider the following sequence of events:
+  **
+  **   BEGIN;
+  **     <journal page X>
+  **     <modify page X>
+  **     SAVEPOINT sp;
+  **       <shrink database file to Y pages>
+  **       pagerStress(page X)
+  **     ROLLBACK TO sp;
+  **
+  ** If (X>Y), then when pagerStress is called page X will not be written
+  ** out to the database file, but will be dropped from the cache. Then,
+  ** following the "ROLLBACK TO sp" statement, reading page X will read
+  ** data from the database file. This will be the copy of page X as it
+  ** was when the transaction started, not as it was when "SAVEPOINT sp"
+  ** was executed.
+  **
+  ** The solution is to write the current data for page X into the 
+  ** sub-journal file now (if it is not already there), so that it will
+  ** be restored to its current value when the "ROLLBACK TO sp" is 
+  ** executed.
   */
-  if( !pLock ){
-    pLock = (BtLock *)sqlite3MallocZero(sizeof(BtLock));
-    if( !pLock ){
-      return SQLITE_NOMEM;
-    }
-    pLock->iTable = iTable;
-    pLock->pBtree = p;
-    pLock->pNext = pBt->pLock;
-    pBt->pLock = pLock;
+  if( NEVER(
+      rc==SQLITE_OK && pPg->pgno>pPager->dbSize && subjRequiresPage(pPg)
+  ) ){
+    rc = subjournalPage(pPg);
   }
 
-  /* Set the BtLock.eLock variable to the maximum of the current lock
-  ** and the requested lock. This means if a write-lock was already held
-  ** and a read-lock requested, we don't incorrectly downgrade the lock.
-  */
-  assert( WRITE_LOCK>READ_LOCK );
-  if( eLock>pLock->eLock ){
-    pLock->eLock = eLock;
+  /* Write the contents of the page out to the database file. */
+  if( rc==SQLITE_OK ){
+    pPg->pDirty = 0;
+    rc = pager_write_pagelist(pPg);
   }
 
-  return SQLITE_OK;
+  /* Mark the page as clean. */
+  if( rc==SQLITE_OK ){
+    PAGERTRACE(("STRESS %d page %d\n", PAGERID(pPager), pPg->pgno));
+    sqlite3PcacheMakeClean(pPg);
+  }
+
+  return pager_error(pPager, rc);
 }
-#endif /* !SQLITE_OMIT_SHARED_CACHE */
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
+
 /*
-** Release all the table locks (locks obtained via calls to the lockTable()
-** procedure) held by Btree handle p.
+** Allocate and initialize a new Pager object and put a pointer to it
+** in *ppPager. The pager should eventually be freed by passing it
+** to sqlite3PagerClose().
+**
+** The zFilename argument is the path to the database file to open.
+** If zFilename is NULL then a randomly-named temporary file is created
+** and used as the file to be cached. Temporary files are be deleted
+** automatically when they are closed. If zFilename is ":memory:" then 
+** all information is held in cache. It is never written to disk. 
+** This can be used to implement an in-memory database.
+**
+** The nExtra parameter specifies the number of bytes of space allocated
+** along with each page reference. This space is available to the user
+** via the sqlite3PagerGetExtra() API.
+**
+** The flags argument is used to specify properties that affect the
+** operation of the pager. It should be passed some bitwise combination
+** of the PAGER_OMIT_JOURNAL and PAGER_NO_READLOCK flags.
+**
+** The vfsFlags parameter is a bitmask to pass to the flags parameter
+** of the xOpen() method of the supplied VFS when opening files. 
+**
+** If the pager object is allocated and the specified file opened 
+** successfully, SQLITE_OK is returned and *ppPager set to point to
+** the new pager object. If an error occurs, *ppPager is set to NULL
+** and error code returned. This function may return SQLITE_NOMEM
+** (sqlite3Malloc() is used to allocate memory), SQLITE_CANTOPEN or 
+** various SQLITE_IO_XXX errors.
 */
-static void unlockAllTables(Btree *p){
-  BtShared *pBt = p->pBt;
-  BtLock **ppIter = &pBt->pLock;
+SQLITE_PRIVATE int sqlite3PagerOpen(
+  sqlite3_vfs *pVfs,       /* The virtual file system to use */
+  Pager **ppPager,         /* OUT: Return the Pager structure here */
+  const char *zFilename,   /* Name of the database file to open */
+  int nExtra,              /* Extra bytes append to each in-memory page */
+  int flags,               /* flags controlling this file */
+  int vfsFlags,            /* flags passed through to sqlite3_vfs.xOpen() */
+  void (*xReinit)(DbPage*) /* Function to reinitialize pages */
+){
+  u8 *pPtr;
+  Pager *pPager = 0;       /* Pager object to allocate and return */
+  int rc = SQLITE_OK;      /* Return code */
+  int tempFile = 0;        /* True for temp files (incl. in-memory files) */
+  int memDb = 0;           /* True if this is an in-memory file */
+  int readOnly = 0;        /* True if this is a read-only file */
+  int journalFileSize;     /* Bytes to allocate for each journal fd */
+  char *zPathname = 0;     /* Full path to database file */
+  int nPathname = 0;       /* Number of bytes in zPathname */
+  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
+  int noReadlock = (flags & PAGER_NO_READLOCK)!=0;  /* True to omit read-lock */
+  int pcacheSize = sqlite3PcacheSize();       /* Bytes to allocate for PCache */
+  u16 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
+
+  /* Figure out how much space is required for each journal file-handle
+  ** (there are two of them, the main journal and the sub-journal). This
+  ** is the maximum space required for an in-memory journal file handle 
+  ** and a regular journal file-handle. Note that a "regular journal-handle"
+  ** may be a wrapper capable of caching the first portion of the journal
+  ** file in memory to implement the atomic-write optimization (see 
+  ** source file journal.c).
+  */
+  if( sqlite3JournalSize(pVfs)>sqlite3MemJournalSize() ){
+    journalFileSize = ROUND8(sqlite3JournalSize(pVfs));
+  }else{
+    journalFileSize = ROUND8(sqlite3MemJournalSize());
+  }
 
-  assert( sqlite3BtreeHoldsMutex(p) );
-  assert( p->sharable || 0==*ppIter );
+  /* Set the output variable to NULL in case an error occurs. */
+  *ppPager = 0;
 
-  while( *ppIter ){
-    BtLock *pLock = *ppIter;
-    assert( pBt->pExclusive==0 || pBt->pExclusive==pLock->pBtree );
-    if( pLock->pBtree==p ){
-      *ppIter = pLock->pNext;
-      sqlite3_free(pLock);
-    }else{
-      ppIter = &pLock->pNext;
+  /* Compute and store the full pathname in an allocated buffer pointed
+  ** to by zPathname, length nPathname. Or, if this is a temporary file,
+  ** leave both nPathname and zPathname set to 0.
+  */
+  if( zFilename && zFilename[0] ){
+    nPathname = pVfs->mxPathname+1;
+    zPathname = sqlite3Malloc(nPathname*2);
+    if( zPathname==0 ){
+      return SQLITE_NOMEM;
+    }
+#ifndef SQLITE_OMIT_MEMORYDB
+    if( strcmp(zFilename,":memory:")==0 ){
+      memDb = 1;
+      zPathname[0] = 0;
+    }else
+#endif
+    {
+      zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
+      rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
+    }
+
+    nPathname = sqlite3Strlen30(zPathname);
+    if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
+      /* This branch is taken when the journal path required by
+      ** the database being opened will be more than pVfs->mxPathname
+      ** bytes in length. This means the database cannot be opened,
+      ** as it will not be possible to open the journal file or even
+      ** check for a hot-journal before reading.
+      */
+      rc = SQLITE_CANTOPEN;
+    }
+    if( rc!=SQLITE_OK ){
+      sqlite3_free(zPathname);
+      return rc;
     }
   }
 
-  if( pBt->pExclusive==p ){
-    pBt->pExclusive = 0;
+  /* Allocate memory for the Pager structure, PCache object, the
+  ** three file descriptors, the database file name and the journal 
+  ** file name. The layout in memory is as follows:
+  **
+  **     Pager object                    (sizeof(Pager) bytes)
+  **     PCache object                   (sqlite3PcacheSize() bytes)
+  **     Database file handle            (pVfs->szOsFile bytes)
+  **     Sub-journal file handle         (journalFileSize bytes)
+  **     Main journal file handle        (journalFileSize bytes)
+  **     Database file name              (nPathname+1 bytes)
+  **     Journal file name               (nPathname+8+1 bytes)
+  */
+  pPtr = (u8 *)sqlite3MallocZero(
+    ROUND8(sizeof(*pPager)) +      /* Pager structure */
+    ROUND8(pcacheSize) +           /* PCache object */
+    ROUND8(pVfs->szOsFile) +       /* The main db file */
+    journalFileSize * 2 +          /* The two journal files */ 
+    nPathname + 1 +                /* zFilename */
+    nPathname + 8 + 1              /* zJournal */
+  );
+  assert( EIGHT_BYTE_ALIGNMENT(SQLITE_INT_TO_PTR(journalFileSize)) );
+  if( !pPtr ){
+    sqlite3_free(zPathname);
+    return SQLITE_NOMEM;
   }
-}
-#endif /* SQLITE_OMIT_SHARED_CACHE */
+  pPager =              (Pager*)(pPtr);
+  pPager->pPCache =    (PCache*)(pPtr += ROUND8(sizeof(*pPager)));
+  pPager->fd =   (sqlite3_file*)(pPtr += ROUND8(pcacheSize));
+  pPager->sjfd = (sqlite3_file*)(pPtr += ROUND8(pVfs->szOsFile));
+  pPager->jfd =  (sqlite3_file*)(pPtr += journalFileSize);
+  pPager->zFilename =    (char*)(pPtr += journalFileSize);
+  assert( EIGHT_BYTE_ALIGNMENT(pPager->jfd) );
+
+  /* Fill in the Pager.zFilename and Pager.zJournal buffers, if required. */
+  if( zPathname ){
+    pPager->zJournal =   (char*)(pPtr += nPathname + 1);
+    memcpy(pPager->zFilename, zPathname, nPathname);
+    memcpy(pPager->zJournal, zPathname, nPathname);
+    memcpy(&pPager->zJournal[nPathname], "-journal", 8);
+    if( pPager->zFilename[0]==0 ) pPager->zJournal[0] = 0;
+    sqlite3_free(zPathname);
+  }
+  pPager->pVfs = pVfs;
+  pPager->vfsFlags = vfsFlags;
 
-static void releasePage(MemPage *pPage);  /* Forward reference */
+  /* Open the pager file.
+  */
+  if( zFilename && zFilename[0] && !memDb ){
+    int fout = 0;                    /* VFS flags returned by xOpen() */
+    rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
+    readOnly = (fout&SQLITE_OPEN_READONLY);
 
-/*
-** Verify that the cursor holds a mutex on the BtShared
-*/
-#ifndef NDEBUG
-static int cursorHoldsMutex(BtCursor *p){
-  return sqlite3_mutex_held(p->pBt->mutex);
-}
+    /* If the file was successfully opened for read/write access,
+    ** choose a default page size in case we have to create the
+    ** database file. The default page size is the maximum of:
+    **
+    **    + SQLITE_DEFAULT_PAGE_SIZE,
+    **    + The value returned by sqlite3OsSectorSize()
+    **    + The largest page size that can be written atomically.
+    */
+    if( rc==SQLITE_OK && !readOnly ){
+      setSectorSize(pPager);
+      assert(SQLITE_DEFAULT_PAGE_SIZE<=SQLITE_MAX_DEFAULT_PAGE_SIZE);
+      if( szPageDflt<pPager->sectorSize ){
+        if( pPager->sectorSize>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
+          szPageDflt = SQLITE_MAX_DEFAULT_PAGE_SIZE;
+        }else{
+          szPageDflt = (u16)pPager->sectorSize;
+        }
+      }
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+      {
+        int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+        int ii;
+        assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+        assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+        assert(SQLITE_MAX_DEFAULT_PAGE_SIZE<=65536);
+        for(ii=szPageDflt; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
+          if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ){
+            szPageDflt = ii;
+          }
+        }
+      }
 #endif
+    }
+  }else{
+    /* If a temporary file is requested, it is not opened immediately.
+    ** In this case we accept the default page size and delay actually
+    ** opening the file until the first call to OsWrite().
+    **
+    ** This branch is also run for an in-memory database. An in-memory
+    ** database is the same as a temp-file that is never written out to
+    ** disk and uses an in-memory rollback journal.
+    */ 
+    tempFile = 1;
+    pPager->state = PAGER_EXCLUSIVE;
+    readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
+  }
 
+  /* The following call to PagerSetPagesize() serves to set the value of 
+  ** Pager.pageSize and to allocate the Pager.pTmpSpace buffer.
+  */
+  if( rc==SQLITE_OK ){
+    assert( pPager->memDb==0 );
+    rc = sqlite3PagerSetPagesize(pPager, &szPageDflt, -1);
+    testcase( rc!=SQLITE_OK );
+  }
 
-#ifndef SQLITE_OMIT_INCRBLOB
-/*
-** Invalidate the overflow page-list cache for cursor pCur, if any.
-*/
-static void invalidateOverflowCache(BtCursor *pCur){
-  assert( cursorHoldsMutex(pCur) );
-  sqlite3_free(pCur->aOverflow);
-  pCur->aOverflow = 0;
-}
+  /* If an error occurred in either of the blocks above, free the 
+  ** Pager structure and close the file.
+  */
+  if( rc!=SQLITE_OK ){
+    assert( !pPager->pTmpSpace );
+    sqlite3OsClose(pPager->fd);
+    sqlite3_free(pPager);
+    return rc;
+  }
 
-/*
-** Invalidate the overflow page-list cache for all cursors opened
-** on the shared btree structure pBt.
-*/
-static void invalidateAllOverflowCache(BtShared *pBt){
-  BtCursor *p;
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  for(p=pBt->pCursor; p; p=p->pNext){
-    invalidateOverflowCache(p);
+  /* Initialize the PCache object. */
+  assert( nExtra<1000 );
+  nExtra = ROUND8(nExtra);
+  sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
+                    !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
+
+  PAGERTRACE(("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename));
+  IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))
+
+  pPager->useJournal = (u8)useJournal;
+  pPager->noReadlock = (noReadlock && readOnly) ?1:0;
+  /* pPager->stmtOpen = 0; */
+  /* pPager->stmtInUse = 0; */
+  /* pPager->nRef = 0; */
+  pPager->dbSizeValid = (u8)memDb;
+  /* pPager->stmtSize = 0; */
+  /* pPager->stmtJSize = 0; */
+  /* pPager->nPage = 0; */
+  pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
+  /* pPager->state = PAGER_UNLOCK; */
+  assert( pPager->state == (tempFile ? PAGER_EXCLUSIVE : PAGER_UNLOCK) );
+  /* pPager->errMask = 0; */
+  pPager->tempFile = (u8)tempFile;
+  assert( tempFile==PAGER_LOCKINGMODE_NORMAL 
+          || tempFile==PAGER_LOCKINGMODE_EXCLUSIVE );
+  assert( PAGER_LOCKINGMODE_EXCLUSIVE==1 );
+  pPager->exclusiveMode = (u8)tempFile; 
+  pPager->changeCountDone = pPager->tempFile;
+  pPager->memDb = (u8)memDb;
+  pPager->readOnly = (u8)readOnly;
+  /* pPager->needSync = 0; */
+  assert( useJournal || pPager->tempFile );
+  pPager->noSync = pPager->tempFile;
+  pPager->fullSync = pPager->noSync ?0:1;
+  pPager->sync_flags = SQLITE_SYNC_NORMAL;
+  /* pPager->pFirst = 0; */
+  /* pPager->pFirstSynced = 0; */
+  /* pPager->pLast = 0; */
+  pPager->nExtra = (u16)nExtra;
+  pPager->journalSizeLimit = SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT;
+  assert( isOpen(pPager->fd) || tempFile );
+  setSectorSize(pPager);
+  if( !useJournal ){
+    pPager->journalMode = PAGER_JOURNALMODE_OFF;
+  }else if( memDb ){
+    pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
   }
+  /* pPager->xBusyHandler = 0; */
+  /* pPager->pBusyHandlerArg = 0; */
+  pPager->xReiniter = xReinit;
+  /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
+  *ppPager = pPager;
+  return SQLITE_OK;
 }
-#else
-  #define invalidateOverflowCache(x)
-  #define invalidateAllOverflowCache(x)
-#endif
 
-/*
-** Save the current cursor position in the variables BtCursor.nKey 
-** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK.
-*/
-static int saveCursorPosition(BtCursor *pCur){
-  int rc;
 
-  assert( CURSOR_VALID==pCur->eState );
-  assert( 0==pCur->pKey );
-  assert( cursorHoldsMutex(pCur) );
 
-  rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
+/*
+** This function is called after transitioning from PAGER_UNLOCK to
+** PAGER_SHARED state. It tests if there is a hot journal present in
+** the file-system for the given pager. A hot journal is one that 
+** needs to be played back. According to this function, a hot-journal
+** file exists if the following criteria are met:
+**
+**   * The journal file exists in the file system, and
+**   * No process holds a RESERVED or greater lock on the database file, and
+**   * The database file itself is greater than 0 bytes in size, and
+**   * The first byte of the journal file exists and is not 0x00.
+**
+** If the current size of the database file is 0 but a journal file
+** exists, that is probably an old journal left over from a prior
+** database with the same name. In this case the journal file is
+** just deleted using OsDelete, *pExists is set to 0 and SQLITE_OK
+** is returned.
+**
+** This routine does not check if there is a master journal filename
+** at the end of the file. If there is, and that master journal file
+** does not exist, then the journal file is not really hot. In this
+** case this routine will return a false-positive. The pager_playback()
+** routine will discover that the journal file is not really hot and 
+** will not roll it back. 
+**
+** If a hot-journal file is found to exist, *pExists is set to 1 and 
+** SQLITE_OK returned. If no hot-journal file is present, *pExists is
+** set to 0 and SQLITE_OK returned. If an IO error occurs while trying
+** to determine whether or not a hot-journal file exists, the IO error
+** code is returned and the value of *pExists is undefined.
+*/
+static int hasHotJournal(Pager *pPager, int *pExists){
+  sqlite3_vfs * const pVfs = pPager->pVfs;
+  int rc;                       /* Return code */
+  int exists;                   /* True if a journal file is present */
 
-  /* If this is an intKey table, then the above call to BtreeKeySize()
-  ** stores the integer key in pCur->nKey. In this case this value is
-  ** all that is required. Otherwise, if pCur is not open on an intKey
-  ** table, then malloc space for and store the pCur->nKey bytes of key 
-  ** data.
-  */
-  if( rc==SQLITE_OK && 0==pCur->pPage->intKey){
-    void *pKey = sqlite3_malloc(pCur->nKey);
-    if( pKey ){
-      rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
+  assert( pPager!=0 );
+  assert( pPager->useJournal );
+  assert( isOpen(pPager->fd) );
+  assert( !isOpen(pPager->jfd) );
+  assert( pPager->state <= PAGER_SHARED );
+
+  *pExists = 0;
+  rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &exists);
+  if( rc==SQLITE_OK && exists ){
+    int locked;                 /* True if some process holds a RESERVED lock */
+
+    /* Race condition here:  Another process might have been holding the
+    ** the RESERVED lock and have a journal open at the sqlite3OsAccess() 
+    ** call above, but then delete the journal and drop the lock before
+    ** we get to the following sqlite3OsCheckReservedLock() call.  If that
+    ** is the case, this routine might think there is a hot journal when
+    ** in fact there is none.  This results in a false-positive which will
+    ** be dealt with by the playback routine.  Ticket #3883.
+    */
+    rc = sqlite3OsCheckReservedLock(pPager->fd, &locked);
+    if( rc==SQLITE_OK && !locked ){
+      int nPage;
+
+      /* Check the size of the database file. If it consists of 0 pages,
+      ** then delete the journal file. See the header comment above for 
+      ** the reasoning here.  Delete the obsolete journal file under
+      ** a RESERVED lock to avoid race conditions and to avoid violating
+      ** [H33020].
+      */
+      rc = sqlite3PagerPagecount(pPager, &nPage);
       if( rc==SQLITE_OK ){
-        pCur->pKey = pKey;
-      }else{
-        sqlite3_free(pKey);
+        if( nPage==0 ){
+          sqlite3BeginBenignMalloc();
+          if( sqlite3OsLock(pPager->fd, RESERVED_LOCK)==SQLITE_OK ){
+            sqlite3OsDelete(pVfs, pPager->zJournal, 0);
+            sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
+          }
+          sqlite3EndBenignMalloc();
+        }else{
+          /* The journal file exists and no other connection has a reserved
+          ** or greater lock on the database file. Now check that there is
+          ** at least one non-zero bytes at the start of the journal file.
+          ** If there is, then we consider this journal to be hot. If not, 
+          ** it can be ignored.
+          */
+          int f = SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL;
+          rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &f);
+          if( rc==SQLITE_OK ){
+            u8 first = 0;
+            rc = sqlite3OsRead(pPager->jfd, (void *)&first, 1, 0);
+            if( rc==SQLITE_IOERR_SHORT_READ ){
+              rc = SQLITE_OK;
+            }
+            sqlite3OsClose(pPager->jfd);
+            *pExists = (first!=0);
+          }else if( rc==SQLITE_CANTOPEN ){
+            /* If we cannot open the rollback journal file in order to see if
+            ** its has a zero header, that might be due to an I/O error, or
+            ** it might be due to the race condition described above and in
+            ** ticket #3883.  Either way, assume that the journal is hot.
+            ** This might be a false positive.  But if it is, then the
+            ** automatic journal playback and recovery mechanism will deal
+            ** with it under an EXCLUSIVE lock where we do not need to
+            ** worry so much with race conditions.
+            */
+            *pExists = 1;
+            rc = SQLITE_OK;
+          }
+        }
       }
-    }else{
-      rc = SQLITE_NOMEM;
     }
   }
-  assert( !pCur->pPage->intKey || !pCur->pKey );
-
-  if( rc==SQLITE_OK ){
-    releasePage(pCur->pPage);
-    pCur->pPage = 0;
-    pCur->eState = CURSOR_REQUIRESEEK;
-  }
 
-  invalidateOverflowCache(pCur);
   return rc;
 }
 
 /*
-** Save the positions of all cursors except pExcept open on the table 
-** with root-page iRoot. Usually, this is called just before cursor
-** pExcept is used to modify the table (BtreeDelete() or BtreeInsert()).
+** Read the content for page pPg out of the database file and into 
+** pPg->pData. A shared lock or greater must be held on the database
+** file before this function is called.
+**
+** If page 1 is read, then the value of Pager.dbFileVers[] is set to
+** the value read from the database file.
+**
+** If an IO error occurs, then the IO error is returned to the caller.
+** Otherwise, SQLITE_OK is returned.
 */
-static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
-  BtCursor *p;
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( pExcept==0 || pExcept->pBt==pBt );
-  for(p=pBt->pCursor; p; p=p->pNext){
-    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) && 
-        p->eState==CURSOR_VALID ){
-      int rc = saveCursorPosition(p);
-      if( SQLITE_OK!=rc ){
-        return rc;
-      }
-    }
+static int readDbPage(PgHdr *pPg){
+  Pager *pPager = pPg->pPager; /* Pager object associated with page pPg */
+  Pgno pgno = pPg->pgno;       /* Page number to read */
+  int rc;                      /* Return code */
+  i64 iOffset;                 /* Byte offset of file to read from */
+
+  assert( pPager->state>=PAGER_SHARED && !MEMDB );
+  assert( isOpen(pPager->fd) );
+
+  if( NEVER(!isOpen(pPager->fd)) ){
+    assert( pPager->tempFile );
+    memset(pPg->pData, 0, pPager->pageSize);
+    return SQLITE_OK;
   }
-  return SQLITE_OK;
-}
+  iOffset = (pgno-1)*(i64)pPager->pageSize;
+  rc = sqlite3OsRead(pPager->fd, pPg->pData, pPager->pageSize, iOffset);
+  if( rc==SQLITE_IOERR_SHORT_READ ){
+    rc = SQLITE_OK;
+  }
+  if( pgno==1 ){
+    u8 *dbFileVers = &((u8*)pPg->pData)[24];
+    memcpy(&pPager->dbFileVers, dbFileVers, sizeof(pPager->dbFileVers));
+  }
+  CODEC1(pPager, pPg->pData, pgno, 3, rc = SQLITE_NOMEM);
 
-/*
-** Clear the current cursor position.
-*/
-static void clearCursorPosition(BtCursor *pCur){
-  assert( cursorHoldsMutex(pCur) );
-  sqlite3_free(pCur->pKey);
-  pCur->pKey = 0;
-  pCur->eState = CURSOR_INVALID;
+  PAGER_INCR(sqlite3_pager_readdb_count);
+  PAGER_INCR(pPager->nRead);
+  IOTRACE(("PGIN %p %d\n", pPager, pgno));
+  PAGERTRACE(("FETCH %d page %d hash(%08x)\n",
+               PAGERID(pPager), pgno, pager_pagehash(pPg)));
+
+  return rc;
 }
 
 /*
-** Restore the cursor to the position it was in (or as close to as possible)
-** when saveCursorPosition() was called. Note that this call deletes the 
-** saved position info stored by saveCursorPosition(), so there can be
-** at most one effective restoreOrClearCursorPosition() call after each 
-** saveCursorPosition().
+** This function is called to obtain a shared lock on the database file.
+** It is illegal to call sqlite3PagerAcquire() until after this function
+** has been successfully called. If a shared-lock is already held when
+** this function is called, it is a no-op.
+**
+** The following operations are also performed by this function.
+**
+**   1) If the pager is currently in PAGER_UNLOCK state (no lock held
+**      on the database file), then an attempt is made to obtain a
+**      SHARED lock on the database file. Immediately after obtaining
+**      the SHARED lock, the file-system is checked for a hot-journal,
+**      which is played back if present. Following any hot-journal 
+**      rollback, the contents of the cache are validated by checking
+**      the 'change-counter' field of the database file header and
+**      discarded if they are found to be invalid.
+**
+**   2) If the pager is running in exclusive-mode, and there are currently
+**      no outstanding references to any pages, and is in the error state,
+**      then an attempt is made to clear the error state by discarding
+**      the contents of the page cache and rolling back any open journal
+**      file.
+**
+** If the operation described by (2) above is not attempted, and if the
+** pager is in an error state other than SQLITE_FULL when this is called,
+** the error state error code is returned. It is permitted to read the
+** database when in SQLITE_FULL error state.
 **
-** If the second argument argument - doSeek - is false, then instead of 
-** returning the cursor to its saved position, any saved position is deleted
-** and the cursor state set to CURSOR_INVALID.
+** Otherwise, if everything is successful, SQLITE_OK is returned. If an
+** IO error occurs while locking the database, checking for a hot-journal
+** file or rolling back a journal file, the IO error code is returned.
 */
-SQLITE_PRIVATE int sqlite3BtreeRestoreOrClearCursorPosition(BtCursor *pCur){
-  int rc;
-  assert( cursorHoldsMutex(pCur) );
-  assert( pCur->eState>=CURSOR_REQUIRESEEK );
-  if( pCur->eState==CURSOR_FAULT ){
-    return pCur->skip;
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
+  int rc = SQLITE_OK;                /* Return code */
+  int isErrorReset = 0;              /* True if recovering from error state */
+
+  /* This routine is only called from b-tree and only when there are no
+  ** outstanding pages */
+  assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+  if( NEVER(MEMDB && pPager->errCode) ){ return pPager->errCode; }
+
+  /* If this database is in an error-state, now is a chance to clear
+  ** the error. Discard the contents of the pager-cache and rollback
+  ** any hot journal in the file-system.
+  */
+  if( pPager->errCode ){
+    if( isOpen(pPager->jfd) || pPager->zJournal ){
+      isErrorReset = 1;
+    }
+    pPager->errCode = SQLITE_OK;
+    pager_reset(pPager);
   }
-#ifndef SQLITE_OMIT_INCRBLOB
-  if( pCur->isIncrblobHandle ){
-    return SQLITE_ABORT;
+
+  if( pPager->state==PAGER_UNLOCK || isErrorReset ){
+    sqlite3_vfs * const pVfs = pPager->pVfs;
+    int isHotJournal = 0;
+    assert( !MEMDB );
+    assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+    if( pPager->noReadlock ){
+      assert( pPager->readOnly );
+      pPager->state = PAGER_SHARED;
+    }else{
+      rc = pager_wait_on_lock(pPager, SHARED_LOCK);
+      if( rc!=SQLITE_OK ){
+        assert( pPager->state==PAGER_UNLOCK );
+        return pager_error(pPager, rc);
+      }
+    }
+    assert( pPager->state>=SHARED_LOCK );
+
+    /* If a journal file exists, and there is no RESERVED lock on the
+    ** database file, then it either needs to be played back or deleted.
+    */
+    if( !isErrorReset ){
+      assert( pPager->state <= PAGER_SHARED );
+      rc = hasHotJournal(pPager, &isHotJournal);
+      if( rc!=SQLITE_OK ){
+        goto failed;
+      }
+    }
+    if( isErrorReset || isHotJournal ){
+      /* Get an EXCLUSIVE lock on the database file. At this point it is
+      ** important that a RESERVED lock is not obtained on the way to the
+      ** EXCLUSIVE lock. If it were, another process might open the
+      ** database file, detect the RESERVED lock, and conclude that the
+      ** database is safe to read while this process is still rolling the 
+      ** hot-journal back.
+      ** 
+      ** Because the intermediate RESERVED lock is not requested, any
+      ** other process attempting to access the database file will get to 
+      ** this point in the code and fail to obtain its own EXCLUSIVE lock 
+      ** on the database file.
+      */
+      if( pPager->state<EXCLUSIVE_LOCK ){
+        rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
+        if( rc!=SQLITE_OK ){
+          rc = pager_error(pPager, rc);
+          goto failed;
+        }
+        pPager->state = PAGER_EXCLUSIVE;
+      }
+ 
+      /* Open the journal for read/write access. This is because in 
+      ** exclusive-access mode the file descriptor will be kept open and
+      ** possibly used for a transaction later on. On some systems, the
+      ** OsTruncate() call used in exclusive-access mode also requires
+      ** a read/write file handle.
+      */
+      if( !isOpen(pPager->jfd) ){
+        int res;
+        rc = sqlite3OsAccess(pVfs,pPager->zJournal,SQLITE_ACCESS_EXISTS,&res);
+        if( rc==SQLITE_OK ){
+          if( res ){
+            int fout = 0;
+            int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
+            assert( !pPager->tempFile );
+            rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
+            assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+            if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
+              rc = SQLITE_CANTOPEN;
+              sqlite3OsClose(pPager->jfd);
+            }
+          }else{
+            /* If the journal does not exist, it usually means that some 
+            ** other connection managed to get in and roll it back before 
+            ** this connection obtained the exclusive lock above. Or, it 
+            ** may mean that the pager was in the error-state when this
+            ** function was called and the journal file does not exist.  */
+            rc = pager_end_transaction(pPager, 0);
+          }
+        }
+      }
+      if( rc!=SQLITE_OK ){
+        goto failed;
+      }
+
+      /* TODO: Why are these cleared here? Is it necessary? */
+      pPager->journalStarted = 0;
+      pPager->journalOff = 0;
+      pPager->setMaster = 0;
+      pPager->journalHdr = 0;
+ 
+      /* Playback and delete the journal.  Drop the database write
+      ** lock and reacquire the read lock. Purge the cache before
+      ** playing back the hot-journal so that we don't end up with
+      ** an inconsistent cache.
+      */
+      if( isOpen(pPager->jfd) ){
+        rc = pager_playback(pPager, 1);
+        if( rc!=SQLITE_OK ){
+          rc = pager_error(pPager, rc);
+          goto failed;
+        }
+      }
+      assert( (pPager->state==PAGER_SHARED)
+           || (pPager->exclusiveMode && pPager->state>PAGER_SHARED)
+      );
+    }
+
+    if( pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0 ){
+      /* The shared-lock has just been acquired on the database file
+      ** and there are already pages in the cache (from a previous
+      ** read or write transaction).  Check to see if the database
+      ** has been modified.  If the database has changed, flush the
+      ** cache.
+      **
+      ** Database changes is detected by looking at 15 bytes beginning
+      ** at offset 24 into the file.  The first 4 of these 16 bytes are
+      ** a 32-bit counter that is incremented with each change.  The
+      ** other bytes change randomly with each file change when
+      ** a codec is in use.
+      ** 
+      ** There is a vanishingly small chance that a change will not be 
+      ** detected.  The chance of an undetected change is so small that
+      ** it can be neglected.
+      */
+      char dbFileVers[sizeof(pPager->dbFileVers)];
+      sqlite3PagerPagecount(pPager, 0);
+
+      if( pPager->errCode ){
+        rc = pPager->errCode;
+        goto failed;
+      }
+
+      assert( pPager->dbSizeValid );
+      if( pPager->dbSize>0 ){
+        IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
+        rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers), 24);
+        if( rc!=SQLITE_OK ){
+          goto failed;
+        }
+      }else{
+        memset(dbFileVers, 0, sizeof(dbFileVers));
+      }
+
+      if( memcmp(pPager->dbFileVers, dbFileVers, sizeof(dbFileVers))!=0 ){
+        pager_reset(pPager);
+      }
+    }
+    assert( pPager->exclusiveMode || pPager->state==PAGER_SHARED );
   }
-#endif
-  pCur->eState = CURSOR_INVALID;
-  rc = sqlite3BtreeMoveto(pCur, pCur->pKey, 0, pCur->nKey, 0, &pCur->skip);
-  if( rc==SQLITE_OK ){
-    sqlite3_free(pCur->pKey);
-    pCur->pKey = 0;
-    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
+
+ failed:
+  if( rc!=SQLITE_OK ){
+    /* pager_unlock() is a no-op for exclusive mode and in-memory databases. */
+    pager_unlock(pPager);
   }
   return rc;
 }
 
-#define restoreOrClearCursorPosition(p) \
-  (p->eState>=CURSOR_REQUIRESEEK ? \
-         sqlite3BtreeRestoreOrClearCursorPosition(p) : \
-         SQLITE_OK)
-
-#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Given a page number of a regular database page, return the page
-** number for the pointer-map page that contains the entry for the
-** input page number.
-*/
-static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
-  int nPagesPerMapPage, iPtrMap, ret;
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  nPagesPerMapPage = (pBt->usableSize/5)+1;
-  iPtrMap = (pgno-2)/nPagesPerMapPage;
-  ret = (iPtrMap*nPagesPerMapPage) + 2; 
-  if( ret==PENDING_BYTE_PAGE(pBt) ){
-    ret++;
+** If the reference count has reached zero, rollback any active
+** transaction and unlock the pager.
+**
+** Except, in locking_mode=EXCLUSIVE when there is nothing to in
+** the rollback journal, the unlock is not performed and there is
+** nothing to rollback, so this routine is a no-op.
+*/ 
+static void pagerUnlockIfUnused(Pager *pPager){
+  if( (sqlite3PcacheRefCount(pPager->pPCache)==0)
+   && (!pPager->exclusiveMode || pPager->journalOff>0) 
+  ){
+    pagerUnlockAndRollback(pPager);
   }
-  return ret;
 }
 
 /*
-** Write an entry into the pointer map.
+** Acquire a reference to page number pgno in pager pPager (a page
+** reference has type DbPage*). If the requested reference is 
+** successfully obtained, it is copied to *ppPage and SQLITE_OK returned.
 **
-** This routine updates the pointer map entry for page number 'key'
-** so that it maps to type 'eType' and parent page number 'pgno'.
-** An error code is returned if something goes wrong, otherwise SQLITE_OK.
+** If the requested page is already in the cache, it is returned. 
+** Otherwise, a new page object is allocated and populated with data
+** read from the database file. In some cases, the pcache module may
+** choose not to allocate a new page object and may reuse an existing
+** object with no outstanding references.
+**
+** The extra data appended to a page is always initialized to zeros the 
+** first time a page is loaded into memory. If the page requested is 
+** already in the cache when this function is called, then the extra
+** data is left as it was when the page object was last used.
+**
+** If the database image is smaller than the requested page or if a 
+** non-zero value is passed as the noContent parameter and the 
+** requested page is not already stored in the cache, then no 
+** actual disk read occurs. In this case the memory image of the 
+** page is initialized to all zeros. 
+**
+** If noContent is true, it means that we do not care about the contents
+** of the page. This occurs in two seperate scenarios:
+**
+**   a) When reading a free-list leaf page from the database, and
+**
+**   b) When a savepoint is being rolled back and we need to load
+**      a new page into the cache to populate with the data read
+**      from the savepoint journal.
+**
+** If noContent is true, then the data returned is zeroed instead of
+** being read from the database. Additionally, the bits corresponding
+** to pgno in Pager.pInJournal (bitvec of pages already written to the
+** journal file) and the PagerSavepoint.pInSavepoint bitvecs of any open
+** savepoints are set. This means if the page is made writable at any
+** point in the future, using a call to sqlite3PagerWrite(), its contents
+** will not be journaled. This saves IO.
+**
+** The acquisition might fail for several reasons.  In all cases,
+** an appropriate error code is returned and *ppPage is set to NULL.
+**
+** See also sqlite3PagerLookup().  Both this routine and Lookup() attempt
+** to find a page in the in-memory cache first.  If the page is not already
+** in memory, this routine goes to disk to read it in whereas Lookup()
+** just returns 0.  This routine acquires a read-lock the first time it
+** has to go to disk, and could also playback an old journal if necessary.
+** Since Lookup() never goes to disk, it never has to deal with locks
+** or journal files.
 */
-static int ptrmapPut(BtShared *pBt, Pgno key, u8 eType, Pgno parent){
-  DbPage *pDbPage;  /* The pointer map page */
-  u8 *pPtrmap;      /* The pointer map data */
-  Pgno iPtrmap;     /* The pointer map page number */
-  int offset;       /* Offset in pointer map page */
+SQLITE_PRIVATE int sqlite3PagerAcquire(
+  Pager *pPager,      /* The pager open on the database file */
+  Pgno pgno,          /* Page number to fetch */
+  DbPage **ppPage,    /* Write a pointer to the page here */
+  int noContent       /* Do not bother reading content from disk if true */
+){
   int rc;
+  PgHdr *pPg;
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  /* The master-journal page number must never be used as a pointer map page */
-  assert( 0==PTRMAP_ISPAGE(pBt, PENDING_BYTE_PAGE(pBt)) );
+  assert( assert_pager_state(pPager) );
+  assert( pPager->state>PAGER_UNLOCK );
 
-  assert( pBt->autoVacuum );
-  if( key==0 ){
+  if( pgno==0 ){
     return SQLITE_CORRUPT_BKPT;
   }
-  iPtrmap = PTRMAP_PAGENO(pBt, key);
-  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  offset = PTRMAP_PTROFFSET(pBt, key);
-  pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
 
-  if( eType!=pPtrmap[offset] || get4byte(&pPtrmap[offset+1])!=parent ){
-    TRACE(("PTRMAP_UPDATE: %d->(%d,%d)\n", key, eType, parent));
-    rc = sqlite3PagerWrite(pDbPage);
-    if( rc==SQLITE_OK ){
-      pPtrmap[offset] = eType;
-      put4byte(&pPtrmap[offset+1], parent);
-    }
+  /* If the pager is in the error state, return an error immediately. 
+  ** Otherwise, request the page from the PCache layer. */
+  if( pPager->errCode!=SQLITE_OK && pPager->errCode!=SQLITE_FULL ){
+    rc = pPager->errCode;
+  }else{
+    rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage);
   }
 
-  sqlite3PagerUnref(pDbPage);
-  return rc;
-}
+  if( rc!=SQLITE_OK ){
+    /* Either the call to sqlite3PcacheFetch() returned an error or the
+    ** pager was already in the error-state when this function was called.
+    ** Set pPg to 0 and jump to the exception handler.  */
+    pPg = 0;
+    goto pager_acquire_err;
+  }
+  assert( (*ppPage)->pgno==pgno );
+  assert( (*ppPage)->pPager==pPager || (*ppPage)->pPager==0 );
+
+  if( (*ppPage)->pPager ){
+    /* In this case the pcache already contains an initialized copy of
+    ** the page. Return without further ado.  */
+    assert( pgno<=PAGER_MAX_PGNO && pgno!=PAGER_MJ_PGNO(pPager) );
+    PAGER_INCR(pPager->nHit);
+    return SQLITE_OK;
 
-/*
-** Read an entry from the pointer map.
-**
-** This routine retrieves the pointer map entry for page 'key', writing
-** the type and parent page number to *pEType and *pPgno respectively.
-** An error code is returned if something goes wrong, otherwise SQLITE_OK.
-*/
-static int ptrmapGet(BtShared *pBt, Pgno key, u8 *pEType, Pgno *pPgno){
-  DbPage *pDbPage;   /* The pointer map page */
-  int iPtrmap;       /* Pointer map page index */
-  u8 *pPtrmap;       /* Pointer map page data */
-  int offset;        /* Offset of entry in pointer map */
-  int rc;
+  }else{
+    /* The pager cache has created a new page. Its content needs to 
+    ** be initialized.  */
+    int nMax;
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
+    PAGER_INCR(pPager->nMiss);
+    pPg = *ppPage;
+    pPg->pPager = pPager;
 
-  iPtrmap = PTRMAP_PAGENO(pBt, key);
-  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
-  if( rc!=0 ){
-    return rc;
-  }
-  pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
+    /* The maximum page number is 2^31. Return SQLITE_CORRUPT if a page
+    ** number greater than this, or the unused locking-page, is requested. */
+    if( pgno>PAGER_MAX_PGNO || pgno==PAGER_MJ_PGNO(pPager) ){
+      rc = SQLITE_CORRUPT_BKPT;
+      goto pager_acquire_err;
+    }
 
-  offset = PTRMAP_PTROFFSET(pBt, key);
-  assert( pEType!=0 );
-  *pEType = pPtrmap[offset];
-  if( pPgno ) *pPgno = get4byte(&pPtrmap[offset+1]);
+    rc = sqlite3PagerPagecount(pPager, &nMax);
+    if( rc!=SQLITE_OK ){
+      goto pager_acquire_err;
+    }
+
+    if( nMax<(int)pgno || MEMDB || noContent ){
+      if( pgno>pPager->mxPgno ){
+	rc = SQLITE_FULL;
+	goto pager_acquire_err;
+      }
+      if( noContent ){
+        /* Failure to set the bits in the InJournal bit-vectors is benign.
+        ** It merely means that we might do some extra work to journal a 
+        ** page that does not need to be journaled.  Nevertheless, be sure 
+        ** to test the case where a malloc error occurs while trying to set 
+        ** a bit in a bit vector.
+        */
+        sqlite3BeginBenignMalloc();
+        if( pgno<=pPager->dbOrigSize ){
+          TESTONLY( rc = ) sqlite3BitvecSet(pPager->pInJournal, pgno);
+          testcase( rc==SQLITE_NOMEM );
+        }
+        TESTONLY( rc = ) addToSavepointBitvecs(pPager, pgno);
+        testcase( rc==SQLITE_NOMEM );
+        sqlite3EndBenignMalloc();
+      }else{
+        memset(pPg->pData, 0, pPager->pageSize);
+      }
+      IOTRACE(("ZERO %p %d\n", pPager, pgno));
+    }else{
+      assert( pPg->pPager==pPager );
+      rc = readDbPage(pPg);
+      if( rc!=SQLITE_OK ){
+        goto pager_acquire_err;
+      }
+    }
+#ifdef SQLITE_CHECK_PAGES
+    pPg->pageHash = pager_pagehash(pPg);
+#endif
+  }
 
-  sqlite3PagerUnref(pDbPage);
-  if( *pEType<1 || *pEType>5 ) return SQLITE_CORRUPT_BKPT;
   return SQLITE_OK;
-}
 
-#endif /* SQLITE_OMIT_AUTOVACUUM */
+pager_acquire_err:
+  assert( rc!=SQLITE_OK );
+  if( pPg ){
+    sqlite3PcacheDrop(pPg);
+  }
+  pagerUnlockIfUnused(pPager);
 
-/*
-** Given a btree page and a cell index (0 means the first cell on
-** the page, 1 means the second cell, and so forth) return a pointer
-** to the cell content.
-**
-** This routine works only for pages that do not contain overflow cells.
-*/
-#define findCell(pPage, iCell) \
-  ((pPage)->aData + get2byte(&(pPage)->aData[(pPage)->cellOffset+2*(iCell)]))
-#ifdef SQLITE_TEST
-SQLITE_PRIVATE u8 *sqlite3BtreeFindCell(MemPage *pPage, int iCell){
-  assert( iCell>=0 );
-  assert( iCell<get2byte(&pPage->aData[pPage->hdrOffset+3]) );
-  return findCell(pPage, iCell);
+  *ppPage = 0;
+  return rc;
 }
-#endif
 
 /*
-** This a more complex version of sqlite3BtreeFindCell() that works for
-** pages that do contain overflow cells.  See insert
+** Acquire a page if it is already in the in-memory cache.  Do
+** not read the page from disk.  Return a pointer to the page,
+** or 0 if the page is not in cache. Also, return 0 if the 
+** pager is in PAGER_UNLOCK state when this function is called,
+** or if the pager is in an error state other than SQLITE_FULL.
+**
+** See also sqlite3PagerGet().  The difference between this routine
+** and sqlite3PagerGet() is that _get() will go to the disk and read
+** in the page if the page is not already in cache.  This routine
+** returns NULL if the page is not in cache or if a disk I/O error 
+** has ever happened.
 */
-static u8 *findOverflowCell(MemPage *pPage, int iCell){
-  int i;
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  for(i=pPage->nOverflow-1; i>=0; i--){
-    int k;
-    struct _OvflCell *pOvfl;
-    pOvfl = &pPage->aOvfl[i];
-    k = pOvfl->idx;
-    if( k<=iCell ){
-      if( k==iCell ){
-        return pOvfl->pCell;
-      }
-      iCell--;
-    }
-  }
-  return findCell(pPage, iCell);
+SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
+  PgHdr *pPg = 0;
+  assert( pPager!=0 );
+  assert( pgno!=0 );
+  assert( pPager->pPCache!=0 );
+  assert( pPager->state > PAGER_UNLOCK );
+  sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
+  return pPg;
 }
 
 /*
-** Parse a cell content block and fill in the CellInfo structure.  There
-** are two versions of this function.  sqlite3BtreeParseCell() takes a 
-** cell index as the second argument and sqlite3BtreeParseCellPtr() 
-** takes a pointer to the body of the cell as its second argument.
+** Release a page reference.
 **
-** Within this file, the parseCell() macro can be called instead of
-** sqlite3BtreeParseCellPtr(). Using some compilers, this will be faster.
+** If the number of references to the page drop to zero, then the
+** page is added to the LRU list.  When all references to all pages
+** are released, a rollback occurs and the lock on the database is
+** removed.
 */
-SQLITE_PRIVATE void sqlite3BtreeParseCellPtr(
-  MemPage *pPage,         /* Page containing the cell */
-  u8 *pCell,              /* Pointer to the cell text. */
-  CellInfo *pInfo         /* Fill in this structure */
-){
-  int n;                  /* Number bytes in cell content header */
-  u32 nPayload;           /* Number of bytes of cell payload */
-
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-
-  pInfo->pCell = pCell;
-  assert( pPage->leaf==0 || pPage->leaf==1 );
-  n = pPage->childPtrSize;
-  assert( n==4-4*pPage->leaf );
-  if( pPage->hasData ){
-    n += getVarint32(&pCell[n], nPayload);
-  }else{
-    nPayload = 0;
-  }
-  pInfo->nData = nPayload;
-  if( pPage->intKey ){
-    n += getVarint(&pCell[n], (u64 *)&pInfo->nKey);
-  }else{
-    u32 x;
-    n += getVarint32(&pCell[n], x);
-    pInfo->nKey = x;
-    nPayload += x;
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage *pPg){
+  if( pPg ){
+    Pager *pPager = pPg->pPager;
+    sqlite3PcacheRelease(pPg);
+    pagerUnlockIfUnused(pPager);
   }
-  pInfo->nPayload = nPayload;
-  pInfo->nHeader = n;
-  if( nPayload<=pPage->maxLocal ){
-    /* This is the (easy) common case where the entire payload fits
-    ** on the local page.  No overflow is required.
-    */
-    int nSize;          /* Total size of cell content in bytes */
-    pInfo->nLocal = nPayload;
-    pInfo->iOverflow = 0;
-    nSize = nPayload + n;
-    if( nSize<4 ){
-      nSize = 4;        /* Minimum cell size is 4 */
-    }
-    pInfo->nSize = nSize;
-  }else{
-    /* If the payload will not fit completely on the local page, we have
-    ** to decide how much to store locally and how much to spill onto
-    ** overflow pages.  The strategy is to minimize the amount of unused
-    ** space on overflow pages while keeping the amount of local storage
-    ** in between minLocal and maxLocal.
-    **
-    ** Warning:  changing the way overflow payload is distributed in any
-    ** way will result in an incompatible file format.
-    */
-    int minLocal;  /* Minimum amount of payload held locally */
-    int maxLocal;  /* Maximum amount of payload held locally */
-    int surplus;   /* Overflow payload available for local storage */
+}
 
-    minLocal = pPage->minLocal;
-    maxLocal = pPage->maxLocal;
-    surplus = minLocal + (nPayload - minLocal)%(pPage->pBt->usableSize - 4);
-    if( surplus <= maxLocal ){
-      pInfo->nLocal = surplus;
+/*
+** If the main journal file has already been opened, ensure that the
+** sub-journal file is open too. If the main journal is not open,
+** this function is a no-op.
+**
+** SQLITE_OK is returned if everything goes according to plan. 
+** An SQLITE_IOERR_XXX error code is returned if a call to 
+** sqlite3OsOpen() fails.
+*/
+static int openSubJournal(Pager *pPager){
+  int rc = SQLITE_OK;
+  if( isOpen(pPager->jfd) && !isOpen(pPager->sjfd) ){
+    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
+      sqlite3MemJournalOpen(pPager->sjfd);
     }else{
-      pInfo->nLocal = minLocal;
+      rc = pagerOpentemp(pPager, pPager->sjfd, SQLITE_OPEN_SUBJOURNAL);
     }
-    pInfo->iOverflow = pInfo->nLocal + n;
-    pInfo->nSize = pInfo->iOverflow + 4;
   }
-}
-#define parseCell(pPage, iCell, pInfo) \
-  sqlite3BtreeParseCellPtr((pPage), findCell((pPage), (iCell)), (pInfo))
-SQLITE_PRIVATE void sqlite3BtreeParseCell(
-  MemPage *pPage,         /* Page containing the cell */
-  int iCell,              /* The cell index.  First cell is 0 */
-  CellInfo *pInfo         /* Fill in this structure */
-){
-  parseCell(pPage, iCell, pInfo);
+  return rc;
 }
 
 /*
-** Compute the total number of bytes that a Cell needs in the cell
-** data area of the btree-page.  The return number includes the cell
-** data header and the local payload, but not any overflow page or
-** the space used by the cell pointer.
+** This function is called at the start of every write transaction.
+** There must already be a RESERVED or EXCLUSIVE lock on the database 
+** file when this routine is called.
+**
+** Open the journal file for pager pPager and write a journal header
+** to the start of it. If there are active savepoints, open the sub-journal
+** as well. This function is only used when the journal file is being 
+** opened to write a rollback log for a transaction. It is not used 
+** when opening a hot journal file to roll it back.
+**
+** If the journal file is already open (as it may be in exclusive mode),
+** then this function just writes a journal header to the start of the
+** already open file. 
+**
+** Whether or not the journal file is opened by this function, the
+** Pager.pInJournal bitvec structure is allocated.
+**
+** Return SQLITE_OK if everything is successful. Otherwise, return 
+** SQLITE_NOMEM if the attempt to allocate Pager.pInJournal fails, or 
+** an IO error code if opening or writing the journal file fails.
 */
-#ifndef NDEBUG
-static u16 cellSize(MemPage *pPage, int iCell){
-  CellInfo info;
-  sqlite3BtreeParseCell(pPage, iCell, &info);
-  return info.nSize;
-}
-#endif
-static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
-  CellInfo info;
-  sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-  return info.nSize;
-}
+static int pager_open_journal(Pager *pPager){
+  int rc = SQLITE_OK;                        /* Return code */
+  sqlite3_vfs * const pVfs = pPager->pVfs;   /* Local cache of vfs pointer */
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-/*
-** If the cell pCell, part of page pPage contains a pointer
-** to an overflow page, insert an entry into the pointer-map
-** for the overflow page.
-*/
-static int ptrmapPutOvflPtr(MemPage *pPage, u8 *pCell){
-  if( pCell ){
-    CellInfo info;
-    sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-    assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
-    if( (info.nData+(pPage->intKey?0:info.nKey))>info.nLocal ){
-      Pgno ovfl = get4byte(&pCell[info.iOverflow]);
-      return ptrmapPut(pPage->pBt, ovfl, PTRMAP_OVERFLOW1, pPage->pgno);
+  assert( pPager->state>=PAGER_RESERVED );
+  assert( pPager->useJournal );
+  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF );
+  assert( pPager->pInJournal==0 );
+  
+  /* If already in the error state, this function is a no-op.  But on
+  ** the other hand, this routine is never called if we are already in
+  ** an error state. */
+  if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+  /* TODO: Is it really possible to get here with dbSizeValid==0? If not,
+  ** the call to PagerPagecount() can be removed.
+  */
+  testcase( pPager->dbSizeValid==0 );
+  sqlite3PagerPagecount(pPager, 0);
+
+  pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
+  if( pPager->pInJournal==0 ){
+    return SQLITE_NOMEM;
+  }
+
+  /* Open the journal file if it is not already open. */
+  if( !isOpen(pPager->jfd) ){
+    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
+      sqlite3MemJournalOpen(pPager->jfd);
+    }else{
+      const int flags =                   /* VFS flags to open journal file */
+        SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
+        (pPager->tempFile ? 
+          (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
+          (SQLITE_OPEN_MAIN_JOURNAL)
+        );
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+      rc = sqlite3JournalOpen(
+          pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
+      );
+#else
+      rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
+#endif
     }
+    assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
   }
-  return SQLITE_OK;
+
+
+  /* Write the first journal header to the journal file and open 
+  ** the sub-journal if necessary.
+  */
+  if( rc==SQLITE_OK ){
+    /* TODO: Check if all of these are really required. */
+    pPager->dbOrigSize = pPager->dbSize;
+    pPager->journalStarted = 0;
+    pPager->needSync = 0;
+    pPager->nRec = 0;
+    pPager->journalOff = 0;
+    pPager->setMaster = 0;
+    pPager->journalHdr = 0;
+    rc = writeJournalHdr(pPager);
+  }
+  if( rc==SQLITE_OK && pPager->nSavepoint ){
+    rc = openSubJournal(pPager);
+  }
+
+  if( rc!=SQLITE_OK ){
+    sqlite3BitvecDestroy(pPager->pInJournal);
+    pPager->pInJournal = 0;
+  }
+  return rc;
 }
+
 /*
-** If the cell with index iCell on page pPage contains a pointer
-** to an overflow page, insert an entry into the pointer-map
-** for the overflow page.
+** Begin a write-transaction on the specified pager object. If a 
+** write-transaction has already been opened, this function is a no-op.
+**
+** If the exFlag argument is false, then acquire at least a RESERVED
+** lock on the database file. If exFlag is true, then acquire at least
+** an EXCLUSIVE lock. If such a lock is already held, no locking 
+** functions need be called.
+**
+** If this is not a temporary or in-memory file and, the journal file is 
+** opened if it has not been already. For a temporary file, the opening 
+** of the journal file is deferred until there is an actual need to 
+** write to the journal. TODO: Why handle temporary files differently?
+**
+** If the journal file is opened (or if it is already open), then a
+** journal-header is written to the start of it.
+**
+** If the subjInMemory argument is non-zero, then any sub-journal opened
+** within this transaction will be opened as an in-memory file. This
+** has no effect if the sub-journal is already opened (as it may be when
+** running in exclusive mode) or if the transaction does not require a
+** sub-journal. If the subjInMemory argument is zero, then any required
+** sub-journal is implemented in-memory if pPager is an in-memory database, 
+** or using a temporary file otherwise.
 */
-static int ptrmapPutOvfl(MemPage *pPage, int iCell){
-  u8 *pCell;
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  pCell = findOverflowCell(pPage, iCell);
-  return ptrmapPutOvflPtr(pPage, pCell);
-}
-#endif
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager *pPager, int exFlag, int subjInMemory){
+  int rc = SQLITE_OK;
+  assert( pPager->state!=PAGER_UNLOCK );
+  pPager->subjInMemory = (u8)subjInMemory;
+  if( pPager->state==PAGER_SHARED ){
+    assert( pPager->pInJournal==0 );
+    assert( !MEMDB && !pPager->tempFile );
 
+    /* Obtain a RESERVED lock on the database file. If the exFlag parameter
+    ** is true, then immediately upgrade this to an EXCLUSIVE lock. The
+    ** busy-handler callback can be used when upgrading to the EXCLUSIVE
+    ** lock, but not when obtaining the RESERVED lock.
+    */
+    rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
+    if( rc==SQLITE_OK ){
+      pPager->state = PAGER_RESERVED;
+      if( exFlag ){
+        rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+      }
+    }
 
-/*
-** Defragment the page given.  All Cells are moved to the
-** end of the page and all free space is collected into one
-** big FreeBlk that occurs in between the header and cell
-** pointer array and the cell content area.
-*/
-static int defragmentPage(MemPage *pPage){
-  int i;                     /* Loop counter */
-  int pc;                    /* Address of a i-th cell */
-  int addr;                  /* Offset of first byte after cell pointer array */
-  int hdr;                   /* Offset to the page header */
-  int size;                  /* Size of a cell */
-  int usableSize;            /* Number of usable bytes on a page */
-  int cellOffset;            /* Offset to the cell pointer array */
-  int brk;                   /* Offset to the cell content area */
-  int nCell;                 /* Number of cells on the page */
-  unsigned char *data;       /* The page data */
-  unsigned char *temp;       /* Temp area for cell content */
+    /* If the required locks were successfully obtained, open the journal
+    ** file and write the first journal-header to it.
+    */
+    if( rc==SQLITE_OK && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+      rc = pager_open_journal(pPager);
+    }
+  }else if( isOpen(pPager->jfd) && pPager->journalOff==0 ){
+    /* This happens when the pager was in exclusive-access mode the last
+    ** time a (read or write) transaction was successfully concluded
+    ** by this connection. Instead of deleting the journal file it was 
+    ** kept open and either was truncated to 0 bytes or its header was
+    ** overwritten with zeros.
+    */
+    assert( pPager->nRec==0 );
+    assert( pPager->dbOrigSize==0 );
+    assert( pPager->pInJournal==0 );
+    rc = pager_open_journal(pPager);
+  }
 
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-  assert( pPage->pBt!=0 );
-  assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
-  assert( pPage->nOverflow==0 );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  temp = sqlite3PagerTempSpace(pPage->pBt->pPager);
-  data = pPage->aData;
-  hdr = pPage->hdrOffset;
-  cellOffset = pPage->cellOffset;
-  nCell = pPage->nCell;
-  assert( nCell==get2byte(&data[hdr+3]) );
-  usableSize = pPage->pBt->usableSize;
-  brk = get2byte(&data[hdr+5]);
-  memcpy(&temp[brk], &data[brk], usableSize - brk);
-  brk = usableSize;
-  for(i=0; i<nCell; i++){
-    u8 *pAddr;     /* The i-th cell pointer */
-    pAddr = &data[cellOffset + i*2];
-    pc = get2byte(pAddr);
-    assert( pc<pPage->pBt->usableSize );
-    size = cellSizePtr(pPage, &temp[pc]);
-    brk -= size;
-    memcpy(&data[brk], &temp[pc], size);
-    put2byte(pAddr, brk);
+  PAGERTRACE(("TRANSACTION %d\n", PAGERID(pPager)));
+  assert( !isOpen(pPager->jfd) || pPager->journalOff>0 || rc!=SQLITE_OK );
+  if( rc!=SQLITE_OK ){
+    assert( !pPager->dbModified );
+    /* Ignore any IO error that occurs within pager_end_transaction(). The
+    ** purpose of this call is to reset the internal state of the pager
+    ** sub-system. It doesn't matter if the journal-file is not properly
+    ** finalized at this point (since it is not a valid journal file anyway).
+    */
+    pager_end_transaction(pPager, 0);
   }
-  assert( brk>=cellOffset+2*nCell );
-  put2byte(&data[hdr+5], brk);
-  data[hdr+1] = 0;
-  data[hdr+2] = 0;
-  data[hdr+7] = 0;
-  addr = cellOffset+2*nCell;
-  memset(&data[addr], 0, brk-addr);
-  return SQLITE_OK;
+  return rc;
 }
 
 /*
-** Allocate nByte bytes of space on a page.
-**
-** Return the index into pPage->aData[] of the first byte of
-** the new allocation. Or return 0 if there is not enough free
-** space on the page to satisfy the allocation request.
-**
-** If the page contains nBytes of free space but does not contain
-** nBytes of contiguous free space, then this routine automatically
-** calls defragementPage() to consolidate all free space before 
-** allocating the new chunk.
+** Mark a single data page as writeable. The page is written into the 
+** main journal or sub-journal as required. If the page is written into
+** one of the journals, the corresponding bit is set in the 
+** Pager.pInJournal bitvec and the PagerSavepoint.pInSavepoint bitvecs
+** of any open savepoints as appropriate.
 */
-static int allocateSpace(MemPage *pPage, int nByte){
-  int addr, pc, hdr;
-  int size;
-  int nFrag;
-  int top;
-  int nCell;
-  int cellOffset;
-  unsigned char *data;
+static int pager_write(PgHdr *pPg){
+  void *pData = pPg->pData;
+  Pager *pPager = pPg->pPager;
+  int rc = SQLITE_OK;
+
+  /* This routine is not called unless a transaction has already been
+  ** started.
+  */
+  assert( pPager->state>=PAGER_RESERVED );
+
+  /* If an error has been previously detected, we should not be
+  ** calling this routine.  Repeat the error for robustness.
+  */
+  if( NEVER(pPager->errCode) )  return pPager->errCode;
+
+  /* Higher-level routines never call this function if database is not
+  ** writable.  But check anyway, just for robustness. */
+  if( NEVER(pPager->readOnly) ) return SQLITE_PERM;
+
+  assert( !pPager->setMaster );
+
+  CHECK_PAGE(pPg);
+
+  /* Mark the page as dirty.  If the page has already been written
+  ** to the journal then we can return right away.
+  */
+  sqlite3PcacheMakeDirty(pPg);
+  if( pageInJournal(pPg) && !subjRequiresPage(pPg) ){
+    pPager->dbModified = 1;
+  }else{
+
+    /* If we get this far, it means that the page needs to be
+    ** written to the transaction journal or the ckeckpoint journal
+    ** or both.
+    **
+    ** Higher level routines should have already started a transaction,
+    ** which means they have acquired the necessary locks and opened
+    ** a rollback journal.  Double-check to makes sure this is the case.
+    */
+    rc = sqlite3PagerBegin(pPager, 0, pPager->subjInMemory);
+    if( NEVER(rc!=SQLITE_OK) ){
+      return rc;
+    }
+    if( !isOpen(pPager->jfd) && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+      assert( pPager->useJournal );
+      rc = pager_open_journal(pPager);
+      if( rc!=SQLITE_OK ) return rc;
+    }
+    pPager->dbModified = 1;
   
-  data = pPage->aData;
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-  assert( pPage->pBt );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( nByte<4 ) nByte = 4;
-  if( pPage->nFree<nByte || pPage->nOverflow>0 ) return 0;
-  pPage->nFree -= nByte;
-  hdr = pPage->hdrOffset;
+    /* The transaction journal now exists and we have a RESERVED or an
+    ** EXCLUSIVE lock on the main database file.  Write the current page to
+    ** the transaction journal if it is not there already.
+    */
+    if( !pageInJournal(pPg) && isOpen(pPager->jfd) ){
+      if( pPg->pgno<=pPager->dbOrigSize ){
+        u32 cksum;
+        char *pData2;
+
+        /* We should never write to the journal file the page that
+        ** contains the database locks.  The following assert verifies
+        ** that we do not. */
+        assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
+        CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
+        cksum = pager_cksum(pPager, (u8*)pData2);
+        rc = write32bits(pPager->jfd, pPager->journalOff, pPg->pgno);
+        if( rc==SQLITE_OK ){
+          rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize,
+                              pPager->journalOff + 4);
+          pPager->journalOff += pPager->pageSize+4;
+        }
+        if( rc==SQLITE_OK ){
+          rc = write32bits(pPager->jfd, pPager->journalOff, cksum);
+          pPager->journalOff += 4;
+        }
+        IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno, 
+                 pPager->journalOff, pPager->pageSize));
+        PAGER_INCR(sqlite3_pager_writej_count);
+        PAGERTRACE(("JOURNAL %d page %d needSync=%d hash(%08x)\n",
+             PAGERID(pPager), pPg->pgno, 
+             ((pPg->flags&PGHDR_NEED_SYNC)?1:0), pager_pagehash(pPg)));
+
+        /* Even if an IO or diskfull error occurred while journalling the
+        ** page in the block above, set the need-sync flag for the page.
+        ** Otherwise, when the transaction is rolled back, the logic in
+        ** playback_one_page() will think that the page needs to be restored
+        ** in the database file. And if an IO error occurs while doing so,
+        ** then corruption may follow.
+        */
+        if( !pPager->noSync ){
+          pPg->flags |= PGHDR_NEED_SYNC;
+          pPager->needSync = 1;
+        }
 
-  nFrag = data[hdr+7];
-  if( nFrag<60 ){
-    /* Search the freelist looking for a slot big enough to satisfy the
-    ** space request. */
-    addr = hdr+1;
-    while( (pc = get2byte(&data[addr]))>0 ){
-      size = get2byte(&data[pc+2]);
-      if( size>=nByte ){
-        if( size<nByte+4 ){
-          memcpy(&data[addr], &data[pc], 2);
-          data[hdr+7] = nFrag + size - nByte;
-          return pc;
-        }else{
-          put2byte(&data[pc+2], size-nByte);
-          return pc + size - nByte;
+        /* An error has occurred writing to the journal file. The 
+        ** transaction will be rolled back by the layer above.
+        */
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+
+        pPager->nRec++;
+        assert( pPager->pInJournal!=0 );
+        rc = sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
+        testcase( rc==SQLITE_NOMEM );
+        assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+        rc |= addToSavepointBitvecs(pPager, pPg->pgno);
+        if( rc!=SQLITE_OK ){
+          assert( rc==SQLITE_NOMEM );
+          return rc;
+        }
+      }else{
+        if( !pPager->journalStarted && !pPager->noSync ){
+          pPg->flags |= PGHDR_NEED_SYNC;
+          pPager->needSync = 1;
         }
+        PAGERTRACE(("APPEND %d page %d needSync=%d\n",
+                PAGERID(pPager), pPg->pgno,
+               ((pPg->flags&PGHDR_NEED_SYNC)?1:0)));
       }
-      addr = pc;
+    }
+  
+    /* If the statement journal is open and the page is not in it,
+    ** then write the current page to the statement journal.  Note that
+    ** the statement journal format differs from the standard journal format
+    ** in that it omits the checksums and the header.
+    */
+    if( subjRequiresPage(pPg) ){
+      rc = subjournalPage(pPg);
     }
   }
 
-  /* Allocate memory from the gap in between the cell pointer array
-  ** and the cell content area.
+  /* Update the database size and return.
   */
-  top = get2byte(&data[hdr+5]);
-  nCell = get2byte(&data[hdr+3]);
-  cellOffset = pPage->cellOffset;
-  if( nFrag>=60 || cellOffset + 2*nCell > top - nByte ){
-    if( defragmentPage(pPage) ) return 0;
-    top = get2byte(&data[hdr+5]);
+  assert( pPager->state>=PAGER_SHARED );
+  if( pPager->dbSize<pPg->pgno ){
+    pPager->dbSize = pPg->pgno;
   }
-  top -= nByte;
-  assert( cellOffset + 2*nCell <= top );
-  put2byte(&data[hdr+5], top);
-  return top;
+  return rc;
 }
 
 /*
-** Return a section of the pPage->aData to the freelist.
-** The first byte of the new free block is pPage->aDisk[start]
-** and the size of the block is "size" bytes.
+** Mark a data page as writeable. This routine must be called before 
+** making changes to a page. The caller must check the return value 
+** of this function and be careful not to change any page data unless 
+** this routine returns SQLITE_OK.
 **
-** Most of the effort here is involved in coalesing adjacent
-** free blocks into a single big free block.
+** The difference between this function and pager_write() is that this
+** function also deals with the special case where 2 or more pages
+** fit on a single disk sector. In this case all co-resident pages
+** must have been written to the journal file before returning.
+**
+** If an error occurs, SQLITE_NOMEM or an IO error code is returned
+** as appropriate. Otherwise, SQLITE_OK.
 */
-static void freeSpace(MemPage *pPage, int start, int size){
-  int addr, pbegin, hdr;
-  unsigned char *data = pPage->aData;
+SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
+  int rc = SQLITE_OK;
 
-  assert( pPage->pBt!=0 );
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-  assert( start>=pPage->hdrOffset+6+(pPage->leaf?0:4) );
-  assert( (start + size)<=pPage->pBt->usableSize );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( size<4 ) size = 4;
+  PgHdr *pPg = pDbPage;
+  Pager *pPager = pPg->pPager;
+  Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
 
-#ifdef SQLITE_SECURE_DELETE
-  /* Overwrite deleted information with zeros when the SECURE_DELETE 
-  ** option is enabled at compile-time */
-  memset(&data[start], 0, size);
-#endif
+  if( nPagePerSector>1 ){
+    Pgno nPageCount;          /* Total number of pages in database file */
+    Pgno pg1;                 /* First page of the sector pPg is located on. */
+    int nPage;                /* Number of pages starting at pg1 to journal */
+    int ii;                   /* Loop counter */
+    int needSync = 0;         /* True if any page has PGHDR_NEED_SYNC */
 
-  /* Add the space back into the linked list of freeblocks */
-  hdr = pPage->hdrOffset;
-  addr = hdr + 1;
-  while( (pbegin = get2byte(&data[addr]))<start && pbegin>0 ){
-    assert( pbegin<=pPage->pBt->usableSize-4 );
-    assert( pbegin>addr );
-    addr = pbegin;
-  }
-  assert( pbegin<=pPage->pBt->usableSize-4 );
-  assert( pbegin>addr || pbegin==0 );
-  put2byte(&data[addr], start);
-  put2byte(&data[start], pbegin);
-  put2byte(&data[start+2], size);
-  pPage->nFree += size;
+    /* Set the doNotSync flag to 1. This is because we cannot allow a journal
+    ** header to be written between the pages journaled by this function.
+    */
+    assert( !MEMDB );
+    assert( pPager->doNotSync==0 );
+    pPager->doNotSync = 1;
 
-  /* Coalesce adjacent free blocks */
-  addr = pPage->hdrOffset + 1;
-  while( (pbegin = get2byte(&data[addr]))>0 ){
-    int pnext, psize;
-    assert( pbegin>addr );
-    assert( pbegin<=pPage->pBt->usableSize-4 );
-    pnext = get2byte(&data[pbegin]);
-    psize = get2byte(&data[pbegin+2]);
-    if( pbegin + psize + 3 >= pnext && pnext>0 ){
-      int frag = pnext - (pbegin+psize);
-      assert( frag<=data[pPage->hdrOffset+7] );
-      data[pPage->hdrOffset+7] -= frag;
-      put2byte(&data[pbegin], get2byte(&data[pnext]));
-      put2byte(&data[pbegin+2], pnext+get2byte(&data[pnext+2])-pbegin);
+    /* This trick assumes that both the page-size and sector-size are
+    ** an integer power of 2. It sets variable pg1 to the identifier
+    ** of the first page of the sector pPg is located on.
+    */
+    pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
+
+    sqlite3PagerPagecount(pPager, (int *)&nPageCount);
+    if( pPg->pgno>nPageCount ){
+      nPage = (pPg->pgno - pg1)+1;
+    }else if( (pg1+nPagePerSector-1)>nPageCount ){
+      nPage = nPageCount+1-pg1;
     }else{
-      addr = pbegin;
+      nPage = nPagePerSector;
     }
-  }
+    assert(nPage>0);
+    assert(pg1<=pPg->pgno);
+    assert((pg1+nPage)>pPg->pgno);
 
-  /* If the cell content area begins with a freeblock, remove it. */
-  if( data[hdr+1]==data[hdr+5] && data[hdr+2]==data[hdr+6] ){
-    int top;
-    pbegin = get2byte(&data[hdr+1]);
-    memcpy(&data[hdr+1], &data[pbegin], 2);
-    top = get2byte(&data[hdr+5]);
-    put2byte(&data[hdr+5], top + get2byte(&data[pbegin+2]));
+    for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
+      Pgno pg = pg1+ii;
+      PgHdr *pPage;
+      if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
+        if( pg!=PAGER_MJ_PGNO(pPager) ){
+          rc = sqlite3PagerGet(pPager, pg, &pPage);
+          if( rc==SQLITE_OK ){
+            rc = pager_write(pPage);
+            if( pPage->flags&PGHDR_NEED_SYNC ){
+              needSync = 1;
+              assert(pPager->needSync);
+            }
+            sqlite3PagerUnref(pPage);
+          }
+        }
+      }else if( (pPage = pager_lookup(pPager, pg))!=0 ){
+        if( pPage->flags&PGHDR_NEED_SYNC ){
+          needSync = 1;
+        }
+        sqlite3PagerUnref(pPage);
+      }
+    }
+
+    /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages 
+    ** starting at pg1, then it needs to be set for all of them. Because
+    ** writing to any of these nPage pages may damage the others, the
+    ** journal file must contain sync()ed copies of all of them
+    ** before any of them can be written out to the database file.
+    */
+    if( rc==SQLITE_OK && needSync ){
+      assert( !MEMDB && pPager->noSync==0 );
+      for(ii=0; ii<nPage; ii++){
+        PgHdr *pPage = pager_lookup(pPager, pg1+ii);
+        if( pPage ){
+          pPage->flags |= PGHDR_NEED_SYNC;
+          sqlite3PagerUnref(pPage);
+        }
+      }
+      assert(pPager->needSync);
+    }
+
+    assert( pPager->doNotSync==1 );
+    pPager->doNotSync = 0;
+  }else{
+    rc = pager_write(pDbPage);
   }
+  return rc;
 }
 
 /*
-** Decode the flags byte (the first byte of the header) for a page
-** and initialize fields of the MemPage structure accordingly.
+** Return TRUE if the page given in the argument was previously passed
+** to sqlite3PagerWrite().  In other words, return TRUE if it is ok
+** to change the content of the page.
 */
-static void decodeFlags(MemPage *pPage, int flagByte){
-  BtShared *pBt;     /* A copy of pPage->pBt */
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage *pPg){
+  return pPg->flags&PGHDR_DIRTY;
+}
+#endif
 
-  assert( pPage->hdrOffset==(pPage->pgno==1 ? 100 : 0) );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  pPage->intKey = (flagByte & (PTF_INTKEY|PTF_LEAFDATA))!=0;
-  pPage->zeroData = (flagByte & PTF_ZERODATA)!=0;
-  pPage->leaf = (flagByte & PTF_LEAF)!=0;
-  pPage->childPtrSize = 4*(pPage->leaf==0);
-  pBt = pPage->pBt;
-  if( flagByte & PTF_LEAFDATA ){
-    pPage->leafData = 1;
-    pPage->maxLocal = pBt->maxLeaf;
-    pPage->minLocal = pBt->minLeaf;
-  }else{
-    pPage->leafData = 0;
-    pPage->maxLocal = pBt->maxLocal;
-    pPage->minLocal = pBt->minLocal;
+/*
+** A call to this routine tells the pager that it is not necessary to
+** write the information on page pPg back to the disk, even though
+** that page might be marked as dirty.  This happens, for example, when
+** the page has been added as a leaf of the freelist and so its
+** content no longer matters.
+**
+** The overlying software layer calls this routine when all of the data
+** on the given page is unused. The pager marks the page as clean so
+** that it does not get written to disk.
+**
+** Tests show that this optimization can quadruple the speed of large 
+** DELETE operations.
+*/
+SQLITE_PRIVATE void sqlite3PagerDontWrite(PgHdr *pPg){
+  Pager *pPager = pPg->pPager;
+  if( (pPg->flags&PGHDR_DIRTY) && pPager->nSavepoint==0 ){
+    PAGERTRACE(("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager)));
+    IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
+    pPg->flags |= PGHDR_DONT_WRITE;
+#ifdef SQLITE_CHECK_PAGES
+    pPg->pageHash = pager_pagehash(pPg);
+#endif
   }
-  pPage->hasData = !(pPage->zeroData || (!pPage->leaf && pPage->leafData));
 }
 
 /*
-** Initialize the auxiliary information for a disk block.
+** This routine is called to increment the value of the database file 
+** change-counter, stored as a 4-byte big-endian integer starting at 
+** byte offset 24 of the pager file.
 **
-** The pParent parameter must be a pointer to the MemPage which
-** is the parent of the page being initialized.  The root of a
-** BTree has no parent and so for that page, pParent==NULL.
+** If the isDirectMode flag is zero, then this is done by calling 
+** sqlite3PagerWrite() on page 1, then modifying the contents of the
+** page data. In this case the file will be updated when the current
+** transaction is committed.
 **
-** Return SQLITE_OK on success.  If we see that the page does
-** not contain a well-formed database page, then return 
-** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
-** guarantee that the page is well-formed.  It only shows that
-** we failed to detect any corruption.
+** The isDirectMode flag may only be non-zero if the library was compiled
+** with the SQLITE_ENABLE_ATOMIC_WRITE macro defined. In this case,
+** if isDirect is non-zero, then the database file is updated directly
+** by writing an updated version of page 1 using a call to the 
+** sqlite3OsWrite() function.
 */
-SQLITE_PRIVATE int sqlite3BtreeInitPage(
-  MemPage *pPage,        /* The page to be initialized */
-  MemPage *pParent       /* The parent.  Might be NULL */
-){
-  int pc;            /* Address of a freeblock within pPage->aData[] */
-  int hdr;           /* Offset to beginning of page header */
-  u8 *data;          /* Equal to pPage->aData */
-  BtShared *pBt;        /* The main btree structure */
-  int usableSize;    /* Amount of usable space on each page */
-  int cellOffset;    /* Offset from start of page to first cell pointer */
-  int nFree;         /* Number of unused bytes on the page */
-  int top;           /* First byte of the cell content area */
+static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
+  int rc = SQLITE_OK;
 
-  pBt = pPage->pBt;
-  assert( pBt!=0 );
-  assert( pParent==0 || pParent->pBt==pBt );
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
-  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
-  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
-  if( pPage->pParent!=pParent && (pPage->pParent!=0 || pPage->isInit) ){
-    /* The parent page should never change unless the file is corrupt */
-    return SQLITE_CORRUPT_BKPT;
-  }
-  if( pPage->isInit ) return SQLITE_OK;
-  if( pPage->pParent==0 && pParent!=0 ){
-    pPage->pParent = pParent;
-    sqlite3PagerRef(pParent->pDbPage);
-  }
-  hdr = pPage->hdrOffset;
-  data = pPage->aData;
-  decodeFlags(pPage, data[hdr]);
-  pPage->nOverflow = 0;
-  pPage->idxShift = 0;
-  usableSize = pBt->usableSize;
-  pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
-  top = get2byte(&data[hdr+5]);
-  pPage->nCell = get2byte(&data[hdr+3]);
-  if( pPage->nCell>MX_CELL(pBt) ){
-    /* To many cells for a single page.  The page must be corrupt */
-    return SQLITE_CORRUPT_BKPT;
-  }
-  if( pPage->nCell==0 && pParent!=0 && pParent->pgno!=1 ){
-    /* All pages must have at least one cell, except for root pages */
-    return SQLITE_CORRUPT_BKPT;
-  }
+  /* Declare and initialize constant integer 'isDirect'. If the
+  ** atomic-write optimization is enabled in this build, then isDirect
+  ** is initialized to the value passed as the isDirectMode parameter
+  ** to this function. Otherwise, it is always set to zero.
+  **
+  ** The idea is that if the atomic-write optimization is not
+  ** enabled at compile time, the compiler can omit the tests of
+  ** 'isDirect' below, as well as the block enclosed in the
+  ** "if( isDirect )" condition.
+  */
+#ifndef SQLITE_ENABLE_ATOMIC_WRITE
+# define DIRECT_MODE 0
+  assert( isDirectMode==0 );
+  UNUSED_PARAMETER(isDirectMode);
+#else
+# define DIRECT_MODE isDirectMode
+#endif
 
-  /* Compute the total free space on the page */
-  pc = get2byte(&data[hdr+1]);
-  nFree = data[hdr+7] + top - (cellOffset + 2*pPage->nCell);
-  while( pc>0 ){
-    int next, size;
-    if( pc>usableSize-4 ){
-      /* Free block is off the page */
-      return SQLITE_CORRUPT_BKPT; 
+  assert( pPager->state>=PAGER_RESERVED );
+  if( !pPager->changeCountDone && ALWAYS(pPager->dbSize>0) ){
+    PgHdr *pPgHdr;                /* Reference to page 1 */
+    u32 change_counter;           /* Initial value of change-counter field */
+
+    assert( !pPager->tempFile && isOpen(pPager->fd) );
+
+    /* Open page 1 of the file for writing. */
+    rc = sqlite3PagerGet(pPager, 1, &pPgHdr);
+    assert( pPgHdr==0 || rc==SQLITE_OK );
+
+    /* If page one was fetched successfully, and this function is not
+    ** operating in direct-mode, make page 1 writable.  When not in 
+    ** direct mode, page 1 is always held in cache and hence the PagerGet()
+    ** above is always successful - hence the ALWAYS on rc==SQLITE_OK.
+    */
+    if( !DIRECT_MODE && ALWAYS(rc==SQLITE_OK) ){
+      rc = sqlite3PagerWrite(pPgHdr);
     }
-    next = get2byte(&data[pc]);
-    size = get2byte(&data[pc+2]);
-    if( next>0 && next<=pc+size+3 ){
-      /* Free blocks must be in accending order */
-      return SQLITE_CORRUPT_BKPT; 
+
+    if( rc==SQLITE_OK ){
+      /* Increment the value just read and write it back to byte 24. */
+      change_counter = sqlite3Get4byte((u8*)pPager->dbFileVers);
+      change_counter++;
+      put32bits(((char*)pPgHdr->pData)+24, change_counter);
+
+      /* If running in direct mode, write the contents of page 1 to the file. */
+      if( DIRECT_MODE ){
+        const void *zBuf = pPgHdr->pData;
+        assert( pPager->dbFileSize>0 );
+        rc = sqlite3OsWrite(pPager->fd, zBuf, pPager->pageSize, 0);
+        if( rc==SQLITE_OK ){
+          pPager->changeCountDone = 1;
+        }
+      }else{
+        pPager->changeCountDone = 1;
+      }
     }
-    nFree += size;
-    pc = next;
-  }
-  pPage->nFree = nFree;
-  if( nFree>=usableSize ){
-    /* Free space cannot exceed total page size */
-    return SQLITE_CORRUPT_BKPT; 
-  }
 
-  pPage->isInit = 1;
-  return SQLITE_OK;
+    /* Release the page reference. */
+    sqlite3PagerUnref(pPgHdr);
+  }
+  return rc;
 }
 
 /*
-** Set up a raw page so that it looks like a database page holding
-** no entries.
+** Sync the pager file to disk. This is a no-op for in-memory files
+** or pages with the Pager.noSync flag set.
+**
+** If successful, or called on a pager for which it is a no-op, this
+** function returns SQLITE_OK. Otherwise, an IO error code is returned.
 */
-static void zeroPage(MemPage *pPage, int flags){
-  unsigned char *data = pPage->aData;
-  BtShared *pBt = pPage->pBt;
-  int hdr = pPage->hdrOffset;
-  int first;
-
-  assert( sqlite3PagerPagenumber(pPage->pDbPage)==pPage->pgno );
-  assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
-  assert( sqlite3PagerGetData(pPage->pDbPage) == data );
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  memset(&data[hdr], 0, pBt->usableSize - hdr);
-  data[hdr] = flags;
-  first = hdr + 8 + 4*((flags&PTF_LEAF)==0);
-  memset(&data[hdr+1], 0, 4);
-  data[hdr+7] = 0;
-  put2byte(&data[hdr+5], pBt->usableSize);
-  pPage->nFree = pBt->usableSize - first;
-  decodeFlags(pPage, flags);
-  pPage->hdrOffset = hdr;
-  pPage->cellOffset = first;
-  pPage->nOverflow = 0;
-  pPage->idxShift = 0;
-  pPage->nCell = 0;
-  pPage->isInit = 1;
-}
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager){
+  int rc;                              /* Return code */
+  assert( !MEMDB );
+  if( pPager->noSync ){
+    rc = SQLITE_OK;
+  }else{
+    rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
+  }
+  return rc;
+}
 
 /*
-** Get a page from the pager.  Initialize the MemPage.pBt and
-** MemPage.aData elements if needed.
+** Sync the database file for the pager pPager. zMaster points to the name
+** of a master journal file that should be written into the individual
+** journal file. zMaster may be NULL, which is interpreted as no master
+** journal (a single database transaction).
 **
-** If the noContent flag is set, it means that we do not care about
-** the content of the page at this time.  So do not go to the disk
-** to fetch the content.  Just fill in the content with zeros for now.
-** If in the future we call sqlite3PagerWrite() on this page, that
-** means we have started to be concerned about content and the disk
-** read should occur at that point.
+** This routine ensures that:
+**
+**   * The database file change-counter is updated,
+**   * the journal is synced (unless the atomic-write optimization is used),
+**   * all dirty pages are written to the database file, 
+**   * the database file is truncated (if required), and
+**   * the database file synced. 
+**
+** The only thing that remains to commit the transaction is to finalize 
+** (delete, truncate or zero the first part of) the journal file (or 
+** delete the master journal file if specified).
+**
+** Note that if zMaster==NULL, this does not overwrite a previous value
+** passed to an sqlite3PagerCommitPhaseOne() call.
+**
+** If the final parameter - noSync - is true, then the database file itself
+** is not synced. The caller must call sqlite3PagerSync() directly to
+** sync the database file before calling CommitPhaseTwo() to delete the
+** journal file in this case.
 */
-SQLITE_PRIVATE int sqlite3BtreeGetPage(
-  BtShared *pBt,       /* The btree */
-  Pgno pgno,           /* Number of the page to fetch */
-  MemPage **ppPage,    /* Return the page in this parameter */
-  int noContent        /* Do not load page content if true */
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
+  Pager *pPager,                  /* Pager object */
+  const char *zMaster,            /* If not NULL, the master journal name */
+  int noSync                      /* True to omit the xSync on the db file */
 ){
-  int rc;
-  MemPage *pPage;
-  DbPage *pDbPage;
+  int rc = SQLITE_OK;             /* Return code */
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, noContent);
-  if( rc ) return rc;
-  pPage = (MemPage *)sqlite3PagerGetExtra(pDbPage);
-  pPage->aData = sqlite3PagerGetData(pDbPage);
-  pPage->pDbPage = pDbPage;
-  pPage->pBt = pBt;
-  pPage->pgno = pgno;
-  pPage->hdrOffset = pPage->pgno==1 ? 100 : 0;
-  *ppPage = pPage;
-  return SQLITE_OK;
-}
+  /* The dbOrigSize is never set if journal_mode=OFF */
+  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF || pPager->dbOrigSize==0 );
 
-/*
-** Get a page from the pager and initialize it.  This routine
-** is just a convenience wrapper around separate calls to
-** sqlite3BtreeGetPage() and sqlite3BtreeInitPage().
-*/
-static int getAndInitPage(
-  BtShared *pBt,          /* The database file */
-  Pgno pgno,           /* Number of the page to get */
-  MemPage **ppPage,    /* Write the page pointer here */
-  MemPage *pParent     /* Parent of the page */
-){
-  int rc;
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  if( pgno==0 ){
-    return SQLITE_CORRUPT_BKPT; 
-  }
-  rc = sqlite3BtreeGetPage(pBt, pgno, ppPage, 0);
-  if( rc==SQLITE_OK && (*ppPage)->isInit==0 ){
-    rc = sqlite3BtreeInitPage(*ppPage, pParent);
+  /* If a prior error occurred, this routine should not be called.  ROLLBACK
+  ** is the appropriate response to an error, not COMMIT.  Guard against
+  ** coding errors by repeating the prior error. */
+  if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+  PAGERTRACE(("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n", 
+      pPager->zFilename, zMaster, pPager->dbSize));
+
+  if( MEMDB && pPager->dbModified ){
+    /* If this is an in-memory db, or no pages have been written to, or this
+    ** function has already been called, it is mostly a no-op.  However, any
+    ** backup in progress needs to be restarted.
+    */
+    sqlite3BackupRestart(pPager->pBackup);
+  }else if( pPager->state!=PAGER_SYNCED && pPager->dbModified ){
+
+    /* The following block updates the change-counter. Exactly how it
+    ** does this depends on whether or not the atomic-update optimization
+    ** was enabled at compile time, and if this transaction meets the 
+    ** runtime criteria to use the operation: 
+    **
+    **    * The file-system supports the atomic-write property for
+    **      blocks of size page-size, and 
+    **    * This commit is not part of a multi-file transaction, and
+    **    * Exactly one page has been modified and store in the journal file.
+    **
+    ** If the optimization was not enabled at compile time, then the
+    ** pager_incr_changecounter() function is called to update the change
+    ** counter in 'indirect-mode'. If the optimization is compiled in but
+    ** is not applicable to this transaction, call sqlite3JournalCreate()
+    ** to make sure the journal file has actually been created, then call
+    ** pager_incr_changecounter() to update the change-counter in indirect
+    ** mode. 
+    **
+    ** Otherwise, if the optimization is both enabled and applicable,
+    ** then call pager_incr_changecounter() to update the change-counter
+    ** in 'direct' mode. In this case the journal file will never be
+    ** created for this transaction.
+    */
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+    PgHdr *pPg;
+    assert( isOpen(pPager->jfd) || pPager->journalMode==PAGER_JOURNALMODE_OFF );
+    if( !zMaster && isOpen(pPager->jfd) 
+     && pPager->journalOff==jrnlBufferSize(pPager) 
+     && pPager->dbSize>=pPager->dbFileSize
+     && (0==(pPg = sqlite3PcacheDirtyList(pPager->pPCache)) || 0==pPg->pDirty)
+    ){
+      /* Update the db file change counter via the direct-write method. The 
+      ** following call will modify the in-memory representation of page 1 
+      ** to include the updated change counter and then write page 1 
+      ** directly to the database file. Because of the atomic-write 
+      ** property of the host file-system, this is safe.
+      */
+      rc = pager_incr_changecounter(pPager, 1);
+    }else{
+      rc = sqlite3JournalCreate(pPager->jfd);
+      if( rc==SQLITE_OK ){
+        rc = pager_incr_changecounter(pPager, 0);
+      }
+    }
+#else
+    rc = pager_incr_changecounter(pPager, 0);
+#endif
+    if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+    /* If this transaction has made the database smaller, then all pages
+    ** being discarded by the truncation must be written to the journal
+    ** file. This can only happen in auto-vacuum mode.
+    **
+    ** Before reading the pages with page numbers larger than the 
+    ** current value of Pager.dbSize, set dbSize back to the value
+    ** that it took at the start of the transaction. Otherwise, the
+    ** calls to sqlite3PagerGet() return zeroed pages instead of 
+    ** reading data from the database file.
+    **
+    ** When journal_mode==OFF the dbOrigSize is always zero, so this
+    ** block never runs if journal_mode=OFF.
+    */
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pPager->dbSize<pPager->dbOrigSize 
+     && ALWAYS(pPager->journalMode!=PAGER_JOURNALMODE_OFF)
+    ){
+      Pgno i;                                   /* Iterator variable */
+      const Pgno iSkip = PAGER_MJ_PGNO(pPager); /* Pending lock page */
+      const Pgno dbSize = pPager->dbSize;       /* Database image size */ 
+      pPager->dbSize = pPager->dbOrigSize;
+      for( i=dbSize+1; i<=pPager->dbOrigSize; i++ ){
+        if( !sqlite3BitvecTest(pPager->pInJournal, i) && i!=iSkip ){
+          PgHdr *pPage;             /* Page to journal */
+          rc = sqlite3PagerGet(pPager, i, &pPage);
+          if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+          rc = sqlite3PagerWrite(pPage);
+          sqlite3PagerUnref(pPage);
+          if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+        }
+      } 
+      pPager->dbSize = dbSize;
+    }
+#endif
+
+    /* Write the master journal name into the journal file. If a master 
+    ** journal file name has already been written to the journal file, 
+    ** or if zMaster is NULL (no master journal), then this call is a no-op.
+    */
+    rc = writeMasterJournal(pPager, zMaster);
+    if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+    /* Sync the journal file. If the atomic-update optimization is being
+    ** used, this call will not create the journal file or perform any
+    ** real IO.
+    */
+    rc = syncJournal(pPager);
+    if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+    /* Write all dirty pages to the database file. */
+    rc = pager_write_pagelist(sqlite3PcacheDirtyList(pPager->pPCache));
     if( rc!=SQLITE_OK ){
-      releasePage(*ppPage);
-      *ppPage = 0;
+      assert( rc!=SQLITE_IOERR_BLOCKED );
+      goto commit_phase_one_exit;
+    }
+    sqlite3PcacheCleanAll(pPager->pPCache);
+
+    /* If the file on disk is not the same size as the database image,
+    ** then use pager_truncate to grow or shrink the file here.
+    */
+    if( pPager->dbSize!=pPager->dbFileSize ){
+      Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
+      assert( pPager->state>=PAGER_EXCLUSIVE );
+      rc = pager_truncate(pPager, nNew);
+      if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+    }
+
+    /* Finally, sync the database file. */
+    if( !pPager->noSync && !noSync ){
+      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
     }
+    IOTRACE(("DBSYNC %p\n", pPager))
+
+    pPager->state = PAGER_SYNCED;
   }
+
+commit_phase_one_exit:
   return rc;
 }
 
+
 /*
-** Release a MemPage.  This should be called once for each prior
-** call to sqlite3BtreeGetPage.
+** When this function is called, the database file has been completely
+** updated to reflect the changes made by the current transaction and
+** synced to disk. The journal file still exists in the file-system 
+** though, and if a failure occurs at this point it will eventually
+** be used as a hot-journal and the current transaction rolled back.
+**
+** This function finalizes the journal file, either by deleting, 
+** truncating or partially zeroing it, so that it cannot be used 
+** for hot-journal rollback. Once this is done the transaction is
+** irrevocably committed.
+**
+** If an error occurs, an IO error code is returned and the pager
+** moves into the error state. Otherwise, SQLITE_OK is returned.
 */
-static void releasePage(MemPage *pPage){
-  if( pPage ){
-    assert( pPage->aData );
-    assert( pPage->pBt );
-    assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
-    assert( sqlite3PagerGetData(pPage->pDbPage)==pPage->aData );
-    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-    sqlite3PagerUnref(pPage->pDbPage);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager *pPager){
+  int rc = SQLITE_OK;                  /* Return code */
+
+  /* This routine should not be called if a prior error has occurred.
+  ** But if (due to a coding error elsewhere in the system) it does get
+  ** called, just return the same error code without doing anything. */
+  if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+  /* This function should not be called if the pager is not in at least
+  ** PAGER_RESERVED state. And indeed SQLite never does this. But it is
+  ** nice to have this defensive test here anyway.
+  */
+  if( NEVER(pPager->state<PAGER_RESERVED) ) return SQLITE_ERROR;
+
+  /* An optimization. If the database was not actually modified during
+  ** this transaction, the pager is running in exclusive-mode and is
+  ** using persistent journals, then this function is a no-op.
+  **
+  ** The start of the journal file currently contains a single journal 
+  ** header with the nRec field set to 0. If such a journal is used as
+  ** a hot-journal during hot-journal rollback, 0 changes will be made
+  ** to the database file. So there is no need to zero the journal 
+  ** header. Since the pager is in exclusive mode, there is no need
+  ** to drop any locks either.
+  */
+  if( pPager->dbModified==0 && pPager->exclusiveMode 
+   && pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+  ){
+    assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) );
+    return SQLITE_OK;
   }
+
+  PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
+  assert( pPager->state==PAGER_SYNCED || MEMDB || !pPager->dbModified );
+  rc = pager_end_transaction(pPager, pPager->setMaster);
+  return pager_error(pPager, rc);
 }
 
 /*
-** This routine is called when the reference count for a page
-** reaches zero.  We need to unref the pParent pointer when that
-** happens.
+** Rollback all changes. The database falls back to PAGER_SHARED mode.
+**
+** This function performs two tasks:
+**
+**   1) It rolls back the journal file, restoring all database file and 
+**      in-memory cache pages to the state they were in when the transaction
+**      was opened, and
+**   2) It finalizes the journal file, so that it is not used for hot
+**      rollback at any point in the future.
+**
+** subject to the following qualifications:
+**
+** * If the journal file is not yet open when this function is called,
+**   then only (2) is performed. In this case there is no journal file
+**   to roll back.
+**
+** * If in an error state other than SQLITE_FULL, then task (1) is 
+**   performed. If successful, task (2). Regardless of the outcome
+**   of either, the error state error code is returned to the caller
+**   (i.e. either SQLITE_IOERR or SQLITE_CORRUPT).
+**
+** * If the pager is in PAGER_RESERVED state, then attempt (1). Whether
+**   or not (1) is succussful, also attempt (2). If successful, return
+**   SQLITE_OK. Otherwise, enter the error state and return the first 
+**   error code encountered. 
+**
+**   In this case there is no chance that the database was written to. 
+**   So is safe to finalize the journal file even if the playback 
+**   (operation 1) failed. However the pager must enter the error state
+**   as the contents of the in-memory cache are now suspect.
+**
+** * Finally, if in PAGER_EXCLUSIVE state, then attempt (1). Only
+**   attempt (2) if (1) is successful. Return SQLITE_OK if successful,
+**   otherwise enter the error state and return the error code from the 
+**   failing operation.
+**
+**   In this case the database file may have been written to. So if the
+**   playback operation did not succeed it would not be safe to finalize
+**   the journal file. It needs to be left in the file-system so that
+**   some other process can use it to restore the database state (by
+**   hot-journal rollback).
 */
-static void pageDestructor(DbPage *pData, int pageSize){
-  MemPage *pPage;
-  assert( (pageSize & 7)==0 );
-  pPage = (MemPage *)sqlite3PagerGetExtra(pData);
-  assert( pPage->isInit==0 || sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( pPage->pParent ){
-    MemPage *pParent = pPage->pParent;
-    assert( pParent->pBt==pPage->pBt );
-    pPage->pParent = 0;
-    releasePage(pParent);
+SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
+  int rc = SQLITE_OK;                  /* Return code */
+  PAGERTRACE(("ROLLBACK %d\n", PAGERID(pPager)));
+  if( !pPager->dbModified || !isOpen(pPager->jfd) ){
+    rc = pager_end_transaction(pPager, pPager->setMaster);
+  }else if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
+    if( pPager->state>=PAGER_EXCLUSIVE ){
+      pager_playback(pPager, 0);
+    }
+    rc = pPager->errCode;
+  }else{
+    if( pPager->state==PAGER_RESERVED ){
+      int rc2;
+      rc = pager_playback(pPager, 0);
+      rc2 = pager_end_transaction(pPager, pPager->setMaster);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }else{
+      rc = pager_playback(pPager, 0);
+    }
+
+    if( !MEMDB ){
+      pPager->dbSizeValid = 0;
+    }
+
+    /* If an error occurs during a ROLLBACK, we can no longer trust the pager
+    ** cache. So call pager_error() on the way out to make any error 
+    ** persistent.
+    */
+    rc = pager_error(pPager, rc);
   }
-  pPage->isInit = 0;
+  return rc;
 }
 
 /*
-** During a rollback, when the pager reloads information into the cache
-** so that the cache is restored to its original state at the start of
-** the transaction, for each page restored this routine is called.
-**
-** This routine needs to reset the extra data section at the end of the
-** page to agree with the restored data.
+** Return TRUE if the database file is opened read-only.  Return FALSE
+** if the database is (in theory) writable.
 */
-static void pageReinit(DbPage *pData, int pageSize){
-  MemPage *pPage;
-  assert( (pageSize & 7)==0 );
-  pPage = (MemPage *)sqlite3PagerGetExtra(pData);
-  if( pPage->isInit ){
-    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-    pPage->isInit = 0;
-    sqlite3BtreeInitPage(pPage, pPage->pParent);
-  }
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager *pPager){
+  return pPager->readOnly;
 }
 
 /*
-** Invoke the busy handler for a btree.
+** Return the number of references to the pager.
 */
-static int sqlite3BtreeInvokeBusyHandler(void *pArg, int n){
-  BtShared *pBt = (BtShared*)pArg;
-  assert( pBt->db );
-  assert( sqlite3_mutex_held(pBt->db->mutex) );
-  return sqlite3InvokeBusyHandler(&pBt->db->busyHandler);
+SQLITE_PRIVATE int sqlite3PagerRefcount(Pager *pPager){
+  return sqlite3PcacheRefCount(pPager->pPCache);
 }
 
 /*
-** Open a database file.
-** 
-** zFilename is the name of the database file.  If zFilename is NULL
-** a new database with a random name is created.  This randomly named
-** database file will be deleted when sqlite3BtreeClose() is called.
-** If zFilename is ":memory:" then an in-memory database is created
-** that is automatically destroyed when it is closed.
+** Return the number of references to the specified page.
 */
-SQLITE_PRIVATE int sqlite3BtreeOpen(
-  const char *zFilename,  /* Name of the file containing the BTree database */
-  sqlite3 *db,            /* Associated database handle */
-  Btree **ppBtree,        /* Pointer to new Btree object written here */
-  int flags,              /* Options */
-  int vfsFlags            /* Flags passed through to sqlite3_vfs.xOpen() */
-){
-  sqlite3_vfs *pVfs;      /* The VFS to use for this btree */
-  BtShared *pBt = 0;      /* Shared part of btree structure */
-  Btree *p;               /* Handle to return */
-  int rc = SQLITE_OK;
-  int nReserve;
-  unsigned char zDbHeader[100];
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage *pPage){
+  return sqlite3PcachePageRefcount(pPage);
+}
 
-  /* Set the variable isMemdb to true for an in-memory database, or 
-  ** false for a file-based database. This symbol is only required if
-  ** either of the shared-data or autovacuum features are compiled 
-  ** into the library.
-  */
-#if !defined(SQLITE_OMIT_SHARED_CACHE) || !defined(SQLITE_OMIT_AUTOVACUUM)
-  #ifdef SQLITE_OMIT_MEMORYDB
-    const int isMemdb = 0;
-  #else
-    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
-  #endif
+#ifdef SQLITE_TEST
+/*
+** This routine is used for testing and analysis only.
+*/
+SQLITE_PRIVATE int *sqlite3PagerStats(Pager *pPager){
+  static int a[11];
+  a[0] = sqlite3PcacheRefCount(pPager->pPCache);
+  a[1] = sqlite3PcachePagecount(pPager->pPCache);
+  a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
+  a[3] = pPager->dbSizeValid ? (int) pPager->dbSize : -1;
+  a[4] = pPager->state;
+  a[5] = pPager->errCode;
+  a[6] = pPager->nHit;
+  a[7] = pPager->nMiss;
+  a[8] = 0;  /* Used to be pPager->nOvfl */
+  a[9] = pPager->nRead;
+  a[10] = pPager->nWrite;
+  return a;
+}
 #endif
 
-  assert( db!=0 );
-  assert( sqlite3_mutex_held(db->mutex) );
+/*
+** Return true if this is an in-memory pager.
+*/
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager *pPager){
+  return MEMDB;
+}
 
-  pVfs = db->pVfs;
-  p = sqlite3MallocZero(sizeof(Btree));
-  if( !p ){
-    return SQLITE_NOMEM;
-  }
-  p->inTrans = TRANS_NONE;
-  p->db = db;
+/*
+** Check that there are at least nSavepoint savepoints open. If there are
+** currently less than nSavepoints open, then open one or more savepoints
+** to make up the difference. If the number of savepoints is already
+** equal to nSavepoint, then this function is a no-op.
+**
+** If a memory allocation fails, SQLITE_NOMEM is returned. If an error 
+** occurs while opening the sub-journal file, then an IO error code is
+** returned. Otherwise, SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int nSavepoint){
+  int rc = SQLITE_OK;                       /* Return code */
+  int nCurrent = pPager->nSavepoint;        /* Current number of savepoints */
 
-#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
-  /*
-  ** If this Btree is a candidate for shared cache, try to find an
-  ** existing BtShared object that we can share with
-  */
-  if( (flags & BTREE_PRIVATE)==0
-   && isMemdb==0
-   && (db->flags & SQLITE_Vtab)==0
-   && zFilename && zFilename[0]
-  ){
-    if( sqlite3SharedCacheEnabled ){
-      int nFullPathname = pVfs->mxPathname+1;
-      char *zFullPathname = (char *)sqlite3_malloc(nFullPathname);
-      sqlite3_mutex *mutexShared;
-      p->sharable = 1;
-      if( db ){
-        db->flags |= SQLITE_SharedCache;
-      }
-      if( !zFullPathname ){
-        sqlite3_free(p);
-        return SQLITE_NOMEM;
-      }
-      sqlite3OsFullPathname(pVfs, zFilename, nFullPathname, zFullPathname);
-      mutexShared = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-      sqlite3_mutex_enter(mutexShared);
-      for(pBt=sqlite3SharedCacheList; pBt; pBt=pBt->pNext){
-        assert( pBt->nRef>0 );
-        if( 0==strcmp(zFullPathname, sqlite3PagerFilename(pBt->pPager))
-                 && sqlite3PagerVfs(pBt->pPager)==pVfs ){
-          p->pBt = pBt;
-          pBt->nRef++;
-          break;
-        }
-      }
-      sqlite3_mutex_leave(mutexShared);
-      sqlite3_free(zFullPathname);
-    }
-#ifdef SQLITE_DEBUG
-    else{
-      /* In debug mode, we mark all persistent databases as sharable
-      ** even when they are not.  This exercises the locking code and
-      ** gives more opportunity for asserts(sqlite3_mutex_held())
-      ** statements to find locking problems.
-      */
-      p->sharable = 1;
-    }
-#endif
-  }
-#endif
-  if( pBt==0 ){
-    /*
-    ** The following asserts make sure that structures used by the btree are
-    ** the right size.  This is to guard against size changes that result
-    ** when compiling on a different architecture.
+  if( nSavepoint>nCurrent && pPager->useJournal ){
+    int ii;                                 /* Iterator variable */
+    PagerSavepoint *aNew;                   /* New Pager.aSavepoint array */
+
+    /* Either there is no active journal or the sub-journal is open or 
+    ** the journal is always stored in memory */
+    assert( pPager->nSavepoint==0 || isOpen(pPager->sjfd) ||
+            pPager->journalMode==PAGER_JOURNALMODE_MEMORY );
+
+    /* Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM
+    ** if the allocation fails. Otherwise, zero the new portion in case a 
+    ** malloc failure occurs while populating it in the for(...) loop below.
     */
-    assert( sizeof(i64)==8 || sizeof(i64)==4 );
-    assert( sizeof(u64)==8 || sizeof(u64)==4 );
-    assert( sizeof(u32)==4 );
-    assert( sizeof(u16)==2 );
-    assert( sizeof(Pgno)==4 );
-  
-    pBt = sqlite3MallocZero( sizeof(*pBt) );
-    if( pBt==0 ){
-      rc = SQLITE_NOMEM;
-      goto btree_open_out;
-    }
-    pBt->busyHdr.xFunc = sqlite3BtreeInvokeBusyHandler;
-    pBt->busyHdr.pArg = pBt;
-    rc = sqlite3PagerOpen(pVfs, &pBt->pPager, zFilename,
-                          EXTRA_SIZE, flags, vfsFlags);
-    if( rc==SQLITE_OK ){
-      rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
-    }
-    if( rc!=SQLITE_OK ){
-      goto btree_open_out;
+    aNew = (PagerSavepoint *)sqlite3Realloc(
+        pPager->aSavepoint, sizeof(PagerSavepoint)*nSavepoint
+    );
+    if( !aNew ){
+      return SQLITE_NOMEM;
     }
-    sqlite3PagerSetBusyhandler(pBt->pPager, &pBt->busyHdr);
-    p->pBt = pBt;
-  
-    sqlite3PagerSetDestructor(pBt->pPager, pageDestructor);
-    sqlite3PagerSetReiniter(pBt->pPager, pageReinit);
-    pBt->pCursor = 0;
-    pBt->pPage1 = 0;
-    pBt->readOnly = sqlite3PagerIsreadonly(pBt->pPager);
-    pBt->pageSize = get2byte(&zDbHeader[16]);
-    if( pBt->pageSize<512 || pBt->pageSize>SQLITE_MAX_PAGE_SIZE
-         || ((pBt->pageSize-1)&pBt->pageSize)!=0 ){
-      pBt->pageSize = 0;
-      sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
-      pBt->maxEmbedFrac = 64;   /* 25% */
-      pBt->minEmbedFrac = 32;   /* 12.5% */
-      pBt->minLeafFrac = 32;    /* 12.5% */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      /* If the magic name ":memory:" will create an in-memory database, then
-      ** leave the autoVacuum mode at 0 (do not auto-vacuum), even if
-      ** SQLITE_DEFAULT_AUTOVACUUM is true. On the other hand, if
-      ** SQLITE_OMIT_MEMORYDB has been defined, then ":memory:" is just a
-      ** regular file-name. In this case the auto-vacuum applies as per normal.
-      */
-      if( zFilename && !isMemdb ){
-        pBt->autoVacuum = (SQLITE_DEFAULT_AUTOVACUUM ? 1 : 0);
-        pBt->incrVacuum = (SQLITE_DEFAULT_AUTOVACUUM==2 ? 1 : 0);
+    memset(&aNew[nCurrent], 0, (nSavepoint-nCurrent) * sizeof(PagerSavepoint));
+    pPager->aSavepoint = aNew;
+    pPager->nSavepoint = nSavepoint;
+
+    /* Populate the PagerSavepoint structures just allocated. */
+    for(ii=nCurrent; ii<nSavepoint; ii++){
+      assert( pPager->dbSizeValid );
+      aNew[ii].nOrig = pPager->dbSize;
+      if( isOpen(pPager->jfd) && ALWAYS(pPager->journalOff>0) ){
+        aNew[ii].iOffset = pPager->journalOff;
+      }else{
+        aNew[ii].iOffset = JOURNAL_HDR_SZ(pPager);
       }
-#endif
-      nReserve = 0;
-    }else{
-      nReserve = zDbHeader[20];
-      pBt->maxEmbedFrac = zDbHeader[21];
-      pBt->minEmbedFrac = zDbHeader[22];
-      pBt->minLeafFrac = zDbHeader[23];
-      pBt->pageSizeFixed = 1;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      pBt->autoVacuum = (get4byte(&zDbHeader[36 + 4*4])?1:0);
-      pBt->incrVacuum = (get4byte(&zDbHeader[36 + 7*4])?1:0);
-#endif
-    }
-    pBt->usableSize = pBt->pageSize - nReserve;
-    assert( (pBt->pageSize & 7)==0 );  /* 8-byte alignment of pageSize */
-    sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
-   
-#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
-    /* Add the new BtShared object to the linked list sharable BtShareds.
-    */
-    if( p->sharable ){
-      sqlite3_mutex *mutexShared;
-      pBt->nRef = 1;
-      mutexShared = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-      if( SQLITE_THREADSAFE ){
-        pBt->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
-        if( pBt->mutex==0 ){
-          rc = SQLITE_NOMEM;
-          db->mallocFailed = 0;
-          goto btree_open_out;
-        }
+      aNew[ii].iSubRec = pPager->nSubRec;
+      aNew[ii].pInSavepoint = sqlite3BitvecCreate(pPager->dbSize);
+      if( !aNew[ii].pInSavepoint ){
+        return SQLITE_NOMEM;
       }
-      sqlite3_mutex_enter(mutexShared);
-      pBt->pNext = sqlite3SharedCacheList;
-      sqlite3SharedCacheList = pBt;
-      sqlite3_mutex_leave(mutexShared);
     }
-#endif
-  }
 
-#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
-  /* If the new Btree uses a sharable pBtShared, then link the new
-  ** Btree into the list of all sharable Btrees for the same connection.
-  ** The list is kept in ascending order by pBt address.
-  */
-  if( p->sharable ){
-    int i;
-    Btree *pSib;
-    for(i=0; i<db->nDb; i++){
-      if( (pSib = db->aDb[i].pBt)!=0 && pSib->sharable ){
-        while( pSib->pPrev ){ pSib = pSib->pPrev; }
-        if( p->pBt<pSib->pBt ){
-          p->pNext = pSib;
-          p->pPrev = 0;
-          pSib->pPrev = p;
-        }else{
-          while( pSib->pNext && pSib->pNext->pBt<p->pBt ){
-            pSib = pSib->pNext;
-          }
-          p->pNext = pSib->pNext;
-          p->pPrev = pSib;
-          if( p->pNext ){
-            p->pNext->pPrev = p;
-          }
-          pSib->pNext = p;
-        }
-        break;
-      }
-    }
+    /* Open the sub-journal, if it is not already opened. */
+    rc = openSubJournal(pPager);
+    assertTruncateConstraint(pPager);
   }
-#endif
-  *ppBtree = p;
 
-btree_open_out:
-  if( rc!=SQLITE_OK ){
-    if( pBt && pBt->pPager ){
-      sqlite3PagerClose(pBt->pPager);
-    }
-    sqlite3_free(pBt);
-    sqlite3_free(p);
-    *ppBtree = 0;
-  }
   return rc;
 }
 
 /*
-** Decrement the BtShared.nRef counter.  When it reaches zero,
-** remove the BtShared structure from the sharing list.  Return
-** true if the BtShared.nRef counter reaches zero and return
-** false if it is still positive.
-*/
-static int removeFromSharingList(BtShared *pBt){
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  sqlite3_mutex *pMaster;
-  BtShared *pList;
-  int removed = 0;
+** This function is called to rollback or release (commit) a savepoint.
+** The savepoint to release or rollback need not be the most recently 
+** created savepoint.
+**
+** Parameter op is always either SAVEPOINT_ROLLBACK or SAVEPOINT_RELEASE.
+** If it is SAVEPOINT_RELEASE, then release and destroy the savepoint with
+** index iSavepoint. If it is SAVEPOINT_ROLLBACK, then rollback all changes
+** that have occurred since the specified savepoint was created.
+**
+** The savepoint to rollback or release is identified by parameter 
+** iSavepoint. A value of 0 means to operate on the outermost savepoint
+** (the first created). A value of (Pager.nSavepoint-1) means operate
+** on the most recently created savepoint. If iSavepoint is greater than
+** (Pager.nSavepoint-1), then this function is a no-op.
+**
+** If a negative value is passed to this function, then the current
+** transaction is rolled back. This is different to calling 
+** sqlite3PagerRollback() because this function does not terminate
+** the transaction or unlock the database, it just restores the 
+** contents of the database to its original state. 
+**
+** In any case, all savepoints with an index greater than iSavepoint 
+** are destroyed. If this is a release operation (op==SAVEPOINT_RELEASE),
+** then savepoint iSavepoint is also destroyed.
+**
+** This function may return SQLITE_NOMEM if a memory allocation fails,
+** or an IO error code if an IO error occurs while rolling back a 
+** savepoint. If no errors occur, SQLITE_OK is returned.
+*/ 
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
+  int rc = SQLITE_OK;
 
-  assert( sqlite3_mutex_notheld(pBt->mutex) );
-  pMaster = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-  sqlite3_mutex_enter(pMaster);
-  pBt->nRef--;
-  if( pBt->nRef<=0 ){
-    if( sqlite3SharedCacheList==pBt ){
-      sqlite3SharedCacheList = pBt->pNext;
-    }else{
-      pList = sqlite3SharedCacheList;
-      while( pList && pList->pNext!=pBt ){
-        pList=pList->pNext;
-      }
-      if( pList ){
-        pList->pNext = pBt->pNext;
-      }
-    }
-    if( SQLITE_THREADSAFE ){
-      sqlite3_mutex_free(pBt->mutex);
-    }
-    removed = 1;
-  }
-  sqlite3_mutex_leave(pMaster);
-  return removed;
-#else
-  return 1;
-#endif
-}
+  assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
+  assert( iSavepoint>=0 || op==SAVEPOINT_ROLLBACK );
 
-/*
-** Close an open database and invalidate all cursors.
-*/
-SQLITE_PRIVATE int sqlite3BtreeClose(Btree *p){
-  BtShared *pBt = p->pBt;
-  BtCursor *pCur;
+  if( iSavepoint<pPager->nSavepoint ){
+    int ii;            /* Iterator variable */
+    int nNew;          /* Number of remaining savepoints after this op. */
 
-  /* Close all cursors opened via this handle.  */
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  pCur = pBt->pCursor;
-  while( pCur ){
-    BtCursor *pTmp = pCur;
-    pCur = pCur->pNext;
-    if( pTmp->pBtree==p ){
-      sqlite3BtreeCloseCursor(pTmp);
+    /* Figure out how many savepoints will still be active after this
+    ** operation. Store this value in nNew. Then free resources associated 
+    ** with any savepoints that are destroyed by this operation.
+    */
+    nNew = iSavepoint + (op==SAVEPOINT_ROLLBACK);
+    for(ii=nNew; ii<pPager->nSavepoint; ii++){
+      sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
     }
-  }
-
-  /* Rollback any active transaction and free the handle structure.
-  ** The call to sqlite3BtreeRollback() drops any table-locks held by
-  ** this handle.
-  */
-  sqlite3BtreeRollback(p);
-  sqlite3BtreeLeave(p);
+    pPager->nSavepoint = nNew;
 
-  /* If there are still other outstanding references to the shared-btree
-  ** structure, return now. The remainder of this procedure cleans 
-  ** up the shared-btree.
-  */
-  assert( p->wantToLock==0 && p->locked==0 );
-  if( !p->sharable || removeFromSharingList(pBt) ){
-    /* The pBt is no longer on the sharing list, so we can access
-    ** it without having to hold the mutex.
-    **
-    ** Clean out and delete the BtShared object.
+    /* If this is a rollback operation, playback the specified savepoint.
+    ** If this is a temp-file, it is possible that the journal file has
+    ** not yet been opened. In this case there have been no changes to
+    ** the database file, so the playback operation can be skipped.
     */
-    assert( !pBt->pCursor );
-    sqlite3PagerClose(pBt->pPager);
-    if( pBt->xFreeSchema && pBt->pSchema ){
-      pBt->xFreeSchema(pBt->pSchema);
+    if( op==SAVEPOINT_ROLLBACK && isOpen(pPager->jfd) ){
+      PagerSavepoint *pSavepoint = (nNew==0)?0:&pPager->aSavepoint[nNew-1];
+      rc = pagerPlaybackSavepoint(pPager, pSavepoint);
+      assert(rc!=SQLITE_DONE);
+    }
+  
+    /* If this is a release of the outermost savepoint, truncate 
+    ** the sub-journal to zero bytes in size. */
+    if( nNew==0 && op==SAVEPOINT_RELEASE && isOpen(pPager->sjfd) ){
+      assert( rc==SQLITE_OK );
+      rc = sqlite3OsTruncate(pPager->sjfd, 0);
+      pPager->nSubRec = 0;
     }
-    sqlite3_free(pBt->pSchema);
-    sqlite3_free(pBt->pTmpSpace);
-    sqlite3_free(pBt);
   }
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  assert( p->wantToLock==0 );
-  assert( p->locked==0 );
-  if( p->pPrev ) p->pPrev->pNext = p->pNext;
-  if( p->pNext ) p->pNext->pPrev = p->pPrev;
-#endif
-
-  sqlite3_free(p);
-  return SQLITE_OK;
+  return rc;
 }
 
 /*
-** Change the limit on the number of pages allowed in the cache.
-**
-** The maximum number of cache pages is set to the absolute
-** value of mxPage.  If mxPage is negative, the pager will
-** operate asynchronously - it will not stop to do fsync()s
-** to insure data is written to the disk surface before
-** continuing.  Transactions still work if synchronous is off,
-** and the database cannot be corrupted if this program
-** crashes.  But if the operating system crashes or there is
-** an abrupt power failure when synchronous is off, the database
-** could be left in an inconsistent and unrecoverable state.
-** Synchronous is on by default so database corruption is not
-** normally a worry.
+** Return the full pathname of the database file.
 */
-SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
-  BtShared *pBt = p->pBt;
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  sqlite3BtreeEnter(p);
-  sqlite3PagerSetCachesize(pBt->pPager, mxPage);
-  sqlite3BtreeLeave(p);
-  return SQLITE_OK;
+SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager *pPager){
+  return pPager->zFilename;
 }
 
 /*
-** Change the way data is synced to disk in order to increase or decrease
-** how well the database resists damage due to OS crashes and power
-** failures.  Level 1 is the same as asynchronous (no syncs() occur and
-** there is a high probability of damage)  Level 2 is the default.  There
-** is a very low but non-zero probability of damage.  Level 3 reduces the
-** probability of damage to near zero but with a write performance reduction.
+** Return the VFS structure for the pager.
 */
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree *p, int level, int fullSync){
-  BtShared *pBt = p->pBt;
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  sqlite3BtreeEnter(p);
-  sqlite3PagerSetSafetyLevel(pBt->pPager, level, fullSync);
-  sqlite3BtreeLeave(p);
-  return SQLITE_OK;
+SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager *pPager){
+  return pPager->pVfs;
 }
-#endif
 
 /*
-** Return TRUE if the given btree is set to safety level 1.  In other
-** words, return TRUE if no sync() occurs on the disk files.
+** Return the file handle for the database file associated
+** with the pager.  This might return NULL if the file has
+** not yet been opened.
 */
-SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree *p){
-  BtShared *pBt = p->pBt;
-  int rc;
-  assert( sqlite3_mutex_held(p->db->mutex) );  
-  sqlite3BtreeEnter(p);
-  assert( pBt && pBt->pPager );
-  rc = sqlite3PagerNosync(pBt->pPager);
-  sqlite3BtreeLeave(p);
-  return rc;
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager *pPager){
+  return pPager->fd;
 }
 
-#if !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM)
 /*
-** Change the default pages size and the number of reserved bytes per page.
-**
-** The page size must be a power of 2 between 512 and 65536.  If the page
-** size supplied does not meet this constraint then the page size is not
-** changed.
-**
-** Page sizes are constrained to be a power of two so that the region
-** of the database file used for locking (beginning at PENDING_BYTE,
-** the first byte past the 1GB boundary, 0x40000000) needs to occur
-** at the beginning of a page.
-**
-** If parameter nReserve is less than zero, then the number of reserved
-** bytes per page is left unchanged.
+** Return the full pathname of the journal file.
 */
-SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int pageSize, int nReserve){
-  int rc = SQLITE_OK;
-  BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  if( pBt->pageSizeFixed ){
-    sqlite3BtreeLeave(p);
-    return SQLITE_READONLY;
-  }
-  if( nReserve<0 ){
-    nReserve = pBt->pageSize - pBt->usableSize;
-  }
-  if( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE &&
-        ((pageSize-1)&pageSize)==0 ){
-    assert( (pageSize & 7)==0 );
-    assert( !pBt->pPage1 && !pBt->pCursor );
-    pBt->pageSize = pageSize;
-    sqlite3_free(pBt->pTmpSpace);
-    pBt->pTmpSpace = 0;
-    rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
-  }
-  pBt->usableSize = pBt->pageSize - nReserve;
-  sqlite3BtreeLeave(p);
-  return rc;
+SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager *pPager){
+  return pPager->zJournal;
 }
 
 /*
-** Return the currently defined page size
+** Return true if fsync() calls are disabled for this pager.  Return FALSE
+** if fsync()s are executed normally.
 */
-SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree *p){
-  return p->pBt->pageSize;
-}
-SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree *p){
-  int n;
-  sqlite3BtreeEnter(p);
-  n = p->pBt->pageSize - p->pBt->usableSize;
-  sqlite3BtreeLeave(p);
-  return n;
+SQLITE_PRIVATE int sqlite3PagerNosync(Pager *pPager){
+  return pPager->noSync;
 }
 
+#ifdef SQLITE_HAS_CODEC
 /*
-** Set the maximum page count for a database if mxPage is positive.
-** No changes are made if mxPage is 0 or negative.
-** Regardless of the value of mxPage, return the maximum page count.
+** Set or retrieve the codec for this pager
 */
-SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree *p, int mxPage){
-  int n;
-  sqlite3BtreeEnter(p);
-  n = sqlite3PagerMaxPageCount(p->pBt->pPager, mxPage);
-  sqlite3BtreeLeave(p);
-  return n;
+static void sqlite3PagerSetCodec(
+  Pager *pPager,
+  void *(*xCodec)(void*,void*,Pgno,int),
+  void (*xCodecSizeChng)(void*,int,int),
+  void (*xCodecFree)(void*),
+  void *pCodec
+){
+  if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+  pPager->xCodec = xCodec;
+  pPager->xCodecSizeChng = xCodecSizeChng;
+  pPager->xCodecFree = xCodecFree;
+  pPager->pCodec = pCodec;
+  pagerReportSize(pPager);
 }
-#endif /* !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM) */
+static void *sqlite3PagerGetCodec(Pager *pPager){
+  return pPager->pCodec;
+}
+#endif
 
+#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Change the 'auto-vacuum' property of the database. If the 'autoVacuum'
-** parameter is non-zero, then auto-vacuum mode is enabled. If zero, it
-** is disabled. The default value for the auto-vacuum property is 
-** determined by the SQLITE_DEFAULT_AUTOVACUUM macro.
+** Move the page pPg to location pgno in the file.
+**
+** There must be no references to the page previously located at
+** pgno (which we call pPgOld) though that page is allowed to be
+** in cache.  If the page previously located at pgno is not already
+** in the rollback journal, it is not put there by by this routine.
+**
+** References to the page pPg remain valid. Updating any
+** meta-data associated with pPg (i.e. data stored in the nExtra bytes
+** allocated along with the page) is the responsibility of the caller.
+**
+** A transaction must be active when this routine is called. It used to be
+** required that a statement transaction was not active, but this restriction
+** has been removed (CREATE INDEX needs to move a page when a statement
+** transaction is active).
+**
+** If the fourth argument, isCommit, is non-zero, then this page is being
+** moved as part of a database reorganization just before the transaction 
+** is being committed. In this case, it is guaranteed that the database page 
+** pPg refers to will not be written to again within this transaction.
+**
+** This function may return SQLITE_NOMEM or an IO error code if an error
+** occurs. Otherwise, it returns SQLITE_OK.
 */
-SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *p, int autoVacuum){
-#ifdef SQLITE_OMIT_AUTOVACUUM
-  return SQLITE_READONLY;
-#else
-  BtShared *pBt = p->pBt;
-  int rc = SQLITE_OK;
-  int av = (autoVacuum?1:0);
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
+  PgHdr *pPgOld;               /* The page being overwritten. */
+  Pgno needSyncPgno = 0;       /* Old value of pPg->pgno, if sync is required */
+  int rc;                      /* Return code */
+  Pgno origPgno;               /* The original page number */
 
-  sqlite3BtreeEnter(p);
-  if( pBt->pageSizeFixed && av!=pBt->autoVacuum ){
-    rc = SQLITE_READONLY;
-  }else{
-    pBt->autoVacuum = av;
+  assert( pPg->nRef>0 );
+
+  /* If the page being moved is dirty and has not been saved by the latest
+  ** savepoint, then save the current contents of the page into the 
+  ** sub-journal now. This is required to handle the following scenario:
+  **
+  **   BEGIN;
+  **     <journal page X, then modify it in memory>
+  **     SAVEPOINT one;
+  **       <Move page X to location Y>
+  **     ROLLBACK TO one;
+  **
+  ** If page X were not written to the sub-journal here, it would not
+  ** be possible to restore its contents when the "ROLLBACK TO one"
+  ** statement were is processed.
+  **
+  ** subjournalPage() may need to allocate space to store pPg->pgno into
+  ** one or more savepoint bitvecs. This is the reason this function
+  ** may return SQLITE_NOMEM.
+  */
+  if( pPg->flags&PGHDR_DIRTY 
+   && subjRequiresPage(pPg)
+   && SQLITE_OK!=(rc = subjournalPage(pPg))
+  ){
+    return rc;
   }
-  sqlite3BtreeLeave(p);
-  return rc;
-#endif
-}
 
-/*
-** Return the value of the 'auto-vacuum' property. If auto-vacuum is 
-** enabled 1 is returned. Otherwise 0.
-*/
-SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *p){
-#ifdef SQLITE_OMIT_AUTOVACUUM
-  return BTREE_AUTOVACUUM_NONE;
-#else
-  int rc;
-  sqlite3BtreeEnter(p);
-  rc = (
-    (!p->pBt->autoVacuum)?BTREE_AUTOVACUUM_NONE:
-    (!p->pBt->incrVacuum)?BTREE_AUTOVACUUM_FULL:
-    BTREE_AUTOVACUUM_INCR
-  );
-  sqlite3BtreeLeave(p);
-  return rc;
-#endif
-}
+  PAGERTRACE(("MOVE %d page %d (needSync=%d) moves to %d\n", 
+      PAGERID(pPager), pPg->pgno, (pPg->flags&PGHDR_NEED_SYNC)?1:0, pgno));
+  IOTRACE(("MOVE %p %d %d\n", pPager, pPg->pgno, pgno))
 
+  /* If the journal needs to be sync()ed before page pPg->pgno can
+  ** be written to, store pPg->pgno in local variable needSyncPgno.
+  **
+  ** If the isCommit flag is set, there is no need to remember that
+  ** the journal needs to be sync()ed before database page pPg->pgno 
+  ** can be written to. The caller has already promised not to write to it.
+  */
+  if( (pPg->flags&PGHDR_NEED_SYNC) && !isCommit ){
+    needSyncPgno = pPg->pgno;
+    assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
+    assert( pPg->flags&PGHDR_DIRTY );
+    assert( pPager->needSync );
+  }
 
-/*
-** Get a reference to pPage1 of the database file.  This will
-** also acquire a readlock on that file.
-**
-** SQLITE_OK is returned on success.  If the file is not a
-** well-formed database file, then SQLITE_CORRUPT is returned.
-** SQLITE_BUSY is returned if the database is locked.  SQLITE_NOMEM
-** is returned if we run out of memory. 
-*/
-static int lockBtree(BtShared *pBt){
-  int rc;
-  MemPage *pPage1;
-  int nPage;
+  /* If the cache contains a page with page-number pgno, remove it
+  ** from its hash chain. Also, if the PgHdr.needSync was set for 
+  ** page pgno before the 'move' operation, it needs to be retained 
+  ** for the page moved there.
+  */
+  pPg->flags &= ~PGHDR_NEED_SYNC;
+  pPgOld = pager_lookup(pPager, pgno);
+  assert( !pPgOld || pPgOld->nRef==1 );
+  if( pPgOld ){
+    pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
+    sqlite3PcacheDrop(pPgOld);
+  }
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  if( pBt->pPage1 ) return SQLITE_OK;
-  rc = sqlite3BtreeGetPage(pBt, 1, &pPage1, 0);
-  if( rc!=SQLITE_OK ) return rc;
+  origPgno = pPg->pgno;
+  sqlite3PcacheMove(pPg, pgno);
+  sqlite3PcacheMakeDirty(pPg);
+  pPager->dbModified = 1;
 
-  /* Do some checking to help insure the file we opened really is
-  ** a valid database file. 
-  */
-  rc = SQLITE_NOTADB;
-  nPage = sqlite3PagerPagecount(pBt->pPager);
-  if( nPage<0 ){
-    rc = SQLITE_IOERR;
-    goto page1_init_failed;
-  }else if( nPage>0 ){
-    int pageSize;
-    int usableSize;
-    u8 *page1 = pPage1->aData;
-    if( memcmp(page1, zMagicHeader, 16)!=0 ){
-      goto page1_init_failed;
-    }
-    if( page1[18]>1 ){
-      pBt->readOnly = 1;
-    }
-    if( page1[19]>1 ){
-      goto page1_init_failed;
-    }
-    pageSize = get2byte(&page1[16]);
-    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
-        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
-    ){
-      goto page1_init_failed;
-    }
-    assert( (pageSize & 7)==0 );
-    usableSize = pageSize - page1[20];
-    if( pageSize!=pBt->pageSize ){
-      /* After reading the first page of the database assuming a page size
-      ** of BtShared.pageSize, we have discovered that the page-size is
-      ** actually pageSize. Unlock the database, leave pBt->pPage1 at
-      ** zero and return SQLITE_OK. The caller will call this function
-      ** again with the correct page-size.
-      */
-      releasePage(pPage1);
-      pBt->usableSize = usableSize;
-      pBt->pageSize = pageSize;
-      sqlite3_free(pBt->pTmpSpace);
-      pBt->pTmpSpace = 0;
-      sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
-      return SQLITE_OK;
-    }
-    if( usableSize<500 ){
-      goto page1_init_failed;
+  if( needSyncPgno ){
+    /* If needSyncPgno is non-zero, then the journal file needs to be 
+    ** sync()ed before any data is written to database file page needSyncPgno.
+    ** Currently, no such page exists in the page-cache and the 
+    ** "is journaled" bitvec flag has been set. This needs to be remedied by
+    ** loading the page into the pager-cache and setting the PgHdr.needSync 
+    ** flag.
+    **
+    ** If the attempt to load the page into the page-cache fails, (due
+    ** to a malloc() or IO failure), clear the bit in the pInJournal[]
+    ** array. Otherwise, if the page is loaded and written again in
+    ** this transaction, it may be written to the database file before
+    ** it is synced into the journal file. This way, it may end up in
+    ** the journal file twice, but that is not a problem.
+    **
+    ** The sqlite3PagerGet() call may cause the journal to sync. So make
+    ** sure the Pager.needSync flag is set too.
+    */
+    PgHdr *pPgHdr;
+    assert( pPager->needSync );
+    rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
+    if( rc!=SQLITE_OK ){
+      if( needSyncPgno<=pPager->dbOrigSize ){
+        assert( pPager->pTmpSpace!=0 );
+        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno, pPager->pTmpSpace);
+      }
+      return rc;
     }
-    pBt->pageSize = pageSize;
-    pBt->usableSize = usableSize;
-    pBt->maxEmbedFrac = page1[21];
-    pBt->minEmbedFrac = page1[22];
-    pBt->minLeafFrac = page1[23];
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
-    pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
-#endif
+    pPager->needSync = 1;
+    assert( pPager->noSync==0 && !MEMDB );
+    pPgHdr->flags |= PGHDR_NEED_SYNC;
+    sqlite3PcacheMakeDirty(pPgHdr);
+    sqlite3PagerUnref(pPgHdr);
   }
 
-  /* maxLocal is the maximum amount of payload to store locally for
-  ** a cell.  Make sure it is small enough so that at least minFanout
-  ** cells can will fit on one page.  We assume a 10-byte page header.
-  ** Besides the payload, the cell must store:
-  **     2-byte pointer to the cell
-  **     4-byte child pointer
-  **     9-byte nKey value
-  **     4-byte nData value
-  **     4-byte overflow page pointer
-  ** So a cell consists of a 2-byte poiner, a header which is as much as
-  ** 17 bytes long, 0 to N bytes of payload, and an optional 4 byte overflow
-  ** page pointer.
+  /*
+  ** For an in-memory database, make sure the original page continues
+  ** to exist, in case the transaction needs to roll back.  We allocate
+  ** the page now, instead of at rollback, because we can better deal
+  ** with an out-of-memory error now.  Ticket #3761.
   */
-  pBt->maxLocal = (pBt->usableSize-12)*pBt->maxEmbedFrac/255 - 23;
-  pBt->minLocal = (pBt->usableSize-12)*pBt->minEmbedFrac/255 - 23;
-  pBt->maxLeaf = pBt->usableSize - 35;
-  pBt->minLeaf = (pBt->usableSize-12)*pBt->minLeafFrac/255 - 23;
-  if( pBt->minLocal>pBt->maxLocal || pBt->maxLocal<0 ){
-    goto page1_init_failed;
+  if( MEMDB ){
+    DbPage *pNew;
+    rc = sqlite3PagerAcquire(pPager, origPgno, &pNew, 1);
+    if( rc!=SQLITE_OK ){
+      sqlite3PcacheMove(pPg, origPgno);
+      return rc;
+    }
+    sqlite3PagerUnref(pNew);
   }
-  assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
-  pBt->pPage1 = pPage1;
-  return SQLITE_OK;
 
-page1_init_failed:
-  releasePage(pPage1);
-  pBt->pPage1 = 0;
-  return rc;
+  return SQLITE_OK;
 }
+#endif
 
 /*
-** This routine works like lockBtree() except that it also invokes the
-** busy callback if there is lock contention.
+** Return a pointer to the data for the specified page.
 */
-static int lockBtreeWithRetry(Btree *pRef){
-  int rc = SQLITE_OK;
-
-  assert( sqlite3BtreeHoldsMutex(pRef) );
-  if( pRef->inTrans==TRANS_NONE ){
-    u8 inTransaction = pRef->pBt->inTransaction;
-    btreeIntegrity(pRef);
-    rc = sqlite3BtreeBeginTrans(pRef, 0);
-    pRef->pBt->inTransaction = inTransaction;
-    pRef->inTrans = TRANS_NONE;
-    if( rc==SQLITE_OK ){
-      pRef->pBt->nTransaction--;
-    }
-    btreeIntegrity(pRef);
-  }
-  return rc;
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *pPg){
+  assert( pPg->nRef>0 || pPg->pPager->memDb );
+  return pPg->pData;
 }
-       
 
 /*
-** If there are no outstanding cursors and we are not in the middle
-** of a transaction but there is a read lock on the database, then
-** this routine unrefs the first page of the database file which 
-** has the effect of releasing the read lock.
-**
-** If there are any outstanding cursors, this routine is a no-op.
-**
-** If there is a transaction in progress, this routine is a no-op.
+** Return a pointer to the Pager.nExtra bytes of "extra" space 
+** allocated along with the specified page.
 */
-static void unlockBtreeIfUnused(BtShared *pBt){
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  if( pBt->inTransaction==TRANS_NONE && pBt->pCursor==0 && pBt->pPage1!=0 ){
-    if( sqlite3PagerRefcount(pBt->pPager)>=1 ){
-      assert( pBt->pPage1->aData );
-#if 0
-      if( pBt->pPage1->aData==0 ){
-        MemPage *pPage = pBt->pPage1;
-        pPage->aData = sqlite3PagerGetData(pPage->pDbPage);
-        pPage->pBt = pBt;
-        pPage->pgno = 1;
-      }
-#endif
-      releasePage(pBt->pPage1);
-    }
-    pBt->pPage1 = 0;
-    pBt->inStmt = 0;
-  }
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *pPg){
+  return pPg->pExtra;
 }
 
 /*
-** Create a new database by initializing the first page of the
-** file.
+** Get/set the locking-mode for this pager. Parameter eMode must be one
+** of PAGER_LOCKINGMODE_QUERY, PAGER_LOCKINGMODE_NORMAL or 
+** PAGER_LOCKINGMODE_EXCLUSIVE. If the parameter is not _QUERY, then
+** the locking-mode is set to the value specified.
+**
+** The returned value is either PAGER_LOCKINGMODE_NORMAL or
+** PAGER_LOCKINGMODE_EXCLUSIVE, indicating the current (possibly updated)
+** locking-mode.
 */
-static int newDatabase(BtShared *pBt){
-  MemPage *pP1;
-  unsigned char *data;
-  int rc;
-
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  if( sqlite3PagerPagecount(pBt->pPager)>0 ) return SQLITE_OK;
-  pP1 = pBt->pPage1;
-  assert( pP1!=0 );
-  data = pP1->aData;
-  rc = sqlite3PagerWrite(pP1->pDbPage);
-  if( rc ) return rc;
-  memcpy(data, zMagicHeader, sizeof(zMagicHeader));
-  assert( sizeof(zMagicHeader)==16 );
-  put2byte(&data[16], pBt->pageSize);
-  data[18] = 1;
-  data[19] = 1;
-  data[20] = pBt->pageSize - pBt->usableSize;
-  data[21] = pBt->maxEmbedFrac;
-  data[22] = pBt->minEmbedFrac;
-  data[23] = pBt->minLeafFrac;
-  memset(&data[24], 0, 100-24);
-  zeroPage(pP1, PTF_INTKEY|PTF_LEAF|PTF_LEAFDATA );
-  pBt->pageSizeFixed = 1;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  assert( pBt->autoVacuum==1 || pBt->autoVacuum==0 );
-  assert( pBt->incrVacuum==1 || pBt->incrVacuum==0 );
-  put4byte(&data[36 + 4*4], pBt->autoVacuum);
-  put4byte(&data[36 + 7*4], pBt->incrVacuum);
-#endif
-  return SQLITE_OK;
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *pPager, int eMode){
+  assert( eMode==PAGER_LOCKINGMODE_QUERY
+            || eMode==PAGER_LOCKINGMODE_NORMAL
+            || eMode==PAGER_LOCKINGMODE_EXCLUSIVE );
+  assert( PAGER_LOCKINGMODE_QUERY<0 );
+  assert( PAGER_LOCKINGMODE_NORMAL>=0 && PAGER_LOCKINGMODE_EXCLUSIVE>=0 );
+  if( eMode>=0 && !pPager->tempFile ){
+    pPager->exclusiveMode = (u8)eMode;
+  }
+  return (int)pPager->exclusiveMode;
 }
 
 /*
-** Attempt to start a new transaction. A write-transaction
-** is started if the second argument is nonzero, otherwise a read-
-** transaction.  If the second argument is 2 or more and exclusive
-** transaction is started, meaning that no other process is allowed
-** to access the database.  A preexisting transaction may not be
-** upgraded to exclusive by calling this routine a second time - the
-** exclusivity flag only works for a new transaction.
+** Get/set the journal-mode for this pager. Parameter eMode must be one of:
 **
-** A write-transaction must be started before attempting any 
-** changes to the database.  None of the following routines 
-** will work unless a transaction is started first:
+**    PAGER_JOURNALMODE_QUERY
+**    PAGER_JOURNALMODE_DELETE
+**    PAGER_JOURNALMODE_TRUNCATE
+**    PAGER_JOURNALMODE_PERSIST
+**    PAGER_JOURNALMODE_OFF
+**    PAGER_JOURNALMODE_MEMORY
 **
-**      sqlite3BtreeCreateTable()
-**      sqlite3BtreeCreateIndex()
-**      sqlite3BtreeClearTable()
-**      sqlite3BtreeDropTable()
-**      sqlite3BtreeInsert()
-**      sqlite3BtreeDelete()
-**      sqlite3BtreeUpdateMeta()
+** If the parameter is not _QUERY, then the journal_mode is set to the
+** value specified if the change is allowed.  The change is disallowed
+** for the following reasons:
 **
-** If an initial attempt to acquire the lock fails because of lock contention
-** and the database was previously unlocked, then invoke the busy handler
-** if there is one.  But if there was previously a read-lock, do not
-** invoke the busy handler - just return SQLITE_BUSY.  SQLITE_BUSY is 
-** returned when there is already a read-lock in order to avoid a deadlock.
+**   *  An in-memory database can only have its journal_mode set to _OFF
+**      or _MEMORY.
 **
-** Suppose there are two processes A and B.  A has a read lock and B has
-** a reserved lock.  B tries to promote to exclusive but is blocked because
-** of A's read lock.  A tries to promote to reserved but is blocked by B.
-** One or the other of the two processes must give way or there can be
-** no progress.  By returning SQLITE_BUSY and not invoking the busy callback
-** when A already has a read lock, we encourage A to give up and let B
-** proceed.
+**   *  The journal mode may not be changed while a transaction is active.
+**
+** The returned indicate the current (possibly updated) journal-mode.
 */
-SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
-  BtShared *pBt = p->pBt;
-  int rc = SQLITE_OK;
-
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  btreeIntegrity(p);
-
-  /* If the btree is already in a write-transaction, or it
-  ** is already in a read-transaction and a read-transaction
-  ** is requested, this is a no-op.
-  */
-  if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
-    goto trans_begun;
-  }
-
-  /* Write transactions are not possible on a read-only database */
-  if( pBt->readOnly && wrflag ){
-    rc = SQLITE_READONLY;
-    goto trans_begun;
-  }
-
-  /* If another database handle has already opened a write transaction 
-  ** on this shared-btree structure and a second write transaction is
-  ** requested, return SQLITE_BUSY.
-  */
-  if( pBt->inTransaction==TRANS_WRITE && wrflag ){
-    rc = SQLITE_BUSY;
-    goto trans_begun;
-  }
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  if( wrflag>1 ){
-    BtLock *pIter;
-    for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
-      if( pIter->pBtree!=p ){
-        rc = SQLITE_BUSY;
-        goto trans_begun;
-      }
-    }
-  }
-#endif
-
-  do {
-    if( pBt->pPage1==0 ){
-      do{
-        rc = lockBtree(pBt);
-      }while( pBt->pPage1==0 && rc==SQLITE_OK );
-    }
-
-    if( rc==SQLITE_OK && wrflag ){
-      if( pBt->readOnly ){
-        rc = SQLITE_READONLY;
-      }else{
-        rc = sqlite3PagerBegin(pBt->pPage1->pDbPage, wrflag>1);
-        if( rc==SQLITE_OK ){
-          rc = newDatabase(pBt);
-        }
-      }
-    }
-  
-    if( rc==SQLITE_OK ){
-      if( wrflag ) pBt->inStmt = 0;
-    }else{
-      unlockBtreeIfUnused(pBt);
-    }
-  }while( rc==SQLITE_BUSY && pBt->inTransaction==TRANS_NONE &&
-          sqlite3BtreeInvokeBusyHandler(pBt, 0) );
-
-  if( rc==SQLITE_OK ){
-    if( p->inTrans==TRANS_NONE ){
-      pBt->nTransaction++;
-    }
-    p->inTrans = (wrflag?TRANS_WRITE:TRANS_READ);
-    if( p->inTrans>pBt->inTransaction ){
-      pBt->inTransaction = p->inTrans;
-    }
-#ifndef SQLITE_OMIT_SHARED_CACHE
-    if( wrflag>1 ){
-      assert( !pBt->pExclusive );
-      pBt->pExclusive = p;
+SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *pPager, int eMode){
+  assert( eMode==PAGER_JOURNALMODE_QUERY
+            || eMode==PAGER_JOURNALMODE_DELETE
+            || eMode==PAGER_JOURNALMODE_TRUNCATE
+            || eMode==PAGER_JOURNALMODE_PERSIST
+            || eMode==PAGER_JOURNALMODE_OFF 
+            || eMode==PAGER_JOURNALMODE_MEMORY );
+  assert( PAGER_JOURNALMODE_QUERY<0 );
+  if( eMode>=0
+   && (!MEMDB || eMode==PAGER_JOURNALMODE_MEMORY 
+              || eMode==PAGER_JOURNALMODE_OFF)
+   && !pPager->dbModified
+   && (!isOpen(pPager->jfd) || 0==pPager->journalOff)
+  ){
+    if( isOpen(pPager->jfd) ){
+      sqlite3OsClose(pPager->jfd);
     }
-#endif
+    pPager->journalMode = (u8)eMode;
   }
-
-
-trans_begun:
-  btreeIntegrity(p);
-  sqlite3BtreeLeave(p);
-  return rc;
+  return (int)pPager->journalMode;
 }
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-
 /*
-** Set the pointer-map entries for all children of page pPage. Also, if
-** pPage contains cells that point to overflow pages, set the pointer
-** map entries for the overflow pages as well.
+** Get/set the size-limit used for persistent journal files.
+**
+** Setting the size limit to -1 means no limit is enforced.
+** An attempt to set a limit smaller than -1 is a no-op.
 */
-static int setChildPtrmaps(MemPage *pPage){
-  int i;                             /* Counter variable */
-  int nCell;                         /* Number of cells in page pPage */
-  int rc;                            /* Return code */
-  BtShared *pBt = pPage->pBt;
-  int isInitOrig = pPage->isInit;
-  Pgno pgno = pPage->pgno;
-
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  rc = sqlite3BtreeInitPage(pPage, pPage->pParent);
-  if( rc!=SQLITE_OK ){
-    goto set_child_ptrmaps_out;
-  }
-  nCell = pPage->nCell;
-
-  for(i=0; i<nCell; i++){
-    u8 *pCell = findCell(pPage, i);
-
-    rc = ptrmapPutOvflPtr(pPage, pCell);
-    if( rc!=SQLITE_OK ){
-      goto set_child_ptrmaps_out;
-    }
-
-    if( !pPage->leaf ){
-      Pgno childPgno = get4byte(pCell);
-      rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
-      if( rc!=SQLITE_OK ) goto set_child_ptrmaps_out;
-    }
-  }
-
-  if( !pPage->leaf ){
-    Pgno childPgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
-    rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *pPager, i64 iLimit){
+  if( iLimit>=-1 ){
+    pPager->journalSizeLimit = iLimit;
   }
+  return pPager->journalSizeLimit;
+}
 
-set_child_ptrmaps_out:
-  pPage->isInit = isInitOrig;
-  return rc;
+/*
+** Return a pointer to the pPager->pBackup variable. The backup module
+** in backup.c maintains the content of this variable. This module
+** uses it opaquely as an argument to sqlite3BackupRestart() and
+** sqlite3BackupUpdate() only.
+*/
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager *pPager){
+  return &pPager->pBackup;
 }
 
+#endif /* SQLITE_OMIT_DISKIO */
+
+/************** End of pager.c ***********************************************/
+/************** Begin file btmutex.c *****************************************/
 /*
-** Somewhere on pPage, which is guarenteed to be a btree page, not an overflow
-** page, is a pointer to page iFrom. Modify this pointer so that it points to
-** iTo. Parameter eType describes the type of pointer to be modified, as 
-** follows:
+** 2007 August 27
 **
-** PTRMAP_BTREE:     pPage is a btree-page. The pointer points at a child 
-**                   page of pPage.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** PTRMAP_OVERFLOW1: pPage is a btree-page. The pointer points at an overflow
-**                   page pointed to by one of the cells on pPage.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** PTRMAP_OVERFLOW2: pPage is an overflow-page. The pointer points at the next
-**                   overflow page in the list.
+*************************************************************************
+**
+** $Id: btmutex.c,v 1.17 2009/07/20 12:33:33 drh Exp $
+**
+** This file contains code used to implement mutexes on Btree objects.
+** This code really belongs in btree.c.  But btree.c is getting too
+** big and we want to break it down some.  This packaged seemed like
+** a good breakout.
+*/
+/************** Include btreeInt.h in the middle of btmutex.c ****************/
+/************** Begin file btreeInt.h ****************************************/
+/*
+** 2004 April 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** $Id: btreeInt.h,v 1.52 2009/07/15 17:25:46 drh Exp $
+**
+** This file implements a external (disk-based) database using BTrees.
+** For a detailed discussion of BTrees, refer to
+**
+**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
+**     "Sorting And Searching", pages 473-480. Addison-Wesley
+**     Publishing Company, Reading, Massachusetts.
+**
+** The basic idea is that each page of the file contains N database
+** entries and N+1 pointers to subpages.
+**
+**   ----------------------------------------------------------------
+**   |  Ptr(0) | Key(0) | Ptr(1) | Key(1) | ... | Key(N-1) | Ptr(N) |
+**   ----------------------------------------------------------------
+**
+** All of the keys on the page that Ptr(0) points to have values less
+** than Key(0).  All of the keys on page Ptr(1) and its subpages have
+** values greater than Key(0) and less than Key(1).  All of the keys
+** on Ptr(N) and its subpages have values greater than Key(N-1).  And
+** so forth.
+**
+** Finding a particular key requires reading O(log(M)) pages from the 
+** disk where M is the number of entries in the tree.
+**
+** In this implementation, a single file can hold one or more separate 
+** BTrees.  Each BTree is identified by the index of its root page.  The
+** key and data for any entry are combined to form the "payload".  A
+** fixed amount of payload can be carried directly on the database
+** page.  If the payload is larger than the preset amount then surplus
+** bytes are stored on overflow pages.  The payload for an entry
+** and the preceding pointer are combined to form a "Cell".  Each 
+** page has a small header which contains the Ptr(N) pointer and other
+** information such as the size of key and data.
+**
+** FORMAT DETAILS
+**
+** The file is divided into pages.  The first page is called page 1,
+** the second is page 2, and so forth.  A page number of zero indicates
+** "no such page".  The page size can be anything between 512 and 65536.
+** Each page can be either a btree page, a freelist page or an overflow
+** page.
+**
+** The first page is always a btree page.  The first 100 bytes of the first
+** page contain a special header (the "file header") that describes the file.
+** The format of the file header is as follows:
+**
+**   OFFSET   SIZE    DESCRIPTION
+**      0      16     Header string: "SQLite format 3\000"
+**     16       2     Page size in bytes.  
+**     18       1     File format write version
+**     19       1     File format read version
+**     20       1     Bytes of unused space at the end of each page
+**     21       1     Max embedded payload fraction
+**     22       1     Min embedded payload fraction
+**     23       1     Min leaf payload fraction
+**     24       4     File change counter
+**     28       4     Reserved for future use
+**     32       4     First freelist page
+**     36       4     Number of freelist pages in the file
+**     40      60     15 4-byte meta values passed to higher layers
+**
+**     40       4     Schema cookie
+**     44       4     File format of schema layer
+**     48       4     Size of page cache
+**     52       4     Largest root-page (auto/incr_vacuum)
+**     56       4     1=UTF-8 2=UTF16le 3=UTF16be
+**     60       4     User version
+**     64       4     Incremental vacuum mode
+**     68       4     unused
+**     72       4     unused
+**     76       4     unused
+**
+** All of the integer values are big-endian (most significant byte first).
+**
+** The file change counter is incremented when the database is changed
+** This counter allows other processes to know when the file has changed
+** and thus when they need to flush their cache.
+**
+** The max embedded payload fraction is the amount of the total usable
+** space in a page that can be consumed by a single cell for standard
+** B-tree (non-LEAFDATA) tables.  A value of 255 means 100%.  The default
+** is to limit the maximum cell size so that at least 4 cells will fit
+** on one page.  Thus the default max embedded payload fraction is 64.
+**
+** If the payload for a cell is larger than the max payload, then extra
+** payload is spilled to overflow pages.  Once an overflow page is allocated,
+** as many bytes as possible are moved into the overflow pages without letting
+** the cell size drop below the min embedded payload fraction.
+**
+** The min leaf payload fraction is like the min embedded payload fraction
+** except that it applies to leaf nodes in a LEAFDATA tree.  The maximum
+** payload fraction for a LEAFDATA tree is always 100% (or 255) and it
+** not specified in the header.
+**
+** Each btree pages is divided into three sections:  The header, the
+** cell pointer array, and the cell content area.  Page 1 also has a 100-byte
+** file header that occurs before the page header.
+**
+**      |----------------|
+**      | file header    |   100 bytes.  Page 1 only.
+**      |----------------|
+**      | page header    |   8 bytes for leaves.  12 bytes for interior nodes
+**      |----------------|
+**      | cell pointer   |   |  2 bytes per cell.  Sorted order.
+**      | array          |   |  Grows downward
+**      |                |   v
+**      |----------------|
+**      | unallocated    |
+**      | space          |
+**      |----------------|   ^  Grows upwards
+**      | cell content   |   |  Arbitrary order interspersed with freeblocks.
+**      | area           |   |  and free space fragments.
+**      |----------------|
+**
+** The page headers looks like this:
+**
+**   OFFSET   SIZE     DESCRIPTION
+**      0       1      Flags. 1: intkey, 2: zerodata, 4: leafdata, 8: leaf
+**      1       2      byte offset to the first freeblock
+**      3       2      number of cells on this page
+**      5       2      first byte of the cell content area
+**      7       1      number of fragmented free bytes
+**      8       4      Right child (the Ptr(N) value).  Omitted on leaves.
+**
+** The flags define the format of this btree page.  The leaf flag means that
+** this page has no children.  The zerodata flag means that this page carries
+** only keys and no data.  The intkey flag means that the key is a integer
+** which is stored in the key size entry of the cell header rather than in
+** the payload area.
+**
+** The cell pointer array begins on the first byte after the page header.
+** The cell pointer array contains zero or more 2-byte numbers which are
+** offsets from the beginning of the page to the cell content in the cell
+** content area.  The cell pointers occur in sorted order.  The system strives
+** to keep free space after the last cell pointer so that new cells can
+** be easily added without having to defragment the page.
+**
+** Cell content is stored at the very end of the page and grows toward the
+** beginning of the page.
+**
+** Unused space within the cell content area is collected into a linked list of
+** freeblocks.  Each freeblock is at least 4 bytes in size.  The byte offset
+** to the first freeblock is given in the header.  Freeblocks occur in
+** increasing order.  Because a freeblock must be at least 4 bytes in size,
+** any group of 3 or fewer unused bytes in the cell content area cannot
+** exist on the freeblock chain.  A group of 3 or fewer free bytes is called
+** a fragment.  The total number of bytes in all fragments is recorded.
+** in the page header at offset 7.
+**
+**    SIZE    DESCRIPTION
+**      2     Byte offset of the next freeblock
+**      2     Bytes in this freeblock
+**
+** Cells are of variable length.  Cells are stored in the cell content area at
+** the end of the page.  Pointers to the cells are in the cell pointer array
+** that immediately follows the page header.  Cells is not necessarily
+** contiguous or in order, but cell pointers are contiguous and in order.
+**
+** Cell content makes use of variable length integers.  A variable
+** length integer is 1 to 9 bytes where the lower 7 bits of each 
+** byte are used.  The integer consists of all bytes that have bit 8 set and
+** the first byte with bit 8 clear.  The most significant byte of the integer
+** appears first.  A variable-length integer may not be more than 9 bytes long.
+** As a special case, all 8 bytes of the 9th byte are used as data.  This
+** allows a 64-bit integer to be encoded in 9 bytes.
+**
+**    0x00                      becomes  0x00000000
+**    0x7f                      becomes  0x0000007f
+**    0x81 0x00                 becomes  0x00000080
+**    0x82 0x00                 becomes  0x00000100
+**    0x80 0x7f                 becomes  0x0000007f
+**    0x8a 0x91 0xd1 0xac 0x78  becomes  0x12345678
+**    0x81 0x81 0x81 0x81 0x01  becomes  0x10204081
+**
+** Variable length integers are used for rowids and to hold the number of
+** bytes of key and data in a btree cell.
+**
+** The content of a cell looks like this:
+**
+**    SIZE    DESCRIPTION
+**      4     Page number of the left child. Omitted if leaf flag is set.
+**     var    Number of bytes of data. Omitted if the zerodata flag is set.
+**     var    Number of bytes of key. Or the key itself if intkey flag is set.
+**      *     Payload
+**      4     First page of the overflow chain.  Omitted if no overflow
+**
+** Overflow pages form a linked list.  Each page except the last is completely
+** filled with data (pagesize - 4 bytes).  The last page can have as little
+** as 1 byte of data.
+**
+**    SIZE    DESCRIPTION
+**      4     Page number of next overflow page
+**      *     Data
+**
+** Freelist pages come in two subtypes: trunk pages and leaf pages.  The
+** file header points to the first in a linked list of trunk page.  Each trunk
+** page points to multiple leaf pages.  The content of a leaf page is
+** unspecified.  A trunk page looks like this:
+**
+**    SIZE    DESCRIPTION
+**      4     Page number of next trunk page
+**      4     Number of leaf pointers on this page
+**      *     zero or more pages numbers of leaves
 */
-static int modifyPagePointer(MemPage *pPage, Pgno iFrom, Pgno iTo, u8 eType){
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( eType==PTRMAP_OVERFLOW2 ){
-    /* The pointer is always the first 4 bytes of the page in this case.  */
-    if( get4byte(pPage->aData)!=iFrom ){
-      return SQLITE_CORRUPT_BKPT;
-    }
-    put4byte(pPage->aData, iTo);
-  }else{
-    int isInitOrig = pPage->isInit;
-    int i;
-    int nCell;
 
-    sqlite3BtreeInitPage(pPage, 0);
-    nCell = pPage->nCell;
 
-    for(i=0; i<nCell; i++){
-      u8 *pCell = findCell(pPage, i);
-      if( eType==PTRMAP_OVERFLOW1 ){
-        CellInfo info;
-        sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-        if( info.iOverflow ){
-          if( iFrom==get4byte(&pCell[info.iOverflow]) ){
-            put4byte(&pCell[info.iOverflow], iTo);
-            break;
-          }
-        }
-      }else{
-        if( get4byte(pCell)==iFrom ){
-          put4byte(pCell, iTo);
-          break;
-        }
-      }
-    }
-  
-    if( i==nCell ){
-      if( eType!=PTRMAP_BTREE || 
-          get4byte(&pPage->aData[pPage->hdrOffset+8])!=iFrom ){
-        return SQLITE_CORRUPT_BKPT;
-      }
-      put4byte(&pPage->aData[pPage->hdrOffset+8], iTo);
-    }
+/* The following value is the maximum cell size assuming a maximum page
+** size give above.
+*/
+#define MX_CELL_SIZE(pBt)  (pBt->pageSize-8)
 
-    pPage->isInit = isInitOrig;
-  }
-  return SQLITE_OK;
-}
+/* The maximum number of cells on a single page of the database.  This
+** assumes a minimum cell size of 6 bytes  (4 bytes for the cell itself
+** plus 2 bytes for the index to the cell in the page header).  Such
+** small cells will be rare, but they are possible.
+*/
+#define MX_CELL(pBt) ((pBt->pageSize-8)/6)
 
+/* Forward declarations */
+typedef struct MemPage MemPage;
+typedef struct BtLock BtLock;
 
 /*
-** Move the open database page pDbPage to location iFreePage in the 
-** database. The pDbPage reference remains valid.
+** This is a magic string that appears at the beginning of every
+** SQLite database in order to identify the file as a real database.
+**
+** You can change this value at compile-time by specifying a
+** -DSQLITE_FILE_HEADER="..." on the compiler command-line.  The
+** header must be exactly 16 bytes including the zero-terminator so
+** the string itself should be 15 characters long.  If you change
+** the header, then your custom library will not be able to read 
+** databases generated by the standard tools and the standard tools
+** will not be able to read databases created by your custom library.
 */
-static int relocatePage(
-  BtShared *pBt,           /* Btree */
-  MemPage *pDbPage,        /* Open page to move */
-  u8 eType,                /* Pointer map 'type' entry for pDbPage */
-  Pgno iPtrPage,           /* Pointer map 'page-no' entry for pDbPage */
-  Pgno iFreePage           /* The location to move pDbPage to */
-){
-  MemPage *pPtrPage;   /* The page that contains a pointer to pDbPage */
-  Pgno iDbPage = pDbPage->pgno;
-  Pager *pPager = pBt->pPager;
-  int rc;
-
-  assert( eType==PTRMAP_OVERFLOW2 || eType==PTRMAP_OVERFLOW1 || 
-      eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE );
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( pDbPage->pBt==pBt );
-
-  /* Move page iDbPage from its current location to page number iFreePage */
-  TRACE(("AUTOVACUUM: Moving %d to free page %d (ptr page %d type %d)\n", 
-      iDbPage, iFreePage, iPtrPage, eType));
-  rc = sqlite3PagerMovepage(pPager, pDbPage->pDbPage, iFreePage);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  pDbPage->pgno = iFreePage;
-
-  /* If pDbPage was a btree-page, then it may have child pages and/or cells
-  ** that point to overflow pages. The pointer map entries for all these
-  ** pages need to be changed.
-  **
-  ** If pDbPage is an overflow page, then the first 4 bytes may store a
-  ** pointer to a subsequent overflow page. If this is the case, then
-  ** the pointer map needs to be updated for the subsequent overflow page.
-  */
-  if( eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE ){
-    rc = setChildPtrmaps(pDbPage);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-  }else{
-    Pgno nextOvfl = get4byte(pDbPage->aData);
-    if( nextOvfl!=0 ){
-      rc = ptrmapPut(pBt, nextOvfl, PTRMAP_OVERFLOW2, iFreePage);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-    }
-  }
-
-  /* Fix the database pointer on page iPtrPage that pointed at iDbPage so
-  ** that it points at iFreePage. Also fix the pointer map entry for
-  ** iPtrPage.
-  */
-  if( eType!=PTRMAP_ROOTPAGE ){
-    rc = sqlite3BtreeGetPage(pBt, iPtrPage, &pPtrPage, 0);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    rc = sqlite3PagerWrite(pPtrPage->pDbPage);
-    if( rc!=SQLITE_OK ){
-      releasePage(pPtrPage);
-      return rc;
-    }
-    rc = modifyPagePointer(pPtrPage, iDbPage, iFreePage, eType);
-    releasePage(pPtrPage);
-    if( rc==SQLITE_OK ){
-      rc = ptrmapPut(pBt, iFreePage, eType, iPtrPage);
-    }
-  }
-  return rc;
-}
+#ifndef SQLITE_FILE_HEADER /* 123456789 123456 */
+#  define SQLITE_FILE_HEADER "SQLite format 3"
+#endif
 
-/* Forward declaration required by incrVacuumStep(). */
-static int allocateBtreePage(BtShared *, MemPage **, Pgno *, Pgno, u8);
+/*
+** Page type flags.  An ORed combination of these flags appear as the
+** first byte of on-disk image of every BTree page.
+*/
+#define PTF_INTKEY    0x01
+#define PTF_ZERODATA  0x02
+#define PTF_LEAFDATA  0x04
+#define PTF_LEAF      0x08
 
 /*
-** Perform a single step of an incremental-vacuum. If successful,
-** return SQLITE_OK. If there is no work to do (and therefore no
-** point in calling this function again), return SQLITE_DONE.
+** As each page of the file is loaded into memory, an instance of the following
+** structure is appended and initialized to zero.  This structure stores
+** information about the page that is decoded from the raw file page.
 **
-** More specificly, this function attempts to re-organize the 
-** database so that the last page of the file currently in use
-** is no longer in use.
+** The pParent field points back to the parent page.  This allows us to
+** walk up the BTree from any leaf to the root.  Care must be taken to
+** unref() the parent page pointer when this page is no longer referenced.
+** The pageDestructor() routine handles that chore.
 **
-** If the nFin parameter is non-zero, the implementation assumes
-** that the caller will keep calling incrVacuumStep() until
-** it returns SQLITE_DONE or an error, and that nFin is the
-** number of pages the database file will contain after this 
-** process is complete.
+** Access to all fields of this structure is controlled by the mutex
+** stored in MemPage.pBt->mutex.
 */
-static int incrVacuumStep(BtShared *pBt, Pgno nFin){
-  Pgno iLastPg;             /* Last page in the database */
-  Pgno nFreeList;           /* Number of pages still on the free-list */
-
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  iLastPg = pBt->nTrunc;
-  if( iLastPg==0 ){
-    iLastPg = sqlite3PagerPagecount(pBt->pPager);
-  }
+struct MemPage {
+  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */
+  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
+  u8 intKey;           /* True if intkey flag is set */
+  u8 leaf;             /* True if leaf flag is set */
+  u8 hasData;          /* True if this page stores data */
+  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
+  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
+  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
+  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
+  u16 cellOffset;      /* Index in aData of first cell pointer */
+  u16 nFree;           /* Number of free bytes on the page */
+  u16 nCell;           /* Number of cells on this page, local and ovfl */
+  u16 maskPage;        /* Mask for page offset */
+  struct _OvflCell {   /* Cells that will not fit on aData[] */
+    u8 *pCell;          /* Pointers to the body of the overflow cell */
+    u16 idx;            /* Insert this cell before idx-th non-overflow cell */
+  } aOvfl[5];
+  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
+  u8 *aData;           /* Pointer to disk image of the page data */
+  DbPage *pDbPage;     /* Pager page handle */
+  Pgno pgno;           /* Page number for this page */
+};
 
-  if( !PTRMAP_ISPAGE(pBt, iLastPg) && iLastPg!=PENDING_BYTE_PAGE(pBt) ){
-    int rc;
-    u8 eType;
-    Pgno iPtrPage;
+/*
+** The in-memory image of a disk page has the auxiliary information appended
+** to the end.  EXTRA_SIZE is the number of bytes of space needed to hold
+** that extra information.
+*/
+#define EXTRA_SIZE sizeof(MemPage)
 
-    nFreeList = get4byte(&pBt->pPage1->aData[36]);
-    if( nFreeList==0 || nFin==iLastPg ){
-      return SQLITE_DONE;
-    }
+/*
+** A linked list of the following structures is stored at BtShared.pLock.
+** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor 
+** is opened on the table with root page BtShared.iTable. Locks are removed
+** from this list when a transaction is committed or rolled back, or when
+** a btree handle is closed.
+*/
+struct BtLock {
+  Btree *pBtree;        /* Btree handle holding this lock */
+  Pgno iTable;          /* Root page of table */
+  u8 eLock;             /* READ_LOCK or WRITE_LOCK */
+  BtLock *pNext;        /* Next in BtShared.pLock list */
+};
 
-    rc = ptrmapGet(pBt, iLastPg, &eType, &iPtrPage);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    if( eType==PTRMAP_ROOTPAGE ){
-      return SQLITE_CORRUPT_BKPT;
-    }
+/* Candidate values for BtLock.eLock */
+#define READ_LOCK     1
+#define WRITE_LOCK    2
 
-    if( eType==PTRMAP_FREEPAGE ){
-      if( nFin==0 ){
-        /* Remove the page from the files free-list. This is not required
-        ** if nFin is non-zero. In that case, the free-list will be
-        ** truncated to zero after this function returns, so it doesn't 
-        ** matter if it still contains some garbage entries.
-        */
-        Pgno iFreePg;
-        MemPage *pFreePg;
-        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, 1);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        assert( iFreePg==iLastPg );
-        releasePage(pFreePg);
-      }
-    } else {
-      Pgno iFreePg;             /* Index of free page to move pLastPg to */
-      MemPage *pLastPg;
+/* A Btree handle
+**
+** A database connection contains a pointer to an instance of
+** this object for every database file that it has open.  This structure
+** is opaque to the database connection.  The database connection cannot
+** see the internals of this structure and only deals with pointers to
+** this structure.
+**
+** For some database files, the same underlying database cache might be 
+** shared between multiple connections.  In that case, each contection
+** has it own pointer to this object.  But each instance of this object
+** points to the same BtShared object.  The database cache and the
+** schema associated with the database file are all contained within
+** the BtShared object.
+**
+** All fields in this structure are accessed under sqlite3.mutex.
+** The pBt pointer itself may not be changed while there exists cursors 
+** in the referenced BtShared that point back to this Btree since those
+** cursors have to do go through this Btree to find their BtShared and
+** they often do so without holding sqlite3.mutex.
+*/
+struct Btree {
+  sqlite3 *db;       /* The database connection holding this btree */
+  BtShared *pBt;     /* Sharable content of this btree */
+  u8 inTrans;        /* TRANS_NONE, TRANS_READ or TRANS_WRITE */
+  u8 sharable;       /* True if we can share pBt with another db */
+  u8 locked;         /* True if db currently has pBt locked */
+  int wantToLock;    /* Number of nested calls to sqlite3BtreeEnter() */
+  int nBackup;       /* Number of backup operations reading this btree */
+  Btree *pNext;      /* List of other sharable Btrees from the same db */
+  Btree *pPrev;      /* Back pointer of the same list */
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  BtLock lock;       /* Object used to lock page 1 */
+#endif
+};
 
-      rc = sqlite3BtreeGetPage(pBt, iLastPg, &pLastPg, 0);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
+/*
+** Btree.inTrans may take one of the following values.
+**
+** If the shared-data extension is enabled, there may be multiple users
+** of the Btree structure. At most one of these may open a write transaction,
+** but any number may have active read transactions.
+*/
+#define TRANS_NONE  0
+#define TRANS_READ  1
+#define TRANS_WRITE 2
 
-      /* If nFin is zero, this loop runs exactly once and page pLastPg
-      ** is swapped with the first free page pulled off the free list.
-      **
-      ** On the other hand, if nFin is greater than zero, then keep
-      ** looping until a free-page located within the first nFin pages
-      ** of the file is found.
-      */
-      do {
-        MemPage *pFreePg;
-        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, 0, 0);
-        if( rc!=SQLITE_OK ){
-          releasePage(pLastPg);
-          return rc;
-        }
-        releasePage(pFreePg);
-      }while( nFin!=0 && iFreePg>nFin );
-      assert( iFreePg<iLastPg );
-      
-      rc = sqlite3PagerWrite(pLastPg->pDbPage);
-      if( rc==SQLITE_OK ){
-        rc = relocatePage(pBt, pLastPg, eType, iPtrPage, iFreePg);
-      }
-      releasePage(pLastPg);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-    }
-  }
+/*
+** An instance of this object represents a single database file.
+** 
+** A single database file can be in use as the same time by two
+** or more database connections.  When two or more connections are
+** sharing the same database file, each connection has it own
+** private Btree object for the file and each of those Btrees points
+** to this one BtShared object.  BtShared.nRef is the number of
+** connections currently sharing this database file.
+**
+** Fields in this structure are accessed under the BtShared.mutex
+** mutex, except for nRef and pNext which are accessed under the
+** global SQLITE_MUTEX_STATIC_MASTER mutex.  The pPager field
+** may not be modified once it is initially set as long as nRef>0.
+** The pSchema field may be set once under BtShared.mutex and
+** thereafter is unchanged as long as nRef>0.
+**
+** isPending:
+**
+**   If a BtShared client fails to obtain a write-lock on a database
+**   table (because there exists one or more read-locks on the table),
+**   the shared-cache enters 'pending-lock' state and isPending is
+**   set to true.
+**
+**   The shared-cache leaves the 'pending lock' state when either of
+**   the following occur:
+**
+**     1) The current writer (BtShared.pWriter) concludes its transaction, OR
+**     2) The number of locks held by other connections drops to zero.
+**
+**   while in the 'pending-lock' state, no connection may start a new
+**   transaction.
+**
+**   This feature is included to help prevent writer-starvation.
+*/
+struct BtShared {
+  Pager *pPager;        /* The page cache */
+  sqlite3 *db;          /* Database connection currently using this Btree */
+  BtCursor *pCursor;    /* A list of all open cursors */
+  MemPage *pPage1;      /* First page of the database */
+  u8 readOnly;          /* True if the underlying file is readonly */
+  u8 pageSizeFixed;     /* True if the page size can no longer be changed */
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  u8 autoVacuum;        /* True if auto-vacuum is enabled */
+  u8 incrVacuum;        /* True if incr-vacuum is enabled */
+#endif
+  u16 pageSize;         /* Total number of bytes on a page */
+  u16 usableSize;       /* Number of usable bytes on each page */
+  u16 maxLocal;         /* Maximum local payload in non-LEAFDATA tables */
+  u16 minLocal;         /* Minimum local payload in non-LEAFDATA tables */
+  u16 maxLeaf;          /* Maximum local payload in a LEAFDATA table */
+  u16 minLeaf;          /* Minimum local payload in a LEAFDATA table */
+  u8 inTransaction;     /* Transaction state */
+  int nTransaction;     /* Number of open transactions (read + write) */
+  void *pSchema;        /* Pointer to space allocated by sqlite3BtreeSchema() */
+  void (*xFreeSchema)(void*);  /* Destructor for BtShared.pSchema */
+  sqlite3_mutex *mutex; /* Non-recursive mutex required to access this struct */
+  Bitvec *pHasContent;  /* Set of pages moved to free-list this transaction */
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  int nRef;             /* Number of references to this structure */
+  BtShared *pNext;      /* Next on a list of sharable BtShared structs */
+  BtLock *pLock;        /* List of locks held on this shared-btree struct */
+  Btree *pWriter;       /* Btree with currently open write transaction */
+  u8 isExclusive;       /* True if pWriter has an EXCLUSIVE lock on the db */
+  u8 isPending;         /* If waiting for read-locks to clear */
+#endif
+  u8 *pTmpSpace;        /* BtShared.pageSize bytes of space for tmp use */
+};
 
-  pBt->nTrunc = iLastPg - 1;
-  while( pBt->nTrunc==PENDING_BYTE_PAGE(pBt)||PTRMAP_ISPAGE(pBt, pBt->nTrunc) ){
-    pBt->nTrunc--;
-  }
-  return SQLITE_OK;
-}
+/*
+** An instance of the following structure is used to hold information
+** about a cell.  The parseCellPtr() function fills in this structure
+** based on information extract from the raw disk page.
+*/
+typedef struct CellInfo CellInfo;
+struct CellInfo {
+  u8 *pCell;     /* Pointer to the start of cell content */
+  i64 nKey;      /* The key for INTKEY tables, or number of bytes in key */
+  u32 nData;     /* Number of bytes of data */
+  u32 nPayload;  /* Total amount of payload */
+  u16 nHeader;   /* Size of the cell content header in bytes */
+  u16 nLocal;    /* Amount of payload held locally */
+  u16 iOverflow; /* Offset to overflow page number.  Zero if no overflow */
+  u16 nSize;     /* Size of the cell content on the main b-tree page */
+};
 
 /*
-** A write-transaction must be opened before calling this function.
-** It performs a single unit of work towards an incremental vacuum.
+** Maximum depth of an SQLite B-Tree structure. Any B-Tree deeper than
+** this will be declared corrupt. This value is calculated based on a
+** maximum database size of 2^31 pages a minimum fanout of 2 for a
+** root-node and 3 for all other internal nodes.
 **
-** If the incremental vacuum is finished after this function has run,
-** SQLITE_DONE is returned. If it is not finished, but no error occured,
-** SQLITE_OK is returned. Otherwise an SQLite error code. 
+** If a tree that appears to be taller than this is encountered, it is
+** assumed that the database is corrupt.
 */
-SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *p){
-  int rc;
-  BtShared *pBt = p->pBt;
-
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  assert( pBt->inTransaction==TRANS_WRITE && p->inTrans==TRANS_WRITE );
-  if( !pBt->autoVacuum ){
-    rc = SQLITE_DONE;
-  }else{
-    invalidateAllOverflowCache(pBt);
-    rc = incrVacuumStep(pBt, 0);
-  }
-  sqlite3BtreeLeave(p);
-  return rc;
-}
+#define BTCURSOR_MAX_DEPTH 20
 
 /*
-** This routine is called prior to sqlite3PagerCommit when a transaction
-** is commited for an auto-vacuum database.
+** A cursor is a pointer to a particular entry within a particular
+** b-tree within a database file.
 **
-** If SQLITE_OK is returned, then *pnTrunc is set to the number of pages
-** the database file should be truncated to during the commit process. 
-** i.e. the database has been reorganized so that only the first *pnTrunc
-** pages are in use.
+** The entry is identified by its MemPage and the index in
+** MemPage.aCell[] of the entry.
+**
+** When a single database file can shared by two more database connections,
+** but cursors cannot be shared.  Each cursor is associated with a
+** particular database connection identified BtCursor.pBtree.db.
+**
+** Fields in this structure are accessed under the BtShared.mutex
+** found at self->pBt->mutex. 
 */
-static int autoVacuumCommit(BtShared *pBt, Pgno *pnTrunc){
-  int rc = SQLITE_OK;
-  Pager *pPager = pBt->pPager;
-#ifndef NDEBUG
-  int nRef = sqlite3PagerRefcount(pPager);
+struct BtCursor {
+  Btree *pBtree;            /* The Btree to which this cursor belongs */
+  BtShared *pBt;            /* The BtShared this cursor points to */
+  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
+  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
+  Pgno pgnoRoot;            /* The root page of this tree */
+  sqlite3_int64 cachedRowid; /* Next rowid cache.  0 means not valid */
+  CellInfo info;            /* A parse of the cell we are pointing at */
+  u8 wrFlag;                /* True if writable */
+  u8 atLast;                /* Cursor pointing to the last entry */
+  u8 validNKey;             /* True if info.nKey is valid */
+  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
+  void *pKey;      /* Saved key that was cursor's last known position */
+  i64 nKey;        /* Size of pKey, or last integer key */
+  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */
+#ifndef SQLITE_OMIT_INCRBLOB
+  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
+  Pgno *aOverflow;          /* Cache of overflow page locations */
 #endif
+  i16 iPage;                            /* Index of current page in apPage */
+  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
+  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
+};
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  invalidateAllOverflowCache(pBt);
-  assert(pBt->autoVacuum);
-  if( !pBt->incrVacuum ){
-    Pgno nFin = 0;
-
-    if( pBt->nTrunc==0 ){
-      Pgno nFree;
-      Pgno nPtrmap;
-      const int pgsz = pBt->pageSize;
-      Pgno nOrig = sqlite3PagerPagecount(pBt->pPager);
-
-      if( PTRMAP_ISPAGE(pBt, nOrig) ){
-        return SQLITE_CORRUPT_BKPT;
-      }
-      if( nOrig==PENDING_BYTE_PAGE(pBt) ){
-        nOrig--;
-      }
-      nFree = get4byte(&pBt->pPage1->aData[36]);
-      nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+pgsz/5)/(pgsz/5);
-      nFin = nOrig - nFree - nPtrmap;
-      if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<=PENDING_BYTE_PAGE(pBt) ){
-        nFin--;
-      }
-      while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
-        nFin--;
-      }
-    }
-
-    while( rc==SQLITE_OK ){
-      rc = incrVacuumStep(pBt, nFin);
-    }
-    if( rc==SQLITE_DONE ){
-      assert(nFin==0 || pBt->nTrunc==0 || nFin<=pBt->nTrunc);
-      rc = SQLITE_OK;
-      if( pBt->nTrunc && nFin ){
-        rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
-        put4byte(&pBt->pPage1->aData[32], 0);
-        put4byte(&pBt->pPage1->aData[36], 0);
-        pBt->nTrunc = nFin;
-      }
-    }
-    if( rc!=SQLITE_OK ){
-      sqlite3PagerRollback(pPager);
-    }
-  }
+/*
+** Potential values for BtCursor.eState.
+**
+** CURSOR_VALID:
+**   Cursor points to a valid entry. getPayload() etc. may be called.
+**
+** CURSOR_INVALID:
+**   Cursor does not point to a valid entry. This can happen (for example) 
+**   because the table is empty or because BtreeCursorFirst() has not been
+**   called.
+**
+** CURSOR_REQUIRESEEK:
+**   The table that this cursor was opened on still exists, but has been 
+**   modified since the cursor was last used. The cursor position is saved
+**   in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in 
+**   this state, restoreCursorPosition() can be called to attempt to
+**   seek the cursor to the saved position.
+**
+** CURSOR_FAULT:
+**   A unrecoverable error (an I/O error or a malloc failure) has occurred
+**   on a different connection that shares the BtShared cache with this
+**   cursor.  The error has left the cache in an inconsistent state.
+**   Do nothing else with this cursor.  Any attempt to use the cursor
+**   should return the error code stored in BtCursor.skip
+*/
+#define CURSOR_INVALID           0
+#define CURSOR_VALID             1
+#define CURSOR_REQUIRESEEK       2
+#define CURSOR_FAULT             3
 
-  if( rc==SQLITE_OK ){
-    *pnTrunc = pBt->nTrunc;
-    pBt->nTrunc = 0;
-  }
-  assert( nRef==sqlite3PagerRefcount(pPager) );
-  return rc;
-}
+/* 
+** The database page the PENDING_BYTE occupies. This page is never used.
+*/
+# define PENDING_BYTE_PAGE(pBt) PAGER_MJ_PGNO(pBt)
 
-#endif
+/*
+** These macros define the location of the pointer-map entry for a 
+** database page. The first argument to each is the number of usable
+** bytes on each page of the database (often 1024). The second is the
+** page number to look up in the pointer map.
+**
+** PTRMAP_PAGENO returns the database page number of the pointer-map
+** page that stores the required pointer. PTRMAP_PTROFFSET returns
+** the offset of the requested map entry.
+**
+** If the pgno argument passed to PTRMAP_PAGENO is a pointer-map page,
+** then pgno is returned. So (pgno==PTRMAP_PAGENO(pgsz, pgno)) can be
+** used to test if pgno is a pointer-map page. PTRMAP_ISPAGE implements
+** this test.
+*/
+#define PTRMAP_PAGENO(pBt, pgno) ptrmapPageno(pBt, pgno)
+#define PTRMAP_PTROFFSET(pgptrmap, pgno) (5*(pgno-pgptrmap-1))
+#define PTRMAP_ISPAGE(pBt, pgno) (PTRMAP_PAGENO((pBt),(pgno))==(pgno))
 
 /*
-** This routine does the first phase of a two-phase commit.  This routine
-** causes a rollback journal to be created (if it does not already exist)
-** and populated with enough information so that if a power loss occurs
-** the database can be restored to its original state by playing back
-** the journal.  Then the contents of the journal are flushed out to
-** the disk.  After the journal is safely on oxide, the changes to the
-** database are written into the database file and flushed to oxide.
-** At the end of this call, the rollback journal still exists on the
-** disk and we are still holding all locks, so the transaction has not
-** committed.  See sqlite3BtreeCommit() for the second phase of the
-** commit process.
+** The pointer map is a lookup table that identifies the parent page for
+** each child page in the database file.  The parent page is the page that
+** contains a pointer to the child.  Every page in the database contains
+** 0 or 1 parent pages.  (In this context 'database page' refers
+** to any page that is not part of the pointer map itself.)  Each pointer map
+** entry consists of a single byte 'type' and a 4 byte parent page number.
+** The PTRMAP_XXX identifiers below are the valid types.
 **
-** This call is a no-op if no write-transaction is currently active on pBt.
+** The purpose of the pointer map is to facility moving pages from one
+** position in the file to another as part of autovacuum.  When a page
+** is moved, the pointer in its parent must be updated to point to the
+** new location.  The pointer map is used to locate the parent page quickly.
 **
-** Otherwise, sync the database file for the btree pBt. zMaster points to
-** the name of a master journal file that should be written into the
-** individual journal file, or is NULL, indicating no master journal file 
-** (single database transaction).
+** PTRMAP_ROOTPAGE: The database page is a root-page. The page-number is not
+**                  used in this case.
 **
-** When this is called, the master journal should already have been
-** created, populated with this journal pointer and synced to disk.
+** PTRMAP_FREEPAGE: The database page is an unused (free) page. The page-number 
+**                  is not used in this case.
 **
-** Once this is routine has returned, the only thing required to commit
-** the write-transaction for this database file is to delete the journal.
+** PTRMAP_OVERFLOW1: The database page is the first page in a list of 
+**                   overflow pages. The page number identifies the page that
+**                   contains the cell with a pointer to this overflow page.
+**
+** PTRMAP_OVERFLOW2: The database page is the second or later page in a list of
+**                   overflow pages. The page-number identifies the previous
+**                   page in the overflow page list.
+**
+** PTRMAP_BTREE: The database page is a non-root btree page. The page number
+**               identifies the parent page in the btree.
+*/
+#define PTRMAP_ROOTPAGE 1
+#define PTRMAP_FREEPAGE 2
+#define PTRMAP_OVERFLOW1 3
+#define PTRMAP_OVERFLOW2 4
+#define PTRMAP_BTREE 5
+
+/* A bunch of assert() statements to check the transaction state variables
+** of handle p (type Btree*) are internally consistent.
+*/
+#define btreeIntegrity(p) \
+  assert( p->pBt->inTransaction!=TRANS_NONE || p->pBt->nTransaction==0 ); \
+  assert( p->pBt->inTransaction>=p->inTrans ); 
+
+
+/*
+** The ISAUTOVACUUM macro is used within balance_nonroot() to determine
+** if the database supports auto-vacuum or not. Because it is used
+** within an expression that is an argument to another macro 
+** (sqliteMallocRaw), it is not possible to use conditional compilation.
+** So, this macro is defined instead.
 */
-SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
-  int rc = SQLITE_OK;
-  if( p->inTrans==TRANS_WRITE ){
-    BtShared *pBt = p->pBt;
-    Pgno nTrunc = 0;
-    sqlite3BtreeEnter(p);
-    pBt->db = p->db;
 #ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pBt->autoVacuum ){
-      rc = autoVacuumCommit(pBt, &nTrunc); 
-      if( rc!=SQLITE_OK ){
-        sqlite3BtreeLeave(p);
-        return rc;
-      }
-    }
+#define ISAUTOVACUUM (pBt->autoVacuum)
+#else
+#define ISAUTOVACUUM 0
 #endif
-    rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, nTrunc, 0);
-    sqlite3BtreeLeave(p);
-  }
-  return rc;
+
+
+/*
+** This structure is passed around through all the sanity checking routines
+** in order to keep track of some global state information.
+*/
+typedef struct IntegrityCk IntegrityCk;
+struct IntegrityCk {
+  BtShared *pBt;    /* The tree being checked out */
+  Pager *pPager;    /* The associated pager.  Also accessible by pBt->pPager */
+  Pgno nPage;       /* Number of pages in the database */
+  int *anRef;       /* Number of times each page is referenced */
+  int mxErr;        /* Stop accumulating errors when this reaches zero */
+  int nErr;         /* Number of messages written to zErrMsg so far */
+  int mallocFailed; /* A memory allocation error has occurred */
+  StrAccum errMsg;  /* Accumulate the error message text here */
+};
+
+/*
+** Read or write a two- and four-byte big-endian integer values.
+*/
+#define get2byte(x)   ((x)[0]<<8 | (x)[1])
+#define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v))
+#define get4byte sqlite3Get4byte
+#define put4byte sqlite3Put4byte
+
+/************** End of btreeInt.h ********************************************/
+/************** Continuing where we left off in btmutex.c ********************/
+#ifndef SQLITE_OMIT_SHARED_CACHE
+#if SQLITE_THREADSAFE
+
+/*
+** Obtain the BtShared mutex associated with B-Tree handle p. Also,
+** set BtShared.db to the database handle associated with p and the
+** p->locked boolean to true.
+*/
+static void lockBtreeMutex(Btree *p){
+  assert( p->locked==0 );
+  assert( sqlite3_mutex_notheld(p->pBt->mutex) );
+  assert( sqlite3_mutex_held(p->db->mutex) );
+
+  sqlite3_mutex_enter(p->pBt->mutex);
+  p->pBt->db = p->db;
+  p->locked = 1;
 }
 
 /*
-** Commit the transaction currently in progress.
+** Release the BtShared mutex associated with B-Tree handle p and
+** clear the p->locked boolean.
+*/
+static void unlockBtreeMutex(Btree *p){
+  assert( p->locked==1 );
+  assert( sqlite3_mutex_held(p->pBt->mutex) );
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  assert( p->db==p->pBt->db );
+
+  sqlite3_mutex_leave(p->pBt->mutex);
+  p->locked = 0;
+}
+
+/*
+** Enter a mutex on the given BTree object.
 **
-** This routine implements the second phase of a 2-phase commit.  The
-** sqlite3BtreeSync() routine does the first phase and should be invoked
-** prior to calling this routine.  The sqlite3BtreeSync() routine did
-** all the work of writing information out to disk and flushing the
-** contents so that they are written onto the disk platter.  All this
-** routine has to do is delete or truncate the rollback journal
-** (which causes the transaction to commit) and drop locks.
+** If the object is not sharable, then no mutex is ever required
+** and this routine is a no-op.  The underlying mutex is non-recursive.
+** But we keep a reference count in Btree.wantToLock so the behavior
+** of this interface is recursive.
 **
-** This will release the write lock on the database file.  If there
-** are no active cursors, it also releases the read lock.
+** To avoid deadlocks, multiple Btrees are locked in the same order
+** by all database connections.  The p->pNext is a list of other
+** Btrees belonging to the same database connection as the p Btree
+** which need to be locked after p.  If we cannot get a lock on
+** p, then first unlock all of the others on p->pNext, then wait
+** for the lock to become available on p, then relock all of the
+** subsequent Btrees that desire a lock.
 */
-SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree *p){
-  BtShared *pBt = p->pBt;
+SQLITE_PRIVATE void sqlite3BtreeEnter(Btree *p){
+  Btree *pLater;
 
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  btreeIntegrity(p);
+  /* Some basic sanity checking on the Btree.  The list of Btrees
+  ** connected by pNext and pPrev should be in sorted order by
+  ** Btree.pBt value. All elements of the list should belong to
+  ** the same connection. Only shared Btrees are on the list. */
+  assert( p->pNext==0 || p->pNext->pBt>p->pBt );
+  assert( p->pPrev==0 || p->pPrev->pBt<p->pBt );
+  assert( p->pNext==0 || p->pNext->db==p->db );
+  assert( p->pPrev==0 || p->pPrev->db==p->db );
+  assert( p->sharable || (p->pNext==0 && p->pPrev==0) );
 
-  /* If the handle has a write-transaction open, commit the shared-btrees 
-  ** transaction and set the shared state to TRANS_READ.
+  /* Check for locking consistency */
+  assert( !p->locked || p->wantToLock>0 );
+  assert( p->sharable || p->wantToLock==0 );
+
+  /* We should already hold a lock on the database connection */
+  assert( sqlite3_mutex_held(p->db->mutex) );
+
+  /* Unless the database is sharable and unlocked, then BtShared.db
+  ** should already be set correctly. */
+  assert( (p->locked==0 && p->sharable) || p->pBt->db==p->db );
+
+  if( !p->sharable ) return;
+  p->wantToLock++;
+  if( p->locked ) return;
+
+  /* In most cases, we should be able to acquire the lock we
+  ** want without having to go throught the ascending lock
+  ** procedure that follows.  Just be sure not to block.
   */
-  if( p->inTrans==TRANS_WRITE ){
-    int rc;
-    assert( pBt->inTransaction==TRANS_WRITE );
-    assert( pBt->nTransaction>0 );
-    rc = sqlite3PagerCommitPhaseTwo(pBt->pPager);
-    if( rc!=SQLITE_OK ){
-      sqlite3BtreeLeave(p);
-      return rc;
-    }
-    pBt->inTransaction = TRANS_READ;
-    pBt->inStmt = 0;
+  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
+    p->pBt->db = p->db;
+    p->locked = 1;
+    return;
   }
-  unlockAllTables(p);
 
-  /* If the handle has any kind of transaction open, decrement the transaction
-  ** count of the shared btree. If the transaction count reaches 0, set
-  ** the shared state to TRANS_NONE. The unlockBtreeIfUnused() call below
-  ** will unlock the pager.
+  /* To avoid deadlock, first release all locks with a larger
+  ** BtShared address.  Then acquire our lock.  Then reacquire
+  ** the other BtShared locks that we used to hold in ascending
+  ** order.
   */
-  if( p->inTrans!=TRANS_NONE ){
-    pBt->nTransaction--;
-    if( 0==pBt->nTransaction ){
-      pBt->inTransaction = TRANS_NONE;
+  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
+    assert( pLater->sharable );
+    assert( pLater->pNext==0 || pLater->pNext->pBt>pLater->pBt );
+    assert( !pLater->locked || pLater->wantToLock>0 );
+    if( pLater->locked ){
+      unlockBtreeMutex(pLater);
+    }
+  }
+  lockBtreeMutex(p);
+  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
+    if( pLater->wantToLock ){
+      lockBtreeMutex(pLater);
     }
   }
-
-  /* Set the handles current transaction state to TRANS_NONE and unlock
-  ** the pager if this call closed the only read or write transaction.
-  */
-  p->inTrans = TRANS_NONE;
-  unlockBtreeIfUnused(pBt);
-
-  btreeIntegrity(p);
-  sqlite3BtreeLeave(p);
-  return SQLITE_OK;
 }
 
 /*
-** Do both phases of a commit.
+** Exit the recursive mutex on a Btree.
 */
-SQLITE_PRIVATE int sqlite3BtreeCommit(Btree *p){
-  int rc;
-  sqlite3BtreeEnter(p);
-  rc = sqlite3BtreeCommitPhaseOne(p, 0);
-  if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeCommitPhaseTwo(p);
+SQLITE_PRIVATE void sqlite3BtreeLeave(Btree *p){
+  if( p->sharable ){
+    assert( p->wantToLock>0 );
+    p->wantToLock--;
+    if( p->wantToLock==0 ){
+      unlockBtreeMutex(p);
+    }
   }
-  sqlite3BtreeLeave(p);
-  return rc;
 }
 
 #ifndef NDEBUG
 /*
-** Return the number of write-cursors open on this handle. This is for use
-** in assert() expressions, so it is only compiled if NDEBUG is not
-** defined.
+** Return true if the BtShared mutex is held on the btree, or if the
+** B-Tree is not marked as sharable.
 **
-** For the purposes of this routine, a write-cursor is any cursor that
-** is capable of writing to the databse.  That means the cursor was
-** originally opened for writing and the cursor has not be disabled
-** by having its state changed to CURSOR_FAULT.
+** This routine is used only from within assert() statements.
 */
-static int countWriteCursors(BtShared *pBt){
-  BtCursor *pCur;
-  int r = 0;
-  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
-    if( pCur->wrFlag && pCur->eState!=CURSOR_FAULT ) r++; 
-  }
-  return r;
+SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree *p){
+  assert( p->sharable==0 || p->locked==0 || p->wantToLock>0 );
+  assert( p->sharable==0 || p->locked==0 || p->db==p->pBt->db );
+  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->pBt->mutex) );
+  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->db->mutex) );
+
+  return (p->sharable==0 || p->locked);
 }
 #endif
 
+
+#ifndef SQLITE_OMIT_INCRBLOB
 /*
-** This routine sets the state to CURSOR_FAULT and the error
-** code to errCode for every cursor on BtShared that pBtree
-** references.
-**
-** Every cursor is tripped, including cursors that belong
-** to other database connections that happen to be sharing
-** the cache with pBtree.
-**
-** This routine gets called when a rollback occurs.
-** All cursors using the same cache must be tripped
-** to prevent them from trying to use the btree after
-** the rollback.  The rollback may have deleted tables
-** or moved root pages, so it is not sufficient to
-** save the state of the cursor.  The cursor must be
-** invalidated.
+** Enter and leave a mutex on a Btree given a cursor owned by that
+** Btree.  These entry points are used by incremental I/O and can be
+** omitted if that module is not used.
 */
-SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode){
-  BtCursor *p;
-  sqlite3BtreeEnter(pBtree);
-  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
-    clearCursorPosition(p);
-    p->eState = CURSOR_FAULT;
-    p->skip = errCode;
-  }
-  sqlite3BtreeLeave(pBtree);
+SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor *pCur){
+  sqlite3BtreeEnter(pCur->pBtree);
 }
+SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor *pCur){
+  sqlite3BtreeLeave(pCur->pBtree);
+}
+#endif /* SQLITE_OMIT_INCRBLOB */
+
 
 /*
-** Rollback the transaction in progress.  All cursors will be
-** invalided by this operation.  Any attempt to use a cursor
-** that was open at the beginning of this operation will result
-** in an error.
+** Enter the mutex on every Btree associated with a database
+** connection.  This is needed (for example) prior to parsing
+** a statement since we will be comparing table and column names
+** against all schemas and we do not want those schemas being
+** reset out from under us.
 **
-** This will release the write lock on the database file.  If there
-** are no active cursors, it also releases the read lock.
+** There is a corresponding leave-all procedures.
+**
+** Enter the mutexes in accending order by BtShared pointer address
+** to avoid the possibility of deadlock when two threads with
+** two or more btrees in common both try to lock all their btrees
+** at the same instant.
 */
-SQLITE_PRIVATE int sqlite3BtreeRollback(Btree *p){
-  int rc;
-  BtShared *pBt = p->pBt;
-  MemPage *pPage1;
+SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3 *db){
+  int i;
+  Btree *p, *pLater;
+  assert( sqlite3_mutex_held(db->mutex) );
+  for(i=0; i<db->nDb; i++){
+    p = db->aDb[i].pBt;
+    assert( !p || (p->locked==0 && p->sharable) || p->pBt->db==p->db );
+    if( p && p->sharable ){
+      p->wantToLock++;
+      if( !p->locked ){
+        assert( p->wantToLock==1 );
+        while( p->pPrev ) p = p->pPrev;
+        /* Reason for ALWAYS:  There must be at least on unlocked Btree in
+        ** the chain.  Otherwise the !p->locked test above would have failed */
+        while( p->locked && ALWAYS(p->pNext) ) p = p->pNext;
+        for(pLater = p->pNext; pLater; pLater=pLater->pNext){
+          if( pLater->locked ){
+            unlockBtreeMutex(pLater);
+          }
+        }
+        while( p ){
+          lockBtreeMutex(p);
+          p = p->pNext;
+        }
+      }
+    }
+  }
+}
+SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3 *db){
+  int i;
+  Btree *p;
+  assert( sqlite3_mutex_held(db->mutex) );
+  for(i=0; i<db->nDb; i++){
+    p = db->aDb[i].pBt;
+    if( p && p->sharable ){
+      assert( p->wantToLock>0 );
+      p->wantToLock--;
+      if( p->wantToLock==0 ){
+        unlockBtreeMutex(p);
+      }
+    }
+  }
+}
 
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  rc = saveAllCursors(pBt, 0, 0);
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  if( rc!=SQLITE_OK ){
-    /* This is a horrible situation. An IO or malloc() error occured whilst
-    ** trying to save cursor positions. If this is an automatic rollback (as
-    ** the result of a constraint, malloc() failure or IO error) then 
-    ** the cache may be internally inconsistent (not contain valid trees) so
-    ** we cannot simply return the error to the caller. Instead, abort 
-    ** all queries that may be using any of the cursors that failed to save.
-    */
-    sqlite3BtreeTripAllCursors(p, rc);
+#ifndef NDEBUG
+/*
+** Return true if the current thread holds the database connection
+** mutex and all required BtShared mutexes.
+**
+** This routine is used inside assert() statements only.
+*/
+SQLITE_PRIVATE int sqlite3BtreeHoldsAllMutexes(sqlite3 *db){
+  int i;
+  if( !sqlite3_mutex_held(db->mutex) ){
+    return 0;
+  }
+  for(i=0; i<db->nDb; i++){
+    Btree *p;
+    p = db->aDb[i].pBt;
+    if( p && p->sharable &&
+         (p->wantToLock==0 || !sqlite3_mutex_held(p->pBt->mutex)) ){
+      return 0;
+    }
+  }
+  return 1;
+}
+#endif /* NDEBUG */
+
+/*
+** Add a new Btree pointer to a BtreeMutexArray. 
+** if the pointer can possibly be shared with
+** another database connection.
+**
+** The pointers are kept in sorted order by pBtree->pBt.  That
+** way when we go to enter all the mutexes, we can enter them
+** in order without every having to backup and retry and without
+** worrying about deadlock.
+**
+** The number of shared btrees will always be small (usually 0 or 1)
+** so an insertion sort is an adequate algorithm here.
+*/
+SQLITE_PRIVATE void sqlite3BtreeMutexArrayInsert(BtreeMutexArray *pArray, Btree *pBtree){
+  int i, j;
+  BtShared *pBt;
+  if( pBtree==0 || pBtree->sharable==0 ) return;
+#ifndef NDEBUG
+  {
+    for(i=0; i<pArray->nMutex; i++){
+      assert( pArray->aBtree[i]!=pBtree );
+    }
   }
 #endif
-  btreeIntegrity(p);
-  unlockAllTables(p);
+  assert( pArray->nMutex>=0 );
+  assert( pArray->nMutex<ArraySize(pArray->aBtree)-1 );
+  pBt = pBtree->pBt;
+  for(i=0; i<pArray->nMutex; i++){
+    assert( pArray->aBtree[i]!=pBtree );
+    if( pArray->aBtree[i]->pBt>pBt ){
+      for(j=pArray->nMutex; j>i; j--){
+        pArray->aBtree[j] = pArray->aBtree[j-1];
+      }
+      pArray->aBtree[i] = pBtree;
+      pArray->nMutex++;
+      return;
+    }
+  }
+  pArray->aBtree[pArray->nMutex++] = pBtree;
+}
 
-  if( p->inTrans==TRANS_WRITE ){
-    int rc2;
+/*
+** Enter the mutex of every btree in the array.  This routine is
+** called at the beginning of sqlite3VdbeExec().  The mutexes are
+** exited at the end of the same function.
+*/
+SQLITE_PRIVATE void sqlite3BtreeMutexArrayEnter(BtreeMutexArray *pArray){
+  int i;
+  for(i=0; i<pArray->nMutex; i++){
+    Btree *p = pArray->aBtree[i];
+    /* Some basic sanity checking */
+    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
+    assert( !p->locked || p->wantToLock>0 );
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    pBt->nTrunc = 0;
-#endif
+    /* We should already hold a lock on the database connection */
+    assert( sqlite3_mutex_held(p->db->mutex) );
 
-    assert( TRANS_WRITE==pBt->inTransaction );
-    rc2 = sqlite3PagerRollback(pBt->pPager);
-    if( rc2!=SQLITE_OK ){
-      rc = rc2;
+    /* The Btree is sharable because only sharable Btrees are entered
+    ** into the array in the first place. */
+    assert( p->sharable );
+
+    p->wantToLock++;
+    if( !p->locked ){
+      lockBtreeMutex(p);
     }
+  }
+}
 
-    /* The rollback may have destroyed the pPage1->aData value.  So
-    ** call sqlite3BtreeGetPage() on page 1 again to make
-    ** sure pPage1->aData is set correctly. */
-    if( sqlite3BtreeGetPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
-      releasePage(pPage1);
+/*
+** Leave the mutex of every btree in the group.
+*/
+SQLITE_PRIVATE void sqlite3BtreeMutexArrayLeave(BtreeMutexArray *pArray){
+  int i;
+  for(i=0; i<pArray->nMutex; i++){
+    Btree *p = pArray->aBtree[i];
+    /* Some basic sanity checking */
+    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
+    assert( p->locked );
+    assert( p->wantToLock>0 );
+
+    /* We should already hold a lock on the database connection */
+    assert( sqlite3_mutex_held(p->db->mutex) );
+
+    p->wantToLock--;
+    if( p->wantToLock==0 ){
+      unlockBtreeMutex(p);
     }
-    assert( countWriteCursors(pBt)==0 );
-    pBt->inTransaction = TRANS_READ;
   }
+}
 
-  if( p->inTrans!=TRANS_NONE ){
-    assert( pBt->nTransaction>0 );
-    pBt->nTransaction--;
-    if( 0==pBt->nTransaction ){
-      pBt->inTransaction = TRANS_NONE;
+#else
+SQLITE_PRIVATE void sqlite3BtreeEnter(Btree *p){
+  p->pBt->db = p->db;
+}
+SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3 *db){
+  int i;
+  for(i=0; i<db->nDb; i++){
+    Btree *p = db->aDb[i].pBt;
+    if( p ){
+      p->pBt->db = p->db;
     }
   }
+}
+#endif /* if SQLITE_THREADSAFE */
+#endif /* ifndef SQLITE_OMIT_SHARED_CACHE */
 
-  p->inTrans = TRANS_NONE;
-  pBt->inStmt = 0;
-  unlockBtreeIfUnused(pBt);
+/************** End of btmutex.c *********************************************/
+/************** Begin file btree.c *******************************************/
+/*
+** 2004 April 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** $Id: btree.c,v 1.705 2009/08/10 03:57:58 shane Exp $
+**
+** This file implements a external (disk-based) database using BTrees.
+** See the header comment on "btreeInt.h" for additional information.
+** Including a description of file format and an overview of operation.
+*/
 
-  btreeIntegrity(p);
-  sqlite3BtreeLeave(p);
-  return rc;
-}
+/*
+** The header string that appears at the beginning of every
+** SQLite database.
+*/
+static const char zMagicHeader[] = SQLITE_FILE_HEADER;
+
+/*
+** Set this global variable to 1 to enable tracing using the TRACE
+** macro.
+*/
+#if 0
+int sqlite3BtreeTrace=1;  /* True to enable tracing */
+# define TRACE(X)  if(sqlite3BtreeTrace){printf X;fflush(stdout);}
+#else
+# define TRACE(X)
+#endif
 
+
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** Start a statement subtransaction.  The subtransaction can
-** can be rolled back independently of the main transaction.
-** You must start a transaction before starting a subtransaction.
-** The subtransaction is ended automatically if the main transaction
-** commits or rolls back.
+** A list of BtShared objects that are eligible for participation
+** in shared cache.  This variable has file scope during normal builds,
+** but the test harness needs to access it so we make it global for 
+** test builds.
 **
-** Only one subtransaction may be active at a time.  It is an error to try
-** to start a new subtransaction if another subtransaction is already active.
+** Access to this variable is protected by SQLITE_MUTEX_STATIC_MASTER.
+*/
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE BtShared *SQLITE_WSD sqlite3SharedCacheList = 0;
+#else
+static BtShared *SQLITE_WSD sqlite3SharedCacheList = 0;
+#endif
+#endif /* SQLITE_OMIT_SHARED_CACHE */
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+/*
+** Enable or disable the shared pager and schema features.
 **
-** Statement subtransactions are used around individual SQL statements
-** that are contained within a BEGIN...COMMIT block.  If a constraint
-** error occurs within the statement, the effect of that one statement
-** can be rolled back without having to rollback the entire transaction.
+** This routine has no effect on existing database connections.
+** The shared cache setting effects only future calls to
+** sqlite3_open(), sqlite3_open16(), or sqlite3_open_v2().
 */
-SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree *p){
-  int rc;
-  BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  if( (p->inTrans!=TRANS_WRITE) || pBt->inStmt ){
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-  }else{
-    assert( pBt->inTransaction==TRANS_WRITE );
-    rc = pBt->readOnly ? SQLITE_OK : sqlite3PagerStmtBegin(pBt->pPager);
-    pBt->inStmt = 1;
-  }
-  sqlite3BtreeLeave(p);
-  return rc;
+SQLITE_API int sqlite3_enable_shared_cache(int enable){
+  sqlite3GlobalConfig.sharedCacheEnabled = enable;
+  return SQLITE_OK;
 }
+#endif
+
+
+
+#ifdef SQLITE_OMIT_SHARED_CACHE
+  /*
+  ** The functions querySharedCacheTableLock(), setSharedCacheTableLock(),
+  ** and clearAllSharedCacheTableLocks()
+  ** manipulate entries in the BtShared.pLock linked list used to store
+  ** shared-cache table level locks. If the library is compiled with the
+  ** shared-cache feature disabled, then there is only ever one user
+  ** of each BtShared structure and so this locking is not necessary. 
+  ** So define the lock related functions as no-ops.
+  */
+  #define querySharedCacheTableLock(a,b,c) SQLITE_OK
+  #define setSharedCacheTableLock(a,b,c) SQLITE_OK
+  #define clearAllSharedCacheTableLocks(a)
+  #define downgradeAllSharedCacheTableLocks(a)
+  #define hasSharedCacheTableLock(a,b,c,d) 1
+  #define hasReadConflicts(a, b) 0
+#endif
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
 
+#ifdef SQLITE_DEBUG
 /*
-** Commit the statment subtransaction currently in progress.  If no
-** subtransaction is active, this is a no-op.
-*/
-SQLITE_PRIVATE int sqlite3BtreeCommitStmt(Btree *p){
-  int rc;
-  BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  if( pBt->inStmt && !pBt->readOnly ){
-    rc = sqlite3PagerStmtCommit(pBt->pPager);
+** This function is only used as part of an assert() statement. It checks
+** that connection p holds the required locks to read or write to the 
+** b-tree with root page iRoot. If so, true is returned. Otherwise, false. 
+** For example, when writing to a table b-tree with root-page iRoot via 
+** Btree connection pBtree:
+**
+**    assert( hasSharedCacheTableLock(pBtree, iRoot, 0, WRITE_LOCK) );
+**
+** When writing to an index b-tree that resides in a sharable database, the 
+** caller should have first obtained a lock specifying the root page of
+** the corresponding table b-tree. This makes things a bit more complicated,
+** as this module treats each b-tree as a separate structure. To determine
+** the table b-tree corresponding to the index b-tree being written, this
+** function has to search through the database schema.
+**
+** Instead of a lock on the b-tree rooted at page iRoot, the caller may
+** hold a write-lock on the schema table (root page 1). This is also
+** acceptable.
+*/
+static int hasSharedCacheTableLock(
+  Btree *pBtree,         /* Handle that must hold lock */
+  Pgno iRoot,            /* Root page of b-tree */
+  int isIndex,           /* True if iRoot is the root of an index b-tree */
+  int eLockType          /* Required lock type (READ_LOCK or WRITE_LOCK) */
+){
+  Schema *pSchema = (Schema *)pBtree->pBt->pSchema;
+  Pgno iTab = 0;
+  BtLock *pLock;
+
+  /* If this b-tree database is not shareable, or if the client is reading
+  ** and has the read-uncommitted flag set, then no lock is required. 
+  ** In these cases return true immediately.  If the client is reading 
+  ** or writing an index b-tree, but the schema is not loaded, then return
+  ** true also. In this case the lock is required, but it is too difficult
+  ** to check if the client actually holds it. This doesn't happen very
+  ** often.  */
+  if( (pBtree->sharable==0)
+   || (eLockType==READ_LOCK && (pBtree->db->flags & SQLITE_ReadUncommitted))
+   || (isIndex && (!pSchema || (pSchema->flags&DB_SchemaLoaded)==0 ))
+  ){
+    return 1;
+  }
+
+  /* Figure out the root-page that the lock should be held on. For table
+  ** b-trees, this is just the root page of the b-tree being read or
+  ** written. For index b-trees, it is the root page of the associated
+  ** table.  */
+  if( isIndex ){
+    HashElem *p;
+    for(p=sqliteHashFirst(&pSchema->idxHash); p; p=sqliteHashNext(p)){
+      Index *pIdx = (Index *)sqliteHashData(p);
+      if( pIdx->tnum==(int)iRoot ){
+        iTab = pIdx->pTable->tnum;
+      }
+    }
   }else{
-    rc = SQLITE_OK;
+    iTab = iRoot;
   }
-  pBt->inStmt = 0;
-  sqlite3BtreeLeave(p);
-  return rc;
+
+  /* Search for the required lock. Either a write-lock on root-page iTab, a 
+  ** write-lock on the schema table, or (if the client is reading) a
+  ** read-lock on iTab will suffice. Return 1 if any of these are found.  */
+  for(pLock=pBtree->pBt->pLock; pLock; pLock=pLock->pNext){
+    if( pLock->pBtree==pBtree 
+     && (pLock->iTable==iTab || (pLock->eLock==WRITE_LOCK && pLock->iTable==1))
+     && pLock->eLock>=eLockType 
+    ){
+      return 1;
+    }
+  }
+
+  /* Failed to find the required lock. */
+  return 0;
 }
 
 /*
-** Rollback the active statement subtransaction.  If no subtransaction
-** is active this routine is a no-op.
+** This function is also used as part of assert() statements only. It 
+** returns true if there exist one or more cursors open on the table 
+** with root page iRoot that do not belong to either connection pBtree 
+** or some other connection that has the read-uncommitted flag set.
 **
-** All cursors will be invalidated by this operation.  Any attempt
-** to use a cursor that was open at the beginning of this operation
-** will result in an error.
+** For example, before writing to page iRoot:
+**
+**    assert( !hasReadConflicts(pBtree, iRoot) );
 */
-SQLITE_PRIVATE int sqlite3BtreeRollbackStmt(Btree *p){
-  int rc = SQLITE_OK;
+static int hasReadConflicts(Btree *pBtree, Pgno iRoot){
+  BtCursor *p;
+  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
+    if( p->pgnoRoot==iRoot 
+     && p->pBtree!=pBtree
+     && 0==(p->pBtree->db->flags & SQLITE_ReadUncommitted)
+    ){
+      return 1;
+    }
+  }
+  return 0;
+}
+#endif    /* #ifdef SQLITE_DEBUG */
+
+/*
+** Query to see if btree handle p may obtain a lock of type eLock 
+** (READ_LOCK or WRITE_LOCK) on the table with root-page iTab. Return
+** SQLITE_OK if the lock may be obtained (by calling
+** setSharedCacheTableLock()), or SQLITE_LOCKED if not.
+*/
+static int querySharedCacheTableLock(Btree *p, Pgno iTab, u8 eLock){
   BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  if( pBt->inStmt && !pBt->readOnly ){
-    rc = sqlite3PagerStmtRollback(pBt->pPager);
-    assert( countWriteCursors(pBt)==0 );
-    pBt->inStmt = 0;
+  BtLock *pIter;
+
+  assert( sqlite3BtreeHoldsMutex(p) );
+  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
+  assert( p->db!=0 );
+  assert( !(p->db->flags&SQLITE_ReadUncommitted)||eLock==WRITE_LOCK||iTab==1 );
+  
+  /* If requesting a write-lock, then the Btree must have an open write
+  ** transaction on this file. And, obviously, for this to be so there 
+  ** must be an open write transaction on the file itself.
+  */
+  assert( eLock==READ_LOCK || (p==pBt->pWriter && p->inTrans==TRANS_WRITE) );
+  assert( eLock==READ_LOCK || pBt->inTransaction==TRANS_WRITE );
+  
+  /* This is a no-op if the shared-cache is not enabled */
+  if( !p->sharable ){
+    return SQLITE_OK;
   }
-  sqlite3BtreeLeave(p);
-  return rc;
+
+  /* If some other connection is holding an exclusive lock, the
+  ** requested lock may not be obtained.
+  */
+  if( pBt->pWriter!=p && pBt->isExclusive ){
+    sqlite3ConnectionBlocked(p->db, pBt->pWriter->db);
+    return SQLITE_LOCKED_SHAREDCACHE;
+  }
+
+  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
+    /* The condition (pIter->eLock!=eLock) in the following if(...) 
+    ** statement is a simplification of:
+    **
+    **   (eLock==WRITE_LOCK || pIter->eLock==WRITE_LOCK)
+    **
+    ** since we know that if eLock==WRITE_LOCK, then no other connection
+    ** may hold a WRITE_LOCK on any table in this file (since there can
+    ** only be a single writer).
+    */
+    assert( pIter->eLock==READ_LOCK || pIter->eLock==WRITE_LOCK );
+    assert( eLock==READ_LOCK || pIter->pBtree==p || pIter->eLock==READ_LOCK);
+    if( pIter->pBtree!=p && pIter->iTable==iTab && pIter->eLock!=eLock ){
+      sqlite3ConnectionBlocked(p->db, pIter->pBtree->db);
+      if( eLock==WRITE_LOCK ){
+        assert( p==pBt->pWriter );
+        pBt->isPending = 1;
+      }
+      return SQLITE_LOCKED_SHAREDCACHE;
+    }
+  }
+  return SQLITE_OK;
 }
+#endif /* !SQLITE_OMIT_SHARED_CACHE */
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** Create a new cursor for the BTree whose root is on the page
-** iTable.  The act of acquiring a cursor gets a read lock on 
-** the database file.
-**
-** If wrFlag==0, then the cursor can only be used for reading.
-** If wrFlag==1, then the cursor can be used for reading or for
-** writing if other conditions for writing are also met.  These
-** are the conditions that must be met in order for writing to
-** be allowed:
-**
-** 1:  The cursor must have been opened with wrFlag==1
+** Add a lock on the table with root-page iTable to the shared-btree used
+** by Btree handle p. Parameter eLock must be either READ_LOCK or 
+** WRITE_LOCK.
 **
-** 2:  Other database connections that share the same pager cache
-**     but which are not in the READ_UNCOMMITTED state may not have
-**     cursors open with wrFlag==0 on the same table.  Otherwise
-**     the changes made by this write cursor would be visible to
-**     the read cursors in the other database connection.
+** This function assumes the following:
 **
-** 3:  The database must be writable (not on read-only media)
+**   (a) The specified b-tree connection handle is connected to a sharable
+**       b-tree database (one with the BtShared.sharable) flag set, and
 **
-** 4:  There must be an active transaction.
+**   (b) No other b-tree connection handle holds a lock that conflicts
+**       with the requested lock (i.e. querySharedCacheTableLock() has
+**       already been called and returned SQLITE_OK).
 **
-** No checking is done to make sure that page iTable really is the
-** root page of a b-tree.  If it is not, then the cursor acquired
-** will not work correctly.
+** SQLITE_OK is returned if the lock is added successfully. SQLITE_NOMEM 
+** is returned if a malloc attempt fails.
 */
-static int btreeCursor(
-  Btree *p,                              /* The btree */
-  int iTable,                            /* Root page of table to open */
-  int wrFlag,                            /* 1 to write. 0 read-only */
-  struct KeyInfo *pKeyInfo,              /* First arg to comparison function */
-  BtCursor *pCur                         /* Space for new cursor */
-){
-  int rc;
+static int setSharedCacheTableLock(Btree *p, Pgno iTable, u8 eLock){
   BtShared *pBt = p->pBt;
+  BtLock *pLock = 0;
+  BtLock *pIter;
 
   assert( sqlite3BtreeHoldsMutex(p) );
-  if( wrFlag ){
-    if( pBt->readOnly ){
-      return SQLITE_READONLY;
-    }
-    if( checkReadLocks(p, iTable, 0) ){
-      return SQLITE_LOCKED;
+  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
+  assert( p->db!=0 );
+
+  /* A connection with the read-uncommitted flag set will never try to
+  ** obtain a read-lock using this function. The only read-lock obtained
+  ** by a connection in read-uncommitted mode is on the sqlite_master 
+  ** table, and that lock is obtained in BtreeBeginTrans().  */
+  assert( 0==(p->db->flags&SQLITE_ReadUncommitted) || eLock==WRITE_LOCK );
+
+  /* This function should only be called on a sharable b-tree after it 
+  ** has been determined that no other b-tree holds a conflicting lock.  */
+  assert( p->sharable );
+  assert( SQLITE_OK==querySharedCacheTableLock(p, iTable, eLock) );
+
+  /* First search the list for an existing lock on this table. */
+  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
+    if( pIter->iTable==iTable && pIter->pBtree==p ){
+      pLock = pIter;
+      break;
     }
   }
 
-  if( pBt->pPage1==0 ){
-    rc = lockBtreeWithRetry(p);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    if( pBt->readOnly && wrFlag ){
-      return SQLITE_READONLY;
+  /* If the above search did not find a BtLock struct associating Btree p
+  ** with table iTable, allocate one and link it into the list.
+  */
+  if( !pLock ){
+    pLock = (BtLock *)sqlite3MallocZero(sizeof(BtLock));
+    if( !pLock ){
+      return SQLITE_NOMEM;
     }
-  }
-  pCur->pgnoRoot = (Pgno)iTable;
-  if( iTable==1 && sqlite3PagerPagecount(pBt->pPager)==0 ){
-    rc = SQLITE_EMPTY;
-    goto create_cursor_exception;
-  }
-  rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->pPage, 0);
-  if( rc!=SQLITE_OK ){
-    goto create_cursor_exception;
+    pLock->iTable = iTable;
+    pLock->pBtree = p;
+    pLock->pNext = pBt->pLock;
+    pBt->pLock = pLock;
   }
 
-  /* Now that no other errors can occur, finish filling in the BtCursor
-  ** variables, link the cursor into the BtShared list and set *ppCur (the
-  ** output argument to this function).
+  /* Set the BtLock.eLock variable to the maximum of the current lock
+  ** and the requested lock. This means if a write-lock was already held
+  ** and a read-lock requested, we don't incorrectly downgrade the lock.
   */
-  pCur->pKeyInfo = pKeyInfo;
-  pCur->pBtree = p;
-  pCur->pBt = pBt;
-  pCur->wrFlag = wrFlag;
-  pCur->pNext = pBt->pCursor;
-  if( pCur->pNext ){
-    pCur->pNext->pPrev = pCur;
+  assert( WRITE_LOCK>READ_LOCK );
+  if( eLock>pLock->eLock ){
+    pLock->eLock = eLock;
   }
-  pBt->pCursor = pCur;
-  pCur->eState = CURSOR_INVALID;
 
   return SQLITE_OK;
+}
+#endif /* !SQLITE_OMIT_SHARED_CACHE */
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+/*
+** Release all the table locks (locks obtained via calls to
+** the setSharedCacheTableLock() procedure) held by Btree handle p.
+**
+** This function assumes that handle p has an open read or write 
+** transaction. If it does not, then the BtShared.isPending variable
+** may be incorrectly cleared.
+*/
+static void clearAllSharedCacheTableLocks(Btree *p){
+  BtShared *pBt = p->pBt;
+  BtLock **ppIter = &pBt->pLock;
 
-create_cursor_exception:
-  if( pCur ){
-    releasePage(pCur->pPage);
+  assert( sqlite3BtreeHoldsMutex(p) );
+  assert( p->sharable || 0==*ppIter );
+  assert( p->inTrans>0 );
+
+  while( *ppIter ){
+    BtLock *pLock = *ppIter;
+    assert( pBt->isExclusive==0 || pBt->pWriter==pLock->pBtree );
+    assert( pLock->pBtree->inTrans>=pLock->eLock );
+    if( pLock->pBtree==p ){
+      *ppIter = pLock->pNext;
+      assert( pLock->iTable!=1 || pLock==&p->lock );
+      if( pLock->iTable!=1 ){
+        sqlite3_free(pLock);
+      }
+    }else{
+      ppIter = &pLock->pNext;
+    }
+  }
+
+  assert( pBt->isPending==0 || pBt->pWriter );
+  if( pBt->pWriter==p ){
+    pBt->pWriter = 0;
+    pBt->isExclusive = 0;
+    pBt->isPending = 0;
+  }else if( pBt->nTransaction==2 ){
+    /* This function is called when connection p is concluding its 
+    ** transaction. If there currently exists a writer, and p is not
+    ** that writer, then the number of locks held by connections other
+    ** than the writer must be about to drop to zero. In this case
+    ** set the isPending flag to 0.
+    **
+    ** If there is not currently a writer, then BtShared.isPending must
+    ** be zero already. So this next line is harmless in that case.
+    */
+    pBt->isPending = 0;
   }
-  unlockBtreeIfUnused(pBt);
-  return rc;
-}
-SQLITE_PRIVATE int sqlite3BtreeCursor(
-  Btree *p,                                   /* The btree */
-  int iTable,                                 /* Root page of table to open */
-  int wrFlag,                                 /* 1 to write. 0 read-only */
-  struct KeyInfo *pKeyInfo,                   /* First arg to xCompare() */
-  BtCursor *pCur                              /* Write new cursor here */
-){
-  int rc;
-  sqlite3BtreeEnter(p);
-  p->pBt->db = p->db;
-  rc = btreeCursor(p, iTable, wrFlag, pKeyInfo, pCur);
-  sqlite3BtreeLeave(p);
-  return rc;
 }
-SQLITE_PRIVATE int sqlite3BtreeCursorSize(){
-  return sizeof(BtCursor);
+
+/*
+** This function changes all write-locks held by connection p to read-locks.
+*/
+static void downgradeAllSharedCacheTableLocks(Btree *p){
+  BtShared *pBt = p->pBt;
+  if( pBt->pWriter==p ){
+    BtLock *pLock;
+    pBt->pWriter = 0;
+    pBt->isExclusive = 0;
+    pBt->isPending = 0;
+    for(pLock=pBt->pLock; pLock; pLock=pLock->pNext){
+      assert( pLock->eLock==READ_LOCK || pLock->pBtree==p );
+      pLock->eLock = READ_LOCK;
+    }
+  }
 }
 
+#endif /* SQLITE_OMIT_SHARED_CACHE */
 
+static void releasePage(MemPage *pPage);  /* Forward reference */
 
 /*
-** Close a cursor.  The read lock on the database file is released
-** when the last cursor is closed.
+** Verify that the cursor holds a mutex on the BtShared
 */
-SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor *pCur){
-  Btree *pBtree = pCur->pBtree;
-  if( pBtree ){
-    BtShared *pBt = pCur->pBt;
-    sqlite3BtreeEnter(pBtree);
-    pBt->db = pBtree->db;
-    clearCursorPosition(pCur);
-    if( pCur->pPrev ){
-      pCur->pPrev->pNext = pCur->pNext;
-    }else{
-      pBt->pCursor = pCur->pNext;
-    }
-    if( pCur->pNext ){
-      pCur->pNext->pPrev = pCur->pPrev;
-    }
-    releasePage(pCur->pPage);
-    unlockBtreeIfUnused(pBt);
-    invalidateOverflowCache(pCur);
-    /* sqlite3_free(pCur); */
-    sqlite3BtreeLeave(pBtree);
-  }
-  return SQLITE_OK;
+#ifndef NDEBUG
+static int cursorHoldsMutex(BtCursor *p){
+  return sqlite3_mutex_held(p->pBt->mutex);
 }
+#endif
+
 
+#ifndef SQLITE_OMIT_INCRBLOB
 /*
-** Make a temporary cursor by filling in the fields of pTempCur.
-** The temporary cursor is not on the cursor list for the Btree.
+** Invalidate the overflow page-list cache for cursor pCur, if any.
 */
-SQLITE_PRIVATE void sqlite3BtreeGetTempCursor(BtCursor *pCur, BtCursor *pTempCur){
+static void invalidateOverflowCache(BtCursor *pCur){
   assert( cursorHoldsMutex(pCur) );
-  memcpy(pTempCur, pCur, sizeof(*pCur));
-  pTempCur->pNext = 0;
-  pTempCur->pPrev = 0;
-  if( pTempCur->pPage ){
-    sqlite3PagerRef(pTempCur->pPage->pDbPage);
-  }
+  sqlite3_free(pCur->aOverflow);
+  pCur->aOverflow = 0;
 }
 
 /*
-** Delete a temporary cursor such as was made by the CreateTemporaryCursor()
-** function above.
+** Invalidate the overflow page-list cache for all cursors opened
+** on the shared btree structure pBt.
 */
-SQLITE_PRIVATE void sqlite3BtreeReleaseTempCursor(BtCursor *pCur){
-  assert( cursorHoldsMutex(pCur) );
-  if( pCur->pPage ){
-    sqlite3PagerUnref(pCur->pPage->pDbPage);
+static void invalidateAllOverflowCache(BtShared *pBt){
+  BtCursor *p;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  for(p=pBt->pCursor; p; p=p->pNext){
+    invalidateOverflowCache(p);
   }
 }
 
 /*
-** Make sure the BtCursor* given in the argument has a valid
-** BtCursor.info structure.  If it is not already valid, call
-** sqlite3BtreeParseCell() to fill it in.
+** This function is called before modifying the contents of a table
+** b-tree to invalidate any incrblob cursors that are open on the
+** row or one of the rows being modified.
 **
-** BtCursor.info is a cache of the information in the current cell.
-** Using this cache reduces the number of calls to sqlite3BtreeParseCell().
+** If argument isClearTable is true, then the entire contents of the
+** table is about to be deleted. In this case invalidate all incrblob
+** cursors open on any row within the table with root-page pgnoRoot.
 **
-** 2007-06-25:  There is a bug in some versions of MSVC that cause the
-** compiler to crash when getCellInfo() is implemented as a macro.
-** But there is a measureable speed advantage to using the macro on gcc
-** (when less compiler optimizations like -Os or -O0 are used and the
-** compiler is not doing agressive inlining.)  So we use a real function
-** for MSVC and a macro for everything else.  Ticket #2457.
+** Otherwise, if argument isClearTable is false, then the row with
+** rowid iRow is being replaced or deleted. In this case invalidate
+** only those incrblob cursors open on this specific row.
 */
-#ifndef NDEBUG
-  static void assertCellInfo(BtCursor *pCur){
-    CellInfo info;
-    memset(&info, 0, sizeof(info));
-    sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &info);
-    assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
+static void invalidateIncrblobCursors(
+  Btree *pBtree,          /* The database file to check */
+  i64 iRow,               /* The rowid that might be changing */
+  int isClearTable        /* True if all rows are being deleted */
+){
+  BtCursor *p;
+  BtShared *pBt = pBtree->pBt;
+  assert( sqlite3BtreeHoldsMutex(pBtree) );
+  for(p=pBt->pCursor; p; p=p->pNext){
+    if( p->isIncrblobHandle && (isClearTable || p->info.nKey==iRow) ){
+      p->eState = CURSOR_INVALID;
+    }
   }
+}
+
 #else
-  #define assertCellInfo(x)
+  #define invalidateOverflowCache(x)
+  #define invalidateAllOverflowCache(x)
+  #define invalidateIncrblobCursors(x,y,z)
 #endif
-#ifdef _MSC_VER
-  /* Use a real function in MSVC to work around bugs in that compiler. */
-  static void getCellInfo(BtCursor *pCur){
-    if( pCur->info.nSize==0 ){
-      sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &pCur->info);
-      pCur->validNKey = 1;
-    }else{
-      assertCellInfo(pCur);
-    }
-  }
-#else /* if not _MSC_VER */
-  /* Use a macro in all other compilers so that the function is inlined */
-#define getCellInfo(pCur)                                               \
-  if( pCur->info.nSize==0 ){                                            \
-    sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &pCur->info);         \
-    pCur->validNKey = 1;                                                \
-  }else{                                                                \
-    assertCellInfo(pCur);                                               \
-  }
-#endif /* _MSC_VER */
 
 /*
-** Set *pSize to the size of the buffer needed to hold the value of
-** the key for the current entry.  If the cursor is not pointing
-** to a valid entry, *pSize is set to 0. 
+** Set bit pgno of the BtShared.pHasContent bitvec. This is called 
+** when a page that previously contained data becomes a free-list leaf 
+** page.
 **
-** For a table with the INTKEY flag set, this routine returns the key
-** itself, not the number of bytes in the key.
-*/
-SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){
-  int rc;
-
-  assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
-  if( rc==SQLITE_OK ){
-    assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
-    if( pCur->eState==CURSOR_INVALID ){
-      *pSize = 0;
-    }else{
-      getCellInfo(pCur);
-      *pSize = pCur->info.nKey;
+** The BtShared.pHasContent bitvec exists to work around an obscure
+** bug caused by the interaction of two useful IO optimizations surrounding
+** free-list leaf pages:
+**
+**   1) When all data is deleted from a page and the page becomes
+**      a free-list leaf page, the page is not written to the database
+**      (as free-list leaf pages contain no meaningful data). Sometimes
+**      such a page is not even journalled (as it will not be modified,
+**      why bother journalling it?).
+**
+**   2) When a free-list leaf page is reused, its content is not read
+**      from the database or written to the journal file (why should it
+**      be, if it is not at all meaningful?).
+**
+** By themselves, these optimizations work fine and provide a handy
+** performance boost to bulk delete or insert operations. However, if
+** a page is moved to the free-list and then reused within the same
+** transaction, a problem comes up. If the page is not journalled when
+** it is moved to the free-list and it is also not journalled when it
+** is extracted from the free-list and reused, then the original data
+** may be lost. In the event of a rollback, it may not be possible
+** to restore the database to its original configuration.
+**
+** The solution is the BtShared.pHasContent bitvec. Whenever a page is 
+** moved to become a free-list leaf page, the corresponding bit is
+** set in the bitvec. Whenever a leaf page is extracted from the free-list,
+** optimization 2 above is ommitted if the corresponding bit is already
+** set in BtShared.pHasContent. The contents of the bitvec are cleared
+** at the end of every transaction.
+*/
+static int btreeSetHasContent(BtShared *pBt, Pgno pgno){
+  int rc = SQLITE_OK;
+  if( !pBt->pHasContent ){
+    int nPage = 100;
+    sqlite3PagerPagecount(pBt->pPager, &nPage);
+    /* If sqlite3PagerPagecount() fails there is no harm because the
+    ** nPage variable is unchanged from its default value of 100 */
+    pBt->pHasContent = sqlite3BitvecCreate((u32)nPage);
+    if( !pBt->pHasContent ){
+      rc = SQLITE_NOMEM;
     }
   }
+  if( rc==SQLITE_OK && pgno<=sqlite3BitvecSize(pBt->pHasContent) ){
+    rc = sqlite3BitvecSet(pBt->pHasContent, pgno);
+  }
   return rc;
 }
 
 /*
-** Set *pSize to the number of bytes of data in the entry the
-** cursor currently points to.  Always return SQLITE_OK.
-** Failure is not possible.  If the cursor is not currently
-** pointing to an entry (which can happen, for example, if
-** the database is empty) then *pSize is set to 0.
+** Query the BtShared.pHasContent vector.
+**
+** This function is called when a free-list leaf page is removed from the
+** free-list for reuse. It returns false if it is safe to retrieve the
+** page from the pager layer with the 'no-content' flag set. True otherwise.
 */
-SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
-  int rc;
+static int btreeGetHasContent(BtShared *pBt, Pgno pgno){
+  Bitvec *p = pBt->pHasContent;
+  return (p && (pgno>sqlite3BitvecSize(p) || sqlite3BitvecTest(p, pgno)));
+}
 
-  assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
-  if( rc==SQLITE_OK ){
-    assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
-    if( pCur->eState==CURSOR_INVALID ){
-      /* Not pointing at a valid entry - set *pSize to 0. */
-      *pSize = 0;
-    }else{
-      getCellInfo(pCur);
-      *pSize = pCur->info.nData;
-    }
-  }
-  return rc;
+/*
+** Clear (destroy) the BtShared.pHasContent bitvec. This should be
+** invoked at the conclusion of each write-transaction.
+*/
+static void btreeClearHasContent(BtShared *pBt){
+  sqlite3BitvecDestroy(pBt->pHasContent);
+  pBt->pHasContent = 0;
 }
 
 /*
-** Given the page number of an overflow page in the database (parameter
-** ovfl), this function finds the page number of the next page in the 
-** linked list of overflow pages. If possible, it uses the auto-vacuum
-** pointer-map data instead of reading the content of page ovfl to do so. 
-**
-** If an error occurs an SQLite error code is returned. Otherwise:
-**
-** Unless pPgnoNext is NULL, the page number of the next overflow 
-** page in the linked list is written to *pPgnoNext. If page ovfl
-** is the last page in its linked list, *pPgnoNext is set to zero. 
+** Save the current cursor position in the variables BtCursor.nKey 
+** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK.
 **
-** If ppPage is not NULL, *ppPage is set to the MemPage* handle
-** for page ovfl. The underlying pager page may have been requested
-** with the noContent flag set, so the page data accessable via
-** this handle may not be trusted.
+** The caller must ensure that the cursor is valid (has eState==CURSOR_VALID)
+** prior to calling this routine.  
 */
-static int getOverflowPage(
-  BtShared *pBt, 
-  Pgno ovfl,                   /* Overflow page */
-  MemPage **ppPage,            /* OUT: MemPage handle */
-  Pgno *pPgnoNext              /* OUT: Next overflow page number */
-){
-  Pgno next = 0;
+static int saveCursorPosition(BtCursor *pCur){
   int rc;
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  /* One of these must not be NULL. Otherwise, why call this function? */
-  assert(ppPage || pPgnoNext);
+  assert( CURSOR_VALID==pCur->eState );
+  assert( 0==pCur->pKey );
+  assert( cursorHoldsMutex(pCur) );
 
-  /* If pPgnoNext is NULL, then this function is being called to obtain
-  ** a MemPage* reference only. No page-data is required in this case.
-  */
-  if( !pPgnoNext ){
-    return sqlite3BtreeGetPage(pBt, ovfl, ppPage, 1);
-  }
+  rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
+  assert( rc==SQLITE_OK );  /* KeySize() cannot fail */
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  /* Try to find the next page in the overflow list using the
-  ** autovacuum pointer-map pages. Guess that the next page in 
-  ** the overflow list is page number (ovfl+1). If that guess turns 
-  ** out to be wrong, fall back to loading the data of page 
-  ** number ovfl to determine the next page number.
+  /* If this is an intKey table, then the above call to BtreeKeySize()
+  ** stores the integer key in pCur->nKey. In this case this value is
+  ** all that is required. Otherwise, if pCur is not open on an intKey
+  ** table, then malloc space for and store the pCur->nKey bytes of key 
+  ** data.
   */
-  if( pBt->autoVacuum ){
-    Pgno pgno;
-    Pgno iGuess = ovfl+1;
-    u8 eType;
-
-    while( PTRMAP_ISPAGE(pBt, iGuess) || iGuess==PENDING_BYTE_PAGE(pBt) ){
-      iGuess++;
-    }
-
-    if( iGuess<=sqlite3PagerPagecount(pBt->pPager) ){
-      rc = ptrmapGet(pBt, iGuess, &eType, &pgno);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-      if( eType==PTRMAP_OVERFLOW2 && pgno==ovfl ){
-        next = iGuess;
+  if( 0==pCur->apPage[0]->intKey ){
+    void *pKey = sqlite3Malloc( (int)pCur->nKey );
+    if( pKey ){
+      rc = sqlite3BtreeKey(pCur, 0, (int)pCur->nKey, pKey);
+      if( rc==SQLITE_OK ){
+        pCur->pKey = pKey;
+      }else{
+        sqlite3_free(pKey);
       }
+    }else{
+      rc = SQLITE_NOMEM;
     }
   }
-#endif
-
-  if( next==0 || ppPage ){
-    MemPage *pPage = 0;
-
-    rc = sqlite3BtreeGetPage(pBt, ovfl, &pPage, next!=0);
-    assert(rc==SQLITE_OK || pPage==0);
-    if( next==0 && rc==SQLITE_OK ){
-      next = get4byte(pPage->aData);
-    }
+  assert( !pCur->apPage[0]->intKey || !pCur->pKey );
 
-    if( ppPage ){
-      *ppPage = pPage;
-    }else{
-      releasePage(pPage);
+  if( rc==SQLITE_OK ){
+    int i;
+    for(i=0; i<=pCur->iPage; i++){
+      releasePage(pCur->apPage[i]);
+      pCur->apPage[i] = 0;
     }
+    pCur->iPage = -1;
+    pCur->eState = CURSOR_REQUIRESEEK;
   }
-  *pPgnoNext = next;
 
+  invalidateOverflowCache(pCur);
   return rc;
 }
 
 /*
-** Copy data from a buffer to a page, or from a page to a buffer.
-**
-** pPayload is a pointer to data stored on database page pDbPage.
-** If argument eOp is false, then nByte bytes of data are copied
-** from pPayload to the buffer pointed at by pBuf. If eOp is true,
-** then sqlite3PagerWrite() is called on pDbPage and nByte bytes
-** of data are copied from the buffer pBuf to pPayload.
-**
-** SQLITE_OK is returned on success, otherwise an error code.
+** Save the positions of all cursors except pExcept open on the table 
+** with root-page iRoot. Usually, this is called just before cursor
+** pExcept is used to modify the table (BtreeDelete() or BtreeInsert()).
 */
-static int copyPayload(
-  void *pPayload,           /* Pointer to page data */
-  void *pBuf,               /* Pointer to buffer */
-  int nByte,                /* Number of bytes to copy */
-  int eOp,                  /* 0 -> copy from page, 1 -> copy to page */
-  DbPage *pDbPage           /* Page containing pPayload */
-){
-  if( eOp ){
-    /* Copy data from buffer to page (a write operation) */
-    int rc = sqlite3PagerWrite(pDbPage);
-    if( rc!=SQLITE_OK ){
-      return rc;
+static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
+  BtCursor *p;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( pExcept==0 || pExcept->pBt==pBt );
+  for(p=pBt->pCursor; p; p=p->pNext){
+    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) && 
+        p->eState==CURSOR_VALID ){
+      int rc = saveCursorPosition(p);
+      if( SQLITE_OK!=rc ){
+        return rc;
+      }
     }
-    memcpy(pPayload, pBuf, nByte);
-  }else{
-    /* Copy data from page to buffer (a read operation) */
-    memcpy(pBuf, pPayload, nByte);
   }
   return SQLITE_OK;
 }
 
 /*
-** This function is used to read or overwrite payload information
-** for the entry that the pCur cursor is pointing to. If the eOp
-** parameter is 0, this is a read operation (data copied into
-** buffer pBuf). If it is non-zero, a write (data copied from
-** buffer pBuf).
-**
-** A total of "amt" bytes are read or written beginning at "offset".
-** Data is read to or from the buffer pBuf.
-**
-** This routine does not make a distinction between key and data.
-** It just reads or writes bytes from the payload area.  Data might 
-** appear on the main page or be scattered out on multiple overflow 
-** pages.
-**
-** If the BtCursor.isIncrblobHandle flag is set, and the current
-** cursor entry uses one or more overflow pages, this function
-** allocates space for and lazily popluates the overflow page-list 
-** cache array (BtCursor.aOverflow). Subsequent calls use this
-** cache to make seeking to the supplied offset more efficient.
-**
-** Once an overflow page-list cache has been allocated, it may be
-** invalidated if some other cursor writes to the same table, or if
-** the cursor is moved to a different row. Additionally, in auto-vacuum
-** mode, the following events may invalidate an overflow page-list cache.
-**
-**   * An incremental vacuum,
-**   * A commit in auto_vacuum="full" mode,
-**   * Creating a table (may require moving an overflow page).
+** Clear the current cursor position.
 */
-static int accessPayload(
-  BtCursor *pCur,      /* Cursor pointing to entry to read from */
-  int offset,          /* Begin reading this far into payload */
-  int amt,             /* Read this many bytes */
-  unsigned char *pBuf, /* Write the bytes into this buffer */ 
-  int skipKey,         /* offset begins at data if this is true */
-  int eOp              /* zero to read. non-zero to write. */
-){
-  unsigned char *aPayload;
-  int rc = SQLITE_OK;
-  u32 nKey;
-  int iIdx = 0;
-  MemPage *pPage = pCur->pPage;     /* Btree page of current cursor entry */
-  BtShared *pBt;                   /* Btree this cursor belongs to */
-
-  assert( pPage );
-  assert( pCur->eState==CURSOR_VALID );
-  assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
-  assert( offset>=0 );
+SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *pCur){
   assert( cursorHoldsMutex(pCur) );
+  sqlite3_free(pCur->pKey);
+  pCur->pKey = 0;
+  pCur->eState = CURSOR_INVALID;
+}
 
-  getCellInfo(pCur);
-  aPayload = pCur->info.pCell + pCur->info.nHeader;
-  nKey = (pPage->intKey ? 0 : pCur->info.nKey);
-
-  if( skipKey ){
-    offset += nKey;
-  }
-  if( offset+amt > nKey+pCur->info.nData ){
-    /* Trying to read or write past the end of the data is an error */
-    return SQLITE_ERROR;
-  }
+/*
+** In this version of BtreeMoveto, pKey is a packed index record
+** such as is generated by the OP_MakeRecord opcode.  Unpack the
+** record and then call BtreeMovetoUnpacked() to do the work.
+*/
+static int btreeMoveto(
+  BtCursor *pCur,     /* Cursor open on the btree to be searched */
+  const void *pKey,   /* Packed key if the btree is an index */
+  i64 nKey,           /* Integer key for tables.  Size of pKey for indices */
+  int bias,           /* Bias search to the high end */
+  int *pRes           /* Write search results here */
+){
+  int rc;                    /* Status code */
+  UnpackedRecord *pIdxKey;   /* Unpacked index key */
+  char aSpace[150];          /* Temp space for pIdxKey - to avoid a malloc */
 
-  /* Check if data must be read/written to/from the btree page itself. */
-  if( offset<pCur->info.nLocal ){
-    int a = amt;
-    if( a+offset>pCur->info.nLocal ){
-      a = pCur->info.nLocal - offset;
-    }
-    rc = copyPayload(&aPayload[offset], pBuf, a, eOp, pPage->pDbPage);
-    offset = 0;
-    pBuf += a;
-    amt -= a;
+  if( pKey ){
+    assert( nKey==(i64)(int)nKey );
+    pIdxKey = sqlite3VdbeRecordUnpack(pCur->pKeyInfo, (int)nKey, pKey,
+                                      aSpace, sizeof(aSpace));
+    if( pIdxKey==0 ) return SQLITE_NOMEM;
   }else{
-    offset -= pCur->info.nLocal;
-  }
-
-  pBt = pCur->pBt;
-  if( rc==SQLITE_OK && amt>0 ){
-    const int ovflSize = pBt->usableSize - 4;  /* Bytes content per ovfl page */
-    Pgno nextPage;
-
-    nextPage = get4byte(&aPayload[pCur->info.nLocal]);
-
-#ifndef SQLITE_OMIT_INCRBLOB
-    /* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
-    ** has not been allocated, allocate it now. The array is sized at
-    ** one entry for each overflow page in the overflow chain. The
-    ** page number of the first overflow page is stored in aOverflow[0],
-    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
-    ** (the cache is lazily populated).
-    */
-    if( pCur->isIncrblobHandle && !pCur->aOverflow ){
-      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
-      pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
-      if( nOvfl && !pCur->aOverflow ){
-        rc = SQLITE_NOMEM;
-      }
-    }
-
-    /* If the overflow page-list cache has been allocated and the
-    ** entry for the first required overflow page is valid, skip
-    ** directly to it.
-    */
-    if( pCur->aOverflow && pCur->aOverflow[offset/ovflSize] ){
-      iIdx = (offset/ovflSize);
-      nextPage = pCur->aOverflow[iIdx];
-      offset = (offset%ovflSize);
-    }
-#endif
-
-    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){
-
-#ifndef SQLITE_OMIT_INCRBLOB
-      /* If required, populate the overflow page-list cache. */
-      if( pCur->aOverflow ){
-        assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
-        pCur->aOverflow[iIdx] = nextPage;
-      }
-#endif
-
-      if( offset>=ovflSize ){
-        /* The only reason to read this page is to obtain the page
-        ** number for the next page in the overflow chain. The page
-        ** data is not required. So first try to lookup the overflow
-        ** page-list cache, if any, then fall back to the getOverflowPage()
-        ** function.
-        */
-#ifndef SQLITE_OMIT_INCRBLOB
-        if( pCur->aOverflow && pCur->aOverflow[iIdx+1] ){
-          nextPage = pCur->aOverflow[iIdx+1];
-        } else 
-#endif
-          rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
-        offset -= ovflSize;
-      }else{
-        /* Need to read this page properly. It contains some of the
-        ** range of data that is being read (eOp==0) or written (eOp!=0).
-        */
-        DbPage *pDbPage;
-        int a = amt;
-        rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage);
-        if( rc==SQLITE_OK ){
-          aPayload = sqlite3PagerGetData(pDbPage);
-          nextPage = get4byte(aPayload);
-          if( a + offset > ovflSize ){
-            a = ovflSize - offset;
-          }
-          rc = copyPayload(&aPayload[offset+4], pBuf, a, eOp, pDbPage);
-          sqlite3PagerUnref(pDbPage);
-          offset = 0;
-          amt -= a;
-          pBuf += a;
-        }
-      }
-    }
+    pIdxKey = 0;
   }
-
-  if( rc==SQLITE_OK && amt>0 ){
-    return SQLITE_CORRUPT_BKPT;
+  rc = sqlite3BtreeMovetoUnpacked(pCur, pIdxKey, nKey, bias, pRes);
+  if( pKey ){
+    sqlite3VdbeDeleteUnpackedRecord(pIdxKey);
   }
   return rc;
 }
 
 /*
-** Read part of the key associated with cursor pCur.  Exactly
-** "amt" bytes will be transfered into pBuf[].  The transfer
-** begins at "offset".
-**
-** Return SQLITE_OK on success or an error code if anything goes
-** wrong.  An error is returned if "offset+amt" is larger than
-** the available payload.
+** Restore the cursor to the position it was in (or as close to as possible)
+** when saveCursorPosition() was called. Note that this call deletes the 
+** saved position info stored by saveCursorPosition(), so there can be
+** at most one effective restoreCursorPosition() call after each 
+** saveCursorPosition().
 */
-SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
+static int btreeRestoreCursorPosition(BtCursor *pCur){
   int rc;
-
   assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
+  assert( pCur->eState>=CURSOR_REQUIRESEEK );
+  if( pCur->eState==CURSOR_FAULT ){
+    return pCur->skipNext;
+  }
+  pCur->eState = CURSOR_INVALID;
+  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skipNext);
   if( rc==SQLITE_OK ){
-    assert( pCur->eState==CURSOR_VALID );
-    assert( pCur->pPage!=0 );
-    if( pCur->pPage->intKey ){
-      return SQLITE_CORRUPT_BKPT;
-    }
-    assert( pCur->pPage->intKey==0 );
-    assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
-    rc = accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0, 0);
+    sqlite3_free(pCur->pKey);
+    pCur->pKey = 0;
+    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
   }
   return rc;
 }
 
+#define restoreCursorPosition(p) \
+  (p->eState>=CURSOR_REQUIRESEEK ? \
+         btreeRestoreCursorPosition(p) : \
+         SQLITE_OK)
+
 /*
-** Read part of the data associated with cursor pCur.  Exactly
-** "amt" bytes will be transfered into pBuf[].  The transfer
-** begins at "offset".
+** Determine whether or not a cursor has moved from the position it
+** was last placed at.  Cursors can move when the row they are pointing
+** at is deleted out from under them.
 **
-** Return SQLITE_OK on success or an error code if anything goes
-** wrong.  An error is returned if "offset+amt" is larger than
-** the available payload.
+** This routine returns an error code if something goes wrong.  The
+** integer *pHasMoved is set to one if the cursor has moved and 0 if not.
 */
-SQLITE_PRIVATE int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
+SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
   int rc;
 
-  assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
-  if( rc==SQLITE_OK ){
-    assert( pCur->eState==CURSOR_VALID );
-    assert( pCur->pPage!=0 );
-    assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
-    rc = accessPayload(pCur, offset, amt, pBuf, 1, 0);
+  rc = restoreCursorPosition(pCur);
+  if( rc ){
+    *pHasMoved = 1;
+    return rc;
   }
-  return rc;
+  if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
+    *pHasMoved = 1;
+  }else{
+    *pHasMoved = 0;
+  }
+  return SQLITE_OK;
 }
 
+#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Return a pointer to payload information from the entry that the 
-** pCur cursor is pointing to.  The pointer is to the beginning of
-** the key if skipKey==0 and it points to the beginning of data if
-** skipKey==1.  The number of bytes of available key/data is written
-** into *pAmt.  If *pAmt==0, then the value returned will not be
-** a valid pointer.
-**
-** This routine is an optimization.  It is common for the entire key
-** and data to fit on the local page and for there to be no overflow
-** pages.  When that is so, this routine can be used to access the
-** key and data without making a copy.  If the key and/or data spills
-** onto overflow pages, then accessPayload() must be used to reassembly
-** the key/data and copy it into a preallocated buffer.
-**
-** The pointer returned by this routine looks directly into the cached
-** page of the database.  The data might change or move the next time
-** any btree routine is called.
+** Given a page number of a regular database page, return the page
+** number for the pointer-map page that contains the entry for the
+** input page number.
 */
-static const unsigned char *fetchPayload(
-  BtCursor *pCur,      /* Cursor pointing to entry to read from */
-  int *pAmt,           /* Write the number of available bytes here */
-  int skipKey          /* read beginning at data if this is true */
-){
-  unsigned char *aPayload;
-  MemPage *pPage;
-  u32 nKey;
-  int nLocal;
-
-  assert( pCur!=0 && pCur->pPage!=0 );
-  assert( pCur->eState==CURSOR_VALID );
-  assert( cursorHoldsMutex(pCur) );
-  pPage = pCur->pPage;
-  assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
-  getCellInfo(pCur);
-  aPayload = pCur->info.pCell;
-  aPayload += pCur->info.nHeader;
-  if( pPage->intKey ){
-    nKey = 0;
-  }else{
-    nKey = pCur->info.nKey;
-  }
-  if( skipKey ){
-    aPayload += nKey;
-    nLocal = pCur->info.nLocal - nKey;
-  }else{
-    nLocal = pCur->info.nLocal;
-    if( nLocal>nKey ){
-      nLocal = nKey;
-    }
+static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
+  int nPagesPerMapPage;
+  Pgno iPtrMap, ret;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  nPagesPerMapPage = (pBt->usableSize/5)+1;
+  iPtrMap = (pgno-2)/nPagesPerMapPage;
+  ret = (iPtrMap*nPagesPerMapPage) + 2; 
+  if( ret==PENDING_BYTE_PAGE(pBt) ){
+    ret++;
   }
-  *pAmt = nLocal;
-  return aPayload;
+  return ret;
 }
 
-
 /*
-** For the entry that cursor pCur is point to, return as
-** many bytes of the key or data as are available on the local
-** b-tree page.  Write the number of available bytes into *pAmt.
+** Write an entry into the pointer map.
 **
-** The pointer returned is ephemeral.  The key/data may move
-** or be destroyed on the next call to any Btree routine,
-** including calls from other threads against the same cache.
-** Hence, a mutex on the BtShared should be held prior to calling
-** this routine.
+** This routine updates the pointer map entry for page number 'key'
+** so that it maps to type 'eType' and parent page number 'pgno'.
 **
-** These routines is used to get quick access to key and data
-** in the common case where no overflow pages are used.
+** If *pRC is initially non-zero (non-SQLITE_OK) then this routine is
+** a no-op.  If an error occurs, the appropriate error code is written
+** into *pRC.
 */
-SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor *pCur, int *pAmt){
-  assert( cursorHoldsMutex(pCur) );
-  if( pCur->eState==CURSOR_VALID ){
-    return (const void*)fetchPayload(pCur, pAmt, 0);
+static void ptrmapPut(BtShared *pBt, Pgno key, u8 eType, Pgno parent, int *pRC){
+  DbPage *pDbPage;  /* The pointer map page */
+  u8 *pPtrmap;      /* The pointer map data */
+  Pgno iPtrmap;     /* The pointer map page number */
+  int offset;       /* Offset in pointer map page */
+  int rc;           /* Return code from subfunctions */
+
+  if( *pRC ) return;
+
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  /* The master-journal page number must never be used as a pointer map page */
+  assert( 0==PTRMAP_ISPAGE(pBt, PENDING_BYTE_PAGE(pBt)) );
+
+  assert( pBt->autoVacuum );
+  if( key==0 ){
+    *pRC = SQLITE_CORRUPT_BKPT;
+    return;
   }
-  return 0;
-}
-SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor *pCur, int *pAmt){
-  assert( cursorHoldsMutex(pCur) );
-  if( pCur->eState==CURSOR_VALID ){
-    return (const void*)fetchPayload(pCur, pAmt, 1);
+  iPtrmap = PTRMAP_PAGENO(pBt, key);
+  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
+  if( rc!=SQLITE_OK ){
+    *pRC = rc;
+    return;
+  }
+  offset = PTRMAP_PTROFFSET(iPtrmap, key);
+  if( offset<0 ){
+    *pRC = SQLITE_CORRUPT_BKPT;
+    goto ptrmap_exit;
+  }
+  pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
+
+  if( eType!=pPtrmap[offset] || get4byte(&pPtrmap[offset+1])!=parent ){
+    TRACE(("PTRMAP_UPDATE: %d->(%d,%d)\n", key, eType, parent));
+    *pRC= rc = sqlite3PagerWrite(pDbPage);
+    if( rc==SQLITE_OK ){
+      pPtrmap[offset] = eType;
+      put4byte(&pPtrmap[offset+1], parent);
+    }
   }
-  return 0;
-}
 
+ptrmap_exit:
+  sqlite3PagerUnref(pDbPage);
+}
 
 /*
-** Move the cursor down to a new child page.  The newPgno argument is the
-** page number of the child page to move to.
+** Read an entry from the pointer map.
+**
+** This routine retrieves the pointer map entry for page 'key', writing
+** the type and parent page number to *pEType and *pPgno respectively.
+** An error code is returned if something goes wrong, otherwise SQLITE_OK.
 */
-static int moveToChild(BtCursor *pCur, u32 newPgno){
+static int ptrmapGet(BtShared *pBt, Pgno key, u8 *pEType, Pgno *pPgno){
+  DbPage *pDbPage;   /* The pointer map page */
+  int iPtrmap;       /* Pointer map page index */
+  u8 *pPtrmap;       /* Pointer map page data */
+  int offset;        /* Offset of entry in pointer map */
   int rc;
-  MemPage *pNewPage;
-  MemPage *pOldPage;
-  BtShared *pBt = pCur->pBt;
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( pCur->eState==CURSOR_VALID );
-  rc = getAndInitPage(pBt, newPgno, &pNewPage, pCur->pPage);
-  if( rc ) return rc;
-  pNewPage->idxParent = pCur->idx;
-  pOldPage = pCur->pPage;
-  pOldPage->idxShift = 0;
-  releasePage(pOldPage);
-  pCur->pPage = pNewPage;
-  pCur->idx = 0;
-  pCur->info.nSize = 0;
-  pCur->validNKey = 0;
-  if( pNewPage->nCell<1 ){
-    return SQLITE_CORRUPT_BKPT;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+
+  iPtrmap = PTRMAP_PAGENO(pBt, key);
+  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
+  if( rc!=0 ){
+    return rc;
   }
+  pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
+
+  offset = PTRMAP_PTROFFSET(iPtrmap, key);
+  assert( pEType!=0 );
+  *pEType = pPtrmap[offset];
+  if( pPgno ) *pPgno = get4byte(&pPtrmap[offset+1]);
+
+  sqlite3PagerUnref(pDbPage);
+  if( *pEType<1 || *pEType>5 ) return SQLITE_CORRUPT_BKPT;
   return SQLITE_OK;
 }
 
+#else /* if defined SQLITE_OMIT_AUTOVACUUM */
+  #define ptrmapPut(w,x,y,z,rc)
+  #define ptrmapGet(w,x,y,z) SQLITE_OK
+  #define ptrmapPutOvflPtr(x, y, rc)
+#endif
+
 /*
-** Return true if the page is the virtual root of its table.
+** Given a btree page and a cell index (0 means the first cell on
+** the page, 1 means the second cell, and so forth) return a pointer
+** to the cell content.
 **
-** The virtual root page is the root page for most tables.  But
-** for the table rooted on page 1, sometime the real root page
-** is empty except for the right-pointer.  In such cases the
-** virtual root page is the page that the right-pointer of page
-** 1 is pointing to.
+** This routine works only for pages that do not contain overflow cells.
 */
-SQLITE_PRIVATE int sqlite3BtreeIsRootPage(MemPage *pPage){
-  MemPage *pParent;
+#define findCell(P,I) \
+  ((P)->aData + ((P)->maskPage & get2byte(&(P)->aData[(P)->cellOffset+2*(I)])))
 
+/*
+** This a more complex version of findCell() that works for
+** pages that do contain overflow cells.
+*/
+static u8 *findOverflowCell(MemPage *pPage, int iCell){
+  int i;
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  pParent = pPage->pParent;
-  if( pParent==0 ) return 1;
-  if( pParent->pgno>1 ) return 0;
-  if( get2byte(&pParent->aData[pParent->hdrOffset+3])==0 ) return 1;
-  return 0;
+  for(i=pPage->nOverflow-1; i>=0; i--){
+    int k;
+    struct _OvflCell *pOvfl;
+    pOvfl = &pPage->aOvfl[i];
+    k = pOvfl->idx;
+    if( k<=iCell ){
+      if( k==iCell ){
+        return pOvfl->pCell;
+      }
+      iCell--;
+    }
+  }
+  return findCell(pPage, iCell);
 }
 
 /*
-** Move the cursor up to the parent page.
+** Parse a cell content block and fill in the CellInfo structure.  There
+** are two versions of this function.  btreeParseCell() takes a 
+** cell index as the second argument and btreeParseCellPtr() 
+** takes a pointer to the body of the cell as its second argument.
 **
-** pCur->idx is set to the cell index that contains the pointer
-** to the page we are coming from.  If we are coming from the
-** right-most child page then pCur->idx is set to one more than
-** the largest cell index.
+** Within this file, the parseCell() macro can be called instead of
+** btreeParseCellPtr(). Using some compilers, this will be faster.
 */
-SQLITE_PRIVATE void sqlite3BtreeMoveToParent(BtCursor *pCur){
-  MemPage *pParent;
-  MemPage *pPage;
-  int idxParent;
+static void btreeParseCellPtr(
+  MemPage *pPage,         /* Page containing the cell */
+  u8 *pCell,              /* Pointer to the cell text. */
+  CellInfo *pInfo         /* Fill in this structure */
+){
+  u16 n;                  /* Number bytes in cell content header */
+  u32 nPayload;           /* Number of bytes of cell payload */
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( pCur->eState==CURSOR_VALID );
-  pPage = pCur->pPage;
-  assert( pPage!=0 );
-  assert( !sqlite3BtreeIsRootPage(pPage) );
-  pParent = pPage->pParent;
-  assert( pParent!=0 );
-  idxParent = pPage->idxParent;
-  sqlite3PagerRef(pParent->pDbPage);
-  releasePage(pPage);
-  pCur->pPage = pParent;
-  pCur->info.nSize = 0;
-  pCur->validNKey = 0;
-  assert( pParent->idxShift==0 );
-  pCur->idx = idxParent;
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+
+  pInfo->pCell = pCell;
+  assert( pPage->leaf==0 || pPage->leaf==1 );
+  n = pPage->childPtrSize;
+  assert( n==4-4*pPage->leaf );
+  if( pPage->intKey ){
+    if( pPage->hasData ){
+      n += getVarint32(&pCell[n], nPayload);
+    }else{
+      nPayload = 0;
+    }
+    n += getVarint(&pCell[n], (u64*)&pInfo->nKey);
+    pInfo->nData = nPayload;
+  }else{
+    pInfo->nData = 0;
+    n += getVarint32(&pCell[n], nPayload);
+    pInfo->nKey = nPayload;
+  }
+  pInfo->nPayload = nPayload;
+  pInfo->nHeader = n;
+  testcase( nPayload==pPage->maxLocal );
+  testcase( nPayload==pPage->maxLocal+1 );
+  if( likely(nPayload<=pPage->maxLocal) ){
+    /* This is the (easy) common case where the entire payload fits
+    ** on the local page.  No overflow is required.
+    */
+    int nSize;          /* Total size of cell content in bytes */
+    nSize = nPayload + n;
+    pInfo->nLocal = (u16)nPayload;
+    pInfo->iOverflow = 0;
+    if( (nSize & ~3)==0 ){
+      nSize = 4;        /* Minimum cell size is 4 */
+    }
+    pInfo->nSize = (u16)nSize;
+  }else{
+    /* If the payload will not fit completely on the local page, we have
+    ** to decide how much to store locally and how much to spill onto
+    ** overflow pages.  The strategy is to minimize the amount of unused
+    ** space on overflow pages while keeping the amount of local storage
+    ** in between minLocal and maxLocal.
+    **
+    ** Warning:  changing the way overflow payload is distributed in any
+    ** way will result in an incompatible file format.
+    */
+    int minLocal;  /* Minimum amount of payload held locally */
+    int maxLocal;  /* Maximum amount of payload held locally */
+    int surplus;   /* Overflow payload available for local storage */
+
+    minLocal = pPage->minLocal;
+    maxLocal = pPage->maxLocal;
+    surplus = minLocal + (nPayload - minLocal)%(pPage->pBt->usableSize - 4);
+    testcase( surplus==maxLocal );
+    testcase( surplus==maxLocal+1 );
+    if( surplus <= maxLocal ){
+      pInfo->nLocal = (u16)surplus;
+    }else{
+      pInfo->nLocal = (u16)minLocal;
+    }
+    pInfo->iOverflow = (u16)(pInfo->nLocal + n);
+    pInfo->nSize = pInfo->iOverflow + 4;
+  }
+}
+#define parseCell(pPage, iCell, pInfo) \
+  btreeParseCellPtr((pPage), findCell((pPage), (iCell)), (pInfo))
+static void btreeParseCell(
+  MemPage *pPage,         /* Page containing the cell */
+  int iCell,              /* The cell index.  First cell is 0 */
+  CellInfo *pInfo         /* Fill in this structure */
+){
+  parseCell(pPage, iCell, pInfo);
 }
 
 /*
-** Move the cursor to the root page
+** Compute the total number of bytes that a Cell needs in the cell
+** data area of the btree-page.  The return number includes the cell
+** data header and the local payload, but not any overflow page or
+** the space used by the cell pointer.
 */
-static int moveToRoot(BtCursor *pCur){
-  MemPage *pRoot;
-  int rc = SQLITE_OK;
-  Btree *p = pCur->pBtree;
-  BtShared *pBt = p->pBt;
+static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
+  u8 *pIter = &pCell[pPage->childPtrSize];
+  u32 nSize;
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
-  assert( CURSOR_VALID   < CURSOR_REQUIRESEEK );
-  assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );
-  if( pCur->eState>=CURSOR_REQUIRESEEK ){
-    if( pCur->eState==CURSOR_FAULT ){
-      return pCur->skip;
+#ifdef SQLITE_DEBUG
+  /* The value returned by this function should always be the same as
+  ** the (CellInfo.nSize) value found by doing a full parse of the
+  ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of
+  ** this function verifies that this invariant is not violated. */
+  CellInfo debuginfo;
+  btreeParseCellPtr(pPage, pCell, &debuginfo);
+#endif
+
+  if( pPage->intKey ){
+    u8 *pEnd;
+    if( pPage->hasData ){
+      pIter += getVarint32(pIter, nSize);
+    }else{
+      nSize = 0;
     }
-    clearCursorPosition(pCur);
-  }
-  pRoot = pCur->pPage;
-  if( pRoot && pRoot->pgno==pCur->pgnoRoot ){
-    assert( pRoot->isInit );
+
+    /* pIter now points at the 64-bit integer key value, a variable length 
+    ** integer. The following block moves pIter to point at the first byte
+    ** past the end of the key value. */
+    pEnd = &pIter[9];
+    while( (*pIter++)&0x80 && pIter<pEnd );
   }else{
-    if( 
-      SQLITE_OK!=(rc = getAndInitPage(pBt, pCur->pgnoRoot, &pRoot, 0))
-    ){
-      pCur->eState = CURSOR_INVALID;
-      return rc;
+    pIter += getVarint32(pIter, nSize);
+  }
+
+  testcase( nSize==pPage->maxLocal );
+  testcase( nSize==pPage->maxLocal+1 );
+  if( nSize>pPage->maxLocal ){
+    int minLocal = pPage->minLocal;
+    nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4);
+    testcase( nSize==pPage->maxLocal );
+    testcase( nSize==pPage->maxLocal+1 );
+    if( nSize>pPage->maxLocal ){
+      nSize = minLocal;
     }
-    releasePage(pCur->pPage);
-    pCur->pPage = pRoot;
+    nSize += 4;
   }
-  pCur->idx = 0;
-  pCur->info.nSize = 0;
-  pCur->atLast = 0;
-  pCur->validNKey = 0;
-  if( pRoot->nCell==0 && !pRoot->leaf ){
-    Pgno subpage;
-    assert( pRoot->pgno==1 );
-    subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
-    assert( subpage>0 );
-    pCur->eState = CURSOR_VALID;
-    rc = moveToChild(pCur, subpage);
+  nSize += (u32)(pIter - pCell);
+
+  /* The minimum size of any cell is 4 bytes. */
+  if( nSize<4 ){
+    nSize = 4;
   }
-  pCur->eState = ((pCur->pPage->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
-  return rc;
+
+  assert( nSize==debuginfo.nSize );
+  return (u16)nSize;
 }
+#ifndef NDEBUG
+static u16 cellSize(MemPage *pPage, int iCell){
+  return cellSizePtr(pPage, findCell(pPage, iCell));
+}
+#endif
 
+#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Move the cursor down to the left-most leaf entry beneath the
-** entry to which it is currently pointing.
-**
-** The left-most leaf is the one with the smallest key - the first
-** in ascending order.
+** If the cell pCell, part of page pPage contains a pointer
+** to an overflow page, insert an entry into the pointer-map
+** for the overflow page.
 */
-static int moveToLeftmost(BtCursor *pCur){
-  Pgno pgno;
-  int rc = SQLITE_OK;
-  MemPage *pPage;
-
-  assert( cursorHoldsMutex(pCur) );
-  assert( pCur->eState==CURSOR_VALID );
-  while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
-    assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
-    pgno = get4byte(findCell(pPage, pCur->idx));
-    rc = moveToChild(pCur, pgno);
+static void ptrmapPutOvflPtr(MemPage *pPage, u8 *pCell, int *pRC){
+  CellInfo info;
+  if( *pRC ) return;
+  assert( pCell!=0 );
+  btreeParseCellPtr(pPage, pCell, &info);
+  assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
+  if( info.iOverflow ){
+    Pgno ovfl = get4byte(&pCell[info.iOverflow]);
+    ptrmapPut(pPage->pBt, ovfl, PTRMAP_OVERFLOW1, pPage->pgno, pRC);
   }
-  return rc;
 }
+#endif
+
 
 /*
-** Move the cursor down to the right-most leaf entry beneath the
-** page to which it is currently pointing.  Notice the difference
-** between moveToLeftmost() and moveToRightmost().  moveToLeftmost()
-** finds the left-most entry beneath the *entry* whereas moveToRightmost()
-** finds the right-most entry beneath the *page*.
-**
-** The right-most entry is the one with the largest key - the last
-** key in ascending order.
+** Defragment the page given.  All Cells are moved to the
+** end of the page and all free space is collected into one
+** big FreeBlk that occurs in between the header and cell
+** pointer array and the cell content area.
 */
-static int moveToRightmost(BtCursor *pCur){
-  Pgno pgno;
-  int rc = SQLITE_OK;
-  MemPage *pPage;
+static int defragmentPage(MemPage *pPage){
+  int i;                     /* Loop counter */
+  int pc;                    /* Address of a i-th cell */
+  int hdr;                   /* Offset to the page header */
+  int size;                  /* Size of a cell */
+  int usableSize;            /* Number of usable bytes on a page */
+  int cellOffset;            /* Offset to the cell pointer array */
+  int cbrk;                  /* Offset to the cell content area */
+  int nCell;                 /* Number of cells on the page */
+  unsigned char *data;       /* The page data */
+  unsigned char *temp;       /* Temp area for cell content */
+  int iCellFirst;            /* First allowable cell index */
+  int iCellLast;             /* Last possible cell index */
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( pCur->eState==CURSOR_VALID );
-  while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
-    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
-    pCur->idx = pPage->nCell;
-    rc = moveToChild(pCur, pgno);
+
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  assert( pPage->pBt!=0 );
+  assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
+  assert( pPage->nOverflow==0 );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  temp = sqlite3PagerTempSpace(pPage->pBt->pPager);
+  data = pPage->aData;
+  hdr = pPage->hdrOffset;
+  cellOffset = pPage->cellOffset;
+  nCell = pPage->nCell;
+  assert( nCell==get2byte(&data[hdr+3]) );
+  usableSize = pPage->pBt->usableSize;
+  cbrk = get2byte(&data[hdr+5]);
+  memcpy(&temp[cbrk], &data[cbrk], usableSize - cbrk);
+  cbrk = usableSize;
+  iCellFirst = cellOffset + 2*nCell;
+  iCellLast = usableSize - 4;
+  for(i=0; i<nCell; i++){
+    u8 *pAddr;     /* The i-th cell pointer */
+    pAddr = &data[cellOffset + i*2];
+    pc = get2byte(pAddr);
+    testcase( pc==iCellFirst );
+    testcase( pc==iCellLast );
+#if !defined(SQLITE_ENABLE_OVERSIZE_CELL_CHECK)
+    /* These conditions have already been verified in btreeInitPage()
+    ** if SQLITE_ENABLE_OVERSIZE_CELL_CHECK is defined 
+    */
+    if( pc<iCellFirst || pc>iCellLast ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+#endif
+    assert( pc>=iCellFirst && pc<=iCellLast );
+    size = cellSizePtr(pPage, &temp[pc]);
+    cbrk -= size;
+#if defined(SQLITE_ENABLE_OVERSIZE_CELL_CHECK)
+    if( cbrk<iCellFirst ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+#else
+    if( cbrk<iCellFirst || pc+size>usableSize ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+#endif
+    assert( cbrk+size<=usableSize && cbrk>=iCellFirst );
+    testcase( cbrk+size==usableSize );
+    testcase( pc+size==usableSize );
+    memcpy(&data[cbrk], &temp[pc], size);
+    put2byte(pAddr, cbrk);
   }
-  if( rc==SQLITE_OK ){
-    pCur->idx = pPage->nCell - 1;
-    pCur->info.nSize = 0;
-    pCur->validNKey = 0;
+  assert( cbrk>=iCellFirst );
+  put2byte(&data[hdr+5], cbrk);
+  data[hdr+1] = 0;
+  data[hdr+2] = 0;
+  data[hdr+7] = 0;
+  memset(&data[iCellFirst], 0, cbrk-iCellFirst);
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  if( cbrk-iCellFirst!=pPage->nFree ){
+    return SQLITE_CORRUPT_BKPT;
   }
   return SQLITE_OK;
 }
 
-/* Move the cursor to the first entry in the table.  Return SQLITE_OK
-** on success.  Set *pRes to 0 if the cursor actually points to something
-** or set *pRes to 1 if the table is empty.
+/*
+** Allocate nByte bytes of space from within the B-Tree page passed
+** as the first argument. Write into *pIdx the index into pPage->aData[]
+** of the first byte of allocated space. Return either SQLITE_OK or
+** an error code (usually SQLITE_CORRUPT).
+**
+** The caller guarantees that there is sufficient space to make the
+** allocation.  This routine might need to defragment in order to bring
+** all the space together, however.  This routine will avoid using
+** the first two bytes past the cell pointer area since presumably this
+** allocation is being made in order to insert a new cell, so we will
+** also end up needing a new cell pointer.
 */
-SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
-  int rc;
+static int allocateSpace(MemPage *pPage, int nByte, int *pIdx){
+  const int hdr = pPage->hdrOffset;    /* Local cache of pPage->hdrOffset */
+  u8 * const data = pPage->aData;      /* Local cache of pPage->aData */
+  int nFrag;                           /* Number of fragmented bytes on pPage */
+  int top;                             /* First byte of cell content area */
+  int gap;        /* First byte of gap between cell pointers and cell content */
+  int rc;         /* Integer return code */
+  
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  assert( pPage->pBt );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( nByte>=0 );  /* Minimum cell size is 4 */
+  assert( pPage->nFree>=nByte );
+  assert( pPage->nOverflow==0 );
+  assert( nByte<pPage->pBt->usableSize-8 );
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
-  rc = moveToRoot(pCur);
-  if( rc==SQLITE_OK ){
-    if( pCur->eState==CURSOR_INVALID ){
-      assert( pCur->pPage->nCell==0 );
-      *pRes = 1;
-      rc = SQLITE_OK;
-    }else{
-      assert( pCur->pPage->nCell>0 );
-      *pRes = 0;
-      rc = moveToLeftmost(pCur);
+  nFrag = data[hdr+7];
+  assert( pPage->cellOffset == hdr + 12 - 4*pPage->leaf );
+  gap = pPage->cellOffset + 2*pPage->nCell;
+  top = get2byte(&data[hdr+5]);
+  if( gap>top ) return SQLITE_CORRUPT_BKPT;
+  testcase( gap+2==top );
+  testcase( gap+1==top );
+  testcase( gap==top );
+
+  if( nFrag>=60 ){
+    /* Always defragment highly fragmented pages */
+    rc = defragmentPage(pPage);
+    if( rc ) return rc;
+    top = get2byte(&data[hdr+5]);
+  }else if( gap+2<=top ){
+    /* Search the freelist looking for a free slot big enough to satisfy 
+    ** the request. The allocation is made from the first free slot in 
+    ** the list that is large enough to accomadate it.
+    */
+    int pc, addr;
+    for(addr=hdr+1; (pc = get2byte(&data[addr]))>0; addr=pc){
+      int size = get2byte(&data[pc+2]);     /* Size of free slot */
+      if( size>=nByte ){
+        int x = size - nByte;
+        testcase( x==4 );
+        testcase( x==3 );
+        if( x<4 ){
+          /* Remove the slot from the free-list. Update the number of
+          ** fragmented bytes within the page. */
+          memcpy(&data[addr], &data[pc], 2);
+          data[hdr+7] = (u8)(nFrag + x);
+        }else{
+          /* The slot remains on the free-list. Reduce its size to account
+          ** for the portion used by the new allocation. */
+          put2byte(&data[pc+2], x);
+        }
+        *pIdx = pc + x;
+        return SQLITE_OK;
+      }
     }
   }
-  return rc;
+
+  /* Check to make sure there is enough space in the gap to satisfy
+  ** the allocation.  If not, defragment.
+  */
+  testcase( gap+2+nByte==top );
+  if( gap+2+nByte>top ){
+    rc = defragmentPage(pPage);
+    if( rc ) return rc;
+    top = get2byte(&data[hdr+5]);
+    assert( gap+nByte<=top );
+  }
+
+
+  /* Allocate memory from the gap in between the cell pointer array
+  ** and the cell content area.  The btreeInitPage() call has already
+  ** validated the freelist.  Given that the freelist is valid, there
+  ** is no way that the allocation can extend off the end of the page.
+  ** The assert() below verifies the previous sentence.
+  */
+  top -= nByte;
+  put2byte(&data[hdr+5], top);
+  assert( top+nByte <= pPage->pBt->usableSize );
+  *pIdx = top;
+  return SQLITE_OK;
 }
 
-/* Move the cursor to the last entry in the table.  Return SQLITE_OK
-** on success.  Set *pRes to 0 if the cursor actually points to something
-** or set *pRes to 1 if the table is empty.
+/*
+** Return a section of the pPage->aData to the freelist.
+** The first byte of the new free block is pPage->aDisk[start]
+** and the size of the block is "size" bytes.
+**
+** Most of the effort here is involved in coalesing adjacent
+** free blocks into a single big free block.
 */
-SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
-  int rc;
- 
-  assert( cursorHoldsMutex(pCur) );
-  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
-  rc = moveToRoot(pCur);
-  if( rc==SQLITE_OK ){
-    if( CURSOR_INVALID==pCur->eState ){
-      assert( pCur->pPage->nCell==0 );
-      *pRes = 1;
+static int freeSpace(MemPage *pPage, int start, int size){
+  int addr, pbegin, hdr;
+  int iLast;                        /* Largest possible freeblock offset */
+  unsigned char *data = pPage->aData;
+
+  assert( pPage->pBt!=0 );
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  assert( start>=pPage->hdrOffset+6+pPage->childPtrSize );
+  assert( (start + size)<=pPage->pBt->usableSize );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( size>=0 );   /* Minimum cell size is 4 */
+
+#ifdef SQLITE_SECURE_DELETE
+  /* Overwrite deleted information with zeros when the SECURE_DELETE 
+  ** option is enabled at compile-time */
+  memset(&data[start], 0, size);
+#endif
+
+  /* Add the space back into the linked list of freeblocks.  Note that
+  ** even though the freeblock list was checked by btreeInitPage(),
+  ** btreeInitPage() did not detect overlapping cells or
+  ** freeblocks that overlapped cells.   Nor does it detect when the
+  ** cell content area exceeds the value in the page header.  If these
+  ** situations arise, then subsequent insert operations might corrupt
+  ** the freelist.  So we do need to check for corruption while scanning
+  ** the freelist.
+  */
+  hdr = pPage->hdrOffset;
+  addr = hdr + 1;
+  iLast = pPage->pBt->usableSize - 4;
+  assert( start<=iLast );
+  while( (pbegin = get2byte(&data[addr]))<start && pbegin>0 ){
+    if( pbegin<addr+4 ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+    addr = pbegin;
+  }
+  if( pbegin>iLast ){
+    return SQLITE_CORRUPT_BKPT;
+  }
+  assert( pbegin>addr || pbegin==0 );
+  put2byte(&data[addr], start);
+  put2byte(&data[start], pbegin);
+  put2byte(&data[start+2], size);
+  pPage->nFree = pPage->nFree + (u16)size;
+
+  /* Coalesce adjacent free blocks */
+  addr = hdr + 1;
+  while( (pbegin = get2byte(&data[addr]))>0 ){
+    int pnext, psize, x;
+    assert( pbegin>addr );
+    assert( pbegin<=pPage->pBt->usableSize-4 );
+    pnext = get2byte(&data[pbegin]);
+    psize = get2byte(&data[pbegin+2]);
+    if( pbegin + psize + 3 >= pnext && pnext>0 ){
+      int frag = pnext - (pbegin+psize);
+      if( (frag<0) || (frag>(int)data[hdr+7]) ){
+        return SQLITE_CORRUPT_BKPT;
+      }
+      data[hdr+7] -= (u8)frag;
+      x = get2byte(&data[pnext]);
+      put2byte(&data[pbegin], x);
+      x = pnext + get2byte(&data[pnext+2]) - pbegin;
+      put2byte(&data[pbegin+2], x);
     }else{
-      assert( pCur->eState==CURSOR_VALID );
-      *pRes = 0;
-      rc = moveToRightmost(pCur);
-      getCellInfo(pCur);
-      pCur->atLast = rc==SQLITE_OK;
+      addr = pbegin;
     }
   }
-  return rc;
+
+  /* If the cell content area begins with a freeblock, remove it. */
+  if( data[hdr+1]==data[hdr+5] && data[hdr+2]==data[hdr+6] ){
+    int top;
+    pbegin = get2byte(&data[hdr+1]);
+    memcpy(&data[hdr+1], &data[pbegin], 2);
+    top = get2byte(&data[hdr+5]) + get2byte(&data[pbegin+2]);
+    put2byte(&data[hdr+5], top);
+  }
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  return SQLITE_OK;
 }
 
-/* Move the cursor so that it points to an entry near the key 
-** specified by pKey/nKey/pUnKey. Return a success code.
-**
-** For INTKEY tables, only the nKey parameter is used.  pKey 
-** and pUnKey must be NULL.  For index tables, either pUnKey
-** must point to a key that has already been unpacked, or else
-** pKey/nKey describes a blob containing the key.
-**
-** If an exact match is not found, then the cursor is always
-** left pointing at a leaf page which would hold the entry if it
-** were present.  The cursor might point to an entry that comes
-** before or after the key.
-**
-** The result of comparing the key with the entry to which the
-** cursor is written to *pRes if pRes!=NULL.  The meaning of
-** this value is as follows:
-**
-**     *pRes<0      The cursor is left pointing at an entry that
-**                  is smaller than pKey or if the table is empty
-**                  and the cursor is therefore left point to nothing.
+/*
+** Decode the flags byte (the first byte of the header) for a page
+** and initialize fields of the MemPage structure accordingly.
 **
-**     *pRes==0     The cursor is left pointing at an entry that
-**                  exactly matches pKey.
+** Only the following combinations are supported.  Anything different
+** indicates a corrupt database files:
 **
-**     *pRes>0      The cursor is left pointing at an entry that
-**                  is larger than pKey.
+**         PTF_ZERODATA
+**         PTF_ZERODATA | PTF_LEAF
+**         PTF_LEAFDATA | PTF_INTKEY
+**         PTF_LEAFDATA | PTF_INTKEY | PTF_LEAF
+*/
+static int decodeFlags(MemPage *pPage, int flagByte){
+  BtShared *pBt;     /* A copy of pPage->pBt */
+
+  assert( pPage->hdrOffset==(pPage->pgno==1 ? 100 : 0) );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  pPage->leaf = (u8)(flagByte>>3);  assert( PTF_LEAF == 1<<3 );
+  flagByte &= ~PTF_LEAF;
+  pPage->childPtrSize = 4-4*pPage->leaf;
+  pBt = pPage->pBt;
+  if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){
+    pPage->intKey = 1;
+    pPage->hasData = pPage->leaf;
+    pPage->maxLocal = pBt->maxLeaf;
+    pPage->minLocal = pBt->minLeaf;
+  }else if( flagByte==PTF_ZERODATA ){
+    pPage->intKey = 0;
+    pPage->hasData = 0;
+    pPage->maxLocal = pBt->maxLocal;
+    pPage->minLocal = pBt->minLocal;
+  }else{
+    return SQLITE_CORRUPT_BKPT;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Initialize the auxiliary information for a disk block.
 **
+** Return SQLITE_OK on success.  If we see that the page does
+** not contain a well-formed database page, then return 
+** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
+** guarantee that the page is well-formed.  It only shows that
+** we failed to detect any corruption.
 */
-SQLITE_PRIVATE int sqlite3BtreeMoveto(
-  BtCursor *pCur,        /* The cursor to be moved */
-  const void *pKey,      /* The key content for indices.  Not used by tables */
-  UnpackedRecord *pUnKey,/* Unpacked version of pKey */
-  i64 nKey,              /* Size of pKey.  Or the key for tables */
-  int biasRight,         /* If true, bias the search to the high end */
-  int *pRes              /* Search result flag */
-){
-  int rc;
-  char aSpace[200];
+static int btreeInitPage(MemPage *pPage){
 
-  assert( cursorHoldsMutex(pCur) );
-  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  assert( pPage->pBt!=0 );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
+  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
+  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
 
-  /* If the cursor is already positioned at the point we are trying
-  ** to move to, then just return without doing any work */
-  if( pCur->eState==CURSOR_VALID && pCur->validNKey && pCur->pPage->intKey ){
-    if( pCur->info.nKey==nKey ){
-      *pRes = 0;
-      return SQLITE_OK;
-    }
-    if( pCur->atLast && pCur->info.nKey<nKey ){
-      *pRes = -1;
-      return SQLITE_OK;
-    }
-  }
+  if( !pPage->isInit ){
+    u16 pc;            /* Address of a freeblock within pPage->aData[] */
+    u8 hdr;            /* Offset to beginning of page header */
+    u8 *data;          /* Equal to pPage->aData */
+    BtShared *pBt;        /* The main btree structure */
+    u16 usableSize;    /* Amount of usable space on each page */
+    u16 cellOffset;    /* Offset from start of page to first cell pointer */
+    u16 nFree;         /* Number of unused bytes on the page */
+    u16 top;           /* First byte of the cell content area */
+    int iCellFirst;    /* First allowable cell or freeblock offset */
+    int iCellLast;     /* Last possible cell or freeblock offset */
 
+    pBt = pPage->pBt;
 
-  rc = moveToRoot(pCur);
-  if( rc ){
-    return rc;
-  }
-  assert( pCur->pPage );
-  assert( pCur->pPage->isInit );
-  if( pCur->eState==CURSOR_INVALID ){
-    *pRes = -1;
-    assert( pCur->pPage->nCell==0 );
-    return SQLITE_OK;
-  }
-  if( pCur->pPage->intKey ){
-    /* We are given an SQL table to search.  The key is the integer
-    ** rowid contained in nKey.  pKey and pUnKey should both be NULL */
-    assert( pUnKey==0 );
-    assert( pKey==0 );
-  }else if( pUnKey==0 ){
-    /* We are to search an SQL index using a key encoded as a blob.
-    ** The blob is found at pKey and is nKey bytes in length.  Unpack
-    ** this key so that we can use it. */
-    assert( pKey!=0 );
-    pUnKey = sqlite3VdbeRecordUnpack(pCur->pKeyInfo, nKey, pKey,
-                                   aSpace, sizeof(aSpace));
-    if( pUnKey==0 ) return SQLITE_NOMEM;
-  }else{
-    /* We are to search an SQL index using a key that is already unpacked
-    ** and handed to us in pUnKey. */
-    assert( pKey==0 );
-  }
-  for(;;){
-    int lwr, upr;
-    Pgno chldPg;
-    MemPage *pPage = pCur->pPage;
-    int c = -1;  /* pRes return if table is empty must be -1 */
-    lwr = 0;
-    upr = pPage->nCell-1;
-    if( !pPage->intKey && pUnKey==0 ){
-      rc = SQLITE_CORRUPT_BKPT;
-      goto moveto_finish;
-    }
-    if( biasRight ){
-      pCur->idx = upr;
-    }else{
-      pCur->idx = (upr+lwr)/2;
+    hdr = pPage->hdrOffset;
+    data = pPage->aData;
+    if( decodeFlags(pPage, data[hdr]) ) return SQLITE_CORRUPT_BKPT;
+    assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
+    pPage->maskPage = pBt->pageSize - 1;
+    pPage->nOverflow = 0;
+    usableSize = pBt->usableSize;
+    pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
+    top = get2byte(&data[hdr+5]);
+    pPage->nCell = get2byte(&data[hdr+3]);
+    if( pPage->nCell>MX_CELL(pBt) ){
+      /* To many cells for a single page.  The page must be corrupt */
+      return SQLITE_CORRUPT_BKPT;
     }
-    if( lwr<=upr ) for(;;){
-      void *pCellKey;
-      i64 nCellKey;
-      pCur->info.nSize = 0;
-      pCur->validNKey = 1;
-      if( pPage->intKey ){
-        u8 *pCell;
-        pCell = findCell(pPage, pCur->idx) + pPage->childPtrSize;
-        if( pPage->hasData ){
-          u32 dummy;
-          pCell += getVarint32(pCell, dummy);
-        }
-        getVarint(pCell, (u64*)&nCellKey);
-        if( nCellKey==nKey ){
-          c = 0;
-        }else if( nCellKey<nKey ){
-          c = -1;
-        }else{
-          assert( nCellKey>nKey );
-          c = +1;
-        }
-      }else{
-        int available;
-        pCellKey = (void *)fetchPayload(pCur, &available, 0);
-        nCellKey = pCur->info.nKey;
-        if( available>=nCellKey ){
-          c = sqlite3VdbeRecordCompare(nCellKey, pCellKey, pUnKey);
-        }else{
-          pCellKey = sqlite3_malloc( nCellKey );
-          if( pCellKey==0 ){
-            rc = SQLITE_NOMEM;
-            goto moveto_finish;
-          }
-          rc = sqlite3BtreeKey(pCur, 0, nCellKey, (void *)pCellKey);
-          c = sqlite3VdbeRecordCompare(nCellKey, pCellKey, pUnKey);
-          sqlite3_free(pCellKey);
-          if( rc ) goto moveto_finish;
+    testcase( pPage->nCell==MX_CELL(pBt) );
+
+    /* A malformed database page might cause us to read past the end
+    ** of page when parsing a cell.  
+    **
+    ** The following block of code checks early to see if a cell extends
+    ** past the end of a page boundary and causes SQLITE_CORRUPT to be 
+    ** returned if it does.
+    */
+    iCellFirst = cellOffset + 2*pPage->nCell;
+    iCellLast = usableSize - 4;
+#if defined(SQLITE_ENABLE_OVERSIZE_CELL_CHECK)
+    {
+      int i;            /* Index into the cell pointer array */
+      int sz;           /* Size of a cell */
+
+      if( !pPage->leaf ) iCellLast--;
+      for(i=0; i<pPage->nCell; i++){
+        pc = get2byte(&data[cellOffset+i*2]);
+        testcase( pc==iCellFirst );
+        testcase( pc==iCellLast );
+        if( pc<iCellFirst || pc>iCellLast ){
+          return SQLITE_CORRUPT_BKPT;
         }
-      }
-      if( c==0 ){
-        pCur->info.nKey = nCellKey;
-        if( pPage->leafData && !pPage->leaf ){
-          lwr = pCur->idx;
-          upr = lwr - 1;
-          break;
-        }else{
-          if( pRes ) *pRes = 0;
-          rc = SQLITE_OK;
-          goto moveto_finish;
+        sz = cellSizePtr(pPage, &data[pc]);
+        testcase( pc+sz==usableSize );
+        if( pc+sz>usableSize ){
+          return SQLITE_CORRUPT_BKPT;
         }
       }
-      if( c<0 ){
-        lwr = pCur->idx+1;
-      }else{
-        upr = pCur->idx-1;
+      if( !pPage->leaf ) iCellLast++;
+    }  
+#endif
+
+    /* Compute the total free space on the page */
+    pc = get2byte(&data[hdr+1]);
+    nFree = data[hdr+7] + top;
+    while( pc>0 ){
+      u16 next, size;
+      if( pc<iCellFirst || pc>iCellLast ){
+        /* Start of free block is off the page */
+        return SQLITE_CORRUPT_BKPT; 
       }
-      if( lwr>upr ){
-        pCur->info.nKey = nCellKey;
-        break;
+      next = get2byte(&data[pc]);
+      size = get2byte(&data[pc+2]);
+      if( (next>0 && next<=pc+size+3) || pc+size>usableSize ){
+        /* Free blocks must be in ascending order. And the last byte of
+	** the free-block must lie on the database page.  */
+        return SQLITE_CORRUPT_BKPT; 
       }
-      pCur->idx = (lwr+upr)/2;
-    }
-    assert( lwr==upr+1 );
-    assert( pPage->isInit );
-    if( pPage->leaf ){
-      chldPg = 0;
-    }else if( lwr>=pPage->nCell ){
-      chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
-    }else{
-      chldPg = get4byte(findCell(pPage, lwr));
+      nFree = nFree + size;
+      pc = next;
     }
-    if( chldPg==0 ){
-      assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
-      if( pRes ) *pRes = c;
-      rc = SQLITE_OK;
-      goto moveto_finish;
+
+    /* At this point, nFree contains the sum of the offset to the start
+    ** of the cell-content area plus the number of free bytes within
+    ** the cell-content area. If this is greater than the usable-size
+    ** of the page, then the page must be corrupted. This check also
+    ** serves to verify that the offset to the start of the cell-content
+    ** area, according to the page header, lies within the page.
+    */
+    if( nFree>usableSize ){
+      return SQLITE_CORRUPT_BKPT; 
     }
-    pCur->idx = lwr;
-    pCur->info.nSize = 0;
-    pCur->validNKey = 0;
-    rc = moveToChild(pCur, chldPg);
-    if( rc ) goto moveto_finish;
-  }
-moveto_finish:
-  if( pKey ){
-    /* If we created our own unpacked key at the top of this
-    ** procedure, then destroy that key before returning. */
-    sqlite3VdbeDeleteUnpackedRecord(pUnKey);
+    pPage->nFree = (u16)(nFree - iCellFirst);
+    pPage->isInit = 1;
   }
-  return rc;
+  return SQLITE_OK;
 }
 
-
 /*
-** Return TRUE if the cursor is not pointing at an entry of the table.
-**
-** TRUE will be returned after a call to sqlite3BtreeNext() moves
-** past the last entry in the table or sqlite3BtreePrev() moves past
-** the first entry.  TRUE is also returned if the table is empty.
+** Set up a raw page so that it looks like a database page holding
+** no entries.
 */
-SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor *pCur){
-  /* TODO: What if the cursor is in CURSOR_REQUIRESEEK but all table entries
-  ** have been deleted? This API will need to change to return an error code
-  ** as well as the boolean result value.
-  */
-  return (CURSOR_VALID!=pCur->eState);
+static void zeroPage(MemPage *pPage, int flags){
+  unsigned char *data = pPage->aData;
+  BtShared *pBt = pPage->pBt;
+  u8 hdr = pPage->hdrOffset;
+  u16 first;
+
+  assert( sqlite3PagerPagenumber(pPage->pDbPage)==pPage->pgno );
+  assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
+  assert( sqlite3PagerGetData(pPage->pDbPage) == data );
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  /*memset(&data[hdr], 0, pBt->usableSize - hdr);*/
+  data[hdr] = (char)flags;
+  first = hdr + 8 + 4*((flags&PTF_LEAF)==0 ?1:0);
+  memset(&data[hdr+1], 0, 4);
+  data[hdr+7] = 0;
+  put2byte(&data[hdr+5], pBt->usableSize);
+  pPage->nFree = pBt->usableSize - first;
+  decodeFlags(pPage, flags);
+  pPage->hdrOffset = hdr;
+  pPage->cellOffset = first;
+  pPage->nOverflow = 0;
+  assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
+  pPage->maskPage = pBt->pageSize - 1;
+  pPage->nCell = 0;
+  pPage->isInit = 1;
 }
 
+
 /*
-** Return the database connection handle for a cursor.
+** Convert a DbPage obtained from the pager into a MemPage used by
+** the btree layer.
 */
-SQLITE_PRIVATE sqlite3 *sqlite3BtreeCursorDb(const BtCursor *pCur){
-  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
-  return pCur->pBtree->db;
+static MemPage *btreePageFromDbPage(DbPage *pDbPage, Pgno pgno, BtShared *pBt){
+  MemPage *pPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
+  pPage->aData = sqlite3PagerGetData(pDbPage);
+  pPage->pDbPage = pDbPage;
+  pPage->pBt = pBt;
+  pPage->pgno = pgno;
+  pPage->hdrOffset = pPage->pgno==1 ? 100 : 0;
+  return pPage; 
 }
 
 /*
-** Advance the cursor to the next entry in the database.  If
-** successful then set *pRes=0.  If the cursor
-** was already pointing to the last entry in the database before
-** this routine was called, then set *pRes=1.
+** Get a page from the pager.  Initialize the MemPage.pBt and
+** MemPage.aData elements if needed.
+**
+** If the noContent flag is set, it means that we do not care about
+** the content of the page at this time.  So do not go to the disk
+** to fetch the content.  Just fill in the content with zeros for now.
+** If in the future we call sqlite3PagerWrite() on this page, that
+** means we have started to be concerned about content and the disk
+** read should occur at that point.
 */
-SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
+static int btreeGetPage(
+  BtShared *pBt,       /* The btree */
+  Pgno pgno,           /* Number of the page to fetch */
+  MemPage **ppPage,    /* Return the page in this parameter */
+  int noContent        /* Do not load page content if true */
+){
   int rc;
-  MemPage *pPage;
+  DbPage *pDbPage;
 
-  assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  assert( pRes!=0 );
-  pPage = pCur->pPage;
-  if( CURSOR_INVALID==pCur->eState ){
-    *pRes = 1;
-    return SQLITE_OK;
-  }
-  if( pCur->skip>0 ){
-    pCur->skip = 0;
-    *pRes = 0;
-    return SQLITE_OK;
-  }
-  pCur->skip = 0;
-
-  assert( pPage->isInit );
-  assert( pCur->idx<pPage->nCell );
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, noContent);
+  if( rc ) return rc;
+  *ppPage = btreePageFromDbPage(pDbPage, pgno, pBt);
+  return SQLITE_OK;
+}
 
-  pCur->idx++;
-  pCur->info.nSize = 0;
-  pCur->validNKey = 0;
-  if( pCur->idx>=pPage->nCell ){
-    if( !pPage->leaf ){
-      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
-      if( rc ) return rc;
-      rc = moveToLeftmost(pCur);
-      *pRes = 0;
-      return rc;
-    }
-    do{
-      if( sqlite3BtreeIsRootPage(pPage) ){
-        *pRes = 1;
-        pCur->eState = CURSOR_INVALID;
-        return SQLITE_OK;
-      }
-      sqlite3BtreeMoveToParent(pCur);
-      pPage = pCur->pPage;
-    }while( pCur->idx>=pPage->nCell );
-    *pRes = 0;
-    if( pPage->leafData ){
-      rc = sqlite3BtreeNext(pCur, pRes);
-    }else{
-      rc = SQLITE_OK;
-    }
-    return rc;
-  }
-  *pRes = 0;
-  if( pPage->leaf ){
-    return SQLITE_OK;
+/*
+** Retrieve a page from the pager cache. If the requested page is not
+** already in the pager cache return NULL. Initialize the MemPage.pBt and
+** MemPage.aData elements if needed.
+*/
+static MemPage *btreePageLookup(BtShared *pBt, Pgno pgno){
+  DbPage *pDbPage;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  pDbPage = sqlite3PagerLookup(pBt->pPager, pgno);
+  if( pDbPage ){
+    return btreePageFromDbPage(pDbPage, pgno, pBt);
   }
-  rc = moveToLeftmost(pCur);
-  return rc;
+  return 0;
 }
 
-
 /*
-** Step the cursor to the back to the previous entry in the database.  If
-** successful then set *pRes=0.  If the cursor
-** was already pointing to the first entry in the database before
-** this routine was called, then set *pRes=1.
+** Return the size of the database file in pages. If there is any kind of
+** error, return ((unsigned int)-1).
 */
-SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
+static Pgno pagerPagecount(BtShared *pBt){
+  int nPage = -1;
   int rc;
-  Pgno pgno;
-  MemPage *pPage;
-
-  assert( cursorHoldsMutex(pCur) );
-  rc = restoreOrClearCursorPosition(pCur);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  pCur->atLast = 0;
-  if( CURSOR_INVALID==pCur->eState ){
-    *pRes = 1;
-    return SQLITE_OK;
-  }
-  if( pCur->skip<0 ){
-    pCur->skip = 0;
-    *pRes = 0;
-    return SQLITE_OK;
-  }
-  pCur->skip = 0;
-
-  pPage = pCur->pPage;
-  assert( pPage->isInit );
-  assert( pCur->idx>=0 );
-  if( !pPage->leaf ){
-    pgno = get4byte( findCell(pPage, pCur->idx) );
-    rc = moveToChild(pCur, pgno);
-    if( rc ){
-      return rc;
-    }
-    rc = moveToRightmost(pCur);
-  }else{
-    while( pCur->idx==0 ){
-      if( sqlite3BtreeIsRootPage(pPage) ){
-        pCur->eState = CURSOR_INVALID;
-        *pRes = 1;
-        return SQLITE_OK;
-      }
-      sqlite3BtreeMoveToParent(pCur);
-      pPage = pCur->pPage;
-    }
-    pCur->idx--;
-    pCur->info.nSize = 0;
-    pCur->validNKey = 0;
-    if( pPage->leafData && !pPage->leaf ){
-      rc = sqlite3BtreePrevious(pCur, pRes);
-    }else{
-      rc = SQLITE_OK;
-    }
-  }
-  *pRes = 0;
-  return rc;
+  assert( pBt->pPage1 );
+  rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
+  assert( rc==SQLITE_OK || nPage==-1 );
+  return (Pgno)nPage;
 }
 
 /*
-** Allocate a new page from the database file.
-**
-** The new page is marked as dirty.  (In other words, sqlite3PagerWrite()
-** has already been called on the new page.)  The new page has also
-** been referenced and the calling routine is responsible for calling
-** sqlite3PagerUnref() on the new page when it is done.
-**
-** SQLITE_OK is returned on success.  Any other return value indicates
-** an error.  *ppPage and *pPgno are undefined in the event of an error.
-** Do not invoke sqlite3PagerUnref() on *ppPage if an error is returned.
-**
-** If the "nearby" parameter is not 0, then a (feeble) effort is made to 
-** locate a page close to the page number "nearby".  This can be used in an
-** attempt to keep related pages close to each other in the database file,
-** which in turn can make database access faster.
+** Get a page from the pager and initialize it.  This routine is just a
+** convenience wrapper around separate calls to btreeGetPage() and 
+** btreeInitPage().
 **
-** If the "exact" parameter is not 0, and the page-number nearby exists 
-** anywhere on the free-list, then it is guarenteed to be returned. This
-** is only used by auto-vacuum databases when allocating a new table.
+** If an error occurs, then the value *ppPage is set to is undefined. It
+** may remain unchanged, or it may be set to an invalid value.
 */
-static int allocateBtreePage(
-  BtShared *pBt, 
-  MemPage **ppPage, 
-  Pgno *pPgno, 
-  Pgno nearby,
-  u8 exact
+static int getAndInitPage(
+  BtShared *pBt,          /* The database file */
+  Pgno pgno,           /* Number of the page to get */
+  MemPage **ppPage     /* Write the page pointer here */
 ){
-  MemPage *pPage1;
   int rc;
-  int n;     /* Number of pages on the freelist */
-  int k;     /* Number of leaves on the trunk of the freelist */
-  MemPage *pTrunk = 0;
-  MemPage *pPrevTrunk = 0;
-
+  TESTONLY( Pgno iLastPg = pagerPagecount(pBt); )
   assert( sqlite3_mutex_held(pBt->mutex) );
-  pPage1 = pBt->pPage1;
-  n = get4byte(&pPage1->aData[36]);
-  if( n>0 ){
-    /* There are pages on the freelist.  Reuse one of those pages. */
-    Pgno iTrunk;
-    u8 searchList = 0; /* If the free-list must be searched for 'nearby' */
-    
-    /* If the 'exact' parameter was true and a query of the pointer-map
-    ** shows that the page 'nearby' is somewhere on the free-list, then
-    ** the entire-list will be searched for that page.
-    */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( exact && nearby<=sqlite3PagerPagecount(pBt->pPager) ){
-      u8 eType;
-      assert( nearby>0 );
-      assert( pBt->autoVacuum );
-      rc = ptrmapGet(pBt, nearby, &eType, 0);
-      if( rc ) return rc;
-      if( eType==PTRMAP_FREEPAGE ){
-        searchList = 1;
-      }
-      *pPgno = nearby;
-    }
-#endif
-
-    /* Decrement the free-list count by 1. Set iTrunk to the index of the
-    ** first free-list trunk page. iPrevTrunk is initially 1.
-    */
-    rc = sqlite3PagerWrite(pPage1->pDbPage);
-    if( rc ) return rc;
-    put4byte(&pPage1->aData[36], n-1);
-
-    /* The code within this loop is run only once if the 'searchList' variable
-    ** is not true. Otherwise, it runs once for each trunk-page on the
-    ** free-list until the page 'nearby' is located.
-    */
-    do {
-      pPrevTrunk = pTrunk;
-      if( pPrevTrunk ){
-        iTrunk = get4byte(&pPrevTrunk->aData[0]);
-      }else{
-        iTrunk = get4byte(&pPage1->aData[32]);
-      }
-      rc = sqlite3BtreeGetPage(pBt, iTrunk, &pTrunk, 0);
-      if( rc ){
-        pTrunk = 0;
-        goto end_allocate_page;
-      }
-
-      k = get4byte(&pTrunk->aData[4]);
-      if( k==0 && !searchList ){
-        /* The trunk has no leaves and the list is not being searched. 
-        ** So extract the trunk page itself and use it as the newly 
-        ** allocated page */
-        assert( pPrevTrunk==0 );
-        rc = sqlite3PagerWrite(pTrunk->pDbPage);
-        if( rc ){
-          goto end_allocate_page;
-        }
-        *pPgno = iTrunk;
-        memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
-        *ppPage = pTrunk;
-        pTrunk = 0;
-        TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
-      }else if( k>pBt->usableSize/4 - 8 ){
-        /* Value of k is out of range.  Database corruption */
-        rc = SQLITE_CORRUPT_BKPT;
-        goto end_allocate_page;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      }else if( searchList && nearby==iTrunk ){
-        /* The list is being searched and this trunk page is the page
-        ** to allocate, regardless of whether it has leaves.
-        */
-        assert( *pPgno==iTrunk );
-        *ppPage = pTrunk;
-        searchList = 0;
-        rc = sqlite3PagerWrite(pTrunk->pDbPage);
-        if( rc ){
-          goto end_allocate_page;
-        }
-        if( k==0 ){
-          if( !pPrevTrunk ){
-            memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
-          }else{
-            memcpy(&pPrevTrunk->aData[0], &pTrunk->aData[0], 4);
-          }
-        }else{
-          /* The trunk page is required by the caller but it contains 
-          ** pointers to free-list leaves. The first leaf becomes a trunk
-          ** page in this case.
-          */
-          MemPage *pNewTrunk;
-          Pgno iNewTrunk = get4byte(&pTrunk->aData[8]);
-          rc = sqlite3BtreeGetPage(pBt, iNewTrunk, &pNewTrunk, 0);
-          if( rc!=SQLITE_OK ){
-            goto end_allocate_page;
-          }
-          rc = sqlite3PagerWrite(pNewTrunk->pDbPage);
-          if( rc!=SQLITE_OK ){
-            releasePage(pNewTrunk);
-            goto end_allocate_page;
-          }
-          memcpy(&pNewTrunk->aData[0], &pTrunk->aData[0], 4);
-          put4byte(&pNewTrunk->aData[4], k-1);
-          memcpy(&pNewTrunk->aData[8], &pTrunk->aData[12], (k-1)*4);
-          releasePage(pNewTrunk);
-          if( !pPrevTrunk ){
-            put4byte(&pPage1->aData[32], iNewTrunk);
-          }else{
-            rc = sqlite3PagerWrite(pPrevTrunk->pDbPage);
-            if( rc ){
-              goto end_allocate_page;
-            }
-            put4byte(&pPrevTrunk->aData[0], iNewTrunk);
-          }
-        }
-        pTrunk = 0;
-        TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
-#endif
-      }else{
-        /* Extract a leaf from the trunk */
-        int closest;
-        Pgno iPage;
-        unsigned char *aData = pTrunk->aData;
-        rc = sqlite3PagerWrite(pTrunk->pDbPage);
-        if( rc ){
-          goto end_allocate_page;
-        }
-        if( nearby>0 ){
-          int i, dist;
-          closest = 0;
-          dist = get4byte(&aData[8]) - nearby;
-          if( dist<0 ) dist = -dist;
-          for(i=1; i<k; i++){
-            int d2 = get4byte(&aData[8+i*4]) - nearby;
-            if( d2<0 ) d2 = -d2;
-            if( d2<dist ){
-              closest = i;
-              dist = d2;
-            }
-          }
-        }else{
-          closest = 0;
-        }
-
-        iPage = get4byte(&aData[8+closest*4]);
-        if( !searchList || iPage==nearby ){
-          *pPgno = iPage;
-          if( *pPgno>sqlite3PagerPagecount(pBt->pPager) ){
-            /* Free page off the end of the file */
-            rc = SQLITE_CORRUPT_BKPT;
-            goto end_allocate_page;
-          }
-          TRACE(("ALLOCATE: %d was leaf %d of %d on trunk %d"
-                 ": %d more free pages\n",
-                 *pPgno, closest+1, k, pTrunk->pgno, n-1));
-          if( closest<k-1 ){
-            memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
-          }
-          put4byte(&aData[4], k-1);
-          rc = sqlite3BtreeGetPage(pBt, *pPgno, ppPage, 1);
-          if( rc==SQLITE_OK ){
-            sqlite3PagerDontRollback((*ppPage)->pDbPage);
-            rc = sqlite3PagerWrite((*ppPage)->pDbPage);
-            if( rc!=SQLITE_OK ){
-              releasePage(*ppPage);
-            }
-          }
-          searchList = 0;
-        }
-      }
-      releasePage(pPrevTrunk);
-      pPrevTrunk = 0;
-    }while( searchList );
-  }else{
-    /* There are no pages on the freelist, so create a new page at the
-    ** end of the file */
-    *pPgno = sqlite3PagerPagecount(pBt->pPager) + 1;
-
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pBt->nTrunc ){
-      /* An incr-vacuum has already run within this transaction. So the
-      ** page to allocate is not from the physical end of the file, but
-      ** at pBt->nTrunc. 
-      */
-      *pPgno = pBt->nTrunc+1;
-      if( *pPgno==PENDING_BYTE_PAGE(pBt) ){
-        (*pPgno)++;
-      }
-    }
-    if( pBt->autoVacuum && PTRMAP_ISPAGE(pBt, *pPgno) ){
-      /* If *pPgno refers to a pointer-map page, allocate two new pages
-      ** at the end of the file instead of one. The first allocated page
-      ** becomes a new pointer-map page, the second is used by the caller.
-      */
-      TRACE(("ALLOCATE: %d from end of file (pointer-map page)\n", *pPgno));
-      assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
-      (*pPgno)++;
-      if( *pPgno==PENDING_BYTE_PAGE(pBt) ){ (*pPgno)++; }
-    }
-    if( pBt->nTrunc ){
-      pBt->nTrunc = *pPgno;
-    }
-#endif
 
-    assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
-    rc = sqlite3BtreeGetPage(pBt, *pPgno, ppPage, 0);
-    if( rc ) return rc;
-    rc = sqlite3PagerWrite((*ppPage)->pDbPage);
+  rc = btreeGetPage(pBt, pgno, ppPage, 0);
+  if( rc==SQLITE_OK ){
+    rc = btreeInitPage(*ppPage);
     if( rc!=SQLITE_OK ){
       releasePage(*ppPage);
     }
-    TRACE(("ALLOCATE: %d from end of file\n", *pPgno));
   }
 
-  assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
+  /* If the requested page number was either 0 or greater than the page
+  ** number of the last page in the database, this function should return
+  ** SQLITE_CORRUPT or some other error (i.e. SQLITE_FULL). Check that this
+  ** is the case.  */
+  assert( (pgno>0 && pgno<=iLastPg) || rc!=SQLITE_OK );
+  testcase( pgno==0 );
+  testcase( pgno==iLastPg );
 
-end_allocate_page:
-  releasePage(pTrunk);
-  releasePage(pPrevTrunk);
   return rc;
 }
 
 /*
-** Add a page of the database file to the freelist.
-**
-** sqlite3PagerUnref() is NOT called for pPage.
+** Release a MemPage.  This should be called once for each prior
+** call to btreeGetPage.
 */
-static int freePage(MemPage *pPage){
-  BtShared *pBt = pPage->pBt;
-  MemPage *pPage1 = pBt->pPage1;
-  int rc, n, k;
-
-  /* Prepare the page for freeing */
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  assert( pPage->pgno>1 );
-  pPage->isInit = 0;
-  releasePage(pPage->pParent);
-  pPage->pParent = 0;
-
-  /* Increment the free page count on pPage1 */
-  rc = sqlite3PagerWrite(pPage1->pDbPage);
-  if( rc ) return rc;
-  n = get4byte(&pPage1->aData[36]);
-  put4byte(&pPage1->aData[36], n+1);
-
-#ifdef SQLITE_SECURE_DELETE
-  /* If the SQLITE_SECURE_DELETE compile-time option is enabled, then
-  ** always fully overwrite deleted information with zeros.
-  */
-  rc = sqlite3PagerWrite(pPage->pDbPage);
-  if( rc ) return rc;
-  memset(pPage->aData, 0, pPage->pBt->pageSize);
-#endif
-
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  /* If the database supports auto-vacuum, write an entry in the pointer-map
-  ** to indicate that the page is free.
-  */
-  if( pBt->autoVacuum ){
-    rc = ptrmapPut(pBt, pPage->pgno, PTRMAP_FREEPAGE, 0);
-    if( rc ) return rc;
+static void releasePage(MemPage *pPage){
+  if( pPage ){
+    assert( pPage->nOverflow==0 || sqlite3PagerPageRefcount(pPage->pDbPage)>1 );
+    assert( pPage->aData );
+    assert( pPage->pBt );
+    assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
+    assert( sqlite3PagerGetData(pPage->pDbPage)==pPage->aData );
+    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+    sqlite3PagerUnref(pPage->pDbPage);
   }
-#endif
+}
 
-  if( n==0 ){
-    /* This is the first free page */
-    rc = sqlite3PagerWrite(pPage->pDbPage);
-    if( rc ) return rc;
-    memset(pPage->aData, 0, 8);
-    put4byte(&pPage1->aData[32], pPage->pgno);
-    TRACE(("FREE-PAGE: %d first\n", pPage->pgno));
-  }else{
-    /* Other free pages already exist.  Retrive the first trunk page
-    ** of the freelist and find out how many leaves it has. */
-    MemPage *pTrunk;
-    rc = sqlite3BtreeGetPage(pBt, get4byte(&pPage1->aData[32]), &pTrunk, 0);
-    if( rc ) return rc;
-    k = get4byte(&pTrunk->aData[4]);
-    if( k>=pBt->usableSize/4 - 8 ){
-      /* The trunk is full.  Turn the page being freed into a new
-      ** trunk page with no leaves. */
-      rc = sqlite3PagerWrite(pPage->pDbPage);
-      if( rc==SQLITE_OK ){
-        put4byte(pPage->aData, pTrunk->pgno);
-        put4byte(&pPage->aData[4], 0);
-        put4byte(&pPage1->aData[32], pPage->pgno);
-        TRACE(("FREE-PAGE: %d new trunk page replacing %d\n",
-                pPage->pgno, pTrunk->pgno));
-      }
-    }else if( k<0 ){
-      rc = SQLITE_CORRUPT;
-    }else{
-      /* Add the newly freed page as a leaf on the current trunk */
-      rc = sqlite3PagerWrite(pTrunk->pDbPage);
-      if( rc==SQLITE_OK ){
-        put4byte(&pTrunk->aData[4], k+1);
-        put4byte(&pTrunk->aData[8+k*4], pPage->pgno);
-#ifndef SQLITE_SECURE_DELETE
-        sqlite3PagerDontWrite(pPage->pDbPage);
-#endif
-      }
-      TRACE(("FREE-PAGE: %d leaf on trunk page %d\n",pPage->pgno,pTrunk->pgno));
+/*
+** During a rollback, when the pager reloads information into the cache
+** so that the cache is restored to its original state at the start of
+** the transaction, for each page restored this routine is called.
+**
+** This routine needs to reset the extra data section at the end of the
+** page to agree with the restored data.
+*/
+static void pageReinit(DbPage *pData){
+  MemPage *pPage;
+  pPage = (MemPage *)sqlite3PagerGetExtra(pData);
+  assert( sqlite3PagerPageRefcount(pData)>0 );
+  if( pPage->isInit ){
+    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+    pPage->isInit = 0;
+    if( sqlite3PagerPageRefcount(pData)>1 ){
+      /* pPage might not be a btree page;  it might be an overflow page
+      ** or ptrmap page or a free page.  In those cases, the following
+      ** call to btreeInitPage() will likely return SQLITE_CORRUPT.
+      ** But no harm is done by this.  And it is very important that
+      ** btreeInitPage() be called on every btree page so we make
+      ** the call for every page that comes in for re-initing. */
+      btreeInitPage(pPage);
     }
-    releasePage(pTrunk);
   }
-  return rc;
 }
 
 /*
-** Free any overflow pages associated with the given Cell.
+** Invoke the busy handler for a btree.
 */
-static int clearCell(MemPage *pPage, unsigned char *pCell){
-  BtShared *pBt = pPage->pBt;
-  CellInfo info;
-  Pgno ovflPgno;
-  int rc;
-  int nOvfl;
-  int ovflPageSize;
-
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-  if( info.iOverflow==0 ){
-    return SQLITE_OK;  /* No overflow pages. Return without doing anything */
-  }
-  ovflPgno = get4byte(&pCell[info.iOverflow]);
-  ovflPageSize = pBt->usableSize - 4;
-  nOvfl = (info.nPayload - info.nLocal + ovflPageSize - 1)/ovflPageSize;
-  assert( ovflPgno==0 || nOvfl>0 );
-  while( nOvfl-- ){
-    MemPage *pOvfl;
-    if( ovflPgno==0 || ovflPgno>sqlite3PagerPagecount(pBt->pPager) ){
-      return SQLITE_CORRUPT_BKPT;
-    }
-
-    rc = getOverflowPage(pBt, ovflPgno, &pOvfl, (nOvfl==0)?0:&ovflPgno);
-    if( rc ) return rc;
-    rc = freePage(pOvfl);
-    sqlite3PagerUnref(pOvfl->pDbPage);
-    if( rc ) return rc;
-  }
-  return SQLITE_OK;
+static int btreeInvokeBusyHandler(void *pArg){
+  BtShared *pBt = (BtShared*)pArg;
+  assert( pBt->db );
+  assert( sqlite3_mutex_held(pBt->db->mutex) );
+  return sqlite3InvokeBusyHandler(&pBt->db->busyHandler);
 }
 
 /*
-** Create the byte sequence used to represent a cell on page pPage
-** and write that byte sequence into pCell[].  Overflow pages are
-** allocated and filled in as necessary.  The calling procedure
-** is responsible for making sure sufficient space has been allocated
-** for pCell[].
+** Open a database file.
+** 
+** zFilename is the name of the database file.  If zFilename is NULL
+** a new database with a random name is created.  This randomly named
+** database file will be deleted when sqlite3BtreeClose() is called.
+** If zFilename is ":memory:" then an in-memory database is created
+** that is automatically destroyed when it is closed.
 **
-** Note that pCell does not necessary need to point to the pPage->aData
-** area.  pCell might point to some temporary storage.  The cell will
-** be constructed in this temporary area then copied into pPage->aData
-** later.
+** If the database is already opened in the same database connection
+** and we are in shared cache mode, then the open will fail with an
+** SQLITE_CONSTRAINT error.  We cannot allow two or more BtShared
+** objects in the same database connection since doing so will lead
+** to problems with locking.
 */
-static int fillInCell(
-  MemPage *pPage,                /* The page that contains the cell */
-  unsigned char *pCell,          /* Complete text of the cell */
-  const void *pKey, i64 nKey,    /* The key */
-  const void *pData,int nData,   /* The data */
-  int nZero,                     /* Extra zero bytes to append to pData */
-  int *pnSize                    /* Write cell size here */
+SQLITE_PRIVATE int sqlite3BtreeOpen(
+  const char *zFilename,  /* Name of the file containing the BTree database */
+  sqlite3 *db,            /* Associated database handle */
+  Btree **ppBtree,        /* Pointer to new Btree object written here */
+  int flags,              /* Options */
+  int vfsFlags            /* Flags passed through to sqlite3_vfs.xOpen() */
 ){
-  int nPayload;
-  const u8 *pSrc;
-  int nSrc, n, rc;
-  int spaceLeft;
-  MemPage *pOvfl = 0;
-  MemPage *pToRelease = 0;
-  unsigned char *pPrior;
-  unsigned char *pPayload;
-  BtShared *pBt = pPage->pBt;
-  Pgno pgnoOvfl = 0;
-  int nHeader;
-  CellInfo info;
+  sqlite3_vfs *pVfs;             /* The VFS to use for this btree */
+  BtShared *pBt = 0;             /* Shared part of btree structure */
+  Btree *p;                      /* Handle to return */
+  sqlite3_mutex *mutexOpen = 0;  /* Prevents a race condition. Ticket #3537 */
+  int rc = SQLITE_OK;            /* Result code from this function */
+  u8 nReserve;                   /* Byte of unused space on each page */
+  unsigned char zDbHeader[100];  /* Database header content */
 
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  /* Set the variable isMemdb to true for an in-memory database, or 
+  ** false for a file-based database. This symbol is only required if
+  ** either of the shared-data or autovacuum features are compiled 
+  ** into the library.
+  */
+#if !defined(SQLITE_OMIT_SHARED_CACHE) || !defined(SQLITE_OMIT_AUTOVACUUM)
+  #ifdef SQLITE_OMIT_MEMORYDB
+    const int isMemdb = 0;
+  #else
+    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
+  #endif
+#endif
 
-  /* Fill in the header. */
-  nHeader = 0;
-  if( !pPage->leaf ){
-    nHeader += 4;
-  }
-  if( pPage->hasData ){
-    nHeader += putVarint(&pCell[nHeader], nData+nZero);
-  }else{
-    nData = nZero = 0;
-  }
-  nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey);
-  sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-  assert( info.nHeader==nHeader );
-  assert( info.nKey==nKey );
-  assert( info.nData==nData+nZero );
-  
-  /* Fill in the payload */
-  nPayload = nData + nZero;
-  if( pPage->intKey ){
-    pSrc = pData;
-    nSrc = nData;
-    nData = 0;
-  }else{
-    nPayload += nKey;
-    pSrc = pKey;
-    nSrc = nKey;
+  assert( db!=0 );
+  assert( sqlite3_mutex_held(db->mutex) );
+
+  pVfs = db->pVfs;
+  p = sqlite3MallocZero(sizeof(Btree));
+  if( !p ){
+    return SQLITE_NOMEM;
   }
-  *pnSize = info.nSize;
-  spaceLeft = info.nLocal;
-  pPayload = &pCell[nHeader];
-  pPrior = &pCell[info.iOverflow];
+  p->inTrans = TRANS_NONE;
+  p->db = db;
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  p->lock.pBtree = p;
+  p->lock.iTable = 1;
+#endif
 
-  while( nPayload>0 ){
-    if( spaceLeft==0 ){
-      int isExact = 0;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      Pgno pgnoPtrmap = pgnoOvfl; /* Overflow page pointer-map entry page */
-      if( pBt->autoVacuum ){
-        do{
-          pgnoOvfl++;
-        } while( 
-          PTRMAP_ISPAGE(pBt, pgnoOvfl) || pgnoOvfl==PENDING_BYTE_PAGE(pBt) 
-        );
-        if( pgnoOvfl>1 ){
-          /* isExact = 1; */
-        }
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
+  /*
+  ** If this Btree is a candidate for shared cache, try to find an
+  ** existing BtShared object that we can share with
+  */
+  if( isMemdb==0 && zFilename && zFilename[0] ){
+    if( vfsFlags & SQLITE_OPEN_SHAREDCACHE ){
+      int nFullPathname = pVfs->mxPathname+1;
+      char *zFullPathname = sqlite3Malloc(nFullPathname);
+      sqlite3_mutex *mutexShared;
+      p->sharable = 1;
+      if( !zFullPathname ){
+        sqlite3_free(p);
+        return SQLITE_NOMEM;
+      }
+      sqlite3OsFullPathname(pVfs, zFilename, nFullPathname, zFullPathname);
+      mutexOpen = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_OPEN);
+      sqlite3_mutex_enter(mutexOpen);
+      mutexShared = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+      sqlite3_mutex_enter(mutexShared);
+      for(pBt=GLOBAL(BtShared*,sqlite3SharedCacheList); pBt; pBt=pBt->pNext){
+        assert( pBt->nRef>0 );
+        if( 0==strcmp(zFullPathname, sqlite3PagerFilename(pBt->pPager))
+                 && sqlite3PagerVfs(pBt->pPager)==pVfs ){
+          int iDb;
+          for(iDb=db->nDb-1; iDb>=0; iDb--){
+            Btree *pExisting = db->aDb[iDb].pBt;
+            if( pExisting && pExisting->pBt==pBt ){
+              sqlite3_mutex_leave(mutexShared);
+              sqlite3_mutex_leave(mutexOpen);
+              sqlite3_free(zFullPathname);
+              sqlite3_free(p);
+              return SQLITE_CONSTRAINT;
+            }
+          }
+          p->pBt = pBt;
+          pBt->nRef++;
+          break;
+        }
       }
+      sqlite3_mutex_leave(mutexShared);
+      sqlite3_free(zFullPathname);
+    }
+#ifdef SQLITE_DEBUG
+    else{
+      /* In debug mode, we mark all persistent databases as sharable
+      ** even when they are not.  This exercises the locking code and
+      ** gives more opportunity for asserts(sqlite3_mutex_held())
+      ** statements to find locking problems.
+      */
+      p->sharable = 1;
+    }
 #endif
-      rc = allocateBtreePage(pBt, &pOvfl, &pgnoOvfl, pgnoOvfl, isExact);
+  }
+#endif
+  if( pBt==0 ){
+    /*
+    ** The following asserts make sure that structures used by the btree are
+    ** the right size.  This is to guard against size changes that result
+    ** when compiling on a different architecture.
+    */
+    assert( sizeof(i64)==8 || sizeof(i64)==4 );
+    assert( sizeof(u64)==8 || sizeof(u64)==4 );
+    assert( sizeof(u32)==4 );
+    assert( sizeof(u16)==2 );
+    assert( sizeof(Pgno)==4 );
+  
+    pBt = sqlite3MallocZero( sizeof(*pBt) );
+    if( pBt==0 ){
+      rc = SQLITE_NOMEM;
+      goto btree_open_out;
+    }
+    rc = sqlite3PagerOpen(pVfs, &pBt->pPager, zFilename,
+                          EXTRA_SIZE, flags, vfsFlags, pageReinit);
+    if( rc==SQLITE_OK ){
+      rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
+    }
+    if( rc!=SQLITE_OK ){
+      goto btree_open_out;
+    }
+    pBt->db = db;
+    sqlite3PagerSetBusyhandler(pBt->pPager, btreeInvokeBusyHandler, pBt);
+    p->pBt = pBt;
+  
+    pBt->pCursor = 0;
+    pBt->pPage1 = 0;
+    pBt->readOnly = sqlite3PagerIsreadonly(pBt->pPager);
+    pBt->pageSize = get2byte(&zDbHeader[16]);
+    if( pBt->pageSize<512 || pBt->pageSize>SQLITE_MAX_PAGE_SIZE
+         || ((pBt->pageSize-1)&pBt->pageSize)!=0 ){
+      pBt->pageSize = 0;
 #ifndef SQLITE_OMIT_AUTOVACUUM
-      /* If the database supports auto-vacuum, and the second or subsequent
-      ** overflow page is being allocated, add an entry to the pointer-map
-      ** for that page now. 
-      **
-      ** If this is the first overflow page, then write a partial entry 
-      ** to the pointer-map. If we write nothing to this pointer-map slot,
-      ** then the optimistic overflow chain processing in clearCell()
-      ** may misinterpret the uninitialised values and delete the
-      ** wrong pages from the database.
+      /* If the magic name ":memory:" will create an in-memory database, then
+      ** leave the autoVacuum mode at 0 (do not auto-vacuum), even if
+      ** SQLITE_DEFAULT_AUTOVACUUM is true. On the other hand, if
+      ** SQLITE_OMIT_MEMORYDB has been defined, then ":memory:" is just a
+      ** regular file-name. In this case the auto-vacuum applies as per normal.
       */
-      if( pBt->autoVacuum && rc==SQLITE_OK ){
-        u8 eType = (pgnoPtrmap?PTRMAP_OVERFLOW2:PTRMAP_OVERFLOW1);
-        rc = ptrmapPut(pBt, pgnoOvfl, eType, pgnoPtrmap);
-        if( rc ){
-          releasePage(pOvfl);
-        }
+      if( zFilename && !isMemdb ){
+        pBt->autoVacuum = (SQLITE_DEFAULT_AUTOVACUUM ? 1 : 0);
+        pBt->incrVacuum = (SQLITE_DEFAULT_AUTOVACUUM==2 ? 1 : 0);
       }
 #endif
-      if( rc ){
-        releasePage(pToRelease);
-        return rc;
+      nReserve = 0;
+    }else{
+      nReserve = zDbHeader[20];
+      pBt->pageSizeFixed = 1;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      pBt->autoVacuum = (get4byte(&zDbHeader[36 + 4*4])?1:0);
+      pBt->incrVacuum = (get4byte(&zDbHeader[36 + 7*4])?1:0);
+#endif
+    }
+    rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
+    if( rc ) goto btree_open_out;
+    pBt->usableSize = pBt->pageSize - nReserve;
+    assert( (pBt->pageSize & 7)==0 );  /* 8-byte alignment of pageSize */
+   
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
+    /* Add the new BtShared object to the linked list sharable BtShareds.
+    */
+    if( p->sharable ){
+      sqlite3_mutex *mutexShared;
+      pBt->nRef = 1;
+      mutexShared = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+      if( SQLITE_THREADSAFE && sqlite3GlobalConfig.bCoreMutex ){
+        pBt->mutex = sqlite3MutexAlloc(SQLITE_MUTEX_FAST);
+        if( pBt->mutex==0 ){
+          rc = SQLITE_NOMEM;
+          db->mallocFailed = 0;
+          goto btree_open_out;
+        }
       }
-      put4byte(pPrior, pgnoOvfl);
-      releasePage(pToRelease);
-      pToRelease = pOvfl;
-      pPrior = pOvfl->aData;
-      put4byte(pPrior, 0);
-      pPayload = &pOvfl->aData[4];
-      spaceLeft = pBt->usableSize - 4;
+      sqlite3_mutex_enter(mutexShared);
+      pBt->pNext = GLOBAL(BtShared*,sqlite3SharedCacheList);
+      GLOBAL(BtShared*,sqlite3SharedCacheList) = pBt;
+      sqlite3_mutex_leave(mutexShared);
     }
-    n = nPayload;
-    if( n>spaceLeft ) n = spaceLeft;
-    if( nSrc>0 ){
-      if( n>nSrc ) n = nSrc;
-      assert( pSrc );
-      memcpy(pPayload, pSrc, n);
-    }else{
-      memset(pPayload, 0, n);
+#endif
+  }
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
+  /* If the new Btree uses a sharable pBtShared, then link the new
+  ** Btree into the list of all sharable Btrees for the same connection.
+  ** The list is kept in ascending order by pBt address.
+  */
+  if( p->sharable ){
+    int i;
+    Btree *pSib;
+    for(i=0; i<db->nDb; i++){
+      if( (pSib = db->aDb[i].pBt)!=0 && pSib->sharable ){
+        while( pSib->pPrev ){ pSib = pSib->pPrev; }
+        if( p->pBt<pSib->pBt ){
+          p->pNext = pSib;
+          p->pPrev = 0;
+          pSib->pPrev = p;
+        }else{
+          while( pSib->pNext && pSib->pNext->pBt<p->pBt ){
+            pSib = pSib->pNext;
+          }
+          p->pNext = pSib->pNext;
+          p->pPrev = pSib;
+          if( p->pNext ){
+            p->pNext->pPrev = p;
+          }
+          pSib->pNext = p;
+        }
+        break;
+      }
     }
-    nPayload -= n;
-    pPayload += n;
-    pSrc += n;
-    nSrc -= n;
-    spaceLeft -= n;
-    if( nSrc==0 ){
-      nSrc = nData;
-      pSrc = pData;
+  }
+#endif
+  *ppBtree = p;
+
+btree_open_out:
+  if( rc!=SQLITE_OK ){
+    if( pBt && pBt->pPager ){
+      sqlite3PagerClose(pBt->pPager);
     }
+    sqlite3_free(pBt);
+    sqlite3_free(p);
+    *ppBtree = 0;
   }
-  releasePage(pToRelease);
-  return SQLITE_OK;
+  if( mutexOpen ){
+    assert( sqlite3_mutex_held(mutexOpen) );
+    sqlite3_mutex_leave(mutexOpen);
+  }
+  return rc;
 }
 
 /*
-** Change the MemPage.pParent pointer on the page whose number is
-** given in the second argument so that MemPage.pParent holds the
-** pointer in the third argument.
+** Decrement the BtShared.nRef counter.  When it reaches zero,
+** remove the BtShared structure from the sharing list.  Return
+** true if the BtShared.nRef counter reaches zero and return
+** false if it is still positive.
 */
-static int reparentPage(BtShared *pBt, Pgno pgno, MemPage *pNewParent, int idx){
-  MemPage *pThis;
-  DbPage *pDbPage;
+static int removeFromSharingList(BtShared *pBt){
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  sqlite3_mutex *pMaster;
+  BtShared *pList;
+  int removed = 0;
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( pNewParent!=0 );
-  if( pgno==0 ) return SQLITE_OK;
-  assert( pBt->pPager!=0 );
-  pDbPage = sqlite3PagerLookup(pBt->pPager, pgno);
-  if( pDbPage ){
-    pThis = (MemPage *)sqlite3PagerGetExtra(pDbPage);
-    if( pThis->isInit ){
-      assert( pThis->aData==sqlite3PagerGetData(pDbPage) );
-      if( pThis->pParent!=pNewParent ){
-        if( pThis->pParent ) sqlite3PagerUnref(pThis->pParent->pDbPage);
-        pThis->pParent = pNewParent;
-        sqlite3PagerRef(pNewParent->pDbPage);
+  assert( sqlite3_mutex_notheld(pBt->mutex) );
+  pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+  sqlite3_mutex_enter(pMaster);
+  pBt->nRef--;
+  if( pBt->nRef<=0 ){
+    if( GLOBAL(BtShared*,sqlite3SharedCacheList)==pBt ){
+      GLOBAL(BtShared*,sqlite3SharedCacheList) = pBt->pNext;
+    }else{
+      pList = GLOBAL(BtShared*,sqlite3SharedCacheList);
+      while( ALWAYS(pList) && pList->pNext!=pBt ){
+        pList=pList->pNext;
+      }
+      if( ALWAYS(pList) ){
+        pList->pNext = pBt->pNext;
       }
-      pThis->idxParent = idx;
     }
-    sqlite3PagerUnref(pDbPage);
-  }
-
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  if( pBt->autoVacuum ){
-    return ptrmapPut(pBt, pgno, PTRMAP_BTREE, pNewParent->pgno);
+    if( SQLITE_THREADSAFE ){
+      sqlite3_mutex_free(pBt->mutex);
+    }
+    removed = 1;
   }
+  sqlite3_mutex_leave(pMaster);
+  return removed;
+#else
+  return 1;
 #endif
-  return SQLITE_OK;
 }
 
-
-
 /*
-** Change the pParent pointer of all children of pPage to point back
-** to pPage.
-**
-** In other words, for every child of pPage, invoke reparentPage()
-** to make sure that each child knows that pPage is its parent.
-**
-** This routine gets called after you memcpy() one page into
-** another.
+** Make sure pBt->pTmpSpace points to an allocation of 
+** MX_CELL_SIZE(pBt) bytes.
 */
-static int reparentChildPages(MemPage *pPage){
-  int i;
-  BtShared *pBt = pPage->pBt;
-  int rc = SQLITE_OK;
-
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( pPage->leaf ) return SQLITE_OK;
-
-  for(i=0; i<pPage->nCell; i++){
-    u8 *pCell = findCell(pPage, i);
-    rc = reparentPage(pBt, get4byte(pCell), pPage, i);
-    if( rc!=SQLITE_OK ) return rc;
+static void allocateTempSpace(BtShared *pBt){
+  if( !pBt->pTmpSpace ){
+    pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );
   }
-  rc = reparentPage(pBt, get4byte(&pPage->aData[pPage->hdrOffset+8]), 
-                    pPage, i);
-  pPage->idxShift = 0;
-  return rc;
 }
 
 /*
-** Remove the i-th cell from pPage.  This routine effects pPage only.
-** The cell content is not freed or deallocated.  It is assumed that
-** the cell content has been copied someplace else.  This routine just
-** removes the reference to the cell from pPage.
-**
-** "sz" must be the number of bytes in the cell.
+** Free the pBt->pTmpSpace allocation
 */
-static void dropCell(MemPage *pPage, int idx, int sz){
-  int i;          /* Loop counter */
-  int pc;         /* Offset to cell content of cell being deleted */
-  u8 *data;       /* pPage->aData */
-  u8 *ptr;        /* Used to move bytes around within data[] */
-
-  assert( idx>=0 && idx<pPage->nCell );
-  assert( sz==cellSize(pPage, idx) );
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  data = pPage->aData;
-  ptr = &data[pPage->cellOffset + 2*idx];
-  pc = get2byte(ptr);
-  assert( pc>10 && pc+sz<=pPage->pBt->usableSize );
-  freeSpace(pPage, pc, sz);
-  for(i=idx+1; i<pPage->nCell; i++, ptr+=2){
-    ptr[0] = ptr[2];
-    ptr[1] = ptr[3];
-  }
-  pPage->nCell--;
-  put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
-  pPage->nFree += 2;
-  pPage->idxShift = 1;
+static void freeTempSpace(BtShared *pBt){
+  sqlite3PageFree( pBt->pTmpSpace);
+  pBt->pTmpSpace = 0;
 }
 
 /*
-** Insert a new cell on pPage at cell index "i".  pCell points to the
-** content of the cell.
-**
-** If the cell content will fit on the page, then put it there.  If it
-** will not fit, then make a copy of the cell content into pTemp if
-** pTemp is not null.  Regardless of pTemp, allocate a new entry
-** in pPage->aOvfl[] and make it point to the cell content (either
-** in pTemp or the original pCell) and also record its index. 
-** Allocating a new entry in pPage->aCell[] implies that 
-** pPage->nOverflow is incremented.
-**
-** If nSkip is non-zero, then do not copy the first nSkip bytes of the
-** cell. The caller will overwrite them after this function returns. If
-** nSkip is non-zero, then pCell may not point to an invalid memory location 
-** (but pCell+nSkip is always valid).
+** Close an open database and invalidate all cursors.
 */
-static int insertCell(
-  MemPage *pPage,   /* Page into which we are copying */
-  int i,            /* New cell becomes the i-th cell of the page */
-  u8 *pCell,        /* Content of the new cell */
-  int sz,           /* Bytes of content in pCell */
-  u8 *pTemp,        /* Temp storage space for pCell, if needed */
-  u8 nSkip          /* Do not write the first nSkip bytes of the cell */
-){
-  int idx;          /* Where to write new cell content in data[] */
-  int j;            /* Loop counter */
-  int top;          /* First byte of content for any cell in data[] */
-  int end;          /* First byte past the last cell pointer in data[] */
-  int ins;          /* Index in data[] where new cell pointer is inserted */
-  int hdr;          /* Offset into data[] of the page header */
-  int cellOffset;   /* Address of first cell pointer in data[] */
-  u8 *data;         /* The content of the whole page */
-  u8 *ptr;          /* Used for moving information around in data[] */
+SQLITE_PRIVATE int sqlite3BtreeClose(Btree *p){
+  BtShared *pBt = p->pBt;
+  BtCursor *pCur;
 
-  assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
-  assert( sz==cellSizePtr(pPage, pCell) );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( pPage->nOverflow || sz+2>pPage->nFree ){
-    if( pTemp ){
-      memcpy(pTemp+nSkip, pCell+nSkip, sz-nSkip);
-      pCell = pTemp;
-    }
-    j = pPage->nOverflow++;
-    assert( j<sizeof(pPage->aOvfl)/sizeof(pPage->aOvfl[0]) );
-    pPage->aOvfl[j].pCell = pCell;
-    pPage->aOvfl[j].idx = i;
-    pPage->nFree = 0;
-  }else{
-    int rc = sqlite3PagerWrite(pPage->pDbPage);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    assert( sqlite3PagerIswriteable(pPage->pDbPage) );
-    data = pPage->aData;
-    hdr = pPage->hdrOffset;
-    top = get2byte(&data[hdr+5]);
-    cellOffset = pPage->cellOffset;
-    end = cellOffset + 2*pPage->nCell + 2;
-    ins = cellOffset + 2*i;
-    if( end > top - sz ){
-      rc = defragmentPage(pPage);
-      if( rc!=SQLITE_OK ) return rc;
-      top = get2byte(&data[hdr+5]);
-      assert( end + sz <= top );
-    }
-    idx = allocateSpace(pPage, sz);
-    assert( idx>0 );
-    assert( end <= get2byte(&data[hdr+5]) );
-    pPage->nCell++;
-    pPage->nFree -= 2;
-    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
-    for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
-      ptr[0] = ptr[-2];
-      ptr[1] = ptr[-1];
+  /* Close all cursors opened via this handle.  */
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  sqlite3BtreeEnter(p);
+  pCur = pBt->pCursor;
+  while( pCur ){
+    BtCursor *pTmp = pCur;
+    pCur = pCur->pNext;
+    if( pTmp->pBtree==p ){
+      sqlite3BtreeCloseCursor(pTmp);
     }
-    put2byte(&data[ins], idx);
-    put2byte(&data[hdr+3], pPage->nCell);
-    pPage->idxShift = 1;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pPage->pBt->autoVacuum ){
-      /* The cell may contain a pointer to an overflow page. If so, write
-      ** the entry for the overflow page into the pointer map.
-      */
-      CellInfo info;
-      sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-      assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
-      if( (info.nData+(pPage->intKey?0:info.nKey))>info.nLocal ){
-        Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
-        rc = ptrmapPut(pPage->pBt, pgnoOvfl, PTRMAP_OVERFLOW1, pPage->pgno);
-        if( rc!=SQLITE_OK ) return rc;
-      }
+  }
+
+  /* Rollback any active transaction and free the handle structure.
+  ** The call to sqlite3BtreeRollback() drops any table-locks held by
+  ** this handle.
+  */
+  sqlite3BtreeRollback(p);
+  sqlite3BtreeLeave(p);
+
+  /* If there are still other outstanding references to the shared-btree
+  ** structure, return now. The remainder of this procedure cleans 
+  ** up the shared-btree.
+  */
+  assert( p->wantToLock==0 && p->locked==0 );
+  if( !p->sharable || removeFromSharingList(pBt) ){
+    /* The pBt is no longer on the sharing list, so we can access
+    ** it without having to hold the mutex.
+    **
+    ** Clean out and delete the BtShared object.
+    */
+    assert( !pBt->pCursor );
+    sqlite3PagerClose(pBt->pPager);
+    if( pBt->xFreeSchema && pBt->pSchema ){
+      pBt->xFreeSchema(pBt->pSchema);
     }
-#endif
+    sqlite3_free(pBt->pSchema);
+    freeTempSpace(pBt);
+    sqlite3_free(pBt);
   }
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  assert( p->wantToLock==0 );
+  assert( p->locked==0 );
+  if( p->pPrev ) p->pPrev->pNext = p->pNext;
+  if( p->pNext ) p->pNext->pPrev = p->pPrev;
+#endif
+
+  sqlite3_free(p);
   return SQLITE_OK;
 }
 
 /*
-** Add a list of cells to a page.  The page should be initially empty.
-** The cells are guaranteed to fit on the page.
+** Change the limit on the number of pages allowed in the cache.
+**
+** The maximum number of cache pages is set to the absolute
+** value of mxPage.  If mxPage is negative, the pager will
+** operate asynchronously - it will not stop to do fsync()s
+** to insure data is written to the disk surface before
+** continuing.  Transactions still work if synchronous is off,
+** and the database cannot be corrupted if this program
+** crashes.  But if the operating system crashes or there is
+** an abrupt power failure when synchronous is off, the database
+** could be left in an inconsistent and unrecoverable state.
+** Synchronous is on by default so database corruption is not
+** normally a worry.
 */
-static void assemblePage(
-  MemPage *pPage,   /* The page to be assemblied */
-  int nCell,        /* The number of cells to add to this page */
-  u8 **apCell,      /* Pointers to cell bodies */
-  u16 *aSize        /* Sizes of the cells */
-){
-  int i;            /* Loop counter */
-  int totalSize;    /* Total size of all cells */
-  int hdr;          /* Index of page header */
-  int cellptr;      /* Address of next cell pointer */
-  int cellbody;     /* Address of next cell body */
-  u8 *data;         /* Data for the page */
-
-  assert( pPage->nOverflow==0 );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  totalSize = 0;
-  for(i=0; i<nCell; i++){
-    totalSize += aSize[i];
-  }
-  assert( totalSize+2*nCell<=pPage->nFree );
-  assert( pPage->nCell==0 );
-  cellptr = pPage->cellOffset;
-  data = pPage->aData;
-  hdr = pPage->hdrOffset;
-  put2byte(&data[hdr+3], nCell);
-  if( nCell ){
-    cellbody = allocateSpace(pPage, totalSize);
-    assert( cellbody>0 );
-    assert( pPage->nFree >= 2*nCell );
-    pPage->nFree -= 2*nCell;
-    for(i=0; i<nCell; i++){
-      put2byte(&data[cellptr], cellbody);
-      memcpy(&data[cellbody], apCell[i], aSize[i]);
-      cellptr += 2;
-      cellbody += aSize[i];
-    }
-    assert( cellbody==pPage->pBt->usableSize );
-  }
-  pPage->nCell = nCell;
+SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
+  BtShared *pBt = p->pBt;
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  sqlite3BtreeEnter(p);
+  sqlite3PagerSetCachesize(pBt->pPager, mxPage);
+  sqlite3BtreeLeave(p);
+  return SQLITE_OK;
 }
 
 /*
-** The following parameters determine how many adjacent pages get involved
-** in a balancing operation.  NN is the number of neighbors on either side
-** of the page that participate in the balancing operation.  NB is the
-** total number of pages that participate, including the target page and
-** NN neighbors on either side.
-**
-** The minimum value of NN is 1 (of course).  Increasing NN above 1
-** (to 2 or 3) gives a modest improvement in SELECT and DELETE performance
-** in exchange for a larger degradation in INSERT and UPDATE performance.
-** The value of NN appears to give the best results overall.
+** Change the way data is synced to disk in order to increase or decrease
+** how well the database resists damage due to OS crashes and power
+** failures.  Level 1 is the same as asynchronous (no syncs() occur and
+** there is a high probability of damage)  Level 2 is the default.  There
+** is a very low but non-zero probability of damage.  Level 3 reduces the
+** probability of damage to near zero but with a write performance reduction.
 */
-#define NN 1             /* Number of neighbors on either side of pPage */
-#define NB (NN*2+1)      /* Total pages involved in the balance */
-
-/* Forward reference */
-static int balance(MemPage*, int);
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree *p, int level, int fullSync){
+  BtShared *pBt = p->pBt;
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  sqlite3BtreeEnter(p);
+  sqlite3PagerSetSafetyLevel(pBt->pPager, level, fullSync);
+  sqlite3BtreeLeave(p);
+  return SQLITE_OK;
+}
+#endif
 
-#ifndef SQLITE_OMIT_QUICKBALANCE
 /*
-** This version of balance() handles the common special case where
-** a new entry is being inserted on the extreme right-end of the
-** tree, in other words, when the new entry will become the largest
-** entry in the tree.
-**
-** Instead of trying balance the 3 right-most leaf pages, just add
-** a new page to the right-hand side and put the one new entry in
-** that page.  This leaves the right side of the tree somewhat
-** unbalanced.  But odds are that we will be inserting new entries
-** at the end soon afterwards so the nearly empty page will quickly
-** fill up.  On average.
-**
-** pPage is the leaf page which is the right-most page in the tree.
-** pParent is its parent.  pPage must have a single overflow entry
-** which is also the right-most entry on the page.
+** Return TRUE if the given btree is set to safety level 1.  In other
+** words, return TRUE if no sync() occurs on the disk files.
 */
-static int balance_quick(MemPage *pPage, MemPage *pParent){
+SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree *p){
+  BtShared *pBt = p->pBt;
   int rc;
-  MemPage *pNew;
-  Pgno pgnoNew;
-  u8 *pCell;
-  u16 szCell;
-  CellInfo info;
-  BtShared *pBt = pPage->pBt;
-  int parentIdx = pParent->nCell;   /* pParent new divider cell index */
-  int parentSize;                   /* Size of new divider cell */
-  u8 parentCell[64];                /* Space for the new divider cell */
-
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-
-  /* Allocate a new page. Insert the overflow cell from pPage
-  ** into it. Then remove the overflow cell from pPage.
-  */
-  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  pCell = pPage->aOvfl[0].pCell;
-  szCell = cellSizePtr(pPage, pCell);
-  zeroPage(pNew, pPage->aData[0]);
-  assemblePage(pNew, 1, &pCell, &szCell);
-  pPage->nOverflow = 0;
-
-  /* Set the parent of the newly allocated page to pParent. */
-  pNew->pParent = pParent;
-  sqlite3PagerRef(pParent->pDbPage);
-
-  /* pPage is currently the right-child of pParent. Change this
-  ** so that the right-child is the new page allocated above and
-  ** pPage is the next-to-right child. 
-  */
-  assert( pPage->nCell>0 );
-  pCell = findCell(pPage, pPage->nCell-1);
-  sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-  rc = fillInCell(pParent, parentCell, 0, info.nKey, 0, 0, 0, &parentSize);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  assert( parentSize<64 );
-  rc = insertCell(pParent, parentIdx, parentCell, parentSize, 0, 4);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-  put4byte(findOverflowCell(pParent,parentIdx), pPage->pgno);
-  put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew);
-
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  /* If this is an auto-vacuum database, update the pointer map
-  ** with entries for the new page, and any pointer from the 
-  ** cell on the page to an overflow page.
-  */
-  if( pBt->autoVacuum ){
-    rc = ptrmapPut(pBt, pgnoNew, PTRMAP_BTREE, pParent->pgno);
-    if( rc==SQLITE_OK ){
-      rc = ptrmapPutOvfl(pNew, 0);
-    }
-    if( rc!=SQLITE_OK ){
-      releasePage(pNew);
-      return rc;
-    }
-  }
-#endif
-
-  /* Release the reference to the new page and balance the parent page,
-  ** in case the divider cell inserted caused it to become overfull.
-  */
-  releasePage(pNew);
-  return balance(pParent, 0);
+  assert( sqlite3_mutex_held(p->db->mutex) );  
+  sqlite3BtreeEnter(p);
+  assert( pBt && pBt->pPager );
+  rc = sqlite3PagerNosync(pBt->pPager);
+  sqlite3BtreeLeave(p);
+  return rc;
 }
-#endif /* SQLITE_OMIT_QUICKBALANCE */
 
+#if !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM)
 /*
-** This routine redistributes Cells on pPage and up to NN*2 siblings
-** of pPage so that all pages have about the same amount of free space.
-** Usually NN siblings on either side of pPage is used in the balancing,
-** though more siblings might come from one side if pPage is the first
-** or last child of its parent.  If pPage has fewer than 2*NN siblings
-** (something which can only happen if pPage is the root page or a 
-** child of root) then all available siblings participate in the balancing.
-**
-** The number of siblings of pPage might be increased or decreased by one or
-** two in an effort to keep pages nearly full but not over full. The root page
-** is special and is allowed to be nearly empty. If pPage is 
-** the root page, then the depth of the tree might be increased
-** or decreased by one, as necessary, to keep the root page from being
-** overfull or completely empty.
+** Change the default pages size and the number of reserved bytes per page.
+** Or, if the page size has already been fixed, return SQLITE_READONLY 
+** without changing anything.
 **
-** Note that when this routine is called, some of the Cells on pPage
-** might not actually be stored in pPage->aData[].  This can happen
-** if the page is overfull.  Part of the job of this routine is to
-** make sure all Cells for pPage once again fit in pPage->aData[].
+** The page size must be a power of 2 between 512 and 65536.  If the page
+** size supplied does not meet this constraint then the page size is not
+** changed.
 **
-** In the course of balancing the siblings of pPage, the parent of pPage
-** might become overfull or underfull.  If that happens, then this routine
-** is called recursively on the parent.
+** Page sizes are constrained to be a power of two so that the region
+** of the database file used for locking (beginning at PENDING_BYTE,
+** the first byte past the 1GB boundary, 0x40000000) needs to occur
+** at the beginning of a page.
 **
-** If this routine fails for any reason, it might leave the database
-** in a corrupted state.  So if this routine fails, the database should
-** be rolled back.
+** If parameter nReserve is less than zero, then the number of reserved
+** bytes per page is left unchanged.
+**
+** If the iFix!=0 then the pageSizeFixed flag is set so that the page size
+** and autovacuum mode can no longer be changed.
 */
-static int balance_nonroot(MemPage *pPage){
-  MemPage *pParent;            /* The parent of pPage */
-  BtShared *pBt;               /* The whole database */
-  int nCell = 0;               /* Number of cells in apCell[] */
-  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
-  int nOld;                    /* Number of pages in apOld[] */
-  int nNew;                    /* Number of pages in apNew[] */
-  int nDiv;                    /* Number of cells in apDiv[] */
-  int i, j, k;                 /* Loop counters */
-  int idx;                     /* Index of pPage in pParent->aCell[] */
-  int nxDiv;                   /* Next divider slot in pParent->aCell[] */
-  int rc;                      /* The return code */
-  int leafCorrection;          /* 4 if pPage is a leaf.  0 if not */
-  int leafData;                /* True if pPage is a leaf of a LEAFDATA tree */
-  int usableSpace;             /* Bytes in pPage beyond the header */
-  int pageFlags;               /* Value of pPage->aData[0] */
-  int subtotal;                /* Subtotal of bytes in cells on one page */
-  int iSpace = 0;              /* First unused byte of aSpace[] */
-  MemPage *apOld[NB];          /* pPage and up to two siblings */
-  Pgno pgnoOld[NB];            /* Page numbers for each page in apOld[] */
-  MemPage *apCopy[NB];         /* Private copies of apOld[] pages */
-  MemPage *apNew[NB+2];        /* pPage and up to NB siblings after balancing */
-  Pgno pgnoNew[NB+2];          /* Page numbers for each page in apNew[] */
-  u8 *apDiv[NB];               /* Divider cells in pParent */
-  int cntNew[NB+2];            /* Index in aCell[] of cell after i-th page */
-  int szNew[NB+2];             /* Combined size of cells place on i-th page */
-  u8 **apCell = 0;             /* All cells begin balanced */
-  u16 *szCell;                 /* Local size of all cells in apCell[] */
-  u8 *aCopy[NB];               /* Space for holding data of apCopy[] */
-  u8 *aSpace;                  /* Space to hold copies of dividers cells */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  u8 *aFrom = 0;
-#endif
+SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int pageSize, int nReserve, int iFix){
+  int rc = SQLITE_OK;
+  BtShared *pBt = p->pBt;
+  assert( nReserve>=-1 && nReserve<=255 );
+  sqlite3BtreeEnter(p);
+  if( pBt->pageSizeFixed ){
+    sqlite3BtreeLeave(p);
+    return SQLITE_READONLY;
+  }
+  if( nReserve<0 ){
+    nReserve = pBt->pageSize - pBt->usableSize;
+  }
+  assert( nReserve>=0 && nReserve<=255 );
+  if( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE &&
+        ((pageSize-1)&pageSize)==0 ){
+    assert( (pageSize & 7)==0 );
+    assert( !pBt->pPage1 && !pBt->pCursor );
+    pBt->pageSize = (u16)pageSize;
+    freeTempSpace(pBt);
+  }
+  rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
+  pBt->usableSize = pBt->pageSize - (u16)nReserve;
+  if( iFix ) pBt->pageSizeFixed = 1;
+  sqlite3BtreeLeave(p);
+  return rc;
+}
 
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+/*
+** Return the currently defined page size
+*/
+SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree *p){
+  return p->pBt->pageSize;
+}
 
-  /* 
-  ** Find the parent page.
-  */
-  assert( pPage->isInit );
-  assert( sqlite3PagerIswriteable(pPage->pDbPage) || pPage->nOverflow==1 );
-  pBt = pPage->pBt;
-  pParent = pPage->pParent;
-  assert( pParent );
-  if( SQLITE_OK!=(rc = sqlite3PagerWrite(pParent->pDbPage)) ){
-    return rc;
-  }
-  TRACE(("BALANCE: begin page %d child of %d\n", pPage->pgno, pParent->pgno));
+/*
+** Return the number of bytes of space at the end of every page that
+** are intentually left unused.  This is the "reserved" space that is
+** sometimes used by extensions.
+*/
+SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree *p){
+  int n;
+  sqlite3BtreeEnter(p);
+  n = p->pBt->pageSize - p->pBt->usableSize;
+  sqlite3BtreeLeave(p);
+  return n;
+}
 
-#ifndef SQLITE_OMIT_QUICKBALANCE
-  /*
-  ** A special case:  If a new entry has just been inserted into a
-  ** table (that is, a btree with integer keys and all data at the leaves)
-  ** and the new entry is the right-most entry in the tree (it has the
-  ** largest key) then use the special balance_quick() routine for
-  ** balancing.  balance_quick() is much faster and results in a tighter
-  ** packing of data in the common case.
-  */
-  if( pPage->leaf &&
-      pPage->intKey &&
-      pPage->leafData &&
-      pPage->nOverflow==1 &&
-      pPage->aOvfl[0].idx==pPage->nCell &&
-      pPage->pParent->pgno!=1 &&
-      get4byte(&pParent->aData[pParent->hdrOffset+8])==pPage->pgno
-  ){
-    /*
-    ** TODO: Check the siblings to the left of pPage. It may be that
-    ** they are not full and no new page is required.
-    */
-    return balance_quick(pPage, pParent);
+/*
+** Set the maximum page count for a database if mxPage is positive.
+** No changes are made if mxPage is 0 or negative.
+** Regardless of the value of mxPage, return the maximum page count.
+*/
+SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree *p, int mxPage){
+  int n;
+  sqlite3BtreeEnter(p);
+  n = sqlite3PagerMaxPageCount(p->pBt->pPager, mxPage);
+  sqlite3BtreeLeave(p);
+  return n;
+}
+#endif /* !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM) */
+
+/*
+** Change the 'auto-vacuum' property of the database. If the 'autoVacuum'
+** parameter is non-zero, then auto-vacuum mode is enabled. If zero, it
+** is disabled. The default value for the auto-vacuum property is 
+** determined by the SQLITE_DEFAULT_AUTOVACUUM macro.
+*/
+SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *p, int autoVacuum){
+#ifdef SQLITE_OMIT_AUTOVACUUM
+  return SQLITE_READONLY;
+#else
+  BtShared *pBt = p->pBt;
+  int rc = SQLITE_OK;
+  u8 av = (u8)autoVacuum;
+
+  sqlite3BtreeEnter(p);
+  if( pBt->pageSizeFixed && (av ?1:0)!=pBt->autoVacuum ){
+    rc = SQLITE_READONLY;
+  }else{
+    pBt->autoVacuum = av ?1:0;
+    pBt->incrVacuum = av==2 ?1:0;
   }
+  sqlite3BtreeLeave(p);
+  return rc;
 #endif
+}
 
-  if( SQLITE_OK!=(rc = sqlite3PagerWrite(pPage->pDbPage)) ){
-    return rc;
-  }
+/*
+** Return the value of the 'auto-vacuum' property. If auto-vacuum is 
+** enabled 1 is returned. Otherwise 0.
+*/
+SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *p){
+#ifdef SQLITE_OMIT_AUTOVACUUM
+  return BTREE_AUTOVACUUM_NONE;
+#else
+  int rc;
+  sqlite3BtreeEnter(p);
+  rc = (
+    (!p->pBt->autoVacuum)?BTREE_AUTOVACUUM_NONE:
+    (!p->pBt->incrVacuum)?BTREE_AUTOVACUUM_FULL:
+    BTREE_AUTOVACUUM_INCR
+  );
+  sqlite3BtreeLeave(p);
+  return rc;
+#endif
+}
 
-  /*
-  ** Find the cell in the parent page whose left child points back
-  ** to pPage.  The "idx" variable is the index of that cell.  If pPage
-  ** is the rightmost child of pParent then set idx to pParent->nCell 
+
+/*
+** Get a reference to pPage1 of the database file.  This will
+** also acquire a readlock on that file.
+**
+** SQLITE_OK is returned on success.  If the file is not a
+** well-formed database file, then SQLITE_CORRUPT is returned.
+** SQLITE_BUSY is returned if the database is locked.  SQLITE_NOMEM
+** is returned if we run out of memory. 
+*/
+static int lockBtree(BtShared *pBt){
+  int rc;
+  MemPage *pPage1;
+  int nPage;
+
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( pBt->pPage1==0 );
+  rc = sqlite3PagerSharedLock(pBt->pPager);
+  if( rc!=SQLITE_OK ) return rc;
+  rc = btreeGetPage(pBt, 1, &pPage1, 0);
+  if( rc!=SQLITE_OK ) return rc;
+
+  /* Do some checking to help insure the file we opened really is
+  ** a valid database file. 
   */
-  if( pParent->idxShift ){
-    Pgno pgno;
-    pgno = pPage->pgno;
-    assert( pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
-    for(idx=0; idx<pParent->nCell; idx++){
-      if( get4byte(findCell(pParent, idx))==pgno ){
-        break;
-      }
+  rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
+  if( rc!=SQLITE_OK ){
+    goto page1_init_failed;
+  }else if( nPage>0 ){
+    int pageSize;
+    int usableSize;
+    u8 *page1 = pPage1->aData;
+    rc = SQLITE_NOTADB;
+    if( memcmp(page1, zMagicHeader, 16)!=0 ){
+      goto page1_init_failed;
     }
-    assert( idx<pParent->nCell
-             || get4byte(&pParent->aData[pParent->hdrOffset+8])==pgno );
-  }else{
-    idx = pPage->idxParent;
+    if( page1[18]>1 ){
+      pBt->readOnly = 1;
+    }
+    if( page1[19]>1 ){
+      goto page1_init_failed;
+    }
+
+    /* The maximum embedded fraction must be exactly 25%.  And the minimum
+    ** embedded fraction must be 12.5% for both leaf-data and non-leaf-data.
+    ** The original design allowed these amounts to vary, but as of
+    ** version 3.6.0, we require them to be fixed.
+    */
+    if( memcmp(&page1[21], "\100\040\040",3)!=0 ){
+      goto page1_init_failed;
+    }
+    pageSize = get2byte(&page1[16]);
+    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
+        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
+    ){
+      goto page1_init_failed;
+    }
+    assert( (pageSize & 7)==0 );
+    usableSize = pageSize - page1[20];
+    if( pageSize!=pBt->pageSize ){
+      /* After reading the first page of the database assuming a page size
+      ** of BtShared.pageSize, we have discovered that the page-size is
+      ** actually pageSize. Unlock the database, leave pBt->pPage1 at
+      ** zero and return SQLITE_OK. The caller will call this function
+      ** again with the correct page-size.
+      */
+      releasePage(pPage1);
+      pBt->usableSize = (u16)usableSize;
+      pBt->pageSize = (u16)pageSize;
+      freeTempSpace(pBt);
+      rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize,
+                                   pageSize-usableSize);
+      return rc;
+    }
+    if( usableSize<480 ){
+      goto page1_init_failed;
+    }
+    pBt->pageSize = (u16)pageSize;
+    pBt->usableSize = (u16)usableSize;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
+    pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
+#endif
   }
 
-  /*
-  ** Initialize variables so that it will be safe to jump
-  ** directly to balance_cleanup at any moment.
+  /* maxLocal is the maximum amount of payload to store locally for
+  ** a cell.  Make sure it is small enough so that at least minFanout
+  ** cells can will fit on one page.  We assume a 10-byte page header.
+  ** Besides the payload, the cell must store:
+  **     2-byte pointer to the cell
+  **     4-byte child pointer
+  **     9-byte nKey value
+  **     4-byte nData value
+  **     4-byte overflow page pointer
+  ** So a cell consists of a 2-byte poiner, a header which is as much as
+  ** 17 bytes long, 0 to N bytes of payload, and an optional 4 byte overflow
+  ** page pointer.
   */
-  nOld = nNew = 0;
-  sqlite3PagerRef(pParent->pDbPage);
+  pBt->maxLocal = (pBt->usableSize-12)*64/255 - 23;
+  pBt->minLocal = (pBt->usableSize-12)*32/255 - 23;
+  pBt->maxLeaf = pBt->usableSize - 35;
+  pBt->minLeaf = (pBt->usableSize-12)*32/255 - 23;
+  assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
+  pBt->pPage1 = pPage1;
+  return SQLITE_OK;
 
-  /*
-  ** Find sibling pages to pPage and the cells in pParent that divide
-  ** the siblings.  An attempt is made to find NN siblings on either
-  ** side of pPage.  More siblings are taken from one side, however, if
-  ** pPage there are fewer than NN siblings on the other side.  If pParent
-  ** has NB or fewer children then all children of pParent are taken.
-  */
-  nxDiv = idx - NN;
-  if( nxDiv + NB > pParent->nCell ){
-    nxDiv = pParent->nCell - NB + 1;
-  }
-  if( nxDiv<0 ){
-    nxDiv = 0;
-  }
-  nDiv = 0;
-  for(i=0, k=nxDiv; i<NB; i++, k++){
-    if( k<pParent->nCell ){
-      apDiv[i] = findCell(pParent, k);
-      nDiv++;
-      assert( !pParent->leaf );
-      pgnoOld[i] = get4byte(apDiv[i]);
-    }else if( k==pParent->nCell ){
-      pgnoOld[i] = get4byte(&pParent->aData[pParent->hdrOffset+8]);
-    }else{
-      break;
-    }
-    rc = getAndInitPage(pBt, pgnoOld[i], &apOld[i], pParent);
-    if( rc ) goto balance_cleanup;
-    apOld[i]->idxParent = k;
-    apCopy[i] = 0;
-    assert( i==nOld );
-    nOld++;
-    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
+page1_init_failed:
+  releasePage(pPage1);
+  pBt->pPage1 = 0;
+  return rc;
+}
+
+/*
+** If there are no outstanding cursors and we are not in the middle
+** of a transaction but there is a read lock on the database, then
+** this routine unrefs the first page of the database file which 
+** has the effect of releasing the read lock.
+**
+** If there is a transaction in progress, this routine is a no-op.
+*/
+static void unlockBtreeIfUnused(BtShared *pBt){
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( pBt->pCursor==0 || pBt->inTransaction>TRANS_NONE );
+  if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){
+    assert( pBt->pPage1->aData );
+    assert( sqlite3PagerRefcount(pBt->pPager)==1 );
+    assert( pBt->pPage1->aData );
+    releasePage(pBt->pPage1);
+    pBt->pPage1 = 0;
   }
+}
 
-  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte
-  ** alignment */
-  nMaxCells = (nMaxCells + 3)&~3;
+/*
+** If pBt points to an empty file then convert that empty file
+** into a new empty database by initializing the first page of
+** the database.
+*/
+static int newDatabase(BtShared *pBt){
+  MemPage *pP1;
+  unsigned char *data;
+  int rc;
+  int nPage;
 
-  /*
-  ** Allocate space for memory structures
-  */
-  apCell = sqlite3_malloc( 
-       nMaxCells*sizeof(u8*)                       /* apCell */
-     + nMaxCells*sizeof(u16)                       /* szCell */
-     + (ROUND8(sizeof(MemPage))+pBt->pageSize)*NB  /* aCopy */
-     + pBt->pageSize*5                             /* aSpace */
-     + (ISAUTOVACUUM ? nMaxCells : 0)              /* aFrom */
-  );
-  if( apCell==0 ){
-    rc = SQLITE_NOMEM;
-    goto balance_cleanup;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  /* The database size has already been measured and cached, so failure
+  ** is impossible here.  If the original size measurement failed, then
+  ** processing aborts before entering this routine. */
+  rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
+  if( NEVER(rc!=SQLITE_OK) || nPage>0 ){
+    return rc;
   }
-  szCell = (u16*)&apCell[nMaxCells];
-  aCopy[0] = (u8*)&szCell[nMaxCells];
-  assert( ((aCopy[0] - (u8*)apCell) & 7)==0 ); /* 8-byte alignment required */
-  for(i=1; i<NB; i++){
-    aCopy[i] = &aCopy[i-1][pBt->pageSize+ROUND8(sizeof(MemPage))];
-    assert( ((aCopy[i] - (u8*)apCell) & 7)==0 ); /* 8-byte alignment required */
-  }
-  aSpace = &aCopy[NB-1][pBt->pageSize+ROUND8(sizeof(MemPage))];
-  assert( ((aSpace - (u8*)apCell) & 7)==0 ); /* 8-byte alignment required */
+  pP1 = pBt->pPage1;
+  assert( pP1!=0 );
+  data = pP1->aData;
+  rc = sqlite3PagerWrite(pP1->pDbPage);
+  if( rc ) return rc;
+  memcpy(data, zMagicHeader, sizeof(zMagicHeader));
+  assert( sizeof(zMagicHeader)==16 );
+  put2byte(&data[16], pBt->pageSize);
+  data[18] = 1;
+  data[19] = 1;
+  assert( pBt->usableSize<=pBt->pageSize && pBt->usableSize+255>=pBt->pageSize);
+  data[20] = (u8)(pBt->pageSize - pBt->usableSize);
+  data[21] = 64;
+  data[22] = 32;
+  data[23] = 32;
+  memset(&data[24], 0, 100-24);
+  zeroPage(pP1, PTF_INTKEY|PTF_LEAF|PTF_LEAFDATA );
+  pBt->pageSizeFixed = 1;
 #ifndef SQLITE_OMIT_AUTOVACUUM
-  if( pBt->autoVacuum ){
-    aFrom = &aSpace[5*pBt->pageSize];
-  }
+  assert( pBt->autoVacuum==1 || pBt->autoVacuum==0 );
+  assert( pBt->incrVacuum==1 || pBt->incrVacuum==0 );
+  put4byte(&data[36 + 4*4], pBt->autoVacuum);
+  put4byte(&data[36 + 7*4], pBt->incrVacuum);
 #endif
-  
-  /*
-  ** Make copies of the content of pPage and its siblings into aOld[].
-  ** The rest of this function will use data from the copies rather
-  ** that the original pages since the original pages will be in the
-  ** process of being overwritten.
+  return SQLITE_OK;
+}
+
+/*
+** Attempt to start a new transaction. A write-transaction
+** is started if the second argument is nonzero, otherwise a read-
+** transaction.  If the second argument is 2 or more and exclusive
+** transaction is started, meaning that no other process is allowed
+** to access the database.  A preexisting transaction may not be
+** upgraded to exclusive by calling this routine a second time - the
+** exclusivity flag only works for a new transaction.
+**
+** A write-transaction must be started before attempting any 
+** changes to the database.  None of the following routines 
+** will work unless a transaction is started first:
+**
+**      sqlite3BtreeCreateTable()
+**      sqlite3BtreeCreateIndex()
+**      sqlite3BtreeClearTable()
+**      sqlite3BtreeDropTable()
+**      sqlite3BtreeInsert()
+**      sqlite3BtreeDelete()
+**      sqlite3BtreeUpdateMeta()
+**
+** If an initial attempt to acquire the lock fails because of lock contention
+** and the database was previously unlocked, then invoke the busy handler
+** if there is one.  But if there was previously a read-lock, do not
+** invoke the busy handler - just return SQLITE_BUSY.  SQLITE_BUSY is 
+** returned when there is already a read-lock in order to avoid a deadlock.
+**
+** Suppose there are two processes A and B.  A has a read lock and B has
+** a reserved lock.  B tries to promote to exclusive but is blocked because
+** of A's read lock.  A tries to promote to reserved but is blocked by B.
+** One or the other of the two processes must give way or there can be
+** no progress.  By returning SQLITE_BUSY and not invoking the busy callback
+** when A already has a read lock, we encourage A to give up and let B
+** proceed.
+*/
+SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
+  sqlite3 *pBlock = 0;
+  BtShared *pBt = p->pBt;
+  int rc = SQLITE_OK;
+
+  sqlite3BtreeEnter(p);
+  btreeIntegrity(p);
+
+  /* If the btree is already in a write-transaction, or it
+  ** is already in a read-transaction and a read-transaction
+  ** is requested, this is a no-op.
   */
-  for(i=0; i<nOld; i++){
-    MemPage *p = apCopy[i] = (MemPage*)aCopy[i];
-    memcpy(p, apOld[i], sizeof(MemPage));
-    p->aData = (void*)&p[1];
-    memcpy(p->aData, apOld[i]->aData, pBt->pageSize);
+  if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
+    goto trans_begun;
   }
 
-  /*
-  ** Load pointers to all cells on sibling pages and the divider cells
-  ** into the local apCell[] array.  Make copies of the divider cells
-  ** into space obtained form aSpace[] and remove the the divider Cells
-  ** from pParent.
-  **
-  ** If the siblings are on leaf pages, then the child pointers of the
-  ** divider cells are stripped from the cells before they are copied
-  ** into aSpace[].  In this way, all cells in apCell[] are without
-  ** child pointers.  If siblings are not leaves, then all cell in
-  ** apCell[] include child pointers.  Either way, all cells in apCell[]
-  ** are alike.
-  **
-  ** leafCorrection:  4 if pPage is a leaf.  0 if pPage is not a leaf.
-  **       leafData:  1 if pPage holds key+data and pParent holds only keys.
+  /* Write transactions are not possible on a read-only database */
+  if( pBt->readOnly && wrflag ){
+    rc = SQLITE_READONLY;
+    goto trans_begun;
+  }
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  /* If another database handle has already opened a write transaction 
+  ** on this shared-btree structure and a second write transaction is
+  ** requested, return SQLITE_LOCKED.
   */
-  nCell = 0;
-  leafCorrection = pPage->leaf*4;
-  leafData = pPage->leafData && pPage->leaf;
-  for(i=0; i<nOld; i++){
-    MemPage *pOld = apCopy[i];
-    int limit = pOld->nCell+pOld->nOverflow;
-    for(j=0; j<limit; j++){
-      assert( nCell<nMaxCells );
-      apCell[nCell] = findOverflowCell(pOld, j);
-      szCell[nCell] = cellSizePtr(pOld, apCell[nCell]);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( pBt->autoVacuum ){
-        int a;
-        aFrom[nCell] = i;
-        for(a=0; a<pOld->nOverflow; a++){
-          if( pOld->aOvfl[a].pCell==apCell[nCell] ){
-            aFrom[nCell] = 0xFF;
-            break;
-          }
-        }
+  if( (wrflag && pBt->inTransaction==TRANS_WRITE) || pBt->isPending ){
+    pBlock = pBt->pWriter->db;
+  }else if( wrflag>1 ){
+    BtLock *pIter;
+    for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
+      if( pIter->pBtree!=p ){
+        pBlock = pIter->pBtree->db;
+        break;
       }
-#endif
-      nCell++;
     }
-    if( i<nOld-1 ){
-      u16 sz = cellSizePtr(pParent, apDiv[i]);
-      if( leafData ){
-        /* With the LEAFDATA flag, pParent cells hold only INTKEYs that
-        ** are duplicates of keys on the child pages.  We need to remove
-        ** the divider cells from pParent, but the dividers cells are not
-        ** added to apCell[] because they are duplicates of child cells.
-        */
-        dropCell(pParent, nxDiv, sz);
-      }else{
-        u8 *pTemp;
-        assert( nCell<nMaxCells );
-        szCell[nCell] = sz;
-        pTemp = &aSpace[iSpace];
-        iSpace += sz;
-        assert( iSpace<=pBt->pageSize*5 );
-        memcpy(pTemp, apDiv[i], sz);
-        apCell[nCell] = pTemp+leafCorrection;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-        if( pBt->autoVacuum ){
-          aFrom[nCell] = 0xFF;
-        }
+  }
+  if( pBlock ){
+    sqlite3ConnectionBlocked(p->db, pBlock);
+    rc = SQLITE_LOCKED_SHAREDCACHE;
+    goto trans_begun;
+  }
 #endif
-        dropCell(pParent, nxDiv, sz);
-        szCell[nCell] -= leafCorrection;
-        assert( get4byte(pTemp)==pgnoOld[i] );
-        if( !pOld->leaf ){
-          assert( leafCorrection==0 );
-          /* The right pointer of the child page pOld becomes the left
-          ** pointer of the divider cell */
-          memcpy(apCell[nCell], &pOld->aData[pOld->hdrOffset+8], 4);
-        }else{
-          assert( leafCorrection==4 );
-          if( szCell[nCell]<4 ){
-            /* Do not allow any cells smaller than 4 bytes. */
-            szCell[nCell] = 4;
-          }
+
+  /* Any read-only or read-write transaction implies a read-lock on 
+  ** page 1. So if some other shared-cache client already has a write-lock 
+  ** on page 1, the transaction cannot be opened. */
+  rc = querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK);
+  if( SQLITE_OK!=rc ) goto trans_begun;
+
+  do {
+    /* Call lockBtree() until either pBt->pPage1 is populated or
+    ** lockBtree() returns something other than SQLITE_OK. lockBtree()
+    ** may return SQLITE_OK but leave pBt->pPage1 set to 0 if after
+    ** reading page 1 it discovers that the page-size of the database 
+    ** file is not pBt->pageSize. In this case lockBtree() will update
+    ** pBt->pageSize to the page-size of the file on disk.
+    */
+    while( pBt->pPage1==0 && SQLITE_OK==(rc = lockBtree(pBt)) );
+
+    if( rc==SQLITE_OK && wrflag ){
+      if( pBt->readOnly ){
+        rc = SQLITE_READONLY;
+      }else{
+        rc = sqlite3PagerBegin(pBt->pPager,wrflag>1,sqlite3TempInMemory(p->db));
+        if( rc==SQLITE_OK ){
+          rc = newDatabase(pBt);
         }
-        nCell++;
       }
     }
-  }
-
-  /*
-  ** Figure out the number of pages needed to hold all nCell cells.
-  ** Store this number in "k".  Also compute szNew[] which is the total
-  ** size of all cells on the i-th page and cntNew[] which is the index
-  ** in apCell[] of the cell that divides page i from page i+1.  
-  ** cntNew[k] should equal nCell.
-  **
-  ** Values computed by this block:
-  **
-  **           k: The total number of sibling pages
-  **    szNew[i]: Spaced used on the i-th sibling page.
-  **   cntNew[i]: Index in apCell[] and szCell[] for the first cell to
-  **              the right of the i-th sibling page.
-  ** usableSpace: Number of bytes of space available on each sibling.
-  ** 
-  */
-  usableSpace = pBt->usableSize - 12 + leafCorrection;
-  for(subtotal=k=i=0; i<nCell; i++){
-    assert( i<nMaxCells );
-    subtotal += szCell[i] + 2;
-    if( subtotal > usableSpace ){
-      szNew[k] = subtotal - szCell[i];
-      cntNew[k] = i;
-      if( leafData ){ i--; }
-      subtotal = 0;
-      k++;
+  
+    if( rc!=SQLITE_OK ){
+      unlockBtreeIfUnused(pBt);
     }
-  }
-  szNew[k] = subtotal;
-  cntNew[k] = nCell;
-  k++;
-
-  /*
-  ** The packing computed by the previous block is biased toward the siblings
-  ** on the left side.  The left siblings are always nearly full, while the
-  ** right-most sibling might be nearly empty.  This block of code attempts
-  ** to adjust the packing of siblings to get a better balance.
-  **
-  ** This adjustment is more than an optimization.  The packing above might
-  ** be so out of balance as to be illegal.  For example, the right-most
-  ** sibling might be completely empty.  This adjustment is not optional.
-  */
-  for(i=k-1; i>0; i--){
-    int szRight = szNew[i];  /* Size of sibling on the right */
-    int szLeft = szNew[i-1]; /* Size of sibling on the left */
-    int r;              /* Index of right-most cell in left sibling */
-    int d;              /* Index of first cell to the left of right sibling */
+  }while( rc==SQLITE_BUSY && pBt->inTransaction==TRANS_NONE &&
+          btreeInvokeBusyHandler(pBt) );
 
-    r = cntNew[i-1] - 1;
-    d = r + 1 - leafData;
-    assert( d<nMaxCells );
-    assert( r<nMaxCells );
-    while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){
-      szRight += szCell[d] + 2;
-      szLeft -= szCell[r] + 2;
-      cntNew[i-1]--;
-      r = cntNew[i-1] - 1;
-      d = r + 1 - leafData;
+  if( rc==SQLITE_OK ){
+    if( p->inTrans==TRANS_NONE ){
+      pBt->nTransaction++;
+#ifndef SQLITE_OMIT_SHARED_CACHE
+      if( p->sharable ){
+	assert( p->lock.pBtree==p && p->lock.iTable==1 );
+        p->lock.eLock = READ_LOCK;
+        p->lock.pNext = pBt->pLock;
+        pBt->pLock = &p->lock;
+      }
+#endif
     }
-    szNew[i] = szRight;
-    szNew[i-1] = szLeft;
+    p->inTrans = (wrflag?TRANS_WRITE:TRANS_READ);
+    if( p->inTrans>pBt->inTransaction ){
+      pBt->inTransaction = p->inTrans;
+    }
+#ifndef SQLITE_OMIT_SHARED_CACHE
+    if( wrflag ){
+      assert( !pBt->pWriter );
+      pBt->pWriter = p;
+      pBt->isExclusive = (u8)(wrflag>1);
+    }
+#endif
   }
 
-  /* Either we found one or more cells (cntnew[0])>0) or we are the
-  ** a virtual root page.  A virtual root page is when the real root
-  ** page is page 1 and we are the only child of that page.
-  */
-  assert( cntNew[0]>0 || (pParent->pgno==1 && pParent->nCell==0) );
 
-  /*
-  ** Allocate k new pages.  Reuse old pages where possible.
-  */
-  assert( pPage->pgno>1 );
-  pageFlags = pPage->aData[0];
-  for(i=0; i<k; i++){
-    MemPage *pNew;
-    if( i<nOld ){
-      pNew = apNew[i] = apOld[i];
-      pgnoNew[i] = pgnoOld[i];
-      apOld[i] = 0;
-      rc = sqlite3PagerWrite(pNew->pDbPage);
-      nNew++;
-      if( rc ) goto balance_cleanup;
-    }else{
-      assert( i>0 );
-      rc = allocateBtreePage(pBt, &pNew, &pgnoNew[i], pgnoNew[i-1], 0);
-      if( rc ) goto balance_cleanup;
-      apNew[i] = pNew;
-      nNew++;
-    }
-    zeroPage(pNew, pageFlags);
+trans_begun:
+  if( rc==SQLITE_OK && wrflag ){
+    /* This call makes sure that the pager has the correct number of
+    ** open savepoints. If the second parameter is greater than 0 and
+    ** the sub-journal is not already open, then it will be opened here.
+    */
+    rc = sqlite3PagerOpenSavepoint(pBt->pPager, p->db->nSavepoint);
   }
 
-  /* Free any old pages that were not reused as new pages.
-  */
-  while( i<nOld ){
-    rc = freePage(apOld[i]);
-    if( rc ) goto balance_cleanup;
-    releasePage(apOld[i]);
-    apOld[i] = 0;
-    i++;
-  }
+  btreeIntegrity(p);
+  sqlite3BtreeLeave(p);
+  return rc;
+}
 
-  /*
-  ** Put the new pages in accending order.  This helps to
-  ** keep entries in the disk file in order so that a scan
-  ** of the table is a linear scan through the file.  That
-  ** in turn helps the operating system to deliver pages
-  ** from the disk more rapidly.
-  **
-  ** An O(n^2) insertion sort algorithm is used, but since
-  ** n is never more than NB (a small constant), that should
-  ** not be a problem.
-  **
-  ** When NB==3, this one optimization makes the database
-  ** about 25% faster for large insertions and deletions.
-  */
-  for(i=0; i<k-1; i++){
-    int minV = pgnoNew[i];
-    int minI = i;
-    for(j=i+1; j<k; j++){
-      if( pgnoNew[j]<(unsigned)minV ){
-        minI = j;
-        minV = pgnoNew[j];
-      }
-    }
-    if( minI>i ){
-      int t;
-      MemPage *pT;
-      t = pgnoNew[i];
-      pT = apNew[i];
-      pgnoNew[i] = pgnoNew[minI];
-      apNew[i] = apNew[minI];
-      pgnoNew[minI] = t;
-      apNew[minI] = pT;
-    }
+#ifndef SQLITE_OMIT_AUTOVACUUM
+
+/*
+** Set the pointer-map entries for all children of page pPage. Also, if
+** pPage contains cells that point to overflow pages, set the pointer
+** map entries for the overflow pages as well.
+*/
+static int setChildPtrmaps(MemPage *pPage){
+  int i;                             /* Counter variable */
+  int nCell;                         /* Number of cells in page pPage */
+  int rc;                            /* Return code */
+  BtShared *pBt = pPage->pBt;
+  u8 isInitOrig = pPage->isInit;
+  Pgno pgno = pPage->pgno;
+
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  rc = btreeInitPage(pPage);
+  if( rc!=SQLITE_OK ){
+    goto set_child_ptrmaps_out;
   }
-  TRACE(("BALANCE: old: %d %d %d  new: %d(%d) %d(%d) %d(%d) %d(%d) %d(%d)\n",
-    pgnoOld[0], 
-    nOld>=2 ? pgnoOld[1] : 0,
-    nOld>=3 ? pgnoOld[2] : 0,
-    pgnoNew[0], szNew[0],
-    nNew>=2 ? pgnoNew[1] : 0, nNew>=2 ? szNew[1] : 0,
-    nNew>=3 ? pgnoNew[2] : 0, nNew>=3 ? szNew[2] : 0,
-    nNew>=4 ? pgnoNew[3] : 0, nNew>=4 ? szNew[3] : 0,
-    nNew>=5 ? pgnoNew[4] : 0, nNew>=5 ? szNew[4] : 0));
+  nCell = pPage->nCell;
 
-  /*
-  ** Evenly distribute the data in apCell[] across the new pages.
-  ** Insert divider cells into pParent as necessary.
-  */
-  j = 0;
-  for(i=0; i<nNew; i++){
-    /* Assemble the new sibling page. */
-    MemPage *pNew = apNew[i];
-    assert( j<nMaxCells );
-    assert( pNew->pgno==pgnoNew[i] );
-    assemblePage(pNew, cntNew[i]-j, &apCell[j], &szCell[j]);
-    assert( pNew->nCell>0 || (nNew==1 && cntNew[0]==0) );
-    assert( pNew->nOverflow==0 );
+  for(i=0; i<nCell; i++){
+    u8 *pCell = findCell(pPage, i);
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    /* If this is an auto-vacuum database, update the pointer map entries
-    ** that point to the siblings that were rearranged. These can be: left
-    ** children of cells, the right-child of the page, or overflow pages
-    ** pointed to by cells.
-    */
-    if( pBt->autoVacuum ){
-      for(k=j; k<cntNew[i]; k++){
-        assert( k<nMaxCells );
-        if( aFrom[k]==0xFF || apCopy[aFrom[k]]->pgno!=pNew->pgno ){
-          rc = ptrmapPutOvfl(pNew, k-j);
-          if( rc!=SQLITE_OK ){
-            goto balance_cleanup;
-          }
-        }
-      }
+    ptrmapPutOvflPtr(pPage, pCell, &rc);
+
+    if( !pPage->leaf ){
+      Pgno childPgno = get4byte(pCell);
+      ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno, &rc);
     }
-#endif
+  }
 
-    j = cntNew[i];
+  if( !pPage->leaf ){
+    Pgno childPgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+    ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno, &rc);
+  }
 
-    /* If the sibling page assembled above was not the right-most sibling,
-    ** insert a divider cell into the parent page.
-    */
-    if( i<nNew-1 && j<nCell ){
-      u8 *pCell;
-      u8 *pTemp;
-      int sz;
+set_child_ptrmaps_out:
+  pPage->isInit = isInitOrig;
+  return rc;
+}
 
-      assert( j<nMaxCells );
-      pCell = apCell[j];
-      sz = szCell[j] + leafCorrection;
-      if( !pNew->leaf ){
-        memcpy(&pNew->aData[8], pCell, 4);
-        pTemp = 0;
-      }else if( leafData ){
-        /* If the tree is a leaf-data tree, and the siblings are leaves, 
-        ** then there is no divider cell in apCell[]. Instead, the divider 
-        ** cell consists of the integer key for the right-most cell of 
-        ** the sibling-page assembled above only.
-        */
+/*
+** Somewhere on pPage is a pointer to page iFrom.  Modify this pointer so
+** that it points to iTo. Parameter eType describes the type of pointer to
+** be modified, as  follows:
+**
+** PTRMAP_BTREE:     pPage is a btree-page. The pointer points at a child 
+**                   page of pPage.
+**
+** PTRMAP_OVERFLOW1: pPage is a btree-page. The pointer points at an overflow
+**                   page pointed to by one of the cells on pPage.
+**
+** PTRMAP_OVERFLOW2: pPage is an overflow-page. The pointer points at the next
+**                   overflow page in the list.
+*/
+static int modifyPagePointer(MemPage *pPage, Pgno iFrom, Pgno iTo, u8 eType){
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  if( eType==PTRMAP_OVERFLOW2 ){
+    /* The pointer is always the first 4 bytes of the page in this case.  */
+    if( get4byte(pPage->aData)!=iFrom ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+    put4byte(pPage->aData, iTo);
+  }else{
+    u8 isInitOrig = pPage->isInit;
+    int i;
+    int nCell;
+
+    btreeInitPage(pPage);
+    nCell = pPage->nCell;
+
+    for(i=0; i<nCell; i++){
+      u8 *pCell = findCell(pPage, i);
+      if( eType==PTRMAP_OVERFLOW1 ){
         CellInfo info;
-        j--;
-        sqlite3BtreeParseCellPtr(pNew, apCell[j], &info);
-        pCell = &aSpace[iSpace];
-        fillInCell(pParent, pCell, 0, info.nKey, 0, 0, 0, &sz);
-        iSpace += sz;
-        assert( iSpace<=pBt->pageSize*5 );
-        pTemp = 0;
+        btreeParseCellPtr(pPage, pCell, &info);
+        if( info.iOverflow ){
+          if( iFrom==get4byte(&pCell[info.iOverflow]) ){
+            put4byte(&pCell[info.iOverflow], iTo);
+            break;
+          }
+        }
       }else{
-        pCell -= 4;
-        pTemp = &aSpace[iSpace];
-        iSpace += sz;
-        assert( iSpace<=pBt->pageSize*5 );
-        /* Obscure case for non-leaf-data trees: If the cell at pCell was
-        ** previously stored on a leaf node, and its reported size was 4
-        ** bytes, then it may actually be smaller than this 
-        ** (see sqlite3BtreeParseCellPtr(), 4 bytes is the minimum size of
-        ** any cell). But it is important to pass the correct size to 
-        ** insertCell(), so reparse the cell now.
-        **
-        ** Note that this can never happen in an SQLite data file, as all
-        ** cells are at least 4 bytes. It only happens in b-trees used
-        ** to evaluate "IN (SELECT ...)" and similar clauses.
-        */
-        if( szCell[j]==4 ){
-          assert(leafCorrection==4);
-          sz = cellSizePtr(pParent, pCell);
+        if( get4byte(pCell)==iFrom ){
+          put4byte(pCell, iTo);
+          break;
         }
       }
-      rc = insertCell(pParent, nxDiv, pCell, sz, pTemp, 4);
-      if( rc!=SQLITE_OK ) goto balance_cleanup;
-      put4byte(findOverflowCell(pParent,nxDiv), pNew->pgno);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      /* If this is an auto-vacuum database, and not a leaf-data tree,
-      ** then update the pointer map with an entry for the overflow page
-      ** that the cell just inserted points to (if any).
-      */
-      if( pBt->autoVacuum && !leafData ){
-        rc = ptrmapPutOvfl(pParent, nxDiv);
-        if( rc!=SQLITE_OK ){
-          goto balance_cleanup;
-        }
+    }
+  
+    if( i==nCell ){
+      if( eType!=PTRMAP_BTREE || 
+          get4byte(&pPage->aData[pPage->hdrOffset+8])!=iFrom ){
+        return SQLITE_CORRUPT_BKPT;
       }
-#endif
-      j++;
-      nxDiv++;
+      put4byte(&pPage->aData[pPage->hdrOffset+8], iTo);
     }
+
+    pPage->isInit = isInitOrig;
   }
-  assert( j==nCell );
-  assert( nOld>0 );
-  assert( nNew>0 );
-  if( (pageFlags & PTF_LEAF)==0 ){
-    memcpy(&apNew[nNew-1]->aData[8], &apCopy[nOld-1]->aData[8], 4);
-  }
-  if( nxDiv==pParent->nCell+pParent->nOverflow ){
-    /* Right-most sibling is the right-most child of pParent */
-    put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew[nNew-1]);
-  }else{
-    /* Right-most sibling is the left child of the first entry in pParent
-    ** past the right-most divider entry */
-    put4byte(findOverflowCell(pParent, nxDiv), pgnoNew[nNew-1]);
+  return SQLITE_OK;
+}
+
+
+/*
+** Move the open database page pDbPage to location iFreePage in the 
+** database. The pDbPage reference remains valid.
+**
+** The isCommit flag indicates that there is no need to remember that
+** the journal needs to be sync()ed before database page pDbPage->pgno 
+** can be written to. The caller has already promised not to write to that
+** page.
+*/
+static int relocatePage(
+  BtShared *pBt,           /* Btree */
+  MemPage *pDbPage,        /* Open page to move */
+  u8 eType,                /* Pointer map 'type' entry for pDbPage */
+  Pgno iPtrPage,           /* Pointer map 'page-no' entry for pDbPage */
+  Pgno iFreePage,          /* The location to move pDbPage to */
+  int isCommit             /* isCommit flag passed to sqlite3PagerMovepage */
+){
+  MemPage *pPtrPage;   /* The page that contains a pointer to pDbPage */
+  Pgno iDbPage = pDbPage->pgno;
+  Pager *pPager = pBt->pPager;
+  int rc;
+
+  assert( eType==PTRMAP_OVERFLOW2 || eType==PTRMAP_OVERFLOW1 || 
+      eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE );
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( pDbPage->pBt==pBt );
+
+  /* Move page iDbPage from its current location to page number iFreePage */
+  TRACE(("AUTOVACUUM: Moving %d to free page %d (ptr page %d type %d)\n", 
+      iDbPage, iFreePage, iPtrPage, eType));
+  rc = sqlite3PagerMovepage(pPager, pDbPage->pDbPage, iFreePage, isCommit);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
+  pDbPage->pgno = iFreePage;
 
-  /*
-  ** Reparent children of all cells.
+  /* If pDbPage was a btree-page, then it may have child pages and/or cells
+  ** that point to overflow pages. The pointer map entries for all these
+  ** pages need to be changed.
+  **
+  ** If pDbPage is an overflow page, then the first 4 bytes may store a
+  ** pointer to a subsequent overflow page. If this is the case, then
+  ** the pointer map needs to be updated for the subsequent overflow page.
   */
-  for(i=0; i<nNew; i++){
-    rc = reparentChildPages(apNew[i]);
-    if( rc!=SQLITE_OK ) goto balance_cleanup;
+  if( eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE ){
+    rc = setChildPtrmaps(pDbPage);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+  }else{
+    Pgno nextOvfl = get4byte(pDbPage->aData);
+    if( nextOvfl!=0 ){
+      ptrmapPut(pBt, nextOvfl, PTRMAP_OVERFLOW2, iFreePage, &rc);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+    }
   }
-  rc = reparentChildPages(pParent);
-  if( rc!=SQLITE_OK ) goto balance_cleanup;
 
-  /*
-  ** Balance the parent page.  Note that the current page (pPage) might
-  ** have been added to the freelist so it might no longer be initialized.
-  ** But the parent page will always be initialized.
-  */
-  assert( pParent->isInit );
-  rc = balance(pParent, 0);
-  
-  /*
-  ** Cleanup before returning.
+  /* Fix the database pointer on page iPtrPage that pointed at iDbPage so
+  ** that it points at iFreePage. Also fix the pointer map entry for
+  ** iPtrPage.
   */
-balance_cleanup:
-  sqlite3_free(apCell);
-  for(i=0; i<nOld; i++){
-    releasePage(apOld[i]);
-  }
-  for(i=0; i<nNew; i++){
-    releasePage(apNew[i]);
+  if( eType!=PTRMAP_ROOTPAGE ){
+    rc = btreeGetPage(pBt, iPtrPage, &pPtrPage, 0);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    rc = sqlite3PagerWrite(pPtrPage->pDbPage);
+    if( rc!=SQLITE_OK ){
+      releasePage(pPtrPage);
+      return rc;
+    }
+    rc = modifyPagePointer(pPtrPage, iDbPage, iFreePage, eType);
+    releasePage(pPtrPage);
+    if( rc==SQLITE_OK ){
+      ptrmapPut(pBt, iFreePage, eType, iPtrPage, &rc);
+    }
   }
-  releasePage(pParent);
-  TRACE(("BALANCE: finished with %d: old=%d new=%d cells=%d\n",
-          pPage->pgno, nOld, nNew, nCell));
   return rc;
 }
 
+/* Forward declaration required by incrVacuumStep(). */
+static int allocateBtreePage(BtShared *, MemPage **, Pgno *, Pgno, u8);
+
 /*
-** This routine is called for the root page of a btree when the root
-** page contains no cells.  This is an opportunity to make the tree
-** shallower by one level.
+** Perform a single step of an incremental-vacuum. If successful,
+** return SQLITE_OK. If there is no work to do (and therefore no
+** point in calling this function again), return SQLITE_DONE.
+**
+** More specificly, this function attempts to re-organize the 
+** database so that the last page of the file currently in use
+** is no longer in use.
+**
+** If the nFin parameter is non-zero, this function assumes
+** that the caller will keep calling incrVacuumStep() until
+** it returns SQLITE_DONE or an error, and that nFin is the
+** number of pages the database file will contain after this 
+** process is complete.  If nFin is zero, it is assumed that
+** incrVacuumStep() will be called a finite amount of times
+** which may or may not empty the freelist.  A full autovacuum
+** has nFin>0.  A "PRAGMA incremental_vacuum" has nFin==0.
 */
-static int balance_shallower(MemPage *pPage){
-  MemPage *pChild;             /* The only child page of pPage */
-  Pgno pgnoChild;              /* Page number for pChild */
-  int rc = SQLITE_OK;          /* Return code from subprocedures */
-  BtShared *pBt;                  /* The main BTree structure */
-  int mxCellPerPage;           /* Maximum number of cells per page */
-  u8 **apCell;                 /* All cells from pages being balanced */
-  u16 *szCell;                 /* Local size of all cells */
+static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
+  Pgno nFreeList;           /* Number of pages still on the free-list */
 
-  assert( pPage->pParent==0 );
-  assert( pPage->nCell==0 );
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  pBt = pPage->pBt;
-  mxCellPerPage = MX_CELL(pBt);
-  apCell = sqlite3_malloc( mxCellPerPage*(sizeof(u8*)+sizeof(u16)) );
-  if( apCell==0 ) return SQLITE_NOMEM;
-  szCell = (u16*)&apCell[mxCellPerPage];
-  if( pPage->leaf ){
-    /* The table is completely empty */
-    TRACE(("BALANCE: empty table %d\n", pPage->pgno));
-  }else{
-    /* The root page is empty but has one child.  Transfer the
-    ** information from that one child into the root page if it 
-    ** will fit.  This reduces the depth of the tree by one.
-    **
-    ** If the root page is page 1, it has less space available than
-    ** its child (due to the 100 byte header that occurs at the beginning
-    ** of the database fle), so it might not be able to hold all of the 
-    ** information currently contained in the child.  If this is the 
-    ** case, then do not do the transfer.  Leave page 1 empty except
-    ** for the right-pointer to the child page.  The child page becomes
-    ** the virtual root of the tree.
-    */
-    pgnoChild = get4byte(&pPage->aData[pPage->hdrOffset+8]);
-    assert( pgnoChild>0 );
-    assert( pgnoChild<=sqlite3PagerPagecount(pPage->pBt->pPager) );
-    rc = sqlite3BtreeGetPage(pPage->pBt, pgnoChild, &pChild, 0);
-    if( rc ) goto end_shallow_balance;
-    if( pPage->pgno==1 ){
-      rc = sqlite3BtreeInitPage(pChild, pPage);
-      if( rc ) goto end_shallow_balance;
-      assert( pChild->nOverflow==0 );
-      if( pChild->nFree>=100 ){
-        /* The child information will fit on the root page, so do the
-        ** copy */
-        int i;
-        zeroPage(pPage, pChild->aData[0]);
-        for(i=0; i<pChild->nCell; i++){
-          apCell[i] = findCell(pChild,i);
-          szCell[i] = cellSizePtr(pChild, apCell[i]);
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( iLastPg>nFin );
+
+  if( !PTRMAP_ISPAGE(pBt, iLastPg) && iLastPg!=PENDING_BYTE_PAGE(pBt) ){
+    int rc;
+    u8 eType;
+    Pgno iPtrPage;
+
+    nFreeList = get4byte(&pBt->pPage1->aData[36]);
+    if( nFreeList==0 ){
+      return SQLITE_DONE;
+    }
+
+    rc = ptrmapGet(pBt, iLastPg, &eType, &iPtrPage);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    if( eType==PTRMAP_ROOTPAGE ){
+      return SQLITE_CORRUPT_BKPT;
+    }
+
+    if( eType==PTRMAP_FREEPAGE ){
+      if( nFin==0 ){
+        /* Remove the page from the files free-list. This is not required
+        ** if nFin is non-zero. In that case, the free-list will be
+        ** truncated to zero after this function returns, so it doesn't 
+        ** matter if it still contains some garbage entries.
+        */
+        Pgno iFreePg;
+        MemPage *pFreePg;
+        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, 1);
+        if( rc!=SQLITE_OK ){
+          return rc;
         }
-        assemblePage(pPage, pChild->nCell, apCell, szCell);
-        /* Copy the right-pointer of the child to the parent. */
-        put4byte(&pPage->aData[pPage->hdrOffset+8], 
-            get4byte(&pChild->aData[pChild->hdrOffset+8]));
-        freePage(pChild);
-        TRACE(("BALANCE: child %d transfer to page 1\n", pChild->pgno));
-      }else{
-        /* The child has more information that will fit on the root.
-        ** The tree is already balanced.  Do nothing. */
-        TRACE(("BALANCE: child %d will not fit on page 1\n", pChild->pgno));
+        assert( iFreePg==iLastPg );
+        releasePage(pFreePg);
+      }
+    } else {
+      Pgno iFreePg;             /* Index of free page to move pLastPg to */
+      MemPage *pLastPg;
+
+      rc = btreeGetPage(pBt, iLastPg, &pLastPg, 0);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+
+      /* If nFin is zero, this loop runs exactly once and page pLastPg
+      ** is swapped with the first free page pulled off the free list.
+      **
+      ** On the other hand, if nFin is greater than zero, then keep
+      ** looping until a free-page located within the first nFin pages
+      ** of the file is found.
+      */
+      do {
+        MemPage *pFreePg;
+        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, 0, 0);
+        if( rc!=SQLITE_OK ){
+          releasePage(pLastPg);
+          return rc;
+        }
+        releasePage(pFreePg);
+      }while( nFin!=0 && iFreePg>nFin );
+      assert( iFreePg<iLastPg );
+      
+      rc = sqlite3PagerWrite(pLastPg->pDbPage);
+      if( rc==SQLITE_OK ){
+        rc = relocatePage(pBt, pLastPg, eType, iPtrPage, iFreePg, nFin!=0);
+      }
+      releasePage(pLastPg);
+      if( rc!=SQLITE_OK ){
+        return rc;
       }
-    }else{
-      memcpy(pPage->aData, pChild->aData, pPage->pBt->usableSize);
-      pPage->isInit = 0;
-      pPage->pParent = 0;
-      rc = sqlite3BtreeInitPage(pPage, 0);
-      assert( rc==SQLITE_OK );
-      freePage(pChild);
-      TRACE(("BALANCE: transfer child %d into root %d\n",
-              pChild->pgno, pPage->pgno));
     }
-    rc = reparentChildPages(pPage);
-    assert( pPage->nOverflow==0 );
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pBt->autoVacuum ){
-      int i;
-      for(i=0; i<pPage->nCell; i++){ 
-        rc = ptrmapPutOvfl(pPage, i);
+  }
+
+  if( nFin==0 ){
+    iLastPg--;
+    while( iLastPg==PENDING_BYTE_PAGE(pBt)||PTRMAP_ISPAGE(pBt, iLastPg) ){
+      if( PTRMAP_ISPAGE(pBt, iLastPg) ){
+        MemPage *pPg;
+        int rc = btreeGetPage(pBt, iLastPg, &pPg, 0);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        rc = sqlite3PagerWrite(pPg->pDbPage);
+        releasePage(pPg);
         if( rc!=SQLITE_OK ){
-          goto end_shallow_balance;
+          return rc;
         }
       }
+      iLastPg--;
     }
-#endif
-    releasePage(pChild);
+    sqlite3PagerTruncateImage(pBt->pPager, iLastPg);
   }
-end_shallow_balance:
-  sqlite3_free(apCell);
-  return rc;
+  return SQLITE_OK;
 }
 
-
 /*
-** The root page is overfull
+** A write-transaction must be opened before calling this function.
+** It performs a single unit of work towards an incremental vacuum.
 **
-** When this happens, Create a new child page and copy the
-** contents of the root into the child.  Then make the root
-** page an empty page with rightChild pointing to the new
-** child.   Finally, call balance_internal() on the new child
-** to cause it to split.
+** If the incremental vacuum is finished after this function has run,
+** SQLITE_DONE is returned. If it is not finished, but no error occurred,
+** SQLITE_OK is returned. Otherwise an SQLite error code. 
 */
-static int balance_deeper(MemPage *pPage){
-  int rc;             /* Return value from subprocedures */
-  MemPage *pChild;    /* Pointer to a new child page */
-  Pgno pgnoChild;     /* Page number of the new child page */
-  BtShared *pBt;         /* The BTree */
-  int usableSize;     /* Total usable size of a page */
-  u8 *data;           /* Content of the parent page */
-  u8 *cdata;          /* Content of the child page */
-  int hdr;            /* Offset to page header in parent */
-  int brk;            /* Offset to content of first cell in parent */
+SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *p){
+  int rc;
+  BtShared *pBt = p->pBt;
 
-  assert( pPage->pParent==0 );
-  assert( pPage->nOverflow>0 );
-  pBt = pPage->pBt;
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  rc = allocateBtreePage(pBt, &pChild, &pgnoChild, pPage->pgno, 0);
-  if( rc ) return rc;
-  assert( sqlite3PagerIswriteable(pChild->pDbPage) );
-  usableSize = pBt->usableSize;
-  data = pPage->aData;
-  hdr = pPage->hdrOffset;
-  brk = get2byte(&data[hdr+5]);
-  cdata = pChild->aData;
-  memcpy(cdata, &data[hdr], pPage->cellOffset+2*pPage->nCell-hdr);
-  memcpy(&cdata[brk], &data[brk], usableSize-brk);
-  assert( pChild->isInit==0 );
-  rc = sqlite3BtreeInitPage(pChild, pPage);
-  if( rc ) goto balancedeeper_out;
-  memcpy(pChild->aOvfl, pPage->aOvfl, pPage->nOverflow*sizeof(pPage->aOvfl[0]));
-  pChild->nOverflow = pPage->nOverflow;
-  if( pChild->nOverflow ){
-    pChild->nFree = 0;
-  }
-  assert( pChild->nCell==pPage->nCell );
-  zeroPage(pPage, pChild->aData[0] & ~PTF_LEAF);
-  put4byte(&pPage->aData[pPage->hdrOffset+8], pgnoChild);
-  TRACE(("BALANCE: copy root %d into %d\n", pPage->pgno, pChild->pgno));
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  if( pBt->autoVacuum ){
-    int i;
-    rc = ptrmapPut(pBt, pChild->pgno, PTRMAP_BTREE, pPage->pgno);
-    if( rc ) goto balancedeeper_out;
-    for(i=0; i<pChild->nCell; i++){
-      rc = ptrmapPutOvfl(pChild, i);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-    }
+  sqlite3BtreeEnter(p);
+  assert( pBt->inTransaction==TRANS_WRITE && p->inTrans==TRANS_WRITE );
+  if( !pBt->autoVacuum ){
+    rc = SQLITE_DONE;
+  }else{
+    invalidateAllOverflowCache(pBt);
+    rc = incrVacuumStep(pBt, 0, pagerPagecount(pBt));
   }
-#endif
-  rc = balance_nonroot(pChild);
-
-balancedeeper_out:
-  releasePage(pChild);
+  sqlite3BtreeLeave(p);
   return rc;
 }
 
 /*
-** Decide if the page pPage needs to be balanced.  If balancing is
-** required, call the appropriate balancing routine.
+** This routine is called prior to sqlite3PagerCommit when a transaction
+** is commited for an auto-vacuum database.
+**
+** If SQLITE_OK is returned, then *pnTrunc is set to the number of pages
+** the database file should be truncated to during the commit process. 
+** i.e. the database has been reorganized so that only the first *pnTrunc
+** pages are in use.
 */
-static int balance(MemPage *pPage, int insert){
+static int autoVacuumCommit(BtShared *pBt){
   int rc = SQLITE_OK;
-  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  if( pPage->pParent==0 ){
-    rc = sqlite3PagerWrite(pPage->pDbPage);
-    if( rc==SQLITE_OK && pPage->nOverflow>0 ){
-      rc = balance_deeper(pPage);
+  Pager *pPager = pBt->pPager;
+  VVA_ONLY( int nRef = sqlite3PagerRefcount(pPager) );
+
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  invalidateAllOverflowCache(pBt);
+  assert(pBt->autoVacuum);
+  if( !pBt->incrVacuum ){
+    Pgno nFin;         /* Number of pages in database after autovacuuming */
+    Pgno nFree;        /* Number of pages on the freelist initially */
+    Pgno nPtrmap;      /* Number of PtrMap pages to be freed */
+    Pgno iFree;        /* The next page to be freed */
+    int nEntry;        /* Number of entries on one ptrmap page */
+    Pgno nOrig;        /* Database size before freeing */
+
+    nOrig = pagerPagecount(pBt);
+    if( PTRMAP_ISPAGE(pBt, nOrig) || nOrig==PENDING_BYTE_PAGE(pBt) ){
+      /* It is not possible to create a database for which the final page
+      ** is either a pointer-map page or the pending-byte page. If one
+      ** is encountered, this indicates corruption.
+      */
+      return SQLITE_CORRUPT_BKPT;
     }
-    if( rc==SQLITE_OK && pPage->nCell==0 ){
-      rc = balance_shallower(pPage);
+
+    nFree = get4byte(&pBt->pPage1->aData[36]);
+    nEntry = pBt->usableSize/5;
+    nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+nEntry)/nEntry;
+    nFin = nOrig - nFree - nPtrmap;
+    if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<PENDING_BYTE_PAGE(pBt) ){
+      nFin--;
     }
-  }else{
-    if( pPage->nOverflow>0 || 
-        (!insert && pPage->nFree>pPage->pBt->usableSize*2/3) ){
-      rc = balance_nonroot(pPage);
+    while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
+      nFin--;
+    }
+    if( nFin>nOrig ) return SQLITE_CORRUPT_BKPT;
+
+    for(iFree=nOrig; iFree>nFin && rc==SQLITE_OK; iFree--){
+      rc = incrVacuumStep(pBt, nFin, iFree);
+    }
+    if( (rc==SQLITE_DONE || rc==SQLITE_OK) && nFree>0 ){
+      rc = SQLITE_OK;
+      rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
+      put4byte(&pBt->pPage1->aData[32], 0);
+      put4byte(&pBt->pPage1->aData[36], 0);
+      sqlite3PagerTruncateImage(pBt->pPager, nFin);
+    }
+    if( rc!=SQLITE_OK ){
+      sqlite3PagerRollback(pPager);
     }
   }
+
+  assert( nRef==sqlite3PagerRefcount(pPager) );
   return rc;
 }
 
+#else /* ifndef SQLITE_OMIT_AUTOVACUUM */
+# define setChildPtrmaps(x) SQLITE_OK
+#endif
+
 /*
-** This routine checks all cursors that point to table pgnoRoot.
-** If any of those cursors were opened with wrFlag==0 in a different
-** database connection (a database connection that shares the pager
-** cache with the current connection) and that other connection 
-** is not in the ReadUncommmitted state, then this routine returns 
-** SQLITE_LOCKED.
+** This routine does the first phase of a two-phase commit.  This routine
+** causes a rollback journal to be created (if it does not already exist)
+** and populated with enough information so that if a power loss occurs
+** the database can be restored to its original state by playing back
+** the journal.  Then the contents of the journal are flushed out to
+** the disk.  After the journal is safely on oxide, the changes to the
+** database are written into the database file and flushed to oxide.
+** At the end of this call, the rollback journal still exists on the
+** disk and we are still holding all locks, so the transaction has not
+** committed.  See sqlite3BtreeCommitPhaseTwo() for the second phase of the
+** commit process.
+**
+** This call is a no-op if no write-transaction is currently active on pBt.
 **
-** In addition to checking for read-locks (where a read-lock 
-** means a cursor opened with wrFlag==0) this routine also moves
-** all write cursors so that they are pointing to the 
-** first Cell on the root page.  This is necessary because an insert 
-** or delete might change the number of cells on a page or delete
-** a page entirely and we do not want to leave any cursors 
-** pointing to non-existant pages or cells.
+** Otherwise, sync the database file for the btree pBt. zMaster points to
+** the name of a master journal file that should be written into the
+** individual journal file, or is NULL, indicating no master journal file 
+** (single database transaction).
+**
+** When this is called, the master journal should already have been
+** created, populated with this journal pointer and synced to disk.
+**
+** Once this is routine has returned, the only thing required to commit
+** the write-transaction for this database file is to delete the journal.
 */
-static int checkReadLocks(Btree *pBtree, Pgno pgnoRoot, BtCursor *pExclude){
-  BtCursor *p;
-  BtShared *pBt = pBtree->pBt;
-  sqlite3 *db = pBtree->db;
-  assert( sqlite3BtreeHoldsMutex(pBtree) );
-  for(p=pBt->pCursor; p; p=p->pNext){
-    if( p==pExclude ) continue;
-    if( p->eState!=CURSOR_VALID ) continue;
-    if( p->pgnoRoot!=pgnoRoot ) continue;
-    if( p->wrFlag==0 ){
-      sqlite3 *dbOther = p->pBtree->db;
-      if( dbOther==0 ||
-         (dbOther!=db && (dbOther->flags & SQLITE_ReadUncommitted)==0) ){
-        return SQLITE_LOCKED;
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
+  int rc = SQLITE_OK;
+  if( p->inTrans==TRANS_WRITE ){
+    BtShared *pBt = p->pBt;
+    sqlite3BtreeEnter(p);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pBt->autoVacuum ){
+      rc = autoVacuumCommit(pBt);
+      if( rc!=SQLITE_OK ){
+        sqlite3BtreeLeave(p);
+        return rc;
       }
-    }else if( p->pPage->pgno!=p->pgnoRoot ){
-      moveToRoot(p);
     }
+#endif
+    rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, 0);
+    sqlite3BtreeLeave(p);
   }
-  return SQLITE_OK;
+  return rc;
 }
 
 /*
-** Make sure pBt->pTmpSpace points to an allocation of 
-** MX_CELL_SIZE(pBt) bytes.
+** This function is called from both BtreeCommitPhaseTwo() and BtreeRollback()
+** at the conclusion of a transaction.
 */
-static void allocateTempSpace(BtShared *pBt){
-  if( !pBt->pTmpSpace ){
-    pBt->pTmpSpace = sqlite3_malloc(MX_CELL_SIZE(pBt));
+static void btreeEndTransaction(Btree *p){
+  BtShared *pBt = p->pBt;
+  BtCursor *pCsr;
+  assert( sqlite3BtreeHoldsMutex(p) );
+
+  /* Search for a cursor held open by this b-tree connection. If one exists,
+  ** then the transaction will be downgraded to a read-only transaction
+  ** instead of actually concluded. A subsequent call to CommitPhaseTwo() 
+  ** or Rollback() will finish the transaction and unlock the database.  */
+  for(pCsr=pBt->pCursor; pCsr && pCsr->pBtree!=p; pCsr=pCsr->pNext);
+  assert( pCsr==0 || p->inTrans>TRANS_NONE );
+
+  btreeClearHasContent(pBt);
+  if( pCsr ){
+    downgradeAllSharedCacheTableLocks(p);
+    p->inTrans = TRANS_READ;
+  }else{
+    /* If the handle had any kind of transaction open, decrement the 
+    ** transaction count of the shared btree. If the transaction count 
+    ** reaches 0, set the shared state to TRANS_NONE. The unlockBtreeIfUnused()
+    ** call below will unlock the pager.  */
+    if( p->inTrans!=TRANS_NONE ){
+      clearAllSharedCacheTableLocks(p);
+      pBt->nTransaction--;
+      if( 0==pBt->nTransaction ){
+        pBt->inTransaction = TRANS_NONE;
+      }
+    }
+
+    /* Set the current transaction state to TRANS_NONE and unlock the 
+    ** pager if this call closed the only read or write transaction.  */
+    p->inTrans = TRANS_NONE;
+    unlockBtreeIfUnused(pBt);
   }
+
+  btreeIntegrity(p);
 }
 
 /*
-** Insert a new record into the BTree.  The key is given by (pKey,nKey)
-** and the data is given by (pData,nData).  The cursor is used only to
-** define what table the record should be inserted into.  The cursor
-** is left pointing at a random location.
+** Commit the transaction currently in progress.
 **
-** For an INTKEY table, only the nKey value of the key is used.  pKey is
-** ignored.  For a ZERODATA table, the pData and nData are both ignored.
+** This routine implements the second phase of a 2-phase commit.  The
+** sqlite3BtreeCommitPhaseOne() routine does the first phase and should
+** be invoked prior to calling this routine.  The sqlite3BtreeCommitPhaseOne()
+** routine did all the work of writing information out to disk and flushing the
+** contents so that they are written onto the disk platter.  All this
+** routine has to do is delete or truncate or zero the header in the
+** the rollback journal (which causes the transaction to commit) and
+** drop locks.
+**
+** This will release the write lock on the database file.  If there
+** are no active cursors, it also releases the read lock.
 */
-SQLITE_PRIVATE int sqlite3BtreeInsert(
-  BtCursor *pCur,                /* Insert data into the table of this cursor */
-  const void *pKey, i64 nKey,    /* The key of the new record */
-  const void *pData, int nData,  /* The data of the new record */
-  int nZero,                     /* Number of extra 0 bytes to append to data */
-  int appendBias                 /* True if this is likely an append */
-){
-  int rc;
-  int loc;
-  int szNew;
-  MemPage *pPage;
-  Btree *p = pCur->pBtree;
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree *p){
   BtShared *pBt = p->pBt;
-  unsigned char *oldCell;
-  unsigned char *newCell = 0;
 
-  assert( cursorHoldsMutex(pCur) );
-  if( pBt->inTransaction!=TRANS_WRITE ){
-    /* Must start a transaction before doing an insert */
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-    return rc;
-  }
-  assert( !pBt->readOnly );
-  if( !pCur->wrFlag ){
-    return SQLITE_PERM;   /* Cursor not open for writing */
-  }
-  if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur) ){
-    return SQLITE_LOCKED; /* The table pCur points to has a read lock */
-  }
-  if( pCur->eState==CURSOR_FAULT ){
-    return pCur->skip;
-  }
+  sqlite3BtreeEnter(p);
+  btreeIntegrity(p);
 
-  /* Save the positions of any other cursors open on this table */
-  clearCursorPosition(pCur);
-  if( 
-    SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) ||
-    SQLITE_OK!=(rc = sqlite3BtreeMoveto(pCur, pKey, 0, nKey, appendBias, &loc))
-  ){
-    return rc;
-  }
-
-  pPage = pCur->pPage;
-  assert( pPage->intKey || nKey>=0 );
-  assert( pPage->leaf || !pPage->leafData );
-  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
-          pCur->pgnoRoot, nKey, nData, pPage->pgno,
-          loc==0 ? "overwrite" : "new entry"));
-  assert( pPage->isInit );
-  allocateTempSpace(pBt);
-  newCell = pBt->pTmpSpace;
-  if( newCell==0 ) return SQLITE_NOMEM;
-  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
-  if( rc ) goto end_insert;
-  assert( szNew==cellSizePtr(pPage, newCell) );
-  assert( szNew<=MX_CELL_SIZE(pBt) );
-  if( loc==0 && CURSOR_VALID==pCur->eState ){
-    u16 szOld;
-    assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
-    rc = sqlite3PagerWrite(pPage->pDbPage);
-    if( rc ){
-      goto end_insert;
-    }
-    oldCell = findCell(pPage, pCur->idx);
-    if( !pPage->leaf ){
-      memcpy(newCell, oldCell, 4);
+  /* If the handle has a write-transaction open, commit the shared-btrees 
+  ** transaction and set the shared state to TRANS_READ.
+  */
+  if( p->inTrans==TRANS_WRITE ){
+    int rc;
+    assert( pBt->inTransaction==TRANS_WRITE );
+    assert( pBt->nTransaction>0 );
+    rc = sqlite3PagerCommitPhaseTwo(pBt->pPager);
+    if( rc!=SQLITE_OK ){
+      sqlite3BtreeLeave(p);
+      return rc;
     }
-    szOld = cellSizePtr(pPage, oldCell);
-    rc = clearCell(pPage, oldCell);
-    if( rc ) goto end_insert;
-    dropCell(pPage, pCur->idx, szOld);
-  }else if( loc<0 && pPage->nCell>0 ){
-    assert( pPage->leaf );
-    pCur->idx++;
-    pCur->info.nSize = 0;
-    pCur->validNKey = 0;
-  }else{
-    assert( pPage->leaf );
-  }
-  rc = insertCell(pPage, pCur->idx, newCell, szNew, 0, 0);
-  if( rc!=SQLITE_OK ) goto end_insert;
-  rc = balance(pPage, 1);
-  /* sqlite3BtreePageDump(pCur->pBt, pCur->pgnoRoot, 1); */
-  /* fflush(stdout); */
-  if( rc==SQLITE_OK ){
-    moveToRoot(pCur);
+    pBt->inTransaction = TRANS_READ;
   }
-end_insert:
-  return rc;
+
+  btreeEndTransaction(p);
+  sqlite3BtreeLeave(p);
+  return SQLITE_OK;
 }
 
 /*
-** Delete the entry that the cursor is pointing to.  The cursor
-** is left pointing at a random location.
+** Do both phases of a commit.
 */
-SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor *pCur){
-  MemPage *pPage = pCur->pPage;
-  unsigned char *pCell;
+SQLITE_PRIVATE int sqlite3BtreeCommit(Btree *p){
   int rc;
-  Pgno pgnoChild = 0;
-  Btree *p = pCur->pBtree;
-  BtShared *pBt = p->pBt;
-
-  assert( cursorHoldsMutex(pCur) );
-  assert( pPage->isInit );
-  if( pBt->inTransaction!=TRANS_WRITE ){
-    /* Must start a transaction before doing a delete */
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-    return rc;
-  }
-  assert( !pBt->readOnly );
-  if( pCur->eState==CURSOR_FAULT ){
-    return pCur->skip;
-  }
-  if( pCur->idx >= pPage->nCell ){
-    return SQLITE_ERROR;  /* The cursor is not pointing to anything */
-  }
-  if( !pCur->wrFlag ){
-    return SQLITE_PERM;   /* Did not open this cursor for writing */
-  }
-  if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur) ){
-    return SQLITE_LOCKED; /* The table pCur points to has a read lock */
-  }
-
-  /* Restore the current cursor position (a no-op if the cursor is not in 
-  ** CURSOR_REQUIRESEEK state) and save the positions of any other cursors 
-  ** open on the same table. Then call sqlite3PagerWrite() on the page
-  ** that the entry will be deleted from.
-  */
-  if( 
-    (rc = restoreOrClearCursorPosition(pCur))!=0 ||
-    (rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur))!=0 ||
-    (rc = sqlite3PagerWrite(pPage->pDbPage))!=0
-  ){
-    return rc;
+  sqlite3BtreeEnter(p);
+  rc = sqlite3BtreeCommitPhaseOne(p, 0);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3BtreeCommitPhaseTwo(p);
   }
+  sqlite3BtreeLeave(p);
+  return rc;
+}
 
-  /* Locate the cell within its page and leave pCell pointing to the
-  ** data. The clearCell() call frees any overflow pages associated with the
-  ** cell. The cell itself is still intact.
-  */
-  pCell = findCell(pPage, pCur->idx);
-  if( !pPage->leaf ){
-    pgnoChild = get4byte(pCell);
-  }
-  rc = clearCell(pPage, pCell);
-  if( rc ){
-    return rc;
+#ifndef NDEBUG
+/*
+** Return the number of write-cursors open on this handle. This is for use
+** in assert() expressions, so it is only compiled if NDEBUG is not
+** defined.
+**
+** For the purposes of this routine, a write-cursor is any cursor that
+** is capable of writing to the databse.  That means the cursor was
+** originally opened for writing and the cursor has not be disabled
+** by having its state changed to CURSOR_FAULT.
+*/
+static int countWriteCursors(BtShared *pBt){
+  BtCursor *pCur;
+  int r = 0;
+  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
+    if( pCur->wrFlag && pCur->eState!=CURSOR_FAULT ) r++; 
   }
+  return r;
+}
+#endif
 
-  if( !pPage->leaf ){
-    /*
-    ** The entry we are about to delete is not a leaf so if we do not
-    ** do something we will leave a hole on an internal page.
-    ** We have to fill the hole by moving in a cell from a leaf.  The
-    ** next Cell after the one to be deleted is guaranteed to exist and
-    ** to be a leaf so we can use it.
-    */
-    BtCursor leafCur;
-    unsigned char *pNext;
-    int notUsed;
-    unsigned char *tempCell = 0;
-    assert( !pPage->leafData );
-    sqlite3BtreeGetTempCursor(pCur, &leafCur);
-    rc = sqlite3BtreeNext(&leafCur, &notUsed);
-    if( rc==SQLITE_OK ){
-      rc = sqlite3PagerWrite(leafCur.pPage->pDbPage);
-    }
-    if( rc==SQLITE_OK ){
-      u16 szNext;
-      TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
-         pCur->pgnoRoot, pPage->pgno, leafCur.pPage->pgno));
-      dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
-      pNext = findCell(leafCur.pPage, leafCur.idx);
-      szNext = cellSizePtr(leafCur.pPage, pNext);
-      assert( MX_CELL_SIZE(pBt)>=szNext+4 );
-      allocateTempSpace(pBt);
-      tempCell = pBt->pTmpSpace;
-      if( tempCell==0 ){
-        rc = SQLITE_NOMEM;
-      }
-      if( rc==SQLITE_OK ){
-        rc = insertCell(pPage, pCur->idx, pNext-4, szNext+4, tempCell, 0);
-      }
-      if( rc==SQLITE_OK ){
-        put4byte(findOverflowCell(pPage, pCur->idx), pgnoChild);
-        rc = balance(pPage, 0);
-      }
-      if( rc==SQLITE_OK ){
-        dropCell(leafCur.pPage, leafCur.idx, szNext);
-        rc = balance(leafCur.pPage, 0);
-      }
+/*
+** This routine sets the state to CURSOR_FAULT and the error
+** code to errCode for every cursor on BtShared that pBtree
+** references.
+**
+** Every cursor is tripped, including cursors that belong
+** to other database connections that happen to be sharing
+** the cache with pBtree.
+**
+** This routine gets called when a rollback occurs.
+** All cursors using the same cache must be tripped
+** to prevent them from trying to use the btree after
+** the rollback.  The rollback may have deleted tables
+** or moved root pages, so it is not sufficient to
+** save the state of the cursor.  The cursor must be
+** invalidated.
+*/
+SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode){
+  BtCursor *p;
+  sqlite3BtreeEnter(pBtree);
+  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
+    int i;
+    sqlite3BtreeClearCursor(p);
+    p->eState = CURSOR_FAULT;
+    p->skipNext = errCode;
+    for(i=0; i<=p->iPage; i++){
+      releasePage(p->apPage[i]);
+      p->apPage[i] = 0;
     }
-    sqlite3BtreeReleaseTempCursor(&leafCur);
-  }else{
-    TRACE(("DELETE: table=%d delete from leaf %d\n",
-       pCur->pgnoRoot, pPage->pgno));
-    dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
-    rc = balance(pPage, 0);
-  }
-  if( rc==SQLITE_OK ){
-    moveToRoot(pCur);
   }
-  return rc;
+  sqlite3BtreeLeave(pBtree);
 }
 
 /*
-** Create a new BTree table.  Write into *piTable the page
-** number for the root page of the new table.
-**
-** The type of type is determined by the flags parameter.  Only the
-** following values of flags are currently in use.  Other values for
-** flags might not work:
+** Rollback the transaction in progress.  All cursors will be
+** invalided by this operation.  Any attempt to use a cursor
+** that was open at the beginning of this operation will result
+** in an error.
 **
-**     BTREE_INTKEY|BTREE_LEAFDATA     Used for SQL tables with rowid keys
-**     BTREE_ZERODATA                  Used for SQL indices
+** This will release the write lock on the database file.  If there
+** are no active cursors, it also releases the read lock.
 */
-static int btreeCreateTable(Btree *p, int *piTable, int flags){
-  BtShared *pBt = p->pBt;
-  MemPage *pRoot;
-  Pgno pgnoRoot;
+SQLITE_PRIVATE int sqlite3BtreeRollback(Btree *p){
   int rc;
+  BtShared *pBt = p->pBt;
+  MemPage *pPage1;
 
-  assert( sqlite3BtreeHoldsMutex(p) );
-  if( pBt->inTransaction!=TRANS_WRITE ){
-    /* Must start a transaction first */
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-    return rc;
-  }
-  assert( !pBt->readOnly );
-
-#ifdef SQLITE_OMIT_AUTOVACUUM
-  rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
-  if( rc ){
-    return rc;
+  sqlite3BtreeEnter(p);
+  rc = saveAllCursors(pBt, 0, 0);
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  if( rc!=SQLITE_OK ){
+    /* This is a horrible situation. An IO or malloc() error occurred whilst
+    ** trying to save cursor positions. If this is an automatic rollback (as
+    ** the result of a constraint, malloc() failure or IO error) then 
+    ** the cache may be internally inconsistent (not contain valid trees) so
+    ** we cannot simply return the error to the caller. Instead, abort 
+    ** all queries that may be using any of the cursors that failed to save.
+    */
+    sqlite3BtreeTripAllCursors(p, rc);
   }
-#else
-  if( pBt->autoVacuum ){
-    Pgno pgnoMove;      /* Move a page here to make room for the root-page */
-    MemPage *pPageMove; /* The page to move to. */
+#endif
+  btreeIntegrity(p);
 
-    /* Creating a new table may probably require moving an existing database
-    ** to make room for the new tables root page. In case this page turns
-    ** out to be an overflow page, delete all overflow page-map caches
-    ** held by open cursors.
-    */
-    invalidateAllOverflowCache(pBt);
+  if( p->inTrans==TRANS_WRITE ){
+    int rc2;
 
-    /* Read the value of meta[3] from the database to determine where the
-    ** root page of the new table should go. meta[3] is the largest root-page
-    ** created so far, so the new root-page is (meta[3]+1).
-    */
-    rc = sqlite3BtreeGetMeta(p, 4, &pgnoRoot);
-    if( rc!=SQLITE_OK ){
-      return rc;
+    assert( TRANS_WRITE==pBt->inTransaction );
+    rc2 = sqlite3PagerRollback(pBt->pPager);
+    if( rc2!=SQLITE_OK ){
+      rc = rc2;
     }
-    pgnoRoot++;
 
-    /* The new root-page may not be allocated on a pointer-map page, or the
-    ** PENDING_BYTE page.
-    */
-    while( pgnoRoot==PTRMAP_PAGENO(pBt, pgnoRoot) ||
-        pgnoRoot==PENDING_BYTE_PAGE(pBt) ){
-      pgnoRoot++;
+    /* The rollback may have destroyed the pPage1->aData value.  So
+    ** call btreeGetPage() on page 1 again to make
+    ** sure pPage1->aData is set correctly. */
+    if( btreeGetPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
+      releasePage(pPage1);
     }
-    assert( pgnoRoot>=3 );
+    assert( countWriteCursors(pBt)==0 );
+    pBt->inTransaction = TRANS_READ;
+  }
 
-    /* Allocate a page. The page that currently resides at pgnoRoot will
-    ** be moved to the allocated page (unless the allocated page happens
-    ** to reside at pgnoRoot).
+  btreeEndTransaction(p);
+  sqlite3BtreeLeave(p);
+  return rc;
+}
+
+/*
+** Start a statement subtransaction. The subtransaction can can be rolled
+** back independently of the main transaction. You must start a transaction 
+** before starting a subtransaction. The subtransaction is ended automatically 
+** if the main transaction commits or rolls back.
+**
+** Statement subtransactions are used around individual SQL statements
+** that are contained within a BEGIN...COMMIT block.  If a constraint
+** error occurs within the statement, the effect of that one statement
+** can be rolled back without having to rollback the entire transaction.
+**
+** A statement sub-transaction is implemented as an anonymous savepoint. The
+** value passed as the second parameter is the total number of savepoints,
+** including the new anonymous savepoint, open on the B-Tree. i.e. if there
+** are no active savepoints and no other statement-transactions open,
+** iStatement is 1. This anonymous savepoint can be released or rolled back
+** using the sqlite3BtreeSavepoint() function.
+*/
+SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree *p, int iStatement){
+  int rc;
+  BtShared *pBt = p->pBt;
+  sqlite3BtreeEnter(p);
+  assert( p->inTrans==TRANS_WRITE );
+  assert( pBt->readOnly==0 );
+  assert( iStatement>0 );
+  assert( iStatement>p->db->nSavepoint );
+  if( NEVER(p->inTrans!=TRANS_WRITE || pBt->readOnly) ){
+    rc = SQLITE_INTERNAL;
+  }else{
+    assert( pBt->inTransaction==TRANS_WRITE );
+    /* At the pager level, a statement transaction is a savepoint with
+    ** an index greater than all savepoints created explicitly using
+    ** SQL statements. It is illegal to open, release or rollback any
+    ** such savepoints while the statement transaction savepoint is active.
     */
-    rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
-    if( rc!=SQLITE_OK ){
-      return rc;
+    rc = sqlite3PagerOpenSavepoint(pBt->pPager, iStatement);
+  }
+  sqlite3BtreeLeave(p);
+  return rc;
+}
+
+/*
+** The second argument to this function, op, is always SAVEPOINT_ROLLBACK
+** or SAVEPOINT_RELEASE. This function either releases or rolls back the
+** savepoint identified by parameter iSavepoint, depending on the value 
+** of op.
+**
+** Normally, iSavepoint is greater than or equal to zero. However, if op is
+** SAVEPOINT_ROLLBACK, then iSavepoint may also be -1. In this case the 
+** contents of the entire transaction are rolled back. This is different
+** from a normal transaction rollback, as no locks are released and the
+** transaction remains open.
+*/
+SQLITE_PRIVATE int sqlite3BtreeSavepoint(Btree *p, int op, int iSavepoint){
+  int rc = SQLITE_OK;
+  if( p && p->inTrans==TRANS_WRITE ){
+    BtShared *pBt = p->pBt;
+    assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
+    assert( iSavepoint>=0 || (iSavepoint==-1 && op==SAVEPOINT_ROLLBACK) );
+    sqlite3BtreeEnter(p);
+    rc = sqlite3PagerSavepoint(pBt->pPager, op, iSavepoint);
+    if( rc==SQLITE_OK ){
+      rc = newDatabase(pBt);
     }
+    sqlite3BtreeLeave(p);
+  }
+  return rc;
+}
 
-    if( pgnoMove!=pgnoRoot ){
-      /* pgnoRoot is the page that will be used for the root-page of
-      ** the new table (assuming an error did not occur). But we were
-      ** allocated pgnoMove. If required (i.e. if it was not allocated
-      ** by extending the file), the current page at position pgnoMove
-      ** is already journaled.
-      */
-      u8 eType;
-      Pgno iPtrPage;
+/*
+** Create a new cursor for the BTree whose root is on the page
+** iTable. If a read-only cursor is requested, it is assumed that
+** the caller already has at least a read-only transaction open
+** on the database already. If a write-cursor is requested, then
+** the caller is assumed to have an open write transaction.
+**
+** If wrFlag==0, then the cursor can only be used for reading.
+** If wrFlag==1, then the cursor can be used for reading or for
+** writing if other conditions for writing are also met.  These
+** are the conditions that must be met in order for writing to
+** be allowed:
+**
+** 1:  The cursor must have been opened with wrFlag==1
+**
+** 2:  Other database connections that share the same pager cache
+**     but which are not in the READ_UNCOMMITTED state may not have
+**     cursors open with wrFlag==0 on the same table.  Otherwise
+**     the changes made by this write cursor would be visible to
+**     the read cursors in the other database connection.
+**
+** 3:  The database must be writable (not on read-only media)
+**
+** 4:  There must be an active transaction.
+**
+** No checking is done to make sure that page iTable really is the
+** root page of a b-tree.  If it is not, then the cursor acquired
+** will not work correctly.
+**
+** It is assumed that the sqlite3BtreeCursorSize() bytes of memory 
+** pointed to by pCur have been zeroed by the caller.
+*/
+static int btreeCursor(
+  Btree *p,                              /* The btree */
+  int iTable,                            /* Root page of table to open */
+  int wrFlag,                            /* 1 to write. 0 read-only */
+  struct KeyInfo *pKeyInfo,              /* First arg to comparison function */
+  BtCursor *pCur                         /* Space for new cursor */
+){
+  BtShared *pBt = p->pBt;                /* Shared b-tree handle */
 
-      releasePage(pPageMove);
+  assert( sqlite3BtreeHoldsMutex(p) );
+  assert( wrFlag==0 || wrFlag==1 );
 
-      /* Move the page currently at pgnoRoot to pgnoMove. */
-      rc = sqlite3BtreeGetPage(pBt, pgnoRoot, &pRoot, 0);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-      rc = ptrmapGet(pBt, pgnoRoot, &eType, &iPtrPage);
-      if( rc!=SQLITE_OK || eType==PTRMAP_ROOTPAGE || eType==PTRMAP_FREEPAGE ){
-        releasePage(pRoot);
-        return rc;
-      }
-      assert( eType!=PTRMAP_ROOTPAGE );
-      assert( eType!=PTRMAP_FREEPAGE );
-      rc = sqlite3PagerWrite(pRoot->pDbPage);
-      if( rc!=SQLITE_OK ){
-        releasePage(pRoot);
-        return rc;
-      }
-      rc = relocatePage(pBt, pRoot, eType, iPtrPage, pgnoMove);
-      releasePage(pRoot);
+  /* The following assert statements verify that if this is a sharable 
+  ** b-tree database, the connection is holding the required table locks, 
+  ** and that no other connection has any open cursor that conflicts with 
+  ** this lock.  */
+  assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, wrFlag+1) );
+  assert( wrFlag==0 || !hasReadConflicts(p, iTable) );
 
-      /* Obtain the page at pgnoRoot */
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-      rc = sqlite3BtreeGetPage(pBt, pgnoRoot, &pRoot, 0);
-      if( rc!=SQLITE_OK ){
-        return rc;
-      }
-      rc = sqlite3PagerWrite(pRoot->pDbPage);
-      if( rc!=SQLITE_OK ){
-        releasePage(pRoot);
-        return rc;
-      }
-    }else{
-      pRoot = pPageMove;
-    } 
+  /* Assert that the caller has opened the required transaction. */
+  assert( p->inTrans>TRANS_NONE );
+  assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
+  assert( pBt->pPage1 && pBt->pPage1->aData );
 
-    /* Update the pointer-map and meta-data with the new root-page number. */
-    rc = ptrmapPut(pBt, pgnoRoot, PTRMAP_ROOTPAGE, 0);
-    if( rc ){
-      releasePage(pRoot);
-      return rc;
-    }
-    rc = sqlite3BtreeUpdateMeta(p, 4, pgnoRoot);
-    if( rc ){
-      releasePage(pRoot);
-      return rc;
-    }
+  if( NEVER(wrFlag && pBt->readOnly) ){
+    return SQLITE_READONLY;
+  }
+  if( iTable==1 && pagerPagecount(pBt)==0 ){
+    return SQLITE_EMPTY;
+  }
 
-  }else{
-    rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
-    if( rc ) return rc;
+  /* Now that no other errors can occur, finish filling in the BtCursor
+  ** variables and link the cursor into the BtShared list.  */
+  pCur->pgnoRoot = (Pgno)iTable;
+  pCur->iPage = -1;
+  pCur->pKeyInfo = pKeyInfo;
+  pCur->pBtree = p;
+  pCur->pBt = pBt;
+  pCur->wrFlag = (u8)wrFlag;
+  pCur->pNext = pBt->pCursor;
+  if( pCur->pNext ){
+    pCur->pNext->pPrev = pCur;
   }
-#endif
-  assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
-  zeroPage(pRoot, flags | PTF_LEAF);
-  sqlite3PagerUnref(pRoot->pDbPage);
-  *piTable = (int)pgnoRoot;
+  pBt->pCursor = pCur;
+  pCur->eState = CURSOR_INVALID;
+  pCur->cachedRowid = 0;
   return SQLITE_OK;
 }
-SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree *p, int *piTable, int flags){
+SQLITE_PRIVATE int sqlite3BtreeCursor(
+  Btree *p,                                   /* The btree */
+  int iTable,                                 /* Root page of table to open */
+  int wrFlag,                                 /* 1 to write. 0 read-only */
+  struct KeyInfo *pKeyInfo,                   /* First arg to xCompare() */
+  BtCursor *pCur                              /* Write new cursor here */
+){
   int rc;
   sqlite3BtreeEnter(p);
-  p->pBt->db = p->db;
-  rc = btreeCreateTable(p, piTable, flags);
+  rc = btreeCursor(p, iTable, wrFlag, pKeyInfo, pCur);
   sqlite3BtreeLeave(p);
   return rc;
 }
 
 /*
-** Erase the given database page and all its children.  Return
-** the page to the freelist.
+** Return the size of a BtCursor object in bytes.
+**
+** This interfaces is needed so that users of cursors can preallocate
+** sufficient storage to hold a cursor.  The BtCursor object is opaque
+** to users so they cannot do the sizeof() themselves - they must call
+** this routine.
 */
-static int clearDatabasePage(
-  BtShared *pBt,           /* The BTree that contains the table */
-  Pgno pgno,            /* Page number to clear */
-  MemPage *pParent,     /* Parent page.  NULL for the root */
-  int freePageFlag      /* Deallocate page if true */
-){
-  MemPage *pPage = 0;
-  int rc;
-  unsigned char *pCell;
-  int i;
+SQLITE_PRIVATE int sqlite3BtreeCursorSize(void){
+  return sizeof(BtCursor);
+}
 
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  if( pgno>sqlite3PagerPagecount(pBt->pPager) ){
-    return SQLITE_CORRUPT_BKPT;
+/*
+** Set the cached rowid value of every cursor in the same database file
+** as pCur and having the same root page number as pCur.  The value is
+** set to iRowid.
+**
+** Only positive rowid values are considered valid for this cache.
+** The cache is initialized to zero, indicating an invalid cache.
+** A btree will work fine with zero or negative rowids.  We just cannot
+** cache zero or negative rowids, which means tables that use zero or
+** negative rowids might run a little slower.  But in practice, zero
+** or negative rowids are very uncommon so this should not be a problem.
+*/
+SQLITE_PRIVATE void sqlite3BtreeSetCachedRowid(BtCursor *pCur, sqlite3_int64 iRowid){
+  BtCursor *p;
+  for(p=pCur->pBt->pCursor; p; p=p->pNext){
+    if( p->pgnoRoot==pCur->pgnoRoot ) p->cachedRowid = iRowid;
   }
+  assert( pCur->cachedRowid==iRowid );
+}
 
-  rc = getAndInitPage(pBt, pgno, &pPage, pParent);
-  if( rc ) goto cleardatabasepage_out;
-  for(i=0; i<pPage->nCell; i++){
-    pCell = findCell(pPage, i);
-    if( !pPage->leaf ){
-      rc = clearDatabasePage(pBt, get4byte(pCell), pPage->pParent, 1);
-      if( rc ) goto cleardatabasepage_out;
+/*
+** Return the cached rowid for the given cursor.  A negative or zero
+** return value indicates that the rowid cache is invalid and should be
+** ignored.  If the rowid cache has never before been set, then a
+** zero is returned.
+*/
+SQLITE_PRIVATE sqlite3_int64 sqlite3BtreeGetCachedRowid(BtCursor *pCur){
+  return pCur->cachedRowid;
+}
+
+/*
+** Close a cursor.  The read lock on the database file is released
+** when the last cursor is closed.
+*/
+SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor *pCur){
+  Btree *pBtree = pCur->pBtree;
+  if( pBtree ){
+    int i;
+    BtShared *pBt = pCur->pBt;
+    sqlite3BtreeEnter(pBtree);
+    sqlite3BtreeClearCursor(pCur);
+    if( pCur->pPrev ){
+      pCur->pPrev->pNext = pCur->pNext;
+    }else{
+      pBt->pCursor = pCur->pNext;
     }
-    rc = clearCell(pPage, pCell);
-    if( rc ) goto cleardatabasepage_out;
+    if( pCur->pNext ){
+      pCur->pNext->pPrev = pCur->pPrev;
+    }
+    for(i=0; i<=pCur->iPage; i++){
+      releasePage(pCur->apPage[i]);
+    }
+    unlockBtreeIfUnused(pBt);
+    invalidateOverflowCache(pCur);
+    /* sqlite3_free(pCur); */
+    sqlite3BtreeLeave(pBtree);
   }
-  if( !pPage->leaf ){
-    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), pPage->pParent, 1);
-    if( rc ) goto cleardatabasepage_out;
+  return SQLITE_OK;
+}
+
+/*
+** Make sure the BtCursor* given in the argument has a valid
+** BtCursor.info structure.  If it is not already valid, call
+** btreeParseCell() to fill it in.
+**
+** BtCursor.info is a cache of the information in the current cell.
+** Using this cache reduces the number of calls to btreeParseCell().
+**
+** 2007-06-25:  There is a bug in some versions of MSVC that cause the
+** compiler to crash when getCellInfo() is implemented as a macro.
+** But there is a measureable speed advantage to using the macro on gcc
+** (when less compiler optimizations like -Os or -O0 are used and the
+** compiler is not doing agressive inlining.)  So we use a real function
+** for MSVC and a macro for everything else.  Ticket #2457.
+*/
+#ifndef NDEBUG
+  static void assertCellInfo(BtCursor *pCur){
+    CellInfo info;
+    int iPage = pCur->iPage;
+    memset(&info, 0, sizeof(info));
+    btreeParseCell(pCur->apPage[iPage], pCur->aiIdx[iPage], &info);
+    assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
   }
-  if( freePageFlag ){
-    rc = freePage(pPage);
-  }else if( (rc = sqlite3PagerWrite(pPage->pDbPage))==0 ){
-    zeroPage(pPage, pPage->aData[0] | PTF_LEAF);
+#else
+  #define assertCellInfo(x)
+#endif
+#ifdef _MSC_VER
+  /* Use a real function in MSVC to work around bugs in that compiler. */
+  static void getCellInfo(BtCursor *pCur){
+    if( pCur->info.nSize==0 ){
+      int iPage = pCur->iPage;
+      btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);
+      pCur->validNKey = 1;
+    }else{
+      assertCellInfo(pCur);
+    }
+  }
+#else /* if not _MSC_VER */
+  /* Use a macro in all other compilers so that the function is inlined */
+#define getCellInfo(pCur)                                                      \
+  if( pCur->info.nSize==0 ){                                                   \
+    int iPage = pCur->iPage;                                                   \
+    btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \
+    pCur->validNKey = 1;                                                       \
+  }else{                                                                       \
+    assertCellInfo(pCur);                                                      \
   }
+#endif /* _MSC_VER */
 
-cleardatabasepage_out:
-  releasePage(pPage);
-  return rc;
+#ifndef NDEBUG  /* The next routine used only within assert() statements */
+/*
+** Return true if the given BtCursor is valid.  A valid cursor is one
+** that is currently pointing to a row in a (non-empty) table.
+** This is a verification routine is used only within assert() statements.
+*/
+SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor *pCur){
+  return pCur && pCur->eState==CURSOR_VALID;
 }
+#endif /* NDEBUG */
 
 /*
-** Delete all information from a single table in the database.  iTable is
-** the page number of the root of the table.  After this routine returns,
-** the root page is empty, but still exists.
+** Set *pSize to the size of the buffer needed to hold the value of
+** the key for the current entry.  If the cursor is not pointing
+** to a valid entry, *pSize is set to 0. 
 **
-** This routine will fail with SQLITE_LOCKED if there are any open
-** read cursors on the table.  Open write cursors are moved to the
-** root of the table.
+** For a table with the INTKEY flag set, this routine returns the key
+** itself, not the number of bytes in the key.
+**
+** The caller must position the cursor prior to invoking this routine.
+** 
+** This routine cannot fail.  It always returns SQLITE_OK.  
 */
-SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree *p, int iTable){
-  int rc;
-  BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  if( p->inTrans!=TRANS_WRITE ){
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-  }else if( (rc = checkReadLocks(p, iTable, 0))!=SQLITE_OK ){
-    /* nothing to do */
-  }else if( SQLITE_OK!=(rc = saveAllCursors(pBt, iTable, 0)) ){
-    /* nothing to do */
+SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
+  if( pCur->eState!=CURSOR_VALID ){
+    *pSize = 0;
   }else{
-    rc = clearDatabasePage(pBt, (Pgno)iTable, 0, 0);
+    getCellInfo(pCur);
+    *pSize = pCur->info.nKey;
   }
-  sqlite3BtreeLeave(p);
-  return rc;
+  return SQLITE_OK;
 }
 
 /*
-** Erase all information in a table and add the root of the table to
-** the freelist.  Except, the root of the principle table (the one on
-** page 1) is never added to the freelist.
+** Set *pSize to the number of bytes of data in the entry the
+** cursor currently points to.
 **
-** This routine will fail with SQLITE_LOCKED if there are any open
-** cursors on the table.
+** The caller must guarantee that the cursor is pointing to a non-NULL
+** valid entry.  In other words, the calling procedure must guarantee
+** that the cursor has Cursor.eState==CURSOR_VALID.
 **
-** If AUTOVACUUM is enabled and the page at iTable is not the last
-** root page in the database file, then the last root page 
-** in the database file is moved into the slot formerly occupied by
-** iTable and that last slot formerly occupied by the last root page
-** is added to the freelist instead of iTable.  In this say, all
-** root pages are kept at the beginning of the database file, which
-** is necessary for AUTOVACUUM to work right.  *piMoved is set to the 
-** page number that used to be the last root page in the file before
-** the move.  If no page gets moved, *piMoved is set to 0.
-** The last root page is recorded in meta[3] and the value of
-** meta[3] is updated by this procedure.
+** Failure is not possible.  This function always returns SQLITE_OK.
+** It might just as well be a procedure (returning void) but we continue
+** to return an integer result code for historical reasons.
 */
-static int btreeDropTable(Btree *p, int iTable, int *piMoved){
-  int rc;
+SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  getCellInfo(pCur);
+  *pSize = pCur->info.nData;
+  return SQLITE_OK;
+}
+
+/*
+** Given the page number of an overflow page in the database (parameter
+** ovfl), this function finds the page number of the next page in the 
+** linked list of overflow pages. If possible, it uses the auto-vacuum
+** pointer-map data instead of reading the content of page ovfl to do so. 
+**
+** If an error occurs an SQLite error code is returned. Otherwise:
+**
+** The page number of the next overflow page in the linked list is 
+** written to *pPgnoNext. If page ovfl is the last page in its linked 
+** list, *pPgnoNext is set to zero. 
+**
+** If ppPage is not NULL, and a reference to the MemPage object corresponding
+** to page number pOvfl was obtained, then *ppPage is set to point to that
+** reference. It is the responsibility of the caller to call releasePage()
+** on *ppPage to free the reference. In no reference was obtained (because
+** the pointer-map was used to obtain the value for *pPgnoNext), then
+** *ppPage is set to zero.
+*/
+static int getOverflowPage(
+  BtShared *pBt,               /* The database file */
+  Pgno ovfl,                   /* Current overflow page number */
+  MemPage **ppPage,            /* OUT: MemPage handle (may be NULL) */
+  Pgno *pPgnoNext              /* OUT: Next overflow page number */
+){
+  Pgno next = 0;
   MemPage *pPage = 0;
-  BtShared *pBt = p->pBt;
+  int rc = SQLITE_OK;
 
-  assert( sqlite3BtreeHoldsMutex(p) );
-  if( p->inTrans!=TRANS_WRITE ){
-    return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-  }
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert(pPgnoNext);
 
-  /* It is illegal to drop a table if any cursors are open on the
-  ** database. This is because in auto-vacuum mode the backend may
-  ** need to move another root-page to fill a gap left by the deleted
-  ** root page. If an open cursor was using this page a problem would 
-  ** occur.
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  /* Try to find the next page in the overflow list using the
+  ** autovacuum pointer-map pages. Guess that the next page in 
+  ** the overflow list is page number (ovfl+1). If that guess turns 
+  ** out to be wrong, fall back to loading the data of page 
+  ** number ovfl to determine the next page number.
   */
-  if( pBt->pCursor ){
-    return SQLITE_LOCKED;
-  }
-
-  rc = sqlite3BtreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
-  if( rc ) return rc;
-  rc = sqlite3BtreeClearTable(p, iTable);
-  if( rc ){
-    releasePage(pPage);
-    return rc;
-  }
-
-  *piMoved = 0;
-
-  if( iTable>1 ){
-#ifdef SQLITE_OMIT_AUTOVACUUM
-    rc = freePage(pPage);
-    releasePage(pPage);
-#else
-    if( pBt->autoVacuum ){
-      Pgno maxRootPgno;
-      rc = sqlite3BtreeGetMeta(p, 4, &maxRootPgno);
-      if( rc!=SQLITE_OK ){
-        releasePage(pPage);
-        return rc;
-      }
+  if( pBt->autoVacuum ){
+    Pgno pgno;
+    Pgno iGuess = ovfl+1;
+    u8 eType;
 
-      if( iTable==maxRootPgno ){
-        /* If the table being dropped is the table with the largest root-page
-        ** number in the database, put the root page on the free list. 
-        */
-        rc = freePage(pPage);
-        releasePage(pPage);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-      }else{
-        /* The table being dropped does not have the largest root-page
-        ** number in the database. So move the page that does into the 
-        ** gap left by the deleted root-page.
-        */
-        MemPage *pMove;
-        releasePage(pPage);
-        rc = sqlite3BtreeGetPage(pBt, maxRootPgno, &pMove, 0);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable);
-        releasePage(pMove);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        rc = sqlite3BtreeGetPage(pBt, maxRootPgno, &pMove, 0);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        rc = freePage(pMove);
-        releasePage(pMove);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        *piMoved = maxRootPgno;
-      }
+    while( PTRMAP_ISPAGE(pBt, iGuess) || iGuess==PENDING_BYTE_PAGE(pBt) ){
+      iGuess++;
+    }
 
-      /* Set the new 'max-root-page' value in the database header. This
-      ** is the old value less one, less one more if that happens to
-      ** be a root-page number, less one again if that is the
-      ** PENDING_BYTE_PAGE.
-      */
-      maxRootPgno--;
-      if( maxRootPgno==PENDING_BYTE_PAGE(pBt) ){
-        maxRootPgno--;
-      }
-      if( maxRootPgno==PTRMAP_PAGENO(pBt, maxRootPgno) ){
-        maxRootPgno--;
+    if( iGuess<=pagerPagecount(pBt) ){
+      rc = ptrmapGet(pBt, iGuess, &eType, &pgno);
+      if( rc==SQLITE_OK && eType==PTRMAP_OVERFLOW2 && pgno==ovfl ){
+        next = iGuess;
+        rc = SQLITE_DONE;
       }
-      assert( maxRootPgno!=PENDING_BYTE_PAGE(pBt) );
-
-      rc = sqlite3BtreeUpdateMeta(p, 4, maxRootPgno);
-    }else{
-      rc = freePage(pPage);
-      releasePage(pPage);
     }
+  }
 #endif
+
+  assert( next==0 || rc==SQLITE_DONE );
+  if( rc==SQLITE_OK ){
+    rc = btreeGetPage(pBt, ovfl, &pPage, 0);
+    assert( rc==SQLITE_OK || pPage==0 );
+    if( rc==SQLITE_OK ){
+      next = get4byte(pPage->aData);
+    }
+  }
+
+  *pPgnoNext = next;
+  if( ppPage ){
+    *ppPage = pPage;
   }else{
-    /* If sqlite3BtreeDropTable was called on page 1. */
-    zeroPage(pPage, PTF_INTKEY|PTF_LEAF );
     releasePage(pPage);
   }
-  return rc;  
-}
-SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
-  int rc;
-  sqlite3BtreeEnter(p);
-  p->pBt->db = p->db;
-  rc = btreeDropTable(p, iTable, piMoved);
-  sqlite3BtreeLeave(p);
-  return rc;
+  return (rc==SQLITE_DONE ? SQLITE_OK : rc);
 }
 
+/*
+** Copy data from a buffer to a page, or from a page to a buffer.
+**
+** pPayload is a pointer to data stored on database page pDbPage.
+** If argument eOp is false, then nByte bytes of data are copied
+** from pPayload to the buffer pointed at by pBuf. If eOp is true,
+** then sqlite3PagerWrite() is called on pDbPage and nByte bytes
+** of data are copied from the buffer pBuf to pPayload.
+**
+** SQLITE_OK is returned on success, otherwise an error code.
+*/
+static int copyPayload(
+  void *pPayload,           /* Pointer to page data */
+  void *pBuf,               /* Pointer to buffer */
+  int nByte,                /* Number of bytes to copy */
+  int eOp,                  /* 0 -> copy from page, 1 -> copy to page */
+  DbPage *pDbPage           /* Page containing pPayload */
+){
+  if( eOp ){
+    /* Copy data from buffer to page (a write operation) */
+    int rc = sqlite3PagerWrite(pDbPage);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    memcpy(pPayload, pBuf, nByte);
+  }else{
+    /* Copy data from page to buffer (a read operation) */
+    memcpy(pBuf, pPayload, nByte);
+  }
+  return SQLITE_OK;
+}
 
 /*
-** Read the meta-information out of a database file.  Meta[0]
-** is the number of free pages currently in the database.  Meta[1]
-** through meta[15] are available for use by higher layers.  Meta[0]
-** is read-only, the others are read/write.
-** 
-** The schema layer numbers meta values differently.  At the schema
-** layer (and the SetCookie and ReadCookie opcodes) the number of
-** free pages is not visible.  So Cookie[0] is the same as Meta[1].
+** This function is used to read or overwrite payload information
+** for the entry that the pCur cursor is pointing to. If the eOp
+** parameter is 0, this is a read operation (data copied into
+** buffer pBuf). If it is non-zero, a write (data copied from
+** buffer pBuf).
+**
+** A total of "amt" bytes are read or written beginning at "offset".
+** Data is read to or from the buffer pBuf.
+**
+** The content being read or written might appear on the main page
+** or be scattered out on multiple overflow pages.
+**
+** If the BtCursor.isIncrblobHandle flag is set, and the current
+** cursor entry uses one or more overflow pages, this function
+** allocates space for and lazily popluates the overflow page-list 
+** cache array (BtCursor.aOverflow). Subsequent calls use this
+** cache to make seeking to the supplied offset more efficient.
+**
+** Once an overflow page-list cache has been allocated, it may be
+** invalidated if some other cursor writes to the same table, or if
+** the cursor is moved to a different row. Additionally, in auto-vacuum
+** mode, the following events may invalidate an overflow page-list cache.
+**
+**   * An incremental vacuum,
+**   * A commit in auto_vacuum="full" mode,
+**   * Creating a table (may require moving an overflow page).
 */
-SQLITE_PRIVATE int sqlite3BtreeGetMeta(Btree *p, int idx, u32 *pMeta){
-  DbPage *pDbPage;
-  int rc;
-  unsigned char *pP1;
-  BtShared *pBt = p->pBt;
+static int accessPayload(
+  BtCursor *pCur,      /* Cursor pointing to entry to read from */
+  u32 offset,          /* Begin reading this far into payload */
+  u32 amt,             /* Read this many bytes */
+  unsigned char *pBuf, /* Write the bytes into this buffer */ 
+  int eOp              /* zero to read. non-zero to write. */
+){
+  unsigned char *aPayload;
+  int rc = SQLITE_OK;
+  u32 nKey;
+  int iIdx = 0;
+  MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
+  BtShared *pBt = pCur->pBt;                  /* Btree this cursor belongs to */
 
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
+  assert( pPage );
+  assert( pCur->eState==CURSOR_VALID );
+  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
+  assert( cursorHoldsMutex(pCur) );
 
-  /* Reading a meta-data value requires a read-lock on page 1 (and hence
-  ** the sqlite_master table. We grab this lock regardless of whether or
-  ** not the SQLITE_ReadUncommitted flag is set (the table rooted at page
-  ** 1 is treated as a special case by queryTableLock() and lockTable()).
-  */
-  rc = queryTableLock(p, 1, READ_LOCK);
-  if( rc!=SQLITE_OK ){
-    sqlite3BtreeLeave(p);
-    return rc;
+  getCellInfo(pCur);
+  aPayload = pCur->info.pCell + pCur->info.nHeader;
+  nKey = (pPage->intKey ? 0 : (int)pCur->info.nKey);
+
+  if( NEVER(offset+amt > nKey+pCur->info.nData) 
+   || &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize]
+  ){
+    /* Trying to read or write past the end of the data is an error */
+    return SQLITE_CORRUPT_BKPT;
   }
 
-  assert( idx>=0 && idx<=15 );
-  rc = sqlite3PagerGet(pBt->pPager, 1, &pDbPage);
-  if( rc ){
-    sqlite3BtreeLeave(p);
-    return rc;
+  /* Check if data must be read/written to/from the btree page itself. */
+  if( offset<pCur->info.nLocal ){
+    int a = amt;
+    if( a+offset>pCur->info.nLocal ){
+      a = pCur->info.nLocal - offset;
+    }
+    rc = copyPayload(&aPayload[offset], pBuf, a, eOp, pPage->pDbPage);
+    offset = 0;
+    pBuf += a;
+    amt -= a;
+  }else{
+    offset -= pCur->info.nLocal;
   }
-  pP1 = (unsigned char *)sqlite3PagerGetData(pDbPage);
-  *pMeta = get4byte(&pP1[36 + idx*4]);
-  sqlite3PagerUnref(pDbPage);
 
-  /* If autovacuumed is disabled in this build but we are trying to 
-  ** access an autovacuumed database, then make the database readonly. 
-  */
-#ifdef SQLITE_OMIT_AUTOVACUUM
-  if( idx==4 && *pMeta>0 ) pBt->readOnly = 1;
+  if( rc==SQLITE_OK && amt>0 ){
+    const u32 ovflSize = pBt->usableSize - 4;  /* Bytes content per ovfl page */
+    Pgno nextPage;
+
+    nextPage = get4byte(&aPayload[pCur->info.nLocal]);
+
+#ifndef SQLITE_OMIT_INCRBLOB
+    /* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
+    ** has not been allocated, allocate it now. The array is sized at
+    ** one entry for each overflow page in the overflow chain. The
+    ** page number of the first overflow page is stored in aOverflow[0],
+    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
+    ** (the cache is lazily populated).
+    */
+    if( pCur->isIncrblobHandle && !pCur->aOverflow ){
+      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
+      pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
+      /* nOvfl is always positive.  If it were zero, fetchPayload would have
+      ** been used instead of this routine. */
+      if( ALWAYS(nOvfl) && !pCur->aOverflow ){
+        rc = SQLITE_NOMEM;
+      }
+    }
+
+    /* If the overflow page-list cache has been allocated and the
+    ** entry for the first required overflow page is valid, skip
+    ** directly to it.
+    */
+    if( pCur->aOverflow && pCur->aOverflow[offset/ovflSize] ){
+      iIdx = (offset/ovflSize);
+      nextPage = pCur->aOverflow[iIdx];
+      offset = (offset%ovflSize);
+    }
 #endif
 
-  /* Grab the read-lock on page 1. */
-  rc = lockTable(p, 1, READ_LOCK);
-  sqlite3BtreeLeave(p);
-  return rc;
-}
+    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){
 
-/*
-** Write meta-information back into the database.  Meta[0] is
-** read-only and may not be written.
-*/
-SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree *p, int idx, u32 iMeta){
-  BtShared *pBt = p->pBt;
-  unsigned char *pP1;
-  int rc;
-  assert( idx>=1 && idx<=15 );
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  if( p->inTrans!=TRANS_WRITE ){
-    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
-  }else{
-    assert( pBt->pPage1!=0 );
-    pP1 = pBt->pPage1->aData;
-    rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
-    if( rc==SQLITE_OK ){
-      put4byte(&pP1[36 + idx*4], iMeta);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( idx==7 ){
-        assert( pBt->autoVacuum || iMeta==0 );
-        assert( iMeta==0 || iMeta==1 );
-        pBt->incrVacuum = iMeta;
+#ifndef SQLITE_OMIT_INCRBLOB
+      /* If required, populate the overflow page-list cache. */
+      if( pCur->aOverflow ){
+        assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
+        pCur->aOverflow[iIdx] = nextPage;
       }
 #endif
+
+      if( offset>=ovflSize ){
+        /* The only reason to read this page is to obtain the page
+        ** number for the next page in the overflow chain. The page
+        ** data is not required. So first try to lookup the overflow
+        ** page-list cache, if any, then fall back to the getOverflowPage()
+        ** function.
+        */
+#ifndef SQLITE_OMIT_INCRBLOB
+        if( pCur->aOverflow && pCur->aOverflow[iIdx+1] ){
+          nextPage = pCur->aOverflow[iIdx+1];
+        } else 
+#endif
+          rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
+        offset -= ovflSize;
+      }else{
+        /* Need to read this page properly. It contains some of the
+        ** range of data that is being read (eOp==0) or written (eOp!=0).
+        */
+        DbPage *pDbPage;
+        int a = amt;
+        rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage);
+        if( rc==SQLITE_OK ){
+          aPayload = sqlite3PagerGetData(pDbPage);
+          nextPage = get4byte(aPayload);
+          if( a + offset > ovflSize ){
+            a = ovflSize - offset;
+          }
+          rc = copyPayload(&aPayload[offset+4], pBuf, a, eOp, pDbPage);
+          sqlite3PagerUnref(pDbPage);
+          offset = 0;
+          amt -= a;
+          pBuf += a;
+        }
+      }
     }
   }
-  sqlite3BtreeLeave(p);
+
+  if( rc==SQLITE_OK && amt>0 ){
+    return SQLITE_CORRUPT_BKPT;
+  }
   return rc;
 }
 
 /*
-** Return the flag byte at the beginning of the page that the cursor
-** is currently pointing to.
+** Read part of the key associated with cursor pCur.  Exactly
+** "amt" bytes will be transfered into pBuf[].  The transfer
+** begins at "offset".
+**
+** The caller must ensure that pCur is pointing to a valid row
+** in the table.
+**
+** Return SQLITE_OK on success or an error code if anything goes
+** wrong.  An error is returned if "offset+amt" is larger than
+** the available payload.
 */
-SQLITE_PRIVATE int sqlite3BtreeFlags(BtCursor *pCur){
-  /* TODO: What about CURSOR_REQUIRESEEK state? Probably need to call
-  ** restoreOrClearCursorPosition() here.
-  */
-  MemPage *pPage;
-  restoreOrClearCursorPosition(pCur);
-  pPage = pCur->pPage;
+SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
   assert( cursorHoldsMutex(pCur) );
-  assert( pPage->pBt==pCur->pBt );
-  return pPage ? pPage->aData[pPage->hdrOffset] : 0;
+  assert( pCur->eState==CURSOR_VALID );
+  assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
+  assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+  return accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0);
 }
 
-
 /*
-** Return the pager associated with a BTree.  This routine is used for
-** testing and debugging only.
+** Read part of the data associated with cursor pCur.  Exactly
+** "amt" bytes will be transfered into pBuf[].  The transfer
+** begins at "offset".
+**
+** Return SQLITE_OK on success or an error code if anything goes
+** wrong.  An error is returned if "offset+amt" is larger than
+** the available payload.
 */
-SQLITE_PRIVATE Pager *sqlite3BtreePager(Btree *p){
-  return p->pBt->pPager;
+SQLITE_PRIVATE int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
+  int rc;
+
+#ifndef SQLITE_OMIT_INCRBLOB
+  if ( pCur->eState==CURSOR_INVALID ){
+    return SQLITE_ABORT;
+  }
+#endif
+
+  assert( cursorHoldsMutex(pCur) );
+  rc = restoreCursorPosition(pCur);
+  if( rc==SQLITE_OK ){
+    assert( pCur->eState==CURSOR_VALID );
+    assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
+    assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+    rc = accessPayload(pCur, offset, amt, pBuf, 0);
+  }
+  return rc;
 }
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** Append a message to the error message string.
+** Return a pointer to payload information from the entry that the 
+** pCur cursor is pointing to.  The pointer is to the beginning of
+** the key if skipKey==0 and it points to the beginning of data if
+** skipKey==1.  The number of bytes of available key/data is written
+** into *pAmt.  If *pAmt==0, then the value returned will not be
+** a valid pointer.
+**
+** This routine is an optimization.  It is common for the entire key
+** and data to fit on the local page and for there to be no overflow
+** pages.  When that is so, this routine can be used to access the
+** key and data without making a copy.  If the key and/or data spills
+** onto overflow pages, then accessPayload() must be used to reassemble
+** the key/data and copy it into a preallocated buffer.
+**
+** The pointer returned by this routine looks directly into the cached
+** page of the database.  The data might change or move the next time
+** any btree routine is called.
 */
-static void checkAppendMsg(
-  IntegrityCk *pCheck,
-  char *zMsg1,
-  const char *zFormat,
-  ...
+static const unsigned char *fetchPayload(
+  BtCursor *pCur,      /* Cursor pointing to entry to read from */
+  int *pAmt,           /* Write the number of available bytes here */
+  int skipKey          /* read beginning at data if this is true */
 ){
-  va_list ap;
-  char *zMsg2;
-  if( !pCheck->mxErr ) return;
-  pCheck->mxErr--;
-  pCheck->nErr++;
-  va_start(ap, zFormat);
-  zMsg2 = sqlite3VMPrintf(0, zFormat, ap);
-  va_end(ap);
-  if( zMsg1==0 ) zMsg1 = "";
-  if( pCheck->zErrMsg ){
-    char *zOld = pCheck->zErrMsg;
-    pCheck->zErrMsg = 0;
-    sqlite3SetString(&pCheck->zErrMsg, zOld, "\n", zMsg1, zMsg2, (char*)0);
-    sqlite3_free(zOld);
+  unsigned char *aPayload;
+  MemPage *pPage;
+  u32 nKey;
+  u32 nLocal;
+
+  assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
+  assert( pCur->eState==CURSOR_VALID );
+  assert( cursorHoldsMutex(pCur) );
+  pPage = pCur->apPage[pCur->iPage];
+  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
+  if( NEVER(pCur->info.nSize==0) ){
+    btreeParseCell(pCur->apPage[pCur->iPage], pCur->aiIdx[pCur->iPage],
+                   &pCur->info);
+  }
+  aPayload = pCur->info.pCell;
+  aPayload += pCur->info.nHeader;
+  if( pPage->intKey ){
+    nKey = 0;
   }else{
-    sqlite3SetString(&pCheck->zErrMsg, zMsg1, zMsg2, (char*)0);
+    nKey = (int)pCur->info.nKey;
   }
-  sqlite3_free(zMsg2);
+  if( skipKey ){
+    aPayload += nKey;
+    nLocal = pCur->info.nLocal - nKey;
+  }else{
+    nLocal = pCur->info.nLocal;
+    assert( nLocal<=nKey );
+  }
+  *pAmt = nLocal;
+  return aPayload;
 }
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
+
 /*
-** Add 1 to the reference count for page iPage.  If this is the second
-** reference to the page, add an error message to pCheck->zErrMsg.
-** Return 1 if there are 2 ore more references to the page and 0 if
-** if this is the first reference to the page.
+** For the entry that cursor pCur is point to, return as
+** many bytes of the key or data as are available on the local
+** b-tree page.  Write the number of available bytes into *pAmt.
 **
-** Also check that the page number is in bounds.
+** The pointer returned is ephemeral.  The key/data may move
+** or be destroyed on the next call to any Btree routine,
+** including calls from other threads against the same cache.
+** Hence, a mutex on the BtShared should be held prior to calling
+** this routine.
+**
+** These routines is used to get quick access to key and data
+** in the common case where no overflow pages are used.
 */
-static int checkRef(IntegrityCk *pCheck, int iPage, char *zContext){
-  if( iPage==0 ) return 1;
-  if( iPage>pCheck->nPage || iPage<0 ){
-    checkAppendMsg(pCheck, zContext, "invalid page number %d", iPage);
-    return 1;
+SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor *pCur, int *pAmt){
+  const void *p = 0;
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  assert( cursorHoldsMutex(pCur) );
+  if( ALWAYS(pCur->eState==CURSOR_VALID) ){
+    p = (const void*)fetchPayload(pCur, pAmt, 0);
   }
-  if( pCheck->anRef[iPage]==1 ){
-    checkAppendMsg(pCheck, zContext, "2nd reference to page %d", iPage);
-    return 1;
+  return p;
+}
+SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor *pCur, int *pAmt){
+  const void *p = 0;
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  assert( cursorHoldsMutex(pCur) );
+  if( ALWAYS(pCur->eState==CURSOR_VALID) ){
+    p = (const void*)fetchPayload(pCur, pAmt, 1);
   }
-  return  (pCheck->anRef[iPage]++)>1;
+  return p;
 }
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
+
 /*
-** Check that the entry in the pointer-map for page iChild maps to 
-** page iParent, pointer type ptrType. If not, append an error message
-** to pCheck.
+** Move the cursor down to a new child page.  The newPgno argument is the
+** page number of the child page to move to.
+**
+** This function returns SQLITE_CORRUPT if the page-header flags field of
+** the new child page does not match the flags field of the parent (i.e.
+** if an intkey page appears to be the parent of a non-intkey page, or
+** vice-versa).
 */
-static void checkPtrmap(
-  IntegrityCk *pCheck,   /* Integrity check context */
-  Pgno iChild,           /* Child page number */
-  u8 eType,              /* Expected pointer map type */
-  Pgno iParent,          /* Expected pointer map parent page number */
-  char *zContext         /* Context description (used for error msg) */
-){
+static int moveToChild(BtCursor *pCur, u32 newPgno){
   int rc;
-  u8 ePtrmapType;
-  Pgno iPtrmapParent;
+  int i = pCur->iPage;
+  MemPage *pNewPage;
+  BtShared *pBt = pCur->pBt;
 
-  rc = ptrmapGet(pCheck->pBt, iChild, &ePtrmapType, &iPtrmapParent);
-  if( rc!=SQLITE_OK ){
-    checkAppendMsg(pCheck, zContext, "Failed to read ptrmap key=%d", iChild);
-    return;
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
+  if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
+    return SQLITE_CORRUPT_BKPT;
   }
+  rc = getAndInitPage(pBt, newPgno, &pNewPage);
+  if( rc ) return rc;
+  pCur->apPage[i+1] = pNewPage;
+  pCur->aiIdx[i+1] = 0;
+  pCur->iPage++;
 
-  if( ePtrmapType!=eType || iPtrmapParent!=iParent ){
-    checkAppendMsg(pCheck, zContext, 
-      "Bad ptr map entry key=%d expected=(%d,%d) got=(%d,%d)", 
-      iChild, eType, iParent, ePtrmapType, iPtrmapParent);
+  pCur->info.nSize = 0;
+  pCur->validNKey = 0;
+  if( pNewPage->nCell<1 || pNewPage->intKey!=pCur->apPage[i]->intKey ){
+    return SQLITE_CORRUPT_BKPT;
   }
+  return SQLITE_OK;
 }
-#endif
 
+#ifndef NDEBUG
 /*
-** Check the integrity of the freelist or of an overflow page list.
-** Verify that the number of pages on the list is N.
+** Page pParent is an internal (non-leaf) tree page. This function 
+** asserts that page number iChild is the left-child if the iIdx'th
+** cell in page pParent. Or, if iIdx is equal to the total number of
+** cells in pParent, that page number iChild is the right-child of
+** the page.
 */
-static void checkList(
-  IntegrityCk *pCheck,  /* Integrity checking context */
-  int isFreeList,       /* True for a freelist.  False for overflow page list */
-  int iPage,            /* Page number for first page in the list */
-  int N,                /* Expected number of pages in the list */
-  char *zContext        /* Context for error messages */
-){
-  int i;
-  int expected = N;
-  int iFirst = iPage;
-  while( N-- > 0 && pCheck->mxErr ){
-    DbPage *pOvflPage;
-    unsigned char *pOvflData;
-    if( iPage<1 ){
-      checkAppendMsg(pCheck, zContext,
-         "%d of %d pages missing from overflow list starting at %d",
-          N+1, expected, iFirst);
-      break;
-    }
-    if( checkRef(pCheck, iPage, zContext) ) break;
-    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage) ){
-      checkAppendMsg(pCheck, zContext, "failed to get page %d", iPage);
-      break;
-    }
-    pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
-    if( isFreeList ){
-      int n = get4byte(&pOvflData[4]);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( pCheck->pBt->autoVacuum ){
-        checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
-      }
-#endif
-      if( n>pCheck->pBt->usableSize/4-8 ){
-        checkAppendMsg(pCheck, zContext,
-           "freelist leaf count too big on page %d", iPage);
-        N--;
-      }else{
-        for(i=0; i<n; i++){
-          Pgno iFreePage = get4byte(&pOvflData[8+i*4]);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-          if( pCheck->pBt->autoVacuum ){
-            checkPtrmap(pCheck, iFreePage, PTRMAP_FREEPAGE, 0, zContext);
-          }
-#endif
-          checkRef(pCheck, iFreePage, zContext);
-        }
-        N -= n;
-      }
-    }
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    else{
-      /* If this database supports auto-vacuum and iPage is not the last
-      ** page in this overflow list, check that the pointer-map entry for
-      ** the following page matches iPage.
-      */
-      if( pCheck->pBt->autoVacuum && N>0 ){
-        i = get4byte(pOvflData);
-        checkPtrmap(pCheck, i, PTRMAP_OVERFLOW2, iPage, zContext);
-      }
-    }
-#endif
-    iPage = get4byte(pOvflData);
-    sqlite3PagerUnref(pOvflPage);
+static void assertParentIndex(MemPage *pParent, int iIdx, Pgno iChild){
+  assert( iIdx<=pParent->nCell );
+  if( iIdx==pParent->nCell ){
+    assert( get4byte(&pParent->aData[pParent->hdrOffset+8])==iChild );
+  }else{
+    assert( get4byte(findCell(pParent, iIdx))==iChild );
   }
 }
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
+#else
+#  define assertParentIndex(x,y,z) 
+#endif
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** Do various sanity checks on a single page of a tree.  Return
-** the tree depth.  Root pages return 0.  Parents of root pages
-** return 1, and so forth.
-** 
-** These checks are done:
+** Move the cursor up to the parent page.
 **
-**      1.  Make sure that cells and freeblocks do not overlap
-**          but combine to completely cover the page.
-**  NO  2.  Make sure cell keys are in order.
-**  NO  3.  Make sure no key is less than or equal to zLowerBound.
-**  NO  4.  Make sure no key is greater than or equal to zUpperBound.
-**      5.  Check the integrity of overflow pages.
-**      6.  Recursively call checkTreePage on all children.
-**      7.  Verify that the depth of all children is the same.
-**      8.  Make sure this page is at least 33% full or else it is
-**          the root of the tree.
+** pCur->idx is set to the cell index that contains the pointer
+** to the page we are coming from.  If we are coming from the
+** right-most child page then pCur->idx is set to one more than
+** the largest cell index.
 */
-static int checkTreePage(
-  IntegrityCk *pCheck,  /* Context for the sanity check */
-  int iPage,            /* Page number of the page to check */
-  MemPage *pParent,     /* Parent page */
-  char *zParentContext  /* Parent context */
-){
-  MemPage *pPage;
-  int i, rc, depth, d2, pgno, cnt;
-  int hdr, cellStart;
-  int nCell;
-  u8 *data;
-  BtShared *pBt;
-  int usableSize;
-  char zContext[100];
-  char *hit;
-
-  sqlite3_snprintf(sizeof(zContext), zContext, "Page %d: ", iPage);
-
-  /* Check that the page exists
-  */
-  pBt = pCheck->pBt;
-  usableSize = pBt->usableSize;
-  if( iPage==0 ) return 0;
-  if( checkRef(pCheck, iPage, zParentContext) ) return 0;
-  if( (rc = sqlite3BtreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
-    checkAppendMsg(pCheck, zContext,
-       "unable to get the page. error code=%d", rc);
-    return 0;
-  }
-  if( (rc = sqlite3BtreeInitPage(pPage, pParent))!=0 ){
-    checkAppendMsg(pCheck, zContext, 
-                   "sqlite3BtreeInitPage() returns error code %d", rc);
-    releasePage(pPage);
-    return 0;
-  }
-
-  /* Check out all the cells.
-  */
-  depth = 0;
-  for(i=0; i<pPage->nCell && pCheck->mxErr; i++){
-    u8 *pCell;
-    int sz;
-    CellInfo info;
-
-    /* Check payload overflow pages
-    */
-    sqlite3_snprintf(sizeof(zContext), zContext,
-             "On tree page %d cell %d: ", iPage, i);
-    pCell = findCell(pPage,i);
-    sqlite3BtreeParseCellPtr(pPage, pCell, &info);
-    sz = info.nData;
-    if( !pPage->intKey ) sz += info.nKey;
-    assert( sz==info.nPayload );
-    if( sz>info.nLocal ){
-      int nPage = (sz - info.nLocal + usableSize - 5)/(usableSize - 4);
-      Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( pBt->autoVacuum ){
-        checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage, zContext);
-      }
-#endif
-      checkList(pCheck, 0, pgnoOvfl, nPage, zContext);
-    }
-
-    /* Check sanity of left child page.
-    */
-    if( !pPage->leaf ){
-      pgno = get4byte(pCell);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-      if( pBt->autoVacuum ){
-        checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, zContext);
-      }
-#endif
-      d2 = checkTreePage(pCheck,pgno,pPage,zContext);
-      if( i>0 && d2!=depth ){
-        checkAppendMsg(pCheck, zContext, "Child page depth differs");
-      }
-      depth = d2;
-    }
-  }
-  if( !pPage->leaf ){
-    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
-    sqlite3_snprintf(sizeof(zContext), zContext, 
-                     "On page %d at right child: ", iPage);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pBt->autoVacuum ){
-      checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, 0);
-    }
-#endif
-    checkTreePage(pCheck, pgno, pPage, zContext);
-  }
- 
-  /* Check for complete coverage of the page
-  */
-  data = pPage->aData;
-  hdr = pPage->hdrOffset;
-  hit = sqlite3MallocZero( usableSize );
-  if( hit ){
-    memset(hit, 1, get2byte(&data[hdr+5]));
-    nCell = get2byte(&data[hdr+3]);
-    cellStart = hdr + 12 - 4*pPage->leaf;
-    for(i=0; i<nCell; i++){
-      int pc = get2byte(&data[cellStart+i*2]);
-      u16 size = cellSizePtr(pPage, &data[pc]);
-      int j;
-      if( (pc+size-1)>=usableSize || pc<0 ){
-        checkAppendMsg(pCheck, 0, 
-            "Corruption detected in cell %d on page %d",i,iPage,0);
-      }else{
-        for(j=pc+size-1; j>=pc; j--) hit[j]++;
-      }
-    }
-    for(cnt=0, i=get2byte(&data[hdr+1]); i>0 && i<usableSize && cnt<10000; 
-           cnt++){
-      int size = get2byte(&data[i+2]);
-      int j;
-      if( (i+size-1)>=usableSize || i<0 ){
-        checkAppendMsg(pCheck, 0,  
-            "Corruption detected in cell %d on page %d",i,iPage,0);
-      }else{
-        for(j=i+size-1; j>=i; j--) hit[j]++;
-      }
-      i = get2byte(&data[i]);
-    }
-    for(i=cnt=0; i<usableSize; i++){
-      if( hit[i]==0 ){
-        cnt++;
-      }else if( hit[i]>1 ){
-        checkAppendMsg(pCheck, 0,
-          "Multiple uses for byte %d of page %d", i, iPage);
-        break;
-      }
-    }
-    if( cnt!=data[hdr+7] ){
-      checkAppendMsg(pCheck, 0, 
-          "Fragmented space is %d byte reported as %d on page %d",
-          cnt, data[hdr+7], iPage);
-    }
-  }
-  sqlite3_free(hit);
-
-  releasePage(pPage);
-  return depth+1;
+static void moveToParent(BtCursor *pCur){
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  assert( pCur->iPage>0 );
+  assert( pCur->apPage[pCur->iPage] );
+  assertParentIndex(
+    pCur->apPage[pCur->iPage-1], 
+    pCur->aiIdx[pCur->iPage-1], 
+    pCur->apPage[pCur->iPage]->pgno
+  );
+  releasePage(pCur->apPage[pCur->iPage]);
+  pCur->iPage--;
+  pCur->info.nSize = 0;
+  pCur->validNKey = 0;
 }
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** This routine does a complete check of the given BTree file.  aRoot[] is
-** an array of pages numbers were each page number is the root page of
-** a table.  nRoot is the number of entries in aRoot.
+** Move the cursor to point to the root page of its b-tree structure.
+**
+** If the table has a virtual root page, then the cursor is moved to point
+** to the virtual root page instead of the actual root page. A table has a
+** virtual root page when the actual root page contains no cells and a 
+** single child page. This can only happen with the table rooted at page 1.
+**
+** If the b-tree structure is empty, the cursor state is set to 
+** CURSOR_INVALID. Otherwise, the cursor is set to point to the first
+** cell located on the root (or virtual root) page and the cursor state
+** is set to CURSOR_VALID.
 **
-** If everything checks out, this routine returns NULL.  If something is
-** amiss, an error message is written into memory obtained from malloc()
-** and a pointer to that error message is returned.  The calling function
-** is responsible for freeing the error message when it is done.
+** If this function returns successfully, it may be assumed that the
+** page-header flags indicate that the [virtual] root-page is the expected 
+** kind of b-tree page (i.e. if when opening the cursor the caller did not
+** specify a KeyInfo structure the flags byte is set to 0x05 or 0x0D,
+** indicating a table b-tree, or if the caller did specify a KeyInfo 
+** structure the flags byte is set to 0x02 or 0x0A, indicating an index
+** b-tree).
 */
-SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(
-  Btree *p,     /* The btree to be checked */
-  int *aRoot,   /* An array of root pages numbers for individual trees */
-  int nRoot,    /* Number of entries in aRoot[] */
-  int mxErr,    /* Stop reporting errors after this many */
-  int *pnErr    /* Write number of errors seen to this variable */
-){
-  int i;
-  int nRef;
-  IntegrityCk sCheck;
+static int moveToRoot(BtCursor *pCur){
+  MemPage *pRoot;
+  int rc = SQLITE_OK;
+  Btree *p = pCur->pBtree;
   BtShared *pBt = p->pBt;
 
-  sqlite3BtreeEnter(p);
-  pBt->db = p->db;
-  nRef = sqlite3PagerRefcount(pBt->pPager);
-  if( lockBtreeWithRetry(p)!=SQLITE_OK ){
-    sqlite3BtreeLeave(p);
-    return sqlite3StrDup("Unable to acquire a read lock on the database");
-  }
-  sCheck.pBt = pBt;
-  sCheck.pPager = pBt->pPager;
-  sCheck.nPage = sqlite3PagerPagecount(sCheck.pPager);
-  sCheck.mxErr = mxErr;
-  sCheck.nErr = 0;
-  *pnErr = 0;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  if( pBt->nTrunc!=0 ){
-    sCheck.nPage = pBt->nTrunc;
-  }
-#endif
-  if( sCheck.nPage==0 ){
-    unlockBtreeIfUnused(pBt);
-    sqlite3BtreeLeave(p);
-    return 0;
-  }
-  sCheck.anRef = sqlite3_malloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
-  if( !sCheck.anRef ){
-    unlockBtreeIfUnused(pBt);
-    *pnErr = 1;
-    sqlite3BtreeLeave(p);
-    return sqlite3MPrintf(p->db, "Unable to malloc %d bytes", 
-        (sCheck.nPage+1)*sizeof(sCheck.anRef[0]));
-  }
-  for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
-  i = PENDING_BYTE_PAGE(pBt);
-  if( i<=sCheck.nPage ){
-    sCheck.anRef[i] = 1;
-  }
-  sCheck.zErrMsg = 0;
-
-  /* Check the integrity of the freelist
-  */
-  checkList(&sCheck, 1, get4byte(&pBt->pPage1->aData[32]),
-            get4byte(&pBt->pPage1->aData[36]), "Main freelist: ");
-
-  /* Check all the tables.
-  */
-  for(i=0; i<nRoot && sCheck.mxErr; i++){
-    if( aRoot[i]==0 ) continue;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( pBt->autoVacuum && aRoot[i]>1 ){
-      checkPtrmap(&sCheck, aRoot[i], PTRMAP_ROOTPAGE, 0, 0);
+  assert( cursorHoldsMutex(pCur) );
+  assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
+  assert( CURSOR_VALID   < CURSOR_REQUIRESEEK );
+  assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );
+  if( pCur->eState>=CURSOR_REQUIRESEEK ){
+    if( pCur->eState==CURSOR_FAULT ){
+      assert( pCur->skipNext!=SQLITE_OK );
+      return pCur->skipNext;
     }
-#endif
-    checkTreePage(&sCheck, aRoot[i], 0, "List of tree roots: ");
+    sqlite3BtreeClearCursor(pCur);
   }
 
-  /* Make sure every page in the file is referenced
-  */
-  for(i=1; i<=sCheck.nPage && sCheck.mxErr; i++){
-#ifdef SQLITE_OMIT_AUTOVACUUM
-    if( sCheck.anRef[i]==0 ){
-      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
+  if( pCur->iPage>=0 ){
+    int i;
+    for(i=1; i<=pCur->iPage; i++){
+      releasePage(pCur->apPage[i]);
     }
-#else
-    /* If the database supports auto-vacuum, make sure no tables contain
-    ** references to pointer-map pages.
-    */
-    if( sCheck.anRef[i]==0 && 
-       (PTRMAP_PAGENO(pBt, i)!=i || !pBt->autoVacuum) ){
-      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
+    pCur->iPage = 0;
+  }else{
+    rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]);
+    if( rc!=SQLITE_OK ){
+      pCur->eState = CURSOR_INVALID;
+      return rc;
     }
-    if( sCheck.anRef[i]!=0 && 
-       (PTRMAP_PAGENO(pBt, i)==i && pBt->autoVacuum) ){
-      checkAppendMsg(&sCheck, 0, "Pointer map page %d is referenced", i);
+    pCur->iPage = 0;
+
+    /* If pCur->pKeyInfo is not NULL, then the caller that opened this cursor
+    ** expected to open it on an index b-tree. Otherwise, if pKeyInfo is
+    ** NULL, the caller expects a table b-tree. If this is not the case,
+    ** return an SQLITE_CORRUPT error.  */
+    assert( pCur->apPage[0]->intKey==1 || pCur->apPage[0]->intKey==0 );
+    if( (pCur->pKeyInfo==0)!=pCur->apPage[0]->intKey ){
+      return SQLITE_CORRUPT_BKPT;
     }
-#endif
   }
 
-  /* Make sure this analysis did not leave any unref() pages
-  */
-  unlockBtreeIfUnused(pBt);
-  if( nRef != sqlite3PagerRefcount(pBt->pPager) ){
-    checkAppendMsg(&sCheck, 0, 
-      "Outstanding page count goes from %d to %d during this analysis",
-      nRef, sqlite3PagerRefcount(pBt->pPager)
-    );
-  }
+  /* Assert that the root page is of the correct type. This must be the
+  ** case as the call to this function that loaded the root-page (either
+  ** this call or a previous invocation) would have detected corruption 
+  ** if the assumption were not true, and it is not possible for the flags 
+  ** byte to have been modified while this cursor is holding a reference
+  ** to the page.  */
+  pRoot = pCur->apPage[0];
+  assert( pRoot->pgno==pCur->pgnoRoot );
+  assert( pRoot->isInit && (pCur->pKeyInfo==0)==pRoot->intKey );
 
-  /* Clean  up and report errors.
-  */
-  sqlite3BtreeLeave(p);
-  sqlite3_free(sCheck.anRef);
-  *pnErr = sCheck.nErr;
-  return sCheck.zErrMsg;
-}
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
+  pCur->aiIdx[0] = 0;
+  pCur->info.nSize = 0;
+  pCur->atLast = 0;
+  pCur->validNKey = 0;
 
-/*
-** Return the full pathname of the underlying database file.
-**
-** The pager filename is invariant as long as the pager is
-** open so it is safe to access without the BtShared mutex.
-*/
-SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *p){
-  assert( p->pBt->pPager!=0 );
-  return sqlite3PagerFilename(p->pBt->pPager);
+  if( pRoot->nCell==0 && !pRoot->leaf ){
+    Pgno subpage;
+    if( pRoot->pgno!=1 ) return SQLITE_CORRUPT_BKPT;
+    subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
+    pCur->eState = CURSOR_VALID;
+    rc = moveToChild(pCur, subpage);
+  }else{
+    pCur->eState = ((pRoot->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
+  }
+  return rc;
 }
 
 /*
-** Return the pathname of the directory that contains the database file.
+** Move the cursor down to the left-most leaf entry beneath the
+** entry to which it is currently pointing.
 **
-** The pager directory name is invariant as long as the pager is
-** open so it is safe to access without the BtShared mutex.
+** The left-most leaf is the one with the smallest key - the first
+** in ascending order.
 */
-SQLITE_PRIVATE const char *sqlite3BtreeGetDirname(Btree *p){
-  assert( p->pBt->pPager!=0 );
-  return sqlite3PagerDirname(p->pBt->pPager);
-}
+static int moveToLeftmost(BtCursor *pCur){
+  Pgno pgno;
+  int rc = SQLITE_OK;
+  MemPage *pPage;
 
-/*
-** Return the pathname of the journal file for this database. The return
-** value of this routine is the same regardless of whether the journal file
-** has been created or not.
-**
-** The pager journal filename is invariant as long as the pager is
-** open so it is safe to access without the BtShared mutex.
-*/
-SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *p){
-  assert( p->pBt->pPager!=0 );
-  return sqlite3PagerJournalname(p->pBt->pPager);
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  while( rc==SQLITE_OK && !(pPage = pCur->apPage[pCur->iPage])->leaf ){
+    assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
+    pgno = get4byte(findCell(pPage, pCur->aiIdx[pCur->iPage]));
+    rc = moveToChild(pCur, pgno);
+  }
+  return rc;
 }
 
-#ifndef SQLITE_OMIT_VACUUM
 /*
-** Copy the complete content of pBtFrom into pBtTo.  A transaction
-** must be active for both files.
-**
-** The size of file pTo may be reduced by this operation.
-** If anything goes wrong, the transaction on pTo is rolled back. 
+** Move the cursor down to the right-most leaf entry beneath the
+** page to which it is currently pointing.  Notice the difference
+** between moveToLeftmost() and moveToRightmost().  moveToLeftmost()
+** finds the left-most entry beneath the *entry* whereas moveToRightmost()
+** finds the right-most entry beneath the *page*.
 **
-** If successful, CommitPhaseOne() may be called on pTo before returning. 
-** The caller should finish committing the transaction on pTo by calling
-** sqlite3BtreeCommit().
+** The right-most entry is the one with the largest key - the last
+** key in ascending order.
 */
-static int btreeCopyFile(Btree *pTo, Btree *pFrom){
+static int moveToRightmost(BtCursor *pCur){
+  Pgno pgno;
   int rc = SQLITE_OK;
-  Pgno i;
-
-  Pgno nFromPage;     /* Number of pages in pFrom */
-  Pgno nToPage;       /* Number of pages in pTo */
-  Pgno nNewPage;      /* Number of pages in pTo after the copy */
-
-  Pgno iSkip;         /* Pending byte page in pTo */
-  int nToPageSize;    /* Page size of pTo in bytes */
-  int nFromPageSize;  /* Page size of pFrom in bytes */
-
-  BtShared *pBtTo = pTo->pBt;
-  BtShared *pBtFrom = pFrom->pBt;
-  pBtTo->db = pTo->db;
-  pBtFrom->db = pFrom->db;
-
-  nToPageSize = pBtTo->pageSize;
-  nFromPageSize = pBtFrom->pageSize;
+  MemPage *pPage = 0;
 
-  if( pTo->inTrans!=TRANS_WRITE || pFrom->inTrans!=TRANS_WRITE ){
-    return SQLITE_ERROR;
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  while( rc==SQLITE_OK && !(pPage = pCur->apPage[pCur->iPage])->leaf ){
+    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+    pCur->aiIdx[pCur->iPage] = pPage->nCell;
+    rc = moveToChild(pCur, pgno);
   }
-  if( pBtTo->pCursor ){
-    return SQLITE_BUSY;
+  if( rc==SQLITE_OK ){
+    pCur->aiIdx[pCur->iPage] = pPage->nCell-1;
+    pCur->info.nSize = 0;
+    pCur->validNKey = 0;
   }
+  return rc;
+}
 
-  nToPage = sqlite3PagerPagecount(pBtTo->pPager);
-  nFromPage = sqlite3PagerPagecount(pBtFrom->pPager);
-  iSkip = PENDING_BYTE_PAGE(pBtTo);
-
-  /* Variable nNewPage is the number of pages required to store the
-  ** contents of pFrom using the current page-size of pTo.
-  */
-  nNewPage = ((i64)nFromPage * (i64)nFromPageSize + (i64)nToPageSize - 1) / 
-      (i64)nToPageSize;
-
-  for(i=1; rc==SQLITE_OK && (i<=nToPage || i<=nNewPage); i++){
+/* Move the cursor to the first entry in the table.  Return SQLITE_OK
+** on success.  Set *pRes to 0 if the cursor actually points to something
+** or set *pRes to 1 if the table is empty.
+*/
+SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
+  int rc;
 
-    /* Journal the original page.
-    **
-    ** iSkip is the page number of the locking page (PENDING_BYTE_PAGE)
-    ** in database *pTo (before the copy). This page is never written 
-    ** into the journal file. Unless i==iSkip or the page was not
-    ** present in pTo before the copy operation, journal page i from pTo.
-    */
-    if( i!=iSkip && i<=nToPage ){
-      DbPage *pDbPage = 0;
-      rc = sqlite3PagerGet(pBtTo->pPager, i, &pDbPage);
-      if( rc==SQLITE_OK ){
-        rc = sqlite3PagerWrite(pDbPage);
-        if( rc==SQLITE_OK && i>nFromPage ){
-          /* Yeah.  It seems wierd to call DontWrite() right after Write(). But
-          ** that is because the names of those procedures do not exactly 
-          ** represent what they do.  Write() really means "put this page in the
-          ** rollback journal and mark it as dirty so that it will be written
-          ** to the database file later."  DontWrite() undoes the second part of
-          ** that and prevents the page from being written to the database. The
-          ** page is still on the rollback journal, though.  And that is the 
-          ** whole point of this block: to put pages on the rollback journal. 
-          */
-          sqlite3PagerDontWrite(pDbPage);
-        }
-        sqlite3PagerUnref(pDbPage);
-      }
+  assert( cursorHoldsMutex(pCur) );
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  rc = moveToRoot(pCur);
+  if( rc==SQLITE_OK ){
+    if( pCur->eState==CURSOR_INVALID ){
+      assert( pCur->apPage[pCur->iPage]->nCell==0 );
+      *pRes = 1;
+      rc = SQLITE_OK;
+    }else{
+      assert( pCur->apPage[pCur->iPage]->nCell>0 );
+      *pRes = 0;
+      rc = moveToLeftmost(pCur);
     }
+  }
+  return rc;
+}
 
-    /* Overwrite the data in page i of the target database */
-    if( rc==SQLITE_OK && i!=iSkip && i<=nNewPage ){
-
-      DbPage *pToPage = 0;
-      sqlite3_int64 iOff;
-
-      rc = sqlite3PagerGet(pBtTo->pPager, i, &pToPage);
-      if( rc==SQLITE_OK ){
-        rc = sqlite3PagerWrite(pToPage);
-      }
-
-      for(
-        iOff=(i-1)*nToPageSize; 
-        rc==SQLITE_OK && iOff<i*nToPageSize; 
-        iOff += nFromPageSize
-      ){
-        DbPage *pFromPage = 0;
-        Pgno iFrom = (iOff/nFromPageSize)+1;
-
-        if( iFrom==PENDING_BYTE_PAGE(pBtFrom) ){
-          continue;
-        }
-
-        rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
-        if( rc==SQLITE_OK ){
-          char *zTo = sqlite3PagerGetData(pToPage);
-          char *zFrom = sqlite3PagerGetData(pFromPage);
-          int nCopy;
-
-          if( nFromPageSize>=nToPageSize ){
-            zFrom += ((i-1)*nToPageSize - ((iFrom-1)*nFromPageSize));
-            nCopy = nToPageSize;
-          }else{
-            zTo += (((iFrom-1)*nFromPageSize) - (i-1)*nToPageSize);
-            nCopy = nFromPageSize;
-          }
-
-          memcpy(zTo, zFrom, nCopy);
-	  sqlite3PagerUnref(pFromPage);
-        }
-      }
+/* Move the cursor to the last entry in the table.  Return SQLITE_OK
+** on success.  Set *pRes to 0 if the cursor actually points to something
+** or set *pRes to 1 if the table is empty.
+*/
+SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
+  int rc;
+ 
+  assert( cursorHoldsMutex(pCur) );
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
 
-      if( pToPage ) sqlite3PagerUnref(pToPage);
+  /* If the cursor already points to the last entry, this is a no-op. */
+  if( CURSOR_VALID==pCur->eState && pCur->atLast ){
+#ifdef SQLITE_DEBUG
+    /* This block serves to assert() that the cursor really does point 
+    ** to the last entry in the b-tree. */
+    int ii;
+    for(ii=0; ii<pCur->iPage; ii++){
+      assert( pCur->aiIdx[ii]==pCur->apPage[ii]->nCell );
     }
+    assert( pCur->aiIdx[pCur->iPage]==pCur->apPage[pCur->iPage]->nCell-1 );
+    assert( pCur->apPage[pCur->iPage]->leaf );
+#endif
+    return SQLITE_OK;
   }
 
-  /* If things have worked so far, the database file may need to be 
-  ** truncated. The complex part is that it may need to be truncated to
-  ** a size that is not an integer multiple of nToPageSize - the current
-  ** page size used by the pager associated with B-Tree pTo.
-  **
-  ** For example, say the page-size of pTo is 2048 bytes and the original 
-  ** number of pages is 5 (10 KB file). If pFrom has a page size of 1024 
-  ** bytes and 9 pages, then the file needs to be truncated to 9KB.
-  */
+  rc = moveToRoot(pCur);
   if( rc==SQLITE_OK ){
-    if( nFromPageSize!=nToPageSize ){
-      sqlite3_file *pFile = sqlite3PagerFile(pBtTo->pPager);
-      i64 iSize = (i64)nFromPageSize * (i64)nFromPage;
-      i64 iNow = (i64)((nToPage>nNewPage)?nToPage:nNewPage) * (i64)nToPageSize; 
-      i64 iPending = ((i64)PENDING_BYTE_PAGE(pBtTo)-1) *(i64)nToPageSize;
-  
-      assert( iSize<=iNow );
-  
-      /* Commit phase one syncs the journal file associated with pTo 
-      ** containing the original data. It does not sync the database file
-      ** itself. After doing this it is safe to use OsTruncate() and other
-      ** file APIs on the database file directly.
-      */
-      pBtTo->db = pTo->db;
-      rc = sqlite3PagerCommitPhaseOne(pBtTo->pPager, 0, 0, 1);
-      if( iSize<iNow && rc==SQLITE_OK ){
-        rc = sqlite3OsTruncate(pFile, iSize);
-      }
-  
-      /* The loop that copied data from database pFrom to pTo did not
-      ** populate the locking page of database pTo. If the page-size of
-      ** pFrom is smaller than that of pTo, this means some data will
-      ** not have been copied. 
-      **
-      ** This block copies the missing data from database pFrom to pTo 
-      ** using file APIs. This is safe because at this point we know that
-      ** all of the original data from pTo has been synced into the 
-      ** journal file. At this point it would be safe to do anything at
-      ** all to the database file except truncate it to zero bytes.
-      */
-      if( rc==SQLITE_OK && nFromPageSize<nToPageSize && iSize>iPending){
-        i64 iOff;
-        for(
-          iOff=iPending; 
-          rc==SQLITE_OK && iOff<(iPending+nToPageSize); 
-          iOff += nFromPageSize
-        ){
-          DbPage *pFromPage = 0;
-          Pgno iFrom = (iOff/nFromPageSize)+1;
-  
-          if( iFrom==PENDING_BYTE_PAGE(pBtFrom) || iFrom>nFromPage ){
-            continue;
-          }
-  
-          rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
-          if( rc==SQLITE_OK ){
-            char *zFrom = sqlite3PagerGetData(pFromPage);
-  	  rc = sqlite3OsWrite(pFile, zFrom, nFromPageSize, iOff);
-            sqlite3PagerUnref(pFromPage);
-          }
-        }
-      }
-  
-      /* Sync the database file */
-      if( rc==SQLITE_OK ){
-        rc = sqlite3PagerSync(pBtTo->pPager);
-      }
+    if( CURSOR_INVALID==pCur->eState ){
+      assert( pCur->apPage[pCur->iPage]->nCell==0 );
+      *pRes = 1;
     }else{
-      rc = sqlite3PagerTruncate(pBtTo->pPager, nNewPage);
-    }
-    if( rc==SQLITE_OK ){
-      pBtTo->pageSizeFixed = 0;
+      assert( pCur->eState==CURSOR_VALID );
+      *pRes = 0;
+      rc = moveToRightmost(pCur);
+      pCur->atLast = rc==SQLITE_OK ?1:0;
     }
   }
-
-  if( rc ){
-    sqlite3BtreeRollback(pTo);
-  }
-
-  return rc;  
-}
-SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
-  int rc;
-  sqlite3BtreeEnter(pTo);
-  sqlite3BtreeEnter(pFrom);
-  rc = btreeCopyFile(pTo, pFrom);
-  sqlite3BtreeLeave(pFrom);
-  sqlite3BtreeLeave(pTo);
   return rc;
 }
 
-#endif /* SQLITE_OMIT_VACUUM */
-
-/*
-** Return non-zero if a transaction is active.
+/* Move the cursor so that it points to an entry near the key 
+** specified by pIdxKey or intKey.   Return a success code.
+**
+** For INTKEY tables, the intKey parameter is used.  pIdxKey 
+** must be NULL.  For index tables, pIdxKey is used and intKey
+** is ignored.
+**
+** If an exact match is not found, then the cursor is always
+** left pointing at a leaf page which would hold the entry if it
+** were present.  The cursor might point to an entry that comes
+** before or after the key.
+**
+** An integer is written into *pRes which is the result of
+** comparing the key with the entry to which the cursor is 
+** pointing.  The meaning of the integer written into
+** *pRes is as follows:
+**
+**     *pRes<0      The cursor is left pointing at an entry that
+**                  is smaller than intKey/pIdxKey or if the table is empty
+**                  and the cursor is therefore left point to nothing.
+**
+**     *pRes==0     The cursor is left pointing at an entry that
+**                  exactly matches intKey/pIdxKey.
+**
+**     *pRes>0      The cursor is left pointing at an entry that
+**                  is larger than intKey/pIdxKey.
+**
 */
-SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree *p){
-  assert( p==0 || sqlite3_mutex_held(p->db->mutex) );
-  return (p && (p->inTrans==TRANS_WRITE));
-}
-
-/*
-** Return non-zero if a statement transaction is active.
-*/
-SQLITE_PRIVATE int sqlite3BtreeIsInStmt(Btree *p){
-  assert( sqlite3BtreeHoldsMutex(p) );
-  return (p->pBt && p->pBt->inStmt);
-}
-
-/*
-** Return non-zero if a read (or write) transaction is active.
-*/
-SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree *p){
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  return (p && (p->inTrans!=TRANS_NONE));
-}
-
-/*
-** This function returns a pointer to a blob of memory associated with
-** a single shared-btree. The memory is used by client code for its own
-** purposes (for example, to store a high-level schema associated with 
-** the shared-btree). The btree layer manages reference counting issues.
-**
-** The first time this is called on a shared-btree, nBytes bytes of memory
-** are allocated, zeroed, and returned to the caller. For each subsequent 
-** call the nBytes parameter is ignored and a pointer to the same blob
-** of memory returned. 
-**
-** Just before the shared-btree is closed, the function passed as the 
-** xFree argument when the memory allocation was made is invoked on the 
-** blob of allocated memory. This function should not call sqlite3_free()
-** on the memory, the btree layer does that.
-*/
-SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
-  BtShared *pBt = p->pBt;
-  sqlite3BtreeEnter(p);
-  if( !pBt->pSchema ){
-    pBt->pSchema = sqlite3MallocZero(nBytes);
-    pBt->xFreeSchema = xFree;
-  }
-  sqlite3BtreeLeave(p);
-  return pBt->pSchema;
-}
-
-/*
-** Return true if another user of the same shared btree as the argument
-** handle holds an exclusive lock on the sqlite_master table.
-*/
-SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *p){
-  int rc;
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  sqlite3BtreeEnter(p);
-  rc = (queryTableLock(p, MASTER_ROOT, READ_LOCK)!=SQLITE_OK);
-  sqlite3BtreeLeave(p);
-  return rc;
-}
+SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
+  BtCursor *pCur,          /* The cursor to be moved */
+  UnpackedRecord *pIdxKey, /* Unpacked index key */
+  i64 intKey,              /* The table key */
+  int biasRight,           /* If true, bias the search to the high end */
+  int *pRes                /* Write search results here */
+){
+  int rc;
 
+  assert( cursorHoldsMutex(pCur) );
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  assert( pRes );
+  assert( (pIdxKey==0)==(pCur->pKeyInfo==0) );
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
-/*
-** Obtain a lock on the table whose root page is iTab.  The
-** lock is a write lock if isWritelock is true or a read lock
-** if it is false.
-*/
-SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
-  int rc = SQLITE_OK;
-  if( p->sharable ){
-    u8 lockType = READ_LOCK + isWriteLock;
-    assert( READ_LOCK+1==WRITE_LOCK );
-    assert( isWriteLock==0 || isWriteLock==1 );
-    sqlite3BtreeEnter(p);
-    rc = queryTableLock(p, iTab, lockType);
-    if( rc==SQLITE_OK ){
-      rc = lockTable(p, iTab, lockType);
+  /* If the cursor is already positioned at the point we are trying
+  ** to move to, then just return without doing any work */
+  if( pCur->eState==CURSOR_VALID && pCur->validNKey 
+   && pCur->apPage[0]->intKey 
+  ){
+    if( pCur->info.nKey==intKey ){
+      *pRes = 0;
+      return SQLITE_OK;
     }
-    sqlite3BtreeLeave(p);
-  }
-  return rc;
-}
-#endif
-
-#ifndef SQLITE_OMIT_INCRBLOB
-/*
-** Argument pCsr must be a cursor opened for writing on an 
-** INTKEY table currently pointing at a valid table entry. 
-** This function modifies the data stored as part of that entry.
-** Only the data content may only be modified, it is not possible
-** to change the length of the data stored.
-*/
-SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
-  assert( cursorHoldsMutex(pCsr) );
-  assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
-  assert(pCsr->isIncrblobHandle);
-  if( pCsr->eState>=CURSOR_REQUIRESEEK ){
-    if( pCsr->eState==CURSOR_FAULT ){
-      return pCsr->skip;
-    }else{
-      return SQLITE_ABORT;
+    if( pCur->atLast && pCur->info.nKey<intKey ){
+      *pRes = -1;
+      return SQLITE_OK;
     }
   }
 
-  /* Check some preconditions: 
-  **   (a) the cursor is open for writing,
-  **   (b) there is no read-lock on the table being modified and
-  **   (c) the cursor points at a valid row of an intKey table.
-  */
-  if( !pCsr->wrFlag ){
-    return SQLITE_READONLY;
-  }
-  assert( !pCsr->pBt->readOnly 
-          && pCsr->pBt->inTransaction==TRANS_WRITE );
-  if( checkReadLocks(pCsr->pBtree, pCsr->pgnoRoot, pCsr) ){
-    return SQLITE_LOCKED; /* The table pCur points to has a read lock */
+  rc = moveToRoot(pCur);
+  if( rc ){
+    return rc;
   }
-  if( pCsr->eState==CURSOR_INVALID || !pCsr->pPage->intKey ){
-    return SQLITE_ERROR;
+  assert( pCur->apPage[pCur->iPage] );
+  assert( pCur->apPage[pCur->iPage]->isInit );
+  assert( pCur->apPage[pCur->iPage]->nCell>0 || pCur->eState==CURSOR_INVALID );
+  if( pCur->eState==CURSOR_INVALID ){
+    *pRes = -1;
+    assert( pCur->apPage[pCur->iPage]->nCell==0 );
+    return SQLITE_OK;
   }
+  assert( pCur->apPage[0]->intKey || pIdxKey );
+  for(;;){
+    int lwr, upr;
+    Pgno chldPg;
+    MemPage *pPage = pCur->apPage[pCur->iPage];
+    int c;
+
+    /* pPage->nCell must be greater than zero. If this is the root-page
+    ** the cursor would have been INVALID above and this for(;;) loop
+    ** not run. If this is not the root-page, then the moveToChild() routine
+    ** would have already detected db corruption. Similarly, pPage must
+    ** be the right kind (index or table) of b-tree page. Otherwise
+    ** a moveToChild() or moveToRoot() call would have detected corruption.  */
+    assert( pPage->nCell>0 );
+    assert( pPage->intKey==(pIdxKey==0) );
+    lwr = 0;
+    upr = pPage->nCell-1;
+    if( biasRight ){
+      pCur->aiIdx[pCur->iPage] = (u16)upr;
+    }else{
+      pCur->aiIdx[pCur->iPage] = (u16)((upr+lwr)/2);
+    }
+    for(;;){
+      int idx = pCur->aiIdx[pCur->iPage]; /* Index of current cell in pPage */
+      u8 *pCell;                          /* Pointer to current cell in pPage */
 
-  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 0, 1);
+      pCur->info.nSize = 0;
+      pCell = findCell(pPage, idx) + pPage->childPtrSize;
+      if( pPage->intKey ){
+        i64 nCellKey;
+        if( pPage->hasData ){
+          u32 dummy;
+          pCell += getVarint32(pCell, dummy);
+        }
+        getVarint(pCell, (u64*)&nCellKey);
+        if( nCellKey==intKey ){
+          c = 0;
+        }else if( nCellKey<intKey ){
+          c = -1;
+        }else{
+          assert( nCellKey>intKey );
+          c = +1;
+        }
+        pCur->validNKey = 1;
+        pCur->info.nKey = nCellKey;
+      }else{
+        /* The maximum supported page-size is 32768 bytes. This means that
+        ** the maximum number of record bytes stored on an index B-Tree
+        ** page is at most 8198 bytes, which may be stored as a 2-byte
+        ** varint. This information is used to attempt to avoid parsing 
+        ** the entire cell by checking for the cases where the record is 
+        ** stored entirely within the b-tree page by inspecting the first 
+        ** 2 bytes of the cell.
+        */
+        int nCell = pCell[0];
+        if( !(nCell & 0x80) && nCell<=pPage->maxLocal ){
+          /* This branch runs if the record-size field of the cell is a
+          ** single byte varint and the record fits entirely on the main
+          ** b-tree page.  */
+          c = sqlite3VdbeRecordCompare(nCell, (void*)&pCell[1], pIdxKey);
+        }else if( !(pCell[1] & 0x80) 
+          && (nCell = ((nCell&0x7f)<<7) + pCell[1])<=pPage->maxLocal
+        ){
+          /* The record-size field is a 2 byte varint and the record 
+          ** fits entirely on the main b-tree page.  */
+          c = sqlite3VdbeRecordCompare(nCell, (void*)&pCell[2], pIdxKey);
+        }else{
+          /* The record flows over onto one or more overflow pages. In
+          ** this case the whole cell needs to be parsed, a buffer allocated
+          ** and accessPayload() used to retrieve the record into the
+          ** buffer before VdbeRecordCompare() can be called. */
+          void *pCellKey;
+          u8 * const pCellBody = pCell - pPage->childPtrSize;
+          btreeParseCellPtr(pPage, pCellBody, &pCur->info);
+          nCell = (int)pCur->info.nKey;
+          pCellKey = sqlite3Malloc( nCell );
+          if( pCellKey==0 ){
+            rc = SQLITE_NOMEM;
+            goto moveto_finish;
+          }
+          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
+          if( rc ){
+            sqlite3_free(pCellKey);
+            goto moveto_finish;
+          }
+          c = sqlite3VdbeRecordCompare(nCell, pCellKey, pIdxKey);
+          sqlite3_free(pCellKey);
+        }
+      }
+      if( c==0 ){
+        if( pPage->intKey && !pPage->leaf ){
+          lwr = idx;
+          upr = lwr - 1;
+          break;
+        }else{
+          *pRes = 0;
+          rc = SQLITE_OK;
+          goto moveto_finish;
+        }
+      }
+      if( c<0 ){
+        lwr = idx+1;
+      }else{
+        upr = idx-1;
+      }
+      if( lwr>upr ){
+        break;
+      }
+      pCur->aiIdx[pCur->iPage] = (u16)((lwr+upr)/2);
+    }
+    assert( lwr==upr+1 );
+    assert( pPage->isInit );
+    if( pPage->leaf ){
+      chldPg = 0;
+    }else if( lwr>=pPage->nCell ){
+      chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+    }else{
+      chldPg = get4byte(findCell(pPage, lwr));
+    }
+    if( chldPg==0 ){
+      assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+      *pRes = c;
+      rc = SQLITE_OK;
+      goto moveto_finish;
+    }
+    pCur->aiIdx[pCur->iPage] = (u16)lwr;
+    pCur->info.nSize = 0;
+    pCur->validNKey = 0;
+    rc = moveToChild(pCur, chldPg);
+    if( rc ) goto moveto_finish;
+  }
+moveto_finish:
+  return rc;
 }
 
-/* 
-** Set a flag on this cursor to cache the locations of pages from the 
-** overflow list for the current row. This is used by cursors opened
-** for incremental blob IO only.
-**
-** This function sets a flag only. The actual page location cache
-** (stored in BtCursor.aOverflow[]) is allocated and used by function
-** accessPayload() (the worker function for sqlite3BtreeData() and
-** sqlite3BtreePutData()).
-*/
-SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *pCur){
-  assert( cursorHoldsMutex(pCur) );
-  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
-  assert(!pCur->isIncrblobHandle);
-  assert(!pCur->aOverflow);
-  pCur->isIncrblobHandle = 1;
-}
-#endif
 
-/************** End of btree.c ***********************************************/
-/************** Begin file vdbefifo.c ****************************************/
 /*
-** 2005 June 16
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Return TRUE if the cursor is not pointing at an entry of the table.
 **
-*************************************************************************
-** This file implements a FIFO queue of rowids used for processing
-** UPDATE and DELETE statements.
+** TRUE will be returned after a call to sqlite3BtreeNext() moves
+** past the last entry in the table or sqlite3BtreePrev() moves past
+** the first entry.  TRUE is also returned if the table is empty.
 */
+SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor *pCur){
+  /* TODO: What if the cursor is in CURSOR_REQUIRESEEK but all table entries
+  ** have been deleted? This API will need to change to return an error code
+  ** as well as the boolean result value.
+  */
+  return (CURSOR_VALID!=pCur->eState);
+}
 
 /*
-** Constants FIFOSIZE_FIRST and FIFOSIZE_MAX are the initial
-** number of entries in a fifo page and the maximum number of
-** entries in a fifo page.
+** Advance the cursor to the next entry in the database.  If
+** successful then set *pRes=0.  If the cursor
+** was already pointing to the last entry in the database before
+** this routine was called, then set *pRes=1.
 */
-#define FIFOSIZE_FIRST (((128-sizeof(FifoPage))/8)+1)
-#ifdef SQLITE_MALLOC_SOFT_LIMIT
-# define FIFOSIZE_MAX   (((SQLITE_MALLOC_SOFT_LIMIT-sizeof(FifoPage))/8)+1)
-#else
-# define FIFOSIZE_MAX   (((262144-sizeof(FifoPage))/8)+1)
-#endif
+SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
+  int rc;
+  int idx;
+  MemPage *pPage;
 
-/*
-** Allocate a new FifoPage and return a pointer to it.  Return NULL if
-** we run out of memory.  Leave space on the page for nEntry entries.
-*/
-static FifoPage *allocateFifoPage(int nEntry){
-  FifoPage *pPage;
-  if( nEntry>FIFOSIZE_MAX ){
-    nEntry = FIFOSIZE_MAX;
+  assert( cursorHoldsMutex(pCur) );
+  rc = restoreCursorPosition(pCur);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
-  pPage = sqlite3_malloc( sizeof(FifoPage) + sizeof(i64)*(nEntry-1) );
-  if( pPage ){
-    pPage->nSlot = nEntry;
-    pPage->iWrite = 0;
-    pPage->iRead = 0;
-    pPage->pNext = 0;
+  assert( pRes!=0 );
+  if( CURSOR_INVALID==pCur->eState ){
+    *pRes = 1;
+    return SQLITE_OK;
   }
-  return pPage;
-}
+  if( pCur->skipNext>0 ){
+    pCur->skipNext = 0;
+    *pRes = 0;
+    return SQLITE_OK;
+  }
+  pCur->skipNext = 0;
 
-/*
-** Initialize a Fifo structure.
-*/
-SQLITE_PRIVATE void sqlite3VdbeFifoInit(Fifo *pFifo){
-  memset(pFifo, 0, sizeof(*pFifo));
-}
+  pPage = pCur->apPage[pCur->iPage];
+  idx = ++pCur->aiIdx[pCur->iPage];
+  assert( pPage->isInit );
+  assert( idx<=pPage->nCell );
 
-/*
-** Push a single 64-bit integer value into the Fifo.  Return SQLITE_OK
-** normally.   SQLITE_NOMEM is returned if we are unable to allocate
-** memory.
-*/
-SQLITE_PRIVATE int sqlite3VdbeFifoPush(Fifo *pFifo, i64 val){
-  FifoPage *pPage;
-  pPage = pFifo->pLast;
-  if( pPage==0 ){
-    pPage = pFifo->pLast = pFifo->pFirst = allocateFifoPage(FIFOSIZE_FIRST);
-    if( pPage==0 ){
-      return SQLITE_NOMEM;
-    }
-  }else if( pPage->iWrite>=pPage->nSlot ){
-    pPage->pNext = allocateFifoPage(pFifo->nEntry);
-    if( pPage->pNext==0 ){
-      return SQLITE_NOMEM;
+  pCur->info.nSize = 0;
+  pCur->validNKey = 0;
+  if( idx>=pPage->nCell ){
+    if( !pPage->leaf ){
+      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
+      if( rc ) return rc;
+      rc = moveToLeftmost(pCur);
+      *pRes = 0;
+      return rc;
     }
-    pPage = pFifo->pLast = pPage->pNext;
-  }
-  pPage->aSlot[pPage->iWrite++] = val;
-  pFifo->nEntry++;
-  return SQLITE_OK;
-}
-
-/*
-** Extract a single 64-bit integer value from the Fifo.  The integer
-** extracted is the one least recently inserted.  If the Fifo is empty
-** return SQLITE_DONE.
-*/
-SQLITE_PRIVATE int sqlite3VdbeFifoPop(Fifo *pFifo, i64 *pVal){
-  FifoPage *pPage;
-  if( pFifo->nEntry==0 ){
-    return SQLITE_DONE;
-  }
-  assert( pFifo->nEntry>0 );
-  pPage = pFifo->pFirst;
-  assert( pPage!=0 );
-  assert( pPage->iWrite>pPage->iRead );
-  assert( pPage->iWrite<=pPage->nSlot );
-  assert( pPage->iRead<pPage->nSlot );
-  assert( pPage->iRead>=0 );
-  *pVal = pPage->aSlot[pPage->iRead++];
-  pFifo->nEntry--;
-  if( pPage->iRead>=pPage->iWrite ){
-    pFifo->pFirst = pPage->pNext;
-    sqlite3_free(pPage);
-    if( pFifo->nEntry==0 ){
-      assert( pFifo->pLast==pPage );
-      pFifo->pLast = 0;
+    do{
+      if( pCur->iPage==0 ){
+        *pRes = 1;
+        pCur->eState = CURSOR_INVALID;
+        return SQLITE_OK;
+      }
+      moveToParent(pCur);
+      pPage = pCur->apPage[pCur->iPage];
+    }while( pCur->aiIdx[pCur->iPage]>=pPage->nCell );
+    *pRes = 0;
+    if( pPage->intKey ){
+      rc = sqlite3BtreeNext(pCur, pRes);
     }else{
-      assert( pFifo->pFirst!=0 );
+      rc = SQLITE_OK;
     }
-  }else{
-    assert( pFifo->nEntry>0 );
-  }
-  return SQLITE_OK;
-}
-
-/*
-** Delete all information from a Fifo object.   Free all memory held
-** by the Fifo.
-*/
-SQLITE_PRIVATE void sqlite3VdbeFifoClear(Fifo *pFifo){
-  FifoPage *pPage, *pNextPage;
-  for(pPage=pFifo->pFirst; pPage; pPage=pNextPage){
-    pNextPage = pPage->pNext;
-    sqlite3_free(pPage);
+    return rc;
   }
-  sqlite3VdbeFifoInit(pFifo);
-}
-
-/************** End of vdbefifo.c ********************************************/
-/************** Begin file vdbemem.c *****************************************/
-/*
-** 2004 May 26
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-**
-** This file contains code use to manipulate "Mem" structure.  A "Mem"
-** stores a single value in the VDBE.  Mem is an opaque structure visible
-** only within the VDBE.  Interface routines refer to a Mem using the
-** name sqlite_value
-*/
-
-/*
-** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
-** P if required.
-*/
-#define expandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
-
-/*
-** If pMem is an object with a valid string representation, this routine
-** ensures the internal encoding for the string representation is
-** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
-**
-** If pMem is not a string object, or the encoding of the string
-** representation is already stored using the requested encoding, then this
-** routine is a no-op.
-**
-** SQLITE_OK is returned if the conversion is successful (or not required).
-** SQLITE_NOMEM may be returned if a malloc() fails during conversion
-** between formats.
-*/
-SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *pMem, int desiredEnc){
-  int rc;
-  if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){
+  *pRes = 0;
+  if( pPage->leaf ){
     return SQLITE_OK;
   }
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-#ifdef SQLITE_OMIT_UTF16
-  return SQLITE_ERROR;
-#else
-
-  /* MemTranslate() may return SQLITE_OK or SQLITE_NOMEM. If NOMEM is returned,
-  ** then the encoding of the value may not have changed.
-  */
-  rc = sqlite3VdbeMemTranslate(pMem, desiredEnc);
-  assert(rc==SQLITE_OK    || rc==SQLITE_NOMEM);
-  assert(rc==SQLITE_OK    || pMem->enc!=desiredEnc);
-  assert(rc==SQLITE_NOMEM || pMem->enc==desiredEnc);
+  rc = moveToLeftmost(pCur);
   return rc;
-#endif
 }
 
+
 /*
-** Make sure pMem->z points to a writable allocation of at least 
-** n bytes.
-**
-** If the memory cell currently contains string or blob data
-** and the third argument passed to this function is true, the 
-** current content of the cell is preserved. Otherwise, it may
-** be discarded.  
-**
-** This function sets the MEM_Dyn flag and clears any xDel callback.
-** It also clears MEM_Ephem and MEM_Static. If the preserve flag is 
-** not set, Mem.n is zeroed.
+** Step the cursor to the back to the previous entry in the database.  If
+** successful then set *pRes=0.  If the cursor
+** was already pointing to the first entry in the database before
+** this routine was called, then set *pRes=1.
 */
-SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve){
-  assert( 1 >=
-    ((pMem->zMalloc && pMem->zMalloc==pMem->z) ? 1 : 0) +
-    (((pMem->flags&MEM_Dyn)&&pMem->xDel) ? 1 : 0) + 
-    ((pMem->flags&MEM_Ephem) ? 1 : 0) + 
-    ((pMem->flags&MEM_Static) ? 1 : 0)
-  );
-
-  if( !pMem->zMalloc || sqlite3MallocSize(pMem->zMalloc)<n ){
-    n = (n>32?n:32);
-    if( preserve && pMem->z==pMem->zMalloc ){
-      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
-      if( !pMem->z ){
-        pMem->flags = MEM_Null;
-      }
-      preserve = 0;
-    }else{
-      sqlite3_free(pMem->zMalloc);
-      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
-    }
-  }
+SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
+  int rc;
+  MemPage *pPage;
 
-  if( preserve && pMem->z && pMem->zMalloc && pMem->z!=pMem->zMalloc ){
-    memcpy(pMem->zMalloc, pMem->z, pMem->n);
+  assert( cursorHoldsMutex(pCur) );
+  rc = restoreCursorPosition(pCur);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
-  if( pMem->flags&MEM_Dyn && pMem->xDel ){
-    pMem->xDel((void *)(pMem->z));
+  pCur->atLast = 0;
+  if( CURSOR_INVALID==pCur->eState ){
+    *pRes = 1;
+    return SQLITE_OK;
   }
-
-  pMem->z = pMem->zMalloc;
-  pMem->flags &= ~(MEM_Ephem|MEM_Static);
-  pMem->xDel = 0;
-  return (pMem->z ? SQLITE_OK : SQLITE_NOMEM);
-}
-
-/*
-** Make the given Mem object MEM_Dyn.
-**
-** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemDynamicify(Mem *pMem){
-  int f;
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  expandBlob(pMem);
-  f = pMem->flags;
-  if( (f&(MEM_Str|MEM_Blob)) && pMem->z!=pMem->zMalloc ){
-    if( sqlite3VdbeMemGrow(pMem, pMem->n + 2, 1) ){
-      return SQLITE_NOMEM;
-    }
-    pMem->z[pMem->n] = 0;
-    pMem->z[pMem->n+1] = 0;
-    pMem->flags |= MEM_Term;
+  if( pCur->skipNext<0 ){
+    pCur->skipNext = 0;
+    *pRes = 0;
+    return SQLITE_OK;
   }
+  pCur->skipNext = 0;
 
-  return SQLITE_OK;
-}
-
-/*
-** If the given Mem* has a zero-filled tail, turn it into an ordinary
-** blob stored in dynamically allocated space.
-*/
-#ifndef SQLITE_OMIT_INCRBLOB
-SQLITE_PRIVATE int sqlite3VdbeMemExpandBlob(Mem *pMem){
-  if( pMem->flags & MEM_Zero ){
-    int nByte;
-    assert( pMem->flags&MEM_Blob );
-    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-
-    /* Set nByte to the number of bytes required to store the expanded blob. */
-    nByte = pMem->n + pMem->u.i;
-    if( nByte<=0 ){
-      nByte = 1;
+  pPage = pCur->apPage[pCur->iPage];
+  assert( pPage->isInit );
+  if( !pPage->leaf ){
+    int idx = pCur->aiIdx[pCur->iPage];
+    rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));
+    if( rc ){
+      return rc;
     }
-    if( sqlite3VdbeMemGrow(pMem, nByte, 1) ){
-      return SQLITE_NOMEM;
+    rc = moveToRightmost(pCur);
+  }else{
+    while( pCur->aiIdx[pCur->iPage]==0 ){
+      if( pCur->iPage==0 ){
+        pCur->eState = CURSOR_INVALID;
+        *pRes = 1;
+        return SQLITE_OK;
+      }
+      moveToParent(pCur);
     }
+    pCur->info.nSize = 0;
+    pCur->validNKey = 0;
 
-    memset(&pMem->z[pMem->n], 0, pMem->u.i);
-    pMem->n += pMem->u.i;
-    pMem->flags &= ~(MEM_Zero|MEM_Term);
+    pCur->aiIdx[pCur->iPage]--;
+    pPage = pCur->apPage[pCur->iPage];
+    if( pPage->intKey && !pPage->leaf ){
+      rc = sqlite3BtreePrevious(pCur, pRes);
+    }else{
+      rc = SQLITE_OK;
+    }
   }
-  return SQLITE_OK;
+  *pRes = 0;
+  return rc;
 }
-#endif
-
 
 /*
-** Make the given Mem object either MEM_Short or MEM_Dyn so that bytes
-** of the Mem.z[] array can be modified.
+** Allocate a new page from the database file.
 **
-** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem *pMem){
-  return sqlite3VdbeMemDynamicify(pMem);
-}
-
-/*
-** Make sure the given Mem is \u0000 terminated.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem *pMem){
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  if( (pMem->flags & MEM_Term)!=0 || (pMem->flags & MEM_Str)==0 ){
-    return SQLITE_OK;   /* Nothing to do */
-  }
-  if( sqlite3VdbeMemGrow(pMem, pMem->n+2, 1) ){
-    return SQLITE_NOMEM;
-  }
-  pMem->z[pMem->n] = 0;
-  pMem->z[pMem->n+1] = 0;
-  pMem->flags |= MEM_Term;
-  return SQLITE_OK;
-}
-
-/*
-** Add MEM_Str to the set of representations for the given Mem.  Numbers
-** are converted using sqlite3_snprintf().  Converting a BLOB to a string
-** is a no-op.
+** The new page is marked as dirty.  (In other words, sqlite3PagerWrite()
+** has already been called on the new page.)  The new page has also
+** been referenced and the calling routine is responsible for calling
+** sqlite3PagerUnref() on the new page when it is done.
 **
-** Existing representations MEM_Int and MEM_Real are *not* invalidated.
+** SQLITE_OK is returned on success.  Any other return value indicates
+** an error.  *ppPage and *pPgno are undefined in the event of an error.
+** Do not invoke sqlite3PagerUnref() on *ppPage if an error is returned.
 **
-** A MEM_Null value will never be passed to this function. This function is
-** used for converting values to text for returning to the user (i.e. via
-** sqlite3_value_text()), or for ensuring that values to be used as btree
-** keys are strings. In the former case a NULL pointer is returned the
-** user and the later is an internal programming error.
+** If the "nearby" parameter is not 0, then a (feeble) effort is made to 
+** locate a page close to the page number "nearby".  This can be used in an
+** attempt to keep related pages close to each other in the database file,
+** which in turn can make database access faster.
+**
+** If the "exact" parameter is not 0, and the page-number nearby exists 
+** anywhere on the free-list, then it is guarenteed to be returned. This
+** is only used by auto-vacuum databases when allocating a new table.
 */
-SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem *pMem, int enc){
-  int rc = SQLITE_OK;
-  int fg = pMem->flags;
-  const int nByte = 32;
-
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  assert( !(fg&MEM_Zero) );
-  assert( !(fg&(MEM_Str|MEM_Blob)) );
-  assert( fg&(MEM_Int|MEM_Real) );
-
-  if( sqlite3VdbeMemGrow(pMem, nByte, 0) ){
-    return SQLITE_NOMEM;
-  }
+static int allocateBtreePage(
+  BtShared *pBt, 
+  MemPage **ppPage, 
+  Pgno *pPgno, 
+  Pgno nearby,
+  u8 exact
+){
+  MemPage *pPage1;
+  int rc;
+  u32 n;     /* Number of pages on the freelist */
+  u32 k;     /* Number of leaves on the trunk of the freelist */
+  MemPage *pTrunk = 0;
+  MemPage *pPrevTrunk = 0;
+  Pgno mxPage;     /* Total size of the database file */
 
-  /* For a Real or Integer, use sqlite3_mprintf() to produce the UTF-8
-  ** string representation of the value. Then, if the required encoding
-  ** is UTF-16le or UTF-16be do a translation.
-  ** 
-  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
-  */
-  if( fg & MEM_Int ){
-    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
-  }else{
-    assert( fg & MEM_Real );
-    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
-  }
-  pMem->n = strlen(pMem->z);
-  pMem->enc = SQLITE_UTF8;
-  pMem->flags |= MEM_Str|MEM_Term;
-  sqlite3VdbeChangeEncoding(pMem, enc);
-  return rc;
-}
-
-/*
-** Memory cell pMem contains the context of an aggregate function.
-** This routine calls the finalize method for that function.  The
-** result of the aggregate is stored back into pMem.
-**
-** Return SQLITE_ERROR if the finalizer reports an error.  SQLITE_OK
-** otherwise.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){
-  int rc = SQLITE_OK;
-  if( pFunc && pFunc->xFinalize ){
-    sqlite3_context ctx;
-    assert( (pMem->flags & MEM_Null)!=0 || pFunc==pMem->u.pDef );
-    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-    ctx.s.flags = MEM_Null;
-    ctx.s.db = pMem->db;
-    ctx.s.zMalloc = 0;
-    ctx.pMem = pMem;
-    ctx.pFunc = pFunc;
-    ctx.isError = 0;
-    pFunc->xFinalize(&ctx);
-    assert( 0==(pMem->flags&MEM_Dyn) && !pMem->xDel );
-    sqlite3_free(pMem->zMalloc);
-    *pMem = ctx.s;
-    rc = (ctx.isError?SQLITE_ERROR:SQLITE_OK);
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  pPage1 = pBt->pPage1;
+  mxPage = pagerPagecount(pBt);
+  n = get4byte(&pPage1->aData[36]);
+  testcase( n==mxPage-1 );
+  if( n>=mxPage ){
+    return SQLITE_CORRUPT_BKPT;
   }
-  return rc;
-}
+  if( n>0 ){
+    /* There are pages on the freelist.  Reuse one of those pages. */
+    Pgno iTrunk;
+    u8 searchList = 0; /* If the free-list must be searched for 'nearby' */
+    
+    /* If the 'exact' parameter was true and a query of the pointer-map
+    ** shows that the page 'nearby' is somewhere on the free-list, then
+    ** the entire-list will be searched for that page.
+    */
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( exact && nearby<=mxPage ){
+      u8 eType;
+      assert( nearby>0 );
+      assert( pBt->autoVacuum );
+      rc = ptrmapGet(pBt, nearby, &eType, 0);
+      if( rc ) return rc;
+      if( eType==PTRMAP_FREEPAGE ){
+        searchList = 1;
+      }
+      *pPgno = nearby;
+    }
+#endif
 
-/*
-** If the memory cell contains a string value that must be freed by
-** invoking an external callback, free it now. Calling this function
-** does not free any Mem.zMalloc buffer.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p){
-  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
-  if( p->flags&MEM_Agg ){
-    sqlite3VdbeMemFinalize(p, p->u.pDef);
-    assert( (p->flags & MEM_Agg)==0 );
-    sqlite3VdbeMemRelease(p);
-  }else if( p->flags&MEM_Dyn && p->xDel ){
-    p->xDel((void *)p->z);
-    p->xDel = 0;
-  }
-}
+    /* Decrement the free-list count by 1. Set iTrunk to the index of the
+    ** first free-list trunk page. iPrevTrunk is initially 1.
+    */
+    rc = sqlite3PagerWrite(pPage1->pDbPage);
+    if( rc ) return rc;
+    put4byte(&pPage1->aData[36], n-1);
 
-/*
-** Release any memory held by the Mem. This may leave the Mem in an
-** inconsistent state, for example with (Mem.z==0) and
-** (Mem.type==SQLITE_TEXT).
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p){
-  sqlite3VdbeMemReleaseExternal(p);
-  sqlite3_free(p->zMalloc);
-  p->z = 0;
-  p->zMalloc = 0;
-  p->xDel = 0;
-}
+    /* The code within this loop is run only once if the 'searchList' variable
+    ** is not true. Otherwise, it runs once for each trunk-page on the
+    ** free-list until the page 'nearby' is located.
+    */
+    do {
+      pPrevTrunk = pTrunk;
+      if( pPrevTrunk ){
+        iTrunk = get4byte(&pPrevTrunk->aData[0]);
+      }else{
+        iTrunk = get4byte(&pPage1->aData[32]);
+      }
+      testcase( iTrunk==mxPage );
+      if( iTrunk>mxPage ){
+        rc = SQLITE_CORRUPT_BKPT;
+      }else{
+        rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0);
+      }
+      if( rc ){
+        pTrunk = 0;
+        goto end_allocate_page;
+      }
 
-/*
-** Convert a 64-bit IEEE double into a 64-bit signed integer.
-** If the double is too large, return 0x8000000000000000.
-**
-** Most systems appear to do this simply by assigning
-** variables and without the extra range tests.  But
-** there are reports that windows throws an expection
-** if the floating point value is out of range. (See ticket #2880.)
-** Because we do not completely understand the problem, we will
-** take the conservative approach and always do range tests
-** before attempting the conversion.
-*/
-static i64 doubleToInt64(double r){
-  /*
-  ** Many compilers we encounter do not define constants for the
-  ** minimum and maximum 64-bit integers, or they define them
-  ** inconsistently.  And many do not understand the "LL" notation.
-  ** So we define our own static constants here using nothing
-  ** larger than a 32-bit integer constant.
-  */
-  static const i64 maxInt = LARGEST_INT64;
-  static const i64 minInt = SMALLEST_INT64;
+      k = get4byte(&pTrunk->aData[4]);
+      if( k==0 && !searchList ){
+        /* The trunk has no leaves and the list is not being searched. 
+        ** So extract the trunk page itself and use it as the newly 
+        ** allocated page */
+        assert( pPrevTrunk==0 );
+        rc = sqlite3PagerWrite(pTrunk->pDbPage);
+        if( rc ){
+          goto end_allocate_page;
+        }
+        *pPgno = iTrunk;
+        memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
+        *ppPage = pTrunk;
+        pTrunk = 0;
+        TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
+      }else if( k>(u32)(pBt->usableSize/4 - 2) ){
+        /* Value of k is out of range.  Database corruption */
+        rc = SQLITE_CORRUPT_BKPT;
+        goto end_allocate_page;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      }else if( searchList && nearby==iTrunk ){
+        /* The list is being searched and this trunk page is the page
+        ** to allocate, regardless of whether it has leaves.
+        */
+        assert( *pPgno==iTrunk );
+        *ppPage = pTrunk;
+        searchList = 0;
+        rc = sqlite3PagerWrite(pTrunk->pDbPage);
+        if( rc ){
+          goto end_allocate_page;
+        }
+        if( k==0 ){
+          if( !pPrevTrunk ){
+            memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
+          }else{
+            memcpy(&pPrevTrunk->aData[0], &pTrunk->aData[0], 4);
+          }
+        }else{
+          /* The trunk page is required by the caller but it contains 
+          ** pointers to free-list leaves. The first leaf becomes a trunk
+          ** page in this case.
+          */
+          MemPage *pNewTrunk;
+          Pgno iNewTrunk = get4byte(&pTrunk->aData[8]);
+          if( iNewTrunk>mxPage ){ 
+            rc = SQLITE_CORRUPT_BKPT;
+            goto end_allocate_page;
+          }
+          testcase( iNewTrunk==mxPage );
+          rc = btreeGetPage(pBt, iNewTrunk, &pNewTrunk, 0);
+          if( rc!=SQLITE_OK ){
+            goto end_allocate_page;
+          }
+          rc = sqlite3PagerWrite(pNewTrunk->pDbPage);
+          if( rc!=SQLITE_OK ){
+            releasePage(pNewTrunk);
+            goto end_allocate_page;
+          }
+          memcpy(&pNewTrunk->aData[0], &pTrunk->aData[0], 4);
+          put4byte(&pNewTrunk->aData[4], k-1);
+          memcpy(&pNewTrunk->aData[8], &pTrunk->aData[12], (k-1)*4);
+          releasePage(pNewTrunk);
+          if( !pPrevTrunk ){
+            assert( sqlite3PagerIswriteable(pPage1->pDbPage) );
+            put4byte(&pPage1->aData[32], iNewTrunk);
+          }else{
+            rc = sqlite3PagerWrite(pPrevTrunk->pDbPage);
+            if( rc ){
+              goto end_allocate_page;
+            }
+            put4byte(&pPrevTrunk->aData[0], iNewTrunk);
+          }
+        }
+        pTrunk = 0;
+        TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
+#endif
+      }else if( k>0 ){
+        /* Extract a leaf from the trunk */
+        u32 closest;
+        Pgno iPage;
+        unsigned char *aData = pTrunk->aData;
+        rc = sqlite3PagerWrite(pTrunk->pDbPage);
+        if( rc ){
+          goto end_allocate_page;
+        }
+        if( nearby>0 ){
+          u32 i;
+          int dist;
+          closest = 0;
+          dist = get4byte(&aData[8]) - nearby;
+          if( dist<0 ) dist = -dist;
+          for(i=1; i<k; i++){
+            int d2 = get4byte(&aData[8+i*4]) - nearby;
+            if( d2<0 ) d2 = -d2;
+            if( d2<dist ){
+              closest = i;
+              dist = d2;
+            }
+          }
+        }else{
+          closest = 0;
+        }
 
-  if( r<(double)minInt ){
-    return minInt;
-  }else if( r>(double)maxInt ){
-    return minInt;
+        iPage = get4byte(&aData[8+closest*4]);
+        testcase( iPage==mxPage );
+        if( iPage>mxPage ){
+          rc = SQLITE_CORRUPT_BKPT;
+          goto end_allocate_page;
+        }
+        testcase( iPage==mxPage );
+        if( !searchList || iPage==nearby ){
+          int noContent;
+          *pPgno = iPage;
+          TRACE(("ALLOCATE: %d was leaf %d of %d on trunk %d"
+                 ": %d more free pages\n",
+                 *pPgno, closest+1, k, pTrunk->pgno, n-1));
+          if( closest<k-1 ){
+            memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
+          }
+          put4byte(&aData[4], k-1);
+          assert( sqlite3PagerIswriteable(pTrunk->pDbPage) );
+          noContent = !btreeGetHasContent(pBt, *pPgno);
+          rc = btreeGetPage(pBt, *pPgno, ppPage, noContent);
+          if( rc==SQLITE_OK ){
+            rc = sqlite3PagerWrite((*ppPage)->pDbPage);
+            if( rc!=SQLITE_OK ){
+              releasePage(*ppPage);
+            }
+          }
+          searchList = 0;
+        }
+      }
+      releasePage(pPrevTrunk);
+      pPrevTrunk = 0;
+    }while( searchList );
   }else{
-    return (i64)r;
+    /* There are no pages on the freelist, so create a new page at the
+    ** end of the file */
+    int nPage = pagerPagecount(pBt);
+    *pPgno = nPage + 1;
+
+    if( *pPgno==PENDING_BYTE_PAGE(pBt) ){
+      (*pPgno)++;
+    }
+
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pBt->autoVacuum && PTRMAP_ISPAGE(pBt, *pPgno) ){
+      /* If *pPgno refers to a pointer-map page, allocate two new pages
+      ** at the end of the file instead of one. The first allocated page
+      ** becomes a new pointer-map page, the second is used by the caller.
+      */
+      MemPage *pPg = 0;
+      TRACE(("ALLOCATE: %d from end of file (pointer-map page)\n", *pPgno));
+      assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
+      rc = btreeGetPage(pBt, *pPgno, &pPg, 0);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3PagerWrite(pPg->pDbPage);
+        releasePage(pPg);
+      }
+      if( rc ) return rc;
+      (*pPgno)++;
+      if( *pPgno==PENDING_BYTE_PAGE(pBt) ){ (*pPgno)++; }
+    }
+#endif
+
+    assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
+    rc = btreeGetPage(pBt, *pPgno, ppPage, 0);
+    if( rc ) return rc;
+    rc = sqlite3PagerWrite((*ppPage)->pDbPage);
+    if( rc!=SQLITE_OK ){
+      releasePage(*ppPage);
+    }
+    TRACE(("ALLOCATE: %d from end of file\n", *pPgno));
   }
-}
 
-/*
-** Return some kind of integer value which is the best we can do
-** at representing the value that *pMem describes as an integer.
-** If pMem is an integer, then the value is exact.  If pMem is
-** a floating-point then the value returned is the integer part.
-** If pMem is a string or blob, then we make an attempt to convert
-** it into a integer and return that.  If pMem is NULL, return 0.
-**
-** If pMem is a string, its encoding might be changed.
-*/
-SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem *pMem){
-  int flags;
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  flags = pMem->flags;
-  if( flags & MEM_Int ){
-    return pMem->u.i;
-  }else if( flags & MEM_Real ){
-    return doubleToInt64(pMem->r);
-  }else if( flags & (MEM_Str|MEM_Blob) ){
-    i64 value;
-    pMem->flags |= MEM_Str;
-    if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8)
-       || sqlite3VdbeMemNulTerminate(pMem) ){
-      return 0;
+  assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
+
+end_allocate_page:
+  releasePage(pTrunk);
+  releasePage(pPrevTrunk);
+  if( rc==SQLITE_OK ){
+    if( sqlite3PagerPageRefcount((*ppPage)->pDbPage)>1 ){
+      releasePage(*ppPage);
+      return SQLITE_CORRUPT_BKPT;
     }
-    assert( pMem->z );
-    sqlite3Atoi64(pMem->z, &value);
-    return value;
+    (*ppPage)->isInit = 0;
   }else{
-    return 0;
+    *ppPage = 0;
   }
+  return rc;
 }
 
 /*
-** Return the best representation of pMem that we can get into a
-** double.  If pMem is already a double or an integer, return its
-** value.  If it is a string or blob, try to convert it to a double.
-** If it is a NULL, return 0.0.
+** This function is used to add page iPage to the database file free-list. 
+** It is assumed that the page is not already a part of the free-list.
+**
+** The value passed as the second argument to this function is optional.
+** If the caller happens to have a pointer to the MemPage object 
+** corresponding to page iPage handy, it may pass it as the second value. 
+** Otherwise, it may pass NULL.
+**
+** If a pointer to a MemPage object is passed as the second argument,
+** its reference count is not altered by this function.
 */
-SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem *pMem){
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  if( pMem->flags & MEM_Real ){
-    return pMem->r;
-  }else if( pMem->flags & MEM_Int ){
-    return (double)pMem->u.i;
-  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
-    double val = 0.0;
-    pMem->flags |= MEM_Str;
-    if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8)
-       || sqlite3VdbeMemNulTerminate(pMem) ){
-      return 0.0;
-    }
-    assert( pMem->z );
-    sqlite3AtoF(pMem->z, &val);
-    return val;
+static int freePage2(BtShared *pBt, MemPage *pMemPage, Pgno iPage){
+  MemPage *pTrunk = 0;                /* Free-list trunk page */
+  Pgno iTrunk = 0;                    /* Page number of free-list trunk page */ 
+  MemPage *pPage1 = pBt->pPage1;      /* Local reference to page 1 */
+  MemPage *pPage;                     /* Page being freed. May be NULL. */
+  int rc;                             /* Return Code */
+  int nFree;                          /* Initial number of pages on free-list */
+
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( iPage>1 );
+  assert( !pMemPage || pMemPage->pgno==iPage );
+
+  if( pMemPage ){
+    pPage = pMemPage;
+    sqlite3PagerRef(pPage->pDbPage);
   }else{
-    return 0.0;
+    pPage = btreePageLookup(pBt, iPage);
   }
-}
 
-/*
-** The MEM structure is already a MEM_Real.  Try to also make it a
-** MEM_Int if we can.
-*/
-SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem *pMem){
-  assert( pMem->flags & MEM_Real );
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  /* Increment the free page count on pPage1 */
+  rc = sqlite3PagerWrite(pPage1->pDbPage);
+  if( rc ) goto freepage_out;
+  nFree = get4byte(&pPage1->aData[36]);
+  put4byte(&pPage1->aData[36], nFree+1);
 
-  pMem->u.i = doubleToInt64(pMem->r);
-  if( pMem->r==(double)pMem->u.i ){
-    pMem->flags |= MEM_Int;
+#ifdef SQLITE_SECURE_DELETE
+  /* If the SQLITE_SECURE_DELETE compile-time option is enabled, then
+  ** always fully overwrite deleted information with zeros.
+  */
+  if( (!pPage && (rc = btreeGetPage(pBt, iPage, &pPage, 0)))
+   ||            (rc = sqlite3PagerWrite(pPage->pDbPage))
+  ){
+    goto freepage_out;
   }
-}
+  memset(pPage->aData, 0, pPage->pBt->pageSize);
+#endif
 
-static void setTypeFlag(Mem *pMem, int f){
-  MemSetTypeFlag(pMem, f);
-}
+  /* If the database supports auto-vacuum, write an entry in the pointer-map
+  ** to indicate that the page is free.
+  */
+  if( ISAUTOVACUUM ){
+    ptrmapPut(pBt, iPage, PTRMAP_FREEPAGE, 0, &rc);
+    if( rc ) goto freepage_out;
+  }
 
-/*
-** Convert pMem to type integer.  Invalidate any prior representations.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem *pMem){
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  pMem->u.i = sqlite3VdbeIntValue(pMem);
-  setTypeFlag(pMem, MEM_Int);
-  return SQLITE_OK;
-}
+  /* Now manipulate the actual database free-list structure. There are two
+  ** possibilities. If the free-list is currently empty, or if the first
+  ** trunk page in the free-list is full, then this page will become a
+  ** new free-list trunk page. Otherwise, it will become a leaf of the
+  ** first trunk page in the current free-list. This block tests if it
+  ** is possible to add the page as a new free-list leaf.
+  */
+  if( nFree!=0 ){
+    u32 nLeaf;                /* Initial number of leaf cells on trunk page */
 
-/*
-** Convert pMem so that it is of type MEM_Real.
-** Invalidate any prior representations.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem *pMem){
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  pMem->r = sqlite3VdbeRealValue(pMem);
-  setTypeFlag(pMem, MEM_Real);
-  return SQLITE_OK;
-}
+    iTrunk = get4byte(&pPage1->aData[32]);
+    rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0);
+    if( rc!=SQLITE_OK ){
+      goto freepage_out;
+    }
 
-/*
-** Convert pMem so that it has types MEM_Real or MEM_Int or both.
-** Invalidate any prior representations.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem *pMem){
-  double r1, r2;
-  i64 i;
-  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 );
-  assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  r1 = sqlite3VdbeRealValue(pMem);
-  i = doubleToInt64(r1);
-  r2 = (double)i;
-  if( r1==r2 ){
-    sqlite3VdbeMemIntegerify(pMem);
-  }else{
-    pMem->r = r1;
-    setTypeFlag(pMem, MEM_Real);
+    nLeaf = get4byte(&pTrunk->aData[4]);
+    assert( pBt->usableSize>32 );
+    if( nLeaf > (u32)pBt->usableSize/4 - 2 ){
+      rc = SQLITE_CORRUPT_BKPT;
+      goto freepage_out;
+    }
+    if( nLeaf < (u32)pBt->usableSize/4 - 8 ){
+      /* In this case there is room on the trunk page to insert the page
+      ** being freed as a new leaf.
+      **
+      ** Note that the trunk page is not really full until it contains
+      ** usableSize/4 - 2 entries, not usableSize/4 - 8 entries as we have
+      ** coded.  But due to a coding error in versions of SQLite prior to
+      ** 3.6.0, databases with freelist trunk pages holding more than
+      ** usableSize/4 - 8 entries will be reported as corrupt.  In order
+      ** to maintain backwards compatibility with older versions of SQLite,
+      ** we will continue to restrict the number of entries to usableSize/4 - 8
+      ** for now.  At some point in the future (once everyone has upgraded
+      ** to 3.6.0 or later) we should consider fixing the conditional above
+      ** to read "usableSize/4-2" instead of "usableSize/4-8".
+      */
+      rc = sqlite3PagerWrite(pTrunk->pDbPage);
+      if( rc==SQLITE_OK ){
+        put4byte(&pTrunk->aData[4], nLeaf+1);
+        put4byte(&pTrunk->aData[8+nLeaf*4], iPage);
+#ifndef SQLITE_SECURE_DELETE
+        if( pPage ){
+          sqlite3PagerDontWrite(pPage->pDbPage);
+        }
+#endif
+        rc = btreeSetHasContent(pBt, iPage);
+      }
+      TRACE(("FREE-PAGE: %d leaf on trunk page %d\n",pPage->pgno,pTrunk->pgno));
+      goto freepage_out;
+    }
   }
-  return SQLITE_OK;
-}
-
-/*
-** Delete any previous value and set the value stored in *pMem to NULL.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem *pMem){
-  setTypeFlag(pMem, MEM_Null);
-  pMem->type = SQLITE_NULL;
-}
 
-/*
-** Delete any previous value and set the value to be a BLOB of length
-** n containing all zeros.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem *pMem, int n){
-  sqlite3VdbeMemRelease(pMem);
-  setTypeFlag(pMem, MEM_Blob);
-  pMem->flags = MEM_Blob|MEM_Zero;
-  pMem->type = SQLITE_BLOB;
-  pMem->n = 0;
-  if( n<0 ) n = 0;
-  pMem->u.i = n;
-  pMem->enc = SQLITE_UTF8;
-}
+  /* If control flows to this point, then it was not possible to add the
+  ** the page being freed as a leaf page of the first trunk in the free-list.
+  ** Possibly because the free-list is empty, or possibly because the 
+  ** first trunk in the free-list is full. Either way, the page being freed
+  ** will become the new first trunk page in the free-list.
+  */
+  if( pPage==0 && SQLITE_OK!=(rc = btreeGetPage(pBt, iPage, &pPage, 0)) ){
+    goto freepage_out;
+  }
+  rc = sqlite3PagerWrite(pPage->pDbPage);
+  if( rc!=SQLITE_OK ){
+    goto freepage_out;
+  }
+  put4byte(pPage->aData, iTrunk);
+  put4byte(&pPage->aData[4], 0);
+  put4byte(&pPage1->aData[32], iPage);
+  TRACE(("FREE-PAGE: %d new trunk page replacing %d\n", pPage->pgno, iTrunk));
 
-/*
-** Delete any previous value and set the value stored in *pMem to val,
-** manifest type INTEGER.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){
-  sqlite3VdbeMemRelease(pMem);
-  pMem->u.i = val;
-  pMem->flags = MEM_Int;
-  pMem->type = SQLITE_INTEGER;
+freepage_out:
+  if( pPage ){
+    pPage->isInit = 0;
+  }
+  releasePage(pPage);
+  releasePage(pTrunk);
+  return rc;
 }
-
-/*
-** Delete any previous value and set the value stored in *pMem to val,
-** manifest type REAL.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
-  if( sqlite3IsNaN(val) ){
-    sqlite3VdbeMemSetNull(pMem);
-  }else{
-    sqlite3VdbeMemRelease(pMem);
-    pMem->r = val;
-    pMem->flags = MEM_Real;
-    pMem->type = SQLITE_FLOAT;
+static void freePage(MemPage *pPage, int *pRC){
+  if( (*pRC)==SQLITE_OK ){
+    *pRC = freePage2(pPage->pBt, pPage, pPage->pgno);
   }
 }
 
 /*
-** Return true if the Mem object contains a TEXT or BLOB that is
-** too large - whose size exceeds SQLITE_MAX_LENGTH.
+** Free any overflow pages associated with the given Cell.
 */
-SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem *p){
-  assert( p->db!=0 );
-  if( p->flags & (MEM_Str|MEM_Blob) ){
-    int n = p->n;
-    if( p->flags & MEM_Zero ){
-      n += p->u.i;
+static int clearCell(MemPage *pPage, unsigned char *pCell){
+  BtShared *pBt = pPage->pBt;
+  CellInfo info;
+  Pgno ovflPgno;
+  int rc;
+  int nOvfl;
+  u16 ovflPageSize;
+
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  btreeParseCellPtr(pPage, pCell, &info);
+  if( info.iOverflow==0 ){
+    return SQLITE_OK;  /* No overflow pages. Return without doing anything */
+  }
+  ovflPgno = get4byte(&pCell[info.iOverflow]);
+  assert( pBt->usableSize > 4 );
+  ovflPageSize = pBt->usableSize - 4;
+  nOvfl = (info.nPayload - info.nLocal + ovflPageSize - 1)/ovflPageSize;
+  assert( ovflPgno==0 || nOvfl>0 );
+  while( nOvfl-- ){
+    Pgno iNext = 0;
+    MemPage *pOvfl = 0;
+    if( ovflPgno<2 || ovflPgno>pagerPagecount(pBt) ){
+      /* 0 is not a legal page number and page 1 cannot be an 
+      ** overflow page. Therefore if ovflPgno<2 or past the end of the 
+      ** file the database must be corrupt. */
+      return SQLITE_CORRUPT_BKPT;
     }
-    return n>p->db->aLimit[SQLITE_LIMIT_LENGTH];
+    if( nOvfl ){
+      rc = getOverflowPage(pBt, ovflPgno, &pOvfl, &iNext);
+      if( rc ) return rc;
+    }
+    rc = freePage2(pBt, pOvfl, ovflPgno);
+    if( pOvfl ){
+      sqlite3PagerUnref(pOvfl->pDbPage);
+    }
+    if( rc ) return rc;
+    ovflPgno = iNext;
   }
-  return 0; 
+  return SQLITE_OK;
 }
 
 /*
-** Size of struct Mem not including the Mem.zMalloc member.
+** Create the byte sequence used to represent a cell on page pPage
+** and write that byte sequence into pCell[].  Overflow pages are
+** allocated and filled in as necessary.  The calling procedure
+** is responsible for making sure sufficient space has been allocated
+** for pCell[].
+**
+** Note that pCell does not necessary need to point to the pPage->aData
+** area.  pCell might point to some temporary storage.  The cell will
+** be constructed in this temporary area then copied into pPage->aData
+** later.
 */
-#define MEMCELLSIZE (size_t)(&(((Mem *)0)->zMalloc))
-
-/*
-** Make an shallow copy of pFrom into pTo.  Prior contents of
-** pTo are freed.  The pFrom->z field is not duplicated.  If
-** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
-** and flags gets srcType (either MEM_Ephem or MEM_Static).
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
-  sqlite3VdbeMemReleaseExternal(pTo);
-  memcpy(pTo, pFrom, MEMCELLSIZE);
-  pTo->xDel = 0;
-  if( (pFrom->flags&MEM_Dyn)!=0 || pFrom->z==pFrom->zMalloc ){
-    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
-    assert( srcType==MEM_Ephem || srcType==MEM_Static );
-    pTo->flags |= srcType;
-  }
-}
+static int fillInCell(
+  MemPage *pPage,                /* The page that contains the cell */
+  unsigned char *pCell,          /* Complete text of the cell */
+  const void *pKey, i64 nKey,    /* The key */
+  const void *pData,int nData,   /* The data */
+  int nZero,                     /* Extra zero bytes to append to pData */
+  int *pnSize                    /* Write cell size here */
+){
+  int nPayload;
+  const u8 *pSrc;
+  int nSrc, n, rc;
+  int spaceLeft;
+  MemPage *pOvfl = 0;
+  MemPage *pToRelease = 0;
+  unsigned char *pPrior;
+  unsigned char *pPayload;
+  BtShared *pBt = pPage->pBt;
+  Pgno pgnoOvfl = 0;
+  int nHeader;
+  CellInfo info;
 
-/*
-** Make a full copy of pFrom into pTo.  Prior contents of pTo are
-** freed before the copy is made.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
-  int rc = SQLITE_OK;
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
 
-  sqlite3VdbeMemReleaseExternal(pTo);
-  memcpy(pTo, pFrom, MEMCELLSIZE);
-  pTo->flags &= ~MEM_Dyn;
+  /* pPage is not necessarily writeable since pCell might be auxiliary
+  ** buffer space that is separate from the pPage buffer area */
+  assert( pCell<pPage->aData || pCell>=&pPage->aData[pBt->pageSize]
+            || sqlite3PagerIswriteable(pPage->pDbPage) );
 
-  if( pTo->flags&(MEM_Str|MEM_Blob) ){
-    if( 0==(pFrom->flags&MEM_Static) ){
-      pTo->flags |= MEM_Ephem;
-      rc = sqlite3VdbeMemMakeWriteable(pTo);
+  /* Fill in the header. */
+  nHeader = 0;
+  if( !pPage->leaf ){
+    nHeader += 4;
+  }
+  if( pPage->hasData ){
+    nHeader += putVarint(&pCell[nHeader], nData+nZero);
+  }else{
+    nData = nZero = 0;
+  }
+  nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey);
+  btreeParseCellPtr(pPage, pCell, &info);
+  assert( info.nHeader==nHeader );
+  assert( info.nKey==nKey );
+  assert( info.nData==(u32)(nData+nZero) );
+  
+  /* Fill in the payload */
+  nPayload = nData + nZero;
+  if( pPage->intKey ){
+    pSrc = pData;
+    nSrc = nData;
+    nData = 0;
+  }else{ 
+    if( NEVER(nKey>0x7fffffff || pKey==0) ){
+      return SQLITE_CORRUPT_BKPT;
     }
+    nPayload += (int)nKey;
+    pSrc = pKey;
+    nSrc = (int)nKey;
   }
+  *pnSize = info.nSize;
+  spaceLeft = info.nLocal;
+  pPayload = &pCell[nHeader];
+  pPrior = &pCell[info.iOverflow];
 
-  return rc;
-}
+  while( nPayload>0 ){
+    if( spaceLeft==0 ){
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      Pgno pgnoPtrmap = pgnoOvfl; /* Overflow page pointer-map entry page */
+      if( pBt->autoVacuum ){
+        do{
+          pgnoOvfl++;
+        } while( 
+          PTRMAP_ISPAGE(pBt, pgnoOvfl) || pgnoOvfl==PENDING_BYTE_PAGE(pBt) 
+        );
+      }
+#endif
+      rc = allocateBtreePage(pBt, &pOvfl, &pgnoOvfl, pgnoOvfl, 0);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      /* If the database supports auto-vacuum, and the second or subsequent
+      ** overflow page is being allocated, add an entry to the pointer-map
+      ** for that page now. 
+      **
+      ** If this is the first overflow page, then write a partial entry 
+      ** to the pointer-map. If we write nothing to this pointer-map slot,
+      ** then the optimistic overflow chain processing in clearCell()
+      ** may misinterpret the uninitialised values and delete the
+      ** wrong pages from the database.
+      */
+      if( pBt->autoVacuum && rc==SQLITE_OK ){
+        u8 eType = (pgnoPtrmap?PTRMAP_OVERFLOW2:PTRMAP_OVERFLOW1);
+        ptrmapPut(pBt, pgnoOvfl, eType, pgnoPtrmap, &rc);
+        if( rc ){
+          releasePage(pOvfl);
+        }
+      }
+#endif
+      if( rc ){
+        releasePage(pToRelease);
+        return rc;
+      }
 
-/*
-** Transfer the contents of pFrom to pTo. Any existing value in pTo is
-** freed. If pFrom contains ephemeral data, a copy is made.
-**
-** pFrom contains an SQL NULL when this routine returns.
-*/
-SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem *pTo, Mem *pFrom){
-  assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) );
-  assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) );
-  assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db );
+      /* If pToRelease is not zero than pPrior points into the data area
+      ** of pToRelease.  Make sure pToRelease is still writeable. */
+      assert( pToRelease==0 || sqlite3PagerIswriteable(pToRelease->pDbPage) );
 
-  sqlite3VdbeMemRelease(pTo);
-  memcpy(pTo, pFrom, sizeof(Mem));
-  pFrom->flags = MEM_Null;
-  pFrom->xDel = 0;
-  pFrom->zMalloc = 0;
-}
+      /* If pPrior is part of the data area of pPage, then make sure pPage
+      ** is still writeable */
+      assert( pPrior<pPage->aData || pPrior>=&pPage->aData[pBt->pageSize]
+            || sqlite3PagerIswriteable(pPage->pDbPage) );
 
-/*
-** Change the value of a Mem to be a string or a BLOB.
-**
-** The memory management strategy depends on the value of the xDel
-** parameter. If the value passed is SQLITE_TRANSIENT, then the 
-** string is copied into a (possibly existing) buffer managed by the 
-** Mem structure. Otherwise, any existing buffer is freed and the
-** pointer copied.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemSetStr(
-  Mem *pMem,          /* Memory cell to set to string value */
-  const char *z,      /* String pointer */
-  int n,              /* Bytes in string, or negative */
-  u8 enc,             /* Encoding of z.  0 for BLOBs */
-  void (*xDel)(void*) /* Destructor function */
-){
-  int nByte = n;      /* New value for pMem->n */
-  int flags = 0;      /* New value for pMem->flags */
+      put4byte(pPrior, pgnoOvfl);
+      releasePage(pToRelease);
+      pToRelease = pOvfl;
+      pPrior = pOvfl->aData;
+      put4byte(pPrior, 0);
+      pPayload = &pOvfl->aData[4];
+      spaceLeft = pBt->usableSize - 4;
+    }
+    n = nPayload;
+    if( n>spaceLeft ) n = spaceLeft;
 
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+    /* If pToRelease is not zero than pPayload points into the data area
+    ** of pToRelease.  Make sure pToRelease is still writeable. */
+    assert( pToRelease==0 || sqlite3PagerIswriteable(pToRelease->pDbPage) );
 
-  /* If z is a NULL pointer, set pMem to contain an SQL NULL. */
-  if( !z ){
-    sqlite3VdbeMemSetNull(pMem);
-    return SQLITE_OK;
-  }
+    /* If pPayload is part of the data area of pPage, then make sure pPage
+    ** is still writeable */
+    assert( pPayload<pPage->aData || pPayload>=&pPage->aData[pBt->pageSize]
+            || sqlite3PagerIswriteable(pPage->pDbPage) );
 
-  flags = (enc==0?MEM_Blob:MEM_Str);
-  if( nByte<0 ){
-    assert( enc!=0 );
-    if( enc==SQLITE_UTF8 ){
-      for(nByte=0; z[nByte]; nByte++){}
+    if( nSrc>0 ){
+      if( n>nSrc ) n = nSrc;
+      assert( pSrc );
+      memcpy(pPayload, pSrc, n);
     }else{
-      for(nByte=0; z[nByte] | z[nByte+1]; nByte+=2){}
-    }
-    flags |= MEM_Term;
-  }
-
-  /* The following block sets the new values of Mem.z and Mem.xDel. It
-  ** also sets a flag in local variable "flags" to indicate the memory
-  ** management (one of MEM_Dyn or MEM_Static).
-  */
-  if( xDel==SQLITE_TRANSIENT ){
-    int nAlloc = nByte;
-    if( flags&MEM_Term ){
-      nAlloc += (enc==SQLITE_UTF8?1:2);
+      memset(pPayload, 0, n);
     }
-    if( sqlite3VdbeMemGrow(pMem, nAlloc, 0) ){
-      return SQLITE_NOMEM;
+    nPayload -= n;
+    pPayload += n;
+    pSrc += n;
+    nSrc -= n;
+    spaceLeft -= n;
+    if( nSrc==0 ){
+      nSrc = nData;
+      pSrc = pData;
     }
-    memcpy(pMem->z, z, nAlloc);
-  }else{
-    sqlite3VdbeMemRelease(pMem);
-    pMem->z = (char *)z;
-    pMem->xDel = xDel;
-    flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
   }
+  releasePage(pToRelease);
+  return SQLITE_OK;
+}
 
-  pMem->n = nByte;
-  pMem->flags = flags;
-  pMem->enc = (enc==0 ? SQLITE_UTF8 : enc);
-  pMem->type = (enc==0 ? SQLITE_BLOB : SQLITE_TEXT);
+/*
+** Remove the i-th cell from pPage.  This routine effects pPage only.
+** The cell content is not freed or deallocated.  It is assumed that
+** the cell content has been copied someplace else.  This routine just
+** removes the reference to the cell from pPage.
+**
+** "sz" must be the number of bytes in the cell.
+*/
+static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
+  int i;          /* Loop counter */
+  int pc;         /* Offset to cell content of cell being deleted */
+  u8 *data;       /* pPage->aData */
+  u8 *ptr;        /* Used to move bytes around within data[] */
+  int rc;         /* The return code */
+  int hdr;        /* Beginning of the header.  0 most pages.  100 page 1 */
 
-#ifndef SQLITE_OMIT_UTF16
-  if( pMem->enc!=SQLITE_UTF8 && sqlite3VdbeMemHandleBom(pMem) ){
-    return SQLITE_NOMEM;
-  }
-#endif
+  if( *pRC ) return;
 
-  return SQLITE_OK;
+  assert( idx>=0 && idx<pPage->nCell );
+  assert( sz==cellSize(pPage, idx) );
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  data = pPage->aData;
+  ptr = &data[pPage->cellOffset + 2*idx];
+  pc = get2byte(ptr);
+  hdr = pPage->hdrOffset;
+  testcase( pc==get2byte(&data[hdr+5]) );
+  testcase( pc+sz==pPage->pBt->usableSize );
+  if( pc < get2byte(&data[hdr+5]) || pc+sz > pPage->pBt->usableSize ){
+    *pRC = SQLITE_CORRUPT_BKPT;
+    return;
+  }
+  rc = freeSpace(pPage, pc, sz);
+  if( rc ){
+    *pRC = rc;
+    return;
+  }
+  for(i=idx+1; i<pPage->nCell; i++, ptr+=2){
+    ptr[0] = ptr[2];
+    ptr[1] = ptr[3];
+  }
+  pPage->nCell--;
+  put2byte(&data[hdr+3], pPage->nCell);
+  pPage->nFree += 2;
 }
 
 /*
-** Compare the values contained by the two memory cells, returning
-** negative, zero or positive if pMem1 is less than, equal to, or greater
-** than pMem2. Sorting order is NULL's first, followed by numbers (integers
-** and reals) sorted numerically, followed by text ordered by the collating
-** sequence pColl and finally blob's ordered by memcmp().
+** Insert a new cell on pPage at cell index "i".  pCell points to the
+** content of the cell.
 **
-** Two NULL values are considered equal by this function.
+** If the cell content will fit on the page, then put it there.  If it
+** will not fit, then make a copy of the cell content into pTemp if
+** pTemp is not null.  Regardless of pTemp, allocate a new entry
+** in pPage->aOvfl[] and make it point to the cell content (either
+** in pTemp or the original pCell) and also record its index. 
+** Allocating a new entry in pPage->aCell[] implies that 
+** pPage->nOverflow is incremented.
+**
+** If nSkip is non-zero, then do not copy the first nSkip bytes of the
+** cell. The caller will overwrite them after this function returns. If
+** nSkip is non-zero, then pCell may not point to an invalid memory location 
+** (but pCell+nSkip is always valid).
 */
-SQLITE_PRIVATE int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
-  int rc;
-  int f1, f2;
-  int combined_flags;
+static void insertCell(
+  MemPage *pPage,   /* Page into which we are copying */
+  int i,            /* New cell becomes the i-th cell of the page */
+  u8 *pCell,        /* Content of the new cell */
+  int sz,           /* Bytes of content in pCell */
+  u8 *pTemp,        /* Temp storage space for pCell, if needed */
+  Pgno iChild,      /* If non-zero, replace first 4 bytes with this value */
+  int *pRC          /* Read and write return code from here */
+){
+  int idx;          /* Where to write new cell content in data[] */
+  int j;            /* Loop counter */
+  int end;          /* First byte past the last cell pointer in data[] */
+  int ins;          /* Index in data[] where new cell pointer is inserted */
+  int cellOffset;   /* Address of first cell pointer in data[] */
+  u8 *data;         /* The content of the whole page */
+  u8 *ptr;          /* Used for moving information around in data[] */
 
-  /* Interchange pMem1 and pMem2 if the collating sequence specifies
-  ** DESC order.
-  */
-  f1 = pMem1->flags;
-  f2 = pMem2->flags;
-  combined_flags = f1|f2;
- 
-  /* If one value is NULL, it is less than the other. If both values
-  ** are NULL, return 0.
-  */
-  if( combined_flags&MEM_Null ){
-    return (f2&MEM_Null) - (f1&MEM_Null);
-  }
+  int nSkip = (iChild ? 4 : 0);
 
-  /* If one value is a number and the other is not, the number is less.
-  ** If both are numbers, compare as reals if one is a real, or as integers
-  ** if both values are integers.
-  */
-  if( combined_flags&(MEM_Int|MEM_Real) ){
-    if( !(f1&(MEM_Int|MEM_Real)) ){
-      return 1;
+  if( *pRC ) return;
+
+  assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
+  assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( pPage->nOverflow<=ArraySize(pPage->aOvfl) );
+  assert( sz==cellSizePtr(pPage, pCell) );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  if( pPage->nOverflow || sz+2>pPage->nFree ){
+    if( pTemp ){
+      memcpy(pTemp+nSkip, pCell+nSkip, sz-nSkip);
+      pCell = pTemp;
     }
-    if( !(f2&(MEM_Int|MEM_Real)) ){
-      return -1;
+    if( iChild ){
+      put4byte(pCell, iChild);
     }
-    if( (f1 & f2 & MEM_Int)==0 ){
-      double r1, r2;
-      if( (f1&MEM_Real)==0 ){
-        r1 = pMem1->u.i;
-      }else{
-        r1 = pMem1->r;
-      }
-      if( (f2&MEM_Real)==0 ){
-        r2 = pMem2->u.i;
-      }else{
-        r2 = pMem2->r;
-      }
-      if( r1<r2 ) return -1;
-      if( r1>r2 ) return 1;
-      return 0;
-    }else{
-      assert( f1&MEM_Int );
-      assert( f2&MEM_Int );
-      if( pMem1->u.i < pMem2->u.i ) return -1;
-      if( pMem1->u.i > pMem2->u.i ) return 1;
-      return 0;
+    j = pPage->nOverflow++;
+    assert( j<(int)(sizeof(pPage->aOvfl)/sizeof(pPage->aOvfl[0])) );
+    pPage->aOvfl[j].pCell = pCell;
+    pPage->aOvfl[j].idx = (u16)i;
+  }else{
+    int rc = sqlite3PagerWrite(pPage->pDbPage);
+    if( rc!=SQLITE_OK ){
+      *pRC = rc;
+      return;
     }
-  }
-
-  /* If one value is a string and the other is a blob, the string is less.
-  ** If both are strings, compare using the collating functions.
-  */
-  if( combined_flags&MEM_Str ){
-    if( (f1 & MEM_Str)==0 ){
-      return 1;
+    assert( sqlite3PagerIswriteable(pPage->pDbPage) );
+    data = pPage->aData;
+    cellOffset = pPage->cellOffset;
+    end = cellOffset + 2*pPage->nCell;
+    ins = cellOffset + 2*i;
+    rc = allocateSpace(pPage, sz, &idx);
+    if( rc ){ *pRC = rc; return; }
+    /* The allocateSpace() routine guarantees the following two properties
+    ** if it returns success */
+    assert( idx >= end+2 );
+    assert( idx+sz <= pPage->pBt->usableSize );
+    pPage->nCell++;
+    pPage->nFree -= (u16)(2 + sz);
+    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
+    if( iChild ){
+      put4byte(&data[idx], iChild);
     }
-    if( (f2 & MEM_Str)==0 ){
-      return -1;
+    for(j=end, ptr=&data[j]; j>ins; j-=2, ptr-=2){
+      ptr[0] = ptr[-2];
+      ptr[1] = ptr[-1];
     }
+    put2byte(&data[ins], idx);
+    put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pPage->pBt->autoVacuum ){
+      /* The cell may contain a pointer to an overflow page. If so, write
+      ** the entry for the overflow page into the pointer map.
+      */
+      ptrmapPutOvflPtr(pPage, pCell, pRC);
+    }
+#endif
+  }
+}
 
-    assert( pMem1->enc==pMem2->enc );
-    assert( pMem1->enc==SQLITE_UTF8 || 
-            pMem1->enc==SQLITE_UTF16LE || pMem1->enc==SQLITE_UTF16BE );
+/*
+** Add a list of cells to a page.  The page should be initially empty.
+** The cells are guaranteed to fit on the page.
+*/
+static void assemblePage(
+  MemPage *pPage,   /* The page to be assemblied */
+  int nCell,        /* The number of cells to add to this page */
+  u8 **apCell,      /* Pointers to cell bodies */
+  u16 *aSize        /* Sizes of the cells */
+){
+  int i;            /* Loop counter */
+  u8 *pCellptr;     /* Address of next cell pointer */
+  int cellbody;     /* Address of next cell body */
+  u8 * const data = pPage->aData;             /* Pointer to data for pPage */
+  const int hdr = pPage->hdrOffset;           /* Offset of header on pPage */
+  const int nUsable = pPage->pBt->usableSize; /* Usable size of page */
 
-    /* The collation sequence must be defined at this point, even if
-    ** the user deletes the collation sequence after the vdbe program is
-    ** compiled (this was not always the case).
-    */
-    assert( !pColl || pColl->xCmp );
+  assert( pPage->nOverflow==0 );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( nCell>=0 && nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
 
-    if( pColl ){
-      if( pMem1->enc==pColl->enc ){
-        /* The strings are already in the correct encoding.  Call the
-        ** comparison function directly */
-        return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z);
-      }else{
-        u8 origEnc = pMem1->enc;
-        const void *v1, *v2;
-        int n1, n2;
-        /* Convert the strings into the encoding that the comparison
-        ** function expects */
-        v1 = sqlite3ValueText((sqlite3_value*)pMem1, pColl->enc);
-        n1 = v1==0 ? 0 : pMem1->n;
-        assert( n1==sqlite3ValueBytes((sqlite3_value*)pMem1, pColl->enc) );
-        v2 = sqlite3ValueText((sqlite3_value*)pMem2, pColl->enc);
-        n2 = v2==0 ? 0 : pMem2->n;
-        assert( n2==sqlite3ValueBytes((sqlite3_value*)pMem2, pColl->enc) );
-        /* Do the comparison */
-        rc = pColl->xCmp(pColl->pUser, n1, v1, n2, v2);
-        /* Convert the strings back into the database encoding */
-        sqlite3ValueText((sqlite3_value*)pMem1, origEnc);
-        sqlite3ValueText((sqlite3_value*)pMem2, origEnc);
-        return rc;
-      }
-    }
-    /* If a NULL pointer was passed as the collate function, fall through
-    ** to the blob case and use memcmp().  */
-  }
- 
-  /* Both values must be blobs.  Compare using memcmp().  */
-  rc = memcmp(pMem1->z, pMem2->z, (pMem1->n>pMem2->n)?pMem2->n:pMem1->n);
-  if( rc==0 ){
-    rc = pMem1->n - pMem2->n;
+  /* Check that the page has just been zeroed by zeroPage() */
+  assert( pPage->nCell==0 );
+  assert( get2byte(&data[hdr+5])==nUsable );
+
+  pCellptr = &data[pPage->cellOffset + nCell*2];
+  cellbody = nUsable;
+  for(i=nCell-1; i>=0; i--){
+    pCellptr -= 2;
+    cellbody -= aSize[i];
+    put2byte(pCellptr, cellbody);
+    memcpy(&data[cellbody], apCell[i], aSize[i]);
   }
-  return rc;
+  put2byte(&data[hdr+3], nCell);
+  put2byte(&data[hdr+5], cellbody);
+  pPage->nFree -= (nCell*2 + nUsable - cellbody);
+  pPage->nCell = (u16)nCell;
 }
 
 /*
-** Move data out of a btree key or data field and into a Mem structure.
-** The data or key is taken from the entry that pCur is currently pointing
-** to.  offset and amt determine what portion of the data or key to retrieve.
-** key is true to get the key or false to get data.  The result is written
-** into the pMem element.
+** The following parameters determine how many adjacent pages get involved
+** in a balancing operation.  NN is the number of neighbors on either side
+** of the page that participate in the balancing operation.  NB is the
+** total number of pages that participate, including the target page and
+** NN neighbors on either side.
 **
-** The pMem structure is assumed to be uninitialized.  Any prior content
-** is overwritten without being freed.
+** The minimum value of NN is 1 (of course).  Increasing NN above 1
+** (to 2 or 3) gives a modest improvement in SELECT and DELETE performance
+** in exchange for a larger degradation in INSERT and UPDATE performance.
+** The value of NN appears to give the best results overall.
+*/
+#define NN 1             /* Number of neighbors on either side of pPage */
+#define NB (NN*2+1)      /* Total pages involved in the balance */
+
+
+#ifndef SQLITE_OMIT_QUICKBALANCE
+/*
+** This version of balance() handles the common special case where
+** a new entry is being inserted on the extreme right-end of the
+** tree, in other words, when the new entry will become the largest
+** entry in the tree.
 **
-** If this routine fails for any reason (malloc returns NULL or unable
-** to read from the disk) then the pMem is left in an inconsistent state.
+** Instead of trying to balance the 3 right-most leaf pages, just add
+** a new page to the right-hand side and put the one new entry in
+** that page.  This leaves the right side of the tree somewhat
+** unbalanced.  But odds are that we will be inserting new entries
+** at the end soon afterwards so the nearly empty page will quickly
+** fill up.  On average.
+**
+** pPage is the leaf page which is the right-most page in the tree.
+** pParent is its parent.  pPage must have a single overflow entry
+** which is also the right-most entry on the page.
+**
+** The pSpace buffer is used to store a temporary copy of the divider
+** cell that will be inserted into pParent. Such a cell consists of a 4
+** byte page number followed by a variable length integer. In other
+** words, at most 13 bytes. Hence the pSpace buffer must be at
+** least 13 bytes in size.
 */
-SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(
-  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
-  int offset,       /* Offset from the start of data to return bytes from. */
-  int amt,          /* Number of bytes to return. */
-  int key,          /* If true, retrieve from the btree key, not data. */
-  Mem *pMem         /* OUT: Return data in this Mem structure. */
-){
-  char *zData;       /* Data from the btree layer */
-  int available = 0; /* Number of bytes available on the local btree page */
-  sqlite3 *db;       /* Database connection */
-  int rc = SQLITE_OK;
+static int balance_quick(MemPage *pParent, MemPage *pPage, u8 *pSpace){
+  BtShared *const pBt = pPage->pBt;    /* B-Tree Database */
+  MemPage *pNew;                       /* Newly allocated page */
+  int rc;                              /* Return Code */
+  Pgno pgnoNew;                        /* Page number of pNew */
 
-  db = sqlite3BtreeCursorDb(pCur);
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( key ){
-    zData = (char *)sqlite3BtreeKeyFetch(pCur, &available);
-  }else{
-    zData = (char *)sqlite3BtreeDataFetch(pCur, &available);
-  }
-  assert( zData!=0 );
+  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
+  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
+  assert( pPage->nOverflow==1 );
 
-  if( offset+amt<=available && ((pMem->flags&MEM_Dyn)==0 || pMem->xDel) ){
-    sqlite3VdbeMemRelease(pMem);
-    pMem->z = &zData[offset];
-    pMem->flags = MEM_Blob|MEM_Ephem;
-  }else if( SQLITE_OK==(rc = sqlite3VdbeMemGrow(pMem, amt+2, 0)) ){
-    pMem->flags = MEM_Blob|MEM_Dyn|MEM_Term;
-    pMem->enc = 0;
-    pMem->type = SQLITE_BLOB;
-    if( key ){
-      rc = sqlite3BtreeKey(pCur, offset, amt, pMem->z);
-    }else{
-      rc = sqlite3BtreeData(pCur, offset, amt, pMem->z);
-    }
-    pMem->z[amt] = 0;
-    pMem->z[amt+1] = 0;
-    if( rc!=SQLITE_OK ){
-      sqlite3VdbeMemRelease(pMem);
+  if( pPage->nCell<=0 ) return SQLITE_CORRUPT_BKPT;
+
+  /* Allocate a new page. This page will become the right-sibling of 
+  ** pPage. Make the parent page writable, so that the new divider cell
+  ** may be inserted. If both these operations are successful, proceed.
+  */
+  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);
+
+  if( rc==SQLITE_OK ){
+
+    u8 *pOut = &pSpace[4];
+    u8 *pCell = pPage->aOvfl[0].pCell;
+    u16 szCell = cellSizePtr(pPage, pCell);
+    u8 *pStop;
+
+    assert( sqlite3PagerIswriteable(pNew->pDbPage) );
+    assert( pPage->aData[0]==(PTF_INTKEY|PTF_LEAFDATA|PTF_LEAF) );
+    zeroPage(pNew, PTF_INTKEY|PTF_LEAFDATA|PTF_LEAF);
+    assemblePage(pNew, 1, &pCell, &szCell);
+
+    /* If this is an auto-vacuum database, update the pointer map
+    ** with entries for the new page, and any pointer from the 
+    ** cell on the page to an overflow page. If either of these
+    ** operations fails, the return code is set, but the contents
+    ** of the parent page are still manipulated by thh code below.
+    ** That is Ok, at this point the parent page is guaranteed to
+    ** be marked as dirty. Returning an error code will cause a
+    ** rollback, undoing any changes made to the parent page.
+    */
+    if( ISAUTOVACUUM ){
+      ptrmapPut(pBt, pgnoNew, PTRMAP_BTREE, pParent->pgno, &rc);
+      if( szCell>pNew->minLocal ){
+        ptrmapPutOvflPtr(pNew, pCell, &rc);
+      }
     }
+  
+    /* Create a divider cell to insert into pParent. The divider cell
+    ** consists of a 4-byte page number (the page number of pPage) and
+    ** a variable length key value (which must be the same value as the
+    ** largest key on pPage).
+    **
+    ** To find the largest key value on pPage, first find the right-most 
+    ** cell on pPage. The first two fields of this cell are the 
+    ** record-length (a variable length integer at most 32-bits in size)
+    ** and the key value (a variable length integer, may have any value).
+    ** The first of the while(...) loops below skips over the record-length
+    ** field. The second while(...) loop copies the key value from the
+    ** cell on pPage into the pSpace buffer.
+    */
+    pCell = findCell(pPage, pPage->nCell-1);
+    pStop = &pCell[9];
+    while( (*(pCell++)&0x80) && pCell<pStop );
+    pStop = &pCell[9];
+    while( ((*(pOut++) = *(pCell++))&0x80) && pCell<pStop );
+
+    /* Insert the new divider cell into pParent. */
+    insertCell(pParent, pParent->nCell, pSpace, (int)(pOut-pSpace),
+               0, pPage->pgno, &rc);
+
+    /* Set the right-child pointer of pParent to point to the new page. */
+    put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew);
+  
+    /* Release the reference to the new page. */
+    releasePage(pNew);
   }
-  pMem->n = amt;
 
   return rc;
 }
+#endif /* SQLITE_OMIT_QUICKBALANCE */
 
 #if 0
 /*
-** Perform various checks on the memory cell pMem. An assert() will
-** fail if pMem is internally inconsistent.
+** This function does not contribute anything to the operation of SQLite.
+** it is sometimes activated temporarily while debugging code responsible 
+** for setting pointer-map entries.
 */
-SQLITE_PRIVATE void sqlite3VdbeMemSanity(Mem *pMem){
-  int flags = pMem->flags;
-  assert( flags!=0 );  /* Must define some type */
-  if( flags & (MEM_Str|MEM_Blob) ){
-    int x = flags & (MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short);
-    assert( x!=0 );            /* Strings must define a string subtype */
-    assert( (x & (x-1))==0 );  /* Only one string subtype can be defined */
-    assert( pMem->z!=0 );      /* Strings must have a value */
-    /* Mem.z points to Mem.zShort iff the subtype is MEM_Short */
-    assert( (x & MEM_Short)==0 || pMem->z==pMem->zShort );
-    assert( (x & MEM_Short)!=0 || pMem->z!=pMem->zShort );
-    /* No destructor unless there is MEM_Dyn */
-    assert( pMem->xDel==0 || (pMem->flags & MEM_Dyn)!=0 );
-
-    if( (flags & MEM_Str) ){
-      assert( pMem->enc==SQLITE_UTF8 || 
-              pMem->enc==SQLITE_UTF16BE ||
-              pMem->enc==SQLITE_UTF16LE 
-      );
-      /* If the string is UTF-8 encoded and nul terminated, then pMem->n
-      ** must be the length of the string.  (Later:)  If the database file
-      ** has been corrupted, '\000' characters might have been inserted
-      ** into the middle of the string.  In that case, the strlen() might
-      ** be less.
-      */
-      if( pMem->enc==SQLITE_UTF8 && (flags & MEM_Term) ){ 
-        assert( strlen(pMem->z)<=pMem->n );
-        assert( pMem->z[pMem->n]==0 );
+static int ptrmapCheckPages(MemPage **apPage, int nPage){
+  int i, j;
+  for(i=0; i<nPage; i++){
+    Pgno n;
+    u8 e;
+    MemPage *pPage = apPage[i];
+    BtShared *pBt = pPage->pBt;
+    assert( pPage->isInit );
+
+    for(j=0; j<pPage->nCell; j++){
+      CellInfo info;
+      u8 *z;
+     
+      z = findCell(pPage, j);
+      btreeParseCellPtr(pPage, z, &info);
+      if( info.iOverflow ){
+        Pgno ovfl = get4byte(&z[info.iOverflow]);
+        ptrmapGet(pBt, ovfl, &e, &n);
+        assert( n==pPage->pgno && e==PTRMAP_OVERFLOW1 );
+      }
+      if( !pPage->leaf ){
+        Pgno child = get4byte(z);
+        ptrmapGet(pBt, child, &e, &n);
+        assert( n==pPage->pgno && e==PTRMAP_BTREE );
       }
     }
-  }else{
-    /* Cannot define a string subtype for non-string objects */
-    assert( (pMem->flags & (MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short))==0 );
-    assert( pMem->xDel==0 );
+    if( !pPage->leaf ){
+      Pgno child = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+      ptrmapGet(pBt, child, &e, &n);
+      assert( n==pPage->pgno && e==PTRMAP_BTREE );
+    }
   }
-  /* MEM_Null excludes all other types */
-  assert( (pMem->flags&(MEM_Str|MEM_Int|MEM_Real|MEM_Blob))==0
-          || (pMem->flags&MEM_Null)==0 );
-  /* If the MEM is both real and integer, the values are equal */
-  assert( (pMem->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) 
-          || pMem->r==pMem->u.i );
+  return 1;
 }
 #endif
 
-/* This function is only available internally, it is not part of the
-** external API. It works in a similar way to sqlite3_value_text(),
-** except the data returned is in the encoding specified by the second
-** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or
-** SQLITE_UTF8.
+/*
+** This function is used to copy the contents of the b-tree node stored 
+** on page pFrom to page pTo. If page pFrom was not a leaf page, then
+** the pointer-map entries for each child page are updated so that the
+** parent page stored in the pointer map is page pTo. If pFrom contained
+** any cells with overflow page pointers, then the corresponding pointer
+** map entries are also updated so that the parent page is page pTo.
 **
-** (2006-02-16:)  The enc value can be or-ed with SQLITE_UTF16_ALIGNED.
-** If that is the case, then the result must be aligned on an even byte
-** boundary.
+** If pFrom is currently carrying any overflow cells (entries in the
+** MemPage.aOvfl[] array), they are not copied to pTo. 
+**
+** Before returning, page pTo is reinitialized using btreeInitPage().
+**
+** The performance of this function is not critical. It is only used by 
+** the balance_shallower() and balance_deeper() procedures, neither of
+** which are called often under normal circumstances.
 */
-SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){
-  if( !pVal ) return 0;
+static void copyNodeContent(MemPage *pFrom, MemPage *pTo, int *pRC){
+  if( (*pRC)==SQLITE_OK ){
+    BtShared * const pBt = pFrom->pBt;
+    u8 * const aFrom = pFrom->aData;
+    u8 * const aTo = pTo->aData;
+    int const iFromHdr = pFrom->hdrOffset;
+    int const iToHdr = ((pTo->pgno==1) ? 100 : 0);
+    TESTONLY(int rc;)
+    int iData;
+  
+  
+    assert( pFrom->isInit );
+    assert( pFrom->nFree>=iToHdr );
+    assert( get2byte(&aFrom[iFromHdr+5])<=pBt->usableSize );
+  
+    /* Copy the b-tree node content from page pFrom to page pTo. */
+    iData = get2byte(&aFrom[iFromHdr+5]);
+    memcpy(&aTo[iData], &aFrom[iData], pBt->usableSize-iData);
+    memcpy(&aTo[iToHdr], &aFrom[iFromHdr], pFrom->cellOffset + 2*pFrom->nCell);
+  
+    /* Reinitialize page pTo so that the contents of the MemPage structure
+    ** match the new data. The initialization of pTo "cannot" fail, as the
+    ** data copied from pFrom is known to be valid.  */
+    pTo->isInit = 0;
+    TESTONLY(rc = ) btreeInitPage(pTo);
+    assert( rc==SQLITE_OK );
+  
+    /* If this is an auto-vacuum database, update the pointer-map entries
+    ** for any b-tree or overflow pages that pTo now contains the pointers to.
+    */
+    if( ISAUTOVACUUM ){
+      *pRC = setChildPtrmaps(pTo);
+    }
+  }
+}
 
-  assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
-  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
+/*
+** This routine redistributes cells on the iParentIdx'th child of pParent
+** (hereafter "the page") and up to 2 siblings so that all pages have about the
+** same amount of free space. Usually a single sibling on either side of the
+** page are used in the balancing, though both siblings might come from one
+** side if the page is the first or last child of its parent. If the page 
+** has fewer than 2 siblings (something which can only happen if the page
+** is a root page or a child of a root page) then all available siblings
+** participate in the balancing.
+**
+** The number of siblings of the page might be increased or decreased by 
+** one or two in an effort to keep pages nearly full but not over full. 
+**
+** Note that when this routine is called, some of the cells on the page
+** might not actually be stored in MemPage.aData[]. This can happen
+** if the page is overfull. This routine ensures that all cells allocated
+** to the page and its siblings fit into MemPage.aData[] before returning.
+**
+** In the course of balancing the page and its siblings, cells may be
+** inserted into or removed from the parent page (pParent). Doing so
+** may cause the parent page to become overfull or underfull. If this
+** happens, it is the responsibility of the caller to invoke the correct
+** balancing routine to fix this problem (see the balance() routine). 
+**
+** If this routine fails for any reason, it might leave the database
+** in a corrupted state. So if this routine fails, the database should
+** be rolled back.
+**
+** The third argument to this function, aOvflSpace, is a pointer to a
+** buffer big enough to hold one page. If while inserting cells into the parent
+** page (pParent) the parent page becomes overfull, this buffer is
+** used to store the parent's overflow cells. Because this function inserts
+** a maximum of four divider cells into the parent page, and the maximum
+** size of a cell stored within an internal node is always less than 1/4
+** of the page-size, the aOvflSpace[] buffer is guaranteed to be large
+** enough for all overflow cells.
+**
+** If aOvflSpace is set to a null pointer, this function returns 
+** SQLITE_NOMEM.
+*/
+static int balance_nonroot(
+  MemPage *pParent,               /* Parent page of siblings being balanced */
+  int iParentIdx,                 /* Index of "the page" in pParent */
+  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
+  int isRoot                      /* True if pParent is a root-page */
+){
+  BtShared *pBt;               /* The whole database */
+  int nCell = 0;               /* Number of cells in apCell[] */
+  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
+  int nNew = 0;                /* Number of pages in apNew[] */
+  int nOld;                    /* Number of pages in apOld[] */
+  int i, j, k;                 /* Loop counters */
+  int nxDiv;                   /* Next divider slot in pParent->aCell[] */
+  int rc = SQLITE_OK;          /* The return code */
+  u16 leafCorrection;          /* 4 if pPage is a leaf.  0 if not */
+  int leafData;                /* True if pPage is a leaf of a LEAFDATA tree */
+  int usableSpace;             /* Bytes in pPage beyond the header */
+  int pageFlags;               /* Value of pPage->aData[0] */
+  int subtotal;                /* Subtotal of bytes in cells on one page */
+  int iSpace1 = 0;             /* First unused byte of aSpace1[] */
+  int iOvflSpace = 0;          /* First unused byte of aOvflSpace[] */
+  int szScratch;               /* Size of scratch memory requested */
+  MemPage *apOld[NB];          /* pPage and up to two siblings */
+  MemPage *apCopy[NB];         /* Private copies of apOld[] pages */
+  MemPage *apNew[NB+2];        /* pPage and up to NB siblings after balancing */
+  u8 *pRight;                  /* Location in parent of right-sibling pointer */
+  u8 *apDiv[NB-1];             /* Divider cells in pParent */
+  int cntNew[NB+2];            /* Index in aCell[] of cell after i-th page */
+  int szNew[NB+2];             /* Combined size of cells place on i-th page */
+  u8 **apCell = 0;             /* All cells begin balanced */
+  u16 *szCell;                 /* Local size of all cells in apCell[] */
+  u8 *aSpace1;                 /* Space for copies of dividers cells */
+  Pgno pgno;                   /* Temp var to store a page number in */
 
-  if( pVal->flags&MEM_Null ){
-    return 0;
+  pBt = pParent->pBt;
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
+
+#if 0
+  TRACE(("BALANCE: begin page %d child of %d\n", pPage->pgno, pParent->pgno));
+#endif
+
+  /* At this point pParent may have at most one overflow cell. And if
+  ** this overflow cell is present, it must be the cell with 
+  ** index iParentIdx. This scenario comes about when this function
+  ** is called (indirectly) from sqlite3BtreeDelete().
+  */
+  assert( pParent->nOverflow==0 || pParent->nOverflow==1 );
+  assert( pParent->nOverflow==0 || pParent->aOvfl[0].idx==iParentIdx );
+
+  if( !aOvflSpace ){
+    return SQLITE_NOMEM;
   }
-  assert( (MEM_Blob>>3) == MEM_Str );
-  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
-  expandBlob(pVal);
-  if( pVal->flags&MEM_Str ){
-    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
-    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&(int)pVal->z) ){
-      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
-      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
-        return 0;
-      }
-    }
-    sqlite3VdbeMemNulTerminate(pVal);
+
+  /* Find the sibling pages to balance. Also locate the cells in pParent 
+  ** that divide the siblings. An attempt is made to find NN siblings on 
+  ** either side of pPage. More siblings are taken from one side, however, 
+  ** if there are fewer than NN siblings on the other side. If pParent
+  ** has NB or fewer children then all children of pParent are taken.  
+  **
+  ** This loop also drops the divider cells from the parent page. This
+  ** way, the remainder of the function does not have to deal with any
+  ** overflow cells in the parent page, since if any existed they will
+  ** have already been removed.
+  */
+  i = pParent->nOverflow + pParent->nCell;
+  if( i<2 ){
+    nxDiv = 0;
+    nOld = i+1;
   }else{
-    assert( (pVal->flags&MEM_Blob)==0 );
-    sqlite3VdbeMemStringify(pVal, enc);
-    assert( 0==(1&(int)pVal->z) );
+    nOld = 3;
+    if( iParentIdx==0 ){                 
+      nxDiv = 0;
+    }else if( iParentIdx==i ){
+      nxDiv = i-2;
+    }else{
+      nxDiv = iParentIdx-1;
+    }
+    i = 2;
   }
-  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
-              || pVal->db->mallocFailed );
-  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
-    return pVal->z;
+  if( (i+nxDiv-pParent->nOverflow)==pParent->nCell ){
+    pRight = &pParent->aData[pParent->hdrOffset+8];
   }else{
-    return 0;
+    pRight = findCell(pParent, i+nxDiv-pParent->nOverflow);
   }
-}
+  pgno = get4byte(pRight);
+  while( 1 ){
+    rc = getAndInitPage(pBt, pgno, &apOld[i]);
+    if( rc ){
+      memset(apOld, 0, (i+1)*sizeof(MemPage*));
+      goto balance_cleanup;
+    }
+    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
+    if( (i--)==0 ) break;
 
-/*
-** Create a new sqlite3_value object.
-*/
-SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *db){
-  Mem *p = sqlite3DbMallocZero(db, sizeof(*p));
-  if( p ){
-    p->flags = MEM_Null;
-    p->type = SQLITE_NULL;
-    p->db = db;
+    if( i+nxDiv==pParent->aOvfl[0].idx && pParent->nOverflow ){
+      apDiv[i] = pParent->aOvfl[0].pCell;
+      pgno = get4byte(apDiv[i]);
+      szNew[i] = cellSizePtr(pParent, apDiv[i]);
+      pParent->nOverflow = 0;
+    }else{
+      apDiv[i] = findCell(pParent, i+nxDiv-pParent->nOverflow);
+      pgno = get4byte(apDiv[i]);
+      szNew[i] = cellSizePtr(pParent, apDiv[i]);
+
+      /* Drop the cell from the parent page. apDiv[i] still points to
+      ** the cell within the parent, even though it has been dropped.
+      ** This is safe because dropping a cell only overwrites the first
+      ** four bytes of it, and this function does not need the first
+      ** four bytes of the divider cell. So the pointer is safe to use
+      ** later on.  
+      **
+      ** Unless SQLite is compiled in secure-delete mode. In this case,
+      ** the dropCell() routine will overwrite the entire cell with zeroes.
+      ** In this case, temporarily copy the cell into the aOvflSpace[]
+      ** buffer. It will be copied out again as soon as the aSpace[] buffer
+      ** is allocated.  */
+#ifdef SQLITE_SECURE_DELETE
+      memcpy(&aOvflSpace[apDiv[i]-pParent->aData], apDiv[i], szNew[i]);
+      apDiv[i] = &aOvflSpace[apDiv[i]-pParent->aData];
+#endif
+      dropCell(pParent, i+nxDiv-pParent->nOverflow, szNew[i], &rc);
+    }
   }
-  return p;
-}
 
-/*
-** Create a new sqlite3_value object, containing the value of pExpr.
-**
-** This only works for very simple expressions that consist of one constant
-** token (i.e. "5", "5.1", "'a string'"). If the expression can
-** be converted directly into a value, then the value is allocated and
-** a pointer written to *ppVal. The caller is responsible for deallocating
-** the value by passing it to sqlite3ValueFree() later on. If the expression
-** cannot be converted to a value, then *ppVal is set to NULL.
-*/
-SQLITE_PRIVATE int sqlite3ValueFromExpr(
-  sqlite3 *db,              /* The database connection */
-  Expr *pExpr,              /* The expression to evaluate */
-  u8 enc,                   /* Encoding to use */
-  u8 affinity,              /* Affinity to use */
-  sqlite3_value **ppVal     /* Write the new value here */
-){
-  int op;
-  char *zVal = 0;
-  sqlite3_value *pVal = 0;
+  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte
+  ** alignment */
+  nMaxCells = (nMaxCells + 3)&~3;
 
-  if( !pExpr ){
-    *ppVal = 0;
-    return SQLITE_OK;
+  /*
+  ** Allocate space for memory structures
+  */
+  k = pBt->pageSize + ROUND8(sizeof(MemPage));
+  szScratch =
+       nMaxCells*sizeof(u8*)                       /* apCell */
+     + nMaxCells*sizeof(u16)                       /* szCell */
+     + pBt->pageSize                               /* aSpace1 */
+     + k*nOld;                                     /* Page copies (apCopy) */
+  apCell = sqlite3ScratchMalloc( szScratch ); 
+  if( apCell==0 ){
+    rc = SQLITE_NOMEM;
+    goto balance_cleanup;
   }
-  op = pExpr->op;
+  szCell = (u16*)&apCell[nMaxCells];
+  aSpace1 = (u8*)&szCell[nMaxCells];
+  assert( EIGHT_BYTE_ALIGNMENT(aSpace1) );
 
-  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
-    zVal = sqlite3StrNDup((char*)pExpr->token.z, pExpr->token.n);
-    pVal = sqlite3ValueNew(db);
-    if( !zVal || !pVal ) goto no_mem;
-    sqlite3Dequote(zVal);
-    sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, sqlite3_free);
-    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
-      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, enc);
-    }else{
-      sqlite3ValueApplyAffinity(pVal, affinity, enc);
+  /*
+  ** Load pointers to all cells on sibling pages and the divider cells
+  ** into the local apCell[] array.  Make copies of the divider cells
+  ** into space obtained from aSpace1[] and remove the the divider Cells
+  ** from pParent.
+  **
+  ** If the siblings are on leaf pages, then the child pointers of the
+  ** divider cells are stripped from the cells before they are copied
+  ** into aSpace1[].  In this way, all cells in apCell[] are without
+  ** child pointers.  If siblings are not leaves, then all cell in
+  ** apCell[] include child pointers.  Either way, all cells in apCell[]
+  ** are alike.
+  **
+  ** leafCorrection:  4 if pPage is a leaf.  0 if pPage is not a leaf.
+  **       leafData:  1 if pPage holds key+data and pParent holds only keys.
+  */
+  leafCorrection = apOld[0]->leaf*4;
+  leafData = apOld[0]->hasData;
+  for(i=0; i<nOld; i++){
+    int limit;
+    
+    /* Before doing anything else, take a copy of the i'th original sibling
+    ** The rest of this function will use data from the copies rather
+    ** that the original pages since the original pages will be in the
+    ** process of being overwritten.  */
+    MemPage *pOld = apCopy[i] = (MemPage*)&aSpace1[pBt->pageSize + k*i];
+    memcpy(pOld, apOld[i], sizeof(MemPage));
+    pOld->aData = (void*)&pOld[1];
+    memcpy(pOld->aData, apOld[i]->aData, pBt->pageSize);
+
+    limit = pOld->nCell+pOld->nOverflow;
+    for(j=0; j<limit; j++){
+      assert( nCell<nMaxCells );
+      apCell[nCell] = findOverflowCell(pOld, j);
+      szCell[nCell] = cellSizePtr(pOld, apCell[nCell]);
+      nCell++;
     }
-  }else if( op==TK_UMINUS ) {
-    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) ){
-      pVal->u.i = -1 * pVal->u.i;
-      pVal->r = -1.0 * pVal->r;
+    if( i<nOld-1 && !leafData){
+      u16 sz = (u16)szNew[i];
+      u8 *pTemp;
+      assert( nCell<nMaxCells );
+      szCell[nCell] = sz;
+      pTemp = &aSpace1[iSpace1];
+      iSpace1 += sz;
+      assert( sz<=pBt->pageSize/4 );
+      assert( iSpace1<=pBt->pageSize );
+      memcpy(pTemp, apDiv[i], sz);
+      apCell[nCell] = pTemp+leafCorrection;
+      assert( leafCorrection==0 || leafCorrection==4 );
+      szCell[nCell] = szCell[nCell] - leafCorrection;
+      if( !pOld->leaf ){
+        assert( leafCorrection==0 );
+        assert( pOld->hdrOffset==0 );
+        /* The right pointer of the child page pOld becomes the left
+        ** pointer of the divider cell */
+        memcpy(apCell[nCell], &pOld->aData[8], 4);
+      }else{
+        assert( leafCorrection==4 );
+        if( szCell[nCell]<4 ){
+          /* Do not allow any cells smaller than 4 bytes. */
+          szCell[nCell] = 4;
+        }
+      }
+      nCell++;
     }
   }
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-  else if( op==TK_BLOB ){
-    int nVal;
-    assert( pExpr->token.n>=3 );
-    assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
-    assert( pExpr->token.z[1]=='\'' );
-    assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
-    pVal = sqlite3ValueNew(db);
-    nVal = pExpr->token.n - 3;
-    zVal = (char*)pExpr->token.z + 2;
-    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
-                         0, sqlite3_free);
+
+  /*
+  ** Figure out the number of pages needed to hold all nCell cells.
+  ** Store this number in "k".  Also compute szNew[] which is the total
+  ** size of all cells on the i-th page and cntNew[] which is the index
+  ** in apCell[] of the cell that divides page i from page i+1.  
+  ** cntNew[k] should equal nCell.
+  **
+  ** Values computed by this block:
+  **
+  **           k: The total number of sibling pages
+  **    szNew[i]: Spaced used on the i-th sibling page.
+  **   cntNew[i]: Index in apCell[] and szCell[] for the first cell to
+  **              the right of the i-th sibling page.
+  ** usableSpace: Number of bytes of space available on each sibling.
+  ** 
+  */
+  usableSpace = pBt->usableSize - 12 + leafCorrection;
+  for(subtotal=k=i=0; i<nCell; i++){
+    assert( i<nMaxCells );
+    subtotal += szCell[i] + 2;
+    if( subtotal > usableSpace ){
+      szNew[k] = subtotal - szCell[i];
+      cntNew[k] = i;
+      if( leafData ){ i--; }
+      subtotal = 0;
+      k++;
+      if( k>NB+1 ){ rc = SQLITE_CORRUPT; goto balance_cleanup; }
+    }
   }
-#endif
+  szNew[k] = subtotal;
+  cntNew[k] = nCell;
+  k++;
 
-  *ppVal = pVal;
-  return SQLITE_OK;
+  /*
+  ** The packing computed by the previous block is biased toward the siblings
+  ** on the left side.  The left siblings are always nearly full, while the
+  ** right-most sibling might be nearly empty.  This block of code attempts
+  ** to adjust the packing of siblings to get a better balance.
+  **
+  ** This adjustment is more than an optimization.  The packing above might
+  ** be so out of balance as to be illegal.  For example, the right-most
+  ** sibling might be completely empty.  This adjustment is not optional.
+  */
+  for(i=k-1; i>0; i--){
+    int szRight = szNew[i];  /* Size of sibling on the right */
+    int szLeft = szNew[i-1]; /* Size of sibling on the left */
+    int r;              /* Index of right-most cell in left sibling */
+    int d;              /* Index of first cell to the left of right sibling */
 
-no_mem:
-  db->mallocFailed = 1;
-  sqlite3_free(zVal);
-  sqlite3ValueFree(pVal);
-  *ppVal = 0;
-  return SQLITE_NOMEM;
-}
+    r = cntNew[i-1] - 1;
+    d = r + 1 - leafData;
+    assert( d<nMaxCells );
+    assert( r<nMaxCells );
+    while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){
+      szRight += szCell[d] + 2;
+      szLeft -= szCell[r] + 2;
+      cntNew[i-1]--;
+      r = cntNew[i-1] - 1;
+      d = r + 1 - leafData;
+    }
+    szNew[i] = szRight;
+    szNew[i-1] = szLeft;
+  }
 
-/*
-** Change the string value of an sqlite3_value object
-*/
-SQLITE_PRIVATE void sqlite3ValueSetStr(
-  sqlite3_value *v,     /* Value to be set */
-  int n,                /* Length of string z */
-  const void *z,        /* Text of the new string */
-  u8 enc,               /* Encoding to use */
-  void (*xDel)(void*)   /* Destructor for the string */
-){
-  if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel);
-}
+  /* Either we found one or more cells (cntnew[0])>0) or pPage is
+  ** a virtual root page.  A virtual root page is when the real root
+  ** page is page 1 and we are the only child of that page.
+  */
+  assert( cntNew[0]>0 || (pParent->pgno==1 && pParent->nCell==0) );
 
-/*
-** Free an sqlite3_value object
-*/
-SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value *v){
-  if( !v ) return;
-  sqlite3VdbeMemRelease((Mem *)v);
-  sqlite3_free(v);
-}
+  TRACE(("BALANCE: old: %d %d %d  ",
+    apOld[0]->pgno, 
+    nOld>=2 ? apOld[1]->pgno : 0,
+    nOld>=3 ? apOld[2]->pgno : 0
+  ));
 
-/*
-** Return the number of bytes in the sqlite3_value object assuming
-** that it uses the encoding "enc"
-*/
-SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){
-  Mem *p = (Mem*)pVal;
-  if( (p->flags & MEM_Blob)!=0 || sqlite3ValueText(pVal, enc) ){
-    if( p->flags & MEM_Zero ){
-      return p->n+p->u.i;
+  /*
+  ** Allocate k new pages.  Reuse old pages where possible.
+  */
+  if( apOld[0]->pgno<=1 ){
+    rc = SQLITE_CORRUPT;
+    goto balance_cleanup;
+  }
+  pageFlags = apOld[0]->aData[0];
+  for(i=0; i<k; i++){
+    MemPage *pNew;
+    if( i<nOld ){
+      pNew = apNew[i] = apOld[i];
+      apOld[i] = 0;
+      rc = sqlite3PagerWrite(pNew->pDbPage);
+      nNew++;
+      if( rc ) goto balance_cleanup;
     }else{
-      return p->n;
+      assert( i>0 );
+      rc = allocateBtreePage(pBt, &pNew, &pgno, pgno, 0);
+      if( rc ) goto balance_cleanup;
+      apNew[i] = pNew;
+      nNew++;
+
+      /* Set the pointer-map entry for the new sibling page. */
+      if( ISAUTOVACUUM ){
+        ptrmapPut(pBt, pNew->pgno, PTRMAP_BTREE, pParent->pgno, &rc);
+        if( rc!=SQLITE_OK ){
+          goto balance_cleanup;
+        }
+      }
     }
   }
-  return 0;
+
+  /* Free any old pages that were not reused as new pages.
+  */
+  while( i<nOld ){
+    freePage(apOld[i], &rc);
+    if( rc ) goto balance_cleanup;
+    releasePage(apOld[i]);
+    apOld[i] = 0;
+    i++;
+  }
+
+  /*
+  ** Put the new pages in accending order.  This helps to
+  ** keep entries in the disk file in order so that a scan
+  ** of the table is a linear scan through the file.  That
+  ** in turn helps the operating system to deliver pages
+  ** from the disk more rapidly.
+  **
+  ** An O(n^2) insertion sort algorithm is used, but since
+  ** n is never more than NB (a small constant), that should
+  ** not be a problem.
+  **
+  ** When NB==3, this one optimization makes the database
+  ** about 25% faster for large insertions and deletions.
+  */
+  for(i=0; i<k-1; i++){
+    int minV = apNew[i]->pgno;
+    int minI = i;
+    for(j=i+1; j<k; j++){
+      if( apNew[j]->pgno<(unsigned)minV ){
+        minI = j;
+        minV = apNew[j]->pgno;
+      }
+    }
+    if( minI>i ){
+      int t;
+      MemPage *pT;
+      t = apNew[i]->pgno;
+      pT = apNew[i];
+      apNew[i] = apNew[minI];
+      apNew[minI] = pT;
+    }
+  }
+  TRACE(("new: %d(%d) %d(%d) %d(%d) %d(%d) %d(%d)\n",
+    apNew[0]->pgno, szNew[0],
+    nNew>=2 ? apNew[1]->pgno : 0, nNew>=2 ? szNew[1] : 0,
+    nNew>=3 ? apNew[2]->pgno : 0, nNew>=3 ? szNew[2] : 0,
+    nNew>=4 ? apNew[3]->pgno : 0, nNew>=4 ? szNew[3] : 0,
+    nNew>=5 ? apNew[4]->pgno : 0, nNew>=5 ? szNew[4] : 0));
+
+  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
+  put4byte(pRight, apNew[nNew-1]->pgno);
+
+  /*
+  ** Evenly distribute the data in apCell[] across the new pages.
+  ** Insert divider cells into pParent as necessary.
+  */
+  j = 0;
+  for(i=0; i<nNew; i++){
+    /* Assemble the new sibling page. */
+    MemPage *pNew = apNew[i];
+    assert( j<nMaxCells );
+    zeroPage(pNew, pageFlags);
+    assemblePage(pNew, cntNew[i]-j, &apCell[j], &szCell[j]);
+    assert( pNew->nCell>0 || (nNew==1 && cntNew[0]==0) );
+    assert( pNew->nOverflow==0 );
+
+    j = cntNew[i];
+
+    /* If the sibling page assembled above was not the right-most sibling,
+    ** insert a divider cell into the parent page.
+    */
+    assert( i<nNew-1 || j==nCell );
+    if( j<nCell ){
+      u8 *pCell;
+      u8 *pTemp;
+      int sz;
+
+      assert( j<nMaxCells );
+      pCell = apCell[j];
+      sz = szCell[j] + leafCorrection;
+      pTemp = &aOvflSpace[iOvflSpace];
+      if( !pNew->leaf ){
+        memcpy(&pNew->aData[8], pCell, 4);
+      }else if( leafData ){
+        /* If the tree is a leaf-data tree, and the siblings are leaves, 
+        ** then there is no divider cell in apCell[]. Instead, the divider 
+        ** cell consists of the integer key for the right-most cell of 
+        ** the sibling-page assembled above only.
+        */
+        CellInfo info;
+        j--;
+        btreeParseCellPtr(pNew, apCell[j], &info);
+        pCell = pTemp;
+        sz = 4 + putVarint(&pCell[4], info.nKey);
+        pTemp = 0;
+      }else{
+        pCell -= 4;
+        /* Obscure case for non-leaf-data trees: If the cell at pCell was
+        ** previously stored on a leaf node, and its reported size was 4
+        ** bytes, then it may actually be smaller than this 
+        ** (see btreeParseCellPtr(), 4 bytes is the minimum size of
+        ** any cell). But it is important to pass the correct size to 
+        ** insertCell(), so reparse the cell now.
+        **
+        ** Note that this can never happen in an SQLite data file, as all
+        ** cells are at least 4 bytes. It only happens in b-trees used
+        ** to evaluate "IN (SELECT ...)" and similar clauses.
+        */
+        if( szCell[j]==4 ){
+          assert(leafCorrection==4);
+          sz = cellSizePtr(pParent, pCell);
+        }
+      }
+      iOvflSpace += sz;
+      assert( sz<=pBt->pageSize/4 );
+      assert( iOvflSpace<=pBt->pageSize );
+      insertCell(pParent, nxDiv, pCell, sz, pTemp, pNew->pgno, &rc);
+      if( rc!=SQLITE_OK ) goto balance_cleanup;
+      assert( sqlite3PagerIswriteable(pParent->pDbPage) );
+
+      j++;
+      nxDiv++;
+    }
+  }
+  assert( j==nCell );
+  assert( nOld>0 );
+  assert( nNew>0 );
+  if( (pageFlags & PTF_LEAF)==0 ){
+    u8 *zChild = &apCopy[nOld-1]->aData[8];
+    memcpy(&apNew[nNew-1]->aData[8], zChild, 4);
+  }
+
+  if( isRoot && pParent->nCell==0 && pParent->hdrOffset<=apNew[0]->nFree ){
+    /* The root page of the b-tree now contains no cells. The only sibling
+    ** page is the right-child of the parent. Copy the contents of the
+    ** child page into the parent, decreasing the overall height of the
+    ** b-tree structure by one. This is described as the "balance-shallower"
+    ** sub-algorithm in some documentation.
+    **
+    ** If this is an auto-vacuum database, the call to copyNodeContent() 
+    ** sets all pointer-map entries corresponding to database image pages 
+    ** for which the pointer is stored within the content being copied.
+    **
+    ** The second assert below verifies that the child page is defragmented
+    ** (it must be, as it was just reconstructed using assemblePage()). This
+    ** is important if the parent page happens to be page 1 of the database
+    ** image.  */
+    assert( nNew==1 );
+    assert( apNew[0]->nFree == 
+        (get2byte(&apNew[0]->aData[5])-apNew[0]->cellOffset-apNew[0]->nCell*2) 
+    );
+    copyNodeContent(apNew[0], pParent, &rc);
+    freePage(apNew[0], &rc);
+  }else if( ISAUTOVACUUM ){
+    /* Fix the pointer-map entries for all the cells that were shifted around. 
+    ** There are several different types of pointer-map entries that need to
+    ** be dealt with by this routine. Some of these have been set already, but
+    ** many have not. The following is a summary:
+    **
+    **   1) The entries associated with new sibling pages that were not
+    **      siblings when this function was called. These have already
+    **      been set. We don't need to worry about old siblings that were
+    **      moved to the free-list - the freePage() code has taken care
+    **      of those.
+    **
+    **   2) The pointer-map entries associated with the first overflow
+    **      page in any overflow chains used by new divider cells. These 
+    **      have also already been taken care of by the insertCell() code.
+    **
+    **   3) If the sibling pages are not leaves, then the child pages of
+    **      cells stored on the sibling pages may need to be updated.
+    **
+    **   4) If the sibling pages are not internal intkey nodes, then any
+    **      overflow pages used by these cells may need to be updated
+    **      (internal intkey nodes never contain pointers to overflow pages).
+    **
+    **   5) If the sibling pages are not leaves, then the pointer-map
+    **      entries for the right-child pages of each sibling may need
+    **      to be updated.
+    **
+    ** Cases 1 and 2 are dealt with above by other code. The next
+    ** block deals with cases 3 and 4 and the one after that, case 5. Since
+    ** setting a pointer map entry is a relatively expensive operation, this
+    ** code only sets pointer map entries for child or overflow pages that have
+    ** actually moved between pages.  */
+    MemPage *pNew = apNew[0];
+    MemPage *pOld = apCopy[0];
+    int nOverflow = pOld->nOverflow;
+    int iNextOld = pOld->nCell + nOverflow;
+    int iOverflow = (nOverflow ? pOld->aOvfl[0].idx : -1);
+    j = 0;                             /* Current 'old' sibling page */
+    k = 0;                             /* Current 'new' sibling page */
+    for(i=0; i<nCell; i++){
+      int isDivider = 0;
+      while( i==iNextOld ){
+        /* Cell i is the cell immediately following the last cell on old
+        ** sibling page j. If the siblings are not leaf pages of an
+        ** intkey b-tree, then cell i was a divider cell. */
+        pOld = apCopy[++j];
+        iNextOld = i + !leafData + pOld->nCell + pOld->nOverflow;
+        if( pOld->nOverflow ){
+          nOverflow = pOld->nOverflow;
+          iOverflow = i + !leafData + pOld->aOvfl[0].idx;
+        }
+        isDivider = !leafData;  
+      }
+
+      assert(nOverflow>0 || iOverflow<i );
+      assert(nOverflow<2 || pOld->aOvfl[0].idx==pOld->aOvfl[1].idx-1);
+      assert(nOverflow<3 || pOld->aOvfl[1].idx==pOld->aOvfl[2].idx-1);
+      if( i==iOverflow ){
+        isDivider = 1;
+        if( (--nOverflow)>0 ){
+          iOverflow++;
+        }
+      }
+
+      if( i==cntNew[k] ){
+        /* Cell i is the cell immediately following the last cell on new
+        ** sibling page k. If the siblings are not leaf pages of an
+        ** intkey b-tree, then cell i is a divider cell.  */
+        pNew = apNew[++k];
+        if( !leafData ) continue;
+      }
+      assert( j<nOld );
+      assert( k<nNew );
+
+      /* If the cell was originally divider cell (and is not now) or
+      ** an overflow cell, or if the cell was located on a different sibling
+      ** page before the balancing, then the pointer map entries associated
+      ** with any child or overflow pages need to be updated.  */
+      if( isDivider || pOld->pgno!=pNew->pgno ){
+        if( !leafCorrection ){
+          ptrmapPut(pBt, get4byte(apCell[i]), PTRMAP_BTREE, pNew->pgno, &rc);
+        }
+        if( szCell[i]>pNew->minLocal ){
+          ptrmapPutOvflPtr(pNew, apCell[i], &rc);
+        }
+      }
+    }
+
+    if( !leafCorrection ){
+      for(i=0; i<nNew; i++){
+        u32 key = get4byte(&apNew[i]->aData[8]);
+        ptrmapPut(pBt, key, PTRMAP_BTREE, apNew[i]->pgno, &rc);
+      }
+    }
+
+#if 0
+    /* The ptrmapCheckPages() contains assert() statements that verify that
+    ** all pointer map pages are set correctly. This is helpful while 
+    ** debugging. This is usually disabled because a corrupt database may
+    ** cause an assert() statement to fail.  */
+    ptrmapCheckPages(apNew, nNew);
+    ptrmapCheckPages(&pParent, 1);
+#endif
+  }
+
+  assert( pParent->isInit );
+  TRACE(("BALANCE: finished: old=%d new=%d cells=%d\n",
+          nOld, nNew, nCell));
+
+  /*
+  ** Cleanup before returning.
+  */
+balance_cleanup:
+  sqlite3ScratchFree(apCell);
+  for(i=0; i<nOld; i++){
+    releasePage(apOld[i]);
+  }
+  for(i=0; i<nNew; i++){
+    releasePage(apNew[i]);
+  }
+
+  return rc;
 }
 
-/************** End of vdbemem.c *********************************************/
-/************** Begin file vdbeaux.c *****************************************/
+
 /*
-** 2003 September 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** This function is called when the root page of a b-tree structure is
+** overfull (has one or more overflow pages).
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** A new child page is allocated and the contents of the current root
+** page, including overflow cells, are copied into the child. The root
+** page is then overwritten to make it an empty page with the right-child 
+** pointer pointing to the new page.
 **
-*************************************************************************
-** This file contains code used for creating, destroying, and populating
-** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
-** to version 2.8.7, all this code was combined into the vdbe.c source file.
-** But that file was getting too big so this subroutines were split out.
+** Before returning, all pointer-map entries corresponding to pages 
+** that the new child-page now contains pointers to are updated. The
+** entry corresponding to the new right-child pointer of the root
+** page is also updated.
 **
-** $Id: vdbeaux.c,v 1.383 2008/05/13 13:27:34 drh Exp $
+** If successful, *ppChild is set to contain a reference to the child 
+** page and SQLITE_OK is returned. In this case the caller is required
+** to call releasePage() on *ppChild exactly once. If an error occurs,
+** an error code is returned and *ppChild is set to 0.
 */
+static int balance_deeper(MemPage *pRoot, MemPage **ppChild){
+  int rc;                        /* Return value from subprocedures */
+  MemPage *pChild = 0;           /* Pointer to a new child page */
+  Pgno pgnoChild = 0;            /* Page number of the new child page */
+  BtShared *pBt = pRoot->pBt;    /* The BTree */
 
+  assert( pRoot->nOverflow>0 );
+  assert( sqlite3_mutex_held(pBt->mutex) );
 
+  /* Make pRoot, the root page of the b-tree, writable. Allocate a new 
+  ** page that will become the new right-child of pPage. Copy the contents
+  ** of the node stored on pRoot into the new child page.
+  */
+  rc = sqlite3PagerWrite(pRoot->pDbPage);
+  if( rc==SQLITE_OK ){
+    rc = allocateBtreePage(pBt,&pChild,&pgnoChild,pRoot->pgno,0);
+    copyNodeContent(pRoot, pChild, &rc);
+    if( ISAUTOVACUUM ){
+      ptrmapPut(pBt, pgnoChild, PTRMAP_BTREE, pRoot->pgno, &rc);
+    }
+  }
+  if( rc ){
+    *ppChild = 0;
+    releasePage(pChild);
+    return rc;
+  }
+  assert( sqlite3PagerIswriteable(pChild->pDbPage) );
+  assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
+  assert( pChild->nCell==pRoot->nCell );
 
-/*
-** When debugging the code generator in a symbolic debugger, one can
-** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
-** as they are added to the instruction stream.
-*/
-#ifdef SQLITE_DEBUG
-SQLITE_PRIVATE int sqlite3VdbeAddopTrace = 0;
-#endif
+  TRACE(("BALANCE: copy root %d into %d\n", pRoot->pgno, pChild->pgno));
 
+  /* Copy the overflow cells from pRoot to pChild */
+  memcpy(pChild->aOvfl, pRoot->aOvfl, pRoot->nOverflow*sizeof(pRoot->aOvfl[0]));
+  pChild->nOverflow = pRoot->nOverflow;
 
-/*
-** Create a new virtual database engine.
-*/
-SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(sqlite3 *db){
-  Vdbe *p;
-  p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
-  if( p==0 ) return 0;
-  p->db = db;
-  if( db->pVdbe ){
-    db->pVdbe->pPrev = p;
-  }
-  p->pNext = db->pVdbe;
-  p->pPrev = 0;
-  db->pVdbe = p;
-  p->magic = VDBE_MAGIC_INIT;
-  return p;
+  /* Zero the contents of pRoot. Then install pChild as the right-child. */
+  zeroPage(pRoot, pChild->aData[0] & ~PTF_LEAF);
+  put4byte(&pRoot->aData[pRoot->hdrOffset+8], pgnoChild);
+
+  *ppChild = pChild;
+  return SQLITE_OK;
 }
 
 /*
-** Remember the SQL string for a prepared statement.
+** The page that pCur currently points to has just been modified in
+** some way. This function figures out if this modification means the
+** tree needs to be balanced, and if so calls the appropriate balancing 
+** routine. Balancing routines are:
+**
+**   balance_quick()
+**   balance_deeper()
+**   balance_nonroot()
 */
-SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n){
-  if( p==0 ) return;
-  assert( p->zSql==0 );
-  p->zSql = sqlite3DbStrNDup(p->db, z, n);
-}
+static int balance(BtCursor *pCur){
+  int rc = SQLITE_OK;
+  const int nMin = pCur->pBt->usableSize * 2 / 3;
+  u8 aBalanceQuickSpace[13];
+  u8 *pFree = 0;
 
-/*
-** Return the SQL associated with a prepared statement
-*/
-SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt){
-  return ((Vdbe *)pStmt)->zSql;
-}
+  TESTONLY( int balance_quick_called = 0 );
+  TESTONLY( int balance_deeper_called = 0 );
 
-/*
-** Swap all content between two VDBE structures.
-*/
-SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
-  Vdbe tmp, *pTmp;
-  char *zTmp;
-  int nTmp;
-  tmp = *pA;
-  *pA = *pB;
-  *pB = tmp;
-  pTmp = pA->pNext;
-  pA->pNext = pB->pNext;
-  pB->pNext = pTmp;
-  pTmp = pA->pPrev;
-  pA->pPrev = pB->pPrev;
-  pB->pPrev = pTmp;
-  zTmp = pA->zSql;
-  pA->zSql = pB->zSql;
-  pB->zSql = zTmp;
-  nTmp = pA->nSql;
-  pA->nSql = pB->nSql;
-  pB->nSql = nTmp;
-}
+  do {
+    int iPage = pCur->iPage;
+    MemPage *pPage = pCur->apPage[iPage];
+
+    if( iPage==0 ){
+      if( pPage->nOverflow ){
+        /* The root page of the b-tree is overfull. In this case call the
+        ** balance_deeper() function to create a new child for the root-page
+        ** and copy the current contents of the root-page to it. The
+        ** next iteration of the do-loop will balance the child page.
+        */ 
+        assert( (balance_deeper_called++)==0 );
+        rc = balance_deeper(pPage, &pCur->apPage[1]);
+        if( rc==SQLITE_OK ){
+          pCur->iPage = 1;
+          pCur->aiIdx[0] = 0;
+          pCur->aiIdx[1] = 0;
+          assert( pCur->apPage[1]->nOverflow );
+        }
+      }else{
+        break;
+      }
+    }else if( pPage->nOverflow==0 && pPage->nFree<=nMin ){
+      break;
+    }else{
+      MemPage * const pParent = pCur->apPage[iPage-1];
+      int const iIdx = pCur->aiIdx[iPage-1];
 
-#ifdef SQLITE_DEBUG
-/*
-** Turn tracing on or off
-*/
-SQLITE_PRIVATE void sqlite3VdbeTrace(Vdbe *p, FILE *trace){
-  p->trace = trace;
-}
+      rc = sqlite3PagerWrite(pParent->pDbPage);
+      if( rc==SQLITE_OK ){
+#ifndef SQLITE_OMIT_QUICKBALANCE
+        if( pPage->hasData
+         && pPage->nOverflow==1
+         && pPage->aOvfl[0].idx==pPage->nCell
+         && pParent->pgno!=1
+         && pParent->nCell==iIdx
+        ){
+          /* Call balance_quick() to create a new sibling of pPage on which
+          ** to store the overflow cell. balance_quick() inserts a new cell
+          ** into pParent, which may cause pParent overflow. If this
+          ** happens, the next interation of the do-loop will balance pParent 
+          ** use either balance_nonroot() or balance_deeper(). Until this
+          ** happens, the overflow cell is stored in the aBalanceQuickSpace[]
+          ** buffer. 
+          **
+          ** The purpose of the following assert() is to check that only a
+          ** single call to balance_quick() is made for each call to this
+          ** function. If this were not verified, a subtle bug involving reuse
+          ** of the aBalanceQuickSpace[] might sneak in.
+          */
+          assert( (balance_quick_called++)==0 );
+          rc = balance_quick(pParent, pPage, aBalanceQuickSpace);
+        }else
 #endif
+        {
+          /* In this case, call balance_nonroot() to redistribute cells
+          ** between pPage and up to 2 of its sibling pages. This involves
+          ** modifying the contents of pParent, which may cause pParent to
+          ** become overfull or underfull. The next iteration of the do-loop
+          ** will balance the parent page to correct this.
+          ** 
+          ** If the parent page becomes overfull, the overflow cell or cells
+          ** are stored in the pSpace buffer allocated immediately below. 
+          ** A subsequent iteration of the do-loop will deal with this by
+          ** calling balance_nonroot() (balance_deeper() may be called first,
+          ** but it doesn't deal with overflow cells - just moves them to a
+          ** different page). Once this subsequent call to balance_nonroot() 
+          ** has completed, it is safe to release the pSpace buffer used by
+          ** the previous call, as the overflow cell data will have been 
+          ** copied either into the body of a database page or into the new
+          ** pSpace buffer passed to the latter call to balance_nonroot().
+          */
+          u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
+          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1);
+          if( pFree ){
+            /* If pFree is not NULL, it points to the pSpace buffer used 
+            ** by a previous call to balance_nonroot(). Its contents are
+            ** now stored either on real database pages or within the 
+            ** new pSpace buffer, so it may be safely freed here. */
+            sqlite3PageFree(pFree);
+          }
 
-/*
-** Resize the Vdbe.aOp array so that it contains at least N
-** elements.
-**
-** If an out-of-memory error occurs while resizing the array,
-** Vdbe.aOp and Vdbe.nOpAlloc remain unchanged (this is so that
-** any opcodes already allocated can be correctly deallocated
-** along with the rest of the Vdbe).
-*/
-static void resizeOpArray(Vdbe *p, int N){
-  VdbeOp *pNew;
-  pNew = sqlite3DbRealloc(p->db, p->aOp, N*sizeof(Op));
-  if( pNew ){
-    p->nOpAlloc = N;
-    p->aOp = pNew;
+          /* The pSpace buffer will be freed after the next call to
+          ** balance_nonroot(), or just before this function returns, whichever
+          ** comes first. */
+          pFree = pSpace;
+        }
+      }
+
+      pPage->nOverflow = 0;
+
+      /* The next iteration of the do-loop balances the parent page. */
+      releasePage(pPage);
+      pCur->iPage--;
+    }
+  }while( rc==SQLITE_OK );
+
+  if( pFree ){
+    sqlite3PageFree(pFree);
   }
+  return rc;
 }
 
+
 /*
-** Add a new instruction to the list of instructions current in the
-** VDBE.  Return the address of the new instruction.
-**
-** Parameters:
-**
-**    p               Pointer to the VDBE
+** Insert a new record into the BTree.  The key is given by (pKey,nKey)
+** and the data is given by (pData,nData).  The cursor is used only to
+** define what table the record should be inserted into.  The cursor
+** is left pointing at a random location.
 **
-**    op              The opcode for this instruction
+** For an INTKEY table, only the nKey value of the key is used.  pKey is
+** ignored.  For a ZERODATA table, the pData and nData are both ignored.
 **
-**    p1, p2, p3      Operands
+** If the seekResult parameter is non-zero, then a successful call to
+** MovetoUnpacked() to seek cursor pCur to (pKey, nKey) has already
+** been performed. seekResult is the search result returned (a negative
+** number if pCur points at an entry that is smaller than (pKey, nKey), or
+** a positive value if pCur points at an etry that is larger than 
+** (pKey, nKey)). 
 **
-** Use the sqlite3VdbeResolveLabel() function to fix an address and
-** the sqlite3VdbeChangeP4() function to change the value of the P4
-** operand.
+** If the seekResult parameter is non-zero, then the caller guarantees that
+** cursor pCur is pointing at the existing copy of a row that is to be
+** overwritten.  If the seekResult parameter is 0, then cursor pCur may
+** point to any entry or to no entry at all and so this function has to seek
+** the cursor before the new key can be inserted.
 */
-SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
-  int i;
-  VdbeOp *pOp;
+SQLITE_PRIVATE int sqlite3BtreeInsert(
+  BtCursor *pCur,                /* Insert data into the table of this cursor */
+  const void *pKey, i64 nKey,    /* The key of the new record */
+  const void *pData, int nData,  /* The data of the new record */
+  int nZero,                     /* Number of extra 0 bytes to append to data */
+  int appendBias,                /* True if this is likely an append */
+  int seekResult                 /* Result of prior MovetoUnpacked() call */
+){
+  int rc;
+  int loc = seekResult;          /* -1: before desired location  +1: after */
+  int szNew;
+  int idx;
+  MemPage *pPage;
+  Btree *p = pCur->pBtree;
+  BtShared *pBt = p->pBt;
+  unsigned char *oldCell;
+  unsigned char *newCell = 0;
 
-  i = p->nOp;
-  assert( p->magic==VDBE_MAGIC_INIT );
-  if( p->nOpAlloc<=i ){
-    resizeOpArray(p, p->nOpAlloc ? p->nOpAlloc*2 : 1024/sizeof(Op));
-    if( p->db->mallocFailed ){
-      return 0;
-    }
+  if( pCur->eState==CURSOR_FAULT ){
+    assert( pCur->skipNext!=SQLITE_OK );
+    return pCur->skipNext;
   }
-  p->nOp++;
-  pOp = &p->aOp[i];
-  pOp->opcode = op;
-  pOp->p5 = 0;
-  pOp->p1 = p1;
-  pOp->p2 = p2;
-  pOp->p3 = p3;
-  pOp->p4.p = 0;
-  pOp->p4type = P4_NOTUSED;
-  p->expired = 0;
-#ifdef SQLITE_DEBUG
-  pOp->zComment = 0;
-  if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
-#endif
-#ifdef VDBE_PROFILE
-  pOp->cycles = 0;
-  pOp->cnt = 0;
-#endif
-  return i;
-}
-SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe *p, int op){
-  return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
-}
-SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
-  return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
-}
-SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
-  return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
-}
 
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->wrFlag && pBt->inTransaction==TRANS_WRITE && !pBt->readOnly );
+  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
 
-/*
-** Add an opcode that includes the p4 value as a pointer.
-*/
-SQLITE_PRIVATE int sqlite3VdbeAddOp4(
-  Vdbe *p,            /* Add the opcode to this VM */
-  int op,             /* The new opcode */
-  int p1,             /* The P1 operand */
-  int p2,             /* The P2 operand */
-  int p3,             /* The P3 operand */
-  const char *zP4,    /* The P4 operand */
-  int p4type          /* P4 operand type */
-){
-  int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
-  sqlite3VdbeChangeP4(p, addr, zP4, p4type);
-  return addr;
-}
+  /* Assert that the caller has been consistent. If this cursor was opened
+  ** expecting an index b-tree, then the caller should be inserting blob
+  ** keys with no associated data. If the cursor was opened expecting an
+  ** intkey table, the caller should be inserting integer keys with a
+  ** blob of associated data.  */
+  assert( (pKey==0)==(pCur->pKeyInfo==0) );
 
-/*
-** Create a new symbolic label for an instruction that has yet to be
-** coded.  The symbolic label is really just a negative number.  The
-** label can be used as the P2 value of an operation.  Later, when
-** the label is resolved to a specific address, the VDBE will scan
-** through its operation list and change all values of P2 which match
-** the label into the resolved address.
-**
-** The VDBE knows that a P2 value is a label because labels are
-** always negative and P2 values are suppose to be non-negative.
-** Hence, a negative P2 value is a label that has yet to be resolved.
-**
-** Zero is returned if a malloc() fails.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe *p){
-  int i;
-  i = p->nLabel++;
-  assert( p->magic==VDBE_MAGIC_INIT );
-  if( i>=p->nLabelAlloc ){
-    p->nLabelAlloc = p->nLabelAlloc*2 + 10;
-    p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
-                                    p->nLabelAlloc*sizeof(p->aLabel[0]));
-  }
-  if( p->aLabel ){
-    p->aLabel[i] = -1;
+  /* If this is an insert into a table b-tree, invalidate any incrblob 
+  ** cursors open on the row being replaced (assuming this is a replace
+  ** operation - if it is not, the following is a no-op).  */
+  if( pCur->pKeyInfo==0 ){
+    invalidateIncrblobCursors(p, nKey, 0);
   }
-  return -1-i;
-}
 
-/*
-** Resolve label "x" to be the address of the next instruction to
-** be inserted.  The parameter "x" must have been obtained from
-** a prior call to sqlite3VdbeMakeLabel().
-*/
-SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe *p, int x){
-  int j = -1-x;
-  assert( p->magic==VDBE_MAGIC_INIT );
-  assert( j>=0 && j<p->nLabel );
-  if( p->aLabel ){
-    p->aLabel[j] = p->nOp;
+  /* Save the positions of any other cursors open on this table.
+  **
+  ** In some cases, the call to btreeMoveto() below is a no-op. For
+  ** example, when inserting data into a table with auto-generated integer
+  ** keys, the VDBE layer invokes sqlite3BtreeLast() to figure out the 
+  ** integer key to use. It then calls this function to actually insert the 
+  ** data into the intkey B-Tree. In this case btreeMoveto() recognizes
+  ** that the cursor is already where it needs to be and returns without
+  ** doing any work. To avoid thwarting these optimizations, it is important
+  ** not to clear the cursor here.
+  */
+  rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
+  if( rc ) return rc;
+  if( !loc ){
+    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
+    if( rc ) return rc;
   }
-}
+  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );
 
-/*
-** Loop through the program looking for P2 values that are negative
-** on jump instructions.  Each such value is a label.  Resolve the
-** label by setting the P2 value to its correct non-zero value.
-**
-** This routine is called once after all opcodes have been inserted.
-**
-** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument 
-** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by 
-** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
-**
-** This routine also does the following optimization:  It scans for
-** instructions that might cause a statement rollback.  Such instructions
-** are:
-**
-**   *  OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
-**   *  OP_Destroy
-**   *  OP_VUpdate
-**   *  OP_VRename
-**
-** If no such instruction is found, then every Statement instruction 
-** is changed to a Noop.  In this way, we avoid creating the statement 
-** journal file unnecessarily.
-*/
-static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
-  int i;
-  int nMaxArgs = 0;
-  Op *pOp;
-  int *aLabel = p->aLabel;
-  int doesStatementRollback = 0;
-  int hasStatementBegin = 0;
-  for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
-    u8 opcode = pOp->opcode;
+  pPage = pCur->apPage[pCur->iPage];
+  assert( pPage->intKey || nKey>=0 );
+  assert( pPage->leaf || !pPage->intKey );
 
-    if( opcode==OP_Function ){
-      if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
-    }else if( opcode==OP_AggStep 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-        || opcode==OP_VUpdate
-#endif
-    ){
-      if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
-    }
-    if( opcode==OP_Halt ){
-      if( pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort ){
-        doesStatementRollback = 1;
-      }
-    }else if( opcode==OP_Statement ){
-      hasStatementBegin = 1;
-    }else if( opcode==OP_Destroy ){
-      doesStatementRollback = 1;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    }else if( opcode==OP_VUpdate || opcode==OP_VRename ){
-      doesStatementRollback = 1;
-    }else if( opcode==OP_VFilter ){
-      int n;
-      assert( p->nOp - i >= 3 );
-      assert( pOp[-1].opcode==OP_Integer );
-      n = pOp[-1].p1;
-      if( n>nMaxArgs ) nMaxArgs = n;
-#endif
+  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
+          pCur->pgnoRoot, nKey, nData, pPage->pgno,
+          loc==0 ? "overwrite" : "new entry"));
+  assert( pPage->isInit );
+  allocateTempSpace(pBt);
+  newCell = pBt->pTmpSpace;
+  if( newCell==0 ) return SQLITE_NOMEM;
+  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
+  if( rc ) goto end_insert;
+  assert( szNew==cellSizePtr(pPage, newCell) );
+  assert( szNew<=MX_CELL_SIZE(pBt) );
+  idx = pCur->aiIdx[pCur->iPage];
+  if( loc==0 ){
+    u16 szOld;
+    assert( idx<pPage->nCell );
+    rc = sqlite3PagerWrite(pPage->pDbPage);
+    if( rc ){
+      goto end_insert;
     }
-
-    if( sqlite3VdbeOpcodeHasProperty(opcode, OPFLG_JUMP) && pOp->p2<0 ){
-      assert( -1-pOp->p2<p->nLabel );
-      pOp->p2 = aLabel[-1-pOp->p2];
+    oldCell = findCell(pPage, idx);
+    if( !pPage->leaf ){
+      memcpy(newCell, oldCell, 4);
     }
+    szOld = cellSizePtr(pPage, oldCell);
+    rc = clearCell(pPage, oldCell);
+    dropCell(pPage, idx, szOld, &rc);
+    if( rc ) goto end_insert;
+  }else if( loc<0 && pPage->nCell>0 ){
+    assert( pPage->leaf );
+    idx = ++pCur->aiIdx[pCur->iPage];
+  }else{
+    assert( pPage->leaf );
   }
-  sqlite3_free(p->aLabel);
-  p->aLabel = 0;
-
-  *pMaxFuncArgs = nMaxArgs;
+  insertCell(pPage, idx, newCell, szNew, 0, 0, &rc);
+  assert( rc!=SQLITE_OK || pPage->nCell>0 || pPage->nOverflow>0 );
 
-  /* If we never rollback a statement transaction, then statement
-  ** transactions are not needed.  So change every OP_Statement
-  ** opcode into an OP_Noop.  This avoid a call to sqlite3OsOpenExclusive()
-  ** which can be expensive on some platforms.
+  /* If no error has occured and pPage has an overflow cell, call balance() 
+  ** to redistribute the cells within the tree. Since balance() may move
+  ** the cursor, zero the BtCursor.info.nSize and BtCursor.validNKey
+  ** variables.
+  **
+  ** Previous versions of SQLite called moveToRoot() to move the cursor
+  ** back to the root page as balance() used to invalidate the contents
+  ** of BtCursor.apPage[] and BtCursor.aiIdx[]. Instead of doing that,
+  ** set the cursor state to "invalid". This makes common insert operations
+  ** slightly faster.
+  **
+  ** There is a subtle but important optimization here too. When inserting
+  ** multiple records into an intkey b-tree using a single cursor (as can
+  ** happen while processing an "INSERT INTO ... SELECT" statement), it
+  ** is advantageous to leave the cursor pointing to the last entry in
+  ** the b-tree if possible. If the cursor is left pointing to the last
+  ** entry in the table, and the next row inserted has an integer key
+  ** larger than the largest existing key, it is possible to insert the
+  ** row without seeking the cursor. This can be a big performance boost.
   */
-  if( hasStatementBegin && !doesStatementRollback ){
-    for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
-      if( pOp->opcode==OP_Statement ){
-        pOp->opcode = OP_Noop;
-      }
-    }
+  pCur->info.nSize = 0;
+  pCur->validNKey = 0;
+  if( rc==SQLITE_OK && pPage->nOverflow ){
+    rc = balance(pCur);
+
+    /* Must make sure nOverflow is reset to zero even if the balance()
+    ** fails. Internal data structure corruption will result otherwise. 
+    ** Also, set the cursor state to invalid. This stops saveCursorPosition()
+    ** from trying to save the current position of the cursor.  */
+    pCur->apPage[pCur->iPage]->nOverflow = 0;
+    pCur->eState = CURSOR_INVALID;
   }
-}
+  assert( pCur->apPage[pCur->iPage]->nOverflow==0 );
 
-/*
-** Return the address of the next instruction to be inserted.
-*/
-SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe *p){
-  assert( p->magic==VDBE_MAGIC_INIT );
-  return p->nOp;
+end_insert:
+  return rc;
 }
 
 /*
-** Add a whole list of operations to the operation stack.  Return the
-** address of the first operation added.
+** Delete the entry that the cursor is pointing to.  The cursor
+** is left pointing at a arbitrary location.
 */
-SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
-  int addr;
-  assert( p->magic==VDBE_MAGIC_INIT );
-  if( p->nOp + nOp > p->nOpAlloc ){
-    resizeOpArray(p, p->nOpAlloc ? p->nOpAlloc*2 : 1024/sizeof(Op));
-    assert( p->nOp+nOp<=p->nOpAlloc || p->db->mallocFailed );
-  }
-  if( p->db->mallocFailed ){
-    return 0;
+SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor *pCur){
+  Btree *p = pCur->pBtree;
+  BtShared *pBt = p->pBt;              
+  int rc;                              /* Return code */
+  MemPage *pPage;                      /* Page to delete cell from */
+  unsigned char *pCell;                /* Pointer to cell to delete */
+  int iCellIdx;                        /* Index of cell to delete */
+  int iCellDepth;                      /* Depth of node containing pCell */ 
+
+  assert( cursorHoldsMutex(pCur) );
+  assert( pBt->inTransaction==TRANS_WRITE );
+  assert( !pBt->readOnly );
+  assert( pCur->wrFlag );
+  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
+  assert( !hasReadConflicts(p, pCur->pgnoRoot) );
+
+  if( NEVER(pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell) 
+   || NEVER(pCur->eState!=CURSOR_VALID)
+  ){
+    return SQLITE_ERROR;  /* Something has gone awry. */
   }
-  addr = p->nOp;
-  if( nOp>0 ){
-    int i;
-    VdbeOpList const *pIn = aOp;
-    for(i=0; i<nOp; i++, pIn++){
-      int p2 = pIn->p2;
-      VdbeOp *pOut = &p->aOp[i+addr];
-      pOut->opcode = pIn->opcode;
-      pOut->p1 = pIn->p1;
-      if( p2<0 && sqlite3VdbeOpcodeHasProperty(pOut->opcode, OPFLG_JUMP) ){
-        pOut->p2 = addr + ADDR(p2);
-      }else{
-        pOut->p2 = p2;
-      }
-      pOut->p3 = pIn->p3;
-      pOut->p4type = P4_NOTUSED;
-      pOut->p4.p = 0;
-      pOut->p5 = 0;
-#ifdef SQLITE_DEBUG
-      pOut->zComment = 0;
-      if( sqlite3VdbeAddopTrace ){
-        sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
-      }
-#endif
-    }
-    p->nOp += nOp;
+
+  /* If this is a delete operation to remove a row from a table b-tree,
+  ** invalidate any incrblob cursors open on the row being deleted.  */
+  if( pCur->pKeyInfo==0 ){
+    invalidateIncrblobCursors(p, pCur->info.nKey, 0);
   }
-  return addr;
-}
 
-/*
-** Change the value of the P1 operand for a specific instruction.
-** This routine is useful when a large program is loaded from a
-** static array using sqlite3VdbeAddOpList but we want to make a
-** few minor changes to the program.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
-  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
-  if( p && addr>=0 && p->nOp>addr && p->aOp ){
-    p->aOp[addr].p1 = val;
+  iCellDepth = pCur->iPage;
+  iCellIdx = pCur->aiIdx[iCellDepth];
+  pPage = pCur->apPage[iCellDepth];
+  pCell = findCell(pPage, iCellIdx);
+
+  /* If the page containing the entry to delete is not a leaf page, move
+  ** the cursor to the largest entry in the tree that is smaller than
+  ** the entry being deleted. This cell will replace the cell being deleted
+  ** from the internal node. The 'previous' entry is used for this instead
+  ** of the 'next' entry, as the previous entry is always a part of the
+  ** sub-tree headed by the child page of the cell being deleted. This makes
+  ** balancing the tree following the delete operation easier.  */
+  if( !pPage->leaf ){
+    int notUsed;
+    rc = sqlite3BtreePrevious(pCur, &notUsed);
+    if( rc ) return rc;
   }
-}
 
-/*
-** Change the value of the P2 operand for a specific instruction.
-** This routine is useful for setting a jump destination.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
-  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
-  if( p && addr>=0 && p->nOp>addr && p->aOp ){
-    p->aOp[addr].p2 = val;
+  /* Save the positions of any other cursors open on this table before
+  ** making any modifications. Make the page containing the entry to be 
+  ** deleted writable. Then free any overflow pages associated with the 
+  ** entry and finally remove the cell itself from within the page.  
+  */
+  rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
+  if( rc ) return rc;
+  rc = sqlite3PagerWrite(pPage->pDbPage);
+  if( rc ) return rc;
+  rc = clearCell(pPage, pCell);
+  dropCell(pPage, iCellIdx, cellSizePtr(pPage, pCell), &rc);
+  if( rc ) return rc;
+
+  /* If the cell deleted was not located on a leaf page, then the cursor
+  ** is currently pointing to the largest entry in the sub-tree headed
+  ** by the child-page of the cell that was just deleted from an internal
+  ** node. The cell from the leaf node needs to be moved to the internal
+  ** node to replace the deleted cell.  */
+  if( !pPage->leaf ){
+    MemPage *pLeaf = pCur->apPage[pCur->iPage];
+    int nCell;
+    Pgno n = pCur->apPage[iCellDepth+1]->pgno;
+    unsigned char *pTmp;
+
+    pCell = findCell(pLeaf, pLeaf->nCell-1);
+    nCell = cellSizePtr(pLeaf, pCell);
+    assert( MX_CELL_SIZE(pBt)>=nCell );
+
+    allocateTempSpace(pBt);
+    pTmp = pBt->pTmpSpace;
+
+    rc = sqlite3PagerWrite(pLeaf->pDbPage);
+    insertCell(pPage, iCellIdx, pCell-4, nCell+4, pTmp, n, &rc);
+    dropCell(pLeaf, pLeaf->nCell-1, nCell, &rc);
+    if( rc ) return rc;
   }
-}
 
-/*
-** Change the value of the P3 operand for a specific instruction.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
-  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
-  if( p && addr>=0 && p->nOp>addr && p->aOp ){
-    p->aOp[addr].p3 = val;
+  /* Balance the tree. If the entry deleted was located on a leaf page,
+  ** then the cursor still points to that page. In this case the first
+  ** call to balance() repairs the tree, and the if(...) condition is
+  ** never true.
+  **
+  ** Otherwise, if the entry deleted was on an internal node page, then
+  ** pCur is pointing to the leaf page from which a cell was removed to
+  ** replace the cell deleted from the internal node. This is slightly
+  ** tricky as the leaf node may be underfull, and the internal node may
+  ** be either under or overfull. In this case run the balancing algorithm
+  ** on the leaf node first. If the balance proceeds far enough up the
+  ** tree that we can be sure that any problem in the internal node has
+  ** been corrected, so be it. Otherwise, after balancing the leaf node,
+  ** walk the cursor up the tree to the internal node and balance it as 
+  ** well.  */
+  rc = balance(pCur);
+  if( rc==SQLITE_OK && pCur->iPage>iCellDepth ){
+    while( pCur->iPage>iCellDepth ){
+      releasePage(pCur->apPage[pCur->iPage--]);
+    }
+    rc = balance(pCur);
   }
-}
 
-/*
-** Change the value of the P5 operand for the most recently
-** added operation.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
-  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
-  if( p && p->aOp ){
-    assert( p->nOp>0 );
-    p->aOp[p->nOp-1].p5 = val;
+  if( rc==SQLITE_OK ){
+    moveToRoot(pCur);
   }
+  return rc;
 }
 
 /*
-** Change the P2 operand of instruction addr so that it points to
-** the address of the next instruction to be coded.
+** Create a new BTree table.  Write into *piTable the page
+** number for the root page of the new table.
+**
+** The type of type is determined by the flags parameter.  Only the
+** following values of flags are currently in use.  Other values for
+** flags might not work:
+**
+**     BTREE_INTKEY|BTREE_LEAFDATA     Used for SQL tables with rowid keys
+**     BTREE_ZERODATA                  Used for SQL indices
 */
-SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe *p, int addr){
-  sqlite3VdbeChangeP2(p, addr, p->nOp);
-}
+static int btreeCreateTable(Btree *p, int *piTable, int flags){
+  BtShared *pBt = p->pBt;
+  MemPage *pRoot;
+  Pgno pgnoRoot;
+  int rc;
 
+  assert( sqlite3BtreeHoldsMutex(p) );
+  assert( pBt->inTransaction==TRANS_WRITE );
+  assert( !pBt->readOnly );
 
-/*
-** If the input FuncDef structure is ephemeral, then free it.  If
-** the FuncDef is not ephermal, then do nothing.
-*/
-static void freeEphemeralFunction(FuncDef *pDef){
-  if( pDef && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
-    sqlite3_free(pDef);
+#ifdef SQLITE_OMIT_AUTOVACUUM
+  rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
+  if( rc ){
+    return rc;
   }
-}
+#else
+  if( pBt->autoVacuum ){
+    Pgno pgnoMove;      /* Move a page here to make room for the root-page */
+    MemPage *pPageMove; /* The page to move to. */
 
-/*
-** Delete a P4 value if necessary.
-*/
-static void freeP4(int p4type, void *p3){
-  if( p3 ){
-    switch( p4type ){
-      case P4_REAL:
-      case P4_INT64:
-      case P4_MPRINTF:
-      case P4_DYNAMIC:
-      case P4_KEYINFO:
-      case P4_KEYINFO_HANDOFF: {
-        sqlite3_free(p3);
-        break;
-      }
-      case P4_VDBEFUNC: {
-        VdbeFunc *pVdbeFunc = (VdbeFunc *)p3;
-        freeEphemeralFunction(pVdbeFunc->pFunc);
-        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
-        sqlite3_free(pVdbeFunc);
-        break;
+    /* Creating a new table may probably require moving an existing database
+    ** to make room for the new tables root page. In case this page turns
+    ** out to be an overflow page, delete all overflow page-map caches
+    ** held by open cursors.
+    */
+    invalidateAllOverflowCache(pBt);
+
+    /* Read the value of meta[3] from the database to determine where the
+    ** root page of the new table should go. meta[3] is the largest root-page
+    ** created so far, so the new root-page is (meta[3]+1).
+    */
+    sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &pgnoRoot);
+    pgnoRoot++;
+
+    /* The new root-page may not be allocated on a pointer-map page, or the
+    ** PENDING_BYTE page.
+    */
+    while( pgnoRoot==PTRMAP_PAGENO(pBt, pgnoRoot) ||
+        pgnoRoot==PENDING_BYTE_PAGE(pBt) ){
+      pgnoRoot++;
+    }
+    assert( pgnoRoot>=3 );
+
+    /* Allocate a page. The page that currently resides at pgnoRoot will
+    ** be moved to the allocated page (unless the allocated page happens
+    ** to reside at pgnoRoot).
+    */
+    rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+
+    if( pgnoMove!=pgnoRoot ){
+      /* pgnoRoot is the page that will be used for the root-page of
+      ** the new table (assuming an error did not occur). But we were
+      ** allocated pgnoMove. If required (i.e. if it was not allocated
+      ** by extending the file), the current page at position pgnoMove
+      ** is already journaled.
+      */
+      u8 eType = 0;
+      Pgno iPtrPage = 0;
+
+      releasePage(pPageMove);
+
+      /* Move the page currently at pgnoRoot to pgnoMove. */
+      rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
+      if( rc!=SQLITE_OK ){
+        return rc;
       }
-      case P4_FUNCDEF: {
-        freeEphemeralFunction((FuncDef*)p3);
-        break;
+      rc = ptrmapGet(pBt, pgnoRoot, &eType, &iPtrPage);
+      if( eType==PTRMAP_ROOTPAGE || eType==PTRMAP_FREEPAGE ){
+        rc = SQLITE_CORRUPT_BKPT;
       }
-      case P4_MEM: {
-        sqlite3ValueFree((sqlite3_value*)p3);
-        break;
+      if( rc!=SQLITE_OK ){
+        releasePage(pRoot);
+        return rc;
       }
-    }
-  }
-}
+      assert( eType!=PTRMAP_ROOTPAGE );
+      assert( eType!=PTRMAP_FREEPAGE );
+      rc = relocatePage(pBt, pRoot, eType, iPtrPage, pgnoMove, 0);
+      releasePage(pRoot);
 
+      /* Obtain the page at pgnoRoot */
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+      rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+      rc = sqlite3PagerWrite(pRoot->pDbPage);
+      if( rc!=SQLITE_OK ){
+        releasePage(pRoot);
+        return rc;
+      }
+    }else{
+      pRoot = pPageMove;
+    } 
 
-/*
-** Change N opcodes starting at addr to No-ops.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
-  if( p && p->aOp ){
-    VdbeOp *pOp = &p->aOp[addr];
-    while( N-- ){
-      freeP4(pOp->p4type, pOp->p4.p);
-      memset(pOp, 0, sizeof(pOp[0]));
-      pOp->opcode = OP_Noop;
-      pOp++;
+    /* Update the pointer-map and meta-data with the new root-page number. */
+    ptrmapPut(pBt, pgnoRoot, PTRMAP_ROOTPAGE, 0, &rc);
+    if( rc ){
+      releasePage(pRoot);
+      return rc;
+    }
+    rc = sqlite3BtreeUpdateMeta(p, 4, pgnoRoot);
+    if( rc ){
+      releasePage(pRoot);
+      return rc;
     }
-  }
-}
 
-/*
-** Change the value of the P4 operand for a specific instruction.
-** This routine is useful when a large program is loaded from a
-** static array using sqlite3VdbeAddOpList but we want to make a
-** few minor changes to the program.
-**
-** If n>=0 then the P4 operand is dynamic, meaning that a copy of
-** the string is made into memory obtained from sqlite3_malloc().
-** A value of n==0 means copy bytes of zP4 up to and including the
-** first null byte.  If n>0 then copy n+1 bytes of zP4.
-**
-** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
-** A copy is made of the KeyInfo structure into memory obtained from
-** sqlite3_malloc, to be freed when the Vdbe is finalized.
-** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
-** stored in memory that the caller has obtained from sqlite3_malloc. The 
-** caller should not free the allocation, it will be freed when the Vdbe is
-** finalized.
-** 
-** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
-** to a string or structure that is guaranteed to exist for the lifetime of
-** the Vdbe. In these cases we can just copy the pointer.
-**
-** If addr<0 then change P4 on the most recently inserted instruction.
-*/
-SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
-  Op *pOp;
-  assert( p!=0 );
-  assert( p->magic==VDBE_MAGIC_INIT );
-  if( p->aOp==0 || p->db->mallocFailed ){
-    if (n != P4_KEYINFO) {
-      freeP4(n, (void*)*(char**)&zP4);
-    }
-    return;
-  }
-  assert( addr<p->nOp );
-  if( addr<0 ){
-    addr = p->nOp - 1;
-    if( addr<0 ) return;
-  }
-  pOp = &p->aOp[addr];
-  freeP4(pOp->p4type, pOp->p4.p);
-  pOp->p4.p = 0;
-  if( n==P4_INT32 ){
-    /* Note: this cast is safe, because the origin data point was an int
-    ** that was cast to a (const char *). */
-    pOp->p4.i = (int)zP4;
-    pOp->p4type = n;
-  }else if( zP4==0 ){
-    pOp->p4.p = 0;
-    pOp->p4type = P4_NOTUSED;
-  }else if( n==P4_KEYINFO ){
-    KeyInfo *pKeyInfo;
-    int nField, nByte;
-
-    nField = ((KeyInfo*)zP4)->nField;
-    nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
-    pKeyInfo = sqlite3_malloc( nByte );
-    pOp->p4.pKeyInfo = pKeyInfo;
-    if( pKeyInfo ){
-      memcpy(pKeyInfo, zP4, nByte);
-      /* In the current implementation, P4_KEYINFO is only ever used on
-      ** KeyInfo structures that have no aSortOrder component.  Elements
-      ** with an aSortOrder always use P4_KEYINFO_HANDOFF.  So we do not
-      ** need to bother with duplicating the aSortOrder. */
-      assert( pKeyInfo->aSortOrder==0 );
-#if 0
-      aSortOrder = pKeyInfo->aSortOrder;
-      if( aSortOrder ){
-        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
-        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
-      }
-#endif
-      pOp->p4type = P4_KEYINFO;
-    }else{
-      p->db->mallocFailed = 1;
-      pOp->p4type = P4_NOTUSED;
-    }
-  }else if( n==P4_KEYINFO_HANDOFF ){
-    pOp->p4.p = (void*)zP4;
-    pOp->p4type = P4_KEYINFO;
-  }else if( n<0 ){
-    pOp->p4.p = (void*)zP4;
-    pOp->p4type = n;
   }else{
-    if( n==0 ) n = strlen(zP4);
-    pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
-    pOp->p4type = P4_DYNAMIC;
+    rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
+    if( rc ) return rc;
   }
+#endif
+  assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
+  zeroPage(pRoot, flags | PTF_LEAF);
+  sqlite3PagerUnref(pRoot->pDbPage);
+  *piTable = (int)pgnoRoot;
+  return SQLITE_OK;
+}
+SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree *p, int *piTable, int flags){
+  int rc;
+  sqlite3BtreeEnter(p);
+  rc = btreeCreateTable(p, piTable, flags);
+  sqlite3BtreeLeave(p);
+  return rc;
 }
 
-#ifndef NDEBUG
 /*
-** Change the comment on the the most recently coded instruction.
+** Erase the given database page and all its children.  Return
+** the page to the freelist.
 */
-SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
-  va_list ap;
-  assert( p->nOp>0 || p->aOp==0 );
-  assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
-  if( p->nOp ){
-    char **pz = &p->aOp[p->nOp-1].zComment;
-    va_start(ap, zFormat);
-    sqlite3_free(*pz);
-    *pz = sqlite3VMPrintf(p->db, zFormat, ap);
-    va_end(ap);
+static int clearDatabasePage(
+  BtShared *pBt,           /* The BTree that contains the table */
+  Pgno pgno,            /* Page number to clear */
+  int freePageFlag,     /* Deallocate page if true */
+  int *pnChange
+){
+  MemPage *pPage;
+  int rc;
+  unsigned char *pCell;
+  int i;
+
+  assert( sqlite3_mutex_held(pBt->mutex) );
+  if( pgno>pagerPagecount(pBt) ){
+    return SQLITE_CORRUPT_BKPT;
+  }
+
+  rc = getAndInitPage(pBt, pgno, &pPage);
+  if( rc ) return rc;
+  for(i=0; i<pPage->nCell; i++){
+    pCell = findCell(pPage, i);
+    if( !pPage->leaf ){
+      rc = clearDatabasePage(pBt, get4byte(pCell), 1, pnChange);
+      if( rc ) goto cleardatabasepage_out;
+    }
+    rc = clearCell(pPage, pCell);
+    if( rc ) goto cleardatabasepage_out;
+  }
+  if( !pPage->leaf ){
+    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), 1, pnChange);
+    if( rc ) goto cleardatabasepage_out;
+  }else if( pnChange ){
+    assert( pPage->intKey );
+    *pnChange += pPage->nCell;
+  }
+  if( freePageFlag ){
+    freePage(pPage, &rc);
+  }else if( (rc = sqlite3PagerWrite(pPage->pDbPage))==0 ){
+    zeroPage(pPage, pPage->aData[0] | PTF_LEAF);
   }
+
+cleardatabasepage_out:
+  releasePage(pPage);
+  return rc;
 }
-#endif
 
 /*
-** Return the opcode for a given address.
+** Delete all information from a single table in the database.  iTable is
+** the page number of the root of the table.  After this routine returns,
+** the root page is empty, but still exists.
+**
+** This routine will fail with SQLITE_LOCKED if there are any open
+** read cursors on the table.  Open write cursors are moved to the
+** root of the table.
+**
+** If pnChange is not NULL, then table iTable must be an intkey table. The
+** integer value pointed to by pnChange is incremented by the number of
+** entries in the table.
 */
-SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
-  assert( p->magic==VDBE_MAGIC_INIT );
-  assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
-  return ((addr>=0 && addr<p->nOp)?(&p->aOp[addr]):0);
+SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree *p, int iTable, int *pnChange){
+  int rc;
+  BtShared *pBt = p->pBt;
+  sqlite3BtreeEnter(p);
+  assert( p->inTrans==TRANS_WRITE );
+
+  /* Invalidate all incrblob cursors open on table iTable (assuming iTable
+  ** is the root of a table b-tree - if it is not, the following call is
+  ** a no-op).  */
+  invalidateIncrblobCursors(p, 0, 1);
+
+  rc = saveAllCursors(pBt, (Pgno)iTable, 0);
+  if( SQLITE_OK==rc ){
+    rc = clearDatabasePage(pBt, (Pgno)iTable, 0, pnChange);
+  }
+  sqlite3BtreeLeave(p);
+  return rc;
 }
 
-#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
-     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
 /*
-** Compute a string that describes the P4 parameter for an opcode.
-** Use zTemp for any required temporary buffer space.
+** Erase all information in a table and add the root of the table to
+** the freelist.  Except, the root of the principle table (the one on
+** page 1) is never added to the freelist.
+**
+** This routine will fail with SQLITE_LOCKED if there are any open
+** cursors on the table.
+**
+** If AUTOVACUUM is enabled and the page at iTable is not the last
+** root page in the database file, then the last root page 
+** in the database file is moved into the slot formerly occupied by
+** iTable and that last slot formerly occupied by the last root page
+** is added to the freelist instead of iTable.  In this say, all
+** root pages are kept at the beginning of the database file, which
+** is necessary for AUTOVACUUM to work right.  *piMoved is set to the 
+** page number that used to be the last root page in the file before
+** the move.  If no page gets moved, *piMoved is set to 0.
+** The last root page is recorded in meta[3] and the value of
+** meta[3] is updated by this procedure.
 */
-static char *displayP4(Op *pOp, char *zTemp, int nTemp){
-  char *zP4 = zTemp;
-  assert( nTemp>=20 );
-  switch( pOp->p4type ){
-    case P4_KEYINFO: {
-      int i, j;
-      KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
-      sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
-      i = strlen(zTemp);
-      for(j=0; j<pKeyInfo->nField; j++){
-        CollSeq *pColl = pKeyInfo->aColl[j];
-        if( pColl ){
-          int n = strlen(pColl->zName);
-          if( i+n>nTemp-6 ){
-            memcpy(&zTemp[i],",...",4);
-            break;
-          }
-          zTemp[i++] = ',';
-          if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
-            zTemp[i++] = '-';
-          }
-          memcpy(&zTemp[i], pColl->zName,n+1);
-          i += n;
-        }else if( i+4<nTemp-6 ){
-          memcpy(&zTemp[i],",nil",4);
-          i += 4;
+static int btreeDropTable(Btree *p, Pgno iTable, int *piMoved){
+  int rc;
+  MemPage *pPage = 0;
+  BtShared *pBt = p->pBt;
+
+  assert( sqlite3BtreeHoldsMutex(p) );
+  assert( p->inTrans==TRANS_WRITE );
+
+  /* It is illegal to drop a table if any cursors are open on the
+  ** database. This is because in auto-vacuum mode the backend may
+  ** need to move another root-page to fill a gap left by the deleted
+  ** root page. If an open cursor was using this page a problem would 
+  ** occur.
+  **
+  ** This error is caught long before control reaches this point.
+  */
+  if( NEVER(pBt->pCursor) ){
+    sqlite3ConnectionBlocked(p->db, pBt->pCursor->pBtree->db);
+    return SQLITE_LOCKED_SHAREDCACHE;
+  }
+
+  rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
+  if( rc ) return rc;
+  rc = sqlite3BtreeClearTable(p, iTable, 0);
+  if( rc ){
+    releasePage(pPage);
+    return rc;
+  }
+
+  *piMoved = 0;
+
+  if( iTable>1 ){
+#ifdef SQLITE_OMIT_AUTOVACUUM
+    freePage(pPage, &rc);
+    releasePage(pPage);
+#else
+    if( pBt->autoVacuum ){
+      Pgno maxRootPgno;
+      sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &maxRootPgno);
+
+      if( iTable==maxRootPgno ){
+        /* If the table being dropped is the table with the largest root-page
+        ** number in the database, put the root page on the free list. 
+        */
+        freePage(pPage, &rc);
+        releasePage(pPage);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+      }else{
+        /* The table being dropped does not have the largest root-page
+        ** number in the database. So move the page that does into the 
+        ** gap left by the deleted root-page.
+        */
+        MemPage *pMove;
+        releasePage(pPage);
+        rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable, 0);
+        releasePage(pMove);
+        if( rc!=SQLITE_OK ){
+          return rc;
         }
+        pMove = 0;
+        rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
+        freePage(pMove, &rc);
+        releasePage(pMove);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        *piMoved = maxRootPgno;
       }
-      zTemp[i++] = ')';
-      zTemp[i] = 0;
-      assert( i<nTemp );
-      break;
-    }
-    case P4_COLLSEQ: {
-      CollSeq *pColl = pOp->p4.pColl;
-      sqlite3_snprintf(nTemp, zTemp, "collseq(%.20s)", pColl->zName);
-      break;
-    }
-    case P4_FUNCDEF: {
-      FuncDef *pDef = pOp->p4.pFunc;
-      sqlite3_snprintf(nTemp, zTemp, "%s(%d)", pDef->zName, pDef->nArg);
-      break;
-    }
-    case P4_INT64: {
-      sqlite3_snprintf(nTemp, zTemp, "%lld", *pOp->p4.pI64);
-      break;
-    }
-    case P4_INT32: {
-      sqlite3_snprintf(nTemp, zTemp, "%d", pOp->p4.i);
-      break;
-    }
-    case P4_REAL: {
-      sqlite3_snprintf(nTemp, zTemp, "%.16g", *pOp->p4.pReal);
-      break;
-    }
-    case P4_MEM: {
-      Mem *pMem = pOp->p4.pMem;
-      assert( (pMem->flags & MEM_Null)==0 );
-      if( pMem->flags & MEM_Str ){
-        zP4 = pMem->z;
-      }else if( pMem->flags & MEM_Int ){
-        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
-      }else if( pMem->flags & MEM_Real ){
-        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
+
+      /* Set the new 'max-root-page' value in the database header. This
+      ** is the old value less one, less one more if that happens to
+      ** be a root-page number, less one again if that is the
+      ** PENDING_BYTE_PAGE.
+      */
+      maxRootPgno--;
+      while( maxRootPgno==PENDING_BYTE_PAGE(pBt)
+             || PTRMAP_ISPAGE(pBt, maxRootPgno) ){
+        maxRootPgno--;
       }
-      break;
-    }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    case P4_VTAB: {
-      sqlite3_vtab *pVtab = pOp->p4.pVtab;
-      sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
-      break;
+      assert( maxRootPgno!=PENDING_BYTE_PAGE(pBt) );
+
+      rc = sqlite3BtreeUpdateMeta(p, 4, maxRootPgno);
+    }else{
+      freePage(pPage, &rc);
+      releasePage(pPage);
     }
 #endif
-    default: {
-      zP4 = pOp->p4.z;
-      if( zP4==0 ){
-        zP4 = zTemp;
-        zTemp[0] = 0;
-      }
-    }
+  }else{
+    /* If sqlite3BtreeDropTable was called on page 1.
+    ** This really never should happen except in a corrupt
+    ** database. 
+    */
+    zeroPage(pPage, PTF_INTKEY|PTF_LEAF );
+    releasePage(pPage);
   }
-  assert( zP4!=0 );
-  return zP4;
+  return rc;  
+}
+SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
+  int rc;
+  sqlite3BtreeEnter(p);
+  rc = btreeDropTable(p, iTable, piMoved);
+  sqlite3BtreeLeave(p);
+  return rc;
 }
-#endif
+
 
 /*
-** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
+** This function may only be called if the b-tree connection already
+** has a read or write transaction open on the database.
 **
+** Read the meta-information out of a database file.  Meta[0]
+** is the number of free pages currently in the database.  Meta[1]
+** through meta[15] are available for use by higher layers.  Meta[0]
+** is read-only, the others are read/write.
+** 
+** The schema layer numbers meta values differently.  At the schema
+** layer (and the SetCookie and ReadCookie opcodes) the number of
+** free pages is not visible.  So Cookie[0] is the same as Meta[1].
 */
-SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe *p, int i){
-  int mask;
-  assert( i>=0 && i<p->db->nDb );
-  assert( i<sizeof(p->btreeMask)*8 );
-  mask = 1<<i;
-  if( (p->btreeMask & mask)==0 ){
-    p->btreeMask |= mask;
-    sqlite3BtreeMutexArrayInsert(&p->aMutex, p->db->aDb[i].pBt);
-  }
-}
+SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *p, int idx, u32 *pMeta){
+  BtShared *pBt = p->pBt;
 
+  sqlite3BtreeEnter(p);
+  assert( p->inTrans>TRANS_NONE );
+  assert( SQLITE_OK==querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK) );
+  assert( pBt->pPage1 );
+  assert( idx>=0 && idx<=15 );
 
-#if defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
-/*
-** Print a single opcode.  This routine is used for debugging only.
-*/
-SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
-  char *zP4;
-  char zPtr[50];
-  static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
-  if( pOut==0 ) pOut = stdout;
-  zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
-  fprintf(pOut, zFormat1, pc, 
-      sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
-#ifdef SQLITE_DEBUG
-      pOp->zComment ? pOp->zComment : ""
-#else
-      ""
+  *pMeta = get4byte(&pBt->pPage1->aData[36 + idx*4]);
+
+  /* If auto-vacuum is disabled in this build and this is an auto-vacuum
+  ** database, mark the database as read-only.  */
+#ifdef SQLITE_OMIT_AUTOVACUUM
+  if( idx==BTREE_LARGEST_ROOT_PAGE && *pMeta>0 ) pBt->readOnly = 1;
 #endif
-  );
-  fflush(pOut);
+
+  sqlite3BtreeLeave(p);
 }
-#endif
 
 /*
-** Release an array of N Mem elements
+** Write meta-information back into the database.  Meta[0] is
+** read-only and may not be written.
 */
-static void releaseMemArray(Mem *p, int N, int freebuffers){
-  if( p && N ){
-    sqlite3 *db = p->db;
-    int malloc_failed = db->mallocFailed;
-    while( N-->0 ){
-      assert( N<2 || p[0].db==p[1].db );
-      if( freebuffers ){
-        sqlite3VdbeMemRelease(p);
-      }else{
-        sqlite3VdbeMemReleaseExternal(p);
-      }
-      p->flags = MEM_Null;
-      p++;
-    }
-    db->mallocFailed = malloc_failed;
-  }
-}
-
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-SQLITE_PRIVATE int sqlite3VdbeReleaseBuffers(Vdbe *p){
-  int ii;
-  int nFree = 0;
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  for(ii=1; ii<=p->nMem; ii++){
-    Mem *pMem = &p->aMem[ii];
-    if( pMem->z && pMem->flags&MEM_Dyn ){
-      assert( !pMem->xDel );
-      nFree += sqlite3MallocSize(pMem->z);
-      sqlite3VdbeMemRelease(pMem);
+SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree *p, int idx, u32 iMeta){
+  BtShared *pBt = p->pBt;
+  unsigned char *pP1;
+  int rc;
+  assert( idx>=1 && idx<=15 );
+  sqlite3BtreeEnter(p);
+  assert( p->inTrans==TRANS_WRITE );
+  assert( pBt->pPage1!=0 );
+  pP1 = pBt->pPage1->aData;
+  rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
+  if( rc==SQLITE_OK ){
+    put4byte(&pP1[36 + idx*4], iMeta);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( idx==BTREE_INCR_VACUUM ){
+      assert( pBt->autoVacuum || iMeta==0 );
+      assert( iMeta==0 || iMeta==1 );
+      pBt->incrVacuum = (u8)iMeta;
     }
+#endif
   }
-  return nFree;
+  sqlite3BtreeLeave(p);
+  return rc;
 }
-#endif
 
-#ifndef SQLITE_OMIT_EXPLAIN
+#ifndef SQLITE_OMIT_BTREECOUNT
 /*
-** Give a listing of the program in the virtual machine.
-**
-** The interface is the same as sqlite3VdbeExec().  But instead of
-** running the code, it invokes the callback once for each instruction.
-** This feature is used to implement "EXPLAIN".
+** The first argument, pCur, is a cursor opened on some b-tree. Count the
+** number of entries in the b-tree and write the result to *pnEntry.
 **
-** When p->explain==1, each instruction is listed.  When
-** p->explain==2, only OP_Explain instructions are listed and these
-** are shown in a different format.  p->explain==2 is used to implement
-** EXPLAIN QUERY PLAN.
+** SQLITE_OK is returned if the operation is successfully executed. 
+** Otherwise, if an error is encountered (i.e. an IO error or database
+** corruption) an SQLite error code is returned.
 */
-SQLITE_PRIVATE int sqlite3VdbeList(
-  Vdbe *p                   /* The VDBE */
-){
-  sqlite3 *db = p->db;
-  int i;
-  int rc = SQLITE_OK;
-  Mem *pMem = p->pResultSet = &p->aMem[1];
-
-  assert( p->explain );
-  if( p->magic!=VDBE_MAGIC_RUN ) return SQLITE_MISUSE;
-  assert( db->magic==SQLITE_MAGIC_BUSY );
-  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
+SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *pCur, i64 *pnEntry){
+  i64 nEntry = 0;                      /* Value to return in *pnEntry */
+  int rc;                              /* Return code */
+  rc = moveToRoot(pCur);
 
-  /* Even though this opcode does not use dynamic strings for
-  ** the result, result columns may become dynamic if the user calls
-  ** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
+  /* Unless an error occurs, the following loop runs one iteration for each
+  ** page in the B-Tree structure (not including overflow pages). 
   */
-  releaseMemArray(pMem, p->nMem, 1);
+  while( rc==SQLITE_OK ){
+    int iIdx;                          /* Index of child node in parent */
+    MemPage *pPage;                    /* Current page of the b-tree */
 
-  do{
-    i = p->pc++;
-  }while( i<p->nOp && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
-  if( i>=p->nOp ){
-    p->rc = SQLITE_OK;
-    rc = SQLITE_DONE;
-  }else if( db->u1.isInterrupted ){
-    p->rc = SQLITE_INTERRUPT;
-    rc = SQLITE_ERROR;
-    sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(p->rc), (char*)0);
-  }else{
-    char *z;
-    Op *pOp = &p->aOp[i];
-    if( p->explain==1 ){
-      pMem->flags = MEM_Int;
-      pMem->type = SQLITE_INTEGER;
-      pMem->u.i = i;                                /* Program counter */
-      pMem++;
-  
-      pMem->flags = MEM_Static|MEM_Str|MEM_Term;
-      pMem->z = (char*)sqlite3OpcodeName(pOp->opcode);  /* Opcode */
-      assert( pMem->z!=0 );
-      pMem->n = strlen(pMem->z);
-      pMem->type = SQLITE_TEXT;
-      pMem->enc = SQLITE_UTF8;
-      pMem++;
+    /* If this is a leaf page or the tree is not an int-key tree, then 
+    ** this page contains countable entries. Increment the entry counter
+    ** accordingly.
+    */
+    pPage = pCur->apPage[pCur->iPage];
+    if( pPage->leaf || !pPage->intKey ){
+      nEntry += pPage->nCell;
     }
 
-    pMem->flags = MEM_Int;
-    pMem->u.i = pOp->p1;                          /* P1 */
-    pMem->type = SQLITE_INTEGER;
-    pMem++;
-
-    pMem->flags = MEM_Int;
-    pMem->u.i = pOp->p2;                          /* P2 */
-    pMem->type = SQLITE_INTEGER;
-    pMem++;
+    /* pPage is a leaf node. This loop navigates the cursor so that it 
+    ** points to the first interior cell that it points to the parent of
+    ** the next page in the tree that has not yet been visited. The
+    ** pCur->aiIdx[pCur->iPage] value is set to the index of the parent cell
+    ** of the page, or to the number of cells in the page if the next page
+    ** to visit is the right-child of its parent.
+    **
+    ** If all pages in the tree have been visited, return SQLITE_OK to the
+    ** caller.
+    */
+    if( pPage->leaf ){
+      do {
+        if( pCur->iPage==0 ){
+          /* All pages of the b-tree have been visited. Return successfully. */
+          *pnEntry = nEntry;
+          return SQLITE_OK;
+        }
+        moveToParent(pCur);
+      }while ( pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell );
 
-    if( p->explain==1 ){
-      pMem->flags = MEM_Int;
-      pMem->u.i = pOp->p3;                          /* P3 */
-      pMem->type = SQLITE_INTEGER;
-      pMem++;
+      pCur->aiIdx[pCur->iPage]++;
+      pPage = pCur->apPage[pCur->iPage];
     }
 
-    if( sqlite3VdbeMemGrow(pMem, 32, 0) ){            /* P4 */
-      p->db->mallocFailed = 1;
-      return SQLITE_NOMEM;
-    }
-    pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
-    z = displayP4(pOp, pMem->z, 32);
-    if( z!=pMem->z ){
-      sqlite3VdbeMemSetStr(pMem, z, -1, SQLITE_UTF8, 0);
+    /* Descend to the child node of the cell that the cursor currently 
+    ** points at. This is the right-child if (iIdx==pPage->nCell).
+    */
+    iIdx = pCur->aiIdx[pCur->iPage];
+    if( iIdx==pPage->nCell ){
+      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
     }else{
-      assert( pMem->z!=0 );
-      pMem->n = strlen(pMem->z);
-      pMem->enc = SQLITE_UTF8;
+      rc = moveToChild(pCur, get4byte(findCell(pPage, iIdx)));
     }
-    pMem->type = SQLITE_TEXT;
-    pMem++;
+  }
 
-    if( p->explain==1 ){
-      if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
-        p->db->mallocFailed = 1;
-        return SQLITE_NOMEM;
-      }
-      pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
-      pMem->n = 2;
-      sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5);   /* P5 */
-      pMem->type = SQLITE_TEXT;
-      pMem->enc = SQLITE_UTF8;
-      pMem++;
-  
-#ifdef SQLITE_DEBUG
-      if( pOp->zComment ){
-        pMem->flags = MEM_Str|MEM_Term;
-        pMem->z = pOp->zComment;
-        pMem->n = strlen(pMem->z);
-        pMem->enc = SQLITE_UTF8;
-      }else
+  /* An error has occurred. Return an error code. */
+  return rc;
+}
 #endif
-      {
-        pMem->flags = MEM_Null;                       /* Comment */
-        pMem->type = SQLITE_NULL;
-      }
-    }
 
-    p->nResColumn = 8 - 5*(p->explain-1);
-    p->rc = SQLITE_OK;
-    rc = SQLITE_ROW;
+/*
+** Return the pager associated with a BTree.  This routine is used for
+** testing and debugging only.
+*/
+SQLITE_PRIVATE Pager *sqlite3BtreePager(Btree *p){
+  return p->pBt->pPager;
+}
+
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
+/*
+** Append a message to the error message string.
+*/
+static void checkAppendMsg(
+  IntegrityCk *pCheck,
+  char *zMsg1,
+  const char *zFormat,
+  ...
+){
+  va_list ap;
+  if( !pCheck->mxErr ) return;
+  pCheck->mxErr--;
+  pCheck->nErr++;
+  va_start(ap, zFormat);
+  if( pCheck->errMsg.nChar ){
+    sqlite3StrAccumAppend(&pCheck->errMsg, "\n", 1);
+  }
+  if( zMsg1 ){
+    sqlite3StrAccumAppend(&pCheck->errMsg, zMsg1, -1);
+  }
+  sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
+  va_end(ap);
+  if( pCheck->errMsg.mallocFailed ){
+    pCheck->mallocFailed = 1;
   }
-  return rc;
 }
-#endif /* SQLITE_OMIT_EXPLAIN */
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
-#ifdef SQLITE_DEBUG
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** Print the SQL that was used to generate a VDBE program.
+** Add 1 to the reference count for page iPage.  If this is the second
+** reference to the page, add an error message to pCheck->zErrMsg.
+** Return 1 if there are 2 ore more references to the page and 0 if
+** if this is the first reference to the page.
+**
+** Also check that the page number is in bounds.
 */
-SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe *p){
-  int nOp = p->nOp;
-  VdbeOp *pOp;
-  if( nOp<1 ) return;
-  pOp = &p->aOp[0];
-  if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
-    const char *z = pOp->p4.z;
-    while( isspace(*(u8*)z) ) z++;
-    printf("SQL: [%s]\n", z);
+static int checkRef(IntegrityCk *pCheck, Pgno iPage, char *zContext){
+  if( iPage==0 ) return 1;
+  if( iPage>pCheck->nPage ){
+    checkAppendMsg(pCheck, zContext, "invalid page number %d", iPage);
+    return 1;
+  }
+  if( pCheck->anRef[iPage]==1 ){
+    checkAppendMsg(pCheck, zContext, "2nd reference to page %d", iPage);
+    return 1;
+  }
+  return  (pCheck->anRef[iPage]++)>1;
+}
+
+#ifndef SQLITE_OMIT_AUTOVACUUM
+/*
+** Check that the entry in the pointer-map for page iChild maps to 
+** page iParent, pointer type ptrType. If not, append an error message
+** to pCheck.
+*/
+static void checkPtrmap(
+  IntegrityCk *pCheck,   /* Integrity check context */
+  Pgno iChild,           /* Child page number */
+  u8 eType,              /* Expected pointer map type */
+  Pgno iParent,          /* Expected pointer map parent page number */
+  char *zContext         /* Context description (used for error msg) */
+){
+  int rc;
+  u8 ePtrmapType;
+  Pgno iPtrmapParent;
+
+  rc = ptrmapGet(pCheck->pBt, iChild, &ePtrmapType, &iPtrmapParent);
+  if( rc!=SQLITE_OK ){
+    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ) pCheck->mallocFailed = 1;
+    checkAppendMsg(pCheck, zContext, "Failed to read ptrmap key=%d", iChild);
+    return;
+  }
+
+  if( ePtrmapType!=eType || iPtrmapParent!=iParent ){
+    checkAppendMsg(pCheck, zContext, 
+      "Bad ptr map entry key=%d expected=(%d,%d) got=(%d,%d)", 
+      iChild, eType, iParent, ePtrmapType, iPtrmapParent);
   }
 }
 #endif
 
-#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
 /*
-** Print an IOTRACE message showing SQL content.
+** Check the integrity of the freelist or of an overflow page list.
+** Verify that the number of pages on the list is N.
 */
-SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
-  int nOp = p->nOp;
-  VdbeOp *pOp;
-  if( sqlite3IoTrace==0 ) return;
-  if( nOp<1 ) return;
-  pOp = &p->aOp[0];
-  if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
-    int i, j;
-    char z[1000];
-    sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
-    for(i=0; isspace((unsigned char)z[i]); i++){}
-    for(j=0; z[i]; i++){
-      if( isspace((unsigned char)z[i]) ){
-        if( z[i-1]!=' ' ){
-          z[j++] = ' ';
-        }
+static void checkList(
+  IntegrityCk *pCheck,  /* Integrity checking context */
+  int isFreeList,       /* True for a freelist.  False for overflow page list */
+  int iPage,            /* Page number for first page in the list */
+  int N,                /* Expected number of pages in the list */
+  char *zContext        /* Context for error messages */
+){
+  int i;
+  int expected = N;
+  int iFirst = iPage;
+  while( N-- > 0 && pCheck->mxErr ){
+    DbPage *pOvflPage;
+    unsigned char *pOvflData;
+    if( iPage<1 ){
+      checkAppendMsg(pCheck, zContext,
+         "%d of %d pages missing from overflow list starting at %d",
+          N+1, expected, iFirst);
+      break;
+    }
+    if( checkRef(pCheck, iPage, zContext) ) break;
+    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage) ){
+      checkAppendMsg(pCheck, zContext, "failed to get page %d", iPage);
+      break;
+    }
+    pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
+    if( isFreeList ){
+      int n = get4byte(&pOvflData[4]);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      if( pCheck->pBt->autoVacuum ){
+        checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
+      }
+#endif
+      if( n>pCheck->pBt->usableSize/4-2 ){
+        checkAppendMsg(pCheck, zContext,
+           "freelist leaf count too big on page %d", iPage);
+        N--;
       }else{
-        z[j++] = z[i];
+        for(i=0; i<n; i++){
+          Pgno iFreePage = get4byte(&pOvflData[8+i*4]);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+          if( pCheck->pBt->autoVacuum ){
+            checkPtrmap(pCheck, iFreePage, PTRMAP_FREEPAGE, 0, zContext);
+          }
+#endif
+          checkRef(pCheck, iFreePage, zContext);
+        }
+        N -= n;
       }
     }
-    z[j] = 0;
-    sqlite3IoTrace("SQL %s\n", z);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    else{
+      /* If this database supports auto-vacuum and iPage is not the last
+      ** page in this overflow list, check that the pointer-map entry for
+      ** the following page matches iPage.
+      */
+      if( pCheck->pBt->autoVacuum && N>0 ){
+        i = get4byte(pOvflData);
+        checkPtrmap(pCheck, i, PTRMAP_OVERFLOW2, iPage, zContext);
+      }
+    }
+#endif
+    iPage = get4byte(pOvflData);
+    sqlite3PagerUnref(pOvflPage);
   }
 }
-#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
-
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** Prepare a virtual machine for execution.  This involves things such
-** as allocating stack space and initializing the program counter.
-** After the VDBE has be prepped, it can be executed by one or more
-** calls to sqlite3VdbeExec().  
+** Do various sanity checks on a single page of a tree.  Return
+** the tree depth.  Root pages return 0.  Parents of root pages
+** return 1, and so forth.
+** 
+** These checks are done:
 **
-** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
-** VDBE_MAGIC_RUN.
+**      1.  Make sure that cells and freeblocks do not overlap
+**          but combine to completely cover the page.
+**  NO  2.  Make sure cell keys are in order.
+**  NO  3.  Make sure no key is less than or equal to zLowerBound.
+**  NO  4.  Make sure no key is greater than or equal to zUpperBound.
+**      5.  Check the integrity of overflow pages.
+**      6.  Recursively call checkTreePage on all children.
+**      7.  Verify that the depth of all children is the same.
+**      8.  Make sure this page is at least 33% full or else it is
+**          the root of the tree.
 */
-SQLITE_PRIVATE void sqlite3VdbeMakeReady(
-  Vdbe *p,                       /* The VDBE */
-  int nVar,                      /* Number of '?' see in the SQL statement */
-  int nMem,                      /* Number of memory cells to allocate */
-  int nCursor,                   /* Number of cursors to allocate */
-  int isExplain                  /* True if the EXPLAIN keywords is present */
+static int checkTreePage(
+  IntegrityCk *pCheck,  /* Context for the sanity check */
+  int iPage,            /* Page number of the page to check */
+  char *zParentContext  /* Parent context */
 ){
-  int n;
-  sqlite3 *db = p->db;
+  MemPage *pPage;
+  int i, rc, depth, d2, pgno, cnt;
+  int hdr, cellStart;
+  int nCell;
+  u8 *data;
+  BtShared *pBt;
+  int usableSize;
+  char zContext[100];
+  char *hit = 0;
 
-  assert( p!=0 );
-  assert( p->magic==VDBE_MAGIC_INIT );
+  sqlite3_snprintf(sizeof(zContext), zContext, "Page %d: ", iPage);
 
-  /* There should be at least one opcode.
+  /* Check that the page exists
   */
-  assert( p->nOp>0 );
+  pBt = pCheck->pBt;
+  usableSize = pBt->usableSize;
+  if( iPage==0 ) return 0;
+  if( checkRef(pCheck, iPage, zParentContext) ) return 0;
+  if( (rc = btreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
+    checkAppendMsg(pCheck, zContext,
+       "unable to get the page. error code=%d", rc);
+    return 0;
+  }
 
-  /* Set the magic to VDBE_MAGIC_RUN sooner rather than later. This
-   * is because the call to resizeOpArray() below may shrink the
-   * p->aOp[] array to save memory if called when in VDBE_MAGIC_RUN 
-   * state.
-   */
-  p->magic = VDBE_MAGIC_RUN;
+  /* Clear MemPage.isInit to make sure the corruption detection code in
+  ** btreeInitPage() is executed.  */
+  pPage->isInit = 0;
+  if( (rc = btreeInitPage(pPage))!=0 ){
+    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
+    checkAppendMsg(pCheck, zContext, 
+                   "btreeInitPage() returns error code %d", rc);
+    releasePage(pPage);
+    return 0;
+  }
 
-  /* For each cursor required, also allocate a memory cell. Memory
-  ** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
-  ** the vdbe program. Instead they are used to allocate space for
-  ** Cursor/BtCursor structures. The blob of memory associated with 
-  ** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
-  ** stores the blob of memory associated with cursor 1, etc.
-  **
-  ** See also: allocateCursor().
+  /* Check out all the cells.
   */
-  nMem += nCursor;
+  depth = 0;
+  for(i=0; i<pPage->nCell && pCheck->mxErr; i++){
+    u8 *pCell;
+    u32 sz;
+    CellInfo info;
 
-  /*
-  ** Allocation space for registers.
-  */
-  if( p->aMem==0 ){
-    int nArg;       /* Maximum number of args passed to a user function. */
-    resolveP2Values(p, &nArg);
-    /*resizeOpArray(p, p->nOp);*/
-    assert( nVar>=0 );
-    if( isExplain && nMem<10 ){
-      p->nMem = nMem = 10;
-    }
-    p->aMem = sqlite3DbMallocZero(db,
-        nMem*sizeof(Mem)               /* aMem */
-      + nVar*sizeof(Mem)               /* aVar */
-      + nArg*sizeof(Mem*)              /* apArg */
-      + nVar*sizeof(char*)             /* azVar */
-      + nCursor*sizeof(Cursor*) + 1    /* apCsr */
-    );
-    if( !db->mallocFailed ){
-      p->aMem--;             /* aMem[] goes from 1..nMem */
-      p->nMem = nMem;        /*       not from 0..nMem-1 */
-      p->aVar = &p->aMem[nMem+1];
-      p->nVar = nVar;
-      p->okVar = 0;
-      p->apArg = (Mem**)&p->aVar[nVar];
-      p->azVar = (char**)&p->apArg[nArg];
-      p->apCsr = (Cursor**)&p->azVar[nVar];
-      p->nCursor = nCursor;
-      for(n=0; n<nVar; n++){
-        p->aVar[n].flags = MEM_Null;
-        p->aVar[n].db = db;
+    /* Check payload overflow pages
+    */
+    sqlite3_snprintf(sizeof(zContext), zContext,
+             "On tree page %d cell %d: ", iPage, i);
+    pCell = findCell(pPage,i);
+    btreeParseCellPtr(pPage, pCell, &info);
+    sz = info.nData;
+    if( !pPage->intKey ) sz += (int)info.nKey;
+    assert( sz==info.nPayload );
+    if( (sz>info.nLocal) 
+     && (&pCell[info.iOverflow]<=&pPage->aData[pBt->usableSize])
+    ){
+      int nPage = (sz - info.nLocal + usableSize - 5)/(usableSize - 4);
+      Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      if( pBt->autoVacuum ){
+        checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage, zContext);
       }
-      for(n=1; n<=nMem; n++){
-        p->aMem[n].flags = MEM_Null;
-        p->aMem[n].db = db;
+#endif
+      checkList(pCheck, 0, pgnoOvfl, nPage, zContext);
+    }
+
+    /* Check sanity of left child page.
+    */
+    if( !pPage->leaf ){
+      pgno = get4byte(pCell);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+      if( pBt->autoVacuum ){
+        checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, zContext);
+      }
+#endif
+      d2 = checkTreePage(pCheck, pgno, zContext);
+      if( i>0 && d2!=depth ){
+        checkAppendMsg(pCheck, zContext, "Child page depth differs");
       }
+      depth = d2;
     }
   }
-#ifdef SQLITE_DEBUG
-  for(n=1; n<p->nMem; n++){
-    assert( p->aMem[n].db==db );
-  }
+  if( !pPage->leaf ){
+    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+    sqlite3_snprintf(sizeof(zContext), zContext, 
+                     "On page %d at right child: ", iPage);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pBt->autoVacuum ){
+      checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, 0);
+    }
 #endif
-
-  p->pc = -1;
-  p->rc = SQLITE_OK;
-  p->uniqueCnt = 0;
-  p->returnDepth = 0;
-  p->errorAction = OE_Abort;
-  p->explain |= isExplain;
-  p->magic = VDBE_MAGIC_RUN;
-  p->nChange = 0;
-  p->cacheCtr = 1;
-  p->minWriteFileFormat = 255;
-  p->openedStatement = 0;
-#ifdef VDBE_PROFILE
-  {
-    int i;
-    for(i=0; i<p->nOp; i++){
-      p->aOp[i].cnt = 0;
-      p->aOp[i].cycles = 0;
+    checkTreePage(pCheck, pgno, zContext);
+  }
+ 
+  /* Check for complete coverage of the page
+  */
+  data = pPage->aData;
+  hdr = pPage->hdrOffset;
+  hit = sqlite3PageMalloc( pBt->pageSize );
+  if( hit==0 ){
+    pCheck->mallocFailed = 1;
+  }else{
+    u16 contentOffset = get2byte(&data[hdr+5]);
+    assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
+    memset(hit+contentOffset, 0, usableSize-contentOffset);
+    memset(hit, 1, contentOffset);
+    nCell = get2byte(&data[hdr+3]);
+    cellStart = hdr + 12 - 4*pPage->leaf;
+    for(i=0; i<nCell; i++){
+      int pc = get2byte(&data[cellStart+i*2]);
+      u16 size = 1024;
+      int j;
+      if( pc<=usableSize-4 ){
+        size = cellSizePtr(pPage, &data[pc]);
+      }
+      if( (pc+size-1)>=usableSize ){
+        checkAppendMsg(pCheck, 0, 
+            "Corruption detected in cell %d on page %d",i,iPage,0);
+      }else{
+        for(j=pc+size-1; j>=pc; j--) hit[j]++;
+      }
+    }
+    i = get2byte(&data[hdr+1]);
+    while( i>0 ){
+      int size, j;
+      assert( i<=usableSize-4 );     /* Enforced by btreeInitPage() */
+      size = get2byte(&data[i+2]);
+      assert( i+size<=usableSize );  /* Enforced by btreeInitPage() */
+      for(j=i+size-1; j>=i; j--) hit[j]++;
+      j = get2byte(&data[i]);
+      assert( j==0 || j>i+size );  /* Enforced by btreeInitPage() */
+      assert( j<=usableSize-4 );   /* Enforced by btreeInitPage() */
+      i = j;
+    }
+    for(i=cnt=0; i<usableSize; i++){
+      if( hit[i]==0 ){
+        cnt++;
+      }else if( hit[i]>1 ){
+        checkAppendMsg(pCheck, 0,
+          "Multiple uses for byte %d of page %d", i, iPage);
+        break;
+      }
+    }
+    if( cnt!=data[hdr+7] ){
+      checkAppendMsg(pCheck, 0, 
+          "Fragmentation of %d bytes reported as %d on page %d",
+          cnt, data[hdr+7], iPage);
     }
   }
-#endif
+  sqlite3PageFree(hit);
+  releasePage(pPage);
+  return depth+1;
 }
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
 /*
-** Close a VDBE cursor and release all the resources that cursor 
-** happens to hold.
+** This routine does a complete check of the given BTree file.  aRoot[] is
+** an array of pages numbers were each page number is the root page of
+** a table.  nRoot is the number of entries in aRoot.
+**
+** A read-only or read-write transaction must be opened before calling
+** this function.
+**
+** Write the number of error seen in *pnErr.  Except for some memory
+** allocation errors,  an error message held in memory obtained from
+** malloc is returned if *pnErr is non-zero.  If *pnErr==0 then NULL is
+** returned.  If a memory allocation error occurs, NULL is returned.
 */
-SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *p, Cursor *pCx){
-  if( pCx==0 ){
-    return;
+SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(
+  Btree *p,     /* The btree to be checked */
+  int *aRoot,   /* An array of root pages numbers for individual trees */
+  int nRoot,    /* Number of entries in aRoot[] */
+  int mxErr,    /* Stop reporting errors after this many */
+  int *pnErr    /* Write number of errors seen to this variable */
+){
+  Pgno i;
+  int nRef;
+  IntegrityCk sCheck;
+  BtShared *pBt = p->pBt;
+  char zErr[100];
+
+  sqlite3BtreeEnter(p);
+  assert( p->inTrans>TRANS_NONE && pBt->inTransaction>TRANS_NONE );
+  nRef = sqlite3PagerRefcount(pBt->pPager);
+  sCheck.pBt = pBt;
+  sCheck.pPager = pBt->pPager;
+  sCheck.nPage = pagerPagecount(sCheck.pBt);
+  sCheck.mxErr = mxErr;
+  sCheck.nErr = 0;
+  sCheck.mallocFailed = 0;
+  *pnErr = 0;
+  if( sCheck.nPage==0 ){
+    sqlite3BtreeLeave(p);
+    return 0;
   }
-  if( pCx->pCursor ){
-    sqlite3BtreeCloseCursor(pCx->pCursor);
+  sCheck.anRef = sqlite3Malloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
+  if( !sCheck.anRef ){
+    *pnErr = 1;
+    sqlite3BtreeLeave(p);
+    return 0;
   }
-  if( pCx->pBt ){
-    sqlite3BtreeClose(pCx->pBt);
+  for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
+  i = PENDING_BYTE_PAGE(pBt);
+  if( i<=sCheck.nPage ){
+    sCheck.anRef[i] = 1;
   }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( pCx->pVtabCursor ){
-    sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
-    const sqlite3_module *pModule = pCx->pModule;
-    p->inVtabMethod = 1;
-    (void)sqlite3SafetyOff(p->db);
-    pModule->xClose(pVtabCursor);
-    (void)sqlite3SafetyOn(p->db);
-    p->inVtabMethod = 0;
+  sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), 20000);
+
+  /* Check the integrity of the freelist
+  */
+  checkList(&sCheck, 1, get4byte(&pBt->pPage1->aData[32]),
+            get4byte(&pBt->pPage1->aData[36]), "Main freelist: ");
+
+  /* Check all the tables.
+  */
+  for(i=0; (int)i<nRoot && sCheck.mxErr; i++){
+    if( aRoot[i]==0 ) continue;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( pBt->autoVacuum && aRoot[i]>1 ){
+      checkPtrmap(&sCheck, aRoot[i], PTRMAP_ROOTPAGE, 0, 0);
+    }
+#endif
+    checkTreePage(&sCheck, aRoot[i], "List of tree roots: ");
   }
+
+  /* Make sure every page in the file is referenced
+  */
+  for(i=1; i<=sCheck.nPage && sCheck.mxErr; i++){
+#ifdef SQLITE_OMIT_AUTOVACUUM
+    if( sCheck.anRef[i]==0 ){
+      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
+    }
+#else
+    /* If the database supports auto-vacuum, make sure no tables contain
+    ** references to pointer-map pages.
+    */
+    if( sCheck.anRef[i]==0 && 
+       (PTRMAP_PAGENO(pBt, i)!=i || !pBt->autoVacuum) ){
+      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
+    }
+    if( sCheck.anRef[i]!=0 && 
+       (PTRMAP_PAGENO(pBt, i)==i && pBt->autoVacuum) ){
+      checkAppendMsg(&sCheck, 0, "Pointer map page %d is referenced", i);
+    }
 #endif
-  if( !pCx->ephemPseudoTable ){
-    sqlite3_free(pCx->pData);
   }
-  /* memset(pCx, 0, sizeof(Cursor)); */
-  /* sqlite3_free(pCx->aType); */
-  /* sqlite3_free(pCx); */
+
+  /* Make sure this analysis did not leave any unref() pages.
+  ** This is an internal consistency check; an integrity check
+  ** of the integrity check.
+  */
+  if( NEVER(nRef != sqlite3PagerRefcount(pBt->pPager)) ){
+    checkAppendMsg(&sCheck, 0, 
+      "Outstanding page count goes from %d to %d during this analysis",
+      nRef, sqlite3PagerRefcount(pBt->pPager)
+    );
+  }
+
+  /* Clean  up and report errors.
+  */
+  sqlite3BtreeLeave(p);
+  sqlite3_free(sCheck.anRef);
+  if( sCheck.mallocFailed ){
+    sqlite3StrAccumReset(&sCheck.errMsg);
+    *pnErr = sCheck.nErr+1;
+    return 0;
+  }
+  *pnErr = sCheck.nErr;
+  if( sCheck.nErr==0 ) sqlite3StrAccumReset(&sCheck.errMsg);
+  return sqlite3StrAccumFinish(&sCheck.errMsg);
 }
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
 /*
-** Close all cursors except for VTab cursors that are currently
-** in use.
+** Return the full pathname of the underlying database file.
+**
+** The pager filename is invariant as long as the pager is
+** open so it is safe to access without the BtShared mutex.
 */
-static void closeAllCursorsExceptActiveVtabs(Vdbe *p){
-  int i;
-  if( p->apCsr==0 ) return;
-  for(i=0; i<p->nCursor; i++){
-    Cursor *pC = p->apCsr[i];
-    if( pC && (!p->inVtabMethod || !pC->pVtabCursor) ){
-      sqlite3VdbeFreeCursor(p, pC);
-      p->apCsr[i] = 0;
-    }
-  }
+SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *p){
+  assert( p->pBt->pPager!=0 );
+  return sqlite3PagerFilename(p->pBt->pPager);
 }
 
 /*
-** Clean up the VM after execution.
+** Return the pathname of the journal file for this database. The return
+** value of this routine is the same regardless of whether the journal file
+** has been created or not.
 **
-** This routine will automatically close any cursors, lists, and/or
-** sorters that were left open.  It also deletes the values of
-** variables in the aVar[] array.
+** The pager journal filename is invariant as long as the pager is
+** open so it is safe to access without the BtShared mutex.
 */
-static void Cleanup(Vdbe *p, int freebuffers){
-  int i;
-  closeAllCursorsExceptActiveVtabs(p);
-  for(i=1; i<=p->nMem; i++){
-    MemSetTypeFlag(&p->aMem[i], MEM_Null);
-  }
-  releaseMemArray(&p->aMem[1], p->nMem, freebuffers);
-  sqlite3VdbeFifoClear(&p->sFifo);
-  if( p->contextStack ){
-    for(i=0; i<p->contextStackTop; i++){
-      sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
-    }
-    sqlite3_free(p->contextStack);
-  }
-  p->contextStack = 0;
-  p->contextStackDepth = 0;
-  p->contextStackTop = 0;
-  sqlite3_free(p->zErrMsg);
-  p->zErrMsg = 0;
-  p->pResultSet = 0;
+SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *p){
+  assert( p->pBt->pPager!=0 );
+  return sqlite3PagerJournalname(p->pBt->pPager);
 }
 
 /*
-** Set the number of result columns that will be returned by this SQL
-** statement. This is now set at compile time, rather than during
-** execution of the vdbe program so that sqlite3_column_count() can
-** be called on an SQL statement before sqlite3_step().
+** Return non-zero if a transaction is active.
 */
-SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
-  Mem *pColName;
-  int n;
-
-  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N, 1);
-  sqlite3_free(p->aColName);
-  n = nResColumn*COLNAME_N;
-  p->nResColumn = nResColumn;
-  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(p->db, sizeof(Mem)*n );
-  if( p->aColName==0 ) return;
-  while( n-- > 0 ){
-    pColName->flags = MEM_Null;
-    pColName->db = p->db;
-    pColName++;
-  }
+SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree *p){
+  assert( p==0 || sqlite3_mutex_held(p->db->mutex) );
+  return (p && (p->inTrans==TRANS_WRITE));
 }
 
 /*
-** Set the name of the idx'th column to be returned by the SQL statement.
-** zName must be a pointer to a nul terminated string.
-**
-** This call must be made after a call to sqlite3VdbeSetNumCols().
-**
-** If N==P4_STATIC  it means that zName is a pointer to a constant static
-** string and we can just copy the pointer. If it is P4_DYNAMIC, then 
-** the string is freed using sqlite3_free() when the vdbe is finished with
-** it. Otherwise, N bytes of zName are copied.
+** Return non-zero if a read (or write) transaction is active.
 */
-SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe *p, int idx, int var, const char *zName, int N){
-  int rc;
-  Mem *pColName;
-  assert( idx<p->nResColumn );
-  assert( var<COLNAME_N );
-  if( p->db->mallocFailed ) return SQLITE_NOMEM;
-  assert( p->aColName!=0 );
-  pColName = &(p->aColName[idx+var*p->nResColumn]);
-  if( N==P4_DYNAMIC || N==P4_STATIC ){
-    rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, SQLITE_STATIC);
-  }else{
-    rc = sqlite3VdbeMemSetStr(pColName, zName, N, SQLITE_UTF8,SQLITE_TRANSIENT);
-  }
-  if( rc==SQLITE_OK && N==P4_DYNAMIC ){
-    pColName->flags &= (~MEM_Static);
-    pColName->zMalloc = pColName->z;
+SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree *p){
+  assert( p );
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  return p->inTrans!=TRANS_NONE;
+}
+
+SQLITE_PRIVATE int sqlite3BtreeIsInBackup(Btree *p){
+  assert( p );
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  return p->nBackup!=0;
+}
+
+/*
+** This function returns a pointer to a blob of memory associated with
+** a single shared-btree. The memory is used by client code for its own
+** purposes (for example, to store a high-level schema associated with 
+** the shared-btree). The btree layer manages reference counting issues.
+**
+** The first time this is called on a shared-btree, nBytes bytes of memory
+** are allocated, zeroed, and returned to the caller. For each subsequent 
+** call the nBytes parameter is ignored and a pointer to the same blob
+** of memory returned. 
+**
+** If the nBytes parameter is 0 and the blob of memory has not yet been
+** allocated, a null pointer is returned. If the blob has already been
+** allocated, it is returned as normal.
+**
+** Just before the shared-btree is closed, the function passed as the 
+** xFree argument when the memory allocation was made is invoked on the 
+** blob of allocated memory. This function should not call sqlite3_free()
+** on the memory, the btree layer does that.
+*/
+SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
+  BtShared *pBt = p->pBt;
+  sqlite3BtreeEnter(p);
+  if( !pBt->pSchema && nBytes ){
+    pBt->pSchema = sqlite3MallocZero(nBytes);
+    pBt->xFreeSchema = xFree;
   }
+  sqlite3BtreeLeave(p);
+  return pBt->pSchema;
+}
+
+/*
+** Return SQLITE_LOCKED_SHAREDCACHE if another user of the same shared 
+** btree as the argument handle holds an exclusive lock on the 
+** sqlite_master table. Otherwise SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *p){
+  int rc;
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  sqlite3BtreeEnter(p);
+  rc = querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK);
+  assert( rc==SQLITE_OK || rc==SQLITE_LOCKED_SHAREDCACHE );
+  sqlite3BtreeLeave(p);
   return rc;
 }
 
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
 /*
-** A read or write transaction may or may not be active on database handle
-** db. If a transaction is active, commit it. If there is a
-** write-transaction spanning more than one database file, this routine
-** takes care of the master journal trickery.
+** Obtain a lock on the table whose root page is iTab.  The
+** lock is a write lock if isWritelock is true or a read lock
+** if it is false.
 */
-static int vdbeCommit(sqlite3 *db){
-  int i;
-  int nTrans = 0;  /* Number of databases with an active write-transaction */
+SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
   int rc = SQLITE_OK;
-  int needXcommit = 0;
+  assert( p->inTrans!=TRANS_NONE );
+  if( p->sharable ){
+    u8 lockType = READ_LOCK + isWriteLock;
+    assert( READ_LOCK+1==WRITE_LOCK );
+    assert( isWriteLock==0 || isWriteLock==1 );
 
-  /* Before doing anything else, call the xSync() callback for any
-  ** virtual module tables written in this transaction. This has to
-  ** be done before determining whether a master journal file is 
-  ** required, as an xSync() callback may add an attached database
-  ** to the transaction.
-  */
-  rc = sqlite3VtabSync(db, rc);
+    sqlite3BtreeEnter(p);
+    rc = querySharedCacheTableLock(p, iTab, lockType);
+    if( rc==SQLITE_OK ){
+      rc = setSharedCacheTableLock(p, iTab, lockType);
+    }
+    sqlite3BtreeLeave(p);
+  }
+  return rc;
+}
+#endif
+
+#ifndef SQLITE_OMIT_INCRBLOB
+/*
+** Argument pCsr must be a cursor opened for writing on an 
+** INTKEY table currently pointing at a valid table entry. 
+** This function modifies the data stored as part of that entry.
+**
+** Only the data content may only be modified, it is not possible to 
+** change the length of the data stored. If this function is called with
+** parameters that attempt to write past the end of the existing data,
+** no modifications are made and SQLITE_CORRUPT is returned.
+*/
+SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
+  int rc;
+  assert( cursorHoldsMutex(pCsr) );
+  assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
+  assert( pCsr->isIncrblobHandle );
+
+  rc = restoreCursorPosition(pCsr);
   if( rc!=SQLITE_OK ){
     return rc;
   }
-
-  /* This loop determines (a) if the commit hook should be invoked and
-  ** (b) how many database files have open write transactions, not 
-  ** including the temp database. (b) is important because if more than 
-  ** one database file has an open write transaction, a master journal
-  ** file is required for an atomic commit.
-  */ 
-  for(i=0; i<db->nDb; i++){ 
-    Btree *pBt = db->aDb[i].pBt;
-    if( sqlite3BtreeIsInTrans(pBt) ){
-      needXcommit = 1;
-      if( i!=1 ) nTrans++;
-    }
+  assert( pCsr->eState!=CURSOR_REQUIRESEEK );
+  if( pCsr->eState!=CURSOR_VALID ){
+    return SQLITE_ABORT;
   }
 
-  /* If there are any write-transactions at all, invoke the commit hook */
-  if( needXcommit && db->xCommitCallback ){
-    (void)sqlite3SafetyOff(db);
-    rc = db->xCommitCallback(db->pCommitArg);
-    (void)sqlite3SafetyOn(db);
-    if( rc ){
-      return SQLITE_CONSTRAINT;
-    }
+  /* Check some assumptions: 
+  **   (a) the cursor is open for writing,
+  **   (b) there is a read/write transaction open,
+  **   (c) the connection holds a write-lock on the table (if required),
+  **   (d) there are no conflicting read-locks, and
+  **   (e) the cursor points at a valid row of an intKey table.
+  */
+  if( !pCsr->wrFlag ){
+    return SQLITE_READONLY;
   }
+  assert( !pCsr->pBt->readOnly && pCsr->pBt->inTransaction==TRANS_WRITE );
+  assert( hasSharedCacheTableLock(pCsr->pBtree, pCsr->pgnoRoot, 0, 2) );
+  assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
+  assert( pCsr->apPage[pCsr->iPage]->intKey );
 
-  /* The simple case - no more than one database file (not counting the
-  ** TEMP database) has a transaction active.   There is no need for the
-  ** master-journal.
-  **
-  ** If the return value of sqlite3BtreeGetFilename() is a zero length
-  ** string, it means the main database is :memory:.  In that case we do
-  ** not support atomic multi-file commits, so use the simple case then
-  ** too.
-  */
-  if( 0==strlen(sqlite3BtreeGetFilename(db->aDb[0].pBt)) || nTrans<=1 ){
-    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
-      }
-    }
+  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
+}
 
-    /* Do the commit only if all databases successfully complete phase 1. 
-    ** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
-    ** IO error while deleting or truncating a journal file. It is unlikely,
-    ** but could happen. In this case abandon processing and return the error.
-    */
-    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        rc = sqlite3BtreeCommitPhaseTwo(pBt);
-      }
-    }
-    if( rc==SQLITE_OK ){
-      sqlite3VtabCommit(db);
-    }
-  }
+/* 
+** Set a flag on this cursor to cache the locations of pages from the 
+** overflow list for the current row. This is used by cursors opened
+** for incremental blob IO only.
+**
+** This function sets a flag only. The actual page location cache
+** (stored in BtCursor.aOverflow[]) is allocated and used by function
+** accessPayload() (the worker function for sqlite3BtreeData() and
+** sqlite3BtreePutData()).
+*/
+SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *pCur){
+  assert( cursorHoldsMutex(pCur) );
+  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
+  assert(!pCur->isIncrblobHandle);
+  assert(!pCur->aOverflow);
+  pCur->isIncrblobHandle = 1;
+}
+#endif
 
-  /* The complex case - There is a multi-file write-transaction active.
-  ** This requires a master journal file to ensure the transaction is
-  ** committed atomicly.
+/************** End of btree.c ***********************************************/
+/************** Begin file backup.c ******************************************/
+/*
+** 2009 January 28
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the implementation of the sqlite3_backup_XXX() 
+** API functions and the related features.
+**
+** $Id: backup.c,v 1.19 2009/07/06 19:03:13 drh Exp $
+*/
+
+/* Macro to find the minimum of two numeric values.
+*/
+#ifndef MIN
+# define MIN(x,y) ((x)<(y)?(x):(y))
+#endif
+
+/*
+** Structure allocated for each backup operation.
+*/
+struct sqlite3_backup {
+  sqlite3* pDestDb;        /* Destination database handle */
+  Btree *pDest;            /* Destination b-tree file */
+  u32 iDestSchema;         /* Original schema cookie in destination */
+  int bDestLocked;         /* True once a write-transaction is open on pDest */
+
+  Pgno iNext;              /* Page number of the next source page to copy */
+  sqlite3* pSrcDb;         /* Source database handle */
+  Btree *pSrc;             /* Source b-tree file */
+
+  int rc;                  /* Backup process error code */
+
+  /* These two variables are set by every call to backup_step(). They are
+  ** read by calls to backup_remaining() and backup_pagecount().
   */
-#ifndef SQLITE_OMIT_DISKIO
-  else{
-    sqlite3_vfs *pVfs = db->pVfs;
-    int needSync = 0;
-    char *zMaster = 0;   /* File-name for the master journal */
-    char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
-    sqlite3_file *pMaster = 0;
-    i64 offset = 0;
+  Pgno nRemaining;         /* Number of pages left to copy */
+  Pgno nPagecount;         /* Total number of pages to copy */
 
-    /* Select a master journal file name */
-    do {
-      u32 random;
-      sqlite3_free(zMaster);
-      sqlite3_randomness(sizeof(random), &random);
-      zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, random&0x7fffffff);
-      if( !zMaster ){
-        return SQLITE_NOMEM;
-      }
-      rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS);
-    }while( rc==1 );
-    if( rc!=0 ){
-      rc = SQLITE_IOERR_NOMEM;
-    }else{
-      /* Open the master journal. */
-      rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster, 
-          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
-          SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_MASTER_JOURNAL, 0
-      );
-    }
-    if( rc!=SQLITE_OK ){
-      sqlite3_free(zMaster);
-      return rc;
-    }
- 
-    /* Write the name of each database file in the transaction into the new
-    ** master journal file. If an error occurs at this point close
-    ** and delete the master journal file. All the individual journal files
-    ** still have 'null' as the master journal pointer, so they will roll
-    ** back independently if a failure occurs.
-    */
-    for(i=0; i<db->nDb; i++){
-      Btree *pBt = db->aDb[i].pBt;
-      if( i==1 ) continue;   /* Ignore the TEMP database */
-      if( sqlite3BtreeIsInTrans(pBt) ){
-        char const *zFile = sqlite3BtreeGetJournalname(pBt);
-        if( zFile[0]==0 ) continue;  /* Ignore :memory: databases */
-        if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
-          needSync = 1;
-        }
-        rc = sqlite3OsWrite(pMaster, zFile, strlen(zFile)+1, offset);
-        offset += strlen(zFile)+1;
-        if( rc!=SQLITE_OK ){
-          sqlite3OsCloseFree(pMaster);
-          sqlite3OsDelete(pVfs, zMaster, 0);
-          sqlite3_free(zMaster);
-          return rc;
-        }
-      }
-    }
+  int isAttached;          /* True once backup has been registered with pager */
+  sqlite3_backup *pNext;   /* Next backup associated with source pager */
+};
 
-    /* Sync the master journal file. If the IOCAP_SEQUENTIAL device
-    ** flag is set this is not required.
-    */
-    zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
-    if( (needSync 
-     && (0==(sqlite3OsDeviceCharacteristics(pMaster)&SQLITE_IOCAP_SEQUENTIAL))
-     && (rc=sqlite3OsSync(pMaster, SQLITE_SYNC_NORMAL))!=SQLITE_OK) ){
-      sqlite3OsCloseFree(pMaster);
-      sqlite3OsDelete(pVfs, zMaster, 0);
-      sqlite3_free(zMaster);
-      return rc;
-    }
+/*
+** THREAD SAFETY NOTES:
+**
+**   Once it has been created using backup_init(), a single sqlite3_backup
+**   structure may be accessed via two groups of thread-safe entry points:
+**
+**     * Via the sqlite3_backup_XXX() API function backup_step() and 
+**       backup_finish(). Both these functions obtain the source database
+**       handle mutex and the mutex associated with the source BtShared 
+**       structure, in that order.
+**
+**     * Via the BackupUpdate() and BackupRestart() functions, which are
+**       invoked by the pager layer to report various state changes in
+**       the page cache associated with the source database. The mutex
+**       associated with the source database BtShared structure will always 
+**       be held when either of these functions are invoked.
+**
+**   The other sqlite3_backup_XXX() API functions, backup_remaining() and
+**   backup_pagecount() are not thread-safe functions. If they are called
+**   while some other thread is calling backup_step() or backup_finish(),
+**   the values returned may be invalid. There is no way for a call to
+**   BackupUpdate() or BackupRestart() to interfere with backup_remaining()
+**   or backup_pagecount().
+**
+**   Depending on the SQLite configuration, the database handles and/or
+**   the Btree objects may have their own mutexes that require locking.
+**   Non-sharable Btrees (in-memory databases for example), do not have
+**   associated mutexes.
+*/
 
-    /* Sync all the db files involved in the transaction. The same call
-    ** sets the master journal pointer in each individual journal. If
-    ** an error occurs here, do not delete the master journal file.
-    **
-    ** If the error occurs during the first call to
-    ** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
-    ** master journal file will be orphaned. But we cannot delete it,
-    ** in case the master journal file name was written into the journal
-    ** file before the failure occured.
-    */
-    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
+/*
+** Return a pointer corresponding to database zDb (i.e. "main", "temp")
+** in connection handle pDb. If such a database cannot be found, return
+** a NULL pointer and write an error message to pErrorDb.
+**
+** If the "temp" database is requested, it may need to be opened by this 
+** function. If an error occurs while doing so, return 0 and write an 
+** error message to pErrorDb.
+*/
+static Btree *findBtree(sqlite3 *pErrorDb, sqlite3 *pDb, const char *zDb){
+  int i = sqlite3FindDbName(pDb, zDb);
+
+  if( i==1 ){
+    Parse *pParse;
+    int rc = 0;
+    pParse = sqlite3StackAllocZero(pErrorDb, sizeof(*pParse));
+    if( pParse==0 ){
+      sqlite3Error(pErrorDb, SQLITE_NOMEM, "out of memory");
+      rc = SQLITE_NOMEM;
+    }else{
+      pParse->db = pDb;
+      if( sqlite3OpenTempDatabase(pParse) ){
+        sqlite3ErrorClear(pParse);
+        sqlite3Error(pErrorDb, pParse->rc, "%s", pParse->zErrMsg);
+        rc = SQLITE_ERROR;
       }
+      sqlite3StackFree(pErrorDb, pParse);
     }
-    sqlite3OsCloseFree(pMaster);
-    if( rc!=SQLITE_OK ){
-      sqlite3_free(zMaster);
-      return rc;
-    }
-
-    /* Delete the master journal file. This commits the transaction. After
-    ** doing this the directory is synced again before any individual
-    ** transaction files are deleted.
-    */
-    rc = sqlite3OsDelete(pVfs, zMaster, 1);
-    sqlite3_free(zMaster);
-    zMaster = 0;
     if( rc ){
-      return rc;
-    }
-
-    /* All files and directories have already been synced, so the following
-    ** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
-    ** deleting or truncating journals. If something goes wrong while
-    ** this is happening we don't really care. The integrity of the
-    ** transaction is already guaranteed, but some stray 'cold' journals
-    ** may be lying around. Returning an error code won't help matters.
-    */
-    disable_simulated_io_errors();
-    sqlite3FaultBeginBenign(SQLITE_FAULTINJECTOR_MALLOC);
-    for(i=0; i<db->nDb; i++){ 
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        sqlite3BtreeCommitPhaseTwo(pBt);
-      }
+      return 0;
     }
-    sqlite3FaultEndBenign(SQLITE_FAULTINJECTOR_MALLOC);
-    enable_simulated_io_errors();
+  }
 
-    sqlite3VtabCommit(db);
+  if( i<0 ){
+    sqlite3Error(pErrorDb, SQLITE_ERROR, "unknown database %s", zDb);
+    return 0;
   }
-#endif
 
-  return rc;
+  return pDb->aDb[i].pBt;
 }
 
-/* 
-** This routine checks that the sqlite3.activeVdbeCnt count variable
-** matches the number of vdbe's in the list sqlite3.pVdbe that are
-** currently active. An assertion fails if the two counts do not match.
-** This is an internal self-check only - it is not an essential processing
-** step.
+/*
+** Create an sqlite3_backup process to copy the contents of zSrcDb from
+** connection handle pSrcDb to zDestDb in pDestDb. If successful, return
+** a pointer to the new sqlite3_backup object.
 **
-** This is a no-op if NDEBUG is defined.
+** If an error occurs, NULL is returned and an error code and error message
+** stored in database handle pDestDb.
 */
-#ifndef NDEBUG
-static void checkActiveVdbeCnt(sqlite3 *db){
-  Vdbe *p;
-  int cnt = 0;
-  p = db->pVdbe;
-  while( p ){
-    if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
-      cnt++;
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+  sqlite3* pDestDb,                     /* Database to write to */
+  const char *zDestDb,                  /* Name of database within pDestDb */
+  sqlite3* pSrcDb,                      /* Database connection to read from */
+  const char *zSrcDb                    /* Name of database within pSrcDb */
+){
+  sqlite3_backup *p;                    /* Value to return */
+
+  /* Lock the source database handle. The destination database
+  ** handle is not locked in this routine, but it is locked in
+  ** sqlite3_backup_step(). The user is required to ensure that no
+  ** other thread accesses the destination handle for the duration
+  ** of the backup operation.  Any attempt to use the destination
+  ** database connection while a backup is in progress may cause
+  ** a malfunction or a deadlock.
+  */
+  sqlite3_mutex_enter(pSrcDb->mutex);
+  sqlite3_mutex_enter(pDestDb->mutex);
+
+  if( pSrcDb==pDestDb ){
+    sqlite3Error(
+        pDestDb, SQLITE_ERROR, "source and destination must be distinct"
+    );
+    p = 0;
+  }else {
+    /* Allocate space for a new sqlite3_backup object */
+    p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
+    if( !p ){
+      sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
     }
-    p = p->pNext;
   }
-  assert( cnt==db->activeVdbeCnt );
+
+  /* If the allocation succeeded, populate the new object. */
+  if( p ){
+    memset(p, 0, sizeof(sqlite3_backup));
+    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
+    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
+    p->pDestDb = pDestDb;
+    p->pSrcDb = pSrcDb;
+    p->iNext = 1;
+    p->isAttached = 0;
+
+    if( 0==p->pSrc || 0==p->pDest ){
+      /* One (or both) of the named databases did not exist. An error has
+      ** already been written into the pDestDb handle. All that is left
+      ** to do here is free the sqlite3_backup structure.
+      */
+      sqlite3_free(p);
+      p = 0;
+    }
+  }
+  if( p ){
+    p->pSrc->nBackup++;
+  }
+
+  sqlite3_mutex_leave(pDestDb->mutex);
+  sqlite3_mutex_leave(pSrcDb->mutex);
+  return p;
 }
-#else
-#define checkActiveVdbeCnt(x)
-#endif
 
 /*
-** For every Btree that in database connection db which 
-** has been modified, "trip" or invalidate each cursor in
-** that Btree might have been modified so that the cursor
-** can never be used again.  This happens when a rollback
-*** occurs.  We have to trip all the other cursors, even
-** cursor from other VMs in different database connections,
-** so that none of them try to use the data at which they
-** were pointing and which now may have been changed due
-** to the rollback.
-**
-** Remember that a rollback can delete tables complete and
-** reorder rootpages.  So it is not sufficient just to save
-** the state of the cursor.  We have to invalidate the cursor
-** so that it is never used again.
+** Argument rc is an SQLite error code. Return true if this error is 
+** considered fatal if encountered during a backup operation. All errors
+** are considered fatal except for SQLITE_BUSY and SQLITE_LOCKED.
 */
-static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
-  int i;
-  for(i=0; i<db->nDb; i++){
-    Btree *p = db->aDb[i].pBt;
-    if( p && sqlite3BtreeIsInTrans(p) ){
-      sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
+static int isFatalError(int rc){
+  return (rc!=SQLITE_OK && rc!=SQLITE_BUSY && ALWAYS(rc!=SQLITE_LOCKED));
+}
+
+/*
+** Parameter zSrcData points to a buffer containing the data for 
+** page iSrcPg from the source database. Copy this data into the 
+** destination database.
+*/
+static int backupOnePage(sqlite3_backup *p, Pgno iSrcPg, const u8 *zSrcData){
+  Pager * const pDestPager = sqlite3BtreePager(p->pDest);
+  const int nSrcPgsz = sqlite3BtreeGetPageSize(p->pSrc);
+  int nDestPgsz = sqlite3BtreeGetPageSize(p->pDest);
+  const int nCopy = MIN(nSrcPgsz, nDestPgsz);
+  const i64 iEnd = (i64)iSrcPg*(i64)nSrcPgsz;
+
+  int rc = SQLITE_OK;
+  i64 iOff;
+
+  assert( p->bDestLocked );
+  assert( !isFatalError(p->rc) );
+  assert( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) );
+  assert( zSrcData );
+
+  /* Catch the case where the destination is an in-memory database and the
+  ** page sizes of the source and destination differ. 
+  */
+  if( nSrcPgsz!=nDestPgsz && sqlite3PagerIsMemdb(sqlite3BtreePager(p->pDest)) ){
+    rc = SQLITE_READONLY;
+  }
+
+  /* This loop runs once for each destination page spanned by the source 
+  ** page. For each iteration, variable iOff is set to the byte offset
+  ** of the destination page.
+  */
+  for(iOff=iEnd-(i64)nSrcPgsz; rc==SQLITE_OK && iOff<iEnd; iOff+=nDestPgsz){
+    DbPage *pDestPg = 0;
+    Pgno iDest = (Pgno)(iOff/nDestPgsz)+1;
+    if( iDest==PENDING_BYTE_PAGE(p->pDest->pBt) ) continue;
+    if( SQLITE_OK==(rc = sqlite3PagerGet(pDestPager, iDest, &pDestPg))
+     && SQLITE_OK==(rc = sqlite3PagerWrite(pDestPg))
+    ){
+      const u8 *zIn = &zSrcData[iOff%nSrcPgsz];
+      u8 *zDestData = sqlite3PagerGetData(pDestPg);
+      u8 *zOut = &zDestData[iOff%nDestPgsz];
+
+      /* Copy the data from the source page into the destination page.
+      ** Then clear the Btree layer MemPage.isInit flag. Both this module
+      ** and the pager code use this trick (clearing the first byte
+      ** of the page 'extra' space to invalidate the Btree layers
+      ** cached parse of the page). MemPage.isInit is marked 
+      ** "MUST BE FIRST" for this purpose.
+      */
+      memcpy(zOut, zIn, nCopy);
+      ((u8 *)sqlite3PagerGetExtra(pDestPg))[0] = 0;
     }
+    sqlite3PagerUnref(pDestPg);
   }
+
+  return rc;
 }
 
 /*
-** This routine is called the when a VDBE tries to halt.  If the VDBE
-** has made changes and is in autocommit mode, then commit those
-** changes.  If a rollback is needed, then do the rollback.
-**
-** This routine is the only way to move the state of a VM from
-** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT.  It is harmless to
-** call this on a VM that is in the SQLITE_MAGIC_HALT state.
+** If pFile is currently larger than iSize bytes, then truncate it to
+** exactly iSize bytes. If pFile is not larger than iSize bytes, then
+** this function is a no-op.
 **
-** Return an error code.  If the commit could not complete because of
-** lock contention, return SQLITE_BUSY.  If SQLITE_BUSY is returned, it
-** means the close did not happen and needs to be repeated.
+** Return SQLITE_OK if everything is successful, or an SQLite error 
+** code if an error occurs.
 */
-SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
-  sqlite3 *db = p->db;
-  int i;
-  int (*xFunc)(Btree *pBt) = 0;  /* Function to call on each btree backend */
-  int isSpecialError;            /* Set to true if SQLITE_NOMEM or IOERR */
+static int backupTruncateFile(sqlite3_file *pFile, i64 iSize){
+  i64 iCurrent;
+  int rc = sqlite3OsFileSize(pFile, &iCurrent);
+  if( rc==SQLITE_OK && iCurrent>iSize ){
+    rc = sqlite3OsTruncate(pFile, iSize);
+  }
+  return rc;
+}
 
-  /* This function contains the logic that determines if a statement or
-  ** transaction will be committed or rolled back as a result of the
-  ** execution of this virtual machine. 
-  **
-  ** If any of the following errors occur:
-  **
-  **     SQLITE_NOMEM
-  **     SQLITE_IOERR
-  **     SQLITE_FULL
-  **     SQLITE_INTERRUPT
-  **
-  ** Then the internal cache might have been left in an inconsistent
-  ** state.  We need to rollback the statement transaction, if there is
-  ** one, or the complete transaction if there is no statement transaction.
-  */
+/*
+** Register this backup object with the associated source pager for
+** callbacks when pages are changed or the cache invalidated.
+*/
+static void attachBackupObject(sqlite3_backup *p){
+  sqlite3_backup **pp;
+  assert( sqlite3BtreeHoldsMutex(p->pSrc) );
+  pp = sqlite3PagerBackupPtr(sqlite3BtreePager(p->pSrc));
+  p->pNext = *pp;
+  *pp = p;
+  p->isAttached = 1;
+}
 
-  if( p->db->mallocFailed ){
-    p->rc = SQLITE_NOMEM;
-  }
-  closeAllCursorsExceptActiveVtabs(p);
-  if( p->magic!=VDBE_MAGIC_RUN ){
-    return SQLITE_OK;
+/*
+** Copy nPage pages from the source b-tree to the destination.
+*/
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
+  int rc;
+
+  sqlite3_mutex_enter(p->pSrcDb->mutex);
+  sqlite3BtreeEnter(p->pSrc);
+  if( p->pDestDb ){
+    sqlite3_mutex_enter(p->pDestDb->mutex);
   }
-  checkActiveVdbeCnt(db);
 
-  /* No commit or rollback needed if the program never started */
-  if( p->pc>=0 ){
-    int mrc;   /* Primary error code from p->rc */
+  rc = p->rc;
+  if( !isFatalError(rc) ){
+    Pager * const pSrcPager = sqlite3BtreePager(p->pSrc);     /* Source pager */
+    Pager * const pDestPager = sqlite3BtreePager(p->pDest);   /* Dest pager */
+    int ii;                            /* Iterator variable */
+    int nSrcPage = -1;                 /* Size of source db in pages */
+    int bCloseTrans = 0;               /* True if src db requires unlocking */
 
-    /* Lock all btrees used by the statement */
-    sqlite3BtreeMutexArrayEnter(&p->aMutex);
+    /* If the source pager is currently in a write-transaction, return
+    ** SQLITE_BUSY immediately.
+    */
+    if( p->pDestDb && p->pSrc->pBt->inTransaction==TRANS_WRITE ){
+      rc = SQLITE_BUSY;
+    }else{
+      rc = SQLITE_OK;
+    }
 
-    /* Check for one of the special errors */
-    mrc = p->rc & 0xff;
-    isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
-                     || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
-    if( isSpecialError ){
-      /* This loop does static analysis of the query to see which of the
-      ** following three categories it falls into:
-      **
-      **     Read-only
-      **     Query with statement journal
-      **     Query without statement journal
-      **
-      ** We could do something more elegant than this static analysis (i.e.
-      ** store the type of query as part of the compliation phase), but 
-      ** handling malloc() or IO failure is a fairly obscure edge case so 
-      ** this is probably easier. Todo: Might be an opportunity to reduce 
-      ** code size a very small amount though...
-      */
-      int notReadOnly = 0;
-      int isStatement = 0;
-      assert(p->aOp || p->nOp==0);
-      for(i=0; i<p->nOp; i++){ 
-        switch( p->aOp[i].opcode ){
-          case OP_Transaction:
-            notReadOnly |= p->aOp[i].p2;
-            break;
-          case OP_Statement:
-            isStatement = 1;
-            break;
-        }
-      }
+    /* Lock the destination database, if it is not locked already. */
+    if( SQLITE_OK==rc && p->bDestLocked==0
+     && SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2)) 
+    ){
+      p->bDestLocked = 1;
+      sqlite3BtreeGetMeta(p->pDest, BTREE_SCHEMA_VERSION, &p->iDestSchema);
+    }
 
-   
-      /* If the query was read-only, we need do no rollback at all. Otherwise,
-      ** proceed with the special handling.
-      */
-      if( notReadOnly || mrc!=SQLITE_INTERRUPT ){
-        if( p->rc==SQLITE_IOERR_BLOCKED && isStatement ){
-          xFunc = sqlite3BtreeRollbackStmt;
-          p->rc = SQLITE_BUSY;
-        } else if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && isStatement ){
-          xFunc = sqlite3BtreeRollbackStmt;
-        }else{
-          /* We are forced to roll back the active transaction. Before doing
-          ** so, abort any other statements this handle currently has active.
-          */
-          invalidateCursorsOnModifiedBtrees(db);
-          sqlite3RollbackAll(db);
-          db->autoCommit = 1;
+    /* If there is no open read-transaction on the source database, open
+    ** one now. If a transaction is opened here, then it will be closed
+    ** before this function exits.
+    */
+    if( rc==SQLITE_OK && 0==sqlite3BtreeIsInReadTrans(p->pSrc) ){
+      rc = sqlite3BtreeBeginTrans(p->pSrc, 0);
+      bCloseTrans = 1;
+    }
+  
+    /* Now that there is a read-lock on the source database, query the
+    ** source pager for the number of pages in the database.
+    */
+    if( rc==SQLITE_OK ){
+      rc = sqlite3PagerPagecount(pSrcPager, &nSrcPage);
+    }
+    for(ii=0; (nPage<0 || ii<nPage) && p->iNext<=(Pgno)nSrcPage && !rc; ii++){
+      const Pgno iSrcPg = p->iNext;                 /* Source page number */
+      if( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) ){
+        DbPage *pSrcPg;                             /* Source page object */
+        rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg);
+        if( rc==SQLITE_OK ){
+          rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg));
+          sqlite3PagerUnref(pSrcPg);
         }
       }
+      p->iNext++;
+    }
+    if( rc==SQLITE_OK ){
+      p->nPagecount = nSrcPage;
+      p->nRemaining = nSrcPage+1-p->iNext;
+      if( p->iNext>(Pgno)nSrcPage ){
+        rc = SQLITE_DONE;
+      }else if( !p->isAttached ){
+        attachBackupObject(p);
+      }
     }
   
-    /* If the auto-commit flag is set and this is the only active vdbe, then
-    ** we do either a commit or rollback of the current transaction. 
-    **
-    ** Note: This block also runs if one of the special errors handled 
-    ** above has occured. 
+    /* Update the schema version field in the destination database. This
+    ** is to make sure that the schema-version really does change in
+    ** the case where the source and destination databases have the
+    ** same schema version.
     */
-    if( db->autoCommit && db->activeVdbeCnt==1 ){
-      if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
-        /* The auto-commit flag is true, and the vdbe program was 
-        ** successful or hit an 'OR FAIL' constraint. This means a commit 
-        ** is required.
-        */
-        int rc = vdbeCommit(db);
-        if( rc==SQLITE_BUSY ){
-          sqlite3BtreeMutexArrayLeave(&p->aMutex);
-          return SQLITE_BUSY;
-        }else if( rc!=SQLITE_OK ){
-          p->rc = rc;
-          sqlite3RollbackAll(db);
-        }else{
-          sqlite3CommitInternalChanges(db);
+    if( rc==SQLITE_DONE 
+     && (rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1))==SQLITE_OK
+    ){
+      const int nSrcPagesize = sqlite3BtreeGetPageSize(p->pSrc);
+      const int nDestPagesize = sqlite3BtreeGetPageSize(p->pDest);
+      int nDestTruncate;
+  
+      if( p->pDestDb ){
+        sqlite3ResetInternalSchema(p->pDestDb, 0);
+      }
+
+      /* Set nDestTruncate to the final number of pages in the destination
+      ** database. The complication here is that the destination page
+      ** size may be different to the source page size. 
+      **
+      ** If the source page size is smaller than the destination page size, 
+      ** round up. In this case the call to sqlite3OsTruncate() below will
+      ** fix the size of the file. However it is important to call
+      ** sqlite3PagerTruncateImage() here so that any pages in the 
+      ** destination file that lie beyond the nDestTruncate page mark are
+      ** journalled by PagerCommitPhaseOne() before they are destroyed
+      ** by the file truncation.
+      */
+      if( nSrcPagesize<nDestPagesize ){
+        int ratio = nDestPagesize/nSrcPagesize;
+        nDestTruncate = (nSrcPage+ratio-1)/ratio;
+        if( nDestTruncate==(int)PENDING_BYTE_PAGE(p->pDest->pBt) ){
+          nDestTruncate--;
         }
       }else{
-        sqlite3RollbackAll(db);
+        nDestTruncate = nSrcPage * (nSrcPagesize/nDestPagesize);
       }
-    }else if( !xFunc ){
-      if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
-        if( p->openedStatement ){
-          xFunc = sqlite3BtreeCommitStmt;
-        } 
-      }else if( p->errorAction==OE_Abort ){
-        xFunc = sqlite3BtreeRollbackStmt;
+      sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
+
+      if( nSrcPagesize<nDestPagesize ){
+        /* If the source page-size is smaller than the destination page-size,
+        ** two extra things may need to happen:
+        **
+        **   * The destination may need to be truncated, and
+        **
+        **   * Data stored on the pages immediately following the 
+        **     pending-byte page in the source database may need to be
+        **     copied into the destination database.
+        */
+        const i64 iSize = (i64)nSrcPagesize * (i64)nSrcPage;
+        sqlite3_file * const pFile = sqlite3PagerFile(pDestPager);
+
+        assert( pFile );
+        assert( (i64)nDestTruncate*(i64)nDestPagesize >= iSize || (
+              nDestTruncate==(int)(PENDING_BYTE_PAGE(p->pDest->pBt)-1)
+           && iSize>=PENDING_BYTE && iSize<=PENDING_BYTE+nDestPagesize
+        ));
+        if( SQLITE_OK==(rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1))
+         && SQLITE_OK==(rc = backupTruncateFile(pFile, iSize))
+         && SQLITE_OK==(rc = sqlite3PagerSync(pDestPager))
+        ){
+          i64 iOff;
+          i64 iEnd = MIN(PENDING_BYTE + nDestPagesize, iSize);
+          for(
+            iOff=PENDING_BYTE+nSrcPagesize; 
+            rc==SQLITE_OK && iOff<iEnd; 
+            iOff+=nSrcPagesize
+          ){
+            PgHdr *pSrcPg = 0;
+            const Pgno iSrcPg = (Pgno)((iOff/nSrcPagesize)+1);
+            rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg);
+            if( rc==SQLITE_OK ){
+              u8 *zData = sqlite3PagerGetData(pSrcPg);
+              rc = sqlite3OsWrite(pFile, zData, nSrcPagesize, iOff);
+            }
+            sqlite3PagerUnref(pSrcPg);
+          }
+        }
       }else{
-        invalidateCursorsOnModifiedBtrees(db);
-        sqlite3RollbackAll(db);
-        db->autoCommit = 1;
+        rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0);
       }
-    }
   
-    /* If xFunc is not NULL, then it is one of sqlite3BtreeRollbackStmt or
-    ** sqlite3BtreeCommitStmt. Call it once on each backend. If an error occurs
-    ** and the return code is still SQLITE_OK, set the return code to the new
-    ** error value.
-    */
-    assert(!xFunc ||
-      xFunc==sqlite3BtreeCommitStmt ||
-      xFunc==sqlite3BtreeRollbackStmt
-    );
-    for(i=0; xFunc && i<db->nDb; i++){ 
-      int rc;
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        rc = xFunc(pBt);
-        if( rc && (p->rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT) ){
-          p->rc = rc;
-          sqlite3SetString(&p->zErrMsg, 0);
-        }
+      /* Finish committing the transaction to the destination database. */
+      if( SQLITE_OK==rc
+       && SQLITE_OK==(rc = sqlite3BtreeCommitPhaseTwo(p->pDest))
+      ){
+        rc = SQLITE_DONE;
       }
     }
   
-    /* If this was an INSERT, UPDATE or DELETE and the statement was committed, 
-    ** set the change counter. 
+    /* If bCloseTrans is true, then this function opened a read transaction
+    ** on the source database. Close the read transaction here. There is
+    ** no need to check the return values of the btree methods here, as
+    ** "committing" a read-only transaction cannot fail.
     */
-    if( p->changeCntOn && p->pc>=0 ){
-      if( !xFunc || xFunc==sqlite3BtreeCommitStmt ){
-        sqlite3VdbeSetChanges(db, p->nChange);
-      }else{
-        sqlite3VdbeSetChanges(db, 0);
-      }
-      p->nChange = 0;
+    if( bCloseTrans ){
+      TESTONLY( int rc2 );
+      TESTONLY( rc2  = ) sqlite3BtreeCommitPhaseOne(p->pSrc, 0);
+      TESTONLY( rc2 |= ) sqlite3BtreeCommitPhaseTwo(p->pSrc);
+      assert( rc2==SQLITE_OK );
     }
   
-    /* Rollback or commit any schema changes that occurred. */
-    if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
-      sqlite3ResetInternalSchema(db, 0);
-      db->flags = (db->flags | SQLITE_InternChanges);
-    }
-
-    /* Release the locks */
-    sqlite3BtreeMutexArrayLeave(&p->aMutex);
-  }
-
-  /* We have successfully halted and closed the VM.  Record this fact. */
-  if( p->pc>=0 ){
-    db->activeVdbeCnt--;
+    p->rc = rc;
   }
-  p->magic = VDBE_MAGIC_HALT;
-  checkActiveVdbeCnt(db);
-  if( p->db->mallocFailed ){
-    p->rc = SQLITE_NOMEM;
+  if( p->pDestDb ){
+    sqlite3_mutex_leave(p->pDestDb->mutex);
   }
-
-  return SQLITE_OK;
-}
-
-
-/*
-** Each VDBE holds the result of the most recent sqlite3_step() call
-** in p->rc.  This routine sets that result back to SQLITE_OK.
-*/
-SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe *p){
-  p->rc = SQLITE_OK;
+  sqlite3BtreeLeave(p->pSrc);
+  sqlite3_mutex_leave(p->pSrcDb->mutex);
+  return rc;
 }
 
 /*
-** Clean up a VDBE after execution but do not delete the VDBE just yet.
-** Write any error messages into *pzErrMsg.  Return the result code.
-**
-** After this routine is run, the VDBE should be ready to be executed
-** again.
-**
-** To look at it another way, this routine resets the state of the
-** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
-** VDBE_MAGIC_INIT.
+** Release all resources associated with an sqlite3_backup* handle.
 */
-SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe *p, int freebuffers){
-  sqlite3 *db;
-  db = p->db;
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p){
+  sqlite3_backup **pp;                 /* Ptr to head of pagers backup list */
+  sqlite3_mutex *mutex;                /* Mutex to protect source database */
+  int rc;                              /* Value to return */
 
-  /* If the VM did not run to completion or if it encountered an
-  ** error, then it might not have been halted properly.  So halt
-  ** it now.
-  */
-  (void)sqlite3SafetyOn(db);
-  sqlite3VdbeHalt(p);
-  (void)sqlite3SafetyOff(db);
+  /* Enter the mutexes */
+  if( p==0 ) return SQLITE_OK;
+  sqlite3_mutex_enter(p->pSrcDb->mutex);
+  sqlite3BtreeEnter(p->pSrc);
+  mutex = p->pSrcDb->mutex;
+  if( p->pDestDb ){
+    sqlite3_mutex_enter(p->pDestDb->mutex);
+  }
 
-  /* If the VDBE has be run even partially, then transfer the error code
-  ** and error message from the VDBE into the main database structure.  But
-  ** if the VDBE has just been set to run but has not actually executed any
-  ** instructions yet, leave the main database error information unchanged.
-  */
-  if( p->pc>=0 ){
-    if( p->zErrMsg ){
-      sqlite3ValueSetStr(db->pErr,-1,p->zErrMsg,SQLITE_UTF8,sqlite3_free);
-      db->errCode = p->rc;
-      p->zErrMsg = 0;
-    }else if( p->rc ){
-      sqlite3Error(db, p->rc, 0);
-    }else{
-      sqlite3Error(db, SQLITE_OK, 0);
+  /* Detach this backup from the source pager. */
+  if( p->pDestDb ){
+    p->pSrc->nBackup--;
+  }
+  if( p->isAttached ){
+    pp = sqlite3PagerBackupPtr(sqlite3BtreePager(p->pSrc));
+    while( *pp!=p ){
+      pp = &(*pp)->pNext;
     }
-  }else if( p->rc && p->expired ){
-    /* The expired flag was set on the VDBE before the first call
-    ** to sqlite3_step(). For consistency (since sqlite3_step() was
-    ** called), set the database error in this case as well.
-    */
-    sqlite3Error(db, p->rc, 0);
-    sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, sqlite3_free);
-    p->zErrMsg = 0;
+    *pp = p->pNext;
   }
 
-  /* Reclaim all memory used by the VDBE
-  */
-  Cleanup(p, freebuffers);
+  /* If a transaction is still open on the Btree, roll it back. */
+  sqlite3BtreeRollback(p->pDest);
 
-  /* Save profiling information from this VDBE run.
-  */
-#ifdef VDBE_PROFILE
-  {
-    FILE *out = fopen("vdbe_profile.out", "a");
-    if( out ){
-      int i;
-      fprintf(out, "---- ");
-      for(i=0; i<p->nOp; i++){
-        fprintf(out, "%02x", p->aOp[i].opcode);
-      }
-      fprintf(out, "\n");
-      for(i=0; i<p->nOp; i++){
-        fprintf(out, "%6d %10lld %8lld ",
-           p->aOp[i].cnt,
-           p->aOp[i].cycles,
-           p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
-        );
-        sqlite3VdbePrintOp(out, i, &p->aOp[i]);
-      }
-      fclose(out);
-    }
+  /* Set the error code of the destination database handle. */
+  rc = (p->rc==SQLITE_DONE) ? SQLITE_OK : p->rc;
+  sqlite3Error(p->pDestDb, rc, 0);
+
+  /* Exit the mutexes and free the backup context structure. */
+  if( p->pDestDb ){
+    sqlite3_mutex_leave(p->pDestDb->mutex);
   }
-#endif
-  p->magic = VDBE_MAGIC_INIT;
-  p->aborted = 0;
-  return p->rc & db->errMask;
+  sqlite3BtreeLeave(p->pSrc);
+  if( p->pDestDb ){
+    sqlite3_free(p);
+  }
+  sqlite3_mutex_leave(mutex);
+  return rc;
 }
- 
+
 /*
-** Clean up and delete a VDBE after execution.  Return an integer which is
-** the result code.  Write any error message text into *pzErrMsg.
+** Return the number of pages still to be backed up as of the most recent
+** call to sqlite3_backup_step().
 */
-SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe *p){
-  int rc = SQLITE_OK;
-  if( p->magic==VDBE_MAGIC_RUN || p->magic==VDBE_MAGIC_HALT ){
-    rc = sqlite3VdbeReset(p, 1);
-    assert( (rc & p->db->errMask)==rc );
-  }else if( p->magic!=VDBE_MAGIC_INIT ){
-    return SQLITE_MISUSE;
-  }
-  releaseMemArray(&p->aMem[1], p->nMem, 1);
-  sqlite3VdbeDelete(p);
-  return rc;
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p){
+  return p->nRemaining;
 }
 
 /*
-** Call the destructor for each auxdata entry in pVdbeFunc for which
-** the corresponding bit in mask is clear.  Auxdata entries beyond 31
-** are always destroyed.  To destroy all auxdata entries, call this
-** routine with mask==0.
+** Return the total number of pages in the source database as of the most 
+** recent call to sqlite3_backup_step().
 */
-SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
-  int i;
-  for(i=0; i<pVdbeFunc->nAux; i++){
-    struct AuxData *pAux = &pVdbeFunc->apAux[i];
-    if( (i>31 || !(mask&(1<<i))) && pAux->pAux ){
-      if( pAux->xDelete ){
-        pAux->xDelete(pAux->pAux);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p){
+  return p->nPagecount;
+}
+
+/*
+** This function is called after the contents of page iPage of the
+** source database have been modified. If page iPage has already been 
+** copied into the destination database, then the data written to the
+** destination is now invalidated. The destination copy of iPage needs
+** to be updated with the new data before the backup operation is
+** complete.
+**
+** It is assumed that the mutex associated with the BtShared object
+** corresponding to the source database is held when this function is
+** called.
+*/
+SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *pBackup, Pgno iPage, const u8 *aData){
+  sqlite3_backup *p;                   /* Iterator variable */
+  for(p=pBackup; p; p=p->pNext){
+    assert( sqlite3_mutex_held(p->pSrc->pBt->mutex) );
+    if( !isFatalError(p->rc) && iPage<p->iNext ){
+      /* The backup process p has already copied page iPage. But now it
+      ** has been modified by a transaction on the source pager. Copy
+      ** the new data into the backup.
+      */
+      int rc = backupOnePage(p, iPage, aData);
+      assert( rc!=SQLITE_BUSY && rc!=SQLITE_LOCKED );
+      if( rc!=SQLITE_OK ){
+        p->rc = rc;
       }
-      pAux->pAux = 0;
     }
   }
 }
 
 /*
-** Delete an entire VDBE.
+** Restart the backup process. This is called when the pager layer
+** detects that the database has been modified by an external database
+** connection. In this case there is no way of knowing which of the
+** pages that have been copied into the destination database are still 
+** valid and which are not, so the entire process needs to be restarted.
+**
+** It is assumed that the mutex associated with the BtShared object
+** corresponding to the source database is held when this function is
+** called.
 */
-SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
-  int i;
-  if( p==0 ) return;
-  Cleanup(p, 1);
-  if( p->pPrev ){
-    p->pPrev->pNext = p->pNext;
-  }else{
-    assert( p->db->pVdbe==p );
-    p->db->pVdbe = p->pNext;
-  }
-  if( p->pNext ){
-    p->pNext->pPrev = p->pPrev;
-  }
-  if( p->aOp ){
-    Op *pOp = p->aOp;
-    for(i=0; i<p->nOp; i++, pOp++){
-      freeP4(pOp->p4type, pOp->p4.p);
-#ifdef SQLITE_DEBUG
-      sqlite3_free(pOp->zComment);
-#endif     
-    }
-    sqlite3_free(p->aOp);
-  }
-  releaseMemArray(p->aVar, p->nVar, 1);
-  sqlite3_free(p->aLabel);
-  if( p->aMem ){
-    sqlite3_free(&p->aMem[1]);
+SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *pBackup){
+  sqlite3_backup *p;                   /* Iterator variable */
+  for(p=pBackup; p; p=p->pNext){
+    assert( sqlite3_mutex_held(p->pSrc->pBt->mutex) );
+    p->iNext = 1;
   }
-  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N, 1);
-  sqlite3_free(p->aColName);
-  sqlite3_free(p->zSql);
-  p->magic = VDBE_MAGIC_DEAD;
-  sqlite3_free(p);
 }
 
+#ifndef SQLITE_OMIT_VACUUM
 /*
-** If a MoveTo operation is pending on the given cursor, then do that
-** MoveTo now.  Return an error code.  If no MoveTo is pending, this
-** routine does nothing and returns SQLITE_OK.
+** Copy the complete content of pBtFrom into pBtTo.  A transaction
+** must be active for both files.
+**
+** The size of file pTo may be reduced by this operation. If anything 
+** goes wrong, the transaction on pTo is rolled back. If successful, the 
+** transaction is committed before returning.
 */
-SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(Cursor *p){
-  if( p->deferredMoveto ){
-    int res, rc;
-#ifdef SQLITE_TEST
-    extern int sqlite3_search_count;
-#endif
-    assert( p->isTable );
-    rc = sqlite3BtreeMoveto(p->pCursor, 0, 0, p->movetoTarget, 0, &res);
-    if( rc ) return rc;
-    *p->pIncrKey = 0;
-    p->lastRowid = keyToInt(p->movetoTarget);
-    p->rowidIsValid = res==0;
-    if( res<0 ){
-      rc = sqlite3BtreeNext(p->pCursor, &res);
-      if( rc ) return rc;
-    }
-#ifdef SQLITE_TEST
-    sqlite3_search_count++;
-#endif
-    p->deferredMoveto = 0;
-    p->cacheStatus = CACHE_STALE;
+SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
+  int rc;
+  sqlite3_backup b;
+  sqlite3BtreeEnter(pTo);
+  sqlite3BtreeEnter(pFrom);
+
+  /* Set up an sqlite3_backup object. sqlite3_backup.pDestDb must be set
+  ** to 0. This is used by the implementations of sqlite3_backup_step()
+  ** and sqlite3_backup_finish() to detect that they are being called
+  ** from this function, not directly by the user.
+  */
+  memset(&b, 0, sizeof(b));
+  b.pSrcDb = pFrom->db;
+  b.pSrc = pFrom;
+  b.pDest = pTo;
+  b.iNext = 1;
+
+  /* 0x7FFFFFFF is the hard limit for the number of pages in a database
+  ** file. By passing this as the number of pages to copy to
+  ** sqlite3_backup_step(), we can guarantee that the copy finishes 
+  ** within a single call (unless an error occurs). The assert() statement
+  ** checks this assumption - (p->rc) should be set to either SQLITE_DONE 
+  ** or an error code.
+  */
+  sqlite3_backup_step(&b, 0x7FFFFFFF);
+  assert( b.rc!=SQLITE_OK );
+  rc = sqlite3_backup_finish(&b);
+  if( rc==SQLITE_OK ){
+    pTo->pBt->pageSizeFixed = 0;
   }
-  return SQLITE_OK;
+
+  sqlite3BtreeLeave(pFrom);
+  sqlite3BtreeLeave(pTo);
+  return rc;
 }
+#endif /* SQLITE_OMIT_VACUUM */
 
+/************** End of backup.c **********************************************/
+/************** Begin file vdbemem.c *****************************************/
 /*
-** The following functions:
-**
-** sqlite3VdbeSerialType()
-** sqlite3VdbeSerialTypeLen()
-** sqlite3VdbeSerialRead()
-** sqlite3VdbeSerialLen()
-** sqlite3VdbeSerialWrite()
+** 2004 May 26
 **
-** encapsulate the code that serializes values for storage in SQLite
-** data and index records. Each serialized value consists of a
-** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
-** integer, stored as a varint.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** In an SQLite index record, the serial type is stored directly before
-** the blob of data that it corresponds to. In a table record, all serial
-** types are stored at the start of the record, and the blobs of data at
-** the end. Hence these functions allow the caller to handle the
-** serial-type and data blob seperately.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** The following table describes the various storage classes for data:
+*************************************************************************
 **
-**   serial type        bytes of data      type
-**   --------------     ---------------    ---------------
-**      0                     0            NULL
-**      1                     1            signed integer
-**      2                     2            signed integer
-**      3                     3            signed integer
-**      4                     4            signed integer
-**      5                     6            signed integer
-**      6                     8            signed integer
-**      7                     8            IEEE float
-**      8                     0            Integer constant 0
-**      9                     0            Integer constant 1
-**     10,11                               reserved for expansion
-**    N>=12 and even       (N-12)/2        BLOB
-**    N>=13 and odd        (N-13)/2        text
+** This file contains code use to manipulate "Mem" structure.  A "Mem"
+** stores a single value in the VDBE.  Mem is an opaque structure visible
+** only within the VDBE.  Interface routines refer to a Mem using the
+** name sqlite_value
 **
-** The 8 and 9 types were added in 3.3.0, file format 4.  Prior versions
-** of SQLite will not understand those serial types.
+** $Id: vdbemem.c,v 1.152 2009/07/22 18:07:41 drh Exp $
 */
 
 /*
-** Return the serial-type for the value stored in pMem.
+** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
+** P if required.
 */
-SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
-  int flags = pMem->flags;
-  int n;
+#define expandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
 
-  if( flags&MEM_Null ){
-    return 0;
+/*
+** If pMem is an object with a valid string representation, this routine
+** ensures the internal encoding for the string representation is
+** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
+**
+** If pMem is not a string object, or the encoding of the string
+** representation is already stored using the requested encoding, then this
+** routine is a no-op.
+**
+** SQLITE_OK is returned if the conversion is successful (or not required).
+** SQLITE_NOMEM may be returned if a malloc() fails during conversion
+** between formats.
+*/
+SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *pMem, int desiredEnc){
+  int rc;
+  assert( (pMem->flags&MEM_RowSet)==0 );
+  assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE
+           || desiredEnc==SQLITE_UTF16BE );
+  if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){
+    return SQLITE_OK;
   }
-  if( flags&MEM_Int ){
-    /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
-#   define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
-    i64 i = pMem->u.i;
-    u64 u;
-    if( file_format>=4 && (i&1)==i ){
-      return 8+i;
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+#ifdef SQLITE_OMIT_UTF16
+  return SQLITE_ERROR;
+#else
+
+  /* MemTranslate() may return SQLITE_OK or SQLITE_NOMEM. If NOMEM is returned,
+  ** then the encoding of the value may not have changed.
+  */
+  rc = sqlite3VdbeMemTranslate(pMem, (u8)desiredEnc);
+  assert(rc==SQLITE_OK    || rc==SQLITE_NOMEM);
+  assert(rc==SQLITE_OK    || pMem->enc!=desiredEnc);
+  assert(rc==SQLITE_NOMEM || pMem->enc==desiredEnc);
+  return rc;
+#endif
+}
+
+/*
+** Make sure pMem->z points to a writable allocation of at least 
+** n bytes.
+**
+** If the memory cell currently contains string or blob data
+** and the third argument passed to this function is true, the 
+** current content of the cell is preserved. Otherwise, it may
+** be discarded.  
+**
+** This function sets the MEM_Dyn flag and clears any xDel callback.
+** It also clears MEM_Ephem and MEM_Static. If the preserve flag is 
+** not set, Mem.n is zeroed.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve){
+  assert( 1 >=
+    ((pMem->zMalloc && pMem->zMalloc==pMem->z) ? 1 : 0) +
+    (((pMem->flags&MEM_Dyn)&&pMem->xDel) ? 1 : 0) + 
+    ((pMem->flags&MEM_Ephem) ? 1 : 0) + 
+    ((pMem->flags&MEM_Static) ? 1 : 0)
+  );
+  assert( (pMem->flags&MEM_RowSet)==0 );
+
+  if( n<32 ) n = 32;
+  if( sqlite3DbMallocSize(pMem->db, pMem->zMalloc)<n ){
+    if( preserve && pMem->z==pMem->zMalloc ){
+      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
+      preserve = 0;
+    }else{
+      sqlite3DbFree(pMem->db, pMem->zMalloc);
+      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
     }
-    u = i<0 ? -i : i;
-    if( u<=127 ) return 1;
-    if( u<=32767 ) return 2;
-    if( u<=8388607 ) return 3;
-    if( u<=2147483647 ) return 4;
-    if( u<=MAX_6BYTE ) return 5;
-    return 6;
   }
-  if( flags&MEM_Real ){
-    return 7;
+
+  if( pMem->z && preserve && pMem->zMalloc && pMem->z!=pMem->zMalloc ){
+    memcpy(pMem->zMalloc, pMem->z, pMem->n);
   }
-  assert( flags&(MEM_Str|MEM_Blob) );
-  n = pMem->n;
-  if( flags & MEM_Zero ){
-    n += pMem->u.i;
+  if( pMem->flags&MEM_Dyn && pMem->xDel ){
+    pMem->xDel((void *)(pMem->z));
   }
-  assert( n>=0 );
-  return ((n*2) + 12 + ((flags&MEM_Str)!=0));
+
+  pMem->z = pMem->zMalloc;
+  if( pMem->z==0 ){
+    pMem->flags = MEM_Null;
+  }else{
+    pMem->flags &= ~(MEM_Ephem|MEM_Static);
+  }
+  pMem->xDel = 0;
+  return (pMem->z ? SQLITE_OK : SQLITE_NOMEM);
 }
 
 /*
-** Return the length of the data corresponding to the supplied serial-type.
+** Make the given Mem object MEM_Dyn.  In other words, make it so
+** that any TEXT or BLOB content is stored in memory obtained from
+** malloc().  In this way, we know that the memory is safe to be
+** overwritten or altered.
+**
+** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
 */
-SQLITE_PRIVATE int sqlite3VdbeSerialTypeLen(u32 serial_type){
-  if( serial_type>=12 ){
-    return (serial_type-12)/2;
-  }else{
-    static const u8 aSize[] = { 0, 1, 2, 3, 4, 6, 8, 8, 0, 0, 0, 0 };
-    return aSize[serial_type];
+SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem *pMem){
+  int f;
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( (pMem->flags&MEM_RowSet)==0 );
+  expandBlob(pMem);
+  f = pMem->flags;
+  if( (f&(MEM_Str|MEM_Blob)) && pMem->z!=pMem->zMalloc ){
+    if( sqlite3VdbeMemGrow(pMem, pMem->n + 2, 1) ){
+      return SQLITE_NOMEM;
+    }
+    pMem->z[pMem->n] = 0;
+    pMem->z[pMem->n+1] = 0;
+    pMem->flags |= MEM_Term;
   }
+
+  return SQLITE_OK;
 }
 
 /*
-** If we are on an architecture with mixed-endian floating 
-** points (ex: ARM7) then swap the lower 4 bytes with the 
-** upper 4 bytes.  Return the result.
-**
-** For most architectures, this is a no-op.
-**
-** (later):  It is reported to me that the mixed-endian problem
-** on ARM7 is an issue with GCC, not with the ARM7 chip.  It seems
-** that early versions of GCC stored the two words of a 64-bit
-** float in the wrong order.  And that error has been propagated
-** ever since.  The blame is not necessarily with GCC, though.
-** GCC might have just copying the problem from a prior compiler.
-** I am also told that newer versions of GCC that follow a different
-** ABI get the byte order right.
-**
-** Developers using SQLite on an ARM7 should compile and run their
-** application using -DSQLITE_DEBUG=1 at least once.  With DEBUG
-** enabled, some asserts below will ensure that the byte order of
-** floating point values is correct.
-**
-** (2007-08-30)  Frank van Vugt has studied this problem closely
-** and has send his findings to the SQLite developers.  Frank
-** writes that some Linux kernels offer floating point hardware
-** emulation that uses only 32-bit mantissas instead of a full 
-** 48-bits as required by the IEEE standard.  (This is the
-** CONFIG_FPE_FASTFPE option.)  On such systems, floating point
-** byte swapping becomes very complicated.  To avoid problems,
-** the necessary byte swapping is carried out using a 64-bit integer
-** rather than a 64-bit float.  Frank assures us that the code here
-** works for him.  We, the developers, have no way to independently
-** verify this, but Frank seems to know what he is talking about
-** so we trust him.
+** If the given Mem* has a zero-filled tail, turn it into an ordinary
+** blob stored in dynamically allocated space.
 */
-#ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
-static u64 floatSwap(u64 in){
-  union {
-    u64 r;
-    u32 i[2];
-  } u;
-  u32 t;
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE int sqlite3VdbeMemExpandBlob(Mem *pMem){
+  if( pMem->flags & MEM_Zero ){
+    int nByte;
+    assert( pMem->flags&MEM_Blob );
+    assert( (pMem->flags&MEM_RowSet)==0 );
+    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
 
-  u.r = in;
-  t = u.i[0];
-  u.i[0] = u.i[1];
-  u.i[1] = t;
-  return u.r;
+    /* Set nByte to the number of bytes required to store the expanded blob. */
+    nByte = pMem->n + pMem->u.nZero;
+    if( nByte<=0 ){
+      nByte = 1;
+    }
+    if( sqlite3VdbeMemGrow(pMem, nByte, 1) ){
+      return SQLITE_NOMEM;
+    }
+
+    memset(&pMem->z[pMem->n], 0, pMem->u.nZero);
+    pMem->n += pMem->u.nZero;
+    pMem->flags &= ~(MEM_Zero|MEM_Term);
+  }
+  return SQLITE_OK;
 }
-# define swapMixedEndianFloat(X)  X = floatSwap(X)
-#else
-# define swapMixedEndianFloat(X)
 #endif
 
+
 /*
-** Write the serialized data blob for the value stored in pMem into 
-** buf. It is assumed that the caller has allocated sufficient space.
-** Return the number of bytes written.
+** Make sure the given Mem is \u0000 terminated.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem *pMem){
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  if( (pMem->flags & MEM_Term)!=0 || (pMem->flags & MEM_Str)==0 ){
+    return SQLITE_OK;   /* Nothing to do */
+  }
+  if( sqlite3VdbeMemGrow(pMem, pMem->n+2, 1) ){
+    return SQLITE_NOMEM;
+  }
+  pMem->z[pMem->n] = 0;
+  pMem->z[pMem->n+1] = 0;
+  pMem->flags |= MEM_Term;
+  return SQLITE_OK;
+}
+
+/*
+** Add MEM_Str to the set of representations for the given Mem.  Numbers
+** are converted using sqlite3_snprintf().  Converting a BLOB to a string
+** is a no-op.
 **
-** nBuf is the amount of space left in buf[].  nBuf must always be
-** large enough to hold the entire field.  Except, if the field is
-** a blob with a zero-filled tail, then buf[] might be just the right
-** size to hold everything except for the zero-filled tail.  If buf[]
-** is only big enough to hold the non-zero prefix, then only write that
-** prefix into buf[].  But if buf[] is large enough to hold both the
-** prefix and the tail then write the prefix and set the tail to all
-** zeros.
+** Existing representations MEM_Int and MEM_Real are *not* invalidated.
 **
-** Return the number of bytes actually written into buf[].  The number
-** of bytes in the zero-filled tail is included in the return value only
-** if those bytes were zeroed in buf[].
-*/ 
-SQLITE_PRIVATE int sqlite3VdbeSerialPut(u8 *buf, int nBuf, Mem *pMem, int file_format){
-  u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
-  int len;
+** A MEM_Null value will never be passed to this function. This function is
+** used for converting values to text for returning to the user (i.e. via
+** sqlite3_value_text()), or for ensuring that values to be used as btree
+** keys are strings. In the former case a NULL pointer is returned the
+** user and the later is an internal programming error.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem *pMem, int enc){
+  int rc = SQLITE_OK;
+  int fg = pMem->flags;
+  const int nByte = 32;
 
-  /* Integer and Real */
-  if( serial_type<=7 && serial_type>0 ){
-    u64 v;
-    int i;
-    if( serial_type==7 ){
-      assert( sizeof(v)==sizeof(pMem->r) );
-      memcpy(&v, &pMem->r, sizeof(v));
-      swapMixedEndianFloat(v);
-    }else{
-      v = pMem->u.i;
-    }
-    len = i = sqlite3VdbeSerialTypeLen(serial_type);
-    assert( len<=nBuf );
-    while( i-- ){
-      buf[i] = (v&0xFF);
-      v >>= 8;
-    }
-    return len;
-  }
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( !(fg&MEM_Zero) );
+  assert( !(fg&(MEM_Str|MEM_Blob)) );
+  assert( fg&(MEM_Int|MEM_Real) );
+  assert( (pMem->flags&MEM_RowSet)==0 );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-  /* String or blob */
-  if( serial_type>=12 ){
-    assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.i:0)
-             == sqlite3VdbeSerialTypeLen(serial_type) );
-    assert( pMem->n<=nBuf );
-    len = pMem->n;
-    memcpy(buf, pMem->z, len);
-    if( pMem->flags & MEM_Zero ){
-      len += pMem->u.i;
-      if( len>nBuf ){
-        len = nBuf;
-      }
-      memset(&buf[pMem->n], 0, len-pMem->n);
-    }
-    return len;
+
+  if( sqlite3VdbeMemGrow(pMem, nByte, 0) ){
+    return SQLITE_NOMEM;
   }
 
-  /* NULL or constants 0 or 1 */
-  return 0;
+  /* For a Real or Integer, use sqlite3_mprintf() to produce the UTF-8
+  ** string representation of the value. Then, if the required encoding
+  ** is UTF-16le or UTF-16be do a translation.
+  ** 
+  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
+  */
+  if( fg & MEM_Int ){
+    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
+  }else{
+    assert( fg & MEM_Real );
+    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
+  }
+  pMem->n = sqlite3Strlen30(pMem->z);
+  pMem->enc = SQLITE_UTF8;
+  pMem->flags |= MEM_Str|MEM_Term;
+  sqlite3VdbeChangeEncoding(pMem, enc);
+  return rc;
 }
 
 /*
-** Deserialize the data blob pointed to by buf as serial type serial_type
-** and store the result in pMem.  Return the number of bytes read.
-*/ 
-SQLITE_PRIVATE int sqlite3VdbeSerialGet(
-  const unsigned char *buf,     /* Buffer to deserialize from */
-  u32 serial_type,              /* Serial type to deserialize */
-  Mem *pMem                     /* Memory cell to write value into */
-){
-  switch( serial_type ){
-    case 10:   /* Reserved for future use */
-    case 11:   /* Reserved for future use */
-    case 0: {  /* NULL */
-      pMem->flags = MEM_Null;
-      break;
-    }
-    case 1: { /* 1-byte signed integer */
-      pMem->u.i = (signed char)buf[0];
-      pMem->flags = MEM_Int;
-      return 1;
-    }
-    case 2: { /* 2-byte signed integer */
-      pMem->u.i = (((signed char)buf[0])<<8) | buf[1];
-      pMem->flags = MEM_Int;
-      return 2;
-    }
-    case 3: { /* 3-byte signed integer */
-      pMem->u.i = (((signed char)buf[0])<<16) | (buf[1]<<8) | buf[2];
-      pMem->flags = MEM_Int;
-      return 3;
-    }
-    case 4: { /* 4-byte signed integer */
-      pMem->u.i = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
-      pMem->flags = MEM_Int;
-      return 4;
-    }
-    case 5: { /* 6-byte signed integer */
-      u64 x = (((signed char)buf[0])<<8) | buf[1];
-      u32 y = (buf[2]<<24) | (buf[3]<<16) | (buf[4]<<8) | buf[5];
-      x = (x<<32) | y;
-      pMem->u.i = *(i64*)&x;
-      pMem->flags = MEM_Int;
-      return 6;
-    }
-    case 6:   /* 8-byte signed integer */
-    case 7: { /* IEEE floating point */
-      u64 x;
-      u32 y;
-#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
-      /* Verify that integers and floating point values use the same
-      ** byte order.  Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
-      ** defined that 64-bit floating point values really are mixed
-      ** endian.
-      */
-      static const u64 t1 = ((u64)0x3ff00000)<<32;
-      static const double r1 = 1.0;
-      u64 t2 = t1;
-      swapMixedEndianFloat(t2);
-      assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
-#endif
+** Memory cell pMem contains the context of an aggregate function.
+** This routine calls the finalize method for that function.  The
+** result of the aggregate is stored back into pMem.
+**
+** Return SQLITE_ERROR if the finalizer reports an error.  SQLITE_OK
+** otherwise.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){
+  int rc = SQLITE_OK;
+  if( ALWAYS(pFunc && pFunc->xFinalize) ){
+    sqlite3_context ctx;
+    assert( (pMem->flags & MEM_Null)!=0 || pFunc==pMem->u.pDef );
+    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+    memset(&ctx, 0, sizeof(ctx));
+    ctx.s.flags = MEM_Null;
+    ctx.s.db = pMem->db;
+    ctx.pMem = pMem;
+    ctx.pFunc = pFunc;
+    pFunc->xFinalize(&ctx);
+    assert( 0==(pMem->flags&MEM_Dyn) && !pMem->xDel );
+    sqlite3DbFree(pMem->db, pMem->zMalloc);
+    memcpy(pMem, &ctx.s, sizeof(ctx.s));
+    rc = ctx.isError;
+  }
+  return rc;
+}
 
-      x = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
-      y = (buf[4]<<24) | (buf[5]<<16) | (buf[6]<<8) | buf[7];
-      x = (x<<32) | y;
-      if( serial_type==6 ){
-        pMem->u.i = *(i64*)&x;
-        pMem->flags = MEM_Int;
-      }else{
-        assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
-        swapMixedEndianFloat(x);
-        memcpy(&pMem->r, &x, sizeof(x));
-        pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
-      }
-      return 8;
-    }
-    case 8:    /* Integer 0 */
-    case 9: {  /* Integer 1 */
-      pMem->u.i = serial_type-8;
-      pMem->flags = MEM_Int;
-      return 0;
-    }
-    default: {
-      int len = (serial_type-12)/2;
-      pMem->z = (char *)buf;
-      pMem->n = len;
-      pMem->xDel = 0;
-      if( serial_type&0x01 ){
-        pMem->flags = MEM_Str | MEM_Ephem;
-      }else{
-        pMem->flags = MEM_Blob | MEM_Ephem;
-      }
-      return len;
+/*
+** If the memory cell contains a string value that must be freed by
+** invoking an external callback, free it now. Calling this function
+** does not free any Mem.zMalloc buffer.
+*/
+SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p){
+  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
+  testcase( p->flags & MEM_Agg );
+  testcase( p->flags & MEM_Dyn );
+  testcase( p->flags & MEM_RowSet );
+  testcase( p->flags & MEM_Frame );
+  if( p->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame) ){
+    if( p->flags&MEM_Agg ){
+      sqlite3VdbeMemFinalize(p, p->u.pDef);
+      assert( (p->flags & MEM_Agg)==0 );
+      sqlite3VdbeMemRelease(p);
+    }else if( p->flags&MEM_Dyn && p->xDel ){
+      assert( (p->flags&MEM_RowSet)==0 );
+      p->xDel((void *)p->z);
+      p->xDel = 0;
+    }else if( p->flags&MEM_RowSet ){
+      sqlite3RowSetClear(p->u.pRowSet);
+    }else if( p->flags&MEM_Frame ){
+      sqlite3VdbeMemSetNull(p);
     }
   }
-  return 0;
 }
 
+/*
+** Release any memory held by the Mem. This may leave the Mem in an
+** inconsistent state, for example with (Mem.z==0) and
+** (Mem.type==SQLITE_TEXT).
+*/
+SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p){
+  sqlite3VdbeMemReleaseExternal(p);
+  sqlite3DbFree(p->db, p->zMalloc);
+  p->z = 0;
+  p->zMalloc = 0;
+  p->xDel = 0;
+}
 
 /*
-** Given the nKey-byte encoding of a record in pKey[], parse the
-** record into a UnpackedRecord structure.  Return a pointer to
-** that structure.
-**
-** The calling function might provide szSpace bytes of memory
-** space at pSpace.  This space can be used to hold the returned
-** VDbeParsedRecord structure if it is large enough.  If it is
-** not big enough, space is obtained from sqlite3_malloc().
+** Convert a 64-bit IEEE double into a 64-bit signed integer.
+** If the double is too large, return 0x8000000000000000.
 **
-** The returned structure should be closed by a call to
-** sqlite3VdbeDeleteUnpackedRecord().
-*/ 
-SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(
-  KeyInfo *pKeyInfo,     /* Information about the record format */
-  int nKey,              /* Size of the binary record */
-  const void *pKey,      /* The binary record */
-  void *pSpace,          /* Space available to hold resulting object */
-  int szSpace            /* Size of pSpace[] in bytes */
-){
-  const unsigned char *aKey = (const unsigned char *)pKey;
-  UnpackedRecord *p;
-  int nByte;
-  int i, idx, d;
-  u32 szHdr;
-  Mem *pMem;
-  
-  assert( sizeof(Mem)>sizeof(*p) );
-  nByte = sizeof(Mem)*(pKeyInfo->nField+2);
-  if( nByte>szSpace ){
-    p = sqlite3DbMallocRaw(pKeyInfo->db, nByte);
-    if( p==0 ) return 0;
-    p->needFree = 1;
+** Most systems appear to do this simply by assigning
+** variables and without the extra range tests.  But
+** there are reports that windows throws an expection
+** if the floating point value is out of range. (See ticket #2880.)
+** Because we do not completely understand the problem, we will
+** take the conservative approach and always do range tests
+** before attempting the conversion.
+*/
+static i64 doubleToInt64(double r){
+  /*
+  ** Many compilers we encounter do not define constants for the
+  ** minimum and maximum 64-bit integers, or they define them
+  ** inconsistently.  And many do not understand the "LL" notation.
+  ** So we define our own static constants here using nothing
+  ** larger than a 32-bit integer constant.
+  */
+  static const i64 maxInt = LARGEST_INT64;
+  static const i64 minInt = SMALLEST_INT64;
+
+  if( r<(double)minInt ){
+    return minInt;
+  }else if( r>(double)maxInt ){
+    /* minInt is correct here - not maxInt.  It turns out that assigning
+    ** a very large positive number to an integer results in a very large
+    ** negative integer.  This makes no sense, but it is what x86 hardware
+    ** does so for compatibility we will do the same in software. */
+    return minInt;
   }else{
-    p = pSpace;
-    p->needFree = 0;
+    return (i64)r;
   }
-  p->pKeyInfo = pKeyInfo;
-  p->nField = pKeyInfo->nField + 1;
-  p->needDestroy = 1;
-  p->aMem = pMem = &((Mem*)p)[1];
-  idx = getVarint32(aKey, szHdr);
-  d = szHdr;
-  i = 0;
-  while( idx<szHdr && i<p->nField ){
-    u32 serial_type;
+}
 
-    idx += getVarint32( aKey+idx, serial_type);
-    if( d>=nKey && sqlite3VdbeSerialTypeLen(serial_type)>0 ) break;
-    pMem->enc = pKeyInfo->enc;
-    pMem->db = pKeyInfo->db;
-    pMem->flags = 0;
-    pMem->zMalloc = 0;
-    d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
-    pMem++;
-    i++;
+/*
+** Return some kind of integer value which is the best we can do
+** at representing the value that *pMem describes as an integer.
+** If pMem is an integer, then the value is exact.  If pMem is
+** a floating-point then the value returned is the integer part.
+** If pMem is a string or blob, then we make an attempt to convert
+** it into a integer and return that.  If pMem represents an
+** an SQL-NULL value, return 0.
+**
+** If pMem represents a string value, its encoding might be changed.
+*/
+SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem *pMem){
+  int flags;
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
+  flags = pMem->flags;
+  if( flags & MEM_Int ){
+    return pMem->u.i;
+  }else if( flags & MEM_Real ){
+    return doubleToInt64(pMem->r);
+  }else if( flags & (MEM_Str|MEM_Blob) ){
+    i64 value;
+    pMem->flags |= MEM_Str;
+    if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8)
+       || sqlite3VdbeMemNulTerminate(pMem) ){
+      return 0;
+    }
+    assert( pMem->z );
+    sqlite3Atoi64(pMem->z, &value);
+    return value;
+  }else{
+    return 0;
   }
-  p->nField = i;
-  return (void*)p;
 }
 
 /*
-** This routine destroys a UnpackedRecord object
+** Return the best representation of pMem that we can get into a
+** double.  If pMem is already a double or an integer, return its
+** value.  If it is a string or blob, try to convert it to a double.
+** If it is a NULL, return 0.0.
 */
-SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord *p){
-  if( p ){
-    if( p->needDestroy ){
-      int i;
-      Mem *pMem;
-      for(i=0, pMem=p->aMem; i<p->nField; i++, pMem++){
-        if( pMem->zMalloc ){
-          sqlite3VdbeMemRelease(pMem);
-        }
-      }
-    }
-    if( p->needFree ){
-      sqlite3_free(p);
+SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem *pMem){
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
+  if( pMem->flags & MEM_Real ){
+    return pMem->r;
+  }else if( pMem->flags & MEM_Int ){
+    return (double)pMem->u.i;
+  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
+    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+    double val = (double)0;
+    pMem->flags |= MEM_Str;
+    if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8)
+       || sqlite3VdbeMemNulTerminate(pMem) ){
+      /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+      return (double)0;
     }
+    assert( pMem->z );
+    sqlite3AtoF(pMem->z, &val);
+    return val;
+  }else{
+    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+    return (double)0;
   }
 }
 
 /*
-** This function compares the two table rows or index records
-** specified by {nKey1, pKey1} and pPKey2.  It returns a negative, zero
-** or positive integer if {nKey1, pKey1} is less than, equal to or 
-** greater than pPKey2.  The {nKey1, pKey1} key must be a blob
-** created by th OP_MakeRecord opcode of the VDBE.  The pPKey2
-** key must be a parsed key such as obtained from
-** sqlite3VdbeParseRecord.
-**
-** Key1 and Key2 do not have to contain the same number of fields.
-** But if the lengths differ, Key2 must be the shorter of the two.
-**
-** Historical note: In earlier versions of this routine both Key1
-** and Key2 were blobs obtained from OP_MakeRecord.  But we found
-** that in typical use the same Key2 would be submitted multiple times
-** in a row.  So an optimization was added to parse the Key2 key
-** separately and submit the parsed version.  In this way, we avoid
-** parsing the same Key2 multiple times in a row.
+** The MEM structure is already a MEM_Real.  Try to also make it a
+** MEM_Int if we can.
 */
-SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
-  int nKey1, const void *pKey1, 
-  UnpackedRecord *pPKey2
-){
-  u32 d1;            /* Offset into aKey[] of next data element */
-  u32 idx1;          /* Offset into aKey[] of next header element */
-  u32 szHdr1;        /* Number of bytes in header */
-  int i = 0;
-  int nField;
-  int rc = 0;
-  const unsigned char *aKey1 = (const unsigned char *)pKey1;
-  KeyInfo *pKeyInfo;
-  Mem mem1;
-
-  pKeyInfo = pPKey2->pKeyInfo;
-  mem1.enc = pKeyInfo->enc;
-  mem1.db = pKeyInfo->db;
-  mem1.flags = 0;
-  mem1.zMalloc = 0;
-  
-  idx1 = getVarint32(aKey1, szHdr1);
-  d1 = szHdr1;
-  nField = pKeyInfo->nField;
-  while( idx1<szHdr1 && i<pPKey2->nField ){
-    u32 serial_type1;
-
-    /* Read the serial types for the next element in each key. */
-    idx1 += getVarint32( aKey1+idx1, serial_type1 );
-    if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
-
-    /* Extract the values to be compared.
-    */
-    d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
+SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem *pMem){
+  assert( pMem->flags & MEM_Real );
+  assert( (pMem->flags & MEM_RowSet)==0 );
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-    /* Do the comparison
-    */
-    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
-                           i<nField ? pKeyInfo->aColl[i] : 0);
-    if( rc!=0 ){
-      break;
-    }
-    i++;
-  }
-  if( mem1.zMalloc ) sqlite3VdbeMemRelease(&mem1);
+  pMem->u.i = doubleToInt64(pMem->r);
 
-  /* One of the keys ran out of fields, but all the fields up to that point
-  ** were equal. If the incrKey flag is true, then the second key is
-  ** treated as larger.
-  */
-  if( rc==0 ){
-    if( pKeyInfo->incrKey ){
-      rc = -1;
-    }else if( !pKeyInfo->prefixIsEqual ){
-      if( d1<nKey1 ){
-        rc = 1;
-      }
-    }
-  }else if( pKeyInfo->aSortOrder && i<pKeyInfo->nField
-               && pKeyInfo->aSortOrder[i] ){
-    rc = -rc;
+  /* Only mark the value as an integer if
+  **
+  **    (1) the round-trip conversion real->int->real is a no-op, and
+  **    (2) The integer is neither the largest nor the smallest
+  **        possible integer (ticket #3922)
+  **
+  ** The second and third terms in the following conditional enforces
+  ** the second condition under the assumption that addition overflow causes
+  ** values to wrap around.  On x86 hardware, the third term is always
+  ** true and could be omitted.  But we leave it in because other
+  ** architectures might behave differently.
+  */
+  if( pMem->r==(double)pMem->u.i && pMem->u.i>SMALLEST_INT64
+      && ALWAYS(pMem->u.i<LARGEST_INT64) ){
+    pMem->flags |= MEM_Int;
   }
-
-  return rc;
 }
 
 /*
-** The argument is an index entry composed using the OP_MakeRecord opcode.
-** The last entry in this record should be an integer (specifically
-** an integer rowid).  This routine returns the number of bytes in
-** that integer.
+** Convert pMem to type integer.  Invalidate any prior representations.
 */
-SQLITE_PRIVATE int sqlite3VdbeIdxRowidLen(const u8 *aKey){
-  u32 szHdr;        /* Size of the header */
-  u32 typeRowid;    /* Serial type of the rowid */
+SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem *pMem){
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( (pMem->flags & MEM_RowSet)==0 );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-  (void)getVarint32(aKey, szHdr);
-  (void)getVarint32(&aKey[szHdr-1], typeRowid);
-  return sqlite3VdbeSerialTypeLen(typeRowid);
+  pMem->u.i = sqlite3VdbeIntValue(pMem);
+  MemSetTypeFlag(pMem, MEM_Int);
+  return SQLITE_OK;
 }
-  
 
 /*
-** pCur points at an index entry created using the OP_MakeRecord opcode.
-** Read the rowid (the last field in the record) and store it in *rowid.
-** Return SQLITE_OK if everything works, or an error code otherwise.
+** Convert pMem so that it is of type MEM_Real.
+** Invalidate any prior representations.
 */
-SQLITE_PRIVATE int sqlite3VdbeIdxRowid(BtCursor *pCur, i64 *rowid){
-  i64 nCellKey = 0;
-  int rc;
-  u32 szHdr;        /* Size of the header */
-  u32 typeRowid;    /* Serial type of the rowid */
-  u32 lenRowid;     /* Size of the rowid */
-  Mem m, v;
+SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem *pMem){
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-  sqlite3BtreeKeySize(pCur, &nCellKey);
-  if( nCellKey<=0 ){
-    return SQLITE_CORRUPT_BKPT;
-  }
-  m.flags = 0;
-  m.db = 0;
-  m.zMalloc = 0;
-  rc = sqlite3VdbeMemFromBtree(pCur, 0, nCellKey, 1, &m);
-  if( rc ){
-    return rc;
-  }
-  (void)getVarint32((u8*)m.z, szHdr);
-  (void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
-  lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
-  sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
-  *rowid = v.u.i;
-  sqlite3VdbeMemRelease(&m);
+  pMem->r = sqlite3VdbeRealValue(pMem);
+  MemSetTypeFlag(pMem, MEM_Real);
   return SQLITE_OK;
 }
 
 /*
-** Compare the key of the index entry that cursor pC is point to against
-** the key string in pKey (of length nKey).  Write into *pRes a number
-** that is negative, zero, or positive if pC is less than, equal to,
-** or greater than pKey.  Return SQLITE_OK on success.
-**
-** pKey is either created without a rowid or is truncated so that it
-** omits the rowid at the end.  The rowid at the end of the index entry
-** is ignored as well.
+** Convert pMem so that it has types MEM_Real or MEM_Int or both.
+** Invalidate any prior representations.
 */
-SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(
-  Cursor *pC,                 /* The cursor to compare against */
-  UnpackedRecord *pUnpacked,
-  int nKey, const u8 *pKey,   /* The key to compare */
-  int *res                    /* Write the comparison result here */
-){
-  i64 nCellKey = 0;
-  int rc;
-  BtCursor *pCur = pC->pCursor;
-  int lenRowid;
-  Mem m;
-  UnpackedRecord *pRec;
-  char zSpace[200];
-
-  sqlite3BtreeKeySize(pCur, &nCellKey);
-  if( nCellKey<=0 ){
-    *res = 0;
-    return SQLITE_OK;
-  }
-  m.db = 0;
-  m.flags = 0;
-  m.zMalloc = 0;
-  rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, nCellKey, 1, &m);
-  if( rc ){
-    return rc;
-  }
-  lenRowid = sqlite3VdbeIdxRowidLen((u8*)m.z);
-  if( !pUnpacked ){
-    pRec = sqlite3VdbeRecordUnpack(pC->pKeyInfo, nKey, pKey,
-                                zSpace, sizeof(zSpace));
+SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem *pMem){
+  double r1, r2;
+  i64 i;
+  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 );
+  assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  r1 = sqlite3VdbeRealValue(pMem);
+  i = doubleToInt64(r1);
+  r2 = (double)i;
+  if( r1==r2 ){
+    sqlite3VdbeMemIntegerify(pMem);
   }else{
-    pRec = pUnpacked;
-  }
-  if( pRec==0 ){
-    return SQLITE_NOMEM;
-  }
-  *res = sqlite3VdbeRecordCompare(m.n-lenRowid, m.z, pRec);
-  if( !pUnpacked ){
-    sqlite3VdbeDeleteUnpackedRecord(pRec);
+    pMem->r = r1;
+    MemSetTypeFlag(pMem, MEM_Real);
   }
-  sqlite3VdbeMemRelease(&m);
   return SQLITE_OK;
 }
 
 /*
-** This routine sets the value to be returned by subsequent calls to
-** sqlite3_changes() on the database handle 'db'. 
+** Delete any previous value and set the value stored in *pMem to NULL.
 */
-SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
-  assert( sqlite3_mutex_held(db->mutex) );
-  db->nChange = nChange;
-  db->nTotalChange += nChange;
+SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem *pMem){
+  if( pMem->flags & MEM_Frame ){
+    sqlite3VdbeFrameDelete(pMem->u.pFrame);
+  }
+  if( pMem->flags & MEM_RowSet ){
+    sqlite3RowSetClear(pMem->u.pRowSet);
+  }
+  MemSetTypeFlag(pMem, MEM_Null);
+  pMem->type = SQLITE_NULL;
 }
 
 /*
-** Set a flag in the vdbe to update the change counter when it is finalised
-** or reset.
+** Delete any previous value and set the value to be a BLOB of length
+** n containing all zeros.
 */
-SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe *v){
-  v->changeCntOn = 1;
-}
+SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem *pMem, int n){
+  sqlite3VdbeMemRelease(pMem);
+  pMem->flags = MEM_Blob|MEM_Zero;
+  pMem->type = SQLITE_BLOB;
+  pMem->n = 0;
+  if( n<0 ) n = 0;
+  pMem->u.nZero = n;
+  pMem->enc = SQLITE_UTF8;
 
-/*
-** Mark every prepared statement associated with a database connection
-** as expired.
-**
-** An expired statement means that recompilation of the statement is
-** recommend.  Statements expire when things happen that make their
-** programs obsolete.  Removing user-defined functions or collating
-** sequences, or changing an authorization function are the types of
-** things that make prepared statements obsolete.
-*/
-SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3 *db){
-  Vdbe *p;
-  for(p = db->pVdbe; p; p=p->pNext){
-    p->expired = 1;
+#ifdef SQLITE_OMIT_INCRBLOB
+  sqlite3VdbeMemGrow(pMem, n, 0);
+  if( pMem->z ){
+    pMem->n = n;
+    memset(pMem->z, 0, n);
   }
+#endif
 }
 
 /*
-** Return the database associated with the Vdbe.
+** Delete any previous value and set the value stored in *pMem to val,
+** manifest type INTEGER.
 */
-SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe *v){
-  return v->db;
+SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){
+  sqlite3VdbeMemRelease(pMem);
+  pMem->u.i = val;
+  pMem->flags = MEM_Int;
+  pMem->type = SQLITE_INTEGER;
 }
 
-/************** End of vdbeaux.c *********************************************/
-/************** Begin file vdbeapi.c *****************************************/
-/*
-** 2004 May 26
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-**
-** This file contains code use to implement APIs that are part of the
-** VDBE.
-*/
-
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-/*
-** The following structure contains pointers to the end points of a
-** doubly-linked list of all compiled SQL statements that may be holding
-** buffers eligible for release when the sqlite3_release_memory() interface is
-** invoked. Access to this list is protected by the SQLITE_MUTEX_STATIC_LRU2
-** mutex.
-**
-** Statements are added to the end of this list when sqlite3_reset() is
-** called. They are removed either when sqlite3_step() or sqlite3_finalize()
-** is called. When statements are added to this list, the associated 
-** register array (p->aMem[1..p->nMem]) may contain dynamic buffers that
-** can be freed using sqlite3VdbeReleaseMemory().
-**
-** When statements are added or removed from this list, the mutex
-** associated with the Vdbe being added or removed (Vdbe.db->mutex) is
-** already held. The LRU2 mutex is then obtained, blocking if necessary,
-** the linked-list pointers manipulated and the LRU2 mutex relinquished.
-*/
-struct StatementLruList {
-  Vdbe *pFirst;
-  Vdbe *pLast;
-};
-static struct StatementLruList sqlite3LruStatements;
-
 /*
-** Check that the list looks to be internally consistent. This is used
-** as part of an assert() statement as follows:
-**
-**   assert( stmtLruCheck() );
+** Delete any previous value and set the value stored in *pMem to val,
+** manifest type REAL.
 */
-#ifndef NDEBUG
-static int stmtLruCheck(){
-  Vdbe *p;
-  for(p=sqlite3LruStatements.pFirst; p; p=p->pLruNext){
-    assert(p->pLruNext || p==sqlite3LruStatements.pLast);
-    assert(!p->pLruNext || p->pLruNext->pLruPrev==p);
-    assert(p->pLruPrev || p==sqlite3LruStatements.pFirst);
-    assert(!p->pLruPrev || p->pLruPrev->pLruNext==p);
+SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
+  if( sqlite3IsNaN(val) ){
+    sqlite3VdbeMemSetNull(pMem);
+  }else{
+    sqlite3VdbeMemRelease(pMem);
+    pMem->r = val;
+    pMem->flags = MEM_Real;
+    pMem->type = SQLITE_FLOAT;
   }
-  return 1;
 }
-#endif
 
 /*
-** Add vdbe p to the end of the statement lru list. It is assumed that
-** p is not already part of the list when this is called. The lru list
-** is protected by the SQLITE_MUTEX_STATIC_LRU mutex.
+** Delete any previous value and set the value of pMem to be an
+** empty boolean index.
 */
-static void stmtLruAdd(Vdbe *p){
-  sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-
-  if( p->pLruPrev || p->pLruNext || sqlite3LruStatements.pFirst==p ){
-    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-    return;
-  }
-
-  assert( stmtLruCheck() );
-
-  if( !sqlite3LruStatements.pFirst ){
-    assert( !sqlite3LruStatements.pLast );
-    sqlite3LruStatements.pFirst = p;
-    sqlite3LruStatements.pLast = p;
+SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem *pMem){
+  sqlite3 *db = pMem->db;
+  assert( db!=0 );
+  assert( (pMem->flags & MEM_RowSet)==0 );
+  sqlite3VdbeMemRelease(pMem);
+  pMem->zMalloc = sqlite3DbMallocRaw(db, 64);
+  if( db->mallocFailed ){
+    pMem->flags = MEM_Null;
   }else{
-    assert( !sqlite3LruStatements.pLast->pLruNext );
-    p->pLruPrev = sqlite3LruStatements.pLast;
-    sqlite3LruStatements.pLast->pLruNext = p;
-    sqlite3LruStatements.pLast = p;
+    assert( pMem->zMalloc );
+    pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, 
+                                       sqlite3DbMallocSize(db, pMem->zMalloc));
+    assert( pMem->u.pRowSet!=0 );
+    pMem->flags = MEM_RowSet;
   }
-
-  assert( stmtLruCheck() );
-
-  sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
 }
 
 /*
-** Assuming the SQLITE_MUTEX_STATIC_LRU2 mutext is already held, remove
-** statement p from the least-recently-used statement list. If the 
-** statement is not currently part of the list, this call is a no-op.
+** Return true if the Mem object contains a TEXT or BLOB that is
+** too large - whose size exceeds SQLITE_MAX_LENGTH.
 */
-static void stmtLruRemoveNomutex(Vdbe *p){
-  if( p->pLruPrev || p->pLruNext || p==sqlite3LruStatements.pFirst ){
-    assert( stmtLruCheck() );
-    if( p->pLruNext ){
-      p->pLruNext->pLruPrev = p->pLruPrev;
-    }else{
-      sqlite3LruStatements.pLast = p->pLruPrev;
-    }
-    if( p->pLruPrev ){
-      p->pLruPrev->pLruNext = p->pLruNext;
-    }else{
-      sqlite3LruStatements.pFirst = p->pLruNext;
+SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem *p){
+  assert( p->db!=0 );
+  if( p->flags & (MEM_Str|MEM_Blob) ){
+    int n = p->n;
+    if( p->flags & MEM_Zero ){
+      n += p->u.nZero;
     }
-    p->pLruNext = 0;
-    p->pLruPrev = 0;
-    assert( stmtLruCheck() );
+    return n>p->db->aLimit[SQLITE_LIMIT_LENGTH];
   }
+  return 0; 
 }
 
 /*
-** Assuming the SQLITE_MUTEX_STATIC_LRU2 mutext is not held, remove
-** statement p from the least-recently-used statement list. If the 
-** statement is not currently part of the list, this call is a no-op.
+** Size of struct Mem not including the Mem.zMalloc member.
 */
-static void stmtLruRemove(Vdbe *p){
-  sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-  stmtLruRemoveNomutex(p);
-  sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-}
+#define MEMCELLSIZE (size_t)(&(((Mem *)0)->zMalloc))
 
 /*
-** Try to release n bytes of memory by freeing buffers associated 
-** with the memory registers of currently unused vdbes.
+** Make an shallow copy of pFrom into pTo.  Prior contents of
+** pTo are freed.  The pFrom->z field is not duplicated.  If
+** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
+** and flags gets srcType (either MEM_Ephem or MEM_Static).
 */
-SQLITE_PRIVATE int sqlite3VdbeReleaseMemory(int n){
-  Vdbe *p;
-  Vdbe *pNext;
-  int nFree = 0;
-
-  sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-  for(p=sqlite3LruStatements.pFirst; p && nFree<n; p=pNext){
-    pNext = p->pLruNext;
-
-    /* For each statement handle in the lru list, attempt to obtain the
-    ** associated database mutex. If it cannot be obtained, continue
-    ** to the next statement handle. It is not possible to block on
-    ** the database mutex - that could cause deadlock.
-    */
-    if( SQLITE_OK==sqlite3_mutex_try(p->db->mutex) ){
-      nFree += sqlite3VdbeReleaseBuffers(p);
-      stmtLruRemoveNomutex(p);
-      sqlite3_mutex_leave(p->db->mutex);
-    }
-  }
-  sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU2));
-
-  return nFree;
-}
-
-/*
-** Call sqlite3Reprepare() on the statement. Remove it from the
-** lru list before doing so, as Reprepare() will free all the
-** memory register buffers anyway.
-*/
-int vdbeReprepare(Vdbe *p){
-  stmtLruRemove(p);
-  return sqlite3Reprepare(p);
+SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
+  assert( (pFrom->flags & MEM_RowSet)==0 );
+  sqlite3VdbeMemReleaseExternal(pTo);
+  memcpy(pTo, pFrom, MEMCELLSIZE);
+  pTo->xDel = 0;
+  if( (pFrom->flags&MEM_Dyn)!=0 || pFrom->z==pFrom->zMalloc ){
+    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
+    assert( srcType==MEM_Ephem || srcType==MEM_Static );
+    pTo->flags |= srcType;
+  }
 }
 
-#else       /* !SQLITE_ENABLE_MEMORY_MANAGEMENT */
-  #define stmtLruRemove(x)
-  #define stmtLruAdd(x)
-  #define vdbeReprepare(x) sqlite3Reprepare(x)
-#endif
-
-
 /*
-** Return TRUE (non-zero) of the statement supplied as an argument needs
-** to be recompiled.  A statement needs to be recompiled whenever the
-** execution environment changes in a way that would alter the program
-** that sqlite3_prepare() generates.  For example, if new functions or
-** collating sequences are registered or if an authorizer function is
-** added or changed.
+** Make a full copy of pFrom into pTo.  Prior contents of pTo are
+** freed before the copy is made.
 */
-SQLITE_API int sqlite3_expired(sqlite3_stmt *pStmt){
-  Vdbe *p = (Vdbe*)pStmt;
-  return p==0 || p->expired;
-}
+SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
+  int rc = SQLITE_OK;
 
-/*
-** The following routine destroys a virtual machine that is created by
-** the sqlite3_compile() routine. The integer returned is an SQLITE_
-** success/failure code that describes the result of executing the virtual
-** machine.
-**
-** This routine sets the error code and string returned by
-** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
-*/
-SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt){
-  int rc;
-  if( pStmt==0 ){
-    rc = SQLITE_OK;
-  }else{
-    Vdbe *v = (Vdbe*)pStmt;
-#ifndef SQLITE_MUTEX_NOOP
-    sqlite3_mutex *mutex = v->db->mutex;
-#endif
-    sqlite3_mutex_enter(mutex);
-    stmtLruRemove(v);
-    rc = sqlite3VdbeFinalize(v);
-    sqlite3_mutex_leave(mutex);
+  assert( (pFrom->flags & MEM_RowSet)==0 );
+  sqlite3VdbeMemReleaseExternal(pTo);
+  memcpy(pTo, pFrom, MEMCELLSIZE);
+  pTo->flags &= ~MEM_Dyn;
+
+  if( pTo->flags&(MEM_Str|MEM_Blob) ){
+    if( 0==(pFrom->flags&MEM_Static) ){
+      pTo->flags |= MEM_Ephem;
+      rc = sqlite3VdbeMemMakeWriteable(pTo);
+    }
   }
+
   return rc;
 }
 
 /*
-** Terminate the current execution of an SQL statement and reset it
-** back to its starting state so that it can be reused. A success code from
-** the prior execution is returned.
+** Transfer the contents of pFrom to pTo. Any existing value in pTo is
+** freed. If pFrom contains ephemeral data, a copy is made.
 **
-** This routine sets the error code and string returned by
-** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
+** pFrom contains an SQL NULL when this routine returns.
 */
-SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt){
-  int rc;
-  if( pStmt==0 ){
-    rc = SQLITE_OK;
-  }else{
-    Vdbe *v = (Vdbe*)pStmt;
-    sqlite3_mutex_enter(v->db->mutex);
-    rc = sqlite3VdbeReset(v, 1);
-    stmtLruAdd(v);
-    sqlite3VdbeMakeReady(v, -1, 0, 0, 0);
-    assert( (rc & (v->db->errMask))==rc );
-    sqlite3_mutex_leave(v->db->mutex);
-  }
-  return rc;
+SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem *pTo, Mem *pFrom){
+  assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) );
+  assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) );
+  assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db );
+
+  sqlite3VdbeMemRelease(pTo);
+  memcpy(pTo, pFrom, sizeof(Mem));
+  pFrom->flags = MEM_Null;
+  pFrom->xDel = 0;
+  pFrom->zMalloc = 0;
 }
 
 /*
-** Set all the parameters in the compiled SQL statement to NULL.
+** Change the value of a Mem to be a string or a BLOB.
+**
+** The memory management strategy depends on the value of the xDel
+** parameter. If the value passed is SQLITE_TRANSIENT, then the 
+** string is copied into a (possibly existing) buffer managed by the 
+** Mem structure. Otherwise, any existing buffer is freed and the
+** pointer copied.
+**
+** If the string is too large (if it exceeds the SQLITE_LIMIT_LENGTH
+** size limit) then no memory allocation occurs.  If the string can be
+** stored without allocating memory, then it is.  If a memory allocation
+** is required to store the string, then value of pMem is unchanged.  In
+** either case, SQLITE_TOOBIG is returned.
 */
-SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt *pStmt){
-  int i;
-  int rc = SQLITE_OK;
-  Vdbe *p = (Vdbe*)pStmt;
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = ((Vdbe*)pStmt)->db->mutex;
-#endif
-  sqlite3_mutex_enter(mutex);
-  for(i=0; i<p->nVar; i++){
-    sqlite3VdbeMemRelease(&p->aVar[i]);
-    p->aVar[i].flags = MEM_Null;
+SQLITE_PRIVATE int sqlite3VdbeMemSetStr(
+  Mem *pMem,          /* Memory cell to set to string value */
+  const char *z,      /* String pointer */
+  int n,              /* Bytes in string, or negative */
+  u8 enc,             /* Encoding of z.  0 for BLOBs */
+  void (*xDel)(void*) /* Destructor function */
+){
+  int nByte = n;      /* New value for pMem->n */
+  int iLimit;         /* Maximum allowed string or blob size */
+  u16 flags = 0;      /* New value for pMem->flags */
+
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( (pMem->flags & MEM_RowSet)==0 );
+
+  /* If z is a NULL pointer, set pMem to contain an SQL NULL. */
+  if( !z ){
+    sqlite3VdbeMemSetNull(pMem);
+    return SQLITE_OK;
   }
-  sqlite3_mutex_leave(mutex);
-  return rc;
-}
 
+  if( pMem->db ){
+    iLimit = pMem->db->aLimit[SQLITE_LIMIT_LENGTH];
+  }else{
+    iLimit = SQLITE_MAX_LENGTH;
+  }
+  flags = (enc==0?MEM_Blob:MEM_Str);
+  if( nByte<0 ){
+    assert( enc!=0 );
+    if( enc==SQLITE_UTF8 ){
+      for(nByte=0; nByte<=iLimit && z[nByte]; nByte++){}
+    }else{
+      for(nByte=0; nByte<=iLimit && (z[nByte] | z[nByte+1]); nByte+=2){}
+    }
+    flags |= MEM_Term;
+  }
 
-/**************************** sqlite3_value_  *******************************
-** The following routines extract information from a Mem or sqlite3_value
-** structure.
-*/
-SQLITE_API const void *sqlite3_value_blob(sqlite3_value *pVal){
-  Mem *p = (Mem*)pVal;
-  if( p->flags & (MEM_Blob|MEM_Str) ){
-    sqlite3VdbeMemExpandBlob(p);
-    p->flags &= ~MEM_Str;
-    p->flags |= MEM_Blob;
-    return p->z;
+  /* The following block sets the new values of Mem.z and Mem.xDel. It
+  ** also sets a flag in local variable "flags" to indicate the memory
+  ** management (one of MEM_Dyn or MEM_Static).
+  */
+  if( xDel==SQLITE_TRANSIENT ){
+    int nAlloc = nByte;
+    if( flags&MEM_Term ){
+      nAlloc += (enc==SQLITE_UTF8?1:2);
+    }
+    if( nByte>iLimit ){
+      return SQLITE_TOOBIG;
+    }
+    if( sqlite3VdbeMemGrow(pMem, nAlloc, 0) ){
+      return SQLITE_NOMEM;
+    }
+    memcpy(pMem->z, z, nAlloc);
+  }else if( xDel==SQLITE_DYNAMIC ){
+    sqlite3VdbeMemRelease(pMem);
+    pMem->zMalloc = pMem->z = (char *)z;
+    pMem->xDel = 0;
   }else{
-    return sqlite3_value_text(pVal);
+    sqlite3VdbeMemRelease(pMem);
+    pMem->z = (char *)z;
+    pMem->xDel = xDel;
+    flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
   }
-}
-SQLITE_API int sqlite3_value_bytes(sqlite3_value *pVal){
-  return sqlite3ValueBytes(pVal, SQLITE_UTF8);
-}
-SQLITE_API int sqlite3_value_bytes16(sqlite3_value *pVal){
-  return sqlite3ValueBytes(pVal, SQLITE_UTF16NATIVE);
-}
-SQLITE_API double sqlite3_value_double(sqlite3_value *pVal){
-  return sqlite3VdbeRealValue((Mem*)pVal);
-}
-SQLITE_API int sqlite3_value_int(sqlite3_value *pVal){
-  return sqlite3VdbeIntValue((Mem*)pVal);
-}
-SQLITE_API sqlite_int64 sqlite3_value_int64(sqlite3_value *pVal){
-  return sqlite3VdbeIntValue((Mem*)pVal);
-}
-SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value *pVal){
-  return (const unsigned char *)sqlite3ValueText(pVal, SQLITE_UTF8);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_value_text16(sqlite3_value* pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16NATIVE);
-}
-SQLITE_API const void *sqlite3_value_text16be(sqlite3_value *pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16BE);
-}
-SQLITE_API const void *sqlite3_value_text16le(sqlite3_value *pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16LE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-SQLITE_API int sqlite3_value_type(sqlite3_value* pVal){
-  return pVal->type;
-}
 
-/**************************** sqlite3_result_  *******************************
-** The following routines are used by user-defined functions to specify
-** the function result.
-*/
-SQLITE_API void sqlite3_result_blob(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( n>=0 );
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, 0, xDel);
-}
-SQLITE_API void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetDouble(&pCtx->s, rVal);
-}
-SQLITE_API void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pCtx->isError = SQLITE_ERROR;
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, SQLITE_TRANSIENT);
-}
+  pMem->n = nByte;
+  pMem->flags = flags;
+  pMem->enc = (enc==0 ? SQLITE_UTF8 : enc);
+  pMem->type = (enc==0 ? SQLITE_BLOB : SQLITE_TEXT);
+
 #ifndef SQLITE_OMIT_UTF16
-SQLITE_API void sqlite3_result_error16(sqlite3_context *pCtx, const void *z, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pCtx->isError = SQLITE_ERROR;
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16NATIVE, SQLITE_TRANSIENT);
-}
+  if( pMem->enc!=SQLITE_UTF8 && sqlite3VdbeMemHandleBom(pMem) ){
+    return SQLITE_NOMEM;
+  }
 #endif
-SQLITE_API void sqlite3_result_int(sqlite3_context *pCtx, int iVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetInt64(&pCtx->s, (i64)iVal);
-}
-SQLITE_API void sqlite3_result_int64(sqlite3_context *pCtx, i64 iVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetInt64(&pCtx->s, iVal);
-}
-SQLITE_API void sqlite3_result_null(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetNull(&pCtx->s);
-}
-SQLITE_API void sqlite3_result_text(
-  sqlite3_context *pCtx, 
-  const char *z, 
-  int n,
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, xDel);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API void sqlite3_result_text16(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16NATIVE, xDel);
-}
-SQLITE_API void sqlite3_result_text16be(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16BE, xDel);
-}
-SQLITE_API void sqlite3_result_text16le(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16LE, xDel);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-SQLITE_API void sqlite3_result_value(sqlite3_context *pCtx, sqlite3_value *pValue){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemCopy(&pCtx->s, pValue);
-}
-SQLITE_API void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetZeroBlob(&pCtx->s, n);
-}
-SQLITE_API void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
-  pCtx->isError = errCode;
-}
 
-/* Force an SQLITE_TOOBIG error. */
-SQLITE_API void sqlite3_result_error_toobig(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pCtx->isError = SQLITE_TOOBIG;
-  sqlite3VdbeMemSetStr(&pCtx->s, "string or blob too big", -1, 
-                       SQLITE_UTF8, SQLITE_STATIC);
-}
+  if( nByte>iLimit ){
+    return SQLITE_TOOBIG;
+  }
 
-/* An SQLITE_NOMEM error. */
-SQLITE_API void sqlite3_result_error_nomem(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetNull(&pCtx->s);
-  pCtx->isError = SQLITE_NOMEM;
-  pCtx->s.db->mallocFailed = 1;
+  return SQLITE_OK;
 }
 
 /*
-** Execute the statement pStmt, either until a row of data is ready, the
-** statement is completely executed or an error occurs.
+** Compare the values contained by the two memory cells, returning
+** negative, zero or positive if pMem1 is less than, equal to, or greater
+** than pMem2. Sorting order is NULL's first, followed by numbers (integers
+** and reals) sorted numerically, followed by text ordered by the collating
+** sequence pColl and finally blob's ordered by memcmp().
 **
-** This routine implements the bulk of the logic behind the sqlite_step()
-** API.  The only thing omitted is the automatic recompile if a 
-** schema change has occurred.  That detail is handled by the
-** outer sqlite3_step() wrapper procedure.
+** Two NULL values are considered equal by this function.
 */
-static int sqlite3Step(Vdbe *p){
-  sqlite3 *db;
+SQLITE_PRIVATE int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
   int rc;
+  int f1, f2;
+  int combined_flags;
 
-  assert(p);
-  if( p->magic!=VDBE_MAGIC_RUN ){
-    return SQLITE_MISUSE;
+  /* Interchange pMem1 and pMem2 if the collating sequence specifies
+  ** DESC order.
+  */
+  f1 = pMem1->flags;
+  f2 = pMem2->flags;
+  combined_flags = f1|f2;
+  assert( (combined_flags & MEM_RowSet)==0 );
+ 
+  /* If one value is NULL, it is less than the other. If both values
+  ** are NULL, return 0.
+  */
+  if( combined_flags&MEM_Null ){
+    return (f2&MEM_Null) - (f1&MEM_Null);
   }
 
-  /* Assert that malloc() has not failed */
-  db = p->db;
-  assert( !db->mallocFailed );
-
-  if( p->aborted ){
-    return SQLITE_ABORT;
-  }
-  if( p->pc<=0 && p->expired ){
-    if( p->rc==SQLITE_OK ){
-      p->rc = SQLITE_SCHEMA;
+  /* If one value is a number and the other is not, the number is less.
+  ** If both are numbers, compare as reals if one is a real, or as integers
+  ** if both values are integers.
+  */
+  if( combined_flags&(MEM_Int|MEM_Real) ){
+    if( !(f1&(MEM_Int|MEM_Real)) ){
+      return 1;
     }
-    rc = SQLITE_ERROR;
-    goto end_of_step;
-  }
-  if( sqlite3SafetyOn(db) ){
-    p->rc = SQLITE_MISUSE;
-    return SQLITE_MISUSE;
-  }
-  if( p->pc<0 ){
-    /* If there are no other statements currently running, then
-    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
-    ** from interrupting a statement that has not yet started.
-    */
-    if( db->activeVdbeCnt==0 ){
-      db->u1.isInterrupted = 0;
+    if( !(f2&(MEM_Int|MEM_Real)) ){
+      return -1;
     }
-
-#ifndef SQLITE_OMIT_TRACE
-    if( db->xProfile && !db->init.busy ){
-      double rNow;
-      sqlite3OsCurrentTime(db->pVfs, &rNow);
-      p->startTime = (rNow - (int)rNow)*3600.0*24.0*1000000000.0;
+    if( (f1 & f2 & MEM_Int)==0 ){
+      double r1, r2;
+      if( (f1&MEM_Real)==0 ){
+        r1 = (double)pMem1->u.i;
+      }else{
+        r1 = pMem1->r;
+      }
+      if( (f2&MEM_Real)==0 ){
+        r2 = (double)pMem2->u.i;
+      }else{
+        r2 = pMem2->r;
+      }
+      if( r1<r2 ) return -1;
+      if( r1>r2 ) return 1;
+      return 0;
+    }else{
+      assert( f1&MEM_Int );
+      assert( f2&MEM_Int );
+      if( pMem1->u.i < pMem2->u.i ) return -1;
+      if( pMem1->u.i > pMem2->u.i ) return 1;
+      return 0;
     }
-#endif
-
-    db->activeVdbeCnt++;
-    p->pc = 0;
-    stmtLruRemove(p);
-  }
-#ifndef SQLITE_OMIT_EXPLAIN
-  if( p->explain ){
-    rc = sqlite3VdbeList(p);
-  }else
-#endif /* SQLITE_OMIT_EXPLAIN */
-  {
-    rc = sqlite3VdbeExec(p);
-  }
-
-  if( sqlite3SafetyOff(db) ){
-    rc = SQLITE_MISUSE;
   }
 
-#ifndef SQLITE_OMIT_TRACE
-  /* Invoke the profile callback if there is one
+  /* If one value is a string and the other is a blob, the string is less.
+  ** If both are strings, compare using the collating functions.
   */
-  if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy && p->nOp>0
-           && p->aOp[0].opcode==OP_Trace && p->aOp[0].p4.z!=0 ){
-    double rNow;
-    u64 elapseTime;
+  if( combined_flags&MEM_Str ){
+    if( (f1 & MEM_Str)==0 ){
+      return 1;
+    }
+    if( (f2 & MEM_Str)==0 ){
+      return -1;
+    }
 
-    sqlite3OsCurrentTime(db->pVfs, &rNow);
-    elapseTime = (rNow - (int)rNow)*3600.0*24.0*1000000000.0 - p->startTime;
-    db->xProfile(db->pProfileArg, p->aOp[0].p4.z, elapseTime);
-  }
-#endif
+    assert( pMem1->enc==pMem2->enc );
+    assert( pMem1->enc==SQLITE_UTF8 || 
+            pMem1->enc==SQLITE_UTF16LE || pMem1->enc==SQLITE_UTF16BE );
 
-  sqlite3Error(p->db, rc, 0);
-  p->rc = sqlite3ApiExit(p->db, p->rc);
-end_of_step:
-  assert( (rc&0xff)==rc );
-  if( p->zSql && (rc&0xff)<SQLITE_ROW ){
-    /* This behavior occurs if sqlite3_prepare_v2() was used to build
-    ** the prepared statement.  Return error codes directly */
-    sqlite3Error(p->db, p->rc, 0);
-    return p->rc;
-  }else{
-    /* This is for legacy sqlite3_prepare() builds and when the code
-    ** is SQLITE_ROW or SQLITE_DONE */
-    return rc;
-  }
-}
+    /* The collation sequence must be defined at this point, even if
+    ** the user deletes the collation sequence after the vdbe program is
+    ** compiled (this was not always the case).
+    */
+    assert( !pColl || pColl->xCmp );
 
-/*
-** This is the top-level implementation of sqlite3_step().  Call
-** sqlite3Step() to do most of the work.  If a schema error occurs,
-** call sqlite3Reprepare() and try again.
-*/
-#ifdef SQLITE_OMIT_PARSER
-SQLITE_API int sqlite3_step(sqlite3_stmt *pStmt){
-  int rc = SQLITE_MISUSE;
-  if( pStmt ){
-    Vdbe *v;
-    v = (Vdbe*)pStmt;
-    sqlite3_mutex_enter(v->db->mutex);
-    rc = sqlite3Step(v);
-    sqlite3_mutex_leave(v->db->mutex);
-  }
-  return rc;
-}
-#else
-SQLITE_API int sqlite3_step(sqlite3_stmt *pStmt){
-  int rc = SQLITE_MISUSE;
-  if( pStmt ){
-    int cnt = 0;
-    Vdbe *v = (Vdbe*)pStmt;
-    sqlite3 *db = v->db;
-    sqlite3_mutex_enter(db->mutex);
-    while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
-           && cnt++ < 5
-           && vdbeReprepare(v) ){
-      sqlite3_reset(pStmt);
-      v->expired = 0;
-    }
-    if( rc==SQLITE_SCHEMA && v->zSql && db->pErr ){
-      /* This case occurs after failing to recompile an sql statement. 
-      ** The error message from the SQL compiler has already been loaded 
-      ** into the database handle. This block copies the error message 
-      ** from the database handle into the statement and sets the statement
-      ** program counter to 0 to ensure that when the statement is 
-      ** finalized or reset the parser error message is available via
-      ** sqlite3_errmsg() and sqlite3_errcode().
-      */
-      const char *zErr = (const char *)sqlite3_value_text(db->pErr); 
-      sqlite3_free(v->zErrMsg);
-      if( !db->mallocFailed ){
-        v->zErrMsg = sqlite3DbStrDup(db, zErr);
-      } else {
-        v->zErrMsg = 0;
-        v->rc = SQLITE_NOMEM;
+    if( pColl ){
+      if( pMem1->enc==pColl->enc ){
+        /* The strings are already in the correct encoding.  Call the
+        ** comparison function directly */
+        return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z);
+      }else{
+        const void *v1, *v2;
+        int n1, n2;
+        Mem c1;
+        Mem c2;
+        memset(&c1, 0, sizeof(c1));
+        memset(&c2, 0, sizeof(c2));
+        sqlite3VdbeMemShallowCopy(&c1, pMem1, MEM_Ephem);
+        sqlite3VdbeMemShallowCopy(&c2, pMem2, MEM_Ephem);
+        v1 = sqlite3ValueText((sqlite3_value*)&c1, pColl->enc);
+        n1 = v1==0 ? 0 : c1.n;
+        v2 = sqlite3ValueText((sqlite3_value*)&c2, pColl->enc);
+        n2 = v2==0 ? 0 : c2.n;
+        rc = pColl->xCmp(pColl->pUser, n1, v1, n2, v2);
+        sqlite3VdbeMemRelease(&c1);
+        sqlite3VdbeMemRelease(&c2);
+        return rc;
       }
     }
-    rc = sqlite3ApiExit(db, rc);
-    sqlite3_mutex_leave(db->mutex);
+    /* If a NULL pointer was passed as the collate function, fall through
+    ** to the blob case and use memcmp().  */
+  }
+ 
+  /* Both values must be blobs.  Compare using memcmp().  */
+  rc = memcmp(pMem1->z, pMem2->z, (pMem1->n>pMem2->n)?pMem2->n:pMem1->n);
+  if( rc==0 ){
+    rc = pMem1->n - pMem2->n;
   }
   return rc;
 }
-#endif
-
-/*
-** Extract the user data from a sqlite3_context structure and return a
-** pointer to it.
-*/
-SQLITE_API void *sqlite3_user_data(sqlite3_context *p){
-  assert( p && p->pFunc );
-  return p->pFunc->pUserData;
-}
 
 /*
-** Extract the user data from a sqlite3_context structure and return a
-** pointer to it.
-*/
-SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
-  assert( p && p->pFunc );
-  return p->s.db;
-}
-
-/*
-** The following is the implementation of an SQL function that always
-** fails with an error message stating that the function is used in the
-** wrong context.  The sqlite3_overload_function() API might construct
-** SQL function that use this routine so that the functions will exist
-** for name resolution but are actually overloaded by the xFindFunction
-** method of virtual tables.
+** Move data out of a btree key or data field and into a Mem structure.
+** The data or key is taken from the entry that pCur is currently pointing
+** to.  offset and amt determine what portion of the data or key to retrieve.
+** key is true to get the key or false to get data.  The result is written
+** into the pMem element.
+**
+** The pMem structure is assumed to be uninitialized.  Any prior content
+** is overwritten without being freed.
+**
+** If this routine fails for any reason (malloc returns NULL or unable
+** to read from the disk) then the pMem is left in an inconsistent state.
 */
-SQLITE_PRIVATE void sqlite3InvalidFunction(
-  sqlite3_context *context,  /* The function calling context */
-  int argc,                  /* Number of arguments to the function */
-  sqlite3_value **argv       /* Value of each argument */
+SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(
+  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
+  int offset,       /* Offset from the start of data to return bytes from. */
+  int amt,          /* Number of bytes to return. */
+  int key,          /* If true, retrieve from the btree key, not data. */
+  Mem *pMem         /* OUT: Return data in this Mem structure. */
 ){
-  const char *zName = context->pFunc->zName;
-  char *zErr;
-  zErr = sqlite3MPrintf(0,
-      "unable to use function %s in the requested context", zName);
-  sqlite3_result_error(context, zErr, -1);
-  sqlite3_free(zErr);
+  char *zData;        /* Data from the btree layer */
+  int available = 0;  /* Number of bytes available on the local btree page */
+  int rc = SQLITE_OK; /* Return code */
+
+  assert( sqlite3BtreeCursorIsValid(pCur) );
+
+  /* Note: the calls to BtreeKeyFetch() and DataFetch() below assert() 
+  ** that both the BtShared and database handle mutexes are held. */
+  assert( (pMem->flags & MEM_RowSet)==0 );
+  if( key ){
+    zData = (char *)sqlite3BtreeKeyFetch(pCur, &available);
+  }else{
+    zData = (char *)sqlite3BtreeDataFetch(pCur, &available);
+  }
+  assert( zData!=0 );
+
+  if( offset+amt<=available && (pMem->flags&MEM_Dyn)==0 ){
+    sqlite3VdbeMemRelease(pMem);
+    pMem->z = &zData[offset];
+    pMem->flags = MEM_Blob|MEM_Ephem;
+  }else if( SQLITE_OK==(rc = sqlite3VdbeMemGrow(pMem, amt+2, 0)) ){
+    pMem->flags = MEM_Blob|MEM_Dyn|MEM_Term;
+    pMem->enc = 0;
+    pMem->type = SQLITE_BLOB;
+    if( key ){
+      rc = sqlite3BtreeKey(pCur, offset, amt, pMem->z);
+    }else{
+      rc = sqlite3BtreeData(pCur, offset, amt, pMem->z);
+    }
+    pMem->z[amt] = 0;
+    pMem->z[amt+1] = 0;
+    if( rc!=SQLITE_OK ){
+      sqlite3VdbeMemRelease(pMem);
+    }
+  }
+  pMem->n = amt;
+
+  return rc;
 }
 
-/*
-** Allocate or return the aggregate context for a user function.  A new
-** context is allocated on the first call.  Subsequent calls return the
-** same context that was returned on prior calls.
+/* This function is only available internally, it is not part of the
+** external API. It works in a similar way to sqlite3_value_text(),
+** except the data returned is in the encoding specified by the second
+** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or
+** SQLITE_UTF8.
+**
+** (2006-02-16:)  The enc value can be or-ed with SQLITE_UTF16_ALIGNED.
+** If that is the case, then the result must be aligned on an even byte
+** boundary.
 */
-SQLITE_API void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){
-  Mem *pMem;
-  assert( p && p->pFunc && p->pFunc->xStep );
-  assert( sqlite3_mutex_held(p->s.db->mutex) );
-  pMem = p->pMem;
-  if( (pMem->flags & MEM_Agg)==0 ){
-    if( nByte==0 ){
-      sqlite3VdbeMemReleaseExternal(pMem);
-      pMem->flags = MEM_Null;
-      pMem->z = 0;
-    }else{
-      sqlite3VdbeMemGrow(pMem, nByte, 0);
-      pMem->flags = MEM_Agg;
-      pMem->u.pDef = p->pFunc;
-      if( pMem->z ){
-        memset(pMem->z, 0, nByte);
+SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){
+  if( !pVal ) return 0;
+
+  assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
+  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
+  assert( (pVal->flags & MEM_RowSet)==0 );
+
+  if( pVal->flags&MEM_Null ){
+    return 0;
+  }
+  assert( (MEM_Blob>>3) == MEM_Str );
+  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
+  expandBlob(pVal);
+  if( pVal->flags&MEM_Str ){
+    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
+    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&SQLITE_PTR_TO_INT(pVal->z)) ){
+      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
+      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
+        return 0;
       }
     }
+    sqlite3VdbeMemNulTerminate(pVal);
+  }else{
+    assert( (pVal->flags&MEM_Blob)==0 );
+    sqlite3VdbeMemStringify(pVal, enc);
+    assert( 0==(1&SQLITE_PTR_TO_INT(pVal->z)) );
+  }
+  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
+              || pVal->db->mallocFailed );
+  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
+    return pVal->z;
+  }else{
+    return 0;
   }
-  return (void*)pMem->z;
 }
 
 /*
-** Return the auxilary data pointer, if any, for the iArg'th argument to
-** the user-function defined by pCtx.
+** Create a new sqlite3_value object.
 */
-SQLITE_API void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
-  VdbeFunc *pVdbeFunc;
-
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || iArg>=pVdbeFunc->nAux || iArg<0 ){
-    return 0;
+SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *db){
+  Mem *p = sqlite3DbMallocZero(db, sizeof(*p));
+  if( p ){
+    p->flags = MEM_Null;
+    p->type = SQLITE_NULL;
+    p->db = db;
   }
-  return pVdbeFunc->apAux[iArg].pAux;
+  return p;
 }
 
 /*
-** Set the auxilary data pointer and delete function, for the iArg'th
-** argument to the user-function defined by pCtx. Any previous value is
-** deleted by calling the delete function specified when it was set.
+** Create a new sqlite3_value object, containing the value of pExpr.
+**
+** This only works for very simple expressions that consist of one constant
+** token (i.e. "5", "5.1", "'a string'"). If the expression can
+** be converted directly into a value, then the value is allocated and
+** a pointer written to *ppVal. The caller is responsible for deallocating
+** the value by passing it to sqlite3ValueFree() later on. If the expression
+** cannot be converted to a value, then *ppVal is set to NULL.
 */
-SQLITE_API void sqlite3_set_auxdata(
-  sqlite3_context *pCtx, 
-  int iArg, 
-  void *pAux, 
-  void (*xDelete)(void*)
+SQLITE_PRIVATE int sqlite3ValueFromExpr(
+  sqlite3 *db,              /* The database connection */
+  Expr *pExpr,              /* The expression to evaluate */
+  u8 enc,                   /* Encoding to use */
+  u8 affinity,              /* Affinity to use */
+  sqlite3_value **ppVal     /* Write the new value here */
 ){
-  struct AuxData *pAuxData;
-  VdbeFunc *pVdbeFunc;
-  if( iArg<0 ) goto failed;
+  int op;
+  char *zVal = 0;
+  sqlite3_value *pVal = 0;
 
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
-    int nAux = (pVdbeFunc ? pVdbeFunc->nAux : 0);
-    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
-    pVdbeFunc = sqlite3DbRealloc(pCtx->s.db, pVdbeFunc, nMalloc);
-    if( !pVdbeFunc ){
-      goto failed;
-    }
-    pCtx->pVdbeFunc = pVdbeFunc;
-    memset(&pVdbeFunc->apAux[nAux], 0, sizeof(struct AuxData)*(iArg+1-nAux));
-    pVdbeFunc->nAux = iArg+1;
-    pVdbeFunc->pFunc = pCtx->pFunc;
+  if( !pExpr ){
+    *ppVal = 0;
+    return SQLITE_OK;
   }
-
-  pAuxData = &pVdbeFunc->apAux[iArg];
-  if( pAuxData->pAux && pAuxData->xDelete ){
-    pAuxData->xDelete(pAuxData->pAux);
+  op = pExpr->op;
+  if( op==TK_REGISTER ){
+    op = pExpr->op2;
   }
-  pAuxData->pAux = pAux;
-  pAuxData->xDelete = xDelete;
-  return;
 
-failed:
-  if( xDelete ){
-    xDelete(pAux);
+  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
+    pVal = sqlite3ValueNew(db);
+    if( pVal==0 ) goto no_mem;
+    if( ExprHasProperty(pExpr, EP_IntValue) ){
+      sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue);
+    }else{
+      zVal = sqlite3DbStrDup(db, pExpr->u.zToken);
+      if( zVal==0 ) goto no_mem;
+      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
+      if( op==TK_FLOAT ) pVal->type = SQLITE_FLOAT;
+    }
+    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
+      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
+    }else{
+      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
+    }
+    if( enc!=SQLITE_UTF8 ){
+      sqlite3VdbeChangeEncoding(pVal, enc);
+    }
+  }else if( op==TK_UMINUS ) {
+    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) ){
+      pVal->u.i = -1 * pVal->u.i;
+      /* (double)-1 In case of SQLITE_OMIT_FLOATING_POINT... */
+      pVal->r = (double)-1 * pVal->r;
+    }
   }
-}
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+  else if( op==TK_BLOB ){
+    int nVal;
+    assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
+    assert( pExpr->u.zToken[1]=='\'' );
+    pVal = sqlite3ValueNew(db);
+    if( !pVal ) goto no_mem;
+    zVal = &pExpr->u.zToken[2];
+    nVal = sqlite3Strlen30(zVal)-1;
+    assert( zVal[nVal]=='\'' );
+    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
+                         0, SQLITE_DYNAMIC);
+  }
+#endif
 
-/*
-** Return the number of times the Step function of a aggregate has been 
-** called.
-**
-** This function is deprecated.  Do not use it for new code.  It is
-** provide only to avoid breaking legacy code.  New aggregate function
-** implementations should keep their own counts within their aggregate
-** context.
-*/
-SQLITE_API int sqlite3_aggregate_count(sqlite3_context *p){
-  assert( p && p->pFunc && p->pFunc->xStep );
-  return p->pMem->n;
+  *ppVal = pVal;
+  return SQLITE_OK;
+
+no_mem:
+  db->mallocFailed = 1;
+  sqlite3DbFree(db, zVal);
+  sqlite3ValueFree(pVal);
+  *ppVal = 0;
+  return SQLITE_NOMEM;
 }
 
 /*
-** Return the number of columns in the result set for the statement pStmt.
+** Change the string value of an sqlite3_value object
 */
-SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt){
-  Vdbe *pVm = (Vdbe *)pStmt;
-  return pVm ? pVm->nResColumn : 0;
+SQLITE_PRIVATE void sqlite3ValueSetStr(
+  sqlite3_value *v,     /* Value to be set */
+  int n,                /* Length of string z */
+  const void *z,        /* Text of the new string */
+  u8 enc,               /* Encoding to use */
+  void (*xDel)(void*)   /* Destructor for the string */
+){
+  if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel);
 }
 
 /*
-** Return the number of values available from the current row of the
-** currently executing statement pStmt.
+** Free an sqlite3_value object
 */
-SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt){
-  Vdbe *pVm = (Vdbe *)pStmt;
-  if( pVm==0 || pVm->pResultSet==0 ) return 0;
-  return pVm->nResColumn;
+SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value *v){
+  if( !v ) return;
+  sqlite3VdbeMemRelease((Mem *)v);
+  sqlite3DbFree(((Mem*)v)->db, v);
 }
 
-
 /*
-** Check to see if column iCol of the given statement is valid.  If
-** it is, return a pointer to the Mem for the value of that column.
-** If iCol is not valid, return a pointer to a Mem which has a value
-** of NULL.
+** Return the number of bytes in the sqlite3_value object assuming
+** that it uses the encoding "enc"
 */
-static Mem *columnMem(sqlite3_stmt *pStmt, int i){
-  Vdbe *pVm;
-  int vals;
-  Mem *pOut;
-
-  pVm = (Vdbe *)pStmt;
-  if( pVm && pVm->pResultSet!=0 && i<pVm->nResColumn && i>=0 ){
-    sqlite3_mutex_enter(pVm->db->mutex);
-    vals = sqlite3_data_count(pStmt);
-    pOut = &pVm->pResultSet[i];
-  }else{
-    static const Mem nullMem = {{0}, 0.0, 0, "", 0, MEM_Null, SQLITE_NULL, 0, 0, 0 };
-    if( pVm->db ){
-      sqlite3_mutex_enter(pVm->db->mutex);
-      sqlite3Error(pVm->db, SQLITE_RANGE, 0);
+SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){
+  Mem *p = (Mem*)pVal;
+  if( (p->flags & MEM_Blob)!=0 || sqlite3ValueText(pVal, enc) ){
+    if( p->flags & MEM_Zero ){
+      return p->n + p->u.nZero;
+    }else{
+      return p->n;
     }
-    pOut = (Mem*)&nullMem;
   }
-  return pOut;
+  return 0;
 }
 
+/************** End of vdbemem.c *********************************************/
+/************** Begin file vdbeaux.c *****************************************/
 /*
-** This function is called after invoking an sqlite3_value_XXX function on a 
-** column value (i.e. a value returned by evaluating an SQL expression in the
-** select list of a SELECT statement) that may cause a malloc() failure. If 
-** malloc() has failed, the threads mallocFailed flag is cleared and the result
-** code of statement pStmt set to SQLITE_NOMEM.
+** 2003 September 6
 **
-** Specifically, this is called from within:
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-**     sqlite3_column_int()
-**     sqlite3_column_int64()
-**     sqlite3_column_text()
-**     sqlite3_column_text16()
-**     sqlite3_column_real()
-**     sqlite3_column_bytes()
-**     sqlite3_column_bytes16()
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** But not for sqlite3_column_blob(), which never calls malloc().
+*************************************************************************
+** This file contains code used for creating, destroying, and populating
+** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
+** to version 2.8.7, all this code was combined into the vdbe.c source file.
+** But that file was getting too big so this subroutines were split out.
+**
+** $Id: vdbeaux.c,v 1.480 2009/08/08 18:01:08 drh Exp $
 */
-static void columnMallocFailure(sqlite3_stmt *pStmt)
-{
-  /* If malloc() failed during an encoding conversion within an
-  ** sqlite3_column_XXX API, then set the return code of the statement to
-  ** SQLITE_NOMEM. The next call to _step() (if any) will return SQLITE_ERROR
-  ** and _finalize() will return NOMEM.
-  */
-  Vdbe *p = (Vdbe *)pStmt;
-  if( p ){
-    p->rc = sqlite3ApiExit(p->db, p->rc);
-    sqlite3_mutex_leave(p->db->mutex);
-  }
-}
 
-/**************************** sqlite3_column_  *******************************
-** The following routines are used to access elements of the current row
-** in the result set.
-*/
-SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt *pStmt, int i){
-  const void *val;
-  val = sqlite3_value_blob( columnMem(pStmt,i) );
-  /* Even though there is no encoding conversion, value_blob() might
-  ** need to call malloc() to expand the result of a zeroblob() 
-  ** expression. 
-  */
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API int sqlite3_column_bytes(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_bytes( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_bytes16( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API double sqlite3_column_double(sqlite3_stmt *pStmt, int i){
-  double val = sqlite3_value_double( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API int sqlite3_column_int(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_int( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API sqlite_int64 sqlite3_column_int64(sqlite3_stmt *pStmt, int i){
-  sqlite_int64 val = sqlite3_value_int64( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt *pStmt, int i){
-  const unsigned char *val = sqlite3_value_text( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt *pStmt, int i){
-  sqlite3_value *pOut = columnMem(pStmt, i);
-  columnMallocFailure(pStmt);
-  return pOut;
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt *pStmt, int i){
-  const void *val = sqlite3_value_text16( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-#endif /* SQLITE_OMIT_UTF16 */
-SQLITE_API int sqlite3_column_type(sqlite3_stmt *pStmt, int i){
-  int iType = sqlite3_value_type( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return iType;
-}
 
-/* The following function is experimental and subject to change or
-** removal */
-/*int sqlite3_column_numeric_type(sqlite3_stmt *pStmt, int i){
-**  return sqlite3_value_numeric_type( columnMem(pStmt,i) );
-**}
-*/
 
 /*
-** Convert the N-th element of pStmt->pColName[] into a string using
-** xFunc() then return that string.  If N is out of range, return 0.
-**
-** There are up to 5 names for each column.  useType determines which
-** name is returned.  Here are the names:
-**
-**    0      The column name as it should be displayed for output
-**    1      The datatype name for the column
-**    2      The name of the database that the column derives from
-**    3      The name of the table that the column derives from
-**    4      The name of the table column that the result column derives from
-**
-** If the result is not a simple column reference (if it is an expression
-** or a constant) then useTypes 2, 3, and 4 return NULL.
+** When debugging the code generator in a symbolic debugger, one can
+** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
+** as they are added to the instruction stream.
 */
-static const void *columnName(
-  sqlite3_stmt *pStmt,
-  int N,
-  const void *(*xFunc)(Mem*),
-  int useType
-){
-  const void *ret = 0;
-  Vdbe *p = (Vdbe *)pStmt;
-  int n;
-  
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3VdbeAddopTrace = 0;
+#endif
 
-  if( p!=0 ){
-    n = sqlite3_column_count(pStmt);
-    if( N<n && N>=0 ){
-      N += useType*n;
-      sqlite3_mutex_enter(p->db->mutex);
-      ret = xFunc(&p->aColName[N]);
-
-      /* A malloc may have failed inside of the xFunc() call. If this
-      ** is the case, clear the mallocFailed flag and return NULL.
-      */
-      if( p->db && p->db->mallocFailed ){
-        p->db->mallocFailed = 0;
-        ret = 0;
-      }
-      sqlite3_mutex_leave(p->db->mutex);
-    }
-  }
-  return ret;
-}
 
 /*
-** Return the name of the Nth column of the result set returned by SQL
-** statement pStmt.
+** Create a new virtual database engine.
 */
-SQLITE_API const char *sqlite3_column_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_NAME);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_NAME);
+SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(sqlite3 *db){
+  Vdbe *p;
+  p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
+  if( p==0 ) return 0;
+  p->db = db;
+  if( db->pVdbe ){
+    db->pVdbe->pPrev = p;
+  }
+  p->pNext = db->pVdbe;
+  p->pPrev = 0;
+  db->pVdbe = p;
+  p->magic = VDBE_MAGIC_INIT;
+  return p;
 }
-#endif
 
 /*
-** Constraint:  If you have ENABLE_COLUMN_METADATA then you must
-** not define OMIT_DECLTYPE.
+** Remember the SQL string for a prepared statement.
 */
-#if defined(SQLITE_OMIT_DECLTYPE) && defined(SQLITE_ENABLE_COLUMN_METADATA)
-# error "Must not define both SQLITE_OMIT_DECLTYPE \
-         and SQLITE_ENABLE_COLUMN_METADATA"
+SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, int isPrepareV2){
+  if( p==0 ) return;
+#ifdef SQLITE_OMIT_TRACE
+  if( !isPrepareV2 ) return;
 #endif
-
-#ifndef SQLITE_OMIT_DECLTYPE
-/*
-** Return the column declaration type (if applicable) of the 'i'th column
-** of the result set of SQL statement pStmt.
-*/
-SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DECLTYPE);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DECLTYPE);
+  assert( p->zSql==0 );
+  p->zSql = sqlite3DbStrNDup(p->db, z, n);
+  p->isPrepareV2 = isPrepareV2 ? 1 : 0;
 }
-#endif /* SQLITE_OMIT_UTF16 */
-#endif /* SQLITE_OMIT_DECLTYPE */
 
-#ifdef SQLITE_ENABLE_COLUMN_METADATA
 /*
-** Return the name of the database from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
+** Return the SQL associated with a prepared statement
 */
-SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DATABASE);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DATABASE);
+SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt){
+  Vdbe *p = (Vdbe *)pStmt;
+  return (p->isPrepareV2 ? p->zSql : 0);
 }
-#endif /* SQLITE_OMIT_UTF16 */
 
 /*
-** Return the name of the table from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
+** Swap all content between two VDBE structures.
 */
-SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_TABLE);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_TABLE);
+SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
+  Vdbe tmp, *pTmp;
+  char *zTmp;
+  tmp = *pA;
+  *pA = *pB;
+  *pB = tmp;
+  pTmp = pA->pNext;
+  pA->pNext = pB->pNext;
+  pB->pNext = pTmp;
+  pTmp = pA->pPrev;
+  pA->pPrev = pB->pPrev;
+  pB->pPrev = pTmp;
+  zTmp = pA->zSql;
+  pA->zSql = pB->zSql;
+  pB->zSql = zTmp;
+  pB->isPrepareV2 = pA->isPrepareV2;
 }
-#endif /* SQLITE_OMIT_UTF16 */
 
+#ifdef SQLITE_DEBUG
 /*
-** Return the name of the table column from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
+** Turn tracing on or off
 */
-SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_COLUMN);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_COLUMN);
+SQLITE_PRIVATE void sqlite3VdbeTrace(Vdbe *p, FILE *trace){
+  p->trace = trace;
 }
-#endif /* SQLITE_OMIT_UTF16 */
-#endif /* SQLITE_ENABLE_COLUMN_METADATA */
-
+#endif
 
-/******************************* sqlite3_bind_  ***************************
-** 
-** Routines used to attach values to wildcards in a compiled SQL statement.
-*/
 /*
-** Unbind the value bound to variable i in virtual machine p. This is the 
-** the same as binding a NULL value to the column. If the "i" parameter is
-** out of range, then SQLITE_RANGE is returned. Othewise SQLITE_OK.
+** Resize the Vdbe.aOp array so that it is at least one op larger than 
+** it was.
 **
-** The error code stored in database p->db is overwritten with the return
-** value in any case.
+** If an out-of-memory error occurs while resizing the array, return
+** SQLITE_NOMEM. In this case Vdbe.aOp and Vdbe.nOpAlloc remain 
+** unchanged (this is so that any opcodes already allocated can be 
+** correctly deallocated along with the rest of the Vdbe).
 */
-static int vdbeUnbind(Vdbe *p, int i){
-  Mem *pVar;
-  if( p==0 || p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
-    if( p ) sqlite3Error(p->db, SQLITE_MISUSE, 0);
-    return SQLITE_MISUSE;
-  }
-  if( i<1 || i>p->nVar ){
-    sqlite3Error(p->db, SQLITE_RANGE, 0);
-    return SQLITE_RANGE;
+static int growOpArray(Vdbe *p){
+  VdbeOp *pNew;
+  int nNew = (p->nOpAlloc ? p->nOpAlloc*2 : (int)(1024/sizeof(Op)));
+  pNew = sqlite3DbRealloc(p->db, p->aOp, nNew*sizeof(Op));
+  if( pNew ){
+    p->nOpAlloc = sqlite3DbMallocSize(p->db, pNew)/sizeof(Op);
+    p->aOp = pNew;
   }
-  i--;
-  pVar = &p->aVar[i];
-  sqlite3VdbeMemRelease(pVar);
-  pVar->flags = MEM_Null;
-  sqlite3Error(p->db, SQLITE_OK, 0);
-  return SQLITE_OK;
+  return (pNew ? SQLITE_OK : SQLITE_NOMEM);
 }
 
 /*
-** Bind a text or BLOB value.
+** Add a new instruction to the list of instructions current in the
+** VDBE.  Return the address of the new instruction.
+**
+** Parameters:
+**
+**    p               Pointer to the VDBE
+**
+**    op              The opcode for this instruction
+**
+**    p1, p2, p3      Operands
+**
+** Use the sqlite3VdbeResolveLabel() function to fix an address and
+** the sqlite3VdbeChangeP4() function to change the value of the P4
+** operand.
 */
-static int bindText(
-  sqlite3_stmt *pStmt,   /* The statement to bind against */
-  int i,                 /* Index of the parameter to bind */
-  const void *zData,     /* Pointer to the data to be bound */
-  int nData,             /* Number of bytes of data to be bound */
-  void (*xDel)(void*),   /* Destructor for the data */
-  int encoding           /* Encoding for the data */
-){
-  Vdbe *p = (Vdbe *)pStmt;
-  Mem *pVar;
-  int rc;
+SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
+  int i;
+  VdbeOp *pOp;
 
-  if( p==0 ){
-    return SQLITE_MISUSE;
-  }
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK && zData!=0 ){
-    pVar = &p->aVar[i-1];
-    rc = sqlite3VdbeMemSetStr(pVar, zData, nData, encoding, xDel);
-    if( rc==SQLITE_OK && encoding!=0 ){
-      rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
+  i = p->nOp;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  assert( op>0 && op<0xff );
+  if( p->nOpAlloc<=i ){
+    if( growOpArray(p) ){
+      return 1;
     }
-    sqlite3Error(p->db, rc, 0);
-    rc = sqlite3ApiExit(p->db, rc);
   }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
+  p->nOp++;
+  pOp = &p->aOp[i];
+  pOp->opcode = (u8)op;
+  pOp->p5 = 0;
+  pOp->p1 = p1;
+  pOp->p2 = p2;
+  pOp->p3 = p3;
+  pOp->p4.p = 0;
+  pOp->p4type = P4_NOTUSED;
+  p->expired = 0;
+#ifdef SQLITE_DEBUG
+  pOp->zComment = 0;
+  if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
+#endif
+#ifdef VDBE_PROFILE
+  pOp->cycles = 0;
+  pOp->cnt = 0;
+#endif
+  return i;
+}
+SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe *p, int op){
+  return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
+}
+SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
+  return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
+}
+SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
+  return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
 }
 
 
 /*
-** Bind a blob value to an SQL statement variable.
+** Add an opcode that includes the p4 value as a pointer.
 */
-SQLITE_API int sqlite3_bind_blob(
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const void *zData, 
-  int nData, 
-  void (*xDel)(void*)
-){
-  return bindText(pStmt, i, zData, nData, xDel, 0);
-}
-SQLITE_API int sqlite3_bind_double(sqlite3_stmt *pStmt, int i, double rValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetDouble(&p->aVar[i-1], rValue);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-SQLITE_API int sqlite3_bind_int(sqlite3_stmt *p, int i, int iValue){
-  return sqlite3_bind_int64(p, i, (i64)iValue);
-}
-SQLITE_API int sqlite3_bind_int64(sqlite3_stmt *pStmt, int i, sqlite_int64 iValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetInt64(&p->aVar[i-1], iValue);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-SQLITE_API int sqlite3_bind_null(sqlite3_stmt *pStmt, int i){
-  int rc;
-  Vdbe *p = (Vdbe*)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-SQLITE_API int sqlite3_bind_text( 
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const char *zData, 
-  int nData, 
-  void (*xDel)(void*)
-){
-  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF8);
-}
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API int sqlite3_bind_text16(
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const void *zData, 
-  int nData, 
-  void (*xDel)(void*)
+SQLITE_PRIVATE int sqlite3VdbeAddOp4(
+  Vdbe *p,            /* Add the opcode to this VM */
+  int op,             /* The new opcode */
+  int p1,             /* The P1 operand */
+  int p2,             /* The P2 operand */
+  int p3,             /* The P3 operand */
+  const char *zP4,    /* The P4 operand */
+  int p4type          /* P4 operand type */
 ){
-  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF16NATIVE);
+  int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
+  sqlite3VdbeChangeP4(p, addr, zP4, p4type);
+  return addr;
 }
-#endif /* SQLITE_OMIT_UTF16 */
-SQLITE_API int sqlite3_bind_value(sqlite3_stmt *pStmt, int i, const sqlite3_value *pValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    rc = sqlite3VdbeMemCopy(&p->aVar[i-1], pValue);
+
+/*
+** Create a new symbolic label for an instruction that has yet to be
+** coded.  The symbolic label is really just a negative number.  The
+** label can be used as the P2 value of an operation.  Later, when
+** the label is resolved to a specific address, the VDBE will scan
+** through its operation list and change all values of P2 which match
+** the label into the resolved address.
+**
+** The VDBE knows that a P2 value is a label because labels are
+** always negative and P2 values are suppose to be non-negative.
+** Hence, a negative P2 value is a label that has yet to be resolved.
+**
+** Zero is returned if a malloc() fails.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe *p){
+  int i;
+  i = p->nLabel++;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  if( i>=p->nLabelAlloc ){
+    int n = p->nLabelAlloc*2 + 5;
+    p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
+                                       n*sizeof(p->aLabel[0]));
+    p->nLabelAlloc = sqlite3DbMallocSize(p->db, p->aLabel)/sizeof(p->aLabel[0]);
   }
-  rc = sqlite3ApiExit(p->db, rc);
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt *pStmt, int i, int n){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetZeroBlob(&p->aVar[i-1], n);
+  if( p->aLabel ){
+    p->aLabel[i] = -1;
   }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
+  return -1-i;
 }
 
 /*
-** Return the number of wildcards that can be potentially bound to.
-** This routine is added to support DBD::SQLite.  
+** Resolve label "x" to be the address of the next instruction to
+** be inserted.  The parameter "x" must have been obtained from
+** a prior call to sqlite3VdbeMakeLabel().
 */
-SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt *pStmt){
-  Vdbe *p = (Vdbe*)pStmt;
-  return p ? p->nVar : 0;
+SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe *p, int x){
+  int j = -1-x;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  assert( j>=0 && j<p->nLabel );
+  if( p->aLabel ){
+    p->aLabel[j] = p->nOp;
+  }
 }
 
+#ifdef SQLITE_DEBUG /* sqlite3AssertMayAbort() logic */
+
 /*
-** Create a mapping from variable numbers to variable names
-** in the Vdbe.azVar[] array, if such a mapping does not already
-** exist.
+** The following type and function are used to iterate through all opcodes
+** in a Vdbe main program and each of the sub-programs (triggers) it may 
+** invoke directly or indirectly. It should be used as follows:
+**
+**   Op *pOp;
+**   VdbeOpIter sIter;
+**
+**   memset(&sIter, 0, sizeof(sIter));
+**   sIter.v = v;                            // v is of type Vdbe* 
+**   while( (pOp = opIterNext(&sIter)) ){
+**     // Do something with pOp
+**   }
+**   sqlite3DbFree(v->db, sIter.apSub);
+** 
 */
-static void createVarMap(Vdbe *p){
-  if( !p->okVar ){
-    sqlite3_mutex_enter(p->db->mutex);
-    if( !p->okVar ){
+typedef struct VdbeOpIter VdbeOpIter;
+struct VdbeOpIter {
+  Vdbe *v;                   /* Vdbe to iterate through the opcodes of */
+  SubProgram **apSub;        /* Array of subprograms */
+  int nSub;                  /* Number of entries in apSub */
+  int iAddr;                 /* Address of next instruction to return */
+  int iSub;                  /* 0 = main program, 1 = first sub-program etc. */
+};
+static Op *opIterNext(VdbeOpIter *p){
+  Vdbe *v = p->v;
+  Op *pRet = 0;
+  Op *aOp;
+  int nOp;
+
+  if( p->iSub<=p->nSub ){
+
+    if( p->iSub==0 ){
+      aOp = v->aOp;
+      nOp = v->nOp;
+    }else{
+      aOp = p->apSub[p->iSub-1]->aOp;
+      nOp = p->apSub[p->iSub-1]->nOp;
+    }
+    assert( p->iAddr<nOp );
+
+    pRet = &aOp[p->iAddr];
+    p->iAddr++;
+    if( p->iAddr==nOp ){
+      p->iSub++;
+      p->iAddr = 0;
+    }
+  
+    if( pRet->p4type==P4_SUBPROGRAM ){
+      int nByte = (p->nSub+1)*sizeof(SubProgram*);
       int j;
-      Op *pOp;
-      for(j=0, pOp=p->aOp; j<p->nOp; j++, pOp++){
-        if( pOp->opcode==OP_Variable ){
-          assert( pOp->p1>0 && pOp->p1<=p->nVar );
-          p->azVar[pOp->p1-1] = pOp->p4.z;
+      for(j=0; j<p->nSub; j++){
+        if( p->apSub[j]==pRet->p4.pProgram ) break;
+      }
+      if( j==p->nSub ){
+        p->apSub = sqlite3DbReallocOrFree(v->db, p->apSub, nByte);
+        if( !p->apSub ){
+          pRet = 0;
+        }else{
+          p->apSub[p->nSub++] = pRet->p4.pProgram;
         }
       }
-      p->okVar = 1;
     }
-    sqlite3_mutex_leave(p->db->mutex);
   }
+
+  return pRet;
 }
 
 /*
-** Return the name of a wildcard parameter.  Return NULL if the index
-** is out of range or if the wildcard is unnamed.
+** Check if the program stored in the VM associated with pParse may
+** throw an ABORT exception (causing the statement, but not entire transaction
+** to be rolled back). This condition is true if the main program or any
+** sub-programs contains any of the following:
 **
-** The result is always UTF-8.
+**   *  OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
+**   *  OP_HaltIfNull with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
+**   *  OP_Destroy
+**   *  OP_VUpdate
+**   *  OP_VRename
+**   *  OP_FkCounter with P2==0 (immediate foreign key constraint)
+**
+** Then check that the value of Parse.mayAbort is true if an
+** ABORT may be thrown, or false otherwise. Return true if it does
+** match, or false otherwise. This function is intended to be used as
+** part of an assert statement in the compiler. Similar to:
+**
+**   assert( sqlite3VdbeAssertMayAbort(pParse->pVdbe, pParse->mayAbort) );
 */
-SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt *pStmt, int i){
-  Vdbe *p = (Vdbe*)pStmt;
-  if( p==0 || i<1 || i>p->nVar ){
-    return 0;
+SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
+  int hasAbort = 0;
+  Op *pOp;
+  VdbeOpIter sIter;
+  memset(&sIter, 0, sizeof(sIter));
+  sIter.v = v;
+
+  while( (pOp = opIterNext(&sIter))!=0 ){
+    int opcode = pOp->opcode;
+    if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename 
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+     || (opcode==OP_FkCounter && pOp->p1==0 && pOp->p2==1) 
+#endif
+     || ((opcode==OP_Halt || opcode==OP_HaltIfNull) 
+      && (pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
+    ){
+      hasAbort = 1;
+      break;
+    }
   }
-  createVarMap(p);
-  return p->azVar[i-1];
+  sqlite3DbFree(v->db, sIter.apSub);
+
+  /* Return true if hasAbort==mayAbort. Or if a malloc failure occured.
+  ** If malloc failed, then the while() loop above may not have iterated
+  ** through all opcodes and hasAbort may be set incorrectly. Return
+  ** true for this case to prevent the assert() in the callers frame
+  ** from failing.  */
+  return ( v->db->mallocFailed || hasAbort==mayAbort );
 }
+#endif /* SQLITE_DEBUG - the sqlite3AssertMayAbort() function */
 
 /*
-** Given a wildcard parameter name, return the index of the variable
-** with that name.  If there is no variable with the given name,
-** return 0.
+** Loop through the program looking for P2 values that are negative
+** on jump instructions.  Each such value is a label.  Resolve the
+** label by setting the P2 value to its correct non-zero value.
+**
+** This routine is called once after all opcodes have been inserted.
+**
+** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument 
+** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by 
+** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
 */
-SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt *pStmt, const char *zName){
-  Vdbe *p = (Vdbe*)pStmt;
+static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
   int i;
-  if( p==0 ){
-    return 0;
-  }
-  createVarMap(p); 
-  if( zName ){
-    for(i=0; i<p->nVar; i++){
-      const char *z = p->azVar[i];
-      if( z && strcmp(z,zName)==0 ){
-        return i+1;
-      }
+  int nMaxArgs = *pMaxFuncArgs;
+  Op *pOp;
+  int *aLabel = p->aLabel;
+  p->readOnly = 1;
+  for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
+    u8 opcode = pOp->opcode;
+
+    if( opcode==OP_Function || opcode==OP_AggStep ){
+      if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    }else if( opcode==OP_VUpdate ){
+      if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
+#endif
+    }else if( opcode==OP_Transaction && pOp->p2!=0 ){
+      p->readOnly = 0;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    }else if( opcode==OP_VFilter ){
+      int n;
+      assert( p->nOp - i >= 3 );
+      assert( pOp[-1].opcode==OP_Integer );
+      n = pOp[-1].p1;
+      if( n>nMaxArgs ) nMaxArgs = n;
+#endif
     }
-  }
-  return 0;
-}
 
-/*
-** Transfer all bindings from the first statement over to the second.
-** If the two statements contain a different number of bindings, then
-** an SQLITE_ERROR is returned.
-*/
-SQLITE_API int sqlite3_transfer_bindings(sqlite3_stmt *pFromStmt, sqlite3_stmt *pToStmt){
-  Vdbe *pFrom = (Vdbe*)pFromStmt;
-  Vdbe *pTo = (Vdbe*)pToStmt;
-  int i, rc = SQLITE_OK;
-  if( (pFrom->magic!=VDBE_MAGIC_RUN && pFrom->magic!=VDBE_MAGIC_HALT)
-    || (pTo->magic!=VDBE_MAGIC_RUN && pTo->magic!=VDBE_MAGIC_HALT)
-    || pTo->db!=pFrom->db ){
-    return SQLITE_MISUSE;
-  }
-  if( pFrom->nVar!=pTo->nVar ){
-    return SQLITE_ERROR;
-  }
-  sqlite3_mutex_enter(pTo->db->mutex);
-  for(i=0; rc==SQLITE_OK && i<pFrom->nVar; i++){
-    sqlite3VdbeMemMove(&pTo->aVar[i], &pFrom->aVar[i]);
+    if( sqlite3VdbeOpcodeHasProperty(opcode, OPFLG_JUMP) && pOp->p2<0 ){
+      assert( -1-pOp->p2<p->nLabel );
+      pOp->p2 = aLabel[-1-pOp->p2];
+    }
   }
-  sqlite3_mutex_leave(pTo->db->mutex);
-  assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
-  return rc;
+  sqlite3DbFree(p->db, p->aLabel);
+  p->aLabel = 0;
+
+  *pMaxFuncArgs = nMaxArgs;
 }
 
 /*
-** Return the sqlite3* database handle to which the prepared statement given
-** in the argument belongs.  This is the same database handle that was
-** the first argument to the sqlite3_prepare() that was used to create
-** the statement in the first place.
+** Return the address of the next instruction to be inserted.
 */
-SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt *pStmt){
-  return pStmt ? ((Vdbe*)pStmt)->db : 0;
+SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe *p){
+  assert( p->magic==VDBE_MAGIC_INIT );
+  return p->nOp;
 }
 
-/************** End of vdbeapi.c *********************************************/
-/************** Begin file vdbe.c ********************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** This function returns a pointer to the array of opcodes associated with
+** the Vdbe passed as the first argument. It is the callers responsibility
+** to arrange for the returned array to be eventually freed using the 
+** vdbeFreeOpArray() function.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** The code in this file implements execution method of the 
-** Virtual Database Engine (VDBE).  A separate file ("vdbeaux.c")
-** handles housekeeping details such as creating and deleting
-** VDBE instances.  This file is solely interested in executing
-** the VDBE program.
-**
-** In the external interface, an "sqlite3_stmt*" is an opaque pointer
-** to a VDBE.
-**
-** The SQL parser generates a program which is then executed by
-** the VDBE to do the work of the SQL statement.  VDBE programs are 
-** similar in form to assembly language.  The program consists of
-** a linear sequence of operations.  Each operation has an opcode 
-** and 5 operands.  Operands P1, P2, and P3 are integers.  Operand P4 
-** is a null-terminated string.  Operand P5 is an unsigned character.
-** Few opcodes use all 5 operands.
-**
-** Computation results are stored on a set of registers numbered beginning
-** with 1 and going up to Vdbe.nMem.  Each register can store
-** either an integer, a null-terminated string, a floating point
-** number, or the SQL "NULL" value.  An inplicit conversion from one
-** type to the other occurs as necessary.
-** 
-** Most of the code in this file is taken up by the sqlite3VdbeExec()
-** function which does the work of interpreting a VDBE program.
-** But other routines are also provided to help in building up
-** a program instruction by instruction.
-**
-** Various scripts scan this source file in order to generate HTML
-** documentation, headers files, or other derived files.  The formatting
-** of the code in this file is, therefore, important.  See other comments
-** in this file for details.  If in doubt, do not deviate from existing
-** commenting and indentation practices when changing or adding code.
-**
-** $Id: vdbe.c,v 1.740 2008/05/13 13:27:34 drh Exp $
+** Before returning, *pnOp is set to the number of entries in the returned
+** array. Also, *pnMaxArg is set to the larger of its current value and 
+** the number of entries in the Vdbe.apArg[] array required to execute the 
+** returned program.
 */
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe *p, int *pnOp, int *pnMaxArg){
+  VdbeOp *aOp = p->aOp;
+  assert( aOp && !p->db->mallocFailed );
+
+  /* Check that sqlite3VdbeUsesBtree() was not called on this VM */
+  assert( p->aMutex.nMutex==0 );
+
+  resolveP2Values(p, pnMaxArg);
+  *pnOp = p->nOp;
+  p->aOp = 0;
+  return aOp;
+}
 
 /*
-** The following global variable is incremented every time a cursor
-** moves, either by the OP_MoveXX, OP_Next, or OP_Prev opcodes.  The test
-** procedures use this information to make sure that indices are
-** working correctly.  This variable has no function other than to
-** help verify the correct operation of the library.
+** Add a whole list of operations to the operation stack.  Return the
+** address of the first operation added.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_search_count = 0;
+SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
+  int addr;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  if( p->nOp + nOp > p->nOpAlloc && growOpArray(p) ){
+    return 0;
+  }
+  addr = p->nOp;
+  if( ALWAYS(nOp>0) ){
+    int i;
+    VdbeOpList const *pIn = aOp;
+    for(i=0; i<nOp; i++, pIn++){
+      int p2 = pIn->p2;
+      VdbeOp *pOut = &p->aOp[i+addr];
+      pOut->opcode = pIn->opcode;
+      pOut->p1 = pIn->p1;
+      if( p2<0 && sqlite3VdbeOpcodeHasProperty(pOut->opcode, OPFLG_JUMP) ){
+        pOut->p2 = addr + ADDR(p2);
+      }else{
+        pOut->p2 = p2;
+      }
+      pOut->p3 = pIn->p3;
+      pOut->p4type = P4_NOTUSED;
+      pOut->p4.p = 0;
+      pOut->p5 = 0;
+#ifdef SQLITE_DEBUG
+      pOut->zComment = 0;
+      if( sqlite3VdbeAddopTrace ){
+        sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
+      }
 #endif
+    }
+    p->nOp += nOp;
+  }
+  return addr;
+}
 
 /*
-** When this global variable is positive, it gets decremented once before
-** each instruction in the VDBE.  When reaches zero, the u1.isInterrupted
-** field of the sqlite3 structure is set in order to simulate and interrupt.
-**
-** This facility is used for testing purposes only.  It does not function
-** in an ordinary build.
+** Change the value of the P1 operand for a specific instruction.
+** This routine is useful when a large program is loaded from a
+** static array using sqlite3VdbeAddOpList but we want to make a
+** few minor changes to the program.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_interrupt_count = 0;
-#endif
+SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
+  assert( p!=0 );
+  assert( addr>=0 );
+  if( p->nOp>addr ){
+    p->aOp[addr].p1 = val;
+  }
+}
 
 /*
-** The next global variable is incremented each type the OP_Sort opcode
-** is executed.  The test procedures use this information to make sure that
-** sorting is occurring or not occuring at appropriate times.   This variable
-** has no function other than to help verify the correct operation of the
-** library.
+** Change the value of the P2 operand for a specific instruction.
+** This routine is useful for setting a jump destination.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_sort_count = 0;
-#endif
+SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
+  assert( p!=0 );
+  assert( addr>=0 );
+  if( p->nOp>addr ){
+    p->aOp[addr].p2 = val;
+  }
+}
 
 /*
-** The next global variable records the size of the largest MEM_Blob
-** or MEM_Str that has been used by a VDBE opcode.  The test procedures
-** use this information to make sure that the zero-blob functionality
-** is working correctly.   This variable has no function other than to
-** help verify the correct operation of the library.
+** Change the value of the P3 operand for a specific instruction.
 */
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_max_blobsize = 0;
-static void updateMaxBlobsize(Mem *p){
-  if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
-    sqlite3_max_blobsize = p->n;
+SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
+  assert( p!=0 );
+  assert( addr>=0 );
+  if( p->nOp>addr ){
+    p->aOp[addr].p3 = val;
   }
 }
-#endif
 
 /*
-** Test a register to see if it exceeds the current maximum blob size.
-** If it does, record the new maximum blob size.
-*/
-#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
-# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
-#else
-# define UPDATE_MAX_BLOBSIZE(P)
-#endif
-
-/*
-** Release the memory associated with a register.  This
-** leaves the Mem.flags field in an inconsistent state.
-*/
-#define Release(P) if((P)->flags&MEM_Dyn){ sqlite3VdbeMemRelease(P); }
-
-/*
-** Convert the given register into a string if it isn't one
-** already. Return non-zero if a malloc() fails.
+** Change the value of the P5 operand for the most recently
+** added operation.
 */
-#define Stringify(P, enc) \
-   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
-     { goto no_mem; }
+SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
+  assert( p!=0 );
+  if( p->aOp ){
+    assert( p->nOp>0 );
+    p->aOp[p->nOp-1].p5 = val;
+  }
+}
 
 /*
-** An ephemeral string value (signified by the MEM_Ephem flag) contains
-** a pointer to a dynamically allocated string where some other entity
-** is responsible for deallocating that string.  Because the register
-** does not control the string, it might be deleted without the register
-** knowing it.
-**
-** This routine converts an ephemeral string into a dynamically allocated
-** string that the register itself controls.  In other words, it
-** converts an MEM_Ephem string into an MEM_Dyn string.
+** Change the P2 operand of instruction addr so that it points to
+** the address of the next instruction to be coded.
 */
-#define Deephemeralize(P) \
-   if( ((P)->flags&MEM_Ephem)!=0 \
-       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
+SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe *p, int addr){
+  sqlite3VdbeChangeP2(p, addr, p->nOp);
+}
 
-/*
-** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
-** P if required.
-*/
-#define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
 
 /*
-** Argument pMem points at a regiser that will be passed to a
-** user-defined function or returned to the user as the result of a query.
-** The second argument, 'db_enc' is the text encoding used by the vdbe for
-** register variables.  This routine sets the pMem->enc and pMem->type
-** variables used by the sqlite3_value_*() routines.
+** If the input FuncDef structure is ephemeral, then free it.  If
+** the FuncDef is not ephermal, then do nothing.
 */
-#define storeTypeInfo(A,B) _storeTypeInfo(A)
-static void _storeTypeInfo(Mem *pMem){
-  int flags = pMem->flags;
-  if( flags & MEM_Null ){
-    pMem->type = SQLITE_NULL;
-  }
-  else if( flags & MEM_Int ){
-    pMem->type = SQLITE_INTEGER;
-  }
-  else if( flags & MEM_Real ){
-    pMem->type = SQLITE_FLOAT;
-  }
-  else if( flags & MEM_Str ){
-    pMem->type = SQLITE_TEXT;
-  }else{
-    pMem->type = SQLITE_BLOB;
+static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
+  if( ALWAYS(pDef) && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
+    sqlite3DbFree(db, pDef);
   }
 }
 
 /*
-** Properties of opcodes.  The OPFLG_INITIALIZER macro is
-** created by mkopcodeh.awk during compilation.  Data is obtained
-** from the comments following the "case OP_xxxx:" statements in
-** this file.  
+** Delete a P4 value if necessary.
 */
-static unsigned char opcodeProperty[] = OPFLG_INITIALIZER;
+static void freeP4(sqlite3 *db, int p4type, void *p4){
+  if( p4 ){
+    switch( p4type ){
+      case P4_REAL:
+      case P4_INT64:
+      case P4_MPRINTF:
+      case P4_DYNAMIC:
+      case P4_KEYINFO:
+      case P4_INTARRAY:
+      case P4_KEYINFO_HANDOFF: {
+        sqlite3DbFree(db, p4);
+        break;
+      }
+      case P4_VDBEFUNC: {
+        VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
+        freeEphemeralFunction(db, pVdbeFunc->pFunc);
+        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
+        sqlite3DbFree(db, pVdbeFunc);
+        break;
+      }
+      case P4_FUNCDEF: {
+        freeEphemeralFunction(db, (FuncDef*)p4);
+        break;
+      }
+      case P4_MEM: {
+        sqlite3ValueFree((sqlite3_value*)p4);
+        break;
+      }
+      case P4_VTAB : {
+        sqlite3VtabUnlock((VTable *)p4);
+        break;
+      }
+      case P4_SUBPROGRAM : {
+        sqlite3VdbeProgramDelete(db, (SubProgram *)p4, 1);
+        break;
+      }
+    }
+  }
+}
 
 /*
-** Return true if an opcode has any of the OPFLG_xxx properties
-** specified by mask.
+** Free the space allocated for aOp and any p4 values allocated for the
+** opcodes contained within. If aOp is not NULL it is assumed to contain 
+** nOp entries. 
 */
-SQLITE_PRIVATE int sqlite3VdbeOpcodeHasProperty(int opcode, int mask){
-  assert( opcode>0 && opcode<sizeof(opcodeProperty) );
-  return (opcodeProperty[opcode]&mask)!=0;
+static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
+  if( aOp ){
+    Op *pOp;
+    for(pOp=aOp; pOp<&aOp[nOp]; pOp++){
+      freeP4(db, pOp->p4type, pOp->p4.p);
+#ifdef SQLITE_DEBUG
+      sqlite3DbFree(db, pOp->zComment);
+#endif     
+    }
+  }
+  sqlite3DbFree(db, aOp);
 }
 
 /*
-** Allocate cursor number iCur.  Return a pointer to it.  Return NULL
-** if we run out of memory.
+** Decrement the ref-count on the SubProgram structure passed as the
+** second argument. If the ref-count reaches zero, free the structure.
+**
+** The array of VDBE opcodes stored as SubProgram.aOp is freed if
+** either the ref-count reaches zero or parameter freeop is non-zero.
+**
+** Since the array of opcodes pointed to by SubProgram.aOp may directly
+** or indirectly contain a reference to the SubProgram structure itself.
+** By passing a non-zero freeop parameter, the caller may ensure that all
+** SubProgram structures and their aOp arrays are freed, even when there
+** are such circular references.
 */
-static Cursor *allocateCursor(
-  Vdbe *p, 
-  int iCur, 
-  Op *pOp,
-  int iDb, 
-  int isBtreeCursor
-){
-  /* Find the memory cell that will be used to store the blob of memory
-  ** required for this Cursor structure. It is convenient to use a 
-  ** vdbe memory cell to manage the memory allocation required for a
-  ** Cursor structure for the following reasons:
-  **
-  **   * Sometimes cursor numbers are used for a couple of different
-  **     purposes in a vdbe program. The different uses might require
-  **     different sized allocations. Memory cells provide growable
-  **     allocations.
-  **
-  **   * When using ENABLE_MEMORY_MANAGEMENT, memory cell buffers can
-  **     be freed lazily via the sqlite3_release_memory() API. This
-  **     minimizes the number of malloc calls made by the system.
-  **
-  ** Memory cells for cursors are allocated at the top of the address
-  ** space. Memory cell (p->nMem) corresponds to cursor 0. Space for
-  ** cursor 1 is managed by memory cell (p->nMem-1), etc.
-  */
-  Mem *pMem = &p->aMem[p->nMem-iCur];
-
-  int nByte;
-  Cursor *pCx = 0;
-  /* If the opcode of pOp is OP_SetNumColumns, then pOp->p2 contains
-  ** the number of fields in the records contained in the table or
-  ** index being opened. Use this to reserve space for the 
-  ** Cursor.aType[] array.
-  */
-  int nField = 0;
-  if( pOp->opcode==OP_SetNumColumns || pOp->opcode==OP_OpenEphemeral ){
-    nField = pOp->p2;
-  }
-  nByte = 
-      sizeof(Cursor) + 
-      (isBtreeCursor?sqlite3BtreeCursorSize():0) + 
-      2*nField*sizeof(u32);
-
-  assert( iCur<p->nCursor );
-  if( p->apCsr[iCur] ){
-    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
-    p->apCsr[iCur] = 0;
-  }
-  if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
-    p->apCsr[iCur] = pCx = (Cursor *)pMem->z;
-    memset(pMem->z, 0, nByte);
-    pCx->iDb = iDb;
-    pCx->nField = nField;
-    if( nField ){
-      pCx->aType = (u32 *)&pMem->z[sizeof(Cursor)];
+SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *db, SubProgram *p, int freeop){
+  if( p ){
+    assert( p->nRef>0 );
+    if( freeop || p->nRef==1 ){
+      Op *aOp = p->aOp;
+      p->aOp = 0;
+      vdbeFreeOpArray(db, aOp, p->nOp);
+      p->nOp = 0;
     }
-    if( isBtreeCursor ){
-      pCx->pCursor = (BtCursor *)&pMem->z[sizeof(Cursor)+2*nField*sizeof(u32)];
+    p->nRef--;
+    if( p->nRef==0 ){
+      sqlite3DbFree(db, p);
     }
   }
-  return pCx;
 }
 
+
 /*
-** Try to convert a value into a numeric representation if we can
-** do so without loss of information.  In other words, if the string
-** looks like a number, convert it into a number.  If it does not
-** look like a number, leave it alone.
+** Change N opcodes starting at addr to No-ops.
 */
-static void applyNumericAffinity(Mem *pRec){
-  if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
-    int realnum;
-    sqlite3VdbeMemNulTerminate(pRec);
-    if( (pRec->flags&MEM_Str)
-         && sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
-      i64 value;
-      sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
-      if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
-        pRec->u.i = value;
-        MemSetTypeFlag(pRec, MEM_Int);
-      }else{
-        sqlite3VdbeMemRealify(pRec);
-      }
+SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
+  if( p->aOp ){
+    VdbeOp *pOp = &p->aOp[addr];
+    sqlite3 *db = p->db;
+    while( N-- ){
+      freeP4(db, pOp->p4type, pOp->p4.p);
+      memset(pOp, 0, sizeof(pOp[0]));
+      pOp->opcode = OP_Noop;
+      pOp++;
     }
   }
 }
 
 /*
-** Processing is determine by the affinity parameter:
+** Change the value of the P4 operand for a specific instruction.
+** This routine is useful when a large program is loaded from a
+** static array using sqlite3VdbeAddOpList but we want to make a
+** few minor changes to the program.
 **
-** SQLITE_AFF_INTEGER:
-** SQLITE_AFF_REAL:
-** SQLITE_AFF_NUMERIC:
-**    Try to convert pRec to an integer representation or a 
-**    floating-point representation if an integer representation
-**    is not possible.  Note that the integer representation is
-**    always preferred, even if the affinity is REAL, because
-**    an integer representation is more space efficient on disk.
+** If n>=0 then the P4 operand is dynamic, meaning that a copy of
+** the string is made into memory obtained from sqlite3_malloc().
+** A value of n==0 means copy bytes of zP4 up to and including the
+** first null byte.  If n>0 then copy n+1 bytes of zP4.
 **
-** SQLITE_AFF_TEXT:
-**    Convert pRec to a text representation.
+** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
+** A copy is made of the KeyInfo structure into memory obtained from
+** sqlite3_malloc, to be freed when the Vdbe is finalized.
+** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
+** stored in memory that the caller has obtained from sqlite3_malloc. The 
+** caller should not free the allocation, it will be freed when the Vdbe is
+** finalized.
+** 
+** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
+** to a string or structure that is guaranteed to exist for the lifetime of
+** the Vdbe. In these cases we can just copy the pointer.
 **
-** SQLITE_AFF_NONE:
-**    No-op.  pRec is unchanged.
+** If addr<0 then change P4 on the most recently inserted instruction.
 */
-static void applyAffinity(
-  Mem *pRec,          /* The value to apply affinity to */
-  char affinity,      /* The affinity to be applied */
-  u8 enc              /* Use this text encoding */
-){
-  if( affinity==SQLITE_AFF_TEXT ){
-    /* Only attempt the conversion to TEXT if there is an integer or real
-    ** representation (blob and NULL do not get converted) but no string
-    ** representation.
-    */
-    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
-      sqlite3VdbeMemStringify(pRec, enc);
+SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
+  Op *pOp;
+  sqlite3 *db;
+  assert( p!=0 );
+  db = p->db;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  if( p->aOp==0 || db->mallocFailed ){
+    if ( n!=P4_KEYINFO && n!=P4_VTAB ) {
+      freeP4(db, n, (void*)*(char**)&zP4);
     }
-    pRec->flags &= ~(MEM_Real|MEM_Int);
-  }else if( affinity!=SQLITE_AFF_NONE ){
-    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
-             || affinity==SQLITE_AFF_NUMERIC );
-    applyNumericAffinity(pRec);
-    if( pRec->flags & MEM_Real ){
-      sqlite3VdbeIntegerAffinity(pRec);
+    return;
+  }
+  assert( p->nOp>0 );
+  assert( addr<p->nOp );
+  if( addr<0 ){
+    addr = p->nOp - 1;
+  }
+  pOp = &p->aOp[addr];
+  freeP4(db, pOp->p4type, pOp->p4.p);
+  pOp->p4.p = 0;
+  if( n==P4_INT32 ){
+    /* Note: this cast is safe, because the origin data point was an int
+    ** that was cast to a (const char *). */
+    pOp->p4.i = SQLITE_PTR_TO_INT(zP4);
+    pOp->p4type = P4_INT32;
+  }else if( zP4==0 ){
+    pOp->p4.p = 0;
+    pOp->p4type = P4_NOTUSED;
+  }else if( n==P4_KEYINFO ){
+    KeyInfo *pKeyInfo;
+    int nField, nByte;
+
+    nField = ((KeyInfo*)zP4)->nField;
+    nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
+    pKeyInfo = sqlite3Malloc( nByte );
+    pOp->p4.pKeyInfo = pKeyInfo;
+    if( pKeyInfo ){
+      u8 *aSortOrder;
+      memcpy(pKeyInfo, zP4, nByte);
+      aSortOrder = pKeyInfo->aSortOrder;
+      if( aSortOrder ){
+        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
+        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
+      }
+      pOp->p4type = P4_KEYINFO;
+    }else{
+      p->db->mallocFailed = 1;
+      pOp->p4type = P4_NOTUSED;
     }
+  }else if( n==P4_KEYINFO_HANDOFF ){
+    pOp->p4.p = (void*)zP4;
+    pOp->p4type = P4_KEYINFO;
+  }else if( n==P4_VTAB ){
+    pOp->p4.p = (void*)zP4;
+    pOp->p4type = P4_VTAB;
+    sqlite3VtabLock((VTable *)zP4);
+    assert( ((VTable *)zP4)->db==p->db );
+  }else if( n<0 ){
+    pOp->p4.p = (void*)zP4;
+    pOp->p4type = (signed char)n;
+  }else{
+    if( n==0 ) n = sqlite3Strlen30(zP4);
+    pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
+    pOp->p4type = P4_DYNAMIC;
   }
 }
 
+#ifndef NDEBUG
 /*
-** Try to convert the type of a function argument or a result column
-** into a numeric representation.  Use either INTEGER or REAL whichever
-** is appropriate.  But only do the conversion if it is possible without
-** loss of information and return the revised type of the argument.
-**
-** This is an EXPERIMENTAL api and is subject to change or removal.
+** Change the comment on the the most recently coded instruction.  Or
+** insert a No-op and add the comment to that new instruction.  This
+** makes the code easier to read during debugging.  None of this happens
+** in a production build.
 */
-SQLITE_API int sqlite3_value_numeric_type(sqlite3_value *pVal){
-  Mem *pMem = (Mem*)pVal;
-  applyNumericAffinity(pMem);
-  storeTypeInfo(pMem, 0);
-  return pMem->type;
+SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
+  va_list ap;
+  if( !p ) return;
+  assert( p->nOp>0 || p->aOp==0 );
+  assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
+  if( p->nOp ){
+    char **pz = &p->aOp[p->nOp-1].zComment;
+    va_start(ap, zFormat);
+    sqlite3DbFree(p->db, *pz);
+    *pz = sqlite3VMPrintf(p->db, zFormat, ap);
+    va_end(ap);
+  }
+}
+SQLITE_PRIVATE void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){
+  va_list ap;
+  if( !p ) return;
+  sqlite3VdbeAddOp0(p, OP_Noop);
+  assert( p->nOp>0 || p->aOp==0 );
+  assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
+  if( p->nOp ){
+    char **pz = &p->aOp[p->nOp-1].zComment;
+    va_start(ap, zFormat);
+    sqlite3DbFree(p->db, *pz);
+    *pz = sqlite3VMPrintf(p->db, zFormat, ap);
+    va_end(ap);
+  }
 }
+#endif  /* NDEBUG */
 
 /*
-** Exported version of applyAffinity(). This one works on sqlite3_value*, 
-** not the internal Mem* type.
+** Return the opcode for a given address.  If the address is -1, then
+** return the most recently inserted opcode.
+**
+** If a memory allocation error has occurred prior to the calling of this
+** routine, then a pointer to a dummy VdbeOp will be returned.  That opcode
+** is readable and writable, but it has no effect.  The return of a dummy
+** opcode allows the call to continue functioning after a OOM fault without
+** having to check to see if the return from this routine is a valid pointer.
+**
+** About the #ifdef SQLITE_OMIT_TRACE:  Normally, this routine is never called
+** unless p->nOp>0.  This is because in the absense of SQLITE_OMIT_TRACE,
+** an OP_Trace instruction is always inserted by sqlite3VdbeGet() as soon as
+** a new VDBE is created.  So we are free to set addr to p->nOp-1 without
+** having to double-check to make sure that the result is non-negative. But
+** if SQLITE_OMIT_TRACE is defined, the OP_Trace is omitted and we do need to
+** check the value of p->nOp-1 before continuing.
 */
-SQLITE_PRIVATE void sqlite3ValueApplyAffinity(
-  sqlite3_value *pVal, 
-  u8 affinity, 
-  u8 enc
-){
-  applyAffinity((Mem *)pVal, affinity, enc);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
+  static VdbeOp dummy;
+  assert( p->magic==VDBE_MAGIC_INIT );
+  if( addr<0 ){
+#ifdef SQLITE_OMIT_TRACE
+    if( p->nOp==0 ) return &dummy;
+#endif
+    addr = p->nOp - 1;
+  }
+  assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
+  if( p->db->mallocFailed ){
+    return &dummy;
+  }else{
+    return &p->aOp[addr];
+  }
 }
 
-#ifdef SQLITE_DEBUG
+#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
+     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
 /*
-** Write a nice string representation of the contents of cell pMem
-** into buffer zBuf, length nBuf.
+** Compute a string that describes the P4 parameter for an opcode.
+** Use zTemp for any required temporary buffer space.
 */
-SQLITE_PRIVATE void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf){
-  char *zCsr = zBuf;
-  int f = pMem->flags;
-
-  static const char *const encnames[] = {"(X)", "(8)", "(16LE)", "(16BE)"};
-
-  if( f&MEM_Blob ){
-    int i;
-    char c;
-    if( f & MEM_Dyn ){
-      c = 'z';
-      assert( (f & (MEM_Static|MEM_Ephem))==0 );
-    }else if( f & MEM_Static ){
-      c = 't';
-      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
-    }else if( f & MEM_Ephem ){
-      c = 'e';
-      assert( (f & (MEM_Static|MEM_Dyn))==0 );
-    }else{
-      c = 's';
+static char *displayP4(Op *pOp, char *zTemp, int nTemp){
+  char *zP4 = zTemp;
+  assert( nTemp>=20 );
+  switch( pOp->p4type ){
+    case P4_KEYINFO_STATIC:
+    case P4_KEYINFO: {
+      int i, j;
+      KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
+      sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
+      i = sqlite3Strlen30(zTemp);
+      for(j=0; j<pKeyInfo->nField; j++){
+        CollSeq *pColl = pKeyInfo->aColl[j];
+        if( pColl ){
+          int n = sqlite3Strlen30(pColl->zName);
+          if( i+n>nTemp-6 ){
+            memcpy(&zTemp[i],",...",4);
+            break;
+          }
+          zTemp[i++] = ',';
+          if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
+            zTemp[i++] = '-';
+          }
+          memcpy(&zTemp[i], pColl->zName,n+1);
+          i += n;
+        }else if( i+4<nTemp-6 ){
+          memcpy(&zTemp[i],",nil",4);
+          i += 4;
+        }
+      }
+      zTemp[i++] = ')';
+      zTemp[i] = 0;
+      assert( i<nTemp );
+      break;
     }
-
-    sqlite3_snprintf(100, zCsr, "%c", c);
-    zCsr += strlen(zCsr);
-    sqlite3_snprintf(100, zCsr, "%d[", pMem->n);
-    zCsr += strlen(zCsr);
-    for(i=0; i<16 && i<pMem->n; i++){
-      sqlite3_snprintf(100, zCsr, "%02X", ((int)pMem->z[i] & 0xFF));
-      zCsr += strlen(zCsr);
+    case P4_COLLSEQ: {
+      CollSeq *pColl = pOp->p4.pColl;
+      sqlite3_snprintf(nTemp, zTemp, "collseq(%.20s)", pColl->zName);
+      break;
     }
-    for(i=0; i<16 && i<pMem->n; i++){
-      char z = pMem->z[i];
-      if( z<32 || z>126 ) *zCsr++ = '.';
-      else *zCsr++ = z;
+    case P4_FUNCDEF: {
+      FuncDef *pDef = pOp->p4.pFunc;
+      sqlite3_snprintf(nTemp, zTemp, "%s(%d)", pDef->zName, pDef->nArg);
+      break;
     }
-
-    sqlite3_snprintf(100, zCsr, "]%s", encnames[pMem->enc]);
-    zCsr += strlen(zCsr);
-    if( f & MEM_Zero ){
-      sqlite3_snprintf(100, zCsr,"+%lldz",pMem->u.i);
-      zCsr += strlen(zCsr);
+    case P4_INT64: {
+      sqlite3_snprintf(nTemp, zTemp, "%lld", *pOp->p4.pI64);
+      break;
     }
-    *zCsr = '\0';
-  }else if( f & MEM_Str ){
-    int j, k;
-    zBuf[0] = ' ';
-    if( f & MEM_Dyn ){
-      zBuf[1] = 'z';
-      assert( (f & (MEM_Static|MEM_Ephem))==0 );
-    }else if( f & MEM_Static ){
-      zBuf[1] = 't';
-      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
-    }else if( f & MEM_Ephem ){
-      zBuf[1] = 'e';
-      assert( (f & (MEM_Static|MEM_Dyn))==0 );
-    }else{
-      zBuf[1] = 's';
+    case P4_INT32: {
+      sqlite3_snprintf(nTemp, zTemp, "%d", pOp->p4.i);
+      break;
     }
-    k = 2;
-    sqlite3_snprintf(100, &zBuf[k], "%d", pMem->n);
-    k += strlen(&zBuf[k]);
-    zBuf[k++] = '[';
-    for(j=0; j<15 && j<pMem->n; j++){
-      u8 c = pMem->z[j];
-      if( c>=0x20 && c<0x7f ){
-        zBuf[k++] = c;
+    case P4_REAL: {
+      sqlite3_snprintf(nTemp, zTemp, "%.16g", *pOp->p4.pReal);
+      break;
+    }
+    case P4_MEM: {
+      Mem *pMem = pOp->p4.pMem;
+      assert( (pMem->flags & MEM_Null)==0 );
+      if( pMem->flags & MEM_Str ){
+        zP4 = pMem->z;
+      }else if( pMem->flags & MEM_Int ){
+        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
+      }else if( pMem->flags & MEM_Real ){
+        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
       }else{
-        zBuf[k++] = '.';
+        assert( pMem->flags & MEM_Blob );
+        zP4 = "(blob)";
+      }
+      break;
+    }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    case P4_VTAB: {
+      sqlite3_vtab *pVtab = pOp->p4.pVtab->pVtab;
+      sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
+      break;
+    }
+#endif
+    case P4_INTARRAY: {
+      sqlite3_snprintf(nTemp, zTemp, "intarray");
+      break;
+    }
+    case P4_SUBPROGRAM: {
+      sqlite3_snprintf(nTemp, zTemp, "program");
+      break;
+    }
+    default: {
+      zP4 = pOp->p4.z;
+      if( zP4==0 ){
+        zP4 = zTemp;
+        zTemp[0] = 0;
       }
     }
-    zBuf[k++] = ']';
-    sqlite3_snprintf(100,&zBuf[k], encnames[pMem->enc]);
-    k += strlen(&zBuf[k]);
-    zBuf[k++] = 0;
   }
+  assert( zP4!=0 );
+  return zP4;
 }
 #endif
 
-#ifdef SQLITE_DEBUG
 /*
-** Print the value of a register for tracing purposes:
+** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
 */
-static void memTracePrint(FILE *out, Mem *p){
-  if( p->flags & MEM_Null ){
-    fprintf(out, " NULL");
-  }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
-    fprintf(out, " si:%lld", p->u.i);
-  }else if( p->flags & MEM_Int ){
-    fprintf(out, " i:%lld", p->u.i);
-  }else if( p->flags & MEM_Real ){
-    fprintf(out, " r:%g", p->r);
-  }else{
-    char zBuf[200];
-    sqlite3VdbeMemPrettyPrint(p, zBuf);
-    fprintf(out, " ");
-    fprintf(out, "%s", zBuf);
+SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe *p, int i){
+  int mask;
+  assert( i>=0 && i<p->db->nDb && i<sizeof(u32)*8 );
+  assert( i<(int)sizeof(p->btreeMask)*8 );
+  mask = ((u32)1)<<i;
+  if( (p->btreeMask & mask)==0 ){
+    p->btreeMask |= mask;
+    sqlite3BtreeMutexArrayInsert(&p->aMutex, p->db->aDb[i].pBt);
   }
 }
-static void registerTrace(FILE *out, int iReg, Mem *p){
-  fprintf(out, "REG[%d] = ", iReg);
-  memTracePrint(out, p);
-  fprintf(out, "\n");
-}
-#endif
-
-#ifdef SQLITE_DEBUG
-#  define REGISTER_TRACE(R,M) if(p->trace&&R>0)registerTrace(p->trace,R,M)
-#else
-#  define REGISTER_TRACE(R,M)
-#endif
 
 
-#ifdef VDBE_PROFILE
+#if defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
 /*
-** The following routine only works on pentium-class processors.
-** It uses the RDTSC opcode to read the cycle count value out of the
-** processor and returns that value.  This can be used for high-res
-** profiling.
+** Print a single opcode.  This routine is used for debugging only.
 */
-__inline__ unsigned long long int hwtime(void){
-   unsigned int lo, hi;
-   /* We cannot use "=A", since this would use %rax on x86_64 */
-   __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
-   return (unsigned long long int)hi << 32 | lo;
+SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
+  char *zP4;
+  char zPtr[50];
+  static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
+  if( pOut==0 ) pOut = stdout;
+  zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
+  fprintf(pOut, zFormat1, pc, 
+      sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
+#ifdef SQLITE_DEBUG
+      pOp->zComment ? pOp->zComment : ""
+#else
+      ""
+#endif
+  );
+  fflush(pOut);
 }
 #endif
 
 /*
-** The CHECK_FOR_INTERRUPT macro defined here looks to see if the
-** sqlite3_interrupt() routine has been called.  If it has been, then
-** processing of the VDBE program is interrupted.
-**
-** This macro added to every instruction that does a jump in order to
-** implement a loop.  This test used to be on every single instruction,
-** but that meant we more testing that we needed.  By only testing the
-** flag on jump instructions, we get a (small) speed improvement.
+** Release an array of N Mem elements
 */
-#define CHECK_FOR_INTERRUPT \
-   if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
+static void releaseMemArray(Mem *p, int N){
+  if( p && N ){
+    Mem *pEnd;
+    sqlite3 *db = p->db;
+    u8 malloc_failed = db->mallocFailed;
+    for(pEnd=&p[N]; p<pEnd; p++){
+      assert( (&p[1])==pEnd || p[0].db==p[1].db );
+
+      /* This block is really an inlined version of sqlite3VdbeMemRelease()
+      ** that takes advantage of the fact that the memory cell value is 
+      ** being set to NULL after releasing any dynamic resources.
+      **
+      ** The justification for duplicating code is that according to 
+      ** callgrind, this causes a certain test case to hit the CPU 4.7 
+      ** percent less (x86 linux, gcc version 4.1.2, -O6) than if 
+      ** sqlite3MemRelease() were called from here. With -O2, this jumps
+      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
+      ** with no indexes using a single prepared INSERT statement, bind() 
+      ** and reset(). Inserts are grouped into a transaction.
+      */
+      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
+        sqlite3VdbeMemRelease(p);
+      }else if( p->zMalloc ){
+        sqlite3DbFree(db, p->zMalloc);
+        p->zMalloc = 0;
+      }
 
+      p->flags = MEM_Null;
+    }
+    db->mallocFailed = malloc_failed;
+  }
+}
 
 /*
-** Execute as much of a VDBE program as we can then return.
-**
-** sqlite3VdbeMakeReady() must be called before this routine in order to
-** close the program with a final OP_Halt and to set up the callbacks
-** and the error message pointer.
-**
-** Whenever a row or result data is available, this routine will either
-** invoke the result callback (if there is one) or return with
-** SQLITE_ROW.
-**
-** If an attempt is made to open a locked database, then this routine
-** will either invoke the busy callback (if there is one) or it will
-** return SQLITE_BUSY.
-**
-** If an error occurs, an error message is written to memory obtained
-** from sqlite3_malloc() and p->zErrMsg is made to point to that memory.
-** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
-**
-** If the callback ever returns non-zero, then the program exits
-** immediately.  There will be no error message but the p->rc field is
-** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
-**
-** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
-** routine to return SQLITE_ERROR.
+** Delete a VdbeFrame object and its contents. VdbeFrame objects are
+** allocated by the OP_Program opcode in sqlite3VdbeExec().
+*/
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame *p){
+  int i;
+  Mem *aMem = VdbeFrameMem(p);
+  VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
+  for(i=0; i<p->nChildCsr; i++){
+    sqlite3VdbeFreeCursor(p->v, apCsr[i]);
+  }
+  releaseMemArray(aMem, p->nChildMem);
+  sqlite3DbFree(p->v->db, p);
+}
+
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+SQLITE_PRIVATE int sqlite3VdbeReleaseBuffers(Vdbe *p){
+  int ii;
+  int nFree = 0;
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  for(ii=1; ii<=p->nMem; ii++){
+    Mem *pMem = &p->aMem[ii];
+    if( pMem->flags & MEM_RowSet ){
+      sqlite3RowSetClear(pMem->u.pRowSet);
+    }
+    if( pMem->z && pMem->flags&MEM_Dyn ){
+      assert( !pMem->xDel );
+      nFree += sqlite3DbMallocSize(pMem->db, pMem->z);
+      sqlite3VdbeMemRelease(pMem);
+    }
+  }
+  return nFree;
+}
+#endif
+
+#ifndef SQLITE_OMIT_EXPLAIN
+/*
+** Give a listing of the program in the virtual machine.
 **
-** Other fatal errors return SQLITE_ERROR.
+** The interface is the same as sqlite3VdbeExec().  But instead of
+** running the code, it invokes the callback once for each instruction.
+** This feature is used to implement "EXPLAIN".
 **
-** After this routine has finished, sqlite3VdbeFinalize() should be
-** used to clean up the mess that was left behind.
+** When p->explain==1, each instruction is listed.  When
+** p->explain==2, only OP_Explain instructions are listed and these
+** are shown in a different format.  p->explain==2 is used to implement
+** EXPLAIN QUERY PLAN.
 */
-SQLITE_PRIVATE int sqlite3VdbeExec(
-  Vdbe *p                    /* The VDBE */
+SQLITE_PRIVATE int sqlite3VdbeList(
+  Vdbe *p                   /* The VDBE */
 ){
-  int pc;                    /* The program counter */
-  Op *pOp;                   /* Current operation */
-  int rc = SQLITE_OK;        /* Value to return */
-  sqlite3 *db = p->db;       /* The database */
-  u8 encoding = ENC(db);     /* The database encoding */
-  Mem *pIn1, *pIn2, *pIn3;   /* Input operands */
-  Mem *pOut;                 /* Output operand */
-  u8 opProperty;
-#ifdef VDBE_PROFILE
-  unsigned long long start;  /* CPU clock count at start of opcode */
-  int origPc;                /* Program counter at start of opcode */
-#endif
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
-#endif
+  int nRow;                            /* Total number of rows to return */
+  int nSub = 0;                        /* Number of sub-vdbes seen so far */
+  SubProgram **apSub = 0;              /* Array of sub-vdbes */
+  Mem *pSub = 0;
+  sqlite3 *db = p->db;
+  int i;
+  int rc = SQLITE_OK;
+  Mem *pMem = p->pResultSet = &p->aMem[1];
 
-  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
+  assert( p->explain );
+  assert( p->magic==VDBE_MAGIC_RUN );
   assert( db->magic==SQLITE_MAGIC_BUSY );
-  sqlite3BtreeMutexArrayEnter(&p->aMutex);
+  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY || p->rc==SQLITE_NOMEM );
+
+  /* Even though this opcode does not use dynamic strings for
+  ** the result, result columns may become dynamic if the user calls
+  ** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
+  */
+  releaseMemArray(pMem, 8);
+
   if( p->rc==SQLITE_NOMEM ){
     /* This happens if a malloc() inside a call to sqlite3_column_text() or
     ** sqlite3_column_text16() failed.  */
-    goto no_mem;
-  }
-  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
-  p->rc = SQLITE_OK;
-  assert( p->explain==0 );
-  p->pResultSet = 0;
-  db->busyHandler.nBusy = 0;
-  CHECK_FOR_INTERRUPT;
-  sqlite3VdbeIOTraceSql(p);
-#ifdef SQLITE_DEBUG
-  sqlite3FaultBeginBenign(-1);
-  if( p->pc==0 && ((p->db->flags & SQLITE_VdbeListing)!=0
-    || sqlite3OsAccess(db->pVfs, "vdbe_explain", SQLITE_ACCESS_EXISTS)==1 )
-  ){
-    int i;
-    printf("VDBE Program Listing:\n");
-    sqlite3VdbePrintSql(p);
-    for(i=0; i<p->nOp; i++){
-      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
-    }
-  }
-  if( sqlite3OsAccess(db->pVfs, "vdbe_trace", SQLITE_ACCESS_EXISTS)==1 ){
-    p->trace = stdout;
+    db->mallocFailed = 1;
+    return SQLITE_ERROR;
   }
-  sqlite3FaultEndBenign(-1);
-#endif
-  for(pc=p->pc; rc==SQLITE_OK; pc++){
-    assert( pc>=0 && pc<p->nOp );
-    if( db->mallocFailed ) goto no_mem;
-#ifdef VDBE_PROFILE
-    origPc = pc;
-    start = hwtime();
-#endif
-    pOp = &p->aOp[pc];
 
-    /* Only allow tracing if SQLITE_DEBUG is defined.
-    */
-#ifdef SQLITE_DEBUG
-    if( p->trace ){
-      if( pc==0 ){
-        printf("VDBE Execution Trace:\n");
-        sqlite3VdbePrintSql(p);
-      }
-      sqlite3VdbePrintOp(p->trace, pc, pOp);
+  /* Figure out total number of rows that will be returned by this 
+  ** EXPLAIN program.  */
+  nRow = p->nOp;
+  if( p->explain==1 ){
+    pSub = &p->aMem[9];
+    if( pSub->flags&MEM_Blob ){
+      nSub = pSub->n/sizeof(Vdbe*);
+      apSub = (SubProgram **)pSub->z;
     }
-    if( p->trace==0 && pc==0 ){
-      sqlite3FaultBeginBenign(-1);
-      if( sqlite3OsAccess(db->pVfs, "vdbe_sqltrace", SQLITE_ACCESS_EXISTS)==1 ){
-        sqlite3VdbePrintSql(p);
-      }
-      sqlite3FaultEndBenign(-1);
+    for(i=0; i<nSub; i++){
+      nRow += apSub[i]->nOp;
     }
-#endif
-      
+  }
 
-    /* Check to see if we need to simulate an interrupt.  This only happens
-    ** if we have a special test build.
-    */
-#ifdef SQLITE_TEST
-    if( sqlite3_interrupt_count>0 ){
-      sqlite3_interrupt_count--;
-      if( sqlite3_interrupt_count==0 ){
-        sqlite3_interrupt(db);
+  do{
+    i = p->pc++;
+  }while( i<nRow && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
+  if( i>=nRow ){
+    p->rc = SQLITE_OK;
+    rc = SQLITE_DONE;
+  }else if( db->u1.isInterrupted ){
+    p->rc = SQLITE_INTERRUPT;
+    rc = SQLITE_ERROR;
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(p->rc));
+  }else{
+    char *z;
+    Op *pOp;
+    if( i<p->nOp ){
+      pOp = &p->aOp[i];
+    }else{
+      int j;
+      i -= p->nOp;
+      for(j=0; i>=apSub[j]->nOp; j++){
+        i -= apSub[j]->nOp;
       }
+      pOp = &apSub[j]->aOp[i];
     }
-#endif
+    if( p->explain==1 ){
+      pMem->flags = MEM_Int;
+      pMem->type = SQLITE_INTEGER;
+      pMem->u.i = i;                                /* Program counter */
+      pMem++;
+  
+      pMem->flags = MEM_Static|MEM_Str|MEM_Term;
+      pMem->z = (char*)sqlite3OpcodeName(pOp->opcode);  /* Opcode */
+      assert( pMem->z!=0 );
+      pMem->n = sqlite3Strlen30(pMem->z);
+      pMem->type = SQLITE_TEXT;
+      pMem->enc = SQLITE_UTF8;
+      pMem++;
 
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-    /* Call the progress callback if it is configured and the required number
-    ** of VDBE ops have been executed (either since this invocation of
-    ** sqlite3VdbeExec() or since last time the progress callback was called).
-    ** If the progress callback returns non-zero, exit the virtual machine with
-    ** a return code SQLITE_ABORT.
-    */
-    if( db->xProgress ){
-      if( db->nProgressOps==nProgressOps ){
-        int prc;
-        if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-        prc =db->xProgress(db->pProgressArg);
-        if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-        if( prc!=0 ){
-          rc = SQLITE_INTERRUPT;
-          goto vdbe_error_halt;
+      if( pOp->p4type==P4_SUBPROGRAM ){
+        int nByte = (nSub+1)*sizeof(SubProgram*);
+        int j;
+        for(j=0; j<nSub; j++){
+          if( apSub[j]==pOp->p4.pProgram ) break;
+        }
+        if( j==nSub && SQLITE_OK==sqlite3VdbeMemGrow(pSub, nByte, 1) ){
+          apSub = (SubProgram **)pSub->z;
+          apSub[nSub++] = pOp->p4.pProgram;
+          pSub->flags |= MEM_Blob;
+          pSub->n = nSub*sizeof(SubProgram*);
         }
-        nProgressOps = 0;
       }
-      nProgressOps++;
     }
-#endif
 
-    /* Do common setup processing for any opcode that is marked
-    ** with the "out2-prerelease" tag.  Such opcodes have a single
-    ** output which is specified by the P2 parameter.  The P2 register
-    ** is initialized to a NULL.
-    */
-    opProperty = opcodeProperty[pOp->opcode];
-    if( (opProperty & OPFLG_OUT2_PRERELEASE)!=0 ){
-      assert( pOp->p2>0 );
-      assert( pOp->p2<=p->nMem );
-      pOut = &p->aMem[pOp->p2];
-      sqlite3VdbeMemReleaseExternal(pOut);
-      pOut->flags = MEM_Null;
-    }else
- 
-    /* Do common setup for opcodes marked with one of the following
-    ** combinations of properties.
-    **
-    **           in1
-    **           in1 in2
-    **           in1 in2 out3
-    **           in1 in3
-    **
-    ** Variables pIn1, pIn2, and pIn3 are made to point to appropriate
-    ** registers for inputs.  Variable pOut points to the output register.
-    */
-    if( (opProperty & OPFLG_IN1)!=0 ){
-      assert( pOp->p1>0 );
-      assert( pOp->p1<=p->nMem );
-      pIn1 = &p->aMem[pOp->p1];
-      REGISTER_TRACE(pOp->p1, pIn1);
-      if( (opProperty & OPFLG_IN2)!=0 ){
-        assert( pOp->p2>0 );
-        assert( pOp->p2<=p->nMem );
-        pIn2 = &p->aMem[pOp->p2];
-        REGISTER_TRACE(pOp->p2, pIn2);
-        if( (opProperty & OPFLG_OUT3)!=0 ){
-          assert( pOp->p3>0 );
-          assert( pOp->p3<=p->nMem );
-          pOut = &p->aMem[pOp->p3];
-        }
-      }else if( (opProperty & OPFLG_IN3)!=0 ){
-        assert( pOp->p3>0 );
-        assert( pOp->p3<=p->nMem );
-        pIn3 = &p->aMem[pOp->p3];
-        REGISTER_TRACE(pOp->p3, pIn3);
-      }
-    }else if( (opProperty & OPFLG_IN2)!=0 ){
-      assert( pOp->p2>0 );
-      assert( pOp->p2<=p->nMem );
-      pIn2 = &p->aMem[pOp->p2];
-      REGISTER_TRACE(pOp->p2, pIn2);
-    }else if( (opProperty & OPFLG_IN3)!=0 ){
-      assert( pOp->p3>0 );
-      assert( pOp->p3<=p->nMem );
-      pIn3 = &p->aMem[pOp->p3];
-      REGISTER_TRACE(pOp->p3, pIn3);
+    pMem->flags = MEM_Int;
+    pMem->u.i = pOp->p1;                          /* P1 */
+    pMem->type = SQLITE_INTEGER;
+    pMem++;
+
+    pMem->flags = MEM_Int;
+    pMem->u.i = pOp->p2;                          /* P2 */
+    pMem->type = SQLITE_INTEGER;
+    pMem++;
+
+    if( p->explain==1 ){
+      pMem->flags = MEM_Int;
+      pMem->u.i = pOp->p3;                          /* P3 */
+      pMem->type = SQLITE_INTEGER;
+      pMem++;
     }
 
-    switch( pOp->opcode ){
+    if( sqlite3VdbeMemGrow(pMem, 32, 0) ){            /* P4 */
+      assert( p->db->mallocFailed );
+      return SQLITE_ERROR;
+    }
+    pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
+    z = displayP4(pOp, pMem->z, 32);
+    if( z!=pMem->z ){
+      sqlite3VdbeMemSetStr(pMem, z, -1, SQLITE_UTF8, 0);
+    }else{
+      assert( pMem->z!=0 );
+      pMem->n = sqlite3Strlen30(pMem->z);
+      pMem->enc = SQLITE_UTF8;
+    }
+    pMem->type = SQLITE_TEXT;
+    pMem++;
 
-/*****************************************************************************
-** What follows is a massive switch statement where each case implements a
-** separate instruction in the virtual machine.  If we follow the usual
-** indentation conventions, each case should be indented by 6 spaces.  But
-** that is a lot of wasted space on the left margin.  So the code within
-** the switch statement will break with convention and be flush-left. Another
-** big comment (similar to this one) will mark the point in the code where
-** we transition back to normal indentation.
-**
-** The formatting of each case is important.  The makefile for SQLite
-** generates two C files "opcodes.h" and "opcodes.c" by scanning this
-** file looking for lines that begin with "case OP_".  The opcodes.h files
-** will be filled with #defines that give unique integer values to each
-** opcode and the opcodes.c file is filled with an array of strings where
-** each string is the symbolic name for the corresponding opcode.  If the
-** case statement is followed by a comment of the form "/# same as ... #/"
-** that comment is used to determine the particular value of the opcode.
-**
-** Other keywords in the comment that follows each case are used to
-** construct the OPFLG_INITIALIZER value that initializes opcodeProperty[].
-** Keywords include: in1, in2, in3, out2_prerelease, out2, out3.  See
-** the mkopcodeh.awk script for additional information.
-**
-** Documentation about VDBE opcodes is generated by scanning this file
-** for lines of that contain "Opcode:".  That line and all subsequent
-** comment lines are used in the generation of the opcode.html documentation
-** file.
-**
-** SUMMARY:
-**
-**     Formatting is important to scripts that scan this file.
-**     Do not deviate from the formatting style currently in use.
-**
-*****************************************************************************/
+    if( p->explain==1 ){
+      if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
+        assert( p->db->mallocFailed );
+        return SQLITE_ERROR;
+      }
+      pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
+      pMem->n = 2;
+      sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5);   /* P5 */
+      pMem->type = SQLITE_TEXT;
+      pMem->enc = SQLITE_UTF8;
+      pMem++;
+  
+#ifdef SQLITE_DEBUG
+      if( pOp->zComment ){
+        pMem->flags = MEM_Str|MEM_Term;
+        pMem->z = pOp->zComment;
+        pMem->n = sqlite3Strlen30(pMem->z);
+        pMem->enc = SQLITE_UTF8;
+        pMem->type = SQLITE_TEXT;
+      }else
+#endif
+      {
+        pMem->flags = MEM_Null;                       /* Comment */
+        pMem->type = SQLITE_NULL;
+      }
+    }
 
-/* Opcode:  Goto * P2 * * *
-**
-** An unconditional jump to address P2.
-** The next instruction executed will be 
-** the one at index P2 from the beginning of
-** the program.
-*/
-case OP_Goto: {             /* jump */
-  CHECK_FOR_INTERRUPT;
-  pc = pOp->p2 - 1;
-  break;
+    p->nResColumn = 8 - 5*(p->explain-1);
+    p->rc = SQLITE_OK;
+    rc = SQLITE_ROW;
+  }
+  return rc;
 }
+#endif /* SQLITE_OMIT_EXPLAIN */
 
-/* Opcode:  Gosub * P2 * * *
-**
-** Push the current address plus 1 onto the return address stack
-** and then jump to address P2.
-**
-** The return address stack is of limited depth.  If too many
-** OP_Gosub operations occur without intervening OP_Returns, then
-** the return address stack will fill up and processing will abort
-** with a fatal error.
+#ifdef SQLITE_DEBUG
+/*
+** Print the SQL that was used to generate a VDBE program.
 */
-case OP_Gosub: {            /* jump */
-  assert( p->returnDepth<sizeof(p->returnStack)/sizeof(p->returnStack[0]) );
-  p->returnStack[p->returnDepth++] = pc+1;
-  pc = pOp->p2 - 1;
-  break;
+SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe *p){
+  int nOp = p->nOp;
+  VdbeOp *pOp;
+  if( nOp<1 ) return;
+  pOp = &p->aOp[0];
+  if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
+    const char *z = pOp->p4.z;
+    while( sqlite3Isspace(*z) ) z++;
+    printf("SQL: [%s]\n", z);
+  }
 }
+#endif
 
-/* Opcode:  Return * * * * *
-**
-** Jump immediately to the next instruction after the last unreturned
-** OP_Gosub.  If an OP_Return has occurred for all OP_Gosubs, then
-** processing aborts with a fatal error.
+#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
+/*
+** Print an IOTRACE message showing SQL content.
 */
-case OP_Return: {
-  assert( p->returnDepth>0 );
-  p->returnDepth--;
-  pc = p->returnStack[p->returnDepth] - 1;
-  break;
+SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
+  int nOp = p->nOp;
+  VdbeOp *pOp;
+  if( sqlite3IoTrace==0 ) return;
+  if( nOp<1 ) return;
+  pOp = &p->aOp[0];
+  if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
+    int i, j;
+    char z[1000];
+    sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
+    for(i=0; sqlite3Isspace(z[i]); i++){}
+    for(j=0; z[i]; i++){
+      if( sqlite3Isspace(z[i]) ){
+        if( z[i-1]!=' ' ){
+          z[j++] = ' ';
+        }
+      }else{
+        z[j++] = z[i];
+      }
+    }
+    z[j] = 0;
+    sqlite3IoTrace("SQL %s\n", z);
+  }
 }
+#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
 
-/* Opcode:  Halt P1 P2 * P4 *
-**
-** Exit immediately.  All open cursors, Fifos, etc are closed
-** automatically.
+/*
+** Allocate space from a fixed size buffer.  Make *pp point to the
+** allocated space.  (Note:  pp is a char* rather than a void** to
+** work around the pointer aliasing rules of C.)  *pp should initially
+** be zero.  If *pp is not zero, that means that the space has already
+** been allocated and this routine is a noop.
 **
-** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
-** or sqlite3_finalize().  For a normal halt, this should be SQLITE_OK (0).
-** For errors, it can be some other value.  If P1!=0 then P2 will determine
-** whether or not to rollback the current transaction.  Do not rollback
-** if P2==OE_Fail. Do the rollback if P2==OE_Rollback.  If P2==OE_Abort,
-** then back out all changes that have occurred during this execution of the
-** VDBE, but do not rollback the transaction. 
+** nByte is the number of bytes of space needed.
 **
-** If P4 is not null then it is an error message string.
+** *ppFrom point to available space and pEnd points to the end of the
+** available space.
 **
-** There is an implied "Halt 0 0 0" instruction inserted at the very end of
-** every program.  So a jump past the last instruction of the program
-** is the same as executing Halt.
+** *pnByte is a counter of the number of bytes of space that have failed
+** to allocate.  If there is insufficient space in *ppFrom to satisfy the
+** request, then increment *pnByte by the amount of the request.
 */
-case OP_Halt: {
-  p->rc = pOp->p1;
-  p->pc = pc;
-  p->errorAction = pOp->p2;
-  if( pOp->p4.z ){
-    sqlite3SetString(&p->zErrMsg, pOp->p4.z, (char*)0);
-  }
-  rc = sqlite3VdbeHalt(p);
-  assert( rc==SQLITE_BUSY || rc==SQLITE_OK );
-  if( rc==SQLITE_BUSY ){
-    p->rc = rc = SQLITE_BUSY;
-  }else{
-    rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
+static void allocSpace(
+  char *pp,            /* IN/OUT: Set *pp to point to allocated buffer */
+  int nByte,           /* Number of bytes to allocate */
+  u8 **ppFrom,         /* IN/OUT: Allocate from *ppFrom */
+  u8 *pEnd,            /* Pointer to 1 byte past the end of *ppFrom buffer */
+  int *pnByte          /* If allocation cannot be made, increment *pnByte */
+){
+  assert( EIGHT_BYTE_ALIGNMENT(*ppFrom) );
+  if( (*(void**)pp)==0 ){
+    nByte = ROUND8(nByte);
+    if( &(*ppFrom)[nByte] <= pEnd ){
+      *(void**)pp = (void *)*ppFrom;
+      *ppFrom += nByte;
+    }else{
+      *pnByte += nByte;
+    }
   }
-  goto vdbe_return;
 }
 
-/* Opcode: Integer P1 P2 * * *
+/*
+** Prepare a virtual machine for execution.  This involves things such
+** as allocating stack space and initializing the program counter.
+** After the VDBE has be prepped, it can be executed by one or more
+** calls to sqlite3VdbeExec().  
 **
-** The 32-bit integer value P1 is written into register P2.
-*/
-case OP_Integer: {         /* out2-prerelease */
-  pOut->flags = MEM_Int;
-  pOut->u.i = pOp->p1;
-  break;
-}
-
-/* Opcode: Int64 * P2 * P4 *
+** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
+** VDBE_MAGIC_RUN.
 **
-** P4 is a pointer to a 64-bit integer value.
-** Write that value into register P2.
+** This function may be called more than once on a single virtual machine.
+** The first call is made while compiling the SQL statement. Subsequent
+** calls are made as part of the process of resetting a statement to be
+** re-executed (from a call to sqlite3_reset()). The nVar, nMem, nCursor 
+** and isExplain parameters are only passed correct values the first time
+** the function is called. On subsequent calls, from sqlite3_reset(), nVar
+** is passed -1 and nMem, nCursor and isExplain are all passed zero.
 */
-case OP_Int64: {           /* out2-prerelease */
-  assert( pOp->p4.pI64!=0 );
-  pOut->flags = MEM_Int;
-  pOut->u.i = *pOp->p4.pI64;
-  break;
-}
+SQLITE_PRIVATE void sqlite3VdbeMakeReady(
+  Vdbe *p,                       /* The VDBE */
+  int nVar,                      /* Number of '?' see in the SQL statement */
+  int nMem,                      /* Number of memory cells to allocate */
+  int nCursor,                   /* Number of cursors to allocate */
+  int nArg,                      /* Maximum number of args in SubPrograms */
+  int isExplain,                 /* True if the EXPLAIN keywords is present */
+  int usesStmtJournal            /* True to set Vdbe.usesStmtJournal */
+){
+  int n;
+  sqlite3 *db = p->db;
 
-/* Opcode: Real * P2 * P4 *
-**
-** P4 is a pointer to a 64-bit floating point value.
-** Write that value into register P2.
-*/
-case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
-  pOut->flags = MEM_Real;
-  assert( !sqlite3IsNaN(*pOp->p4.pReal) );
-  pOut->r = *pOp->p4.pReal;
-  break;
-}
+  assert( p!=0 );
+  assert( p->magic==VDBE_MAGIC_INIT );
 
-/* Opcode: String8 * P2 * P4 *
-**
-** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
-** into an OP_String before it is executed for the first time.
-*/
-case OP_String8: {         /* same as TK_STRING, out2-prerelease */
-  assert( pOp->p4.z!=0 );
-  pOp->opcode = OP_String;
-  pOp->p1 = strlen(pOp->p4.z);
+  /* There should be at least one opcode.
+  */
+  assert( p->nOp>0 );
 
-#ifndef SQLITE_OMIT_UTF16
-  if( encoding!=SQLITE_UTF8 ){
-    sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
-    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
-    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pOut) ) goto no_mem;
-    pOut->zMalloc = 0;
-    pOut->flags |= MEM_Static;
-    pOut->flags &= ~MEM_Dyn;
-    if( pOp->p4type==P4_DYNAMIC ){
-      sqlite3_free(pOp->p4.z);
+  /* Set the magic to VDBE_MAGIC_RUN sooner rather than later. */
+  p->magic = VDBE_MAGIC_RUN;
+
+  /* For each cursor required, also allocate a memory cell. Memory
+  ** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
+  ** the vdbe program. Instead they are used to allocate space for
+  ** VdbeCursor/BtCursor structures. The blob of memory associated with 
+  ** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
+  ** stores the blob of memory associated with cursor 1, etc.
+  **
+  ** See also: allocateCursor().
+  */
+  nMem += nCursor;
+
+  /* Allocate space for memory registers, SQL variables, VDBE cursors and 
+  ** an array to marshal SQL function arguments in. This is only done the
+  ** first time this function is called for a given VDBE, not when it is
+  ** being called from sqlite3_reset() to reset the virtual machine.
+  */
+  if( nVar>=0 && ALWAYS(db->mallocFailed==0) ){
+    u8 *zCsr = (u8 *)&p->aOp[p->nOp];
+    u8 *zEnd = (u8 *)&p->aOp[p->nOpAlloc];
+    int nByte;
+    resolveP2Values(p, &nArg);
+    p->usesStmtJournal = (u8)usesStmtJournal;
+    if( isExplain && nMem<10 ){
+      nMem = 10;
     }
-    pOp->p4type = P4_DYNAMIC;
-    pOp->p4.z = pOut->z;
-    pOp->p1 = pOut->n;
-    if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-      goto too_big;
+    memset(zCsr, 0, zEnd-zCsr);
+    zCsr += (zCsr - (u8*)0)&7;
+    assert( EIGHT_BYTE_ALIGNMENT(zCsr) );
+
+    do {
+      nByte = 0;
+      allocSpace((char*)&p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte);
+      allocSpace((char*)&p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte);
+      allocSpace((char*)&p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte);
+      allocSpace((char*)&p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte);
+      allocSpace((char*)&p->apCsr, 
+                 nCursor*sizeof(VdbeCursor*), &zCsr, zEnd, &nByte
+      );
+      if( nByte ){
+        p->pFree = sqlite3DbMallocZero(db, nByte);
+      }
+      zCsr = p->pFree;
+      zEnd = &zCsr[nByte];
+    }while( nByte && !db->mallocFailed );
+
+    p->nCursor = (u16)nCursor;
+    if( p->aVar ){
+      p->nVar = (u16)nVar;
+      for(n=0; n<nVar; n++){
+        p->aVar[n].flags = MEM_Null;
+        p->aVar[n].db = db;
+      }
+    }
+    if( p->aMem ){
+      p->aMem--;                      /* aMem[] goes from 1..nMem */
+      p->nMem = nMem;                 /*       not from 0..nMem-1 */
+      for(n=1; n<=nMem; n++){
+        p->aMem[n].flags = MEM_Null;
+        p->aMem[n].db = db;
+      }
     }
-    UPDATE_MAX_BLOBSIZE(pOut);
-    break;
+  }
+#ifdef SQLITE_DEBUG
+  for(n=1; n<p->nMem; n++){
+    assert( p->aMem[n].db==db );
   }
 #endif
-  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
+
+  p->pc = -1;
+  p->rc = SQLITE_OK;
+  p->errorAction = OE_Abort;
+  p->explain |= isExplain;
+  p->magic = VDBE_MAGIC_RUN;
+  p->nChange = 0;
+  p->cacheCtr = 1;
+  p->minWriteFileFormat = 255;
+  p->iStatement = 0;
+#ifdef VDBE_PROFILE
+  {
+    int i;
+    for(i=0; i<p->nOp; i++){
+      p->aOp[i].cnt = 0;
+      p->aOp[i].cycles = 0;
+    }
   }
-  /* Fall through to the next case, OP_String */
-}
-  
-/* Opcode: String P1 P2 * P4 *
-**
-** The string value P4 of length P1 (bytes) is stored in register P2.
-*/
-case OP_String: {          /* out2-prerelease */
-  assert( pOp->p4.z!=0 );
-  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
-  pOut->z = pOp->p4.z;
-  pOut->n = pOp->p1;
-  pOut->enc = encoding;
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
+#endif
 }
 
-/* Opcode: Null * P2 * * *
-**
-** Write a NULL into register P2.
+/*
+** Close a VDBE cursor and release all the resources that cursor 
+** happens to hold.
 */
-case OP_Null: {           /* out2-prerelease */
-  break;
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
+  if( pCx==0 ){
+    return;
+  }
+  if( pCx->pBt ){
+    sqlite3BtreeClose(pCx->pBt);
+    /* The pCx->pCursor will be close automatically, if it exists, by
+    ** the call above. */
+  }else if( pCx->pCursor ){
+    sqlite3BtreeCloseCursor(pCx->pCursor);
+  }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( pCx->pVtabCursor ){
+    sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
+    const sqlite3_module *pModule = pCx->pModule;
+    p->inVtabMethod = 1;
+    (void)sqlite3SafetyOff(p->db);
+    pModule->xClose(pVtabCursor);
+    (void)sqlite3SafetyOn(p->db);
+    p->inVtabMethod = 0;
+  }
+#endif
 }
 
-
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-/* Opcode: Blob P1 P2 * P4
-**
-** P4 points to a blob of data P1 bytes long.  Store this
-** blob in register P2. This instruction is not coded directly
-** by the compiler. Instead, the compiler layer specifies
-** an OP_HexBlob opcode, with the hex string representation of
-** the blob as P4. This opcode is transformed to an OP_Blob
-** the first time it is executed.
+/*
+** Copy the values stored in the VdbeFrame structure to its Vdbe. This
+** is used, for example, when a trigger sub-program is halted to restore
+** control to the main program.
 */
-case OP_Blob: {                /* out2-prerelease */
-  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
-  sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
-  pOut->enc = encoding;
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *pFrame){
+  Vdbe *v = pFrame->v;
+  v->aOp = pFrame->aOp;
+  v->nOp = pFrame->nOp;
+  v->aMem = pFrame->aMem;
+  v->nMem = pFrame->nMem;
+  v->apCsr = pFrame->apCsr;
+  v->nCursor = pFrame->nCursor;
+  v->db->lastRowid = pFrame->lastRowid;
+  v->nChange = pFrame->nChange;
+  return pFrame->pc;
 }
-#endif /* SQLITE_OMIT_BLOB_LITERAL */
 
-/* Opcode: Variable P1 P2 * * *
+/*
+** Close all cursors.
 **
-** The value of variable P1 is written into register P2. A variable is
-** an unknown in the original SQL string as handed to sqlite3_compile().
-** Any occurance of the '?' character in the original SQL is considered
-** a variable.  Variables in the SQL string are number from left to
-** right beginning with 1.  The values of variables are set using the
-** sqlite3_bind() API.
+** Also release any dynamic memory held by the VM in the Vdbe.aMem memory 
+** cell array. This is necessary as the memory cell array may contain
+** pointers to VdbeFrame objects, which may in turn contain pointers to
+** open cursors.
 */
-case OP_Variable: {           /* out2-prerelease */
-  int j = pOp->p1 - 1;
-  Mem *pVar;
-  assert( j>=0 && j<p->nVar );
-
-  pVar = &p->aVar[j];
-  if( sqlite3VdbeMemTooBig(pVar) ){
-    goto too_big;
+static void closeAllCursors(Vdbe *p){
+  if( p->pFrame ){
+    VdbeFrame *pFrame = p->pFrame;
+    for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
+    sqlite3VdbeFrameRestore(pFrame);
   }
-  sqlite3VdbeMemShallowCopy(pOut, &p->aVar[j], MEM_Static);
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: Move P1 P2 * * *
-**
-** Move the value in register P1 over into register P2.  Register P1
-** is left holding a NULL.  It is an error for P1 and P2 to be the
-** same register.
-*/
-case OP_Move: {
-  char *zMalloc;
-  assert( pOp->p1>0 );
-  assert( pOp->p1<=p->nMem );
-  pIn1 = &p->aMem[pOp->p1];
-  REGISTER_TRACE(pOp->p1, pIn1);
-  assert( pOp->p2>0 );
-  assert( pOp->p2<=p->nMem );
-  pOut = &p->aMem[pOp->p2];
-  assert( pOut!=pIn1 );
-  zMalloc = pOut->zMalloc;
-  pOut->zMalloc = 0;
-  sqlite3VdbeMemMove(pOut, pIn1);
-  pIn1->zMalloc = zMalloc;
-  REGISTER_TRACE(pOp->p2, pOut);
-  break;
-}
+  p->pFrame = 0;
+  p->nFrame = 0;
 
-/* Opcode: Copy P1 P2 * * *
-**
-** Make a copy of register P1 into register P2.
-**
-** This instruction makes a deep copy of the value.  A duplicate
-** is made of any string or blob constant.  See also OP_SCopy.
-*/
-case OP_Copy: {
-  assert( pOp->p1>0 );
-  assert( pOp->p1<=p->nMem );
-  pIn1 = &p->aMem[pOp->p1];
-  REGISTER_TRACE(pOp->p1, pIn1);
-  assert( pOp->p2>0 );
-  assert( pOp->p2<=p->nMem );
-  pOut = &p->aMem[pOp->p2];
-  assert( pOut!=pIn1 );
-  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-  Deephemeralize(pOut);
-  REGISTER_TRACE(pOp->p2, pOut);
-  break;
+  if( p->apCsr ){
+    int i;
+    for(i=0; i<p->nCursor; i++){
+      VdbeCursor *pC = p->apCsr[i];
+      if( pC ){
+        sqlite3VdbeFreeCursor(p, pC);
+        p->apCsr[i] = 0;
+      }
+    }
+  }
+  if( p->aMem ){
+    releaseMemArray(&p->aMem[1], p->nMem);
+  }
 }
 
-/* Opcode: SCopy P1 P2 * * *
-**
-** Make a shallow copy of register P1 into register P2.
+/*
+** Clean up the VM after execution.
 **
-** This instruction makes a shallow copy of the value.  If the value
-** is a string or blob, then the copy is only a pointer to the
-** original and hence if the original changes so will the copy.
-** Worse, if the original is deallocated, the copy becomes invalid.
-** Thus the program must guarantee that the original will not change
-** during the lifetime of the copy.  Use OP_Copy to make a complete
-** copy.
+** This routine will automatically close any cursors, lists, and/or
+** sorters that were left open.  It also deletes the values of
+** variables in the aVar[] array.
 */
-case OP_SCopy: {
-  assert( pOp->p1>0 );
-  assert( pOp->p1<=p->nMem );
-  pIn1 = &p->aMem[pOp->p1];
-  REGISTER_TRACE(pOp->p1, pIn1);
-  assert( pOp->p2>0 );
-  assert( pOp->p2<=p->nMem );
-  pOut = &p->aMem[pOp->p2];
-  assert( pOut!=pIn1 );
-  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-  REGISTER_TRACE(pOp->p2, pOut);
-  break;
-}
+static void Cleanup(Vdbe *p){
+  sqlite3 *db = p->db;
 
-/* Opcode: ResultRow P1 P2 * * *
-**
-** The registers P1 throught P1+P2-1 contain a single row of
-** results. This opcode causes the sqlite3_step() call to terminate
-** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
-** structure to provide access to the top P1 values as the result
-** row.
-*/
-case OP_ResultRow: {
-  Mem *pMem;
+#ifdef SQLITE_DEBUG
+  /* Execute assert() statements to ensure that the Vdbe.apCsr[] and 
+  ** Vdbe.aMem[] arrays have already been cleaned up.  */
   int i;
-  assert( p->nResColumn==pOp->p2 );
-  assert( pOp->p1>0 );
-  assert( pOp->p1+pOp->p2<=p->nMem );
-
-  /* Invalidate all ephemeral cursor row caches */
-  p->cacheCtr = (p->cacheCtr + 2)|1;
-
-  /* Make sure the results of the current row are \000 terminated
-  ** and have an assigned type.  The results are deephemeralized as
-  ** as side effect.
-  */
-  pMem = p->pResultSet = &p->aMem[pOp->p1];
-  for(i=0; i<pOp->p2; i++){
-    sqlite3VdbeMemNulTerminate(&pMem[i]);
-    storeTypeInfo(&pMem[i], encoding);
-  }
-  if( db->mallocFailed ) goto no_mem;
+  for(i=0; i<p->nCursor; i++) assert( p->apCsr==0 || p->apCsr[i]==0 );
+  for(i=1; i<=p->nMem; i++) assert( p->aMem==0 || p->aMem[i].flags==MEM_Null );
+#endif
 
-  /* Return SQLITE_ROW
-  */
-  p->nCallback++;
-  p->pc = pc + 1;
-  rc = SQLITE_ROW;
-  goto vdbe_return;
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = 0;
+  p->pResultSet = 0;
 }
 
-/* Opcode: Concat P1 P2 P3 * *
-**
-** Add the text in register P1 onto the end of the text in
-** register P2 and store the result in register P3.
-** If either the P1 or P2 text are NULL then store NULL in P3.
-**
-**   P3 = P2 || P1
-**
-** It is illegal for P1 and P3 to be the same register. Sometimes,
-** if P3 is the same register as P2, the implementation is able
-** to avoid a memcpy().
+/*
+** Set the number of result columns that will be returned by this SQL
+** statement. This is now set at compile time, rather than during
+** execution of the vdbe program so that sqlite3_column_count() can
+** be called on an SQL statement before sqlite3_step().
 */
-case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
-  i64 nByte;
+SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
+  Mem *pColName;
+  int n;
+  sqlite3 *db = p->db;
 
-  assert( pIn1!=pOut );
-  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-    break;
-  }
-  ExpandBlob(pIn1);
-  Stringify(pIn1, encoding);
-  ExpandBlob(pIn2);
-  Stringify(pIn2, encoding);
-  nByte = pIn1->n + pIn2->n;
-  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-  MemSetTypeFlag(pOut, MEM_Str);
-  if( sqlite3VdbeMemGrow(pOut, nByte+2, pOut==pIn2) ){
-    goto no_mem;
-  }
-  if( pOut!=pIn2 ){
-    memcpy(pOut->z, pIn2->z, pIn2->n);
+  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
+  sqlite3DbFree(db, p->aColName);
+  n = nResColumn*COLNAME_N;
+  p->nResColumn = (u16)nResColumn;
+  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
+  if( p->aColName==0 ) return;
+  while( n-- > 0 ){
+    pColName->flags = MEM_Null;
+    pColName->db = p->db;
+    pColName++;
   }
-  memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
-  pOut->z[nByte] = 0;
-  pOut->z[nByte+1] = 0;
-  pOut->flags |= MEM_Term;
-  pOut->n = nByte;
-  pOut->enc = encoding;
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
 }
 
-/* Opcode: Add P1 P2 P3 * *
-**
-** Add the value in register P1 to the value in register P2
-** and store the result in regiser P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: Multiply P1 P2 P3 * *
-**
-**
-** Multiply the value in regiser P1 by the value in regiser P2
-** and store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: Subtract P1 P2 P3 * *
-**
-** Subtract the value in register P1 from the value in register P2
-** and store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: Divide P1 P2 P3 * *
+/*
+** Set the name of the idx'th column to be returned by the SQL statement.
+** zName must be a pointer to a nul terminated string.
 **
-** Divide the value in register P1 by the value in register P2
-** and store the result in register P3.  If the value in register P2
-** is zero, then the result is NULL.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: Remainder P1 P2 P3 * *
+** This call must be made after a call to sqlite3VdbeSetNumCols().
 **
-** Compute the remainder after integer division of the value in
-** register P1 by the value in register P2 and store the result in P3. 
-** If the value in register P2 is zero the result is NULL.
-** If either operand is NULL, the result is NULL.
+** The final parameter, xDel, must be one of SQLITE_DYNAMIC, SQLITE_STATIC
+** or SQLITE_TRANSIENT. If it is SQLITE_DYNAMIC, then the buffer pointed
+** to by zName will be freed by sqlite3DbFree() when the vdbe is destroyed.
 */
-case OP_Add:                   /* same as TK_PLUS, in1, in2, out3 */
-case OP_Subtract:              /* same as TK_MINUS, in1, in2, out3 */
-case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
-case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
-case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
-  int flags;
-  flags = pIn1->flags | pIn2->flags;
-  if( (flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
-  if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
-    i64 a, b;
-    a = pIn1->u.i;
-    b = pIn2->u.i;
-    switch( pOp->opcode ){
-      case OP_Add:         b += a;       break;
-      case OP_Subtract:    b -= a;       break;
-      case OP_Multiply:    b *= a;       break;
-      case OP_Divide: {
-        if( a==0 ) goto arithmetic_result_is_null;
-        /* Dividing the largest possible negative 64-bit integer (1<<63) by 
-        ** -1 returns an integer too large to store in a 64-bit data-type. On
-        ** some architectures, the value overflows to (1<<63). On others,
-        ** a SIGFPE is issued. The following statement normalizes this
-        ** behaviour so that all architectures behave as if integer 
-        ** overflow occured.
-        */
-        if( a==-1 && b==SMALLEST_INT64 ) a = 1;
-        b /= a;
-        break;
-      }
-      default: {
-        if( a==0 ) goto arithmetic_result_is_null;
-        if( a==-1 ) a = 1;
-        b %= a;
-        break;
-      }
-    }
-    pOut->u.i = b;
-    MemSetTypeFlag(pOut, MEM_Int);
-  }else{
-    double a, b;
-    a = sqlite3VdbeRealValue(pIn1);
-    b = sqlite3VdbeRealValue(pIn2);
-    switch( pOp->opcode ){
-      case OP_Add:         b += a;       break;
-      case OP_Subtract:    b -= a;       break;
-      case OP_Multiply:    b *= a;       break;
-      case OP_Divide: {
-        if( a==0.0 ) goto arithmetic_result_is_null;
-        b /= a;
-        break;
-      }
-      default: {
-        i64 ia = (i64)a;
-        i64 ib = (i64)b;
-        if( ia==0 ) goto arithmetic_result_is_null;
-        if( ia==-1 ) ia = 1;
-        b = ib % ia;
-        break;
-      }
-    }
-    if( sqlite3IsNaN(b) ){
-      goto arithmetic_result_is_null;
-    }
-    pOut->r = b;
-    MemSetTypeFlag(pOut, MEM_Real);
-    if( (flags & MEM_Real)==0 ){
-      sqlite3VdbeIntegerAffinity(pOut);
-    }
+SQLITE_PRIVATE int sqlite3VdbeSetColName(
+  Vdbe *p,                         /* Vdbe being configured */
+  int idx,                         /* Index of column zName applies to */
+  int var,                         /* One of the COLNAME_* constants */
+  const char *zName,               /* Pointer to buffer containing name */
+  void (*xDel)(void*)              /* Memory management strategy for zName */
+){
+  int rc;
+  Mem *pColName;
+  assert( idx<p->nResColumn );
+  assert( var<COLNAME_N );
+  if( p->db->mallocFailed ){
+    assert( !zName || xDel!=SQLITE_DYNAMIC );
+    return SQLITE_NOMEM;
   }
-  break;
-
-arithmetic_result_is_null:
-  sqlite3VdbeMemSetNull(pOut);
-  break;
-}
-
-/* Opcode: CollSeq * * P4
-**
-** P4 is a pointer to a CollSeq struct. If the next call to a user function
-** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will
-** be returned. This is used by the built-in min(), max() and nullif()
-** functions.
-**
-** The interface used by the implementation of the aforementioned functions
-** to retrieve the collation sequence set by this opcode is not available
-** publicly, only to user functions defined in func.c.
-*/
-case OP_CollSeq: {
-  assert( pOp->p4type==P4_COLLSEQ );
-  break;
+  assert( p->aColName!=0 );
+  pColName = &(p->aColName[idx+var*p->nResColumn]);
+  rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, xDel);
+  assert( rc!=0 || !zName || (pColName->flags&MEM_Term)!=0 );
+  return rc;
 }
 
-/* Opcode: Function P1 P2 P3 P4 P5
-**
-** Invoke a user function (P4 is a pointer to a Function structure that
-** defines the function) with P5 arguments taken from register P2 and
-** successors.  The result of the function is stored in register P3.
-** Register P3 must not be one of the function inputs.
-**
-** P1 is a 32-bit bitmask indicating whether or not each argument to the 
-** function was determined to be constant at compile time. If the first
-** argument was constant then bit 0 of P1 is set. This is used to determine
-** whether meta data associated with a user function argument using the
-** sqlite3_set_auxdata() API may be safely retained until the next
-** invocation of this opcode.
-**
-** See also: AggStep and AggFinal
+/*
+** A read or write transaction may or may not be active on database handle
+** db. If a transaction is active, commit it. If there is a
+** write-transaction spanning more than one database file, this routine
+** takes care of the master journal trickery.
 */
-case OP_Function: {
+static int vdbeCommit(sqlite3 *db, Vdbe *p){
   int i;
-  Mem *pArg;
-  sqlite3_context ctx;
-  sqlite3_value **apVal;
-  int n = pOp->p5;
+  int nTrans = 0;  /* Number of databases with an active write-transaction */
+  int rc = SQLITE_OK;
+  int needXcommit = 0;
 
-  apVal = p->apArg;
-  assert( apVal || n==0 );
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+  /* With this option, sqlite3VtabSync() is defined to be simply 
+  ** SQLITE_OK so p is not used. 
+  */
+  UNUSED_PARAMETER(p);
+#endif
 
-  assert( n==0 || (pOp->p2>0 && pOp->p2+n<=p->nMem) );
-  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
-  pArg = &p->aMem[pOp->p2];
-  for(i=0; i<n; i++, pArg++){
-    apVal[i] = pArg;
-    storeTypeInfo(pArg, encoding);
-    REGISTER_TRACE(pOp->p2, pArg);
+  /* Before doing anything else, call the xSync() callback for any
+  ** virtual module tables written in this transaction. This has to
+  ** be done before determining whether a master journal file is 
+  ** required, as an xSync() callback may add an attached database
+  ** to the transaction.
+  */
+  rc = sqlite3VtabSync(db, &p->zErrMsg);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
 
-  assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
-  if( pOp->p4type==P4_FUNCDEF ){
-    ctx.pFunc = pOp->p4.pFunc;
-    ctx.pVdbeFunc = 0;
-  }else{
-    ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
-    ctx.pFunc = ctx.pVdbeFunc->pFunc;
+  /* This loop determines (a) if the commit hook should be invoked and
+  ** (b) how many database files have open write transactions, not 
+  ** including the temp database. (b) is important because if more than 
+  ** one database file has an open write transaction, a master journal
+  ** file is required for an atomic commit.
+  */ 
+  for(i=0; i<db->nDb; i++){ 
+    Btree *pBt = db->aDb[i].pBt;
+    if( sqlite3BtreeIsInTrans(pBt) ){
+      needXcommit = 1;
+      if( i!=1 ) nTrans++;
+    }
   }
 
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut = &p->aMem[pOp->p3];
-  ctx.s.flags = MEM_Null;
-  ctx.s.db = db;
-  ctx.s.xDel = 0;
-  ctx.s.zMalloc = 0;
+  /* If there are any write-transactions at all, invoke the commit hook */
+  if( needXcommit && db->xCommitCallback ){
+    (void)sqlite3SafetyOff(db);
+    rc = db->xCommitCallback(db->pCommitArg);
+    (void)sqlite3SafetyOn(db);
+    if( rc ){
+      return SQLITE_CONSTRAINT;
+    }
+  }
 
-  /* The output cell may already have a buffer allocated. Move
-  ** the pointer to ctx.s so in case the user-function can use
-  ** the already allocated buffer instead of allocating a new one.
+  /* The simple case - no more than one database file (not counting the
+  ** TEMP database) has a transaction active.   There is no need for the
+  ** master-journal.
+  **
+  ** If the return value of sqlite3BtreeGetFilename() is a zero length
+  ** string, it means the main database is :memory: or a temp file.  In 
+  ** that case we do not support atomic multi-file commits, so use the 
+  ** simple case then too.
   */
-  sqlite3VdbeMemMove(&ctx.s, pOut);
-  MemSetTypeFlag(&ctx.s, MEM_Null);
+  if( 0==sqlite3Strlen30(sqlite3BtreeGetFilename(db->aDb[0].pBt))
+   || nTrans<=1
+  ){
+    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
+      Btree *pBt = db->aDb[i].pBt;
+      if( pBt ){
+        rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
+      }
+    }
 
-  ctx.isError = 0;
-  if( ctx.pFunc->needCollSeq ){
-    assert( pOp>p->aOp );
-    assert( pOp[-1].p4type==P4_COLLSEQ );
-    assert( pOp[-1].opcode==OP_CollSeq );
-    ctx.pColl = pOp[-1].p4.pColl;
-  }
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  (*ctx.pFunc->xFunc)(&ctx, n, apVal);
-  if( sqlite3SafetyOn(db) ){
-    sqlite3VdbeMemRelease(&ctx.s);
-    goto abort_due_to_misuse;
-  }
-  if( db->mallocFailed ){
-    /* Even though a malloc() has failed, the implementation of the
-    ** user function may have called an sqlite3_result_XXX() function
-    ** to return a value. The following call releases any resources
-    ** associated with such a value.
-    **
-    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
-    ** fails also (the if(...) statement above). But if people are
-    ** misusing sqlite, they have bigger problems than a leaked value.
+    /* Do the commit only if all databases successfully complete phase 1. 
+    ** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
+    ** IO error while deleting or truncating a journal file. It is unlikely,
+    ** but could happen. In this case abandon processing and return the error.
     */
-    sqlite3VdbeMemRelease(&ctx.s);
-    goto no_mem;
+    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
+      Btree *pBt = db->aDb[i].pBt;
+      if( pBt ){
+        rc = sqlite3BtreeCommitPhaseTwo(pBt);
+      }
+    }
+    if( rc==SQLITE_OK ){
+      sqlite3VtabCommit(db);
+    }
   }
 
-  /* If any auxilary data functions have been called by this user function,
-  ** immediately call the destructor for any non-static values.
+  /* The complex case - There is a multi-file write-transaction active.
+  ** This requires a master journal file to ensure the transaction is
+  ** committed atomicly.
   */
-  if( ctx.pVdbeFunc ){
-    sqlite3VdbeDeleteAuxData(ctx.pVdbeFunc, pOp->p1);
-    pOp->p4.pVdbeFunc = ctx.pVdbeFunc;
-    pOp->p4type = P4_VDBEFUNC;
-  }
-
-  /* If the function returned an error, throw an exception */
-  if( ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, sqlite3_value_text(&ctx.s), (char*)0);
-    rc = ctx.isError;
-  }
+#ifndef SQLITE_OMIT_DISKIO
+  else{
+    sqlite3_vfs *pVfs = db->pVfs;
+    int needSync = 0;
+    char *zMaster = 0;   /* File-name for the master journal */
+    char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
+    sqlite3_file *pMaster = 0;
+    i64 offset = 0;
+    int res;
 
-  /* Copy the result of the function into register P3 */
-  sqlite3VdbeChangeEncoding(&ctx.s, encoding);
-  sqlite3VdbeMemMove(pOut, &ctx.s);
-  if( sqlite3VdbeMemTooBig(pOut) ){
-    goto too_big;
-  }
-  REGISTER_TRACE(pOp->p3, pOut);
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
+    /* Select a master journal file name */
+    do {
+      u32 iRandom;
+      sqlite3DbFree(db, zMaster);
+      sqlite3_randomness(sizeof(iRandom), &iRandom);
+      zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, iRandom&0x7fffffff);
+      if( !zMaster ){
+        return SQLITE_NOMEM;
+      }
+      rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
+    }while( rc==SQLITE_OK && res );
+    if( rc==SQLITE_OK ){
+      /* Open the master journal. */
+      rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster, 
+          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
+          SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_MASTER_JOURNAL, 0
+      );
+    }
+    if( rc!=SQLITE_OK ){
+      sqlite3DbFree(db, zMaster);
+      return rc;
+    }
+ 
+    /* Write the name of each database file in the transaction into the new
+    ** master journal file. If an error occurs at this point close
+    ** and delete the master journal file. All the individual journal files
+    ** still have 'null' as the master journal pointer, so they will roll
+    ** back independently if a failure occurs.
+    */
+    for(i=0; i<db->nDb; i++){
+      Btree *pBt = db->aDb[i].pBt;
+      if( i==1 ) continue;   /* Ignore the TEMP database */
+      if( sqlite3BtreeIsInTrans(pBt) ){
+        char const *zFile = sqlite3BtreeGetJournalname(pBt);
+        if( zFile[0]==0 ) continue;  /* Ignore :memory: databases */
+        if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
+          needSync = 1;
+        }
+        rc = sqlite3OsWrite(pMaster, zFile, sqlite3Strlen30(zFile)+1, offset);
+        offset += sqlite3Strlen30(zFile)+1;
+        if( rc!=SQLITE_OK ){
+          sqlite3OsCloseFree(pMaster);
+          sqlite3OsDelete(pVfs, zMaster, 0);
+          sqlite3DbFree(db, zMaster);
+          return rc;
+        }
+      }
+    }
 
-/* Opcode: BitAnd P1 P2 P3 * *
-**
-** Take the bit-wise AND of the values in register P1 and P2 and
-** store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: BitOr P1 P2 P3 * *
-**
-** Take the bit-wise OR of the values in register P1 and P2 and
-** store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: ShiftLeft P1 P2 P3 * *
-**
-** Shift the integer value in register P2 to the left by the
-** number of bits specified by the integer in regiser P1.
-** Store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: ShiftRight P1 P2 P3 * *
-**
-** Shift the integer value in register P2 to the right by the
-** number of bits specified by the integer in register P1.
-** Store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */
-case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
-case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
-case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
-  i64 a, b;
+    /* Sync the master journal file. If the IOCAP_SEQUENTIAL device
+    ** flag is set this is not required.
+    */
+    if( needSync 
+     && 0==(sqlite3OsDeviceCharacteristics(pMaster)&SQLITE_IOCAP_SEQUENTIAL)
+     && SQLITE_OK!=(rc = sqlite3OsSync(pMaster, SQLITE_SYNC_NORMAL))
+    ){
+      sqlite3OsCloseFree(pMaster);
+      sqlite3OsDelete(pVfs, zMaster, 0);
+      sqlite3DbFree(db, zMaster);
+      return rc;
+    }
 
-  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-    break;
-  }
-  a = sqlite3VdbeIntValue(pIn2);
-  b = sqlite3VdbeIntValue(pIn1);
-  switch( pOp->opcode ){
-    case OP_BitAnd:      a &= b;     break;
-    case OP_BitOr:       a |= b;     break;
-    case OP_ShiftLeft:   a <<= b;    break;
-    default:  assert( pOp->opcode==OP_ShiftRight );
-                         a >>= b;    break;
-  }
-  pOut->u.i = a;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
+    /* Sync all the db files involved in the transaction. The same call
+    ** sets the master journal pointer in each individual journal. If
+    ** an error occurs here, do not delete the master journal file.
+    **
+    ** If the error occurs during the first call to
+    ** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
+    ** master journal file will be orphaned. But we cannot delete it,
+    ** in case the master journal file name was written into the journal
+    ** file before the failure occurred.
+    */
+    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
+      Btree *pBt = db->aDb[i].pBt;
+      if( pBt ){
+        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
+      }
+    }
+    sqlite3OsCloseFree(pMaster);
+    if( rc!=SQLITE_OK ){
+      sqlite3DbFree(db, zMaster);
+      return rc;
+    }
 
-/* Opcode: AddImm  P1 P2 * * *
-** 
-** Add the constant P2 the value in register P1.
-** The result is always an integer.
-**
-** To force any register to be an integer, just add 0.
-*/
-case OP_AddImm: {            /* in1 */
-  sqlite3VdbeMemIntegerify(pIn1);
-  pIn1->u.i += pOp->p2;
-  break;
-}
+    /* Delete the master journal file. This commits the transaction. After
+    ** doing this the directory is synced again before any individual
+    ** transaction files are deleted.
+    */
+    rc = sqlite3OsDelete(pVfs, zMaster, 1);
+    sqlite3DbFree(db, zMaster);
+    zMaster = 0;
+    if( rc ){
+      return rc;
+    }
 
-/* Opcode: ForceInt P1 P2 P3 * *
-**
-** Convert value in register P1 into an integer.  If the value 
-** in P1 is not numeric (meaning that is is a NULL or a string that
-** does not look like an integer or floating point number) then
-** jump to P2.  If the value in P1 is numeric then
-** convert it into the least integer that is greater than or equal to its
-** current value if P3==0, or to the least integer that is strictly
-** greater than its current value if P3==1.
-*/
-case OP_ForceInt: {            /* jump, in1 */
-  i64 v;
-  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
-  if( (pIn1->flags & (MEM_Int|MEM_Real))==0 ){
-    pc = pOp->p2 - 1;
-    break;
-  }
-  if( pIn1->flags & MEM_Int ){
-    v = pIn1->u.i + (pOp->p3!=0);
-  }else{
-    assert( pIn1->flags & MEM_Real );
-    v = (sqlite3_int64)pIn1->r;
-    if( pIn1->r>(double)v ) v++;
-    if( pOp->p3 && pIn1->r==(double)v ) v++;
+    /* All files and directories have already been synced, so the following
+    ** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
+    ** deleting or truncating journals. If something goes wrong while
+    ** this is happening we don't really care. The integrity of the
+    ** transaction is already guaranteed, but some stray 'cold' journals
+    ** may be lying around. Returning an error code won't help matters.
+    */
+    disable_simulated_io_errors();
+    sqlite3BeginBenignMalloc();
+    for(i=0; i<db->nDb; i++){ 
+      Btree *pBt = db->aDb[i].pBt;
+      if( pBt ){
+        sqlite3BtreeCommitPhaseTwo(pBt);
+      }
+    }
+    sqlite3EndBenignMalloc();
+    enable_simulated_io_errors();
+
+    sqlite3VtabCommit(db);
   }
-  pIn1->u.i = v;
-  MemSetTypeFlag(pIn1, MEM_Int);
-  break;
+#endif
+
+  return rc;
 }
 
-/* Opcode: MustBeInt P1 P2 * * *
-** 
-** Force the value in register P1 to be an integer.  If the value
-** in P1 is not an integer and cannot be converted into an integer
-** without data loss, then jump immediately to P2, or if P2==0
-** raise an SQLITE_MISMATCH exception.
+/* 
+** This routine checks that the sqlite3.activeVdbeCnt count variable
+** matches the number of vdbe's in the list sqlite3.pVdbe that are
+** currently active. An assertion fails if the two counts do not match.
+** This is an internal self-check only - it is not an essential processing
+** step.
+**
+** This is a no-op if NDEBUG is defined.
 */
-case OP_MustBeInt: {            /* jump, in1 */
-  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
-  if( (pIn1->flags & MEM_Int)==0 ){
-    if( pOp->p2==0 ){
-      rc = SQLITE_MISMATCH;
-      goto abort_due_to_error;
-    }else{
-      pc = pOp->p2 - 1;
+#ifndef NDEBUG
+static void checkActiveVdbeCnt(sqlite3 *db){
+  Vdbe *p;
+  int cnt = 0;
+  int nWrite = 0;
+  p = db->pVdbe;
+  while( p ){
+    if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
+      cnt++;
+      if( p->readOnly==0 ) nWrite++;
     }
-  }else{
-    MemSetTypeFlag(pIn1, MEM_Int);
+    p = p->pNext;
   }
-  break;
+  assert( cnt==db->activeVdbeCnt );
+  assert( nWrite==db->writeVdbeCnt );
 }
+#else
+#define checkActiveVdbeCnt(x)
+#endif
 
-/* Opcode: RealAffinity P1 * * * *
-**
-** If register P1 holds an integer convert it to a real value.
+/*
+** For every Btree that in database connection db which 
+** has been modified, "trip" or invalidate each cursor in
+** that Btree might have been modified so that the cursor
+** can never be used again.  This happens when a rollback
+*** occurs.  We have to trip all the other cursors, even
+** cursor from other VMs in different database connections,
+** so that none of them try to use the data at which they
+** were pointing and which now may have been changed due
+** to the rollback.
 **
-** This opcode is used when extracting information from a column that
-** has REAL affinity.  Such column values may still be stored as
-** integers, for space efficiency, but after extraction we want them
-** to have only a real value.
+** Remember that a rollback can delete tables complete and
+** reorder rootpages.  So it is not sufficient just to save
+** the state of the cursor.  We have to invalidate the cursor
+** so that it is never used again.
 */
-case OP_RealAffinity: {                  /* in1 */
-  if( pIn1->flags & MEM_Int ){
-    sqlite3VdbeMemRealify(pIn1);
+static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
+  int i;
+  for(i=0; i<db->nDb; i++){
+    Btree *p = db->aDb[i].pBt;
+    if( p && sqlite3BtreeIsInTrans(p) ){
+      sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
+    }
   }
-  break;
 }
 
-#ifndef SQLITE_OMIT_CAST
-/* Opcode: ToText P1 * * * *
-**
-** Force the value in register P1 to be text.
-** If the value is numeric, convert it to a string using the
-** equivalent of printf().  Blob values are unchanged and
-** are afterwards simply interpreted as text.
+/*
+** If the Vdbe passed as the first argument opened a statement-transaction,
+** close it now. Argument eOp must be either SAVEPOINT_ROLLBACK or
+** SAVEPOINT_RELEASE. If it is SAVEPOINT_ROLLBACK, then the statement
+** transaction is rolled back. If eOp is SAVEPOINT_RELEASE, then the 
+** statement transaction is commtted.
 **
-** A NULL value is not changed by this routine.  It remains NULL.
+** If an IO error occurs, an SQLITE_IOERR_XXX error code is returned. 
+** Otherwise SQLITE_OK.
 */
-case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
-  if( pIn1->flags & MEM_Null ) break;
-  assert( MEM_Str==(MEM_Blob>>3) );
-  pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
-  applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
-  rc = ExpandBlob(pIn1);
-  assert( pIn1->flags & MEM_Str || db->mallocFailed );
-  pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob);
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  break;
-}
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
+  sqlite3 *const db = p->db;
+  int rc = SQLITE_OK;
 
-/* Opcode: ToBlob P1 * * * *
-**
-** Force the value in register P1 to be a BLOB.
-** If the value is numeric, convert it to a string first.
-** Strings are simply reinterpreted as blobs with no change
-** to the underlying data.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
-  if( pIn1->flags & MEM_Null ) break;
-  if( (pIn1->flags & MEM_Blob)==0 ){
-    applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
-    assert( pIn1->flags & MEM_Str || db->mallocFailed );
-  }
-  MemSetTypeFlag(pIn1, MEM_Blob);
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  break;
-}
+  /* If p->iStatement is greater than zero, then this Vdbe opened a 
+  ** statement transaction that should be closed here. The only exception
+  ** is that an IO error may have occured, causing an emergency rollback.
+  ** In this case (db->nStatement==0), and there is nothing to do.
+  */
+  if( db->nStatement && p->iStatement ){
+    int i;
+    const int iSavepoint = p->iStatement-1;
 
-/* Opcode: ToNumeric P1 * * * *
-**
-** Force the value in register P1 to be numeric (either an
-** integer or a floating-point number.)
-** If the value is text or blob, try to convert it to an using the
-** equivalent of atoi() or atof() and store 0 if no such conversion 
-** is possible.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
-  if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
-    sqlite3VdbeMemNumerify(pIn1);
+    assert( eOp==SAVEPOINT_ROLLBACK || eOp==SAVEPOINT_RELEASE);
+    assert( db->nStatement>0 );
+    assert( p->iStatement==(db->nStatement+db->nSavepoint) );
+
+    for(i=0; i<db->nDb; i++){ 
+      int rc2 = SQLITE_OK;
+      Btree *pBt = db->aDb[i].pBt;
+      if( pBt ){
+        if( eOp==SAVEPOINT_ROLLBACK ){
+          rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_ROLLBACK, iSavepoint);
+        }
+        if( rc2==SQLITE_OK ){
+          rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_RELEASE, iSavepoint);
+        }
+        if( rc==SQLITE_OK ){
+          rc = rc2;
+        }
+      }
+    }
+    db->nStatement--;
+    p->iStatement = 0;
+
+    /* If the statement transaction is being rolled back, also restore the 
+    ** database handles deferred constraint counter to the value it had when 
+    ** the statement transaction was opened.  */
+    if( eOp==SAVEPOINT_ROLLBACK ){
+      db->nDeferredCons = p->nStmtDefCons;
+    }
   }
-  break;
+  return rc;
 }
-#endif /* SQLITE_OMIT_CAST */
 
-/* Opcode: ToInt P1 * * * *
+/*
+** If SQLite is compiled to support shared-cache mode and to be threadsafe,
+** this routine obtains the mutex associated with each BtShared structure
+** that may be accessed by the VM passed as an argument. In doing so it
+** sets the BtShared.db member of each of the BtShared structures, ensuring
+** that the correct busy-handler callback is invoked if required.
 **
-** Force the value in register P1 be an integer.  If
-** The value is currently a real number, drop its fractional part.
-** If the value is text or blob, try to convert it to an integer using the
-** equivalent of atoi() and store 0 if no such conversion is possible.
+** If SQLite is not threadsafe but does support shared-cache mode, then
+** sqlite3BtreeEnterAll() is invoked to set the BtShared.db variables
+** of all of BtShared structures accessible via the database handle 
+** associated with the VM. Of course only a subset of these structures
+** will be accessed by the VM, and we could use Vdbe.btreeMask to figure
+** that subset out, but there is no advantage to doing so.
 **
-** A NULL value is not changed by this routine.  It remains NULL.
+** If SQLite is not threadsafe and does not support shared-cache mode, this
+** function is a no-op.
 */
-case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    sqlite3VdbeMemIntegerify(pIn1);
-  }
-  break;
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p){
+#if SQLITE_THREADSAFE
+  sqlite3BtreeMutexArrayEnter(&p->aMutex);
+#else
+  sqlite3BtreeEnterAll(p->db);
+#endif
 }
+#endif
 
-#ifndef SQLITE_OMIT_CAST
-/* Opcode: ToReal P1 * * * *
-**
-** Force the value in register P1 to be a floating point number.
-** If The value is currently an integer, convert it.
-** If the value is text or blob, try to convert it to an integer using the
-** equivalent of atoi() and store 0.0 if no such conversion is possible.
+/*
+** This function is called when a transaction opened by the database 
+** handle associated with the VM passed as an argument is about to be 
+** committed. If there are outstanding deferred foreign key constraint
+** violations, return SQLITE_ERROR. Otherwise, SQLITE_OK.
 **
-** A NULL value is not changed by this routine.  It remains NULL.
+** If there are outstanding FK violations and this function returns 
+** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT and write
+** an error message to it. Then return SQLITE_ERROR.
 */
-case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    sqlite3VdbeMemRealify(pIn1);
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
+  sqlite3 *db = p->db;
+  if( (deferred && db->nDeferredCons>0) || (!deferred && p->nFkConstraint>0) ){
+    p->rc = SQLITE_CONSTRAINT;
+    p->errorAction = OE_Abort;
+    sqlite3SetString(&p->zErrMsg, db, "foreign key constraint failed");
+    return SQLITE_ERROR;
   }
-  break;
+  return SQLITE_OK;
 }
-#endif /* SQLITE_OMIT_CAST */
+#endif
 
-/* Opcode: Lt P1 P2 P3 P4 P5
-**
-** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
-** jump to address P2.  
-**
-** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
-** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
-** bit is clear then fall thru if either operand is NULL.
-**
-** If the SQLITE_NULLEQUAL bit of P5 is set then treat NULL operands
-** as being equal to one another.  Normally NULLs are not equal to 
-** anything including other NULLs.
-**
-** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
-** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 
-** to coerce both inputs according to this affinity before the
-** comparison is made. If the SQLITE_AFF_MASK is 0x00, then numeric
-** affinity is used. Note that the affinity conversions are stored
-** back into the input registers P1 and P3.  So this opcode can cause
-** persistent changes to registers P1 and P3.
-**
-** Once any conversions have taken place, and neither value is NULL, 
-** the values are compared. If both values are blobs then memcmp() is
-** used to determine the results of the comparison.  If both values
-** are text, then the appropriate collating function specified in
-** P4 is  used to do the comparison.  If P4 is not specified then
-** memcmp() is used to compare text string.  If both values are
-** numeric, then a numeric comparison is used. If the two values
-** are of different types, then numbers are considered less than
-** strings and strings are considered less than blobs.
-**
-** If the SQLITE_STOREP2 bit of P5 is set, then do not jump.  Instead,
-** store a boolean result (either 0, or 1, or NULL) in register P2.
-*/
-/* Opcode: Ne P1 P2 P3 P4 P5
-**
-** This works just like the Lt opcode except that the jump is taken if
-** the operands in registers P1 and P3 are not equal.  See the Lt opcode for
-** additional information.
-*/
-/* Opcode: Eq P1 P2 P3 P4 P5
-**
-** This works just like the Lt opcode except that the jump is taken if
-** the operands in registers P1 and P3 are equal.
-** See the Lt opcode for additional information.
-*/
-/* Opcode: Le P1 P2 P3 P4 P5
-**
-** This works just like the Lt opcode except that the jump is taken if
-** the content of register P3 is less than or equal to the content of
-** register P1.  See the Lt opcode for additional information.
-*/
-/* Opcode: Gt P1 P2 P3 P4 P5
+/*
+** This routine is called the when a VDBE tries to halt.  If the VDBE
+** has made changes and is in autocommit mode, then commit those
+** changes.  If a rollback is needed, then do the rollback.
 **
-** This works just like the Lt opcode except that the jump is taken if
-** the content of register P3 is greater than the content of
-** register P1.  See the Lt opcode for additional information.
-*/
-/* Opcode: Ge P1 P2 P3 P4 P5
+** This routine is the only way to move the state of a VM from
+** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT.  It is harmless to
+** call this on a VM that is in the SQLITE_MAGIC_HALT state.
 **
-** This works just like the Lt opcode except that the jump is taken if
-** the content of register P3 is greater than or equal to the content of
-** register P1.  See the Lt opcode for additional information.
+** Return an error code.  If the commit could not complete because of
+** lock contention, return SQLITE_BUSY.  If SQLITE_BUSY is returned, it
+** means the close did not happen and needs to be repeated.
 */
-case OP_Eq:               /* same as TK_EQ, jump, in1, in3 */
-case OP_Ne:               /* same as TK_NE, jump, in1, in3 */
-case OP_Lt:               /* same as TK_LT, jump, in1, in3 */
-case OP_Le:               /* same as TK_LE, jump, in1, in3 */
-case OP_Gt:               /* same as TK_GT, jump, in1, in3 */
-case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
-  int flags;
-  int res;
-  char affinity;
-  Mem x1, x3;
+SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
+  int rc;                         /* Used to store transient return codes */
+  sqlite3 *db = p->db;
 
-  flags = pIn1->flags|pIn3->flags;
+  /* This function contains the logic that determines if a statement or
+  ** transaction will be committed or rolled back as a result of the
+  ** execution of this virtual machine. 
+  **
+  ** If any of the following errors occur:
+  **
+  **     SQLITE_NOMEM
+  **     SQLITE_IOERR
+  **     SQLITE_FULL
+  **     SQLITE_INTERRUPT
+  **
+  ** Then the internal cache might have been left in an inconsistent
+  ** state.  We need to rollback the statement transaction, if there is
+  ** one, or the complete transaction if there is no statement transaction.
+  */
 
-  if( flags&MEM_Null ){
-    if( (pOp->p5 & SQLITE_NULLEQUAL)!=0 ){
-      /*
-      ** When SQLITE_NULLEQUAL set and either operand is NULL
-      ** then both operands are converted to integers prior to being 
-      ** passed down into the normal comparison logic below.  
-      ** NULL operands are converted to zero and non-NULL operands
-      ** are converted to 1.  Thus, for example, with SQLITE_NULLEQUAL
-      ** set,  NULL==NULL is true whereas it would normally NULL.
-      ** Similarly,  NULL!=123 is true.
-      */
-      x1.flags = MEM_Int;
-      x1.u.i = (pIn1->flags & MEM_Null)==0;
-      pIn1 = &x1;
-      x3.flags = MEM_Int;
-      x3.u.i = (pIn3->flags & MEM_Null)==0;
-      pIn3 = &x3;
-    }else{
-      /* If the SQLITE_NULLEQUAL bit is clear and either operand is NULL then
-      ** the result is always NULL.  The jump is taken if the 
-      ** SQLITE_JUMPIFNULL bit is set.
-      */
-      if( pOp->p5 & SQLITE_STOREP2 ){
-        pOut = &p->aMem[pOp->p2];
-        MemSetTypeFlag(pOut, MEM_Null);
-        REGISTER_TRACE(pOp->p2, pOut);
-      }else if( pOp->p5 & SQLITE_JUMPIFNULL ){
-        pc = pOp->p2-1;
-      }
-      break;
-    }
+  if( p->db->mallocFailed ){
+    p->rc = SQLITE_NOMEM;
   }
-
-  affinity = pOp->p5 & SQLITE_AFF_MASK;
-  if( affinity ){
-    applyAffinity(pIn1, affinity, encoding);
-    applyAffinity(pIn3, affinity, encoding);
+  closeAllCursors(p);
+  if( p->magic!=VDBE_MAGIC_RUN ){
+    return SQLITE_OK;
   }
+  checkActiveVdbeCnt(db);
 
-  assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
-  ExpandBlob(pIn1);
-  ExpandBlob(pIn3);
-  res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
-  switch( pOp->opcode ){
-    case OP_Eq:    res = res==0;     break;
-    case OP_Ne:    res = res!=0;     break;
-    case OP_Lt:    res = res<0;      break;
-    case OP_Le:    res = res<=0;     break;
-    case OP_Gt:    res = res>0;      break;
-    default:       res = res>=0;     break;
-  }
+  /* No commit or rollback needed if the program never started */
+  if( p->pc>=0 ){
+    int mrc;   /* Primary error code from p->rc */
+    int eStatementOp = 0;
+    int isSpecialError;            /* Set to true if a 'special' error */
 
-  if( pOp->p5 & SQLITE_STOREP2 ){
-    pOut = &p->aMem[pOp->p2];
-    MemSetTypeFlag(pOut, MEM_Int);
-    pOut->u.i = res;
-    REGISTER_TRACE(pOp->p2, pOut);
-  }else if( res ){
-    pc = pOp->p2-1;
-  }
-  break;
-}
+    /* Lock all btrees used by the statement */
+    sqlite3VdbeMutexArrayEnter(p);
 
-/* Opcode: And P1 P2 P3 * *
-**
-** Take the logical AND of the values in registers P1 and P2 and
-** write the result into register P3.
-**
-** If either P1 or P2 is 0 (false) then the result is 0 even if
-** the other input is NULL.  A NULL and true or two NULLs give
-** a NULL output.
-*/
-/* Opcode: Or P1 P2 P3 * *
-**
-** Take the logical OR of the values in register P1 and P2 and
-** store the answer in register P3.
-**
-** If either P1 or P2 is nonzero (true) then the result is 1 (true)
-** even if the other input is NULL.  A NULL and false or two NULLs
-** give a NULL output.
-*/
-case OP_And:              /* same as TK_AND, in1, in2, out3 */
-case OP_Or: {             /* same as TK_OR, in1, in2, out3 */
-  int v1, v2;    /* 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
+    /* Check for one of the special errors */
+    mrc = p->rc & 0xff;
+    assert( p->rc!=SQLITE_IOERR_BLOCKED );  /* This error no longer exists */
+    isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
+                     || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
+    if( isSpecialError ){
+      /* If the query was read-only, we need do no rollback at all. Otherwise,
+      ** proceed with the special handling.
+      */
+      if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
+        if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
+          eStatementOp = SAVEPOINT_ROLLBACK;
+        }else{
+          /* We are forced to roll back the active transaction. Before doing
+          ** so, abort any other statements this handle currently has active.
+          */
+          invalidateCursorsOnModifiedBtrees(db);
+          sqlite3RollbackAll(db);
+          sqlite3CloseSavepoints(db);
+          db->autoCommit = 1;
+        }
+      }
+    }
 
-  if( pIn1->flags & MEM_Null ){
-    v1 = 2;
-  }else{
-    v1 = sqlite3VdbeIntValue(pIn1)!=0;
-  }
-  if( pIn2->flags & MEM_Null ){
-    v2 = 2;
-  }else{
-    v2 = sqlite3VdbeIntValue(pIn2)!=0;
-  }
-  if( pOp->opcode==OP_And ){
-    static const unsigned char and_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
-    v1 = and_logic[v1*3+v2];
-  }else{
-    static const unsigned char or_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
-    v1 = or_logic[v1*3+v2];
-  }
-  if( v1==2 ){
-    MemSetTypeFlag(pOut, MEM_Null);
-  }else{
-    pOut->u.i = v1;
-    MemSetTypeFlag(pOut, MEM_Int);
-  }
-  break;
-}
-
-/* Opcode: Not P1 * * * *
-**
-** Interpret the value in register P1 as a boolean value.  Replace it
-** with its complement.  If the value in register P1 is NULL its value
-** is unchanged.
-*/
-case OP_Not: {                /* same as TK_NOT, in1 */
-  if( pIn1->flags & MEM_Null ) break;  /* Do nothing to NULLs */
-  sqlite3VdbeMemIntegerify(pIn1);
-  pIn1->u.i = !pIn1->u.i;
-  assert( pIn1->flags&MEM_Int );
-  break;
-}
-
-/* Opcode: BitNot P1 * * * *
-**
-** Interpret the content of register P1 as an integer.  Replace it
-** with its ones-complement.  If the value is originally NULL, leave
-** it unchanged.
-*/
-case OP_BitNot: {             /* same as TK_BITNOT, in1 */
-  if( pIn1->flags & MEM_Null ) break;  /* Do nothing to NULLs */
-  sqlite3VdbeMemIntegerify(pIn1);
-  pIn1->u.i = ~pIn1->u.i;
-  assert( pIn1->flags&MEM_Int );
-  break;
-}
-
-/* Opcode: If P1 P2 P3 * *
-**
-** Jump to P2 if the value in register P1 is true.  The value is
-** is considered true if it is numeric and non-zero.  If the value
-** in P1 is NULL then take the jump if P3 is true.
-*/
-/* Opcode: IfNot P1 P2 P3 * *
-**
-** Jump to P2 if the value in register P1 is False.  The value is
-** is considered true if it has a numeric value of zero.  If the value
-** in P1 is NULL then take the jump if P3 is true.
-*/
-case OP_If:                 /* jump, in1 */
-case OP_IfNot: {            /* jump, in1 */
-  int c;
-  if( pIn1->flags & MEM_Null ){
-    c = pOp->p3;
-  }else{
-#ifdef SQLITE_OMIT_FLOATING_POINT
-    c = sqlite3VdbeIntValue(pIn1);
-#else
-    c = sqlite3VdbeRealValue(pIn1)!=0.0;
-#endif
-    if( pOp->opcode==OP_IfNot ) c = !c;
-  }
-  if( c ){
-    pc = pOp->p2-1;
-  }
-  break;
-}
-
-/* Opcode: IsNull P1 P2 P3 * *
-**
-** Jump to P2 if the value in register P1 is NULL.  If P3 is greater
-** than zero, then check all values reg(P1), reg(P1+1), 
-** reg(P1+2), ..., reg(P1+P3-1).
-*/
-case OP_IsNull: {            /* same as TK_ISNULL, jump, in1 */
-  int n = pOp->p3;
-  assert( pOp->p3==0 || pOp->p1>0 );
-  do{
-    if( (pIn1->flags & MEM_Null)!=0 ){
-      pc = pOp->p2 - 1;
-      break;
-    }
-    pIn1++;
-  }while( --n > 0 );
-  break;
-}
-
-/* Opcode: NotNull P1 P2 * * *
-**
-** Jump to P2 if the value in register P1 is not NULL.  
-*/
-case OP_NotNull: {            /* same as TK_NOTNULL, jump, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: SetNumColumns * P2 * * *
-**
-** This opcode sets the number of columns for the cursor opened by the
-** following instruction to P2.
-**
-** An OP_SetNumColumns is only useful if it occurs immediately before 
-** one of the following opcodes:
-**
-**     OpenRead
-**     OpenWrite
-**     OpenPseudo
-**
-** If the OP_Column opcode is to be executed on a cursor, then
-** this opcode must be present immediately before the opcode that
-** opens the cursor.
-*/
-case OP_SetNumColumns: {
-  break;
-}
-
-/* Opcode: Column P1 P2 P3 P4 *
-**
-** Interpret the data that cursor P1 points to as a structure built using
-** the MakeRecord instruction.  (See the MakeRecord opcode for additional
-** information about the format of the data.)  Extract the P2-th column
-** from this record.  If there are less that (P2+1) 
-** values in the record, extract a NULL.
-**
-** The value extracted is stored in register P3.
-**
-** If the KeyAsData opcode has previously executed on this cursor, then the
-** field might be extracted from the key rather than the data.
-**
-** If the column contains fewer than P2 fields, then extract a NULL.  Or,
-** if the P4 argument is a P4_MEM use the value of the P4 argument as
-** the result.
-*/
-case OP_Column: {
-  u32 payloadSize;   /* Number of bytes in the record */
-  int p1 = pOp->p1;  /* P1 value of the opcode */
-  int p2 = pOp->p2;  /* column number to retrieve */
-  Cursor *pC = 0;    /* The VDBE cursor */
-  char *zRec;        /* Pointer to complete record-data */
-  BtCursor *pCrsr;   /* The BTree cursor */
-  u32 *aType;        /* aType[i] holds the numeric type of the i-th column */
-  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
-  u32 nField;        /* number of fields in the record */
-  int len;           /* The length of the serialized data for the column */
-  int i;             /* Loop counter */
-  char *zData;       /* Part of the record being decoded */
-  Mem *pDest;        /* Where to write the extracted value */
-  Mem sMem;          /* For storing the record being decoded */
-
-  sMem.flags = 0;
-  sMem.db = 0;
-  sMem.zMalloc = 0;
-  assert( p1<p->nCursor );
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pDest = &p->aMem[pOp->p3];
-  MemSetTypeFlag(pDest, MEM_Null);
-
-  /* This block sets the variable payloadSize to be the total number of
-  ** bytes in the record.
-  **
-  ** zRec is set to be the complete text of the record if it is available.
-  ** The complete record text is always available for pseudo-tables
-  ** If the record is stored in a cursor, the complete record text
-  ** might be available in the  pC->aRow cache.  Or it might not be.
-  ** If the data is unavailable,  zRec is set to NULL.
-  **
-  ** We also compute the number of columns in the record.  For cursors,
-  ** the number of columns is stored in the Cursor.nField element.
-  */
-  pC = p->apCsr[p1];
-  assert( pC!=0 );
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  assert( pC->pVtabCursor==0 );
-#endif
-  if( pC->pCursor!=0 ){
-    /* The record is stored in a B-Tree */
-    rc = sqlite3VdbeCursorMoveto(pC);
-    if( rc ) goto abort_due_to_error;
-    zRec = 0;
-    pCrsr = pC->pCursor;
-    if( pC->nullRow ){
-      payloadSize = 0;
-    }else if( pC->cacheStatus==p->cacheCtr ){
-      payloadSize = pC->payloadSize;
-      zRec = (char*)pC->aRow;
-    }else if( pC->isIndex ){
-      i64 payloadSize64;
-      sqlite3BtreeKeySize(pCrsr, &payloadSize64);
-      payloadSize = payloadSize64;
-    }else{
-      sqlite3BtreeDataSize(pCrsr, &payloadSize);
+    /* Check for immediate foreign key violations. */
+    if( p->rc==SQLITE_OK ){
+      sqlite3VdbeCheckFk(p, 0);
     }
-    nField = pC->nField;
-  }else{
-    assert( pC->pseudoTable );
-    /* The record is the sole entry of a pseudo-table */
-    payloadSize = pC->nData;
-    zRec = pC->pData;
-    pC->cacheStatus = CACHE_STALE;
-    assert( payloadSize==0 || zRec!=0 );
-    nField = pC->nField;
-    pCrsr = 0;
-  }
-
-  /* If payloadSize is 0, then just store a NULL */
-  if( payloadSize==0 ){
-    assert( pDest->flags&MEM_Null );
-    goto op_column_out;
-  }
-  if( payloadSize>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-
-  assert( p2<nField );
-
-  /* Read and parse the table header.  Store the results of the parse
-  ** into the record header cache fields of the cursor.
-  */
-  aType = pC->aType;
-  if( pC->cacheStatus==p->cacheCtr ){
-    aOffset = pC->aOffset;
-  }else{
-    u8 *zIdx;        /* Index into header */
-    u8 *zEndHdr;     /* Pointer to first byte after the header */
-    u32 offset;      /* Offset into the data */
-    int szHdrSz;     /* Size of the header size field at start of record */
-    int avail;       /* Number of bytes of available data */
-
-    assert(aType);
-    pC->aOffset = aOffset = &aType[nField];
-    pC->payloadSize = payloadSize;
-    pC->cacheStatus = p->cacheCtr;
-
-    /* Figure out how many bytes are in the header */
-    if( zRec ){
-      zData = zRec;
-    }else{
-      if( pC->isIndex ){
-        zData = (char*)sqlite3BtreeKeyFetch(pCrsr, &avail);
+  
+    /* If the auto-commit flag is set and this is the only active writer 
+    ** VM, then we do either a commit or rollback of the current transaction. 
+    **
+    ** Note: This block also runs if one of the special errors handled 
+    ** above has occurred. 
+    */
+    if( !sqlite3VtabInSync(db) 
+     && db->autoCommit 
+     && db->writeVdbeCnt==(p->readOnly==0) 
+    ){
+      if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
+        if( sqlite3VdbeCheckFk(p, 1) ){
+          sqlite3BtreeMutexArrayLeave(&p->aMutex);
+          return SQLITE_ERROR;
+        }
+        /* The auto-commit flag is true, the vdbe program was successful 
+        ** or hit an 'OR FAIL' constraint and there are no deferred foreign
+        ** key constraints to hold up the transaction. This means a commit 
+        ** is required.  */
+        rc = vdbeCommit(db, p);
+        if( rc==SQLITE_BUSY ){
+          sqlite3BtreeMutexArrayLeave(&p->aMutex);
+          return SQLITE_BUSY;
+        }else if( rc!=SQLITE_OK ){
+          p->rc = rc;
+          sqlite3RollbackAll(db);
+        }else{
+          db->nDeferredCons = 0;
+          sqlite3CommitInternalChanges(db);
+        }
       }else{
-        zData = (char*)sqlite3BtreeDataFetch(pCrsr, &avail);
+        sqlite3RollbackAll(db);
       }
-      /* If KeyFetch()/DataFetch() managed to get the entire payload,
-      ** save the payload in the pC->aRow cache.  That will save us from
-      ** having to make additional calls to fetch the content portion of
-      ** the record.
-      */
-      if( avail>=payloadSize ){
-        zRec = zData;
-        pC->aRow = (u8*)zData;
+      db->nStatement = 0;
+    }else if( eStatementOp==0 ){
+      if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
+        eStatementOp = SAVEPOINT_RELEASE;
+      }else if( p->errorAction==OE_Abort ){
+        eStatementOp = SAVEPOINT_ROLLBACK;
       }else{
-        pC->aRow = 0;
+        invalidateCursorsOnModifiedBtrees(db);
+        sqlite3RollbackAll(db);
+        sqlite3CloseSavepoints(db);
+        db->autoCommit = 1;
       }
     }
-    /* The following assert is true in all cases accept when
-    ** the database file has been corrupted externally.
-    **    assert( zRec!=0 || avail>=payloadSize || avail>=9 ); */
-    szHdrSz = getVarint32((u8*)zData, offset);
-
-    /* The KeyFetch() or DataFetch() above are fast and will get the entire
-    ** record header in most cases.  But they will fail to get the complete
-    ** record header if the record header does not fit on a single page
-    ** in the B-Tree.  When that happens, use sqlite3VdbeMemFromBtree() to
-    ** acquire the complete header text.
+  
+    /* If eStatementOp is non-zero, then a statement transaction needs to
+    ** be committed or rolled back. Call sqlite3VdbeCloseStatement() to
+    ** do so. If this operation returns an error, and the current statement
+    ** error code is SQLITE_OK or SQLITE_CONSTRAINT, then set the error
+    ** code to the new value.
     */
-    if( !zRec && avail<offset ){
-      sMem.flags = 0;
-      sMem.db = 0;
-      rc = sqlite3VdbeMemFromBtree(pCrsr, 0, offset, pC->isIndex, &sMem);
-      if( rc!=SQLITE_OK ){
-        goto op_column_out;
+    if( eStatementOp ){
+      rc = sqlite3VdbeCloseStatement(p, eStatementOp);
+      if( rc && (p->rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT) ){
+        p->rc = rc;
+        sqlite3DbFree(db, p->zErrMsg);
+        p->zErrMsg = 0;
       }
-      zData = sMem.z;
     }
-    zEndHdr = (u8 *)&zData[offset];
-    zIdx = (u8 *)&zData[szHdrSz];
-
-    /* Scan the header and use it to fill in the aType[] and aOffset[]
-    ** arrays.  aType[i] will contain the type integer for the i-th
-    ** column and aOffset[i] will contain the offset from the beginning
-    ** of the record to the start of the data for the i-th column
+  
+    /* If this was an INSERT, UPDATE or DELETE and no statement transaction
+    ** has been rolled back, update the database connection change-counter. 
     */
-    for(i=0; i<nField; i++){
-      if( zIdx<zEndHdr ){
-        aOffset[i] = offset;
-        zIdx += getVarint32(zIdx, aType[i]);
-        offset += sqlite3VdbeSerialTypeLen(aType[i]);
+    if( p->changeCntOn ){
+      if( eStatementOp!=SAVEPOINT_ROLLBACK ){
+        sqlite3VdbeSetChanges(db, p->nChange);
       }else{
-        /* If i is less that nField, then there are less fields in this
-        ** record than SetNumColumns indicated there are columns in the
-        ** table. Set the offset for any extra columns not present in
-        ** the record to 0. This tells code below to store a NULL
-        ** instead of deserializing a value from the record.
-        */
-        aOffset[i] = 0;
+        sqlite3VdbeSetChanges(db, 0);
       }
+      p->nChange = 0;
     }
-    sqlite3VdbeMemRelease(&sMem);
-    sMem.flags = MEM_Null;
-
-    /* If we have read more header data than was contained in the header,
-    ** or if the end of the last field appears to be past the end of the
-    ** record, or if the end of the last field appears to be before the end
-    ** of the record (when all fields present), then we must be dealing 
-    ** with a corrupt database.
-    */
-    if( zIdx>zEndHdr || offset>payloadSize || (zIdx==zEndHdr && offset!=payloadSize) ){
-      rc = SQLITE_CORRUPT_BKPT;
-      goto op_column_out;
+  
+    /* Rollback or commit any schema changes that occurred. */
+    if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
+      sqlite3ResetInternalSchema(db, 0);
+      db->flags = (db->flags | SQLITE_InternChanges);
     }
+
+    /* Release the locks */
+    sqlite3BtreeMutexArrayLeave(&p->aMutex);
   }
 
-  /* Get the column information. If aOffset[p2] is non-zero, then 
-  ** deserialize the value from the record. If aOffset[p2] is zero,
-  ** then there are not enough fields in the record to satisfy the
-  ** request.  In this case, set the value NULL or to P4 if P4 is
-  ** a pointer to a Mem object.
-  */
-  if( aOffset[p2] ){
-    assert( rc==SQLITE_OK );
-    if( zRec ){
-      if( pDest->flags&MEM_Dyn ){
-        sqlite3VdbeSerialGet((u8 *)&zRec[aOffset[p2]], aType[p2], &sMem);
-        sMem.db = db; 
-        rc = sqlite3VdbeMemCopy(pDest, &sMem);
-        assert( !(sMem.flags&MEM_Dyn) );
-        if( rc!=SQLITE_OK ){
-          goto op_column_out;
-        }
-      }else{
-        sqlite3VdbeSerialGet((u8 *)&zRec[aOffset[p2]], aType[p2], pDest);
-      }
-    }else{
-      len = sqlite3VdbeSerialTypeLen(aType[p2]);
-      sqlite3VdbeMemMove(&sMem, pDest);
-      rc = sqlite3VdbeMemFromBtree(pCrsr, aOffset[p2], len, pC->isIndex, &sMem);
-      if( rc!=SQLITE_OK ){
-        goto op_column_out;
-      }
-      zData = sMem.z;
-      sqlite3VdbeSerialGet((u8*)zData, aType[p2], pDest);
-    }
-    pDest->enc = encoding;
-  }else{
-    if( pOp->p4type==P4_MEM ){
-      sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
-    }else{
-      assert( pDest->flags&MEM_Null );
+  /* We have successfully halted and closed the VM.  Record this fact. */
+  if( p->pc>=0 ){
+    db->activeVdbeCnt--;
+    if( !p->readOnly ){
+      db->writeVdbeCnt--;
     }
+    assert( db->activeVdbeCnt>=db->writeVdbeCnt );
+  }
+  p->magic = VDBE_MAGIC_HALT;
+  checkActiveVdbeCnt(db);
+  if( p->db->mallocFailed ){
+    p->rc = SQLITE_NOMEM;
   }
 
-  /* If we dynamically allocated space to hold the data (in the
-  ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
-  ** dynamically allocated space over to the pDest structure.
-  ** This prevents a memory copy.
+  /* If the auto-commit flag is set to true, then any locks that were held
+  ** by connection db have now been released. Call sqlite3ConnectionUnlocked() 
+  ** to invoke any required unlock-notify callbacks.
   */
-  if( sMem.zMalloc ){
-    assert( sMem.z==sMem.zMalloc );
-    assert( !(pDest->flags & MEM_Dyn) );
-    assert( !(pDest->flags & (MEM_Blob|MEM_Str)) || pDest->z==sMem.z );
-    pDest->flags &= ~(MEM_Ephem|MEM_Static);
-    pDest->flags |= MEM_Term;
-    pDest->z = sMem.z;
-    pDest->zMalloc = sMem.zMalloc;
+  if( db->autoCommit ){
+    sqlite3ConnectionUnlocked(db);
   }
 
-  rc = sqlite3VdbeMemMakeWriteable(pDest);
-
-op_column_out:
-  UPDATE_MAX_BLOBSIZE(pDest);
-  REGISTER_TRACE(pOp->p3, pDest);
-  break;
+  assert( db->activeVdbeCnt>0 || db->autoCommit==0 || db->nStatement==0 );
+  return SQLITE_OK;
 }
 
-/* Opcode: Affinity P1 P2 * P4 *
-**
-** Apply affinities to a range of P2 registers starting with P1.
-**
-** P4 is a string that is P2 characters long. The nth character of the
-** string indicates the column affinity that should be used for the nth
-** memory cell in the range.
-*/
-case OP_Affinity: {
-  char *zAffinity = pOp->p4.z;
-  Mem *pData0 = &p->aMem[pOp->p1];
-  Mem *pLast = &pData0[pOp->p2-1];
-  Mem *pRec;
 
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    ExpandBlob(pRec);
-    applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
-  }
-  break;
+/*
+** Each VDBE holds the result of the most recent sqlite3_step() call
+** in p->rc.  This routine sets that result back to SQLITE_OK.
+*/
+SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe *p){
+  p->rc = SQLITE_OK;
 }
 
-/* Opcode: MakeRecord P1 P2 P3 P4 *
-**
-** Convert P2 registers beginning with P1 into a single entry
-** suitable for use as a data record in a database table or as a key
-** in an index.  The details of the format are irrelavant as long as
-** the OP_Column opcode can decode the record later.
-** Refer to source code comments for the details of the record
-** format.
-**
-** P4 may be a string that is P2 characters long.  The nth character of the
-** string indicates the column affinity that should be used for the nth
-** field of the index key.
+/*
+** Clean up a VDBE after execution but do not delete the VDBE just yet.
+** Write any error messages into *pzErrMsg.  Return the result code.
 **
-** The mapping from character to affinity is given by the SQLITE_AFF_
-** macros defined in sqliteInt.h.
+** After this routine is run, the VDBE should be ready to be executed
+** again.
 **
-** If P4 is NULL then all index fields have the affinity NONE.
+** To look at it another way, this routine resets the state of the
+** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
+** VDBE_MAGIC_INIT.
 */
-case OP_MakeRecord: {
-  /* Assuming the record contains N fields, the record format looks
-  ** like this:
-  **
-  ** ------------------------------------------------------------------------
-  ** | hdr-size | type 0 | type 1 | ... | type N-1 | data0 | ... | data N-1 | 
-  ** ------------------------------------------------------------------------
-  **
-  ** Data(0) is taken from register P1.  Data(1) comes from register P1+1
-  ** and so froth.
-  **
-  ** Each type field is a varint representing the serial type of the 
-  ** corresponding data element (see sqlite3VdbeSerialType()). The
-  ** hdr-size field is also a varint which is the offset from the beginning
-  ** of the record to data0.
-  */
-  u8 *zNewRecord;        /* A buffer to hold the data for the new record */
-  Mem *pRec;             /* The new record */
-  u64 nData = 0;         /* Number of bytes of data space */
-  int nHdr = 0;          /* Number of bytes of header space */
-  u64 nByte = 0;         /* Data space required for this record */
-  int nZero = 0;         /* Number of zero bytes at the end of the record */
-  int nVarint;           /* Number of bytes in a varint */
-  u32 serial_type;       /* Type field */
-  Mem *pData0;           /* First field to be combined into the record */
-  Mem *pLast;            /* Last field of the record */
-  int nField;            /* Number of fields in the record */
-  char *zAffinity;       /* The affinity string for the record */
-  int file_format;       /* File format to use for encoding */
-  int i;                 /* Space used in zNewRecord[] */
+SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe *p){
+  sqlite3 *db;
+  db = p->db;
 
-  nField = pOp->p1;
-  zAffinity = pOp->p4.z;
-  assert( nField>0 && pOp->p2>0 && pOp->p2+nField<=p->nMem );
-  pData0 = &p->aMem[nField];
-  nField = pOp->p2;
-  pLast = &pData0[nField-1];
-  file_format = p->minWriteFileFormat;
+  /* If the VM did not run to completion or if it encountered an
+  ** error, then it might not have been halted properly.  So halt
+  ** it now.
+  */
+  (void)sqlite3SafetyOn(db);
+  sqlite3VdbeHalt(p);
+  (void)sqlite3SafetyOff(db);
 
-  /* Loop through the elements that will make up the record to figure
-  ** out how much space is required for the new record.
+  /* If the VDBE has be run even partially, then transfer the error code
+  ** and error message from the VDBE into the main database structure.  But
+  ** if the VDBE has just been set to run but has not actually executed any
+  ** instructions yet, leave the main database error information unchanged.
   */
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    int len;
-    if( zAffinity ){
-      applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
-    }
-    if( pRec->flags&MEM_Zero && pRec->n>0 ){
-      sqlite3VdbeMemExpandBlob(pRec);
-    }
-    serial_type = sqlite3VdbeSerialType(pRec, file_format);
-    len = sqlite3VdbeSerialTypeLen(serial_type);
-    nData += len;
-    nHdr += sqlite3VarintLen(serial_type);
-    if( pRec->flags & MEM_Zero ){
-      /* Only pure zero-filled BLOBs can be input to this Opcode.
-      ** We do not allow blobs with a prefix and a zero-filled tail. */
-      nZero += pRec->u.i;
-    }else if( len ){
-      nZero = 0;
+  if( p->pc>=0 ){
+    if( p->zErrMsg ){
+      sqlite3BeginBenignMalloc();
+      sqlite3ValueSetStr(db->pErr,-1,p->zErrMsg,SQLITE_UTF8,SQLITE_TRANSIENT);
+      sqlite3EndBenignMalloc();
+      db->errCode = p->rc;
+      sqlite3DbFree(db, p->zErrMsg);
+      p->zErrMsg = 0;
+    }else if( p->rc ){
+      sqlite3Error(db, p->rc, 0);
+    }else{
+      sqlite3Error(db, SQLITE_OK, 0);
     }
+  }else if( p->rc && p->expired ){
+    /* The expired flag was set on the VDBE before the first call
+    ** to sqlite3_step(). For consistency (since sqlite3_step() was
+    ** called), set the database error in this case as well.
+    */
+    sqlite3Error(db, p->rc, 0);
+    sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = 0;
   }
 
-  /* Add the initial header varint and total the size */
-  nHdr += nVarint = sqlite3VarintLen(nHdr);
-  if( nVarint<sqlite3VarintLen(nHdr) ){
-    nHdr++;
-  }
-  nByte = nHdr+nData-nZero;
-  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-
-  /* Make sure the output register has a buffer large enough to store 
-  ** the new record. The output register (pOp->p3) is not allowed to
-  ** be one of the input registers (because the following call to
-  ** sqlite3VdbeMemGrow() could clobber the value before it is used).
+  /* Reclaim all memory used by the VDBE
   */
-  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
-  pOut = &p->aMem[pOp->p3];
-  if( sqlite3VdbeMemGrow(pOut, nByte, 0) ){
-    goto no_mem;
-  }
-  zNewRecord = (u8 *)pOut->z;
+  Cleanup(p);
 
-  /* Write the record */
-  i = putVarint32(zNewRecord, nHdr);
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    serial_type = sqlite3VdbeSerialType(pRec, file_format);
-    i += putVarint32(&zNewRecord[i], serial_type);      /* serial type */
-  }
-  for(pRec=pData0; pRec<=pLast; pRec++){  /* serial data */
-    i += sqlite3VdbeSerialPut(&zNewRecord[i], nByte-i, pRec, file_format);
+  /* Save profiling information from this VDBE run.
+  */
+#ifdef VDBE_PROFILE
+  {
+    FILE *out = fopen("vdbe_profile.out", "a");
+    if( out ){
+      int i;
+      fprintf(out, "---- ");
+      for(i=0; i<p->nOp; i++){
+        fprintf(out, "%02x", p->aOp[i].opcode);
+      }
+      fprintf(out, "\n");
+      for(i=0; i<p->nOp; i++){
+        fprintf(out, "%6d %10lld %8lld ",
+           p->aOp[i].cnt,
+           p->aOp[i].cycles,
+           p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
+        );
+        sqlite3VdbePrintOp(out, i, &p->aOp[i]);
+      }
+      fclose(out);
+    }
   }
-  assert( i==nByte );
-
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut->n = nByte;
-  pOut->flags = MEM_Blob | MEM_Dyn;
-  pOut->xDel = 0;
-  if( nZero ){
-    pOut->u.i = nZero;
-    pOut->flags |= MEM_Zero;
+#endif
+  p->magic = VDBE_MAGIC_INIT;
+  return p->rc & db->errMask;
+}
+ 
+/*
+** Clean up and delete a VDBE after execution.  Return an integer which is
+** the result code.  Write any error message text into *pzErrMsg.
+*/
+SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe *p){
+  int rc = SQLITE_OK;
+  if( p->magic==VDBE_MAGIC_RUN || p->magic==VDBE_MAGIC_HALT ){
+    rc = sqlite3VdbeReset(p);
+    assert( (rc & p->db->errMask)==rc );
   }
-  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever converted to text */
-  REGISTER_TRACE(pOp->p3, pOut);
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
+  sqlite3VdbeDelete(p);
+  return rc;
 }
 
-/* Opcode: Statement P1 * * * *
-**
-** Begin an individual statement transaction which is part of a larger
-** transaction.  This is needed so that the statement
-** can be rolled back after an error without having to roll back the
-** entire transaction.  The statement transaction will automatically
-** commit when the VDBE halts.
-**
-** If the database connection is currently in autocommit mode (that 
-** is to say, if it is in between BEGIN and COMMIT)
-** and if there are no other active statements on the same database
-** connection, then this operation is a no-op.  No statement transaction
-** is needed since any error can use the normal ROLLBACK process to
-** undo changes.
-**
-** If a statement transaction is started, then a statement journal file
-** will be allocated and initialized.
-**
-** The statement is begun on the database file with index P1.  The main
-** database file has an index of 0 and the file used for temporary tables
-** has an index of 1.
+/*
+** Call the destructor for each auxdata entry in pVdbeFunc for which
+** the corresponding bit in mask is clear.  Auxdata entries beyond 31
+** are always destroyed.  To destroy all auxdata entries, call this
+** routine with mask==0.
 */
-case OP_Statement: {
-  if( db->autoCommit==0 || db->activeVdbeCnt>1 ){
-    int i = pOp->p1;
-    Btree *pBt;
-    assert( i>=0 && i<db->nDb );
-    assert( db->aDb[i].pBt!=0 );
-    pBt = db->aDb[i].pBt;
-    assert( sqlite3BtreeIsInTrans(pBt) );
-    assert( (p->btreeMask & (1<<i))!=0 );
-    if( !sqlite3BtreeIsInStmt(pBt) ){
-      rc = sqlite3BtreeBeginStmt(pBt);
-      p->openedStatement = 1;
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
+  int i;
+  for(i=0; i<pVdbeFunc->nAux; i++){
+    struct AuxData *pAux = &pVdbeFunc->apAux[i];
+    if( (i>31 || !(mask&(((u32)1)<<i))) && pAux->pAux ){
+      if( pAux->xDelete ){
+        pAux->xDelete(pAux->pAux);
+      }
+      pAux->pAux = 0;
     }
   }
-  break;
 }
 
-/* Opcode: AutoCommit P1 P2 * * *
-**
-** Set the database auto-commit flag to P1 (1 or 0). If P2 is true, roll
-** back any currently active btree transactions. If there are any active
-** VMs (apart from this one), then the COMMIT or ROLLBACK statement fails.
-**
-** This instruction causes the VM to halt.
+/*
+** Delete an entire VDBE.
 */
-case OP_AutoCommit: {
-  u8 i = pOp->p1;
-  u8 rollback = pOp->p2;
-
-  assert( i==1 || i==0 );
-  assert( i==1 || rollback==0 );
-
-  assert( db->activeVdbeCnt>0 );  /* At least this one VM is active */
+SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
+  sqlite3 *db;
 
-  if( db->activeVdbeCnt>1 && i && !db->autoCommit ){
-    /* If this instruction implements a COMMIT or ROLLBACK, other VMs are
-    ** still running, and a transaction is active, return an error indicating
-    ** that the other VMs must complete first. 
-    */
-    sqlite3SetString(&p->zErrMsg, "cannot ", rollback?"rollback":"commit", 
-        " transaction - SQL statements in progress", (char*)0);
-    rc = SQLITE_ERROR;
-  }else if( i!=db->autoCommit ){
-    if( pOp->p2 ){
-      assert( i==1 );
-      sqlite3RollbackAll(db);
-      db->autoCommit = 1;
-    }else{
-      db->autoCommit = i;
-      if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
-        p->pc = pc;
-        db->autoCommit = 1-i;
-        p->rc = rc = SQLITE_BUSY;
-        goto vdbe_return;
-      }
-    }
-    if( p->rc==SQLITE_OK ){
-      rc = SQLITE_DONE;
-    }else{
-      rc = SQLITE_ERROR;
-    }
-    goto vdbe_return;
+  if( NEVER(p==0) ) return;
+  db = p->db;
+  if( p->pPrev ){
+    p->pPrev->pNext = p->pNext;
   }else{
-    sqlite3SetString(&p->zErrMsg,
-        (!i)?"cannot start a transaction within a transaction":(
-        (rollback)?"cannot rollback - no transaction is active":
-                   "cannot commit - no transaction is active"), (char*)0);
-         
-    rc = SQLITE_ERROR;
+    assert( db->pVdbe==p );
+    db->pVdbe = p->pNext;
   }
-  break;
+  if( p->pNext ){
+    p->pNext->pPrev = p->pPrev;
+  }
+  releaseMemArray(p->aVar, p->nVar);
+  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
+  vdbeFreeOpArray(db, p->aOp, p->nOp);
+  sqlite3DbFree(db, p->aLabel);
+  sqlite3DbFree(db, p->aColName);
+  sqlite3DbFree(db, p->zSql);
+  p->magic = VDBE_MAGIC_DEAD;
+  sqlite3DbFree(db, p->pFree);
+  sqlite3DbFree(db, p);
 }
 
-/* Opcode: Transaction P1 P2 * * *
-**
-** Begin a transaction.  The transaction ends when a Commit or Rollback
-** opcode is encountered.  Depending on the ON CONFLICT setting, the
-** transaction might also be rolled back if an error is encountered.
-**
-** P1 is the index of the database file on which the transaction is
-** started.  Index 0 is the main database file and index 1 is the
-** file used for temporary tables.  Indices of 2 or more are used for
-** attached databases.
+/*
+** Make sure the cursor p is ready to read or write the row to which it
+** was last positioned.  Return an error code if an OOM fault or I/O error
+** prevents us from positioning the cursor to its correct position.
 **
-** If P2 is non-zero, then a write-transaction is started.  A RESERVED lock is
-** obtained on the database file when a write-transaction is started.  No
-** other process can start another write transaction while this transaction is
-** underway.  Starting a write transaction also creates a rollback journal. A
-** write transaction must be started before any changes can be made to the
-** database.  If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
-** on the file.
+** If a MoveTo operation is pending on the given cursor, then do that
+** MoveTo now.  If no move is pending, check to see if the row has been
+** deleted out from under the cursor and if it has, mark the row as
+** a NULL row.
 **
-** If P2 is zero, then a read-lock is obtained on the database file.
+** If the cursor is already pointing to the correct row and that row has
+** not been deleted out from under the cursor, then this routine is a no-op.
 */
-case OP_Transaction: {
-  int i = pOp->p1;
-  Btree *pBt;
-
-  assert( i>=0 && i<db->nDb );
-  assert( (p->btreeMask & (1<<i))!=0 );
-  pBt = db->aDb[i].pBt;
-
-  if( pBt ){
-    rc = sqlite3BtreeBeginTrans(pBt, pOp->p2);
-    if( rc==SQLITE_BUSY ){
-      p->pc = pc;
-      p->rc = rc = SQLITE_BUSY;
-      goto vdbe_return;
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor *p){
+  if( p->deferredMoveto ){
+    int res, rc;
+#ifdef SQLITE_TEST
+    extern int sqlite3_search_count;
+#endif
+    assert( p->isTable );
+    rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
+    if( rc ) return rc;
+    p->lastRowid = p->movetoTarget;
+    p->rowidIsValid = ALWAYS(res==0) ?1:0;
+    if( NEVER(res<0) ){
+      rc = sqlite3BtreeNext(p->pCursor, &res);
+      if( rc ) return rc;
     }
-    if( rc!=SQLITE_OK && rc!=SQLITE_READONLY /* && rc!=SQLITE_BUSY */ ){
-      goto abort_due_to_error;
+#ifdef SQLITE_TEST
+    sqlite3_search_count++;
+#endif
+    p->deferredMoveto = 0;
+    p->cacheStatus = CACHE_STALE;
+  }else if( ALWAYS(p->pCursor) ){
+    int hasMoved;
+    int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
+    if( rc ) return rc;
+    if( hasMoved ){
+      p->cacheStatus = CACHE_STALE;
+      p->nullRow = 1;
     }
   }
-  break;
+  return SQLITE_OK;
 }
 
-/* Opcode: ReadCookie P1 P2 P3 * *
+/*
+** The following functions:
 **
-** Read cookie number P3 from database P1 and write it into register P2.
-** P3==0 is the schema version.  P3==1 is the database format.
-** P3==2 is the recommended pager cache size, and so forth.  P1==0 is
-** the main database file and P1==1 is the database file used to store
-** temporary tables.
+** sqlite3VdbeSerialType()
+** sqlite3VdbeSerialTypeLen()
+** sqlite3VdbeSerialLen()
+** sqlite3VdbeSerialPut()
+** sqlite3VdbeSerialGet()
 **
-** If P1 is negative, then this is a request to read the size of a
-** databases free-list. P3 must be set to 1 in this case. The actual
-** database accessed is ((P1+1)*-1). For example, a P1 parameter of -1
-** corresponds to database 0 ("main"), a P1 of -2 is database 1 ("temp").
+** encapsulate the code that serializes values for storage in SQLite
+** data and index records. Each serialized value consists of a
+** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
+** integer, stored as a varint.
 **
-** There must be a read-lock on the database (either a transaction
-** must be started or there must be an open cursor) before
-** executing this instruction.
-*/
-case OP_ReadCookie: {               /* out2-prerelease */
-  int iMeta;
-  int iDb = pOp->p1;
-  int iCookie = pOp->p3;
-
-  assert( pOp->p3<SQLITE_N_BTREE_META );
-  if( iDb<0 ){
-    iDb = (-1*(iDb+1));
-    iCookie *= -1;
-  }
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( db->aDb[iDb].pBt!=0 );
-  assert( (p->btreeMask & (1<<iDb))!=0 );
-  /* The indexing of meta values at the schema layer is off by one from
-  ** the indexing in the btree layer.  The btree considers meta[0] to
-  ** be the number of free pages in the database (a read-only value)
-  ** and meta[1] to be the schema cookie.  The schema layer considers
-  ** meta[1] to be the schema cookie.  So we have to shift the index
-  ** by one in the following statement.
-  */
-  rc = sqlite3BtreeGetMeta(db->aDb[iDb].pBt, 1 + iCookie, (u32 *)&iMeta);
-  pOut->u.i = iMeta;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-/* Opcode: SetCookie P1 P2 P3 * *
+** In an SQLite index record, the serial type is stored directly before
+** the blob of data that it corresponds to. In a table record, all serial
+** types are stored at the start of the record, and the blobs of data at
+** the end. Hence these functions allow the caller to handle the
+** serial-type and data blob seperately.
 **
-** Write the content of register P3 (interpreted as an integer)
-** into cookie number P2 of database P1.
-** P2==0 is the schema version.  P2==1 is the database format.
-** P2==2 is the recommended pager cache size, and so forth.  P1==0 is
-** the main database file and P1==1 is the database file used to store
-** temporary tables.
+** The following table describes the various storage classes for data:
 **
-** A transaction must be started before executing this opcode.
+**   serial type        bytes of data      type
+**   --------------     ---------------    ---------------
+**      0                     0            NULL
+**      1                     1            signed integer
+**      2                     2            signed integer
+**      3                     3            signed integer
+**      4                     4            signed integer
+**      5                     6            signed integer
+**      6                     8            signed integer
+**      7                     8            IEEE float
+**      8                     0            Integer constant 0
+**      9                     0            Integer constant 1
+**     10,11                               reserved for expansion
+**    N>=12 and even       (N-12)/2        BLOB
+**    N>=13 and odd        (N-13)/2        text
+**
+** The 8 and 9 types were added in 3.3.0, file format 4.  Prior versions
+** of SQLite will not understand those serial types.
 */
-case OP_SetCookie: {       /* in3 */
-  Db *pDb;
-  assert( pOp->p2<SQLITE_N_BTREE_META );
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pDb = &db->aDb[pOp->p1];
-  assert( pDb->pBt!=0 );
-  sqlite3VdbeMemIntegerify(pIn3);
-  /* See note about index shifting on OP_ReadCookie */
-  rc = sqlite3BtreeUpdateMeta(pDb->pBt, 1+pOp->p2, (int)pIn3->u.i);
-  if( pOp->p2==0 ){
-    /* When the schema cookie changes, record the new cookie internally */
-    pDb->pSchema->schema_cookie = pIn3->u.i;
-    db->flags |= SQLITE_InternChanges;
-  }else if( pOp->p2==1 ){
-    /* Record changes in the file format */
-    pDb->pSchema->file_format = pIn3->u.i;
+
+/*
+** Return the serial-type for the value stored in pMem.
+*/
+SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
+  int flags = pMem->flags;
+  int n;
+
+  if( flags&MEM_Null ){
+    return 0;
   }
-  if( pOp->p1==1 ){
-    /* Invalidate all prepared statements whenever the TEMP database
-    ** schema is changed.  Ticket #1644 */
-    sqlite3ExpirePreparedStatements(db);
+  if( flags&MEM_Int ){
+    /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
+#   define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
+    i64 i = pMem->u.i;
+    u64 u;
+    if( file_format>=4 && (i&1)==i ){
+      return 8+(u32)i;
+    }
+    u = i<0 ? -i : i;
+    if( u<=127 ) return 1;
+    if( u<=32767 ) return 2;
+    if( u<=8388607 ) return 3;
+    if( u<=2147483647 ) return 4;
+    if( u<=MAX_6BYTE ) return 5;
+    return 6;
   }
-  break;
+  if( flags&MEM_Real ){
+    return 7;
+  }
+  assert( pMem->db->mallocFailed || flags&(MEM_Str|MEM_Blob) );
+  n = pMem->n;
+  if( flags & MEM_Zero ){
+    n += pMem->u.nZero;
+  }
+  assert( n>=0 );
+  return ((n*2) + 12 + ((flags&MEM_Str)!=0));
 }
 
-/* Opcode: VerifyCookie P1 P2 *
-**
-** Check the value of global database parameter number 0 (the
-** schema version) and make sure it is equal to P2.  
-** P1 is the database number which is 0 for the main database file
-** and 1 for the file holding temporary tables and some higher number
-** for auxiliary databases.
-**
-** The cookie changes its value whenever the database schema changes.
-** This operation is used to detect when that the cookie has changed
-** and that the current process needs to reread the schema.
-**
-** Either a transaction needs to have been started or an OP_Open needs
-** to be executed (to establish a read lock) before this opcode is
-** invoked.
+/*
+** Return the length of the data corresponding to the supplied serial-type.
 */
-case OP_VerifyCookie: {
-  int iMeta;
-  Btree *pBt;
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pBt = db->aDb[pOp->p1].pBt;
-  if( pBt ){
-    rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&iMeta);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32 serial_type){
+  if( serial_type>=12 ){
+    return (serial_type-12)/2;
   }else{
-    rc = SQLITE_OK;
-    iMeta = 0;
-  }
-  if( rc==SQLITE_OK && iMeta!=pOp->p2 ){
-    sqlite3_free(p->zErrMsg);
-    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
-    /* If the schema-cookie from the database file matches the cookie 
-    ** stored with the in-memory representation of the schema, do
-    ** not reload the schema from the database file.
-    **
-    ** If virtual-tables are in use, this is not just an optimisation.
-    ** Often, v-tables store their data in other SQLite tables, which
-    ** are queried from within xNext() and other v-table methods using
-    ** prepared queries. If such a query is out-of-date, we do not want to
-    ** discard the database schema, as the user code implementing the
-    ** v-table would have to be ready for the sqlite3_vtab structure itself
-    ** to be invalidated whenever sqlite3_step() is called from within 
-    ** a v-table method.
-    */
-    if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
-      sqlite3ResetInternalSchema(db, pOp->p1);
-    }
-
-    sqlite3ExpirePreparedStatements(db);
-    rc = SQLITE_SCHEMA;
+    static const u8 aSize[] = { 0, 1, 2, 3, 4, 6, 8, 8, 0, 0, 0, 0 };
+    return aSize[serial_type];
   }
-  break;
 }
 
-/* Opcode: OpenRead P1 P2 P3 P4 P5
-**
-** Open a read-only cursor for the database table whose root page is
-** P2 in a database file.  The database file is determined by P3. 
-** P3==0 means the main database, P3==1 means the database used for 
-** temporary tables, and P3>1 means used the corresponding attached
-** database.  Give the new cursor an identifier of P1.  The P1
-** values need not be contiguous but all P1 values should be small integers.
-** It is an error for P1 to be negative.
+/*
+** If we are on an architecture with mixed-endian floating 
+** points (ex: ARM7) then swap the lower 4 bytes with the 
+** upper 4 bytes.  Return the result.
 **
-** If P5!=0 then use the content of register P2 as the root page, not
-** the value of P2 itself.
+** For most architectures, this is a no-op.
 **
-** There will be a read lock on the database whenever there is an
-** open cursor.  If the database was unlocked prior to this instruction
-** then a read lock is acquired as part of this instruction.  A read
-** lock allows other processes to read the database but prohibits
-** any other process from modifying the database.  The read lock is
-** released when all cursors are closed.  If this instruction attempts
-** to get a read lock but fails, the script terminates with an
-** SQLITE_BUSY error code.
+** (later):  It is reported to me that the mixed-endian problem
+** on ARM7 is an issue with GCC, not with the ARM7 chip.  It seems
+** that early versions of GCC stored the two words of a 64-bit
+** float in the wrong order.  And that error has been propagated
+** ever since.  The blame is not necessarily with GCC, though.
+** GCC might have just copying the problem from a prior compiler.
+** I am also told that newer versions of GCC that follow a different
+** ABI get the byte order right.
 **
-** The P4 value is a pointer to a KeyInfo structure that defines the
-** content and collating sequence of indices.  P4 is NULL for cursors
-** that are not pointing to indices.
+** Developers using SQLite on an ARM7 should compile and run their
+** application using -DSQLITE_DEBUG=1 at least once.  With DEBUG
+** enabled, some asserts below will ensure that the byte order of
+** floating point values is correct.
 **
-** See also OpenWrite.
+** (2007-08-30)  Frank van Vugt has studied this problem closely
+** and has send his findings to the SQLite developers.  Frank
+** writes that some Linux kernels offer floating point hardware
+** emulation that uses only 32-bit mantissas instead of a full 
+** 48-bits as required by the IEEE standard.  (This is the
+** CONFIG_FPE_FASTFPE option.)  On such systems, floating point
+** byte swapping becomes very complicated.  To avoid problems,
+** the necessary byte swapping is carried out using a 64-bit integer
+** rather than a 64-bit float.  Frank assures us that the code here
+** works for him.  We, the developers, have no way to independently
+** verify this, but Frank seems to know what he is talking about
+** so we trust him.
 */
-/* Opcode: OpenWrite P1 P2 P3 P4 P5
-**
-** Open a read/write cursor named P1 on the table or index whose root
-** page is P2.  Or if P5!=0 use the content of register P2 to find the
-** root page.
-**
-** The P4 value is a pointer to a KeyInfo structure that defines the
-** content and collating sequence of indices.  P4 is NULL for cursors
-** that are not pointing to indices.
+#ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
+static u64 floatSwap(u64 in){
+  union {
+    u64 r;
+    u32 i[2];
+  } u;
+  u32 t;
+
+  u.r = in;
+  t = u.i[0];
+  u.i[0] = u.i[1];
+  u.i[1] = t;
+  return u.r;
+}
+# define swapMixedEndianFloat(X)  X = floatSwap(X)
+#else
+# define swapMixedEndianFloat(X)
+#endif
+
+/*
+** Write the serialized data blob for the value stored in pMem into 
+** buf. It is assumed that the caller has allocated sufficient space.
+** Return the number of bytes written.
 **
-** This instruction works just like OpenRead except that it opens the cursor
-** in read/write mode.  For a given table, there can be one or more read-only
-** cursors or a single read/write cursor but not both.
+** nBuf is the amount of space left in buf[].  nBuf must always be
+** large enough to hold the entire field.  Except, if the field is
+** a blob with a zero-filled tail, then buf[] might be just the right
+** size to hold everything except for the zero-filled tail.  If buf[]
+** is only big enough to hold the non-zero prefix, then only write that
+** prefix into buf[].  But if buf[] is large enough to hold both the
+** prefix and the tail then write the prefix and set the tail to all
+** zeros.
 **
-** See also OpenRead.
-*/
-case OP_OpenRead:
-case OP_OpenWrite: {
-  int i = pOp->p1;
-  int p2 = pOp->p2;
-  int iDb = pOp->p3;
-  int wrFlag;
-  Btree *pX;
-  Cursor *pCur;
-  Db *pDb;
-  
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( (p->btreeMask & (1<<iDb))!=0 );
-  pDb = &db->aDb[iDb];
-  pX = pDb->pBt;
-  assert( pX!=0 );
-  if( pOp->opcode==OP_OpenWrite ){
-    wrFlag = 1;
-    if( pDb->pSchema->file_format < p->minWriteFileFormat ){
-      p->minWriteFileFormat = pDb->pSchema->file_format;
+** Return the number of bytes actually written into buf[].  The number
+** of bytes in the zero-filled tail is included in the return value only
+** if those bytes were zeroed in buf[].
+*/ 
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(u8 *buf, int nBuf, Mem *pMem, int file_format){
+  u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
+  u32 len;
+
+  /* Integer and Real */
+  if( serial_type<=7 && serial_type>0 ){
+    u64 v;
+    u32 i;
+    if( serial_type==7 ){
+      assert( sizeof(v)==sizeof(pMem->r) );
+      memcpy(&v, &pMem->r, sizeof(v));
+      swapMixedEndianFloat(v);
+    }else{
+      v = pMem->u.i;
     }
-  }else{
-    wrFlag = 0;
+    len = i = sqlite3VdbeSerialTypeLen(serial_type);
+    assert( len<=(u32)nBuf );
+    while( i-- ){
+      buf[i] = (u8)(v&0xFF);
+      v >>= 8;
+    }
+    return len;
   }
-  if( pOp->p5 ){
-    assert( p2>0 );
-    assert( p2<=p->nMem );
-    pIn2 = &p->aMem[p2];
-    sqlite3VdbeMemIntegerify(pIn2);
-    p2 = pIn2->u.i;
-    assert( p2>=2 );
-  }
-  assert( i>=0 );
-  pCur = allocateCursor(p, i, &pOp[-1], iDb, 1);
-  if( pCur==0 ) goto no_mem;
-  pCur->nullRow = 1;
-  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pOp->p4.p, pCur->pCursor);
-  if( pOp->p4type==P4_KEYINFO ){
-    pCur->pKeyInfo = pOp->p4.pKeyInfo;
-    pCur->pIncrKey = &pCur->pKeyInfo->incrKey;
-    pCur->pKeyInfo->enc = ENC(p->db);
-  }else{
-    pCur->pKeyInfo = 0;
-    pCur->pIncrKey = &pCur->bogusIncrKey;
+
+  /* String or blob */
+  if( serial_type>=12 ){
+    assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
+             == (int)sqlite3VdbeSerialTypeLen(serial_type) );
+    assert( pMem->n<=nBuf );
+    len = pMem->n;
+    memcpy(buf, pMem->z, len);
+    if( pMem->flags & MEM_Zero ){
+      len += pMem->u.nZero;
+      assert( nBuf>=0 );
+      if( len > (u32)nBuf ){
+        len = (u32)nBuf;
+      }
+      memset(&buf[pMem->n], 0, len-pMem->n);
+    }
+    return len;
   }
-  switch( rc ){
-    case SQLITE_BUSY: {
-      p->pc = pc;
-      p->rc = rc = SQLITE_BUSY;
-      goto vdbe_return;
+
+  /* NULL or constants 0 or 1 */
+  return 0;
+}
+
+/*
+** Deserialize the data blob pointed to by buf as serial type serial_type
+** and store the result in pMem.  Return the number of bytes read.
+*/ 
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(
+  const unsigned char *buf,     /* Buffer to deserialize from */
+  u32 serial_type,              /* Serial type to deserialize */
+  Mem *pMem                     /* Memory cell to write value into */
+){
+  switch( serial_type ){
+    case 10:   /* Reserved for future use */
+    case 11:   /* Reserved for future use */
+    case 0: {  /* NULL */
+      pMem->flags = MEM_Null;
+      break;
     }
-    case SQLITE_OK: {
-      int flags = sqlite3BtreeFlags(pCur->pCursor);
-      /* Sanity checking.  Only the lower four bits of the flags byte should
-      ** be used.  Bit 3 (mask 0x08) is unpreditable.  The lower 3 bits
-      ** (mask 0x07) should be either 5 (intkey+leafdata for tables) or
-      ** 2 (zerodata for indices).  If these conditions are not met it can
-      ** only mean that we are dealing with a corrupt database file
-      */
-      if( (flags & 0xf0)!=0 || ((flags & 0x07)!=5 && (flags & 0x07)!=2) ){
-        rc = SQLITE_CORRUPT_BKPT;
-        goto abort_due_to_error;
-      }
-      pCur->isTable = (flags & BTREE_INTKEY)!=0;
-      pCur->isIndex = (flags & BTREE_ZERODATA)!=0;
-      /* If P4==0 it means we are expected to open a table.  If P4!=0 then
-      ** we expect to be opening an index.  If this is not what happened,
-      ** then the database is corrupt
+    case 1: { /* 1-byte signed integer */
+      pMem->u.i = (signed char)buf[0];
+      pMem->flags = MEM_Int;
+      return 1;
+    }
+    case 2: { /* 2-byte signed integer */
+      pMem->u.i = (((signed char)buf[0])<<8) | buf[1];
+      pMem->flags = MEM_Int;
+      return 2;
+    }
+    case 3: { /* 3-byte signed integer */
+      pMem->u.i = (((signed char)buf[0])<<16) | (buf[1]<<8) | buf[2];
+      pMem->flags = MEM_Int;
+      return 3;
+    }
+    case 4: { /* 4-byte signed integer */
+      pMem->u.i = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
+      pMem->flags = MEM_Int;
+      return 4;
+    }
+    case 5: { /* 6-byte signed integer */
+      u64 x = (((signed char)buf[0])<<8) | buf[1];
+      u32 y = (buf[2]<<24) | (buf[3]<<16) | (buf[4]<<8) | buf[5];
+      x = (x<<32) | y;
+      pMem->u.i = *(i64*)&x;
+      pMem->flags = MEM_Int;
+      return 6;
+    }
+    case 6:   /* 8-byte signed integer */
+    case 7: { /* IEEE floating point */
+      u64 x;
+      u32 y;
+#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
+      /* Verify that integers and floating point values use the same
+      ** byte order.  Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
+      ** defined that 64-bit floating point values really are mixed
+      ** endian.
       */
-      if( (pCur->isTable && pOp->p4type==P4_KEYINFO)
-       || (pCur->isIndex && pOp->p4type!=P4_KEYINFO) ){
-        rc = SQLITE_CORRUPT_BKPT;
-        goto abort_due_to_error;
+      static const u64 t1 = ((u64)0x3ff00000)<<32;
+      static const double r1 = 1.0;
+      u64 t2 = t1;
+      swapMixedEndianFloat(t2);
+      assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
+#endif
+
+      x = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
+      y = (buf[4]<<24) | (buf[5]<<16) | (buf[6]<<8) | buf[7];
+      x = (x<<32) | y;
+      if( serial_type==6 ){
+        pMem->u.i = *(i64*)&x;
+        pMem->flags = MEM_Int;
+      }else{
+        assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
+        swapMixedEndianFloat(x);
+        memcpy(&pMem->r, &x, sizeof(x));
+        pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
       }
-      break;
+      return 8;
     }
-    case SQLITE_EMPTY: {
-      pCur->isTable = pOp->p4type!=P4_KEYINFO;
-      pCur->isIndex = !pCur->isTable;
-      pCur->pCursor = 0;
-      rc = SQLITE_OK;
-      break;
+    case 8:    /* Integer 0 */
+    case 9: {  /* Integer 1 */
+      pMem->u.i = serial_type-8;
+      pMem->flags = MEM_Int;
+      return 0;
     }
     default: {
-      goto abort_due_to_error;
+      u32 len = (serial_type-12)/2;
+      pMem->z = (char *)buf;
+      pMem->n = len;
+      pMem->xDel = 0;
+      if( serial_type&0x01 ){
+        pMem->flags = MEM_Str | MEM_Ephem;
+      }else{
+        pMem->flags = MEM_Blob | MEM_Ephem;
+      }
+      return len;
     }
   }
-  break;
+  return 0;
 }
 
-/* Opcode: OpenEphemeral P1 P2 * P4 *
-**
-** Open a new cursor P1 to a transient table.
-** The cursor is always opened read/write even if 
-** the main database is read-only.  The transient or virtual
-** table is deleted automatically when the cursor is closed.
+
+/*
+** Given the nKey-byte encoding of a record in pKey[], parse the
+** record into a UnpackedRecord structure.  Return a pointer to
+** that structure.
 **
-** P2 is the number of columns in the virtual table.
-** The cursor points to a BTree table if P4==0 and to a BTree index
-** if P4 is not 0.  If P4 is not NULL, it points to a KeyInfo structure
-** that defines the format of keys in the index.
+** The calling function might provide szSpace bytes of memory
+** space at pSpace.  This space can be used to hold the returned
+** VDbeParsedRecord structure if it is large enough.  If it is
+** not big enough, space is obtained from sqlite3_malloc().
 **
-** This opcode was once called OpenTemp.  But that created
-** confusion because the term "temp table", might refer either
-** to a TEMP table at the SQL level, or to a table opened by
-** this opcode.  Then this opcode was call OpenVirtual.  But
-** that created confusion with the whole virtual-table idea.
-*/
-case OP_OpenEphemeral: {
-  int i = pOp->p1;
-  Cursor *pCx;
-  static const int openFlags = 
-      SQLITE_OPEN_READWRITE |
-      SQLITE_OPEN_CREATE |
-      SQLITE_OPEN_EXCLUSIVE |
-      SQLITE_OPEN_DELETEONCLOSE |
-      SQLITE_OPEN_TRANSIENT_DB;
-
-  assert( i>=0 );
-  pCx = allocateCursor(p, i, pOp, -1, 1);
-  if( pCx==0 ) goto no_mem;
-  pCx->nullRow = 1;
-  rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
-                           &pCx->pBt);
-  if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);
+** The returned structure should be closed by a call to
+** sqlite3VdbeDeleteUnpackedRecord().
+*/ 
+SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(
+  KeyInfo *pKeyInfo,     /* Information about the record format */
+  int nKey,              /* Size of the binary record */
+  const void *pKey,      /* The binary record */
+  char *pSpace,          /* Unaligned space available to hold the object */
+  int szSpace            /* Size of pSpace[] in bytes */
+){
+  const unsigned char *aKey = (const unsigned char *)pKey;
+  UnpackedRecord *p;  /* The unpacked record that we will return */
+  int nByte;          /* Memory space needed to hold p, in bytes */
+  int d;
+  u32 idx;
+  u16 u;              /* Unsigned loop counter */
+  u32 szHdr;
+  Mem *pMem;
+  int nOff;           /* Increase pSpace by this much to 8-byte align it */
+  
+  /*
+  ** We want to shift the pointer pSpace up such that it is 8-byte aligned.
+  ** Thus, we need to calculate a value, nOff, between 0 and 7, to shift 
+  ** it by.  If pSpace is already 8-byte aligned, nOff should be zero.
+  */
+  nOff = (8 - (SQLITE_PTR_TO_INT(pSpace) & 7)) & 7;
+  pSpace += nOff;
+  szSpace -= nOff;
+  nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1);
+  if( nByte>szSpace ){
+    p = sqlite3DbMallocRaw(pKeyInfo->db, nByte);
+    if( p==0 ) return 0;
+    p->flags = UNPACKED_NEED_FREE | UNPACKED_NEED_DESTROY;
+  }else{
+    p = (UnpackedRecord*)pSpace;
+    p->flags = UNPACKED_NEED_DESTROY;
   }
-  if( rc==SQLITE_OK ){
-    /* If a transient index is required, create it by calling
-    ** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
-    ** opening it. If a transient table is required, just use the
-    ** automatically created table with root-page 1 (an INTKEY table).
-    */
-    if( pOp->p4.pKeyInfo ){
-      int pgno;
-      assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_ZERODATA); 
-      if( rc==SQLITE_OK ){
-        assert( pgno==MASTER_ROOT+1 );
-        rc = sqlite3BtreeCursor(pCx->pBt, pgno, 1, 
-                                (KeyInfo*)pOp->p4.z, pCx->pCursor);
-        pCx->pKeyInfo = pOp->p4.pKeyInfo;
-        pCx->pKeyInfo->enc = ENC(p->db);
-        pCx->pIncrKey = &pCx->pKeyInfo->incrKey;
-      }
-      pCx->isTable = 0;
-    }else{
-      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, pCx->pCursor);
-      pCx->isTable = 1;
-      pCx->pIncrKey = &pCx->bogusIncrKey;
-    }
+  p->pKeyInfo = pKeyInfo;
+  p->nField = pKeyInfo->nField + 1;
+  p->aMem = pMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
+  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
+  idx = getVarint32(aKey, szHdr);
+  d = szHdr;
+  u = 0;
+  while( idx<szHdr && u<p->nField && d<=nKey ){
+    u32 serial_type;
+
+    idx += getVarint32(&aKey[idx], serial_type);
+    pMem->enc = pKeyInfo->enc;
+    pMem->db = pKeyInfo->db;
+    pMem->flags = 0;
+    pMem->zMalloc = 0;
+    d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
+    pMem++;
+    u++;
   }
-  pCx->isIndex = !pCx->isTable;
-  break;
+  assert( u<=pKeyInfo->nField + 1 );
+  p->nField = u;
+  return (void*)p;
 }
 
-/* Opcode: OpenPseudo P1 P2 * * *
-**
-** Open a new cursor that points to a fake table that contains a single
-** row of data.  Any attempt to write a second row of data causes the
-** first row to be deleted.  All data is deleted when the cursor is
-** closed.
-**
-** A pseudo-table created by this opcode is useful for holding the
-** NEW or OLD tables in a trigger.  Also used to hold the a single
-** row output from the sorter so that the row can be decomposed into
-** individual columns using the OP_Column opcode.
-**
-** When OP_Insert is executed to insert a row in to the pseudo table,
-** the pseudo-table cursor may or may not make it's own copy of the
-** original row data. If P2 is 0, then the pseudo-table will copy the
-** original row data. Otherwise, a pointer to the original memory cell
-** is stored. In this case, the vdbe program must ensure that the 
-** memory cell containing the row data is not overwritten until the
-** pseudo table is closed (or a new row is inserted into it).
+/*
+** This routine destroys a UnpackedRecord object.
 */
-case OP_OpenPseudo: {
-  int i = pOp->p1;
-  Cursor *pCx;
-  assert( i>=0 );
-  pCx = allocateCursor(p, i, &pOp[-1], -1, 0);
-  if( pCx==0 ) goto no_mem;
-  pCx->nullRow = 1;
-  pCx->pseudoTable = 1;
-  pCx->ephemPseudoTable = pOp->p2;
-  pCx->pIncrKey = &pCx->bogusIncrKey;
-  pCx->isTable = 1;
-  pCx->isIndex = 0;
-  break;
-}
+SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord *p){
+  int i;
+  Mem *pMem;
 
-/* Opcode: Close P1 * * * *
-**
-** Close a cursor previously opened as P1.  If P1 is not
-** currently open, this instruction is a no-op.
-*/
-case OP_Close: {
-  int i = pOp->p1;
-  assert( i>=0 && i<p->nCursor );
-  sqlite3VdbeFreeCursor(p, p->apCsr[i]);
-  p->apCsr[i] = 0;
-  break;
+  assert( p!=0 );
+  assert( p->flags & UNPACKED_NEED_DESTROY );
+  for(i=0, pMem=p->aMem; i<p->nField; i++, pMem++){
+    /* The unpacked record is always constructed by the
+    ** sqlite3VdbeUnpackRecord() function above, which makes all
+    ** strings and blobs static.  And none of the elements are
+    ** ever transformed, so there is never anything to delete.
+    */
+    if( NEVER(pMem->zMalloc) ) sqlite3VdbeMemRelease(pMem);
+  }
+  if( p->flags & UNPACKED_NEED_FREE ){
+    sqlite3DbFree(p->pKeyInfo->db, p);
+  }
 }
 
-/* Opcode: MoveGe P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the integer value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the smallest entry that 
-** is greater than or equal to the key value. If there are no records 
-** greater than or equal to the key and P2 is not zero, then jump to P2.
-**
-** A special feature of this opcode (and different from the
-** related OP_MoveGt, OP_MoveLt, and OP_MoveLe) is that if P2 is
-** zero and P1 is an SQL table (a b-tree with integer keys) then
-** the seek is deferred until it is actually needed.  It might be
-** the case that the cursor is never accessed.  By deferring the
-** seek, we avoid unnecessary seeks.
-**
-** See also: Found, NotFound, Distinct, MoveLt, MoveGt, MoveLe
-*/
-/* Opcode: MoveGt P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the integer value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the smallest entry that 
-** is greater than the key value. If there are no records greater than 
-** the key and P2 is not zero, then jump to P2.
+/*
+** This function compares the two table rows or index records
+** specified by {nKey1, pKey1} and pPKey2.  It returns a negative, zero
+** or positive integer if key1 is less than, equal to or 
+** greater than key2.  The {nKey1, pKey1} key must be a blob
+** created by th OP_MakeRecord opcode of the VDBE.  The pPKey2
+** key must be a parsed key such as obtained from
+** sqlite3VdbeParseRecord.
 **
-** See also: Found, NotFound, Distinct, MoveLt, MoveGe, MoveLe
+** Key1 and Key2 do not have to contain the same number of fields.
+** The key with fewer fields is usually compares less than the 
+** longer key.  However if the UNPACKED_INCRKEY flags in pPKey2 is set
+** and the common prefixes are equal, then key1 is less than key2.
+** Or if the UNPACKED_MATCH_PREFIX flag is set and the prefixes are
+** equal, then the keys are considered to be equal and
+** the parts beyond the common prefix are ignored.
+**
+** If the UNPACKED_IGNORE_ROWID flag is set, then the last byte of
+** the header of pKey1 is ignored.  It is assumed that pKey1 is
+** an index key, and thus ends with a rowid value.  The last byte
+** of the header will therefore be the serial type of the rowid:
+** one of 1, 2, 3, 4, 5, 6, 8, or 9 - the integer serial types.
+** The serial type of the final rowid will always be a single byte.
+** By ignoring this last byte of the header, we force the comparison
+** to ignore the rowid at the end of key1.
 */
-/* Opcode: MoveLt P1 P2 P3 P4 * 
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the integer value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the largest entry that 
-** is less than the key value. If there are no records less than 
-** the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLe
-*/
-/* Opcode: MoveLe P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the integer value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that it points to the largest entry that 
-** is less than or equal to the key value. If there are no records 
-** less than or equal to the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLt
-*/
-case OP_MoveLt:         /* jump, in3 */
-case OP_MoveLe:         /* jump, in3 */
-case OP_MoveGe:         /* jump, in3 */
-case OP_MoveGt: {       /* jump, in3 */
-  int i = pOp->p1;
-  Cursor *pC;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  if( pC->pCursor!=0 ){
-    int res, oc;
-    oc = pOp->opcode;
-    pC->nullRow = 0;
-    *pC->pIncrKey = oc==OP_MoveGt || oc==OP_MoveLe;
-    if( pC->isTable ){
-      i64 iKey = sqlite3VdbeIntValue(pIn3);
-      if( pOp->p2==0 ){
-        assert( pOp->opcode==OP_MoveGe );
-        pC->movetoTarget = iKey;
-        pC->rowidIsValid = 0;
-        pC->deferredMoveto = 1;
-        break;
-      }
-      rc = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)iKey, 0, &res);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      pC->lastRowid = iKey;
-      pC->rowidIsValid = res==0;
-    }else{
-      UnpackedRecord r;
-      int nField = pOp->p4.i;
-      assert( pOp->p4type==P4_INT32 );
-      assert( nField>0 );
-      r.pKeyInfo = pC->pKeyInfo;
-      r.nField = nField;
-      r.needFree = 0;
-      r.needDestroy = 0;
-      r.aMem = &p->aMem[pOp->p3];
-      rc = sqlite3BtreeMoveto(pC->pCursor, 0, &r, 0, 0, &res);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      pC->rowidIsValid = 0;
-    }
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-    *pC->pIncrKey = 0;
-#ifdef SQLITE_TEST
-    sqlite3_search_count++;
-#endif
-    if( oc==OP_MoveGe || oc==OP_MoveGt ){
-      if( res<0 ){
-        rc = sqlite3BtreeNext(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        pC->rowidIsValid = 0;
-      }else{
-        res = 0;
-      }
-    }else{
-      assert( oc==OP_MoveLt || oc==OP_MoveLe );
-      if( res>=0 ){
-        rc = sqlite3BtreePrevious(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        pC->rowidIsValid = 0;
-      }else{
-        /* res might be negative because the table is empty.  Check to
-        ** see if this is the case.
-        */
-        res = sqlite3BtreeEof(pC->pCursor);
-      }
-    }
-    assert( pOp->p2>0 );
-    if( res ){
-      pc = pOp->p2 - 1;
-    }
-  }
-  break;
-}
+SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
+  int nKey1, const void *pKey1, /* Left key */
+  UnpackedRecord *pPKey2        /* Right key */
+){
+  int d1;            /* Offset into aKey[] of next data element */
+  u32 idx1;          /* Offset into aKey[] of next header element */
+  u32 szHdr1;        /* Number of bytes in header */
+  int i = 0;
+  int nField;
+  int rc = 0;
+  const unsigned char *aKey1 = (const unsigned char *)pKey1;
+  KeyInfo *pKeyInfo;
+  Mem mem1;
 
-/* Opcode: Found P1 P2 P3 * *
-**
-** Register P3 holds a blob constructed by MakeRecord.  P1 is an index.
-** If an entry that matches the value in register p3 exists in P1 then
-** jump to P2.  If the P3 value does not match any entry in P1
-** then fall thru.  The P1 cursor is left pointing at the matching entry
-** if it exists.
-**
-** This instruction is used to implement the IN operator where the
-** left-hand side is a SELECT statement.  P1 may be a true index, or it
-** may be a temporary index that holds the results of the SELECT
-** statement.   This instruction is also used to implement the
-** DISTINCT keyword in SELECT statements.
-**
-** This instruction checks if index P1 contains a record for which 
-** the first N serialised values exactly match the N serialised values
-** in the record in register P3, where N is the total number of values in
-** the P3 record (the P3 record is a prefix of the P1 record). 
-**
-** See also: NotFound, MoveTo, IsUnique, NotExists
-*/
-/* Opcode: NotFound P1 P2 P3 * *
-**
-** Register P3 holds a blob constructed by MakeRecord.  P1 is
-** an index.  If no entry exists in P1 that matches the blob then jump
-** to P2.  If an entry does existing, fall through.  The cursor is left
-** pointing to the entry that matches.
-**
-** See also: Found, MoveTo, NotExists, IsUnique
-*/
-case OP_NotFound:       /* jump, in3 */
-case OP_Found: {        /* jump, in3 */
-  int i = pOp->p1;
-  int alreadyExists = 0;
-  Cursor *pC;
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pC = p->apCsr[i])->pCursor!=0 ){
-    int res;
-    assert( pC->isTable==0 );
-    assert( pIn3->flags & MEM_Blob );
-    if( pOp->opcode==OP_Found ){
-      pC->pKeyInfo->prefixIsEqual = 1;
-    }
-    rc = sqlite3BtreeMoveto(pC->pCursor, pIn3->z, 0, pIn3->n, 0, &res);
-    pC->pKeyInfo->prefixIsEqual = 0;
-    if( rc!=SQLITE_OK ){
-      break;
-    }
-    alreadyExists = (res==0);
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-  }
-  if( pOp->opcode==OP_Found ){
-    if( alreadyExists ) pc = pOp->p2 - 1;
-  }else{
-    if( !alreadyExists ) pc = pOp->p2 - 1;
+  pKeyInfo = pPKey2->pKeyInfo;
+  mem1.enc = pKeyInfo->enc;
+  mem1.db = pKeyInfo->db;
+  mem1.flags = 0;
+  mem1.u.i = 0;  /* not needed, here to silence compiler warning */
+  mem1.zMalloc = 0;
+  
+  idx1 = getVarint32(aKey1, szHdr1);
+  d1 = szHdr1;
+  if( pPKey2->flags & UNPACKED_IGNORE_ROWID ){
+    szHdr1--;
   }
-  break;
-}
-
-/* Opcode: IsUnique P1 P2 P3 P4 *
-**
-** The P3 register contains an integer record number.  Call this
-** record number R.  The P4 register contains an index key created
-** using MakeIdxRec.  Call it K.
-**
-** P1 is an index.  So it has no data and its key consists of a
-** record generated by OP_MakeRecord where the last field is the 
-** rowid of the entry that the index refers to.
-** 
-** This instruction asks if there is an entry in P1 where the
-** fields matches K but the rowid is different from R.
-** If there is no such entry, then there is an immediate
-** jump to P2.  If any entry does exist where the index string
-** matches K but the record number is not R, then the record
-** number for that entry is written into P3 and control
-** falls through to the next instruction.
-**
-** See also: NotFound, NotExists, Found
-*/
-case OP_IsUnique: {        /* jump, in3 */
-  int i = pOp->p1;
-  Cursor *pCx;
-  BtCursor *pCrsr;
-  Mem *pK;
-  i64 R;
+  nField = pKeyInfo->nField;
+  while( idx1<szHdr1 && i<pPKey2->nField ){
+    u32 serial_type1;
 
-  /* Pop the value R off the top of the stack
-  */
-  assert( pOp->p4type==P4_INT32 );
-  assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
-  pK = &p->aMem[pOp->p4.i];
-  sqlite3VdbeMemIntegerify(pIn3);
-  R = pIn3->u.i;
-  assert( i>=0 && i<p->nCursor );
-  pCx = p->apCsr[i];
-  assert( pCx!=0 );
-  pCrsr = pCx->pCursor;
-  if( pCrsr!=0 ){
-    int res;
-    i64 v;         /* The record number on the P1 entry that matches K */
-    char *zKey;    /* The value of K */
-    int nKey;      /* Number of bytes in K */
-    int len;       /* Number of bytes in K without the rowid at the end */
-    int szRowid;   /* Size of the rowid column at the end of zKey */
+    /* Read the serial types for the next element in each key. */
+    idx1 += getVarint32( aKey1+idx1, serial_type1 );
+    if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
 
-    /* Make sure K is a string and make zKey point to K
+    /* Extract the values to be compared.
     */
-    assert( pK->flags & MEM_Blob );
-    zKey = pK->z;
-    nKey = pK->n;
-
-    szRowid = sqlite3VdbeIdxRowidLen((u8*)zKey);
-    len = nKey-szRowid;
+    d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
 
-    /* Search for an entry in P1 where all but the last four bytes match K.
-    ** If there is no such entry, jump immediately to P2.
+    /* Do the comparison
     */
-    assert( pCx->deferredMoveto==0 );
-    pCx->cacheStatus = CACHE_STALE;
-    rc = sqlite3BtreeMoveto(pCrsr, zKey, 0, len, 0, &res);
-    if( rc!=SQLITE_OK ){
-      goto abort_due_to_error;
-    }
-    if( res<0 ){
-      rc = sqlite3BtreeNext(pCrsr, &res);
-      if( res ){
-        pc = pOp->p2 - 1;
-        break;
-      }
-    }
-    rc = sqlite3VdbeIdxKeyCompare(pCx, 0, len, (u8*)zKey, &res); 
-    if( rc!=SQLITE_OK ) goto abort_due_to_error;
-    if( res>0 ){
-      pc = pOp->p2 - 1;
+    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
+                           i<nField ? pKeyInfo->aColl[i] : 0);
+    if( rc!=0 ){
       break;
     }
+    i++;
+  }
 
-    /* At this point, pCrsr is pointing to an entry in P1 where all but
-    ** the final entry (the rowid) matches K.  Check to see if the
-    ** final rowid column is different from R.  If it equals R then jump
-    ** immediately to P2.
-    */
-    rc = sqlite3VdbeIdxRowid(pCrsr, &v);
-    if( rc!=SQLITE_OK ){
-      goto abort_due_to_error;
-    }
-    if( v==R ){
-      pc = pOp->p2 - 1;
-      break;
-    }
+  /* No memory allocation is ever used on mem1. */
+  if( NEVER(mem1.zMalloc) ) sqlite3VdbeMemRelease(&mem1);
 
-    /* The final varint of the key is different from R.  Store it back
-    ** into register R3.  (The record number of an entry that violates
-    ** a UNIQUE constraint.)
-    */
-    pIn3->u.i = v;
-    assert( pIn3->flags&MEM_Int );
+  /* If the PREFIX_SEARCH flag is set and all fields except the final
+  ** rowid field were equal, then clear the PREFIX_SEARCH flag and set 
+  ** pPKey2->rowid to the value of the rowid field in (pKey1, nKey1).
+  ** This is used by the OP_IsUnique opcode.
+  */
+  if( (pPKey2->flags & UNPACKED_PREFIX_SEARCH) && i==(pPKey2->nField-1) ){
+    assert( idx1==szHdr1 && rc );
+    assert( mem1.flags & MEM_Int );
+    pPKey2->flags &= ~UNPACKED_PREFIX_SEARCH;
+    pPKey2->rowid = mem1.u.i;
   }
-  break;
-}
 
-/* Opcode: NotExists P1 P2 P3 * *
-**
-** Use the content of register P3 as a integer key.  If a record 
-** with that key does not exist in table of P1, then jump to P2. 
-** If the record does exist, then fall thru.  The cursor is left 
-** pointing to the record if it exists.
-**
-** The difference between this operation and NotFound is that this
-** operation assumes the key is an integer and that P1 is a table whereas
-** NotFound assumes key is a blob constructed from MakeRecord and
-** P1 is an index.
-**
-** See also: Found, MoveTo, NotFound, IsUnique
-*/
-case OP_NotExists: {        /* jump, in3 */
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
-    int res;
-    u64 iKey;
-    assert( pIn3->flags & MEM_Int );
-    assert( p->apCsr[i]->isTable );
-    iKey = intToKey(pIn3->u.i);
-    rc = sqlite3BtreeMoveto(pCrsr, 0, 0, iKey, 0,&res);
-    pC->lastRowid = pIn3->u.i;
-    pC->rowidIsValid = res==0;
-    pC->nullRow = 0;
-    pC->cacheStatus = CACHE_STALE;
-    /* res might be uninitialized if rc!=SQLITE_OK.  But if rc!=SQLITE_OK
-    ** processing is about to abort so we really do not care whether or not
-    ** the following jump is taken.  (In other words, do not stress over
-    ** the error that valgrind sometimes shows on the next statement when
-    ** running ioerr.test and similar failure-recovery test scripts.) */
-    if( res!=0 ){
-      pc = pOp->p2 - 1;
-      assert( pC->rowidIsValid==0 );
+  if( rc==0 ){
+    /* rc==0 here means that one of the keys ran out of fields and
+    ** all the fields up to that point were equal. If the UNPACKED_INCRKEY
+    ** flag is set, then break the tie by treating key2 as larger.
+    ** If the UPACKED_PREFIX_MATCH flag is set, then keys with common prefixes
+    ** are considered to be equal.  Otherwise, the longer key is the 
+    ** larger.  As it happens, the pPKey2 will always be the longer
+    ** if there is a difference.
+    */
+    if( pPKey2->flags & UNPACKED_INCRKEY ){
+      rc = -1;
+    }else if( pPKey2->flags & UNPACKED_PREFIX_MATCH ){
+      /* Leave rc==0 */
+    }else if( idx1<szHdr1 ){
+      rc = 1;
     }
+  }else if( pKeyInfo->aSortOrder && i<pKeyInfo->nField
+               && pKeyInfo->aSortOrder[i] ){
+    rc = -rc;
   }
-  break;
-}
 
-/* Opcode: Sequence P1 P2 * * *
-**
-** Find the next available sequence number for cursor P1.
-** Write the sequence number into register P2.
-** The sequence number on the cursor is incremented after this
-** instruction.  
-*/
-case OP_Sequence: {           /* out2-prerelease */
-  int i = pOp->p1;
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  pOut->u.i = p->apCsr[i]->seqCount++;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
+  return rc;
 }
+ 
 
-
-/* Opcode: NewRowid P1 P2 P3 * *
-**
-** Get a new integer record number (a.k.a "rowid") used as the key to a table.
-** The record number is not previously used as a key in the database
-** table that cursor P1 points to.  The new record number is written
-** written to register P2.
+/*
+** pCur points at an index entry created using the OP_MakeRecord opcode.
+** Read the rowid (the last field in the record) and store it in *rowid.
+** Return SQLITE_OK if everything works, or an error code otherwise.
 **
-** If P3>0 then P3 is a register that holds the largest previously
-** generated record number.  No new record numbers are allowed to be less
-** than this value.  When this value reaches its maximum, a SQLITE_FULL
-** error is generated.  The P3 register is updated with the generated
-** record number.  This P3 mechanism is used to help implement the
-** AUTOINCREMENT feature.
+** pCur might be pointing to text obtained from a corrupt database file.
+** So the content cannot be trusted.  Do appropriate checks on the content.
 */
-case OP_NewRowid: {           /* out2-prerelease */
-  int i = pOp->p1;
-  i64 v = 0;
-  Cursor *pC;
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pC = p->apCsr[i])->pCursor==0 ){
-    /* The zero initialization above is all that is needed */
-  }else{
-    /* The next rowid or record number (different terms for the same
-    ** thing) is obtained in a two-step algorithm.
-    **
-    ** First we attempt to find the largest existing rowid and add one
-    ** to that.  But if the largest existing rowid is already the maximum
-    ** positive integer, we have to fall through to the second
-    ** probabilistic algorithm
-    **
-    ** The second algorithm is to select a rowid at random and see if
-    ** it already exists in the table.  If it does not exist, we have
-    ** succeeded.  If the random rowid does exist, we select a new one
-    ** and try again, up to 1000 times.
-    **
-    ** For a table with less than 2 billion entries, the probability
-    ** of not finding a unused rowid is about 1.0e-300.  This is a 
-    ** non-zero probability, but it is still vanishingly small and should
-    ** never cause a problem.  You are much, much more likely to have a
-    ** hardware failure than for this algorithm to fail.
-    **
-    ** The analysis in the previous paragraph assumes that you have a good
-    ** source of random numbers.  Is a library function like lrand48()
-    ** good enough?  Maybe. Maybe not. It's hard to know whether there
-    ** might be subtle bugs is some implementations of lrand48() that
-    ** could cause problems. To avoid uncertainty, SQLite uses its own 
-    ** random number generator based on the RC4 algorithm.
-    **
-    ** To promote locality of reference for repetitive inserts, the
-    ** first few attempts at chosing a random rowid pick values just a little
-    ** larger than the previous rowid.  This has been shown experimentally
-    ** to double the speed of the COPY operation.
-    */
-    int res, rx=SQLITE_OK, cnt;
-    i64 x;
-    cnt = 0;
-    if( (sqlite3BtreeFlags(pC->pCursor)&(BTREE_INTKEY|BTREE_ZERODATA)) !=
-          BTREE_INTKEY ){
-      rc = SQLITE_CORRUPT_BKPT;
-      goto abort_due_to_error;
-    }
-    assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_INTKEY)!=0 );
-    assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_ZERODATA)==0 );
-
-#ifdef SQLITE_32BIT_ROWID
-#   define MAX_ROWID 0x7fffffff
-#else
-    /* Some compilers complain about constants of the form 0x7fffffffffffffff.
-    ** Others complain about 0x7ffffffffffffffffLL.  The following macro seems
-    ** to provide the constant while making all compilers happy.
-    */
-#   define MAX_ROWID  ( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
-#endif
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3 *db, BtCursor *pCur, i64 *rowid){
+  i64 nCellKey = 0;
+  int rc;
+  u32 szHdr;        /* Size of the header */
+  u32 typeRowid;    /* Serial type of the rowid */
+  u32 lenRowid;     /* Size of the rowid */
+  Mem m, v;
 
-    if( !pC->useRandomRowid ){
-      if( pC->nextRowidValid ){
-        v = pC->nextRowid;
-      }else{
-        rc = sqlite3BtreeLast(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ){
-          goto abort_due_to_error;
-        }
-        if( res ){
-          v = 1;
-        }else{
-          sqlite3BtreeKeySize(pC->pCursor, &v);
-          v = keyToInt(v);
-          if( v==MAX_ROWID ){
-            pC->useRandomRowid = 1;
-          }else{
-            v++;
-          }
-        }
-      }
+  UNUSED_PARAMETER(db);
 
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-      if( pOp->p3 ){
-        Mem *pMem;
-        assert( pOp->p3>0 && pOp->p3<=p->nMem ); /* P3 is a valid memory cell */
-        pMem = &p->aMem[pOp->p3];
-	REGISTER_TRACE(pOp->p3, pMem);
-        sqlite3VdbeMemIntegerify(pMem);
-        assert( (pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
-        if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
-          rc = SQLITE_FULL;
-          goto abort_due_to_error;
-        }
-        if( v<pMem->u.i+1 ){
-          v = pMem->u.i + 1;
-        }
-        pMem->u.i = v;
-      }
-#endif
+  /* Get the size of the index entry.  Only indices entries of less
+  ** than 2GiB are support - anything large must be database corruption.
+  ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
+  ** this code can safely assume that nCellKey is 32-bits  
+  */
+  assert( sqlite3BtreeCursorIsValid(pCur) );
+  rc = sqlite3BtreeKeySize(pCur, &nCellKey);
+  assert( rc==SQLITE_OK );     /* pCur is always valid so KeySize cannot fail */
+  assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );
 
-      if( v<MAX_ROWID ){
-        pC->nextRowidValid = 1;
-        pC->nextRowid = v+1;
-      }else{
-        pC->nextRowidValid = 0;
-      }
-    }
-    if( pC->useRandomRowid ){
-      assert( pOp->p3==0 );  /* SQLITE_FULL must have occurred prior to this */
-      v = db->priorNewRowid;
-      cnt = 0;
-      do{
-        if( cnt==0 && (v&0xffffff)==v ){
-          v++;
-        }else{
-          sqlite3_randomness(sizeof(v), &v);
-          if( cnt<5 ) v &= 0xffffff;
-        }
-        if( v==0 ) continue;
-        x = intToKey(v);
-        rx = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)x, 0, &res);
-        cnt++;
-      }while( cnt<100 && rx==SQLITE_OK && res==0 );
-      db->priorNewRowid = v;
-      if( rx==SQLITE_OK && res==0 ){
-        rc = SQLITE_FULL;
-        goto abort_due_to_error;
-      }
-    }
-    pC->rowidIsValid = 0;
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
+  /* Read in the complete content of the index entry */
+  memset(&m, 0, sizeof(m));
+  rc = sqlite3VdbeMemFromBtree(pCur, 0, (int)nCellKey, 1, &m);
+  if( rc ){
+    return rc;
   }
-  MemSetTypeFlag(pOut, MEM_Int);
-  pOut->u.i = v;
-  break;
-}
 
-/* Opcode: Insert P1 P2 P3 P4 P5
-**
-** Write an entry into the table of cursor P1.  A new entry is
-** created if it doesn't already exist or the data for an existing
-** entry is overwritten.  The data is the value stored register
-** number P2. The key is stored in register P3. The key must
-** be an integer.
-**
-** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
-** incremented (otherwise not).  If the OPFLAG_LASTROWID flag of P5 is set,
-** then rowid is stored for subsequent return by the
-** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
-**
-** Parameter P4 may point to a string containing the table-name, or
-** may be NULL. If it is not NULL, then the update-hook 
-** (sqlite3.xUpdateCallback) is invoked following a successful insert.
-**
-** (WARNING/TODO: If P1 is a pseudo-cursor and P2 is dynamically
-** allocated, then ownership of P2 is transferred to the pseudo-cursor
-** and register P2 becomes ephemeral.  If the cursor is changed, the
-** value of register P2 will then change.  Make sure this does not
-** cause any problems.)
-**
-** This instruction only works on tables.  The equivalent instruction
-** for indices is OP_IdxInsert.
-*/
-case OP_Insert: {
-  Mem *pData = &p->aMem[pOp->p2];
-  Mem *pKey = &p->aMem[pOp->p3];
-
-  i64 iKey;   /* The integer ROWID or key for the record to be inserted */
-  int i = pOp->p1;
-  Cursor *pC;
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  assert( pC->pCursor!=0 || pC->pseudoTable );
-  assert( pKey->flags & MEM_Int );
-  assert( pC->isTable );
-  REGISTER_TRACE(pOp->p2, pData);
-  REGISTER_TRACE(pOp->p3, pKey);
-
-  iKey = intToKey(pKey->u.i);
-  if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
-  if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = pKey->u.i;
-  if( pC->nextRowidValid && pKey->u.i>=pC->nextRowid ){
-    pC->nextRowidValid = 0;
+  /* The index entry must begin with a header size */
+  (void)getVarint32((u8*)m.z, szHdr);
+  testcase( szHdr==3 );
+  testcase( szHdr==m.n );
+  if( unlikely(szHdr<3 || (int)szHdr>m.n) ){
+    goto idx_rowid_corruption;
   }
-  if( pData->flags & MEM_Null ){
-    pData->z = 0;
-    pData->n = 0;
-  }else{
-    assert( pData->flags & (MEM_Blob|MEM_Str) );
+
+  /* The last field of the index should be an integer - the ROWID.
+  ** Verify that the last entry really is an integer. */
+  (void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
+  testcase( typeRowid==1 );
+  testcase( typeRowid==2 );
+  testcase( typeRowid==3 );
+  testcase( typeRowid==4 );
+  testcase( typeRowid==5 );
+  testcase( typeRowid==6 );
+  testcase( typeRowid==8 );
+  testcase( typeRowid==9 );
+  if( unlikely(typeRowid<1 || typeRowid>9 || typeRowid==7) ){
+    goto idx_rowid_corruption;
   }
-  if( pC->pseudoTable ){
-    if( !pC->ephemPseudoTable ){
-      sqlite3_free(pC->pData);
-    }
-    pC->iKey = iKey;
-    pC->nData = pData->n;
-    if( pData->z==pData->zMalloc || pC->ephemPseudoTable ){
-      pC->pData = pData->z;
-      if( !pC->ephemPseudoTable ){
-        pData->flags &= ~MEM_Dyn;
-        pData->flags |= MEM_Ephem;
-        pData->zMalloc = 0;
-      }
-    }else{
-      pC->pData = sqlite3_malloc( pC->nData+2 );
-      if( !pC->pData ) goto no_mem;
-      memcpy(pC->pData, pData->z, pC->nData);
-      pC->pData[pC->nData] = 0;
-      pC->pData[pC->nData+1] = 0;
-    }
-    pC->nullRow = 0;
-  }else{
-    int nZero;
-    if( pData->flags & MEM_Zero ){
-      nZero = pData->u.i;
-    }else{
-      nZero = 0;
-    }
-    rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
-                            pData->z, pData->n, nZero,
-                            pOp->p5 & OPFLAG_APPEND);
+  lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
+  testcase( (u32)m.n==szHdr+lenRowid );
+  if( unlikely((u32)m.n<szHdr+lenRowid) ){
+    goto idx_rowid_corruption;
   }
-  
-  pC->rowidIsValid = 0;
-  pC->deferredMoveto = 0;
-  pC->cacheStatus = CACHE_STALE;
 
-  /* Invoke the update-hook if required. */
-  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    const char *zDb = db->aDb[pC->iDb].zName;
-    const char *zTbl = pOp->p4.z;
-    int op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
-    assert( pC->isTable );
-    db->xUpdateCallback(db->pUpdateArg, op, zDb, zTbl, iKey);
-    assert( pC->iDb>=0 );
-  }
-  break;
+  /* Fetch the integer off the end of the index record */
+  sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
+  *rowid = v.u.i;
+  sqlite3VdbeMemRelease(&m);
+  return SQLITE_OK;
+
+  /* Jump here if database corruption is detected after m has been
+  ** allocated.  Free the m object and return SQLITE_CORRUPT. */
+idx_rowid_corruption:
+  testcase( m.zMalloc!=0 );
+  sqlite3VdbeMemRelease(&m);
+  return SQLITE_CORRUPT_BKPT;
 }
 
-/* Opcode: Delete P1 P2 * P4 *
-**
-** Delete the record at which the P1 cursor is currently pointing.
-**
-** The cursor will be left pointing at either the next or the previous
-** record in the table. If it is left pointing at the next record, then
-** the next Next instruction will be a no-op.  Hence it is OK to delete
-** a record from within an Next loop.
-**
-** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
-** incremented (otherwise not).
-**
-** P1 must not be pseudo-table.  It has to be a real table with
-** multiple rows.
+/*
+** Compare the key of the index entry that cursor pC is pointing to against
+** the key string in pUnpacked.  Write into *pRes a number
+** that is negative, zero, or positive if pC is less than, equal to,
+** or greater than pUnpacked.  Return SQLITE_OK on success.
 **
-** If P4 is not NULL, then it is the name of the table that P1 is
-** pointing to.  The update hook will be invoked, if it exists.
-** If P4 is not NULL then the P1 cursor must have been positioned
-** using OP_NotFound prior to invoking this opcode.
+** pUnpacked is either created without a rowid or is truncated so that it
+** omits the rowid at the end.  The rowid at the end of the index entry
+** is ignored as well.  Hence, this routine only compares the prefixes 
+** of the keys prior to the final rowid, not the entire key.
 */
-case OP_Delete: {
-  int i = pOp->p1;
-  i64 iKey;
-  Cursor *pC;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  assert( pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(
+  VdbeCursor *pC,             /* The cursor to compare against */
+  UnpackedRecord *pUnpacked,  /* Unpacked version of key to compare against */
+  int *res                    /* Write the comparison result here */
+){
+  i64 nCellKey = 0;
+  int rc;
+  BtCursor *pCur = pC->pCursor;
+  Mem m;
 
-  /* If the update-hook will be invoked, set iKey to the rowid of the
-  ** row being deleted.
-  */
-  if( db->xUpdateCallback && pOp->p4.z ){
-    assert( pC->isTable );
-    assert( pC->rowidIsValid );  /* lastRowid set by previous OP_NotFound */
-    iKey = pC->lastRowid;
+  assert( sqlite3BtreeCursorIsValid(pCur) );
+  rc = sqlite3BtreeKeySize(pCur, &nCellKey);
+  assert( rc==SQLITE_OK );    /* pCur is always valid so KeySize cannot fail */
+  /* nCellKey will always be between 0 and 0xffffffff because of the say
+  ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
+  if( nCellKey<=0 || nCellKey>0x7fffffff ){
+    *res = 0;
+    return SQLITE_CORRUPT;
+  }
+  memset(&m, 0, sizeof(m));
+  rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, (int)nCellKey, 1, &m);
+  if( rc ){
+    return rc;
   }
+  assert( pUnpacked->flags & UNPACKED_IGNORE_ROWID );
+  *res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
+  sqlite3VdbeMemRelease(&m);
+  return SQLITE_OK;
+}
 
-  rc = sqlite3VdbeCursorMoveto(pC);
-  if( rc ) goto abort_due_to_error;
-  rc = sqlite3BtreeDelete(pC->pCursor);
-  pC->nextRowidValid = 0;
-  pC->cacheStatus = CACHE_STALE;
+/*
+** This routine sets the value to be returned by subsequent calls to
+** sqlite3_changes() on the database handle 'db'. 
+*/
+SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
+  assert( sqlite3_mutex_held(db->mutex) );
+  db->nChange = nChange;
+  db->nTotalChange += nChange;
+}
 
-  /* Invoke the update-hook if required. */
-  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    const char *zDb = db->aDb[pC->iDb].zName;
-    const char *zTbl = pOp->p4.z;
-    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, iKey);
-    assert( pC->iDb>=0 );
-  }
-  if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
-  break;
+/*
+** Set a flag in the vdbe to update the change counter when it is finalised
+** or reset.
+*/
+SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe *v){
+  v->changeCntOn = 1;
 }
 
-/* Opcode: ResetCount P1 * *
+/*
+** Mark every prepared statement associated with a database connection
+** as expired.
 **
-** This opcode resets the VMs internal change counter to 0. If P1 is true,
-** then the value of the change counter is copied to the database handle
-** change counter (returned by subsequent calls to sqlite3_changes())
-** before it is reset. This is used by trigger programs.
+** An expired statement means that recompilation of the statement is
+** recommend.  Statements expire when things happen that make their
+** programs obsolete.  Removing user-defined functions or collating
+** sequences, or changing an authorization function are the types of
+** things that make prepared statements obsolete.
 */
-case OP_ResetCount: {
-  if( pOp->p1 ){
-    sqlite3VdbeSetChanges(db, p->nChange);
+SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3 *db){
+  Vdbe *p;
+  for(p = db->pVdbe; p; p=p->pNext){
+    p->expired = 1;
   }
-  p->nChange = 0;
-  break;
 }
 
-/* Opcode: RowData P1 P2 * * *
+/*
+** Return the database associated with the Vdbe.
+*/
+SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe *v){
+  return v->db;
+}
+
+/************** End of vdbeaux.c *********************************************/
+/************** Begin file vdbeapi.c *****************************************/
+/*
+** 2004 May 26
 **
-** Write into register P2 the complete row data for cursor P1.
-** There is no interpretation of the data.  
-** It is just copied onto the P2 register exactly as 
-** it is found in the database file.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** If the P1 cursor must be pointing to a valid row (not a NULL row)
-** of a real table, not a pseudo-table.
-*/
-/* Opcode: RowKey P1 P2 * * *
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** Write into register P2 the complete row key for cursor P1.
-** There is no interpretation of the data.  
-** The key is copied onto the P3 register exactly as 
-** it is found in the database file.
+*************************************************************************
 **
-** If the P1 cursor must be pointing to a valid row (not a NULL row)
-** of a real table, not a pseudo-table.
+** This file contains code use to implement APIs that are part of the
+** VDBE.
+**
+** $Id: vdbeapi.c,v 1.167 2009/06/25 01:47:12 drh Exp $
 */
-case OP_RowKey:
-case OP_RowData: {
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  u32 n;
-
-  pOut = &p->aMem[pOp->p2];
 
-  /* Note that RowKey and RowData are really exactly the same instruction */
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC->isTable || pOp->opcode==OP_RowKey );
-  assert( pC->isIndex || pOp->opcode==OP_RowData );
-  assert( pC!=0 );
-  assert( pC->nullRow==0 );
-  assert( pC->pseudoTable==0 );
-  assert( pC->pCursor!=0 );
-  pCrsr = pC->pCursor;
-  rc = sqlite3VdbeCursorMoveto(pC);
-  if( rc ) goto abort_due_to_error;
-  if( pC->isIndex ){
-    i64 n64;
-    assert( !pC->isTable );
-    sqlite3BtreeKeySize(pCrsr, &n64);
-    if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-      goto too_big;
-    }
-    n = n64;
-  }else{
-    sqlite3BtreeDataSize(pCrsr, &n);
-    if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-      goto too_big;
-    }
-  }
-  if( sqlite3VdbeMemGrow(pOut, n, 0) ){
-    goto no_mem;
-  }
-  pOut->n = n;
-  MemSetTypeFlag(pOut, MEM_Blob);
-  if( pC->isIndex ){
-    rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
-  }else{
-    rc = sqlite3BtreeData(pCrsr, 0, n, pOut->z);
-  }
-  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Return TRUE (non-zero) of the statement supplied as an argument needs
+** to be recompiled.  A statement needs to be recompiled whenever the
+** execution environment changes in a way that would alter the program
+** that sqlite3_prepare() generates.  For example, if new functions or
+** collating sequences are registered or if an authorizer function is
+** added or changed.
+*/
+SQLITE_API int sqlite3_expired(sqlite3_stmt *pStmt){
+  Vdbe *p = (Vdbe*)pStmt;
+  return p==0 || p->expired;
 }
+#endif
 
-/* Opcode: Rowid P1 P2 * * *
+/*
+** The following routine destroys a virtual machine that is created by
+** the sqlite3_compile() routine. The integer returned is an SQLITE_
+** success/failure code that describes the result of executing the virtual
+** machine.
 **
-** Store in register P2 an integer which is the key of the table entry that
-** P1 is currently point to.  If p2==0 then push the integer.
+** This routine sets the error code and string returned by
+** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
 */
-case OP_Rowid: {                 /* out2-prerelease */
-  int i = pOp->p1;
-  Cursor *pC;
-  i64 v;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  rc = sqlite3VdbeCursorMoveto(pC);
-  if( rc ) goto abort_due_to_error;
-  if( pC->rowidIsValid ){
-    v = pC->lastRowid;
-  }else if( pC->pseudoTable ){
-    v = keyToInt(pC->iKey);
-  }else if( pC->nullRow ){
-    /* Leave the rowid set to a NULL */
-    break;
+SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt){
+  int rc;
+  if( pStmt==0 ){
+    rc = SQLITE_OK;
   }else{
-    assert( pC->pCursor!=0 );
-    sqlite3BtreeKeySize(pC->pCursor, &v);
-    v = keyToInt(v);
+    Vdbe *v = (Vdbe*)pStmt;
+    sqlite3 *db = v->db;
+#if SQLITE_THREADSAFE
+    sqlite3_mutex *mutex = v->db->mutex;
+#endif
+    sqlite3_mutex_enter(mutex);
+    rc = sqlite3VdbeFinalize(v);
+    rc = sqlite3ApiExit(db, rc);
+    sqlite3_mutex_leave(mutex);
   }
-  pOut->u.i = v;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
+  return rc;
 }
 
-/* Opcode: NullRow P1 * * * *
+/*
+** Terminate the current execution of an SQL statement and reset it
+** back to its starting state so that it can be reused. A success code from
+** the prior execution is returned.
 **
-** Move the cursor P1 to a null row.  Any OP_Column operations
-** that occur while the cursor is on the null row will always
-** write a NULL.
+** This routine sets the error code and string returned by
+** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
 */
-case OP_NullRow: {
-  int i = pOp->p1;
-  Cursor *pC;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  pC->nullRow = 1;
-  pC->rowidIsValid = 0;
-  break;
+SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt){
+  int rc;
+  if( pStmt==0 ){
+    rc = SQLITE_OK;
+  }else{
+    Vdbe *v = (Vdbe*)pStmt;
+    sqlite3_mutex_enter(v->db->mutex);
+    rc = sqlite3VdbeReset(v);
+    sqlite3VdbeMakeReady(v, -1, 0, 0, 0, 0, 0);
+    assert( (rc & (v->db->errMask))==rc );
+    rc = sqlite3ApiExit(v->db, rc);
+    sqlite3_mutex_leave(v->db->mutex);
+  }
+  return rc;
 }
 
-/* Opcode: Last P1 P2 * * *
-**
-** The next use of the Rowid or Column or Next instruction for P1 
-** will refer to the last entry in the database table or index.
-** If the table or index is empty and P2>0, then jump immediately to P2.
-** If P2 is 0 or if the table or index is not empty, fall through
-** to the following instruction.
+/*
+** Set all the parameters in the compiled SQL statement to NULL.
 */
-case OP_Last: {        /* jump */
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  int res;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  pCrsr = pC->pCursor;
-  assert( pCrsr!=0 );
-  rc = sqlite3BtreeLast(pCrsr, &res);
-  pC->nullRow = res;
-  pC->deferredMoveto = 0;
-  pC->cacheStatus = CACHE_STALE;
-  if( res && pOp->p2>0 ){
-    pc = pOp->p2 - 1;
+SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt *pStmt){
+  int i;
+  int rc = SQLITE_OK;
+  Vdbe *p = (Vdbe*)pStmt;
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = ((Vdbe*)pStmt)->db->mutex;
+#endif
+  sqlite3_mutex_enter(mutex);
+  for(i=0; i<p->nVar; i++){
+    sqlite3VdbeMemRelease(&p->aVar[i]);
+    p->aVar[i].flags = MEM_Null;
   }
-  break;
+  sqlite3_mutex_leave(mutex);
+  return rc;
 }
 
 
-/* Opcode: Sort P1 P2 * * *
-**
-** This opcode does exactly the same thing as OP_Rewind except that
-** it increments an undocumented global variable used for testing.
-**
-** Sorting is accomplished by writing records into a sorting index,
-** then rewinding that index and playing it back from beginning to
-** end.  We use the OP_Sort opcode instead of OP_Rewind to do the
-** rewinding so that the global variable will be incremented and
-** regression tests can determine whether or not the optimizer is
-** correctly optimizing out sorts.
-*/
-case OP_Sort: {        /* jump */
-#ifdef SQLITE_TEST
-  sqlite3_sort_count++;
-  sqlite3_search_count--;
-#endif
-  /* Fall through into OP_Rewind */
-}
-/* Opcode: Rewind P1 P2 * * *
-**
-** The next use of the Rowid or Column or Next instruction for P1 
-** will refer to the first entry in the database table or index.
-** If the table or index is empty and P2>0, then jump immediately to P2.
-** If P2 is 0 or if the table or index is not empty, fall through
-** to the following instruction.
+/**************************** sqlite3_value_  *******************************
+** The following routines extract information from a Mem or sqlite3_value
+** structure.
 */
-case OP_Rewind: {        /* jump */
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  int res;
-
-  assert( i>=0 && i<p->nCursor );
-  pC = p->apCsr[i];
-  assert( pC!=0 );
-  if( (pCrsr = pC->pCursor)!=0 ){
-    rc = sqlite3BtreeFirst(pCrsr, &res);
-    pC->atFirst = res==0;
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
+SQLITE_API const void *sqlite3_value_blob(sqlite3_value *pVal){
+  Mem *p = (Mem*)pVal;
+  if( p->flags & (MEM_Blob|MEM_Str) ){
+    sqlite3VdbeMemExpandBlob(p);
+    p->flags &= ~MEM_Str;
+    p->flags |= MEM_Blob;
+    return p->z;
   }else{
-    res = 1;
-  }
-  pC->nullRow = res;
-  assert( pOp->p2>0 && pOp->p2<p->nOp );
-  if( res ){
-    pc = pOp->p2 - 1;
+    return sqlite3_value_text(pVal);
   }
-  break;
+}
+SQLITE_API int sqlite3_value_bytes(sqlite3_value *pVal){
+  return sqlite3ValueBytes(pVal, SQLITE_UTF8);
+}
+SQLITE_API int sqlite3_value_bytes16(sqlite3_value *pVal){
+  return sqlite3ValueBytes(pVal, SQLITE_UTF16NATIVE);
+}
+SQLITE_API double sqlite3_value_double(sqlite3_value *pVal){
+  return sqlite3VdbeRealValue((Mem*)pVal);
+}
+SQLITE_API int sqlite3_value_int(sqlite3_value *pVal){
+  return (int)sqlite3VdbeIntValue((Mem*)pVal);
+}
+SQLITE_API sqlite_int64 sqlite3_value_int64(sqlite3_value *pVal){
+  return sqlite3VdbeIntValue((Mem*)pVal);
+}
+SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value *pVal){
+  return (const unsigned char *)sqlite3ValueText(pVal, SQLITE_UTF8);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_value_text16(sqlite3_value* pVal){
+  return sqlite3ValueText(pVal, SQLITE_UTF16NATIVE);
+}
+SQLITE_API const void *sqlite3_value_text16be(sqlite3_value *pVal){
+  return sqlite3ValueText(pVal, SQLITE_UTF16BE);
+}
+SQLITE_API const void *sqlite3_value_text16le(sqlite3_value *pVal){
+  return sqlite3ValueText(pVal, SQLITE_UTF16LE);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+SQLITE_API int sqlite3_value_type(sqlite3_value* pVal){
+  return pVal->type;
 }
 
-/* Opcode: Next P1 P2 * * *
-**
-** Advance cursor P1 so that it points to the next key/data pair in its
-** table or index.  If there are no more key/value pairs then fall through
-** to the following instruction.  But if the cursor advance was successful,
-** jump immediately to P2.
-**
-** The P1 cursor must be for a real table, not a pseudo-table.
-**
-** See also: Prev
-*/
-/* Opcode: Prev P1 P2 * * *
-**
-** Back up cursor P1 so that it points to the previous key/data pair in its
-** table or index.  If there is no previous key/value pairs then fall through
-** to the following instruction.  But if the cursor backup was successful,
-** jump immediately to P2.
+/**************************** sqlite3_result_  *******************************
+** The following routines are used by user-defined functions to specify
+** the function result.
 **
-** The P1 cursor must be for a real table, not a pseudo-table.
+** The setStrOrError() funtion calls sqlite3VdbeMemSetStr() to store the
+** result as a string or blob but if the string or blob is too large, it
+** then sets the error code to SQLITE_TOOBIG
 */
-case OP_Prev:          /* jump */
-case OP_Next: {        /* jump */
-  Cursor *pC;
-  BtCursor *pCrsr;
-
-  CHECK_FOR_INTERRUPT;
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  if( pC==0 ){
-    break;  /* See ticket #2273 */
+static void setResultStrOrError(
+  sqlite3_context *pCtx,  /* Function context */
+  const char *z,          /* String pointer */
+  int n,                  /* Bytes in string, or negative */
+  u8 enc,                 /* Encoding of z.  0 for BLOBs */
+  void (*xDel)(void*)     /* Destructor function */
+){
+  if( sqlite3VdbeMemSetStr(&pCtx->s, z, n, enc, xDel)==SQLITE_TOOBIG ){
+    sqlite3_result_error_toobig(pCtx);
   }
-  pCrsr = pC->pCursor;
-  assert( pCrsr );
-  if( pC->nullRow==0 ){
-    int res = 1;
-    assert( pC->deferredMoveto==0 );
-    rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(pCrsr, &res) :
-                                sqlite3BtreePrevious(pCrsr, &res);
-    pC->nullRow = res;
-    pC->cacheStatus = CACHE_STALE;
-    if( res==0 ){
-      pc = pOp->p2 - 1;
-#ifdef SQLITE_TEST
-      sqlite3_search_count++;
+}
+SQLITE_API void sqlite3_result_blob(
+  sqlite3_context *pCtx, 
+  const void *z, 
+  int n, 
+  void (*xDel)(void *)
+){
+  assert( n>=0 );
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  setResultStrOrError(pCtx, z, n, 0, xDel);
+}
+SQLITE_API void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetDouble(&pCtx->s, rVal);
+}
+SQLITE_API void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  pCtx->isError = SQLITE_ERROR;
+  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, SQLITE_TRANSIENT);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API void sqlite3_result_error16(sqlite3_context *pCtx, const void *z, int n){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  pCtx->isError = SQLITE_ERROR;
+  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16NATIVE, SQLITE_TRANSIENT);
+}
 #endif
-    }
+SQLITE_API void sqlite3_result_int(sqlite3_context *pCtx, int iVal){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetInt64(&pCtx->s, (i64)iVal);
+}
+SQLITE_API void sqlite3_result_int64(sqlite3_context *pCtx, i64 iVal){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetInt64(&pCtx->s, iVal);
+}
+SQLITE_API void sqlite3_result_null(sqlite3_context *pCtx){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetNull(&pCtx->s);
+}
+SQLITE_API void sqlite3_result_text(
+  sqlite3_context *pCtx, 
+  const char *z, 
+  int n,
+  void (*xDel)(void *)
+){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  setResultStrOrError(pCtx, z, n, SQLITE_UTF8, xDel);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API void sqlite3_result_text16(
+  sqlite3_context *pCtx, 
+  const void *z, 
+  int n, 
+  void (*xDel)(void *)
+){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  setResultStrOrError(pCtx, z, n, SQLITE_UTF16NATIVE, xDel);
+}
+SQLITE_API void sqlite3_result_text16be(
+  sqlite3_context *pCtx, 
+  const void *z, 
+  int n, 
+  void (*xDel)(void *)
+){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  setResultStrOrError(pCtx, z, n, SQLITE_UTF16BE, xDel);
+}
+SQLITE_API void sqlite3_result_text16le(
+  sqlite3_context *pCtx, 
+  const void *z, 
+  int n, 
+  void (*xDel)(void *)
+){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  setResultStrOrError(pCtx, z, n, SQLITE_UTF16LE, xDel);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+SQLITE_API void sqlite3_result_value(sqlite3_context *pCtx, sqlite3_value *pValue){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemCopy(&pCtx->s, pValue);
+}
+SQLITE_API void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetZeroBlob(&pCtx->s, n);
+}
+SQLITE_API void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
+  pCtx->isError = errCode;
+  if( pCtx->s.flags & MEM_Null ){
+    sqlite3VdbeMemSetStr(&pCtx->s, sqlite3ErrStr(errCode), -1, 
+                         SQLITE_UTF8, SQLITE_STATIC);
   }
-  pC->rowidIsValid = 0;
-  break;
 }
 
-/* Opcode: IdxInsert P1 P2 P3 * *
-**
-** Register P2 holds a SQL index key made using the
-** MakeIdxRec instructions.  This opcode writes that key
-** into the index P1.  Data for the entry is nil.
-**
-** P3 is a flag that provides a hint to the b-tree layer that this
-** insert is likely to be an append.
-**
-** This instruction only works for indices.  The equivalent instruction
-** for tables is OP_Insert.
-*/
-case OP_IdxInsert: {        /* in2 */
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  assert( pIn2->flags & MEM_Blob );
-  if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
-    assert( pC->isTable==0 );
-    rc = ExpandBlob(pIn2);
-    if( rc==SQLITE_OK ){
-      int nKey = pIn2->n;
-      const char *zKey = pIn2->z;
-      rc = sqlite3BtreeInsert(pCrsr, zKey, nKey, "", 0, 0, pOp->p3);
-      assert( pC->deferredMoveto==0 );
-      pC->cacheStatus = CACHE_STALE;
-    }
-  }
-  break;
+/* Force an SQLITE_TOOBIG error. */
+SQLITE_API void sqlite3_result_error_toobig(sqlite3_context *pCtx){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  pCtx->isError = SQLITE_TOOBIG;
+  sqlite3VdbeMemSetStr(&pCtx->s, "string or blob too big", -1, 
+                       SQLITE_UTF8, SQLITE_STATIC);
 }
 
-/* Opcode: IdxDeleteM P1 P2 P3 * *
-**
-** The content of P3 registers starting at register P2 form
-** an unpacked index key. This opcode removes that entry from the 
-** index opened by cursor P1.
-*/
-case OP_IdxDelete: {
-  int i = pOp->p1;
-  Cursor *pC;
-  BtCursor *pCrsr;
-  assert( pOp->p3>0 );
-  assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem );
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
-    int res;
-    UnpackedRecord r;
-    r.pKeyInfo = pC->pKeyInfo;
-    r.nField = pOp->p3;
-    r.needFree = 0;
-    r.needDestroy = 0;
-    r.aMem = &p->aMem[pOp->p2];
-    rc = sqlite3BtreeMoveto(pCrsr, 0, &r, 0, 0, &res);
-    if( rc==SQLITE_OK && res==0 ){
-      rc = sqlite3BtreeDelete(pCrsr);
-    }
-    assert( pC->deferredMoveto==0 );
-    pC->cacheStatus = CACHE_STALE;
-  }
-  break;
+/* An SQLITE_NOMEM error. */
+SQLITE_API void sqlite3_result_error_nomem(sqlite3_context *pCtx){
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  sqlite3VdbeMemSetNull(&pCtx->s);
+  pCtx->isError = SQLITE_NOMEM;
+  pCtx->s.db->mallocFailed = 1;
 }
 
-/* Opcode: IdxRowid P1 P2 * * *
-**
-** Write into register P2 an integer which is the last entry in the record at
-** the end of the index key pointed to by cursor P1.  This integer should be
-** the rowid of the table entry to which this index entry points.
+/*
+** Execute the statement pStmt, either until a row of data is ready, the
+** statement is completely executed or an error occurs.
 **
-** See also: Rowid, MakeIdxRec.
+** This routine implements the bulk of the logic behind the sqlite_step()
+** API.  The only thing omitted is the automatic recompile if a 
+** schema change has occurred.  That detail is handled by the
+** outer sqlite3_step() wrapper procedure.
 */
-case OP_IdxRowid: {              /* out2-prerelease */
-  int i = pOp->p1;
-  BtCursor *pCrsr;
-  Cursor *pC;
+static int sqlite3Step(Vdbe *p){
+  sqlite3 *db;
+  int rc;
 
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
-    i64 rowid;
+  assert(p);
+  if( p->magic!=VDBE_MAGIC_RUN ){
+    return SQLITE_MISUSE;
+  }
 
-    assert( pC->deferredMoveto==0 );
-    assert( pC->isTable==0 );
-    if( !pC->nullRow ){
-      rc = sqlite3VdbeIdxRowid(pCrsr, &rowid);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      MemSetTypeFlag(pOut, MEM_Int);
-      pOut->u.i = rowid;
+  /* Assert that malloc() has not failed */
+  db = p->db;
+  if( db->mallocFailed ){
+    return SQLITE_NOMEM;
+  }
+
+  if( p->pc<=0 && p->expired ){
+    if( ALWAYS(p->rc==SQLITE_OK) ){
+      p->rc = SQLITE_SCHEMA;
     }
+    rc = SQLITE_ERROR;
+    goto end_of_step;
   }
-  break;
-}
+  if( sqlite3SafetyOn(db) ){
+    p->rc = SQLITE_MISUSE;
+    return SQLITE_MISUSE;
+  }
+  if( p->pc<0 ){
+    /* If there are no other statements currently running, then
+    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
+    ** from interrupting a statement that has not yet started.
+    */
+    if( db->activeVdbeCnt==0 ){
+      db->u1.isInterrupted = 0;
+    }
 
-/* Opcode: IdxGE P1 P2 P3 P4 P5
-**
-** The P4 register values beginning with P3 form an unpacked index 
-** key that omits the ROWID.  Compare this key value against the index 
-** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
-**
-** If the P1 index entry is greater than or equal to the key value
-** then jump to P2.  Otherwise fall through to the next instruction.
-**
-** If P5 is non-zero then the key value is increased by an epsilon 
-** prior to the comparison.  This make the opcode work like IdxGT except
-** that if the key from register P3 is a prefix of the key in the cursor,
-** the result is false whereas it would be true with IdxGT.
-*/
-/* Opcode: IdxLT P1 P2 P3 * P5
-**
-** The P4 register values beginning with P3 form an unpacked index 
-** key that omits the ROWID.  Compare this key value against the index 
-** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
-**
-** If the P1 index entry is less than the key value then jump to P2.
-** Otherwise fall through to the next instruction.
-**
-** If P5 is non-zero then the key value is increased by an epsilon prior 
-** to the comparison.  This makes the opcode work like IdxLE.
-*/
-case OP_IdxLT:          /* jump, in3 */
-case OP_IdxGE: {        /* jump, in3 */
-  int i= pOp->p1;
-  Cursor *pC;
+    assert( db->writeVdbeCnt>0 || db->autoCommit==0 || db->nDeferredCons==0 );
 
-  assert( i>=0 && i<p->nCursor );
-  assert( p->apCsr[i]!=0 );
-  if( (pC = p->apCsr[i])->pCursor!=0 ){
-    int res;
-    UnpackedRecord r;
-    assert( pC->deferredMoveto==0 );
-    assert( pOp->p5==0 || pOp->p5==1 );
-    assert( pOp->p4type==P4_INT32 );
-    r.pKeyInfo = pC->pKeyInfo;
-    r.nField = pOp->p4.i;
-    r.needFree = 0;
-    r.needDestroy = 0;
-    r.aMem = &p->aMem[pOp->p3];
-    *pC->pIncrKey = pOp->p5;
-    rc = sqlite3VdbeIdxKeyCompare(pC, &r, 0, 0, &res);
-    *pC->pIncrKey = 0;
-    if( pOp->opcode==OP_IdxLT ){
-      res = -res;
-    }else{
-      assert( pOp->opcode==OP_IdxGE );
-      res++;
-    }
-    if( res>0 ){
-      pc = pOp->p2 - 1 ;
+#ifndef SQLITE_OMIT_TRACE
+    if( db->xProfile && !db->init.busy ){
+      double rNow;
+      sqlite3OsCurrentTime(db->pVfs, &rNow);
+      p->startTime = (u64)((rNow - (int)rNow)*3600.0*24.0*1000000000.0);
     }
+#endif
+
+    db->activeVdbeCnt++;
+    if( p->readOnly==0 ) db->writeVdbeCnt++;
+    p->pc = 0;
   }
-  break;
+#ifndef SQLITE_OMIT_EXPLAIN
+  if( p->explain ){
+    rc = sqlite3VdbeList(p);
+  }else
+#endif /* SQLITE_OMIT_EXPLAIN */
+  {
+    rc = sqlite3VdbeExec(p);
+  }
+
+  if( sqlite3SafetyOff(db) ){
+    rc = SQLITE_MISUSE;
+  }
+
+#ifndef SQLITE_OMIT_TRACE
+  /* Invoke the profile callback if there is one
+  */
+  if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy && p->zSql ){
+    double rNow;
+    u64 elapseTime;
+
+    sqlite3OsCurrentTime(db->pVfs, &rNow);
+    elapseTime = (u64)((rNow - (int)rNow)*3600.0*24.0*1000000000.0);
+    elapseTime -= p->startTime;
+    db->xProfile(db->pProfileArg, p->zSql, elapseTime);
+  }
+#endif
+
+  db->errCode = rc;
+  if( SQLITE_NOMEM==sqlite3ApiExit(p->db, p->rc) ){
+    p->rc = SQLITE_NOMEM;
+  }
+end_of_step:
+  /* At this point local variable rc holds the value that should be 
+  ** returned if this statement was compiled using the legacy 
+  ** sqlite3_prepare() interface. According to the docs, this can only
+  ** be one of the values in the first assert() below. Variable p->rc 
+  ** contains the value that would be returned if sqlite3_finalize() 
+  ** were called on statement p.
+  */
+  assert( rc==SQLITE_ROW  || rc==SQLITE_DONE   || rc==SQLITE_ERROR 
+       || rc==SQLITE_BUSY || rc==SQLITE_MISUSE
+  );
+  assert( p->rc!=SQLITE_ROW && p->rc!=SQLITE_DONE );
+  if( p->isPrepareV2 && rc!=SQLITE_ROW && rc!=SQLITE_DONE ){
+    /* If this statement was prepared using sqlite3_prepare_v2(), and an
+    ** error has occured, then return the error code in p->rc to the
+    ** caller. Set the error code in the database handle to the same value.
+    */ 
+    rc = db->errCode = p->rc;
+  }
+  return (rc&db->errMask);
 }
 
-/* Opcode: Destroy P1 P2 P3 * *
-**
-** Delete an entire database table or index whose root page in the database
-** file is given by P1.
-**
-** The table being destroyed is in the main database file if P3==0.  If
-** P3==1 then the table to be clear is in the auxiliary database file
-** that is used to store tables create using CREATE TEMPORARY TABLE.
-**
-** If AUTOVACUUM is enabled then it is possible that another root page
-** might be moved into the newly deleted root page in order to keep all
-** root pages contiguous at the beginning of the database.  The former
-** value of the root page that moved - its value before the move occurred -
-** is stored in register P2.  If no page 
-** movement was required (because the table being dropped was already 
-** the last one in the database) then a zero is stored in register P2.
-** If AUTOVACUUM is disabled then a zero is stored in register P2.
-**
-** See also: Clear
+/*
+** This is the top-level implementation of sqlite3_step().  Call
+** sqlite3Step() to do most of the work.  If a schema error occurs,
+** call sqlite3Reprepare() and try again.
 */
-case OP_Destroy: {     /* out2-prerelease */
-  int iMoved;
-  int iCnt;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  Vdbe *pVdbe;
-  iCnt = 0;
-  for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
-    if( pVdbe->magic==VDBE_MAGIC_RUN && pVdbe->inVtabMethod<2 && pVdbe->pc>=0 ){
-      iCnt++;
+SQLITE_API int sqlite3_step(sqlite3_stmt *pStmt){
+  int rc = SQLITE_MISUSE;
+  if( pStmt ){
+    int cnt = 0;
+    Vdbe *v = (Vdbe*)pStmt;
+    sqlite3 *db = v->db;
+    sqlite3_mutex_enter(db->mutex);
+    while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
+           && cnt++ < 5
+           && (rc = sqlite3Reprepare(v))==SQLITE_OK ){
+      sqlite3_reset(pStmt);
+      v->expired = 0;
     }
-  }
-#else
-  iCnt = db->activeVdbeCnt;
-#endif
-  if( iCnt>1 ){
-    rc = SQLITE_LOCKED;
-    p->errorAction = OE_Abort;
-  }else{
-    int iDb = pOp->p3;
-    assert( iCnt==1 );
-    assert( (p->btreeMask & (1<<iDb))!=0 );
-    rc = sqlite3BtreeDropTable(db->aDb[iDb].pBt, pOp->p1, &iMoved);
-    MemSetTypeFlag(pOut, MEM_Int);
-    pOut->u.i = iMoved;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( rc==SQLITE_OK && iMoved!=0 ){
-      sqlite3RootPageMoved(&db->aDb[iDb], iMoved, pOp->p1);
+    if( rc==SQLITE_SCHEMA && ALWAYS(v->isPrepareV2) && ALWAYS(db->pErr) ){
+      /* This case occurs after failing to recompile an sql statement. 
+      ** The error message from the SQL compiler has already been loaded 
+      ** into the database handle. This block copies the error message 
+      ** from the database handle into the statement and sets the statement
+      ** program counter to 0 to ensure that when the statement is 
+      ** finalized or reset the parser error message is available via
+      ** sqlite3_errmsg() and sqlite3_errcode().
+      */
+      const char *zErr = (const char *)sqlite3_value_text(db->pErr); 
+      sqlite3DbFree(db, v->zErrMsg);
+      if( !db->mallocFailed ){
+        v->zErrMsg = sqlite3DbStrDup(db, zErr);
+      } else {
+        v->zErrMsg = 0;
+        v->rc = SQLITE_NOMEM;
+      }
     }
-#endif
+    rc = sqlite3ApiExit(db, rc);
+    sqlite3_mutex_leave(db->mutex);
   }
-  break;
+  return rc;
 }
 
-/* Opcode: Clear P1 P2 *
-**
-** Delete all contents of the database table or index whose root page
-** in the database file is given by P1.  But, unlike Destroy, do not
-** remove the table or index from the database file.
-**
-** The table being clear is in the main database file if P2==0.  If
-** P2==1 then the table to be clear is in the auxiliary database file
-** that is used to store tables create using CREATE TEMPORARY TABLE.
-**
-** See also: Destroy
+/*
+** Extract the user data from a sqlite3_context structure and return a
+** pointer to it.
 */
-case OP_Clear: {
-  assert( (p->btreeMask & (1<<pOp->p2))!=0 );
-  rc = sqlite3BtreeClearTable(db->aDb[pOp->p2].pBt, pOp->p1);
-  break;
+SQLITE_API void *sqlite3_user_data(sqlite3_context *p){
+  assert( p && p->pFunc );
+  return p->pFunc->pUserData;
 }
 
-/* Opcode: CreateTable P1 P2 * * *
-**
-** Allocate a new table in the main database file if P1==0 or in the
-** auxiliary database file if P1==1 or in an attached database if
-** P1>1.  Write the root page number of the new table into
-** register P2
-**
-** The difference between a table and an index is this:  A table must
-** have a 4-byte integer key and can have arbitrary data.  An index
-** has an arbitrary key but no data.
-**
-** See also: CreateIndex
-*/
-/* Opcode: CreateIndex P1 P2 * * *
-**
-** Allocate a new index in the main database file if P1==0 or in the
-** auxiliary database file if P1==1 or in an attached database if
-** P1>1.  Write the root page number of the new table into
-** register P2.
-**
-** See documentation on OP_CreateTable for additional information.
+/*
+** Extract the user data from a sqlite3_context structure and return a
+** pointer to it.
 */
-case OP_CreateIndex:            /* out2-prerelease */
-case OP_CreateTable: {          /* out2-prerelease */
-  int pgno;
-  int flags;
-  Db *pDb;
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pDb = &db->aDb[pOp->p1];
-  assert( pDb->pBt!=0 );
-  if( pOp->opcode==OP_CreateTable ){
-    /* flags = BTREE_INTKEY; */
-    flags = BTREE_LEAFDATA|BTREE_INTKEY;
-  }else{
-    flags = BTREE_ZERODATA;
-  }
-  rc = sqlite3BtreeCreateTable(pDb->pBt, &pgno, flags);
-  if( rc==SQLITE_OK ){
-    pOut->u.i = pgno;
-    MemSetTypeFlag(pOut, MEM_Int);
-  }
-  break;
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
+  assert( p && p->pFunc );
+  return p->s.db;
 }
 
-/* Opcode: ParseSchema P1 P2 * P4 *
-**
-** Read and parse all entries from the SQLITE_MASTER table of database P1
-** that match the WHERE clause P4.  P2 is the "force" flag.   Always do
-** the parsing if P2 is true.  If P2 is false, then this routine is a
-** no-op if the schema is not currently loaded.  In other words, if P2
-** is false, the SQLITE_MASTER table is only parsed if the rest of the
-** schema is already loaded into the symbol table.
-**
-** This opcode invokes the parser to create a new virtual machine,
-** then runs the new virtual machine.  It is thus a reentrant opcode.
+/*
+** The following is the implementation of an SQL function that always
+** fails with an error message stating that the function is used in the
+** wrong context.  The sqlite3_overload_function() API might construct
+** SQL function that use this routine so that the functions will exist
+** for name resolution but are actually overloaded by the xFindFunction
+** method of virtual tables.
 */
-case OP_ParseSchema: {
-  char *zSql;
-  int iDb = pOp->p1;
-  const char *zMaster;
-  InitData initData;
-
-  assert( iDb>=0 && iDb<db->nDb );
-  if( !pOp->p2 && !DbHasProperty(db, iDb, DB_SchemaLoaded) ){
-    break;
-  }
-  zMaster = SCHEMA_TABLE(iDb);
-  initData.db = db;
-  initData.iDb = pOp->p1;
-  initData.pzErrMsg = &p->zErrMsg;
-  zSql = sqlite3MPrintf(db,
-     "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
-     db->aDb[iDb].zName, zMaster, pOp->p4.z);
-  if( zSql==0 ) goto no_mem;
-  (void)sqlite3SafetyOff(db);
-  assert( db->init.busy==0 );
-  db->init.busy = 1;
-  assert( !db->mallocFailed );
-  rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
-  if( rc==SQLITE_ABORT ) rc = initData.rc;
-  sqlite3_free(zSql);
-  db->init.busy = 0;
-  (void)sqlite3SafetyOn(db);
-  if( rc==SQLITE_NOMEM ){
-    goto no_mem;
-  }
-  break;  
+SQLITE_PRIVATE void sqlite3InvalidFunction(
+  sqlite3_context *context,  /* The function calling context */
+  int NotUsed,               /* Number of arguments to the function */
+  sqlite3_value **NotUsed2   /* Value of each argument */
+){
+  const char *zName = context->pFunc->zName;
+  char *zErr;
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  zErr = sqlite3_mprintf(
+      "unable to use function %s in the requested context", zName);
+  sqlite3_result_error(context, zErr, -1);
+  sqlite3_free(zErr);
 }
 
-#if !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)
-/* Opcode: LoadAnalysis P1 * * * *
-**
-** Read the sqlite_stat1 table for database P1 and load the content
-** of that table into the internal index hash table.  This will cause
-** the analysis to be used when preparing all subsequent queries.
+/*
+** Allocate or return the aggregate context for a user function.  A new
+** context is allocated on the first call.  Subsequent calls return the
+** same context that was returned on prior calls.
 */
-case OP_LoadAnalysis: {
-  int iDb = pOp->p1;
-  assert( iDb>=0 && iDb<db->nDb );
-  rc = sqlite3AnalysisLoad(db, iDb);
-  break;  
+SQLITE_API void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){
+  Mem *pMem;
+  assert( p && p->pFunc && p->pFunc->xStep );
+  assert( sqlite3_mutex_held(p->s.db->mutex) );
+  pMem = p->pMem;
+  if( (pMem->flags & MEM_Agg)==0 ){
+    if( nByte==0 ){
+      sqlite3VdbeMemReleaseExternal(pMem);
+      pMem->flags = MEM_Null;
+      pMem->z = 0;
+    }else{
+      sqlite3VdbeMemGrow(pMem, nByte, 0);
+      pMem->flags = MEM_Agg;
+      pMem->u.pDef = p->pFunc;
+      if( pMem->z ){
+        memset(pMem->z, 0, nByte);
+      }
+    }
+  }
+  return (void*)pMem->z;
 }
-#endif /* !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)  */
 
-/* Opcode: DropTable P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the table named P4 in database P1.  This is called after a table
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
+/*
+** Return the auxilary data pointer, if any, for the iArg'th argument to
+** the user-function defined by pCtx.
 */
-case OP_DropTable: {
-  sqlite3UnlinkAndDeleteTable(db, pOp->p1, pOp->p4.z);
-  break;
-}
+SQLITE_API void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
+  VdbeFunc *pVdbeFunc;
 
-/* Opcode: DropIndex P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the index named P4 in database P1.  This is called after an index
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
-*/
-case OP_DropIndex: {
-  sqlite3UnlinkAndDeleteIndex(db, pOp->p1, pOp->p4.z);
-  break;
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  pVdbeFunc = pCtx->pVdbeFunc;
+  if( !pVdbeFunc || iArg>=pVdbeFunc->nAux || iArg<0 ){
+    return 0;
+  }
+  return pVdbeFunc->apAux[iArg].pAux;
 }
 
-/* Opcode: DropTrigger P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the trigger named P4 in database P1.  This is called after a trigger
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
+/*
+** Set the auxilary data pointer and delete function, for the iArg'th
+** argument to the user-function defined by pCtx. Any previous value is
+** deleted by calling the delete function specified when it was set.
 */
-case OP_DropTrigger: {
-  sqlite3UnlinkAndDeleteTrigger(db, pOp->p1, pOp->p4.z);
-  break;
-}
-
+SQLITE_API void sqlite3_set_auxdata(
+  sqlite3_context *pCtx, 
+  int iArg, 
+  void *pAux, 
+  void (*xDelete)(void*)
+){
+  struct AuxData *pAuxData;
+  VdbeFunc *pVdbeFunc;
+  if( iArg<0 ) goto failed;
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
-/* Opcode: IntegrityCk P1 P2 P3 * P5
-**
-** Do an analysis of the currently open database.  Store in
-** register P1 the text of an error message describing any problems.
-** If no problems are found, store a NULL in register P1.
-**
-** The register P3 contains the maximum number of allowed errors.
-** At most reg(P3) errors will be reported.
-** In other words, the analysis stops as soon as reg(P1) errors are 
-** seen.  Reg(P1) is updated with the number of errors remaining.
-**
-** The root page numbers of all tables in the database are integer
-** stored in reg(P1), reg(P1+1), reg(P1+2), ....  There are P2 tables
-** total.
-**
-** If P5 is not zero, the check is done on the auxiliary database
-** file, not the main database file.
-**
-** This opcode is used to implement the integrity_check pragma.
-*/
-case OP_IntegrityCk: {
-  int nRoot;      /* Number of tables to check.  (Number of root pages.) */
-  int *aRoot;     /* Array of rootpage numbers for tables to be checked */
-  int j;          /* Loop counter */
-  int nErr;       /* Number of errors reported */
-  char *z;        /* Text of the error report */
-  Mem *pnErr;     /* Register keeping track of errors remaining */
-  
-  nRoot = pOp->p2;
-  assert( nRoot>0 );
-  aRoot = sqlite3_malloc( sizeof(int)*(nRoot+1) );
-  if( aRoot==0 ) goto no_mem;
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pnErr = &p->aMem[pOp->p3];
-  assert( (pnErr->flags & MEM_Int)!=0 );
-  assert( (pnErr->flags & (MEM_Str|MEM_Blob))==0 );
-  pIn1 = &p->aMem[pOp->p1];
-  for(j=0; j<nRoot; j++){
-    aRoot[j] = sqlite3VdbeIntValue(&pIn1[j]);
+  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
+  pVdbeFunc = pCtx->pVdbeFunc;
+  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
+    int nAux = (pVdbeFunc ? pVdbeFunc->nAux : 0);
+    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
+    pVdbeFunc = sqlite3DbRealloc(pCtx->s.db, pVdbeFunc, nMalloc);
+    if( !pVdbeFunc ){
+      goto failed;
+    }
+    pCtx->pVdbeFunc = pVdbeFunc;
+    memset(&pVdbeFunc->apAux[nAux], 0, sizeof(struct AuxData)*(iArg+1-nAux));
+    pVdbeFunc->nAux = iArg+1;
+    pVdbeFunc->pFunc = pCtx->pFunc;
   }
-  aRoot[j] = 0;
-  assert( pOp->p5<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p5))!=0 );
-  z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, aRoot, nRoot,
-                                 pnErr->u.i, &nErr);
-  pnErr->u.i -= nErr;
-  sqlite3VdbeMemSetNull(pIn1);
-  if( nErr==0 ){
-    assert( z==0 );
-  }else{
-    sqlite3VdbeMemSetStr(pIn1, z, -1, SQLITE_UTF8, sqlite3_free);
+
+  pAuxData = &pVdbeFunc->apAux[iArg];
+  if( pAuxData->pAux && pAuxData->xDelete ){
+    pAuxData->xDelete(pAuxData->pAux);
   }
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  sqlite3VdbeChangeEncoding(pIn1, encoding);
-  sqlite3_free(aRoot);
-  break;
-}
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
+  pAuxData->pAux = pAux;
+  pAuxData->xDelete = xDelete;
+  return;
 
-/* Opcode: FifoWrite P1 * * * *
-**
-** Write the integer from register P1 into the Fifo.
-*/
-case OP_FifoWrite: {        /* in1 */
-  if( sqlite3VdbeFifoPush(&p->sFifo, sqlite3VdbeIntValue(pIn1))==SQLITE_NOMEM ){
-    goto no_mem;
+failed:
+  if( xDelete ){
+    xDelete(pAux);
   }
-  break;
 }
 
-/* Opcode: FifoRead P1 P2 * * *
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Return the number of times the Step function of a aggregate has been 
+** called.
 **
-** Attempt to read a single integer from the Fifo.  Store that
-** integer in register P1.
-** 
-** If the Fifo is empty jump to P2.
+** This function is deprecated.  Do not use it for new code.  It is
+** provide only to avoid breaking legacy code.  New aggregate function
+** implementations should keep their own counts within their aggregate
+** context.
 */
-case OP_FifoRead: {         /* jump */
-  CHECK_FOR_INTERRUPT;
-  assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  pOut = &p->aMem[pOp->p1];
-  MemSetTypeFlag(pOut, MEM_Int);
-  if( sqlite3VdbeFifoPop(&p->sFifo, &pOut->u.i)==SQLITE_DONE ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-#ifndef SQLITE_OMIT_TRIGGER
-/* Opcode: ContextPush * * * 
-**
-** Save the current Vdbe context such that it can be restored by a ContextPop
-** opcode. The context stores the last insert row id, the last statement change
-** count, and the current statement change count.
-*/
-case OP_ContextPush: {
-  int i = p->contextStackTop++;
-  Context *pContext;
-
-  assert( i>=0 );
-  /* FIX ME: This should be allocated as part of the vdbe at compile-time */
-  if( i>=p->contextStackDepth ){
-    p->contextStackDepth = i+1;
-    p->contextStack = sqlite3DbReallocOrFree(db, p->contextStack,
-                                          sizeof(Context)*(i+1));
-    if( p->contextStack==0 ) goto no_mem;
-  }
-  pContext = &p->contextStack[i];
-  pContext->lastRowid = db->lastRowid;
-  pContext->nChange = p->nChange;
-  pContext->sFifo = p->sFifo;
-  sqlite3VdbeFifoInit(&p->sFifo);
-  break;
+SQLITE_API int sqlite3_aggregate_count(sqlite3_context *p){
+  assert( p && p->pMem && p->pFunc && p->pFunc->xStep );
+  return p->pMem->n;
 }
+#endif
 
-/* Opcode: ContextPop * * * 
-**
-** Restore the Vdbe context to the state it was in when contextPush was last
-** executed. The context stores the last insert row id, the last statement
-** change count, and the current statement change count.
+/*
+** Return the number of columns in the result set for the statement pStmt.
 */
-case OP_ContextPop: {
-  Context *pContext = &p->contextStack[--p->contextStackTop];
-  assert( p->contextStackTop>=0 );
-  db->lastRowid = pContext->lastRowid;
-  p->nChange = pContext->nChange;
-  sqlite3VdbeFifoClear(&p->sFifo);
-  p->sFifo = pContext->sFifo;
-  break;
+SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt){
+  Vdbe *pVm = (Vdbe *)pStmt;
+  return pVm ? pVm->nResColumn : 0;
 }
-#endif /* #ifndef SQLITE_OMIT_TRIGGER */
 
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-/* Opcode: MemMax P1 P2 * * *
-**
-** Set the value of register P1 to the maximum of its current value
-** and the value in register P2.
-**
-** This instruction throws an error if the memory cell is not initially
-** an integer.
+/*
+** Return the number of values available from the current row of the
+** currently executing statement pStmt.
 */
-case OP_MemMax: {        /* in1, in2 */
-  sqlite3VdbeMemIntegerify(pIn1);
-  sqlite3VdbeMemIntegerify(pIn2);
-  if( pIn1->u.i<pIn2->u.i){
-    pIn1->u.i = pIn2->u.i;
-  }
-  break;
+SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt){
+  Vdbe *pVm = (Vdbe *)pStmt;
+  if( pVm==0 || pVm->pResultSet==0 ) return 0;
+  return pVm->nResColumn;
 }
-#endif /* SQLITE_OMIT_AUTOINCREMENT */
 
-/* Opcode: IfPos P1 P2 * * *
-**
-** If the value of register P1 is 1 or greater, jump to P2.
-**
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
+
+/*
+** Check to see if column iCol of the given statement is valid.  If
+** it is, return a pointer to the Mem for the value of that column.
+** If iCol is not valid, return a pointer to a Mem which has a value
+** of NULL.
 */
-case OP_IfPos: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i>0 ){
-     pc = pOp->p2 - 1;
+static Mem *columnMem(sqlite3_stmt *pStmt, int i){
+  Vdbe *pVm;
+  int vals;
+  Mem *pOut;
+
+  pVm = (Vdbe *)pStmt;
+  if( pVm && pVm->pResultSet!=0 && i<pVm->nResColumn && i>=0 ){
+    sqlite3_mutex_enter(pVm->db->mutex);
+    vals = sqlite3_data_count(pStmt);
+    pOut = &pVm->pResultSet[i];
+  }else{
+    /* If the value passed as the second argument is out of range, return
+    ** a pointer to the following static Mem object which contains the
+    ** value SQL NULL. Even though the Mem structure contains an element
+    ** of type i64, on certain architecture (x86) with certain compiler
+    ** switches (-Os), gcc may align this Mem object on a 4-byte boundary
+    ** instead of an 8-byte one. This all works fine, except that when
+    ** running with SQLITE_DEBUG defined the SQLite code sometimes assert()s
+    ** that a Mem structure is located on an 8-byte boundary. To prevent
+    ** this assert() from failing, when building with SQLITE_DEBUG defined
+    ** using gcc, force nullMem to be 8-byte aligned using the magical
+    ** __attribute__((aligned(8))) macro.  */
+    static const Mem nullMem 
+#if defined(SQLITE_DEBUG) && defined(__GNUC__)
+      __attribute__((aligned(8))) 
+#endif
+      = {{0}, (double)0, 0, "", 0, MEM_Null, SQLITE_NULL, 0, 0, 0 };
+
+    if( pVm && ALWAYS(pVm->db) ){
+      sqlite3_mutex_enter(pVm->db->mutex);
+      sqlite3Error(pVm->db, SQLITE_RANGE, 0);
+    }
+    pOut = (Mem*)&nullMem;
   }
-  break;
+  return pOut;
 }
 
-/* Opcode: IfNeg P1 P2 * * *
+/*
+** This function is called after invoking an sqlite3_value_XXX function on a 
+** column value (i.e. a value returned by evaluating an SQL expression in the
+** select list of a SELECT statement) that may cause a malloc() failure. If 
+** malloc() has failed, the threads mallocFailed flag is cleared and the result
+** code of statement pStmt set to SQLITE_NOMEM.
 **
-** If the value of register P1 is less than zero, jump to P2. 
+** Specifically, this is called from within:
 **
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
+**     sqlite3_column_int()
+**     sqlite3_column_int64()
+**     sqlite3_column_text()
+**     sqlite3_column_text16()
+**     sqlite3_column_real()
+**     sqlite3_column_bytes()
+**     sqlite3_column_bytes16()
+**
+** But not for sqlite3_column_blob(), which never calls malloc().
 */
-case OP_IfNeg: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i<0 ){
-     pc = pOp->p2 - 1;
+static void columnMallocFailure(sqlite3_stmt *pStmt)
+{
+  /* If malloc() failed during an encoding conversion within an
+  ** sqlite3_column_XXX API, then set the return code of the statement to
+  ** SQLITE_NOMEM. The next call to _step() (if any) will return SQLITE_ERROR
+  ** and _finalize() will return NOMEM.
+  */
+  Vdbe *p = (Vdbe *)pStmt;
+  if( p ){
+    p->rc = sqlite3ApiExit(p->db, p->rc);
+    sqlite3_mutex_leave(p->db->mutex);
   }
-  break;
 }
 
-/* Opcode: IfZero P1 P2 * * *
-**
-** If the value of register P1 is exactly 0, jump to P2. 
-**
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
+/**************************** sqlite3_column_  *******************************
+** The following routines are used to access elements of the current row
+** in the result set.
 */
-case OP_IfZero: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i==0 ){
-     pc = pOp->p2 - 1;
+SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt *pStmt, int i){
+  const void *val;
+  val = sqlite3_value_blob( columnMem(pStmt,i) );
+  /* Even though there is no encoding conversion, value_blob() might
+  ** need to call malloc() to expand the result of a zeroblob() 
+  ** expression. 
+  */
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API int sqlite3_column_bytes(sqlite3_stmt *pStmt, int i){
+  int val = sqlite3_value_bytes( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt *pStmt, int i){
+  int val = sqlite3_value_bytes16( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API double sqlite3_column_double(sqlite3_stmt *pStmt, int i){
+  double val = sqlite3_value_double( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API int sqlite3_column_int(sqlite3_stmt *pStmt, int i){
+  int val = sqlite3_value_int( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API sqlite_int64 sqlite3_column_int64(sqlite3_stmt *pStmt, int i){
+  sqlite_int64 val = sqlite3_value_int64( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt *pStmt, int i){
+  const unsigned char *val = sqlite3_value_text( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt *pStmt, int i){
+  Mem *pOut = columnMem(pStmt, i);
+  if( pOut->flags&MEM_Static ){
+    pOut->flags &= ~MEM_Static;
+    pOut->flags |= MEM_Ephem;
   }
-  break;
+  columnMallocFailure(pStmt);
+  return (sqlite3_value *)pOut;
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt *pStmt, int i){
+  const void *val = sqlite3_value_text16( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return val;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+SQLITE_API int sqlite3_column_type(sqlite3_stmt *pStmt, int i){
+  int iType = sqlite3_value_type( columnMem(pStmt,i) );
+  columnMallocFailure(pStmt);
+  return iType;
 }
 
-/* Opcode: AggStep * P2 P3 P4 P5
-**
-** Execute the step function for an aggregate.  The
-** function has P5 arguments.   P4 is a pointer to the FuncDef
-** structure that specifies the function.  Use register
-** P3 as the accumulator.
-**
-** The P5 arguments are taken from register P2 and its
-** successors.
+/* The following function is experimental and subject to change or
+** removal */
+/*int sqlite3_column_numeric_type(sqlite3_stmt *pStmt, int i){
+**  return sqlite3_value_numeric_type( columnMem(pStmt,i) );
+**}
 */
-case OP_AggStep: {
-  int n = pOp->p5;
-  int i;
-  Mem *pMem, *pRec;
-  sqlite3_context ctx;
-  sqlite3_value **apVal;
-
-  assert( n>=0 );
-  pRec = &p->aMem[pOp->p2];
-  apVal = p->apArg;
-  assert( apVal || n==0 );
-  for(i=0; i<n; i++, pRec++){
-    apVal[i] = pRec;
-    storeTypeInfo(pRec, encoding);
-  }
-  ctx.pFunc = pOp->p4.pFunc;
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  ctx.pMem = pMem = &p->aMem[pOp->p3];
-  pMem->n++;
-  ctx.s.flags = MEM_Null;
-  ctx.s.z = 0;
-  ctx.s.zMalloc = 0;
-  ctx.s.xDel = 0;
-  ctx.s.db = db;
-  ctx.isError = 0;
-  ctx.pColl = 0;
-  if( ctx.pFunc->needCollSeq ){
-    assert( pOp>p->aOp );
-    assert( pOp[-1].p4type==P4_COLLSEQ );
-    assert( pOp[-1].opcode==OP_CollSeq );
-    ctx.pColl = pOp[-1].p4.pColl;
-  }
-  (ctx.pFunc->xStep)(&ctx, n, apVal);
-  if( ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, sqlite3_value_text(&ctx.s), (char*)0);
-    rc = ctx.isError;
-  }
-  sqlite3VdbeMemRelease(&ctx.s);
-  break;
-}
 
-/* Opcode: AggFinal P1 P2 * P4 *
+/*
+** Convert the N-th element of pStmt->pColName[] into a string using
+** xFunc() then return that string.  If N is out of range, return 0.
 **
-** Execute the finalizer function for an aggregate.  P1 is
-** the memory location that is the accumulator for the aggregate.
+** There are up to 5 names for each column.  useType determines which
+** name is returned.  Here are the names:
 **
-** P2 is the number of arguments that the step function takes and
-** P4 is a pointer to the FuncDef for this function.  The P2
-** argument is not used by this opcode.  It is only there to disambiguate
-** functions that can take varying numbers of arguments.  The
-** P4 argument is only needed for the degenerate case where
-** the step function was not previously called.
+**    0      The column name as it should be displayed for output
+**    1      The datatype name for the column
+**    2      The name of the database that the column derives from
+**    3      The name of the table that the column derives from
+**    4      The name of the table column that the result column derives from
+**
+** If the result is not a simple column reference (if it is an expression
+** or a constant) then useTypes 2, 3, and 4 return NULL.
 */
-case OP_AggFinal: {
-  Mem *pMem;
-  assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  pMem = &p->aMem[pOp->p1];
-  assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
-  rc = sqlite3VdbeMemFinalize(pMem, pOp->p4.pFunc);
-  if( rc==SQLITE_ERROR ){
-    sqlite3SetString(&p->zErrMsg, sqlite3_value_text(pMem), (char*)0);
-  }
-  sqlite3VdbeChangeEncoding(pMem, encoding);
-  UPDATE_MAX_BLOBSIZE(pMem);
-  if( sqlite3VdbeMemTooBig(pMem) ){
-    goto too_big;
+static const void *columnName(
+  sqlite3_stmt *pStmt,
+  int N,
+  const void *(*xFunc)(Mem*),
+  int useType
+){
+  const void *ret = 0;
+  Vdbe *p = (Vdbe *)pStmt;
+  int n;
+  sqlite3 *db = p->db;
+  
+  assert( db!=0 );
+  n = sqlite3_column_count(pStmt);
+  if( N<n && N>=0 ){
+    N += useType*n;
+    sqlite3_mutex_enter(db->mutex);
+    assert( db->mallocFailed==0 );
+    ret = xFunc(&p->aColName[N]);
+     /* A malloc may have failed inside of the xFunc() call. If this
+    ** is the case, clear the mallocFailed flag and return NULL.
+    */
+    if( db->mallocFailed ){
+      db->mallocFailed = 0;
+      ret = 0;
+    }
+    sqlite3_mutex_leave(db->mutex);
   }
-  break;
+  return ret;
 }
 
-
-#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
-/* Opcode: Vacuum * * * * *
-**
-** Vacuum the entire database.  This opcode will cause other virtual
-** machines to be created and run.  It may not be called from within
-** a transaction.
+/*
+** Return the name of the Nth column of the result set returned by SQL
+** statement pStmt.
 */
-case OP_Vacuum: {
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse; 
-  rc = sqlite3RunVacuum(&p->zErrMsg, db);
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-  break;
+SQLITE_API const char *sqlite3_column_name(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_NAME);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_NAME);
 }
 #endif
 
-#if !defined(SQLITE_OMIT_AUTOVACUUM)
-/* Opcode: IncrVacuum P1 P2 * * *
-**
-** Perform a single step of the incremental vacuum procedure on
-** the P1 database. If the vacuum has finished, jump to instruction
-** P2. Otherwise, fall through to the next instruction.
+/*
+** Constraint:  If you have ENABLE_COLUMN_METADATA then you must
+** not define OMIT_DECLTYPE.
 */
-case OP_IncrVacuum: {        /* jump */
-  Btree *pBt;
-
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pBt = db->aDb[pOp->p1].pBt;
-  rc = sqlite3BtreeIncrVacuum(pBt);
-  if( rc==SQLITE_DONE ){
-    pc = pOp->p2 - 1;
-    rc = SQLITE_OK;
-  }
-  break;
-}
+#if defined(SQLITE_OMIT_DECLTYPE) && defined(SQLITE_ENABLE_COLUMN_METADATA)
+# error "Must not define both SQLITE_OMIT_DECLTYPE \
+         and SQLITE_ENABLE_COLUMN_METADATA"
 #endif
 
-/* Opcode: Expire P1 * * * *
-**
-** Cause precompiled statements to become expired. An expired statement
-** fails with an error code of SQLITE_SCHEMA if it is ever executed 
-** (via sqlite3_step()).
-** 
-** If P1 is 0, then all SQL statements become expired. If P1 is non-zero,
-** then only the currently executing statement is affected. 
+#ifndef SQLITE_OMIT_DECLTYPE
+/*
+** Return the column declaration type (if applicable) of the 'i'th column
+** of the result set of SQL statement pStmt.
 */
-case OP_Expire: {
-  if( !pOp->p1 ){
-    sqlite3ExpirePreparedStatements(db);
-  }else{
-    p->expired = 1;
-  }
-  break;
+SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DECLTYPE);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DECLTYPE);
 }
+#endif /* SQLITE_OMIT_UTF16 */
+#endif /* SQLITE_OMIT_DECLTYPE */
 
-#ifndef SQLITE_OMIT_SHARED_CACHE
-/* Opcode: TableLock P1 P2 P3 P4 *
-**
-** Obtain a lock on a particular table. This instruction is only used when
-** the shared-cache feature is enabled. 
-**
-** If P1 is  the index of the database in sqlite3.aDb[] of the database
-** on which the lock is acquired.  A readlock is obtained if P3==0 or
-** a write lock if P3==1.
-**
-** P2 contains the root-page of the table to lock.
-**
-** P4 contains a pointer to the name of the table being locked. This is only
-** used to generate an error message if the lock cannot be obtained.
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+/*
+** Return the name of the database from which a result column derives.
+** NULL is returned if the result column is an expression or constant or
+** anything else which is not an unabiguous reference to a database column.
 */
-case OP_TableLock: {
-  int p1 = pOp->p1; 
-  u8 isWriteLock = pOp->p3;
-  assert( p1>=0 && p1<db->nDb );
-  assert( (p->btreeMask & (1<<p1))!=0 );
-  assert( isWriteLock==0 || isWriteLock==1 );
-  rc = sqlite3BtreeLockTable(db->aDb[p1].pBt, pOp->p2, isWriteLock);
-  if( rc==SQLITE_LOCKED ){
-    const char *z = pOp->p4.z;
-    sqlite3SetString(&p->zErrMsg, "database table is locked: ", z, (char*)0);
-  }
-  break;
+SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DATABASE);
 }
-#endif /* SQLITE_OMIT_SHARED_CACHE */
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DATABASE);
+}
+#endif /* SQLITE_OMIT_UTF16 */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VBegin * * * P4 *
-**
-** P4 a pointer to an sqlite3_vtab structure. Call the xBegin method 
-** for that table.
+/*
+** Return the name of the table from which a result column derives.
+** NULL is returned if the result column is an expression or constant or
+** anything else which is not an unabiguous reference to a database column.
 */
-case OP_VBegin: {
-  rc = sqlite3VtabBegin(db, pOp->p4.pVtab);
-  break;
+SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_TABLE);
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_TABLE);
+}
+#endif /* SQLITE_OMIT_UTF16 */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VCreate P1 * * P4 *
-**
-** P4 is the name of a virtual table in database P1. Call the xCreate method
-** for that table.
+/*
+** Return the name of the table column from which a result column derives.
+** NULL is returned if the result column is an expression or constant or
+** anything else which is not an unabiguous reference to a database column.
 */
-case OP_VCreate: {
-  rc = sqlite3VtabCallCreate(db, pOp->p1, pOp->p4.z, &p->zErrMsg);
-  break;
+SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_COLUMN);
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt *pStmt, int N){
+  return columnName(
+      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_COLUMN);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+#endif /* SQLITE_ENABLE_COLUMN_METADATA */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VDestroy P1 * * P4 *
+
+/******************************* sqlite3_bind_  ***************************
+** 
+** Routines used to attach values to wildcards in a compiled SQL statement.
+*/
+/*
+** Unbind the value bound to variable i in virtual machine p. This is the 
+** the same as binding a NULL value to the column. If the "i" parameter is
+** out of range, then SQLITE_RANGE is returned. Othewise SQLITE_OK.
 **
-** P4 is the name of a virtual table in database P1.  Call the xDestroy method
-** of that table.
+** A successful evaluation of this routine acquires the mutex on p.
+** the mutex is released if any kind of error occurs.
+**
+** The error code stored in database p->db is overwritten with the return
+** value in any case.
 */
-case OP_VDestroy: {
-  p->inVtabMethod = 2;
-  rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p4.z);
-  p->inVtabMethod = 0;
-  break;
+static int vdbeUnbind(Vdbe *p, int i){
+  Mem *pVar;
+  if( p==0 ) return SQLITE_MISUSE;
+  sqlite3_mutex_enter(p->db->mutex);
+  if( p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
+    sqlite3Error(p->db, SQLITE_MISUSE, 0);
+    sqlite3_mutex_leave(p->db->mutex);
+    return SQLITE_MISUSE;
+  }
+  if( i<1 || i>p->nVar ){
+    sqlite3Error(p->db, SQLITE_RANGE, 0);
+    sqlite3_mutex_leave(p->db->mutex);
+    return SQLITE_RANGE;
+  }
+  i--;
+  pVar = &p->aVar[i];
+  sqlite3VdbeMemRelease(pVar);
+  pVar->flags = MEM_Null;
+  sqlite3Error(p->db, SQLITE_OK, 0);
+  return SQLITE_OK;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VOpen P1 * * P4 *
-**
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** P1 is a cursor number.  This opcode opens a cursor to the virtual
-** table and stores that cursor in P1.
+/*
+** Bind a text or BLOB value.
 */
-case OP_VOpen: {
-  Cursor *pCur = 0;
-  sqlite3_vtab_cursor *pVtabCursor = 0;
-
-  sqlite3_vtab *pVtab = pOp->p4.pVtab;
-  sqlite3_module *pModule = (sqlite3_module *)pVtab->pModule;
-
-  assert(pVtab && pModule);
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pModule->xOpen(pVtab, &pVtabCursor);
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-  if( SQLITE_OK==rc ){
-    /* Initialise sqlite3_vtab_cursor base class */
-    pVtabCursor->pVtab = pVtab;
+static int bindText(
+  sqlite3_stmt *pStmt,   /* The statement to bind against */
+  int i,                 /* Index of the parameter to bind */
+  const void *zData,     /* Pointer to the data to be bound */
+  int nData,             /* Number of bytes of data to be bound */
+  void (*xDel)(void*),   /* Destructor for the data */
+  u8 encoding            /* Encoding for the data */
+){
+  Vdbe *p = (Vdbe *)pStmt;
+  Mem *pVar;
+  int rc;
 
-    /* Initialise vdbe cursor object */
-    pCur = allocateCursor(p, pOp->p1, &pOp[-1], -1, 0);
-    if( pCur ){
-      pCur->pVtabCursor = pVtabCursor;
-      pCur->pModule = pVtabCursor->pVtab->pModule;
-    }else{
-      db->mallocFailed = 1;
-      pModule->xClose(pVtabCursor);
+  rc = vdbeUnbind(p, i);
+  if( rc==SQLITE_OK ){
+    if( zData!=0 ){
+      pVar = &p->aVar[i-1];
+      rc = sqlite3VdbeMemSetStr(pVar, zData, nData, encoding, xDel);
+      if( rc==SQLITE_OK && encoding!=0 ){
+        rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
+      }
+      sqlite3Error(p->db, rc, 0);
+      rc = sqlite3ApiExit(p->db, rc);
     }
+    sqlite3_mutex_leave(p->db->mutex);
   }
-  break;
+  return rc;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VFilter P1 P2 P3 P4 *
-**
-** P1 is a cursor opened using VOpen.  P2 is an address to jump to if
-** the filtered result set is empty.
-**
-** P4 is either NULL or a string that was generated by the xBestIndex
-** method of the module.  The interpretation of the P4 string is left
-** to the module implementation.
-**
-** This opcode invokes the xFilter method on the virtual table specified
-** by P1.  The integer query plan parameter to xFilter is stored in register
-** P3. Register P3+1 stores the argc parameter to be passed to the
-** xFilter method. Registers P3+2..P3+1+argc are the argc additional
-** parametersneath additional parameters which are passed to
-** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
-**
-** A jump is made to P2 if the result set after filtering would be empty.
-*/
-case OP_VFilter: {   /* jump */
-  int nArg;
-  int iQuery;
-  const sqlite3_module *pModule;
-  Mem *pQuery = &p->aMem[pOp->p3];
-  Mem *pArgc = &pQuery[1];
-
-  Cursor *pCur = p->apCsr[pOp->p1];
-
-  REGISTER_TRACE(pOp->p3, pQuery);
-  assert( pCur->pVtabCursor );
-  pModule = pCur->pVtabCursor->pVtab->pModule;
 
-  /* Grab the index number and argc parameters */
-  assert( (pQuery->flags&MEM_Int)!=0 && pArgc->flags==MEM_Int );
-  nArg = pArgc->u.i;
-  iQuery = pQuery->u.i;
 
-  /* Invoke the xFilter method */
-  {
-    int res = 0;
-    int i;
-    Mem **apArg = p->apArg;
-    for(i = 0; i<nArg; i++){
-      apArg[i] = &pArgc[i+1];
-      storeTypeInfo(apArg[i], 0);
+/*
+** Bind a blob value to an SQL statement variable.
+*/
+SQLITE_API int sqlite3_bind_blob(
+  sqlite3_stmt *pStmt, 
+  int i, 
+  const void *zData, 
+  int nData, 
+  void (*xDel)(void*)
+){
+  return bindText(pStmt, i, zData, nData, xDel, 0);
+}
+SQLITE_API int sqlite3_bind_double(sqlite3_stmt *pStmt, int i, double rValue){
+  int rc;
+  Vdbe *p = (Vdbe *)pStmt;
+  rc = vdbeUnbind(p, i);
+  if( rc==SQLITE_OK ){
+    sqlite3VdbeMemSetDouble(&p->aVar[i-1], rValue);
+    sqlite3_mutex_leave(p->db->mutex);
+  }
+  return rc;
+}
+SQLITE_API int sqlite3_bind_int(sqlite3_stmt *p, int i, int iValue){
+  return sqlite3_bind_int64(p, i, (i64)iValue);
+}
+SQLITE_API int sqlite3_bind_int64(sqlite3_stmt *pStmt, int i, sqlite_int64 iValue){
+  int rc;
+  Vdbe *p = (Vdbe *)pStmt;
+  rc = vdbeUnbind(p, i);
+  if( rc==SQLITE_OK ){
+    sqlite3VdbeMemSetInt64(&p->aVar[i-1], iValue);
+    sqlite3_mutex_leave(p->db->mutex);
+  }
+  return rc;
+}
+SQLITE_API int sqlite3_bind_null(sqlite3_stmt *pStmt, int i){
+  int rc;
+  Vdbe *p = (Vdbe*)pStmt;
+  rc = vdbeUnbind(p, i);
+  if( rc==SQLITE_OK ){
+    sqlite3_mutex_leave(p->db->mutex);
+  }
+  return rc;
+}
+SQLITE_API int sqlite3_bind_text( 
+  sqlite3_stmt *pStmt, 
+  int i, 
+  const char *zData, 
+  int nData, 
+  void (*xDel)(void*)
+){
+  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF8);
+}
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API int sqlite3_bind_text16(
+  sqlite3_stmt *pStmt, 
+  int i, 
+  const void *zData, 
+  int nData, 
+  void (*xDel)(void*)
+){
+  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF16NATIVE);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+SQLITE_API int sqlite3_bind_value(sqlite3_stmt *pStmt, int i, const sqlite3_value *pValue){
+  int rc;
+  switch( pValue->type ){
+    case SQLITE_INTEGER: {
+      rc = sqlite3_bind_int64(pStmt, i, pValue->u.i);
+      break;
     }
-
-    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-    p->inVtabMethod = 1;
-    rc = pModule->xFilter(pCur->pVtabCursor, iQuery, pOp->p4.z, nArg, apArg);
-    p->inVtabMethod = 0;
-    if( rc==SQLITE_OK ){
-      res = pModule->xEof(pCur->pVtabCursor);
+    case SQLITE_FLOAT: {
+      rc = sqlite3_bind_double(pStmt, i, pValue->r);
+      break;
     }
-    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-
-    if( res ){
-      pc = pOp->p2 - 1;
+    case SQLITE_BLOB: {
+      if( pValue->flags & MEM_Zero ){
+        rc = sqlite3_bind_zeroblob(pStmt, i, pValue->u.nZero);
+      }else{
+        rc = sqlite3_bind_blob(pStmt, i, pValue->z, pValue->n,SQLITE_TRANSIENT);
+      }
+      break;
+    }
+    case SQLITE_TEXT: {
+      rc = bindText(pStmt,i,  pValue->z, pValue->n, SQLITE_TRANSIENT,
+                              pValue->enc);
+      break;
+    }
+    default: {
+      rc = sqlite3_bind_null(pStmt, i);
+      break;
     }
   }
-  pCur->nullRow = 0;
-
-  break;
+  return rc;
+}
+SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt *pStmt, int i, int n){
+  int rc;
+  Vdbe *p = (Vdbe *)pStmt;
+  rc = vdbeUnbind(p, i);
+  if( rc==SQLITE_OK ){
+    sqlite3VdbeMemSetZeroBlob(&p->aVar[i-1], n);
+    sqlite3_mutex_leave(p->db->mutex);
+  }
+  return rc;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VRowid P1 P2 * * *
-**
-** Store into register P2  the rowid of
-** the virtual-table that the P1 cursor is pointing to.
+/*
+** Return the number of wildcards that can be potentially bound to.
+** This routine is added to support DBD::SQLite.  
 */
-case OP_VRowid: {             /* out2-prerelease */
-  const sqlite3_module *pModule;
-  sqlite_int64 iRow;
-  Cursor *pCur = p->apCsr[pOp->p1];
+SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt *pStmt){
+  Vdbe *p = (Vdbe*)pStmt;
+  return p ? p->nVar : 0;
+}
 
-  assert( pCur->pVtabCursor );
-  if( pCur->nullRow ){
-    break;
+/*
+** Create a mapping from variable numbers to variable names
+** in the Vdbe.azVar[] array, if such a mapping does not already
+** exist.
+*/
+static void createVarMap(Vdbe *p){
+  if( !p->okVar ){
+    int j;
+    Op *pOp;
+    sqlite3_mutex_enter(p->db->mutex);
+    /* The race condition here is harmless.  If two threads call this
+    ** routine on the same Vdbe at the same time, they both might end
+    ** up initializing the Vdbe.azVar[] array.  That is a little extra
+    ** work but it results in the same answer.
+    */
+    for(j=0, pOp=p->aOp; j<p->nOp; j++, pOp++){
+      if( pOp->opcode==OP_Variable ){
+        assert( pOp->p1>0 && pOp->p1<=p->nVar );
+        p->azVar[pOp->p1-1] = pOp->p4.z;
+      }
+    }
+    p->okVar = 1;
+    sqlite3_mutex_leave(p->db->mutex);
   }
-  pModule = pCur->pVtabCursor->pVtab->pModule;
-  assert( pModule->xRowid );
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pModule->xRowid(pCur->pVtabCursor, &iRow);
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-  MemSetTypeFlag(pOut, MEM_Int);
-  pOut->u.i = iRow;
-  break;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VColumn P1 P2 P3 * *
+/*
+** Return the name of a wildcard parameter.  Return NULL if the index
+** is out of range or if the wildcard is unnamed.
 **
-** Store the value of the P2-th column of
-** the row of the virtual-table that the 
-** P1 cursor is pointing to into register P3.
+** The result is always UTF-8.
 */
-case OP_VColumn: {
-  const sqlite3_module *pModule;
-  Mem *pDest;
-  sqlite3_context sContext;
-
-  Cursor *pCur = p->apCsr[pOp->p1];
-  assert( pCur->pVtabCursor );
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pDest = &p->aMem[pOp->p3];
-  if( pCur->nullRow ){
-    sqlite3VdbeMemSetNull(pDest);
-    break;
-  }
-  pModule = pCur->pVtabCursor->pVtab->pModule;
-  assert( pModule->xColumn );
-  memset(&sContext, 0, sizeof(sContext));
-
-  /* The output cell may already have a buffer allocated. Move
-  ** the current contents to sContext.s so in case the user-function 
-  ** can use the already allocated buffer instead of allocating a 
-  ** new one.
-  */
-  sqlite3VdbeMemMove(&sContext.s, pDest);
-  MemSetTypeFlag(&sContext.s, MEM_Null);
-
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pModule->xColumn(pCur->pVtabCursor, &sContext, pOp->p2);
-
-  /* Copy the result of the function to the P3 register. We
-  ** do this regardless of whether or not an error occured to ensure any
-  ** dynamic allocation in sContext.s (a Mem struct) is  released.
-  */
-  sqlite3VdbeChangeEncoding(&sContext.s, encoding);
-  REGISTER_TRACE(pOp->p3, pDest);
-  sqlite3VdbeMemMove(pDest, &sContext.s);
-  UPDATE_MAX_BLOBSIZE(pDest);
-
-  if( sqlite3SafetyOn(db) ){
-    goto abort_due_to_misuse;
-  }
-  if( sqlite3VdbeMemTooBig(pDest) ){
-    goto too_big;
+SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt *pStmt, int i){
+  Vdbe *p = (Vdbe*)pStmt;
+  if( p==0 || i<1 || i>p->nVar ){
+    return 0;
   }
-  break;
+  createVarMap(p);
+  return p->azVar[i-1];
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VNext P1 P2 * * *
-**
-** Advance virtual table P1 to the next row in its result set and
-** jump to instruction P2.  Or, if the virtual table has reached
-** the end of its result set, then fall through to the next instruction.
+/*
+** Given a wildcard parameter name, return the index of the variable
+** with that name.  If there is no variable with the given name,
+** return 0.
 */
-case OP_VNext: {   /* jump */
-  const sqlite3_module *pModule;
-  int res = 0;
-
-  Cursor *pCur = p->apCsr[pOp->p1];
-  assert( pCur->pVtabCursor );
-  if( pCur->nullRow ){
-    break;
+SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt *pStmt, const char *zName){
+  Vdbe *p = (Vdbe*)pStmt;
+  int i;
+  if( p==0 ){
+    return 0;
   }
-  pModule = pCur->pVtabCursor->pVtab->pModule;
-  assert( pModule->xNext );
-
-  /* Invoke the xNext() method of the module. There is no way for the
-  ** underlying implementation to return an error if one occurs during
-  ** xNext(). Instead, if an error occurs, true is returned (indicating that 
-  ** data is available) and the error code returned when xColumn or
-  ** some other method is next invoked on the save virtual table cursor.
-  */
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  p->inVtabMethod = 1;
-  rc = pModule->xNext(pCur->pVtabCursor);
-  p->inVtabMethod = 0;
-  if( rc==SQLITE_OK ){
-    res = pModule->xEof(pCur->pVtabCursor);
+  createVarMap(p); 
+  if( zName ){
+    for(i=0; i<p->nVar; i++){
+      const char *z = p->azVar[i];
+      if( z && strcmp(z,zName)==0 ){
+        return i+1;
+      }
+    }
   }
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+  return 0;
+}
 
-  if( !res ){
-    /* If there is data, jump to P2 */
-    pc = pOp->p2 - 1;
+/*
+** Transfer all bindings from the first statement over to the second.
+*/
+SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *pFromStmt, sqlite3_stmt *pToStmt){
+  Vdbe *pFrom = (Vdbe*)pFromStmt;
+  Vdbe *pTo = (Vdbe*)pToStmt;
+  int i;
+  assert( pTo->db==pFrom->db );
+  assert( pTo->nVar==pFrom->nVar );
+  sqlite3_mutex_enter(pTo->db->mutex);
+  for(i=0; i<pFrom->nVar; i++){
+    sqlite3VdbeMemMove(&pTo->aVar[i], &pFrom->aVar[i]);
   }
-  break;
+  sqlite3_mutex_leave(pTo->db->mutex);
+  return SQLITE_OK;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VRename P1 * * P4 *
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface.  Internal/core SQLite code
+** should call sqlite3TransferBindings.
 **
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** This opcode invokes the corresponding xRename method. The value
-** in register P1 is passed as the zName argument to the xRename method.
+** Is is misuse to call this routine with statements from different
+** database connections.  But as this is a deprecated interface, we
+** will not bother to check for that condition.
+**
+** If the two statements contain a different number of bindings, then
+** an SQLITE_ERROR is returned.  Nothing else can go wrong, so otherwise
+** SQLITE_OK is returned.
 */
-case OP_VRename: {
-  sqlite3_vtab *pVtab = pOp->p4.pVtab;
-  Mem *pName = &p->aMem[pOp->p1];
-  assert( pVtab->pModule->xRename );
-  REGISTER_TRACE(pOp->p1, pName);
-
-  Stringify(pName, encoding);
-
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  sqlite3VtabLock(pVtab);
-  rc = pVtab->pModule->xRename(pVtab, pName->z);
-  sqlite3VtabUnlock(db, pVtab);
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-
-  break;
+SQLITE_API int sqlite3_transfer_bindings(sqlite3_stmt *pFromStmt, sqlite3_stmt *pToStmt){
+  Vdbe *pFrom = (Vdbe*)pFromStmt;
+  Vdbe *pTo = (Vdbe*)pToStmt;
+  if( pFrom->nVar!=pTo->nVar ){
+    return SQLITE_ERROR;
+  }
+  return sqlite3TransferBindings(pFromStmt, pToStmt);
 }
 #endif
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VUpdate P1 P2 P3 P4 *
-**
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** This opcode invokes the corresponding xUpdate method. P2 values
-** are contiguous memory cells starting at P3 to pass to the xUpdate 
-** invocation. The value in register (P3+P2-1) corresponds to the 
-** p2th element of the argv array passed to xUpdate.
-**
-** The xUpdate method will do a DELETE or an INSERT or both.
-** The argv[0] element (which corresponds to memory cell P3)
-** is the rowid of a row to delete.  If argv[0] is NULL then no 
-** deletion occurs.  The argv[1] element is the rowid of the new 
-** row.  This can be NULL to have the virtual table select the new 
-** rowid for itself.  The subsequent elements in the array are 
-** the values of columns in the new row.
-**
-** If P2==1 then no insert is performed.  argv[0] is the rowid of
-** a row to delete.
-**
-** P1 is a boolean flag. If it is set to true and the xUpdate call
-** is successful, then the value returned by sqlite3_last_insert_rowid() 
-** is set to the value of the rowid for the row just inserted.
+/*
+** Return the sqlite3* database handle to which the prepared statement given
+** in the argument belongs.  This is the same database handle that was
+** the first argument to the sqlite3_prepare() that was used to create
+** the statement in the first place.
 */
-case OP_VUpdate: {
-  sqlite3_vtab *pVtab = pOp->p4.pVtab;
-  sqlite3_module *pModule = (sqlite3_module *)pVtab->pModule;
-  int nArg = pOp->p2;
-  assert( pOp->p4type==P4_VTAB );
-  if( pModule->xUpdate==0 ){
-    sqlite3SetString(&p->zErrMsg, "read-only table", 0);
-    rc = SQLITE_ERROR;
+SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt *pStmt){
+  return pStmt ? ((Vdbe*)pStmt)->db : 0;
+}
+
+/*
+** Return a pointer to the next prepared statement after pStmt associated
+** with database connection pDb.  If pStmt is NULL, return the first
+** prepared statement for the database connection.  Return NULL if there
+** are no more.
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){
+  sqlite3_stmt *pNext;
+  sqlite3_mutex_enter(pDb->mutex);
+  if( pStmt==0 ){
+    pNext = (sqlite3_stmt*)pDb->pVdbe;
   }else{
-    int i;
-    sqlite_int64 rowid;
-    Mem **apArg = p->apArg;
-    Mem *pX = &p->aMem[pOp->p3];
-    for(i=0; i<nArg; i++){
-      storeTypeInfo(pX, 0);
-      apArg[i] = pX;
-      pX++;
-    }
-    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-    sqlite3VtabLock(pVtab);
-    rc = pModule->xUpdate(pVtab, nArg, apArg, &rowid);
-    sqlite3VtabUnlock(db, pVtab);
-    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-    if( pOp->p1 && rc==SQLITE_OK ){
-      assert( nArg>1 && apArg[0] && (apArg[0]->flags&MEM_Null) );
-      db->lastRowid = rowid;
-    }
-    p->nChange++;
+    pNext = (sqlite3_stmt*)((Vdbe*)pStmt)->pNext;
   }
-  break;
+  sqlite3_mutex_leave(pDb->mutex);
+  return pNext;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_TRACE
-/* Opcode: Trace * * * P4 *
-**
-** If tracing is enabled (by the sqlite3_trace()) interface, then
-** the UTF-8 string contained in P4 is emitted on the trace callback.
+/*
+** Return the value of a status counter for a prepared statement
 */
-case OP_Trace: {
-  if( pOp->p4.z ){
-    if( db->xTrace ){
-      db->xTrace(db->pTraceArg, pOp->p4.z);
-    }
-#ifdef SQLITE_DEBUG
-    if( (db->flags & SQLITE_SqlTrace)!=0 ){
-      sqlite3DebugPrintf("SQL-trace: %s\n", pOp->p4.z);
-    }
-#endif /* SQLITE_DEBUG */
-  }
-  break;
-}
-#endif
-
-
-/* Opcode: Noop * * * * *
-**
-** Do nothing.  This instruction is often useful as a jump
-** destination.
-*/
-/*
-** The magic Explain opcode are only inserted when explain==2 (which
-** is to say when the EXPLAIN QUERY PLAN syntax is used.)
-** This opcode records information from the optimizer.  It is the
-** the same as a no-op.  This opcodesnever appears in a real VM program.
-*/
-default: {          /* This is really OP_Noop and OP_Explain */
-  break;
-}
-
-/*****************************************************************************
-** The cases of the switch statement above this line should all be indented
-** by 6 spaces.  But the left-most 6 spaces have been removed to improve the
-** readability.  From this point on down, the normal indentation rules are
-** restored.
-*****************************************************************************/
-    }
-
-#ifdef VDBE_PROFILE
-    {
-      long long elapse = hwtime() - start;
-      pOp->cycles += elapse;
-      pOp->cnt++;
-#if 0
-        fprintf(stdout, "%10lld ", elapse);
-        sqlite3VdbePrintOp(stdout, origPc, &p->aOp[origPc]);
-#endif
-    }
-#endif
-
-    /* The following code adds nothing to the actual functionality
-    ** of the program.  It is only here for testing and debugging.
-    ** On the other hand, it does burn CPU cycles every time through
-    ** the evaluator loop.  So we can leave it out when NDEBUG is defined.
-    */
-#ifndef NDEBUG
-    assert( pc>=-1 && pc<p->nOp );
-
-#ifdef SQLITE_DEBUG
-    if( p->trace ){
-      if( rc!=0 ) fprintf(p->trace,"rc=%d\n",rc);
-      if( opProperty & OPFLG_OUT2_PRERELEASE ){
-        registerTrace(p->trace, pOp->p2, pOut);
-      }
-      if( opProperty & OPFLG_OUT3 ){
-        registerTrace(p->trace, pOp->p3, pOut);
-      }
-    }
-#endif  /* SQLITE_DEBUG */
-#endif  /* NDEBUG */
-  }  /* The end of the for(;;) loop the loops through opcodes */
-
-  /* If we reach this point, it means that execution is finished with
-  ** an error of some kind.
-  */
-vdbe_error_halt:
-  assert( rc );
-  p->rc = rc;
-  rc = SQLITE_ERROR;
-  sqlite3VdbeHalt(p);
-
-  /* This is the only way out of this procedure.  We have to
-  ** release the mutexes on btrees that were acquired at the
-  ** top. */
-vdbe_return:
-  sqlite3BtreeMutexArrayLeave(&p->aMutex);
-  return rc;
-
-  /* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
-  ** is encountered.
-  */
-too_big:
-  sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
-  rc = SQLITE_TOOBIG;
-  goto vdbe_error_halt;
-
-  /* Jump to here if a malloc() fails.
-  */
-no_mem:
-  db->mallocFailed = 1;
-  sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
-  rc = SQLITE_NOMEM;
-  goto vdbe_error_halt;
-
-  /* Jump to here for an SQLITE_MISUSE error.
-  */
-abort_due_to_misuse:
-  rc = SQLITE_MISUSE;
-  /* Fall thru into abort_due_to_error */
-
-  /* Jump to here for any other kind of fatal error.  The "rc" variable
-  ** should hold the error number.
-  */
-abort_due_to_error:
-  assert( p->zErrMsg==0 );
-  if( db->mallocFailed ) rc = SQLITE_NOMEM;
-  sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
-  goto vdbe_error_halt;
-
-  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
-  ** flag.
-  */
-abort_due_to_interrupt:
-  assert( db->u1.isInterrupted );
-  rc = SQLITE_INTERRUPT;
-  p->rc = rc;
-  sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
-  goto vdbe_error_halt;
+SQLITE_API int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
+  Vdbe *pVdbe = (Vdbe*)pStmt;
+  int v = pVdbe->aCounter[op-1];
+  if( resetFlag ) pVdbe->aCounter[op-1] = 0;
+  return v;
 }
 
-/************** End of vdbe.c ************************************************/
-/************** Begin file vdbeblob.c ****************************************/
+/************** End of vdbeapi.c *********************************************/
+/************** Begin file vdbe.c ********************************************/
 /*
-** 2007 May 1
+** 2001 September 15
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -46979,587 +51400,469 @@ abort_due_to_interrupt:
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
+** The code in this file implements execution method of the 
+** Virtual Database Engine (VDBE).  A separate file ("vdbeaux.c")
+** handles housekeeping details such as creating and deleting
+** VDBE instances.  This file is solely interested in executing
+** the VDBE program.
 **
-** This file contains code used to implement incremental BLOB I/O.
+** In the external interface, an "sqlite3_stmt*" is an opaque pointer
+** to a VDBE.
+**
+** The SQL parser generates a program which is then executed by
+** the VDBE to do the work of the SQL statement.  VDBE programs are 
+** similar in form to assembly language.  The program consists of
+** a linear sequence of operations.  Each operation has an opcode 
+** and 5 operands.  Operands P1, P2, and P3 are integers.  Operand P4 
+** is a null-terminated string.  Operand P5 is an unsigned character.
+** Few opcodes use all 5 operands.
+**
+** Computation results are stored on a set of registers numbered beginning
+** with 1 and going up to Vdbe.nMem.  Each register can store
+** either an integer, a null-terminated string, a floating point
+** number, or the SQL "NULL" value.  An implicit conversion from one
+** type to the other occurs as necessary.
+** 
+** Most of the code in this file is taken up by the sqlite3VdbeExec()
+** function which does the work of interpreting a VDBE program.
+** But other routines are also provided to help in building up
+** a program instruction by instruction.
+**
+** Various scripts scan this source file in order to generate HTML
+** documentation, headers files, or other derived files.  The formatting
+** of the code in this file is, therefore, important.  See other comments
+** in this file for details.  If in doubt, do not deviate from existing
+** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbeblob.c,v 1.22 2008/04/24 09:49:55 danielk1977 Exp $
+** $Id: vdbe.c,v 1.874 2009/07/24 17:58:53 danielk1977 Exp $
 */
 
-
-#ifndef SQLITE_OMIT_INCRBLOB
-
 /*
-** Valid sqlite3_blob* handles point to Incrblob structures.
+** The following global variable is incremented every time a cursor
+** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
+** procedures use this information to make sure that indices are
+** working correctly.  This variable has no function other than to
+** help verify the correct operation of the library.
 */
-typedef struct Incrblob Incrblob;
-struct Incrblob {
-  int flags;              /* Copy of "flags" passed to sqlite3_blob_open() */
-  int nByte;              /* Size of open blob, in bytes */
-  int iOffset;            /* Byte offset of blob in cursor data */
-  BtCursor *pCsr;         /* Cursor pointing at blob row */
-  sqlite3_stmt *pStmt;    /* Statement holding cursor open */
-  sqlite3 *db;            /* The associated database */
-};
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_search_count = 0;
+#endif
 
 /*
-** Open a blob handle.
+** When this global variable is positive, it gets decremented once before
+** each instruction in the VDBE.  When reaches zero, the u1.isInterrupted
+** field of the sqlite3 structure is set in order to simulate and interrupt.
+**
+** This facility is used for testing purposes only.  It does not function
+** in an ordinary build.
 */
-SQLITE_API int sqlite3_blob_open(
-  sqlite3* db,            /* The database connection */
-  const char *zDb,        /* The attached database containing the blob */
-  const char *zTable,     /* The table containing the blob */
-  const char *zColumn,    /* The column containing the blob */
-  sqlite_int64 iRow,      /* The row containing the glob */
-  int flags,              /* True -> read/write access, false -> read-only */
-  sqlite3_blob **ppBlob   /* Handle for accessing the blob returned here */
-){
-  int nAttempt = 0;
-  int iCol;               /* Index of zColumn in row-record */
-
-  /* This VDBE program seeks a btree cursor to the identified 
-  ** db/table/row entry. The reason for using a vdbe program instead
-  ** of writing code to use the b-tree layer directly is that the
-  ** vdbe program will take advantage of the various transaction,
-  ** locking and error handling infrastructure built into the vdbe.
-  **
-  ** After seeking the cursor, the vdbe executes an OP_ResultRow.
-  ** Code external to the Vdbe then "borrows" the b-tree cursor and
-  ** uses it to implement the blob_read(), blob_write() and 
-  ** blob_bytes() functions.
-  **
-  ** The sqlite3_blob_close() function finalizes the vdbe program,
-  ** which closes the b-tree cursor and (possibly) commits the 
-  ** transaction.
-  */
-  static const VdbeOpList openBlob[] = {
-    {OP_Transaction, 0, 0, 0},     /* 0: Start a transaction */
-    {OP_VerifyCookie, 0, 0, 0},    /* 1: Check the schema cookie */
-
-    /* One of the following two instructions is replaced by an
-    ** OP_Noop before exection.
-    */
-    {OP_SetNumColumns, 0, 0, 0},   /* 2: Num cols for cursor */
-    {OP_OpenRead, 0, 0, 0},        /* 3: Open cursor 0 for reading */
-    {OP_SetNumColumns, 0, 0, 0},   /* 4: Num cols for cursor */
-    {OP_OpenWrite, 0, 0, 0},       /* 5: Open cursor 0 for read/write */
-
-    {OP_Variable, 1, 1, 0},        /* 6: Push the rowid to the stack */
-    {OP_NotExists, 0, 10, 1},      /* 7: Seek the cursor */
-    {OP_Column, 0, 0, 1},          /* 8  */
-    {OP_ResultRow, 1, 0, 0},       /* 9  */
-    {OP_Close, 0, 0, 0},           /* 10  */
-    {OP_Halt, 0, 0, 0},            /* 11 */
-  };
-
-  Vdbe *v = 0;
-  int rc = SQLITE_OK;
-  char zErr[128];
-
-  zErr[0] = 0;
-  sqlite3_mutex_enter(db->mutex);
-  do {
-    Parse sParse;
-    Table *pTab;
-
-    memset(&sParse, 0, sizeof(Parse));
-    sParse.db = db;
-
-    rc = sqlite3SafetyOn(db);
-    if( rc!=SQLITE_OK ){
-      sqlite3_mutex_leave(db->mutex);
-      return rc;
-    }
-
-    sqlite3BtreeEnterAll(db);
-    pTab = sqlite3LocateTable(&sParse, 0, zTable, zDb);
-    if( pTab && IsVirtual(pTab) ){
-      pTab = 0;
-      sqlite3ErrorMsg(&sParse, "cannot open virtual table: %s", zTable);
-    }
-#ifndef SQLITE_OMIT_VIEW
-    if( pTab && pTab->pSelect ){
-      pTab = 0;
-      sqlite3ErrorMsg(&sParse, "cannot open view: %s", zTable);
-    }
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_interrupt_count = 0;
 #endif
-    if( !pTab ){
-      if( sParse.zErrMsg ){
-        sqlite3_snprintf(sizeof(zErr), zErr, "%s", sParse.zErrMsg);
-      }
-      sqlite3_free(sParse.zErrMsg);
-      rc = SQLITE_ERROR;
-      (void)sqlite3SafetyOff(db);
-      sqlite3BtreeLeaveAll(db);
-      goto blob_open_out;
-    }
-
-    /* Now search pTab for the exact column. */
-    for(iCol=0; iCol < pTab->nCol; iCol++) {
-      if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
-        break;
-      }
-    }
-    if( iCol==pTab->nCol ){
-      sqlite3_snprintf(sizeof(zErr), zErr, "no such column: \"%s\"", zColumn);
-      rc = SQLITE_ERROR;
-      (void)sqlite3SafetyOff(db);
-      sqlite3BtreeLeaveAll(db);
-      goto blob_open_out;
-    }
-
-    /* If the value is being opened for writing, check that the
-    ** column is not indexed. It is against the rules to open an
-    ** indexed column for writing.
-    */
-    if( flags ){
-      Index *pIdx;
-      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-        int j;
-        for(j=0; j<pIdx->nColumn; j++){
-          if( pIdx->aiColumn[j]==iCol ){
-            sqlite3_snprintf(sizeof(zErr), zErr,
-                             "cannot open indexed column for writing");
-            rc = SQLITE_ERROR;
-            (void)sqlite3SafetyOff(db);
-            sqlite3BtreeLeaveAll(db);
-            goto blob_open_out;
-          }
-        }
-      }
-    }
-
-    v = sqlite3VdbeCreate(db);
-    if( v ){
-      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-      sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);
-
-      /* Configure the OP_Transaction */
-      sqlite3VdbeChangeP1(v, 0, iDb);
-      sqlite3VdbeChangeP2(v, 0, (flags ? 1 : 0));
-
-      /* Configure the OP_VerifyCookie */
-      sqlite3VdbeChangeP1(v, 1, iDb);
-      sqlite3VdbeChangeP2(v, 1, pTab->pSchema->schema_cookie);
-
-      /* Make sure a mutex is held on the table to be accessed */
-      sqlite3VdbeUsesBtree(v, iDb); 
-
-      /* Remove either the OP_OpenWrite or OpenRead. Set the P2 
-      ** parameter of the other to pTab->tnum. 
-      */
-      sqlite3VdbeChangeToNoop(v, (flags ? 3 : 5), 1);
-      sqlite3VdbeChangeP2(v, (flags ? 5 : 3), pTab->tnum);
-      sqlite3VdbeChangeP3(v, (flags ? 5 : 3), iDb);
-
-      /* Configure the OP_SetNumColumns. Configure the cursor to
-      ** think that the table has one more column than it really
-      ** does. An OP_Column to retrieve this imaginary column will
-      ** always return an SQL NULL. This is useful because it means
-      ** we can invoke OP_Column to fill in the vdbe cursors type 
-      ** and offset cache without causing any IO.
-      */
-      sqlite3VdbeChangeP2(v, flags ? 4 : 2, pTab->nCol+1);
-      if( !db->mallocFailed ){
-        sqlite3VdbeMakeReady(v, 1, 1, 1, 0);
-      }
-    }
-   
-    sqlite3BtreeLeaveAll(db);
-    rc = sqlite3SafetyOff(db);
-    if( rc!=SQLITE_OK || db->mallocFailed ){
-      goto blob_open_out;
-    }
-
-    sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
-    rc = sqlite3_step((sqlite3_stmt *)v);
-    if( rc!=SQLITE_ROW ){
-      nAttempt++;
-      rc = sqlite3_finalize((sqlite3_stmt *)v);
-      sqlite3_snprintf(sizeof(zErr), zErr, sqlite3_errmsg(db));
-      v = 0;
-    }
-  } while( nAttempt<5 && rc==SQLITE_SCHEMA );
-
-  if( rc==SQLITE_ROW ){
-    /* The row-record has been opened successfully. Check that the
-    ** column in question contains text or a blob. If it contains
-    ** text, it is up to the caller to get the encoding right.
-    */
-    Incrblob *pBlob;
-    u32 type = v->apCsr[0]->aType[iCol];
-
-    if( type<12 ){
-      sqlite3_snprintf(sizeof(zErr), zErr, "cannot open value of type %s",
-          type==0?"null": type==7?"real": "integer"
-      );
-      rc = SQLITE_ERROR;
-      goto blob_open_out;
-    }
-    pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
-    if( db->mallocFailed ){
-      sqlite3_free(pBlob);
-      goto blob_open_out;
-    }
-    pBlob->flags = flags;
-    pBlob->pCsr =  v->apCsr[0]->pCursor;
-    sqlite3BtreeEnterCursor(pBlob->pCsr);
-    sqlite3BtreeCacheOverflow(pBlob->pCsr);
-    sqlite3BtreeLeaveCursor(pBlob->pCsr);
-    pBlob->pStmt = (sqlite3_stmt *)v;
-    pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
-    pBlob->nByte = sqlite3VdbeSerialTypeLen(type);
-    pBlob->db = db;
-    *ppBlob = (sqlite3_blob *)pBlob;
-    rc = SQLITE_OK;
-  }else if( rc==SQLITE_OK ){
-    sqlite3_snprintf(sizeof(zErr), zErr, "no such rowid: %lld", iRow);
-    rc = SQLITE_ERROR;
-  }
-
-blob_open_out:
-  zErr[sizeof(zErr)-1] = '\0';
-  if( rc!=SQLITE_OK || db->mallocFailed ){
-    sqlite3_finalize((sqlite3_stmt *)v);
-  }
-  sqlite3Error(db, rc, (rc==SQLITE_OK?0:zErr));
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
 
 /*
-** Close a blob handle that was previously created using
-** sqlite3_blob_open().
+** The next global variable is incremented each type the OP_Sort opcode
+** is executed.  The test procedures use this information to make sure that
+** sorting is occurring or not occurring at appropriate times.   This variable
+** has no function other than to help verify the correct operation of the
+** library.
 */
-SQLITE_API int sqlite3_blob_close(sqlite3_blob *pBlob){
-  Incrblob *p = (Incrblob *)pBlob;
-  int rc;
-
-  rc = sqlite3_finalize(p->pStmt);
-  sqlite3_free(p);
-  return rc;
-}
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_sort_count = 0;
+#endif
 
 /*
-** Perform a read or write operation on a blob
+** The next global variable records the size of the largest MEM_Blob
+** or MEM_Str that has been used by a VDBE opcode.  The test procedures
+** use this information to make sure that the zero-blob functionality
+** is working correctly.   This variable has no function other than to
+** help verify the correct operation of the library.
 */
-static int blobReadWrite(
-  sqlite3_blob *pBlob, 
-  void *z, 
-  int n, 
-  int iOffset, 
-  int (*xCall)(BtCursor*, u32, u32, void*)
-){
-  int rc;
-  Incrblob *p = (Incrblob *)pBlob;
-  Vdbe *v;
-  sqlite3 *db = p->db;  
-
-  /* Request is out of range. Return a transient error. */
-  if( (iOffset+n)>p->nByte ){
-    return SQLITE_ERROR;
-  }
-  sqlite3_mutex_enter(db->mutex);
-
-  /* If there is no statement handle, then the blob-handle has
-  ** already been invalidated. Return SQLITE_ABORT in this case.
-  */
-  v = (Vdbe*)p->pStmt;
-  if( v==0 ){
-    rc = SQLITE_ABORT;
-  }else{
-    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
-    ** returned, clean-up the statement handle.
-    */
-    assert( db == v->db );
-    sqlite3BtreeEnterCursor(p->pCsr);
-    rc = xCall(p->pCsr, iOffset+p->iOffset, n, z);
-    sqlite3BtreeLeaveCursor(p->pCsr);
-    if( rc==SQLITE_ABORT ){
-      sqlite3VdbeFinalize(v);
-      p->pStmt = 0;
-    }else{
-      db->errCode = rc;
-      v->rc = rc;
-    }
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_max_blobsize = 0;
+static void updateMaxBlobsize(Mem *p){
+  if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
+    sqlite3_max_blobsize = p->n;
   }
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
 }
+#endif
 
 /*
-** Read data from a blob handle.
+** The next global variable is incremented each type the OP_Found opcode
+** is executed. This is used to test whether or not the foreign key
+** operation implemented using OP_FkIsZero is working. This variable
+** has no function other than to help verify the correct operation of the
+** library.
 */
-SQLITE_API int sqlite3_blob_read(sqlite3_blob *pBlob, void *z, int n, int iOffset){
-  return blobReadWrite(pBlob, z, n, iOffset, sqlite3BtreeData);
-}
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_found_count = 0;
+#endif
 
 /*
-** Write data to a blob handle.
+** Test a register to see if it exceeds the current maximum blob size.
+** If it does, record the new maximum blob size.
 */
-SQLITE_API int sqlite3_blob_write(sqlite3_blob *pBlob, const void *z, int n, int iOffset){
-  return blobReadWrite(pBlob, (void *)z, n, iOffset, sqlite3BtreePutData);
-}
+#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
+# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
+#else
+# define UPDATE_MAX_BLOBSIZE(P)
+#endif
 
 /*
-** Query a blob handle for the size of the data.
-**
-** The Incrblob.nByte field is fixed for the lifetime of the Incrblob
-** so no mutex is required for access.
+** Convert the given register into a string if it isn't one
+** already. Return non-zero if a malloc() fails.
 */
-SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *pBlob){
-  Incrblob *p = (Incrblob *)pBlob;
-  return p->nByte;
-}
-
-#endif /* #ifndef SQLITE_OMIT_INCRBLOB */
+#define Stringify(P, enc) \
+   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
+     { goto no_mem; }
 
-/************** End of vdbeblob.c ********************************************/
-/************** Begin file journal.c *****************************************/
 /*
-** 2007 August 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
+** An ephemeral string value (signified by the MEM_Ephem flag) contains
+** a pointer to a dynamically allocated string where some other entity
+** is responsible for deallocating that string.  Because the register
+** does not control the string, it might be deleted without the register
+** knowing it.
 **
-** @(#) $Id: journal.c,v 1.8 2008/05/01 18:01:47 drh Exp $
+** This routine converts an ephemeral string into a dynamically allocated
+** string that the register itself controls.  In other words, it
+** converts an MEM_Ephem string into an MEM_Dyn string.
 */
-
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+#define Deephemeralize(P) \
+   if( ((P)->flags&MEM_Ephem)!=0 \
+       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
 
 /*
-** This file implements a special kind of sqlite3_file object used
-** by SQLite to create journal files if the atomic-write optimization
-** is enabled.
-**
-** The distinctive characteristic of this sqlite3_file is that the
-** actual on disk file is created lazily. When the file is created,
-** the caller specifies a buffer size for an in-memory buffer to
-** be used to service read() and write() requests. The actual file
-** on disk is not created or populated until either:
-**
-**   1) The in-memory representation grows too large for the allocated 
-**      buffer, or
-**   2) The xSync() method is called.
+** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
+** P if required.
 */
-
-
+#define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
 
 /*
-** A JournalFile object is a subclass of sqlite3_file used by
-** as an open file handle for journal files.
+** Argument pMem points at a register that will be passed to a
+** user-defined function or returned to the user as the result of a query.
+** The second argument, 'db_enc' is the text encoding used by the vdbe for
+** register variables.  This routine sets the pMem->enc and pMem->type
+** variables used by the sqlite3_value_*() routines.
 */
-struct JournalFile {
-  sqlite3_io_methods *pMethod;    /* I/O methods on journal files */
-  int nBuf;                       /* Size of zBuf[] in bytes */
-  char *zBuf;                     /* Space to buffer journal writes */
-  int iSize;                      /* Amount of zBuf[] currently used */
-  int flags;                      /* xOpen flags */
-  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
-  sqlite3_file *pReal;            /* The "real" underlying file descriptor */
-  const char *zJournal;           /* Name of the journal file */
-};
-typedef struct JournalFile JournalFile;
+#define storeTypeInfo(A,B) _storeTypeInfo(A)
+static void _storeTypeInfo(Mem *pMem){
+  int flags = pMem->flags;
+  if( flags & MEM_Null ){
+    pMem->type = SQLITE_NULL;
+  }
+  else if( flags & MEM_Int ){
+    pMem->type = SQLITE_INTEGER;
+  }
+  else if( flags & MEM_Real ){
+    pMem->type = SQLITE_FLOAT;
+  }
+  else if( flags & MEM_Str ){
+    pMem->type = SQLITE_TEXT;
+  }else{
+    pMem->type = SQLITE_BLOB;
+  }
+}
 
 /*
-** If it does not already exists, create and populate the on-disk file 
-** for JournalFile p.
+** Properties of opcodes.  The OPFLG_INITIALIZER macro is
+** created by mkopcodeh.awk during compilation.  Data is obtained
+** from the comments following the "case OP_xxxx:" statements in
+** this file.  
 */
-static int createFile(JournalFile *p){
-  int rc = SQLITE_OK;
-  if( !p->pReal ){
-    sqlite3_file *pReal = (sqlite3_file *)&p[1];
-    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
-    if( rc==SQLITE_OK ){
-      p->pReal = pReal;
-      if( p->iSize>0 ){
-        assert(p->iSize<=p->nBuf);
-        rc = sqlite3OsWrite(p->pReal, p->zBuf, p->iSize, 0);
-      }
-    }
-  }
-  return rc;
-}
+static const unsigned char opcodeProperty[] = OPFLG_INITIALIZER;
 
 /*
-** Close the file.
+** Return true if an opcode has any of the OPFLG_xxx properties
+** specified by mask.
 */
-static int jrnlClose(sqlite3_file *pJfd){
-  JournalFile *p = (JournalFile *)pJfd;
-  if( p->pReal ){
-    sqlite3OsClose(p->pReal);
-  }
-  sqlite3_free(p->zBuf);
-  return SQLITE_OK;
+SQLITE_PRIVATE int sqlite3VdbeOpcodeHasProperty(int opcode, int mask){
+  assert( opcode>0 && opcode<(int)sizeof(opcodeProperty) );
+  return (opcodeProperty[opcode]&mask)!=0;
 }
 
 /*
-** Read data from the file.
+** Allocate VdbeCursor number iCur.  Return a pointer to it.  Return NULL
+** if we run out of memory.
 */
-static int jrnlRead(
-  sqlite3_file *pJfd,    /* The journal file from which to read */
-  void *zBuf,            /* Put the results here */
-  int iAmt,              /* Number of bytes to read */
-  sqlite_int64 iOfst     /* Begin reading at this offset */
+static VdbeCursor *allocateCursor(
+  Vdbe *p,              /* The virtual machine */
+  int iCur,             /* Index of the new VdbeCursor */
+  int nField,           /* Number of fields in the table or index */
+  int iDb,              /* When database the cursor belongs to, or -1 */
+  int isBtreeCursor     /* True for B-Tree.  False for pseudo-table or vtab */
 ){
-  int rc = SQLITE_OK;
-  JournalFile *p = (JournalFile *)pJfd;
-  if( p->pReal ){
-    rc = sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst);
-  }else{
-    assert( iAmt+iOfst<=p->iSize );
-    memcpy(zBuf, &p->zBuf[iOfst], iAmt);
+  /* Find the memory cell that will be used to store the blob of memory
+  ** required for this VdbeCursor structure. It is convenient to use a 
+  ** vdbe memory cell to manage the memory allocation required for a
+  ** VdbeCursor structure for the following reasons:
+  **
+  **   * Sometimes cursor numbers are used for a couple of different
+  **     purposes in a vdbe program. The different uses might require
+  **     different sized allocations. Memory cells provide growable
+  **     allocations.
+  **
+  **   * When using ENABLE_MEMORY_MANAGEMENT, memory cell buffers can
+  **     be freed lazily via the sqlite3_release_memory() API. This
+  **     minimizes the number of malloc calls made by the system.
+  **
+  ** Memory cells for cursors are allocated at the top of the address
+  ** space. Memory cell (p->nMem) corresponds to cursor 0. Space for
+  ** cursor 1 is managed by memory cell (p->nMem-1), etc.
+  */
+  Mem *pMem = &p->aMem[p->nMem-iCur];
+
+  int nByte;
+  VdbeCursor *pCx = 0;
+  nByte = 
+      sizeof(VdbeCursor) + 
+      (isBtreeCursor?sqlite3BtreeCursorSize():0) + 
+      2*nField*sizeof(u32);
+
+  assert( iCur<p->nCursor );
+  if( p->apCsr[iCur] ){
+    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
+    p->apCsr[iCur] = 0;
   }
-  return rc;
+  if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
+    p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->z;
+    memset(pMem->z, 0, nByte);
+    pCx->iDb = iDb;
+    pCx->nField = nField;
+    if( nField ){
+      pCx->aType = (u32 *)&pMem->z[sizeof(VdbeCursor)];
+    }
+    if( isBtreeCursor ){
+      pCx->pCursor = (BtCursor*)
+          &pMem->z[sizeof(VdbeCursor)+2*nField*sizeof(u32)];
+    }
+  }
+  return pCx;
 }
 
 /*
-** Write data to the file.
+** Try to convert a value into a numeric representation if we can
+** do so without loss of information.  In other words, if the string
+** looks like a number, convert it into a number.  If it does not
+** look like a number, leave it alone.
 */
-static int jrnlWrite(
-  sqlite3_file *pJfd,    /* The journal file into which to write */
-  const void *zBuf,      /* Take data to be written from here */
-  int iAmt,              /* Number of bytes to write */
-  sqlite_int64 iOfst     /* Begin writing at this offset into the file */
-){
-  int rc = SQLITE_OK;
-  JournalFile *p = (JournalFile *)pJfd;
-  if( !p->pReal && (iOfst+iAmt)>p->nBuf ){
-    rc = createFile(p);
-  }
-  if( rc==SQLITE_OK ){
-    if( p->pReal ){
-      rc = sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
-    }else{
-      memcpy(&p->zBuf[iOfst], zBuf, iAmt);
-      if( p->iSize<(iOfst+iAmt) ){
-        p->iSize = (iOfst+iAmt);
+static void applyNumericAffinity(Mem *pRec){
+  if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
+    int realnum;
+    sqlite3VdbeMemNulTerminate(pRec);
+    if( (pRec->flags&MEM_Str)
+         && sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
+      i64 value;
+      sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
+      if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
+        pRec->u.i = value;
+        MemSetTypeFlag(pRec, MEM_Int);
+      }else{
+        sqlite3VdbeMemRealify(pRec);
       }
     }
   }
-  return rc;
 }
 
 /*
-** Truncate the file.
+** Processing is determine by the affinity parameter:
+**
+** SQLITE_AFF_INTEGER:
+** SQLITE_AFF_REAL:
+** SQLITE_AFF_NUMERIC:
+**    Try to convert pRec to an integer representation or a 
+**    floating-point representation if an integer representation
+**    is not possible.  Note that the integer representation is
+**    always preferred, even if the affinity is REAL, because
+**    an integer representation is more space efficient on disk.
+**
+** SQLITE_AFF_TEXT:
+**    Convert pRec to a text representation.
+**
+** SQLITE_AFF_NONE:
+**    No-op.  pRec is unchanged.
 */
-static int jrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
-  int rc = SQLITE_OK;
-  JournalFile *p = (JournalFile *)pJfd;
-  if( p->pReal ){
-    rc = sqlite3OsTruncate(p->pReal, size);
-  }else if( size<p->iSize ){
-    p->iSize = size;
+static void applyAffinity(
+  Mem *pRec,          /* The value to apply affinity to */
+  char affinity,      /* The affinity to be applied */
+  u8 enc              /* Use this text encoding */
+){
+  if( affinity==SQLITE_AFF_TEXT ){
+    /* Only attempt the conversion to TEXT if there is an integer or real
+    ** representation (blob and NULL do not get converted) but no string
+    ** representation.
+    */
+    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
+      sqlite3VdbeMemStringify(pRec, enc);
+    }
+    pRec->flags &= ~(MEM_Real|MEM_Int);
+  }else if( affinity!=SQLITE_AFF_NONE ){
+    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
+             || affinity==SQLITE_AFF_NUMERIC );
+    applyNumericAffinity(pRec);
+    if( pRec->flags & MEM_Real ){
+      sqlite3VdbeIntegerAffinity(pRec);
+    }
   }
-  return rc;
 }
 
 /*
-** Sync the file.
+** Try to convert the type of a function argument or a result column
+** into a numeric representation.  Use either INTEGER or REAL whichever
+** is appropriate.  But only do the conversion if it is possible without
+** loss of information and return the revised type of the argument.
+**
+** This is an EXPERIMENTAL api and is subject to change or removal.
 */
-static int jrnlSync(sqlite3_file *pJfd, int flags){
-  int rc;
-  JournalFile *p = (JournalFile *)pJfd;
-  if( p->pReal ){
-    rc = sqlite3OsSync(p->pReal, flags);
-  }else{
-    rc = SQLITE_OK;
-  }
-  return rc;
+SQLITE_API int sqlite3_value_numeric_type(sqlite3_value *pVal){
+  Mem *pMem = (Mem*)pVal;
+  applyNumericAffinity(pMem);
+  storeTypeInfo(pMem, 0);
+  return pMem->type;
 }
 
 /*
-** Query the size of the file in bytes.
+** Exported version of applyAffinity(). This one works on sqlite3_value*, 
+** not the internal Mem* type.
 */
-static int jrnlFileSize(sqlite3_file *pJfd, sqlite_int64 *pSize){
-  int rc = SQLITE_OK;
-  JournalFile *p = (JournalFile *)pJfd;
-  if( p->pReal ){
-    rc = sqlite3OsFileSize(p->pReal, pSize);
-  }else{
-    *pSize = (sqlite_int64) p->iSize;
-  }
-  return rc;
+SQLITE_PRIVATE void sqlite3ValueApplyAffinity(
+  sqlite3_value *pVal, 
+  u8 affinity, 
+  u8 enc
+){
+  applyAffinity((Mem *)pVal, affinity, enc);
 }
 
+#ifdef SQLITE_DEBUG
 /*
-** Table of methods for JournalFile sqlite3_file object.
+** Write a nice string representation of the contents of cell pMem
+** into buffer zBuf, length nBuf.
 */
-static struct sqlite3_io_methods JournalFileMethods = {
-  1,             /* iVersion */
-  jrnlClose,     /* xClose */
-  jrnlRead,      /* xRead */
-  jrnlWrite,     /* xWrite */
-  jrnlTruncate,  /* xTruncate */
-  jrnlSync,      /* xSync */
-  jrnlFileSize,  /* xFileSize */
-  0,             /* xLock */
-  0,             /* xUnlock */
-  0,             /* xCheckReservedLock */
-  0,             /* xFileControl */
-  0,             /* xSectorSize */
-  0              /* xDeviceCharacteristics */
-};
+SQLITE_PRIVATE void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf){
+  char *zCsr = zBuf;
+  int f = pMem->flags;
 
-/* 
-** Open a journal file.
-*/
-SQLITE_PRIVATE int sqlite3JournalOpen(
-  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
-  const char *zName,         /* Name of the journal file */
-  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
-  int flags,                 /* Opening flags */
-  int nBuf                   /* Bytes buffered before opening the file */
-){
-  JournalFile *p = (JournalFile *)pJfd;
-  memset(p, 0, sqlite3JournalSize(pVfs));
-  if( nBuf>0 ){
-    p->zBuf = sqlite3MallocZero(nBuf);
-    if( !p->zBuf ){
-      return SQLITE_NOMEM;
+  static const char *const encnames[] = {"(X)", "(8)", "(16LE)", "(16BE)"};
+
+  if( f&MEM_Blob ){
+    int i;
+    char c;
+    if( f & MEM_Dyn ){
+      c = 'z';
+      assert( (f & (MEM_Static|MEM_Ephem))==0 );
+    }else if( f & MEM_Static ){
+      c = 't';
+      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
+    }else if( f & MEM_Ephem ){
+      c = 'e';
+      assert( (f & (MEM_Static|MEM_Dyn))==0 );
+    }else{
+      c = 's';
     }
-  }else{
-    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
+
+    sqlite3_snprintf(100, zCsr, "%c", c);
+    zCsr += sqlite3Strlen30(zCsr);
+    sqlite3_snprintf(100, zCsr, "%d[", pMem->n);
+    zCsr += sqlite3Strlen30(zCsr);
+    for(i=0; i<16 && i<pMem->n; i++){
+      sqlite3_snprintf(100, zCsr, "%02X", ((int)pMem->z[i] & 0xFF));
+      zCsr += sqlite3Strlen30(zCsr);
+    }
+    for(i=0; i<16 && i<pMem->n; i++){
+      char z = pMem->z[i];
+      if( z<32 || z>126 ) *zCsr++ = '.';
+      else *zCsr++ = z;
+    }
+
+    sqlite3_snprintf(100, zCsr, "]%s", encnames[pMem->enc]);
+    zCsr += sqlite3Strlen30(zCsr);
+    if( f & MEM_Zero ){
+      sqlite3_snprintf(100, zCsr,"+%dz",pMem->u.nZero);
+      zCsr += sqlite3Strlen30(zCsr);
+    }
+    *zCsr = '\0';
+  }else if( f & MEM_Str ){
+    int j, k;
+    zBuf[0] = ' ';
+    if( f & MEM_Dyn ){
+      zBuf[1] = 'z';
+      assert( (f & (MEM_Static|MEM_Ephem))==0 );
+    }else if( f & MEM_Static ){
+      zBuf[1] = 't';
+      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
+    }else if( f & MEM_Ephem ){
+      zBuf[1] = 'e';
+      assert( (f & (MEM_Static|MEM_Dyn))==0 );
+    }else{
+      zBuf[1] = 's';
+    }
+    k = 2;
+    sqlite3_snprintf(100, &zBuf[k], "%d", pMem->n);
+    k += sqlite3Strlen30(&zBuf[k]);
+    zBuf[k++] = '[';
+    for(j=0; j<15 && j<pMem->n; j++){
+      u8 c = pMem->z[j];
+      if( c>=0x20 && c<0x7f ){
+        zBuf[k++] = c;
+      }else{
+        zBuf[k++] = '.';
+      }
+    }
+    zBuf[k++] = ']';
+    sqlite3_snprintf(100,&zBuf[k], encnames[pMem->enc]);
+    k += sqlite3Strlen30(&zBuf[k]);
+    zBuf[k++] = 0;
   }
-  p->pMethod = &JournalFileMethods;
-  p->nBuf = nBuf;
-  p->flags = flags;
-  p->zJournal = zName;
-  p->pVfs = pVfs;
-  return SQLITE_OK;
 }
+#endif
 
+#ifdef SQLITE_DEBUG
 /*
-** If the argument p points to a JournalFile structure, and the underlying
-** file has not yet been created, create it now.
+** Print the value of a register for tracing purposes:
 */
-SQLITE_PRIVATE int sqlite3JournalCreate(sqlite3_file *p){
-  if( p->pMethods!=&JournalFileMethods ){
-    return SQLITE_OK;
+static void memTracePrint(FILE *out, Mem *p){
+  if( p->flags & MEM_Null ){
+    fprintf(out, " NULL");
+  }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
+    fprintf(out, " si:%lld", p->u.i);
+  }else if( p->flags & MEM_Int ){
+    fprintf(out, " i:%lld", p->u.i);
+#ifndef SQLITE_OMIT_FLOATING_POINT
+  }else if( p->flags & MEM_Real ){
+    fprintf(out, " r:%g", p->r);
+#endif
+  }else if( p->flags & MEM_RowSet ){
+    fprintf(out, " (rowset)");
+  }else{
+    char zBuf[200];
+    sqlite3VdbeMemPrettyPrint(p, zBuf);
+    fprintf(out, " ");
+    fprintf(out, "%s", zBuf);
   }
-  return createFile((JournalFile *)p);
 }
-
-/* 
-** Return the number of bytes required to store a JournalFile that uses vfs
-** pVfs to create the underlying on-disk files.
-*/
-SQLITE_PRIVATE int sqlite3JournalSize(sqlite3_vfs *pVfs){
-  return (pVfs->szOsFile+sizeof(JournalFile));
+static void registerTrace(FILE *out, int iReg, Mem *p){
+  fprintf(out, "REG[%d] = ", iReg);
+  memTracePrint(out, p);
+  fprintf(out, "\n");
 }
 #endif
 
-/************** End of journal.c *********************************************/
-/************** Begin file expr.c ********************************************/
+#ifdef SQLITE_DEBUG
+#  define REGISTER_TRACE(R,M) if(p->trace)registerTrace(p->trace,R,M)
+#else
+#  define REGISTER_TRACE(R,M)
+#endif
+
+
+#ifdef VDBE_PROFILE
+
+/* 
+** hwtime.h contains inline assembler code for implementing 
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of vdbe.c *********************/
+/************** Begin file hwtime.h ******************************************/
 /*
-** 2001 September 15
+** 2008 May 27
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -47568,4513 +51871,6280 @@ SQLITE_PRIVATE int sqlite3JournalSize(sqlite3_vfs *pVfs){
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-*************************************************************************
-** This file contains routines used for analyzing expressions and
-** for generating VDBE code that evaluates expressions in SQLite.
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
 **
-** $Id: expr.c,v 1.371 2008/05/01 17:16:53 drh Exp $
+** $Id: hwtime.h,v 1.3 2008/08/01 14:33:15 shane Exp $
 */
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
 
 /*
-** Return the 'affinity' of the expression pExpr if any.
-**
-** If pExpr is a column, a reference to a column via an 'AS' alias,
-** or a sub-select with a column as the return value, then the 
-** affinity of that column is returned. Otherwise, 0x00 is returned,
-** indicating no affinity for the expression.
-**
-** i.e. the WHERE clause expresssions in the following statements all
-** have an affinity:
-**
-** CREATE TABLE t1(a);
-** SELECT * FROM t1 WHERE a;
-** SELECT a AS b FROM t1 WHERE b;
-** SELECT * FROM t1 WHERE (select a from t1);
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value.  This can be used for high-res
+** profiling.
 */
-SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr){
-  int op = pExpr->op;
-  if( op==TK_SELECT ){
-    return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+      (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+  #if defined(__GNUC__)
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+     unsigned int lo, hi;
+     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+     return (sqlite_uint64)hi << 32 | lo;
   }
-#ifndef SQLITE_OMIT_CAST
-  if( op==TK_CAST ){
-    return sqlite3AffinityType(&pExpr->token);
+
+  #elif defined(_MSC_VER)
+
+  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+     __asm {
+        rdtsc
+        ret       ; return value at EDX:EAX
+     }
+  }
+
+  #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long val;
+      __asm__ __volatile__ ("rdtsc" : "=A" (val));
+      return val;
+  }
+ 
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+  __inline__ sqlite_uint64 sqlite3Hwtime(void){
+      unsigned long long retval;
+      unsigned long junk;
+      __asm__ __volatile__ ("\n\
+          1:      mftbu   %1\n\
+                  mftb    %L0\n\
+                  mftbu   %0\n\
+                  cmpw    %0,%1\n\
+                  bne     1b"
+                  : "=r" (retval), "=r" (junk));
+      return retval;
   }
+
+#else
+
+  #error Need implementation of sqlite3Hwtime() for your platform.
+
+  /*
+  ** To compile without implementing sqlite3Hwtime() for your platform,
+  ** you can remove the above #error and use the following
+  ** stub function.  You will lose timing support for many
+  ** of the debugging and testing utilities, but it should at
+  ** least compile and run.
+  */
+SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in vdbe.c ***********************/
+
 #endif
-  return pExpr->affinity;
-}
 
 /*
-** Set the collating sequence for expression pExpr to be the collating
-** sequence named by pToken.   Return a pointer to the revised expression.
-** The collating sequence is marked as "explicit" using the EP_ExpCollate
-** flag.  An explicit collating sequence will override implicit
-** collating sequences.
+** The CHECK_FOR_INTERRUPT macro defined here looks to see if the
+** sqlite3_interrupt() routine has been called.  If it has been, then
+** processing of the VDBE program is interrupted.
+**
+** This macro added to every instruction that does a jump in order to
+** implement a loop.  This test used to be on every single instruction,
+** but that meant we more testing that we needed.  By only testing the
+** flag on jump instructions, we get a (small) speed improvement.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pName){
-  char *zColl = 0;            /* Dequoted name of collation sequence */
-  CollSeq *pColl;
-  zColl = sqlite3NameFromToken(pParse->db, pName);
-  if( pExpr && zColl ){
-    pColl = sqlite3LocateCollSeq(pParse, zColl, -1);
-    if( pColl ){
-      pExpr->pColl = pColl;
-      pExpr->flags |= EP_ExpCollate;
-    }
-  }
-  sqlite3_free(zColl);
-  return pExpr;
+#define CHECK_FOR_INTERRUPT \
+   if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
+
+#ifdef SQLITE_DEBUG
+static int fileExists(sqlite3 *db, const char *zFile){
+  int res = 0;
+  int rc = SQLITE_OK;
+#ifdef SQLITE_TEST
+  /* If we are currently testing IO errors, then do not call OsAccess() to
+  ** test for the presence of zFile. This is because any IO error that
+  ** occurs here will not be reported, causing the test to fail.
+  */
+  extern int sqlite3_io_error_pending;
+  if( sqlite3_io_error_pending<=0 )
+#endif
+    rc = sqlite3OsAccess(db->pVfs, zFile, SQLITE_ACCESS_EXISTS, &res);
+  return (res && rc==SQLITE_OK);
 }
+#endif
 
+#ifndef NDEBUG
 /*
-** Return the default collation sequence for the expression pExpr. If
-** there is no default collation type, return 0.
+** This function is only called from within an assert() expression. It
+** checks that the sqlite3.nTransaction variable is correctly set to
+** the number of non-transaction savepoints currently in the 
+** linked list starting at sqlite3.pSavepoint.
+** 
+** Usage:
+**
+**     assert( checkSavepointCount(db) );
 */
-SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
-  CollSeq *pColl = 0;
-  if( pExpr ){
-    int op;
-    pColl = pExpr->pColl;
-    op = pExpr->op;
-    if( (op==TK_CAST || op==TK_UPLUS) && !pColl ){
-      return sqlite3ExprCollSeq(pParse, pExpr->pLeft);
-    }
-  }
-  if( sqlite3CheckCollSeq(pParse, pColl) ){ 
-    pColl = 0;
-  }
-  return pColl;
+static int checkSavepointCount(sqlite3 *db){
+  int n = 0;
+  Savepoint *p;
+  for(p=db->pSavepoint; p; p=p->pNext) n++;
+  assert( n==(db->nSavepoint + db->isTransactionSavepoint) );
+  return 1;
 }
+#endif
 
 /*
-** pExpr is an operand of a comparison operator.  aff2 is the
-** type affinity of the other operand.  This routine returns the
-** type affinity that should be used for the comparison operator.
-*/
-SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2){
-  char aff1 = sqlite3ExprAffinity(pExpr);
-  if( aff1 && aff2 ){
-    /* Both sides of the comparison are columns. If one has numeric
-    ** affinity, use that. Otherwise use no affinity.
-    */
-    if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){
-      return SQLITE_AFF_NUMERIC;
-    }else{
-      return SQLITE_AFF_NONE;
-    }
-  }else if( !aff1 && !aff2 ){
-    /* Neither side of the comparison is a column.  Compare the
-    ** results directly.
-    */
-    return SQLITE_AFF_NONE;
-  }else{
-    /* One side is a column, the other is not. Use the columns affinity. */
-    assert( aff1==0 || aff2==0 );
-    return (aff1 + aff2);
-  }
-}
-
-/*
-** pExpr is a comparison operator.  Return the type affinity that should
-** be applied to both operands prior to doing the comparison.
+** Execute as much of a VDBE program as we can then return.
+**
+** sqlite3VdbeMakeReady() must be called before this routine in order to
+** close the program with a final OP_Halt and to set up the callbacks
+** and the error message pointer.
+**
+** Whenever a row or result data is available, this routine will either
+** invoke the result callback (if there is one) or return with
+** SQLITE_ROW.
+**
+** If an attempt is made to open a locked database, then this routine
+** will either invoke the busy callback (if there is one) or it will
+** return SQLITE_BUSY.
+**
+** If an error occurs, an error message is written to memory obtained
+** from sqlite3_malloc() and p->zErrMsg is made to point to that memory.
+** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
+**
+** If the callback ever returns non-zero, then the program exits
+** immediately.  There will be no error message but the p->rc field is
+** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
+**
+** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
+** routine to return SQLITE_ERROR.
+**
+** Other fatal errors return SQLITE_ERROR.
+**
+** After this routine has finished, sqlite3VdbeFinalize() should be
+** used to clean up the mess that was left behind.
 */
-static char comparisonAffinity(Expr *pExpr){
-  char aff;
-  assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||
-          pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||
-          pExpr->op==TK_NE );
-  assert( pExpr->pLeft );
-  aff = sqlite3ExprAffinity(pExpr->pLeft);
-  if( pExpr->pRight ){
-    aff = sqlite3CompareAffinity(pExpr->pRight, aff);
+SQLITE_PRIVATE int sqlite3VdbeExec(
+  Vdbe *p                    /* The VDBE */
+){
+  int pc;                    /* The program counter */
+  Op *pOp;                   /* Current operation */
+  int rc = SQLITE_OK;        /* Value to return */
+  sqlite3 *db = p->db;       /* The database */
+  u8 encoding = ENC(db);     /* The database encoding */
+  Mem *pIn1 = 0;             /* 1st input operand */
+  Mem *pIn2 = 0;             /* 2nd input operand */
+  Mem *pIn3 = 0;             /* 3rd input operand */
+  Mem *pOut = 0;             /* Output operand */
+  u8 opProperty;
+  int iCompare = 0;          /* Result of last OP_Compare operation */
+  int *aPermute = 0;         /* Permutation of columns for OP_Compare */
+#ifdef VDBE_PROFILE
+  u64 start;                 /* CPU clock count at start of opcode */
+  int origPc;                /* Program counter at start of opcode */
+#endif
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
+#endif
+  /********************************************************************
+  ** Automatically generated code
+  **
+  ** The following union is automatically generated by the
+  ** vdbe-compress.tcl script.  The purpose of this union is to
+  ** reduce the amount of stack space required by this function.
+  ** See comments in the vdbe-compress.tcl script for details.
+  */
+  union vdbeExecUnion {
+    struct OP_Yield_stack_vars {
+      int pcDest;
+    } aa;
+    struct OP_Variable_stack_vars {
+      int p1;          /* Variable to copy from */
+      int p2;          /* Register to copy to */
+      int n;           /* Number of values left to copy */
+      Mem *pVar;       /* Value being transferred */
+    } ab;
+    struct OP_Move_stack_vars {
+      char *zMalloc;   /* Holding variable for allocated memory */
+      int n;           /* Number of registers left to copy */
+      int p1;          /* Register to copy from */
+      int p2;          /* Register to copy to */
+    } ac;
+    struct OP_ResultRow_stack_vars {
+      Mem *pMem;
+      int i;
+    } ad;
+    struct OP_Concat_stack_vars {
+      i64 nByte;
+    } ae;
+    struct OP_Remainder_stack_vars {
+      int flags;      /* Combined MEM_* flags from both inputs */
+      i64 iA;         /* Integer value of left operand */
+      i64 iB;         /* Integer value of right operand */
+      double rA;      /* Real value of left operand */
+      double rB;      /* Real value of right operand */
+    } af;
+    struct OP_Function_stack_vars {
+      int i;
+      Mem *pArg;
+      sqlite3_context ctx;
+      sqlite3_value **apVal;
+      int n;
+    } ag;
+    struct OP_ShiftRight_stack_vars {
+      i64 a;
+      i64 b;
+    } ah;
+    struct OP_Ge_stack_vars {
+      int res;            /* Result of the comparison of pIn1 against pIn3 */
+      char affinity;      /* Affinity to use for comparison */
+    } ai;
+    struct OP_Compare_stack_vars {
+      int n;
+      int i;
+      int p1;
+      int p2;
+      const KeyInfo *pKeyInfo;
+      int idx;
+      CollSeq *pColl;    /* Collating sequence to use on this term */
+      int bRev;          /* True for DESCENDING sort order */
+    } aj;
+    struct OP_Or_stack_vars {
+      int v1;    /* Left operand:  0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
+      int v2;    /* Right operand: 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
+    } ak;
+    struct OP_IfNot_stack_vars {
+      int c;
+    } al;
+    struct OP_Column_stack_vars {
+      u32 payloadSize;   /* Number of bytes in the record */
+      i64 payloadSize64; /* Number of bytes in the record */
+      int p1;            /* P1 value of the opcode */
+      int p2;            /* column number to retrieve */
+      VdbeCursor *pC;    /* The VDBE cursor */
+      char *zRec;        /* Pointer to complete record-data */
+      BtCursor *pCrsr;   /* The BTree cursor */
+      u32 *aType;        /* aType[i] holds the numeric type of the i-th column */
+      u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
+      int nField;        /* number of fields in the record */
+      int len;           /* The length of the serialized data for the column */
+      int i;             /* Loop counter */
+      char *zData;       /* Part of the record being decoded */
+      Mem *pDest;        /* Where to write the extracted value */
+      Mem sMem;          /* For storing the record being decoded */
+      u8 *zIdx;          /* Index into header */
+      u8 *zEndHdr;       /* Pointer to first byte after the header */
+      u32 offset;        /* Offset into the data */
+      u64 offset64;      /* 64-bit offset.  64 bits needed to catch overflow */
+      int szHdr;         /* Size of the header size field at start of record */
+      int avail;         /* Number of bytes of available data */
+      Mem *pReg;         /* PseudoTable input register */
+    } am;
+    struct OP_Affinity_stack_vars {
+      char *zAffinity;   /* The affinity to be applied */
+      Mem *pData0;       /* First register to which to apply affinity */
+      Mem *pLast;        /* Last register to which to apply affinity */
+      Mem *pRec;         /* Current register */
+    } an;
+    struct OP_MakeRecord_stack_vars {
+      u8 *zNewRecord;        /* A buffer to hold the data for the new record */
+      Mem *pRec;             /* The new record */
+      u64 nData;             /* Number of bytes of data space */
+      int nHdr;              /* Number of bytes of header space */
+      i64 nByte;             /* Data space required for this record */
+      int nZero;             /* Number of zero bytes at the end of the record */
+      int nVarint;           /* Number of bytes in a varint */
+      u32 serial_type;       /* Type field */
+      Mem *pData0;           /* First field to be combined into the record */
+      Mem *pLast;            /* Last field of the record */
+      int nField;            /* Number of fields in the record */
+      char *zAffinity;       /* The affinity string for the record */
+      int file_format;       /* File format to use for encoding */
+      int i;                 /* Space used in zNewRecord[] */
+      int len;               /* Length of a field */
+    } ao;
+    struct OP_Count_stack_vars {
+      i64 nEntry;
+      BtCursor *pCrsr;
+    } ap;
+    struct OP_Savepoint_stack_vars {
+      int p1;                         /* Value of P1 operand */
+      char *zName;                    /* Name of savepoint */
+      int nName;
+      Savepoint *pNew;
+      Savepoint *pSavepoint;
+      Savepoint *pTmp;
+      int iSavepoint;
+      int ii;
+    } aq;
+    struct OP_AutoCommit_stack_vars {
+      int desiredAutoCommit;
+      int iRollback;
+      int turnOnAC;
+    } ar;
+    struct OP_Transaction_stack_vars {
+      Btree *pBt;
+    } as;
+    struct OP_ReadCookie_stack_vars {
+      int iMeta;
+      int iDb;
+      int iCookie;
+    } at;
+    struct OP_SetCookie_stack_vars {
+      Db *pDb;
+    } au;
+    struct OP_VerifyCookie_stack_vars {
+      int iMeta;
+      Btree *pBt;
+    } av;
+    struct OP_OpenWrite_stack_vars {
+      int nField;
+      KeyInfo *pKeyInfo;
+      int p2;
+      int iDb;
+      int wrFlag;
+      Btree *pX;
+      VdbeCursor *pCur;
+      Db *pDb;
+    } aw;
+    struct OP_OpenEphemeral_stack_vars {
+      VdbeCursor *pCx;
+    } ax;
+    struct OP_OpenPseudo_stack_vars {
+      VdbeCursor *pCx;
+    } ay;
+    struct OP_SeekGt_stack_vars {
+      int res;
+      int oc;
+      VdbeCursor *pC;
+      UnpackedRecord r;
+      int nField;
+      i64 iKey;      /* The rowid we are to seek to */
+    } az;
+    struct OP_Seek_stack_vars {
+      VdbeCursor *pC;
+    } ba;
+    struct OP_Found_stack_vars {
+      int alreadyExists;
+      VdbeCursor *pC;
+      int res;
+      UnpackedRecord *pIdxKey;
+      char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*3 + 7];
+    } bb;
+    struct OP_IsUnique_stack_vars {
+      u16 ii;
+      VdbeCursor *pCx;
+      BtCursor *pCrsr;
+      u16 nField;
+      Mem *aMem;
+      UnpackedRecord r;                  /* B-Tree index search key */
+      i64 R;                             /* Rowid stored in register P3 */
+    } bc;
+    struct OP_NotExists_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int res;
+      u64 iKey;
+    } bd;
+    struct OP_NewRowid_stack_vars {
+      i64 v;                 /* The new rowid */
+      VdbeCursor *pC;        /* Cursor of table to get the new rowid */
+      int res;               /* Result of an sqlite3BtreeLast() */
+      int cnt;               /* Counter to limit the number of searches */
+      Mem *pMem;             /* Register holding largest rowid for AUTOINCREMENT */
+      VdbeFrame *pFrame;     /* Root frame of VDBE */
+    } be;
+    struct OP_Insert_stack_vars {
+      Mem *pData;       /* MEM cell holding data for the record to be inserted */
+      Mem *pKey;        /* MEM cell holding key  for the record */
+      i64 iKey;         /* The integer ROWID or key for the record to be inserted */
+      VdbeCursor *pC;   /* Cursor to table into which insert is written */
+      int nZero;        /* Number of zero-bytes to append */
+      int seekResult;   /* Result of prior seek or 0 if no USESEEKRESULT flag */
+      const char *zDb;  /* database name - used by the update hook */
+      const char *zTbl; /* Table name - used by the opdate hook */
+      int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */
+    } bf;
+    struct OP_Delete_stack_vars {
+      i64 iKey;
+      VdbeCursor *pC;
+    } bg;
+    struct OP_RowData_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      u32 n;
+      i64 n64;
+    } bh;
+    struct OP_Rowid_stack_vars {
+      VdbeCursor *pC;
+      i64 v;
+      sqlite3_vtab *pVtab;
+      const sqlite3_module *pModule;
+    } bi;
+    struct OP_NullRow_stack_vars {
+      VdbeCursor *pC;
+    } bj;
+    struct OP_Last_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int res;
+    } bk;
+    struct OP_Rewind_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int res;
+    } bl;
+    struct OP_Next_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int res;
+    } bm;
+    struct OP_IdxInsert_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int nKey;
+      const char *zKey;
+    } bn;
+    struct OP_IdxDelete_stack_vars {
+      VdbeCursor *pC;
+      BtCursor *pCrsr;
+      int res;
+      UnpackedRecord r;
+    } bo;
+    struct OP_IdxRowid_stack_vars {
+      BtCursor *pCrsr;
+      VdbeCursor *pC;
+      i64 rowid;
+    } bp;
+    struct OP_IdxGE_stack_vars {
+      VdbeCursor *pC;
+      int res;
+      UnpackedRecord r;
+    } bq;
+    struct OP_Destroy_stack_vars {
+      int iMoved;
+      int iCnt;
+      Vdbe *pVdbe;
+      int iDb;
+    } br;
+    struct OP_Clear_stack_vars {
+      int nChange;
+    } bs;
+    struct OP_CreateTable_stack_vars {
+      int pgno;
+      int flags;
+      Db *pDb;
+    } bt;
+    struct OP_ParseSchema_stack_vars {
+      int iDb;
+      const char *zMaster;
+      char *zSql;
+      InitData initData;
+    } bu;
+    struct OP_IntegrityCk_stack_vars {
+      int nRoot;      /* Number of tables to check.  (Number of root pages.) */
+      int *aRoot;     /* Array of rootpage numbers for tables to be checked */
+      int j;          /* Loop counter */
+      int nErr;       /* Number of errors reported */
+      char *z;        /* Text of the error report */
+      Mem *pnErr;     /* Register keeping track of errors remaining */
+    } bv;
+    struct OP_RowSetAdd_stack_vars {
+      Mem *pIdx;
+      Mem *pVal;
+    } bw;
+    struct OP_RowSetRead_stack_vars {
+      Mem *pIdx;
+      i64 val;
+    } bx;
+    struct OP_RowSetTest_stack_vars {
+      int iSet;
+      int exists;
+    } by;
+    struct OP_Program_stack_vars {
+      int nMem;               /* Number of memory registers for sub-program */
+      int nByte;              /* Bytes of runtime space required for sub-program */
+      Mem *pRt;               /* Register to allocate runtime space */
+      Mem *pMem;              /* Used to iterate through memory cells */
+      Mem *pEnd;              /* Last memory cell in new array */
+      VdbeFrame *pFrame;      /* New vdbe frame to execute in */
+      SubProgram *pProgram;   /* Sub-program to execute */
+      void *t;                /* Token identifying trigger */
+    } bz;
+    struct OP_Param_stack_vars {
+      VdbeFrame *pFrame;
+      Mem *pIn;
+    } ca;
+    struct OP_MemMax_stack_vars {
+      Mem *pIn1;
+      VdbeFrame *pFrame;
+    } cb;
+    struct OP_AggStep_stack_vars {
+      int n;
+      int i;
+      Mem *pMem;
+      Mem *pRec;
+      sqlite3_context ctx;
+      sqlite3_value **apVal;
+    } cc;
+    struct OP_AggFinal_stack_vars {
+      Mem *pMem;
+    } cd;
+    struct OP_IncrVacuum_stack_vars {
+      Btree *pBt;
+    } ce;
+    struct OP_VBegin_stack_vars {
+      VTable *pVTab;
+    } cf;
+    struct OP_VOpen_stack_vars {
+      VdbeCursor *pCur;
+      sqlite3_vtab_cursor *pVtabCursor;
+      sqlite3_vtab *pVtab;
+      sqlite3_module *pModule;
+    } cg;
+    struct OP_VFilter_stack_vars {
+      int nArg;
+      int iQuery;
+      const sqlite3_module *pModule;
+      Mem *pQuery;
+      Mem *pArgc;
+      sqlite3_vtab_cursor *pVtabCursor;
+      sqlite3_vtab *pVtab;
+      VdbeCursor *pCur;
+      int res;
+      int i;
+      Mem **apArg;
+    } ch;
+    struct OP_VColumn_stack_vars {
+      sqlite3_vtab *pVtab;
+      const sqlite3_module *pModule;
+      Mem *pDest;
+      sqlite3_context sContext;
+    } ci;
+    struct OP_VNext_stack_vars {
+      sqlite3_vtab *pVtab;
+      const sqlite3_module *pModule;
+      int res;
+      VdbeCursor *pCur;
+    } cj;
+    struct OP_VRename_stack_vars {
+      sqlite3_vtab *pVtab;
+      Mem *pName;
+    } ck;
+    struct OP_VUpdate_stack_vars {
+      sqlite3_vtab *pVtab;
+      sqlite3_module *pModule;
+      int nArg;
+      int i;
+      sqlite_int64 rowid;
+      Mem **apArg;
+      Mem *pX;
+    } cl;
+    struct OP_Pagecount_stack_vars {
+      int p1;
+      int nPage;
+      Pager *pPager;
+    } cm;
+    struct OP_Trace_stack_vars {
+      char *zTrace;
+    } cn;
+  } u;
+  /* End automatically generated code
+  ********************************************************************/
+
+  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
+  assert( db->magic==SQLITE_MAGIC_BUSY );
+  sqlite3VdbeMutexArrayEnter(p);
+  if( p->rc==SQLITE_NOMEM ){
+    /* This happens if a malloc() inside a call to sqlite3_column_text() or
+    ** sqlite3_column_text16() failed.  */
+    goto no_mem;
   }
-  else if( pExpr->pSelect ){
-    aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff);
+  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
+  p->rc = SQLITE_OK;
+  assert( p->explain==0 );
+  p->pResultSet = 0;
+  db->busyHandler.nBusy = 0;
+  CHECK_FOR_INTERRUPT;
+  sqlite3VdbeIOTraceSql(p);
+#ifdef SQLITE_DEBUG
+  sqlite3BeginBenignMalloc();
+  if( p->pc==0 
+   && ((p->db->flags & SQLITE_VdbeListing) || fileExists(db, "vdbe_explain"))
+  ){
+    int i;
+    printf("VDBE Program Listing:\n");
+    sqlite3VdbePrintSql(p);
+    for(i=0; i<p->nOp; i++){
+      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
+    }
   }
-  else if( !aff ){
-    aff = SQLITE_AFF_NONE;
+  if( fileExists(db, "vdbe_trace") ){
+    p->trace = stdout;
   }
-  return aff;
-}
+  sqlite3EndBenignMalloc();
+#endif
+  for(pc=p->pc; rc==SQLITE_OK; pc++){
+    assert( pc>=0 && pc<p->nOp );
+    if( db->mallocFailed ) goto no_mem;
+#ifdef VDBE_PROFILE
+    origPc = pc;
+    start = sqlite3Hwtime();
+#endif
+    pOp = &p->aOp[pc];
 
-/*
-** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
-** idx_affinity is the affinity of an indexed column. Return true
-** if the index with affinity idx_affinity may be used to implement
-** the comparison in pExpr.
+    /* Only allow tracing if SQLITE_DEBUG is defined.
+    */
+#ifdef SQLITE_DEBUG
+    if( p->trace ){
+      if( pc==0 ){
+        printf("VDBE Execution Trace:\n");
+        sqlite3VdbePrintSql(p);
+      }
+      sqlite3VdbePrintOp(p->trace, pc, pOp);
+    }
+    if( p->trace==0 && pc==0 ){
+      sqlite3BeginBenignMalloc();
+      if( fileExists(db, "vdbe_sqltrace") ){
+        sqlite3VdbePrintSql(p);
+      }
+      sqlite3EndBenignMalloc();
+    }
+#endif
+      
+
+    /* Check to see if we need to simulate an interrupt.  This only happens
+    ** if we have a special test build.
+    */
+#ifdef SQLITE_TEST
+    if( sqlite3_interrupt_count>0 ){
+      sqlite3_interrupt_count--;
+      if( sqlite3_interrupt_count==0 ){
+        sqlite3_interrupt(db);
+      }
+    }
+#endif
+
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+    /* Call the progress callback if it is configured and the required number
+    ** of VDBE ops have been executed (either since this invocation of
+    ** sqlite3VdbeExec() or since last time the progress callback was called).
+    ** If the progress callback returns non-zero, exit the virtual machine with
+    ** a return code SQLITE_ABORT.
+    */
+    if( db->xProgress ){
+      if( db->nProgressOps==nProgressOps ){
+        int prc;
+        if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+        prc =db->xProgress(db->pProgressArg);
+        if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+        if( prc!=0 ){
+          rc = SQLITE_INTERRUPT;
+          goto vdbe_error_halt;
+        }
+        nProgressOps = 0;
+      }
+      nProgressOps++;
+    }
+#endif
+
+    /* Do common setup processing for any opcode that is marked
+    ** with the "out2-prerelease" tag.  Such opcodes have a single
+    ** output which is specified by the P2 parameter.  The P2 register
+    ** is initialized to a NULL.
+    */
+    opProperty = opcodeProperty[pOp->opcode];
+    if( (opProperty & OPFLG_OUT2_PRERELEASE)!=0 ){
+      assert( pOp->p2>0 );
+      assert( pOp->p2<=p->nMem );
+      pOut = &p->aMem[pOp->p2];
+      sqlite3VdbeMemReleaseExternal(pOut);
+      pOut->flags = MEM_Null;
+      pOut->n = 0;
+    }else
+ 
+    /* Do common setup for opcodes marked with one of the following
+    ** combinations of properties.
+    **
+    **           in1
+    **           in1 in2
+    **           in1 in2 out3
+    **           in1 in3
+    **
+    ** Variables pIn1, pIn2, and pIn3 are made to point to appropriate
+    ** registers for inputs.  Variable pOut points to the output register.
+    */
+    if( (opProperty & OPFLG_IN1)!=0 ){
+      assert( pOp->p1>0 );
+      assert( pOp->p1<=p->nMem );
+      pIn1 = &p->aMem[pOp->p1];
+      REGISTER_TRACE(pOp->p1, pIn1);
+      if( (opProperty & OPFLG_IN2)!=0 ){
+        assert( pOp->p2>0 );
+        assert( pOp->p2<=p->nMem );
+        pIn2 = &p->aMem[pOp->p2];
+        REGISTER_TRACE(pOp->p2, pIn2);
+        /* As currently implemented, in2 implies out3.  There is no reason
+        ** why this has to be, it just worked out that way. */
+        assert( (opProperty & OPFLG_OUT3)!=0 );
+        assert( pOp->p3>0 );
+        assert( pOp->p3<=p->nMem );
+        pOut = &p->aMem[pOp->p3];
+      }else if( (opProperty & OPFLG_IN3)!=0 ){
+        assert( pOp->p3>0 );
+        assert( pOp->p3<=p->nMem );
+        pIn3 = &p->aMem[pOp->p3];
+        REGISTER_TRACE(pOp->p3, pIn3);
+      }
+    }else if( (opProperty & OPFLG_IN2)!=0 ){
+      assert( pOp->p2>0 );
+      assert( pOp->p2<=p->nMem );
+      pIn2 = &p->aMem[pOp->p2];
+      REGISTER_TRACE(pOp->p2, pIn2);
+    }else if( (opProperty & OPFLG_IN3)!=0 ){
+      assert( pOp->p3>0 );
+      assert( pOp->p3<=p->nMem );
+      pIn3 = &p->aMem[pOp->p3];
+      REGISTER_TRACE(pOp->p3, pIn3);
+    }
+
+    switch( pOp->opcode ){
+
+/*****************************************************************************
+** What follows is a massive switch statement where each case implements a
+** separate instruction in the virtual machine.  If we follow the usual
+** indentation conventions, each case should be indented by 6 spaces.  But
+** that is a lot of wasted space on the left margin.  So the code within
+** the switch statement will break with convention and be flush-left. Another
+** big comment (similar to this one) will mark the point in the code where
+** we transition back to normal indentation.
+**
+** The formatting of each case is important.  The makefile for SQLite
+** generates two C files "opcodes.h" and "opcodes.c" by scanning this
+** file looking for lines that begin with "case OP_".  The opcodes.h files
+** will be filled with #defines that give unique integer values to each
+** opcode and the opcodes.c file is filled with an array of strings where
+** each string is the symbolic name for the corresponding opcode.  If the
+** case statement is followed by a comment of the form "/# same as ... #/"
+** that comment is used to determine the particular value of the opcode.
+**
+** Other keywords in the comment that follows each case are used to
+** construct the OPFLG_INITIALIZER value that initializes opcodeProperty[].
+** Keywords include: in1, in2, in3, out2_prerelease, out2, out3.  See
+** the mkopcodeh.awk script for additional information.
+**
+** Documentation about VDBE opcodes is generated by scanning this file
+** for lines of that contain "Opcode:".  That line and all subsequent
+** comment lines are used in the generation of the opcode.html documentation
+** file.
+**
+** SUMMARY:
+**
+**     Formatting is important to scripts that scan this file.
+**     Do not deviate from the formatting style currently in use.
+**
+*****************************************************************************/
+
+/* Opcode:  Goto * P2 * * *
+**
+** An unconditional jump to address P2.
+** The next instruction executed will be 
+** the one at index P2 from the beginning of
+** the program.
 */
-SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){
-  char aff = comparisonAffinity(pExpr);
-  switch( aff ){
-    case SQLITE_AFF_NONE:
-      return 1;
-    case SQLITE_AFF_TEXT:
-      return idx_affinity==SQLITE_AFF_TEXT;
-    default:
-      return sqlite3IsNumericAffinity(idx_affinity);
-  }
+case OP_Goto: {             /* jump */
+  CHECK_FOR_INTERRUPT;
+  pc = pOp->p2 - 1;
+  break;
 }
 
-/*
-** Return the P5 value that should be used for a binary comparison
-** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
+/* Opcode:  Gosub P1 P2 * * *
+**
+** Write the current address onto register P1
+** and then jump to address P2.
 */
-static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){
-  u8 aff = (char)sqlite3ExprAffinity(pExpr2);
-  aff = sqlite3CompareAffinity(pExpr1, aff) | jumpIfNull;
-  return aff;
+case OP_Gosub: {            /* jump */
+  assert( pOp->p1>0 );
+  assert( pOp->p1<=p->nMem );
+  pIn1 = &p->aMem[pOp->p1];
+  assert( (pIn1->flags & MEM_Dyn)==0 );
+  pIn1->flags = MEM_Int;
+  pIn1->u.i = pc;
+  REGISTER_TRACE(pOp->p1, pIn1);
+  pc = pOp->p2 - 1;
+  break;
 }
 
-/*
-** Return a pointer to the collation sequence that should be used by
-** a binary comparison operator comparing pLeft and pRight.
-**
-** If the left hand expression has a collating sequence type, then it is
-** used. Otherwise the collation sequence for the right hand expression
-** is used, or the default (BINARY) if neither expression has a collating
-** type.
+/* Opcode:  Return P1 * * * *
 **
-** Argument pRight (but not pLeft) may be a null pointer. In this case,
-** it is not considered.
+** Jump to the next instruction after the address in register P1.
 */
-SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(
-  Parse *pParse, 
-  Expr *pLeft, 
-  Expr *pRight
-){
-  CollSeq *pColl;
-  assert( pLeft );
-  if( pLeft->flags & EP_ExpCollate ){
-    assert( pLeft->pColl );
-    pColl = pLeft->pColl;
-  }else if( pRight && pRight->flags & EP_ExpCollate ){
-    assert( pRight->pColl );
-    pColl = pRight->pColl;
-  }else{
-    pColl = sqlite3ExprCollSeq(pParse, pLeft);
-    if( !pColl ){
-      pColl = sqlite3ExprCollSeq(pParse, pRight);
-    }
-  }
-  return pColl;
+case OP_Return: {           /* in1 */
+  assert( pIn1->flags & MEM_Int );
+  pc = (int)pIn1->u.i;
+  break;
 }
 
-/*
-** Generate the operands for a comparison operation.  Before
-** generating the code for each operand, set the EP_AnyAff
-** flag on the expression so that it will be able to used a
-** cached column value that has previously undergone an
-** affinity change.
+/* Opcode:  Yield P1 * * * *
+**
+** Swap the program counter with the value in register P1.
 */
-static void codeCompareOperands(
-  Parse *pParse,    /* Parsing and code generating context */
-  Expr *pLeft,      /* The left operand */
-  int *pRegLeft,    /* Register where left operand is stored */
-  int *pFreeLeft,   /* Free this register when done */
-  Expr *pRight,     /* The right operand */
-  int *pRegRight,   /* Register where right operand is stored */
-  int *pFreeRight   /* Write temp register for right operand there */
-){
-  while( pLeft->op==TK_UPLUS ) pLeft = pLeft->pLeft;
-  pLeft->flags |= EP_AnyAff;
-  *pRegLeft = sqlite3ExprCodeTemp(pParse, pLeft, pFreeLeft);
-  while( pRight->op==TK_UPLUS ) pRight = pRight->pLeft;
-  pRight->flags |= EP_AnyAff;
-  *pRegRight = sqlite3ExprCodeTemp(pParse, pRight, pFreeRight);
+case OP_Yield: {            /* in1 */
+#if 0  /* local variables moved into u.aa */
+  int pcDest;
+#endif /* local variables moved into u.aa */
+  assert( (pIn1->flags & MEM_Dyn)==0 );
+  pIn1->flags = MEM_Int;
+  u.aa.pcDest = (int)pIn1->u.i;
+  pIn1->u.i = pc;
+  REGISTER_TRACE(pOp->p1, pIn1);
+  pc = u.aa.pcDest;
+  break;
 }
 
-/*
-** Generate code for a comparison operator.
+/* Opcode:  HaltIfNull  P1 P2 P3 P4 *
+**
+** Check the value in register P3.  If is is NULL then Halt using
+** parameter P1, P2, and P4 as if this were a Halt instruction.  If the
+** value in register P3 is not NULL, then this routine is a no-op.
 */
-static int codeCompare(
-  Parse *pParse,    /* The parsing (and code generating) context */
-  Expr *pLeft,      /* The left operand */
-  Expr *pRight,     /* The right operand */
-  int opcode,       /* The comparison opcode */
-  int in1, int in2, /* Register holding operands */
-  int dest,         /* Jump here if true.  */
-  int jumpIfNull    /* If true, jump if either operand is NULL */
-){
-  int p5;
-  int addr;
-  CollSeq *p4;
-
-  p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
-  p5 = binaryCompareP5(pLeft, pRight, jumpIfNull);
-  addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1,
-                           (void*)p4, P4_COLLSEQ);
-  sqlite3VdbeChangeP5(pParse->pVdbe, p5);
-  if( p5 & SQLITE_AFF_MASK ){
-    sqlite3ExprCacheAffinityChange(pParse, in1, 1);
-    sqlite3ExprCacheAffinityChange(pParse, in2, 1);
-  }
-  return addr;
+case OP_HaltIfNull: {      /* in3 */
+  if( (pIn3->flags & MEM_Null)==0 ) break;
+  /* Fall through into OP_Halt */
 }
 
-/*
-** Construct a new expression node and return a pointer to it.  Memory
-** for this node is obtained from sqlite3_malloc().  The calling function
-** is responsible for making sure the node eventually gets freed.
+/* Opcode:  Halt P1 P2 * P4 *
+**
+** Exit immediately.  All open cursors, etc are closed
+** automatically.
+**
+** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
+** or sqlite3_finalize().  For a normal halt, this should be SQLITE_OK (0).
+** For errors, it can be some other value.  If P1!=0 then P2 will determine
+** whether or not to rollback the current transaction.  Do not rollback
+** if P2==OE_Fail. Do the rollback if P2==OE_Rollback.  If P2==OE_Abort,
+** then back out all changes that have occurred during this execution of the
+** VDBE, but do not rollback the transaction. 
+**
+** If P4 is not null then it is an error message string.
+**
+** There is an implied "Halt 0 0 0" instruction inserted at the very end of
+** every program.  So a jump past the last instruction of the program
+** is the same as executing Halt.
 */
-SQLITE_PRIVATE Expr *sqlite3Expr(
-  sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */
-  int op,                 /* Expression opcode */
-  Expr *pLeft,            /* Left operand */
-  Expr *pRight,           /* Right operand */
-  const Token *pToken     /* Argument token */
-){
-  Expr *pNew;
-  pNew = sqlite3DbMallocZero(db, sizeof(Expr));
-  if( pNew==0 ){
-    /* When malloc fails, delete pLeft and pRight. Expressions passed to 
-    ** this function must always be allocated with sqlite3Expr() for this 
-    ** reason. 
-    */
-    sqlite3ExprDelete(pLeft);
-    sqlite3ExprDelete(pRight);
-    return 0;
-  }
-  pNew->op = op;
-  pNew->pLeft = pLeft;
-  pNew->pRight = pRight;
-  pNew->iAgg = -1;
-  if( pToken ){
-    assert( pToken->dyn==0 );
-    pNew->span = pNew->token = *pToken;
-  }else if( pLeft ){
-    if( pRight ){
-      sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span);
-      if( pRight->flags & EP_ExpCollate ){
-        pNew->flags |= EP_ExpCollate;
-        pNew->pColl = pRight->pColl;
-      }
-    }
-    if( pLeft->flags & EP_ExpCollate ){
-      pNew->flags |= EP_ExpCollate;
-      pNew->pColl = pLeft->pColl;
+case OP_Halt: {
+  if( pOp->p1==SQLITE_OK && p->pFrame ){
+    /* Halt the sub-program. Return control to the parent frame. */
+    VdbeFrame *pFrame = p->pFrame;
+    p->pFrame = pFrame->pParent;
+    p->nFrame--;
+    sqlite3VdbeSetChanges(db, p->nChange);
+    pc = sqlite3VdbeFrameRestore(pFrame);
+    if( pOp->p2==OE_Ignore ){
+      /* Instruction pc is the OP_Program that invoked the sub-program 
+      ** currently being halted. If the p2 instruction of this OP_Halt
+      ** instruction is set to OE_Ignore, then the sub-program is throwing
+      ** an IGNORE exception. In this case jump to the address specified
+      ** as the p2 of the calling OP_Program.  */
+      pc = p->aOp[pc].p2-1;
     }
+    break;
   }
 
-  sqlite3ExprSetHeight(pNew);
-  return pNew;
+  p->rc = pOp->p1;
+  p->errorAction = (u8)pOp->p2;
+  p->pc = pc;
+  if( pOp->p4.z ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", pOp->p4.z);
+  }
+  rc = sqlite3VdbeHalt(p);
+  assert( rc==SQLITE_BUSY || rc==SQLITE_OK || rc==SQLITE_ERROR );
+  if( rc==SQLITE_BUSY ){
+    p->rc = rc = SQLITE_BUSY;
+  }else{
+    assert( rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT );
+    assert( rc==SQLITE_OK || db->nDeferredCons>0 );
+    rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
+  }
+  goto vdbe_return;
 }
 
-/*
-** Works like sqlite3Expr() except that it takes an extra Parse*
-** argument and notifies the associated connection object if malloc fails.
+/* Opcode: Integer P1 P2 * * *
+**
+** The 32-bit integer value P1 is written into register P2.
 */
-SQLITE_PRIVATE Expr *sqlite3PExpr(
-  Parse *pParse,          /* Parsing context */
-  int op,                 /* Expression opcode */
-  Expr *pLeft,            /* Left operand */
-  Expr *pRight,           /* Right operand */
-  const Token *pToken     /* Argument token */
-){
-  return sqlite3Expr(pParse->db, op, pLeft, pRight, pToken);
+case OP_Integer: {         /* out2-prerelease */
+  pOut->flags = MEM_Int;
+  pOut->u.i = pOp->p1;
+  break;
 }
 
-/*
-** When doing a nested parse, you can include terms in an expression
-** that look like this:   #1 #2 ...  These terms refer to registers
-** in the virtual machine.  #N is the N-th register.
+/* Opcode: Int64 * P2 * P4 *
 **
-** This routine is called by the parser to deal with on of those terms.
-** It immediately generates code to store the value in a memory location.
-** The returns an expression that will code to extract the value from
-** that memory location as needed.
+** P4 is a pointer to a 64-bit integer value.
+** Write that value into register P2.
 */
-SQLITE_PRIVATE Expr *sqlite3RegisterExpr(Parse *pParse, Token *pToken){
-  Vdbe *v = pParse->pVdbe;
-  Expr *p;
-  if( pParse->nested==0 ){
-    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);
-    return sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
-  }
-  if( v==0 ) return 0;
-  p = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, pToken);
-  if( p==0 ){
-    return 0;  /* Malloc failed */
-  }
-  p->iTable = atoi((char*)&pToken->z[1]);
-  return p;
+case OP_Int64: {           /* out2-prerelease */
+  assert( pOp->p4.pI64!=0 );
+  pOut->flags = MEM_Int;
+  pOut->u.i = *pOp->p4.pI64;
+  break;
 }
 
-/*
-** Join two expressions using an AND operator.  If either expression is
-** NULL, then just return the other expression.
+/* Opcode: Real * P2 * P4 *
+**
+** P4 is a pointer to a 64-bit floating point value.
+** Write that value into register P2.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){
-  if( pLeft==0 ){
-    return pRight;
-  }else if( pRight==0 ){
-    return pLeft;
-  }else{
-    return sqlite3Expr(db, TK_AND, pLeft, pRight, 0);
-  }
+case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
+  pOut->flags = MEM_Real;
+  assert( !sqlite3IsNaN(*pOp->p4.pReal) );
+  pOut->r = *pOp->p4.pReal;
+  break;
 }
 
-/*
-** Set the Expr.span field of the given expression to span all
-** text between the two given tokens.
+/* Opcode: String8 * P2 * P4 *
+**
+** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
+** into an OP_String before it is executed for the first time.
 */
-SQLITE_PRIVATE void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
-  assert( pRight!=0 );
-  assert( pLeft!=0 );
-  if( pExpr && pRight->z && pLeft->z ){
-    assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 );
-    if( pLeft->dyn==0 && pRight->dyn==0 ){
-      pExpr->span.z = pLeft->z;
-      pExpr->span.n = pRight->n + (pRight->z - pLeft->z);
-    }else{
-      pExpr->span.z = 0;
+case OP_String8: {         /* same as TK_STRING, out2-prerelease */
+  assert( pOp->p4.z!=0 );
+  pOp->opcode = OP_String;
+  pOp->p1 = sqlite3Strlen30(pOp->p4.z);
+
+#ifndef SQLITE_OMIT_UTF16
+  if( encoding!=SQLITE_UTF8 ){
+    rc = sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
+    if( rc==SQLITE_TOOBIG ) goto too_big;
+    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
+    assert( pOut->zMalloc==pOut->z );
+    assert( pOut->flags & MEM_Dyn );
+    pOut->zMalloc = 0;
+    pOut->flags |= MEM_Static;
+    pOut->flags &= ~MEM_Dyn;
+    if( pOp->p4type==P4_DYNAMIC ){
+      sqlite3DbFree(db, pOp->p4.z);
     }
+    pOp->p4type = P4_DYNAMIC;
+    pOp->p4.z = pOut->z;
+    pOp->p1 = pOut->n;
+  }
+#endif
+  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    goto too_big;
   }
+  /* Fall through to the next case, OP_String */
 }
-
-/*
-** Construct a new expression node for a function with multiple
-** arguments.
+  
+/* Opcode: String P1 P2 * P4 *
+**
+** The string value P4 of length P1 (bytes) is stored in register P2.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){
-  Expr *pNew;
-  assert( pToken );
-  pNew = sqlite3DbMallocZero(pParse->db, sizeof(Expr) );
-  if( pNew==0 ){
-    sqlite3ExprListDelete(pList); /* Avoid leaking memory when malloc fails */
-    return 0;
-  }
-  pNew->op = TK_FUNCTION;
-  pNew->pList = pList;
-  assert( pToken->dyn==0 );
-  pNew->token = *pToken;
-  pNew->span = pNew->token;
-
-  sqlite3ExprSetHeight(pNew);
-  return pNew;
+case OP_String: {          /* out2-prerelease */
+  assert( pOp->p4.z!=0 );
+  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
+  pOut->z = pOp->p4.z;
+  pOut->n = pOp->p1;
+  pOut->enc = encoding;
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
 }
 
-/*
-** Assign a variable number to an expression that encodes a wildcard
-** in the original SQL statement.  
-**
-** Wildcards consisting of a single "?" are assigned the next sequential
-** variable number.
-**
-** Wildcards of the form "?nnn" are assigned the number "nnn".  We make
-** sure "nnn" is not too be to avoid a denial of service attack when
-** the SQL statement comes from an external source.
+/* Opcode: Null * P2 * * *
 **
-** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
-** as the previous instance of the same wildcard.  Or if this is the first
-** instance of the wildcard, the next sequenial variable number is
-** assigned.
+** Write a NULL into register P2.
 */
-SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
-  Token *pToken;
-  sqlite3 *db = pParse->db;
-
-  if( pExpr==0 ) return;
-  pToken = &pExpr->token;
-  assert( pToken->n>=1 );
-  assert( pToken->z!=0 );
-  assert( pToken->z[0]!=0 );
-  if( pToken->n==1 ){
-    /* Wildcard of the form "?".  Assign the next variable number */
-    pExpr->iTable = ++pParse->nVar;
-  }else if( pToken->z[0]=='?' ){
-    /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
-    ** use it as the variable number */
-    int i;
-    pExpr->iTable = i = atoi((char*)&pToken->z[1]);
-    testcase( i==0 );
-    testcase( i==1 );
-    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
-    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
-    if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
-      sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
-          db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
-    }
-    if( i>pParse->nVar ){
-      pParse->nVar = i;
-    }
-  }else{
-    /* Wildcards of the form ":aaa" or "$aaa".  Reuse the same variable
-    ** number as the prior appearance of the same name, or if the name
-    ** has never appeared before, reuse the same variable number
-    */
-    int i, n;
-    n = pToken->n;
-    for(i=0; i<pParse->nVarExpr; i++){
-      Expr *pE;
-      if( (pE = pParse->apVarExpr[i])!=0
-          && pE->token.n==n
-          && memcmp(pE->token.z, pToken->z, n)==0 ){
-        pExpr->iTable = pE->iTable;
-        break;
-      }
-    }
-    if( i>=pParse->nVarExpr ){
-      pExpr->iTable = ++pParse->nVar;
-      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
-        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
-        pParse->apVarExpr =
-            sqlite3DbReallocOrFree(
-              db,
-              pParse->apVarExpr,
-              pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
-            );
-      }
-      if( !db->mallocFailed ){
-        assert( pParse->apVarExpr!=0 );
-        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
-      }
-    }
-  } 
-  if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
-    sqlite3ErrorMsg(pParse, "too many SQL variables");
-  }
+case OP_Null: {           /* out2-prerelease */
+  break;
 }
 
-/*
-** Recursively delete an expression tree.
-*/
-SQLITE_PRIVATE void sqlite3ExprDelete(Expr *p){
-  if( p==0 ) return;
-  if( p->span.dyn ) sqlite3_free((char*)p->span.z);
-  if( p->token.dyn ) sqlite3_free((char*)p->token.z);
-  sqlite3ExprDelete(p->pLeft);
-  sqlite3ExprDelete(p->pRight);
-  sqlite3ExprListDelete(p->pList);
-  sqlite3SelectDelete(p->pSelect);
-  sqlite3_free(p);
-}
 
-/*
-** The Expr.token field might be a string literal that is quoted.
-** If so, remove the quotation marks.
+/* Opcode: Blob P1 P2 * P4
+**
+** P4 points to a blob of data P1 bytes long.  Store this
+** blob in register P2. This instruction is not coded directly
+** by the compiler. Instead, the compiler layer specifies
+** an OP_HexBlob opcode, with the hex string representation of
+** the blob as P4. This opcode is transformed to an OP_Blob
+** the first time it is executed.
 */
-SQLITE_PRIVATE void sqlite3DequoteExpr(sqlite3 *db, Expr *p){
-  if( ExprHasAnyProperty(p, EP_Dequoted) ){
-    return;
-  }
-  ExprSetProperty(p, EP_Dequoted);
-  if( p->token.dyn==0 ){
-    sqlite3TokenCopy(db, &p->token, &p->token);
-  }
-  sqlite3Dequote((char*)p->token.z);
+case OP_Blob: {                /* out2-prerelease */
+  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
+  sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
+  pOut->enc = encoding;
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
 }
 
-
-/*
-** The following group of routines make deep copies of expressions,
-** expression lists, ID lists, and select statements.  The copies can
-** be deleted (by being passed to their respective ...Delete() routines)
-** without effecting the originals.
+/* Opcode: Variable P1 P2 P3 P4 *
 **
-** The expression list, ID, and source lists return by sqlite3ExprListDup(),
-** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
-** by subsequent calls to sqlite*ListAppend() routines.
+** Transfer the values of bound parameters P1..P1+P3-1 into registers
+** P2..P2+P3-1.
 **
-** Any tables that the SrcList might point to are not duplicated.
-*/
-SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3 *db, Expr *p){
-  Expr *pNew;
-  if( p==0 ) return 0;
-  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
-  if( pNew==0 ) return 0;
-  memcpy(pNew, p, sizeof(*pNew));
-  if( p->token.z!=0 ){
-    pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
-    pNew->token.dyn = 1;
-  }else{
-    assert( pNew->token.z==0 );
-  }
-  pNew->span.z = 0;
-  pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
-  pNew->pRight = sqlite3ExprDup(db, p->pRight);
-  pNew->pList = sqlite3ExprListDup(db, p->pList);
-  pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
-  return pNew;
-}
-SQLITE_PRIVATE void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
-  if( pTo->dyn ) sqlite3_free((char*)pTo->z);
-  if( pFrom->z ){
-    pTo->n = pFrom->n;
-    pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
-    pTo->dyn = 1;
-  }else{
-    pTo->z = 0;
-  }
-}
-SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
-  ExprList *pNew;
-  struct ExprList_item *pItem, *pOldItem;
-  int i;
-  if( p==0 ) return 0;
-  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
-  if( pNew==0 ) return 0;
-  pNew->iECursor = 0;
-  pNew->nExpr = pNew->nAlloc = p->nExpr;
-  pNew->a = pItem = sqlite3DbMallocRaw(db,  p->nExpr*sizeof(p->a[0]) );
-  if( pItem==0 ){
-    sqlite3_free(pNew);
-    return 0;
-  } 
-  pOldItem = p->a;
-  for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
-    Expr *pNewExpr, *pOldExpr;
-    pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
-    if( pOldExpr->span.z!=0 && pNewExpr ){
-      /* Always make a copy of the span for top-level expressions in the
-      ** expression list.  The logic in SELECT processing that determines
-      ** the names of columns in the result set needs this information */
-      sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
-    }
-    assert( pNewExpr==0 || pNewExpr->span.z!=0 
-            || pOldExpr->span.z==0
-            || db->mallocFailed );
-    pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
-    pItem->sortOrder = pOldItem->sortOrder;
-    pItem->isAgg = pOldItem->isAgg;
-    pItem->done = 0;
-  }
-  return pNew;
-}
-
-/*
-** If cursors, triggers, views and subqueries are all omitted from
-** the build, then none of the following routines, except for 
-** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
-** called with a NULL argument.
+** If the parameter is named, then its name appears in P4 and P3==1.
+** The P4 value is used by sqlite3_bind_parameter_name().
 */
-#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
- || !defined(SQLITE_OMIT_SUBQUERY)
-SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){
-  SrcList *pNew;
-  int i;
-  int nByte;
-  if( p==0 ) return 0;
-  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
-  pNew = sqlite3DbMallocRaw(db, nByte );
-  if( pNew==0 ) return 0;
-  pNew->nSrc = pNew->nAlloc = p->nSrc;
-  for(i=0; i<p->nSrc; i++){
-    struct SrcList_item *pNewItem = &pNew->a[i];
-    struct SrcList_item *pOldItem = &p->a[i];
-    Table *pTab;
-    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
-    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
-    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
-    pNewItem->jointype = pOldItem->jointype;
-    pNewItem->iCursor = pOldItem->iCursor;
-    pNewItem->isPopulated = pOldItem->isPopulated;
-    pTab = pNewItem->pTab = pOldItem->pTab;
-    if( pTab ){
-      pTab->nRef++;
-    }
-    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
-    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
-    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
-    pNewItem->colUsed = pOldItem->colUsed;
-  }
-  return pNew;
-}
-SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
-  IdList *pNew;
-  int i;
-  if( p==0 ) return 0;
-  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
-  if( pNew==0 ) return 0;
-  pNew->nId = pNew->nAlloc = p->nId;
-  pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
-  if( pNew->a==0 ){
-    sqlite3_free(pNew);
-    return 0;
-  }
-  for(i=0; i<p->nId; i++){
-    struct IdList_item *pNewItem = &pNew->a[i];
-    struct IdList_item *pOldItem = &p->a[i];
-    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
-    pNewItem->idx = pOldItem->idx;
-  }
-  return pNew;
-}
-SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p){
-  Select *pNew;
-  if( p==0 ) return 0;
-  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
-  if( pNew==0 ) return 0;
-  pNew->isDistinct = p->isDistinct;
-  pNew->pEList = sqlite3ExprListDup(db, p->pEList);
-  pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);
-  pNew->pWhere = sqlite3ExprDup(db, p->pWhere);
-  pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);
-  pNew->pHaving = sqlite3ExprDup(db, p->pHaving);
-  pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);
-  pNew->op = p->op;
-  pNew->pPrior = sqlite3SelectDup(db, p->pPrior);
-  pNew->pLimit = sqlite3ExprDup(db, p->pLimit);
-  pNew->pOffset = sqlite3ExprDup(db, p->pOffset);
-  pNew->iLimit = -1;
-  pNew->iOffset = -1;
-  pNew->isResolved = p->isResolved;
-  pNew->isAgg = p->isAgg;
-  pNew->usesEphm = 0;
-  pNew->disallowOrderBy = 0;
-  pNew->pRightmost = 0;
-  pNew->addrOpenEphm[0] = -1;
-  pNew->addrOpenEphm[1] = -1;
-  pNew->addrOpenEphm[2] = -1;
-  return pNew;
-}
-#else
-SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p){
-  assert( p==0 );
-  return 0;
-}
-#endif
+case OP_Variable: {
+#if 0  /* local variables moved into u.ab */
+  int p1;          /* Variable to copy from */
+  int p2;          /* Register to copy to */
+  int n;           /* Number of values left to copy */
+  Mem *pVar;       /* Value being transferred */
+#endif /* local variables moved into u.ab */
 
+  u.ab.p1 = pOp->p1 - 1;
+  u.ab.p2 = pOp->p2;
+  u.ab.n = pOp->p3;
+  assert( u.ab.p1>=0 && u.ab.p1+u.ab.n<=p->nVar );
+  assert( u.ab.p2>=1 && u.ab.p2+u.ab.n-1<=p->nMem );
+  assert( pOp->p4.z==0 || pOp->p3==1 );
 
-/*
-** Add a new element to the end of an expression list.  If pList is
-** initially NULL, then create a new expression list.
-*/
-SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(
-  Parse *pParse,          /* Parsing context */
-  ExprList *pList,        /* List to which to append. Might be NULL */
-  Expr *pExpr,            /* Expression to be appended */
-  Token *pName            /* AS keyword for the expression */
-){
-  sqlite3 *db = pParse->db;
-  if( pList==0 ){
-    pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
-    if( pList==0 ){
-      goto no_mem;
-    }
-    assert( pList->nAlloc==0 );
-  }
-  if( pList->nAlloc<=pList->nExpr ){
-    struct ExprList_item *a;
-    int n = pList->nAlloc*2 + 4;
-    a = sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));
-    if( a==0 ){
-      goto no_mem;
+  while( u.ab.n-- > 0 ){
+    u.ab.pVar = &p->aVar[u.ab.p1++];
+    if( sqlite3VdbeMemTooBig(u.ab.pVar) ){
+      goto too_big;
     }
-    pList->a = a;
-    pList->nAlloc = n;
-  }
-  assert( pList->a!=0 );
-  if( pExpr || pName ){
-    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
-    memset(pItem, 0, sizeof(*pItem));
-    pItem->zName = sqlite3NameFromToken(db, pName);
-    pItem->pExpr = pExpr;
-  }
-  return pList;
-
-no_mem:     
-  /* Avoid leaking memory if malloc has failed. */
-  sqlite3ExprDelete(pExpr);
-  sqlite3ExprListDelete(pList);
-  return 0;
-}
-
-/*
-** If the expression list pEList contains more than iLimit elements,
-** leave an error message in pParse.
-*/
-SQLITE_PRIVATE void sqlite3ExprListCheckLength(
-  Parse *pParse,
-  ExprList *pEList,
-  const char *zObject
-){
-  int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN];
-  testcase( pEList && pEList->nExpr==mx );
-  testcase( pEList && pEList->nExpr==mx+1 );
-  if( pEList && pEList->nExpr>mx ){
-    sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
+    pOut = &p->aMem[u.ab.p2++];
+    sqlite3VdbeMemReleaseExternal(pOut);
+    pOut->flags = MEM_Null;
+    sqlite3VdbeMemShallowCopy(pOut, u.ab.pVar, MEM_Static);
+    UPDATE_MAX_BLOBSIZE(pOut);
   }
+  break;
 }
 
-
-/* The following three functions, heightOfExpr(), heightOfExprList()
-** and heightOfSelect(), are used to determine the maximum height
-** of any expression tree referenced by the structure passed as the
-** first argument.
+/* Opcode: Move P1 P2 P3 * *
 **
-** If this maximum height is greater than the current value pointed
-** to by pnHeight, the second parameter, then set *pnHeight to that
-** value.
+** Move the values in register P1..P1+P3-1 over into
+** registers P2..P2+P3-1.  Registers P1..P1+P1-1 are
+** left holding a NULL.  It is an error for register ranges
+** P1..P1+P3-1 and P2..P2+P3-1 to overlap.
 */
-static void heightOfExpr(Expr *p, int *pnHeight){
-  if( p ){
-    if( p->nHeight>*pnHeight ){
-      *pnHeight = p->nHeight;
-    }
-  }
-}
-static void heightOfExprList(ExprList *p, int *pnHeight){
-  if( p ){
-    int i;
-    for(i=0; i<p->nExpr; i++){
-      heightOfExpr(p->a[i].pExpr, pnHeight);
-    }
-  }
-}
-static void heightOfSelect(Select *p, int *pnHeight){
-  if( p ){
-    heightOfExpr(p->pWhere, pnHeight);
-    heightOfExpr(p->pHaving, pnHeight);
-    heightOfExpr(p->pLimit, pnHeight);
-    heightOfExpr(p->pOffset, pnHeight);
-    heightOfExprList(p->pEList, pnHeight);
-    heightOfExprList(p->pGroupBy, pnHeight);
-    heightOfExprList(p->pOrderBy, pnHeight);
-    heightOfSelect(p->pPrior, pnHeight);
+case OP_Move: {
+#if 0  /* local variables moved into u.ac */
+  char *zMalloc;   /* Holding variable for allocated memory */
+  int n;           /* Number of registers left to copy */
+  int p1;          /* Register to copy from */
+  int p2;          /* Register to copy to */
+#endif /* local variables moved into u.ac */
+
+  u.ac.n = pOp->p3;
+  u.ac.p1 = pOp->p1;
+  u.ac.p2 = pOp->p2;
+  assert( u.ac.n>0 && u.ac.p1>0 && u.ac.p2>0 );
+  assert( u.ac.p1+u.ac.n<=u.ac.p2 || u.ac.p2+u.ac.n<=u.ac.p1 );
+
+  pIn1 = &p->aMem[u.ac.p1];
+  pOut = &p->aMem[u.ac.p2];
+  while( u.ac.n-- ){
+    assert( pOut<=&p->aMem[p->nMem] );
+    assert( pIn1<=&p->aMem[p->nMem] );
+    u.ac.zMalloc = pOut->zMalloc;
+    pOut->zMalloc = 0;
+    sqlite3VdbeMemMove(pOut, pIn1);
+    pIn1->zMalloc = u.ac.zMalloc;
+    REGISTER_TRACE(u.ac.p2++, pOut);
+    pIn1++;
+    pOut++;
   }
+  break;
 }
 
-/*
-** Set the Expr.nHeight variable in the structure passed as an 
-** argument. An expression with no children, Expr.pList or 
-** Expr.pSelect member has a height of 1. Any other expression
-** has a height equal to the maximum height of any other 
-** referenced Expr plus one.
+/* Opcode: Copy P1 P2 * * *
+**
+** Make a copy of register P1 into register P2.
+**
+** This instruction makes a deep copy of the value.  A duplicate
+** is made of any string or blob constant.  See also OP_SCopy.
 */
-SQLITE_PRIVATE void sqlite3ExprSetHeight(Expr *p){
-  int nHeight = 0;
-  heightOfExpr(p->pLeft, &nHeight);
-  heightOfExpr(p->pRight, &nHeight);
-  heightOfExprList(p->pList, &nHeight);
-  heightOfSelect(p->pSelect, &nHeight);
-  p->nHeight = nHeight + 1;
+case OP_Copy: {             /* in1 */
+  assert( pOp->p2>0 );
+  assert( pOp->p2<=p->nMem );
+  pOut = &p->aMem[pOp->p2];
+  assert( pOut!=pIn1 );
+  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+  Deephemeralize(pOut);
+  REGISTER_TRACE(pOp->p2, pOut);
+  break;
 }
 
-/*
-** Return the maximum height of any expression tree referenced
-** by the select statement passed as an argument.
+/* Opcode: SCopy P1 P2 * * *
+**
+** Make a shallow copy of register P1 into register P2.
+**
+** This instruction makes a shallow copy of the value.  If the value
+** is a string or blob, then the copy is only a pointer to the
+** original and hence if the original changes so will the copy.
+** Worse, if the original is deallocated, the copy becomes invalid.
+** Thus the program must guarantee that the original will not change
+** during the lifetime of the copy.  Use OP_Copy to make a complete
+** copy.
 */
-SQLITE_PRIVATE int sqlite3SelectExprHeight(Select *p){
-  int nHeight = 0;
-  heightOfSelect(p, &nHeight);
-  return nHeight;
+case OP_SCopy: {            /* in1 */
+  REGISTER_TRACE(pOp->p1, pIn1);
+  assert( pOp->p2>0 );
+  assert( pOp->p2<=p->nMem );
+  pOut = &p->aMem[pOp->p2];
+  assert( pOut!=pIn1 );
+  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+  REGISTER_TRACE(pOp->p2, pOut);
+  break;
 }
 
-/*
-** Delete an entire expression list.
+/* Opcode: ResultRow P1 P2 * * *
+**
+** The registers P1 through P1+P2-1 contain a single row of
+** results. This opcode causes the sqlite3_step() call to terminate
+** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
+** structure to provide access to the top P1 values as the result
+** row.
 */
-SQLITE_PRIVATE void sqlite3ExprListDelete(ExprList *pList){
+case OP_ResultRow: {
+#if 0  /* local variables moved into u.ad */
+  Mem *pMem;
   int i;
-  struct ExprList_item *pItem;
-  if( pList==0 ) return;
-  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
-  assert( pList->nExpr<=pList->nAlloc );
-  for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
-    sqlite3ExprDelete(pItem->pExpr);
-    sqlite3_free(pItem->zName);
+#endif /* local variables moved into u.ad */
+  assert( p->nResColumn==pOp->p2 );
+  assert( pOp->p1>0 );
+  assert( pOp->p1+pOp->p2<=p->nMem+1 );
+
+  /* If this statement has violated immediate foreign key constraints, do
+  ** not return the number of rows modified. And do not RELEASE the statement
+  ** transaction. It needs to be rolled back.  */
+  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
+    assert( db->flags&SQLITE_CountRows );
+    assert( p->usesStmtJournal );
+    break;
   }
-  sqlite3_free(pList->a);
-  sqlite3_free(pList);
-}
 
-/*
-** Walk an expression tree.  Call xFunc for each node visited.  xFunc
-** is called on the node before xFunc is called on the nodes children.
-**
-** The return value from xFunc determines whether the tree walk continues.
-** 0 means continue walking the tree.  1 means do not walk children
-** of the current node but continue with siblings.  2 means abandon
-** the tree walk completely.
-**
-** The return value from this routine is 1 to abandon the tree walk
-** and 0 to continue.
-**
-** NOTICE:  This routine does *not* descend into subqueries.
-*/
-static int walkExprList(ExprList *, int (*)(void *, Expr*), void *);
-static int walkExprTree(Expr *pExpr, int (*xFunc)(void*,Expr*), void *pArg){
-  int rc;
-  if( pExpr==0 ) return 0;
-  rc = (*xFunc)(pArg, pExpr);
-  if( rc==0 ){
-    if( walkExprTree(pExpr->pLeft, xFunc, pArg) ) return 1;
-    if( walkExprTree(pExpr->pRight, xFunc, pArg) ) return 1;
-    if( walkExprList(pExpr->pList, xFunc, pArg) ) return 1;
+  /* If the SQLITE_CountRows flag is set in sqlite3.flags mask, then
+  ** DML statements invoke this opcode to return the number of rows
+  ** modified to the user. This is the only way that a VM that
+  ** opens a statement transaction may invoke this opcode.
+  **
+  ** In case this is such a statement, close any statement transaction
+  ** opened by this VM before returning control to the user. This is to
+  ** ensure that statement-transactions are always nested, not overlapping.
+  ** If the open statement-transaction is not closed here, then the user
+  ** may step another VM that opens its own statement transaction. This
+  ** may lead to overlapping statement transactions.
+  **
+  ** The statement transaction is never a top-level transaction.  Hence
+  ** the RELEASE call below can never fail.
+  */
+  assert( p->iStatement==0 || db->flags&SQLITE_CountRows );
+  rc = sqlite3VdbeCloseStatement(p, SAVEPOINT_RELEASE);
+  if( NEVER(rc!=SQLITE_OK) ){
+    break;
   }
-  return rc>1;
-}
 
-/*
-** Call walkExprTree() for every expression in list p.
-*/
-static int walkExprList(ExprList *p, int (*xFunc)(void *, Expr*), void *pArg){
-  int i;
-  struct ExprList_item *pItem;
-  if( !p ) return 0;
-  for(i=p->nExpr, pItem=p->a; i>0; i--, pItem++){
-    if( walkExprTree(pItem->pExpr, xFunc, pArg) ) return 1;
-  }
-  return 0;
-}
+  /* Invalidate all ephemeral cursor row caches */
+  p->cacheCtr = (p->cacheCtr + 2)|1;
 
-/*
-** Call walkExprTree() for every expression in Select p, not including
-** expressions that are part of sub-selects in any FROM clause or the LIMIT
-** or OFFSET expressions..
-*/
-static int walkSelectExpr(Select *p, int (*xFunc)(void *, Expr*), void *pArg){
-  walkExprList(p->pEList, xFunc, pArg);
-  walkExprTree(p->pWhere, xFunc, pArg);
-  walkExprList(p->pGroupBy, xFunc, pArg);
-  walkExprTree(p->pHaving, xFunc, pArg);
-  walkExprList(p->pOrderBy, xFunc, pArg);
-  if( p->pPrior ){
-    walkSelectExpr(p->pPrior, xFunc, pArg);
+  /* Make sure the results of the current row are \000 terminated
+  ** and have an assigned type.  The results are de-ephemeralized as
+  ** as side effect.
+  */
+  u.ad.pMem = p->pResultSet = &p->aMem[pOp->p1];
+  for(u.ad.i=0; u.ad.i<pOp->p2; u.ad.i++){
+    sqlite3VdbeMemNulTerminate(&u.ad.pMem[u.ad.i]);
+    storeTypeInfo(&u.ad.pMem[u.ad.i], encoding);
+    REGISTER_TRACE(pOp->p1+u.ad.i, &u.ad.pMem[u.ad.i]);
   }
-  return 0;
-}
+  if( db->mallocFailed ) goto no_mem;
 
+  /* Return SQLITE_ROW
+  */
+  p->pc = pc + 1;
+  rc = SQLITE_ROW;
+  goto vdbe_return;
+}
 
-/*
-** This routine is designed as an xFunc for walkExprTree().
+/* Opcode: Concat P1 P2 P3 * *
+**
+** Add the text in register P1 onto the end of the text in
+** register P2 and store the result in register P3.
+** If either the P1 or P2 text are NULL then store NULL in P3.
 **
-** pArg is really a pointer to an integer.  If we can tell by looking
-** at pExpr that the expression that contains pExpr is not a constant
-** expression, then set *pArg to 0 and return 2 to abandon the tree walk.
-** If pExpr does does not disqualify the expression from being a constant
-** then do nothing.
+**   P3 = P2 || P1
 **
-** After walking the whole tree, if no nodes are found that disqualify
-** the expression as constant, then we assume the whole expression
-** is constant.  See sqlite3ExprIsConstant() for additional information.
+** It is illegal for P1 and P3 to be the same register. Sometimes,
+** if P3 is the same register as P2, the implementation is able
+** to avoid a memcpy().
 */
-static int exprNodeIsConstant(void *pArg, Expr *pExpr){
-  int *pN = (int*)pArg;
+case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
+#if 0  /* local variables moved into u.ae */
+  i64 nByte;
+#endif /* local variables moved into u.ae */
 
-  /* If *pArg is 3 then any term of the expression that comes from
-  ** the ON or USING clauses of a join disqualifies the expression
-  ** from being considered constant. */
-  if( (*pN)==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
-    *pN = 0;
-    return 2;
+  assert( pIn1!=pOut );
+  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
+    sqlite3VdbeMemSetNull(pOut);
+    break;
   }
-
-  switch( pExpr->op ){
-    /* Consider functions to be constant if all their arguments are constant
-    ** and *pArg==2 */
-    case TK_FUNCTION:
-      if( (*pN)==2 ) return 0;
-      /* Fall through */
-    case TK_ID:
-    case TK_COLUMN:
-    case TK_DOT:
-    case TK_AGG_FUNCTION:
-    case TK_AGG_COLUMN:
-#ifndef SQLITE_OMIT_SUBQUERY
-    case TK_SELECT:
-    case TK_EXISTS:
-      testcase( pExpr->op==TK_SELECT );
-      testcase( pExpr->op==TK_EXISTS );
-#endif
-      testcase( pExpr->op==TK_ID );
-      testcase( pExpr->op==TK_COLUMN );
-      testcase( pExpr->op==TK_DOT );
-      testcase( pExpr->op==TK_AGG_FUNCTION );
-      testcase( pExpr->op==TK_AGG_COLUMN );
-      *pN = 0;
-      return 2;
-    case TK_IN:
-      if( pExpr->pSelect ){
-        *pN = 0;
-        return 2;
-      }
-    default:
-      return 0;
+  if( ExpandBlob(pIn1) || ExpandBlob(pIn2) ) goto no_mem;
+  Stringify(pIn1, encoding);
+  Stringify(pIn2, encoding);
+  u.ae.nByte = pIn1->n + pIn2->n;
+  if( u.ae.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    goto too_big;
+  }
+  MemSetTypeFlag(pOut, MEM_Str);
+  if( sqlite3VdbeMemGrow(pOut, (int)u.ae.nByte+2, pOut==pIn2) ){
+    goto no_mem;
   }
+  if( pOut!=pIn2 ){
+    memcpy(pOut->z, pIn2->z, pIn2->n);
+  }
+  memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
+  pOut->z[u.ae.nByte] = 0;
+  pOut->z[u.ae.nByte+1] = 0;
+  pOut->flags |= MEM_Term;
+  pOut->n = (int)u.ae.nByte;
+  pOut->enc = encoding;
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
 }
 
-/*
-** Walk an expression tree.  Return 1 if the expression is constant
-** and 0 if it involves variables or function calls.
+/* Opcode: Add P1 P2 P3 * *
 **
-** For the purposes of this function, a double-quoted string (ex: "abc")
-** is considered a variable but a single-quoted string (ex: 'abc') is
-** a constant.
+** Add the value in register P1 to the value in register P2
+** and store the result in register P3.
+** If either input is NULL, the result is NULL.
 */
-SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr *p){
-  int isConst = 1;
-  walkExprTree(p, exprNodeIsConstant, &isConst);
-  return isConst;
-}
-
-/*
-** Walk an expression tree.  Return 1 if the expression is constant
-** that does no originate from the ON or USING clauses of a join.
-** Return 0 if it involves variables or function calls or terms from
-** an ON or USING clause.
+/* Opcode: Multiply P1 P2 P3 * *
+**
+**
+** Multiply the value in register P1 by the value in register P2
+** and store the result in register P3.
+** If either input is NULL, the result is NULL.
 */
-SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr *p){
-  int isConst = 3;
-  walkExprTree(p, exprNodeIsConstant, &isConst);
-  return isConst!=0;
-}
-
-/*
-** Walk an expression tree.  Return 1 if the expression is constant
-** or a function call with constant arguments.  Return and 0 if there
-** are any variables.
+/* Opcode: Subtract P1 P2 P3 * *
 **
-** For the purposes of this function, a double-quoted string (ex: "abc")
-** is considered a variable but a single-quoted string (ex: 'abc') is
-** a constant.
+** Subtract the value in register P1 from the value in register P2
+** and store the result in register P3.
+** If either input is NULL, the result is NULL.
 */
-SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr *p){
-  int isConst = 2;
-  walkExprTree(p, exprNodeIsConstant, &isConst);
-  return isConst!=0;
-}
-
-/*
-** If the expression p codes a constant integer that is small enough
-** to fit in a 32-bit integer, return 1 and put the value of the integer
-** in *pValue.  If the expression is not an integer or if it is too big
-** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
+/* Opcode: Divide P1 P2 P3 * *
+**
+** Divide the value in register P1 by the value in register P2
+** and store the result in register P3 (P3=P2/P1). If the value in 
+** register P1 is zero, then the result is NULL. If either input is 
+** NULL, the result is NULL.
 */
-SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr *p, int *pValue){
-  switch( p->op ){
-    case TK_INTEGER: {
-      if( sqlite3GetInt32((char*)p->token.z, pValue) ){
-        return 1;
+/* Opcode: Remainder P1 P2 P3 * *
+**
+** Compute the remainder after integer division of the value in
+** register P1 by the value in register P2 and store the result in P3. 
+** If the value in register P2 is zero the result is NULL.
+** If either operand is NULL, the result is NULL.
+*/
+case OP_Add:                   /* same as TK_PLUS, in1, in2, out3 */
+case OP_Subtract:              /* same as TK_MINUS, in1, in2, out3 */
+case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
+case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
+case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
+#if 0  /* local variables moved into u.af */
+  int flags;      /* Combined MEM_* flags from both inputs */
+  i64 iA;         /* Integer value of left operand */
+  i64 iB;         /* Integer value of right operand */
+  double rA;      /* Real value of left operand */
+  double rB;      /* Real value of right operand */
+#endif /* local variables moved into u.af */
+
+  applyNumericAffinity(pIn1);
+  applyNumericAffinity(pIn2);
+  u.af.flags = pIn1->flags | pIn2->flags;
+  if( (u.af.flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
+  if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
+    u.af.iA = pIn1->u.i;
+    u.af.iB = pIn2->u.i;
+    switch( pOp->opcode ){
+      case OP_Add:         u.af.iB += u.af.iA;       break;
+      case OP_Subtract:    u.af.iB -= u.af.iA;       break;
+      case OP_Multiply:    u.af.iB *= u.af.iA;       break;
+      case OP_Divide: {
+        if( u.af.iA==0 ) goto arithmetic_result_is_null;
+        /* Dividing the largest possible negative 64-bit integer (1<<63) by
+        ** -1 returns an integer too large to store in a 64-bit data-type. On
+        ** some architectures, the value overflows to (1<<63). On others,
+        ** a SIGFPE is issued. The following statement normalizes this
+        ** behavior so that all architectures behave as if integer
+        ** overflow occurred.
+        */
+        if( u.af.iA==-1 && u.af.iB==SMALLEST_INT64 ) u.af.iA = 1;
+        u.af.iB /= u.af.iA;
+        break;
+      }
+      default: {
+        if( u.af.iA==0 ) goto arithmetic_result_is_null;
+        if( u.af.iA==-1 ) u.af.iA = 1;
+        u.af.iB %= u.af.iA;
+        break;
       }
-      break;
-    }
-    case TK_UPLUS: {
-      return sqlite3ExprIsInteger(p->pLeft, pValue);
     }
-    case TK_UMINUS: {
-      int v;
-      if( sqlite3ExprIsInteger(p->pLeft, &v) ){
-        *pValue = -v;
-        return 1;
+    pOut->u.i = u.af.iB;
+    MemSetTypeFlag(pOut, MEM_Int);
+  }else{
+    u.af.rA = sqlite3VdbeRealValue(pIn1);
+    u.af.rB = sqlite3VdbeRealValue(pIn2);
+    switch( pOp->opcode ){
+      case OP_Add:         u.af.rB += u.af.rA;       break;
+      case OP_Subtract:    u.af.rB -= u.af.rA;       break;
+      case OP_Multiply:    u.af.rB *= u.af.rA;       break;
+      case OP_Divide: {
+        /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+        if( u.af.rA==(double)0 ) goto arithmetic_result_is_null;
+        u.af.rB /= u.af.rA;
+        break;
+      }
+      default: {
+        u.af.iA = (i64)u.af.rA;
+        u.af.iB = (i64)u.af.rB;
+        if( u.af.iA==0 ) goto arithmetic_result_is_null;
+        if( u.af.iA==-1 ) u.af.iA = 1;
+        u.af.rB = (double)(u.af.iB % u.af.iA);
+        break;
       }
-      break;
     }
-    default: break;
+    if( sqlite3IsNaN(u.af.rB) ){
+      goto arithmetic_result_is_null;
+    }
+    pOut->r = u.af.rB;
+    MemSetTypeFlag(pOut, MEM_Real);
+    if( (u.af.flags & MEM_Real)==0 ){
+      sqlite3VdbeIntegerAffinity(pOut);
+    }
   }
-  return 0;
+  break;
+
+arithmetic_result_is_null:
+  sqlite3VdbeMemSetNull(pOut);
+  break;
 }
 
-/*
-** Return TRUE if the given string is a row-id column name.
+/* Opcode: CollSeq * * P4
+**
+** P4 is a pointer to a CollSeq struct. If the next call to a user function
+** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will
+** be returned. This is used by the built-in min(), max() and nullif()
+** functions.
+**
+** The interface used by the implementation of the aforementioned functions
+** to retrieve the collation sequence set by this opcode is not available
+** publicly, only to user functions defined in func.c.
 */
-SQLITE_PRIVATE int sqlite3IsRowid(const char *z){
-  if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
-  if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
-  if( sqlite3StrICmp(z, "OID")==0 ) return 1;
-  return 0;
+case OP_CollSeq: {
+  assert( pOp->p4type==P4_COLLSEQ );
+  break;
 }
 
-/*
-** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
-** that name in the set of source tables in pSrcList and make the pExpr 
-** expression node refer back to that source column.  The following changes
-** are made to pExpr:
+/* Opcode: Function P1 P2 P3 P4 P5
 **
-**    pExpr->iDb           Set the index in db->aDb[] of the database holding
-**                         the table.
-**    pExpr->iTable        Set to the cursor number for the table obtained
-**                         from pSrcList.
-**    pExpr->iColumn       Set to the column number within the table.
-**    pExpr->op            Set to TK_COLUMN.
-**    pExpr->pLeft         Any expression this points to is deleted
-**    pExpr->pRight        Any expression this points to is deleted.
+** Invoke a user function (P4 is a pointer to a Function structure that
+** defines the function) with P5 arguments taken from register P2 and
+** successors.  The result of the function is stored in register P3.
+** Register P3 must not be one of the function inputs.
 **
-** The pDbToken is the name of the database (the "X").  This value may be
-** NULL meaning that name is of the form Y.Z or Z.  Any available database
-** can be used.  The pTableToken is the name of the table (the "Y").  This
-** value can be NULL if pDbToken is also NULL.  If pTableToken is NULL it
-** means that the form of the name is Z and that columns from any table
-** can be used.
+** P1 is a 32-bit bitmask indicating whether or not each argument to the 
+** function was determined to be constant at compile time. If the first
+** argument was constant then bit 0 of P1 is set. This is used to determine
+** whether meta data associated with a user function argument using the
+** sqlite3_set_auxdata() API may be safely retained until the next
+** invocation of this opcode.
 **
-** If the name cannot be resolved unambiguously, leave an error message
-** in pParse and return non-zero.  Return zero on success.
+** See also: AggStep and AggFinal
 */
-static int lookupName(
-  Parse *pParse,       /* The parsing context */
-  Token *pDbToken,     /* Name of the database containing table, or NULL */
-  Token *pTableToken,  /* Name of table containing column, or NULL */
-  Token *pColumnToken, /* Name of the column. */
-  NameContext *pNC,    /* The name context used to resolve the name */
-  Expr *pExpr          /* Make this EXPR node point to the selected column */
-){
-  char *zDb = 0;       /* Name of the database.  The "X" in X.Y.Z */
-  char *zTab = 0;      /* Name of the table.  The "Y" in X.Y.Z or Y.Z */
-  char *zCol = 0;      /* Name of the column.  The "Z" */
-  int i, j;            /* Loop counters */
-  int cnt = 0;         /* Number of matching column names */
-  int cntTab = 0;      /* Number of matching table names */
-  sqlite3 *db = pParse->db;  /* The database */
-  struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
-  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
-  NameContext *pTopNC = pNC;        /* First namecontext in the list */
-  Schema *pSchema = 0;              /* Schema of the expression */
-
-  assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
-  zDb = sqlite3NameFromToken(db, pDbToken);
-  zTab = sqlite3NameFromToken(db, pTableToken);
-  zCol = sqlite3NameFromToken(db, pColumnToken);
-  if( db->mallocFailed ){
-    goto lookupname_end;
-  }
-
-  pExpr->iTable = -1;
-  while( pNC && cnt==0 ){
-    ExprList *pEList;
-    SrcList *pSrcList = pNC->pSrcList;
+case OP_Function: {
+#if 0  /* local variables moved into u.ag */
+  int i;
+  Mem *pArg;
+  sqlite3_context ctx;
+  sqlite3_value **apVal;
+  int n;
+#endif /* local variables moved into u.ag */
 
-    if( pSrcList ){
-      for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
-        Table *pTab;
-        int iDb;
-        Column *pCol;
-  
-        pTab = pItem->pTab;
-        assert( pTab!=0 );
-        iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-        assert( pTab->nCol>0 );
-        if( zTab ){
-          if( pItem->zAlias ){
-            char *zTabName = pItem->zAlias;
-            if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
-          }else{
-            char *zTabName = pTab->zName;
-            if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
-            if( zDb!=0 && sqlite3StrICmp(db->aDb[iDb].zName, zDb)!=0 ){
-              continue;
-            }
-          }
-        }
-        if( 0==(cntTab++) ){
-          pExpr->iTable = pItem->iCursor;
-          pSchema = pTab->pSchema;
-          pMatch = pItem;
-        }
-        for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
-          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
-            const char *zColl = pTab->aCol[j].zColl;
-            IdList *pUsing;
-            cnt++;
-            pExpr->iTable = pItem->iCursor;
-            pMatch = pItem;
-            pSchema = pTab->pSchema;
-            /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
-            pExpr->iColumn = j==pTab->iPKey ? -1 : j;
-            pExpr->affinity = pTab->aCol[j].affinity;
-            if( (pExpr->flags & EP_ExpCollate)==0 ){
-              pExpr->pColl = sqlite3FindCollSeq(db, ENC(db), zColl,-1, 0);
-            }
-            if( i<pSrcList->nSrc-1 ){
-              if( pItem[1].jointype & JT_NATURAL ){
-                /* If this match occurred in the left table of a natural join,
-                ** then skip the right table to avoid a duplicate match */
-                pItem++;
-                i++;
-              }else if( (pUsing = pItem[1].pUsing)!=0 ){
-                /* If this match occurs on a column that is in the USING clause
-                ** of a join, skip the search of the right table of the join
-                ** to avoid a duplicate match there. */
-                int k;
-                for(k=0; k<pUsing->nId; k++){
-                  if( sqlite3StrICmp(pUsing->a[k].zName, zCol)==0 ){
-                    pItem++;
-                    i++;
-                    break;
-                  }
-                }
-              }
-            }
-            break;
-          }
-        }
-      }
-    }
+  u.ag.n = pOp->p5;
+  u.ag.apVal = p->apArg;
+  assert( u.ag.apVal || u.ag.n==0 );
 
-#ifndef SQLITE_OMIT_TRIGGER
-    /* If we have not already resolved the name, then maybe 
-    ** it is a new.* or old.* trigger argument reference
-    */
-    if( zDb==0 && zTab!=0 && cnt==0 && pParse->trigStack!=0 ){
-      TriggerStack *pTriggerStack = pParse->trigStack;
-      Table *pTab = 0;
-      u32 *piColMask;
-      if( pTriggerStack->newIdx != -1 && sqlite3StrICmp("new", zTab) == 0 ){
-        pExpr->iTable = pTriggerStack->newIdx;
-        assert( pTriggerStack->pTab );
-        pTab = pTriggerStack->pTab;
-        piColMask = &(pTriggerStack->newColMask);
-      }else if( pTriggerStack->oldIdx != -1 && sqlite3StrICmp("old", zTab)==0 ){
-        pExpr->iTable = pTriggerStack->oldIdx;
-        assert( pTriggerStack->pTab );
-        pTab = pTriggerStack->pTab;
-        piColMask = &(pTriggerStack->oldColMask);
-      }
+  assert( u.ag.n==0 || (pOp->p2>0 && pOp->p2+u.ag.n<=p->nMem+1) );
+  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ag.n );
+  u.ag.pArg = &p->aMem[pOp->p2];
+  for(u.ag.i=0; u.ag.i<u.ag.n; u.ag.i++, u.ag.pArg++){
+    u.ag.apVal[u.ag.i] = u.ag.pArg;
+    storeTypeInfo(u.ag.pArg, encoding);
+    REGISTER_TRACE(pOp->p2, u.ag.pArg);
+  }
 
-      if( pTab ){ 
-        int iCol;
-        Column *pCol = pTab->aCol;
+  assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
+  if( pOp->p4type==P4_FUNCDEF ){
+    u.ag.ctx.pFunc = pOp->p4.pFunc;
+    u.ag.ctx.pVdbeFunc = 0;
+  }else{
+    u.ag.ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
+    u.ag.ctx.pFunc = u.ag.ctx.pVdbeFunc->pFunc;
+  }
 
-        pSchema = pTab->pSchema;
-        cntTab++;
-        for(iCol=0; iCol < pTab->nCol; iCol++, pCol++) {
-          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
-            const char *zColl = pTab->aCol[iCol].zColl;
-            cnt++;
-            pExpr->iColumn = iCol==pTab->iPKey ? -1 : iCol;
-            pExpr->affinity = pTab->aCol[iCol].affinity;
-            if( (pExpr->flags & EP_ExpCollate)==0 ){
-              pExpr->pColl = sqlite3FindCollSeq(db, ENC(db), zColl,-1, 0);
-            }
-            pExpr->pTab = pTab;
-            if( iCol>=0 ){
-              testcase( iCol==31 );
-              testcase( iCol==32 );
-              *piColMask |= ((u32)1<<iCol) | (iCol>=32?0xffffffff:0);
-            }
-            break;
-          }
-        }
-      }
-    }
-#endif /* !defined(SQLITE_OMIT_TRIGGER) */
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  pOut = &p->aMem[pOp->p3];
+  u.ag.ctx.s.flags = MEM_Null;
+  u.ag.ctx.s.db = db;
+  u.ag.ctx.s.xDel = 0;
+  u.ag.ctx.s.zMalloc = 0;
 
-    /*
-    ** Perhaps the name is a reference to the ROWID
-    */
-    if( cnt==0 && cntTab==1 && sqlite3IsRowid(zCol) ){
-      cnt = 1;
-      pExpr->iColumn = -1;
-      pExpr->affinity = SQLITE_AFF_INTEGER;
-    }
+  /* The output cell may already have a buffer allocated. Move
+  ** the pointer to u.ag.ctx.s so in case the user-function can use
+  ** the already allocated buffer instead of allocating a new one.
+  */
+  sqlite3VdbeMemMove(&u.ag.ctx.s, pOut);
+  MemSetTypeFlag(&u.ag.ctx.s, MEM_Null);
 
-    /*
-    ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z
-    ** might refer to an result-set alias.  This happens, for example, when
-    ** we are resolving names in the WHERE clause of the following command:
-    **
-    **     SELECT a+b AS x FROM table WHERE x<10;
+  u.ag.ctx.isError = 0;
+  if( u.ag.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
+    assert( pOp>p->aOp );
+    assert( pOp[-1].p4type==P4_COLLSEQ );
+    assert( pOp[-1].opcode==OP_CollSeq );
+    u.ag.ctx.pColl = pOp[-1].p4.pColl;
+  }
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+  (*u.ag.ctx.pFunc->xFunc)(&u.ag.ctx, u.ag.n, u.ag.apVal);
+  if( sqlite3SafetyOn(db) ){
+    sqlite3VdbeMemRelease(&u.ag.ctx.s);
+    goto abort_due_to_misuse;
+  }
+  if( db->mallocFailed ){
+    /* Even though a malloc() has failed, the implementation of the
+    ** user function may have called an sqlite3_result_XXX() function
+    ** to return a value. The following call releases any resources
+    ** associated with such a value.
     **
-    ** In cases like this, replace pExpr with a copy of the expression that
-    ** forms the result set entry ("a+b" in the example) and return immediately.
-    ** Note that the expression in the result set should have already been
-    ** resolved by the time the WHERE clause is resolved.
-    */
-    if( cnt==0 && (pEList = pNC->pEList)!=0 && zTab==0 ){
-      for(j=0; j<pEList->nExpr; j++){
-        char *zAs = pEList->a[j].zName;
-        if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
-          Expr *pDup, *pOrig;
-          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
-          assert( pExpr->pList==0 );
-          assert( pExpr->pSelect==0 );
-          pOrig = pEList->a[j].pExpr;
-          if( !pNC->allowAgg && ExprHasProperty(pOrig, EP_Agg) ){
-            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
-            sqlite3_free(zCol);
-            return 2;
-          }
-          pDup = sqlite3ExprDup(db, pOrig);
-          if( pExpr->flags & EP_ExpCollate ){
-            pDup->pColl = pExpr->pColl;
-            pDup->flags |= EP_ExpCollate;
-          }
-          if( pExpr->span.dyn ) sqlite3_free((char*)pExpr->span.z);
-          if( pExpr->token.dyn ) sqlite3_free((char*)pExpr->token.z);
-          memcpy(pExpr, pDup, sizeof(*pExpr));
-          sqlite3_free(pDup);
-          cnt = 1;
-          pMatch = 0;
-          assert( zTab==0 && zDb==0 );
-          goto lookupname_end_2;
-        }
-      } 
-    }
-
-    /* Advance to the next name context.  The loop will exit when either
-    ** we have a match (cnt>0) or when we run out of name contexts.
+    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
+    ** fails also (the if(...) statement above). But if people are
+    ** misusing sqlite, they have bigger problems than a leaked value.
     */
-    if( cnt==0 ){
-      pNC = pNC->pNext;
-    }
+    sqlite3VdbeMemRelease(&u.ag.ctx.s);
+    goto no_mem;
   }
 
-  /*
-  ** If X and Y are NULL (in other words if only the column name Z is
-  ** supplied) and the value of Z is enclosed in double-quotes, then
-  ** Z is a string literal if it doesn't match any column names.  In that
-  ** case, we need to return right away and not make any changes to
-  ** pExpr.
-  **
-  ** Because no reference was made to outer contexts, the pNC->nRef
-  ** fields are not changed in any context.
+  /* If any auxiliary data functions have been called by this user function,
+  ** immediately call the destructor for any non-static values.
   */
-  if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){
-    sqlite3_free(zCol);
-    return 0;
+  if( u.ag.ctx.pVdbeFunc ){
+    sqlite3VdbeDeleteAuxData(u.ag.ctx.pVdbeFunc, pOp->p1);
+    pOp->p4.pVdbeFunc = u.ag.ctx.pVdbeFunc;
+    pOp->p4type = P4_VDBEFUNC;
   }
 
-  /*
-  ** cnt==0 means there was not match.  cnt>1 means there were two or
-  ** more matches.  Either way, we have an error.
-  */
-  if( cnt!=1 ){
-    const char *zErr;
-    zErr = cnt==0 ? "no such column" : "ambiguous column name";
-    if( zDb ){
-      sqlite3ErrorMsg(pParse, "%s: %s.%s.%s", zErr, zDb, zTab, zCol);
-    }else if( zTab ){
-      sqlite3ErrorMsg(pParse, "%s: %s.%s", zErr, zTab, zCol);
-    }else{
-      sqlite3ErrorMsg(pParse, "%s: %s", zErr, zCol);
-    }
-    pTopNC->nErr++;
+  /* If the function returned an error, throw an exception */
+  if( u.ag.ctx.isError ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.ag.ctx.s));
+    rc = u.ag.ctx.isError;
   }
 
-  /* If a column from a table in pSrcList is referenced, then record
-  ** this fact in the pSrcList.a[].colUsed bitmask.  Column 0 causes
-  ** bit 0 to be set.  Column 1 sets bit 1.  And so forth.  If the
-  ** column number is greater than the number of bits in the bitmask
-  ** then set the high-order bit of the bitmask.
-  */
-  if( pExpr->iColumn>=0 && pMatch!=0 ){
-    int n = pExpr->iColumn;
-    testcase( n==sizeof(Bitmask)*8-1 );
-    if( n>=sizeof(Bitmask)*8 ){
-      n = sizeof(Bitmask)*8-1;
-    }
-    assert( pMatch->iCursor==pExpr->iTable );
-    pMatch->colUsed |= ((Bitmask)1)<<n;
+  /* Copy the result of the function into register P3 */
+  sqlite3VdbeChangeEncoding(&u.ag.ctx.s, encoding);
+  sqlite3VdbeMemMove(pOut, &u.ag.ctx.s);
+  if( sqlite3VdbeMemTooBig(pOut) ){
+    goto too_big;
   }
+  REGISTER_TRACE(pOp->p3, pOut);
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
+}
 
-lookupname_end:
-  /* Clean up and return
-  */
-  sqlite3_free(zDb);
-  sqlite3_free(zTab);
-  sqlite3ExprDelete(pExpr->pLeft);
-  pExpr->pLeft = 0;
-  sqlite3ExprDelete(pExpr->pRight);
-  pExpr->pRight = 0;
-  pExpr->op = TK_COLUMN;
-lookupname_end_2:
-  sqlite3_free(zCol);
-  if( cnt==1 ){
-    assert( pNC!=0 );
-    sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
-    if( pMatch && !pMatch->pSelect ){
-      pExpr->pTab = pMatch->pTab;
-    }
-    /* Increment the nRef value on all name contexts from TopNC up to
-    ** the point where the name matched. */
-    for(;;){
-      assert( pTopNC!=0 );
-      pTopNC->nRef++;
-      if( pTopNC==pNC ) break;
-      pTopNC = pTopNC->pNext;
+/* Opcode: BitAnd P1 P2 P3 * *
+**
+** Take the bit-wise AND of the values in register P1 and P2 and
+** store the result in register P3.
+** If either input is NULL, the result is NULL.
+*/
+/* Opcode: BitOr P1 P2 P3 * *
+**
+** Take the bit-wise OR of the values in register P1 and P2 and
+** store the result in register P3.
+** If either input is NULL, the result is NULL.
+*/
+/* Opcode: ShiftLeft P1 P2 P3 * *
+**
+** Shift the integer value in register P2 to the left by the
+** number of bits specified by the integer in regiser P1.
+** Store the result in register P3.
+** If either input is NULL, the result is NULL.
+*/
+/* Opcode: ShiftRight P1 P2 P3 * *
+**
+** Shift the integer value in register P2 to the right by the
+** number of bits specified by the integer in register P1.
+** Store the result in register P3.
+** If either input is NULL, the result is NULL.
+*/
+case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */
+case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
+case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
+case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
+#if 0  /* local variables moved into u.ah */
+  i64 a;
+  i64 b;
+#endif /* local variables moved into u.ah */
+
+  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
+    sqlite3VdbeMemSetNull(pOut);
+    break;
+  }
+  u.ah.a = sqlite3VdbeIntValue(pIn2);
+  u.ah.b = sqlite3VdbeIntValue(pIn1);
+  switch( pOp->opcode ){
+    case OP_BitAnd:      u.ah.a &= u.ah.b;     break;
+    case OP_BitOr:       u.ah.a |= u.ah.b;     break;
+    case OP_ShiftLeft:   u.ah.a <<= u.ah.b;    break;
+    default:  assert( pOp->opcode==OP_ShiftRight );
+                         u.ah.a >>= u.ah.b;    break;
+  }
+  pOut->u.i = u.ah.a;
+  MemSetTypeFlag(pOut, MEM_Int);
+  break;
+}
+
+/* Opcode: AddImm  P1 P2 * * *
+** 
+** Add the constant P2 to the value in register P1.
+** The result is always an integer.
+**
+** To force any register to be an integer, just add 0.
+*/
+case OP_AddImm: {            /* in1 */
+  sqlite3VdbeMemIntegerify(pIn1);
+  pIn1->u.i += pOp->p2;
+  break;
+}
+
+/* Opcode: MustBeInt P1 P2 * * *
+** 
+** Force the value in register P1 to be an integer.  If the value
+** in P1 is not an integer and cannot be converted into an integer
+** without data loss, then jump immediately to P2, or if P2==0
+** raise an SQLITE_MISMATCH exception.
+*/
+case OP_MustBeInt: {            /* jump, in1 */
+  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
+  if( (pIn1->flags & MEM_Int)==0 ){
+    if( pOp->p2==0 ){
+      rc = SQLITE_MISMATCH;
+      goto abort_due_to_error;
+    }else{
+      pc = pOp->p2 - 1;
     }
-    return 0;
-  } else {
-    return 1;
+  }else{
+    MemSetTypeFlag(pIn1, MEM_Int);
   }
+  break;
 }
 
-/*
-** This routine is designed as an xFunc for walkExprTree().
+/* Opcode: RealAffinity P1 * * * *
 **
-** Resolve symbolic names into TK_COLUMN operators for the current
-** node in the expression tree.  Return 0 to continue the search down
-** the tree or 2 to abort the tree walk.
+** If register P1 holds an integer convert it to a real value.
 **
-** This routine also does error checking and name resolution for
-** function names.  The operator for aggregate functions is changed
-** to TK_AGG_FUNCTION.
+** This opcode is used when extracting information from a column that
+** has REAL affinity.  Such column values may still be stored as
+** integers, for space efficiency, but after extraction we want them
+** to have only a real value.
 */
-static int nameResolverStep(void *pArg, Expr *pExpr){
-  NameContext *pNC = (NameContext*)pArg;
-  Parse *pParse;
+case OP_RealAffinity: {                  /* in1 */
+  if( pIn1->flags & MEM_Int ){
+    sqlite3VdbeMemRealify(pIn1);
+  }
+  break;
+}
 
-  if( pExpr==0 ) return 1;
-  assert( pNC!=0 );
-  pParse = pNC->pParse;
+#ifndef SQLITE_OMIT_CAST
+/* Opcode: ToText P1 * * * *
+**
+** Force the value in register P1 to be text.
+** If the value is numeric, convert it to a string using the
+** equivalent of printf().  Blob values are unchanged and
+** are afterwards simply interpreted as text.
+**
+** A NULL value is not changed by this routine.  It remains NULL.
+*/
+case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
+  if( pIn1->flags & MEM_Null ) break;
+  assert( MEM_Str==(MEM_Blob>>3) );
+  pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
+  applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
+  rc = ExpandBlob(pIn1);
+  assert( pIn1->flags & MEM_Str || db->mallocFailed );
+  pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero);
+  UPDATE_MAX_BLOBSIZE(pIn1);
+  break;
+}
 
-  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1;
-  ExprSetProperty(pExpr, EP_Resolved);
-#ifndef NDEBUG
-  if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){
-    SrcList *pSrcList = pNC->pSrcList;
-    int i;
-    for(i=0; i<pNC->pSrcList->nSrc; i++){
-      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
-    }
+/* Opcode: ToBlob P1 * * * *
+**
+** Force the value in register P1 to be a BLOB.
+** If the value is numeric, convert it to a string first.
+** Strings are simply reinterpreted as blobs with no change
+** to the underlying data.
+**
+** A NULL value is not changed by this routine.  It remains NULL.
+*/
+case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
+  if( pIn1->flags & MEM_Null ) break;
+  if( (pIn1->flags & MEM_Blob)==0 ){
+    applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
+    assert( pIn1->flags & MEM_Str || db->mallocFailed );
+    MemSetTypeFlag(pIn1, MEM_Blob);
+  }else{
+    pIn1->flags &= ~(MEM_TypeMask&~MEM_Blob);
   }
-#endif
-  switch( pExpr->op ){
-    /* Double-quoted strings (ex: "abc") are used as identifiers if
-    ** possible.  Otherwise they remain as strings.  Single-quoted
-    ** strings (ex: 'abc') are always string literals.
-    */
-    case TK_STRING: {
-      if( pExpr->token.z[0]=='\'' ) break;
-      /* Fall thru into the TK_ID case if this is a double-quoted string */
-    }
-    /* A lone identifier is the name of a column.
-    */
-    case TK_ID: {
-      lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);
-      return 1;
-    }
-  
-    /* A table name and column name:     ID.ID
-    ** Or a database, table and column:  ID.ID.ID
-    */
-    case TK_DOT: {
-      Token *pColumn;
-      Token *pTable;
-      Token *pDb;
-      Expr *pRight;
+  UPDATE_MAX_BLOBSIZE(pIn1);
+  break;
+}
 
-      /* if( pSrcList==0 ) break; */
-      pRight = pExpr->pRight;
-      if( pRight->op==TK_ID ){
-        pDb = 0;
-        pTable = &pExpr->pLeft->token;
-        pColumn = &pRight->token;
-      }else{
-        assert( pRight->op==TK_DOT );
-        pDb = &pExpr->pLeft->token;
-        pTable = &pRight->pLeft->token;
-        pColumn = &pRight->pRight->token;
-      }
-      lookupName(pParse, pDb, pTable, pColumn, pNC, pExpr);
-      return 1;
-    }
+/* Opcode: ToNumeric P1 * * * *
+**
+** Force the value in register P1 to be numeric (either an
+** integer or a floating-point number.)
+** If the value is text or blob, try to convert it to an using the
+** equivalent of atoi() or atof() and store 0 if no such conversion 
+** is possible.
+**
+** A NULL value is not changed by this routine.  It remains NULL.
+*/
+case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
+  if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
+    sqlite3VdbeMemNumerify(pIn1);
+  }
+  break;
+}
+#endif /* SQLITE_OMIT_CAST */
 
-    /* Resolve function names
-    */
-    case TK_CONST_FUNC:
-    case TK_FUNCTION: {
-      ExprList *pList = pExpr->pList;    /* The argument list */
-      int n = pList ? pList->nExpr : 0;  /* Number of arguments */
-      int no_such_func = 0;       /* True if no such function exists */
-      int wrong_num_args = 0;     /* True if wrong number of arguments */
-      int is_agg = 0;             /* True if is an aggregate function */
-      int i;
-      int auth;                   /* Authorization to use the function */
-      int nId;                    /* Number of characters in function name */
-      const char *zId;            /* The function name. */
-      FuncDef *pDef;              /* Information about the function */
-      int enc = ENC(pParse->db);  /* The database encoding */
+/* Opcode: ToInt P1 * * * *
+**
+** Force the value in register P1 be an integer.  If
+** The value is currently a real number, drop its fractional part.
+** If the value is text or blob, try to convert it to an integer using the
+** equivalent of atoi() and store 0 if no such conversion is possible.
+**
+** A NULL value is not changed by this routine.  It remains NULL.
+*/
+case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
+  if( (pIn1->flags & MEM_Null)==0 ){
+    sqlite3VdbeMemIntegerify(pIn1);
+  }
+  break;
+}
 
-      zId = (char*)pExpr->token.z;
-      nId = pExpr->token.n;
-      pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
-      if( pDef==0 ){
-        pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, enc, 0);
-        if( pDef==0 ){
-          no_such_func = 1;
-        }else{
-          wrong_num_args = 1;
-        }
-      }else{
-        is_agg = pDef->xFunc==0;
-      }
-#ifndef SQLITE_OMIT_AUTHORIZATION
-      if( pDef ){
-        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);
-        if( auth!=SQLITE_OK ){
-          if( auth==SQLITE_DENY ){
-            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",
-                                    pDef->zName);
-            pNC->nErr++;
-          }
-          pExpr->op = TK_NULL;
-          return 1;
-        }
-      }
-#endif
-      if( is_agg && !pNC->allowAgg ){
-        sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId);
-        pNC->nErr++;
-        is_agg = 0;
-      }else if( no_such_func ){
-        sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
-        pNC->nErr++;
-      }else if( wrong_num_args ){
-        sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
-             nId, zId);
-        pNC->nErr++;
-      }
-      if( is_agg ){
-        pExpr->op = TK_AGG_FUNCTION;
-        pNC->hasAgg = 1;
-      }
-      if( is_agg ) pNC->allowAgg = 0;
-      for(i=0; pNC->nErr==0 && i<n; i++){
-        walkExprTree(pList->a[i].pExpr, nameResolverStep, pNC);
-      }
-      if( is_agg ) pNC->allowAgg = 1;
-      /* FIX ME:  Compute pExpr->affinity based on the expected return
-      ** type of the function 
+#ifndef SQLITE_OMIT_CAST
+/* Opcode: ToReal P1 * * * *
+**
+** Force the value in register P1 to be a floating point number.
+** If The value is currently an integer, convert it.
+** If the value is text or blob, try to convert it to an integer using the
+** equivalent of atoi() and store 0.0 if no such conversion is possible.
+**
+** A NULL value is not changed by this routine.  It remains NULL.
+*/
+case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
+  if( (pIn1->flags & MEM_Null)==0 ){
+    sqlite3VdbeMemRealify(pIn1);
+  }
+  break;
+}
+#endif /* SQLITE_OMIT_CAST */
+
+/* Opcode: Lt P1 P2 P3 P4 P5
+**
+** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
+** jump to address P2.  
+**
+** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
+** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
+** bit is clear then fall thru if either operand is NULL.
+**
+** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
+** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 
+** to coerce both inputs according to this affinity before the
+** comparison is made. If the SQLITE_AFF_MASK is 0x00, then numeric
+** affinity is used. Note that the affinity conversions are stored
+** back into the input registers P1 and P3.  So this opcode can cause
+** persistent changes to registers P1 and P3.
+**
+** Once any conversions have taken place, and neither value is NULL, 
+** the values are compared. If both values are blobs then memcmp() is
+** used to determine the results of the comparison.  If both values
+** are text, then the appropriate collating function specified in
+** P4 is  used to do the comparison.  If P4 is not specified then
+** memcmp() is used to compare text string.  If both values are
+** numeric, then a numeric comparison is used. If the two values
+** are of different types, then numbers are considered less than
+** strings and strings are considered less than blobs.
+**
+** If the SQLITE_STOREP2 bit of P5 is set, then do not jump.  Instead,
+** store a boolean result (either 0, or 1, or NULL) in register P2.
+*/
+/* Opcode: Ne P1 P2 P3 P4 P5
+**
+** This works just like the Lt opcode except that the jump is taken if
+** the operands in registers P1 and P3 are not equal.  See the Lt opcode for
+** additional information.
+**
+** If SQLITE_NULLEQ is set in P5 then the result of comparison is always either
+** true or false and is never NULL.  If both operands are NULL then the result
+** of comparison is false.  If either operand is NULL then the result is true.
+** If neither operand is NULL the the result is the same as it would be if
+** the SQLITE_NULLEQ flag were omitted from P5.
+*/
+/* Opcode: Eq P1 P2 P3 P4 P5
+**
+** This works just like the Lt opcode except that the jump is taken if
+** the operands in registers P1 and P3 are equal.
+** See the Lt opcode for additional information.
+**
+** If SQLITE_NULLEQ is set in P5 then the result of comparison is always either
+** true or false and is never NULL.  If both operands are NULL then the result
+** of comparison is true.  If either operand is NULL then the result is false.
+** If neither operand is NULL the the result is the same as it would be if
+** the SQLITE_NULLEQ flag were omitted from P5.
+*/
+/* Opcode: Le P1 P2 P3 P4 P5
+**
+** This works just like the Lt opcode except that the jump is taken if
+** the content of register P3 is less than or equal to the content of
+** register P1.  See the Lt opcode for additional information.
+*/
+/* Opcode: Gt P1 P2 P3 P4 P5
+**
+** This works just like the Lt opcode except that the jump is taken if
+** the content of register P3 is greater than the content of
+** register P1.  See the Lt opcode for additional information.
+*/
+/* Opcode: Ge P1 P2 P3 P4 P5
+**
+** This works just like the Lt opcode except that the jump is taken if
+** the content of register P3 is greater than or equal to the content of
+** register P1.  See the Lt opcode for additional information.
+*/
+case OP_Eq:               /* same as TK_EQ, jump, in1, in3 */
+case OP_Ne:               /* same as TK_NE, jump, in1, in3 */
+case OP_Lt:               /* same as TK_LT, jump, in1, in3 */
+case OP_Le:               /* same as TK_LE, jump, in1, in3 */
+case OP_Gt:               /* same as TK_GT, jump, in1, in3 */
+case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
+#if 0  /* local variables moved into u.ai */
+  int res;            /* Result of the comparison of pIn1 against pIn3 */
+  char affinity;      /* Affinity to use for comparison */
+#endif /* local variables moved into u.ai */
+
+  if( (pIn1->flags | pIn3->flags)&MEM_Null ){
+    /* One or both operands are NULL */
+    if( pOp->p5 & SQLITE_NULLEQ ){
+      /* If SQLITE_NULLEQ is set (which will only happen if the operator is
+      ** OP_Eq or OP_Ne) then take the jump or not depending on whether
+      ** or not both operands are null.
       */
-      return is_agg;
-    }
-#ifndef SQLITE_OMIT_SUBQUERY
-    case TK_SELECT:
-    case TK_EXISTS:
-#endif
-    case TK_IN: {
-      if( pExpr->pSelect ){
-        int nRef = pNC->nRef;
-#ifndef SQLITE_OMIT_CHECK
-        if( pNC->isCheck ){
-          sqlite3ErrorMsg(pParse,"subqueries prohibited in CHECK constraints");
-        }
-#endif
-        sqlite3SelectResolve(pParse, pExpr->pSelect, pNC);
-        assert( pNC->nRef>=nRef );
-        if( nRef!=pNC->nRef ){
-          ExprSetProperty(pExpr, EP_VarSelect);
-        }
+      assert( pOp->opcode==OP_Eq || pOp->opcode==OP_Ne );
+      u.ai.res = (pIn1->flags & pIn3->flags & MEM_Null)==0;
+    }else{
+      /* SQLITE_NULLEQ is clear and at least one operand is NULL,
+      ** then the result is always NULL.
+      ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
+      */
+      if( pOp->p5 & SQLITE_STOREP2 ){
+        pOut = &p->aMem[pOp->p2];
+        MemSetTypeFlag(pOut, MEM_Null);
+        REGISTER_TRACE(pOp->p2, pOut);
+      }else if( pOp->p5 & SQLITE_JUMPIFNULL ){
+        pc = pOp->p2-1;
       }
       break;
     }
-#ifndef SQLITE_OMIT_CHECK
-    case TK_VARIABLE: {
-      if( pNC->isCheck ){
-        sqlite3ErrorMsg(pParse,"parameters prohibited in CHECK constraints");
-      }
-      break;
+  }else{
+    /* Neither operand is NULL.  Do a comparison. */
+    u.ai.affinity = pOp->p5 & SQLITE_AFF_MASK;
+    if( u.ai.affinity ){
+      applyAffinity(pIn1, u.ai.affinity, encoding);
+      applyAffinity(pIn3, u.ai.affinity, encoding);
+      if( db->mallocFailed ) goto no_mem;
     }
-#endif
+
+    assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
+    ExpandBlob(pIn1);
+    ExpandBlob(pIn3);
+    u.ai.res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
   }
-  return 0;
+  switch( pOp->opcode ){
+    case OP_Eq:    u.ai.res = u.ai.res==0;     break;
+    case OP_Ne:    u.ai.res = u.ai.res!=0;     break;
+    case OP_Lt:    u.ai.res = u.ai.res<0;      break;
+    case OP_Le:    u.ai.res = u.ai.res<=0;     break;
+    case OP_Gt:    u.ai.res = u.ai.res>0;      break;
+    default:       u.ai.res = u.ai.res>=0;     break;
+  }
+
+  if( pOp->p5 & SQLITE_STOREP2 ){
+    pOut = &p->aMem[pOp->p2];
+    MemSetTypeFlag(pOut, MEM_Int);
+    pOut->u.i = u.ai.res;
+    REGISTER_TRACE(pOp->p2, pOut);
+  }else if( u.ai.res ){
+    pc = pOp->p2-1;
+  }
+  break;
 }
 
-/*
-** This routine walks an expression tree and resolves references to
-** table columns.  Nodes of the form ID.ID or ID resolve into an
-** index to the table in the table list and a column offset.  The 
-** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable
-** value is changed to the index of the referenced table in pTabList
-** plus the "base" value.  The base value will ultimately become the
-** VDBE cursor number for a cursor that is pointing into the referenced
-** table.  The Expr.iColumn value is changed to the index of the column 
-** of the referenced table.  The Expr.iColumn value for the special
-** ROWID column is -1.  Any INTEGER PRIMARY KEY column is tried as an
-** alias for ROWID.
-**
-** Also resolve function names and check the functions for proper
-** usage.  Make sure all function names are recognized and all functions
-** have the correct number of arguments.  Leave an error message
-** in pParse->zErrMsg if anything is amiss.  Return the number of errors.
-**
-** If the expression contains aggregate functions then set the EP_Agg
-** property on the expression.
-*/
-SQLITE_PRIVATE int sqlite3ExprResolveNames( 
-  NameContext *pNC,       /* Namespace to resolve expressions in. */
-  Expr *pExpr             /* The expression to be analyzed. */
-){
-  int savedHasAgg;
+/* Opcode: Permutation * * * P4 *
+**
+** Set the permutation used by the OP_Compare operator to be the array
+** of integers in P4.
+**
+** The permutation is only valid until the next OP_Permutation, OP_Compare,
+** OP_Halt, or OP_ResultRow.  Typically the OP_Permutation should occur
+** immediately prior to the OP_Compare.
+*/
+case OP_Permutation: {
+  assert( pOp->p4type==P4_INTARRAY );
+  assert( pOp->p4.ai );
+  aPermute = pOp->p4.ai;
+  break;
+}
 
-  if( pExpr==0 ) return 0;
-#if SQLITE_MAX_EXPR_DEPTH>0
-  {
-    int mxDepth = pNC->pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH];
-    if( (pExpr->nHeight+pNC->pParse->nHeight)>mxDepth ){
-      sqlite3ErrorMsg(pNC->pParse, 
-         "Expression tree is too large (maximum depth %d)", mxDepth
-      );
-      return 1;
+/* Opcode: Compare P1 P2 P3 P4 *
+**
+** Compare to vectors of registers in reg(P1)..reg(P1+P3-1) (all this
+** one "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
+** the comparison for use by the next OP_Jump instruct.
+**
+** P4 is a KeyInfo structure that defines collating sequences and sort
+** orders for the comparison.  The permutation applies to registers
+** only.  The KeyInfo elements are used sequentially.
+**
+** The comparison is a sort comparison, so NULLs compare equal,
+** NULLs are less than numbers, numbers are less than strings,
+** and strings are less than blobs.
+*/
+case OP_Compare: {
+#if 0  /* local variables moved into u.aj */
+  int n;
+  int i;
+  int p1;
+  int p2;
+  const KeyInfo *pKeyInfo;
+  int idx;
+  CollSeq *pColl;    /* Collating sequence to use on this term */
+  int bRev;          /* True for DESCENDING sort order */
+#endif /* local variables moved into u.aj */
+
+  u.aj.n = pOp->p3;
+  u.aj.pKeyInfo = pOp->p4.pKeyInfo;
+  assert( u.aj.n>0 );
+  assert( u.aj.pKeyInfo!=0 );
+  u.aj.p1 = pOp->p1;
+  u.aj.p2 = pOp->p2;
+#if SQLITE_DEBUG
+  if( aPermute ){
+    int k, mx = 0;
+    for(k=0; k<u.aj.n; k++) if( aPermute[k]>mx ) mx = aPermute[k];
+    assert( u.aj.p1>0 && u.aj.p1+mx<=p->nMem+1 );
+    assert( u.aj.p2>0 && u.aj.p2+mx<=p->nMem+1 );
+  }else{
+    assert( u.aj.p1>0 && u.aj.p1+u.aj.n<=p->nMem+1 );
+    assert( u.aj.p2>0 && u.aj.p2+u.aj.n<=p->nMem+1 );
+  }
+#endif /* SQLITE_DEBUG */
+  for(u.aj.i=0; u.aj.i<u.aj.n; u.aj.i++){
+    u.aj.idx = aPermute ? aPermute[u.aj.i] : u.aj.i;
+    REGISTER_TRACE(u.aj.p1+u.aj.idx, &p->aMem[u.aj.p1+u.aj.idx]);
+    REGISTER_TRACE(u.aj.p2+u.aj.idx, &p->aMem[u.aj.p2+u.aj.idx]);
+    assert( u.aj.i<u.aj.pKeyInfo->nField );
+    u.aj.pColl = u.aj.pKeyInfo->aColl[u.aj.i];
+    u.aj.bRev = u.aj.pKeyInfo->aSortOrder[u.aj.i];
+    iCompare = sqlite3MemCompare(&p->aMem[u.aj.p1+u.aj.idx], &p->aMem[u.aj.p2+u.aj.idx], u.aj.pColl);
+    if( iCompare ){
+      if( u.aj.bRev ) iCompare = -iCompare;
+      break;
     }
-    pNC->pParse->nHeight += pExpr->nHeight;
   }
-#endif
-  savedHasAgg = pNC->hasAgg;
-  pNC->hasAgg = 0;
-  walkExprTree(pExpr, nameResolverStep, pNC);
-#if SQLITE_MAX_EXPR_DEPTH>0
-  pNC->pParse->nHeight -= pExpr->nHeight;
-#endif
-  if( pNC->nErr>0 ){
-    ExprSetProperty(pExpr, EP_Error);
+  aPermute = 0;
+  break;
+}
+
+/* Opcode: Jump P1 P2 P3 * *
+**
+** Jump to the instruction at address P1, P2, or P3 depending on whether
+** in the most recent OP_Compare instruction the P1 vector was less than
+** equal to, or greater than the P2 vector, respectively.
+*/
+case OP_Jump: {             /* jump */
+  if( iCompare<0 ){
+    pc = pOp->p1 - 1;
+  }else if( iCompare==0 ){
+    pc = pOp->p2 - 1;
+  }else{
+    pc = pOp->p3 - 1;
   }
-  if( pNC->hasAgg ){
-    ExprSetProperty(pExpr, EP_Agg);
-  }else if( savedHasAgg ){
-    pNC->hasAgg = 1;
+  break;
+}
+
+/* Opcode: And P1 P2 P3 * *
+**
+** Take the logical AND of the values in registers P1 and P2 and
+** write the result into register P3.
+**
+** If either P1 or P2 is 0 (false) then the result is 0 even if
+** the other input is NULL.  A NULL and true or two NULLs give
+** a NULL output.
+*/
+/* Opcode: Or P1 P2 P3 * *
+**
+** Take the logical OR of the values in register P1 and P2 and
+** store the answer in register P3.
+**
+** If either P1 or P2 is nonzero (true) then the result is 1 (true)
+** even if the other input is NULL.  A NULL and false or two NULLs
+** give a NULL output.
+*/
+case OP_And:              /* same as TK_AND, in1, in2, out3 */
+case OP_Or: {             /* same as TK_OR, in1, in2, out3 */
+#if 0  /* local variables moved into u.ak */
+  int v1;    /* Left operand:  0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
+  int v2;    /* Right operand: 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
+#endif /* local variables moved into u.ak */
+
+  if( pIn1->flags & MEM_Null ){
+    u.ak.v1 = 2;
+  }else{
+    u.ak.v1 = sqlite3VdbeIntValue(pIn1)!=0;
   }
-  return ExprHasProperty(pExpr, EP_Error);
+  if( pIn2->flags & MEM_Null ){
+    u.ak.v2 = 2;
+  }else{
+    u.ak.v2 = sqlite3VdbeIntValue(pIn2)!=0;
+  }
+  if( pOp->opcode==OP_And ){
+    static const unsigned char and_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
+    u.ak.v1 = and_logic[u.ak.v1*3+u.ak.v2];
+  }else{
+    static const unsigned char or_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
+    u.ak.v1 = or_logic[u.ak.v1*3+u.ak.v2];
+  }
+  if( u.ak.v1==2 ){
+    MemSetTypeFlag(pOut, MEM_Null);
+  }else{
+    pOut->u.i = u.ak.v1;
+    MemSetTypeFlag(pOut, MEM_Int);
+  }
+  break;
 }
 
-/*
-** A pointer instance of this structure is used to pass information
-** through walkExprTree into codeSubqueryStep().
+/* Opcode: Not P1 P2 * * *
+**
+** Interpret the value in register P1 as a boolean value.  Store the
+** boolean complement in register P2.  If the value in register P1 is 
+** NULL, then a NULL is stored in P2.
 */
-typedef struct QueryCoder QueryCoder;
-struct QueryCoder {
-  Parse *pParse;       /* The parsing context */
-  NameContext *pNC;    /* Namespace of first enclosing query */
-};
+case OP_Not: {                /* same as TK_NOT, in1 */
+  pOut = &p->aMem[pOp->p2];
+  if( pIn1->flags & MEM_Null ){
+    sqlite3VdbeMemSetNull(pOut);
+  }else{
+    sqlite3VdbeMemSetInt64(pOut, !sqlite3VdbeIntValue(pIn1));
+  }
+  break;
+}
 
-#ifdef SQLITE_TEST
-  int sqlite3_enable_in_opt = 1;
-#else
-  #define sqlite3_enable_in_opt 1
-#endif
+/* Opcode: BitNot P1 P2 * * *
+**
+** Interpret the content of register P1 as an integer.  Store the
+** ones-complement of the P1 value into register P2.  If P1 holds
+** a NULL then store a NULL in P2.
+*/
+case OP_BitNot: {             /* same as TK_BITNOT, in1 */
+  pOut = &p->aMem[pOp->p2];
+  if( pIn1->flags & MEM_Null ){
+    sqlite3VdbeMemSetNull(pOut);
+  }else{
+    sqlite3VdbeMemSetInt64(pOut, ~sqlite3VdbeIntValue(pIn1));
+  }
+  break;
+}
 
-/*
-** Return true if the IN operator optimization is enabled and
-** the SELECT statement p exists and is of the
-** simple form:
+/* Opcode: If P1 P2 P3 * *
 **
-**     SELECT <column> FROM <table>
+** Jump to P2 if the value in register P1 is true.  The value is
+** is considered true if it is numeric and non-zero.  If the value
+** in P1 is NULL then take the jump if P3 is true.
+*/
+/* Opcode: IfNot P1 P2 P3 * *
 **
-** If this is the case, it may be possible to use an existing table
-** or index instead of generating an epheremal table.
+** Jump to P2 if the value in register P1 is False.  The value is
+** is considered true if it has a numeric value of zero.  If the value
+** in P1 is NULL then take the jump if P3 is true.
 */
-#ifndef SQLITE_OMIT_SUBQUERY
-static int isCandidateForInOpt(Select *p){
-  SrcList *pSrc;
-  ExprList *pEList;
-  Table *pTab;
-  if( !sqlite3_enable_in_opt ) return 0; /* IN optimization must be enabled */
-  if( p==0 ) return 0;                   /* right-hand side of IN is SELECT */
-  if( p->pPrior ) return 0;              /* Not a compound SELECT */
-  if( p->isDistinct ) return 0;          /* No DISTINCT keyword */
-  if( p->isAgg ) return 0;               /* Contains no aggregate functions */
-  if( p->pGroupBy ) return 0;            /* Has no GROUP BY clause */
-  if( p->pLimit ) return 0;              /* Has no LIMIT clause */
-  if( p->pOffset ) return 0;
-  if( p->pWhere ) return 0;              /* Has no WHERE clause */
-  pSrc = p->pSrc;
-  if( pSrc==0 ) return 0;                /* A single table in the FROM clause */
-  if( pSrc->nSrc!=1 ) return 0;
-  if( pSrc->a[0].pSelect ) return 0;     /* FROM clause is not a subquery */
-  pTab = pSrc->a[0].pTab;
-  if( pTab==0 ) return 0;
-  if( pTab->pSelect ) return 0;          /* FROM clause is not a view */
-  if( IsVirtual(pTab) ) return 0;        /* FROM clause not a virtual table */
-  pEList = p->pEList;
-  if( pEList->nExpr!=1 ) return 0;       /* One column in the result set */
-  if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
-  return 1;
+case OP_If:                 /* jump, in1 */
+case OP_IfNot: {            /* jump, in1 */
+#if 0  /* local variables moved into u.al */
+  int c;
+#endif /* local variables moved into u.al */
+  if( pIn1->flags & MEM_Null ){
+    u.al.c = pOp->p3;
+  }else{
+#ifdef SQLITE_OMIT_FLOATING_POINT
+    u.al.c = sqlite3VdbeIntValue(pIn1)!=0;
+#else
+    u.al.c = sqlite3VdbeRealValue(pIn1)!=0.0;
+#endif
+    if( pOp->opcode==OP_IfNot ) u.al.c = !u.al.c;
+  }
+  if( u.al.c ){
+    pc = pOp->p2-1;
+  }
+  break;
 }
-#endif /* SQLITE_OMIT_SUBQUERY */
 
-/*
-** This function is used by the implementation of the IN (...) operator.
-** It's job is to find or create a b-tree structure that may be used
-** either to test for membership of the (...) set or to iterate through
-** its members, skipping duplicates.
+/* Opcode: IsNull P1 P2 * * *
 **
-** The cursor opened on the structure (database table, database index 
-** or ephermal table) is stored in pX->iTable before this function returns.
-** The returned value indicates the structure type, as follows:
+** Jump to P2 if the value in register P1 is NULL.
+*/
+case OP_IsNull: {            /* same as TK_ISNULL, jump, in1 */
+  if( (pIn1->flags & MEM_Null)!=0 ){
+    pc = pOp->p2 - 1;
+  }
+  break;
+}
+
+/* Opcode: NotNull P1 P2 * * *
 **
-**   IN_INDEX_ROWID - The cursor was opened on a database table.
-**   IN_INDEX_INDEX - The cursor was opened on a database index.
-**   IN_INDEX_EPH -   The cursor was opened on a specially created and
-**                    populated epheremal table.
+** Jump to P2 if the value in register P1 is not NULL.  
+*/
+case OP_NotNull: {            /* same as TK_NOTNULL, jump, in1 */
+  if( (pIn1->flags & MEM_Null)==0 ){
+    pc = pOp->p2 - 1;
+  }
+  break;
+}
+
+/* Opcode: Column P1 P2 P3 P4 P5
 **
-** An existing structure may only be used if the SELECT is of the simple
-** form:
+** Interpret the data that cursor P1 points to as a structure built using
+** the MakeRecord instruction.  (See the MakeRecord opcode for additional
+** information about the format of the data.)  Extract the P2-th column
+** from this record.  If there are less that (P2+1) 
+** values in the record, extract a NULL.
 **
-**     SELECT <column> FROM <table>
+** The value extracted is stored in register P3.
 **
-** If the mustBeUnique parameter is false, the structure will be used 
-** for fast set membership tests. In this case an epheremal table must 
-** be used unless <column> is an INTEGER PRIMARY KEY or an index can 
-** be found with <column> as its left-most column.
+** If the column contains fewer than P2 fields, then extract a NULL.  Or,
+** if the P4 argument is a P4_MEM use the value of the P4 argument as
+** the result.
 **
-** If mustBeUnique is true, then the structure will be used to iterate
-** through the set members, skipping any duplicates. In this case an
-** epheremal table must be used unless the selected <column> is guaranteed
-** to be unique - either because it is an INTEGER PRIMARY KEY or it
-** is unique by virtue of a constraint or implicit index.
+** If the OPFLAG_CLEARCACHE bit is set on P5 and P1 is a pseudo-table cursor,
+** then the cache of the cursor is reset prior to extracting the column.
+** The first OP_Column against a pseudo-table after the value of the content
+** register has changed should have this bit set.
 */
-#ifndef SQLITE_OMIT_SUBQUERY
-SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int mustBeUnique){
-  Select *p;
-  int eType = 0;
-  int iTab = pParse->nTab++;
+case OP_Column: {
+#if 0  /* local variables moved into u.am */
+  u32 payloadSize;   /* Number of bytes in the record */
+  i64 payloadSize64; /* Number of bytes in the record */
+  int p1;            /* P1 value of the opcode */
+  int p2;            /* column number to retrieve */
+  VdbeCursor *pC;    /* The VDBE cursor */
+  char *zRec;        /* Pointer to complete record-data */
+  BtCursor *pCrsr;   /* The BTree cursor */
+  u32 *aType;        /* aType[i] holds the numeric type of the i-th column */
+  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
+  int nField;        /* number of fields in the record */
+  int len;           /* The length of the serialized data for the column */
+  int i;             /* Loop counter */
+  char *zData;       /* Part of the record being decoded */
+  Mem *pDest;        /* Where to write the extracted value */
+  Mem sMem;          /* For storing the record being decoded */
+  u8 *zIdx;          /* Index into header */
+  u8 *zEndHdr;       /* Pointer to first byte after the header */
+  u32 offset;        /* Offset into the data */
+  u64 offset64;      /* 64-bit offset.  64 bits needed to catch overflow */
+  int szHdr;         /* Size of the header size field at start of record */
+  int avail;         /* Number of bytes of available data */
+  Mem *pReg;         /* PseudoTable input register */
+#endif /* local variables moved into u.am */
+
+
+  u.am.p1 = pOp->p1;
+  u.am.p2 = pOp->p2;
+  u.am.pC = 0;
+  memset(&u.am.sMem, 0, sizeof(u.am.sMem));
+  assert( u.am.p1<p->nCursor );
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  u.am.pDest = &p->aMem[pOp->p3];
+  MemSetTypeFlag(u.am.pDest, MEM_Null);
+  u.am.zRec = 0;
 
-  /* The follwing if(...) expression is true if the SELECT is of the 
-  ** simple form:
+  /* This block sets the variable u.am.payloadSize to be the total number of
+  ** bytes in the record.
   **
-  **     SELECT <column> FROM <table>
+  ** u.am.zRec is set to be the complete text of the record if it is available.
+  ** The complete record text is always available for pseudo-tables
+  ** If the record is stored in a cursor, the complete record text
+  ** might be available in the  u.am.pC->aRow cache.  Or it might not be.
+  ** If the data is unavailable,  u.am.zRec is set to NULL.
   **
-  ** If this is the case, it may be possible to use an existing table
-  ** or index instead of generating an epheremal table.
+  ** We also compute the number of columns in the record.  For cursors,
+  ** the number of columns is stored in the VdbeCursor.nField element.
   */
-  p = pX->pSelect;
-  if( isCandidateForInOpt(p) ){
-    sqlite3 *db = pParse->db;
-    Index *pIdx;
-    Expr *pExpr = p->pEList->a[0].pExpr;
-    int iCol = pExpr->iColumn;
-    Vdbe *v = sqlite3GetVdbe(pParse);
+  u.am.pC = p->apCsr[u.am.p1];
+  assert( u.am.pC!=0 );
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  assert( u.am.pC->pVtabCursor==0 );
+#endif
+  u.am.pCrsr = u.am.pC->pCursor;
+  if( u.am.pCrsr!=0 ){
+    /* The record is stored in a B-Tree */
+    rc = sqlite3VdbeCursorMoveto(u.am.pC);
+    if( rc ) goto abort_due_to_error;
+    if( u.am.pC->nullRow ){
+      u.am.payloadSize = 0;
+    }else if( u.am.pC->cacheStatus==p->cacheCtr ){
+      u.am.payloadSize = u.am.pC->payloadSize;
+      u.am.zRec = (char*)u.am.pC->aRow;
+    }else if( u.am.pC->isIndex ){
+      assert( sqlite3BtreeCursorIsValid(u.am.pCrsr) );
+      rc = sqlite3BtreeKeySize(u.am.pCrsr, &u.am.payloadSize64);
+      assert( rc==SQLITE_OK );   /* True because of CursorMoveto() call above */
+      /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
+      ** payload size, so it is impossible for u.am.payloadSize64 to be
+      ** larger than 32 bits. */
+      assert( (u.am.payloadSize64 & SQLITE_MAX_U32)==(u64)u.am.payloadSize64 );
+      u.am.payloadSize = (u32)u.am.payloadSize64;
+    }else{
+      assert( sqlite3BtreeCursorIsValid(u.am.pCrsr) );
+      rc = sqlite3BtreeDataSize(u.am.pCrsr, &u.am.payloadSize);
+      assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
+    }
+  }else if( u.am.pC->pseudoTableReg>0 ){
+    u.am.pReg = &p->aMem[u.am.pC->pseudoTableReg];
+    assert( u.am.pReg->flags & MEM_Blob );
+    u.am.payloadSize = u.am.pReg->n;
+    u.am.zRec = u.am.pReg->z;
+    u.am.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
+    assert( u.am.payloadSize==0 || u.am.zRec!=0 );
+  }else{
+    /* Consider the row to be NULL */
+    u.am.payloadSize = 0;
+  }
 
-    /* This function is only called from two places. In both cases the vdbe
-    ** has already been allocated. So assume sqlite3GetVdbe() is always
-    ** successful here.
-    */
-    assert(v);
-    if( iCol<0 ){
-      int iMem = ++pParse->nMem;
-      int iAddr;
-      Table *pTab = p->pSrc->a[0].pTab;
-      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-      sqlite3VdbeUsesBtree(v, iDb);
+  /* If u.am.payloadSize is 0, then just store a NULL */
+  if( u.am.payloadSize==0 ){
+    assert( u.am.pDest->flags&MEM_Null );
+    goto op_column_out;
+  }
+  assert( db->aLimit[SQLITE_LIMIT_LENGTH]>=0 );
+  if( u.am.payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    goto too_big;
+  }
 
-      iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
+  u.am.nField = u.am.pC->nField;
+  assert( u.am.p2<u.am.nField );
 
-      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
-      eType = IN_INDEX_ROWID;
+  /* Read and parse the table header.  Store the results of the parse
+  ** into the record header cache fields of the cursor.
+  */
+  u.am.aType = u.am.pC->aType;
+  if( u.am.pC->cacheStatus==p->cacheCtr ){
+    u.am.aOffset = u.am.pC->aOffset;
+  }else{
+    assert(u.am.aType);
+    u.am.avail = 0;
+    u.am.pC->aOffset = u.am.aOffset = &u.am.aType[u.am.nField];
+    u.am.pC->payloadSize = u.am.payloadSize;
+    u.am.pC->cacheStatus = p->cacheCtr;
 
-      sqlite3VdbeJumpHere(v, iAddr);
+    /* Figure out how many bytes are in the header */
+    if( u.am.zRec ){
+      u.am.zData = u.am.zRec;
     }else{
-      /* The collation sequence used by the comparison. If an index is to 
-      ** be used in place of a temp-table, it must be ordered according
-      ** to this collation sequence.
-      */
-      CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
-
-      /* Check that the affinity that will be used to perform the 
-      ** comparison is the same as the affinity of the column. If
-      ** it is not, it is not possible to use any index.
+      if( u.am.pC->isIndex ){
+        u.am.zData = (char*)sqlite3BtreeKeyFetch(u.am.pCrsr, &u.am.avail);
+      }else{
+        u.am.zData = (char*)sqlite3BtreeDataFetch(u.am.pCrsr, &u.am.avail);
+      }
+      /* If KeyFetch()/DataFetch() managed to get the entire payload,
+      ** save the payload in the u.am.pC->aRow cache.  That will save us from
+      ** having to make additional calls to fetch the content portion of
+      ** the record.
       */
-      Table *pTab = p->pSrc->a[0].pTab;
-      char aff = comparisonAffinity(pX);
-      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
-
-      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
-        if( (pIdx->aiColumn[0]==iCol)
-         && (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))
-         && (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
-        ){
-          int iDb;
-          int iMem = ++pParse->nMem;
-          int iAddr;
-          char *pKey;
-  
-          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
-          iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
-          sqlite3VdbeUsesBtree(v, iDb);
-
-          iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
-          sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
-  
-          sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIdx->nColumn);
-          sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
-                               pKey,P4_KEYINFO_HANDOFF);
-          VdbeComment((v, "%s", pIdx->zName));
-          eType = IN_INDEX_INDEX;
-
-          sqlite3VdbeJumpHere(v, iAddr);
-        }
+      assert( u.am.avail>=0 );
+      if( u.am.payloadSize <= (u32)u.am.avail ){
+        u.am.zRec = u.am.zData;
+        u.am.pC->aRow = (u8*)u.am.zData;
+      }else{
+        u.am.pC->aRow = 0;
       }
     }
-  }
+    /* The following assert is true in all cases accept when
+    ** the database file has been corrupted externally.
+    **    assert( u.am.zRec!=0 || u.am.avail>=u.am.payloadSize || u.am.avail>=9 ); */
+    u.am.szHdr = getVarint32((u8*)u.am.zData, u.am.offset);
 
-  if( eType==0 ){
-    sqlite3CodeSubselect(pParse, pX);
-    eType = IN_INDEX_EPH;
+    /* Make sure a corrupt database has not given us an oversize header.
+    ** Do this now to avoid an oversize memory allocation.
+    **
+    ** Type entries can be between 1 and 5 bytes each.  But 4 and 5 byte
+    ** types use so much data space that there can only be 4096 and 32 of
+    ** them, respectively.  So the maximum header length results from a
+    ** 3-byte type for each of the maximum of 32768 columns plus three
+    ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
+    */
+    if( u.am.offset > 98307 ){
+      rc = SQLITE_CORRUPT_BKPT;
+      goto op_column_out;
+    }
+
+    /* Compute in u.am.len the number of bytes of data we need to read in order
+    ** to get u.am.nField type values.  u.am.offset is an upper bound on this.  But
+    ** u.am.nField might be significantly less than the true number of columns
+    ** in the table, and in that case, 5*u.am.nField+3 might be smaller than u.am.offset.
+    ** We want to minimize u.am.len in order to limit the size of the memory
+    ** allocation, especially if a corrupt database file has caused u.am.offset
+    ** to be oversized. Offset is limited to 98307 above.  But 98307 might
+    ** still exceed Robson memory allocation limits on some configurations.
+    ** On systems that cannot tolerate large memory allocations, u.am.nField*5+3
+    ** will likely be much smaller since u.am.nField will likely be less than
+    ** 20 or so.  This insures that Robson memory allocation limits are
+    ** not exceeded even for corrupt database files.
+    */
+    u.am.len = u.am.nField*5 + 3;
+    if( u.am.len > (int)u.am.offset ) u.am.len = (int)u.am.offset;
+
+    /* The KeyFetch() or DataFetch() above are fast and will get the entire
+    ** record header in most cases.  But they will fail to get the complete
+    ** record header if the record header does not fit on a single page
+    ** in the B-Tree.  When that happens, use sqlite3VdbeMemFromBtree() to
+    ** acquire the complete header text.
+    */
+    if( !u.am.zRec && u.am.avail<u.am.len ){
+      u.am.sMem.flags = 0;
+      u.am.sMem.db = 0;
+      rc = sqlite3VdbeMemFromBtree(u.am.pCrsr, 0, u.am.len, u.am.pC->isIndex, &u.am.sMem);
+      if( rc!=SQLITE_OK ){
+        goto op_column_out;
+      }
+      u.am.zData = u.am.sMem.z;
+    }
+    u.am.zEndHdr = (u8 *)&u.am.zData[u.am.len];
+    u.am.zIdx = (u8 *)&u.am.zData[u.am.szHdr];
+
+    /* Scan the header and use it to fill in the u.am.aType[] and u.am.aOffset[]
+    ** arrays.  u.am.aType[u.am.i] will contain the type integer for the u.am.i-th
+    ** column and u.am.aOffset[u.am.i] will contain the u.am.offset from the beginning
+    ** of the record to the start of the data for the u.am.i-th column
+    */
+    u.am.offset64 = u.am.offset;
+    for(u.am.i=0; u.am.i<u.am.nField; u.am.i++){
+      if( u.am.zIdx<u.am.zEndHdr ){
+        u.am.aOffset[u.am.i] = (u32)u.am.offset64;
+        u.am.zIdx += getVarint32(u.am.zIdx, u.am.aType[u.am.i]);
+        u.am.offset64 += sqlite3VdbeSerialTypeLen(u.am.aType[u.am.i]);
+      }else{
+        /* If u.am.i is less that u.am.nField, then there are less fields in this
+        ** record than SetNumColumns indicated there are columns in the
+        ** table. Set the u.am.offset for any extra columns not present in
+        ** the record to 0. This tells code below to store a NULL
+        ** instead of deserializing a value from the record.
+        */
+        u.am.aOffset[u.am.i] = 0;
+      }
+    }
+    sqlite3VdbeMemRelease(&u.am.sMem);
+    u.am.sMem.flags = MEM_Null;
+
+    /* If we have read more header data than was contained in the header,
+    ** or if the end of the last field appears to be past the end of the
+    ** record, or if the end of the last field appears to be before the end
+    ** of the record (when all fields present), then we must be dealing
+    ** with a corrupt database.
+    */
+    if( (u.am.zIdx > u.am.zEndHdr)|| (u.am.offset64 > u.am.payloadSize)
+     || (u.am.zIdx==u.am.zEndHdr && u.am.offset64!=(u64)u.am.payloadSize) ){
+      rc = SQLITE_CORRUPT_BKPT;
+      goto op_column_out;
+    }
+  }
+
+  /* Get the column information. If u.am.aOffset[u.am.p2] is non-zero, then
+  ** deserialize the value from the record. If u.am.aOffset[u.am.p2] is zero,
+  ** then there are not enough fields in the record to satisfy the
+  ** request.  In this case, set the value NULL or to P4 if P4 is
+  ** a pointer to a Mem object.
+  */
+  if( u.am.aOffset[u.am.p2] ){
+    assert( rc==SQLITE_OK );
+    if( u.am.zRec ){
+      sqlite3VdbeMemReleaseExternal(u.am.pDest);
+      sqlite3VdbeSerialGet((u8 *)&u.am.zRec[u.am.aOffset[u.am.p2]], u.am.aType[u.am.p2], u.am.pDest);
+    }else{
+      u.am.len = sqlite3VdbeSerialTypeLen(u.am.aType[u.am.p2]);
+      sqlite3VdbeMemMove(&u.am.sMem, u.am.pDest);
+      rc = sqlite3VdbeMemFromBtree(u.am.pCrsr, u.am.aOffset[u.am.p2], u.am.len, u.am.pC->isIndex, &u.am.sMem);
+      if( rc!=SQLITE_OK ){
+        goto op_column_out;
+      }
+      u.am.zData = u.am.sMem.z;
+      sqlite3VdbeSerialGet((u8*)u.am.zData, u.am.aType[u.am.p2], u.am.pDest);
+    }
+    u.am.pDest->enc = encoding;
   }else{
-    pX->iTable = iTab;
+    if( pOp->p4type==P4_MEM ){
+      sqlite3VdbeMemShallowCopy(u.am.pDest, pOp->p4.pMem, MEM_Static);
+    }else{
+      assert( u.am.pDest->flags&MEM_Null );
+    }
   }
-  return eType;
+
+  /* If we dynamically allocated space to hold the data (in the
+  ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
+  ** dynamically allocated space over to the u.am.pDest structure.
+  ** This prevents a memory copy.
+  */
+  if( u.am.sMem.zMalloc ){
+    assert( u.am.sMem.z==u.am.sMem.zMalloc );
+    assert( !(u.am.pDest->flags & MEM_Dyn) );
+    assert( !(u.am.pDest->flags & (MEM_Blob|MEM_Str)) || u.am.pDest->z==u.am.sMem.z );
+    u.am.pDest->flags &= ~(MEM_Ephem|MEM_Static);
+    u.am.pDest->flags |= MEM_Term;
+    u.am.pDest->z = u.am.sMem.z;
+    u.am.pDest->zMalloc = u.am.sMem.zMalloc;
+  }
+
+  rc = sqlite3VdbeMemMakeWriteable(u.am.pDest);
+
+op_column_out:
+  UPDATE_MAX_BLOBSIZE(u.am.pDest);
+  REGISTER_TRACE(pOp->p3, u.am.pDest);
+  break;
 }
-#endif
 
-/*
-** Generate code for scalar subqueries used as an expression
-** and IN operators.  Examples:
+/* Opcode: Affinity P1 P2 * P4 *
 **
-**     (SELECT a FROM b)          -- subquery
-**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
-**     x IN (4,5,11)              -- IN operator with list on right-hand side
-**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
+** Apply affinities to a range of P2 registers starting with P1.
 **
-** The pExpr parameter describes the expression that contains the IN
-** operator or subquery.
+** P4 is a string that is P2 characters long. The nth character of the
+** string indicates the column affinity that should be used for the nth
+** memory cell in the range.
 */
-#ifndef SQLITE_OMIT_SUBQUERY
-SQLITE_PRIVATE void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
-  int testAddr = 0;                       /* One-time test address */
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;
+case OP_Affinity: {
+#if 0  /* local variables moved into u.an */
+  char *zAffinity;   /* The affinity to be applied */
+  Mem *pData0;       /* First register to which to apply affinity */
+  Mem *pLast;        /* Last register to which to apply affinity */
+  Mem *pRec;         /* Current register */
+#endif /* local variables moved into u.an */
+
+  u.an.zAffinity = pOp->p4.z;
+  u.an.pData0 = &p->aMem[pOp->p1];
+  u.an.pLast = &u.an.pData0[pOp->p2-1];
+  for(u.an.pRec=u.an.pData0; u.an.pRec<=u.an.pLast; u.an.pRec++){
+    ExpandBlob(u.an.pRec);
+    applyAffinity(u.an.pRec, u.an.zAffinity[u.an.pRec-u.an.pData0], encoding);
+  }
+  break;
+}
 
+/* Opcode: MakeRecord P1 P2 P3 P4 *
+**
+** Convert P2 registers beginning with P1 into a single entry
+** suitable for use as a data record in a database table or as a key
+** in an index.  The details of the format are irrelevant as long as
+** the OP_Column opcode can decode the record later.
+** Refer to source code comments for the details of the record
+** format.
+**
+** P4 may be a string that is P2 characters long.  The nth character of the
+** string indicates the column affinity that should be used for the nth
+** field of the index key.
+**
+** The mapping from character to affinity is given by the SQLITE_AFF_
+** macros defined in sqliteInt.h.
+**
+** If P4 is NULL then all index fields have the affinity NONE.
+*/
+case OP_MakeRecord: {
+#if 0  /* local variables moved into u.ao */
+  u8 *zNewRecord;        /* A buffer to hold the data for the new record */
+  Mem *pRec;             /* The new record */
+  u64 nData;             /* Number of bytes of data space */
+  int nHdr;              /* Number of bytes of header space */
+  i64 nByte;             /* Data space required for this record */
+  int nZero;             /* Number of zero bytes at the end of the record */
+  int nVarint;           /* Number of bytes in a varint */
+  u32 serial_type;       /* Type field */
+  Mem *pData0;           /* First field to be combined into the record */
+  Mem *pLast;            /* Last field of the record */
+  int nField;            /* Number of fields in the record */
+  char *zAffinity;       /* The affinity string for the record */
+  int file_format;       /* File format to use for encoding */
+  int i;                 /* Space used in zNewRecord[] */
+  int len;               /* Length of a field */
+#endif /* local variables moved into u.ao */
 
-  /* This code must be run in its entirety every time it is encountered
-  ** if any of the following is true:
+  /* Assuming the record contains N fields, the record format looks
+  ** like this:
   **
-  **    *  The right-hand side is a correlated subquery
-  **    *  The right-hand side is an expression list containing variables
-  **    *  We are inside a trigger
+  ** ------------------------------------------------------------------------
+  ** | hdr-size | type 0 | type 1 | ... | type N-1 | data0 | ... | data N-1 |
+  ** ------------------------------------------------------------------------
   **
-  ** If all of the above are false, then we can run this code just once
-  ** save the results, and reuse the same result on subsequent invocations.
+  ** Data(0) is taken from register P1.  Data(1) comes from register P1+1
+  ** and so froth.
+  **
+  ** Each type field is a varint representing the serial type of the
+  ** corresponding data element (see sqlite3VdbeSerialType()). The
+  ** hdr-size field is also a varint which is the offset from the beginning
+  ** of the record to data0.
   */
-  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
-    int mem = ++pParse->nMem;
-    sqlite3VdbeAddOp1(v, OP_If, mem);
-    testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
-    assert( testAddr>0 || pParse->db->mallocFailed );
+  u.ao.nData = 0;         /* Number of bytes of data space */
+  u.ao.nHdr = 0;          /* Number of bytes of header space */
+  u.ao.nByte = 0;         /* Data space required for this record */
+  u.ao.nZero = 0;         /* Number of zero bytes at the end of the record */
+  u.ao.nField = pOp->p1;
+  u.ao.zAffinity = pOp->p4.z;
+  assert( u.ao.nField>0 && pOp->p2>0 && pOp->p2+u.ao.nField<=p->nMem+1 );
+  u.ao.pData0 = &p->aMem[u.ao.nField];
+  u.ao.nField = pOp->p2;
+  u.ao.pLast = &u.ao.pData0[u.ao.nField-1];
+  u.ao.file_format = p->minWriteFileFormat;
+
+  /* Loop through the elements that will make up the record to figure
+  ** out how much space is required for the new record.
+  */
+  for(u.ao.pRec=u.ao.pData0; u.ao.pRec<=u.ao.pLast; u.ao.pRec++){
+    if( u.ao.zAffinity ){
+      applyAffinity(u.ao.pRec, u.ao.zAffinity[u.ao.pRec-u.ao.pData0], encoding);
+    }
+    if( u.ao.pRec->flags&MEM_Zero && u.ao.pRec->n>0 ){
+      sqlite3VdbeMemExpandBlob(u.ao.pRec);
+    }
+    u.ao.serial_type = sqlite3VdbeSerialType(u.ao.pRec, u.ao.file_format);
+    u.ao.len = sqlite3VdbeSerialTypeLen(u.ao.serial_type);
+    u.ao.nData += u.ao.len;
+    u.ao.nHdr += sqlite3VarintLen(u.ao.serial_type);
+    if( u.ao.pRec->flags & MEM_Zero ){
+      /* Only pure zero-filled BLOBs can be input to this Opcode.
+      ** We do not allow blobs with a prefix and a zero-filled tail. */
+      u.ao.nZero += u.ao.pRec->u.nZero;
+    }else if( u.ao.len ){
+      u.ao.nZero = 0;
+    }
   }
 
-  switch( pExpr->op ){
-    case TK_IN: {
-      char affinity;
-      KeyInfo keyInfo;
-      int addr;        /* Address of OP_OpenEphemeral instruction */
+  /* Add the initial header varint and total the size */
+  u.ao.nHdr += u.ao.nVarint = sqlite3VarintLen(u.ao.nHdr);
+  if( u.ao.nVarint<sqlite3VarintLen(u.ao.nHdr) ){
+    u.ao.nHdr++;
+  }
+  u.ao.nByte = u.ao.nHdr+u.ao.nData-u.ao.nZero;
+  if( u.ao.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    goto too_big;
+  }
 
-      affinity = sqlite3ExprAffinity(pExpr->pLeft);
+  /* Make sure the output register has a buffer large enough to store
+  ** the new record. The output register (pOp->p3) is not allowed to
+  ** be one of the input registers (because the following call to
+  ** sqlite3VdbeMemGrow() could clobber the value before it is used).
+  */
+  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
+  pOut = &p->aMem[pOp->p3];
+  if( sqlite3VdbeMemGrow(pOut, (int)u.ao.nByte, 0) ){
+    goto no_mem;
+  }
+  u.ao.zNewRecord = (u8 *)pOut->z;
 
-      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
-      ** expression it is handled the same way. A virtual table is 
-      ** filled with single-field index keys representing the results
-      ** from the SELECT or the <exprlist>.
-      **
-      ** If the 'x' expression is a column value, or the SELECT...
-      ** statement returns a column value, then the affinity of that
-      ** column is used to build the index keys. If both 'x' and the
-      ** SELECT... statement are columns, then numeric affinity is used
-      ** if either column has NUMERIC or INTEGER affinity. If neither
-      ** 'x' nor the SELECT... statement are columns, then numeric affinity
-      ** is used.
-      */
-      pExpr->iTable = pParse->nTab++;
-      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, 1);
-      memset(&keyInfo, 0, sizeof(keyInfo));
-      keyInfo.nField = 1;
+  /* Write the record */
+  u.ao.i = putVarint32(u.ao.zNewRecord, u.ao.nHdr);
+  for(u.ao.pRec=u.ao.pData0; u.ao.pRec<=u.ao.pLast; u.ao.pRec++){
+    u.ao.serial_type = sqlite3VdbeSerialType(u.ao.pRec, u.ao.file_format);
+    u.ao.i += putVarint32(&u.ao.zNewRecord[u.ao.i], u.ao.serial_type);      /* serial type */
+  }
+  for(u.ao.pRec=u.ao.pData0; u.ao.pRec<=u.ao.pLast; u.ao.pRec++){  /* serial data */
+    u.ao.i += sqlite3VdbeSerialPut(&u.ao.zNewRecord[u.ao.i], (int)(u.ao.nByte-u.ao.i), u.ao.pRec,u.ao.file_format);
+  }
+  assert( u.ao.i==u.ao.nByte );
 
-      if( pExpr->pSelect ){
-        /* Case 1:     expr IN (SELECT ...)
-        **
-        ** Generate code to write the results of the select into the temporary
-        ** table allocated and opened above.
-        */
-        SelectDest dest;
-        ExprList *pEList;
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  pOut->n = (int)u.ao.nByte;
+  pOut->flags = MEM_Blob | MEM_Dyn;
+  pOut->xDel = 0;
+  if( u.ao.nZero ){
+    pOut->u.nZero = u.ao.nZero;
+    pOut->flags |= MEM_Zero;
+  }
+  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever converted to text */
+  REGISTER_TRACE(pOp->p3, pOut);
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
+}
 
-        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
-        dest.affinity = (int)affinity;
-        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
-        if( sqlite3Select(pParse, pExpr->pSelect, &dest, 0, 0, 0, 0) ){
-          return;
-        }
-        pEList = pExpr->pSelect->pEList;
-        if( pEList && pEList->nExpr>0 ){ 
-          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
-              pEList->a[0].pExpr);
-        }
-      }else if( pExpr->pList ){
-        /* Case 2:     expr IN (exprlist)
-        **
-        ** For each expression, build an index key from the evaluation and
-        ** store it in the temporary table. If <expr> is a column, then use
-        ** that columns affinity when building index keys. If <expr> is not
-        ** a column, use numeric affinity.
-        */
-        int i;
-        ExprList *pList = pExpr->pList;
-        struct ExprList_item *pItem;
-        int r1, r2;
+/* Opcode: Count P1 P2 * * *
+**
+** Store the number of entries (an integer value) in the table or index 
+** opened by cursor P1 in register P2
+*/
+#ifndef SQLITE_OMIT_BTREECOUNT
+case OP_Count: {         /* out2-prerelease */
+#if 0  /* local variables moved into u.ap */
+  i64 nEntry;
+  BtCursor *pCrsr;
+#endif /* local variables moved into u.ap */
 
-        if( !affinity ){
-          affinity = SQLITE_AFF_NONE;
-        }
-        keyInfo.aColl[0] = pExpr->pLeft->pColl;
+  u.ap.pCrsr = p->apCsr[pOp->p1]->pCursor;
+  if( u.ap.pCrsr ){
+    rc = sqlite3BtreeCount(u.ap.pCrsr, &u.ap.nEntry);
+  }else{
+    u.ap.nEntry = 0;
+  }
+  pOut->flags = MEM_Int;
+  pOut->u.i = u.ap.nEntry;
+  break;
+}
+#endif
 
-        /* Loop through each expression in <exprlist>. */
-        r1 = sqlite3GetTempReg(pParse);
-        r2 = sqlite3GetTempReg(pParse);
-        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
-          Expr *pE2 = pItem->pExpr;
+/* Opcode: Savepoint P1 * * P4 *
+**
+** Open, release or rollback the savepoint named by parameter P4, depending
+** on the value of P1. To open a new savepoint, P1==0. To release (commit) an
+** existing savepoint, P1==1, or to rollback an existing savepoint P1==2.
+*/
+case OP_Savepoint: {
+#if 0  /* local variables moved into u.aq */
+  int p1;                         /* Value of P1 operand */
+  char *zName;                    /* Name of savepoint */
+  int nName;
+  Savepoint *pNew;
+  Savepoint *pSavepoint;
+  Savepoint *pTmp;
+  int iSavepoint;
+  int ii;
+#endif /* local variables moved into u.aq */
 
-          /* If the expression is not constant then we will need to
-          ** disable the test that was generated above that makes sure
-          ** this code only executes once.  Because for a non-constant
-          ** expression we need to rerun this code each time.
-          */
-          if( testAddr && !sqlite3ExprIsConstant(pE2) ){
-            sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
-            testAddr = 0;
-          }
+  u.aq.p1 = pOp->p1;
+  u.aq.zName = pOp->p4.z;
 
-          /* Evaluate the expression and insert it into the temp table */
-          pParse->disableColCache++;
-          sqlite3ExprCode(pParse, pE2, r1);
-          assert( pParse->disableColCache>0 );
-          pParse->disableColCache--;
-          sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1);
-          sqlite3ExprCacheAffinityChange(pParse, r1, 1);
-          sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
+  /* Assert that the u.aq.p1 parameter is valid. Also that if there is no open
+  ** transaction, then there cannot be any savepoints.
+  */
+  assert( db->pSavepoint==0 || db->autoCommit==0 );
+  assert( u.aq.p1==SAVEPOINT_BEGIN||u.aq.p1==SAVEPOINT_RELEASE||u.aq.p1==SAVEPOINT_ROLLBACK );
+  assert( db->pSavepoint || db->isTransactionSavepoint==0 );
+  assert( checkSavepointCount(db) );
+
+  if( u.aq.p1==SAVEPOINT_BEGIN ){
+    if( db->writeVdbeCnt>0 ){
+      /* A new savepoint cannot be created if there are active write
+      ** statements (i.e. open read/write incremental blob handles).
+      */
+      sqlite3SetString(&p->zErrMsg, db, "cannot open savepoint - "
+        "SQL statements in progress");
+      rc = SQLITE_BUSY;
+    }else{
+      u.aq.nName = sqlite3Strlen30(u.aq.zName);
+
+      /* Create a new savepoint structure. */
+      u.aq.pNew = sqlite3DbMallocRaw(db, sizeof(Savepoint)+u.aq.nName+1);
+      if( u.aq.pNew ){
+        u.aq.pNew->zName = (char *)&u.aq.pNew[1];
+        memcpy(u.aq.pNew->zName, u.aq.zName, u.aq.nName+1);
+
+        /* If there is no open transaction, then mark this as a special
+        ** "transaction savepoint". */
+        if( db->autoCommit ){
+          db->autoCommit = 0;
+          db->isTransactionSavepoint = 1;
+        }else{
+          db->nSavepoint++;
         }
-        sqlite3ReleaseTempReg(pParse, r1);
-        sqlite3ReleaseTempReg(pParse, r2);
+
+        /* Link the new savepoint into the database handle's list. */
+        u.aq.pNew->pNext = db->pSavepoint;
+        db->pSavepoint = u.aq.pNew;
+        u.aq.pNew->nDeferredCons = db->nDeferredCons;
       }
-      sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
-      break;
     }
-
-    case TK_EXISTS:
-    case TK_SELECT: {
-      /* This has to be a scalar SELECT.  Generate code to put the
-      ** value of this select in a memory cell and record the number
-      ** of the memory cell in iColumn.
+  }else{
+    u.aq.iSavepoint = 0;
+
+    /* Find the named savepoint. If there is no such savepoint, then an
+    ** an error is returned to the user.  */
+    for(
+      u.aq.pSavepoint = db->pSavepoint;
+      u.aq.pSavepoint && sqlite3StrICmp(u.aq.pSavepoint->zName, u.aq.zName);
+      u.aq.pSavepoint = u.aq.pSavepoint->pNext
+    ){
+      u.aq.iSavepoint++;
+    }
+    if( !u.aq.pSavepoint ){
+      sqlite3SetString(&p->zErrMsg, db, "no such savepoint: %s", u.aq.zName);
+      rc = SQLITE_ERROR;
+    }else if(
+        db->writeVdbeCnt>0 || (u.aq.p1==SAVEPOINT_ROLLBACK && db->activeVdbeCnt>1)
+    ){
+      /* It is not possible to release (commit) a savepoint if there are
+      ** active write statements. It is not possible to rollback a savepoint
+      ** if there are any active statements at all.
       */
-      static const Token one = { (u8*)"1", 0, 1 };
-      Select *pSel;
-      SelectDest dest;
+      sqlite3SetString(&p->zErrMsg, db,
+        "cannot %s savepoint - SQL statements in progress",
+        (u.aq.p1==SAVEPOINT_ROLLBACK ? "rollback": "release")
+      );
+      rc = SQLITE_BUSY;
+    }else{
 
-      pSel = pExpr->pSelect;
-      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
-      if( pExpr->op==TK_SELECT ){
-        dest.eDest = SRT_Mem;
-        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
-        VdbeComment((v, "Init subquery result"));
+      /* Determine whether or not this is a transaction savepoint. If so,
+      ** and this is a RELEASE command, then the current transaction
+      ** is committed.
+      */
+      int isTransaction = u.aq.pSavepoint->pNext==0 && db->isTransactionSavepoint;
+      if( isTransaction && u.aq.p1==SAVEPOINT_RELEASE ){
+        if( (rc = sqlite3VdbeCheckFk(p, 1))!=SQLITE_OK ){
+          goto vdbe_return;
+        }
+        db->autoCommit = 1;
+        if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
+          p->pc = pc;
+          db->autoCommit = 0;
+          p->rc = rc = SQLITE_BUSY;
+          goto vdbe_return;
+        }
+        db->isTransactionSavepoint = 0;
+        rc = p->rc;
       }else{
-        dest.eDest = SRT_Exists;
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
-        VdbeComment((v, "Init EXISTS result"));
+        u.aq.iSavepoint = db->nSavepoint - u.aq.iSavepoint - 1;
+        for(u.aq.ii=0; u.aq.ii<db->nDb; u.aq.ii++){
+          rc = sqlite3BtreeSavepoint(db->aDb[u.aq.ii].pBt, u.aq.p1, u.aq.iSavepoint);
+          if( rc!=SQLITE_OK ){
+            goto abort_due_to_error;
+          }
+        }
+        if( u.aq.p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
+          sqlite3ExpirePreparedStatements(db);
+          sqlite3ResetInternalSchema(db, 0);
+        }
       }
-      sqlite3ExprDelete(pSel->pLimit);
-      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
-      if( sqlite3Select(pParse, pSel, &dest, 0, 0, 0, 0) ){
-        return;
+
+      /* Regardless of whether this is a RELEASE or ROLLBACK, destroy all
+      ** savepoints nested inside of the savepoint being operated on. */
+      while( db->pSavepoint!=u.aq.pSavepoint ){
+        u.aq.pTmp = db->pSavepoint;
+        db->pSavepoint = u.aq.pTmp->pNext;
+        sqlite3DbFree(db, u.aq.pTmp);
+        db->nSavepoint--;
+      }
+
+      /* If it is a RELEASE, then destroy the savepoint being operated on
+      ** too. If it is a ROLLBACK TO, then set the number of deferred
+      ** constraint violations present in the database to the value stored
+      ** when the savepoint was created.  */
+      if( u.aq.p1==SAVEPOINT_RELEASE ){
+        assert( u.aq.pSavepoint==db->pSavepoint );
+        db->pSavepoint = u.aq.pSavepoint->pNext;
+        sqlite3DbFree(db, u.aq.pSavepoint);
+        if( !isTransaction ){
+          db->nSavepoint--;
+        }
+      }else{
+        db->nDeferredCons = u.aq.pSavepoint->nDeferredCons;
       }
-      pExpr->iColumn = dest.iParm;
-      break;
     }
   }
 
-  if( testAddr ){
-    sqlite3VdbeJumpHere(v, testAddr-1);
-  }
-
-  return;
-}
-#endif /* SQLITE_OMIT_SUBQUERY */
-
-/*
-** Duplicate an 8-byte value
-*/
-static char *dup8bytes(Vdbe *v, const char *in){
-  char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
-  if( out ){
-    memcpy(out, in, 8);
-  }
-  return out;
+  break;
 }
 
-/*
-** Generate an instruction that will put the floating point
-** value described by z[0..n-1] into register iMem.
+/* Opcode: AutoCommit P1 P2 * * *
 **
-** The z[] string will probably not be zero-terminated.  But the 
-** z[n] character is guaranteed to be something that does not look
-** like the continuation of the number.
+** Set the database auto-commit flag to P1 (1 or 0). If P2 is true, roll
+** back any currently active btree transactions. If there are any active
+** VMs (apart from this one), then a ROLLBACK fails.  A COMMIT fails if
+** there are active writing VMs or active VMs that use shared cache.
+**
+** This instruction causes the VM to halt.
 */
-static void codeReal(Vdbe *v, const char *z, int n, int negateFlag, int iMem){
-  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
-  if( z ){
-    double value;
-    char *zV;
-    assert( !isdigit(z[n]) );
-    sqlite3AtoF(z, &value);
-    if( sqlite3IsNaN(value) ){
-      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem);
+case OP_AutoCommit: {
+#if 0  /* local variables moved into u.ar */
+  int desiredAutoCommit;
+  int iRollback;
+  int turnOnAC;
+#endif /* local variables moved into u.ar */
+
+  u.ar.desiredAutoCommit = pOp->p1;
+  u.ar.iRollback = pOp->p2;
+  u.ar.turnOnAC = u.ar.desiredAutoCommit && !db->autoCommit;
+  assert( u.ar.desiredAutoCommit==1 || u.ar.desiredAutoCommit==0 );
+  assert( u.ar.desiredAutoCommit==1 || u.ar.iRollback==0 );
+  assert( db->activeVdbeCnt>0 );  /* At least this one VM is active */
+
+  if( u.ar.turnOnAC && u.ar.iRollback && db->activeVdbeCnt>1 ){
+    /* If this instruction implements a ROLLBACK and other VMs are
+    ** still running, and a transaction is active, return an error indicating
+    ** that the other VMs must complete first.
+    */
+    sqlite3SetString(&p->zErrMsg, db, "cannot rollback transaction - "
+        "SQL statements in progress");
+    rc = SQLITE_BUSY;
+  }else if( u.ar.turnOnAC && !u.ar.iRollback && db->writeVdbeCnt>0 ){
+    /* If this instruction implements a COMMIT and other VMs are writing
+    ** return an error indicating that the other VMs must complete first.
+    */
+    sqlite3SetString(&p->zErrMsg, db, "cannot commit transaction - "
+        "SQL statements in progress");
+    rc = SQLITE_BUSY;
+  }else if( u.ar.desiredAutoCommit!=db->autoCommit ){
+    if( u.ar.iRollback ){
+      assert( u.ar.desiredAutoCommit==1 );
+      sqlite3RollbackAll(db);
+      db->autoCommit = 1;
+    }else if( (rc = sqlite3VdbeCheckFk(p, 1))!=SQLITE_OK ){
+      goto vdbe_return;
     }else{
-      if( negateFlag ) value = -value;
-      zV = dup8bytes(v, (char*)&value);
-      sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
+      db->autoCommit = (u8)u.ar.desiredAutoCommit;
+      if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
+        p->pc = pc;
+        db->autoCommit = (u8)(1-u.ar.desiredAutoCommit);
+        p->rc = rc = SQLITE_BUSY;
+        goto vdbe_return;
+      }
     }
-  }
-}
-
-
-/*
-** Generate an instruction that will put the integer describe by
-** text z[0..n-1] into register iMem.
-**
-** The z[] string will probably not be zero-terminated.  But the 
-** z[n] character is guaranteed to be something that does not look
-** like the continuation of the number.
-*/
-static void codeInteger(Vdbe *v, const char *z, int n, int negFlag, int iMem){
-  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
-  if( z ){
-    int i;
-    assert( !isdigit(z[n]) );
-    if( sqlite3GetInt32(z, &i) ){
-      if( negFlag ) i = -i;
-      sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
-    }else if( sqlite3FitsIn64Bits(z, negFlag) ){
-      i64 value;
-      char *zV;
-      sqlite3Atoi64(z, &value);
-      if( negFlag ) value = -value;
-      zV = dup8bytes(v, (char*)&value);
-      sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
+    assert( db->nStatement==0 );
+    sqlite3CloseSavepoints(db);
+    if( p->rc==SQLITE_OK ){
+      rc = SQLITE_DONE;
     }else{
-      codeReal(v, z, n, negFlag, iMem);
+      rc = SQLITE_ERROR;
     }
+    goto vdbe_return;
+  }else{
+    sqlite3SetString(&p->zErrMsg, db,
+        (!u.ar.desiredAutoCommit)?"cannot start a transaction within a transaction":(
+        (u.ar.iRollback)?"cannot rollback - no transaction is active":
+                   "cannot commit - no transaction is active"));
+
+    rc = SQLITE_ERROR;
   }
+  break;
 }
 
-
-/*
-** Generate code that will extract the iColumn-th column from
-** table pTab and store the column value in a register.  An effort
-** is made to store the column value in register iReg, but this is
-** not guaranteed.  The location of the column value is returned.
+/* Opcode: Transaction P1 P2 * * *
 **
-** There must be an open cursor to pTab in iTable when this routine
-** is called.  If iColumn<0 then code is generated that extracts the rowid.
+** Begin a transaction.  The transaction ends when a Commit or Rollback
+** opcode is encountered.  Depending on the ON CONFLICT setting, the
+** transaction might also be rolled back if an error is encountered.
 **
-** This routine might attempt to reuse the value of the column that
-** has already been loaded into a register.  The value will always
-** be used if it has not undergone any affinity changes.  But if
-** an affinity change has occurred, then the cached value will only be
-** used if allowAffChng is true.
+** P1 is the index of the database file on which the transaction is
+** started.  Index 0 is the main database file and index 1 is the
+** file used for temporary tables.  Indices of 2 or more are used for
+** attached databases.
+**
+** If P2 is non-zero, then a write-transaction is started.  A RESERVED lock is
+** obtained on the database file when a write-transaction is started.  No
+** other process can start another write transaction while this transaction is
+** underway.  Starting a write transaction also creates a rollback journal. A
+** write transaction must be started before any changes can be made to the
+** database.  If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
+** on the file.
+**
+** If a write-transaction is started and the Vdbe.usesStmtJournal flag is
+** true (this flag is set if the Vdbe may modify more than one row and may
+** throw an ABORT exception), a statement transaction may also be opened.
+** More specifically, a statement transaction is opened iff the database
+** connection is currently not in autocommit mode, or if there are other
+** active statements. A statement transaction allows the affects of this
+** VDBE to be rolled back after an error without having to roll back the
+** entire transaction. If no error is encountered, the statement transaction
+** will automatically commit when the VDBE halts.
+**
+** If P2 is zero, then a read-lock is obtained on the database file.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(
-  Parse *pParse,   /* Parsing and code generating context */
-  Table *pTab,     /* Description of the table we are reading from */
-  int iColumn,     /* Index of the table column */
-  int iTable,      /* The cursor pointing to the table */
-  int iReg,        /* Store results here */
-  int allowAffChng /* True if prior affinity changes are OK */
-){
-  Vdbe *v = pParse->pVdbe;
-  int i;
-  struct yColCache *p;
+case OP_Transaction: {
+#if 0  /* local variables moved into u.as */
+  Btree *pBt;
+#endif /* local variables moved into u.as */
 
-  for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){
-    if( p->iTable==iTable && p->iColumn==iColumn
-           && (!p->affChange || allowAffChng) ){
-#if 0
-      sqlite3VdbeAddOp0(v, OP_Noop);
-      VdbeComment((v, "OPT: tab%d.col%d -> r%d", iTable, iColumn, p->iReg));
-#endif
-      return p->iReg;
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
+  u.as.pBt = db->aDb[pOp->p1].pBt;
+
+  if( u.as.pBt ){
+    rc = sqlite3BtreeBeginTrans(u.as.pBt, pOp->p2);
+    if( rc==SQLITE_BUSY ){
+      p->pc = pc;
+      p->rc = rc = SQLITE_BUSY;
+      goto vdbe_return;
     }
-  }  
-  assert( v!=0 );
-  if( iColumn<0 ){
-    int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
-    sqlite3VdbeAddOp2(v, op, iTable, iReg);
-  }else if( pTab==0 ){
-    sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
-  }else{
-    int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
-    sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
-    sqlite3ColumnDefault(v, pTab, iColumn);
-#ifndef SQLITE_OMIT_FLOATING_POINT
-    if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
-      sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
+    if( rc!=SQLITE_OK ){
+      goto abort_due_to_error;
     }
-#endif
-  }
-  if( pParse->disableColCache==0 ){
-    i = pParse->iColCache;
-    p = &pParse->aColCache[i];
-    p->iTable = iTable;
-    p->iColumn = iColumn;
-    p->iReg = iReg;
-    p->affChange = 0;
-    i++;
-    if( i>=ArraySize(pParse->aColCache) ) i = 0;
-    if( i>pParse->nColCache ) pParse->nColCache = i;
-    pParse->iColCache = i;
-  }
-  return iReg;
-}
 
-/*
-** Clear all column cache entries associated with the vdbe
-** cursor with cursor number iTable.
-*/
-SQLITE_PRIVATE void sqlite3ExprClearColumnCache(Parse *pParse, int iTable){
-  if( iTable<0 ){
-    pParse->nColCache = 0;
-    pParse->iColCache = 0;
-  }else{
-    int i;
-    for(i=0; i<pParse->nColCache; i++){
-      if( pParse->aColCache[i].iTable==iTable ){
-        testcase( i==pParse->nColCache-1 );
-        pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
-        pParse->iColCache = pParse->nColCache;
+    if( pOp->p2 && p->usesStmtJournal
+     && (db->autoCommit==0 || db->activeVdbeCnt>1)
+    ){
+      assert( sqlite3BtreeIsInTrans(u.as.pBt) );
+      if( p->iStatement==0 ){
+        assert( db->nStatement>=0 && db->nSavepoint>=0 );
+        db->nStatement++;
+        p->iStatement = db->nSavepoint + db->nStatement;
       }
-    }
-  }
-}
+      rc = sqlite3BtreeBeginStmt(u.as.pBt, p->iStatement);
 
-/*
-** Record the fact that an affinity change has occurred on iCount
-** registers starting with iStart.
-*/
-SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
-  int iEnd = iStart + iCount - 1;
-  int i;
-  for(i=0; i<pParse->nColCache; i++){
-    int r = pParse->aColCache[i].iReg;
-    if( r>=iStart && r<=iEnd ){
-      pParse->aColCache[i].affChange = 1;
+      /* Store the current value of the database handles deferred constraint
+      ** counter. If the statement transaction needs to be rolled back,
+      ** the value of this counter needs to be restored too.  */
+      p->nStmtDefCons = db->nDeferredCons;
     }
   }
+  break;
 }
 
-/*
-** Generate code to moves content from one register to another.
-** Keep the column cache up-to-date.
+/* Opcode: ReadCookie P1 P2 P3 * *
+**
+** Read cookie number P3 from database P1 and write it into register P2.
+** P3==1 is the schema version.  P3==2 is the database format.
+** P3==3 is the recommended pager cache size, and so forth.  P1==0 is
+** the main database file and P1==1 is the database file used to store
+** temporary tables.
+**
+** There must be a read-lock on the database (either a transaction
+** must be started or there must be an open cursor) before
+** executing this instruction.
 */
-SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo){
-  int i;
-  if( iFrom==iTo ) return;
-  sqlite3VdbeAddOp2(pParse->pVdbe, OP_Move, iFrom, iTo);
-  for(i=0; i<pParse->nColCache; i++){
-    if( pParse->aColCache[i].iReg==iFrom ){
-      pParse->aColCache[i].iReg = iTo;
-    }
-  }
-}
+case OP_ReadCookie: {               /* out2-prerelease */
+#if 0  /* local variables moved into u.at */
+  int iMeta;
+  int iDb;
+  int iCookie;
+#endif /* local variables moved into u.at */
 
-/*
-** Return true if any register in the range iFrom..iTo (inclusive)
-** is used as part of the column cache.
-*/
-static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
-  int i;
-  for(i=0; i<pParse->nColCache; i++){
-    int r = pParse->aColCache[i].iReg;
-    if( r>=iFrom && r<=iTo ) return 1;
-  }
-  return 0;
+  u.at.iDb = pOp->p1;
+  u.at.iCookie = pOp->p3;
+  assert( pOp->p3<SQLITE_N_BTREE_META );
+  assert( u.at.iDb>=0 && u.at.iDb<db->nDb );
+  assert( db->aDb[u.at.iDb].pBt!=0 );
+  assert( (p->btreeMask & (1<<u.at.iDb))!=0 );
+
+  sqlite3BtreeGetMeta(db->aDb[u.at.iDb].pBt, u.at.iCookie, (u32 *)&u.at.iMeta);
+  pOut->u.i = u.at.iMeta;
+  MemSetTypeFlag(pOut, MEM_Int);
+  break;
 }
 
-/*
-** Theres is a value in register iCurrent.  We ultimately want
-** the value to be in register iTarget.  It might be that
-** iCurrent and iTarget are the same register.
+/* Opcode: SetCookie P1 P2 P3 * *
 **
-** We are going to modify the value, so we need to make sure it
-** is not a cached register.  If iCurrent is a cached register,
-** then try to move the value over to iTarget.  If iTarget is a
-** cached register, then clear the corresponding cache line.
+** Write the content of register P3 (interpreted as an integer)
+** into cookie number P2 of database P1.  P2==1 is the schema version.  
+** P2==2 is the database format. P2==3 is the recommended pager cache 
+** size, and so forth.  P1==0 is the main database file and P1==1 is the 
+** database file used to store temporary tables.
 **
-** Return the register that the value ends up in.
+** A transaction must be started before executing this opcode.
 */
-SQLITE_PRIVATE int sqlite3ExprWritableRegister(Parse *pParse, int iCurrent, int iTarget){
-  int i;
-  assert( pParse->pVdbe!=0 );
-  if( !usedAsColumnCache(pParse, iCurrent, iCurrent) ){
-    return iCurrent;
-  }
-  if( iCurrent!=iTarget ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, iCurrent, iTarget);
+case OP_SetCookie: {       /* in3 */
+#if 0  /* local variables moved into u.au */
+  Db *pDb;
+#endif /* local variables moved into u.au */
+  assert( pOp->p2<SQLITE_N_BTREE_META );
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
+  u.au.pDb = &db->aDb[pOp->p1];
+  assert( u.au.pDb->pBt!=0 );
+  sqlite3VdbeMemIntegerify(pIn3);
+  /* See note about index shifting on OP_ReadCookie */
+  rc = sqlite3BtreeUpdateMeta(u.au.pDb->pBt, pOp->p2, (int)pIn3->u.i);
+  if( pOp->p2==BTREE_SCHEMA_VERSION ){
+    /* When the schema cookie changes, record the new cookie internally */
+    u.au.pDb->pSchema->schema_cookie = (int)pIn3->u.i;
+    db->flags |= SQLITE_InternChanges;
+  }else if( pOp->p2==BTREE_FILE_FORMAT ){
+    /* Record changes in the file format */
+    u.au.pDb->pSchema->file_format = (u8)pIn3->u.i;
   }
-  for(i=0; i<pParse->nColCache; i++){
-    if( pParse->aColCache[i].iReg==iTarget ){
-      pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
-      pParse->iColCache = pParse->nColCache;
-    }
+  if( pOp->p1==1 ){
+    /* Invalidate all prepared statements whenever the TEMP database
+    ** schema is changed.  Ticket #1644 */
+    sqlite3ExpirePreparedStatements(db);
   }
-  return iTarget;
+  break;
 }
 
-/*
-** If the last instruction coded is an ephemeral copy of any of
-** the registers in the nReg registers beginning with iReg, then
-** convert the last instruction from OP_SCopy to OP_Copy.
+/* Opcode: VerifyCookie P1 P2 *
+**
+** Check the value of global database parameter number 0 (the
+** schema version) and make sure it is equal to P2.  
+** P1 is the database number which is 0 for the main database file
+** and 1 for the file holding temporary tables and some higher number
+** for auxiliary databases.
+**
+** The cookie changes its value whenever the database schema changes.
+** This operation is used to detect when that the cookie has changed
+** and that the current process needs to reread the schema.
+**
+** Either a transaction needs to have been started or an OP_Open needs
+** to be executed (to establish a read lock) before this opcode is
+** invoked.
 */
-SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
-  int addr;
-  VdbeOp *pOp;
-  Vdbe *v;
+case OP_VerifyCookie: {
+#if 0  /* local variables moved into u.av */
+  int iMeta;
+  Btree *pBt;
+#endif /* local variables moved into u.av */
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
+  u.av.pBt = db->aDb[pOp->p1].pBt;
+  if( u.av.pBt ){
+    sqlite3BtreeGetMeta(u.av.pBt, BTREE_SCHEMA_VERSION, (u32 *)&u.av.iMeta);
+  }else{
+    u.av.iMeta = 0;
+  }
+  if( u.av.iMeta!=pOp->p2 ){
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
+    /* If the schema-cookie from the database file matches the cookie
+    ** stored with the in-memory representation of the schema, do
+    ** not reload the schema from the database file.
+    **
+    ** If virtual-tables are in use, this is not just an optimization.
+    ** Often, v-tables store their data in other SQLite tables, which
+    ** are queried from within xNext() and other v-table methods using
+    ** prepared queries. If such a query is out-of-date, we do not want to
+    ** discard the database schema, as the user code implementing the
+    ** v-table would have to be ready for the sqlite3_vtab structure itself
+    ** to be invalidated whenever sqlite3_step() is called from within
+    ** a v-table method.
+    */
+    if( db->aDb[pOp->p1].pSchema->schema_cookie!=u.av.iMeta ){
+      sqlite3ResetInternalSchema(db, pOp->p1);
+    }
 
-  v = pParse->pVdbe;
-  addr = sqlite3VdbeCurrentAddr(v);
-  pOp = sqlite3VdbeGetOp(v, addr-1);
-  assert( pOp || pParse->db->mallocFailed );
-  if( pOp && pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
-    pOp->opcode = OP_Copy;
+    sqlite3ExpirePreparedStatements(db);
+    rc = SQLITE_SCHEMA;
   }
+  break;
 }
 
-/*
-** Generate code into the current Vdbe to evaluate the given
-** expression.  Attempt to store the results in register "target".
-** Return the register where results are stored.
+/* Opcode: OpenRead P1 P2 P3 P4 P5
 **
-** With this routine, there is no guaranteed that results will
-** be stored in target.  The result might be stored in some other
-** register if it is convenient to do so.  The calling function
-** must check the return code and move the results to the desired
-** register.
+** Open a read-only cursor for the database table whose root page is
+** P2 in a database file.  The database file is determined by P3. 
+** P3==0 means the main database, P3==1 means the database used for 
+** temporary tables, and P3>1 means used the corresponding attached
+** database.  Give the new cursor an identifier of P1.  The P1
+** values need not be contiguous but all P1 values should be small integers.
+** It is an error for P1 to be negative.
+**
+** If P5!=0 then use the content of register P2 as the root page, not
+** the value of P2 itself.
+**
+** There will be a read lock on the database whenever there is an
+** open cursor.  If the database was unlocked prior to this instruction
+** then a read lock is acquired as part of this instruction.  A read
+** lock allows other processes to read the database but prohibits
+** any other process from modifying the database.  The read lock is
+** released when all cursors are closed.  If this instruction attempts
+** to get a read lock but fails, the script terminates with an
+** SQLITE_BUSY error code.
+**
+** The P4 value may be either an integer (P4_INT32) or a pointer to
+** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo 
+** structure, then said structure defines the content and collating 
+** sequence of the index being opened. Otherwise, if P4 is an integer 
+** value, it is set to the number of columns in the table.
+**
+** See also OpenWrite.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
-  Vdbe *v = pParse->pVdbe;  /* The VM under construction */
-  int op;                   /* The opcode being coded */
-  int inReg = target;       /* Results stored in register inReg */
-  int regFree1 = 0;         /* If non-zero free this temporary register */
-  int regFree2 = 0;         /* If non-zero free this temporary register */
-  int r1, r2, r3, r4;       /* Various register numbers */
-
-  assert( v!=0 || pParse->db->mallocFailed );
-  assert( target>0 && target<=pParse->nMem );
-  if( v==0 ) return 0;
-
-  if( pExpr==0 ){
-    op = TK_NULL;
+/* Opcode: OpenWrite P1 P2 P3 P4 P5
+**
+** Open a read/write cursor named P1 on the table or index whose root
+** page is P2.  Or if P5!=0 use the content of register P2 to find the
+** root page.
+**
+** The P4 value may be either an integer (P4_INT32) or a pointer to
+** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo 
+** structure, then said structure defines the content and collating 
+** sequence of the index being opened. Otherwise, if P4 is an integer 
+** value, it is set to the number of columns in the table, or to the
+** largest index of any column of the table that is actually used.
+**
+** This instruction works just like OpenRead except that it opens the cursor
+** in read/write mode.  For a given table, there can be one or more read-only
+** cursors or a single read/write cursor but not both.
+**
+** See also OpenRead.
+*/
+case OP_OpenRead:
+case OP_OpenWrite: {
+#if 0  /* local variables moved into u.aw */
+  int nField;
+  KeyInfo *pKeyInfo;
+  int p2;
+  int iDb;
+  int wrFlag;
+  Btree *pX;
+  VdbeCursor *pCur;
+  Db *pDb;
+#endif /* local variables moved into u.aw */
+
+  u.aw.nField = 0;
+  u.aw.pKeyInfo = 0;
+  u.aw.p2 = pOp->p2;
+  u.aw.iDb = pOp->p3;
+  assert( u.aw.iDb>=0 && u.aw.iDb<db->nDb );
+  assert( (p->btreeMask & (1<<u.aw.iDb))!=0 );
+  u.aw.pDb = &db->aDb[u.aw.iDb];
+  u.aw.pX = u.aw.pDb->pBt;
+  assert( u.aw.pX!=0 );
+  if( pOp->opcode==OP_OpenWrite ){
+    u.aw.wrFlag = 1;
+    if( u.aw.pDb->pSchema->file_format < p->minWriteFileFormat ){
+      p->minWriteFileFormat = u.aw.pDb->pSchema->file_format;
+    }
   }else{
-    op = pExpr->op;
+    u.aw.wrFlag = 0;
   }
-  switch( op ){
-    case TK_AGG_COLUMN: {
-      AggInfo *pAggInfo = pExpr->pAggInfo;
-      struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
-      if( !pAggInfo->directMode ){
-        assert( pCol->iMem>0 );
-        inReg = pCol->iMem;
-        break;
-      }else if( pAggInfo->useSortingIdx ){
-        sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
-                              pCol->iSorterColumn, target);
-        break;
-      }
-      /* Otherwise, fall thru into the TK_COLUMN case */
-    }
-    case TK_COLUMN: {
-      if( pExpr->iTable<0 ){
-        /* This only happens when coding check constraints */
-        assert( pParse->ckBase>0 );
-        inReg = pExpr->iColumn + pParse->ckBase;
-      }else{
-        testcase( (pExpr->flags & EP_AnyAff)!=0 );
-        inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
-                                 pExpr->iColumn, pExpr->iTable, target,
-                                 pExpr->flags & EP_AnyAff);
-      }
-      break;
-    }
-    case TK_INTEGER: {
-      codeInteger(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
-      break;
-    }
-    case TK_FLOAT: {
-      codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
-      break;
-    }
-    case TK_STRING: {
-      sqlite3DequoteExpr(pParse->db, pExpr);
-      sqlite3VdbeAddOp4(v,OP_String8, 0, target, 0,
-                        (char*)pExpr->token.z, pExpr->token.n);
-      break;
-    }
-    case TK_NULL: {
-      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
-      break;
-    }
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-    case TK_BLOB: {
-      int n;
-      const char *z;
-      char *zBlob;
-      assert( pExpr->token.n>=3 );
-      assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
-      assert( pExpr->token.z[1]=='\'' );
-      assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
-      n = pExpr->token.n - 3;
-      z = (char*)pExpr->token.z + 2;
-      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
-      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
-      break;
+  if( pOp->p5 ){
+    assert( u.aw.p2>0 );
+    assert( u.aw.p2<=p->nMem );
+    pIn2 = &p->aMem[u.aw.p2];
+    sqlite3VdbeMemIntegerify(pIn2);
+    u.aw.p2 = (int)pIn2->u.i;
+    /* The u.aw.p2 value always comes from a prior OP_CreateTable opcode and
+    ** that opcode will always set the u.aw.p2 value to 2 or more or else fail.
+    ** If there were a failure, the prepared statement would have halted
+    ** before reaching this instruction. */
+    if( NEVER(u.aw.p2<2) ) {
+      rc = SQLITE_CORRUPT_BKPT;
+      goto abort_due_to_error;
     }
-#endif
-    case TK_VARIABLE: {
-      sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iTable, target);
-      if( pExpr->token.n>1 ){
-        sqlite3VdbeChangeP4(v, -1, (char*)pExpr->token.z, pExpr->token.n);
+  }
+  if( pOp->p4type==P4_KEYINFO ){
+    u.aw.pKeyInfo = pOp->p4.pKeyInfo;
+    u.aw.pKeyInfo->enc = ENC(p->db);
+    u.aw.nField = u.aw.pKeyInfo->nField+1;
+  }else if( pOp->p4type==P4_INT32 ){
+    u.aw.nField = pOp->p4.i;
+  }
+  assert( pOp->p1>=0 );
+  u.aw.pCur = allocateCursor(p, pOp->p1, u.aw.nField, u.aw.iDb, 1);
+  if( u.aw.pCur==0 ) goto no_mem;
+  u.aw.pCur->nullRow = 1;
+  rc = sqlite3BtreeCursor(u.aw.pX, u.aw.p2, u.aw.wrFlag, u.aw.pKeyInfo, u.aw.pCur->pCursor);
+  u.aw.pCur->pKeyInfo = u.aw.pKeyInfo;
+
+  /* Since it performs no memory allocation or IO, the only values that
+  ** sqlite3BtreeCursor() may return are SQLITE_EMPTY and SQLITE_OK.
+  ** SQLITE_EMPTY is only returned when attempting to open the table
+  ** rooted at page 1 of a zero-byte database.  */
+  assert( rc==SQLITE_EMPTY || rc==SQLITE_OK );
+  if( rc==SQLITE_EMPTY ){
+    u.aw.pCur->pCursor = 0;
+    rc = SQLITE_OK;
+  }
+
+  /* Set the VdbeCursor.isTable and isIndex variables. Previous versions of
+  ** SQLite used to check if the root-page flags were sane at this point
+  ** and report database corruption if they were not, but this check has
+  ** since moved into the btree layer.  */
+  u.aw.pCur->isTable = pOp->p4type!=P4_KEYINFO;
+  u.aw.pCur->isIndex = !u.aw.pCur->isTable;
+  break;
+}
+
+/* Opcode: OpenEphemeral P1 P2 * P4 *
+**
+** Open a new cursor P1 to a transient table.
+** The cursor is always opened read/write even if 
+** the main database is read-only.  The transient or virtual
+** table is deleted automatically when the cursor is closed.
+**
+** P2 is the number of columns in the virtual table.
+** The cursor points to a BTree table if P4==0 and to a BTree index
+** if P4 is not 0.  If P4 is not NULL, it points to a KeyInfo structure
+** that defines the format of keys in the index.
+**
+** This opcode was once called OpenTemp.  But that created
+** confusion because the term "temp table", might refer either
+** to a TEMP table at the SQL level, or to a table opened by
+** this opcode.  Then this opcode was call OpenVirtual.  But
+** that created confusion with the whole virtual-table idea.
+*/
+case OP_OpenEphemeral: {
+#if 0  /* local variables moved into u.ax */
+  VdbeCursor *pCx;
+#endif /* local variables moved into u.ax */
+  static const int openFlags =
+      SQLITE_OPEN_READWRITE |
+      SQLITE_OPEN_CREATE |
+      SQLITE_OPEN_EXCLUSIVE |
+      SQLITE_OPEN_DELETEONCLOSE |
+      SQLITE_OPEN_TRANSIENT_DB;
+
+  assert( pOp->p1>=0 );
+  u.ax.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
+  if( u.ax.pCx==0 ) goto no_mem;
+  u.ax.pCx->nullRow = 1;
+  rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
+                           &u.ax.pCx->pBt);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3BtreeBeginTrans(u.ax.pCx->pBt, 1);
+  }
+  if( rc==SQLITE_OK ){
+    /* If a transient index is required, create it by calling
+    ** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
+    ** opening it. If a transient table is required, just use the
+    ** automatically created table with root-page 1 (an INTKEY table).
+    */
+    if( pOp->p4.pKeyInfo ){
+      int pgno;
+      assert( pOp->p4type==P4_KEYINFO );
+      rc = sqlite3BtreeCreateTable(u.ax.pCx->pBt, &pgno, BTREE_ZERODATA);
+      if( rc==SQLITE_OK ){
+        assert( pgno==MASTER_ROOT+1 );
+        rc = sqlite3BtreeCursor(u.ax.pCx->pBt, pgno, 1,
+                                (KeyInfo*)pOp->p4.z, u.ax.pCx->pCursor);
+        u.ax.pCx->pKeyInfo = pOp->p4.pKeyInfo;
+        u.ax.pCx->pKeyInfo->enc = ENC(p->db);
       }
-      break;
-    }
-    case TK_REGISTER: {
-      inReg = pExpr->iTable;
-      break;
-    }
-#ifndef SQLITE_OMIT_CAST
-    case TK_CAST: {
-      /* Expressions of the form:   CAST(pLeft AS token) */
-      int aff, to_op;
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-      aff = sqlite3AffinityType(&pExpr->token);
-      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
-      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
-      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
-      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
-      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
-      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
-      testcase( to_op==OP_ToText );
-      testcase( to_op==OP_ToBlob );
-      testcase( to_op==OP_ToNumeric );
-      testcase( to_op==OP_ToInt );
-      testcase( to_op==OP_ToReal );
-      sqlite3VdbeAddOp1(v, to_op, inReg);
-      testcase( usedAsColumnCache(pParse, inReg, inReg) );
-      sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
-      break;
-    }
-#endif /* SQLITE_OMIT_CAST */
-    case TK_LT:
-    case TK_LE:
-    case TK_GT:
-    case TK_GE:
-    case TK_NE:
-    case TK_EQ: {
-      assert( TK_LT==OP_Lt );
-      assert( TK_LE==OP_Le );
-      assert( TK_GT==OP_Gt );
-      assert( TK_GE==OP_Ge );
-      assert( TK_EQ==OP_Eq );
-      assert( TK_NE==OP_Ne );
-      testcase( op==TK_LT );
-      testcase( op==TK_LE );
-      testcase( op==TK_GT );
-      testcase( op==TK_GE );
-      testcase( op==TK_EQ );
-      testcase( op==TK_NE );
-      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
-                                  pExpr->pRight, &r2, &regFree2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, inReg, SQLITE_STOREP2);
-      testcase( regFree1==0 );
-      testcase( regFree2==0 );
-      break;
-    }
-    case TK_AND:
-    case TK_OR:
-    case TK_PLUS:
-    case TK_STAR:
-    case TK_MINUS:
-    case TK_REM:
-    case TK_BITAND:
-    case TK_BITOR:
-    case TK_SLASH:
-    case TK_LSHIFT:
-    case TK_RSHIFT: 
-    case TK_CONCAT: {
-      assert( TK_AND==OP_And );
-      assert( TK_OR==OP_Or );
-      assert( TK_PLUS==OP_Add );
-      assert( TK_MINUS==OP_Subtract );
-      assert( TK_REM==OP_Remainder );
-      assert( TK_BITAND==OP_BitAnd );
-      assert( TK_BITOR==OP_BitOr );
-      assert( TK_SLASH==OP_Divide );
-      assert( TK_LSHIFT==OP_ShiftLeft );
-      assert( TK_RSHIFT==OP_ShiftRight );
-      assert( TK_CONCAT==OP_Concat );
-      testcase( op==TK_AND );
-      testcase( op==TK_OR );
-      testcase( op==TK_PLUS );
-      testcase( op==TK_MINUS );
-      testcase( op==TK_REM );
-      testcase( op==TK_BITAND );
-      testcase( op==TK_BITOR );
-      testcase( op==TK_SLASH );
-      testcase( op==TK_LSHIFT );
-      testcase( op==TK_RSHIFT );
-      testcase( op==TK_CONCAT );
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
-      sqlite3VdbeAddOp3(v, op, r2, r1, target);
-      testcase( regFree1==0 );
-      testcase( regFree2==0 );
-      break;
+      u.ax.pCx->isTable = 0;
+    }else{
+      rc = sqlite3BtreeCursor(u.ax.pCx->pBt, MASTER_ROOT, 1, 0, u.ax.pCx->pCursor);
+      u.ax.pCx->isTable = 1;
     }
-    case TK_UMINUS: {
-      Expr *pLeft = pExpr->pLeft;
-      assert( pLeft );
-      if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){
-        Token *p = &pLeft->token;
-        if( pLeft->op==TK_FLOAT ){
-          codeReal(v, (char*)p->z, p->n, 1, target);
+  }
+  u.ax.pCx->isIndex = !u.ax.pCx->isTable;
+  break;
+}
+
+/* Opcode: OpenPseudo P1 P2 P3 * *
+**
+** Open a new cursor that points to a fake table that contains a single
+** row of data.  The content of that one row in the content of memory
+** register P2.  In other words, cursor P1 becomes an alias for the 
+** MEM_Blob content contained in register P2.
+**
+** A pseudo-table created by this opcode is used to hold the a single
+** row output from the sorter so that the row can be decomposed into
+** individual columns using the OP_Column opcode.  The OP_Column opcode
+** is the only cursor opcode that works with a pseudo-table.
+**
+** P3 is the number of fields in the records that will be stored by
+** the pseudo-table.
+*/
+case OP_OpenPseudo: {
+#if 0  /* local variables moved into u.ay */
+  VdbeCursor *pCx;
+#endif /* local variables moved into u.ay */
+
+  assert( pOp->p1>=0 );
+  u.ay.pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, 0);
+  if( u.ay.pCx==0 ) goto no_mem;
+  u.ay.pCx->nullRow = 1;
+  u.ay.pCx->pseudoTableReg = pOp->p2;
+  u.ay.pCx->isTable = 1;
+  u.ay.pCx->isIndex = 0;
+  break;
+}
+
+/* Opcode: Close P1 * * * *
+**
+** Close a cursor previously opened as P1.  If P1 is not
+** currently open, this instruction is a no-op.
+*/
+case OP_Close: {
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  sqlite3VdbeFreeCursor(p, p->apCsr[pOp->p1]);
+  p->apCsr[pOp->p1] = 0;
+  break;
+}
+
+/* Opcode: SeekGe P1 P2 P3 P4 *
+**
+** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
+** use the value in register P3 as the key.  If cursor P1 refers 
+** to an SQL index, then P3 is the first in an array of P4 registers 
+** that are used as an unpacked index key. 
+**
+** Reposition cursor P1 so that  it points to the smallest entry that 
+** is greater than or equal to the key value. If there are no records 
+** greater than or equal to the key and P2 is not zero, then jump to P2.
+**
+** See also: Found, NotFound, Distinct, SeekLt, SeekGt, SeekLe
+*/
+/* Opcode: SeekGt P1 P2 P3 P4 *
+**
+** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
+** use the value in register P3 as a key. If cursor P1 refers 
+** to an SQL index, then P3 is the first in an array of P4 registers 
+** that are used as an unpacked index key. 
+**
+** Reposition cursor P1 so that  it points to the smallest entry that 
+** is greater than the key value. If there are no records greater than 
+** the key and P2 is not zero, then jump to P2.
+**
+** See also: Found, NotFound, Distinct, SeekLt, SeekGe, SeekLe
+*/
+/* Opcode: SeekLt P1 P2 P3 P4 * 
+**
+** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
+** use the value in register P3 as a key. If cursor P1 refers 
+** to an SQL index, then P3 is the first in an array of P4 registers 
+** that are used as an unpacked index key. 
+**
+** Reposition cursor P1 so that  it points to the largest entry that 
+** is less than the key value. If there are no records less than 
+** the key and P2 is not zero, then jump to P2.
+**
+** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLe
+*/
+/* Opcode: SeekLe P1 P2 P3 P4 *
+**
+** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
+** use the value in register P3 as a key. If cursor P1 refers 
+** to an SQL index, then P3 is the first in an array of P4 registers 
+** that are used as an unpacked index key. 
+**
+** Reposition cursor P1 so that it points to the largest entry that 
+** is less than or equal to the key value. If there are no records 
+** less than or equal to the key and P2 is not zero, then jump to P2.
+**
+** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLt
+*/
+case OP_SeekLt:         /* jump, in3 */
+case OP_SeekLe:         /* jump, in3 */
+case OP_SeekGe:         /* jump, in3 */
+case OP_SeekGt: {       /* jump, in3 */
+#if 0  /* local variables moved into u.az */
+  int res;
+  int oc;
+  VdbeCursor *pC;
+  UnpackedRecord r;
+  int nField;
+  i64 iKey;      /* The rowid we are to seek to */
+#endif /* local variables moved into u.az */
+
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  assert( pOp->p2!=0 );
+  u.az.pC = p->apCsr[pOp->p1];
+  assert( u.az.pC!=0 );
+  assert( u.az.pC->pseudoTableReg==0 );
+  if( u.az.pC->pCursor!=0 ){
+    u.az.oc = pOp->opcode;
+    u.az.pC->nullRow = 0;
+    if( u.az.pC->isTable ){
+      /* The input value in P3 might be of any type: integer, real, string,
+      ** blob, or NULL.  But it needs to be an integer before we can do
+      ** the seek, so covert it. */
+      applyNumericAffinity(pIn3);
+      u.az.iKey = sqlite3VdbeIntValue(pIn3);
+      u.az.pC->rowidIsValid = 0;
+
+      /* If the P3 value could not be converted into an integer without
+      ** loss of information, then special processing is required... */
+      if( (pIn3->flags & MEM_Int)==0 ){
+        if( (pIn3->flags & MEM_Real)==0 ){
+          /* If the P3 value cannot be converted into any kind of a number,
+          ** then the seek is not possible, so jump to P2 */
+          pc = pOp->p2 - 1;
+          break;
+        }
+        /* If we reach this point, then the P3 value must be a floating
+        ** point number. */
+        assert( (pIn3->flags & MEM_Real)!=0 );
+
+        if( u.az.iKey==SMALLEST_INT64 && (pIn3->r<(double)u.az.iKey || pIn3->r>0) ){
+          /* The P3 value is too large in magnitude to be expressed as an
+          ** integer. */
+          u.az.res = 1;
+          if( pIn3->r<0 ){
+            if( u.az.oc==OP_SeekGt || u.az.oc==OP_SeekGe ){
+              rc = sqlite3BtreeFirst(u.az.pC->pCursor, &u.az.res);
+              if( rc!=SQLITE_OK ) goto abort_due_to_error;
+            }
+          }else{
+            if( u.az.oc==OP_SeekLt || u.az.oc==OP_SeekLe ){
+              rc = sqlite3BtreeLast(u.az.pC->pCursor, &u.az.res);
+              if( rc!=SQLITE_OK ) goto abort_due_to_error;
+            }
+          }
+          if( u.az.res ){
+            pc = pOp->p2 - 1;
+          }
+          break;
+        }else if( u.az.oc==OP_SeekLt || u.az.oc==OP_SeekGe ){
+          /* Use the ceiling() function to convert real->int */
+          if( pIn3->r > (double)u.az.iKey ) u.az.iKey++;
         }else{
-          codeInteger(v, (char*)p->z, p->n, 1, target);
+          /* Use the floor() function to convert real->int */
+          assert( u.az.oc==OP_SeekLe || u.az.oc==OP_SeekGt );
+          if( pIn3->r < (double)u.az.iKey ) u.az.iKey--;
         }
-      }else{
-        regFree1 = r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
-        r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree2);
-        sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
-        testcase( regFree2==0 );
       }
-      inReg = target;
-      break;
-    }
-    case TK_BITNOT:
-    case TK_NOT: {
-      assert( TK_BITNOT==OP_BitNot );
-      assert( TK_NOT==OP_Not );
-      testcase( op==TK_BITNOT );
-      testcase( op==TK_NOT );
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-      testcase( inReg==target );
-      testcase( usedAsColumnCache(pParse, inReg, inReg) );
-      inReg = sqlite3ExprWritableRegister(pParse, inReg, target);
-      sqlite3VdbeAddOp1(v, op, inReg);
-      break;
-    }
-    case TK_ISNULL:
-    case TK_NOTNULL: {
-      int addr;
-      assert( TK_ISNULL==OP_IsNull );
-      assert( TK_NOTNULL==OP_NotNull );
-      testcase( op==TK_ISNULL );
-      testcase( op==TK_NOTNULL );
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      testcase( regFree1==0 );
-      addr = sqlite3VdbeAddOp1(v, op, r1);
-      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
-      sqlite3VdbeJumpHere(v, addr);
-      break;
-    }
-    case TK_AGG_FUNCTION: {
-      AggInfo *pInfo = pExpr->pAggInfo;
-      if( pInfo==0 ){
-        sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",
-            &pExpr->span);
-      }else{
-        inReg = pInfo->aFunc[pExpr->iAgg].iMem;
+      rc = sqlite3BtreeMovetoUnpacked(u.az.pC->pCursor, 0, (u64)u.az.iKey, 0, &u.az.res);
+      if( rc!=SQLITE_OK ){
+        goto abort_due_to_error;
       }
-      break;
-    }
-    case TK_CONST_FUNC:
-    case TK_FUNCTION: {
-      ExprList *pList = pExpr->pList;
-      int nExpr = pList ? pList->nExpr : 0;
-      FuncDef *pDef;
-      int nId;
-      const char *zId;
-      int constMask = 0;
-      int i;
-      sqlite3 *db = pParse->db;
-      u8 enc = ENC(db);
-      CollSeq *pColl = 0;
-
-      testcase( op==TK_CONST_FUNC );
-      testcase( op==TK_FUNCTION );
-      zId = (char*)pExpr->token.z;
-      nId = pExpr->token.n;
-      pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
-      assert( pDef!=0 );
-      if( pList ){
-        nExpr = pList->nExpr;
-        r1 = sqlite3GetTempRange(pParse, nExpr);
-        sqlite3ExprCodeExprList(pParse, pList, r1, 1);
+      if( u.az.res==0 ){
+        u.az.pC->rowidIsValid = 1;
+        u.az.pC->lastRowid = u.az.iKey;
+      }
+    }else{
+      u.az.nField = pOp->p4.i;
+      assert( pOp->p4type==P4_INT32 );
+      assert( u.az.nField>0 );
+      u.az.r.pKeyInfo = u.az.pC->pKeyInfo;
+      u.az.r.nField = (u16)u.az.nField;
+      if( u.az.oc==OP_SeekGt || u.az.oc==OP_SeekLe ){
+        u.az.r.flags = UNPACKED_INCRKEY;
       }else{
-        nExpr = r1 = 0;
+        u.az.r.flags = 0;
       }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      /* Possibly overload the function if the first argument is
-      ** a virtual table column.
-      **
-      ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
-      ** second argument, not the first, as the argument to test to
-      ** see if it is a column in a virtual table.  This is done because
-      ** the left operand of infix functions (the operand we want to
-      ** control overloading) ends up as the second argument to the
-      ** function.  The expression "A glob B" is equivalent to 
-      ** "glob(B,A).  We want to use the A in "A glob B" to test
-      ** for function overloading.  But we use the B term in "glob(B,A)".
-      */
-      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
-        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
-      }else if( nExpr>0 ){
-        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
+      u.az.r.aMem = &p->aMem[pOp->p3];
+      rc = sqlite3BtreeMovetoUnpacked(u.az.pC->pCursor, &u.az.r, 0, 0, &u.az.res);
+      if( rc!=SQLITE_OK ){
+        goto abort_due_to_error;
       }
+      u.az.pC->rowidIsValid = 0;
+    }
+    u.az.pC->deferredMoveto = 0;
+    u.az.pC->cacheStatus = CACHE_STALE;
+#ifdef SQLITE_TEST
+    sqlite3_search_count++;
 #endif
-      for(i=0; i<nExpr && i<32; i++){
-        if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
-          constMask |= (1<<i);
-        }
-        if( pDef->needCollSeq && !pColl ){
-          pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
-        }
-      }
-      if( pDef->needCollSeq ){
-        if( !pColl ) pColl = pParse->db->pDfltColl; 
-        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
+    if( u.az.oc==OP_SeekGe || u.az.oc==OP_SeekGt ){
+      if( u.az.res<0 || (u.az.res==0 && u.az.oc==OP_SeekGt) ){
+        rc = sqlite3BtreeNext(u.az.pC->pCursor, &u.az.res);
+        if( rc!=SQLITE_OK ) goto abort_due_to_error;
+        u.az.pC->rowidIsValid = 0;
+      }else{
+        u.az.res = 0;
       }
-      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
-                        (char*)pDef, P4_FUNCDEF);
-      sqlite3VdbeChangeP5(v, nExpr);
-      if( nExpr ){
-        sqlite3ReleaseTempRange(pParse, r1, nExpr);
+    }else{
+      assert( u.az.oc==OP_SeekLt || u.az.oc==OP_SeekLe );
+      if( u.az.res>0 || (u.az.res==0 && u.az.oc==OP_SeekLt) ){
+        rc = sqlite3BtreePrevious(u.az.pC->pCursor, &u.az.res);
+        if( rc!=SQLITE_OK ) goto abort_due_to_error;
+        u.az.pC->rowidIsValid = 0;
+      }else{
+        /* u.az.res might be negative because the table is empty.  Check to
+        ** see if this is the case.
+        */
+        u.az.res = sqlite3BtreeEof(u.az.pC->pCursor);
       }
-      sqlite3ExprCacheAffinityChange(pParse, r1, nExpr);
-      break;
     }
-#ifndef SQLITE_OMIT_SUBQUERY
-    case TK_EXISTS:
-    case TK_SELECT: {
-      testcase( op==TK_EXISTS );
-      testcase( op==TK_SELECT );
-      if( pExpr->iColumn==0 ){
-        sqlite3CodeSubselect(pParse, pExpr);
-      }
-      inReg = pExpr->iColumn;
-      break;
+    assert( pOp->p2>0 );
+    if( u.az.res ){
+      pc = pOp->p2 - 1;
     }
-    case TK_IN: {
-      int j1, j2, j3, j4, j5;
-      char affinity;
-      int eType;
-
-      eType = sqlite3FindInIndex(pParse, pExpr, 0);
-
-      /* Figure out the affinity to use to create a key from the results
-      ** of the expression. affinityStr stores a static string suitable for
-      ** P4 of OP_MakeRecord.
-      */
-      affinity = comparisonAffinity(pExpr);
+  }else{
+    /* This happens when attempting to open the sqlite3_master table
+    ** for read access returns SQLITE_EMPTY. In this case always
+    ** take the jump (since there are no records in the table).
+    */
+    pc = pOp->p2 - 1;
+  }
+  break;
+}
 
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+/* Opcode: Seek P1 P2 * * *
+**
+** P1 is an open table cursor and P2 is a rowid integer.  Arrange
+** for P1 to move so that it points to the rowid given by P2.
+**
+** This is actually a deferred seek.  Nothing actually happens until
+** the cursor is used to read a record.  That way, if no reads
+** occur, no unnecessary I/O happens.
+*/
+case OP_Seek: {    /* in2 */
+#if 0  /* local variables moved into u.ba */
+  VdbeCursor *pC;
+#endif /* local variables moved into u.ba */
 
-      /* Code the <expr> from "<expr> IN (...)". The temporary table
-      ** pExpr->iTable contains the values that make up the (...) set.
-      */
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      testcase( regFree1==0 );
-      j1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1);
-      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
-      j2  = sqlite3VdbeAddOp0(v, OP_Goto);
-      sqlite3VdbeJumpHere(v, j1);
-      if( eType==IN_INDEX_ROWID ){
-        j3 = sqlite3VdbeAddOp1(v, OP_MustBeInt, r1);
-        j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, r1);
-        j5 = sqlite3VdbeAddOp0(v, OP_Goto);
-        sqlite3VdbeJumpHere(v, j3);
-        sqlite3VdbeJumpHere(v, j4);
-      }else{
-        r2 = regFree2 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1);
-        sqlite3ExprCacheAffinityChange(pParse, r1, 1);
-        j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
-      }
-      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
-      sqlite3VdbeJumpHere(v, j2);
-      sqlite3VdbeJumpHere(v, j5);
-      break;
-    }
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.ba.pC = p->apCsr[pOp->p1];
+  assert( u.ba.pC!=0 );
+  if( ALWAYS(u.ba.pC->pCursor!=0) ){
+    assert( u.ba.pC->isTable );
+    u.ba.pC->nullRow = 0;
+    u.ba.pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
+    u.ba.pC->rowidIsValid = 0;
+    u.ba.pC->deferredMoveto = 1;
+  }
+  break;
+}
+  
+
+/* Opcode: Found P1 P2 P3 * *
+**
+** Register P3 holds a blob constructed by MakeRecord.  P1 is an index.
+** If an entry that matches the value in register p3 exists in P1 then
+** jump to P2.  If the P3 value does not match any entry in P1
+** then fall thru.  The P1 cursor is left pointing at the matching entry
+** if it exists.
+**
+** This instruction is used to implement the IN operator where the
+** left-hand side is a SELECT statement.  P1 may be a true index, or it
+** may be a temporary index that holds the results of the SELECT
+** statement.   This instruction is also used to implement the
+** DISTINCT keyword in SELECT statements.
+**
+** This instruction checks if index P1 contains a record for which 
+** the first N serialized values exactly match the N serialized values
+** in the record in register P3, where N is the total number of values in
+** the P3 record (the P3 record is a prefix of the P1 record). 
+**
+** See also: NotFound, IsUnique, NotExists
+*/
+/* Opcode: NotFound P1 P2 P3 * *
+**
+** Register P3 holds a blob constructed by MakeRecord.  P1 is
+** an index.  If no entry exists in P1 that matches the blob then jump
+** to P2.  If an entry does existing, fall through.  The cursor is left
+** pointing to the entry that matches.
+**
+** See also: Found, NotExists, IsUnique
+*/
+case OP_NotFound:       /* jump, in3 */
+case OP_Found: {        /* jump, in3 */
+#if 0  /* local variables moved into u.bb */
+  int alreadyExists;
+  VdbeCursor *pC;
+  int res;
+  UnpackedRecord *pIdxKey;
+  char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*3 + 7];
+#endif /* local variables moved into u.bb */
+
+#ifdef SQLITE_TEST
+  sqlite3_found_count++;
 #endif
-    /*
-    **    x BETWEEN y AND z
-    **
-    ** This is equivalent to
-    **
-    **    x>=y AND x<=z
-    **
-    ** X is stored in pExpr->pLeft.
-    ** Y is stored in pExpr->pList->a[0].pExpr.
-    ** Z is stored in pExpr->pList->a[1].pExpr.
-    */
-    case TK_BETWEEN: {
-      Expr *pLeft = pExpr->pLeft;
-      struct ExprList_item *pLItem = pExpr->pList->a;
-      Expr *pRight = pLItem->pExpr;
 
-      codeCompareOperands(pParse, pLeft, &r1, &regFree1,
-                                  pRight, &r2, &regFree2);
-      testcase( regFree1==0 );
-      testcase( regFree2==0 );
-      r3 = sqlite3GetTempReg(pParse);
-      r4 = sqlite3GetTempReg(pParse);
-      codeCompare(pParse, pLeft, pRight, OP_Ge,
-                  r1, r2, r3, SQLITE_STOREP2);
-      pLItem++;
-      pRight = pLItem->pExpr;
-      sqlite3ReleaseTempReg(pParse, regFree2);
-      r2 = sqlite3ExprCodeTemp(pParse, pRight, &regFree2);
-      testcase( regFree2==0 );
-      codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
-      sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
-      sqlite3ReleaseTempReg(pParse, r3);
-      sqlite3ReleaseTempReg(pParse, r4);
+  u.bb.alreadyExists = 0;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bb.pC = p->apCsr[pOp->p1];
+  assert( u.bb.pC!=0 );
+  if( ALWAYS(u.bb.pC->pCursor!=0) ){
+
+    assert( u.bb.pC->isTable==0 );
+    assert( pIn3->flags & MEM_Blob );
+    ExpandBlob(pIn3);
+    u.bb.pIdxKey = sqlite3VdbeRecordUnpack(u.bb.pC->pKeyInfo, pIn3->n, pIn3->z,
+                                      u.bb.aTempRec, sizeof(u.bb.aTempRec));
+    if( u.bb.pIdxKey==0 ){
+      goto no_mem;
+    }
+    if( pOp->opcode==OP_Found ){
+      u.bb.pIdxKey->flags |= UNPACKED_PREFIX_MATCH;
+    }
+    rc = sqlite3BtreeMovetoUnpacked(u.bb.pC->pCursor, u.bb.pIdxKey, 0, 0, &u.bb.res);
+    sqlite3VdbeDeleteUnpackedRecord(u.bb.pIdxKey);
+    if( rc!=SQLITE_OK ){
       break;
     }
-    case TK_UPLUS: {
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+    u.bb.alreadyExists = (u.bb.res==0);
+    u.bb.pC->deferredMoveto = 0;
+    u.bb.pC->cacheStatus = CACHE_STALE;
+  }
+  if( pOp->opcode==OP_Found ){
+    if( u.bb.alreadyExists ) pc = pOp->p2 - 1;
+  }else{
+    if( !u.bb.alreadyExists ) pc = pOp->p2 - 1;
+  }
+  break;
+}
+
+/* Opcode: IsUnique P1 P2 P3 P4 *
+**
+** Cursor P1 is open on an index.  So it has no data and its key consists 
+** of a record generated by OP_MakeRecord where the last field is the 
+** rowid of the entry that the index refers to.
+**
+** The P3 register contains an integer record number. Call this record 
+** number R. Register P4 is the first in a set of N contiguous registers
+** that make up an unpacked index key that can be used with cursor P1.
+** The value of N can be inferred from the cursor. N includes the rowid
+** value appended to the end of the index record. This rowid value may
+** or may not be the same as R.
+**
+** If any of the N registers beginning with register P4 contains a NULL
+** value, jump immediately to P2.
+**
+** Otherwise, this instruction checks if cursor P1 contains an entry
+** where the first (N-1) fields match but the rowid value at the end
+** of the index entry is not R. If there is no such entry, control jumps
+** to instruction P2. Otherwise, the rowid of the conflicting index
+** entry is copied to register P3 and control falls through to the next
+** instruction.
+**
+** See also: NotFound, NotExists, Found
+*/
+case OP_IsUnique: {        /* jump, in3 */
+#if 0  /* local variables moved into u.bc */
+  u16 ii;
+  VdbeCursor *pCx;
+  BtCursor *pCrsr;
+  u16 nField;
+  Mem *aMem;
+  UnpackedRecord r;                  /* B-Tree index search key */
+  i64 R;                             /* Rowid stored in register P3 */
+#endif /* local variables moved into u.bc */
+
+  u.bc.aMem = &p->aMem[pOp->p4.i];
+  /* Assert that the values of parameters P1 and P4 are in range. */
+  assert( pOp->p4type==P4_INT32 );
+  assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+
+  /* Find the index cursor. */
+  u.bc.pCx = p->apCsr[pOp->p1];
+  assert( u.bc.pCx->deferredMoveto==0 );
+  u.bc.pCx->seekResult = 0;
+  u.bc.pCx->cacheStatus = CACHE_STALE;
+  u.bc.pCrsr = u.bc.pCx->pCursor;
+
+  /* If any of the values are NULL, take the jump. */
+  u.bc.nField = u.bc.pCx->pKeyInfo->nField;
+  for(u.bc.ii=0; u.bc.ii<u.bc.nField; u.bc.ii++){
+    if( u.bc.aMem[u.bc.ii].flags & MEM_Null ){
+      pc = pOp->p2 - 1;
+      u.bc.pCrsr = 0;
       break;
     }
+  }
+  assert( (u.bc.aMem[u.bc.nField].flags & MEM_Null)==0 );
 
-    /*
-    ** Form A:
-    **   CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
-    **
-    ** Form B:
-    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
-    **
-    ** Form A is can be transformed into the equivalent form B as follows:
-    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
-    **        WHEN x=eN THEN rN ELSE y END
+  if( u.bc.pCrsr!=0 ){
+    /* Populate the index search key. */
+    u.bc.r.pKeyInfo = u.bc.pCx->pKeyInfo;
+    u.bc.r.nField = u.bc.nField + 1;
+    u.bc.r.flags = UNPACKED_PREFIX_SEARCH;
+    u.bc.r.aMem = u.bc.aMem;
+
+    /* Extract the value of u.bc.R from register P3. */
+    sqlite3VdbeMemIntegerify(pIn3);
+    u.bc.R = pIn3->u.i;
+
+    /* Search the B-Tree index. If no conflicting record is found, jump
+    ** to P2. Otherwise, copy the rowid of the conflicting record to
+    ** register P3 and fall through to the next instruction.  */
+    rc = sqlite3BtreeMovetoUnpacked(u.bc.pCrsr, &u.bc.r, 0, 0, &u.bc.pCx->seekResult);
+    if( (u.bc.r.flags & UNPACKED_PREFIX_SEARCH) || u.bc.r.rowid==u.bc.R ){
+      pc = pOp->p2 - 1;
+    }else{
+      pIn3->u.i = u.bc.r.rowid;
+    }
+  }
+  break;
+}
+
+/* Opcode: NotExists P1 P2 P3 * *
+**
+** Use the content of register P3 as a integer key.  If a record 
+** with that key does not exist in table of P1, then jump to P2. 
+** If the record does exist, then fall thru.  The cursor is left 
+** pointing to the record if it exists.
+**
+** The difference between this operation and NotFound is that this
+** operation assumes the key is an integer and that P1 is a table whereas
+** NotFound assumes key is a blob constructed from MakeRecord and
+** P1 is an index.
+**
+** See also: Found, NotFound, IsUnique
+*/
+case OP_NotExists: {        /* jump, in3 */
+#if 0  /* local variables moved into u.bd */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int res;
+  u64 iKey;
+#endif /* local variables moved into u.bd */
+
+  assert( pIn3->flags & MEM_Int );
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bd.pC = p->apCsr[pOp->p1];
+  assert( u.bd.pC!=0 );
+  assert( u.bd.pC->isTable );
+  assert( u.bd.pC->pseudoTableReg==0 );
+  u.bd.pCrsr = u.bd.pC->pCursor;
+  if( u.bd.pCrsr!=0 ){
+    u.bd.res = 0;
+    u.bd.iKey = pIn3->u.i;
+    rc = sqlite3BtreeMovetoUnpacked(u.bd.pCrsr, 0, u.bd.iKey, 0, &u.bd.res);
+    u.bd.pC->lastRowid = pIn3->u.i;
+    u.bd.pC->rowidIsValid = u.bd.res==0 ?1:0;
+    u.bd.pC->nullRow = 0;
+    u.bd.pC->cacheStatus = CACHE_STALE;
+    u.bd.pC->deferredMoveto = 0;
+    if( u.bd.res!=0 ){
+      pc = pOp->p2 - 1;
+      assert( u.bd.pC->rowidIsValid==0 );
+    }
+    u.bd.pC->seekResult = u.bd.res;
+  }else{
+    /* This happens when an attempt to open a read cursor on the
+    ** sqlite_master table returns SQLITE_EMPTY.
+    */
+    pc = pOp->p2 - 1;
+    assert( u.bd.pC->rowidIsValid==0 );
+    u.bd.pC->seekResult = 0;
+  }
+  break;
+}
+
+/* Opcode: Sequence P1 P2 * * *
+**
+** Find the next available sequence number for cursor P1.
+** Write the sequence number into register P2.
+** The sequence number on the cursor is incremented after this
+** instruction.  
+*/
+case OP_Sequence: {           /* out2-prerelease */
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  assert( p->apCsr[pOp->p1]!=0 );
+  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
+  MemSetTypeFlag(pOut, MEM_Int);
+  break;
+}
+
+
+/* Opcode: NewRowid P1 P2 P3 * *
+**
+** Get a new integer record number (a.k.a "rowid") used as the key to a table.
+** The record number is not previously used as a key in the database
+** table that cursor P1 points to.  The new record number is written
+** written to register P2.
+**
+** If P3>0 then P3 is a register in the root frame of this VDBE that holds 
+** the largest previously generated record number. No new record numbers are
+** allowed to be less than this value. When this value reaches its maximum, 
+** a SQLITE_FULL error is generated. The P3 register is updated with the '
+** generated record number. This P3 mechanism is used to help implement the
+** AUTOINCREMENT feature.
+*/
+case OP_NewRowid: {           /* out2-prerelease */
+#if 0  /* local variables moved into u.be */
+  i64 v;                 /* The new rowid */
+  VdbeCursor *pC;        /* Cursor of table to get the new rowid */
+  int res;               /* Result of an sqlite3BtreeLast() */
+  int cnt;               /* Counter to limit the number of searches */
+  Mem *pMem;             /* Register holding largest rowid for AUTOINCREMENT */
+  VdbeFrame *pFrame;     /* Root frame of VDBE */
+#endif /* local variables moved into u.be */
+
+  u.be.v = 0;
+  u.be.res = 0;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.be.pC = p->apCsr[pOp->p1];
+  assert( u.be.pC!=0 );
+  if( NEVER(u.be.pC->pCursor==0) ){
+    /* The zero initialization above is all that is needed */
+  }else{
+    /* The next rowid or record number (different terms for the same
+    ** thing) is obtained in a two-step algorithm.
     **
-    ** X (if it exists) is in pExpr->pLeft.
-    ** Y is in pExpr->pRight.  The Y is also optional.  If there is no
-    ** ELSE clause and no other term matches, then the result of the
-    ** exprssion is NULL.
-    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
+    ** First we attempt to find the largest existing rowid and add one
+    ** to that.  But if the largest existing rowid is already the maximum
+    ** positive integer, we have to fall through to the second
+    ** probabilistic algorithm
     **
-    ** The result of the expression is the Ri for the first matching Ei,
-    ** or if there is no matching Ei, the ELSE term Y, or if there is
-    ** no ELSE term, NULL.
+    ** The second algorithm is to select a rowid at random and see if
+    ** it already exists in the table.  If it does not exist, we have
+    ** succeeded.  If the random rowid does exist, we select a new one
+    ** and try again, up to 100 times.
     */
-    case TK_CASE: {
-      int endLabel;                     /* GOTO label for end of CASE stmt */
-      int nextCase;                     /* GOTO label for next WHEN clause */
-      int nExpr;                        /* 2x number of WHEN terms */
-      int i;                            /* Loop counter */
-      ExprList *pEList;                 /* List of WHEN terms */
-      struct ExprList_item *aListelem;  /* Array of WHEN terms */
-      Expr opCompare;                   /* The X==Ei expression */
-      Expr cacheX;                      /* Cached expression X */
-      Expr *pX;                         /* The X expression */
-      Expr *pTest;                      /* X==Ei (form A) or just Ei (form B) */
+    assert( u.be.pC->isTable );
+    u.be.cnt = 0;
 
-      assert(pExpr->pList);
-      assert((pExpr->pList->nExpr % 2) == 0);
-      assert(pExpr->pList->nExpr > 0);
-      pEList = pExpr->pList;
-      aListelem = pEList->a;
-      nExpr = pEList->nExpr;
-      endLabel = sqlite3VdbeMakeLabel(v);
-      if( (pX = pExpr->pLeft)!=0 ){
-        cacheX = *pX;
-        testcase( pX->op==TK_COLUMN || pX->op==TK_REGISTER );
-        cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, &regFree1);
-        testcase( regFree1==0 );
-        cacheX.op = TK_REGISTER;
-        cacheX.iColumn = 0;
-        opCompare.op = TK_EQ;
-        opCompare.pLeft = &cacheX;
-        pTest = &opCompare;
-      }
-      pParse->disableColCache++;
-      for(i=0; i<nExpr; i=i+2){
-        if( pX ){
-          opCompare.pRight = aListelem[i].pExpr;
+#ifdef SQLITE_32BIT_ROWID
+#   define MAX_ROWID 0x7fffffff
+#else
+    /* Some compilers complain about constants of the form 0x7fffffffffffffff.
+    ** Others complain about 0x7ffffffffffffffffLL.  The following macro seems
+    ** to provide the constant while making all compilers happy.
+    */
+#   define MAX_ROWID  (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
+#endif
+
+    if( !u.be.pC->useRandomRowid ){
+      u.be.v = sqlite3BtreeGetCachedRowid(u.be.pC->pCursor);
+      if( u.be.v==0 ){
+        rc = sqlite3BtreeLast(u.be.pC->pCursor, &u.be.res);
+        if( rc!=SQLITE_OK ){
+          goto abort_due_to_error;
+        }
+        if( u.be.res ){
+          u.be.v = 1;
         }else{
-          pTest = aListelem[i].pExpr;
+          assert( sqlite3BtreeCursorIsValid(u.be.pC->pCursor) );
+          rc = sqlite3BtreeKeySize(u.be.pC->pCursor, &u.be.v);
+          assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
+          if( u.be.v==MAX_ROWID ){
+            u.be.pC->useRandomRowid = 1;
+          }else{
+            u.be.v++;
+          }
         }
-        nextCase = sqlite3VdbeMakeLabel(v);
-        testcase( pTest->op==TK_COLUMN || pTest->op==TK_REGISTER );
-        sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
-        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
-        testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
-        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
-        sqlite3VdbeResolveLabel(v, nextCase);
       }
-      if( pExpr->pRight ){
-        sqlite3ExprCode(pParse, pExpr->pRight, target);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+      if( pOp->p3 ){
+        /* Assert that P3 is a valid memory cell. */
+        assert( pOp->p3>0 );
+        if( p->pFrame ){
+          for(u.be.pFrame=p->pFrame; u.be.pFrame->pParent; u.be.pFrame=u.be.pFrame->pParent);
+          /* Assert that P3 is a valid memory cell. */
+          assert( pOp->p3<=u.be.pFrame->nMem );
+          u.be.pMem = &u.be.pFrame->aMem[pOp->p3];
+        }else{
+          /* Assert that P3 is a valid memory cell. */
+          assert( pOp->p3<=p->nMem );
+          u.be.pMem = &p->aMem[pOp->p3];
+        }
+
+        REGISTER_TRACE(pOp->p3, u.be.pMem);
+        sqlite3VdbeMemIntegerify(u.be.pMem);
+        assert( (u.be.pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
+        if( u.be.pMem->u.i==MAX_ROWID || u.be.pC->useRandomRowid ){
+          rc = SQLITE_FULL;
+          goto abort_due_to_error;
+        }
+        if( u.be.v<u.be.pMem->u.i+1 ){
+          u.be.v = u.be.pMem->u.i + 1;
+        }
+        u.be.pMem->u.i = u.be.v;
       }
-      sqlite3VdbeResolveLabel(v, endLabel);
-      assert( pParse->disableColCache>0 );
-      pParse->disableColCache--;
-      break;
+#endif
+
+      sqlite3BtreeSetCachedRowid(u.be.pC->pCursor, u.be.v<MAX_ROWID ? u.be.v+1 : 0);
     }
-#ifndef SQLITE_OMIT_TRIGGER
-    case TK_RAISE: {
-      if( !pParse->trigStack ){
-        sqlite3ErrorMsg(pParse,
-                       "RAISE() may only be used within a trigger-program");
-        return 0;
-      }
-      if( pExpr->iColumn!=OE_Ignore ){
-         assert( pExpr->iColumn==OE_Rollback ||
-                 pExpr->iColumn == OE_Abort ||
-                 pExpr->iColumn == OE_Fail );
-         sqlite3DequoteExpr(pParse->db, pExpr);
-         sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, 0,
-                        (char*)pExpr->token.z, pExpr->token.n);
-      } else {
-         assert( pExpr->iColumn == OE_Ignore );
-         sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
-         sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
-         VdbeComment((v, "raise(IGNORE)"));
+    if( u.be.pC->useRandomRowid ){
+      assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
+                             ** an AUTOINCREMENT table. */
+      u.be.v = db->lastRowid;
+      u.be.cnt = 0;
+      do{
+        if( u.be.cnt==0 && (u.be.v&0xffffff)==u.be.v ){
+          u.be.v++;
+        }else{
+          sqlite3_randomness(sizeof(u.be.v), &u.be.v);
+          if( u.be.cnt<5 ) u.be.v &= 0xffffff;
+        }
+        rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, 0, (u64)u.be.v, 0, &u.be.res);
+        u.be.cnt++;
+      }while( u.be.cnt<100 && rc==SQLITE_OK && u.be.res==0 );
+      if( rc==SQLITE_OK && u.be.res==0 ){
+        rc = SQLITE_FULL;
+        goto abort_due_to_error;
       }
-      break;
     }
-#endif
+    u.be.pC->rowidIsValid = 0;
+    u.be.pC->deferredMoveto = 0;
+    u.be.pC->cacheStatus = CACHE_STALE;
   }
-  sqlite3ReleaseTempReg(pParse, regFree1);
-  sqlite3ReleaseTempReg(pParse, regFree2);
-  return inReg;
+  MemSetTypeFlag(pOut, MEM_Int);
+  pOut->u.i = u.be.v;
+  break;
 }
 
-/*
-** Generate code to evaluate an expression and store the results
-** into a register.  Return the register number where the results
-** are stored.
+/* Opcode: Insert P1 P2 P3 P4 P5
 **
-** If the register is a temporary register that can be deallocated,
-** then write its number into *pReg.  If the result register is not
-** a temporary, then set *pReg to zero.
+** Write an entry into the table of cursor P1.  A new entry is
+** created if it doesn't already exist or the data for an existing
+** entry is overwritten.  The data is the value MEM_Blob stored in register
+** number P2. The key is stored in register P3. The key must
+** be a MEM_Int.
+**
+** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
+** incremented (otherwise not).  If the OPFLAG_LASTROWID flag of P5 is set,
+** then rowid is stored for subsequent return by the
+** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
+**
+** If the OPFLAG_USESEEKRESULT flag of P5 is set and if the result of
+** the last seek operation (OP_NotExists) was a success, then this
+** operation will not attempt to find the appropriate row before doing
+** the insert but will instead overwrite the row that the cursor is
+** currently pointing to.  Presumably, the prior OP_NotExists opcode
+** has already positioned the cursor correctly.  This is an optimization
+** that boosts performance by avoiding redundant seeks.
+**
+** If the OPFLAG_ISUPDATE flag is set, then this opcode is part of an
+** UPDATE operation.  Otherwise (if the flag is clear) then this opcode
+** is part of an INSERT operation.  The difference is only important to
+** the update hook.
+**
+** Parameter P4 may point to a string containing the table-name, or
+** may be NULL. If it is not NULL, then the update-hook 
+** (sqlite3.xUpdateCallback) is invoked following a successful insert.
+**
+** (WARNING/TODO: If P1 is a pseudo-cursor and P2 is dynamically
+** allocated, then ownership of P2 is transferred to the pseudo-cursor
+** and register P2 becomes ephemeral.  If the cursor is changed, the
+** value of register P2 will then change.  Make sure this does not
+** cause any problems.)
+**
+** This instruction only works on tables.  The equivalent instruction
+** for indices is OP_IdxInsert.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
-  int r1 = sqlite3GetTempReg(pParse);
-  int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
-  if( r2==r1 ){
-    *pReg = r1;
+case OP_Insert: {
+#if 0  /* local variables moved into u.bf */
+  Mem *pData;       /* MEM cell holding data for the record to be inserted */
+  Mem *pKey;        /* MEM cell holding key  for the record */
+  i64 iKey;         /* The integer ROWID or key for the record to be inserted */
+  VdbeCursor *pC;   /* Cursor to table into which insert is written */
+  int nZero;        /* Number of zero-bytes to append */
+  int seekResult;   /* Result of prior seek or 0 if no USESEEKRESULT flag */
+  const char *zDb;  /* database name - used by the update hook */
+  const char *zTbl; /* Table name - used by the opdate hook */
+  int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */
+#endif /* local variables moved into u.bf */
+
+  u.bf.pData = &p->aMem[pOp->p2];
+  u.bf.pKey = &p->aMem[pOp->p3];
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bf.pC = p->apCsr[pOp->p1];
+  assert( u.bf.pC!=0 );
+  assert( u.bf.pC->pCursor!=0 );
+  assert( u.bf.pC->pseudoTableReg==0 );
+  assert( u.bf.pKey->flags & MEM_Int );
+  assert( u.bf.pC->isTable );
+  REGISTER_TRACE(pOp->p2, u.bf.pData);
+  REGISTER_TRACE(pOp->p3, u.bf.pKey);
+
+  u.bf.iKey = u.bf.pKey->u.i;
+  if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
+  if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = u.bf.pKey->u.i;
+  if( u.bf.pData->flags & MEM_Null ){
+    u.bf.pData->z = 0;
+    u.bf.pData->n = 0;
   }else{
-    sqlite3ReleaseTempReg(pParse, r1);
-    *pReg = 0;
+    assert( u.bf.pData->flags & (MEM_Blob|MEM_Str) );
   }
-  return r2;
-}
-
-/*
-** Generate code that will evaluate expression pExpr and store the
-** results in register target.  The results are guaranteed to appear
-** in register target.
-*/
-SQLITE_PRIVATE int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
-  int inReg;
+  u.bf.seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bf.pC->seekResult : 0);
+  if( u.bf.pData->flags & MEM_Zero ){
+    u.bf.nZero = u.bf.pData->u.nZero;
+  }else{
+    u.bf.nZero = 0;
+  }
+  sqlite3BtreeSetCachedRowid(u.bf.pC->pCursor, 0);
+  rc = sqlite3BtreeInsert(u.bf.pC->pCursor, 0, u.bf.iKey,
+                          u.bf.pData->z, u.bf.pData->n, u.bf.nZero,
+                          pOp->p5 & OPFLAG_APPEND, u.bf.seekResult
+  );
+  u.bf.pC->rowidIsValid = 0;
+  u.bf.pC->deferredMoveto = 0;
+  u.bf.pC->cacheStatus = CACHE_STALE;
 
-  assert( target>0 && target<=pParse->nMem );
-  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-  assert( pParse->pVdbe || pParse->db->mallocFailed );
-  if( inReg!=target && pParse->pVdbe ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+  /* Invoke the update-hook if required. */
+  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
+    u.bf.zDb = db->aDb[u.bf.pC->iDb].zName;
+    u.bf.zTbl = pOp->p4.z;
+    u.bf.op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
+    assert( u.bf.pC->isTable );
+    db->xUpdateCallback(db->pUpdateArg, u.bf.op, u.bf.zDb, u.bf.zTbl, u.bf.iKey);
+    assert( u.bf.pC->iDb>=0 );
   }
-  return target;
+  break;
 }
 
-/*
-** Generate code that evalutes the given expression and puts the result
-** in register target.
+/* Opcode: Delete P1 P2 * P4 *
 **
-** Also make a copy of the expression results into another "cache" register
-** and modify the expression so that the next time it is evaluated,
-** the result is a copy of the cache register.
+** Delete the record at which the P1 cursor is currently pointing.
 **
-** This routine is used for expressions that are used multiple 
-** times.  They are evaluated once and the results of the expression
-** are reused.
+** The cursor will be left pointing at either the next or the previous
+** record in the table. If it is left pointing at the next record, then
+** the next Next instruction will be a no-op.  Hence it is OK to delete
+** a record from within an Next loop.
+**
+** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
+** incremented (otherwise not).
+**
+** P1 must not be pseudo-table.  It has to be a real table with
+** multiple rows.
+**
+** If P4 is not NULL, then it is the name of the table that P1 is
+** pointing to.  The update hook will be invoked, if it exists.
+** If P4 is not NULL then the P1 cursor must have been positioned
+** using OP_NotFound prior to invoking this opcode.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
-  Vdbe *v = pParse->pVdbe;
-  int inReg;
-  inReg = sqlite3ExprCode(pParse, pExpr, target);
-  assert( target>0 );
-  if( pExpr->op!=TK_REGISTER ){  
-    int iMem;
-    iMem = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
-    pExpr->iTable = iMem;
-    pExpr->iColumn = pExpr->op;
-    pExpr->op = TK_REGISTER;
+case OP_Delete: {
+#if 0  /* local variables moved into u.bg */
+  i64 iKey;
+  VdbeCursor *pC;
+#endif /* local variables moved into u.bg */
+
+  u.bg.iKey = 0;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bg.pC = p->apCsr[pOp->p1];
+  assert( u.bg.pC!=0 );
+  assert( u.bg.pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
+
+  /* If the update-hook will be invoked, set u.bg.iKey to the rowid of the
+  ** row being deleted.
+  */
+  if( db->xUpdateCallback && pOp->p4.z ){
+    assert( u.bg.pC->isTable );
+    assert( u.bg.pC->rowidIsValid );  /* lastRowid set by previous OP_NotFound */
+    u.bg.iKey = u.bg.pC->lastRowid;
+  }
+
+  /* The OP_Delete opcode always follows an OP_NotExists or OP_Last or
+  ** OP_Column on the same table without any intervening operations that
+  ** might move or invalidate the cursor.  Hence cursor u.bg.pC is always pointing
+  ** to the row to be deleted and the sqlite3VdbeCursorMoveto() operation
+  ** below is always a no-op and cannot fail.  We will run it anyhow, though,
+  ** to guard against future changes to the code generator.
+  **/
+  assert( u.bg.pC->deferredMoveto==0 );
+  rc = sqlite3VdbeCursorMoveto(u.bg.pC);
+  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
+
+  sqlite3BtreeSetCachedRowid(u.bg.pC->pCursor, 0);
+  rc = sqlite3BtreeDelete(u.bg.pC->pCursor);
+  u.bg.pC->cacheStatus = CACHE_STALE;
+
+  /* Invoke the update-hook if required. */
+  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
+    const char *zDb = db->aDb[u.bg.pC->iDb].zName;
+    const char *zTbl = pOp->p4.z;
+    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, u.bg.iKey);
+    assert( u.bg.pC->iDb>=0 );
   }
-  return inReg;
+  if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
+  break;
+}
+/* Opcode: ResetCount * * * * *
+**
+** The value of the change counter is copied to the database handle
+** change counter (returned by subsequent calls to sqlite3_changes()).
+** Then the VMs internal change counter resets to 0.
+** This is used by trigger programs.
+*/
+case OP_ResetCount: {
+  sqlite3VdbeSetChanges(db, p->nChange);
+  p->nChange = 0;
+  break;
 }
 
-/*
-** Return TRUE if pExpr is an constant expression that is appropriate
-** for factoring out of a loop.  Appropriate expressions are:
+/* Opcode: RowData P1 P2 * * *
 **
-**    *  Any expression that evaluates to two or more opcodes.
+** Write into register P2 the complete row data for cursor P1.
+** There is no interpretation of the data.  
+** It is just copied onto the P2 register exactly as 
+** it is found in the database file.
 **
-**    *  Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null, 
-**       or OP_Variable that does not need to be placed in a 
-**       specific register.
+** If the P1 cursor must be pointing to a valid row (not a NULL row)
+** of a real table, not a pseudo-table.
+*/
+/* Opcode: RowKey P1 P2 * * *
 **
-** There is no point in factoring out single-instruction constant
-** expressions that need to be placed in a particular register.  
-** We could factor them out, but then we would end up adding an
-** OP_SCopy instruction to move the value into the correct register
-** later.  We might as well just use the original instruction and
-** avoid the OP_SCopy.
+** Write into register P2 the complete row key for cursor P1.
+** There is no interpretation of the data.  
+** The key is copied onto the P3 register exactly as 
+** it is found in the database file.
+**
+** If the P1 cursor must be pointing to a valid row (not a NULL row)
+** of a real table, not a pseudo-table.
 */
-static int isAppropriateForFactoring(Expr *p){
-  if( !sqlite3ExprIsConstantNotJoin(p) ){
-    return 0;  /* Only constant expressions are appropriate for factoring */
-  }
-  if( (p->flags & EP_FixedDest)==0 ){
-    return 1;  /* Any constant without a fixed destination is appropriate */
-  }
-  while( p->op==TK_UPLUS ) p = p->pLeft;
-  switch( p->op ){
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-    case TK_BLOB:
-#endif
-    case TK_VARIABLE:
-    case TK_INTEGER:
-    case TK_FLOAT:
-    case TK_NULL:
-    case TK_STRING: {
-      testcase( p->op==TK_BLOB );
-      testcase( p->op==TK_VARIABLE );
-      testcase( p->op==TK_INTEGER );
-      testcase( p->op==TK_FLOAT );
-      testcase( p->op==TK_NULL );
-      testcase( p->op==TK_STRING );
-      /* Single-instruction constants with a fixed destination are
-      ** better done in-line.  If we factor them, they will just end
-      ** up generating an OP_SCopy to move the value to the destination
-      ** register. */
-      return 0;
-    }
-    case TK_UMINUS: {
-       if( p->pLeft->op==TK_FLOAT || p->pLeft->op==TK_INTEGER ){
-         return 0;
-       }
-       break;
+case OP_RowKey:
+case OP_RowData: {
+#if 0  /* local variables moved into u.bh */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  u32 n;
+  i64 n64;
+#endif /* local variables moved into u.bh */
+
+  pOut = &p->aMem[pOp->p2];
+
+  /* Note that RowKey and RowData are really exactly the same instruction */
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bh.pC = p->apCsr[pOp->p1];
+  assert( u.bh.pC->isTable || pOp->opcode==OP_RowKey );
+  assert( u.bh.pC->isIndex || pOp->opcode==OP_RowData );
+  assert( u.bh.pC!=0 );
+  assert( u.bh.pC->nullRow==0 );
+  assert( u.bh.pC->pseudoTableReg==0 );
+  assert( u.bh.pC->pCursor!=0 );
+  u.bh.pCrsr = u.bh.pC->pCursor;
+  assert( sqlite3BtreeCursorIsValid(u.bh.pCrsr) );
+
+  /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or
+  ** OP_Rewind/Op_Next with no intervening instructions that might invalidate
+  ** the cursor.  Hence the following sqlite3VdbeCursorMoveto() call is always
+  ** a no-op and can never fail.  But we leave it in place as a safety.
+  */
+  assert( u.bh.pC->deferredMoveto==0 );
+  rc = sqlite3VdbeCursorMoveto(u.bh.pC);
+  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
+
+  if( u.bh.pC->isIndex ){
+    assert( !u.bh.pC->isTable );
+    rc = sqlite3BtreeKeySize(u.bh.pCrsr, &u.bh.n64);
+    assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
+    if( u.bh.n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+      goto too_big;
     }
-    default: {
-      break;
+    u.bh.n = (u32)u.bh.n64;
+  }else{
+    rc = sqlite3BtreeDataSize(u.bh.pCrsr, &u.bh.n);
+    assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
+    if( u.bh.n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+      goto too_big;
     }
   }
-  return 1;
+  if( sqlite3VdbeMemGrow(pOut, u.bh.n, 0) ){
+    goto no_mem;
+  }
+  pOut->n = u.bh.n;
+  MemSetTypeFlag(pOut, MEM_Blob);
+  if( u.bh.pC->isIndex ){
+    rc = sqlite3BtreeKey(u.bh.pCrsr, 0, u.bh.n, pOut->z);
+  }else{
+    rc = sqlite3BtreeData(u.bh.pCrsr, 0, u.bh.n, pOut->z);
+  }
+  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
+  UPDATE_MAX_BLOBSIZE(pOut);
+  break;
 }
 
-/*
-** If pExpr is a constant expression that is appropriate for
-** factoring out of a loop, then evaluate the expression
-** into a register and convert the expression into a TK_REGISTER
-** expression.
+/* Opcode: Rowid P1 P2 * * *
+**
+** Store in register P2 an integer which is the key of the table entry that
+** P1 is currently point to.
+**
+** P1 can be either an ordinary table or a virtual table.  There used to
+** be a separate OP_VRowid opcode for use with virtual tables, but this
+** one opcode now works for both table types.
 */
-static int evalConstExpr(void *pArg, Expr *pExpr){
-  Parse *pParse = (Parse*)pArg;
-  switch( pExpr->op ){
-    case TK_REGISTER: {
-      return 1;
-    }
-    case TK_FUNCTION:
-    case TK_AGG_FUNCTION:
-    case TK_CONST_FUNC: {
-      /* The arguments to a function have a fixed destination.
-      ** Mark them this way to avoid generated unneeded OP_SCopy
-      ** instructions. 
-      */
-      ExprList *pList = pExpr->pList;
-      if( pList ){
-        int i = pList->nExpr;
-        struct ExprList_item *pItem = pList->a;
-        for(; i>0; i--, pItem++){
-          if( pItem->pExpr ) pItem->pExpr->flags |= EP_FixedDest;
-        }
-      }
-      break;
+case OP_Rowid: {                 /* out2-prerelease */
+#if 0  /* local variables moved into u.bi */
+  VdbeCursor *pC;
+  i64 v;
+  sqlite3_vtab *pVtab;
+  const sqlite3_module *pModule;
+#endif /* local variables moved into u.bi */
+
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bi.pC = p->apCsr[pOp->p1];
+  assert( u.bi.pC!=0 );
+  assert( u.bi.pC->pseudoTableReg==0 );
+  if( u.bi.pC->nullRow ){
+    /* Do nothing so that reg[P2] remains NULL */
+    break;
+  }else if( u.bi.pC->deferredMoveto ){
+    u.bi.v = u.bi.pC->movetoTarget;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  }else if( u.bi.pC->pVtabCursor ){
+    u.bi.pVtab = u.bi.pC->pVtabCursor->pVtab;
+    u.bi.pModule = u.bi.pVtab->pModule;
+    assert( u.bi.pModule->xRowid );
+    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+    rc = u.bi.pModule->xRowid(u.bi.pC->pVtabCursor, &u.bi.v);
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = u.bi.pVtab->zErrMsg;
+    u.bi.pVtab->zErrMsg = 0;
+    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+  }else{
+    assert( u.bi.pC->pCursor!=0 );
+    rc = sqlite3VdbeCursorMoveto(u.bi.pC);
+    if( rc ) goto abort_due_to_error;
+    if( u.bi.pC->rowidIsValid ){
+      u.bi.v = u.bi.pC->lastRowid;
+    }else{
+      rc = sqlite3BtreeKeySize(u.bi.pC->pCursor, &u.bi.v);
+      assert( rc==SQLITE_OK );  /* Always so because of CursorMoveto() above */
     }
   }
-  if( isAppropriateForFactoring(pExpr) ){
-    int r1 = ++pParse->nMem;
-    int r2;
-    r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
-    if( r1!=r2 ) sqlite3ReleaseTempReg(pParse, r1);
-    pExpr->iColumn = pExpr->op;
-    pExpr->op = TK_REGISTER;
-    pExpr->iTable = r2;
-    return 1;
-  }
-  return 0;
+  pOut->u.i = u.bi.v;
+  MemSetTypeFlag(pOut, MEM_Int);
+  break;
 }
 
-/*
-** Preevaluate constant subexpressions within pExpr and store the
-** results in registers.  Modify pExpr so that the constant subexpresions
-** are TK_REGISTER opcodes that refer to the precomputed values.
+/* Opcode: NullRow P1 * * * *
+**
+** Move the cursor P1 to a null row.  Any OP_Column operations
+** that occur while the cursor is on the null row will always
+** write a NULL.
 */
-SQLITE_PRIVATE void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
-   walkExprTree(pExpr, evalConstExpr, pParse);
-}
+case OP_NullRow: {
+#if 0  /* local variables moved into u.bj */
+  VdbeCursor *pC;
+#endif /* local variables moved into u.bj */
 
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bj.pC = p->apCsr[pOp->p1];
+  assert( u.bj.pC!=0 );
+  u.bj.pC->nullRow = 1;
+  u.bj.pC->rowidIsValid = 0;
+  if( u.bj.pC->pCursor ){
+    sqlite3BtreeClearCursor(u.bj.pC->pCursor);
+  }
+  break;
+}
 
-/*
-** Generate code that pushes the value of every element of the given
-** expression list into a sequence of registers beginning at target.
+/* Opcode: Last P1 P2 * * *
 **
-** Return the number of elements evaluated.
+** The next use of the Rowid or Column or Next instruction for P1 
+** will refer to the last entry in the database table or index.
+** If the table or index is empty and P2>0, then jump immediately to P2.
+** If P2 is 0 or if the table or index is not empty, fall through
+** to the following instruction.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeExprList(
-  Parse *pParse,     /* Parsing context */
-  ExprList *pList,   /* The expression list to be coded */
-  int target,        /* Where to write results */
-  int doHardCopy     /* Call sqlite3ExprHardCopy on each element if true */
-){
-  struct ExprList_item *pItem;
-  int i, n;
-  assert( pList!=0 || pParse->db->mallocFailed );
-  if( pList==0 ){
-    return 0;
+case OP_Last: {        /* jump */
+#if 0  /* local variables moved into u.bk */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int res;
+#endif /* local variables moved into u.bk */
+
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bk.pC = p->apCsr[pOp->p1];
+  assert( u.bk.pC!=0 );
+  u.bk.pCrsr = u.bk.pC->pCursor;
+  if( u.bk.pCrsr==0 ){
+    u.bk.res = 1;
+  }else{
+    rc = sqlite3BtreeLast(u.bk.pCrsr, &u.bk.res);
   }
-  assert( target>0 );
-  n = pList->nExpr;
-  for(pItem=pList->a, i=0; i<n; i++, pItem++){
-    sqlite3ExprCode(pParse, pItem->pExpr, target+i);
-    if( doHardCopy ) sqlite3ExprHardCopy(pParse, target, n);
+  u.bk.pC->nullRow = (u8)u.bk.res;
+  u.bk.pC->deferredMoveto = 0;
+  u.bk.pC->rowidIsValid = 0;
+  u.bk.pC->cacheStatus = CACHE_STALE;
+  if( pOp->p2>0 && u.bk.res ){
+    pc = pOp->p2 - 1;
   }
-  return n;
+  break;
 }
 
-/*
-** Generate code for a boolean expression such that a jump is made
-** to the label "dest" if the expression is true but execution
-** continues straight thru if the expression is false.
+
+/* Opcode: Sort P1 P2 * * *
 **
-** If the expression evaluates to NULL (neither true nor false), then
-** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL.
+** This opcode does exactly the same thing as OP_Rewind except that
+** it increments an undocumented global variable used for testing.
 **
-** This code depends on the fact that certain token values (ex: TK_EQ)
-** are the same as opcode values (ex: OP_Eq) that implement the corresponding
-** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in
-** the make process cause these values to align.  Assert()s in the code
-** below verify that the numbers are aligned correctly.
+** Sorting is accomplished by writing records into a sorting index,
+** then rewinding that index and playing it back from beginning to
+** end.  We use the OP_Sort opcode instead of OP_Rewind to do the
+** rewinding so that the global variable will be incremented and
+** regression tests can determine whether or not the optimizer is
+** correctly optimizing out sorts.
 */
-SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
-  Vdbe *v = pParse->pVdbe;
-  int op = 0;
-  int regFree1 = 0;
-  int regFree2 = 0;
-  int r1, r2;
-
-  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
-  if( v==0 || pExpr==0 ) return;
-  op = pExpr->op;
-  switch( op ){
-    case TK_AND: {
-      int d2 = sqlite3VdbeMakeLabel(v);
-      testcase( jumpIfNull==0 );
-      testcase( pParse->disableColCache==0 );
-      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
-      pParse->disableColCache++;
-      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
-      assert( pParse->disableColCache>0 );
-      pParse->disableColCache--;
-      sqlite3VdbeResolveLabel(v, d2);
-      break;
-    }
-    case TK_OR: {
-      testcase( jumpIfNull==0 );
-      testcase( pParse->disableColCache==0 );
-      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
-      pParse->disableColCache++;
-      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
-      assert( pParse->disableColCache>0 );
-      pParse->disableColCache--;
-      break;
-    }
-    case TK_NOT: {
-      testcase( jumpIfNull==0 );
-      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
-      break;
-    }
-    case TK_LT:
-    case TK_LE:
-    case TK_GT:
-    case TK_GE:
-    case TK_NE:
-    case TK_EQ: {
-      assert( TK_LT==OP_Lt );
-      assert( TK_LE==OP_Le );
-      assert( TK_GT==OP_Gt );
-      assert( TK_GE==OP_Ge );
-      assert( TK_EQ==OP_Eq );
-      assert( TK_NE==OP_Ne );
-      testcase( op==TK_LT );
-      testcase( op==TK_LE );
-      testcase( op==TK_GT );
-      testcase( op==TK_GE );
-      testcase( op==TK_EQ );
-      testcase( op==TK_NE );
-      testcase( jumpIfNull==0 );
-      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
-                                  pExpr->pRight, &r2, &regFree2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, dest, jumpIfNull);
-      testcase( regFree1==0 );
-      testcase( regFree2==0 );
-      break;
-    }
-    case TK_ISNULL:
-    case TK_NOTNULL: {
-      assert( TK_ISNULL==OP_IsNull );
-      assert( TK_NOTNULL==OP_NotNull );
-      testcase( op==TK_ISNULL );
-      testcase( op==TK_NOTNULL );
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      sqlite3VdbeAddOp2(v, op, r1, dest);
-      testcase( regFree1==0 );
-      break;
-    }
-    case TK_BETWEEN: {
-      /*    x BETWEEN y AND z
-      **
-      ** Is equivalent to 
-      **
-      **    x>=y AND x<=z
-      **
-      ** Code it as such, taking care to do the common subexpression
-      ** elementation of x.
-      */
-      Expr exprAnd;
-      Expr compLeft;
-      Expr compRight;
-      Expr exprX;
+case OP_Sort: {        /* jump */
+#ifdef SQLITE_TEST
+  sqlite3_sort_count++;
+  sqlite3_search_count--;
+#endif
+  p->aCounter[SQLITE_STMTSTATUS_SORT-1]++;
+  /* Fall through into OP_Rewind */
+}
+/* Opcode: Rewind P1 P2 * * *
+**
+** The next use of the Rowid or Column or Next instruction for P1 
+** will refer to the first entry in the database table or index.
+** If the table or index is empty and P2>0, then jump immediately to P2.
+** If P2 is 0 or if the table or index is not empty, fall through
+** to the following instruction.
+*/
+case OP_Rewind: {        /* jump */
+#if 0  /* local variables moved into u.bl */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int res;
+#endif /* local variables moved into u.bl */
 
-      exprX = *pExpr->pLeft;
-      exprAnd.op = TK_AND;
-      exprAnd.pLeft = &compLeft;
-      exprAnd.pRight = &compRight;
-      compLeft.op = TK_GE;
-      compLeft.pLeft = &exprX;
-      compLeft.pRight = pExpr->pList->a[0].pExpr;
-      compRight.op = TK_LE;
-      compRight.pLeft = &exprX;
-      compRight.pRight = pExpr->pList->a[1].pExpr;
-      exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
-      testcase( regFree1==0 );
-      exprX.op = TK_REGISTER;
-      testcase( jumpIfNull==0 );
-      sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
-      break;
-    }
-    default: {
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
-      sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
-      testcase( regFree1==0 );
-      testcase( jumpIfNull==0 );
-      break;
-    }
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bl.pC = p->apCsr[pOp->p1];
+  assert( u.bl.pC!=0 );
+  if( (u.bl.pCrsr = u.bl.pC->pCursor)!=0 ){
+    rc = sqlite3BtreeFirst(u.bl.pCrsr, &u.bl.res);
+    u.bl.pC->atFirst = u.bl.res==0 ?1:0;
+    u.bl.pC->deferredMoveto = 0;
+    u.bl.pC->cacheStatus = CACHE_STALE;
+    u.bl.pC->rowidIsValid = 0;
+  }else{
+    u.bl.res = 1;
   }
-  sqlite3ReleaseTempReg(pParse, regFree1);
-  sqlite3ReleaseTempReg(pParse, regFree2);  
+  u.bl.pC->nullRow = (u8)u.bl.res;
+  assert( pOp->p2>0 && pOp->p2<p->nOp );
+  if( u.bl.res ){
+    pc = pOp->p2 - 1;
+  }
+  break;
 }
 
-/*
-** Generate code for a boolean expression such that a jump is made
-** to the label "dest" if the expression is false but execution
-** continues straight thru if the expression is true.
+/* Opcode: Next P1 P2 * * *
 **
-** If the expression evaluates to NULL (neither true nor false) then
-** jump if jumpIfNull is SQLITE_JUMPIFNULL or fall through if jumpIfNull
-** is 0.
+** Advance cursor P1 so that it points to the next key/data pair in its
+** table or index.  If there are no more key/value pairs then fall through
+** to the following instruction.  But if the cursor advance was successful,
+** jump immediately to P2.
+**
+** The P1 cursor must be for a real table, not a pseudo-table.
+**
+** See also: Prev
 */
-SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
-  Vdbe *v = pParse->pVdbe;
-  int op = 0;
-  int regFree1 = 0;
-  int regFree2 = 0;
-  int r1, r2;
-
-  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
-  if( v==0 || pExpr==0 ) return;
-
-  /* The value of pExpr->op and op are related as follows:
-  **
-  **       pExpr->op            op
-  **       ---------          ----------
-  **       TK_ISNULL          OP_NotNull
-  **       TK_NOTNULL         OP_IsNull
-  **       TK_NE              OP_Eq
-  **       TK_EQ              OP_Ne
-  **       TK_GT              OP_Le
-  **       TK_LE              OP_Gt
-  **       TK_GE              OP_Lt
-  **       TK_LT              OP_Ge
-  **
-  ** For other values of pExpr->op, op is undefined and unused.
-  ** The value of TK_ and OP_ constants are arranged such that we
-  ** can compute the mapping above using the following expression.
-  ** Assert()s verify that the computation is correct.
-  */
-  op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);
-
-  /* Verify correct alignment of TK_ and OP_ constants
-  */
-  assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );
-  assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );
-  assert( pExpr->op!=TK_NE || op==OP_Eq );
-  assert( pExpr->op!=TK_EQ || op==OP_Ne );
-  assert( pExpr->op!=TK_LT || op==OP_Ge );
-  assert( pExpr->op!=TK_LE || op==OP_Gt );
-  assert( pExpr->op!=TK_GT || op==OP_Le );
-  assert( pExpr->op!=TK_GE || op==OP_Lt );
-
-  switch( pExpr->op ){
-    case TK_AND: {
-      testcase( jumpIfNull==0 );
-      testcase( pParse->disableColCache==0 );
-      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
-      pParse->disableColCache++;
-      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
-      assert( pParse->disableColCache>0 );
-      pParse->disableColCache--;
-      break;
-    }
-    case TK_OR: {
-      int d2 = sqlite3VdbeMakeLabel(v);
-      testcase( jumpIfNull==0 );
-      testcase( pParse->disableColCache==0 );
-      sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
-      pParse->disableColCache++;
-      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
-      assert( pParse->disableColCache>0 );
-      pParse->disableColCache--;
-      sqlite3VdbeResolveLabel(v, d2);
-      break;
-    }
-    case TK_NOT: {
-      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
-      break;
-    }
-    case TK_LT:
-    case TK_LE:
-    case TK_GT:
-    case TK_GE:
-    case TK_NE:
-    case TK_EQ: {
-      testcase( op==TK_LT );
-      testcase( op==TK_LE );
-      testcase( op==TK_GT );
-      testcase( op==TK_GE );
-      testcase( op==TK_EQ );
-      testcase( op==TK_NE );
-      testcase( jumpIfNull==0 );
-      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
-                                  pExpr->pRight, &r2, &regFree2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, dest, jumpIfNull);
-      testcase( regFree1==0 );
-      testcase( regFree2==0 );
-      break;
-    }
-    case TK_ISNULL:
-    case TK_NOTNULL: {
-      testcase( op==TK_ISNULL );
-      testcase( op==TK_NOTNULL );
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      sqlite3VdbeAddOp2(v, op, r1, dest);
-      testcase( regFree1==0 );
-      break;
-    }
-    case TK_BETWEEN: {
-      /*    x BETWEEN y AND z
-      **
-      ** Is equivalent to 
-      **
-      **    x>=y AND x<=z
-      **
-      ** Code it as such, taking care to do the common subexpression
-      ** elementation of x.
-      */
-      Expr exprAnd;
-      Expr compLeft;
-      Expr compRight;
-      Expr exprX;
+/* Opcode: Prev P1 P2 * * *
+**
+** Back up cursor P1 so that it points to the previous key/data pair in its
+** table or index.  If there is no previous key/value pairs then fall through
+** to the following instruction.  But if the cursor backup was successful,
+** jump immediately to P2.
+**
+** The P1 cursor must be for a real table, not a pseudo-table.
+*/
+case OP_Prev:          /* jump */
+case OP_Next: {        /* jump */
+#if 0  /* local variables moved into u.bm */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int res;
+#endif /* local variables moved into u.bm */
 
-      exprX = *pExpr->pLeft;
-      exprAnd.op = TK_AND;
-      exprAnd.pLeft = &compLeft;
-      exprAnd.pRight = &compRight;
-      compLeft.op = TK_GE;
-      compLeft.pLeft = &exprX;
-      compLeft.pRight = pExpr->pList->a[0].pExpr;
-      compRight.op = TK_LE;
-      compRight.pLeft = &exprX;
-      compRight.pRight = pExpr->pList->a[1].pExpr;
-      exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
-      testcase( regFree1==0 );
-      exprX.op = TK_REGISTER;
-      testcase( jumpIfNull==0 );
-      sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
-      break;
-    }
-    default: {
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
-      sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
-      testcase( regFree1==0 );
-      testcase( jumpIfNull==0 );
-      break;
-    }
+  CHECK_FOR_INTERRUPT;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bm.pC = p->apCsr[pOp->p1];
+  if( u.bm.pC==0 ){
+    break;  /* See ticket #2273 */
   }
-  sqlite3ReleaseTempReg(pParse, regFree1);
-  sqlite3ReleaseTempReg(pParse, regFree2);
+  u.bm.pCrsr = u.bm.pC->pCursor;
+  if( u.bm.pCrsr==0 ){
+    u.bm.pC->nullRow = 1;
+    break;
+  }
+  u.bm.res = 1;
+  assert( u.bm.pC->deferredMoveto==0 );
+  rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(u.bm.pCrsr, &u.bm.res) :
+                              sqlite3BtreePrevious(u.bm.pCrsr, &u.bm.res);
+  u.bm.pC->nullRow = (u8)u.bm.res;
+  u.bm.pC->cacheStatus = CACHE_STALE;
+  if( u.bm.res==0 ){
+    pc = pOp->p2 - 1;
+    if( pOp->p5 ) p->aCounter[pOp->p5-1]++;
+#ifdef SQLITE_TEST
+    sqlite3_search_count++;
+#endif
+  }
+  u.bm.pC->rowidIsValid = 0;
+  break;
 }
 
-/*
-** Do a deep comparison of two expression trees.  Return TRUE (non-zero)
-** if they are identical and return FALSE if they differ in any way.
+/* Opcode: IdxInsert P1 P2 P3 * P5
 **
-** Sometimes this routine will return FALSE even if the two expressions
-** really are equivalent.  If we cannot prove that the expressions are
-** identical, we return FALSE just to be safe.  So if this routine
-** returns false, then you do not really know for certain if the two
-** expressions are the same.  But if you get a TRUE return, then you
-** can be sure the expressions are the same.  In the places where
-** this routine is used, it does not hurt to get an extra FALSE - that
-** just might result in some slightly slower code.  But returning
-** an incorrect TRUE could lead to a malfunction.
+** Register P2 holds a SQL index key made using the
+** MakeRecord instructions.  This opcode writes that key
+** into the index P1.  Data for the entry is nil.
+**
+** P3 is a flag that provides a hint to the b-tree layer that this
+** insert is likely to be an append.
+**
+** This instruction only works for indices.  The equivalent instruction
+** for tables is OP_Insert.
 */
-SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
-  int i;
-  if( pA==0||pB==0 ){
-    return pB==pA;
-  }
-  if( pA->op!=pB->op ) return 0;
-  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0;
-  if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;
-  if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;
-  if( pA->pList ){
-    if( pB->pList==0 ) return 0;
-    if( pA->pList->nExpr!=pB->pList->nExpr ) return 0;
-    for(i=0; i<pA->pList->nExpr; i++){
-      if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){
-        return 0;
-      }
-    }
-  }else if( pB->pList ){
-    return 0;
-  }
-  if( pA->pSelect || pB->pSelect ) return 0;
-  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;
-  if( pA->op!=TK_COLUMN && pA->token.z ){
-    if( pB->token.z==0 ) return 0;
-    if( pB->token.n!=pA->token.n ) return 0;
-    if( sqlite3StrNICmp((char*)pA->token.z,(char*)pB->token.z,pB->token.n)!=0 ){
-      return 0;
+case OP_IdxInsert: {        /* in2 */
+#if 0  /* local variables moved into u.bn */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int nKey;
+  const char *zKey;
+#endif /* local variables moved into u.bn */
+
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bn.pC = p->apCsr[pOp->p1];
+  assert( u.bn.pC!=0 );
+  assert( pIn2->flags & MEM_Blob );
+  u.bn.pCrsr = u.bn.pC->pCursor;
+  if( ALWAYS(u.bn.pCrsr!=0) ){
+    assert( u.bn.pC->isTable==0 );
+    rc = ExpandBlob(pIn2);
+    if( rc==SQLITE_OK ){
+      u.bn.nKey = pIn2->n;
+      u.bn.zKey = pIn2->z;
+      rc = sqlite3BtreeInsert(u.bn.pCrsr, u.bn.zKey, u.bn.nKey, "", 0, 0, pOp->p3,
+          ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bn.pC->seekResult : 0)
+      );
+      assert( u.bn.pC->deferredMoveto==0 );
+      u.bn.pC->cacheStatus = CACHE_STALE;
     }
   }
-  return 1;
+  break;
 }
 
-
-/*
-** Add a new element to the pAggInfo->aCol[] array.  Return the index of
-** the new element.  Return a negative number if malloc fails.
+/* Opcode: IdxDelete P1 P2 P3 * *
+**
+** The content of P3 registers starting at register P2 form
+** an unpacked index key. This opcode removes that entry from the 
+** index opened by cursor P1.
 */
-static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){
-  int i;
-  pInfo->aCol = sqlite3ArrayAllocate(
-       db,
-       pInfo->aCol,
-       sizeof(pInfo->aCol[0]),
-       3,
-       &pInfo->nColumn,
-       &pInfo->nColumnAlloc,
-       &i
-  );
-  return i;
-}    
+case OP_IdxDelete: {
+#if 0  /* local variables moved into u.bo */
+  VdbeCursor *pC;
+  BtCursor *pCrsr;
+  int res;
+  UnpackedRecord r;
+#endif /* local variables moved into u.bo */
 
-/*
-** Add a new element to the pAggInfo->aFunc[] array.  Return the index of
-** the new element.  Return a negative number if malloc fails.
-*/
-static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){
-  int i;
-  pInfo->aFunc = sqlite3ArrayAllocate(
-       db, 
-       pInfo->aFunc,
-       sizeof(pInfo->aFunc[0]),
-       3,
-       &pInfo->nFunc,
-       &pInfo->nFuncAlloc,
-       &i
-  );
-  return i;
-}    
+  assert( pOp->p3>0 );
+  assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem+1 );
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bo.pC = p->apCsr[pOp->p1];
+  assert( u.bo.pC!=0 );
+  u.bo.pCrsr = u.bo.pC->pCursor;
+  if( ALWAYS(u.bo.pCrsr!=0) ){
+    u.bo.r.pKeyInfo = u.bo.pC->pKeyInfo;
+    u.bo.r.nField = (u16)pOp->p3;
+    u.bo.r.flags = 0;
+    u.bo.r.aMem = &p->aMem[pOp->p2];
+    rc = sqlite3BtreeMovetoUnpacked(u.bo.pCrsr, &u.bo.r, 0, 0, &u.bo.res);
+    if( rc==SQLITE_OK && u.bo.res==0 ){
+      rc = sqlite3BtreeDelete(u.bo.pCrsr);
+    }
+    assert( u.bo.pC->deferredMoveto==0 );
+    u.bo.pC->cacheStatus = CACHE_STALE;
+  }
+  break;
+}
 
-/*
-** This is an xFunc for walkExprTree() used to implement 
-** sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates
-** for additional information.
+/* Opcode: IdxRowid P1 P2 * * *
+**
+** Write into register P2 an integer which is the last entry in the record at
+** the end of the index key pointed to by cursor P1.  This integer should be
+** the rowid of the table entry to which this index entry points.
 **
-** This routine analyzes the aggregate function at pExpr.
+** See also: Rowid, MakeRecord.
 */
-static int analyzeAggregate(void *pArg, Expr *pExpr){
-  int i;
-  NameContext *pNC = (NameContext *)pArg;
-  Parse *pParse = pNC->pParse;
-  SrcList *pSrcList = pNC->pSrcList;
-  AggInfo *pAggInfo = pNC->pAggInfo;
+case OP_IdxRowid: {              /* out2-prerelease */
+#if 0  /* local variables moved into u.bp */
+  BtCursor *pCrsr;
+  VdbeCursor *pC;
+  i64 rowid;
+#endif /* local variables moved into u.bp */
 
-  switch( pExpr->op ){
-    case TK_AGG_COLUMN:
-    case TK_COLUMN: {
-      /* Check to see if the column is in one of the tables in the FROM
-      ** clause of the aggregate query */
-      if( pSrcList ){
-        struct SrcList_item *pItem = pSrcList->a;
-        for(i=0; i<pSrcList->nSrc; i++, pItem++){
-          struct AggInfo_col *pCol;
-          if( pExpr->iTable==pItem->iCursor ){
-            /* If we reach this point, it means that pExpr refers to a table
-            ** that is in the FROM clause of the aggregate query.  
-            **
-            ** Make an entry for the column in pAggInfo->aCol[] if there
-            ** is not an entry there already.
-            */
-            int k;
-            pCol = pAggInfo->aCol;
-            for(k=0; k<pAggInfo->nColumn; k++, pCol++){
-              if( pCol->iTable==pExpr->iTable &&
-                  pCol->iColumn==pExpr->iColumn ){
-                break;
-              }
-            }
-            if( (k>=pAggInfo->nColumn)
-             && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 
-            ){
-              pCol = &pAggInfo->aCol[k];
-              pCol->pTab = pExpr->pTab;
-              pCol->iTable = pExpr->iTable;
-              pCol->iColumn = pExpr->iColumn;
-              pCol->iMem = ++pParse->nMem;
-              pCol->iSorterColumn = -1;
-              pCol->pExpr = pExpr;
-              if( pAggInfo->pGroupBy ){
-                int j, n;
-                ExprList *pGB = pAggInfo->pGroupBy;
-                struct ExprList_item *pTerm = pGB->a;
-                n = pGB->nExpr;
-                for(j=0; j<n; j++, pTerm++){
-                  Expr *pE = pTerm->pExpr;
-                  if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable &&
-                      pE->iColumn==pExpr->iColumn ){
-                    pCol->iSorterColumn = j;
-                    break;
-                  }
-                }
-              }
-              if( pCol->iSorterColumn<0 ){
-                pCol->iSorterColumn = pAggInfo->nSortingColumn++;
-              }
-            }
-            /* There is now an entry for pExpr in pAggInfo->aCol[] (either
-            ** because it was there before or because we just created it).
-            ** Convert the pExpr to be a TK_AGG_COLUMN referring to that
-            ** pAggInfo->aCol[] entry.
-            */
-            pExpr->pAggInfo = pAggInfo;
-            pExpr->op = TK_AGG_COLUMN;
-            pExpr->iAgg = k;
-            break;
-          } /* endif pExpr->iTable==pItem->iCursor */
-        } /* end loop over pSrcList */
-      }
-      return 1;
-    }
-    case TK_AGG_FUNCTION: {
-      /* The pNC->nDepth==0 test causes aggregate functions in subqueries
-      ** to be ignored */
-      if( pNC->nDepth==0 ){
-        /* Check to see if pExpr is a duplicate of another aggregate 
-        ** function that is already in the pAggInfo structure
-        */
-        struct AggInfo_func *pItem = pAggInfo->aFunc;
-        for(i=0; i<pAggInfo->nFunc; i++, pItem++){
-          if( sqlite3ExprCompare(pItem->pExpr, pExpr) ){
-            break;
-          }
-        }
-        if( i>=pAggInfo->nFunc ){
-          /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]
-          */
-          u8 enc = ENC(pParse->db);
-          i = addAggInfoFunc(pParse->db, pAggInfo);
-          if( i>=0 ){
-            pItem = &pAggInfo->aFunc[i];
-            pItem->pExpr = pExpr;
-            pItem->iMem = ++pParse->nMem;
-            pItem->pFunc = sqlite3FindFunction(pParse->db,
-                   (char*)pExpr->token.z, pExpr->token.n,
-                   pExpr->pList ? pExpr->pList->nExpr : 0, enc, 0);
-            if( pExpr->flags & EP_Distinct ){
-              pItem->iDistinct = pParse->nTab++;
-            }else{
-              pItem->iDistinct = -1;
-            }
-          }
-        }
-        /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
-        */
-        pExpr->iAgg = i;
-        pExpr->pAggInfo = pAggInfo;
-        return 1;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bp.pC = p->apCsr[pOp->p1];
+  assert( u.bp.pC!=0 );
+  u.bp.pCrsr = u.bp.pC->pCursor;
+  if( ALWAYS(u.bp.pCrsr!=0) ){
+    rc = sqlite3VdbeCursorMoveto(u.bp.pC);
+    if( NEVER(rc) ) goto abort_due_to_error;
+    assert( u.bp.pC->deferredMoveto==0 );
+    assert( u.bp.pC->isTable==0 );
+    if( !u.bp.pC->nullRow ){
+      rc = sqlite3VdbeIdxRowid(db, u.bp.pCrsr, &u.bp.rowid);
+      if( rc!=SQLITE_OK ){
+        goto abort_due_to_error;
       }
+      MemSetTypeFlag(pOut, MEM_Int);
+      pOut->u.i = u.bp.rowid;
     }
   }
-
-  /* Recursively walk subqueries looking for TK_COLUMN nodes that need
-  ** to be changed to TK_AGG_COLUMN.  But increment nDepth so that
-  ** TK_AGG_FUNCTION nodes in subqueries will be unchanged.
-  */
-  if( pExpr->pSelect ){
-    pNC->nDepth++;
-    walkSelectExpr(pExpr->pSelect, analyzeAggregate, pNC);
-    pNC->nDepth--;
-  }
-  return 0;
+  break;
 }
 
-/*
-** Analyze the given expression looking for aggregate functions and
-** for variables that need to be added to the pParse->aAgg[] array.
-** Make additional entries to the pParse->aAgg[] array as necessary.
+/* Opcode: IdxGE P1 P2 P3 P4 P5
 **
-** This routine should only be called after the expression has been
-** analyzed by sqlite3ExprResolveNames().
+** The P4 register values beginning with P3 form an unpacked index 
+** key that omits the ROWID.  Compare this key value against the index 
+** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
+**
+** If the P1 index entry is greater than or equal to the key value
+** then jump to P2.  Otherwise fall through to the next instruction.
+**
+** If P5 is non-zero then the key value is increased by an epsilon 
+** prior to the comparison.  This make the opcode work like IdxGT except
+** that if the key from register P3 is a prefix of the key in the cursor,
+** the result is false whereas it would be true with IdxGT.
 */
-SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
-  walkExprTree(pExpr, analyzeAggregate, pNC);
-}
-
-/*
-** Call sqlite3ExprAnalyzeAggregates() for every expression in an
-** expression list.  Return the number of errors.
+/* Opcode: IdxLT P1 P2 P3 * P5
 **
-** If an error is found, the analysis is cut short.
+** The P4 register values beginning with P3 form an unpacked index 
+** key that omits the ROWID.  Compare this key value against the index 
+** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
+**
+** If the P1 index entry is less than the key value then jump to P2.
+** Otherwise fall through to the next instruction.
+**
+** If P5 is non-zero then the key value is increased by an epsilon prior 
+** to the comparison.  This makes the opcode work like IdxLE.
 */
-SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){
-  struct ExprList_item *pItem;
-  int i;
-  if( pList ){
-    for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
-      sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr);
+case OP_IdxLT:          /* jump, in3 */
+case OP_IdxGE: {        /* jump, in3 */
+#if 0  /* local variables moved into u.bq */
+  VdbeCursor *pC;
+  int res;
+  UnpackedRecord r;
+#endif /* local variables moved into u.bq */
+
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  u.bq.pC = p->apCsr[pOp->p1];
+  assert( u.bq.pC!=0 );
+  if( ALWAYS(u.bq.pC->pCursor!=0) ){
+    assert( u.bq.pC->deferredMoveto==0 );
+    assert( pOp->p5==0 || pOp->p5==1 );
+    assert( pOp->p4type==P4_INT32 );
+    u.bq.r.pKeyInfo = u.bq.pC->pKeyInfo;
+    u.bq.r.nField = (u16)pOp->p4.i;
+    if( pOp->p5 ){
+      u.bq.r.flags = UNPACKED_INCRKEY | UNPACKED_IGNORE_ROWID;
+    }else{
+      u.bq.r.flags = UNPACKED_IGNORE_ROWID;
+    }
+    u.bq.r.aMem = &p->aMem[pOp->p3];
+    rc = sqlite3VdbeIdxKeyCompare(u.bq.pC, &u.bq.r, &u.bq.res);
+    if( pOp->opcode==OP_IdxLT ){
+      u.bq.res = -u.bq.res;
+    }else{
+      assert( pOp->opcode==OP_IdxGE );
+      u.bq.res++;
+    }
+    if( u.bq.res>0 ){
+      pc = pOp->p2 - 1 ;
     }
   }
+  break;
 }
 
-/*
-** Allocate or deallocate temporary use registers during code generation.
+/* Opcode: Destroy P1 P2 P3 * *
+**
+** Delete an entire database table or index whose root page in the database
+** file is given by P1.
+**
+** The table being destroyed is in the main database file if P3==0.  If
+** P3==1 then the table to be clear is in the auxiliary database file
+** that is used to store tables create using CREATE TEMPORARY TABLE.
+**
+** If AUTOVACUUM is enabled then it is possible that another root page
+** might be moved into the newly deleted root page in order to keep all
+** root pages contiguous at the beginning of the database.  The former
+** value of the root page that moved - its value before the move occurred -
+** is stored in register P2.  If no page 
+** movement was required (because the table being dropped was already 
+** the last one in the database) then a zero is stored in register P2.
+** If AUTOVACUUM is disabled then a zero is stored in register P2.
+**
+** See also: Clear
 */
-SQLITE_PRIVATE int sqlite3GetTempReg(Parse *pParse){
-  int i, r;
-  if( pParse->nTempReg==0 ){
-    return ++pParse->nMem;
-  }
-  for(i=0; i<pParse->nTempReg; i++){
-    r = pParse->aTempReg[i];
-    if( usedAsColumnCache(pParse, r, r) ) continue;
-  }
-  if( i>=pParse->nTempReg ){
-    return ++pParse->nMem;
+case OP_Destroy: {     /* out2-prerelease */
+#if 0  /* local variables moved into u.br */
+  int iMoved;
+  int iCnt;
+  Vdbe *pVdbe;
+  int iDb;
+#endif /* local variables moved into u.br */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  u.br.iCnt = 0;
+  for(u.br.pVdbe=db->pVdbe; u.br.pVdbe; u.br.pVdbe = u.br.pVdbe->pNext){
+    if( u.br.pVdbe->magic==VDBE_MAGIC_RUN && u.br.pVdbe->inVtabMethod<2 && u.br.pVdbe->pc>=0 ){
+      u.br.iCnt++;
+    }
   }
-  while( i<pParse->nTempReg-1 ){
-    pParse->aTempReg[i] = pParse->aTempReg[i+1];
+#else
+  u.br.iCnt = db->activeVdbeCnt;
+#endif
+  if( u.br.iCnt>1 ){
+    rc = SQLITE_LOCKED;
+    p->errorAction = OE_Abort;
+  }else{
+    u.br.iDb = pOp->p3;
+    assert( u.br.iCnt==1 );
+    assert( (p->btreeMask & (1<<u.br.iDb))!=0 );
+    rc = sqlite3BtreeDropTable(db->aDb[u.br.iDb].pBt, pOp->p1, &u.br.iMoved);
+    MemSetTypeFlag(pOut, MEM_Int);
+    pOut->u.i = u.br.iMoved;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    if( rc==SQLITE_OK && u.br.iMoved!=0 ){
+      sqlite3RootPageMoved(&db->aDb[u.br.iDb], u.br.iMoved, pOp->p1);
+    }
+#endif
   }
-  pParse->nTempReg--;
-  return r;
+  break;
 }
-SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
-  if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){
-    pParse->aTempReg[pParse->nTempReg++] = iReg;
+
+/* Opcode: Clear P1 P2 P3
+**
+** Delete all contents of the database table or index whose root page
+** in the database file is given by P1.  But, unlike Destroy, do not
+** remove the table or index from the database file.
+**
+** The table being clear is in the main database file if P2==0.  If
+** P2==1 then the table to be clear is in the auxiliary database file
+** that is used to store tables create using CREATE TEMPORARY TABLE.
+**
+** If the P3 value is non-zero, then the table referred to must be an
+** intkey table (an SQL table, not an index). In this case the row change 
+** count is incremented by the number of rows in the table being cleared. 
+** If P3 is greater than zero, then the value stored in register P3 is
+** also incremented by the number of rows in the table being cleared.
+**
+** See also: Destroy
+*/
+case OP_Clear: {
+#if 0  /* local variables moved into u.bs */
+  int nChange;
+#endif /* local variables moved into u.bs */
+
+  u.bs.nChange = 0;
+  assert( (p->btreeMask & (1<<pOp->p2))!=0 );
+  rc = sqlite3BtreeClearTable(
+      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &u.bs.nChange : 0)
+  );
+  if( pOp->p3 ){
+    p->nChange += u.bs.nChange;
+    if( pOp->p3>0 ){
+      p->aMem[pOp->p3].u.i += u.bs.nChange;
+    }
   }
+  break;
 }
 
-/*
-** Allocate or deallocate a block of nReg consecutive registers
+/* Opcode: CreateTable P1 P2 * * *
+**
+** Allocate a new table in the main database file if P1==0 or in the
+** auxiliary database file if P1==1 or in an attached database if
+** P1>1.  Write the root page number of the new table into
+** register P2
+**
+** The difference between a table and an index is this:  A table must
+** have a 4-byte integer key and can have arbitrary data.  An index
+** has an arbitrary key but no data.
+**
+** See also: CreateIndex
 */
-SQLITE_PRIVATE int sqlite3GetTempRange(Parse *pParse, int nReg){
-  int i, n;
-  i = pParse->iRangeReg;
-  n = pParse->nRangeReg;
-  if( nReg<=n && !usedAsColumnCache(pParse, i, i+n-1) ){
-    pParse->iRangeReg += nReg;
-    pParse->nRangeReg -= nReg;
+/* Opcode: CreateIndex P1 P2 * * *
+**
+** Allocate a new index in the main database file if P1==0 or in the
+** auxiliary database file if P1==1 or in an attached database if
+** P1>1.  Write the root page number of the new table into
+** register P2.
+**
+** See documentation on OP_CreateTable for additional information.
+*/
+case OP_CreateIndex:            /* out2-prerelease */
+case OP_CreateTable: {          /* out2-prerelease */
+#if 0  /* local variables moved into u.bt */
+  int pgno;
+  int flags;
+  Db *pDb;
+#endif /* local variables moved into u.bt */
+
+  u.bt.pgno = 0;
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
+  u.bt.pDb = &db->aDb[pOp->p1];
+  assert( u.bt.pDb->pBt!=0 );
+  if( pOp->opcode==OP_CreateTable ){
+    /* u.bt.flags = BTREE_INTKEY; */
+    u.bt.flags = BTREE_LEAFDATA|BTREE_INTKEY;
   }else{
-    i = pParse->nMem+1;
-    pParse->nMem += nReg;
+    u.bt.flags = BTREE_ZERODATA;
   }
-  return i;
+  rc = sqlite3BtreeCreateTable(u.bt.pDb->pBt, &u.bt.pgno, u.bt.flags);
+  pOut->u.i = u.bt.pgno;
+  MemSetTypeFlag(pOut, MEM_Int);
+  break;
 }
-SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
-  if( nReg>pParse->nRangeReg ){
-    pParse->nRangeReg = nReg;
-    pParse->iRangeReg = iReg;
+
+/* Opcode: ParseSchema P1 P2 * P4 *
+**
+** Read and parse all entries from the SQLITE_MASTER table of database P1
+** that match the WHERE clause P4.  P2 is the "force" flag.   Always do
+** the parsing if P2 is true.  If P2 is false, then this routine is a
+** no-op if the schema is not currently loaded.  In other words, if P2
+** is false, the SQLITE_MASTER table is only parsed if the rest of the
+** schema is already loaded into the symbol table.
+**
+** This opcode invokes the parser to create a new virtual machine,
+** then runs the new virtual machine.  It is thus a re-entrant opcode.
+*/
+case OP_ParseSchema: {
+#if 0  /* local variables moved into u.bu */
+  int iDb;
+  const char *zMaster;
+  char *zSql;
+  InitData initData;
+#endif /* local variables moved into u.bu */
+
+  u.bu.iDb = pOp->p1;
+  assert( u.bu.iDb>=0 && u.bu.iDb<db->nDb );
+
+  /* If pOp->p2 is 0, then this opcode is being executed to read a
+  ** single row, for example the row corresponding to a new index
+  ** created by this VDBE, from the sqlite_master table. It only
+  ** does this if the corresponding in-memory schema is currently
+  ** loaded. Otherwise, the new index definition can be loaded along
+  ** with the rest of the schema when it is required.
+  **
+  ** Although the mutex on the BtShared object that corresponds to
+  ** database u.bu.iDb (the database containing the sqlite_master table
+  ** read by this instruction) is currently held, it is necessary to
+  ** obtain the mutexes on all attached databases before checking if
+  ** the schema of u.bu.iDb is loaded. This is because, at the start of
+  ** the sqlite3_exec() call below, SQLite will invoke
+  ** sqlite3BtreeEnterAll(). If all mutexes are not already held, the
+  ** u.bu.iDb mutex may be temporarily released to avoid deadlock. If
+  ** this happens, then some other thread may delete the in-memory
+  ** schema of database u.bu.iDb before the SQL statement runs. The schema
+  ** will not be reloaded becuase the db->init.busy flag is set. This
+  ** can result in a "no such table: sqlite_master" or "malformed
+  ** database schema" error being returned to the user.
+  */
+  assert( sqlite3BtreeHoldsMutex(db->aDb[u.bu.iDb].pBt) );
+  sqlite3BtreeEnterAll(db);
+  if( pOp->p2 || DbHasProperty(db, u.bu.iDb, DB_SchemaLoaded) ){
+    u.bu.zMaster = SCHEMA_TABLE(u.bu.iDb);
+    u.bu.initData.db = db;
+    u.bu.initData.iDb = pOp->p1;
+    u.bu.initData.pzErrMsg = &p->zErrMsg;
+    u.bu.zSql = sqlite3MPrintf(db,
+       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
+       db->aDb[u.bu.iDb].zName, u.bu.zMaster, pOp->p4.z);
+    if( u.bu.zSql==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      (void)sqlite3SafetyOff(db);
+      assert( db->init.busy==0 );
+      db->init.busy = 1;
+      u.bu.initData.rc = SQLITE_OK;
+      assert( !db->mallocFailed );
+      rc = sqlite3_exec(db, u.bu.zSql, sqlite3InitCallback, &u.bu.initData, 0);
+      if( rc==SQLITE_OK ) rc = u.bu.initData.rc;
+      sqlite3DbFree(db, u.bu.zSql);
+      db->init.busy = 0;
+      (void)sqlite3SafetyOn(db);
+    }
+  }
+  sqlite3BtreeLeaveAll(db);
+  if( rc==SQLITE_NOMEM ){
+    goto no_mem;
   }
+  break;
 }
 
-/************** End of expr.c ************************************************/
-/************** Begin file alter.c *******************************************/
-/*
-** 2005 February 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+#if !defined(SQLITE_OMIT_ANALYZE)
+/* Opcode: LoadAnalysis P1 * * * *
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Read the sqlite_stat1 table for database P1 and load the content
+** of that table into the internal index hash table.  This will cause
+** the analysis to be used when preparing all subsequent queries.
+*/
+case OP_LoadAnalysis: {
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  rc = sqlite3AnalysisLoad(db, pOp->p1);
+  break;  
+}
+#endif /* !defined(SQLITE_OMIT_ANALYZE) */
+
+/* Opcode: DropTable P1 * * P4 *
 **
-*************************************************************************
-** This file contains C code routines that used to generate VDBE code
-** that implements the ALTER TABLE command.
+** Remove the internal (in-memory) data structures that describe
+** the table named P4 in database P1.  This is called after a table
+** is dropped in order to keep the internal representation of the
+** schema consistent with what is on disk.
+*/
+case OP_DropTable: {
+  sqlite3UnlinkAndDeleteTable(db, pOp->p1, pOp->p4.z);
+  break;
+}
+
+/* Opcode: DropIndex P1 * * P4 *
 **
-** $Id: alter.c,v 1.44 2008/05/09 14:17:52 drh Exp $
+** Remove the internal (in-memory) data structures that describe
+** the index named P4 in database P1.  This is called after an index
+** is dropped in order to keep the internal representation of the
+** schema consistent with what is on disk.
 */
+case OP_DropIndex: {
+  sqlite3UnlinkAndDeleteIndex(db, pOp->p1, pOp->p4.z);
+  break;
+}
 
-/*
-** The code in this file only exists if we are not omitting the
-** ALTER TABLE logic from the build.
+/* Opcode: DropTrigger P1 * * P4 *
+**
+** Remove the internal (in-memory) data structures that describe
+** the trigger named P4 in database P1.  This is called after a trigger
+** is dropped in order to keep the internal representation of the
+** schema consistent with what is on disk.
 */
-#ifndef SQLITE_OMIT_ALTERTABLE
+case OP_DropTrigger: {
+  sqlite3UnlinkAndDeleteTrigger(db, pOp->p1, pOp->p4.z);
+  break;
+}
 
 
-/*
-** This function is used by SQL generated to implement the 
-** ALTER TABLE command. The first argument is the text of a CREATE TABLE or
-** CREATE INDEX command. The second is a table name. The table name in 
-** the CREATE TABLE or CREATE INDEX statement is replaced with the third
-** argument and the result returned. Examples:
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
+/* Opcode: IntegrityCk P1 P2 P3 * P5
 **
-** sqlite_rename_table('CREATE TABLE abc(a, b, c)', 'def')
-**     -> 'CREATE TABLE def(a, b, c)'
+** Do an analysis of the currently open database.  Store in
+** register P1 the text of an error message describing any problems.
+** If no problems are found, store a NULL in register P1.
 **
-** sqlite_rename_table('CREATE INDEX i ON abc(a)', 'def')
-**     -> 'CREATE INDEX i ON def(a, b, c)'
+** The register P3 contains the maximum number of allowed errors.
+** At most reg(P3) errors will be reported.
+** In other words, the analysis stops as soon as reg(P1) errors are 
+** seen.  Reg(P1) is updated with the number of errors remaining.
+**
+** The root page numbers of all tables in the database are integer
+** stored in reg(P1), reg(P1+1), reg(P1+2), ....  There are P2 tables
+** total.
+**
+** If P5 is not zero, the check is done on the auxiliary database
+** file, not the main database file.
+**
+** This opcode is used to implement the integrity_check pragma.
 */
-static void renameTableFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  unsigned char const *zSql = sqlite3_value_text(argv[0]);
-  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
-
-  int token;
-  Token tname;
-  unsigned char const *zCsr = zSql;
-  int len = 0;
-  char *zRet;
-
-  sqlite3 *db = sqlite3_context_db_handle(context);
-
-  /* The principle used to locate the table name in the CREATE TABLE 
-  ** statement is that the table name is the first non-space token that
-  ** is immediately followed by a left parenthesis - TK_LP - or "USING" TK_USING.
-  */
-  if( zSql ){
-    do {
-      if( !*zCsr ){
-        /* Ran out of input before finding an opening bracket. Return NULL. */
-        return;
-      }
+case OP_IntegrityCk: {
+#if 0  /* local variables moved into u.bv */
+  int nRoot;      /* Number of tables to check.  (Number of root pages.) */
+  int *aRoot;     /* Array of rootpage numbers for tables to be checked */
+  int j;          /* Loop counter */
+  int nErr;       /* Number of errors reported */
+  char *z;        /* Text of the error report */
+  Mem *pnErr;     /* Register keeping track of errors remaining */
+#endif /* local variables moved into u.bv */
 
-      /* Store the token that zCsr points to in tname. */
-      tname.z = zCsr;
-      tname.n = len;
+  u.bv.nRoot = pOp->p2;
+  assert( u.bv.nRoot>0 );
+  u.bv.aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(u.bv.nRoot+1) );
+  if( u.bv.aRoot==0 ) goto no_mem;
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  u.bv.pnErr = &p->aMem[pOp->p3];
+  assert( (u.bv.pnErr->flags & MEM_Int)!=0 );
+  assert( (u.bv.pnErr->flags & (MEM_Str|MEM_Blob))==0 );
+  pIn1 = &p->aMem[pOp->p1];
+  for(u.bv.j=0; u.bv.j<u.bv.nRoot; u.bv.j++){
+    u.bv.aRoot[u.bv.j] = (int)sqlite3VdbeIntValue(&pIn1[u.bv.j]);
+  }
+  u.bv.aRoot[u.bv.j] = 0;
+  assert( pOp->p5<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p5))!=0 );
+  u.bv.z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, u.bv.aRoot, u.bv.nRoot,
+                                 (int)u.bv.pnErr->u.i, &u.bv.nErr);
+  sqlite3DbFree(db, u.bv.aRoot);
+  u.bv.pnErr->u.i -= u.bv.nErr;
+  sqlite3VdbeMemSetNull(pIn1);
+  if( u.bv.nErr==0 ){
+    assert( u.bv.z==0 );
+  }else if( u.bv.z==0 ){
+    goto no_mem;
+  }else{
+    sqlite3VdbeMemSetStr(pIn1, u.bv.z, -1, SQLITE_UTF8, sqlite3_free);
+  }
+  UPDATE_MAX_BLOBSIZE(pIn1);
+  sqlite3VdbeChangeEncoding(pIn1, encoding);
+  break;
+}
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
 
-      /* Advance zCsr to the next token. Store that token type in 'token',
-      ** and its length in 'len' (to be used next iteration of this loop).
-      */
-      do {
-        zCsr += len;
-        len = sqlite3GetToken(zCsr, &token);
-      } while( token==TK_SPACE || token==TK_COMMENT );
-      assert( len>0 );
-    } while( token!=TK_LP && token!=TK_USING );
+/* Opcode: RowSetAdd P1 P2 * * *
+**
+** Insert the integer value held by register P2 into a boolean index
+** held in register P1.
+**
+** An assertion fails if P2 is not an integer.
+*/
+case OP_RowSetAdd: {       /* in2 */
+#if 0  /* local variables moved into u.bw */
+  Mem *pIdx;
+  Mem *pVal;
+#endif /* local variables moved into u.bw */
+  assert( pOp->p1>0 && pOp->p1<=p->nMem );
+  u.bw.pIdx = &p->aMem[pOp->p1];
+  assert( pOp->p2>0 && pOp->p2<=p->nMem );
+  u.bw.pVal = &p->aMem[pOp->p2];
+  assert( (u.bw.pVal->flags & MEM_Int)!=0 );
+  if( (u.bw.pIdx->flags & MEM_RowSet)==0 ){
+    sqlite3VdbeMemSetRowSet(u.bw.pIdx);
+    if( (u.bw.pIdx->flags & MEM_RowSet)==0 ) goto no_mem;
+  }
+  sqlite3RowSetInsert(u.bw.pIdx->u.pRowSet, u.bw.pVal->u.i);
+  break;
+}
 
-    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", tname.z - zSql, zSql, 
-       zTableName, tname.z+tname.n);
-    sqlite3_result_text(context, zRet, -1, sqlite3_free);
+/* Opcode: RowSetRead P1 P2 P3 * *
+**
+** Extract the smallest value from boolean index P1 and put that value into
+** register P3.  Or, if boolean index P1 is initially empty, leave P3
+** unchanged and jump to instruction P2.
+*/
+case OP_RowSetRead: {       /* jump, out3 */
+#if 0  /* local variables moved into u.bx */
+  Mem *pIdx;
+  i64 val;
+#endif /* local variables moved into u.bx */
+  assert( pOp->p1>0 && pOp->p1<=p->nMem );
+  CHECK_FOR_INTERRUPT;
+  u.bx.pIdx = &p->aMem[pOp->p1];
+  pOut = &p->aMem[pOp->p3];
+  if( (u.bx.pIdx->flags & MEM_RowSet)==0
+   || sqlite3RowSetNext(u.bx.pIdx->u.pRowSet, &u.bx.val)==0
+  ){
+    /* The boolean index is empty */
+    sqlite3VdbeMemSetNull(u.bx.pIdx);
+    pc = pOp->p2 - 1;
+  }else{
+    /* A value was pulled from the index */
+    assert( pOp->p3>0 && pOp->p3<=p->nMem );
+    sqlite3VdbeMemSetInt64(pOut, u.bx.val);
   }
+  break;
 }
 
-#ifndef SQLITE_OMIT_TRIGGER
-/* This function is used by SQL generated to implement the
-** ALTER TABLE command. The first argument is the text of a CREATE TRIGGER 
-** statement. The second is a table name. The table name in the CREATE 
-** TRIGGER statement is replaced with the third argument and the result 
-** returned. This is analagous to renameTableFunc() above, except for CREATE
-** TRIGGER, not CREATE INDEX and CREATE TABLE.
+/* Opcode: RowSetTest P1 P2 P3 P4
+**
+** Register P3 is assumed to hold a 64-bit integer value. If register P1
+** contains a RowSet object and that RowSet object contains
+** the value held in P3, jump to register P2. Otherwise, insert the
+** integer in P3 into the RowSet and continue on to the
+** next opcode.
+**
+** The RowSet object is optimized for the case where successive sets
+** of integers, where each set contains no duplicates. Each set
+** of values is identified by a unique P4 value. The first set
+** must have P4==0, the final set P4=-1.  P4 must be either -1 or
+** non-negative.  For non-negative values of P4 only the lower 4
+** bits are significant.
+**
+** This allows optimizations: (a) when P4==0 there is no need to test
+** the rowset object for P3, as it is guaranteed not to contain it,
+** (b) when P4==-1 there is no need to insert the value, as it will
+** never be tested for, and (c) when a value that is part of set X is
+** inserted, there is no need to search to see if the same value was
+** previously inserted as part of set X (only if it was previously
+** inserted as part of some other set).
 */
-static void renameTriggerFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  unsigned char const *zSql = sqlite3_value_text(argv[0]);
-  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
-
-  int token;
-  Token tname;
-  int dist = 3;
-  unsigned char const *zCsr = zSql;
-  int len = 0;
-  char *zRet;
+case OP_RowSetTest: {                     /* jump, in1, in3 */
+#if 0  /* local variables moved into u.by */
+  int iSet;
+  int exists;
+#endif /* local variables moved into u.by */
 
-  sqlite3 *db = sqlite3_context_db_handle(context);
+  u.by.iSet = pOp->p4.i;
+  assert( pIn3->flags&MEM_Int );
 
-  /* The principle used to locate the table name in the CREATE TRIGGER 
-  ** statement is that the table name is the first token that is immediatedly
-  ** preceded by either TK_ON or TK_DOT and immediatedly followed by one
-  ** of TK_WHEN, TK_BEGIN or TK_FOR.
+  /* If there is anything other than a rowset object in memory cell P1,
+  ** delete it now and initialize P1 with an empty rowset
   */
-  if( zSql ){
-    do {
+  if( (pIn1->flags & MEM_RowSet)==0 ){
+    sqlite3VdbeMemSetRowSet(pIn1);
+    if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem;
+  }
 
-      if( !*zCsr ){
-        /* Ran out of input before finding the table name. Return NULL. */
-        return;
-      }
+  assert( pOp->p4type==P4_INT32 );
+  assert( u.by.iSet==-1 || u.by.iSet>=0 );
+  if( u.by.iSet ){
+    u.by.exists = sqlite3RowSetTest(pIn1->u.pRowSet,
+                               (u8)(u.by.iSet>=0 ? u.by.iSet & 0xf : 0xff),
+                               pIn3->u.i);
+    if( u.by.exists ){
+      pc = pOp->p2 - 1;
+      break;
+    }
+  }
+  if( u.by.iSet>=0 ){
+    sqlite3RowSetInsert(pIn1->u.pRowSet, pIn3->u.i);
+  }
+  break;
+}
 
-      /* Store the token that zCsr points to in tname. */
-      tname.z = zCsr;
-      tname.n = len;
 
-      /* Advance zCsr to the next token. Store that token type in 'token',
-      ** and its length in 'len' (to be used next iteration of this loop).
-      */
-      do {
-        zCsr += len;
-        len = sqlite3GetToken(zCsr, &token);
-      }while( token==TK_SPACE );
-      assert( len>0 );
+#ifndef SQLITE_OMIT_TRIGGER
 
-      /* Variable 'dist' stores the number of tokens read since the most
-      ** recent TK_DOT or TK_ON. This means that when a WHEN, FOR or BEGIN 
-      ** token is read and 'dist' equals 2, the condition stated above
-      ** to be met.
-      **
-      ** Note that ON cannot be a database, table or column name, so
-      ** there is no need to worry about syntax like 
-      ** "CREATE TRIGGER ... ON ON.ON BEGIN ..." etc.
-      */
-      dist++;
-      if( token==TK_DOT || token==TK_ON ){
-        dist = 0;
-      }
-    } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );
+/* Opcode: Program P1 P2 P3 P4 *
+**
+** Execute the trigger program passed as P4 (type P4_SUBPROGRAM). 
+**
+** P1 contains the address of the memory cell that contains the first memory 
+** cell in an array of values used as arguments to the sub-program. P2 
+** contains the address to jump to if the sub-program throws an IGNORE 
+** exception using the RAISE() function. Register P3 contains the address 
+** of a memory cell in this (the parent) VM that is used to allocate the 
+** memory required by the sub-vdbe at runtime.
+**
+** P4 is a pointer to the VM containing the trigger program.
+*/
+case OP_Program: {        /* jump */
+#if 0  /* local variables moved into u.bz */
+  int nMem;               /* Number of memory registers for sub-program */
+  int nByte;              /* Bytes of runtime space required for sub-program */
+  Mem *pRt;               /* Register to allocate runtime space */
+  Mem *pMem;              /* Used to iterate through memory cells */
+  Mem *pEnd;              /* Last memory cell in new array */
+  VdbeFrame *pFrame;      /* New vdbe frame to execute in */
+  SubProgram *pProgram;   /* Sub-program to execute */
+  void *t;                /* Token identifying trigger */
+#endif /* local variables moved into u.bz */
+
+  u.bz.pProgram = pOp->p4.pProgram;
+  u.bz.pRt = &p->aMem[pOp->p3];
+  assert( u.bz.pProgram->nOp>0 );
+
+  /* If the p5 flag is clear, then recursive invocation of triggers is
+  ** disabled for backwards compatibility (p5 is set if this sub-program
+  ** is really a trigger, not a foreign key action, and the flag set
+  ** and cleared by the "PRAGMA recursive_triggers" command is clear).
+  **
+  ** It is recursive invocation of triggers, at the SQL level, that is
+  ** disabled. In some cases a single trigger may generate more than one
+  ** SubProgram (if the trigger may be executed with more than one different
+  ** ON CONFLICT algorithm). SubProgram structures associated with a
+  ** single trigger all have the same value for the SubProgram.token
+  ** variable.  */
+  if( pOp->p5 ){
+    u.bz.t = u.bz.pProgram->token;
+    for(u.bz.pFrame=p->pFrame; u.bz.pFrame && u.bz.pFrame->token!=u.bz.t; u.bz.pFrame=u.bz.pFrame->pParent);
+    if( u.bz.pFrame ) break;
+  }
 
-    /* Variable tname now contains the token that is the old table-name
-    ** in the CREATE TRIGGER statement.
+  if( p->nFrame>=db->aLimit[SQLITE_LIMIT_TRIGGER_DEPTH] ){
+    rc = SQLITE_ERROR;
+    sqlite3SetString(&p->zErrMsg, db, "too many levels of trigger recursion");
+    break;
+  }
+
+  /* Register u.bz.pRt is used to store the memory required to save the state
+  ** of the current program, and the memory required at runtime to execute
+  ** the trigger program. If this trigger has been fired before, then u.bz.pRt
+  ** is already allocated. Otherwise, it must be initialized.  */
+  if( (u.bz.pRt->flags&MEM_Frame)==0 ){
+    /* SubProgram.nMem is set to the number of memory cells used by the
+    ** program stored in SubProgram.aOp. As well as these, one memory
+    ** cell is required for each cursor used by the program. Set local
+    ** variable u.bz.nMem (and later, VdbeFrame.nChildMem) to this value.
     */
-    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", tname.z - zSql, zSql, 
-       zTableName, tname.z+tname.n);
-    sqlite3_result_text(context, zRet, -1, sqlite3_free);
+    u.bz.nMem = u.bz.pProgram->nMem + u.bz.pProgram->nCsr;
+    u.bz.nByte = ROUND8(sizeof(VdbeFrame))
+              + u.bz.nMem * sizeof(Mem)
+              + u.bz.pProgram->nCsr * sizeof(VdbeCursor *);
+    u.bz.pFrame = sqlite3DbMallocZero(db, u.bz.nByte);
+    if( !u.bz.pFrame ){
+      goto no_mem;
+    }
+    sqlite3VdbeMemRelease(u.bz.pRt);
+    u.bz.pRt->flags = MEM_Frame;
+    u.bz.pRt->u.pFrame = u.bz.pFrame;
+
+    u.bz.pFrame->v = p;
+    u.bz.pFrame->nChildMem = u.bz.nMem;
+    u.bz.pFrame->nChildCsr = u.bz.pProgram->nCsr;
+    u.bz.pFrame->pc = pc;
+    u.bz.pFrame->aMem = p->aMem;
+    u.bz.pFrame->nMem = p->nMem;
+    u.bz.pFrame->apCsr = p->apCsr;
+    u.bz.pFrame->nCursor = p->nCursor;
+    u.bz.pFrame->aOp = p->aOp;
+    u.bz.pFrame->nOp = p->nOp;
+    u.bz.pFrame->token = u.bz.pProgram->token;
+
+    u.bz.pEnd = &VdbeFrameMem(u.bz.pFrame)[u.bz.pFrame->nChildMem];
+    for(u.bz.pMem=VdbeFrameMem(u.bz.pFrame); u.bz.pMem!=u.bz.pEnd; u.bz.pMem++){
+      u.bz.pMem->flags = MEM_Null;
+      u.bz.pMem->db = db;
+    }
+  }else{
+    u.bz.pFrame = u.bz.pRt->u.pFrame;
+    assert( u.bz.pProgram->nMem+u.bz.pProgram->nCsr==u.bz.pFrame->nChildMem );
+    assert( u.bz.pProgram->nCsr==u.bz.pFrame->nChildCsr );
+    assert( pc==u.bz.pFrame->pc );
   }
+
+  p->nFrame++;
+  u.bz.pFrame->pParent = p->pFrame;
+  u.bz.pFrame->lastRowid = db->lastRowid;
+  u.bz.pFrame->nChange = p->nChange;
+  p->nChange = 0;
+  p->pFrame = u.bz.pFrame;
+  p->aMem = &VdbeFrameMem(u.bz.pFrame)[-1];
+  p->nMem = u.bz.pFrame->nChildMem;
+  p->nCursor = (u16)u.bz.pFrame->nChildCsr;
+  p->apCsr = (VdbeCursor **)&p->aMem[p->nMem+1];
+  p->aOp = u.bz.pProgram->aOp;
+  p->nOp = u.bz.pProgram->nOp;
+  pc = -1;
+
+  break;
 }
-#endif   /* !SQLITE_OMIT_TRIGGER */
 
-/*
-** Register built-in functions used to help implement ALTER TABLE
+/* Opcode: Param P1 P2 * * *
+**
+** This opcode is only ever present in sub-programs called via the 
+** OP_Program instruction. Copy a value currently stored in a memory 
+** cell of the calling (parent) frame to cell P2 in the current frames 
+** address space. This is used by trigger programs to access the new.* 
+** and old.* values.
+**
+** The address of the cell in the parent frame is determined by adding
+** the value of the P1 argument to the value of the P1 argument to the
+** calling OP_Program instruction.
 */
-SQLITE_PRIVATE void sqlite3AlterFunctions(sqlite3 *db){
-  static const struct {
-     char *zName;
-     signed char nArg;
-     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
-  } aFuncs[] = {
-    { "sqlite_rename_table",    2, renameTableFunc},
-#ifndef SQLITE_OMIT_TRIGGER
-    { "sqlite_rename_trigger",  2, renameTriggerFunc},
-#endif
-  };
-  int i;
+case OP_Param: {           /* out2-prerelease */
+#if 0  /* local variables moved into u.ca */
+  VdbeFrame *pFrame;
+  Mem *pIn;
+#endif /* local variables moved into u.ca */
+  u.ca.pFrame = p->pFrame;
+  u.ca.pIn = &u.ca.pFrame->aMem[pOp->p1 + u.ca.pFrame->aOp[u.ca.pFrame->pc].p1];
+  sqlite3VdbeMemShallowCopy(pOut, u.ca.pIn, MEM_Ephem);
+  break;
+}
 
-  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
-    sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
-        SQLITE_UTF8, 0, aFuncs[i].xFunc, 0, 0);
+#endif /* #ifndef SQLITE_OMIT_TRIGGER */
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+/* Opcode: FkCounter P1 P2 * * *
+**
+** Increment a "constraint counter" by P2 (P2 may be negative or positive).
+** If P1 is non-zero, the database constraint counter is incremented 
+** (deferred foreign key constraints). Otherwise, if P1 is zero, the 
+** statement counter is incremented (immediate foreign key constraints).
+*/
+case OP_FkCounter: {
+  if( pOp->p1 ){
+    db->nDeferredCons += pOp->p2;
+  }else{
+    p->nFkConstraint += pOp->p2;
   }
+  break;
 }
 
-/*
-** Generate the text of a WHERE expression which can be used to select all
-** temporary triggers on table pTab from the sqlite_temp_master table. If
-** table pTab has no temporary triggers, or is itself stored in the 
-** temporary database, NULL is returned.
+/* Opcode: FkIfZero P1 P2 * * *
+**
+** This opcode tests if a foreign key constraint-counter is currently zero.
+** If so, jump to instruction P2. Otherwise, fall through to the next 
+** instruction.
+**
+** If P1 is non-zero, then the jump is taken if the database constraint-counter
+** is zero (the one that counts deferred constraint violations). If P1 is
+** zero, the jump is taken if the statement constraint-counter is zero
+** (immediate foreign key constraint violations).
 */
-static char *whereTempTriggers(Parse *pParse, Table *pTab){
-  Trigger *pTrig;
-  char *zWhere = 0;
-  char *tmp = 0;
-  const Schema *pTempSchema = pParse->db->aDb[1].pSchema; /* Temp db schema */
-
-  /* If the table is not located in the temp-db (in which case NULL is 
-  ** returned, loop through the tables list of triggers. For each trigger
-  ** that is not part of the temp-db schema, add a clause to the WHERE 
-  ** expression being built up in zWhere.
-  */
-  if( pTab->pSchema!=pTempSchema ){
-    sqlite3 *db = pParse->db;
-    for( pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext ){
-      if( pTrig->pSchema==pTempSchema ){
-        if( !zWhere ){
-          zWhere = sqlite3MPrintf(db, "name=%Q", pTrig->name);
-        }else{
-          tmp = zWhere;
-          zWhere = sqlite3MPrintf(db, "%s OR name=%Q", zWhere, pTrig->name);
-          sqlite3_free(tmp);
-        }
-      }
-    }
+case OP_FkIfZero: {         /* jump */
+  if( pOp->p1 ){
+    if( db->nDeferredCons==0 ) pc = pOp->p2-1;
+  }else{
+    if( p->nFkConstraint==0 ) pc = pOp->p2-1;
   }
-  return zWhere;
+  break;
 }
+#endif /* #ifndef SQLITE_OMIT_FOREIGN_KEY */
 
-/*
-** Generate code to drop and reload the internal representation of table
-** pTab from the database, including triggers and temporary triggers.
-** Argument zName is the name of the table in the database schema at
-** the time the generated code is executed. This can be different from
-** pTab->zName if this function is being called to code part of an 
-** "ALTER TABLE RENAME TO" statement.
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+/* Opcode: MemMax P1 P2 * * *
+**
+** P1 is a register in the root frame of this VM (the root frame is
+** different from the current frame if this instruction is being executed
+** within a sub-program). Set the value of register P1 to the maximum of 
+** its current value and the value in register P2.
+**
+** This instruction throws an error if the memory cell is not initially
+** an integer.
 */
-static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
-  Vdbe *v;
-  char *zWhere;
-  int iDb;                   /* Index of database containing pTab */
-#ifndef SQLITE_OMIT_TRIGGER
-  Trigger *pTrig;
-#endif
-
-  v = sqlite3GetVdbe(pParse);
-  if( !v ) return;
-  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  assert( iDb>=0 );
-
-#ifndef SQLITE_OMIT_TRIGGER
-  /* Drop any table triggers from the internal schema. */
-  for(pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext){
-    int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
-    assert( iTrigDb==iDb || iTrigDb==1 );
-    sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->name, 0);
+case OP_MemMax: {        /* in2 */
+#if 0  /* local variables moved into u.cb */
+  Mem *pIn1;
+  VdbeFrame *pFrame;
+#endif /* local variables moved into u.cb */
+  if( p->pFrame ){
+    for(u.cb.pFrame=p->pFrame; u.cb.pFrame->pParent; u.cb.pFrame=u.cb.pFrame->pParent);
+    u.cb.pIn1 = &u.cb.pFrame->aMem[pOp->p1];
+  }else{
+    u.cb.pIn1 = &p->aMem[pOp->p1];
   }
-#endif
-
-  /* Drop the table and index from the internal schema */
-  sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
-
-  /* Reload the table, index and permanent trigger schemas. */
-  zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
-  if( !zWhere ) return;
-  sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);
-
-#ifndef SQLITE_OMIT_TRIGGER
-  /* Now, if the table is not stored in the temp database, reload any temp 
-  ** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined. 
-  */
-  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
-    sqlite3VdbeAddOp4(v, OP_ParseSchema, 1, 0, 0, zWhere, P4_DYNAMIC);
+  sqlite3VdbeMemIntegerify(u.cb.pIn1);
+  sqlite3VdbeMemIntegerify(pIn2);
+  if( u.cb.pIn1->u.i<pIn2->u.i){
+    u.cb.pIn1->u.i = pIn2->u.i;
   }
-#endif
+  break;
 }
+#endif /* SQLITE_OMIT_AUTOINCREMENT */
 
-/*
-** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
-** command. 
+/* Opcode: IfPos P1 P2 * * *
+**
+** If the value of register P1 is 1 or greater, jump to P2.
+**
+** It is illegal to use this instruction on a register that does
+** not contain an integer.  An assertion fault will result if you try.
 */
-SQLITE_PRIVATE void sqlite3AlterRenameTable(
-  Parse *pParse,            /* Parser context. */
-  SrcList *pSrc,            /* The table to rename. */
-  Token *pName              /* The new table name. */
-){
-  int iDb;                  /* Database that contains the table */
-  char *zDb;                /* Name of database iDb */
-  Table *pTab;              /* Table being renamed */
-  char *zName = 0;          /* NULL-terminated version of pName */ 
-  sqlite3 *db = pParse->db; /* Database connection */
-  int nTabName;             /* Number of UTF-8 characters in zTabName */
-  const char *zTabName;     /* Original name of the table */
-  Vdbe *v;
-#ifndef SQLITE_OMIT_TRIGGER
-  char *zWhere = 0;         /* Where clause to locate temp triggers */
-#endif
-  int isVirtualRename = 0;  /* True if this is a v-table with an xRename() */
-  
-  if( db->mallocFailed ) goto exit_rename_table;
-  assert( pSrc->nSrc==1 );
-  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-
-  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
-  if( !pTab ) goto exit_rename_table;
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  zDb = db->aDb[iDb].zName;
-
-  /* Get a NULL terminated version of the new table name. */
-  zName = sqlite3NameFromToken(db, pName);
-  if( !zName ) goto exit_rename_table;
-
-  /* Check that a table or index named 'zName' does not already exist
-  ** in database iDb. If so, this is an error.
-  */
-  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
-    sqlite3ErrorMsg(pParse, 
-        "there is already another table or index with this name: %s", zName);
-    goto exit_rename_table;
-  }
-
-  /* Make sure it is not a system table being altered, or a reserved name
-  ** that the table is being renamed to.
-  */
-  if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
-    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
-    goto exit_rename_table;
-  }
-  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
-    goto exit_rename_table;
+case OP_IfPos: {        /* jump, in1 */
+  assert( pIn1->flags&MEM_Int );
+  if( pIn1->u.i>0 ){
+     pc = pOp->p2 - 1;
   }
+  break;
+}
 
-#ifndef SQLITE_OMIT_VIEW
-  if( pTab->pSelect ){
-    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
-    goto exit_rename_table;
+/* Opcode: IfNeg P1 P2 * * *
+**
+** If the value of register P1 is less than zero, jump to P2. 
+**
+** It is illegal to use this instruction on a register that does
+** not contain an integer.  An assertion fault will result if you try.
+*/
+case OP_IfNeg: {        /* jump, in1 */
+  assert( pIn1->flags&MEM_Int );
+  if( pIn1->u.i<0 ){
+     pc = pOp->p2 - 1;
   }
-#endif
+  break;
+}
 
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  /* Invoke the authorization callback. */
-  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
-    goto exit_rename_table;
+/* Opcode: IfZero P1 P2 * * *
+**
+** If the value of register P1 is exactly 0, jump to P2. 
+**
+** It is illegal to use this instruction on a register that does
+** not contain an integer.  An assertion fault will result if you try.
+*/
+case OP_IfZero: {        /* jump, in1 */
+  assert( pIn1->flags&MEM_Int );
+  if( pIn1->u.i==0 ){
+     pc = pOp->p2 - 1;
   }
-#endif
+  break;
+}
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-    goto exit_rename_table;
+/* Opcode: AggStep * P2 P3 P4 P5
+**
+** Execute the step function for an aggregate.  The
+** function has P5 arguments.   P4 is a pointer to the FuncDef
+** structure that specifies the function.  Use register
+** P3 as the accumulator.
+**
+** The P5 arguments are taken from register P2 and its
+** successors.
+*/
+case OP_AggStep: {
+#if 0  /* local variables moved into u.cc */
+  int n;
+  int i;
+  Mem *pMem;
+  Mem *pRec;
+  sqlite3_context ctx;
+  sqlite3_value **apVal;
+#endif /* local variables moved into u.cc */
+
+  u.cc.n = pOp->p5;
+  assert( u.cc.n>=0 );
+  u.cc.pRec = &p->aMem[pOp->p2];
+  u.cc.apVal = p->apArg;
+  assert( u.cc.apVal || u.cc.n==0 );
+  for(u.cc.i=0; u.cc.i<u.cc.n; u.cc.i++, u.cc.pRec++){
+    u.cc.apVal[u.cc.i] = u.cc.pRec;
+    storeTypeInfo(u.cc.pRec, encoding);
+  }
+  u.cc.ctx.pFunc = pOp->p4.pFunc;
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  u.cc.ctx.pMem = u.cc.pMem = &p->aMem[pOp->p3];
+  u.cc.pMem->n++;
+  u.cc.ctx.s.flags = MEM_Null;
+  u.cc.ctx.s.z = 0;
+  u.cc.ctx.s.zMalloc = 0;
+  u.cc.ctx.s.xDel = 0;
+  u.cc.ctx.s.db = db;
+  u.cc.ctx.isError = 0;
+  u.cc.ctx.pColl = 0;
+  if( u.cc.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
+    assert( pOp>p->aOp );
+    assert( pOp[-1].p4type==P4_COLLSEQ );
+    assert( pOp[-1].opcode==OP_CollSeq );
+    u.cc.ctx.pColl = pOp[-1].p4.pColl;
   }
-  if( IsVirtual(pTab) && pTab->pMod->pModule->xRename ){
-    isVirtualRename = 1;
+  (u.cc.ctx.pFunc->xStep)(&u.cc.ctx, u.cc.n, u.cc.apVal);
+  if( u.cc.ctx.isError ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.cc.ctx.s));
+    rc = u.cc.ctx.isError;
   }
-#endif
+  sqlite3VdbeMemRelease(&u.cc.ctx.s);
+  break;
+}
 
-  /* Begin a transaction and code the VerifyCookie for database iDb. 
-  ** Then modify the schema cookie (since the ALTER TABLE modifies the
-  ** schema). Open a statement transaction if the table is a virtual
-  ** table.
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ){
-    goto exit_rename_table;
+/* Opcode: AggFinal P1 P2 * P4 *
+**
+** Execute the finalizer function for an aggregate.  P1 is
+** the memory location that is the accumulator for the aggregate.
+**
+** P2 is the number of arguments that the step function takes and
+** P4 is a pointer to the FuncDef for this function.  The P2
+** argument is not used by this opcode.  It is only there to disambiguate
+** functions that can take varying numbers of arguments.  The
+** P4 argument is only needed for the degenerate case where
+** the step function was not previously called.
+*/
+case OP_AggFinal: {
+#if 0  /* local variables moved into u.cd */
+  Mem *pMem;
+#endif /* local variables moved into u.cd */
+  assert( pOp->p1>0 && pOp->p1<=p->nMem );
+  u.cd.pMem = &p->aMem[pOp->p1];
+  assert( (u.cd.pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
+  rc = sqlite3VdbeMemFinalize(u.cd.pMem, pOp->p4.pFunc);
+  if( rc ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(u.cd.pMem));
   }
-  sqlite3BeginWriteOperation(pParse, isVirtualRename, iDb);
-  sqlite3ChangeCookie(pParse, iDb);
-
-  /* If this is a virtual table, invoke the xRename() function if
-  ** one is defined. The xRename() callback will modify the names
-  ** of any resources used by the v-table implementation (including other
-  ** SQLite tables) that are identified by the name of the virtual table.
-  */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( isVirtualRename ){
-    int i = ++pParse->nMem;
-    sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
-    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pTab->pVtab, P4_VTAB);
+  sqlite3VdbeChangeEncoding(u.cd.pMem, encoding);
+  UPDATE_MAX_BLOBSIZE(u.cd.pMem);
+  if( sqlite3VdbeMemTooBig(u.cd.pMem) ){
+    goto too_big;
   }
-#endif
+  break;
+}
 
-  /* figure out how many UTF-8 characters are in zName */
-  zTabName = pTab->zName;
-  nTabName = sqlite3Utf8CharLen(zTabName, -1);
 
-  /* Modify the sqlite_master table to use the new table name. */
-  sqlite3NestedParse(pParse,
-      "UPDATE %Q.%s SET "
-#ifdef SQLITE_OMIT_TRIGGER
-          "sql = sqlite_rename_table(sql, %Q), "
-#else
-          "sql = CASE "
-            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
-            "ELSE sqlite_rename_table(sql, %Q) END, "
-#endif
-          "tbl_name = %Q, "
-          "name = CASE "
-            "WHEN type='table' THEN %Q "
-            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
-             "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
-            "ELSE name END "
-      "WHERE tbl_name=%Q AND "
-          "(type='table' OR type='index' OR type='trigger');", 
-      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
-#ifndef SQLITE_OMIT_TRIGGER
-      zName,
+#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
+/* Opcode: Vacuum * * * * *
+**
+** Vacuum the entire database.  This opcode will cause other virtual
+** machines to be created and run.  It may not be called from within
+** a transaction.
+*/
+case OP_Vacuum: {
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse; 
+  rc = sqlite3RunVacuum(&p->zErrMsg, db);
+  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+  break;
+}
 #endif
-      zName, nTabName, zTabName
-  );
 
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-  /* If the sqlite_sequence table exists in this database, then update 
-  ** it with the new table name.
-  */
-  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
-    sqlite3NestedParse(pParse,
-        "UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
-        zDb, zName, pTab->zName);
-  }
-#endif
+#if !defined(SQLITE_OMIT_AUTOVACUUM)
+/* Opcode: IncrVacuum P1 P2 * * *
+**
+** Perform a single step of the incremental vacuum procedure on
+** the P1 database. If the vacuum has finished, jump to instruction
+** P2. Otherwise, fall through to the next instruction.
+*/
+case OP_IncrVacuum: {        /* jump */
+#if 0  /* local variables moved into u.ce */
+  Btree *pBt;
+#endif /* local variables moved into u.ce */
 
-#ifndef SQLITE_OMIT_TRIGGER
-  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
-  ** table. Don't do this if the table being ALTERed is itself located in
-  ** the temp database.
-  */
-  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
-    sqlite3NestedParse(pParse, 
-        "UPDATE sqlite_temp_master SET "
-            "sql = sqlite_rename_trigger(sql, %Q), "
-            "tbl_name = %Q "
-            "WHERE %s;", zName, zName, zWhere);
-    sqlite3_free(zWhere);
+  assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
+  u.ce.pBt = db->aDb[pOp->p1].pBt;
+  rc = sqlite3BtreeIncrVacuum(u.ce.pBt);
+  if( rc==SQLITE_DONE ){
+    pc = pOp->p2 - 1;
+    rc = SQLITE_OK;
   }
+  break;
+}
 #endif
 
-  /* Drop and reload the internal table schema. */
-  reloadTableSchema(pParse, pTab, zName);
-
-exit_rename_table:
-  sqlite3SrcListDelete(pSrc);
-  sqlite3_free(zName);
+/* Opcode: Expire P1 * * * *
+**
+** Cause precompiled statements to become expired. An expired statement
+** fails with an error code of SQLITE_SCHEMA if it is ever executed 
+** (via sqlite3_step()).
+** 
+** If P1 is 0, then all SQL statements become expired. If P1 is non-zero,
+** then only the currently executing statement is affected. 
+*/
+case OP_Expire: {
+  if( !pOp->p1 ){
+    sqlite3ExpirePreparedStatements(db);
+  }else{
+    p->expired = 1;
+  }
+  break;
 }
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
+/* Opcode: TableLock P1 P2 P3 P4 *
+**
+** Obtain a lock on a particular table. This instruction is only used when
+** the shared-cache feature is enabled. 
+**
+** P1 is the index of the database in sqlite3.aDb[] of the database
+** on which the lock is acquired.  A readlock is obtained if P3==0 or
+** a write lock if P3==1.
+**
+** P2 contains the root-page of the table to lock.
+**
+** P4 contains a pointer to the name of the table being locked. This is only
+** used to generate an error message if the lock cannot be obtained.
+*/
+case OP_TableLock: {
+  u8 isWriteLock = (u8)pOp->p3;
+  if( isWriteLock || 0==(db->flags&SQLITE_ReadUncommitted) ){
+    int p1 = pOp->p1; 
+    assert( p1>=0 && p1<db->nDb );
+    assert( (p->btreeMask & (1<<p1))!=0 );
+    assert( isWriteLock==0 || isWriteLock==1 );
+    rc = sqlite3BtreeLockTable(db->aDb[p1].pBt, pOp->p2, isWriteLock);
+    if( (rc&0xFF)==SQLITE_LOCKED ){
+      const char *z = pOp->p4.z;
+      sqlite3SetString(&p->zErrMsg, db, "database table is locked: %s", z);
+    }
+  }
+  break;
+}
+#endif /* SQLITE_OMIT_SHARED_CACHE */
 
-/*
-** This function is called after an "ALTER TABLE ... ADD" statement
-** has been parsed. Argument pColDef contains the text of the new
-** column definition.
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VBegin * * * P4 *
 **
-** The Table structure pParse->pNewTable was extended to include
-** the new column during parsing.
+** P4 may be a pointer to an sqlite3_vtab structure. If so, call the 
+** xBegin method for that table.
+**
+** Also, whether or not P4 is set, check that this is not being called from
+** within a callback to a virtual table xSync() method. If it is, the error
+** code will be set to SQLITE_LOCKED.
 */
-SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
-  Table *pNew;              /* Copy of pParse->pNewTable */
-  Table *pTab;              /* Table being altered */
-  int iDb;                  /* Database number */
-  const char *zDb;          /* Database name */
-  const char *zTab;         /* Table name */
-  char *zCol;               /* Null-terminated column definition */
-  Column *pCol;             /* The new column */
-  Expr *pDflt;              /* Default value for the new column */
-  sqlite3 *db;              /* The database connection; */
+case OP_VBegin: {
+#if 0  /* local variables moved into u.cf */
+  VTable *pVTab;
+#endif /* local variables moved into u.cf */
+  u.cf.pVTab = pOp->p4.pVtab;
+  rc = sqlite3VtabBegin(db, u.cf.pVTab);
+  if( u.cf.pVTab ){
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = u.cf.pVTab->pVtab->zErrMsg;
+    u.cf.pVTab->pVtab->zErrMsg = 0;
+  }
+  break;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-  if( pParse->nErr ) return;
-  pNew = pParse->pNewTable;
-  assert( pNew );
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VCreate P1 * * P4 *
+**
+** P4 is the name of a virtual table in database P1. Call the xCreate method
+** for that table.
+*/
+case OP_VCreate: {
+  rc = sqlite3VtabCallCreate(db, pOp->p1, pOp->p4.z, &p->zErrMsg);
+  break;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-  db = pParse->db;
-  assert( sqlite3BtreeHoldsAllMutexes(db) );
-  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
-  zDb = db->aDb[iDb].zName;
-  zTab = pNew->zName;
-  pCol = &pNew->aCol[pNew->nCol-1];
-  pDflt = pCol->pDflt;
-  pTab = sqlite3FindTable(db, zTab, zDb);
-  assert( pTab );
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VDestroy P1 * * P4 *
+**
+** P4 is the name of a virtual table in database P1.  Call the xDestroy method
+** of that table.
+*/
+case OP_VDestroy: {
+  p->inVtabMethod = 2;
+  rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p4.z);
+  p->inVtabMethod = 0;
+  break;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  /* Invoke the authorization callback. */
-  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
-    return;
-  }
-#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VOpen P1 * * P4 *
+**
+** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
+** P1 is a cursor number.  This opcode opens a cursor to the virtual
+** table and stores that cursor in P1.
+*/
+case OP_VOpen: {
+#if 0  /* local variables moved into u.cg */
+  VdbeCursor *pCur;
+  sqlite3_vtab_cursor *pVtabCursor;
+  sqlite3_vtab *pVtab;
+  sqlite3_module *pModule;
+#endif /* local variables moved into u.cg */
+
+  u.cg.pCur = 0;
+  u.cg.pVtabCursor = 0;
+  u.cg.pVtab = pOp->p4.pVtab->pVtab;
+  u.cg.pModule = (sqlite3_module *)u.cg.pVtab->pModule;
+  assert(u.cg.pVtab && u.cg.pModule);
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+  rc = u.cg.pModule->xOpen(u.cg.pVtab, &u.cg.pVtabCursor);
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = u.cg.pVtab->zErrMsg;
+  u.cg.pVtab->zErrMsg = 0;
+  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+  if( SQLITE_OK==rc ){
+    /* Initialize sqlite3_vtab_cursor base class */
+    u.cg.pVtabCursor->pVtab = u.cg.pVtab;
 
-  /* If the default value for the new column was specified with a 
-  ** literal NULL, then set pDflt to 0. This simplifies checking
-  ** for an SQL NULL default below.
-  */
-  if( pDflt && pDflt->op==TK_NULL ){
-    pDflt = 0;
+    /* Initialise vdbe cursor object */
+    u.cg.pCur = allocateCursor(p, pOp->p1, 0, -1, 0);
+    if( u.cg.pCur ){
+      u.cg.pCur->pVtabCursor = u.cg.pVtabCursor;
+      u.cg.pCur->pModule = u.cg.pVtabCursor->pVtab->pModule;
+    }else{
+      db->mallocFailed = 1;
+      u.cg.pModule->xClose(u.cg.pVtabCursor);
+    }
   }
+  break;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
-  ** If there is a NOT NULL constraint, then the default value for the
-  ** column must not be NULL.
-  */
-  if( pCol->isPrimKey ){
-    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
-    return;
-  }
-  if( pNew->pIndex ){
-    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
-    return;
-  }
-  if( pCol->notNull && !pDflt ){
-    sqlite3ErrorMsg(pParse, 
-        "Cannot add a NOT NULL column with default value NULL");
-    return;
-  }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VFilter P1 P2 P3 P4 *
+**
+** P1 is a cursor opened using VOpen.  P2 is an address to jump to if
+** the filtered result set is empty.
+**
+** P4 is either NULL or a string that was generated by the xBestIndex
+** method of the module.  The interpretation of the P4 string is left
+** to the module implementation.
+**
+** This opcode invokes the xFilter method on the virtual table specified
+** by P1.  The integer query plan parameter to xFilter is stored in register
+** P3. Register P3+1 stores the argc parameter to be passed to the
+** xFilter method. Registers P3+2..P3+1+argc are the argc
+** additional parameters which are passed to
+** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
+**
+** A jump is made to P2 if the result set after filtering would be empty.
+*/
+case OP_VFilter: {   /* jump */
+#if 0  /* local variables moved into u.ch */
+  int nArg;
+  int iQuery;
+  const sqlite3_module *pModule;
+  Mem *pQuery;
+  Mem *pArgc;
+  sqlite3_vtab_cursor *pVtabCursor;
+  sqlite3_vtab *pVtab;
+  VdbeCursor *pCur;
+  int res;
+  int i;
+  Mem **apArg;
+#endif /* local variables moved into u.ch */
+
+  u.ch.pQuery = &p->aMem[pOp->p3];
+  u.ch.pArgc = &u.ch.pQuery[1];
+  u.ch.pCur = p->apCsr[pOp->p1];
+  REGISTER_TRACE(pOp->p3, u.ch.pQuery);
+  assert( u.ch.pCur->pVtabCursor );
+  u.ch.pVtabCursor = u.ch.pCur->pVtabCursor;
+  u.ch.pVtab = u.ch.pVtabCursor->pVtab;
+  u.ch.pModule = u.ch.pVtab->pModule;
 
-  /* Ensure the default expression is something that sqlite3ValueFromExpr()
-  ** can handle (i.e. not CURRENT_TIME etc.)
-  */
-  if( pDflt ){
-    sqlite3_value *pVal;
-    if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
-      db->mallocFailed = 1;
-      return;
+  /* Grab the index number and argc parameters */
+  assert( (u.ch.pQuery->flags&MEM_Int)!=0 && u.ch.pArgc->flags==MEM_Int );
+  u.ch.nArg = (int)u.ch.pArgc->u.i;
+  u.ch.iQuery = (int)u.ch.pQuery->u.i;
+
+  /* Invoke the xFilter method */
+  {
+    u.ch.res = 0;
+    u.ch.apArg = p->apArg;
+    for(u.ch.i = 0; u.ch.i<u.ch.nArg; u.ch.i++){
+      u.ch.apArg[u.ch.i] = &u.ch.pArgc[u.ch.i+1];
+      storeTypeInfo(u.ch.apArg[u.ch.i], 0);
     }
-    if( !pVal ){
-      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
-      return;
+
+    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+    p->inVtabMethod = 1;
+    rc = u.ch.pModule->xFilter(u.ch.pVtabCursor, u.ch.iQuery, pOp->p4.z, u.ch.nArg, u.ch.apArg);
+    p->inVtabMethod = 0;
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = u.ch.pVtab->zErrMsg;
+    u.ch.pVtab->zErrMsg = 0;
+    if( rc==SQLITE_OK ){
+      u.ch.res = u.ch.pModule->xEof(u.ch.pVtabCursor);
     }
-    sqlite3ValueFree(pVal);
-  }
+    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
 
-  /* Modify the CREATE TABLE statement. */
-  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
-  if( zCol ){
-    char *zEnd = &zCol[pColDef->n-1];
-    while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
-      *zEnd-- = '\0';
+    if( u.ch.res ){
+      pc = pOp->p2 - 1;
     }
-    sqlite3NestedParse(pParse, 
-        "UPDATE \"%w\".%s SET "
-          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
-        "WHERE type = 'table' AND name = %Q", 
-      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
-      zTab
-    );
-    sqlite3_free(zCol);
   }
+  u.ch.pCur->nullRow = 0;
 
-  /* If the default value of the new column is NULL, then set the file
-  ** format to 2. If the default value of the new column is not NULL,
-  ** the file format becomes 3.
-  */
-  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
-
-  /* Reload the schema of the modified table. */
-  reloadTableSchema(pParse, pTab, pTab->zName);
+  break;
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/*
-** This function is called by the parser after the table-name in
-** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument 
-** pSrc is the full-name of the table being altered.
-**
-** This routine makes a (partial) copy of the Table structure
-** for the table being altered and sets Parse.pNewTable to point
-** to it. Routines called by the parser as the column definition
-** is parsed (i.e. sqlite3AddColumn()) add the new Column data to 
-** the copy. The copy of the Table structure is deleted by tokenize.c 
-** after parsing is finished.
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VColumn P1 P2 P3 * *
 **
-** Routine sqlite3AlterFinishAddColumn() will be called to complete
-** coding the "ALTER TABLE ... ADD" statement.
+** Store the value of the P2-th column of
+** the row of the virtual-table that the 
+** P1 cursor is pointing to into register P3.
 */
-SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
-  Table *pNew;
-  Table *pTab;
-  Vdbe *v;
-  int iDb;
-  int i;
-  int nAlloc;
-  sqlite3 *db = pParse->db;
-
-  /* Look up the table being altered. */
-  assert( pParse->pNewTable==0 );
-  assert( sqlite3BtreeHoldsAllMutexes(db) );
-  if( db->mallocFailed ) goto exit_begin_add_column;
-  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
-  if( !pTab ) goto exit_begin_add_column;
+case OP_VColumn: {
+#if 0  /* local variables moved into u.ci */
+  sqlite3_vtab *pVtab;
+  const sqlite3_module *pModule;
+  Mem *pDest;
+  sqlite3_context sContext;
+#endif /* local variables moved into u.ci */
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( IsVirtual(pTab) ){
-    sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
-    goto exit_begin_add_column;
+  VdbeCursor *pCur = p->apCsr[pOp->p1];
+  assert( pCur->pVtabCursor );
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  u.ci.pDest = &p->aMem[pOp->p3];
+  if( pCur->nullRow ){
+    sqlite3VdbeMemSetNull(u.ci.pDest);
+    break;
   }
-#endif
+  u.ci.pVtab = pCur->pVtabCursor->pVtab;
+  u.ci.pModule = u.ci.pVtab->pModule;
+  assert( u.ci.pModule->xColumn );
+  memset(&u.ci.sContext, 0, sizeof(u.ci.sContext));
 
-  /* Make sure this is not an attempt to ALTER a view. */
-  if( pTab->pSelect ){
-    sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
-    goto exit_begin_add_column;
-  }
+  /* The output cell may already have a buffer allocated. Move
+  ** the current contents to u.ci.sContext.s so in case the user-function
+  ** can use the already allocated buffer instead of allocating a
+  ** new one.
+  */
+  sqlite3VdbeMemMove(&u.ci.sContext.s, u.ci.pDest);
+  MemSetTypeFlag(&u.ci.sContext.s, MEM_Null);
 
-  assert( pTab->addColOffset>0 );
-  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+  rc = u.ci.pModule->xColumn(pCur->pVtabCursor, &u.ci.sContext, pOp->p2);
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = u.ci.pVtab->zErrMsg;
+  u.ci.pVtab->zErrMsg = 0;
+  if( u.ci.sContext.isError ){
+    rc = u.ci.sContext.isError;
+  }
 
-  /* Put a copy of the Table struct in Parse.pNewTable for the
-  ** sqlite3AddColumn() function and friends to modify.
+  /* Copy the result of the function to the P3 register. We
+  ** do this regardless of whether or not an error occurred to ensure any
+  ** dynamic allocation in u.ci.sContext.s (a Mem struct) is  released.
   */
-  pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
-  if( !pNew ) goto exit_begin_add_column;
-  pParse->pNewTable = pNew;
-  pNew->nRef = 1;
-  pNew->nCol = pTab->nCol;
-  assert( pNew->nCol>0 );
-  nAlloc = (((pNew->nCol-1)/8)*8)+8;
-  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
-  pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
-  pNew->zName = sqlite3DbStrDup(db, pTab->zName);
-  if( !pNew->aCol || !pNew->zName ){
-    db->mallocFailed = 1;
-    goto exit_begin_add_column;
+  sqlite3VdbeChangeEncoding(&u.ci.sContext.s, encoding);
+  REGISTER_TRACE(pOp->p3, u.ci.pDest);
+  sqlite3VdbeMemMove(u.ci.pDest, &u.ci.sContext.s);
+  UPDATE_MAX_BLOBSIZE(u.ci.pDest);
+
+  if( sqlite3SafetyOn(db) ){
+    goto abort_due_to_misuse;
   }
-  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
-  for(i=0; i<pNew->nCol; i++){
-    Column *pCol = &pNew->aCol[i];
-    pCol->zName = sqlite3DbStrDup(db, pCol->zName);
-    pCol->zColl = 0;
-    pCol->zType = 0;
-    pCol->pDflt = 0;
+  if( sqlite3VdbeMemTooBig(u.ci.pDest) ){
+    goto too_big;
   }
-  pNew->pSchema = db->aDb[iDb].pSchema;
-  pNew->addColOffset = pTab->addColOffset;
-  pNew->nRef = 1;
-
-  /* Begin a transaction and increment the schema cookie.  */
-  sqlite3BeginWriteOperation(pParse, 0, iDb);
-  v = sqlite3GetVdbe(pParse);
-  if( !v ) goto exit_begin_add_column;
-  sqlite3ChangeCookie(pParse, iDb);
-
-exit_begin_add_column:
-  sqlite3SrcListDelete(pSrc);
-  return;
+  break;
 }
-#endif  /* SQLITE_ALTER_TABLE */
-
-/************** End of alter.c ***********************************************/
-/************** Begin file analyze.c *****************************************/
-/*
-** 2005 July 8
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains code associated with the ANALYZE command.
-**
-** @(#) $Id: analyze.c,v 1.42 2008/03/25 09:47:35 danielk1977 Exp $
-*/
-#ifndef SQLITE_OMIT_ANALYZE
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/*
-** This routine generates code that opens the sqlite_stat1 table on cursor
-** iStatCur.
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VNext P1 P2 * * *
 **
-** If the sqlite_stat1 tables does not previously exist, it is created.
-** If it does previously exist, all entires associated with table zWhere
-** are removed.  If zWhere==0 then all entries are removed.
+** Advance virtual table P1 to the next row in its result set and
+** jump to instruction P2.  Or, if the virtual table has reached
+** the end of its result set, then fall through to the next instruction.
 */
-static void openStatTable(
-  Parse *pParse,          /* Parsing context */
-  int iDb,                /* The database we are looking in */
-  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
-  const char *zWhere      /* Delete entries associated with this table */
-){
-  sqlite3 *db = pParse->db;
-  Db *pDb;
-  int iRootPage;
-  int createStat1 = 0;
-  Table *pStat;
-  Vdbe *v = sqlite3GetVdbe(pParse);
+case OP_VNext: {   /* jump */
+#if 0  /* local variables moved into u.cj */
+  sqlite3_vtab *pVtab;
+  const sqlite3_module *pModule;
+  int res;
+  VdbeCursor *pCur;
+#endif /* local variables moved into u.cj */
 
-  if( v==0 ) return;
-  assert( sqlite3BtreeHoldsAllMutexes(db) );
-  assert( sqlite3VdbeDb(v)==db );
-  pDb = &db->aDb[iDb];
-  if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
-    /* The sqlite_stat1 tables does not exist.  Create it.  
-    ** Note that a side-effect of the CREATE TABLE statement is to leave
-    ** the rootpage of the new table in register pParse->regRoot.  This is
-    ** important because the OpenWrite opcode below will be needing it. */
-    sqlite3NestedParse(pParse,
-      "CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
-      pDb->zName
-    );
-    iRootPage = pParse->regRoot;
-    createStat1 = 1;  /* Cause rootpage to be taken from top of stack */
-  }else if( zWhere ){
-    /* The sqlite_stat1 table exists.  Delete all entries associated with
-    ** the table zWhere. */
-    sqlite3NestedParse(pParse,
-       "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
-       pDb->zName, zWhere
-    );
-    iRootPage = pStat->tnum;
-  }else{
-    /* The sqlite_stat1 table already exists.  Delete all rows. */
-    iRootPage = pStat->tnum;
-    sqlite3VdbeAddOp2(v, OP_Clear, pStat->tnum, iDb);
+  u.cj.res = 0;
+  u.cj.pCur = p->apCsr[pOp->p1];
+  assert( u.cj.pCur->pVtabCursor );
+  if( u.cj.pCur->nullRow ){
+    break;
   }
+  u.cj.pVtab = u.cj.pCur->pVtabCursor->pVtab;
+  u.cj.pModule = u.cj.pVtab->pModule;
+  assert( u.cj.pModule->xNext );
 
-  /* Open the sqlite_stat1 table for writing. Unless it was created
-  ** by this vdbe program, lock it for writing at the shared-cache level. 
-  ** If this vdbe did create the sqlite_stat1 table, then it must have 
-  ** already obtained a schema-lock, making the write-lock redundant.
+  /* Invoke the xNext() method of the module. There is no way for the
+  ** underlying implementation to return an error if one occurs during
+  ** xNext(). Instead, if an error occurs, true is returned (indicating that
+  ** data is available) and the error code returned when xColumn or
+  ** some other method is next invoked on the save virtual table cursor.
   */
-  if( !createStat1 ){
-    sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+  p->inVtabMethod = 1;
+  rc = u.cj.pModule->xNext(u.cj.pCur->pVtabCursor);
+  p->inVtabMethod = 0;
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = u.cj.pVtab->zErrMsg;
+  u.cj.pVtab->zErrMsg = 0;
+  if( rc==SQLITE_OK ){
+    u.cj.res = u.cj.pModule->xEof(u.cj.pCur->pVtabCursor);
+  }
+  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+
+  if( !u.cj.res ){
+    /* If there is data, jump to P2 */
+    pc = pOp->p2 - 1;
   }
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 3);
-  sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur, iRootPage, iDb);
-  sqlite3VdbeChangeP5(v, createStat1);
+  break;
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/*
-** Generate code to do an analysis of all indices associated with
-** a single table.
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VRename P1 * * P4 *
+**
+** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
+** This opcode invokes the corresponding xRename method. The value
+** in register P1 is passed as the zName argument to the xRename method.
 */
-static void analyzeOneTable(
-  Parse *pParse,   /* Parser context */
-  Table *pTab,     /* Table whose indices are to be analyzed */
-  int iStatCur,    /* Cursor that writes to the sqlite_stat1 table */
-  int iMem         /* Available memory locations begin here */
-){
-  Index *pIdx;     /* An index to being analyzed */
-  int iIdxCur;     /* Cursor number for index being analyzed */
-  int nCol;        /* Number of columns in the index */
-  Vdbe *v;         /* The virtual machine being built up */
-  int i;           /* Loop counter */
-  int topOfLoop;   /* The top of the loop */
-  int endOfLoop;   /* The end of the loop */
-  int addr;        /* The address of an instruction */
-  int iDb;         /* Index of database containing pTab */
+case OP_VRename: {
+#if 0  /* local variables moved into u.ck */
+  sqlite3_vtab *pVtab;
+  Mem *pName;
+#endif /* local variables moved into u.ck */
+
+  u.ck.pVtab = pOp->p4.pVtab->pVtab;
+  u.ck.pName = &p->aMem[pOp->p1];
+  assert( u.ck.pVtab->pModule->xRename );
+  REGISTER_TRACE(pOp->p1, u.ck.pName);
+  assert( u.ck.pName->flags & MEM_Str );
+  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+  rc = u.ck.pVtab->pModule->xRename(u.ck.pVtab, u.ck.pName->z);
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = u.ck.pVtab->zErrMsg;
+  u.ck.pVtab->zErrMsg = 0;
+  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
 
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 || pTab==0 || pTab->pIndex==0 ){
-    /* Do no analysis for tables that have no indices */
-    return;
-  }
-  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  assert( iDb>=0 );
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
-      pParse->db->aDb[iDb].zName ) ){
-    return;
-  }
+  break;
+}
 #endif
 
-  /* Establish a read-lock on the table at the shared-cache level. */
-  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
-
-  iIdxCur = pParse->nTab;
-  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
-    int regFields;    /* Register block for building records */
-    int regRec;       /* Register holding completed record */
-    int regTemp;      /* Temporary use register */
-    int regCol;       /* Content of a column from the table being analyzed */
-    int regRowid;     /* Rowid for the inserted record */
-    int regF2;
-
-    /* Open a cursor to the index to be analyzed
-    */
-    assert( iDb==sqlite3SchemaToIndex(pParse->db, pIdx->pSchema) );
-    nCol = pIdx->nColumn;
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nCol+1);
-    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
-        (char *)pKey, P4_KEYINFO_HANDOFF);
-    VdbeComment((v, "%s", pIdx->zName));
-    regFields = iMem+nCol*2;
-    regTemp = regRowid = regCol = regFields+3;
-    regRec = regCol+1;
-    if( regRec>pParse->nMem ){
-      pParse->nMem = regRec;
-    }
-
-    /* Memory cells are used as follows:
-    **
-    **    mem[iMem]:             The total number of rows in the table.
-    **    mem[iMem+1]:           Number of distinct values in column 1
-    **    ...
-    **    mem[iMem+nCol]:        Number of distinct values in column N
-    **    mem[iMem+nCol+1]       Last observed value of column 1
-    **    ...
-    **    mem[iMem+nCol+nCol]:   Last observed value of column N
-    **
-    ** Cells iMem through iMem+nCol are initialized to 0.  The others
-    ** are initialized to NULL.
-    */
-    for(i=0; i<=nCol; i++){
-      sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
-    }
-    for(i=0; i<nCol; i++){
-      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
-    }
-
-    /* Do the analysis.
-    */
-    endOfLoop = sqlite3VdbeMakeLabel(v);
-    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
-    topOfLoop = sqlite3VdbeCurrentAddr(v);
-    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
-    for(i=0; i<nCol; i++){
-      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
-      sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
-      /**** TODO:  add collating sequence *****/
-      sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
-    }
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
-    for(i=0; i<nCol; i++){
-      sqlite3VdbeJumpHere(v, topOfLoop + 2*(i + 1));
-      sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
-      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Opcode: VUpdate P1 P2 P3 P4 *
+**
+** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
+** This opcode invokes the corresponding xUpdate method. P2 values
+** are contiguous memory cells starting at P3 to pass to the xUpdate 
+** invocation. The value in register (P3+P2-1) corresponds to the 
+** p2th element of the argv array passed to xUpdate.
+**
+** The xUpdate method will do a DELETE or an INSERT or both.
+** The argv[0] element (which corresponds to memory cell P3)
+** is the rowid of a row to delete.  If argv[0] is NULL then no 
+** deletion occurs.  The argv[1] element is the rowid of the new 
+** row.  This can be NULL to have the virtual table select the new 
+** rowid for itself.  The subsequent elements in the array are 
+** the values of columns in the new row.
+**
+** If P2==1 then no insert is performed.  argv[0] is the rowid of
+** a row to delete.
+**
+** P1 is a boolean flag. If it is set to true and the xUpdate call
+** is successful, then the value returned by sqlite3_last_insert_rowid() 
+** is set to the value of the rowid for the row just inserted.
+*/
+case OP_VUpdate: {
+#if 0  /* local variables moved into u.cl */
+  sqlite3_vtab *pVtab;
+  sqlite3_module *pModule;
+  int nArg;
+  int i;
+  sqlite_int64 rowid;
+  Mem **apArg;
+  Mem *pX;
+#endif /* local variables moved into u.cl */
+
+  u.cl.pVtab = pOp->p4.pVtab->pVtab;
+  u.cl.pModule = (sqlite3_module *)u.cl.pVtab->pModule;
+  u.cl.nArg = pOp->p2;
+  assert( pOp->p4type==P4_VTAB );
+  if( ALWAYS(u.cl.pModule->xUpdate) ){
+    u.cl.apArg = p->apArg;
+    u.cl.pX = &p->aMem[pOp->p3];
+    for(u.cl.i=0; u.cl.i<u.cl.nArg; u.cl.i++){
+      storeTypeInfo(u.cl.pX, 0);
+      u.cl.apArg[u.cl.i] = u.cl.pX;
+      u.cl.pX++;
     }
-    sqlite3VdbeResolveLabel(v, endOfLoop);
-    sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
-    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
-
-    /* Store the results.  
-    **
-    ** The result is a single row of the sqlite_stat1 table.  The first
-    ** two columns are the names of the table and index.  The third column
-    ** is a string composed of a list of integer statistics about the
-    ** index.  The first integer in the list is the total number of entires
-    ** in the index.  There is one additional integer in the list for each
-    ** column of the table.  This additional integer is a guess of how many
-    ** rows of the table the index will select.  If D is the count of distinct
-    ** values and K is the total number of rows, then the integer is computed
-    ** as:
-    **
-    **        I = (K+D-1)/D
-    **
-    ** If K==0 then no entry is made into the sqlite_stat1 table.  
-    ** If K>0 then it is always the case the D>0 so division by zero
-    ** is never possible.
-    */
-    addr = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
-    sqlite3VdbeAddOp4(v, OP_String8, 0, regFields, 0, pTab->zName, 0);
-    sqlite3VdbeAddOp4(v, OP_String8, 0, regFields+1, 0, pIdx->zName, 0);
-    regF2 = regFields+2;
-    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regF2);
-    for(i=0; i<nCol; i++){
-      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
-      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regF2, regF2);
-      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
-      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
-      sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
-      sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
-      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regF2, regF2);
+    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
+    rc = u.cl.pModule->xUpdate(u.cl.pVtab, u.cl.nArg, u.cl.apArg, &u.cl.rowid);
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = u.cl.pVtab->zErrMsg;
+    u.cl.pVtab->zErrMsg = 0;
+    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
+    if( rc==SQLITE_OK && pOp->p1 ){
+      assert( u.cl.nArg>1 && u.cl.apArg[0] && (u.cl.apArg[0]->flags&MEM_Null) );
+      db->lastRowid = u.cl.rowid;
     }
-    sqlite3VdbeAddOp4(v, OP_MakeRecord, regFields, 3, regRec, "aaa", 0);
-    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
-    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
-    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
-    sqlite3VdbeJumpHere(v, addr);
+    p->nChange++;
   }
+  break;
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/*
-** Generate code that will cause the most recent index analysis to
-** be laoded into internal hash tables where is can be used.
+#ifndef  SQLITE_OMIT_PAGER_PRAGMAS
+/* Opcode: Pagecount P1 P2 * * *
+**
+** Write the current number of pages in database P1 to memory cell P2.
 */
-static void loadAnalysis(Parse *pParse, int iDb){
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3VdbeAddOp1(v, OP_LoadAnalysis, iDb);
+case OP_Pagecount: {            /* out2-prerelease */
+#if 0  /* local variables moved into u.cm */
+  int p1;
+  int nPage;
+  Pager *pPager;
+#endif /* local variables moved into u.cm */
+
+  u.cm.p1 = pOp->p1;
+  u.cm.pPager = sqlite3BtreePager(db->aDb[u.cm.p1].pBt);
+  rc = sqlite3PagerPagecount(u.cm.pPager, &u.cm.nPage);
+  /* OP_Pagecount is always called from within a read transaction.  The
+  ** page count has already been successfully read and cached.  So the
+  ** sqlite3PagerPagecount() call above cannot fail. */
+  if( ALWAYS(rc==SQLITE_OK) ){
+    pOut->flags = MEM_Int;
+    pOut->u.i = u.cm.nPage;
   }
+  break;
 }
+#endif
 
-/*
-** Generate code that will do an analysis of an entire database
+#ifndef SQLITE_OMIT_TRACE
+/* Opcode: Trace * * * P4 *
+**
+** If tracing is enabled (by the sqlite3_trace()) interface, then
+** the UTF-8 string contained in P4 is emitted on the trace callback.
 */
-static void analyzeDatabase(Parse *pParse, int iDb){
-  sqlite3 *db = pParse->db;
-  Schema *pSchema = db->aDb[iDb].pSchema;    /* Schema of database iDb */
-  HashElem *k;
-  int iStatCur;
-  int iMem;
+case OP_Trace: {
+#if 0  /* local variables moved into u.cn */
+  char *zTrace;
+#endif /* local variables moved into u.cn */
 
-  sqlite3BeginWriteOperation(pParse, 0, iDb);
-  iStatCur = pParse->nTab++;
-  openStatTable(pParse, iDb, iStatCur, 0);
-  iMem = pParse->nMem+1;
-  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
-    Table *pTab = (Table*)sqliteHashData(k);
-    analyzeOneTable(pParse, pTab, iStatCur, iMem);
+  u.cn.zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql);
+  if( u.cn.zTrace ){
+    if( db->xTrace ){
+      db->xTrace(db->pTraceArg, u.cn.zTrace);
+    }
+#ifdef SQLITE_DEBUG
+    if( (db->flags & SQLITE_SqlTrace)!=0 ){
+      sqlite3DebugPrintf("SQL-trace: %s\n", u.cn.zTrace);
+    }
+#endif /* SQLITE_DEBUG */
   }
-  loadAnalysis(pParse, iDb);
+  break;
 }
+#endif
 
+
+/* Opcode: Noop * * * * *
+**
+** Do nothing.  This instruction is often useful as a jump
+** destination.
+*/
 /*
-** Generate code that will do an analysis of a single table in
-** a database.
+** The magic Explain opcode are only inserted when explain==2 (which
+** is to say when the EXPLAIN QUERY PLAN syntax is used.)
+** This opcode records information from the optimizer.  It is the
+** the same as a no-op.  This opcodesnever appears in a real VM program.
 */
-static void analyzeTable(Parse *pParse, Table *pTab){
-  int iDb;
-  int iStatCur;
-
-  assert( pTab!=0 );
-  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  sqlite3BeginWriteOperation(pParse, 0, iDb);
-  iStatCur = pParse->nTab++;
-  openStatTable(pParse, iDb, iStatCur, pTab->zName);
-  analyzeOneTable(pParse, pTab, iStatCur, pParse->nMem+1);
-  loadAnalysis(pParse, iDb);
+default: {          /* This is really OP_Noop and OP_Explain */
+  break;
 }
 
-/*
-** Generate code for the ANALYZE command.  The parser calls this routine
-** when it recognizes an ANALYZE command.
-**
-**        ANALYZE                            -- 1
-**        ANALYZE  <database>                -- 2
-**        ANALYZE  ?<database>.?<tablename>  -- 3
-**
-** Form 1 causes all indices in all attached databases to be analyzed.
-** Form 2 analyzes all indices the single database named.
-** Form 3 analyzes all indices associated with the named table.
-*/
-SQLITE_PRIVATE void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
-  sqlite3 *db = pParse->db;
-  int iDb;
-  int i;
-  char *z, *zDb;
-  Table *pTab;
-  Token *pTableName;
+/*****************************************************************************
+** The cases of the switch statement above this line should all be indented
+** by 6 spaces.  But the left-most 6 spaces have been removed to improve the
+** readability.  From this point on down, the normal indentation rules are
+** restored.
+*****************************************************************************/
+    }
 
-  /* Read the database schema. If an error occurs, leave an error message
-  ** and code in pParse and return NULL. */
-  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-    return;
-  }
+#ifdef VDBE_PROFILE
+    {
+      u64 elapsed = sqlite3Hwtime() - start;
+      pOp->cycles += elapsed;
+      pOp->cnt++;
+#if 0
+        fprintf(stdout, "%10llu ", elapsed);
+        sqlite3VdbePrintOp(stdout, origPc, &p->aOp[origPc]);
+#endif
+    }
+#endif
 
-  if( pName1==0 ){
-    /* Form 1:  Analyze everything */
-    for(i=0; i<db->nDb; i++){
-      if( i==1 ) continue;  /* Do not analyze the TEMP database */
-      analyzeDatabase(pParse, i);
+    /* The following code adds nothing to the actual functionality
+    ** of the program.  It is only here for testing and debugging.
+    ** On the other hand, it does burn CPU cycles every time through
+    ** the evaluator loop.  So we can leave it out when NDEBUG is defined.
+    */
+#ifndef NDEBUG
+    assert( pc>=-1 && pc<p->nOp );
+
+#ifdef SQLITE_DEBUG
+    if( p->trace ){
+      if( rc!=0 ) fprintf(p->trace,"rc=%d\n",rc);
+      if( opProperty & OPFLG_OUT2_PRERELEASE ){
+        registerTrace(p->trace, pOp->p2, pOut);
+      }
+      if( opProperty & OPFLG_OUT3 ){
+        registerTrace(p->trace, pOp->p3, pOut);
+      }
     }
-  }else if( pName2==0 || pName2->n==0 ){
-    /* Form 2:  Analyze the database or table named */
-    iDb = sqlite3FindDb(db, pName1);
-    if( iDb>=0 ){
-      analyzeDatabase(pParse, iDb);
-    }else{
-      z = sqlite3NameFromToken(db, pName1);
-      if( z ){
-        pTab = sqlite3LocateTable(pParse, 0, z, 0);
-        sqlite3_free(z);
-        if( pTab ){
-          analyzeTable(pParse, pTab);
-        }
-      }
-    }
-  }else{
-    /* Form 3: Analyze the fully qualified table name */
-    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pTableName);
-    if( iDb>=0 ){
-      zDb = db->aDb[iDb].zName;
-      z = sqlite3NameFromToken(db, pTableName);
-      if( z ){
-        pTab = sqlite3LocateTable(pParse, 0, z, zDb);
-        sqlite3_free(z);
-        if( pTab ){
-          analyzeTable(pParse, pTab);
-        }
-      }
-    }   
+#endif  /* SQLITE_DEBUG */
+#endif  /* NDEBUG */
+  }  /* The end of the for(;;) loop the loops through opcodes */
+
+  /* If we reach this point, it means that execution is finished with
+  ** an error of some kind.
+  */
+vdbe_error_halt:
+  assert( rc );
+  p->rc = rc;
+  sqlite3VdbeHalt(p);
+  if( rc==SQLITE_IOERR_NOMEM ) db->mallocFailed = 1;
+  rc = SQLITE_ERROR;
+
+  /* This is the only way out of this procedure.  We have to
+  ** release the mutexes on btrees that were acquired at the
+  ** top. */
+vdbe_return:
+  sqlite3BtreeMutexArrayLeave(&p->aMutex);
+  return rc;
+
+  /* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
+  ** is encountered.
+  */
+too_big:
+  sqlite3SetString(&p->zErrMsg, db, "string or blob too big");
+  rc = SQLITE_TOOBIG;
+  goto vdbe_error_halt;
+
+  /* Jump to here if a malloc() fails.
+  */
+no_mem:
+  db->mallocFailed = 1;
+  sqlite3SetString(&p->zErrMsg, db, "out of memory");
+  rc = SQLITE_NOMEM;
+  goto vdbe_error_halt;
+
+  /* Jump to here for an SQLITE_MISUSE error.
+  */
+abort_due_to_misuse:
+  rc = SQLITE_MISUSE;
+  /* Fall thru into abort_due_to_error */
+
+  /* Jump to here for any other kind of fatal error.  The "rc" variable
+  ** should hold the error number.
+  */
+abort_due_to_error:
+  assert( p->zErrMsg==0 );
+  if( db->mallocFailed ) rc = SQLITE_NOMEM;
+  if( rc!=SQLITE_IOERR_NOMEM ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
   }
+  goto vdbe_error_halt;
+
+  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
+  ** flag.
+  */
+abort_due_to_interrupt:
+  assert( db->u1.isInterrupted );
+  rc = SQLITE_INTERRUPT;
+  p->rc = rc;
+  sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
+  goto vdbe_error_halt;
 }
 
+/************** End of vdbe.c ************************************************/
+/************** Begin file vdbeblob.c ****************************************/
 /*
-** Used to pass information from the analyzer reader through to the
-** callback routine.
+** 2007 May 1
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains code used to implement incremental BLOB I/O.
+**
+** $Id: vdbeblob.c,v 1.35 2009/07/02 07:47:33 danielk1977 Exp $
 */
-typedef struct analysisInfo analysisInfo;
-struct analysisInfo {
-  sqlite3 *db;
-  const char *zDatabase;
+
+
+#ifndef SQLITE_OMIT_INCRBLOB
+
+/*
+** Valid sqlite3_blob* handles point to Incrblob structures.
+*/
+typedef struct Incrblob Incrblob;
+struct Incrblob {
+  int flags;              /* Copy of "flags" passed to sqlite3_blob_open() */
+  int nByte;              /* Size of open blob, in bytes */
+  int iOffset;            /* Byte offset of blob in cursor data */
+  BtCursor *pCsr;         /* Cursor pointing at blob row */
+  sqlite3_stmt *pStmt;    /* Statement holding cursor open */
+  sqlite3 *db;            /* The associated database */
 };
 
 /*
-** This callback is invoked once for each index when reading the
-** sqlite_stat1 table.  
-**
-**     argv[0] = name of the index
-**     argv[1] = results of analysis - on integer for each column
+** Open a blob handle.
 */
-static int analysisLoader(void *pData, int argc, char **argv, char **azNotUsed){
-  analysisInfo *pInfo = (analysisInfo*)pData;
-  Index *pIndex;
-  int i, c;
-  unsigned int v;
-  const char *z;
+SQLITE_API int sqlite3_blob_open(
+  sqlite3* db,            /* The database connection */
+  const char *zDb,        /* The attached database containing the blob */
+  const char *zTable,     /* The table containing the blob */
+  const char *zColumn,    /* The column containing the blob */
+  sqlite_int64 iRow,      /* The row containing the glob */
+  int flags,              /* True -> read/write access, false -> read-only */
+  sqlite3_blob **ppBlob   /* Handle for accessing the blob returned here */
+){
+  int nAttempt = 0;
+  int iCol;               /* Index of zColumn in row-record */
 
-  assert( argc==2 );
-  if( argv==0 || argv[0]==0 || argv[1]==0 ){
-    return 0;
-  }
-  pIndex = sqlite3FindIndex(pInfo->db, argv[0], pInfo->zDatabase);
-  if( pIndex==0 ){
-    return 0;
+  /* This VDBE program seeks a btree cursor to the identified 
+  ** db/table/row entry. The reason for using a vdbe program instead
+  ** of writing code to use the b-tree layer directly is that the
+  ** vdbe program will take advantage of the various transaction,
+  ** locking and error handling infrastructure built into the vdbe.
+  **
+  ** After seeking the cursor, the vdbe executes an OP_ResultRow.
+  ** Code external to the Vdbe then "borrows" the b-tree cursor and
+  ** uses it to implement the blob_read(), blob_write() and 
+  ** blob_bytes() functions.
+  **
+  ** The sqlite3_blob_close() function finalizes the vdbe program,
+  ** which closes the b-tree cursor and (possibly) commits the 
+  ** transaction.
+  */
+  static const VdbeOpList openBlob[] = {
+    {OP_Transaction, 0, 0, 0},     /* 0: Start a transaction */
+    {OP_VerifyCookie, 0, 0, 0},    /* 1: Check the schema cookie */
+    {OP_TableLock, 0, 0, 0},       /* 2: Acquire a read or write lock */
+
+    /* One of the following two instructions is replaced by an OP_Noop. */
+    {OP_OpenRead, 0, 0, 0},        /* 3: Open cursor 0 for reading */
+    {OP_OpenWrite, 0, 0, 0},       /* 4: Open cursor 0 for read/write */
+
+    {OP_Variable, 1, 1, 1},        /* 5: Push the rowid to the stack */
+    {OP_NotExists, 0, 9, 1},       /* 6: Seek the cursor */
+    {OP_Column, 0, 0, 1},          /* 7  */
+    {OP_ResultRow, 1, 0, 0},       /* 8  */
+    {OP_Close, 0, 0, 0},           /* 9  */
+    {OP_Halt, 0, 0, 0},            /* 10 */
+  };
+
+  Vdbe *v = 0;
+  int rc = SQLITE_OK;
+  char *zErr = 0;
+  Table *pTab;
+  Parse *pParse;
+
+  *ppBlob = 0;
+  sqlite3_mutex_enter(db->mutex);
+  pParse = sqlite3StackAllocRaw(db, sizeof(*pParse));
+  if( pParse==0 ){
+    rc = SQLITE_NOMEM;
+    goto blob_open_out;
   }
-  z = argv[1];
-  for(i=0; *z && i<=pIndex->nColumn; i++){
-    v = 0;
-    while( (c=z[0])>='0' && c<='9' ){
-      v = v*10 + c - '0';
-      z++;
+  do {
+    memset(pParse, 0, sizeof(Parse));
+    pParse->db = db;
+
+    if( sqlite3SafetyOn(db) ){
+      sqlite3DbFree(db, zErr);
+      sqlite3StackFree(db, pParse);
+      sqlite3_mutex_leave(db->mutex);
+      return SQLITE_MISUSE;
     }
-    pIndex->aiRowEst[i] = v;
-    if( *z==' ' ) z++;
+
+    sqlite3BtreeEnterAll(db);
+    pTab = sqlite3LocateTable(pParse, 0, zTable, zDb);
+    if( pTab && IsVirtual(pTab) ){
+      pTab = 0;
+      sqlite3ErrorMsg(pParse, "cannot open virtual table: %s", zTable);
+    }
+#ifndef SQLITE_OMIT_VIEW
+    if( pTab && pTab->pSelect ){
+      pTab = 0;
+      sqlite3ErrorMsg(pParse, "cannot open view: %s", zTable);
+    }
+#endif
+    if( !pTab ){
+      if( pParse->zErrMsg ){
+        sqlite3DbFree(db, zErr);
+        zErr = pParse->zErrMsg;
+        pParse->zErrMsg = 0;
+      }
+      rc = SQLITE_ERROR;
+      (void)sqlite3SafetyOff(db);
+      sqlite3BtreeLeaveAll(db);
+      goto blob_open_out;
+    }
+
+    /* Now search pTab for the exact column. */
+    for(iCol=0; iCol < pTab->nCol; iCol++) {
+      if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
+        break;
+      }
+    }
+    if( iCol==pTab->nCol ){
+      sqlite3DbFree(db, zErr);
+      zErr = sqlite3MPrintf(db, "no such column: \"%s\"", zColumn);
+      rc = SQLITE_ERROR;
+      (void)sqlite3SafetyOff(db);
+      sqlite3BtreeLeaveAll(db);
+      goto blob_open_out;
+    }
+
+    /* If the value is being opened for writing, check that the
+    ** column is not indexed, and that it is not part of a foreign key. 
+    ** It is against the rules to open a column to which either of these
+    ** descriptions applies for writing.  */
+    if( flags ){
+      const char *zFault = 0;
+      Index *pIdx;
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+      if( db->flags&SQLITE_ForeignKeys ){
+        /* Check that the column is not part of an FK child key definition. It
+        ** is not necessary to check if it is part of a parent key, as parent
+        ** key columns must be indexed. The check below will pick up this 
+        ** case.  */
+        FKey *pFKey;
+        for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){
+          int j;
+          for(j=0; j<pFKey->nCol; j++){
+            if( pFKey->aCol[j].iFrom==iCol ){
+              zFault = "foreign key";
+            }
+          }
+        }
+      }
+#endif
+      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+        int j;
+        for(j=0; j<pIdx->nColumn; j++){
+          if( pIdx->aiColumn[j]==iCol ){
+            zFault = "indexed";
+          }
+        }
+      }
+      if( zFault ){
+        sqlite3DbFree(db, zErr);
+        zErr = sqlite3MPrintf(db, "cannot open %s column for writing", zFault);
+        rc = SQLITE_ERROR;
+        (void)sqlite3SafetyOff(db);
+        sqlite3BtreeLeaveAll(db);
+        goto blob_open_out;
+      }
+    }
+
+    v = sqlite3VdbeCreate(db);
+    if( v ){
+      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+      sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);
+      flags = !!flags;                 /* flags = (flags ? 1 : 0); */
+
+      /* Configure the OP_Transaction */
+      sqlite3VdbeChangeP1(v, 0, iDb);
+      sqlite3VdbeChangeP2(v, 0, flags);
+
+      /* Configure the OP_VerifyCookie */
+      sqlite3VdbeChangeP1(v, 1, iDb);
+      sqlite3VdbeChangeP2(v, 1, pTab->pSchema->schema_cookie);
+
+      /* Make sure a mutex is held on the table to be accessed */
+      sqlite3VdbeUsesBtree(v, iDb); 
+
+      /* Configure the OP_TableLock instruction */
+      sqlite3VdbeChangeP1(v, 2, iDb);
+      sqlite3VdbeChangeP2(v, 2, pTab->tnum);
+      sqlite3VdbeChangeP3(v, 2, flags);
+      sqlite3VdbeChangeP4(v, 2, pTab->zName, P4_TRANSIENT);
+
+      /* Remove either the OP_OpenWrite or OpenRead. Set the P2 
+      ** parameter of the other to pTab->tnum.  */
+      sqlite3VdbeChangeToNoop(v, 4 - flags, 1);
+      sqlite3VdbeChangeP2(v, 3 + flags, pTab->tnum);
+      sqlite3VdbeChangeP3(v, 3 + flags, iDb);
+
+      /* Configure the number of columns. Configure the cursor to
+      ** think that the table has one more column than it really
+      ** does. An OP_Column to retrieve this imaginary column will
+      ** always return an SQL NULL. This is useful because it means
+      ** we can invoke OP_Column to fill in the vdbe cursors type 
+      ** and offset cache without causing any IO.
+      */
+      sqlite3VdbeChangeP4(v, 3+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
+      sqlite3VdbeChangeP2(v, 7, pTab->nCol);
+      if( !db->mallocFailed ){
+        sqlite3VdbeMakeReady(v, 1, 1, 1, 0, 0, 0);
+      }
+    }
+   
+    sqlite3BtreeLeaveAll(db);
+    rc = sqlite3SafetyOff(db);
+    if( NEVER(rc!=SQLITE_OK) || db->mallocFailed ){
+      goto blob_open_out;
+    }
+
+    sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
+    rc = sqlite3_step((sqlite3_stmt *)v);
+    if( rc!=SQLITE_ROW ){
+      nAttempt++;
+      rc = sqlite3_finalize((sqlite3_stmt *)v);
+      sqlite3DbFree(db, zErr);
+      zErr = sqlite3MPrintf(db, sqlite3_errmsg(db));
+      v = 0;
+    }
+  } while( nAttempt<5 && rc==SQLITE_SCHEMA );
+
+  if( rc==SQLITE_ROW ){
+    /* The row-record has been opened successfully. Check that the
+    ** column in question contains text or a blob. If it contains
+    ** text, it is up to the caller to get the encoding right.
+    */
+    Incrblob *pBlob;
+    u32 type = v->apCsr[0]->aType[iCol];
+
+    if( type<12 ){
+      sqlite3DbFree(db, zErr);
+      zErr = sqlite3MPrintf(db, "cannot open value of type %s",
+          type==0?"null": type==7?"real": "integer"
+      );
+      rc = SQLITE_ERROR;
+      goto blob_open_out;
+    }
+    pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
+    if( db->mallocFailed ){
+      sqlite3DbFree(db, pBlob);
+      goto blob_open_out;
+    }
+    pBlob->flags = flags;
+    pBlob->pCsr =  v->apCsr[0]->pCursor;
+    sqlite3BtreeEnterCursor(pBlob->pCsr);
+    sqlite3BtreeCacheOverflow(pBlob->pCsr);
+    sqlite3BtreeLeaveCursor(pBlob->pCsr);
+    pBlob->pStmt = (sqlite3_stmt *)v;
+    pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
+    pBlob->nByte = sqlite3VdbeSerialTypeLen(type);
+    pBlob->db = db;
+    *ppBlob = (sqlite3_blob *)pBlob;
+    rc = SQLITE_OK;
+  }else if( rc==SQLITE_OK ){
+    sqlite3DbFree(db, zErr);
+    zErr = sqlite3MPrintf(db, "no such rowid: %lld", iRow);
+    rc = SQLITE_ERROR;
   }
-  return 0;
+
+blob_open_out:
+  if( v && (rc!=SQLITE_OK || db->mallocFailed) ){
+    sqlite3VdbeFinalize(v);
+  }
+  sqlite3Error(db, rc, zErr);
+  sqlite3DbFree(db, zErr);
+  sqlite3StackFree(db, pParse);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 
 /*
-** Load the content of the sqlite_stat1 table into the index hash tables.
+** Close a blob handle that was previously created using
+** sqlite3_blob_open().
 */
-SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
-  analysisInfo sInfo;
-  HashElem *i;
-  char *zSql;
+SQLITE_API int sqlite3_blob_close(sqlite3_blob *pBlob){
+  Incrblob *p = (Incrblob *)pBlob;
   int rc;
+  sqlite3 *db;
 
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( db->aDb[iDb].pBt!=0 );
-  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
-
-  /* Clear any prior statistics */
-  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
-    Index *pIdx = sqliteHashData(i);
-    sqlite3DefaultRowEst(pIdx);
+  if( p ){
+    db = p->db;
+    sqlite3_mutex_enter(db->mutex);
+    rc = sqlite3_finalize(p->pStmt);
+    sqlite3DbFree(db, p);
+    sqlite3_mutex_leave(db->mutex);
+  }else{
+    rc = SQLITE_OK;
   }
+  return rc;
+}
 
-  /* Check to make sure the sqlite_stat1 table existss */
-  sInfo.db = db;
-  sInfo.zDatabase = db->aDb[iDb].zName;
-  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
-     return SQLITE_ERROR;
-  }
+/*
+** Perform a read or write operation on a blob
+*/
+static int blobReadWrite(
+  sqlite3_blob *pBlob, 
+  void *z, 
+  int n, 
+  int iOffset, 
+  int (*xCall)(BtCursor*, u32, u32, void*)
+){
+  int rc;
+  Incrblob *p = (Incrblob *)pBlob;
+  Vdbe *v;
+  sqlite3 *db;
 
+  if( p==0 ) return SQLITE_MISUSE;
+  db = p->db;
+  sqlite3_mutex_enter(db->mutex);
+  v = (Vdbe*)p->pStmt;
 
-  /* Load new statistics out of the sqlite_stat1 table */
-  zSql = sqlite3MPrintf(db, "SELECT idx, stat FROM %Q.sqlite_stat1",
-                        sInfo.zDatabase);
-  (void)sqlite3SafetyOff(db);
-  rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
-  (void)sqlite3SafetyOn(db);
-  sqlite3_free(zSql);
+  if( n<0 || iOffset<0 || (iOffset+n)>p->nByte ){
+    /* Request is out of range. Return a transient error. */
+    rc = SQLITE_ERROR;
+    sqlite3Error(db, SQLITE_ERROR, 0);
+  } else if( v==0 ){
+    /* If there is no statement handle, then the blob-handle has
+    ** already been invalidated. Return SQLITE_ABORT in this case.
+    */
+    rc = SQLITE_ABORT;
+  }else{
+    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
+    ** returned, clean-up the statement handle.
+    */
+    assert( db == v->db );
+    sqlite3BtreeEnterCursor(p->pCsr);
+    rc = xCall(p->pCsr, iOffset+p->iOffset, n, z);
+    sqlite3BtreeLeaveCursor(p->pCsr);
+    if( rc==SQLITE_ABORT ){
+      sqlite3VdbeFinalize(v);
+      p->pStmt = 0;
+    }else{
+      db->errCode = rc;
+      v->rc = rc;
+    }
+  }
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
   return rc;
 }
 
+/*
+** Read data from a blob handle.
+*/
+SQLITE_API int sqlite3_blob_read(sqlite3_blob *pBlob, void *z, int n, int iOffset){
+  return blobReadWrite(pBlob, z, n, iOffset, sqlite3BtreeData);
+}
 
-#endif /* SQLITE_OMIT_ANALYZE */
+/*
+** Write data to a blob handle.
+*/
+SQLITE_API int sqlite3_blob_write(sqlite3_blob *pBlob, const void *z, int n, int iOffset){
+  return blobReadWrite(pBlob, (void *)z, n, iOffset, sqlite3BtreePutData);
+}
 
-/************** End of analyze.c *********************************************/
-/************** Begin file attach.c ******************************************/
 /*
-** 2003 April 6
+** Query a blob handle for the size of the data.
+**
+** The Incrblob.nByte field is fixed for the lifetime of the Incrblob
+** so no mutex is required for access.
+*/
+SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *pBlob){
+  Incrblob *p = (Incrblob *)pBlob;
+  return p ? p->nByte : 0;
+}
+
+#endif /* #ifndef SQLITE_OMIT_INCRBLOB */
+
+/************** End of vdbeblob.c ********************************************/
+/************** Begin file journal.c *****************************************/
+/*
+** 2007 August 22
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -52084,765 +58154,638 @@ SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains code used to implement the ATTACH and DETACH commands.
 **
-** $Id: attach.c,v 1.75 2008/04/17 17:02:01 drh Exp $
+** @(#) $Id: journal.c,v 1.9 2009/01/20 17:06:27 danielk1977 Exp $
 */
 
-#ifndef SQLITE_OMIT_ATTACH
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+
 /*
-** Resolve an expression that was part of an ATTACH or DETACH statement. This
-** is slightly different from resolving a normal SQL expression, because simple
-** identifiers are treated as strings, not possible column names or aliases.
-**
-** i.e. if the parser sees:
-**
-**     ATTACH DATABASE abc AS def
-**
-** it treats the two expressions as literal strings 'abc' and 'def' instead of
-** looking for columns of the same name.
-**
-** This only applies to the root node of pExpr, so the statement:
+** This file implements a special kind of sqlite3_file object used
+** by SQLite to create journal files if the atomic-write optimization
+** is enabled.
 **
-**     ATTACH DATABASE abc||def AS 'db2'
+** The distinctive characteristic of this sqlite3_file is that the
+** actual on disk file is created lazily. When the file is created,
+** the caller specifies a buffer size for an in-memory buffer to
+** be used to service read() and write() requests. The actual file
+** on disk is not created or populated until either:
 **
-** will fail because neither abc or def can be resolved.
+**   1) The in-memory representation grows too large for the allocated 
+**      buffer, or
+**   2) The sqlite3JournalCreate() function is called.
 */
-static int resolveAttachExpr(NameContext *pName, Expr *pExpr)
-{
+
+
+
+/*
+** A JournalFile object is a subclass of sqlite3_file used by
+** as an open file handle for journal files.
+*/
+struct JournalFile {
+  sqlite3_io_methods *pMethod;    /* I/O methods on journal files */
+  int nBuf;                       /* Size of zBuf[] in bytes */
+  char *zBuf;                     /* Space to buffer journal writes */
+  int iSize;                      /* Amount of zBuf[] currently used */
+  int flags;                      /* xOpen flags */
+  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
+  sqlite3_file *pReal;            /* The "real" underlying file descriptor */
+  const char *zJournal;           /* Name of the journal file */
+};
+typedef struct JournalFile JournalFile;
+
+/*
+** If it does not already exists, create and populate the on-disk file 
+** for JournalFile p.
+*/
+static int createFile(JournalFile *p){
   int rc = SQLITE_OK;
-  if( pExpr ){
-    if( pExpr->op!=TK_ID ){
-      rc = sqlite3ExprResolveNames(pName, pExpr);
-      if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){
-        sqlite3ErrorMsg(pName->pParse, "invalid name: \"%T\"", &pExpr->span);
-        return SQLITE_ERROR;
+  if( !p->pReal ){
+    sqlite3_file *pReal = (sqlite3_file *)&p[1];
+    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
+    if( rc==SQLITE_OK ){
+      p->pReal = pReal;
+      if( p->iSize>0 ){
+        assert(p->iSize<=p->nBuf);
+        rc = sqlite3OsWrite(p->pReal, p->zBuf, p->iSize, 0);
       }
-    }else{
-      pExpr->op = TK_STRING;
     }
   }
   return rc;
 }
 
 /*
-** An SQL user-function registered to do the work of an ATTACH statement. The
-** three arguments to the function come directly from an attach statement:
-**
-**     ATTACH DATABASE x AS y KEY z
-**
-**     SELECT sqlite_attach(x, y, z)
-**
-** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
-** third argument.
+** Close the file.
 */
-static void attachFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  int i;
-  int rc = 0;
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  const char *zName;
-  const char *zFile;
-  Db *aNew;
-  char *zErrDyn = 0;
-  char zErr[128];
-
-  zFile = (const char *)sqlite3_value_text(argv[0]);
-  zName = (const char *)sqlite3_value_text(argv[1]);
-  if( zFile==0 ) zFile = "";
-  if( zName==0 ) zName = "";
-
-  /* Check for the following errors:
-  **
-  **     * Too many attached databases,
-  **     * Transaction currently open
-  **     * Specified database name already being used.
-  */
-  if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){
-    sqlite3_snprintf(
-      sizeof(zErr), zErr, "too many attached databases - max %d", 
-      db->aLimit[SQLITE_LIMIT_ATTACHED]
-    );
-    goto attach_error;
-  }
-  if( !db->autoCommit ){
-    sqlite3_snprintf(sizeof(zErr), zErr,
-                     "cannot ATTACH database within transaction");
-    goto attach_error;
-  }
-  for(i=0; i<db->nDb; i++){
-    char *z = db->aDb[i].zName;
-    if( z && zName && sqlite3StrICmp(z, zName)==0 ){
-      sqlite3_snprintf(sizeof(zErr), zErr, 
-                       "database %s is already in use", zName);
-      goto attach_error;
-    }
+static int jrnlClose(sqlite3_file *pJfd){
+  JournalFile *p = (JournalFile *)pJfd;
+  if( p->pReal ){
+    sqlite3OsClose(p->pReal);
   }
+  sqlite3_free(p->zBuf);
+  return SQLITE_OK;
+}
 
-  /* Allocate the new entry in the db->aDb[] array and initialise the schema
-  ** hash tables.
-  */
-  if( db->aDb==db->aDbStatic ){
-    aNew = sqlite3_malloc( sizeof(db->aDb[0])*3 );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      return;
-    }
-    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
+/*
+** Read data from the file.
+*/
+static int jrnlRead(
+  sqlite3_file *pJfd,    /* The journal file from which to read */
+  void *zBuf,            /* Put the results here */
+  int iAmt,              /* Number of bytes to read */
+  sqlite_int64 iOfst     /* Begin reading at this offset */
+){
+  int rc = SQLITE_OK;
+  JournalFile *p = (JournalFile *)pJfd;
+  if( p->pReal ){
+    rc = sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst);
+  }else if( (iAmt+iOfst)>p->iSize ){
+    rc = SQLITE_IOERR_SHORT_READ;
   }else{
-    aNew = sqlite3_realloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      return;
-    } 
+    memcpy(zBuf, &p->zBuf[iOfst], iAmt);
   }
-  db->aDb = aNew;
-  aNew = &db->aDb[db->nDb++];
-  memset(aNew, 0, sizeof(*aNew));
+  return rc;
+}
 
-  /* Open the database file. If the btree is successfully opened, use
-  ** it to obtain the database schema. At this point the schema may
-  ** or may not be initialised.
-  */
-  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE,
-                           db->openFlags | SQLITE_OPEN_MAIN_DB,
-                           &aNew->pBt);
+/*
+** Write data to the file.
+*/
+static int jrnlWrite(
+  sqlite3_file *pJfd,    /* The journal file into which to write */
+  const void *zBuf,      /* Take data to be written from here */
+  int iAmt,              /* Number of bytes to write */
+  sqlite_int64 iOfst     /* Begin writing at this offset into the file */
+){
+  int rc = SQLITE_OK;
+  JournalFile *p = (JournalFile *)pJfd;
+  if( !p->pReal && (iOfst+iAmt)>p->nBuf ){
+    rc = createFile(p);
+  }
   if( rc==SQLITE_OK ){
-    Pager *pPager;
-    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
-    if( !aNew->pSchema ){
-      rc = SQLITE_NOMEM;
-    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
-      sqlite3_snprintf(sizeof(zErr), zErr, 
-        "attached databases must use the same text encoding as main database");
-      goto attach_error;
+    if( p->pReal ){
+      rc = sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
+    }else{
+      memcpy(&p->zBuf[iOfst], zBuf, iAmt);
+      if( p->iSize<(iOfst+iAmt) ){
+        p->iSize = (iOfst+iAmt);
+      }
     }
-    pPager = sqlite3BtreePager(aNew->pBt);
-    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
-    sqlite3PagerJournalMode(pPager, db->dfltJournalMode);
   }
-  aNew->zName = sqlite3DbStrDup(db, zName);
-  aNew->safety_level = 3;
+  return rc;
+}
 
-#if SQLITE_HAS_CODEC
-  {
-    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
-    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
-    int nKey;
-    char *zKey;
-    int t = sqlite3_value_type(argv[2]);
-    switch( t ){
-      case SQLITE_INTEGER:
-      case SQLITE_FLOAT:
-        zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
-        rc = SQLITE_ERROR;
-        break;
-        
-      case SQLITE_TEXT:
-      case SQLITE_BLOB:
-        nKey = sqlite3_value_bytes(argv[2]);
-        zKey = (char *)sqlite3_value_blob(argv[2]);
-        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
-        break;
+/*
+** Truncate the file.
+*/
+static int jrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
+  int rc = SQLITE_OK;
+  JournalFile *p = (JournalFile *)pJfd;
+  if( p->pReal ){
+    rc = sqlite3OsTruncate(p->pReal, size);
+  }else if( size<p->iSize ){
+    p->iSize = size;
+  }
+  return rc;
+}
 
-      case SQLITE_NULL:
-        /* No key specified.  Use the key from the main database */
-        sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
-        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
-        break;
-    }
+/*
+** Sync the file.
+*/
+static int jrnlSync(sqlite3_file *pJfd, int flags){
+  int rc;
+  JournalFile *p = (JournalFile *)pJfd;
+  if( p->pReal ){
+    rc = sqlite3OsSync(p->pReal, flags);
+  }else{
+    rc = SQLITE_OK;
   }
-#endif
+  return rc;
+}
 
-  /* If the file was opened successfully, read the schema for the new database.
-  ** If this fails, or if opening the file failed, then close the file and 
-  ** remove the entry from the db->aDb[] array. i.e. put everything back the way
-  ** we found it.
-  */
-  if( rc==SQLITE_OK ){
-    (void)sqlite3SafetyOn(db);
-    sqlite3BtreeEnterAll(db);
-    rc = sqlite3Init(db, &zErrDyn);
-    sqlite3BtreeLeaveAll(db);
-    (void)sqlite3SafetyOff(db);
+/*
+** Query the size of the file in bytes.
+*/
+static int jrnlFileSize(sqlite3_file *pJfd, sqlite_int64 *pSize){
+  int rc = SQLITE_OK;
+  JournalFile *p = (JournalFile *)pJfd;
+  if( p->pReal ){
+    rc = sqlite3OsFileSize(p->pReal, pSize);
+  }else{
+    *pSize = (sqlite_int64) p->iSize;
   }
-  if( rc ){
-    int iDb = db->nDb - 1;
-    assert( iDb>=2 );
-    if( db->aDb[iDb].pBt ){
-      sqlite3BtreeClose(db->aDb[iDb].pBt);
-      db->aDb[iDb].pBt = 0;
-      db->aDb[iDb].pSchema = 0;
-    }
-    sqlite3ResetInternalSchema(db, 0);
-    db->nDb = iDb;
-    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
-      db->mallocFailed = 1;
-      sqlite3_snprintf(sizeof(zErr),zErr, "out of memory");
-    }else{
-      sqlite3_snprintf(sizeof(zErr),zErr, "unable to open database: %s", zFile);
+  return rc;
+}
+
+/*
+** Table of methods for JournalFile sqlite3_file object.
+*/
+static struct sqlite3_io_methods JournalFileMethods = {
+  1,             /* iVersion */
+  jrnlClose,     /* xClose */
+  jrnlRead,      /* xRead */
+  jrnlWrite,     /* xWrite */
+  jrnlTruncate,  /* xTruncate */
+  jrnlSync,      /* xSync */
+  jrnlFileSize,  /* xFileSize */
+  0,             /* xLock */
+  0,             /* xUnlock */
+  0,             /* xCheckReservedLock */
+  0,             /* xFileControl */
+  0,             /* xSectorSize */
+  0              /* xDeviceCharacteristics */
+};
+
+/* 
+** Open a journal file.
+*/
+SQLITE_PRIVATE int sqlite3JournalOpen(
+  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
+  const char *zName,         /* Name of the journal file */
+  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
+  int flags,                 /* Opening flags */
+  int nBuf                   /* Bytes buffered before opening the file */
+){
+  JournalFile *p = (JournalFile *)pJfd;
+  memset(p, 0, sqlite3JournalSize(pVfs));
+  if( nBuf>0 ){
+    p->zBuf = sqlite3MallocZero(nBuf);
+    if( !p->zBuf ){
+      return SQLITE_NOMEM;
     }
-    goto attach_error;
+  }else{
+    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
   }
-  
-  return;
+  p->pMethod = &JournalFileMethods;
+  p->nBuf = nBuf;
+  p->flags = flags;
+  p->zJournal = zName;
+  p->pVfs = pVfs;
+  return SQLITE_OK;
+}
 
-attach_error:
-  /* Return an error if we get here */
-  if( zErrDyn ){
-    sqlite3_result_error(context, zErrDyn, -1);
-    sqlite3_free(zErrDyn);
-  }else{
-    zErr[sizeof(zErr)-1] = 0;
-    sqlite3_result_error(context, zErr, -1);
+/*
+** If the argument p points to a JournalFile structure, and the underlying
+** file has not yet been created, create it now.
+*/
+SQLITE_PRIVATE int sqlite3JournalCreate(sqlite3_file *p){
+  if( p->pMethods!=&JournalFileMethods ){
+    return SQLITE_OK;
   }
-  if( rc ) sqlite3_result_error_code(context, rc);
+  return createFile((JournalFile *)p);
+}
+
+/* 
+** Return the number of bytes required to store a JournalFile that uses vfs
+** pVfs to create the underlying on-disk files.
+*/
+SQLITE_PRIVATE int sqlite3JournalSize(sqlite3_vfs *pVfs){
+  return (pVfs->szOsFile+sizeof(JournalFile));
 }
+#endif
 
+/************** End of journal.c *********************************************/
+/************** Begin file memjournal.c **************************************/
 /*
-** An SQL user-function registered to do the work of an DETACH statement. The
-** three arguments to the function come directly from a detach statement:
+** 2008 October 7
 **
-**     DETACH DATABASE x
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-**     SELECT sqlite_detach(x)
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains code use to implement an in-memory rollback journal.
+** The in-memory rollback journal is used to journal transactions for
+** ":memory:" databases and when the journal_mode=MEMORY pragma is used.
+**
+** @(#) $Id: memjournal.c,v 1.12 2009/05/04 11:42:30 danielk1977 Exp $
 */
-static void detachFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  const char *zName = (const char *)sqlite3_value_text(argv[0]);
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  int i;
-  Db *pDb = 0;
-  char zErr[128];
 
-  if( zName==0 ) zName = "";
-  for(i=0; i<db->nDb; i++){
-    pDb = &db->aDb[i];
-    if( pDb->pBt==0 ) continue;
-    if( sqlite3StrICmp(pDb->zName, zName)==0 ) break;
-  }
+/* Forward references to internal structures */
+typedef struct MemJournal MemJournal;
+typedef struct FilePoint FilePoint;
+typedef struct FileChunk FileChunk;
 
-  if( i>=db->nDb ){
-    sqlite3_snprintf(sizeof(zErr),zErr, "no such database: %s", zName);
-    goto detach_error;
-  }
-  if( i<2 ){
-    sqlite3_snprintf(sizeof(zErr),zErr, "cannot detach database %s", zName);
-    goto detach_error;
-  }
-  if( !db->autoCommit ){
-    sqlite3_snprintf(sizeof(zErr), zErr,
-                     "cannot DETACH database within transaction");
-    goto detach_error;
-  }
-  if( sqlite3BtreeIsInReadTrans(pDb->pBt) ){
-    sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
-    goto detach_error;
-  }
+/* Space to hold the rollback journal is allocated in increments of
+** this many bytes.
+**
+** The size chosen is a little less than a power of two.  That way,
+** the FileChunk object will have a size that almost exactly fills
+** a power-of-two allocation.  This mimimizes wasted space in power-of-two
+** memory allocators.
+*/
+#define JOURNAL_CHUNKSIZE ((int)(1024-sizeof(FileChunk*)))
 
-  sqlite3BtreeClose(pDb->pBt);
-  pDb->pBt = 0;
-  pDb->pSchema = 0;
-  sqlite3ResetInternalSchema(db, 0);
-  return;
+/* Macro to find the minimum of two numeric values.
+*/
+#ifndef MIN
+# define MIN(x,y) ((x)<(y)?(x):(y))
+#endif
 
-detach_error:
-  sqlite3_result_error(context, zErr, -1);
-}
+/*
+** The rollback journal is composed of a linked list of these structures.
+*/
+struct FileChunk {
+  FileChunk *pNext;               /* Next chunk in the journal */
+  u8 zChunk[JOURNAL_CHUNKSIZE];   /* Content of this chunk */
+};
 
 /*
-** This procedure generates VDBE code for a single invocation of either the
-** sqlite_detach() or sqlite_attach() SQL user functions.
+** An instance of this object serves as a cursor into the rollback journal.
+** The cursor can be either for reading or writing.
 */
-static void codeAttach(
-  Parse *pParse,       /* The parser context */
-  int type,            /* Either SQLITE_ATTACH or SQLITE_DETACH */
-  const char *zFunc,   /* Either "sqlite_attach" or "sqlite_detach */
-  int nFunc,           /* Number of args to pass to zFunc */
-  Expr *pAuthArg,      /* Expression to pass to authorization callback */
-  Expr *pFilename,     /* Name of database file */
-  Expr *pDbname,       /* Name of the database to use internally */
-  Expr *pKey           /* Database key for encryption extension */
-){
-  int rc;
-  NameContext sName;
-  Vdbe *v;
-  FuncDef *pFunc;
-  sqlite3* db = pParse->db;
-  int regArgs;
+struct FilePoint {
+  sqlite3_int64 iOffset;          /* Offset from the beginning of the file */
+  FileChunk *pChunk;              /* Specific chunk into which cursor points */
+};
 
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  assert( db->mallocFailed || pAuthArg );
-  if( pAuthArg ){
-    char *zAuthArg = sqlite3NameFromToken(db, &pAuthArg->span);
-    if( !zAuthArg ){
-      goto attach_end;
-    }
-    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
-    sqlite3_free(zAuthArg);
-    if(rc!=SQLITE_OK ){
-      goto attach_end;
+/*
+** This subclass is a subclass of sqlite3_file.  Each open memory-journal
+** is an instance of this class.
+*/
+struct MemJournal {
+  sqlite3_io_methods *pMethod;    /* Parent class. MUST BE FIRST */
+  FileChunk *pFirst;              /* Head of in-memory chunk-list */
+  FilePoint endpoint;             /* Pointer to the end of the file */
+  FilePoint readpoint;            /* Pointer to the end of the last xRead() */
+};
+
+/*
+** Read data from the in-memory journal file.  This is the implementation
+** of the sqlite3_vfs.xRead method.
+*/
+static int memjrnlRead(
+  sqlite3_file *pJfd,    /* The journal file from which to read */
+  void *zBuf,            /* Put the results here */
+  int iAmt,              /* Number of bytes to read */
+  sqlite_int64 iOfst     /* Begin reading at this offset */
+){
+  MemJournal *p = (MemJournal *)pJfd;
+  u8 *zOut = zBuf;
+  int nRead = iAmt;
+  int iChunkOffset;
+  FileChunk *pChunk;
+
+  /* SQLite never tries to read past the end of a rollback journal file */
+  assert( iOfst+iAmt<=p->endpoint.iOffset );
+
+  if( p->readpoint.iOffset!=iOfst || iOfst==0 ){
+    sqlite3_int64 iOff = 0;
+    for(pChunk=p->pFirst; 
+        ALWAYS(pChunk) && (iOff+JOURNAL_CHUNKSIZE)<=iOfst;
+        pChunk=pChunk->pNext
+    ){
+      iOff += JOURNAL_CHUNKSIZE;
     }
+  }else{
+    pChunk = p->readpoint.pChunk;
   }
-#endif /* SQLITE_OMIT_AUTHORIZATION */
 
-  memset(&sName, 0, sizeof(NameContext));
-  sName.pParse = pParse;
+  iChunkOffset = (int)(iOfst%JOURNAL_CHUNKSIZE);
+  do {
+    int iSpace = JOURNAL_CHUNKSIZE - iChunkOffset;
+    int nCopy = MIN(nRead, (JOURNAL_CHUNKSIZE - iChunkOffset));
+    memcpy(zOut, &pChunk->zChunk[iChunkOffset], nCopy);
+    zOut += nCopy;
+    nRead -= iSpace;
+    iChunkOffset = 0;
+  } while( nRead>=0 && (pChunk=pChunk->pNext)!=0 && nRead>0 );
+  p->readpoint.iOffset = iOfst+iAmt;
+  p->readpoint.pChunk = pChunk;
 
-  if( 
-      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
-      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
-      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
-  ){
-    pParse->nErr++;
-    goto attach_end;
-  }
+  return SQLITE_OK;
+}
 
-  v = sqlite3GetVdbe(pParse);
-  regArgs = sqlite3GetTempRange(pParse, 4);
-  sqlite3ExprCode(pParse, pFilename, regArgs);
-  sqlite3ExprCode(pParse, pDbname, regArgs+1);
-  sqlite3ExprCode(pParse, pKey, regArgs+2);
+/*
+** Write data to the file.
+*/
+static int memjrnlWrite(
+  sqlite3_file *pJfd,    /* The journal file into which to write */
+  const void *zBuf,      /* Take data to be written from here */
+  int iAmt,              /* Number of bytes to write */
+  sqlite_int64 iOfst     /* Begin writing at this offset into the file */
+){
+  MemJournal *p = (MemJournal *)pJfd;
+  int nWrite = iAmt;
+  u8 *zWrite = (u8 *)zBuf;
+
+  /* An in-memory journal file should only ever be appended to. Random
+  ** access writes are not required by sqlite.
+  */
+  assert( iOfst==p->endpoint.iOffset );
+  UNUSED_PARAMETER(iOfst);
+
+  while( nWrite>0 ){
+    FileChunk *pChunk = p->endpoint.pChunk;
+    int iChunkOffset = (int)(p->endpoint.iOffset%JOURNAL_CHUNKSIZE);
+    int iSpace = MIN(nWrite, JOURNAL_CHUNKSIZE - iChunkOffset);
+
+    if( iChunkOffset==0 ){
+      /* New chunk is required to extend the file. */
+      FileChunk *pNew = sqlite3_malloc(sizeof(FileChunk));
+      if( !pNew ){
+        return SQLITE_IOERR_NOMEM;
+      }
+      pNew->pNext = 0;
+      if( pChunk ){
+        assert( p->pFirst );
+        pChunk->pNext = pNew;
+      }else{
+        assert( !p->pFirst );
+        p->pFirst = pNew;
+      }
+      p->endpoint.pChunk = pNew;
+    }
 
-  assert( v || db->mallocFailed );
-  if( v ){
-    sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-nFunc, regArgs+3);
-    sqlite3VdbeChangeP5(v, nFunc);
-    pFunc = sqlite3FindFunction(db, zFunc, strlen(zFunc), nFunc, SQLITE_UTF8,0);
-    sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
+    memcpy(&p->endpoint.pChunk->zChunk[iChunkOffset], zWrite, iSpace);
+    zWrite += iSpace;
+    nWrite -= iSpace;
+    p->endpoint.iOffset += iSpace;
+  }
 
-    /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
-    ** statement only). For DETACH, set it to false (expire all existing
-    ** statements).
-    */
-    sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
+  return SQLITE_OK;
+}
+
+/*
+** Truncate the file.
+*/
+static int memjrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
+  MemJournal *p = (MemJournal *)pJfd;
+  FileChunk *pChunk;
+  assert(size==0);
+  UNUSED_PARAMETER(size);
+  pChunk = p->pFirst;
+  while( pChunk ){
+    FileChunk *pTmp = pChunk;
+    pChunk = pChunk->pNext;
+    sqlite3_free(pTmp);
   }
-  
-attach_end:
-  sqlite3ExprDelete(pFilename);
-  sqlite3ExprDelete(pDbname);
-  sqlite3ExprDelete(pKey);
+  sqlite3MemJournalOpen(pJfd);
+  return SQLITE_OK;
 }
 
 /*
-** Called by the parser to compile a DETACH statement.
-**
-**     DETACH pDbname
+** Close the file.
 */
-SQLITE_PRIVATE void sqlite3Detach(Parse *pParse, Expr *pDbname){
-  codeAttach(pParse, SQLITE_DETACH, "sqlite_detach", 1, pDbname, 0, 0, pDbname);
+static int memjrnlClose(sqlite3_file *pJfd){
+  memjrnlTruncate(pJfd, 0);
+  return SQLITE_OK;
 }
 
+
 /*
-** Called by the parser to compile an ATTACH statement.
+** Sync the file.
 **
-**     ATTACH p AS pDbname KEY pKey
+** Syncing an in-memory journal is a no-op.  And, in fact, this routine
+** is never called in a working implementation.  This implementation
+** exists purely as a contingency, in case some malfunction in some other
+** part of SQLite causes Sync to be called by mistake.
 */
-SQLITE_PRIVATE void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){
-  codeAttach(pParse, SQLITE_ATTACH, "sqlite_attach", 3, p, p, pDbname, pKey);
+static int memjrnlSync(sqlite3_file *NotUsed, int NotUsed2){   /*NO_TEST*/
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);                        /*NO_TEST*/
+  assert( 0 );                                                 /*NO_TEST*/
+  return SQLITE_OK;                                            /*NO_TEST*/
+}                                                              /*NO_TEST*/
+
+/*
+** Query the size of the file in bytes.
+*/
+static int memjrnlFileSize(sqlite3_file *pJfd, sqlite_int64 *pSize){
+  MemJournal *p = (MemJournal *)pJfd;
+  *pSize = (sqlite_int64) p->endpoint.iOffset;
+  return SQLITE_OK;
 }
-#endif /* SQLITE_OMIT_ATTACH */
 
 /*
-** Register the functions sqlite_attach and sqlite_detach.
+** Table of methods for MemJournal sqlite3_file object.
 */
-SQLITE_PRIVATE void sqlite3AttachFunctions(sqlite3 *db){
-#ifndef SQLITE_OMIT_ATTACH
-  static const int enc = SQLITE_UTF8;
-  sqlite3CreateFunc(db, "sqlite_attach", 3, enc, 0, attachFunc, 0, 0);
-  sqlite3CreateFunc(db, "sqlite_detach", 1, enc, 0, detachFunc, 0, 0);
-#endif
+static struct sqlite3_io_methods MemJournalMethods = {
+  1,                /* iVersion */
+  memjrnlClose,     /* xClose */
+  memjrnlRead,      /* xRead */
+  memjrnlWrite,     /* xWrite */
+  memjrnlTruncate,  /* xTruncate */
+  memjrnlSync,      /* xSync */
+  memjrnlFileSize,  /* xFileSize */
+  0,                /* xLock */
+  0,                /* xUnlock */
+  0,                /* xCheckReservedLock */
+  0,                /* xFileControl */
+  0,                /* xSectorSize */
+  0                 /* xDeviceCharacteristics */
+};
+
+/* 
+** Open a journal file.
+*/
+SQLITE_PRIVATE void sqlite3MemJournalOpen(sqlite3_file *pJfd){
+  MemJournal *p = (MemJournal *)pJfd;
+  assert( EIGHT_BYTE_ALIGNMENT(p) );
+  memset(p, 0, sqlite3MemJournalSize());
+  p->pMethod = &MemJournalMethods;
 }
 
 /*
-** Initialize a DbFixer structure.  This routine must be called prior
-** to passing the structure to one of the sqliteFixAAAA() routines below.
-**
-** The return value indicates whether or not fixation is required.  TRUE
-** means we do need to fix the database references, FALSE means we do not.
+** Return true if the file-handle passed as an argument is 
+** an in-memory journal 
 */
-SQLITE_PRIVATE int sqlite3FixInit(
-  DbFixer *pFix,      /* The fixer to be initialized */
-  Parse *pParse,      /* Error messages will be written here */
-  int iDb,            /* This is the database that must be used */
-  const char *zType,  /* "view", "trigger", or "index" */
-  const Token *pName  /* Name of the view, trigger, or index */
-){
-  sqlite3 *db;
+SQLITE_PRIVATE int sqlite3IsMemJournal(sqlite3_file *pJfd){
+  return pJfd->pMethods==&MemJournalMethods;
+}
 
-  if( iDb<0 || iDb==1 ) return 0;
-  db = pParse->db;
-  assert( db->nDb>iDb );
-  pFix->pParse = pParse;
-  pFix->zDb = db->aDb[iDb].zName;
-  pFix->zType = zType;
-  pFix->pName = pName;
-  return 1;
+/* 
+** Return the number of bytes required to store a MemJournal that uses vfs
+** pVfs to create the underlying on-disk files.
+*/
+SQLITE_PRIVATE int sqlite3MemJournalSize(void){
+  return sizeof(MemJournal);
 }
 
+/************** End of memjournal.c ******************************************/
+/************** Begin file walker.c ******************************************/
 /*
-** The following set of routines walk through the parse tree and assign
-** a specific database to all table references where the database name
-** was left unspecified in the original SQL statement.  The pFix structure
-** must have been initialized by a prior call to sqlite3FixInit().
+** 2008 August 16
 **
-** These routines are used to make sure that an index, trigger, or
-** view in one database does not refer to objects in a different database.
-** (Exception: indices, triggers, and views in the TEMP database are
-** allowed to refer to anything.)  If a reference is explicitly made
-** to an object in a different database, an error message is added to
-** pParse->zErrMsg and these routines return non-zero.  If everything
-** checks out, these routines return 0.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains routines used for walking the parser tree for
+** an SQL statement.
+**
+** $Id: walker.c,v 1.7 2009/06/15 23:15:59 drh Exp $
 */
-SQLITE_PRIVATE int sqlite3FixSrcList(
-  DbFixer *pFix,       /* Context of the fixation */
-  SrcList *pList       /* The Source list to check and modify */
-){
-  int i;
-  const char *zDb;
-  struct SrcList_item *pItem;
 
-  if( pList==0 ) return 0;
-  zDb = pFix->zDb;
-  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
-    if( pItem->zDatabase==0 ){
-      pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb);
-    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
-      sqlite3ErrorMsg(pFix->pParse,
-         "%s %T cannot reference objects in database %s",
-         pFix->zType, pFix->pName, pItem->zDatabase);
-      return 1;
+
+/*
+** Walk an expression tree.  Invoke the callback once for each node
+** of the expression, while decending.  (In other words, the callback
+** is invoked before visiting children.)
+**
+** The return value from the callback should be one of the WRC_*
+** constants to specify how to proceed with the walk.
+**
+**    WRC_Continue      Continue descending down the tree.
+**
+**    WRC_Prune         Do not descend into child nodes.  But allow
+**                      the walk to continue with sibling nodes.
+**
+**    WRC_Abort         Do no more callbacks.  Unwind the stack and
+**                      return the top-level walk call.
+**
+** The return value from this routine is WRC_Abort to abandon the tree walk
+** and WRC_Continue to continue.
+*/
+SQLITE_PRIVATE int sqlite3WalkExpr(Walker *pWalker, Expr *pExpr){
+  int rc;
+  if( pExpr==0 ) return WRC_Continue;
+  testcase( ExprHasProperty(pExpr, EP_TokenOnly) );
+  testcase( ExprHasProperty(pExpr, EP_Reduced) );
+  rc = pWalker->xExprCallback(pWalker, pExpr);
+  if( rc==WRC_Continue
+              && !ExprHasAnyProperty(pExpr,EP_TokenOnly) ){
+    if( sqlite3WalkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort;
+    if( sqlite3WalkExpr(pWalker, pExpr->pRight) ) return WRC_Abort;
+    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+      if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
+    }else{
+      if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
     }
-#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
-    if( sqlite3FixSelect(pFix, pItem->pSelect) ) return 1;
-    if( sqlite3FixExpr(pFix, pItem->pOn) ) return 1;
-#endif
   }
-  return 0;
+  return rc & WRC_Abort;
 }
-#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
-SQLITE_PRIVATE int sqlite3FixSelect(
-  DbFixer *pFix,       /* Context of the fixation */
-  Select *pSelect      /* The SELECT statement to be fixed to one database */
-){
-  while( pSelect ){
-    if( sqlite3FixExprList(pFix, pSelect->pEList) ){
-      return 1;
-    }
-    if( sqlite3FixSrcList(pFix, pSelect->pSrc) ){
-      return 1;
-    }
-    if( sqlite3FixExpr(pFix, pSelect->pWhere) ){
-      return 1;
-    }
-    if( sqlite3FixExpr(pFix, pSelect->pHaving) ){
-      return 1;
-    }
-    pSelect = pSelect->pPrior;
-  }
-  return 0;
-}
-SQLITE_PRIVATE int sqlite3FixExpr(
-  DbFixer *pFix,     /* Context of the fixation */
-  Expr *pExpr        /* The expression to be fixed to one database */
-){
-  while( pExpr ){
-    if( sqlite3FixSelect(pFix, pExpr->pSelect) ){
-      return 1;
-    }
-    if( sqlite3FixExprList(pFix, pExpr->pList) ){
-      return 1;
-    }
-    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
-      return 1;
-    }
-    pExpr = pExpr->pLeft;
-  }
-  return 0;
-}
-SQLITE_PRIVATE int sqlite3FixExprList(
-  DbFixer *pFix,     /* Context of the fixation */
-  ExprList *pList    /* The expression to be fixed to one database */
-){
+
+/*
+** Call sqlite3WalkExpr() for every expression in list p or until
+** an abort request is seen.
+*/
+SQLITE_PRIVATE int sqlite3WalkExprList(Walker *pWalker, ExprList *p){
   int i;
   struct ExprList_item *pItem;
-  if( pList==0 ) return 0;
-  for(i=0, pItem=pList->a; i<pList->nExpr; i++, pItem++){
-    if( sqlite3FixExpr(pFix, pItem->pExpr) ){
-      return 1;
-    }
-  }
-  return 0;
-}
-#endif
-
-#ifndef SQLITE_OMIT_TRIGGER
-SQLITE_PRIVATE int sqlite3FixTriggerStep(
-  DbFixer *pFix,     /* Context of the fixation */
-  TriggerStep *pStep /* The trigger step be fixed to one database */
-){
-  while( pStep ){
-    if( sqlite3FixSelect(pFix, pStep->pSelect) ){
-      return 1;
-    }
-    if( sqlite3FixExpr(pFix, pStep->pWhere) ){
-      return 1;
-    }
-    if( sqlite3FixExprList(pFix, pStep->pExprList) ){
-      return 1;
+  if( p ){
+    for(i=p->nExpr, pItem=p->a; i>0; i--, pItem++){
+      if( sqlite3WalkExpr(pWalker, pItem->pExpr) ) return WRC_Abort;
     }
-    pStep = pStep->pNext;
   }
-  return 0;
-}
-#endif
-
-/************** End of attach.c **********************************************/
-/************** Begin file auth.c ********************************************/
-/*
-** 2003 January 11
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains code used to implement the sqlite3_set_authorizer()
-** API.  This facility is an optional feature of the library.  Embedded
-** systems that do not need this facility may omit it by recompiling
-** the library with -DSQLITE_OMIT_AUTHORIZATION=1
-**
-** $Id: auth.c,v 1.29 2007/09/18 15:55:07 drh Exp $
-*/
-
-/*
-** All of the code in this file may be omitted by defining a single
-** macro.
-*/
-#ifndef SQLITE_OMIT_AUTHORIZATION
-
-/*
-** Set or clear the access authorization function.
-**
-** The access authorization function is be called during the compilation
-** phase to verify that the user has read and/or write access permission on
-** various fields of the database.  The first argument to the auth function
-** is a copy of the 3rd argument to this routine.  The second argument
-** to the auth function is one of these constants:
-**
-**       SQLITE_CREATE_INDEX
-**       SQLITE_CREATE_TABLE
-**       SQLITE_CREATE_TEMP_INDEX
-**       SQLITE_CREATE_TEMP_TABLE
-**       SQLITE_CREATE_TEMP_TRIGGER
-**       SQLITE_CREATE_TEMP_VIEW
-**       SQLITE_CREATE_TRIGGER
-**       SQLITE_CREATE_VIEW
-**       SQLITE_DELETE
-**       SQLITE_DROP_INDEX
-**       SQLITE_DROP_TABLE
-**       SQLITE_DROP_TEMP_INDEX
-**       SQLITE_DROP_TEMP_TABLE
-**       SQLITE_DROP_TEMP_TRIGGER
-**       SQLITE_DROP_TEMP_VIEW
-**       SQLITE_DROP_TRIGGER
-**       SQLITE_DROP_VIEW
-**       SQLITE_INSERT
-**       SQLITE_PRAGMA
-**       SQLITE_READ
-**       SQLITE_SELECT
-**       SQLITE_TRANSACTION
-**       SQLITE_UPDATE
-**
-** The third and fourth arguments to the auth function are the name of
-** the table and the column that are being accessed.  The auth function
-** should return either SQLITE_OK, SQLITE_DENY, or SQLITE_IGNORE.  If
-** SQLITE_OK is returned, it means that access is allowed.  SQLITE_DENY
-** means that the SQL statement will never-run - the sqlite3_exec() call
-** will return with an error.  SQLITE_IGNORE means that the SQL statement
-** should run but attempts to read the specified column will return NULL
-** and attempts to write the column will be ignored.
-**
-** Setting the auth function to NULL disables this hook.  The default
-** setting of the auth function is NULL.
-*/
-SQLITE_API int sqlite3_set_authorizer(
-  sqlite3 *db,
-  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
-  void *pArg
-){
-  sqlite3_mutex_enter(db->mutex);
-  db->xAuth = xAuth;
-  db->pAuthArg = pArg;
-  sqlite3ExpirePreparedStatements(db);
-  sqlite3_mutex_leave(db->mutex);
-  return SQLITE_OK;
+  return WRC_Continue;
 }
 
 /*
-** Write an error message into pParse->zErrMsg that explains that the
-** user-supplied authorization function returned an illegal value.
+** Walk all expressions associated with SELECT statement p.  Do
+** not invoke the SELECT callback on p, but do (of course) invoke
+** any expr callbacks and SELECT callbacks that come from subqueries.
+** Return WRC_Abort or WRC_Continue.
 */
-static void sqliteAuthBadReturnCode(Parse *pParse, int rc){
-  sqlite3ErrorMsg(pParse, "illegal return value (%d) from the "
-    "authorization function - should be SQLITE_OK, SQLITE_IGNORE, "
-    "or SQLITE_DENY", rc);
-  pParse->rc = SQLITE_ERROR;
+SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker *pWalker, Select *p){
+  if( sqlite3WalkExprList(pWalker, p->pEList) ) return WRC_Abort;
+  if( sqlite3WalkExpr(pWalker, p->pWhere) ) return WRC_Abort;
+  if( sqlite3WalkExprList(pWalker, p->pGroupBy) ) return WRC_Abort;
+  if( sqlite3WalkExpr(pWalker, p->pHaving) ) return WRC_Abort;
+  if( sqlite3WalkExprList(pWalker, p->pOrderBy) ) return WRC_Abort;
+  if( sqlite3WalkExpr(pWalker, p->pLimit) ) return WRC_Abort;
+  if( sqlite3WalkExpr(pWalker, p->pOffset) ) return WRC_Abort;
+  return WRC_Continue;
 }
 
 /*
-** The pExpr should be a TK_COLUMN expression.  The table referred to
-** is in pTabList or else it is the NEW or OLD table of a trigger.  
-** Check to see if it is OK to read this particular column.
-**
-** If the auth function returns SQLITE_IGNORE, change the TK_COLUMN 
-** instruction into a TK_NULL.  If the auth function returns SQLITE_DENY,
-** then generate an error.
+** Walk the parse trees associated with all subqueries in the
+** FROM clause of SELECT statement p.  Do not invoke the select
+** callback on p, but do invoke it on each FROM clause subquery
+** and on any subqueries further down in the tree.  Return 
+** WRC_Abort or WRC_Continue;
 */
-SQLITE_PRIVATE void sqlite3AuthRead(
-  Parse *pParse,        /* The parser context */
-  Expr *pExpr,          /* The expression to check authorization on */
-  Schema *pSchema,      /* The schema of the expression */
-  SrcList *pTabList     /* All table that pExpr might refer to */
-){
-  sqlite3 *db = pParse->db;
-  int rc;
-  Table *pTab = 0;      /* The table being read */
-  const char *zCol;     /* Name of the column of the table */
-  int iSrc;             /* Index in pTabList->a[] of table being read */
-  const char *zDBase;   /* Name of database being accessed */
-  TriggerStack *pStack; /* The stack of current triggers */
-  int iDb;              /* The index of the database the expression refers to */
+SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker *pWalker, Select *p){
+  SrcList *pSrc;
+  int i;
+  struct SrcList_item *pItem;
 
-  if( db->xAuth==0 ) return;
-  if( pExpr->op!=TK_COLUMN ) return;
-  iDb = sqlite3SchemaToIndex(pParse->db, pSchema);
-  if( iDb<0 ){
-    /* An attempt to read a column out of a subquery or other
-    ** temporary table. */
-    return;
-  }
-  for(iSrc=0; pTabList && iSrc<pTabList->nSrc; iSrc++){
-    if( pExpr->iTable==pTabList->a[iSrc].iCursor ) break;
-  }
-  if( iSrc>=0 && pTabList && iSrc<pTabList->nSrc ){
-    pTab = pTabList->a[iSrc].pTab;
-  }else if( (pStack = pParse->trigStack)!=0 ){
-    /* This must be an attempt to read the NEW or OLD pseudo-tables
-    ** of a trigger.
-    */
-    assert( pExpr->iTable==pStack->newIdx || pExpr->iTable==pStack->oldIdx );
-    pTab = pStack->pTab;
-  }
-  if( pTab==0 ) return;
-  if( pExpr->iColumn>=0 ){
-    assert( pExpr->iColumn<pTab->nCol );
-    zCol = pTab->aCol[pExpr->iColumn].zName;
-  }else if( pTab->iPKey>=0 ){
-    assert( pTab->iPKey<pTab->nCol );
-    zCol = pTab->aCol[pTab->iPKey].zName;
-  }else{
-    zCol = "ROWID";
-  }
-  assert( iDb>=0 && iDb<db->nDb );
-  zDBase = db->aDb[iDb].zName;
-  rc = db->xAuth(db->pAuthArg, SQLITE_READ, pTab->zName, zCol, zDBase, 
-                 pParse->zAuthContext);
-  if( rc==SQLITE_IGNORE ){
-    pExpr->op = TK_NULL;
-  }else if( rc==SQLITE_DENY ){
-    if( db->nDb>2 || iDb!=0 ){
-      sqlite3ErrorMsg(pParse, "access to %s.%s.%s is prohibited", 
-         zDBase, pTab->zName, zCol);
-    }else{
-      sqlite3ErrorMsg(pParse, "access to %s.%s is prohibited",pTab->zName,zCol);
+  pSrc = p->pSrc;
+  if( ALWAYS(pSrc) ){
+    for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){
+      if( sqlite3WalkSelect(pWalker, pItem->pSelect) ){
+        return WRC_Abort;
+      }
     }
-    pParse->rc = SQLITE_AUTH;
-  }else if( rc!=SQLITE_OK ){
-    sqliteAuthBadReturnCode(pParse, rc);
   }
-}
+  return WRC_Continue;
+} 
 
 /*
-** Do an authorization check using the code and arguments given.  Return
-** either SQLITE_OK (zero) or SQLITE_IGNORE or SQLITE_DENY.  If SQLITE_DENY
-** is returned, then the error count and error message in pParse are
-** modified appropriately.
+** Call sqlite3WalkExpr() for every expression in Select statement p.
+** Invoke sqlite3WalkSelect() for subqueries in the FROM clause and
+** on the compound select chain, p->pPrior.
+**
+** Return WRC_Continue under normal conditions.  Return WRC_Abort if
+** there is an abort request.
+**
+** If the Walker does not have an xSelectCallback() then this routine
+** is a no-op returning WRC_Continue.
 */
-SQLITE_PRIVATE int sqlite3AuthCheck(
-  Parse *pParse,
-  int code,
-  const char *zArg1,
-  const char *zArg2,
-  const char *zArg3
-){
-  sqlite3 *db = pParse->db;
+SQLITE_PRIVATE int sqlite3WalkSelect(Walker *pWalker, Select *p){
   int rc;
-
-  /* Don't do any authorization checks if the database is initialising
-  ** or if the parser is being invoked from within sqlite3_declare_vtab.
-  */
-  if( db->init.busy || IN_DECLARE_VTAB ){
-    return SQLITE_OK;
-  }
-
-  if( db->xAuth==0 ){
-    return SQLITE_OK;
-  }
-  rc = db->xAuth(db->pAuthArg, code, zArg1, zArg2, zArg3, pParse->zAuthContext);
-  if( rc==SQLITE_DENY ){
-    sqlite3ErrorMsg(pParse, "not authorized");
-    pParse->rc = SQLITE_AUTH;
-  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
-    rc = SQLITE_DENY;
-    sqliteAuthBadReturnCode(pParse, rc);
-  }
-  return rc;
-}
-
-/*
-** Push an authorization context.  After this routine is called, the
-** zArg3 argument to authorization callbacks will be zContext until
-** popped.  Or if pParse==0, this routine is a no-op.
-*/
-SQLITE_PRIVATE void sqlite3AuthContextPush(
-  Parse *pParse,
-  AuthContext *pContext, 
-  const char *zContext
-){
-  pContext->pParse = pParse;
-  if( pParse ){
-    pContext->zAuthContext = pParse->zAuthContext;
-    pParse->zAuthContext = zContext;
-  }
-}
-
-/*
-** Pop an authorization context that was previously pushed
-** by sqlite3AuthContextPush
-*/
-SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext *pContext){
-  if( pContext->pParse ){
-    pContext->pParse->zAuthContext = pContext->zAuthContext;
-    pContext->pParse = 0;
+  if( p==0 || pWalker->xSelectCallback==0 ) return WRC_Continue;
+  rc = WRC_Continue;
+  while( p  ){
+    rc = pWalker->xSelectCallback(pWalker, p);
+    if( rc ) break;
+    if( sqlite3WalkSelectExpr(pWalker, p) ) return WRC_Abort;
+    if( sqlite3WalkSelectFrom(pWalker, p) ) return WRC_Abort;
+    p = p->pPrior;
   }
+  return rc & WRC_Abort;
 }
 
-#endif /* SQLITE_OMIT_AUTHORIZATION */
-
-/************** End of auth.c ************************************************/
-/************** Begin file build.c *******************************************/
+/************** End of walker.c **********************************************/
+/************** Begin file resolve.c *****************************************/
 /*
-** 2001 September 15
+** 2008 August 18
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -52852,4413 +58795,4747 @@ SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext *pContext){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains C code routines that are called by the SQLite parser
-** when syntax rules are reduced.  The routines in this file handle the
-** following kinds of SQL syntax:
 **
-**     CREATE TABLE
-**     DROP TABLE
-**     CREATE INDEX
-**     DROP INDEX
-**     creating ID lists
-**     BEGIN TRANSACTION
-**     COMMIT
-**     ROLLBACK
+** This file contains routines used for walking the parser tree and
+** resolve all identifiers by associating them with a particular
+** table and column.
 **
-** $Id: build.c,v 1.484 2008/05/01 17:16:53 drh Exp $
-*/
-
-/*
-** This routine is called when a new SQL statement is beginning to
-** be parsed.  Initialize the pParse structure as needed.
-*/
-SQLITE_PRIVATE void sqlite3BeginParse(Parse *pParse, int explainFlag){
-  pParse->explain = explainFlag;
-  pParse->nVar = 0;
-}
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-/*
-** The TableLock structure is only used by the sqlite3TableLock() and
-** codeTableLocks() functions.
+** $Id: resolve.c,v 1.30 2009/06/15 23:15:59 drh Exp $
 */
-struct TableLock {
-  int iDb;             /* The database containing the table to be locked */
-  int iTab;            /* The root page of the table to be locked */
-  u8 isWriteLock;      /* True for write lock.  False for a read lock */
-  const char *zName;   /* Name of the table */
-};
 
 /*
-** Record the fact that we want to lock a table at run-time.  
+** Turn the pExpr expression into an alias for the iCol-th column of the
+** result set in pEList.
 **
-** The table to be locked has root page iTab and is found in database iDb.
-** A read or a write lock can be taken depending on isWritelock.
+** If the result set column is a simple column reference, then this routine
+** makes an exact copy.  But for any other kind of expression, this
+** routine make a copy of the result set column as the argument to the
+** TK_AS operator.  The TK_AS operator causes the expression to be
+** evaluated just once and then reused for each alias.
 **
-** This routine just records the fact that the lock is desired.  The
-** code to make the lock occur is generated by a later call to
-** codeTableLocks() which occurs during sqlite3FinishCoding().
+** The reason for suppressing the TK_AS term when the expression is a simple
+** column reference is so that the column reference will be recognized as
+** usable by indices within the WHERE clause processing logic. 
+**
+** Hack:  The TK_AS operator is inhibited if zType[0]=='G'.  This means
+** that in a GROUP BY clause, the expression is evaluated twice.  Hence:
+**
+**     SELECT random()%5 AS x, count(*) FROM tab GROUP BY x
+**
+** Is equivalent to:
+**
+**     SELECT random()%5 AS x, count(*) FROM tab GROUP BY random()%5
+**
+** The result of random()%5 in the GROUP BY clause is probably different
+** from the result in the result-set.  We might fix this someday.  Or
+** then again, we might not...
 */
-SQLITE_PRIVATE void sqlite3TableLock(
-  Parse *pParse,     /* Parsing context */
-  int iDb,           /* Index of the database containing the table to lock */
-  int iTab,          /* Root page number of the table to be locked */
-  u8 isWriteLock,    /* True for a write lock */
-  const char *zName  /* Name of the table to be locked */
+static void resolveAlias(
+  Parse *pParse,         /* Parsing context */
+  ExprList *pEList,      /* A result set */
+  int iCol,              /* A column in the result set.  0..pEList->nExpr-1 */
+  Expr *pExpr,           /* Transform this into an alias to the result set */
+  const char *zType      /* "GROUP" or "ORDER" or "" */
 ){
-  int i;
-  int nBytes;
-  TableLock *p;
-
-  if( iDb<0 ){
-    return;
-  }
-
-  for(i=0; i<pParse->nTableLock; i++){
-    p = &pParse->aTableLock[i];
-    if( p->iDb==iDb && p->iTab==iTab ){
-      p->isWriteLock = (p->isWriteLock || isWriteLock);
-      return;
-    }
-  }
+  Expr *pOrig;           /* The iCol-th column of the result set */
+  Expr *pDup;            /* Copy of pOrig */
+  sqlite3 *db;           /* The database connection */
 
-  nBytes = sizeof(TableLock) * (pParse->nTableLock+1);
-  pParse->aTableLock = 
-      sqlite3DbReallocOrFree(pParse->db, pParse->aTableLock, nBytes);
-  if( pParse->aTableLock ){
-    p = &pParse->aTableLock[pParse->nTableLock++];
-    p->iDb = iDb;
-    p->iTab = iTab;
-    p->isWriteLock = isWriteLock;
-    p->zName = zName;
+  assert( iCol>=0 && iCol<pEList->nExpr );
+  pOrig = pEList->a[iCol].pExpr;
+  assert( pOrig!=0 );
+  assert( pOrig->flags & EP_Resolved );
+  db = pParse->db;
+  if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
+    pDup = sqlite3ExprDup(db, pOrig, 0);
+    pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
+    if( pDup==0 ) return;
+    if( pEList->a[iCol].iAlias==0 ){
+      pEList->a[iCol].iAlias = (u16)(++pParse->nAlias);
+    }
+    pDup->iTable = pEList->a[iCol].iAlias;
+  }else if( ExprHasProperty(pOrig, EP_IntValue) || pOrig->u.zToken==0 ){
+    pDup = sqlite3ExprDup(db, pOrig, 0);
+    if( pDup==0 ) return;
   }else{
-    pParse->nTableLock = 0;
-    pParse->db->mallocFailed = 1;
-  }
-}
-
-/*
-** Code an OP_TableLock instruction for each table locked by the
-** statement (configured by calls to sqlite3TableLock()).
-*/
-static void codeTableLocks(Parse *pParse){
-  int i;
-  Vdbe *pVdbe; 
-
-  if( 0==(pVdbe = sqlite3GetVdbe(pParse)) ){
-    return;
+    char *zToken = pOrig->u.zToken;
+    assert( zToken!=0 );
+    pOrig->u.zToken = 0;
+    pDup = sqlite3ExprDup(db, pOrig, 0);
+    pOrig->u.zToken = zToken;
+    if( pDup==0 ) return;
+    assert( (pDup->flags & (EP_Reduced|EP_TokenOnly))==0 );
+    pDup->flags2 |= EP2_MallocedToken;
+    pDup->u.zToken = sqlite3DbStrDup(db, zToken);
   }
-
-  for(i=0; i<pParse->nTableLock; i++){
-    TableLock *p = &pParse->aTableLock[i];
-    int p1 = p->iDb;
-    sqlite3VdbeAddOp4(pVdbe, OP_TableLock, p1, p->iTab, p->isWriteLock,
-                      p->zName, P4_STATIC);
+  if( pExpr->flags & EP_ExpCollate ){
+    pDup->pColl = pExpr->pColl;
+    pDup->flags |= EP_ExpCollate;
   }
+  sqlite3ExprClear(db, pExpr);
+  memcpy(pExpr, pDup, sizeof(*pExpr));
+  sqlite3DbFree(db, pDup);
 }
-#else
-  #define codeTableLocks(x)
-#endif
 
 /*
-** This routine is called after a single SQL statement has been
-** parsed and a VDBE program to execute that statement has been
-** prepared.  This routine puts the finishing touches on the
-** VDBE program and resets the pParse structure for the next
-** parse.
+** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
+** that name in the set of source tables in pSrcList and make the pExpr 
+** expression node refer back to that source column.  The following changes
+** are made to pExpr:
 **
-** Note that if an error occurred, it might be the case that
-** no VDBE code was generated.
+**    pExpr->iDb           Set the index in db->aDb[] of the database X
+**                         (even if X is implied).
+**    pExpr->iTable        Set to the cursor number for the table obtained
+**                         from pSrcList.
+**    pExpr->pTab          Points to the Table structure of X.Y (even if
+**                         X and/or Y are implied.)
+**    pExpr->iColumn       Set to the column number within the table.
+**    pExpr->op            Set to TK_COLUMN.
+**    pExpr->pLeft         Any expression this points to is deleted
+**    pExpr->pRight        Any expression this points to is deleted.
+**
+** The zDb variable is the name of the database (the "X").  This value may be
+** NULL meaning that name is of the form Y.Z or Z.  Any available database
+** can be used.  The zTable variable is the name of the table (the "Y").  This
+** value can be NULL if zDb is also NULL.  If zTable is NULL it
+** means that the form of the name is Z and that columns from any table
+** can be used.
+**
+** If the name cannot be resolved unambiguously, leave an error message
+** in pParse and return WRC_Abort.  Return WRC_Prune on success.
 */
-SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
-  sqlite3 *db;
-  Vdbe *v;
+static int lookupName(
+  Parse *pParse,       /* The parsing context */
+  const char *zDb,     /* Name of the database containing table, or NULL */
+  const char *zTab,    /* Name of table containing column, or NULL */
+  const char *zCol,    /* Name of the column. */
+  NameContext *pNC,    /* The name context used to resolve the name */
+  Expr *pExpr          /* Make this EXPR node point to the selected column */
+){
+  int i, j;            /* Loop counters */
+  int cnt = 0;                      /* Number of matching column names */
+  int cntTab = 0;                   /* Number of matching table names */
+  sqlite3 *db = pParse->db;         /* The database connection */
+  struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
+  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
+  NameContext *pTopNC = pNC;        /* First namecontext in the list */
+  Schema *pSchema = 0;              /* Schema of the expression */
+  int isTrigger = 0;
 
-  db = pParse->db;
-  if( db->mallocFailed ) return;
-  if( pParse->nested ) return;
-  if( pParse->nErr ) return;
-  if( !pParse->pVdbe ){
-    if( pParse->rc==SQLITE_OK && pParse->nErr ){
-      pParse->rc = SQLITE_ERROR;
-      return;
-    }
-  }
+  assert( pNC );     /* the name context cannot be NULL. */
+  assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
+  assert( ~ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
 
-  /* Begin by generating some termination code at the end of the
-  ** vdbe program
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3VdbeAddOp0(v, OP_Halt);
+  /* Initialize the node to no-match */
+  pExpr->iTable = -1;
+  pExpr->pTab = 0;
+  ExprSetIrreducible(pExpr);
 
-    /* The cookie mask contains one bit for each database file open.
-    ** (Bit 0 is for main, bit 1 is for temp, and so forth.)  Bits are
-    ** set for each database that is used.  Generate code to start a
-    ** transaction on each used database and to verify the schema cookie
-    ** on each used database.
-    */
-    if( pParse->cookieGoto>0 ){
-      u32 mask;
-      int iDb;
-      sqlite3VdbeJumpHere(v, pParse->cookieGoto-1);
-      for(iDb=0, mask=1; iDb<db->nDb; mask<<=1, iDb++){
-        if( (mask & pParse->cookieMask)==0 ) continue;
-        sqlite3VdbeUsesBtree(v, iDb);
-        sqlite3VdbeAddOp2(v,OP_Transaction, iDb, (mask & pParse->writeMask)!=0);
-        sqlite3VdbeAddOp2(v,OP_VerifyCookie, iDb, pParse->cookieValue[iDb]);
-      }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      {
-        int i;
-        for(i=0; i<pParse->nVtabLock; i++){
-          char *vtab = (char *)pParse->apVtabLock[i]->pVtab;
-          sqlite3VdbeAddOp4(v, OP_VBegin, 0, 0, 0, vtab, P4_VTAB);
+  /* Start at the inner-most context and move outward until a match is found */
+  while( pNC && cnt==0 ){
+    ExprList *pEList;
+    SrcList *pSrcList = pNC->pSrcList;
+
+    if( pSrcList ){
+      for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
+        Table *pTab;
+        int iDb;
+        Column *pCol;
+  
+        pTab = pItem->pTab;
+        assert( pTab!=0 && pTab->zName!=0 );
+        iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+        assert( pTab->nCol>0 );
+        if( zTab ){
+          if( pItem->zAlias ){
+            char *zTabName = pItem->zAlias;
+            if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
+          }else{
+            char *zTabName = pTab->zName;
+            if( NEVER(zTabName==0) || sqlite3StrICmp(zTabName, zTab)!=0 ){
+              continue;
+            }
+            if( zDb!=0 && sqlite3StrICmp(db->aDb[iDb].zName, zDb)!=0 ){
+              continue;
+            }
+          }
+        }
+        if( 0==(cntTab++) ){
+          pExpr->iTable = pItem->iCursor;
+          pExpr->pTab = pTab;
+          pSchema = pTab->pSchema;
+          pMatch = pItem;
+        }
+        for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
+          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
+            IdList *pUsing;
+            cnt++;
+            pExpr->iTable = pItem->iCursor;
+            pExpr->pTab = pTab;
+            pMatch = pItem;
+            pSchema = pTab->pSchema;
+            /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
+            pExpr->iColumn = j==pTab->iPKey ? -1 : (i16)j;
+            if( i<pSrcList->nSrc-1 ){
+              if( pItem[1].jointype & JT_NATURAL ){
+                /* If this match occurred in the left table of a natural join,
+                ** then skip the right table to avoid a duplicate match */
+                pItem++;
+                i++;
+              }else if( (pUsing = pItem[1].pUsing)!=0 ){
+                /* If this match occurs on a column that is in the USING clause
+                ** of a join, skip the search of the right table of the join
+                ** to avoid a duplicate match there. */
+                int k;
+                for(k=0; k<pUsing->nId; k++){
+                  if( sqlite3StrICmp(pUsing->a[k].zName, zCol)==0 ){
+                    pItem++;
+                    i++;
+                    break;
+                  }
+                }
+              }
+            }
+            break;
+          }
         }
-        pParse->nVtabLock = 0;
       }
-#endif
-
-      /* Once all the cookies have been verified and transactions opened, 
-      ** obtain the required table-locks. This is a no-op unless the 
-      ** shared-cache feature is enabled.
-      */
-      codeTableLocks(pParse);
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->cookieGoto);
     }
 
-#ifndef SQLITE_OMIT_TRACE
-    if( !db->init.busy ){
-      /* Change the P4 argument of the first opcode (which will always be
-      ** an OP_Trace) to be the complete text of the current SQL statement.
-      */
-      VdbeOp *pOp = sqlite3VdbeGetOp(v, 0);
-      if( pOp && pOp->opcode==OP_Trace ){
-        sqlite3VdbeChangeP4(v, 0, pParse->zSql, pParse->zTail-pParse->zSql);
+#ifndef SQLITE_OMIT_TRIGGER
+    /* If we have not already resolved the name, then maybe 
+    ** it is a new.* or old.* trigger argument reference
+    */
+    if( zDb==0 && zTab!=0 && cnt==0 && pParse->pTriggerTab!=0 ){
+      int op = pParse->eTriggerOp;
+      Table *pTab = 0;
+      assert( op==TK_DELETE || op==TK_UPDATE || op==TK_INSERT );
+      if( op!=TK_DELETE && sqlite3StrICmp("new",zTab) == 0 ){
+        pExpr->iTable = 1;
+        pTab = pParse->pTriggerTab;
+      }else if( op!=TK_INSERT && sqlite3StrICmp("old",zTab)==0 ){
+        pExpr->iTable = 0;
+        pTab = pParse->pTriggerTab;
       }
-    }
-#endif /* SQLITE_OMIT_TRACE */
-  }
-
 
-  /* Get the VDBE program ready for execution
-  */
-  if( v && pParse->nErr==0 && !db->mallocFailed ){
-#ifdef SQLITE_DEBUG
-    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
-    sqlite3VdbeTrace(v, trace);
-#endif
-    assert( pParse->disableColCache==0 );  /* Disables and re-enables match */
-    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
-                         pParse->nTab+3, pParse->explain);
-    pParse->rc = SQLITE_DONE;
-    pParse->colNamesSet = 0;
-  }else if( pParse->rc==SQLITE_OK ){
-    pParse->rc = SQLITE_ERROR;
-  }
-  pParse->nTab = 0;
-  pParse->nMem = 0;
-  pParse->nSet = 0;
-  pParse->nVar = 0;
-  pParse->cookieMask = 0;
-  pParse->cookieGoto = 0;
-}
+      if( pTab ){ 
+        int iCol;
+        pSchema = pTab->pSchema;
+        cntTab++;
+        if( sqlite3IsRowid(zCol) ){
+          iCol = -1;
+        }else{
+          for(iCol=0; iCol<pTab->nCol; iCol++){
+            Column *pCol = &pTab->aCol[iCol];
+            if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
+              if( iCol==pTab->iPKey ){
+                iCol = -1;
+              }
+              break;
+            }
+          }
+        }
+        if( iCol<pTab->nCol ){
+          cnt++;
+          if( iCol<0 ){
+            pExpr->affinity = SQLITE_AFF_INTEGER;
+          }else if( pExpr->iTable==0 ){
+            testcase( iCol==31 );
+            testcase( iCol==32 );
+            pParse->oldmask |= (iCol>=32 ? 0xffffffff : (((u32)1)<<iCol));
+          }
+          pExpr->iColumn = (i16)iCol;
+          pExpr->pTab = pTab;
+          isTrigger = 1;
+        }
+      }
+    }
+#endif /* !defined(SQLITE_OMIT_TRIGGER) */
 
-/*
-** Run the parser and code generator recursively in order to generate
-** code for the SQL statement given onto the end of the pParse context
-** currently under construction.  When the parser is run recursively
-** this way, the final OP_Halt is not appended and other initialization
-** and finalization steps are omitted because those are handling by the
-** outermost parser.
-**
-** Not everything is nestable.  This facility is designed to permit
-** INSERT, UPDATE, and DELETE operations against SQLITE_MASTER.  Use
-** care if you decide to try to use this routine for some other purposes.
-*/
-SQLITE_PRIVATE void sqlite3NestedParse(Parse *pParse, const char *zFormat, ...){
-  va_list ap;
-  char *zSql;
-# define SAVE_SZ  (sizeof(Parse) - offsetof(Parse,nVar))
-  char saveBuf[SAVE_SZ];
+    /*
+    ** Perhaps the name is a reference to the ROWID
+    */
+    if( cnt==0 && cntTab==1 && sqlite3IsRowid(zCol) ){
+      cnt = 1;
+      pExpr->iColumn = -1;
+      pExpr->affinity = SQLITE_AFF_INTEGER;
+    }
 
-  if( pParse->nErr ) return;
-  assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
-  va_start(ap, zFormat);
-  zSql = sqlite3VMPrintf(pParse->db, zFormat, ap);
-  va_end(ap);
-  if( zSql==0 ){
-    pParse->db->mallocFailed = 1;
-    return;   /* A malloc must have failed */
-  }
-  pParse->nested++;
-  memcpy(saveBuf, &pParse->nVar, SAVE_SZ);
-  memset(&pParse->nVar, 0, SAVE_SZ);
-  sqlite3RunParser(pParse, zSql, 0);
-  sqlite3_free(zSql);
-  memcpy(&pParse->nVar, saveBuf, SAVE_SZ);
-  pParse->nested--;
-}
+    /*
+    ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z
+    ** might refer to an result-set alias.  This happens, for example, when
+    ** we are resolving names in the WHERE clause of the following command:
+    **
+    **     SELECT a+b AS x FROM table WHERE x<10;
+    **
+    ** In cases like this, replace pExpr with a copy of the expression that
+    ** forms the result set entry ("a+b" in the example) and return immediately.
+    ** Note that the expression in the result set should have already been
+    ** resolved by the time the WHERE clause is resolved.
+    */
+    if( cnt==0 && (pEList = pNC->pEList)!=0 && zTab==0 ){
+      for(j=0; j<pEList->nExpr; j++){
+        char *zAs = pEList->a[j].zName;
+        if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
+          Expr *pOrig;
+          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
+          assert( pExpr->x.pList==0 );
+          assert( pExpr->x.pSelect==0 );
+          pOrig = pEList->a[j].pExpr;
+          if( !pNC->allowAgg && ExprHasProperty(pOrig, EP_Agg) ){
+            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
+            return WRC_Abort;
+          }
+          resolveAlias(pParse, pEList, j, pExpr, "");
+          cnt = 1;
+          pMatch = 0;
+          assert( zTab==0 && zDb==0 );
+          goto lookupname_end;
+        }
+      } 
+    }
 
-/*
-** Locate the in-memory structure that describes a particular database
-** table given the name of that table and (optionally) the name of the
-** database containing the table.  Return NULL if not found.
-**
-** If zDatabase is 0, all databases are searched for the table and the
-** first matching table is returned.  (No checking for duplicate table
-** names is done.)  The search order is TEMP first, then MAIN, then any
-** auxiliary databases added using the ATTACH command.
-**
-** See also sqlite3LocateTable().
-*/
-SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
-  Table *p = 0;
-  int i;
-  assert( zName!=0 );
-  for(i=OMIT_TEMPDB; i<db->nDb; i++){
-    int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
-    if( zDatabase!=0 && sqlite3StrICmp(zDatabase, db->aDb[j].zName) ) continue;
-    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName, strlen(zName)+1);
-    if( p ) break;
+    /* Advance to the next name context.  The loop will exit when either
+    ** we have a match (cnt>0) or when we run out of name contexts.
+    */
+    if( cnt==0 ){
+      pNC = pNC->pNext;
+    }
   }
-  return p;
-}
-
-/*
-** Locate the in-memory structure that describes a particular database
-** table given the name of that table and (optionally) the name of the
-** database containing the table.  Return NULL if not found.  Also leave an
-** error message in pParse->zErrMsg.
-**
-** The difference between this routine and sqlite3FindTable() is that this
-** routine leaves an error message in pParse->zErrMsg where
-** sqlite3FindTable() does not.
-*/
-SQLITE_PRIVATE Table *sqlite3LocateTable(
-  Parse *pParse,         /* context in which to report errors */
-  int isView,            /* True if looking for a VIEW rather than a TABLE */
-  const char *zName,     /* Name of the table we are looking for */
-  const char *zDbase     /* Name of the database.  Might be NULL */
-){
-  Table *p;
 
-  /* Read the database schema. If an error occurs, leave an error message
-  ** and code in pParse and return NULL. */
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-    return 0;
+  /*
+  ** If X and Y are NULL (in other words if only the column name Z is
+  ** supplied) and the value of Z is enclosed in double-quotes, then
+  ** Z is a string literal if it doesn't match any column names.  In that
+  ** case, we need to return right away and not make any changes to
+  ** pExpr.
+  **
+  ** Because no reference was made to outer contexts, the pNC->nRef
+  ** fields are not changed in any context.
+  */
+  if( cnt==0 && zTab==0 && ExprHasProperty(pExpr,EP_DblQuoted) ){
+    pExpr->op = TK_STRING;
+    pExpr->pTab = 0;
+    return WRC_Prune;
   }
 
-  p = sqlite3FindTable(pParse->db, zName, zDbase);
-  if( p==0 ){
-    const char *zMsg = isView ? "no such view" : "no such table";
-    if( zDbase ){
-      sqlite3ErrorMsg(pParse, "%s: %s.%s", zMsg, zDbase, zName);
+  /*
+  ** cnt==0 means there was not match.  cnt>1 means there were two or
+  ** more matches.  Either way, we have an error.
+  */
+  if( cnt!=1 ){
+    const char *zErr;
+    zErr = cnt==0 ? "no such column" : "ambiguous column name";
+    if( zDb ){
+      sqlite3ErrorMsg(pParse, "%s: %s.%s.%s", zErr, zDb, zTab, zCol);
+    }else if( zTab ){
+      sqlite3ErrorMsg(pParse, "%s: %s.%s", zErr, zTab, zCol);
     }else{
-      sqlite3ErrorMsg(pParse, "%s: %s", zMsg, zName);
+      sqlite3ErrorMsg(pParse, "%s: %s", zErr, zCol);
     }
-    pParse->checkSchema = 1;
+    pTopNC->nErr++;
   }
-  return p;
-}
 
-/*
-** Locate the in-memory structure that describes 
-** a particular index given the name of that index
-** and the name of the database that contains the index.
-** Return NULL if not found.
-**
-** If zDatabase is 0, all databases are searched for the
-** table and the first matching index is returned.  (No checking
-** for duplicate index names is done.)  The search order is
-** TEMP first, then MAIN, then any auxiliary databases added
-** using the ATTACH command.
-*/
-SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const char *zDb){
-  Index *p = 0;
-  int i;
-  for(i=OMIT_TEMPDB; i<db->nDb; i++){
-    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
-    Schema *pSchema = db->aDb[j].pSchema;
-    if( zDb && sqlite3StrICmp(zDb, db->aDb[j].zName) ) continue;
-    assert( pSchema || (j==1 && !db->aDb[1].pBt) );
-    if( pSchema ){
-      p = sqlite3HashFind(&pSchema->idxHash, zName, strlen(zName)+1);
+  /* If a column from a table in pSrcList is referenced, then record
+  ** this fact in the pSrcList.a[].colUsed bitmask.  Column 0 causes
+  ** bit 0 to be set.  Column 1 sets bit 1.  And so forth.  If the
+  ** column number is greater than the number of bits in the bitmask
+  ** then set the high-order bit of the bitmask.
+  */
+  if( pExpr->iColumn>=0 && pMatch!=0 ){
+    int n = pExpr->iColumn;
+    testcase( n==BMS-1 );
+    if( n>=BMS ){
+      n = BMS-1;
     }
-    if( p ) break;
+    assert( pMatch->iCursor==pExpr->iTable );
+    pMatch->colUsed |= ((Bitmask)1)<<n;
   }
-  return p;
-}
 
-/*
-** Reclaim the memory used by an index
-*/
-static void freeIndex(Index *p){
-  sqlite3_free(p->zColAff);
-  sqlite3_free(p);
+  /* Clean up and return
+  */
+  sqlite3ExprDelete(db, pExpr->pLeft);
+  pExpr->pLeft = 0;
+  sqlite3ExprDelete(db, pExpr->pRight);
+  pExpr->pRight = 0;
+  pExpr->op = (isTrigger ? TK_TRIGGER : TK_COLUMN);
+lookupname_end:
+  if( cnt==1 ){
+    assert( pNC!=0 );
+    sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
+    /* Increment the nRef value on all name contexts from TopNC up to
+    ** the point where the name matched. */
+    for(;;){
+      assert( pTopNC!=0 );
+      pTopNC->nRef++;
+      if( pTopNC==pNC ) break;
+      pTopNC = pTopNC->pNext;
+    }
+    return WRC_Prune;
+  } else {
+    return WRC_Abort;
+  }
 }
 
 /*
-** Remove the given index from the index hash table, and free
-** its memory structures.
+** This routine is callback for sqlite3WalkExpr().
 **
-** The index is removed from the database hash tables but
-** it is not unlinked from the Table that it indexes.
-** Unlinking from the Table must be done by the calling function.
+** Resolve symbolic names into TK_COLUMN operators for the current
+** node in the expression tree.  Return 0 to continue the search down
+** the tree or 2 to abort the tree walk.
+**
+** This routine also does error checking and name resolution for
+** function names.  The operator for aggregate functions is changed
+** to TK_AGG_FUNCTION.
 */
-static void sqliteDeleteIndex(Index *p){
-  Index *pOld;
-  const char *zName = p->zName;
-
-  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName, strlen( zName)+1, 0);
-  assert( pOld==0 || pOld==p );
-  freeIndex(p);
-}
+static int resolveExprStep(Walker *pWalker, Expr *pExpr){
+  NameContext *pNC;
+  Parse *pParse;
 
-/*
-** For the index called zIdxName which is found in the database iDb,
-** unlike that index from its Table then remove the index from
-** the index hash table and free all memory structures associated
-** with the index.
-*/
-SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
-  Index *pIndex;
-  int len;
-  Hash *pHash = &db->aDb[iDb].pSchema->idxHash;
+  pNC = pWalker->u.pNC;
+  assert( pNC!=0 );
+  pParse = pNC->pParse;
+  assert( pParse==pWalker->pParse );
 
-  len = strlen(zIdxName);
-  pIndex = sqlite3HashInsert(pHash, zIdxName, len+1, 0);
-  if( pIndex ){
-    if( pIndex->pTable->pIndex==pIndex ){
-      pIndex->pTable->pIndex = pIndex->pNext;
-    }else{
-      Index *p;
-      for(p=pIndex->pTable->pIndex; p && p->pNext!=pIndex; p=p->pNext){}
-      if( p && p->pNext==pIndex ){
-        p->pNext = pIndex->pNext;
-      }
+  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return WRC_Prune;
+  ExprSetProperty(pExpr, EP_Resolved);
+#ifndef NDEBUG
+  if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){
+    SrcList *pSrcList = pNC->pSrcList;
+    int i;
+    for(i=0; i<pNC->pSrcList->nSrc; i++){
+      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
     }
-    freeIndex(pIndex);
   }
-  db->flags |= SQLITE_InternChanges;
-}
+#endif
+  switch( pExpr->op ){
 
-/*
-** Erase all schema information from the in-memory hash tables of
-** a single database.  This routine is called to reclaim memory
-** before the database closes.  It is also called during a rollback
-** if there were schema changes during the transaction or if a
-** schema-cookie mismatch occurs.
-**
-** If iDb<=0 then reset the internal schema tables for all database
-** files.  If iDb>=2 then reset the internal schema for only the
-** single file indicated.
-*/
-SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
-  int i, j;
-  assert( iDb>=0 && iDb<db->nDb );
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+    /* The special operator TK_ROW means use the rowid for the first
+    ** column in the FROM clause.  This is used by the LIMIT and ORDER BY
+    ** clause processing on UPDATE and DELETE statements.
+    */
+    case TK_ROW: {
+      SrcList *pSrcList = pNC->pSrcList;
+      struct SrcList_item *pItem;
+      assert( pSrcList && pSrcList->nSrc==1 );
+      pItem = pSrcList->a; 
+      pExpr->op = TK_COLUMN;
+      pExpr->pTab = pItem->pTab;
+      pExpr->iTable = pItem->iCursor;
+      pExpr->iColumn = -1;
+      pExpr->affinity = SQLITE_AFF_INTEGER;
+      break;
+    }
+#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
 
-  if( iDb==0 ){
-    sqlite3BtreeEnterAll(db);
-  }
-  for(i=iDb; i<db->nDb; i++){
-    Db *pDb = &db->aDb[i];
-    if( pDb->pSchema ){
-      assert(i==1 || (pDb->pBt && sqlite3BtreeHoldsMutex(pDb->pBt)));
-      sqlite3SchemaFree(pDb->pSchema);
+    /* A lone identifier is the name of a column.
+    */
+    case TK_ID: {
+      return lookupName(pParse, 0, 0, pExpr->u.zToken, pNC, pExpr);
     }
-    if( iDb>0 ) return;
-  }
-  assert( iDb==0 );
-  db->flags &= ~SQLITE_InternChanges;
-  sqlite3BtreeLeaveAll(db);
+  
+    /* A table name and column name:     ID.ID
+    ** Or a database, table and column:  ID.ID.ID
+    */
+    case TK_DOT: {
+      const char *zColumn;
+      const char *zTable;
+      const char *zDb;
+      Expr *pRight;
 
-  /* If one or more of the auxiliary database files has been closed,
-  ** then remove them from the auxiliary database list.  We take the
-  ** opportunity to do this here since we have just deleted all of the
-  ** schema hash tables and therefore do not have to make any changes
-  ** to any of those tables.
-  */
-  for(i=0; i<db->nDb; i++){
-    struct Db *pDb = &db->aDb[i];
-    if( pDb->pBt==0 ){
-      if( pDb->pAux && pDb->xFreeAux ) pDb->xFreeAux(pDb->pAux);
-      pDb->pAux = 0;
+      /* if( pSrcList==0 ) break; */
+      pRight = pExpr->pRight;
+      if( pRight->op==TK_ID ){
+        zDb = 0;
+        zTable = pExpr->pLeft->u.zToken;
+        zColumn = pRight->u.zToken;
+      }else{
+        assert( pRight->op==TK_DOT );
+        zDb = pExpr->pLeft->u.zToken;
+        zTable = pRight->pLeft->u.zToken;
+        zColumn = pRight->pRight->u.zToken;
+      }
+      return lookupName(pParse, zDb, zTable, zColumn, pNC, pExpr);
     }
-  }
-  for(i=j=2; i<db->nDb; i++){
-    struct Db *pDb = &db->aDb[i];
-    if( pDb->pBt==0 ){
-      sqlite3_free(pDb->zName);
-      pDb->zName = 0;
-      continue;
+
+    /* Resolve function names
+    */
+    case TK_CONST_FUNC:
+    case TK_FUNCTION: {
+      ExprList *pList = pExpr->x.pList;    /* The argument list */
+      int n = pList ? pList->nExpr : 0;    /* Number of arguments */
+      int no_such_func = 0;       /* True if no such function exists */
+      int wrong_num_args = 0;     /* True if wrong number of arguments */
+      int is_agg = 0;             /* True if is an aggregate function */
+      int auth;                   /* Authorization to use the function */
+      int nId;                    /* Number of characters in function name */
+      const char *zId;            /* The function name. */
+      FuncDef *pDef;              /* Information about the function */
+      u8 enc = ENC(pParse->db);   /* The database encoding */
+
+      testcase( pExpr->op==TK_CONST_FUNC );
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      zId = pExpr->u.zToken;
+      nId = sqlite3Strlen30(zId);
+      pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
+      if( pDef==0 ){
+        pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, enc, 0);
+        if( pDef==0 ){
+          no_such_func = 1;
+        }else{
+          wrong_num_args = 1;
+        }
+      }else{
+        is_agg = pDef->xFunc==0;
+      }
+#ifndef SQLITE_OMIT_AUTHORIZATION
+      if( pDef ){
+        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);
+        if( auth!=SQLITE_OK ){
+          if( auth==SQLITE_DENY ){
+            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",
+                                    pDef->zName);
+            pNC->nErr++;
+          }
+          pExpr->op = TK_NULL;
+          return WRC_Prune;
+        }
+      }
+#endif
+      if( is_agg && !pNC->allowAgg ){
+        sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId);
+        pNC->nErr++;
+        is_agg = 0;
+      }else if( no_such_func ){
+        sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
+        pNC->nErr++;
+      }else if( wrong_num_args ){
+        sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
+             nId, zId);
+        pNC->nErr++;
+      }
+      if( is_agg ){
+        pExpr->op = TK_AGG_FUNCTION;
+        pNC->hasAgg = 1;
+      }
+      if( is_agg ) pNC->allowAgg = 0;
+      sqlite3WalkExprList(pWalker, pList);
+      if( is_agg ) pNC->allowAgg = 1;
+      /* FIX ME:  Compute pExpr->affinity based on the expected return
+      ** type of the function 
+      */
+      return WRC_Prune;
     }
-    if( j<i ){
-      db->aDb[j] = db->aDb[i];
+#ifndef SQLITE_OMIT_SUBQUERY
+    case TK_SELECT:
+    case TK_EXISTS:  testcase( pExpr->op==TK_EXISTS );
+#endif
+    case TK_IN: {
+      testcase( pExpr->op==TK_IN );
+      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+        int nRef = pNC->nRef;
+#ifndef SQLITE_OMIT_CHECK
+        if( pNC->isCheck ){
+          sqlite3ErrorMsg(pParse,"subqueries prohibited in CHECK constraints");
+        }
+#endif
+        sqlite3WalkSelect(pWalker, pExpr->x.pSelect);
+        assert( pNC->nRef>=nRef );
+        if( nRef!=pNC->nRef ){
+          ExprSetProperty(pExpr, EP_VarSelect);
+        }
+      }
+      break;
     }
-    j++;
-  }
-  memset(&db->aDb[j], 0, (db->nDb-j)*sizeof(db->aDb[j]));
-  db->nDb = j;
-  if( db->nDb<=2 && db->aDb!=db->aDbStatic ){
-    memcpy(db->aDbStatic, db->aDb, 2*sizeof(db->aDb[0]));
-    sqlite3_free(db->aDb);
-    db->aDb = db->aDbStatic;
+#ifndef SQLITE_OMIT_CHECK
+    case TK_VARIABLE: {
+      if( pNC->isCheck ){
+        sqlite3ErrorMsg(pParse,"parameters prohibited in CHECK constraints");
+      }
+      break;
+    }
+#endif
   }
+  return (pParse->nErr || pParse->db->mallocFailed) ? WRC_Abort : WRC_Continue;
 }
 
 /*
-** This routine is called when a commit occurs.
+** pEList is a list of expressions which are really the result set of the
+** a SELECT statement.  pE is a term in an ORDER BY or GROUP BY clause.
+** This routine checks to see if pE is a simple identifier which corresponds
+** to the AS-name of one of the terms of the expression list.  If it is,
+** this routine return an integer between 1 and N where N is the number of
+** elements in pEList, corresponding to the matching entry.  If there is
+** no match, or if pE is not a simple identifier, then this routine
+** return 0.
+**
+** pEList has been resolved.  pE has not.
 */
-SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3 *db){
-  db->flags &= ~SQLITE_InternChanges;
-}
+static int resolveAsName(
+  Parse *pParse,     /* Parsing context for error messages */
+  ExprList *pEList,  /* List of expressions to scan */
+  Expr *pE           /* Expression we are trying to match */
+){
+  int i;             /* Loop counter */
 
-/*
-** Clear the column names from a table or view.
-*/
-static void sqliteResetColumnNames(Table *pTable){
-  int i;
-  Column *pCol;
-  assert( pTable!=0 );
-  if( (pCol = pTable->aCol)!=0 ){
-    for(i=0; i<pTable->nCol; i++, pCol++){
-      sqlite3_free(pCol->zName);
-      sqlite3ExprDelete(pCol->pDflt);
-      sqlite3_free(pCol->zType);
-      sqlite3_free(pCol->zColl);
+  UNUSED_PARAMETER(pParse);
+
+  if( pE->op==TK_ID ){
+    char *zCol = pE->u.zToken;
+    for(i=0; i<pEList->nExpr; i++){
+      char *zAs = pEList->a[i].zName;
+      if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
+        return i+1;
+      }
     }
-    sqlite3_free(pTable->aCol);
   }
-  pTable->aCol = 0;
-  pTable->nCol = 0;
+  return 0;
 }
 
 /*
-** Remove the memory data structures associated with the given
-** Table.  No changes are made to disk by this routine.
+** pE is a pointer to an expression which is a single term in the
+** ORDER BY of a compound SELECT.  The expression has not been
+** name resolved.
 **
-** This routine just deletes the data structure.  It does not unlink
-** the table data structure from the hash table.  Nor does it remove
-** foreign keys from the sqlite.aFKey hash table.  But it does destroy
-** memory structures of the indices and foreign keys associated with 
-** the table.
+** At the point this routine is called, we already know that the
+** ORDER BY term is not an integer index into the result set.  That
+** case is handled by the calling routine.
+**
+** Attempt to match pE against result set columns in the left-most
+** SELECT statement.  Return the index i of the matching column,
+** as an indication to the caller that it should sort by the i-th column.
+** The left-most column is 1.  In other words, the value returned is the
+** same integer value that would be used in the SQL statement to indicate
+** the column.
+**
+** If there is no match, return 0.  Return -1 if an error occurs.
 */
-SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
-  Index *pIndex, *pNext;
-  FKey *pFKey, *pNextFKey;
-
-  if( pTable==0 ) return;
+static int resolveOrderByTermToExprList(
+  Parse *pParse,     /* Parsing context for error messages */
+  Select *pSelect,   /* The SELECT statement with the ORDER BY clause */
+  Expr *pE           /* The specific ORDER BY term */
+){
+  int i;             /* Loop counter */
+  ExprList *pEList;  /* The columns of the result set */
+  NameContext nc;    /* Name context for resolving pE */
 
-  /* Do not delete the table until the reference count reaches zero. */
-  pTable->nRef--;
-  if( pTable->nRef>0 ){
-    return;
-  }
-  assert( pTable->nRef==0 );
+  assert( sqlite3ExprIsInteger(pE, &i)==0 );
+  pEList = pSelect->pEList;
 
-  /* Delete all indices associated with this table
+  /* Resolve all names in the ORDER BY term expression
   */
-  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
-    pNext = pIndex->pNext;
-    assert( pIndex->pSchema==pTable->pSchema );
-    sqliteDeleteIndex(pIndex);
+  memset(&nc, 0, sizeof(nc));
+  nc.pParse = pParse;
+  nc.pSrcList = pSelect->pSrc;
+  nc.pEList = pEList;
+  nc.allowAgg = 1;
+  nc.nErr = 0;
+  if( sqlite3ResolveExprNames(&nc, pE) ){
+    sqlite3ErrorClear(pParse);
+    return 0;
   }
 
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-  /* Delete all foreign keys associated with this table.  The keys
-  ** should have already been unlinked from the pSchema->aFKey hash table 
+  /* Try to match the ORDER BY expression against an expression
+  ** in the result set.  Return an 1-based index of the matching
+  ** result-set entry.
   */
-  for(pFKey=pTable->pFKey; pFKey; pFKey=pNextFKey){
-    pNextFKey = pFKey->pNextFrom;
-    assert( sqlite3HashFind(&pTable->pSchema->aFKey,
-                           pFKey->zTo, strlen(pFKey->zTo)+1)!=pFKey );
-    sqlite3_free(pFKey);
+  for(i=0; i<pEList->nExpr; i++){
+    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE) ){
+      return i+1;
+    }
   }
-#endif
 
-  /* Delete the Table structure itself.
-  */
-  sqliteResetColumnNames(pTable);
-  sqlite3_free(pTable->zName);
-  sqlite3_free(pTable->zColAff);
-  sqlite3SelectDelete(pTable->pSelect);
-#ifndef SQLITE_OMIT_CHECK
-  sqlite3ExprDelete(pTable->pCheck);
-#endif
-  sqlite3VtabClear(pTable);
-  sqlite3_free(pTable);
+  /* If no match, return 0. */
+  return 0;
 }
 
 /*
-** Unlink the given table from the hash tables and the delete the
-** table structure with all its indices and foreign keys.
+** Generate an ORDER BY or GROUP BY term out-of-range error.
 */
-SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3 *db, int iDb, const char *zTabName){
-  Table *p;
-  FKey *pF1, *pF2;
-  Db *pDb;
+static void resolveOutOfRangeError(
+  Parse *pParse,         /* The error context into which to write the error */
+  const char *zType,     /* "ORDER" or "GROUP" */
+  int i,                 /* The index (1-based) of the term out of range */
+  int mx                 /* Largest permissible value of i */
+){
+  sqlite3ErrorMsg(pParse, 
+    "%r %s BY term out of range - should be "
+    "between 1 and %d", i, zType, mx);
+}
 
-  assert( db!=0 );
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( zTabName && zTabName[0] );
-  pDb = &db->aDb[iDb];
-  p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName, strlen(zTabName)+1,0);
-  if( p ){
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-    for(pF1=p->pFKey; pF1; pF1=pF1->pNextFrom){
-      int nTo = strlen(pF1->zTo) + 1;
-      pF2 = sqlite3HashFind(&pDb->pSchema->aFKey, pF1->zTo, nTo);
-      if( pF2==pF1 ){
-        sqlite3HashInsert(&pDb->pSchema->aFKey, pF1->zTo, nTo, pF1->pNextTo);
+/*
+** Analyze the ORDER BY clause in a compound SELECT statement.   Modify
+** each term of the ORDER BY clause is a constant integer between 1
+** and N where N is the number of columns in the compound SELECT.
+**
+** ORDER BY terms that are already an integer between 1 and N are
+** unmodified.  ORDER BY terms that are integers outside the range of
+** 1 through N generate an error.  ORDER BY terms that are expressions
+** are matched against result set expressions of compound SELECT
+** beginning with the left-most SELECT and working toward the right.
+** At the first match, the ORDER BY expression is transformed into
+** the integer column number.
+**
+** Return the number of errors seen.
+*/
+static int resolveCompoundOrderBy(
+  Parse *pParse,        /* Parsing context.  Leave error messages here */
+  Select *pSelect       /* The SELECT statement containing the ORDER BY */
+){
+  int i;
+  ExprList *pOrderBy;
+  ExprList *pEList;
+  sqlite3 *db;
+  int moreToDo = 1;
+
+  pOrderBy = pSelect->pOrderBy;
+  if( pOrderBy==0 ) return 0;
+  db = pParse->db;
+#if SQLITE_MAX_COLUMN
+  if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
+    sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause");
+    return 1;
+  }
+#endif
+  for(i=0; i<pOrderBy->nExpr; i++){
+    pOrderBy->a[i].done = 0;
+  }
+  pSelect->pNext = 0;
+  while( pSelect->pPrior ){
+    pSelect->pPrior->pNext = pSelect;
+    pSelect = pSelect->pPrior;
+  }
+  while( pSelect && moreToDo ){
+    struct ExprList_item *pItem;
+    moreToDo = 0;
+    pEList = pSelect->pEList;
+    assert( pEList!=0 );
+    for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
+      int iCol = -1;
+      Expr *pE, *pDup;
+      if( pItem->done ) continue;
+      pE = pItem->pExpr;
+      if( sqlite3ExprIsInteger(pE, &iCol) ){
+        if( iCol<=0 || iCol>pEList->nExpr ){
+          resolveOutOfRangeError(pParse, "ORDER", i+1, pEList->nExpr);
+          return 1;
+        }
       }else{
-        while( pF2 && pF2->pNextTo!=pF1 ){ pF2=pF2->pNextTo; }
-        if( pF2 ){
-          pF2->pNextTo = pF1->pNextTo;
+        iCol = resolveAsName(pParse, pEList, pE);
+        if( iCol==0 ){
+          pDup = sqlite3ExprDup(db, pE, 0);
+          if( !db->mallocFailed ){
+            assert(pDup);
+            iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup);
+          }
+          sqlite3ExprDelete(db, pDup);
         }
       }
+      if( iCol>0 ){
+        CollSeq *pColl = pE->pColl;
+        int flags = pE->flags & EP_ExpCollate;
+        sqlite3ExprDelete(db, pE);
+        pItem->pExpr = pE = sqlite3Expr(db, TK_INTEGER, 0);
+        if( pE==0 ) return 1;
+        pE->pColl = pColl;
+        pE->flags |= EP_IntValue | flags;
+        pE->u.iValue = iCol;
+        pItem->iCol = (u16)iCol;
+        pItem->done = 1;
+      }else{
+        moreToDo = 1;
+      }
     }
-#endif
-    sqlite3DeleteTable(p);
+    pSelect = pSelect->pNext;
   }
-  db->flags |= SQLITE_InternChanges;
-}
-
-/*
-** Given a token, return a string that consists of the text of that
-** token with any quotations removed.  Space to hold the returned string
-** is obtained from sqliteMalloc() and must be freed by the calling
-** function.
-**
-** Tokens are often just pointers into the original SQL text and so
-** are not \000 terminated and are not persistent.  The returned string
-** is \000 terminated and is persistent.
-*/
-SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3 *db, Token *pName){
-  char *zName;
-  if( pName ){
-    zName = sqlite3DbStrNDup(db, (char*)pName->z, pName->n);
-    sqlite3Dequote(zName);
-  }else{
-    zName = 0;
+  for(i=0; i<pOrderBy->nExpr; i++){
+    if( pOrderBy->a[i].done==0 ){
+      sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any "
+            "column in the result set", i+1);
+      return 1;
+    }
   }
-  return zName;
-}
-
-/*
-** Open the sqlite_master table stored in database number iDb for
-** writing. The table is opened using cursor 0.
-*/
-SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *p, int iDb){
-  Vdbe *v = sqlite3GetVdbe(p);
-  sqlite3TableLock(p, iDb, MASTER_ROOT, 1, SCHEMA_TABLE(iDb));
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 5);/* sqlite_master has 5 columns */
-  sqlite3VdbeAddOp3(v, OP_OpenWrite, 0, MASTER_ROOT, iDb);
+  return 0;
 }
 
 /*
-** The token *pName contains the name of a database (either "main" or
-** "temp" or the name of an attached db). This routine returns the
-** index of the named database in db->aDb[], or -1 if the named db 
-** does not exist.
+** Check every term in the ORDER BY or GROUP BY clause pOrderBy of
+** the SELECT statement pSelect.  If any term is reference to a
+** result set expression (as determined by the ExprList.a.iCol field)
+** then convert that term into a copy of the corresponding result set
+** column.
+**
+** If any errors are detected, add an error message to pParse and
+** return non-zero.  Return zero if no errors are seen.
 */
-SQLITE_PRIVATE int sqlite3FindDb(sqlite3 *db, Token *pName){
-  int i = -1;    /* Database number */
-  int n;         /* Number of characters in the name */
-  Db *pDb;       /* A database whose name space is being searched */
-  char *zName;   /* Name we are searching for */
+SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(
+  Parse *pParse,        /* Parsing context.  Leave error messages here */
+  Select *pSelect,      /* The SELECT statement containing the clause */
+  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */
+  const char *zType     /* "ORDER" or "GROUP" */
+){
+  int i;
+  sqlite3 *db = pParse->db;
+  ExprList *pEList;
+  struct ExprList_item *pItem;
 
-  zName = sqlite3NameFromToken(db, pName);
-  if( zName ){
-    n = strlen(zName);
-    for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
-      if( (!OMIT_TEMPDB || i!=1 ) && n==strlen(pDb->zName) && 
-          0==sqlite3StrICmp(pDb->zName, zName) ){
-        break;
+  if( pOrderBy==0 || pParse->db->mallocFailed ) return 0;
+#if SQLITE_MAX_COLUMN
+  if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
+    sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType);
+    return 1;
+  }
+#endif
+  pEList = pSelect->pEList;
+  assert( pEList!=0 );  /* sqlite3SelectNew() guarantees this */
+  for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
+    if( pItem->iCol ){
+      if( pItem->iCol>pEList->nExpr ){
+        resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr);
+        return 1;
       }
+      resolveAlias(pParse, pEList, pItem->iCol-1, pItem->pExpr, zType);
     }
-    sqlite3_free(zName);
   }
-  return i;
+  return 0;
 }
 
-/* The table or view or trigger name is passed to this routine via tokens
-** pName1 and pName2. If the table name was fully qualified, for example:
-**
-** CREATE TABLE xxx.yyy (...);
-** 
-** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
-** the table name is not fully qualified, i.e.:
-**
-** CREATE TABLE yyy(...);
+/*
+** pOrderBy is an ORDER BY or GROUP BY clause in SELECT statement pSelect.
+** The Name context of the SELECT statement is pNC.  zType is either
+** "ORDER" or "GROUP" depending on which type of clause pOrderBy is.
 **
-** Then pName1 is set to "yyy" and pName2 is "".
+** This routine resolves each term of the clause into an expression.
+** If the order-by term is an integer I between 1 and N (where N is the
+** number of columns in the result set of the SELECT) then the expression
+** in the resolution is a copy of the I-th result-set expression.  If
+** the order-by term is an identify that corresponds to the AS-name of
+** a result-set expression, then the term resolves to a copy of the
+** result-set expression.  Otherwise, the expression is resolved in
+** the usual way - using sqlite3ResolveExprNames().
 **
-** This routine sets the *ppUnqual pointer to point at the token (pName1 or
-** pName2) that stores the unqualified table name.  The index of the
-** database "xxx" is returned.
+** This routine returns the number of errors.  If errors occur, then
+** an appropriate error message might be left in pParse.  (OOM errors
+** excepted.)
 */
-SQLITE_PRIVATE int sqlite3TwoPartName(
-  Parse *pParse,      /* Parsing and code generating context */
-  Token *pName1,      /* The "xxx" in the name "xxx.yyy" or "xxx" */
-  Token *pName2,      /* The "yyy" in the name "xxx.yyy" */
-  Token **pUnqual     /* Write the unqualified object name here */
+static int resolveOrderGroupBy(
+  NameContext *pNC,     /* The name context of the SELECT statement */
+  Select *pSelect,      /* The SELECT statement holding pOrderBy */
+  ExprList *pOrderBy,   /* An ORDER BY or GROUP BY clause to resolve */
+  const char *zType     /* Either "ORDER" or "GROUP", as appropriate */
 ){
-  int iDb;                    /* Database holding the object */
-  sqlite3 *db = pParse->db;
+  int i;                         /* Loop counter */
+  int iCol;                      /* Column number */
+  struct ExprList_item *pItem;   /* A term of the ORDER BY clause */
+  Parse *pParse;                 /* Parsing context */
+  int nResult;                   /* Number of terms in the result set */
 
-  if( pName2 && pName2->n>0 ){
-    assert( !db->init.busy );
-    *pUnqual = pName2;
-    iDb = sqlite3FindDb(db, pName1);
-    if( iDb<0 ){
-      sqlite3ErrorMsg(pParse, "unknown database %T", pName1);
-      pParse->nErr++;
-      return -1;
+  if( pOrderBy==0 ) return 0;
+  nResult = pSelect->pEList->nExpr;
+  pParse = pNC->pParse;
+  for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
+    Expr *pE = pItem->pExpr;
+    iCol = resolveAsName(pParse, pSelect->pEList, pE);
+    if( iCol>0 ){
+      /* If an AS-name match is found, mark this ORDER BY column as being
+      ** a copy of the iCol-th result-set column.  The subsequent call to
+      ** sqlite3ResolveOrderGroupBy() will convert the expression to a
+      ** copy of the iCol-th result-set expression. */
+      pItem->iCol = (u16)iCol;
+      continue;
+    }
+    if( sqlite3ExprIsInteger(pE, &iCol) ){
+      /* The ORDER BY term is an integer constant.  Again, set the column
+      ** number so that sqlite3ResolveOrderGroupBy() will convert the
+      ** order-by term to a copy of the result-set expression */
+      if( iCol<1 ){
+        resolveOutOfRangeError(pParse, zType, i+1, nResult);
+        return 1;
+      }
+      pItem->iCol = (u16)iCol;
+      continue;
     }
-  }else{
-    assert( db->init.iDb==0 || db->init.busy );
-    iDb = db->init.iDb;
-    *pUnqual = pName1;
-  }
-  return iDb;
-}
 
-/*
-** This routine is used to check if the UTF-8 string zName is a legal
-** unqualified name for a new schema object (table, index, view or
-** trigger). All names are legal except those that begin with the string
-** "sqlite_" (in upper, lower or mixed case). This portion of the namespace
-** is reserved for internal use.
-*/
-SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *pParse, const char *zName){
-  if( !pParse->db->init.busy && pParse->nested==0 
-          && (pParse->db->flags & SQLITE_WriteSchema)==0
-          && 0==sqlite3StrNICmp(zName, "sqlite_", 7) ){
-    sqlite3ErrorMsg(pParse, "object name reserved for internal use: %s", zName);
-    return SQLITE_ERROR;
+    /* Otherwise, treat the ORDER BY term as an ordinary expression */
+    pItem->iCol = 0;
+    if( sqlite3ResolveExprNames(pNC, pE) ){
+      return 1;
+    }
   }
-  return SQLITE_OK;
+  return sqlite3ResolveOrderGroupBy(pParse, pSelect, pOrderBy, zType);
 }
 
 /*
-** Begin constructing a new table representation in memory.  This is
-** the first of several action routines that get called in response
-** to a CREATE TABLE statement.  In particular, this routine is called
-** after seeing tokens "CREATE" and "TABLE" and the table name. The isTemp
-** flag is true if the table should be stored in the auxiliary database
-** file instead of in the main database file.  This is normally the case
-** when the "TEMP" or "TEMPORARY" keyword occurs in between
-** CREATE and TABLE.
-**
-** The new table record is initialized and put in pParse->pNewTable.
-** As more of the CREATE TABLE statement is parsed, additional action
-** routines will be called to add more information to this record.
-** At the end of the CREATE TABLE statement, the sqlite3EndTable() routine
-** is called to complete the construction of the new table record.
+** Resolve names in the SELECT statement p and all of its descendents.
 */
-SQLITE_PRIVATE void sqlite3StartTable(
-  Parse *pParse,   /* Parser context */
-  Token *pName1,   /* First part of the name of the table or view */
-  Token *pName2,   /* Second part of the name of the table or view */
-  int isTemp,      /* True if this is a TEMP table */
-  int isView,      /* True if this is a VIEW */
-  int isVirtual,   /* True if this is a VIRTUAL table */
-  int noErr        /* Do nothing if table already exists */
-){
-  Table *pTable;
-  char *zName = 0; /* The name of the new table */
-  sqlite3 *db = pParse->db;
-  Vdbe *v;
-  int iDb;         /* Database number to create the table in */
-  Token *pName;    /* Unqualified name of the table to create */
+static int resolveSelectStep(Walker *pWalker, Select *p){
+  NameContext *pOuterNC;  /* Context that contains this SELECT */
+  NameContext sNC;        /* Name context of this SELECT */
+  int isCompound;         /* True if p is a compound select */
+  int nCompound;          /* Number of compound terms processed so far */
+  Parse *pParse;          /* Parsing context */
+  ExprList *pEList;       /* Result set expression list */
+  int i;                  /* Loop counter */
+  ExprList *pGroupBy;     /* The GROUP BY clause */
+  Select *pLeftmost;      /* Left-most of SELECT of a compound */
+  sqlite3 *db;            /* Database connection */
+  
 
-  /* The table or view name to create is passed to this routine via tokens
-  ** pName1 and pName2. If the table name was fully qualified, for example:
-  **
-  ** CREATE TABLE xxx.yyy (...);
-  ** 
-  ** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
-  ** the table name is not fully qualified, i.e.:
-  **
-  ** CREATE TABLE yyy(...);
-  **
-  ** Then pName1 is set to "yyy" and pName2 is "".
-  **
-  ** The call below sets the pName pointer to point at the token (pName1 or
-  ** pName2) that stores the unqualified table name. The variable iDb is
-  ** set to the index of the database that the table or view is to be
-  ** created in.
-  */
-  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
-  if( iDb<0 ) return;
-  if( !OMIT_TEMPDB && isTemp && iDb>1 ){
-    /* If creating a temp table, the name may not be qualified */
-    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
-    return;
+  assert( p!=0 );
+  if( p->selFlags & SF_Resolved ){
+    return WRC_Prune;
   }
-  if( !OMIT_TEMPDB && isTemp ) iDb = 1;
+  pOuterNC = pWalker->u.pNC;
+  pParse = pWalker->pParse;
+  db = pParse->db;
 
-  pParse->sNameToken = *pName;
-  zName = sqlite3NameFromToken(db, pName);
-  if( zName==0 ) return;
-  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
-    goto begin_table_error;
+  /* Normally sqlite3SelectExpand() will be called first and will have
+  ** already expanded this SELECT.  However, if this is a subquery within
+  ** an expression, sqlite3ResolveExprNames() will be called without a
+  ** prior call to sqlite3SelectExpand().  When that happens, let
+  ** sqlite3SelectPrep() do all of the processing for this SELECT.
+  ** sqlite3SelectPrep() will invoke both sqlite3SelectExpand() and
+  ** this routine in the correct order.
+  */
+  if( (p->selFlags & SF_Expanded)==0 ){
+    sqlite3SelectPrep(pParse, p, pOuterNC);
+    return (pParse->nErr || db->mallocFailed) ? WRC_Abort : WRC_Prune;
   }
-  if( db->init.iDb==1 ) isTemp = 1;
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  assert( (isTemp & 1)==isTemp );
-  {
-    int code;
-    char *zDb = db->aDb[iDb].zName;
-    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(isTemp), 0, zDb) ){
-      goto begin_table_error;
+
+  isCompound = p->pPrior!=0;
+  nCompound = 0;
+  pLeftmost = p;
+  while( p ){
+    assert( (p->selFlags & SF_Expanded)!=0 );
+    assert( (p->selFlags & SF_Resolved)==0 );
+    p->selFlags |= SF_Resolved;
+
+    /* Resolve the expressions in the LIMIT and OFFSET clauses. These
+    ** are not allowed to refer to any names, so pass an empty NameContext.
+    */
+    memset(&sNC, 0, sizeof(sNC));
+    sNC.pParse = pParse;
+    if( sqlite3ResolveExprNames(&sNC, p->pLimit) ||
+        sqlite3ResolveExprNames(&sNC, p->pOffset) ){
+      return WRC_Abort;
     }
-    if( isView ){
-      if( !OMIT_TEMPDB && isTemp ){
-        code = SQLITE_CREATE_TEMP_VIEW;
-      }else{
-        code = SQLITE_CREATE_VIEW;
-      }
-    }else{
-      if( !OMIT_TEMPDB && isTemp ){
-        code = SQLITE_CREATE_TEMP_TABLE;
-      }else{
-        code = SQLITE_CREATE_TABLE;
+  
+    /* Set up the local name-context to pass to sqlite3ResolveExprNames() to
+    ** resolve the result-set expression list.
+    */
+    sNC.allowAgg = 1;
+    sNC.pSrcList = p->pSrc;
+    sNC.pNext = pOuterNC;
+  
+    /* Resolve names in the result set. */
+    pEList = p->pEList;
+    assert( pEList!=0 );
+    for(i=0; i<pEList->nExpr; i++){
+      Expr *pX = pEList->a[i].pExpr;
+      if( sqlite3ResolveExprNames(&sNC, pX) ){
+        return WRC_Abort;
       }
     }
-    if( !isVirtual && sqlite3AuthCheck(pParse, code, zName, 0, zDb) ){
-      goto begin_table_error;
+  
+    /* Recursively resolve names in all subqueries
+    */
+    for(i=0; i<p->pSrc->nSrc; i++){
+      struct SrcList_item *pItem = &p->pSrc->a[i];
+      if( pItem->pSelect ){
+        const char *zSavedContext = pParse->zAuthContext;
+        if( pItem->zName ) pParse->zAuthContext = pItem->zName;
+        sqlite3ResolveSelectNames(pParse, pItem->pSelect, pOuterNC);
+        pParse->zAuthContext = zSavedContext;
+        if( pParse->nErr || db->mallocFailed ) return WRC_Abort;
+      }
     }
-  }
-#endif
-
-  /* Make sure the new table name does not collide with an existing
-  ** index or table name in the same database.  Issue an error message if
-  ** it does. The exception is if the statement being parsed was passed
-  ** to an sqlite3_declare_vtab() call. In that case only the column names
-  ** and types will be used, so there is no need to test for namespace
-  ** collisions.
-  */
-  if( !IN_DECLARE_VTAB ){
-    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-      goto begin_table_error;
+  
+    /* If there are no aggregate functions in the result-set, and no GROUP BY 
+    ** expression, do not allow aggregates in any of the other expressions.
+    */
+    assert( (p->selFlags & SF_Aggregate)==0 );
+    pGroupBy = p->pGroupBy;
+    if( pGroupBy || sNC.hasAgg ){
+      p->selFlags |= SF_Aggregate;
+    }else{
+      sNC.allowAgg = 0;
     }
-    pTable = sqlite3FindTable(db, zName, db->aDb[iDb].zName);
-    if( pTable ){
-      if( !noErr ){
-        sqlite3ErrorMsg(pParse, "table %T already exists", pName);
-      }
-      goto begin_table_error;
+  
+    /* If a HAVING clause is present, then there must be a GROUP BY clause.
+    */
+    if( p->pHaving && !pGroupBy ){
+      sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
+      return WRC_Abort;
     }
-    if( sqlite3FindIndex(db, zName, 0)!=0 && (iDb==0 || !db->init.busy) ){
-      sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
-      goto begin_table_error;
+  
+    /* Add the expression list to the name-context before parsing the
+    ** other expressions in the SELECT statement. This is so that
+    ** expressions in the WHERE clause (etc.) can refer to expressions by
+    ** aliases in the result set.
+    **
+    ** Minor point: If this is the case, then the expression will be
+    ** re-evaluated for each reference to it.
+    */
+    sNC.pEList = p->pEList;
+    if( sqlite3ResolveExprNames(&sNC, p->pWhere) ||
+       sqlite3ResolveExprNames(&sNC, p->pHaving)
+    ){
+      return WRC_Abort;
     }
-  }
-
-  pTable = sqlite3DbMallocZero(db, sizeof(Table));
-  if( pTable==0 ){
-    db->mallocFailed = 1;
-    pParse->rc = SQLITE_NOMEM;
-    pParse->nErr++;
-    goto begin_table_error;
-  }
-  pTable->zName = zName;
-  pTable->iPKey = -1;
-  pTable->pSchema = db->aDb[iDb].pSchema;
-  pTable->nRef = 1;
-  if( pParse->pNewTable ) sqlite3DeleteTable(pParse->pNewTable);
-  pParse->pNewTable = pTable;
-
-  /* If this is the magic sqlite_sequence table used by autoincrement,
-  ** then record a pointer to this table in the main database structure
-  ** so that INSERT can find the table easily.
-  */
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-  if( !pParse->nested && strcmp(zName, "sqlite_sequence")==0 ){
-    pTable->pSchema->pSeqTab = pTable;
-  }
-#endif
 
-  /* Begin generating the code that will insert the table record into
-  ** the SQLITE_MASTER table.  Note in particular that we must go ahead
-  ** and allocate the record number for the table entry now.  Before any
-  ** PRIMARY KEY or UNIQUE keywords are parsed.  Those keywords will cause
-  ** indices to be created and the table record must come before the 
-  ** indices.  Hence, the record number for the table must be allocated
-  ** now.
-  */
-  if( !db->init.busy && (v = sqlite3GetVdbe(pParse))!=0 ){
-    int j1;
-    int fileFormat;
-    int reg1, reg2, reg3;
-    sqlite3BeginWriteOperation(pParse, 0, iDb);
+    /* The ORDER BY and GROUP BY clauses may not refer to terms in
+    ** outer queries 
+    */
+    sNC.pNext = 0;
+    sNC.allowAgg = 1;
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( isVirtual ){
-      sqlite3VdbeAddOp0(v, OP_VBegin);
+    /* Process the ORDER BY clause for singleton SELECT statements.
+    ** The ORDER BY clause for compounds SELECT statements is handled
+    ** below, after all of the result-sets for all of the elements of
+    ** the compound have been resolved.
+    */
+    if( !isCompound && resolveOrderGroupBy(&sNC, p, p->pOrderBy, "ORDER") ){
+      return WRC_Abort;
     }
-#endif
-
-    /* If the file format and encoding in the database have not been set, 
-    ** set them now.
+    if( db->mallocFailed ){
+      return WRC_Abort;
+    }
+  
+    /* Resolve the GROUP BY clause.  At the same time, make sure 
+    ** the GROUP BY clause does not contain aggregate functions.
     */
-    reg1 = pParse->regRowid = ++pParse->nMem;
-    reg2 = pParse->regRoot = ++pParse->nMem;
-    reg3 = ++pParse->nMem;
-    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, reg3, 1);   /* file_format */
-    sqlite3VdbeUsesBtree(v, iDb);
-    j1 = sqlite3VdbeAddOp1(v, OP_If, reg3);
-    fileFormat = (db->flags & SQLITE_LegacyFileFmt)!=0 ?
-                  1 : SQLITE_MAX_FILE_FORMAT;
-    sqlite3VdbeAddOp2(v, OP_Integer, fileFormat, reg3);
-    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 1, reg3);
-    sqlite3VdbeAddOp2(v, OP_Integer, ENC(db), reg3);
-    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 4, reg3);
-    sqlite3VdbeJumpHere(v, j1);
+    if( pGroupBy ){
+      struct ExprList_item *pItem;
+    
+      if( resolveOrderGroupBy(&sNC, p, pGroupBy, "GROUP") || db->mallocFailed ){
+        return WRC_Abort;
+      }
+      for(i=0, pItem=pGroupBy->a; i<pGroupBy->nExpr; i++, pItem++){
+        if( ExprHasProperty(pItem->pExpr, EP_Agg) ){
+          sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
+              "the GROUP BY clause");
+          return WRC_Abort;
+        }
+      }
+    }
 
-    /* This just creates a place-holder record in the sqlite_master table.
-    ** The record created does not contain anything yet.  It will be replaced
-    ** by the real entry in code generated at sqlite3EndTable().
-    **
-    ** The rowid for the new entry is left on the top of the stack.
-    ** The rowid value is needed by the code that sqlite3EndTable will
-    ** generate.
+    /* Advance to the next term of the compound
     */
-#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
-    if( isView || isVirtual ){
-      sqlite3VdbeAddOp2(v, OP_Integer, 0, reg2);
-    }else
-#endif
-    {
-      sqlite3VdbeAddOp2(v, OP_CreateTable, iDb, reg2);
-    }
-    sqlite3OpenMasterTable(pParse, iDb);
-    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, reg1);
-    sqlite3VdbeAddOp2(v, OP_Null, 0, reg3);
-    sqlite3VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
-    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
-    sqlite3VdbeAddOp0(v, OP_Close);
+    p = p->pPrior;
+    nCompound++;
   }
 
-  /* Normal (non-error) return. */
-  return;
+  /* Resolve the ORDER BY on a compound SELECT after all terms of
+  ** the compound have been resolved.
+  */
+  if( isCompound && resolveCompoundOrderBy(pParse, pLeftmost) ){
+    return WRC_Abort;
+  }
 
-  /* If an error occurs, we jump here */
-begin_table_error:
-  sqlite3_free(zName);
-  return;
+  return WRC_Prune;
 }
 
 /*
-** This macro is used to compare two strings in a case-insensitive manner.
-** It is slightly faster than calling sqlite3StrICmp() directly, but
-** produces larger code.
+** This routine walks an expression tree and resolves references to
+** table columns and result-set columns.  At the same time, do error
+** checking on function usage and set a flag if any aggregate functions
+** are seen.
 **
-** WARNING: This macro is not compatible with the strcmp() family. It
-** returns true if the two strings are equal, otherwise false.
-*/
-#define STRICMP(x, y) (\
-sqlite3UpperToLower[*(unsigned char *)(x)]==   \
-sqlite3UpperToLower[*(unsigned char *)(y)]     \
-&& sqlite3StrICmp((x)+1,(y)+1)==0 )
-
-/*
-** Add a new column to the table currently being constructed.
+** To resolve table columns references we look for nodes (or subtrees) of the 
+** form X.Y.Z or Y.Z or just Z where
 **
-** The parser calls this routine once for each column declaration
-** in a CREATE TABLE statement.  sqlite3StartTable() gets called
-** first to get things going.  Then this routine is called for each
-** column.
+**      X:   The name of a database.  Ex:  "main" or "temp" or
+**           the symbolic name assigned to an ATTACH-ed database.
+**
+**      Y:   The name of a table in a FROM clause.  Or in a trigger
+**           one of the special names "old" or "new".
+**
+**      Z:   The name of a column in table Y.
+**
+** The node at the root of the subtree is modified as follows:
+**
+**    Expr.op        Changed to TK_COLUMN
+**    Expr.pTab      Points to the Table object for X.Y
+**    Expr.iColumn   The column index in X.Y.  -1 for the rowid.
+**    Expr.iTable    The VDBE cursor number for X.Y
+**
+**
+** To resolve result-set references, look for expression nodes of the
+** form Z (with no X and Y prefix) where the Z matches the right-hand
+** size of an AS clause in the result-set of a SELECT.  The Z expression
+** is replaced by a copy of the left-hand side of the result-set expression.
+** Table-name and function resolution occurs on the substituted expression
+** tree.  For example, in:
+**
+**      SELECT a+b AS x, c+d AS y FROM t1 ORDER BY x;
+**
+** The "x" term of the order by is replaced by "a+b" to render:
+**
+**      SELECT a+b AS x, c+d AS y FROM t1 ORDER BY a+b;
+**
+** Function calls are checked to make sure that the function is 
+** defined and that the correct number of arguments are specified.
+** If the function is an aggregate function, then the pNC->hasAgg is
+** set and the opcode is changed from TK_FUNCTION to TK_AGG_FUNCTION.
+** If an expression contains aggregate functions then the EP_Agg
+** property on the expression is set.
+**
+** An error message is left in pParse if anything is amiss.  The number
+** if errors is returned.
 */
-SQLITE_PRIVATE void sqlite3AddColumn(Parse *pParse, Token *pName){
-  Table *p;
-  int i;
-  char *z;
-  Column *pCol;
-  sqlite3 *db = pParse->db;
-  if( (p = pParse->pNewTable)==0 ) return;
-#if SQLITE_MAX_COLUMN
-  if( p->nCol+1>db->aLimit[SQLITE_LIMIT_COLUMN] ){
-    sqlite3ErrorMsg(pParse, "too many columns on %s", p->zName);
-    return;
+SQLITE_PRIVATE int sqlite3ResolveExprNames( 
+  NameContext *pNC,       /* Namespace to resolve expressions in. */
+  Expr *pExpr             /* The expression to be analyzed. */
+){
+  int savedHasAgg;
+  Walker w;
+
+  if( pExpr==0 ) return 0;
+#if SQLITE_MAX_EXPR_DEPTH>0
+  {
+    Parse *pParse = pNC->pParse;
+    if( sqlite3ExprCheckHeight(pParse, pExpr->nHeight+pNC->pParse->nHeight) ){
+      return 1;
+    }
+    pParse->nHeight += pExpr->nHeight;
   }
 #endif
-  z = sqlite3NameFromToken(pParse->db, pName);
-  if( z==0 ) return;
-  for(i=0; i<p->nCol; i++){
-    if( STRICMP(z, p->aCol[i].zName) ){
-      sqlite3ErrorMsg(pParse, "duplicate column name: %s", z);
-      sqlite3_free(z);
-      return;
-    }
+  savedHasAgg = pNC->hasAgg;
+  pNC->hasAgg = 0;
+  w.xExprCallback = resolveExprStep;
+  w.xSelectCallback = resolveSelectStep;
+  w.pParse = pNC->pParse;
+  w.u.pNC = pNC;
+  sqlite3WalkExpr(&w, pExpr);
+#if SQLITE_MAX_EXPR_DEPTH>0
+  pNC->pParse->nHeight -= pExpr->nHeight;
+#endif
+  if( pNC->nErr>0 || w.pParse->nErr>0 ){
+    ExprSetProperty(pExpr, EP_Error);
   }
-  if( (p->nCol & 0x7)==0 ){
-    Column *aNew;
-    aNew = sqlite3DbRealloc(pParse->db,p->aCol,(p->nCol+8)*sizeof(p->aCol[0]));
-    if( aNew==0 ){
-      sqlite3_free(z);
-      return;
-    }
-    p->aCol = aNew;
+  if( pNC->hasAgg ){
+    ExprSetProperty(pExpr, EP_Agg);
+  }else if( savedHasAgg ){
+    pNC->hasAgg = 1;
   }
-  pCol = &p->aCol[p->nCol];
-  memset(pCol, 0, sizeof(p->aCol[0]));
-  pCol->zName = z;
- 
-  /* If there is no type specified, columns have the default affinity
-  ** 'NONE'. If there is a type specified, then sqlite3AddColumnType() will
-  ** be called next to set pCol->affinity correctly.
-  */
-  pCol->affinity = SQLITE_AFF_NONE;
-  p->nCol++;
+  return ExprHasProperty(pExpr, EP_Error);
 }
 
+
 /*
-** This routine is called by the parser while in the middle of
-** parsing a CREATE TABLE statement.  A "NOT NULL" constraint has
-** been seen on a column.  This routine sets the notNull flag on
-** the column currently under construction.
+** Resolve all names in all expressions of a SELECT and in all
+** decendents of the SELECT, including compounds off of p->pPrior,
+** subqueries in expressions, and subqueries used as FROM clause
+** terms.
+**
+** See sqlite3ResolveExprNames() for a description of the kinds of
+** transformations that occur.
+**
+** All SELECT statements should have been expanded using
+** sqlite3SelectExpand() prior to invoking this routine.
 */
-SQLITE_PRIVATE void sqlite3AddNotNull(Parse *pParse, int onError){
-  Table *p;
-  int i;
-  if( (p = pParse->pNewTable)==0 ) return;
-  i = p->nCol-1;
-  if( i>=0 ) p->aCol[i].notNull = onError;
+SQLITE_PRIVATE void sqlite3ResolveSelectNames(
+  Parse *pParse,         /* The parser context */
+  Select *p,             /* The SELECT statement being coded. */
+  NameContext *pOuterNC  /* Name context for parent SELECT statement */
+){
+  Walker w;
+
+  assert( p!=0 );
+  w.xExprCallback = resolveExprStep;
+  w.xSelectCallback = resolveSelectStep;
+  w.pParse = pParse;
+  w.u.pNC = pOuterNC;
+  sqlite3WalkSelect(&w, p);
 }
 
+/************** End of resolve.c *********************************************/
+/************** Begin file expr.c ********************************************/
 /*
-** Scan the column type name zType (length nType) and return the
-** associated affinity type.
+** 2001 September 15
 **
-** This routine does a case-independent search of zType for the 
-** substrings in the following table. If one of the substrings is
-** found, the corresponding affinity is returned. If zType contains
-** more than one of the substrings, entries toward the top of 
-** the table take priority. For example, if zType is 'BLOBINT', 
-** SQLITE_AFF_INTEGER is returned.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** Substring     | Affinity
-** --------------------------------
-** 'INT'         | SQLITE_AFF_INTEGER
-** 'CHAR'        | SQLITE_AFF_TEXT
-** 'CLOB'        | SQLITE_AFF_TEXT
-** 'TEXT'        | SQLITE_AFF_TEXT
-** 'BLOB'        | SQLITE_AFF_NONE
-** 'REAL'        | SQLITE_AFF_REAL
-** 'FLOA'        | SQLITE_AFF_REAL
-** 'DOUB'        | SQLITE_AFF_REAL
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** If none of the substrings in the above table are found,
-** SQLITE_AFF_NUMERIC is returned.
+*************************************************************************
+** This file contains routines used for analyzing expressions and
+** for generating VDBE code that evaluates expressions in SQLite.
 */
-SQLITE_PRIVATE char sqlite3AffinityType(const Token *pType){
-  u32 h = 0;
-  char aff = SQLITE_AFF_NUMERIC;
-  const unsigned char *zIn = pType->z;
-  const unsigned char *zEnd = &pType->z[pType->n];
 
-  while( zIn!=zEnd ){
-    h = (h<<8) + sqlite3UpperToLower[*zIn];
-    zIn++;
-    if( h==(('c'<<24)+('h'<<16)+('a'<<8)+'r') ){             /* CHAR */
-      aff = SQLITE_AFF_TEXT; 
-    }else if( h==(('c'<<24)+('l'<<16)+('o'<<8)+'b') ){       /* CLOB */
-      aff = SQLITE_AFF_TEXT;
-    }else if( h==(('t'<<24)+('e'<<16)+('x'<<8)+'t') ){       /* TEXT */
-      aff = SQLITE_AFF_TEXT;
-    }else if( h==(('b'<<24)+('l'<<16)+('o'<<8)+'b')          /* BLOB */
-        && (aff==SQLITE_AFF_NUMERIC || aff==SQLITE_AFF_REAL) ){
-      aff = SQLITE_AFF_NONE;
-#ifndef SQLITE_OMIT_FLOATING_POINT
-    }else if( h==(('r'<<24)+('e'<<16)+('a'<<8)+'l')          /* REAL */
-        && aff==SQLITE_AFF_NUMERIC ){
-      aff = SQLITE_AFF_REAL;
-    }else if( h==(('f'<<24)+('l'<<16)+('o'<<8)+'a')          /* FLOA */
-        && aff==SQLITE_AFF_NUMERIC ){
-      aff = SQLITE_AFF_REAL;
-    }else if( h==(('d'<<24)+('o'<<16)+('u'<<8)+'b')          /* DOUB */
-        && aff==SQLITE_AFF_NUMERIC ){
-      aff = SQLITE_AFF_REAL;
+/*
+** Return the 'affinity' of the expression pExpr if any.
+**
+** If pExpr is a column, a reference to a column via an 'AS' alias,
+** or a sub-select with a column as the return value, then the 
+** affinity of that column is returned. Otherwise, 0x00 is returned,
+** indicating no affinity for the expression.
+**
+** i.e. the WHERE clause expresssions in the following statements all
+** have an affinity:
+**
+** CREATE TABLE t1(a);
+** SELECT * FROM t1 WHERE a;
+** SELECT a AS b FROM t1 WHERE b;
+** SELECT * FROM t1 WHERE (select a from t1);
+*/
+SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr){
+  int op = pExpr->op;
+  if( op==TK_SELECT ){
+    assert( pExpr->flags&EP_xIsSelect );
+    return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);
+  }
+#ifndef SQLITE_OMIT_CAST
+  if( op==TK_CAST ){
+    assert( !ExprHasProperty(pExpr, EP_IntValue) );
+    return sqlite3AffinityType(pExpr->u.zToken);
+  }
 #endif
-    }else if( (h&0x00FFFFFF)==(('i'<<16)+('n'<<8)+'t') ){    /* INT */
-      aff = SQLITE_AFF_INTEGER;
-      break;
-    }
+  if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER) 
+   && pExpr->pTab!=0
+  ){
+    /* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
+    ** a TK_COLUMN but was previously evaluated and cached in a register */
+    int j = pExpr->iColumn;
+    if( j<0 ) return SQLITE_AFF_INTEGER;
+    assert( pExpr->pTab && j<pExpr->pTab->nCol );
+    return pExpr->pTab->aCol[j].affinity;
   }
-
-  return aff;
+  return pExpr->affinity;
 }
 
 /*
-** This routine is called by the parser while in the middle of
-** parsing a CREATE TABLE statement.  The pFirst token is the first
-** token in the sequence of tokens that describe the type of the
-** column currently under construction.   pLast is the last token
-** in the sequence.  Use this information to construct a string
-** that contains the typename of the column and store that string
-** in zType.
-*/ 
-SQLITE_PRIVATE void sqlite3AddColumnType(Parse *pParse, Token *pType){
-  Table *p;
-  int i;
-  Column *pCol;
-
-  if( (p = pParse->pNewTable)==0 ) return;
-  i = p->nCol-1;
-  if( i<0 ) return;
-  pCol = &p->aCol[i];
-  sqlite3_free(pCol->zType);
-  pCol->zType = sqlite3NameFromToken(pParse->db, pType);
-  pCol->affinity = sqlite3AffinityType(pType);
+** Set the collating sequence for expression pExpr to be the collating
+** sequence named by pToken.   Return a pointer to the revised expression.
+** The collating sequence is marked as "explicit" using the EP_ExpCollate
+** flag.  An explicit collating sequence will override implicit
+** collating sequences.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
+  char *zColl = 0;            /* Dequoted name of collation sequence */
+  CollSeq *pColl;
+  sqlite3 *db = pParse->db;
+  zColl = sqlite3NameFromToken(db, pCollName);
+  if( pExpr && zColl ){
+    pColl = sqlite3LocateCollSeq(pParse, zColl);
+    if( pColl ){
+      pExpr->pColl = pColl;
+      pExpr->flags |= EP_ExpCollate;
+    }
+  }
+  sqlite3DbFree(db, zColl);
+  return pExpr;
 }
 
 /*
-** The expression is the default value for the most recently added column
-** of the table currently under construction.
-**
-** Default value expressions must be constant.  Raise an exception if this
-** is not the case.
-**
-** This routine is called by the parser while in the middle of
-** parsing a CREATE TABLE statement.
+** Return the default collation sequence for the expression pExpr. If
+** there is no default collation type, return 0.
 */
-SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse *pParse, Expr *pExpr){
-  Table *p;
-  Column *pCol;
-  if( (p = pParse->pNewTable)!=0 ){
-    pCol = &(p->aCol[p->nCol-1]);
-    if( !sqlite3ExprIsConstantOrFunction(pExpr) ){
-      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
-          pCol->zName);
-    }else{
-      Expr *pCopy;
-      sqlite3 *db = pParse->db;
-      sqlite3ExprDelete(pCol->pDflt);
-      pCol->pDflt = pCopy = sqlite3ExprDup(db, pExpr);
-      if( pCopy ){
-        sqlite3TokenCopy(db, &pCopy->span, &pExpr->span);
+SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
+  CollSeq *pColl = 0;
+  Expr *p = pExpr;
+  while( ALWAYS(p) ){
+    int op;
+    pColl = p->pColl;
+    if( pColl ) break;
+    op = p->op;
+    if( p->pTab!=0 && (
+        op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER || op==TK_TRIGGER
+    )){
+      /* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally
+      ** a TK_COLUMN but was previously evaluated and cached in a register */
+      const char *zColl;
+      int j = p->iColumn;
+      if( j>=0 ){
+        sqlite3 *db = pParse->db;
+        zColl = p->pTab->aCol[j].zColl;
+        pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
+        pExpr->pColl = pColl;
       }
+      break;
     }
+    if( op!=TK_CAST && op!=TK_UPLUS ){
+      break;
+    }
+    p = p->pLeft;
+  }
+  if( sqlite3CheckCollSeq(pParse, pColl) ){ 
+    pColl = 0;
   }
-  sqlite3ExprDelete(pExpr);
+  return pColl;
 }
 
 /*
-** Designate the PRIMARY KEY for the table.  pList is a list of names 
-** of columns that form the primary key.  If pList is NULL, then the
-** most recently added column of the table is the primary key.
-**
-** A table can have at most one primary key.  If the table already has
-** a primary key (and this is the second primary key) then create an
-** error.
-**
-** If the PRIMARY KEY is on a single column whose datatype is INTEGER,
-** then we will try to use that column as the rowid.  Set the Table.iPKey
-** field of the table under construction to be the index of the
-** INTEGER PRIMARY KEY column.  Table.iPKey is set to -1 if there is
-** no INTEGER PRIMARY KEY.
-**
-** If the key is not an INTEGER PRIMARY KEY, then create a unique
-** index for the key.  No index is created for INTEGER PRIMARY KEYs.
+** pExpr is an operand of a comparison operator.  aff2 is the
+** type affinity of the other operand.  This routine returns the
+** type affinity that should be used for the comparison operator.
 */
-SQLITE_PRIVATE void sqlite3AddPrimaryKey(
-  Parse *pParse,    /* Parsing context */
-  ExprList *pList,  /* List of field names to be indexed */
-  int onError,      /* What to do with a uniqueness conflict */
-  int autoInc,      /* True if the AUTOINCREMENT keyword is present */
-  int sortOrder     /* SQLITE_SO_ASC or SQLITE_SO_DESC */
-){
-  Table *pTab = pParse->pNewTable;
-  char *zType = 0;
-  int iCol = -1, i;
-  if( pTab==0 || IN_DECLARE_VTAB ) goto primary_key_exit;
-  if( pTab->hasPrimKey ){
-    sqlite3ErrorMsg(pParse, 
-      "table \"%s\" has more than one primary key", pTab->zName);
-    goto primary_key_exit;
-  }
-  pTab->hasPrimKey = 1;
-  if( pList==0 ){
-    iCol = pTab->nCol - 1;
-    pTab->aCol[iCol].isPrimKey = 1;
-  }else{
-    for(i=0; i<pList->nExpr; i++){
-      for(iCol=0; iCol<pTab->nCol; iCol++){
-        if( sqlite3StrICmp(pList->a[i].zName, pTab->aCol[iCol].zName)==0 ){
-          break;
-        }
-      }
-      if( iCol<pTab->nCol ){
-        pTab->aCol[iCol].isPrimKey = 1;
-      }
+SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2){
+  char aff1 = sqlite3ExprAffinity(pExpr);
+  if( aff1 && aff2 ){
+    /* Both sides of the comparison are columns. If one has numeric
+    ** affinity, use that. Otherwise use no affinity.
+    */
+    if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){
+      return SQLITE_AFF_NUMERIC;
+    }else{
+      return SQLITE_AFF_NONE;
     }
-    if( pList->nExpr>1 ) iCol = -1;
-  }
-  if( iCol>=0 && iCol<pTab->nCol ){
-    zType = pTab->aCol[iCol].zType;
-  }
-  if( zType && sqlite3StrICmp(zType, "INTEGER")==0
-        && sortOrder==SQLITE_SO_ASC ){
-    pTab->iPKey = iCol;
-    pTab->keyConf = onError;
-    pTab->autoInc = autoInc;
-  }else if( autoInc ){
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-    sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
-       "INTEGER PRIMARY KEY");
-#endif
+  }else if( !aff1 && !aff2 ){
+    /* Neither side of the comparison is a column.  Compare the
+    ** results directly.
+    */
+    return SQLITE_AFF_NONE;
   }else{
-    sqlite3CreateIndex(pParse, 0, 0, 0, pList, onError, 0, 0, sortOrder, 0);
-    pList = 0;
+    /* One side is a column, the other is not. Use the columns affinity. */
+    assert( aff1==0 || aff2==0 );
+    return (aff1 + aff2);
   }
-
-primary_key_exit:
-  sqlite3ExprListDelete(pList);
-  return;
 }
 
 /*
-** Add a new CHECK constraint to the table currently under construction.
+** pExpr is a comparison operator.  Return the type affinity that should
+** be applied to both operands prior to doing the comparison.
 */
-SQLITE_PRIVATE void sqlite3AddCheckConstraint(
-  Parse *pParse,    /* Parsing context */
-  Expr *pCheckExpr  /* The check expression */
-){
-#ifndef SQLITE_OMIT_CHECK
-  Table *pTab = pParse->pNewTable;
-  sqlite3 *db = pParse->db;
-  if( pTab && !IN_DECLARE_VTAB ){
-    /* The CHECK expression must be duplicated so that tokens refer
-    ** to malloced space and not the (ephemeral) text of the CREATE TABLE
-    ** statement */
-    pTab->pCheck = sqlite3ExprAnd(db, pTab->pCheck, 
-                                  sqlite3ExprDup(db, pCheckExpr));
+static char comparisonAffinity(Expr *pExpr){
+  char aff;
+  assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||
+          pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||
+          pExpr->op==TK_NE || pExpr->op==TK_IS || pExpr->op==TK_ISNOT );
+  assert( pExpr->pLeft );
+  aff = sqlite3ExprAffinity(pExpr->pLeft);
+  if( pExpr->pRight ){
+    aff = sqlite3CompareAffinity(pExpr->pRight, aff);
+  }else if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+    aff = sqlite3CompareAffinity(pExpr->x.pSelect->pEList->a[0].pExpr, aff);
+  }else if( !aff ){
+    aff = SQLITE_AFF_NONE;
   }
-#endif
-  sqlite3ExprDelete(pCheckExpr);
+  return aff;
 }
 
 /*
-** Set the collation function of the most recently parsed table column
-** to the CollSeq given.
+** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
+** idx_affinity is the affinity of an indexed column. Return true
+** if the index with affinity idx_affinity may be used to implement
+** the comparison in pExpr.
 */
-SQLITE_PRIVATE void sqlite3AddCollateType(Parse *pParse, Token *pToken){
-  Table *p;
-  int i;
-  char *zColl;              /* Dequoted name of collation sequence */
-
-  if( (p = pParse->pNewTable)==0 ) return;
-  i = p->nCol-1;
-
-  zColl = sqlite3NameFromToken(pParse->db, pToken);
-  if( !zColl ) return;
-
-  if( sqlite3LocateCollSeq(pParse, zColl, -1) ){
-    Index *pIdx;
-    p->aCol[i].zColl = zColl;
-  
-    /* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
-    ** then an index may have been created on this column before the
-    ** collation type was added. Correct this if it is the case.
-    */
-    for(pIdx=p->pIndex; pIdx; pIdx=pIdx->pNext){
-      assert( pIdx->nColumn==1 );
-      if( pIdx->aiColumn[0]==i ){
-        pIdx->azColl[0] = p->aCol[i].zColl;
-      }
-    }
-  }else{
-    sqlite3_free(zColl);
+SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){
+  char aff = comparisonAffinity(pExpr);
+  switch( aff ){
+    case SQLITE_AFF_NONE:
+      return 1;
+    case SQLITE_AFF_TEXT:
+      return idx_affinity==SQLITE_AFF_TEXT;
+    default:
+      return sqlite3IsNumericAffinity(idx_affinity);
   }
 }
 
 /*
-** This function returns the collation sequence for database native text
-** encoding identified by the string zName, length nName.
-**
-** If the requested collation sequence is not available, or not available
-** in the database native encoding, the collation factory is invoked to
-** request it. If the collation factory does not supply such a sequence,
-** and the sequence is available in another text encoding, then that is
-** returned instead.
+** Return the P5 value that should be used for a binary comparison
+** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
+*/
+static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){
+  u8 aff = (char)sqlite3ExprAffinity(pExpr2);
+  aff = (u8)sqlite3CompareAffinity(pExpr1, aff) | (u8)jumpIfNull;
+  return aff;
+}
+
+/*
+** Return a pointer to the collation sequence that should be used by
+** a binary comparison operator comparing pLeft and pRight.
 **
-** If no versions of the requested collations sequence are available, or
-** another error occurs, NULL is returned and an error message written into
-** pParse.
+** If the left hand expression has a collating sequence type, then it is
+** used. Otherwise the collation sequence for the right hand expression
+** is used, or the default (BINARY) if neither expression has a collating
+** type.
 **
-** This routine is a wrapper around sqlite3FindCollSeq().  This routine
-** invokes the collation factory if the named collation cannot be found
-** and generates an error message.
+** Argument pRight (but not pLeft) may be a null pointer. In this case,
+** it is not considered.
 */
-SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName){
-  sqlite3 *db = pParse->db;
-  u8 enc = ENC(db);
-  u8 initbusy = db->init.busy;
+SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(
+  Parse *pParse, 
+  Expr *pLeft, 
+  Expr *pRight
+){
   CollSeq *pColl;
-
-  pColl = sqlite3FindCollSeq(db, enc, zName, nName, initbusy);
-  if( !initbusy && (!pColl || !pColl->xCmp) ){
-    pColl = sqlite3GetCollSeq(db, pColl, zName, nName);
+  assert( pLeft );
+  if( pLeft->flags & EP_ExpCollate ){
+    assert( pLeft->pColl );
+    pColl = pLeft->pColl;
+  }else if( pRight && pRight->flags & EP_ExpCollate ){
+    assert( pRight->pColl );
+    pColl = pRight->pColl;
+  }else{
+    pColl = sqlite3ExprCollSeq(pParse, pLeft);
     if( !pColl ){
-      if( nName<0 ){
-        nName = strlen(zName);
-      }
-      sqlite3ErrorMsg(pParse, "no such collation sequence: %.*s", nName, zName);
-      pColl = 0;
+      pColl = sqlite3ExprCollSeq(pParse, pRight);
     }
   }
-
   return pColl;
 }
 
-
 /*
-** Generate code that will increment the schema cookie.
-**
-** The schema cookie is used to determine when the schema for the
-** database changes.  After each schema change, the cookie value
-** changes.  When a process first reads the schema it records the
-** cookie.  Thereafter, whenever it goes to access the database,
-** it checks the cookie to make sure the schema has not changed
-** since it was last read.
-**
-** This plan is not completely bullet-proof.  It is possible for
-** the schema to change multiple times and for the cookie to be
-** set back to prior value.  But schema changes are infrequent
-** and the probability of hitting the same cookie value is only
-** 1 chance in 2^32.  So we're safe enough.
+** Generate the operands for a comparison operation.  Before
+** generating the code for each operand, set the EP_AnyAff
+** flag on the expression so that it will be able to used a
+** cached column value that has previously undergone an
+** affinity change.
 */
-SQLITE_PRIVATE void sqlite3ChangeCookie(Parse *pParse, int iDb){
-  int r1 = sqlite3GetTempReg(pParse);
-  sqlite3 *db = pParse->db;
-  Vdbe *v = pParse->pVdbe;
-  sqlite3VdbeAddOp2(v, OP_Integer, db->aDb[iDb].pSchema->schema_cookie+1, r1);
-  sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 0, r1);
-  sqlite3ReleaseTempReg(pParse, r1);
+static void codeCompareOperands(
+  Parse *pParse,    /* Parsing and code generating context */
+  Expr *pLeft,      /* The left operand */
+  int *pRegLeft,    /* Register where left operand is stored */
+  int *pFreeLeft,   /* Free this register when done */
+  Expr *pRight,     /* The right operand */
+  int *pRegRight,   /* Register where right operand is stored */
+  int *pFreeRight   /* Write temp register for right operand there */
+){
+  while( pLeft->op==TK_UPLUS ) pLeft = pLeft->pLeft;
+  pLeft->flags |= EP_AnyAff;
+  *pRegLeft = sqlite3ExprCodeTemp(pParse, pLeft, pFreeLeft);
+  while( pRight->op==TK_UPLUS ) pRight = pRight->pLeft;
+  pRight->flags |= EP_AnyAff;
+  *pRegRight = sqlite3ExprCodeTemp(pParse, pRight, pFreeRight);
 }
 
 /*
-** Measure the number of characters needed to output the given
-** identifier.  The number returned includes any quotes used
-** but does not include the null terminator.
-**
-** The estimate is conservative.  It might be larger that what is
-** really needed.
+** Generate code for a comparison operator.
 */
-static int identLength(const char *z){
-  int n;
-  for(n=0; *z; n++, z++){
-    if( *z=='"' ){ n++; }
+static int codeCompare(
+  Parse *pParse,    /* The parsing (and code generating) context */
+  Expr *pLeft,      /* The left operand */
+  Expr *pRight,     /* The right operand */
+  int opcode,       /* The comparison opcode */
+  int in1, int in2, /* Register holding operands */
+  int dest,         /* Jump here if true.  */
+  int jumpIfNull    /* If true, jump if either operand is NULL */
+){
+  int p5;
+  int addr;
+  CollSeq *p4;
+
+  p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
+  p5 = binaryCompareP5(pLeft, pRight, jumpIfNull);
+  addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1,
+                           (void*)p4, P4_COLLSEQ);
+  sqlite3VdbeChangeP5(pParse->pVdbe, (u8)p5);
+  if( (p5 & SQLITE_AFF_MASK)!=SQLITE_AFF_NONE ){
+    sqlite3ExprCacheAffinityChange(pParse, in1, 1);
+    sqlite3ExprCacheAffinityChange(pParse, in2, 1);
   }
-  return n + 2;
+  return addr;
 }
 
+#if SQLITE_MAX_EXPR_DEPTH>0
 /*
-** Write an identifier onto the end of the given string.  Add
-** quote characters as needed.
+** Check that argument nHeight is less than or equal to the maximum
+** expression depth allowed. If it is not, leave an error message in
+** pParse.
 */
-static void identPut(char *z, int *pIdx, char *zSignedIdent){
-  unsigned char *zIdent = (unsigned char*)zSignedIdent;
-  int i, j, needQuote;
-  i = *pIdx;
-  for(j=0; zIdent[j]; j++){
-    if( !isalnum(zIdent[j]) && zIdent[j]!='_' ) break;
-  }
-  needQuote =  zIdent[j]!=0 || isdigit(zIdent[0])
-                  || sqlite3KeywordCode(zIdent, j)!=TK_ID;
-  if( needQuote ) z[i++] = '"';
-  for(j=0; zIdent[j]; j++){
-    z[i++] = zIdent[j];
-    if( zIdent[j]=='"' ) z[i++] = '"';
+SQLITE_PRIVATE int sqlite3ExprCheckHeight(Parse *pParse, int nHeight){
+  int rc = SQLITE_OK;
+  int mxHeight = pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH];
+  if( nHeight>mxHeight ){
+    sqlite3ErrorMsg(pParse, 
+       "Expression tree is too large (maximum depth %d)", mxHeight
+    );
+    rc = SQLITE_ERROR;
   }
-  if( needQuote ) z[i++] = '"';
-  z[i] = 0;
-  *pIdx = i;
+  return rc;
 }
 
-/*
-** Generate a CREATE TABLE statement appropriate for the given
-** table.  Memory to hold the text of the statement is obtained
-** from sqliteMalloc() and must be freed by the calling function.
+/* The following three functions, heightOfExpr(), heightOfExprList()
+** and heightOfSelect(), are used to determine the maximum height
+** of any expression tree referenced by the structure passed as the
+** first argument.
+**
+** If this maximum height is greater than the current value pointed
+** to by pnHeight, the second parameter, then set *pnHeight to that
+** value.
 */
-static char *createTableStmt(sqlite3 *db, Table *p, int isTemp){
-  int i, k, n;
-  char *zStmt;
-  char *zSep, *zSep2, *zEnd, *z;
-  Column *pCol;
-  n = 0;
-  for(pCol = p->aCol, i=0; i<p->nCol; i++, pCol++){
-    n += identLength(pCol->zName);
-    z = pCol->zType;
-    if( z ){
-      n += (strlen(z) + 1);
+static void heightOfExpr(Expr *p, int *pnHeight){
+  if( p ){
+    if( p->nHeight>*pnHeight ){
+      *pnHeight = p->nHeight;
     }
   }
-  n += identLength(p->zName);
-  if( n<50 ){
-    zSep = "";
-    zSep2 = ",";
-    zEnd = ")";
-  }else{
-    zSep = "\n  ";
-    zSep2 = ",\n  ";
-    zEnd = "\n)";
-  }
-  n += 35 + 6*p->nCol;
-  zStmt = sqlite3_malloc( n );
-  if( zStmt==0 ){
-    db->mallocFailed = 1;
-    return 0;
-  }
-  sqlite3_snprintf(n, zStmt,
-                  !OMIT_TEMPDB&&isTemp ? "CREATE TEMP TABLE ":"CREATE TABLE ");
-  k = strlen(zStmt);
-  identPut(zStmt, &k, p->zName);
-  zStmt[k++] = '(';
-  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
-    sqlite3_snprintf(n-k, &zStmt[k], zSep);
-    k += strlen(&zStmt[k]);
-    zSep = zSep2;
-    identPut(zStmt, &k, pCol->zName);
-    if( (z = pCol->zType)!=0 ){
-      zStmt[k++] = ' ';
-      assert( strlen(z)+k+1<=n );
-      sqlite3_snprintf(n-k, &zStmt[k], "%s", z);
-      k += strlen(z);
+}
+static void heightOfExprList(ExprList *p, int *pnHeight){
+  if( p ){
+    int i;
+    for(i=0; i<p->nExpr; i++){
+      heightOfExpr(p->a[i].pExpr, pnHeight);
     }
   }
-  sqlite3_snprintf(n-k, &zStmt[k], "%s", zEnd);
-  return zStmt;
+}
+static void heightOfSelect(Select *p, int *pnHeight){
+  if( p ){
+    heightOfExpr(p->pWhere, pnHeight);
+    heightOfExpr(p->pHaving, pnHeight);
+    heightOfExpr(p->pLimit, pnHeight);
+    heightOfExpr(p->pOffset, pnHeight);
+    heightOfExprList(p->pEList, pnHeight);
+    heightOfExprList(p->pGroupBy, pnHeight);
+    heightOfExprList(p->pOrderBy, pnHeight);
+    heightOfSelect(p->pPrior, pnHeight);
+  }
 }
 
 /*
-** This routine is called to report the final ")" that terminates
-** a CREATE TABLE statement.
-**
-** The table structure that other action routines have been building
-** is added to the internal hash tables, assuming no errors have
-** occurred.
-**
-** An entry for the table is made in the master table on disk, unless
-** this is a temporary table or db->init.busy==1.  When db->init.busy==1
-** it means we are reading the sqlite_master table because we just
-** connected to the database or because the sqlite_master table has
-** recently changed, so the entry for this table already exists in
-** the sqlite_master table.  We do not want to create it again.
-**
-** If the pSelect argument is not NULL, it means that this routine
-** was called to create a table generated from a 
-** "CREATE TABLE ... AS SELECT ..." statement.  The column names of
-** the new table will match the result set of the SELECT.
+** Set the Expr.nHeight variable in the structure passed as an 
+** argument. An expression with no children, Expr.pList or 
+** Expr.pSelect member has a height of 1. Any other expression
+** has a height equal to the maximum height of any other 
+** referenced Expr plus one.
 */
-SQLITE_PRIVATE void sqlite3EndTable(
-  Parse *pParse,          /* Parse context */
-  Token *pCons,           /* The ',' token after the last column defn. */
-  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
-  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
-){
-  Table *p;
-  sqlite3 *db = pParse->db;
-  int iDb;
-
-  if( (pEnd==0 && pSelect==0) || pParse->nErr || db->mallocFailed ) {
-    return;
+static void exprSetHeight(Expr *p){
+  int nHeight = 0;
+  heightOfExpr(p->pLeft, &nHeight);
+  heightOfExpr(p->pRight, &nHeight);
+  if( ExprHasProperty(p, EP_xIsSelect) ){
+    heightOfSelect(p->x.pSelect, &nHeight);
+  }else{
+    heightOfExprList(p->x.pList, &nHeight);
   }
-  p = pParse->pNewTable;
-  if( p==0 ) return;
+  p->nHeight = nHeight + 1;
+}
 
-  assert( !db->init.busy || !pSelect );
+/*
+** Set the Expr.nHeight variable using the exprSetHeight() function. If
+** the height is greater than the maximum allowed expression depth,
+** leave an error in pParse.
+*/
+SQLITE_PRIVATE void sqlite3ExprSetHeight(Parse *pParse, Expr *p){
+  exprSetHeight(p);
+  sqlite3ExprCheckHeight(pParse, p->nHeight);
+}
 
-  iDb = sqlite3SchemaToIndex(db, p->pSchema);
+/*
+** Return the maximum height of any expression tree referenced
+** by the select statement passed as an argument.
+*/
+SQLITE_PRIVATE int sqlite3SelectExprHeight(Select *p){
+  int nHeight = 0;
+  heightOfSelect(p, &nHeight);
+  return nHeight;
+}
+#else
+  #define exprSetHeight(y)
+#endif /* SQLITE_MAX_EXPR_DEPTH>0 */
 
-#ifndef SQLITE_OMIT_CHECK
-  /* Resolve names in all CHECK constraint expressions.
-  */
-  if( p->pCheck ){
-    SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
-    NameContext sNC;                /* Name context for pParse->pNewTable */
+/*
+** This routine is the core allocator for Expr nodes.
+**
+** Construct a new expression node and return a pointer to it.  Memory
+** for this node and for the pToken argument is a single allocation
+** obtained from sqlite3DbMalloc().  The calling function
+** is responsible for making sure the node eventually gets freed.
+**
+** If dequote is true, then the token (if it exists) is dequoted.
+** If dequote is false, no dequoting is performance.  The deQuote
+** parameter is ignored if pToken is NULL or if the token does not
+** appear to be quoted.  If the quotes were of the form "..." (double-quotes)
+** then the EP_DblQuoted flag is set on the expression node.
+**
+** Special case:  If op==TK_INTEGER and pToken points to a string that
+** can be translated into a 32-bit integer, then the token is not
+** stored in u.zToken.  Instead, the integer values is written
+** into u.iValue and the EP_IntValue flag is set.  No extra storage
+** is allocated to hold the integer text and the dequote flag is ignored.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprAlloc(
+  sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */
+  int op,                 /* Expression opcode */
+  const Token *pToken,    /* Token argument.  Might be NULL */
+  int dequote             /* True to dequote */
+){
+  Expr *pNew;
+  int nExtra = 0;
+  int iValue = 0;
 
-    memset(&sNC, 0, sizeof(sNC));
-    memset(&sSrc, 0, sizeof(sSrc));
-    sSrc.nSrc = 1;
-    sSrc.a[0].zName = p->zName;
-    sSrc.a[0].pTab = p;
-    sSrc.a[0].iCursor = -1;
-    sNC.pParse = pParse;
-    sNC.pSrcList = &sSrc;
-    sNC.isCheck = 1;
-    if( sqlite3ExprResolveNames(&sNC, p->pCheck) ){
-      return;
+  if( pToken ){
+    if( op!=TK_INTEGER || pToken->z==0
+          || sqlite3GetInt32(pToken->z, &iValue)==0 ){
+      nExtra = pToken->n+1;
     }
   }
-#endif /* !defined(SQLITE_OMIT_CHECK) */
-
-  /* If the db->init.busy is 1 it means we are reading the SQL off the
-  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
-  ** So do not write to the disk again.  Extract the root page number
-  ** for the table from the db->init.newTnum field.  (The page number
-  ** should have been put there by the sqliteOpenCb routine.)
-  */
-  if( db->init.busy ){
-    p->tnum = db->init.newTnum;
-  }
-
-  /* If not initializing, then create a record for the new table
-  ** in the SQLITE_MASTER table of the database.  The record number
-  ** for the new table entry should already be on the stack.
-  **
-  ** If this is a TEMPORARY table, write the entry into the auxiliary
-  ** file instead of into the main database file.
-  */
-  if( !db->init.busy ){
-    int n;
-    Vdbe *v;
-    char *zType;    /* "view" or "table" */
-    char *zType2;   /* "VIEW" or "TABLE" */
-    char *zStmt;    /* Text of the CREATE TABLE or CREATE VIEW statement */
-
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) return;
-
-    sqlite3VdbeAddOp1(v, OP_Close, 0);
-
-    /* Create the rootpage for the new table and push it onto the stack.
-    ** A view has no rootpage, so just push a zero onto the stack for
-    ** views.  Initialize zType at the same time.
-    */
-    if( p->pSelect==0 ){
-      /* A regular table */
-      zType = "table";
-      zType2 = "TABLE";
-#ifndef SQLITE_OMIT_VIEW
-    }else{
-      /* A view */
-      zType = "view";
-      zType2 = "VIEW";
-#endif
+  pNew = sqlite3DbMallocZero(db, sizeof(Expr)+nExtra);
+  if( pNew ){
+    pNew->op = (u8)op;
+    pNew->iAgg = -1;
+    if( pToken ){
+      if( nExtra==0 ){
+        pNew->flags |= EP_IntValue;
+        pNew->u.iValue = iValue;
+      }else{
+        int c;
+        pNew->u.zToken = (char*)&pNew[1];
+        memcpy(pNew->u.zToken, pToken->z, pToken->n);
+        pNew->u.zToken[pToken->n] = 0;
+        if( dequote && nExtra>=3 
+             && ((c = pToken->z[0])=='\'' || c=='"' || c=='[' || c=='`') ){
+          sqlite3Dequote(pNew->u.zToken);
+          if( c=='"' ) pNew->flags |= EP_DblQuoted;
+        }
+      }
     }
+#if SQLITE_MAX_EXPR_DEPTH>0
+    pNew->nHeight = 1;
+#endif  
+  }
+  return pNew;
+}
 
-    /* If this is a CREATE TABLE xx AS SELECT ..., execute the SELECT
-    ** statement to populate the new table. The root-page number for the
-    ** new table is on the top of the vdbe stack.
-    **
-    ** Once the SELECT has been coded by sqlite3Select(), it is in a
-    ** suitable state to query for the column names and types to be used
-    ** by the new table.
-    **
-    ** A shared-cache write-lock is not required to write to the new table,
-    ** as a schema-lock must have already been obtained to create it. Since
-    ** a schema-lock excludes all other database users, the write-lock would
-    ** be redundant.
-    */
-    if( pSelect ){
-      SelectDest dest;
-      Table *pSelTab;
+/*
+** Allocate a new expression node from a zero-terminated token that has
+** already been dequoted.
+*/
+SQLITE_PRIVATE Expr *sqlite3Expr(
+  sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */
+  int op,                 /* Expression opcode */
+  const char *zToken      /* Token argument.  Might be NULL */
+){
+  Token x;
+  x.z = zToken;
+  x.n = zToken ? sqlite3Strlen30(zToken) : 0;
+  return sqlite3ExprAlloc(db, op, &x, 0);
+}
 
-      sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
-      sqlite3VdbeChangeP5(v, 1);
-      pParse->nTab = 2;
-      sqlite3SelectDestInit(&dest, SRT_Table, 1);
-      sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
-      sqlite3VdbeAddOp1(v, OP_Close, 1);
-      if( pParse->nErr==0 ){
-        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
-        if( pSelTab==0 ) return;
-        assert( p->aCol==0 );
-        p->nCol = pSelTab->nCol;
-        p->aCol = pSelTab->aCol;
-        pSelTab->nCol = 0;
-        pSelTab->aCol = 0;
-        sqlite3DeleteTable(pSelTab);
+/*
+** Attach subtrees pLeft and pRight to the Expr node pRoot.
+**
+** If pRoot==NULL that means that a memory allocation error has occurred.
+** In that case, delete the subtrees pLeft and pRight.
+*/
+SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(
+  sqlite3 *db,
+  Expr *pRoot,
+  Expr *pLeft,
+  Expr *pRight
+){
+  if( pRoot==0 ){
+    assert( db->mallocFailed );
+    sqlite3ExprDelete(db, pLeft);
+    sqlite3ExprDelete(db, pRight);
+  }else{
+    if( pRight ){
+      pRoot->pRight = pRight;
+      if( pRight->flags & EP_ExpCollate ){
+        pRoot->flags |= EP_ExpCollate;
+        pRoot->pColl = pRight->pColl;
       }
     }
-
-    /* Compute the complete text of the CREATE statement */
-    if( pSelect ){
-      zStmt = createTableStmt(db, p, p->pSchema==db->aDb[1].pSchema);
-    }else{
-      n = pEnd->z - pParse->sNameToken.z + 1;
-      zStmt = sqlite3MPrintf(db, 
-          "CREATE %s %.*s", zType2, n, pParse->sNameToken.z
-      );
+    if( pLeft ){
+      pRoot->pLeft = pLeft;
+      if( pLeft->flags & EP_ExpCollate ){
+        pRoot->flags |= EP_ExpCollate;
+        pRoot->pColl = pLeft->pColl;
+      }
     }
+    exprSetHeight(pRoot);
+  }
+}
 
-    /* A slot for the record has already been allocated in the 
-    ** SQLITE_MASTER table.  We just need to update that slot with all
-    ** the information we've collected.  The rowid for the preallocated
-    ** slot is the 2nd item on the stack.  The top of the stack is the
-    ** root page for the new table (or a 0 if this is a view).
-    */
-    sqlite3NestedParse(pParse,
-      "UPDATE %Q.%s "
-         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=#%d, sql=%Q "
-       "WHERE rowid=#%d",
-      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
-      zType,
-      p->zName,
-      p->zName,
-      pParse->regRoot,
-      zStmt,
-      pParse->regRowid
-    );
-    sqlite3_free(zStmt);
-    sqlite3ChangeCookie(pParse, iDb);
+/*
+** Allocate a Expr node which joins as many as two subtrees.
+**
+** One or both of the subtrees can be NULL.  Return a pointer to the new
+** Expr node.  Or, if an OOM error occurs, set pParse->db->mallocFailed,
+** free the subtrees and return NULL.
+*/
+SQLITE_PRIVATE Expr *sqlite3PExpr(
+  Parse *pParse,          /* Parsing context */
+  int op,                 /* Expression opcode */
+  Expr *pLeft,            /* Left operand */
+  Expr *pRight,           /* Right operand */
+  const Token *pToken     /* Argument token */
+){
+  Expr *p = sqlite3ExprAlloc(pParse->db, op, pToken, 1);
+  sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
+  return p;
+}
 
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-    /* Check to see if we need to create an sqlite_sequence table for
-    ** keeping track of autoincrement keys.
-    */
-    if( p->autoInc ){
-      Db *pDb = &db->aDb[iDb];
-      if( pDb->pSchema->pSeqTab==0 ){
-        sqlite3NestedParse(pParse,
-          "CREATE TABLE %Q.sqlite_sequence(name,seq)",
-          pDb->zName
-        );
-      }
-    }
-#endif
+/*
+** Join two expressions using an AND operator.  If either expression is
+** NULL, then just return the other expression.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){
+  if( pLeft==0 ){
+    return pRight;
+  }else if( pRight==0 ){
+    return pLeft;
+  }else{
+    Expr *pNew = sqlite3ExprAlloc(db, TK_AND, 0, 0);
+    sqlite3ExprAttachSubtrees(db, pNew, pLeft, pRight);
+    return pNew;
+  }
+}
 
-    /* Reparse everything to update our internal data structures */
-    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0,
-        sqlite3MPrintf(db, "tbl_name='%q'",p->zName), P4_DYNAMIC);
+/*
+** Construct a new expression node for a function with multiple
+** arguments.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){
+  Expr *pNew;
+  sqlite3 *db = pParse->db;
+  assert( pToken );
+  pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1);
+  if( pNew==0 ){
+    sqlite3ExprListDelete(db, pList); /* Avoid memory leak when malloc fails */
+    return 0;
   }
+  pNew->x.pList = pList;
+  assert( !ExprHasProperty(pNew, EP_xIsSelect) );
+  sqlite3ExprSetHeight(pParse, pNew);
+  return pNew;
+}
 
+/*
+** Assign a variable number to an expression that encodes a wildcard
+** in the original SQL statement.  
+**
+** Wildcards consisting of a single "?" are assigned the next sequential
+** variable number.
+**
+** Wildcards of the form "?nnn" are assigned the number "nnn".  We make
+** sure "nnn" is not too be to avoid a denial of service attack when
+** the SQL statement comes from an external source.
+**
+** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number
+** as the previous instance of the same wildcard.  Or if this is the first
+** instance of the wildcard, the next sequenial variable number is
+** assigned.
+*/
+SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
+  sqlite3 *db = pParse->db;
+  const char *z;
 
-  /* Add the table to the in-memory representation of the database.
-  */
-  if( db->init.busy && pParse->nErr==0 ){
-    Table *pOld;
-    FKey *pFKey; 
-    Schema *pSchema = p->pSchema;
-    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName, strlen(p->zName)+1,p);
-    if( pOld ){
-      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
-      db->mallocFailed = 1;
-      return;
+  if( pExpr==0 ) return;
+  assert( !ExprHasAnyProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
+  z = pExpr->u.zToken;
+  assert( z!=0 );
+  assert( z[0]!=0 );
+  if( z[1]==0 ){
+    /* Wildcard of the form "?".  Assign the next variable number */
+    assert( z[0]=='?' );
+    pExpr->iTable = ++pParse->nVar;
+  }else if( z[0]=='?' ){
+    /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
+    ** use it as the variable number */
+    int i;
+    pExpr->iTable = i = atoi((char*)&z[1]);
+    testcase( i==0 );
+    testcase( i==1 );
+    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
+    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
+    if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+      sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
+          db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
     }
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-    for(pFKey=p->pFKey; pFKey; pFKey=pFKey->pNextFrom){
-      void *data;
-      int nTo = strlen(pFKey->zTo) + 1;
-      pFKey->pNextTo = sqlite3HashFind(&pSchema->aFKey, pFKey->zTo, nTo);
-      data = sqlite3HashInsert(&pSchema->aFKey, pFKey->zTo, nTo, pFKey);
-      if( data==(void *)pFKey ){
-        db->mallocFailed = 1;
+    if( i>pParse->nVar ){
+      pParse->nVar = i;
+    }
+  }else{
+    /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
+    ** number as the prior appearance of the same name, or if the name
+    ** has never appeared before, reuse the same variable number
+    */
+    int i;
+    u32 n;
+    n = sqlite3Strlen30(z);
+    for(i=0; i<pParse->nVarExpr; i++){
+      Expr *pE = pParse->apVarExpr[i];
+      assert( pE!=0 );
+      if( memcmp(pE->u.zToken, z, n)==0 && pE->u.zToken[n]==0 ){
+        pExpr->iTable = pE->iTable;
+        break;
       }
     }
-#endif
-    pParse->pNewTable = 0;
-    db->nTable++;
-    db->flags |= SQLITE_InternChanges;
-
-#ifndef SQLITE_OMIT_ALTERTABLE
-    if( !p->pSelect ){
-      const char *zName = (const char *)pParse->sNameToken.z;
-      int nName;
-      assert( !pSelect && pCons && pEnd );
-      if( pCons->z==0 ){
-        pCons = pEnd;
+    if( i>=pParse->nVarExpr ){
+      pExpr->iTable = ++pParse->nVar;
+      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
+        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
+        pParse->apVarExpr =
+            sqlite3DbReallocOrFree(
+              db,
+              pParse->apVarExpr,
+              pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
+            );
+      }
+      if( !db->mallocFailed ){
+        assert( pParse->apVarExpr!=0 );
+        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
       }
-      nName = (const char *)pCons->z - zName;
-      p->addColOffset = 13 + sqlite3Utf8CharLen(zName, nName);
     }
-#endif
+  } 
+  if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+    sqlite3ErrorMsg(pParse, "too many SQL variables");
   }
 }
 
-#ifndef SQLITE_OMIT_VIEW
 /*
-** The parser calls this routine in order to create a new VIEW
+** Clear an expression structure without deleting the structure itself.
+** Substructure is deleted.
 */
-SQLITE_PRIVATE void sqlite3CreateView(
-  Parse *pParse,     /* The parsing context */
-  Token *pBegin,     /* The CREATE token that begins the statement */
-  Token *pName1,     /* The token that holds the name of the view */
-  Token *pName2,     /* The token that holds the name of the view */
-  Select *pSelect,   /* A SELECT statement that will become the new view */
-  int isTemp,        /* TRUE for a TEMPORARY view */
-  int noErr          /* Suppress error messages if VIEW already exists */
-){
-  Table *p;
-  int n;
-  const unsigned char *z;
-  Token sEnd;
-  DbFixer sFix;
-  Token *pName;
-  int iDb;
-  sqlite3 *db = pParse->db;
-
-  if( pParse->nVar>0 ){
-    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
-    sqlite3SelectDelete(pSelect);
-    return;
-  }
-  sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
-  p = pParse->pNewTable;
-  if( p==0 || pParse->nErr ){
-    sqlite3SelectDelete(pSelect);
-    return;
-  }
-  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
-  iDb = sqlite3SchemaToIndex(db, p->pSchema);
-  if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
-    && sqlite3FixSelect(&sFix, pSelect)
-  ){
-    sqlite3SelectDelete(pSelect);
-    return;
-  }
-
-  /* Make a copy of the entire SELECT statement that defines the view.
-  ** This will force all the Expr.token.z values to be dynamically
-  ** allocated rather than point to the input string - which means that
-  ** they will persist after the current sqlite3_exec() call returns.
-  */
-  p->pSelect = sqlite3SelectDup(db, pSelect);
-  sqlite3SelectDelete(pSelect);
-  if( db->mallocFailed ){
-    return;
-  }
-  if( !db->init.busy ){
-    sqlite3ViewGetColumnNames(pParse, p);
-  }
-
-  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
-  ** the end.
-  */
-  sEnd = pParse->sLastToken;
-  if( sEnd.z[0]!=0 && sEnd.z[0]!=';' ){
-    sEnd.z += sEnd.n;
+SQLITE_PRIVATE void sqlite3ExprClear(sqlite3 *db, Expr *p){
+  assert( p!=0 );
+  if( !ExprHasAnyProperty(p, EP_TokenOnly) ){
+    sqlite3ExprDelete(db, p->pLeft);
+    sqlite3ExprDelete(db, p->pRight);
+    if( !ExprHasProperty(p, EP_Reduced) && (p->flags2 & EP2_MallocedToken)!=0 ){
+      sqlite3DbFree(db, p->u.zToken);
+    }
+    if( ExprHasProperty(p, EP_xIsSelect) ){
+      sqlite3SelectDelete(db, p->x.pSelect);
+    }else{
+      sqlite3ExprListDelete(db, p->x.pList);
+    }
   }
-  sEnd.n = 0;
-  n = sEnd.z - pBegin->z;
-  z = (const unsigned char*)pBegin->z;
-  while( n>0 && (z[n-1]==';' || isspace(z[n-1])) ){ n--; }
-  sEnd.z = &z[n-1];
-  sEnd.n = 1;
-
-  /* Use sqlite3EndTable() to add the view to the SQLITE_MASTER table */
-  sqlite3EndTable(pParse, 0, &sEnd, 0);
-  return;
 }
-#endif /* SQLITE_OMIT_VIEW */
 
-#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
 /*
-** The Table structure pTable is really a VIEW.  Fill in the names of
-** the columns of the view in the pTable structure.  Return the number
-** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
+** Recursively delete an expression tree.
 */
-SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
-  Table *pSelTab;   /* A fake table from which we get the result set */
-  Select *pSel;     /* Copy of the SELECT that implements the view */
-  int nErr = 0;     /* Number of errors encountered */
-  int n;            /* Temporarily holds the number of cursors assigned */
-  sqlite3 *db = pParse->db;  /* Database connection for malloc errors */
-  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
-
-  assert( pTable );
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( sqlite3VtabCallConnect(pParse, pTable) ){
-    return SQLITE_ERROR;
+SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
+  if( p==0 ) return;
+  sqlite3ExprClear(db, p);
+  if( !ExprHasProperty(p, EP_Static) ){
+    sqlite3DbFree(db, p);
   }
-  if( IsVirtual(pTable) ) return 0;
-#endif
-
-#ifndef SQLITE_OMIT_VIEW
-  /* A positive nCol means the columns names for this view are
-  ** already known.
-  */
-  if( pTable->nCol>0 ) return 0;
+}
 
-  /* A negative nCol is a special marker meaning that we are currently
-  ** trying to compute the column names.  If we enter this routine with
-  ** a negative nCol, it means two or more views form a loop, like this:
-  **
-  **     CREATE VIEW one AS SELECT * FROM two;
-  **     CREATE VIEW two AS SELECT * FROM one;
-  **
-  ** Actually, this error is caught previously and so the following test
-  ** should always fail.  But we will leave it in place just to be safe.
-  */
-  if( pTable->nCol<0 ){
-    sqlite3ErrorMsg(pParse, "view %s is circularly defined", pTable->zName);
-    return 1;
-  }
-  assert( pTable->nCol>=0 );
+/*
+** Return the number of bytes allocated for the expression structure 
+** passed as the first argument. This is always one of EXPR_FULLSIZE,
+** EXPR_REDUCEDSIZE or EXPR_TOKENONLYSIZE.
+*/
+static int exprStructSize(Expr *p){
+  if( ExprHasProperty(p, EP_TokenOnly) ) return EXPR_TOKENONLYSIZE;
+  if( ExprHasProperty(p, EP_Reduced) ) return EXPR_REDUCEDSIZE;
+  return EXPR_FULLSIZE;
+}
 
-  /* If we get this far, it means we need to compute the table names.
-  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
-  ** "*" elements in the results set of the view and will assign cursors
-  ** to the elements of the FROM clause.  But we do not want these changes
-  ** to be permanent.  So the computation is done on a copy of the SELECT
-  ** statement that defines the view.
-  */
-  assert( pTable->pSelect );
-  pSel = sqlite3SelectDup(db, pTable->pSelect);
-  if( pSel ){
-    n = pParse->nTab;
-    sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
-    pTable->nCol = -1;
-#ifndef SQLITE_OMIT_AUTHORIZATION
-    xAuth = db->xAuth;
-    db->xAuth = 0;
-    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
-    db->xAuth = xAuth;
-#else
-    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
-#endif
-    pParse->nTab = n;
-    if( pSelTab ){
-      assert( pTable->aCol==0 );
-      pTable->nCol = pSelTab->nCol;
-      pTable->aCol = pSelTab->aCol;
-      pSelTab->nCol = 0;
-      pSelTab->aCol = 0;
-      sqlite3DeleteTable(pSelTab);
-      pTable->pSchema->flags |= DB_UnresetViews;
+/*
+** The dupedExpr*Size() routines each return the number of bytes required
+** to store a copy of an expression or expression tree.  They differ in
+** how much of the tree is measured.
+**
+**     dupedExprStructSize()     Size of only the Expr structure 
+**     dupedExprNodeSize()       Size of Expr + space for token
+**     dupedExprSize()           Expr + token + subtree components
+**
+***************************************************************************
+**
+** The dupedExprStructSize() function returns two values OR-ed together:  
+** (1) the space required for a copy of the Expr structure only and 
+** (2) the EP_xxx flags that indicate what the structure size should be.
+** The return values is always one of:
+**
+**      EXPR_FULLSIZE
+**      EXPR_REDUCEDSIZE   | EP_Reduced
+**      EXPR_TOKENONLYSIZE | EP_TokenOnly
+**
+** The size of the structure can be found by masking the return value
+** of this routine with 0xfff.  The flags can be found by masking the
+** return value with EP_Reduced|EP_TokenOnly.
+**
+** Note that with flags==EXPRDUP_REDUCE, this routines works on full-size
+** (unreduced) Expr objects as they or originally constructed by the parser.
+** During expression analysis, extra information is computed and moved into
+** later parts of teh Expr object and that extra information might get chopped
+** off if the expression is reduced.  Note also that it does not work to
+** make a EXPRDUP_REDUCE copy of a reduced expression.  It is only legal
+** to reduce a pristine expression tree from the parser.  The implementation
+** of dupedExprStructSize() contain multiple assert() statements that attempt
+** to enforce this constraint.
+*/
+static int dupedExprStructSize(Expr *p, int flags){
+  int nSize;
+  assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */
+  if( 0==(flags&EXPRDUP_REDUCE) ){
+    nSize = EXPR_FULLSIZE;
+  }else{
+    assert( !ExprHasAnyProperty(p, EP_TokenOnly|EP_Reduced) );
+    assert( !ExprHasProperty(p, EP_FromJoin) ); 
+    assert( (p->flags2 & EP2_MallocedToken)==0 );
+    assert( (p->flags2 & EP2_Irreducible)==0 );
+    if( p->pLeft || p->pRight || p->pColl || p->x.pList ){
+      nSize = EXPR_REDUCEDSIZE | EP_Reduced;
     }else{
-      pTable->nCol = 0;
-      nErr++;
+      nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
     }
-    sqlite3SelectDelete(pSel);
-  } else {
-    nErr++;
   }
-#endif /* SQLITE_OMIT_VIEW */
-  return nErr;  
+  return nSize;
 }
-#endif /* !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) */
 
-#ifndef SQLITE_OMIT_VIEW
 /*
-** Clear the column names from every VIEW in database idx.
+** This function returns the space in bytes required to store the copy 
+** of the Expr structure and a copy of the Expr.u.zToken string (if that
+** string is defined.)
 */
-static void sqliteViewResetAll(sqlite3 *db, int idx){
-  HashElem *i;
-  if( !DbHasProperty(db, idx, DB_UnresetViews) ) return;
-  for(i=sqliteHashFirst(&db->aDb[idx].pSchema->tblHash); i;i=sqliteHashNext(i)){
-    Table *pTab = sqliteHashData(i);
-    if( pTab->pSelect ){
-      sqliteResetColumnNames(pTab);
-    }
+static int dupedExprNodeSize(Expr *p, int flags){
+  int nByte = dupedExprStructSize(p, flags) & 0xfff;
+  if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+    nByte += sqlite3Strlen30(p->u.zToken)+1;
   }
-  DbClearProperty(db, idx, DB_UnresetViews);
+  return ROUND8(nByte);
 }
-#else
-# define sqliteViewResetAll(A,B)
-#endif /* SQLITE_OMIT_VIEW */
 
 /*
-** This function is called by the VDBE to adjust the internal schema
-** used by SQLite when the btree layer moves a table root page. The
-** root-page of a table or index in database iDb has changed from iFrom
-** to iTo.
+** Return the number of bytes required to create a duplicate of the 
+** expression passed as the first argument. The second argument is a
+** mask containing EXPRDUP_XXX flags.
 **
-** Ticket #1728:  The symbol table might still contain information
-** on tables and/or indices that are the process of being deleted.
-** If you are unlucky, one of those deleted indices or tables might
-** have the same rootpage number as the real table or index that is
-** being moved.  So we cannot stop searching after the first match 
-** because the first match might be for one of the deleted indices
-** or tables and not the table/index that is actually being moved.
-** We must continue looping until all tables and indices with
-** rootpage==iFrom have been converted to have a rootpage of iTo
-** in order to be certain that we got the right one.
+** The value returned includes space to create a copy of the Expr struct
+** itself and the buffer referred to by Expr.u.zToken, if any.
+**
+** If the EXPRDUP_REDUCE flag is set, then the return value includes 
+** space to duplicate all Expr nodes in the tree formed by Expr.pLeft 
+** and Expr.pRight variables (but not for any structures pointed to or 
+** descended from the Expr.x.pList or Expr.x.pSelect variables).
 */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-SQLITE_PRIVATE void sqlite3RootPageMoved(Db *pDb, int iFrom, int iTo){
-  HashElem *pElem;
-  Hash *pHash;
-
-  pHash = &pDb->pSchema->tblHash;
-  for(pElem=sqliteHashFirst(pHash); pElem; pElem=sqliteHashNext(pElem)){
-    Table *pTab = sqliteHashData(pElem);
-    if( pTab->tnum==iFrom ){
-      pTab->tnum = iTo;
-    }
-  }
-  pHash = &pDb->pSchema->idxHash;
-  for(pElem=sqliteHashFirst(pHash); pElem; pElem=sqliteHashNext(pElem)){
-    Index *pIdx = sqliteHashData(pElem);
-    if( pIdx->tnum==iFrom ){
-      pIdx->tnum = iTo;
+static int dupedExprSize(Expr *p, int flags){
+  int nByte = 0;
+  if( p ){
+    nByte = dupedExprNodeSize(p, flags);
+    if( flags&EXPRDUP_REDUCE ){
+      nByte += dupedExprSize(p->pLeft, flags) + dupedExprSize(p->pRight, flags);
     }
   }
+  return nByte;
 }
-#endif
 
 /*
-** Write code to erase the table with root-page iTable from database iDb.
-** Also write code to modify the sqlite_master table and internal schema
-** if a root-page of another table is moved by the btree-layer whilst
-** erasing iTable (this can happen with an auto-vacuum database).
-*/ 
-static void destroyRootPage(Parse *pParse, int iTable, int iDb){
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  int r1 = sqlite3GetTempReg(pParse);
-  sqlite3VdbeAddOp3(v, OP_Destroy, iTable, r1, iDb);
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  /* OP_Destroy stores an in integer r1. If this integer
-  ** is non-zero, then it is the root page number of a table moved to
-  ** location iTable. The following code modifies the sqlite_master table to
-  ** reflect this.
-  **
-  ** The "#%d" in the SQL is a special constant that means whatever value
-  ** is on the top of the stack.  See sqlite3RegisterExpr().
-  */
-  sqlite3NestedParse(pParse, 
-     "UPDATE %Q.%s SET rootpage=%d WHERE #%d AND rootpage=#%d",
-     pParse->db->aDb[iDb].zName, SCHEMA_TABLE(iDb), iTable, r1, r1);
-#endif
-  sqlite3ReleaseTempReg(pParse, r1);
-}
-
-/*
-** Write VDBE code to erase table pTab and all associated indices on disk.
-** Code to update the sqlite_master tables and internal schema definitions
-** in case a root-page belonging to another table is moved by the btree layer
-** is also added (this can happen with an auto-vacuum database).
+** This function is similar to sqlite3ExprDup(), except that if pzBuffer 
+** is not NULL then *pzBuffer is assumed to point to a buffer large enough 
+** to store the copy of expression p, the copies of p->u.zToken
+** (if applicable), and the copies of the p->pLeft and p->pRight expressions,
+** if any. Before returning, *pzBuffer is set to the first byte passed the
+** portion of the buffer copied into by this function.
 */
-static void destroyTable(Parse *pParse, Table *pTab){
-#ifdef SQLITE_OMIT_AUTOVACUUM
-  Index *pIdx;
-  int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  destroyRootPage(pParse, pTab->tnum, iDb);
-  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-    destroyRootPage(pParse, pIdx->tnum, iDb);
-  }
-#else
-  /* If the database may be auto-vacuum capable (if SQLITE_OMIT_AUTOVACUUM
-  ** is not defined), then it is important to call OP_Destroy on the
-  ** table and index root-pages in order, starting with the numerically 
-  ** largest root-page number. This guarantees that none of the root-pages
-  ** to be destroyed is relocated by an earlier OP_Destroy. i.e. if the
-  ** following were coded:
-  **
-  ** OP_Destroy 4 0
-  ** ...
-  ** OP_Destroy 5 0
-  **
-  ** and root page 5 happened to be the largest root-page number in the
-  ** database, then root page 5 would be moved to page 4 by the 
-  ** "OP_Destroy 4 0" opcode. The subsequent "OP_Destroy 5 0" would hit
-  ** a free-list page.
-  */
-  int iTab = pTab->tnum;
-  int iDestroyed = 0;
+static Expr *exprDup(sqlite3 *db, Expr *p, int flags, u8 **pzBuffer){
+  Expr *pNew = 0;                      /* Value to return */
+  if( p ){
+    const int isReduced = (flags&EXPRDUP_REDUCE);
+    u8 *zAlloc;
+    u32 staticFlag = 0;
 
-  while( 1 ){
-    Index *pIdx;
-    int iLargest = 0;
+    assert( pzBuffer==0 || isReduced );
 
-    if( iDestroyed==0 || iTab<iDestroyed ){
-      iLargest = iTab;
-    }
-    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-      int iIdx = pIdx->tnum;
-      assert( pIdx->pSchema==pTab->pSchema );
-      if( (iDestroyed==0 || (iIdx<iDestroyed)) && iIdx>iLargest ){
-        iLargest = iIdx;
-      }
-    }
-    if( iLargest==0 ){
-      return;
+    /* Figure out where to write the new Expr structure. */
+    if( pzBuffer ){
+      zAlloc = *pzBuffer;
+      staticFlag = EP_Static;
     }else{
-      int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-      destroyRootPage(pParse, iLargest, iDb);
-      iDestroyed = iLargest;
-    }
-  }
-#endif
-}
-
-/*
-** This routine is called to do the work of a DROP TABLE statement.
-** pName is the name of the table to be dropped.
-*/
-SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
-  Table *pTab;
-  Vdbe *v;
-  sqlite3 *db = pParse->db;
-  int iDb;
-
-  if( pParse->nErr || db->mallocFailed ){
-    goto exit_drop_table;
-  }
-  assert( pName->nSrc==1 );
-  pTab = sqlite3LocateTable(pParse, isView, 
-                            pName->a[0].zName, pName->a[0].zDatabase);
-
-  if( pTab==0 ){
-    if( noErr ){
-      sqlite3ErrorClear(pParse);
+      zAlloc = sqlite3DbMallocRaw(db, dupedExprSize(p, flags));
     }
-    goto exit_drop_table;
-  }
-  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-  assert( iDb>=0 && iDb<db->nDb );
+    pNew = (Expr *)zAlloc;
 
-  /* If pTab is a virtual table, call ViewGetColumnNames() to ensure
-  ** it is initialized.
-  */
-  if( IsVirtual(pTab) && sqlite3ViewGetColumnNames(pParse, pTab) ){
-    goto exit_drop_table;
-  }
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  {
-    int code;
-    const char *zTab = SCHEMA_TABLE(iDb);
-    const char *zDb = db->aDb[iDb].zName;
-    const char *zArg2 = 0;
-    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb)){
-      goto exit_drop_table;
-    }
-    if( isView ){
-      if( !OMIT_TEMPDB && iDb==1 ){
-        code = SQLITE_DROP_TEMP_VIEW;
+    if( pNew ){
+      /* Set nNewSize to the size allocated for the structure pointed to
+      ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or
+      ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed
+      ** by the copy of the p->u.zToken string (if any).
+      */
+      const unsigned nStructSize = dupedExprStructSize(p, flags);
+      const int nNewSize = nStructSize & 0xfff;
+      int nToken;
+      if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+        nToken = sqlite3Strlen30(p->u.zToken) + 1;
       }else{
-        code = SQLITE_DROP_VIEW;
+        nToken = 0;
       }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    }else if( IsVirtual(pTab) ){
-      code = SQLITE_DROP_VTABLE;
-      zArg2 = pTab->pMod->zName;
-#endif
-    }else{
-      if( !OMIT_TEMPDB && iDb==1 ){
-        code = SQLITE_DROP_TEMP_TABLE;
+      if( isReduced ){
+        assert( ExprHasProperty(p, EP_Reduced)==0 );
+        memcpy(zAlloc, p, nNewSize);
       }else{
-        code = SQLITE_DROP_TABLE;
+        int nSize = exprStructSize(p);
+        memcpy(zAlloc, p, nSize);
+        memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
       }
-    }
-    if( sqlite3AuthCheck(pParse, code, pTab->zName, zArg2, zDb) ){
-      goto exit_drop_table;
-    }
-    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
-      goto exit_drop_table;
-    }
-  }
-#endif
-  if( pTab->readOnly || pTab==db->aDb[iDb].pSchema->pSeqTab ){
-    sqlite3ErrorMsg(pParse, "table %s may not be dropped", pTab->zName);
-    goto exit_drop_table;
-  }
-
-#ifndef SQLITE_OMIT_VIEW
-  /* Ensure DROP TABLE is not used on a view, and DROP VIEW is not used
-  ** on a table.
-  */
-  if( isView && pTab->pSelect==0 ){
-    sqlite3ErrorMsg(pParse, "use DROP TABLE to delete table %s", pTab->zName);
-    goto exit_drop_table;
-  }
-  if( !isView && pTab->pSelect ){
-    sqlite3ErrorMsg(pParse, "use DROP VIEW to delete view %s", pTab->zName);
-    goto exit_drop_table;
-  }
-#endif
 
-  /* Generate code to remove the table from the master table
-  ** on disk.
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    Trigger *pTrigger;
-    Db *pDb = &db->aDb[iDb];
-    sqlite3BeginWriteOperation(pParse, 1, iDb);
+      /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
+      pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static);
+      pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
+      pNew->flags |= staticFlag;
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( IsVirtual(pTab) ){
-      Vdbe *v = sqlite3GetVdbe(pParse);
-      if( v ){
-        sqlite3VdbeAddOp0(v, OP_VBegin);
+      /* Copy the p->u.zToken string, if any. */
+      if( nToken ){
+        char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
+        memcpy(zToken, p->u.zToken, nToken);
       }
-    }
-#endif
-
-    /* Drop all triggers associated with the table being dropped. Code
-    ** is generated to remove entries from sqlite_master and/or
-    ** sqlite_temp_master if required.
-    */
-    pTrigger = pTab->pTrigger;
-    while( pTrigger ){
-      assert( pTrigger->pSchema==pTab->pSchema || 
-          pTrigger->pSchema==db->aDb[1].pSchema );
-      sqlite3DropTriggerPtr(pParse, pTrigger);
-      pTrigger = pTrigger->pNext;
-    }
-
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-    /* Remove any entries of the sqlite_sequence table associated with
-    ** the table being dropped. This is done before the table is dropped
-    ** at the btree level, in case the sqlite_sequence table needs to
-    ** move as a result of the drop (can happen in auto-vacuum mode).
-    */
-    if( pTab->autoInc ){
-      sqlite3NestedParse(pParse,
-        "DELETE FROM %s.sqlite_sequence WHERE name=%Q",
-        pDb->zName, pTab->zName
-      );
-    }
-#endif
-
-    /* Drop all SQLITE_MASTER table and index entries that refer to the
-    ** table. The program name loops through the master table and deletes
-    ** every row that refers to a table of the same name as the one being
-    ** dropped. Triggers are handled seperately because a trigger can be
-    ** created in the temp database that refers to a table in another
-    ** database.
-    */
-    sqlite3NestedParse(pParse, 
-        "DELETE FROM %Q.%s WHERE tbl_name=%Q and type!='trigger'",
-        pDb->zName, SCHEMA_TABLE(iDb), pTab->zName);
 
-    /* Drop any statistics from the sqlite_stat1 table, if it exists */
-    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
-      sqlite3NestedParse(pParse,
-        "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q", pDb->zName, pTab->zName
-      );
-    }
+      if( 0==((p->flags|pNew->flags) & EP_TokenOnly) ){
+        /* Fill in the pNew->x.pSelect or pNew->x.pList member. */
+        if( ExprHasProperty(p, EP_xIsSelect) ){
+          pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, isReduced);
+        }else{
+          pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, isReduced);
+        }
+      }
 
-    if( !isView && !IsVirtual(pTab) ){
-      destroyTable(pParse, pTab);
-    }
+      /* Fill in pNew->pLeft and pNew->pRight. */
+      if( ExprHasAnyProperty(pNew, EP_Reduced|EP_TokenOnly) ){
+        zAlloc += dupedExprNodeSize(p, flags);
+        if( ExprHasProperty(pNew, EP_Reduced) ){
+          pNew->pLeft = exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc);
+          pNew->pRight = exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc);
+        }
+        if( pzBuffer ){
+          *pzBuffer = zAlloc;
+        }
+      }else{
+        pNew->flags2 = 0;
+        if( !ExprHasAnyProperty(p, EP_TokenOnly) ){
+          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
+          pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
+        }
+      }
 
-    /* Remove the table entry from SQLite's internal schema and modify
-    ** the schema cookie.
-    */
-    if( IsVirtual(pTab) ){
-      sqlite3VdbeAddOp4(v, OP_VDestroy, iDb, 0, 0, pTab->zName, 0);
     }
-    sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
-    sqlite3ChangeCookie(pParse, iDb);
   }
-  sqliteViewResetAll(db, iDb);
-
-exit_drop_table:
-  sqlite3SrcListDelete(pName);
+  return pNew;
 }
 
 /*
-** This routine is called to create a new foreign key on the table
-** currently under construction.  pFromCol determines which columns
-** in the current table point to the foreign key.  If pFromCol==0 then
-** connect the key to the last column inserted.  pTo is the name of
-** the table referred to.  pToCol is a list of tables in the other
-** pTo table that the foreign key points to.  flags contains all
-** information about the conflict resolution algorithms specified
-** in the ON DELETE, ON UPDATE and ON INSERT clauses.
+** The following group of routines make deep copies of expressions,
+** expression lists, ID lists, and select statements.  The copies can
+** be deleted (by being passed to their respective ...Delete() routines)
+** without effecting the originals.
 **
-** An FKey structure is created and added to the table currently
-** under construction in the pParse->pNewTable field.  The new FKey
-** is not linked into db->aFKey at this point - that does not happen
-** until sqlite3EndTable().
+** The expression list, ID, and source lists return by sqlite3ExprListDup(),
+** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
+** by subsequent calls to sqlite*ListAppend() routines.
 **
-** The foreign key is set for IMMEDIATE processing.  A subsequent call
-** to sqlite3DeferForeignKey() might change this to DEFERRED.
+** Any tables that the SrcList might point to are not duplicated.
+**
+** The flags parameter contains a combination of the EXPRDUP_XXX flags.
+** If the EXPRDUP_REDUCE flag is set, then the structure returned is a
+** truncated version of the usual Expr structure that will be stored as
+** part of the in-memory representation of the database schema.
 */
-SQLITE_PRIVATE void sqlite3CreateForeignKey(
-  Parse *pParse,       /* Parsing context */
-  ExprList *pFromCol,  /* Columns in this table that point to other table */
-  Token *pTo,          /* Name of the other table */
-  ExprList *pToCol,    /* Columns in the other table */
-  int flags            /* Conflict resolution algorithms. */
-){
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-  FKey *pFKey = 0;
-  Table *p = pParse->pNewTable;
-  int nByte;
+SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3 *db, Expr *p, int flags){
+  return exprDup(db, p, flags, 0);
+}
+SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){
+  ExprList *pNew;
+  struct ExprList_item *pItem, *pOldItem;
   int i;
-  int nCol;
-  char *z;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
+  if( pNew==0 ) return 0;
+  pNew->iECursor = 0;
+  pNew->nExpr = pNew->nAlloc = p->nExpr;
+  pNew->a = pItem = sqlite3DbMallocRaw(db,  p->nExpr*sizeof(p->a[0]) );
+  if( pItem==0 ){
+    sqlite3DbFree(db, pNew);
+    return 0;
+  } 
+  pOldItem = p->a;
+  for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
+    Expr *pOldExpr = pOldItem->pExpr;
+    pItem->pExpr = sqlite3ExprDup(db, pOldExpr, flags);
+    pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pItem->zSpan = sqlite3DbStrDup(db, pOldItem->zSpan);
+    pItem->sortOrder = pOldItem->sortOrder;
+    pItem->done = 0;
+    pItem->iCol = pOldItem->iCol;
+    pItem->iAlias = pOldItem->iAlias;
+  }
+  return pNew;
+}
 
-  assert( pTo!=0 );
-  if( p==0 || pParse->nErr || IN_DECLARE_VTAB ) goto fk_end;
-  if( pFromCol==0 ){
-    int iCol = p->nCol-1;
-    if( iCol<0 ) goto fk_end;
-    if( pToCol && pToCol->nExpr!=1 ){
-      sqlite3ErrorMsg(pParse, "foreign key on %s"
-         " should reference only one column of table %T",
-         p->aCol[iCol].zName, pTo);
-      goto fk_end;
+/*
+** If cursors, triggers, views and subqueries are all omitted from
+** the build, then none of the following routines, except for 
+** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
+** called with a NULL argument.
+*/
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
+ || !defined(SQLITE_OMIT_SUBQUERY)
+SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){
+  SrcList *pNew;
+  int i;
+  int nByte;
+  if( p==0 ) return 0;
+  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
+  pNew = sqlite3DbMallocRaw(db, nByte );
+  if( pNew==0 ) return 0;
+  pNew->nSrc = pNew->nAlloc = p->nSrc;
+  for(i=0; i<p->nSrc; i++){
+    struct SrcList_item *pNewItem = &pNew->a[i];
+    struct SrcList_item *pOldItem = &p->a[i];
+    Table *pTab;
+    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
+    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
+    pNewItem->jointype = pOldItem->jointype;
+    pNewItem->iCursor = pOldItem->iCursor;
+    pNewItem->isPopulated = pOldItem->isPopulated;
+    pNewItem->zIndex = sqlite3DbStrDup(db, pOldItem->zIndex);
+    pNewItem->notIndexed = pOldItem->notIndexed;
+    pNewItem->pIndex = pOldItem->pIndex;
+    pTab = pNewItem->pTab = pOldItem->pTab;
+    if( pTab ){
+      pTab->nRef++;
     }
-    nCol = 1;
-  }else if( pToCol && pToCol->nExpr!=pFromCol->nExpr ){
-    sqlite3ErrorMsg(pParse,
-        "number of columns in foreign key does not match the number of "
-        "columns in the referenced table");
-    goto fk_end;
-  }else{
-    nCol = pFromCol->nExpr;
+    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags);
+    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn, flags);
+    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
+    pNewItem->colUsed = pOldItem->colUsed;
   }
-  nByte = sizeof(*pFKey) + nCol*sizeof(pFKey->aCol[0]) + pTo->n + 1;
-  if( pToCol ){
-    for(i=0; i<pToCol->nExpr; i++){
-      nByte += strlen(pToCol->a[i].zName) + 1;
-    }
+  return pNew;
+}
+SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
+  IdList *pNew;
+  int i;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
+  if( pNew==0 ) return 0;
+  pNew->nId = pNew->nAlloc = p->nId;
+  pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
+  if( pNew->a==0 ){
+    sqlite3DbFree(db, pNew);
+    return 0;
   }
-  pFKey = sqlite3DbMallocZero(pParse->db, nByte );
-  if( pFKey==0 ){
-    goto fk_end;
+  for(i=0; i<p->nId; i++){
+    struct IdList_item *pNewItem = &pNew->a[i];
+    struct IdList_item *pOldItem = &p->a[i];
+    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pNewItem->idx = pOldItem->idx;
   }
-  pFKey->pFrom = p;
-  pFKey->pNextFrom = p->pFKey;
-  z = (char*)&pFKey[1];
-  pFKey->aCol = (struct sColMap*)z;
-  z += sizeof(struct sColMap)*nCol;
-  pFKey->zTo = z;
-  memcpy(z, pTo->z, pTo->n);
-  z[pTo->n] = 0;
-  z += pTo->n+1;
-  pFKey->pNextTo = 0;
-  pFKey->nCol = nCol;
-  if( pFromCol==0 ){
-    pFKey->aCol[0].iFrom = p->nCol-1;
-  }else{
-    for(i=0; i<nCol; i++){
-      int j;
-      for(j=0; j<p->nCol; j++){
-        if( sqlite3StrICmp(p->aCol[j].zName, pFromCol->a[i].zName)==0 ){
-          pFKey->aCol[i].iFrom = j;
-          break;
-        }
-      }
-      if( j>=p->nCol ){
-        sqlite3ErrorMsg(pParse, 
-          "unknown column \"%s\" in foreign key definition", 
-          pFromCol->a[i].zName);
-        goto fk_end;
-      }
+  return pNew;
+}
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
+  Select *pNew;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
+  if( pNew==0 ) return 0;
+  pNew->pEList = sqlite3ExprListDup(db, p->pEList, flags);
+  pNew->pSrc = sqlite3SrcListDup(db, p->pSrc, flags);
+  pNew->pWhere = sqlite3ExprDup(db, p->pWhere, flags);
+  pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy, flags);
+  pNew->pHaving = sqlite3ExprDup(db, p->pHaving, flags);
+  pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, flags);
+  pNew->op = p->op;
+  pNew->pPrior = sqlite3SelectDup(db, p->pPrior, flags);
+  pNew->pLimit = sqlite3ExprDup(db, p->pLimit, flags);
+  pNew->pOffset = sqlite3ExprDup(db, p->pOffset, flags);
+  pNew->iLimit = 0;
+  pNew->iOffset = 0;
+  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
+  pNew->pRightmost = 0;
+  pNew->addrOpenEphm[0] = -1;
+  pNew->addrOpenEphm[1] = -1;
+  pNew->addrOpenEphm[2] = -1;
+  return pNew;
+}
+#else
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
+  assert( p==0 );
+  return 0;
+}
+#endif
+
+
+/*
+** Add a new element to the end of an expression list.  If pList is
+** initially NULL, then create a new expression list.
+**
+** If a memory allocation error occurs, the entire list is freed and
+** NULL is returned.  If non-NULL is returned, then it is guaranteed
+** that the new entry was successfully appended.
+*/
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pList,        /* List to which to append. Might be NULL */
+  Expr *pExpr             /* Expression to be appended. Might be NULL */
+){
+  sqlite3 *db = pParse->db;
+  if( pList==0 ){
+    pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
+    if( pList==0 ){
+      goto no_mem;
     }
+    assert( pList->nAlloc==0 );
   }
-  if( pToCol ){
-    for(i=0; i<nCol; i++){
-      int n = strlen(pToCol->a[i].zName);
-      pFKey->aCol[i].zCol = z;
-      memcpy(z, pToCol->a[i].zName, n);
-      z[n] = 0;
-      z += n+1;
+  if( pList->nAlloc<=pList->nExpr ){
+    struct ExprList_item *a;
+    int n = pList->nAlloc*2 + 4;
+    a = sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));
+    if( a==0 ){
+      goto no_mem;
     }
+    pList->a = a;
+    pList->nAlloc = sqlite3DbMallocSize(db, a)/sizeof(a[0]);
   }
-  pFKey->isDeferred = 0;
-  pFKey->deleteConf = flags & 0xff;
-  pFKey->updateConf = (flags >> 8 ) & 0xff;
-  pFKey->insertConf = (flags >> 16 ) & 0xff;
-
-  /* Link the foreign key to the table as the last step.
-  */
-  p->pFKey = pFKey;
-  pFKey = 0;
+  assert( pList->a!=0 );
+  if( 1 ){
+    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
+    memset(pItem, 0, sizeof(*pItem));
+    pItem->pExpr = pExpr;
+  }
+  return pList;
 
-fk_end:
-  sqlite3_free(pFKey);
-#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
-  sqlite3ExprListDelete(pFromCol);
-  sqlite3ExprListDelete(pToCol);
+no_mem:     
+  /* Avoid leaking memory if malloc has failed. */
+  sqlite3ExprDelete(db, pExpr);
+  sqlite3ExprListDelete(db, pList);
+  return 0;
 }
 
 /*
-** This routine is called when an INITIALLY IMMEDIATE or INITIALLY DEFERRED
-** clause is seen as part of a foreign key definition.  The isDeferred
-** parameter is 1 for INITIALLY DEFERRED and 0 for INITIALLY IMMEDIATE.
-** The behavior of the most recently created foreign key is adjusted
-** accordingly.
+** Set the ExprList.a[].zName element of the most recently added item
+** on the expression list.
+**
+** pList might be NULL following an OOM error.  But pName should never be
+** NULL.  If a memory allocation fails, the pParse->db->mallocFailed flag
+** is set.
 */
-SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse *pParse, int isDeferred){
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-  Table *pTab;
-  FKey *pFKey;
-  if( (pTab = pParse->pNewTable)==0 || (pFKey = pTab->pFKey)==0 ) return;
-  pFKey->isDeferred = isDeferred;
-#endif
+SQLITE_PRIVATE void sqlite3ExprListSetName(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pList,        /* List to which to add the span. */
+  Token *pName,           /* Name to be added */
+  int dequote             /* True to cause the name to be dequoted */
+){
+  assert( pList!=0 || pParse->db->mallocFailed!=0 );
+  if( pList ){
+    struct ExprList_item *pItem;
+    assert( pList->nExpr>0 );
+    pItem = &pList->a[pList->nExpr-1];
+    assert( pItem->zName==0 );
+    pItem->zName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n);
+    if( dequote && pItem->zName ) sqlite3Dequote(pItem->zName);
+  }
 }
 
 /*
-** Generate code that will erase and refill index *pIdx.  This is
-** used to initialize a newly created index or to recompute the
-** content of an index in response to a REINDEX command.
+** Set the ExprList.a[].zSpan element of the most recently added item
+** on the expression list.
 **
-** if memRootPage is not negative, it means that the index is newly
-** created.  The register specified by memRootPage contains the
-** root page number of the index.  If memRootPage is negative, then
-** the index already exists and must be cleared before being refilled and
-** the root page number of the index is taken from pIndex->tnum.
+** pList might be NULL following an OOM error.  But pSpan should never be
+** NULL.  If a memory allocation fails, the pParse->db->mallocFailed flag
+** is set.
 */
-static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
-  Table *pTab = pIndex->pTable;  /* The table that is indexed */
-  int iTab = pParse->nTab;       /* Btree cursor used for pTab */
-  int iIdx = pParse->nTab+1;     /* Btree cursor used for pIndex */
-  int addr1;                     /* Address of top of loop */
-  int tnum;                      /* Root page of index */
-  Vdbe *v;                       /* Generate code into this virtual machine */
-  KeyInfo *pKey;                 /* KeyInfo for index */
-  int regIdxKey;                 /* Registers containing the index key */
-  int regRecord;                 /* Register holding assemblied index record */
-  sqlite3 *db = pParse->db;      /* The database connection */
-  int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  if( sqlite3AuthCheck(pParse, SQLITE_REINDEX, pIndex->zName, 0,
-      db->aDb[iDb].zName ) ){
-    return;
+SQLITE_PRIVATE void sqlite3ExprListSetSpan(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pList,        /* List to which to add the span. */
+  ExprSpan *pSpan         /* The span to be added */
+){
+  sqlite3 *db = pParse->db;
+  assert( pList!=0 || db->mallocFailed!=0 );
+  if( pList ){
+    struct ExprList_item *pItem = &pList->a[pList->nExpr-1];
+    assert( pList->nExpr>0 );
+    assert( db->mallocFailed || pItem->pExpr==pSpan->pExpr );
+    sqlite3DbFree(db, pItem->zSpan);
+    pItem->zSpan = sqlite3DbStrNDup(db, (char*)pSpan->zStart,
+                                    (int)(pSpan->zEnd - pSpan->zStart));
   }
-#endif
+}
 
-  /* Require a write-lock on the table to perform this operation */
-  sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
+/*
+** If the expression list pEList contains more than iLimit elements,
+** leave an error message in pParse.
+*/
+SQLITE_PRIVATE void sqlite3ExprListCheckLength(
+  Parse *pParse,
+  ExprList *pEList,
+  const char *zObject
+){
+  int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN];
+  testcase( pEList && pEList->nExpr==mx );
+  testcase( pEList && pEList->nExpr==mx+1 );
+  if( pEList && pEList->nExpr>mx ){
+    sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
+  }
+}
 
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;
-  if( memRootPage>=0 ){
-    tnum = memRootPage;
-  }else{
-    tnum = pIndex->tnum;
-    sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
-  }
-  pKey = sqlite3IndexKeyinfo(pParse, pIndex);
-  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
-                    (char *)pKey, P4_KEYINFO_HANDOFF);
-  if( memRootPage>=0 ){
-    sqlite3VdbeChangeP5(v, 1);
-  }
-  sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
-  addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
-  regRecord = sqlite3GetTempReg(pParse);
-  regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
-  if( pIndex->onError!=OE_None ){
-    int j1, j2;
-    int regRowid;
-
-    regRowid = regIdxKey + pIndex->nColumn;
-    j1 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdxKey, 0, pIndex->nColumn);
-    j2 = sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx,
-                           0, regRowid, (char*)regRecord, P4_INT32);
-    sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort, 0,
-                    "indexed columns are not unique", P4_STATIC);
-    sqlite3VdbeJumpHere(v, j1);
-    sqlite3VdbeJumpHere(v, j2);
+/*
+** Delete an entire expression list.
+*/
+SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
+  int i;
+  struct ExprList_item *pItem;
+  if( pList==0 ) return;
+  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
+  assert( pList->nExpr<=pList->nAlloc );
+  for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
+    sqlite3ExprDelete(db, pItem->pExpr);
+    sqlite3DbFree(db, pItem->zName);
+    sqlite3DbFree(db, pItem->zSpan);
   }
-  sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
-  sqlite3ReleaseTempReg(pParse, regRecord);
-  sqlite3VdbeAddOp2(v, OP_Next, iTab, addr1+1);
-  sqlite3VdbeJumpHere(v, addr1);
-  sqlite3VdbeAddOp1(v, OP_Close, iTab);
-  sqlite3VdbeAddOp1(v, OP_Close, iIdx);
+  sqlite3DbFree(db, pList->a);
+  sqlite3DbFree(db, pList);
 }
 
 /*
-** Create a new index for an SQL table.  pName1.pName2 is the name of the index 
-** and pTblList is the name of the table that is to be indexed.  Both will 
-** be NULL for a primary key or an index that is created to satisfy a
-** UNIQUE constraint.  If pTable and pIndex are NULL, use pParse->pNewTable
-** as the table to be indexed.  pParse->pNewTable is a table that is
-** currently being constructed by a CREATE TABLE statement.
+** These routines are Walker callbacks.  Walker.u.pi is a pointer
+** to an integer.  These routines are checking an expression to see
+** if it is a constant.  Set *Walker.u.pi to 0 if the expression is
+** not constant.
+**
+** These callback routines are used to implement the following:
+**
+**     sqlite3ExprIsConstant()
+**     sqlite3ExprIsConstantNotJoin()
+**     sqlite3ExprIsConstantOrFunction()
 **
-** pList is a list of columns to be indexed.  pList will be NULL if this
-** is a primary key or unique-constraint on the most recent column added
-** to the table currently under construction.  
 */
-SQLITE_PRIVATE void sqlite3CreateIndex(
-  Parse *pParse,     /* All information about this parse */
-  Token *pName1,     /* First part of index name. May be NULL */
-  Token *pName2,     /* Second part of index name. May be NULL */
-  SrcList *pTblName, /* Table to index. Use pParse->pNewTable if 0 */
-  ExprList *pList,   /* A list of columns to be indexed */
-  int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
-  Token *pStart,     /* The CREATE token that begins this statement */
-  Token *pEnd,       /* The ")" that closes the CREATE INDEX statement */
-  int sortOrder,     /* Sort order of primary key when pList==NULL */
-  int ifNotExist     /* Omit error if index already exists */
-){
-  Table *pTab = 0;     /* Table to be indexed */
-  Index *pIndex = 0;   /* The index to be created */
-  char *zName = 0;     /* Name of the index */
-  int nName;           /* Number of characters in zName */
-  int i, j;
-  Token nullId;        /* Fake token for an empty ID list */
-  DbFixer sFix;        /* For assigning database names to pTable */
-  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
-  sqlite3 *db = pParse->db;
-  Db *pDb;             /* The specific table containing the indexed database */
-  int iDb;             /* Index of the database that is being written */
-  Token *pName = 0;    /* Unqualified name of the index to create */
-  struct ExprList_item *pListItem; /* For looping over pList */
-  int nCol;
-  int nExtra = 0;
-  char *zExtra;
+static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){
 
-  if( pParse->nErr || db->mallocFailed || IN_DECLARE_VTAB ){
-    goto exit_create_index;
+  /* If pWalker->u.i is 3 then any term of the expression that comes from
+  ** the ON or USING clauses of a join disqualifies the expression
+  ** from being considered constant. */
+  if( pWalker->u.i==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
+    pWalker->u.i = 0;
+    return WRC_Abort;
   }
 
-  /*
-  ** Find the table that is to be indexed.  Return early if not found.
-  */
-  if( pTblName!=0 ){
+  switch( pExpr->op ){
+    /* Consider functions to be constant if all their arguments are constant
+    ** and pWalker->u.i==2 */
+    case TK_FUNCTION:
+      if( pWalker->u.i==2 ) return 0;
+      /* Fall through */
+    case TK_ID:
+    case TK_COLUMN:
+    case TK_AGG_FUNCTION:
+    case TK_AGG_COLUMN:
+      testcase( pExpr->op==TK_ID );
+      testcase( pExpr->op==TK_COLUMN );
+      testcase( pExpr->op==TK_AGG_FUNCTION );
+      testcase( pExpr->op==TK_AGG_COLUMN );
+      pWalker->u.i = 0;
+      return WRC_Abort;
+    default:
+      testcase( pExpr->op==TK_SELECT ); /* selectNodeIsConstant will disallow */
+      testcase( pExpr->op==TK_EXISTS ); /* selectNodeIsConstant will disallow */
+      return WRC_Continue;
+  }
+}
+static int selectNodeIsConstant(Walker *pWalker, Select *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
+  pWalker->u.i = 0;
+  return WRC_Abort;
+}
+static int exprIsConst(Expr *p, int initFlag){
+  Walker w;
+  w.u.i = initFlag;
+  w.xExprCallback = exprNodeIsConstant;
+  w.xSelectCallback = selectNodeIsConstant;
+  sqlite3WalkExpr(&w, p);
+  return w.u.i;
+}
 
-    /* Use the two-part index name to determine the database 
-    ** to search for the table. 'Fix' the table name to this db
-    ** before looking up the table.
-    */
-    assert( pName1 && pName2 );
-    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
-    if( iDb<0 ) goto exit_create_index;
+/*
+** Walk an expression tree.  Return 1 if the expression is constant
+** and 0 if it involves variables or function calls.
+**
+** For the purposes of this function, a double-quoted string (ex: "abc")
+** is considered a variable but a single-quoted string (ex: 'abc') is
+** a constant.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr *p){
+  return exprIsConst(p, 1);
+}
 
-#ifndef SQLITE_OMIT_TEMPDB
-    /* If the index name was unqualified, check if the the table
-    ** is a temp table. If so, set the database to 1. Do not do this
-    ** if initialising a database schema.
-    */
-    if( !db->init.busy ){
-      pTab = sqlite3SrcListLookup(pParse, pTblName);
-      if( pName2 && pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
-        iDb = 1;
-      }
-    }
-#endif
+/*
+** Walk an expression tree.  Return 1 if the expression is constant
+** that does no originate from the ON or USING clauses of a join.
+** Return 0 if it involves variables or function calls or terms from
+** an ON or USING clause.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr *p){
+  return exprIsConst(p, 3);
+}
 
-    if( sqlite3FixInit(&sFix, pParse, iDb, "index", pName) &&
-        sqlite3FixSrcList(&sFix, pTblName)
-    ){
-      /* Because the parser constructs pTblName from a single identifier,
-      ** sqlite3FixSrcList can never fail. */
-      assert(0);
-    }
-    pTab = sqlite3LocateTable(pParse, 0, pTblName->a[0].zName, 
-        pTblName->a[0].zDatabase);
-    if( !pTab ) goto exit_create_index;
-    assert( db->aDb[iDb].pSchema==pTab->pSchema );
-  }else{
-    assert( pName==0 );
-    pTab = pParse->pNewTable;
-    if( !pTab ) goto exit_create_index;
-    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-  }
-  pDb = &db->aDb[iDb];
+/*
+** Walk an expression tree.  Return 1 if the expression is constant
+** or a function call with constant arguments.  Return and 0 if there
+** are any variables.
+**
+** For the purposes of this function, a double-quoted string (ex: "abc")
+** is considered a variable but a single-quoted string (ex: 'abc') is
+** a constant.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr *p){
+  return exprIsConst(p, 2);
+}
 
-  if( pTab==0 || pParse->nErr ) goto exit_create_index;
-  if( pTab->readOnly ){
-    sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
-    goto exit_create_index;
-  }
-#ifndef SQLITE_OMIT_VIEW
-  if( pTab->pSelect ){
-    sqlite3ErrorMsg(pParse, "views may not be indexed");
-    goto exit_create_index;
-  }
-#endif
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( IsVirtual(pTab) ){
-    sqlite3ErrorMsg(pParse, "virtual tables may not be indexed");
-    goto exit_create_index;
+/*
+** If the expression p codes a constant integer that is small enough
+** to fit in a 32-bit integer, return 1 and put the value of the integer
+** in *pValue.  If the expression is not an integer or if it is too big
+** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr *p, int *pValue){
+  int rc = 0;
+  if( p->flags & EP_IntValue ){
+    *pValue = p->u.iValue;
+    return 1;
   }
-#endif
-
-  /*
-  ** Find the name of the index.  Make sure there is not already another
-  ** index or table with the same name.  
-  **
-  ** Exception:  If we are reading the names of permanent indices from the
-  ** sqlite_master table (because some other process changed the schema) and
-  ** one of the index names collides with the name of a temporary table or
-  ** index, then we will continue to process this index.
-  **
-  ** If pName==0 it means that we are
-  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
-  ** own name.
-  */
-  if( pName ){
-    zName = sqlite3NameFromToken(db, pName);
-    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
-    if( zName==0 ) goto exit_create_index;
-    if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
-      goto exit_create_index;
+  switch( p->op ){
+    case TK_INTEGER: {
+      rc = sqlite3GetInt32(p->u.zToken, pValue);
+      assert( rc==0 );
+      break;
     }
-    if( !db->init.busy ){
-      if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
-      if( sqlite3FindTable(db, zName, 0)!=0 ){
-        sqlite3ErrorMsg(pParse, "there is already a table named %s", zName);
-        goto exit_create_index;
-      }
+    case TK_UPLUS: {
+      rc = sqlite3ExprIsInteger(p->pLeft, pValue);
+      break;
     }
-    if( sqlite3FindIndex(db, zName, pDb->zName)!=0 ){
-      if( !ifNotExist ){
-        sqlite3ErrorMsg(pParse, "index %s already exists", zName);
+    case TK_UMINUS: {
+      int v;
+      if( sqlite3ExprIsInteger(p->pLeft, &v) ){
+        *pValue = -v;
+        rc = 1;
       }
-      goto exit_create_index;
-    }
-  }else{
-    char zBuf[30];
-    int n;
-    Index *pLoop;
-    for(pLoop=pTab->pIndex, n=1; pLoop; pLoop=pLoop->pNext, n++){}
-    sqlite3_snprintf(sizeof(zBuf),zBuf,"_%d",n);
-    zName = 0;
-    sqlite3SetString(&zName, "sqlite_autoindex_", pTab->zName, zBuf, (char*)0);
-    if( zName==0 ){
-      db->mallocFailed = 1;
-      goto exit_create_index;
+      break;
     }
+    default: break;
   }
-
-  /* Check for authorization to create an index.
-  */
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  {
-    const char *zDb = pDb->zName;
-    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iDb), 0, zDb) ){
-      goto exit_create_index;
-    }
-    i = SQLITE_CREATE_INDEX;
-    if( !OMIT_TEMPDB && iDb==1 ) i = SQLITE_CREATE_TEMP_INDEX;
-    if( sqlite3AuthCheck(pParse, i, zName, pTab->zName, zDb) ){
-      goto exit_create_index;
-    }
+  if( rc ){
+    assert( ExprHasAnyProperty(p, EP_Reduced|EP_TokenOnly)
+               || (p->flags2 & EP2_MallocedToken)==0 );
+    p->op = TK_INTEGER;
+    p->flags |= EP_IntValue;
+    p->u.iValue = *pValue;
   }
-#endif
+  return rc;
+}
 
-  /* If pList==0, it means this routine was called to make a primary
-  ** key out of the last column added to the table under construction.
-  ** So create a fake list to simulate this.
-  */
-  if( pList==0 ){
-    nullId.z = (u8*)pTab->aCol[pTab->nCol-1].zName;
-    nullId.n = strlen((char*)nullId.z);
-    pList = sqlite3ExprListAppend(pParse, 0, 0, &nullId);
-    if( pList==0 ) goto exit_create_index;
-    pList->a[0].sortOrder = sortOrder;
-  }
+/*
+** Return TRUE if the given string is a row-id column name.
+*/
+SQLITE_PRIVATE int sqlite3IsRowid(const char *z){
+  if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
+  if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
+  if( sqlite3StrICmp(z, "OID")==0 ) return 1;
+  return 0;
+}
 
-  /* Figure out how many bytes of space are required to store explicitly
-  ** specified collation sequence names.
-  */
-  for(i=0; i<pList->nExpr; i++){
-    Expr *pExpr = pList->a[i].pExpr;
-    if( pExpr ){
-      nExtra += (1 + strlen(pExpr->pColl->zName));
-    }
+/*
+** Return true if we are able to the IN operator optimization on a
+** query of the form
+**
+**       x IN (SELECT ...)
+**
+** Where the SELECT... clause is as specified by the parameter to this
+** routine.
+**
+** The Select object passed in has already been preprocessed and no
+** errors have been found.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+static int isCandidateForInOpt(Select *p){
+  SrcList *pSrc;
+  ExprList *pEList;
+  Table *pTab;
+  if( p==0 ) return 0;                   /* right-hand side of IN is SELECT */
+  if( p->pPrior ) return 0;              /* Not a compound SELECT */
+  if( p->selFlags & (SF_Distinct|SF_Aggregate) ){
+    testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct );
+    testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate );
+    return 0; /* No DISTINCT keyword and no aggregate functions */
   }
+  assert( p->pGroupBy==0 );              /* Has no GROUP BY clause */
+  if( p->pLimit ) return 0;              /* Has no LIMIT clause */
+  assert( p->pOffset==0 );               /* No LIMIT means no OFFSET */
+  if( p->pWhere ) return 0;              /* Has no WHERE clause */
+  pSrc = p->pSrc;
+  assert( pSrc!=0 );
+  if( pSrc->nSrc!=1 ) return 0;          /* Single term in FROM clause */
+  if( pSrc->a[0].pSelect ) return 0;     /* FROM is not a subquery or view */
+  pTab = pSrc->a[0].pTab;
+  if( NEVER(pTab==0) ) return 0;
+  assert( pTab->pSelect==0 );            /* FROM clause is not a view */
+  if( IsVirtual(pTab) ) return 0;        /* FROM clause not a virtual table */
+  pEList = p->pEList;
+  if( pEList->nExpr!=1 ) return 0;       /* One column in the result set */
+  if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
+  return 1;
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
 
-  /* 
-  ** Allocate the index structure. 
-  */
-  nName = strlen(zName);
-  nCol = pList->nExpr;
-  pIndex = sqlite3DbMallocZero(db, 
-      sizeof(Index) +              /* Index structure  */
-      sizeof(int)*nCol +           /* Index.aiColumn   */
-      sizeof(int)*(nCol+1) +       /* Index.aiRowEst   */
-      sizeof(char *)*nCol +        /* Index.azColl     */
-      sizeof(u8)*nCol +            /* Index.aSortOrder */
-      nName + 1 +                  /* Index.zName      */
-      nExtra                       /* Collation sequence names */
-  );
-  if( db->mallocFailed ){
-    goto exit_create_index;
-  }
-  pIndex->azColl = (char**)(&pIndex[1]);
-  pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
-  pIndex->aiRowEst = (unsigned *)(&pIndex->aiColumn[nCol]);
-  pIndex->aSortOrder = (u8 *)(&pIndex->aiRowEst[nCol+1]);
-  pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
-  zExtra = (char *)(&pIndex->zName[nName+1]);
-  memcpy(pIndex->zName, zName, nName+1);
-  pIndex->pTable = pTab;
-  pIndex->nColumn = pList->nExpr;
-  pIndex->onError = onError;
-  pIndex->autoIndex = pName==0;
-  pIndex->pSchema = db->aDb[iDb].pSchema;
+/*
+** This function is used by the implementation of the IN (...) operator.
+** It's job is to find or create a b-tree structure that may be used
+** either to test for membership of the (...) set or to iterate through
+** its members, skipping duplicates.
+**
+** The index of the cursor opened on the b-tree (database table, database index 
+** or ephermal table) is stored in pX->iTable before this function returns.
+** The returned value of this function indicates the b-tree type, as follows:
+**
+**   IN_INDEX_ROWID - The cursor was opened on a database table.
+**   IN_INDEX_INDEX - The cursor was opened on a database index.
+**   IN_INDEX_EPH -   The cursor was opened on a specially created and
+**                    populated epheremal table.
+**
+** An existing b-tree may only be used if the SELECT is of the simple
+** form:
+**
+**     SELECT <column> FROM <table>
+**
+** If the prNotFound parameter is 0, then the b-tree will be used to iterate
+** through the set members, skipping any duplicates. In this case an
+** epheremal table must be used unless the selected <column> is guaranteed
+** to be unique - either because it is an INTEGER PRIMARY KEY or it
+** has a UNIQUE constraint or UNIQUE index.
+**
+** If the prNotFound parameter is not 0, then the b-tree will be used 
+** for fast set membership tests. In this case an epheremal table must 
+** be used unless <column> is an INTEGER PRIMARY KEY or an index can 
+** be found with <column> as its left-most column.
+**
+** When the b-tree is being used for membership tests, the calling function
+** needs to know whether or not the structure contains an SQL NULL 
+** value in order to correctly evaluate expressions like "X IN (Y, Z)".
+** If there is a chance that the b-tree might contain a NULL value at
+** runtime, then a register is allocated and the register number written
+** to *prNotFound. If there is no chance that the b-tree contains a
+** NULL value, then *prNotFound is left unchanged.
+**
+** If a register is allocated and its location stored in *prNotFound, then
+** its initial value is NULL. If the b-tree does not remain constant
+** for the duration of the query (i.e. the SELECT that generates the b-tree
+** is a correlated subquery) then the value of the allocated register is
+** reset to NULL each time the b-tree is repopulated. This allows the
+** caller to use vdbe code equivalent to the following:
+**
+**   if( register==NULL ){
+**     has_null = <test if data structure contains null>
+**     register = 1
+**   }
+**
+** in order to avoid running the <test if data structure contains null>
+** test more often than is necessary.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
+  Select *p;                            /* SELECT to the right of IN operator */
+  int eType = 0;                        /* Type of RHS table. IN_INDEX_* */
+  int iTab = pParse->nTab++;            /* Cursor of the RHS table */
+  int mustBeUnique = (prNotFound==0);   /* True if RHS must be unique */
+
+  /* Check to see if an existing table or index can be used to
+  ** satisfy the query.  This is preferable to generating a new 
+  ** ephemeral table.
+  */
+  p = (ExprHasProperty(pX, EP_xIsSelect) ? pX->x.pSelect : 0);
+  if( ALWAYS(pParse->nErr==0) && isCandidateForInOpt(p) ){
+    sqlite3 *db = pParse->db;              /* Database connection */
+    Expr *pExpr = p->pEList->a[0].pExpr;   /* Expression <column> */
+    int iCol = pExpr->iColumn;             /* Index of column <column> */
+    Vdbe *v = sqlite3GetVdbe(pParse);      /* Virtual machine being coded */
+    Table *pTab = p->pSrc->a[0].pTab;      /* Table <table>. */
+    int iDb;                               /* Database idx for pTab */
+   
+    /* Code an OP_VerifyCookie and OP_TableLock for <table>. */
+    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    sqlite3CodeVerifySchema(pParse, iDb);
+    sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
 
-  /* Check to see if we should honor DESC requests on index columns
-  */
-  if( pDb->pSchema->file_format>=4 ){
-    sortOrderMask = -1;   /* Honor DESC */
-  }else{
-    sortOrderMask = 0;    /* Ignore DESC */
-  }
+    /* This function is only called from two places. In both cases the vdbe
+    ** has already been allocated. So assume sqlite3GetVdbe() is always
+    ** successful here.
+    */
+    assert(v);
+    if( iCol<0 ){
+      int iMem = ++pParse->nMem;
+      int iAddr;
 
-  /* Scan the names of the columns of the table to be indexed and
-  ** load the column indices into the Index structure.  Report an error
-  ** if any column is not found.
-  */
-  for(i=0, pListItem=pList->a; i<pList->nExpr; i++, pListItem++){
-    const char *zColName = pListItem->zName;
-    Column *pTabCol;
-    int requestedSortOrder;
-    char *zColl;                   /* Collation sequence name */
+      iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
 
-    for(j=0, pTabCol=pTab->aCol; j<pTab->nCol; j++, pTabCol++){
-      if( sqlite3StrICmp(zColName, pTabCol->zName)==0 ) break;
-    }
-    if( j>=pTab->nCol ){
-      sqlite3ErrorMsg(pParse, "table %s has no column named %s",
-        pTab->zName, zColName);
-      goto exit_create_index;
-    }
-    /* TODO:  Add a test to make sure that the same column is not named
-    ** more than once within the same index.  Only the first instance of
-    ** the column will ever be used by the optimizer.  Note that using the
-    ** same column more than once cannot be an error because that would 
-    ** break backwards compatibility - it needs to be a warning.
-    */
-    pIndex->aiColumn[i] = j;
-    if( pListItem->pExpr ){
-      assert( pListItem->pExpr->pColl );
-      zColl = zExtra;
-      sqlite3_snprintf(nExtra, zExtra, "%s", pListItem->pExpr->pColl->zName);
-      zExtra += (strlen(zColl) + 1);
+      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
+      eType = IN_INDEX_ROWID;
+
+      sqlite3VdbeJumpHere(v, iAddr);
     }else{
-      zColl = pTab->aCol[j].zColl;
-      if( !zColl ){
-        zColl = db->pDfltColl->zName;
-      }
-    }
-    if( !db->init.busy && !sqlite3LocateCollSeq(pParse, zColl, -1) ){
-      goto exit_create_index;
-    }
-    pIndex->azColl[i] = zColl;
-    requestedSortOrder = pListItem->sortOrder & sortOrderMask;
-    pIndex->aSortOrder[i] = requestedSortOrder;
-  }
-  sqlite3DefaultRowEst(pIndex);
+      Index *pIdx;                         /* Iterator variable */
 
-  if( pTab==pParse->pNewTable ){
-    /* This routine has been called to create an automatic index as a
-    ** result of a PRIMARY KEY or UNIQUE clause on a column definition, or
-    ** a PRIMARY KEY or UNIQUE clause following the column definitions.
-    ** i.e. one of:
-    **
-    ** CREATE TABLE t(x PRIMARY KEY, y);
-    ** CREATE TABLE t(x, y, UNIQUE(x, y));
-    **
-    ** Either way, check to see if the table already has such an index. If
-    ** so, don't bother creating this one. This only applies to
-    ** automatically created indices. Users can do as they wish with
-    ** explicit indices.
-    */
-    Index *pIdx;
-    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-      int k;
-      assert( pIdx->onError!=OE_None );
-      assert( pIdx->autoIndex );
-      assert( pIndex->onError!=OE_None );
+      /* The collation sequence used by the comparison. If an index is to
+      ** be used in place of a temp-table, it must be ordered according
+      ** to this collation sequence.  */
+      CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
 
-      if( pIdx->nColumn!=pIndex->nColumn ) continue;
-      for(k=0; k<pIdx->nColumn; k++){
-        const char *z1 = pIdx->azColl[k];
-        const char *z2 = pIndex->azColl[k];
-        if( pIdx->aiColumn[k]!=pIndex->aiColumn[k] ) break;
-        if( pIdx->aSortOrder[k]!=pIndex->aSortOrder[k] ) break;
-        if( z1!=z2 && sqlite3StrICmp(z1, z2) ) break;
-      }
-      if( k==pIdx->nColumn ){
-        if( pIdx->onError!=pIndex->onError ){
-          /* This constraint creates the same index as a previous
-          ** constraint specified somewhere in the CREATE TABLE statement.
-          ** However the ON CONFLICT clauses are different. If both this 
-          ** constraint and the previous equivalent constraint have explicit
-          ** ON CONFLICT clauses this is an error. Otherwise, use the
-          ** explicitly specified behaviour for the index.
-          */
-          if( !(pIdx->onError==OE_Default || pIndex->onError==OE_Default) ){
-            sqlite3ErrorMsg(pParse, 
-                "conflicting ON CONFLICT clauses specified", 0);
-          }
-          if( pIdx->onError==OE_Default ){
-            pIdx->onError = pIndex->onError;
+      /* Check that the affinity that will be used to perform the 
+      ** comparison is the same as the affinity of the column. If
+      ** it is not, it is not possible to use any index.
+      */
+      char aff = comparisonAffinity(pX);
+      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
+
+      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
+        if( (pIdx->aiColumn[0]==iCol)
+         && sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], 0)==pReq
+         && (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
+        ){
+          int iMem = ++pParse->nMem;
+          int iAddr;
+          char *pKey;
+  
+          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
+          iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
+          sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
+  
+          sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
+                               pKey,P4_KEYINFO_HANDOFF);
+          VdbeComment((v, "%s", pIdx->zName));
+          eType = IN_INDEX_INDEX;
+
+          sqlite3VdbeJumpHere(v, iAddr);
+          if( prNotFound && !pTab->aCol[iCol].notNull ){
+            *prNotFound = ++pParse->nMem;
           }
         }
-        goto exit_create_index;
       }
     }
   }
 
-  /* Link the new Index structure to its table and to the other
-  ** in-memory database structures. 
-  */
-  if( db->init.busy ){
-    Index *p;
-    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 
-                         pIndex->zName, strlen(pIndex->zName)+1, pIndex);
-    if( p ){
-      assert( p==pIndex );  /* Malloc must have failed */
-      db->mallocFailed = 1;
-      goto exit_create_index;
-    }
-    db->flags |= SQLITE_InternChanges;
-    if( pTblName!=0 ){
-      pIndex->tnum = db->init.newTnum;
+  if( eType==0 ){
+    /* Could not found an existing able or index to use as the RHS b-tree.
+    ** We will have to generate an ephemeral table to do the job.
+    */
+    int rMayHaveNull = 0;
+    eType = IN_INDEX_EPH;
+    if( prNotFound ){
+      *prNotFound = rMayHaveNull = ++pParse->nMem;
+    }else if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
+      eType = IN_INDEX_ROWID;
     }
+    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
+  }else{
+    pX->iTable = iTab;
   }
+  return eType;
+}
+#endif
 
-  /* If the db->init.busy is 0 then create the index on disk.  This
-  ** involves writing the index into the master table and filling in the
-  ** index with the current table contents.
-  **
-  ** The db->init.busy is 0 when the user first enters a CREATE INDEX 
-  ** command.  db->init.busy is 1 when a database is opened and 
-  ** CREATE INDEX statements are read out of the master table.  In
-  ** the latter case the index already exists on disk, which is why
-  ** we don't want to recreate it.
-  **
-  ** If pTblName==0 it means this index is generated as a primary key
-  ** or UNIQUE constraint of a CREATE TABLE statement.  Since the table
-  ** has just been created, it contains no data and the index initialization
-  ** step can be skipped.
-  */
-  else if( db->init.busy==0 ){
-    Vdbe *v;
-    char *zStmt;
-    int iMem = ++pParse->nMem;
+/*
+** Generate code for scalar subqueries used as an expression
+** and IN operators.  Examples:
+**
+**     (SELECT a FROM b)          -- subquery
+**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
+**     x IN (4,5,11)              -- IN operator with list on right-hand side
+**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
+**
+** The pExpr parameter describes the expression that contains the IN
+** operator or subquery.
+**
+** If parameter isRowid is non-zero, then expression pExpr is guaranteed
+** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference
+** to some integer key column of a table B-Tree. In this case, use an
+** intkey B-Tree to store the set of IN(...) values instead of the usual
+** (slower) variable length keys B-Tree.
+**
+** If rMayHaveNull is non-zero, that means that the operation is an IN
+** (not a SELECT or EXISTS) and that the RHS might contains NULLs.
+** Furthermore, the IN is in a WHERE clause and that we really want
+** to iterate over the RHS of the IN operator in order to quickly locate
+** all corresponding LHS elements.  All this routine does is initialize
+** the register given by rMayHaveNull to NULL.  Calling routines will take
+** care of changing this register value to non-NULL if the RHS is NULL-free.
+**
+** If rMayHaveNull is zero, that means that the subquery is being used
+** for membership testing only.  There is no need to initialize any
+** registers to indicate the presense or absence of NULLs on the RHS.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+SQLITE_PRIVATE void sqlite3CodeSubselect(
+  Parse *pParse,          /* Parsing context */
+  Expr *pExpr,            /* The IN, SELECT, or EXISTS operator */
+  int rMayHaveNull,       /* Register that records whether NULLs exist in RHS */
+  int isRowid             /* If true, LHS of IN operator is a rowid */
+){
+  int testAddr = 0;                       /* One-time test address */
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( NEVER(v==0) ) return;
+  sqlite3ExprCachePush(pParse);
 
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) goto exit_create_index;
+  /* This code must be run in its entirety every time it is encountered
+  ** if any of the following is true:
+  **
+  **    *  The right-hand side is a correlated subquery
+  **    *  The right-hand side is an expression list containing variables
+  **    *  We are inside a trigger
+  **
+  ** If all of the above are false, then we can run this code just once
+  ** save the results, and reuse the same result on subsequent invocations.
+  */
+  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->pTriggerTab ){
+    int mem = ++pParse->nMem;
+    sqlite3VdbeAddOp1(v, OP_If, mem);
+    testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
+    assert( testAddr>0 || pParse->db->mallocFailed );
+  }
 
+  switch( pExpr->op ){
+    case TK_IN: {
+      char affinity;
+      KeyInfo keyInfo;
+      int addr;        /* Address of OP_OpenEphemeral instruction */
+      Expr *pLeft = pExpr->pLeft;
 
-    /* Create the rootpage for the index
-    */
-    sqlite3BeginWriteOperation(pParse, 1, iDb);
-    sqlite3VdbeAddOp2(v, OP_CreateIndex, iDb, iMem);
+      if( rMayHaveNull ){
+        sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
+      }
 
-    /* Gather the complete text of the CREATE INDEX statement into
-    ** the zStmt variable
-    */
-    if( pStart && pEnd ){
-      /* A named index with an explicit CREATE INDEX statement */
-      zStmt = sqlite3MPrintf(db, "CREATE%s INDEX %.*s",
-        onError==OE_None ? "" : " UNIQUE",
-        pEnd->z - pName->z + 1,
-        pName->z);
-    }else{
-      /* An automatic index created by a PRIMARY KEY or UNIQUE constraint */
-      /* zStmt = sqlite3MPrintf(""); */
-      zStmt = 0;
-    }
+      affinity = sqlite3ExprAffinity(pLeft);
 
-    /* Add an entry in sqlite_master for this index
-    */
-    sqlite3NestedParse(pParse, 
-        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,#%d,%Q);",
-        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
-        pIndex->zName,
-        pTab->zName,
-        iMem,
-        zStmt
-    );
-    sqlite3_free(zStmt);
+      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
+      ** expression it is handled the same way. A virtual table is 
+      ** filled with single-field index keys representing the results
+      ** from the SELECT or the <exprlist>.
+      **
+      ** If the 'x' expression is a column value, or the SELECT...
+      ** statement returns a column value, then the affinity of that
+      ** column is used to build the index keys. If both 'x' and the
+      ** SELECT... statement are columns, then numeric affinity is used
+      ** if either column has NUMERIC or INTEGER affinity. If neither
+      ** 'x' nor the SELECT... statement are columns, then numeric affinity
+      ** is used.
+      */
+      pExpr->iTable = pParse->nTab++;
+      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
+      memset(&keyInfo, 0, sizeof(keyInfo));
+      keyInfo.nField = 1;
 
-    /* Fill the index with data and reparse the schema. Code an OP_Expire
-    ** to invalidate all pre-compiled statements.
-    */
-    if( pTblName ){
-      sqlite3RefillIndex(pParse, pIndex, iMem);
-      sqlite3ChangeCookie(pParse, iDb);
-      sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0,
-         sqlite3MPrintf(db, "name='%q'", pIndex->zName), P4_DYNAMIC);
-      sqlite3VdbeAddOp1(v, OP_Expire, 0);
+      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+        /* Case 1:     expr IN (SELECT ...)
+        **
+        ** Generate code to write the results of the select into the temporary
+        ** table allocated and opened above.
+        */
+        SelectDest dest;
+        ExprList *pEList;
+
+        assert( !isRowid );
+        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
+        dest.affinity = (u8)affinity;
+        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
+        if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
+          return;
+        }
+        pEList = pExpr->x.pSelect->pEList;
+        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 
+          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
+              pEList->a[0].pExpr);
+        }
+      }else if( pExpr->x.pList!=0 ){
+        /* Case 2:     expr IN (exprlist)
+        **
+        ** For each expression, build an index key from the evaluation and
+        ** store it in the temporary table. If <expr> is a column, then use
+        ** that columns affinity when building index keys. If <expr> is not
+        ** a column, use numeric affinity.
+        */
+        int i;
+        ExprList *pList = pExpr->x.pList;
+        struct ExprList_item *pItem;
+        int r1, r2, r3;
+
+        if( !affinity ){
+          affinity = SQLITE_AFF_NONE;
+        }
+        keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+
+        /* Loop through each expression in <exprlist>. */
+        r1 = sqlite3GetTempReg(pParse);
+        r2 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
+        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
+          Expr *pE2 = pItem->pExpr;
+
+          /* If the expression is not constant then we will need to
+          ** disable the test that was generated above that makes sure
+          ** this code only executes once.  Because for a non-constant
+          ** expression we need to rerun this code each time.
+          */
+          if( testAddr && !sqlite3ExprIsConstant(pE2) ){
+            sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
+            testAddr = 0;
+          }
+
+          /* Evaluate the expression and insert it into the temp table */
+          r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
+          if( isRowid ){
+            sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, sqlite3VdbeCurrentAddr(v)+2);
+            sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
+          }else{
+            sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
+            sqlite3ExprCacheAffinityChange(pParse, r3, 1);
+            sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
+          }
+        }
+        sqlite3ReleaseTempReg(pParse, r1);
+        sqlite3ReleaseTempReg(pParse, r2);
+      }
+      if( !isRowid ){
+        sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
+      }
+      break;
     }
-  }
 
-  /* When adding an index to the list of indices for a table, make
-  ** sure all indices labeled OE_Replace come after all those labeled
-  ** OE_Ignore.  This is necessary for the correct operation of UPDATE
-  ** and INSERT.
-  */
-  if( db->init.busy || pTblName==0 ){
-    if( onError!=OE_Replace || pTab->pIndex==0
-         || pTab->pIndex->onError==OE_Replace){
-      pIndex->pNext = pTab->pIndex;
-      pTab->pIndex = pIndex;
-    }else{
-      Index *pOther = pTab->pIndex;
-      while( pOther->pNext && pOther->pNext->onError!=OE_Replace ){
-        pOther = pOther->pNext;
+    case TK_EXISTS:
+    case TK_SELECT:
+    default: {
+      /* If this has to be a scalar SELECT.  Generate code to put the
+      ** value of this select in a memory cell and record the number
+      ** of the memory cell in iColumn.  If this is an EXISTS, write
+      ** an integer 0 (not exists) or 1 (exists) into a memory cell
+      ** and record that memory cell in iColumn.
+      */
+      static const Token one = { "1", 1 };  /* Token for literal value 1 */
+      Select *pSel;                         /* SELECT statement to encode */
+      SelectDest dest;                      /* How to deal with SELECt result */
+
+      testcase( pExpr->op==TK_EXISTS );
+      testcase( pExpr->op==TK_SELECT );
+      assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
+
+      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
+      pSel = pExpr->x.pSelect;
+      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
+      if( pExpr->op==TK_SELECT ){
+        dest.eDest = SRT_Mem;
+        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
+        VdbeComment((v, "Init subquery result"));
+      }else{
+        dest.eDest = SRT_Exists;
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
+        VdbeComment((v, "Init EXISTS result"));
       }
-      pIndex->pNext = pOther->pNext;
-      pOther->pNext = pIndex;
+      sqlite3ExprDelete(pParse->db, pSel->pLimit);
+      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
+      if( sqlite3Select(pParse, pSel, &dest) ){
+        return;
+      }
+      pExpr->iColumn = (i16)dest.iParm;
+      ExprSetIrreducible(pExpr);
+      break;
     }
-    pIndex = 0;
   }
 
-  /* Clean up before exiting */
-exit_create_index:
-  if( pIndex ){
-    freeIndex(pIndex);
+  if( testAddr ){
+    sqlite3VdbeJumpHere(v, testAddr-1);
   }
-  sqlite3ExprListDelete(pList);
-  sqlite3SrcListDelete(pTblName);
-  sqlite3_free(zName);
+  sqlite3ExprCachePop(pParse, 1);
+
   return;
 }
+#endif /* SQLITE_OMIT_SUBQUERY */
 
 /*
-** Generate code to make sure the file format number is at least minFormat.
-** The generated code will increase the file format number if necessary.
+** Duplicate an 8-byte value
 */
-SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
-  Vdbe *v;
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    int r1 = sqlite3GetTempReg(pParse);
-    int r2 = sqlite3GetTempReg(pParse);
-    int j1;
-    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, 1);
-    sqlite3VdbeUsesBtree(v, iDb);
-    sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
-    j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
-    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 1, r2);
-    sqlite3VdbeJumpHere(v, j1);
-    sqlite3ReleaseTempReg(pParse, r1);
-    sqlite3ReleaseTempReg(pParse, r2);
+static char *dup8bytes(Vdbe *v, const char *in){
+  char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
+  if( out ){
+    memcpy(out, in, 8);
   }
+  return out;
 }
 
 /*
-** Fill the Index.aiRowEst[] array with default information - information
-** to be used when we have not run the ANALYZE command.
-**
-** aiRowEst[0] is suppose to contain the number of elements in the index.
-** Since we do not know, guess 1 million.  aiRowEst[1] is an estimate of the
-** number of rows in the table that match any particular value of the
-** first column of the index.  aiRowEst[2] is an estimate of the number
-** of rows that match any particular combiniation of the first 2 columns
-** of the index.  And so forth.  It must always be the case that
-*
-**           aiRowEst[N]<=aiRowEst[N-1]
-**           aiRowEst[N]>=1
+** Generate an instruction that will put the floating point
+** value described by z[0..n-1] into register iMem.
 **
-** Apart from that, we have little to go on besides intuition as to
-** how aiRowEst[] should be initialized.  The numbers generated here
-** are based on typical values found in actual indices.
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
 */
-SQLITE_PRIVATE void sqlite3DefaultRowEst(Index *pIdx){
-  unsigned *a = pIdx->aiRowEst;
-  int i;
-  assert( a!=0 );
-  a[0] = 1000000;
-  for(i=pIdx->nColumn; i>=5; i--){
-    a[i] = 5;
+static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
+  if( ALWAYS(z!=0) ){
+    double value;
+    char *zV;
+    sqlite3AtoF(z, &value);
+    assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */
+    if( negateFlag ) value = -value;
+    zV = dup8bytes(v, (char*)&value);
+    sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
   }
-  while( i>=1 ){
-    a[i] = 11 - i;
-    i--;
+}
+
+
+/*
+** Generate an instruction that will put the integer describe by
+** text z[0..n-1] into register iMem.
+**
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
+*/
+static void codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
+  if( pExpr->flags & EP_IntValue ){
+    int i = pExpr->u.iValue;
+    if( negFlag ) i = -i;
+    sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
+  }else{
+    const char *z = pExpr->u.zToken;
+    assert( z!=0 );
+    if( sqlite3FitsIn64Bits(z, negFlag) ){
+      i64 value;
+      char *zV;
+      sqlite3Atoi64(z, &value);
+      if( negFlag ) value = -value;
+      zV = dup8bytes(v, (char*)&value);
+      sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
+    }else{
+      codeReal(v, z, negFlag, iMem);
+    }
   }
-  if( pIdx->onError!=OE_None ){
-    a[pIdx->nColumn] = 1;
+}
+
+/*
+** Clear a cache entry.
+*/
+static void cacheEntryClear(Parse *pParse, struct yColCache *p){
+  if( p->tempReg ){
+    if( pParse->nTempReg<ArraySize(pParse->aTempReg) ){
+      pParse->aTempReg[pParse->nTempReg++] = p->iReg;
+    }
+    p->tempReg = 0;
   }
 }
 
+
 /*
-** This routine will drop an existing named index.  This routine
-** implements the DROP INDEX statement.
+** Record in the column cache that a particular column from a
+** particular table is stored in a particular register.
 */
-SQLITE_PRIVATE void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
-  Index *pIndex;
-  Vdbe *v;
-  sqlite3 *db = pParse->db;
-  int iDb;
+SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse *pParse, int iTab, int iCol, int iReg){
+  int i;
+  int minLru;
+  int idxLru;
+  struct yColCache *p;
 
-  if( pParse->nErr || db->mallocFailed ){
-    goto exit_drop_index;
-  }
-  assert( pName->nSrc==1 );
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-    goto exit_drop_index;
-  }
-  pIndex = sqlite3FindIndex(db, pName->a[0].zName, pName->a[0].zDatabase);
-  if( pIndex==0 ){
-    if( !ifExists ){
-      sqlite3ErrorMsg(pParse, "no such index: %S", pName, 0);
+  assert( iReg>0 );  /* Register numbers are always positive */
+  assert( iCol>=-1 && iCol<32768 );  /* Finite column numbers */
+
+  /* First replace any existing entry */
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg && p->iTable==iTab && p->iColumn==iCol ){
+      cacheEntryClear(pParse, p);
+      p->iLevel = pParse->iCacheLevel;
+      p->iReg = iReg;
+      p->affChange = 0;
+      p->lru = pParse->iCacheCnt++;
+      return;
     }
-    pParse->checkSchema = 1;
-    goto exit_drop_index;
-  }
-  if( pIndex->autoIndex ){
-    sqlite3ErrorMsg(pParse, "index associated with UNIQUE "
-      "or PRIMARY KEY constraint cannot be dropped", 0);
-    goto exit_drop_index;
   }
-  iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  {
-    int code = SQLITE_DROP_INDEX;
-    Table *pTab = pIndex->pTable;
-    const char *zDb = db->aDb[iDb].zName;
-    const char *zTab = SCHEMA_TABLE(iDb);
-    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
-      goto exit_drop_index;
-    }
-    if( !OMIT_TEMPDB && iDb ) code = SQLITE_DROP_TEMP_INDEX;
-    if( sqlite3AuthCheck(pParse, code, pIndex->zName, pTab->zName, zDb) ){
-      goto exit_drop_index;
+
+  /* Find an empty slot and replace it */
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg==0 ){
+      p->iLevel = pParse->iCacheLevel;
+      p->iTable = iTab;
+      p->iColumn = iCol;
+      p->iReg = iReg;
+      p->affChange = 0;
+      p->tempReg = 0;
+      p->lru = pParse->iCacheCnt++;
+      return;
     }
   }
-#endif
 
-  /* Generate code to remove the index and from the master table */
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3BeginWriteOperation(pParse, 1, iDb);
-    sqlite3NestedParse(pParse,
-       "DELETE FROM %Q.%s WHERE name=%Q",
-       db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
-       pIndex->zName
-    );
-    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
-      sqlite3NestedParse(pParse,
-        "DELETE FROM %Q.sqlite_stat1 WHERE idx=%Q",
-        db->aDb[iDb].zName, pIndex->zName
-      );
+  /* Replace the last recently used */
+  minLru = 0x7fffffff;
+  idxLru = -1;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->lru<minLru ){
+      idxLru = i;
+      minLru = p->lru;
     }
-    sqlite3ChangeCookie(pParse, iDb);
-    destroyRootPage(pParse, pIndex->tnum, iDb);
-    sqlite3VdbeAddOp4(v, OP_DropIndex, iDb, 0, 0, pIndex->zName, 0);
   }
-
-exit_drop_index:
-  sqlite3SrcListDelete(pName);
+  if( ALWAYS(idxLru>=0) ){
+    p = &pParse->aColCache[idxLru];
+    p->iLevel = pParse->iCacheLevel;
+    p->iTable = iTab;
+    p->iColumn = iCol;
+    p->iReg = iReg;
+    p->affChange = 0;
+    p->tempReg = 0;
+    p->lru = pParse->iCacheCnt++;
+    return;
+  }
 }
 
 /*
-** pArray is a pointer to an array of objects.  Each object in the
-** array is szEntry bytes in size.  This routine allocates a new
-** object on the end of the array.
-**
-** *pnEntry is the number of entries already in use.  *pnAlloc is
-** the previously allocated size of the array.  initSize is the
-** suggested initial array size allocation.
-**
-** The index of the new entry is returned in *pIdx.
-**
-** This routine returns a pointer to the array of objects.  This
-** might be the same as the pArray parameter or it might be a different
-** pointer if the array was resized.
+** Indicate that a register is being overwritten.  Purge the register
+** from the column cache.
 */
-SQLITE_PRIVATE void *sqlite3ArrayAllocate(
-  sqlite3 *db,      /* Connection to notify of malloc failures */
-  void *pArray,     /* Array of objects.  Might be reallocated */
-  int szEntry,      /* Size of each object in the array */
-  int initSize,     /* Suggested initial allocation, in elements */
-  int *pnEntry,     /* Number of objects currently in use */
-  int *pnAlloc,     /* Current size of the allocation, in elements */
-  int *pIdx         /* Write the index of a new slot here */
-){
-  char *z;
-  if( *pnEntry >= *pnAlloc ){
-    void *pNew;
-    int newSize;
-    newSize = (*pnAlloc)*2 + initSize;
-    pNew = sqlite3DbRealloc(db, pArray, newSize*szEntry);
-    if( pNew==0 ){
-      *pIdx = -1;
-      return pArray;
+SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse *pParse, int iReg){
+  int i;
+  struct yColCache *p;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg==iReg ){
+      cacheEntryClear(pParse, p);
+      p->iReg = 0;
     }
-    *pnAlloc = newSize;
-    pArray = pNew;
   }
-  z = (char*)pArray;
-  memset(&z[*pnEntry * szEntry], 0, szEntry);
-  *pIdx = *pnEntry;
-  ++*pnEntry;
-  return pArray;
 }
 
 /*
-** Append a new element to the given IdList.  Create a new IdList if
-** need be.
-**
-** A new IdList is returned, or NULL if malloc() fails.
+** Remember the current column cache context.  Any new entries added
+** added to the column cache after this call are removed when the
+** corresponding pop occurs.
 */
-SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3 *db, IdList *pList, Token *pToken){
-  int i;
-  if( pList==0 ){
-    pList = sqlite3DbMallocZero(db, sizeof(IdList) );
-    if( pList==0 ) return 0;
-    pList->nAlloc = 0;
-  }
-  pList->a = sqlite3ArrayAllocate(
-      db,
-      pList->a,
-      sizeof(pList->a[0]),
-      5,
-      &pList->nId,
-      &pList->nAlloc,
-      &i
-  );
-  if( i<0 ){
-    sqlite3IdListDelete(pList);
-    return 0;
-  }
-  pList->a[i].zName = sqlite3NameFromToken(db, pToken);
-  return pList;
+SQLITE_PRIVATE void sqlite3ExprCachePush(Parse *pParse){
+  pParse->iCacheLevel++;
 }
 
 /*
-** Delete an IdList.
+** Remove from the column cache any entries that were added since the
+** the previous N Push operations.  In other words, restore the cache
+** to the state it was in N Pushes ago.
 */
-SQLITE_PRIVATE void sqlite3IdListDelete(IdList *pList){
+SQLITE_PRIVATE void sqlite3ExprCachePop(Parse *pParse, int N){
   int i;
-  if( pList==0 ) return;
-  for(i=0; i<pList->nId; i++){
-    sqlite3_free(pList->a[i].zName);
+  struct yColCache *p;
+  assert( N>0 );
+  assert( pParse->iCacheLevel>=N );
+  pParse->iCacheLevel -= N;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg && p->iLevel>pParse->iCacheLevel ){
+      cacheEntryClear(pParse, p);
+      p->iReg = 0;
+    }
   }
-  sqlite3_free(pList->a);
-  sqlite3_free(pList);
 }
 
 /*
-** Return the index in pList of the identifier named zId.  Return -1
-** if not found.
+** When a cached column is reused, make sure that its register is
+** no longer available as a temp register.  ticket #3879:  that same
+** register might be in the cache in multiple places, so be sure to
+** get them all.
 */
-SQLITE_PRIVATE int sqlite3IdListIndex(IdList *pList, const char *zName){
+static void sqlite3ExprCachePinRegister(Parse *pParse, int iReg){
   int i;
-  if( pList==0 ) return -1;
-  for(i=0; i<pList->nId; i++){
-    if( sqlite3StrICmp(pList->a[i].zName, zName)==0 ) return i;
+  struct yColCache *p;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg==iReg ){
+      p->tempReg = 0;
+    }
   }
-  return -1;
 }
 
 /*
-** Append a new table name to the given SrcList.  Create a new SrcList if
-** need be.  A new entry is created in the SrcList even if pToken is NULL.
-**
-** A new SrcList is returned, or NULL if malloc() fails.
-**
-** If pDatabase is not null, it means that the table has an optional
-** database name prefix.  Like this:  "database.table".  The pDatabase
-** points to the table name and the pTable points to the database name.
-** The SrcList.a[].zName field is filled with the table name which might
-** come from pTable (if pDatabase is NULL) or from pDatabase.  
-** SrcList.a[].zDatabase is filled with the database name from pTable,
-** or with NULL if no database is specified.
-**
-** In other words, if call like this:
-**
-**         sqlite3SrcListAppend(D,A,B,0);
-**
-** Then B is a table name and the database name is unspecified.  If called
-** like this:
+** Generate code that will extract the iColumn-th column from
+** table pTab and store the column value in a register.  An effort
+** is made to store the column value in register iReg, but this is
+** not guaranteed.  The location of the column value is returned.
 **
-**         sqlite3SrcListAppend(D,A,B,C);
+** There must be an open cursor to pTab in iTable when this routine
+** is called.  If iColumn<0 then code is generated that extracts the rowid.
 **
-** Then C is the table name and B is the database name.
+** This routine might attempt to reuse the value of the column that
+** has already been loaded into a register.  The value will always
+** be used if it has not undergone any affinity changes.  But if
+** an affinity change has occurred, then the cached value will only be
+** used if allowAffChng is true.
 */
-SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(
-  sqlite3 *db,        /* Connection to notify of malloc failures */
-  SrcList *pList,     /* Append to this SrcList. NULL creates a new SrcList */
-  Token *pTable,      /* Table to append */
-  Token *pDatabase    /* Database of the table */
+SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(
+  Parse *pParse,   /* Parsing and code generating context */
+  Table *pTab,     /* Description of the table we are reading from */
+  int iColumn,     /* Index of the table column */
+  int iTable,      /* The cursor pointing to the table */
+  int iReg,        /* Store results here */
+  int allowAffChng /* True if prior affinity changes are OK */
 ){
-  struct SrcList_item *pItem;
-  if( pList==0 ){
-    pList = sqlite3DbMallocZero(db, sizeof(SrcList) );
-    if( pList==0 ) return 0;
-    pList->nAlloc = 1;
-  }
-  if( pList->nSrc>=pList->nAlloc ){
-    SrcList *pNew;
-    pList->nAlloc *= 2;
-    pNew = sqlite3DbRealloc(db, pList,
-               sizeof(*pList) + (pList->nAlloc-1)*sizeof(pList->a[0]) );
-    if( pNew==0 ){
-      sqlite3SrcListDelete(pList);
-      return 0;
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct yColCache *p;
+
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg>0 && p->iTable==iTable && p->iColumn==iColumn
+           && (!p->affChange || allowAffChng) ){
+      p->lru = pParse->iCacheCnt++;
+      sqlite3ExprCachePinRegister(pParse, p->iReg);
+      return p->iReg;
     }
-    pList = pNew;
-  }
-  pItem = &pList->a[pList->nSrc];
-  memset(pItem, 0, sizeof(pList->a[0]));
-  if( pDatabase && pDatabase->z==0 ){
-    pDatabase = 0;
-  }
-  if( pDatabase && pTable ){
-    Token *pTemp = pDatabase;
-    pDatabase = pTable;
-    pTable = pTemp;
+  }  
+  assert( v!=0 );
+  if( iColumn<0 ){
+    sqlite3VdbeAddOp2(v, OP_Rowid, iTable, iReg);
+  }else if( ALWAYS(pTab!=0) ){
+    int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
+    sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
+    sqlite3ColumnDefault(v, pTab, iColumn, iReg);
   }
-  pItem->zName = sqlite3NameFromToken(db, pTable);
-  pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
-  pItem->iCursor = -1;
-  pItem->isPopulated = 0;
-  pList->nSrc++;
-  return pList;
+  sqlite3ExprCacheStore(pParse, iTable, iColumn, iReg);
+  return iReg;
 }
 
 /*
-** Assign cursors to all tables in a SrcList
+** Clear all column cache entries.
 */
-SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
+SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse *pParse){
   int i;
-  struct SrcList_item *pItem;
-  assert(pList || pParse->db->mallocFailed );
-  if( pList ){
-    for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
-      if( pItem->iCursor>=0 ) break;
-      pItem->iCursor = pParse->nTab++;
-      if( pItem->pSelect ){
-        sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
-      }
+  struct yColCache *p;
+
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    if( p->iReg ){
+      cacheEntryClear(pParse, p);
+      p->iReg = 0;
     }
   }
 }
 
 /*
-** Delete an entire SrcList including all its substructure.
+** Record the fact that an affinity change has occurred on iCount
+** registers starting with iStart.
 */
-SQLITE_PRIVATE void sqlite3SrcListDelete(SrcList *pList){
+SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
+  int iEnd = iStart + iCount - 1;
   int i;
-  struct SrcList_item *pItem;
-  if( pList==0 ) return;
-  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
-    sqlite3_free(pItem->zDatabase);
-    sqlite3_free(pItem->zName);
-    sqlite3_free(pItem->zAlias);
-    sqlite3DeleteTable(pItem->pTab);
-    sqlite3SelectDelete(pItem->pSelect);
-    sqlite3ExprDelete(pItem->pOn);
-    sqlite3IdListDelete(pItem->pUsing);
-  }
-  sqlite3_free(pList);
-}
-
-/*
-** This routine is called by the parser to add a new term to the
-** end of a growing FROM clause.  The "p" parameter is the part of
-** the FROM clause that has already been constructed.  "p" is NULL
-** if this is the first term of the FROM clause.  pTable and pDatabase
-** are the name of the table and database named in the FROM clause term.
-** pDatabase is NULL if the database name qualifier is missing - the
-** usual case.  If the term has a alias, then pAlias points to the
-** alias token.  If the term is a subquery, then pSubquery is the
-** SELECT statement that the subquery encodes.  The pTable and
-** pDatabase parameters are NULL for subqueries.  The pOn and pUsing
-** parameters are the content of the ON and USING clauses.
-**
-** Return a new SrcList which encodes is the FROM with the new
-** term added.
-*/
-SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(
-  Parse *pParse,          /* Parsing context */
-  SrcList *p,             /* The left part of the FROM clause already seen */
-  Token *pTable,          /* Name of the table to add to the FROM clause */
-  Token *pDatabase,       /* Name of the database containing pTable */
-  Token *pAlias,          /* The right-hand side of the AS subexpression */
-  Select *pSubquery,      /* A subquery used in place of a table name */
-  Expr *pOn,              /* The ON clause of a join */
-  IdList *pUsing          /* The USING clause of a join */
-){
-  struct SrcList_item *pItem;
-  sqlite3 *db = pParse->db;
-  p = sqlite3SrcListAppend(db, p, pTable, pDatabase);
-  if( p==0 || p->nSrc==0 ){
-    sqlite3ExprDelete(pOn);
-    sqlite3IdListDelete(pUsing);
-    sqlite3SelectDelete(pSubquery);
-    return p;
-  }
-  pItem = &p->a[p->nSrc-1];
-  if( pAlias && pAlias->n ){
-    pItem->zAlias = sqlite3NameFromToken(db, pAlias);
-  }
-  pItem->pSelect = pSubquery;
-  pItem->pOn = pOn;
-  pItem->pUsing = pUsing;
-  return p;
-}
-
-/*
-** When building up a FROM clause in the parser, the join operator
-** is initially attached to the left operand.  But the code generator
-** expects the join operator to be on the right operand.  This routine
-** Shifts all join operators from left to right for an entire FROM
-** clause.
-**
-** Example: Suppose the join is like this:
-**
-**           A natural cross join B
-**
-** The operator is "natural cross join".  The A and B operands are stored
-** in p->a[0] and p->a[1], respectively.  The parser initially stores the
-** operator with A.  This routine shifts that operator over to B.
-*/
-SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList *p){
-  if( p && p->a ){
-    int i;
-    for(i=p->nSrc-1; i>0; i--){
-      p->a[i].jointype = p->a[i-1].jointype;
+  struct yColCache *p;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    int r = p->iReg;
+    if( r>=iStart && r<=iEnd ){
+      p->affChange = 1;
     }
-    p->a[0].jointype = 0;
   }
 }
 
 /*
-** Begin a transaction
+** Generate code to move content from registers iFrom...iFrom+nReg-1
+** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
 */
-SQLITE_PRIVATE void sqlite3BeginTransaction(Parse *pParse, int type){
-  sqlite3 *db;
-  Vdbe *v;
+SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
   int i;
-
-  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
-  if( pParse->nErr || db->mallocFailed ) return;
-  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "BEGIN", 0, 0) ) return;
-
-  v = sqlite3GetVdbe(pParse);
-  if( !v ) return;
-  if( type!=TK_DEFERRED ){
-    for(i=0; i<db->nDb; i++){
-      sqlite3VdbeAddOp2(v, OP_Transaction, i, (type==TK_EXCLUSIVE)+1);
-      sqlite3VdbeUsesBtree(v, i);
+  struct yColCache *p;
+  if( NEVER(iFrom==iTo) ) return;
+  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    int x = p->iReg;
+    if( x>=iFrom && x<iFrom+nReg ){
+      p->iReg += iTo-iFrom;
     }
   }
-  sqlite3VdbeAddOp2(v, OP_AutoCommit, 0, 0);
-}
-
-/*
-** Commit a transaction
-*/
-SQLITE_PRIVATE void sqlite3CommitTransaction(Parse *pParse){
-  sqlite3 *db;
-  Vdbe *v;
-
-  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
-  if( pParse->nErr || db->mallocFailed ) return;
-  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "COMMIT", 0, 0) ) return;
-
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3VdbeAddOp2(v, OP_AutoCommit, 1, 0);
-  }
 }
 
 /*
-** Rollback a transaction
+** Generate code to copy content from registers iFrom...iFrom+nReg-1
+** over to iTo..iTo+nReg-1.
 */
-SQLITE_PRIVATE void sqlite3RollbackTransaction(Parse *pParse){
-  sqlite3 *db;
-  Vdbe *v;
-
-  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
-  if( pParse->nErr || db->mallocFailed ) return;
-  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "ROLLBACK", 0, 0) ) return;
-
-  v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3VdbeAddOp2(v, OP_AutoCommit, 1, 1);
+SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
+  int i;
+  if( NEVER(iFrom==iTo) ) return;
+  for(i=0; i<nReg; i++){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, iFrom+i, iTo+i);
   }
 }
 
 /*
-** Make sure the TEMP database is open and available for use.  Return
-** the number of errors.  Leave any error messages in the pParse structure.
+** Return true if any register in the range iFrom..iTo (inclusive)
+** is used as part of the column cache.
 */
-SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *pParse){
-  sqlite3 *db = pParse->db;
-  if( db->aDb[1].pBt==0 && !pParse->explain ){
-    int rc;
-    static const int flags = 
-          SQLITE_OPEN_READWRITE |
-          SQLITE_OPEN_CREATE |
-          SQLITE_OPEN_EXCLUSIVE |
-          SQLITE_OPEN_DELETEONCLOSE |
-          SQLITE_OPEN_TEMP_DB;
-
-    rc = sqlite3BtreeFactory(db, 0, 0, SQLITE_DEFAULT_CACHE_SIZE, flags,
-                                 &db->aDb[1].pBt);
-    if( rc!=SQLITE_OK ){
-      sqlite3ErrorMsg(pParse, "unable to open a temporary database "
-        "file for storing temporary tables");
-      pParse->rc = rc;
-      return 1;
-    }
-    assert( (db->flags & SQLITE_InTrans)==0 || db->autoCommit );
-    assert( db->aDb[1].pSchema );
-    sqlite3PagerJournalMode(sqlite3BtreePager(db->aDb[1].pBt),
-                            db->dfltJournalMode);
+static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
+  int i;
+  struct yColCache *p;
+  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+    int r = p->iReg;
+    if( r>=iFrom && r<=iTo ) return 1;
   }
   return 0;
 }
 
 /*
-** Generate VDBE code that will verify the schema cookie and start
-** a read-transaction for all named database files.
-**
-** It is important that all schema cookies be verified and all
-** read transactions be started before anything else happens in
-** the VDBE program.  But this routine can be called after much other
-** code has been generated.  So here is what we do:
-**
-** The first time this routine is called, we code an OP_Goto that
-** will jump to a subroutine at the end of the program.  Then we
-** record every database that needs its schema verified in the
-** pParse->cookieMask field.  Later, after all other code has been
-** generated, the subroutine that does the cookie verifications and
-** starts the transactions will be coded and the OP_Goto P2 value
-** will be made to point to that subroutine.  The generation of the
-** cookie verification subroutine code happens in sqlite3FinishCoding().
-**
-** If iDb<0 then code the OP_Goto only - don't set flag to verify the
-** schema on any databases.  This can be used to position the OP_Goto
-** early in the code, before we know if any database tables will be used.
+** If the last instruction coded is an ephemeral copy of any of
+** the registers in the nReg registers beginning with iReg, then
+** convert the last instruction from OP_SCopy to OP_Copy.
 */
-SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse *pParse, int iDb){
-  sqlite3 *db;
+SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
+  VdbeOp *pOp;
   Vdbe *v;
-  int mask;
 
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;  /* This only happens if there was a prior error */
-  db = pParse->db;
-  if( pParse->cookieGoto==0 ){
-    pParse->cookieGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0)+1;
-  }
-  if( iDb>=0 ){
-    assert( iDb<db->nDb );
-    assert( db->aDb[iDb].pBt!=0 || iDb==1 );
-    assert( iDb<SQLITE_MAX_ATTACHED+2 );
-    mask = 1<<iDb;
-    if( (pParse->cookieMask & mask)==0 ){
-      pParse->cookieMask |= mask;
-      pParse->cookieValue[iDb] = db->aDb[iDb].pSchema->schema_cookie;
-      if( !OMIT_TEMPDB && iDb==1 ){
-        sqlite3OpenTempDatabase(pParse);
-      }
-    }
+  assert( pParse->db->mallocFailed==0 );
+  v = pParse->pVdbe;
+  assert( v!=0 );
+  pOp = sqlite3VdbeGetOp(v, -1);
+  assert( pOp!=0 );
+  if( pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
+    pOp->opcode = OP_Copy;
   }
 }
 
 /*
-** Generate VDBE code that prepares for doing an operation that
-** might change the database.
+** Generate code to store the value of the iAlias-th alias in register
+** target.  The first time this is called, pExpr is evaluated to compute
+** the value of the alias.  The value is stored in an auxiliary register
+** and the number of that register is returned.  On subsequent calls,
+** the register number is returned without generating any code.
 **
-** This routine starts a new transaction if we are not already within
-** a transaction.  If we are already within a transaction, then a checkpoint
-** is set if the setStatement parameter is true.  A checkpoint should
-** be set for operations that might fail (due to a constraint) part of
-** the way through and which will need to undo some writes without having to
-** rollback the whole transaction.  For operations where all constraints
-** can be checked before any changes are made to the database, it is never
-** necessary to undo a write and the checkpoint should not be set.
+** Note that in order for this to work, code must be generated in the
+** same order that it is executed.
 **
-** Only database iDb and the temp database are made writable by this call.
-** If iDb==0, then the main and temp databases are made writable.   If
-** iDb==1 then only the temp database is made writable.  If iDb>1 then the
-** specified auxiliary database and the temp database are made writable.
-*/
-SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse *pParse, int setStatement, int iDb){
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;
-  sqlite3CodeVerifySchema(pParse, iDb);
-  pParse->writeMask |= 1<<iDb;
-  if( setStatement && pParse->nested==0 ){
-    sqlite3VdbeAddOp1(v, OP_Statement, iDb);
-  }
-  if( (OMIT_TEMPDB || iDb!=1) && pParse->db->aDb[1].pBt!=0 ){
-    sqlite3BeginWriteOperation(pParse, setStatement, 1);
-  }
-}
-
-/*
-** Check to see if pIndex uses the collating sequence pColl.  Return
-** true if it does and false if it does not.
-*/
-#ifndef SQLITE_OMIT_REINDEX
-static int collationMatch(const char *zColl, Index *pIndex){
-  int i;
-  for(i=0; i<pIndex->nColumn; i++){
-    const char *z = pIndex->azColl[i];
-    if( z==zColl || (z && zColl && 0==sqlite3StrICmp(z, zColl)) ){
-      return 1;
-    }
-  }
-  return 0;
-}
-#endif
-
-/*
-** Recompute all indices of pTab that use the collating sequence pColl.
-** If pColl==0 then recompute all indices of pTab.
+** Aliases are numbered starting with 1.  So iAlias is in the range
+** of 1 to pParse->nAlias inclusive.  
+**
+** pParse->aAlias[iAlias-1] records the register number where the value
+** of the iAlias-th alias is stored.  If zero, that means that the
+** alias has not yet been computed.
 */
-#ifndef SQLITE_OMIT_REINDEX
-static void reindexTable(Parse *pParse, Table *pTab, char const *zColl){
-  Index *pIndex;              /* An index associated with pTab */
-
-  for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
-    if( zColl==0 || collationMatch(zColl, pIndex) ){
-      int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-      sqlite3BeginWriteOperation(pParse, 0, iDb);
-      sqlite3RefillIndex(pParse, pIndex, -1);
+static int codeAlias(Parse *pParse, int iAlias, Expr *pExpr, int target){
+#if 0
+  sqlite3 *db = pParse->db;
+  int iReg;
+  if( pParse->nAliasAlloc<pParse->nAlias ){
+    pParse->aAlias = sqlite3DbReallocOrFree(db, pParse->aAlias,
+                                 sizeof(pParse->aAlias[0])*pParse->nAlias );
+    testcase( db->mallocFailed && pParse->nAliasAlloc>0 );
+    if( db->mallocFailed ) return 0;
+    memset(&pParse->aAlias[pParse->nAliasAlloc], 0,
+           (pParse->nAlias-pParse->nAliasAlloc)*sizeof(pParse->aAlias[0]));
+    pParse->nAliasAlloc = pParse->nAlias;
+  }
+  assert( iAlias>0 && iAlias<=pParse->nAlias );
+  iReg = pParse->aAlias[iAlias-1];
+  if( iReg==0 ){
+    if( pParse->iCacheLevel>0 ){
+      iReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+    }else{
+      iReg = ++pParse->nMem;
+      sqlite3ExprCode(pParse, pExpr, iReg);
+      pParse->aAlias[iAlias-1] = iReg;
     }
   }
-}
+  return iReg;
+#else
+  UNUSED_PARAMETER(iAlias);
+  return sqlite3ExprCodeTarget(pParse, pExpr, target);
 #endif
-
-/*
-** Recompute all indices of all tables in all databases where the
-** indices use the collating sequence pColl.  If pColl==0 then recompute
-** all indices everywhere.
-*/
-#ifndef SQLITE_OMIT_REINDEX
-static void reindexDatabases(Parse *pParse, char const *zColl){
-  Db *pDb;                    /* A single database */
-  int iDb;                    /* The database index number */
-  sqlite3 *db = pParse->db;   /* The database connection */
-  HashElem *k;                /* For looping over tables in pDb */
-  Table *pTab;                /* A table in the database */
-
-  for(iDb=0, pDb=db->aDb; iDb<db->nDb; iDb++, pDb++){
-    assert( pDb!=0 );
-    for(k=sqliteHashFirst(&pDb->pSchema->tblHash);  k; k=sqliteHashNext(k)){
-      pTab = (Table*)sqliteHashData(k);
-      reindexTable(pParse, pTab, zColl);
-    }
-  }
 }
-#endif
 
 /*
-** Generate code for the REINDEX command.
-**
-**        REINDEX                            -- 1
-**        REINDEX  <collation>               -- 2
-**        REINDEX  ?<database>.?<tablename>  -- 3
-**        REINDEX  ?<database>.?<indexname>  -- 4
+** Generate code into the current Vdbe to evaluate the given
+** expression.  Attempt to store the results in register "target".
+** Return the register where results are stored.
 **
-** Form 1 causes all indices in all attached databases to be rebuilt.
-** Form 2 rebuilds all indices in all databases that use the named
-** collating function.  Forms 3 and 4 rebuild the named index or all
-** indices associated with the named table.
+** With this routine, there is no guarantee that results will
+** be stored in target.  The result might be stored in some other
+** register if it is convenient to do so.  The calling function
+** must check the return code and move the results to the desired
+** register.
 */
-#ifndef SQLITE_OMIT_REINDEX
-SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
-  CollSeq *pColl;             /* Collating sequence to be reindexed, or NULL */
-  char *z;                    /* Name of a table or index */
-  const char *zDb;            /* Name of the database */
-  Table *pTab;                /* A table in the database */
-  Index *pIndex;              /* An index associated with pTab */
-  int iDb;                    /* The database index number */
-  sqlite3 *db = pParse->db;   /* The database connection */
-  Token *pObjName;            /* Name of the table or index to be reindexed */
+SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
+  Vdbe *v = pParse->pVdbe;  /* The VM under construction */
+  int op;                   /* The opcode being coded */
+  int inReg = target;       /* Results stored in register inReg */
+  int regFree1 = 0;         /* If non-zero free this temporary register */
+  int regFree2 = 0;         /* If non-zero free this temporary register */
+  int r1, r2, r3, r4;       /* Various register numbers */
+  sqlite3 *db = pParse->db; /* The database connection */
 
-  /* Read the database schema. If an error occurs, leave an error message
-  ** and code in pParse and return NULL. */
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-    return;
+  assert( target>0 && target<=pParse->nMem );
+  if( v==0 ){
+    assert( pParse->db->mallocFailed );
+    return 0;
   }
 
-  if( pName1==0 || pName1->z==0 ){
-    reindexDatabases(pParse, 0);
-    return;
-  }else if( pName2==0 || pName2->z==0 ){
-    char *zColl;
-    assert( pName1->z );
-    zColl = sqlite3NameFromToken(pParse->db, pName1);
-    if( !zColl ) return;
-    pColl = sqlite3FindCollSeq(db, ENC(db), zColl, -1, 0);
-    if( pColl ){
-      if( zColl ){
-        reindexDatabases(pParse, zColl);
-        sqlite3_free(zColl);
+  if( pExpr==0 ){
+    op = TK_NULL;
+  }else{
+    op = pExpr->op;
+  }
+  switch( op ){
+    case TK_AGG_COLUMN: {
+      AggInfo *pAggInfo = pExpr->pAggInfo;
+      struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
+      if( !pAggInfo->directMode ){
+        assert( pCol->iMem>0 );
+        inReg = pCol->iMem;
+        break;
+      }else if( pAggInfo->useSortingIdx ){
+        sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
+                              pCol->iSorterColumn, target);
+        break;
       }
-      return;
+      /* Otherwise, fall thru into the TK_COLUMN case */
     }
-    sqlite3_free(zColl);
-  }
-  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
-  if( iDb<0 ) return;
-  z = sqlite3NameFromToken(db, pObjName);
-  if( z==0 ) return;
-  zDb = db->aDb[iDb].zName;
-  pTab = sqlite3FindTable(db, z, zDb);
-  if( pTab ){
-    reindexTable(pParse, pTab, 0);
-    sqlite3_free(z);
-    return;
-  }
-  pIndex = sqlite3FindIndex(db, z, zDb);
-  sqlite3_free(z);
-  if( pIndex ){
-    sqlite3BeginWriteOperation(pParse, 0, iDb);
-    sqlite3RefillIndex(pParse, pIndex, -1);
-    return;
-  }
-  sqlite3ErrorMsg(pParse, "unable to identify the object to be reindexed");
-}
-#endif
-
-/*
-** Return a dynamicly allocated KeyInfo structure that can be used
-** with OP_OpenRead or OP_OpenWrite to access database index pIdx.
-**
-** If successful, a pointer to the new structure is returned. In this case
-** the caller is responsible for calling sqlite3_free() on the returned 
-** pointer. If an error occurs (out of memory or missing collation 
-** sequence), NULL is returned and the state of pParse updated to reflect
-** the error.
-*/
-SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
-  int i;
-  int nCol = pIdx->nColumn;
-  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
-  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZero(pParse->db, nBytes);
-
-  if( pKey ){
-    pKey->db = pParse->db;
-    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
-    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );
-    for(i=0; i<nCol; i++){
-      char *zColl = pIdx->azColl[i];
-      assert( zColl );
-      pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl, -1);
-      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
+    case TK_COLUMN: {
+      if( pExpr->iTable<0 ){
+        /* This only happens when coding check constraints */
+        assert( pParse->ckBase>0 );
+        inReg = pExpr->iColumn + pParse->ckBase;
+      }else{
+        testcase( (pExpr->flags & EP_AnyAff)!=0 );
+        inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
+                                 pExpr->iColumn, pExpr->iTable, target,
+                                 pExpr->flags & EP_AnyAff);
+      }
+      break;
     }
-    pKey->nField = nCol;
-  }
-
-  if( pParse->nErr ){
-    sqlite3_free(pKey);
-    pKey = 0;
-  }
-  return pKey;
-}
-
-/************** End of build.c ***********************************************/
-/************** Begin file callback.c ****************************************/
-/*
-** 2005 May 23 
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-**
-** This file contains functions used to access the internal hash tables
-** of user defined functions and collation sequences.
-**
-** $Id: callback.c,v 1.23 2007/08/29 12:31:26 danielk1977 Exp $
-*/
-
-
-/*
-** Invoke the 'collation needed' callback to request a collation sequence
-** in the database text encoding of name zName, length nName.
-** If the collation sequence
-*/
-static void callCollNeeded(sqlite3 *db, const char *zName, int nName){
-  assert( !db->xCollNeeded || !db->xCollNeeded16 );
-  if( nName<0 ) nName = strlen(zName);
-  if( db->xCollNeeded ){
-    char *zExternal = sqlite3DbStrNDup(db, zName, nName);
-    if( !zExternal ) return;
-    db->xCollNeeded(db->pCollNeededArg, db, (int)ENC(db), zExternal);
-    sqlite3_free(zExternal);
-  }
-#ifndef SQLITE_OMIT_UTF16
-  if( db->xCollNeeded16 ){
-    char const *zExternal;
-    sqlite3_value *pTmp = sqlite3ValueNew(db);
-    sqlite3ValueSetStr(pTmp, nName, zName, SQLITE_UTF8, SQLITE_STATIC);
-    zExternal = sqlite3ValueText(pTmp, SQLITE_UTF16NATIVE);
-    if( zExternal ){
-      db->xCollNeeded16(db->pCollNeededArg, db, (int)ENC(db), zExternal);
+    case TK_INTEGER: {
+      codeInteger(v, pExpr, 0, target);
+      break;
     }
-    sqlite3ValueFree(pTmp);
-  }
-#endif
-}
-
-/*
-** This routine is called if the collation factory fails to deliver a
-** collation function in the best encoding but there may be other versions
-** of this collation function (for other text encodings) available. Use one
-** of these instead if they exist. Avoid a UTF-8 <-> UTF-16 conversion if
-** possible.
-*/
-static int synthCollSeq(sqlite3 *db, CollSeq *pColl){
-  CollSeq *pColl2;
-  char *z = pColl->zName;
-  int n = strlen(z);
-  int i;
-  static const u8 aEnc[] = { SQLITE_UTF16BE, SQLITE_UTF16LE, SQLITE_UTF8 };
-  for(i=0; i<3; i++){
-    pColl2 = sqlite3FindCollSeq(db, aEnc[i], z, n, 0);
-    if( pColl2->xCmp!=0 ){
-      memcpy(pColl, pColl2, sizeof(CollSeq));
-      pColl->xDel = 0;         /* Do not copy the destructor */
-      return SQLITE_OK;
+    case TK_FLOAT: {
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      codeReal(v, pExpr->u.zToken, 0, target);
+      break;
     }
-  }
-  return SQLITE_ERROR;
-}
-
-/*
-** This function is responsible for invoking the collation factory callback
-** or substituting a collation sequence of a different encoding when the
-** requested collation sequence is not available in the database native
-** encoding.
-** 
-** If it is not NULL, then pColl must point to the database native encoding 
-** collation sequence with name zName, length nName.
-**
-** The return value is either the collation sequence to be used in database
-** db for collation type name zName, length nName, or NULL, if no collation
-** sequence can be found.
-*/
-SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(
-  sqlite3* db, 
-  CollSeq *pColl, 
-  const char *zName, 
-  int nName
-){
-  CollSeq *p;
-
-  p = pColl;
-  if( !p ){
-    p = sqlite3FindCollSeq(db, ENC(db), zName, nName, 0);
-  }
-  if( !p || !p->xCmp ){
-    /* No collation sequence of this type for this encoding is registered.
-    ** Call the collation factory to see if it can supply us with one.
-    */
-    callCollNeeded(db, zName, nName);
-    p = sqlite3FindCollSeq(db, ENC(db), zName, nName, 0);
-  }
-  if( p && !p->xCmp && synthCollSeq(db, p) ){
-    p = 0;
-  }
-  assert( !p || p->xCmp );
-  return p;
-}
-
-/*
-** This routine is called on a collation sequence before it is used to
-** check that it is defined. An undefined collation sequence exists when
-** a database is loaded that contains references to collation sequences
-** that have not been defined by sqlite3_create_collation() etc.
-**
-** If required, this routine calls the 'collation needed' callback to
-** request a definition of the collating sequence. If this doesn't work, 
-** an equivalent collating sequence that uses a text encoding different
-** from the main database is substituted, if one is available.
-*/
-SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *pParse, CollSeq *pColl){
-  if( pColl ){
-    const char *zName = pColl->zName;
-    CollSeq *p = sqlite3GetCollSeq(pParse->db, pColl, zName, -1);
-    if( !p ){
-      if( pParse->nErr==0 ){
-        sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
-      }
-      pParse->nErr++;
-      return SQLITE_ERROR;
+    case TK_STRING: {
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      sqlite3VdbeAddOp4(v, OP_String8, 0, target, 0, pExpr->u.zToken, 0);
+      break;
     }
-    assert( p==pColl );
-  }
-  return SQLITE_OK;
-}
-
+    case TK_NULL: {
+      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+      break;
+    }
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+    case TK_BLOB: {
+      int n;
+      const char *z;
+      char *zBlob;
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
+      assert( pExpr->u.zToken[1]=='\'' );
+      z = &pExpr->u.zToken[2];
+      n = sqlite3Strlen30(z) - 1;
+      assert( z[n]=='\'' );
+      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
+      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
+      break;
+    }
+#endif
+    case TK_VARIABLE: {
+      VdbeOp *pOp;
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      assert( pExpr->u.zToken!=0 );
+      assert( pExpr->u.zToken[0]!=0 );
+      if( pExpr->u.zToken[1]==0
+         && (pOp = sqlite3VdbeGetOp(v, -1))->opcode==OP_Variable
+         && pOp->p1+pOp->p3==pExpr->iTable
+         && pOp->p2+pOp->p3==target
+         && pOp->p4.z==0
+      ){
+        /* If the previous instruction was a copy of the previous unnamed
+        ** parameter into the previous register, then simply increment the
+        ** repeat count on the prior instruction rather than making a new
+        ** instruction.
+        */
+        pOp->p3++;
+      }else{
+        sqlite3VdbeAddOp3(v, OP_Variable, pExpr->iTable, target, 1);
+        if( pExpr->u.zToken[1]!=0 ){
+          sqlite3VdbeChangeP4(v, -1, pExpr->u.zToken, 0);
+        }
+      }
+      break;
+    }
+    case TK_REGISTER: {
+      inReg = pExpr->iTable;
+      break;
+    }
+    case TK_AS: {
+      inReg = codeAlias(pParse, pExpr->iTable, pExpr->pLeft, target);
+      break;
+    }
+#ifndef SQLITE_OMIT_CAST
+    case TK_CAST: {
+      /* Expressions of the form:   CAST(pLeft AS token) */
+      int aff, to_op;
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      aff = sqlite3AffinityType(pExpr->u.zToken);
+      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
+      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
+      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
+      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
+      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
+      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
+      testcase( to_op==OP_ToText );
+      testcase( to_op==OP_ToBlob );
+      testcase( to_op==OP_ToNumeric );
+      testcase( to_op==OP_ToInt );
+      testcase( to_op==OP_ToReal );
+      if( inReg!=target ){
+        sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
+        inReg = target;
+      }
+      sqlite3VdbeAddOp1(v, to_op, inReg);
+      testcase( usedAsColumnCache(pParse, inReg, inReg) );
+      sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
+      break;
+    }
+#endif /* SQLITE_OMIT_CAST */
+    case TK_LT:
+    case TK_LE:
+    case TK_GT:
+    case TK_GE:
+    case TK_NE:
+    case TK_EQ: {
+      assert( TK_LT==OP_Lt );
+      assert( TK_LE==OP_Le );
+      assert( TK_GT==OP_Gt );
+      assert( TK_GE==OP_Ge );
+      assert( TK_EQ==OP_Eq );
+      assert( TK_NE==OP_Ne );
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, inReg, SQLITE_STOREP2);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_IS:
+    case TK_ISNOT: {
+      testcase( op==TK_IS );
+      testcase( op==TK_ISNOT );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      op = (op==TK_IS) ? TK_EQ : TK_NE;
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, inReg, SQLITE_STOREP2 | SQLITE_NULLEQ);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_AND:
+    case TK_OR:
+    case TK_PLUS:
+    case TK_STAR:
+    case TK_MINUS:
+    case TK_REM:
+    case TK_BITAND:
+    case TK_BITOR:
+    case TK_SLASH:
+    case TK_LSHIFT:
+    case TK_RSHIFT: 
+    case TK_CONCAT: {
+      assert( TK_AND==OP_And );
+      assert( TK_OR==OP_Or );
+      assert( TK_PLUS==OP_Add );
+      assert( TK_MINUS==OP_Subtract );
+      assert( TK_REM==OP_Remainder );
+      assert( TK_BITAND==OP_BitAnd );
+      assert( TK_BITOR==OP_BitOr );
+      assert( TK_SLASH==OP_Divide );
+      assert( TK_LSHIFT==OP_ShiftLeft );
+      assert( TK_RSHIFT==OP_ShiftRight );
+      assert( TK_CONCAT==OP_Concat );
+      testcase( op==TK_AND );
+      testcase( op==TK_OR );
+      testcase( op==TK_PLUS );
+      testcase( op==TK_MINUS );
+      testcase( op==TK_REM );
+      testcase( op==TK_BITAND );
+      testcase( op==TK_BITOR );
+      testcase( op==TK_SLASH );
+      testcase( op==TK_LSHIFT );
+      testcase( op==TK_RSHIFT );
+      testcase( op==TK_CONCAT );
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+      sqlite3VdbeAddOp3(v, op, r2, r1, target);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_UMINUS: {
+      Expr *pLeft = pExpr->pLeft;
+      assert( pLeft );
+      if( pLeft->op==TK_FLOAT ){
+        assert( !ExprHasProperty(pExpr, EP_IntValue) );
+        codeReal(v, pLeft->u.zToken, 1, target);
+      }else if( pLeft->op==TK_INTEGER ){
+        codeInteger(v, pLeft, 1, target);
+      }else{
+        regFree1 = r1 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
+        r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree2);
+        sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
+        testcase( regFree2==0 );
+      }
+      inReg = target;
+      break;
+    }
+    case TK_BITNOT:
+    case TK_NOT: {
+      assert( TK_BITNOT==OP_BitNot );
+      assert( TK_NOT==OP_Not );
+      testcase( op==TK_BITNOT );
+      testcase( op==TK_NOT );
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+      testcase( regFree1==0 );
+      inReg = target;
+      sqlite3VdbeAddOp2(v, op, r1, inReg);
+      break;
+    }
+    case TK_ISNULL:
+    case TK_NOTNULL: {
+      int addr;
+      assert( TK_ISNULL==OP_IsNull );
+      assert( TK_NOTNULL==OP_NotNull );
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+      testcase( regFree1==0 );
+      addr = sqlite3VdbeAddOp1(v, op, r1);
+      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
+      sqlite3VdbeJumpHere(v, addr);
+      break;
+    }
+    case TK_AGG_FUNCTION: {
+      AggInfo *pInfo = pExpr->pAggInfo;
+      if( pInfo==0 ){
+        assert( !ExprHasProperty(pExpr, EP_IntValue) );
+        sqlite3ErrorMsg(pParse, "misuse of aggregate: %s()", pExpr->u.zToken);
+      }else{
+        inReg = pInfo->aFunc[pExpr->iAgg].iMem;
+      }
+      break;
+    }
+    case TK_CONST_FUNC:
+    case TK_FUNCTION: {
+      ExprList *pFarg;       /* List of function arguments */
+      int nFarg;             /* Number of function arguments */
+      FuncDef *pDef;         /* The function definition object */
+      int nId;               /* Length of the function name in bytes */
+      const char *zId;       /* The function name */
+      int constMask = 0;     /* Mask of function arguments that are constant */
+      int i;                 /* Loop counter */
+      u8 enc = ENC(db);      /* The text encoding used by this database */
+      CollSeq *pColl = 0;    /* A collating sequence */
+
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      testcase( op==TK_CONST_FUNC );
+      testcase( op==TK_FUNCTION );
+      if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ){
+        pFarg = 0;
+      }else{
+        pFarg = pExpr->x.pList;
+      }
+      nFarg = pFarg ? pFarg->nExpr : 0;
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      zId = pExpr->u.zToken;
+      nId = sqlite3Strlen30(zId);
+      pDef = sqlite3FindFunction(db, zId, nId, nFarg, enc, 0);
+      if( pDef==0 ){
+        sqlite3ErrorMsg(pParse, "unknown function: %.*s()", nId, zId);
+        break;
+      }
+      if( pFarg ){
+        r1 = sqlite3GetTempRange(pParse, nFarg);
+        sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
+        sqlite3ExprCodeExprList(pParse, pFarg, r1, 1);
+        sqlite3ExprCachePop(pParse, 1);   /* Ticket 2ea2425d34be */
+      }else{
+        r1 = 0;
+      }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+      /* Possibly overload the function if the first argument is
+      ** a virtual table column.
+      **
+      ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
+      ** second argument, not the first, as the argument to test to
+      ** see if it is a column in a virtual table.  This is done because
+      ** the left operand of infix functions (the operand we want to
+      ** control overloading) ends up as the second argument to the
+      ** function.  The expression "A glob B" is equivalent to 
+      ** "glob(B,A).  We want to use the A in "A glob B" to test
+      ** for function overloading.  But we use the B term in "glob(B,A)".
+      */
+      if( nFarg>=2 && (pExpr->flags & EP_InfixFunc) ){
+        pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[1].pExpr);
+      }else if( nFarg>0 ){
+        pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr);
+      }
+#endif
+      for(i=0; i<nFarg; i++){
+        if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){
+          constMask |= (1<<i);
+        }
+        if( (pDef->flags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
+          pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr);
+        }
+      }
+      if( pDef->flags & SQLITE_FUNC_NEEDCOLL ){
+        if( !pColl ) pColl = db->pDfltColl; 
+        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
+      }
+      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
+                        (char*)pDef, P4_FUNCDEF);
+      sqlite3VdbeChangeP5(v, (u8)nFarg);
+      if( nFarg ){
+        sqlite3ReleaseTempRange(pParse, r1, nFarg);
+      }
+      sqlite3ExprCacheAffinityChange(pParse, r1, nFarg);
+      break;
+    }
+#ifndef SQLITE_OMIT_SUBQUERY
+    case TK_EXISTS:
+    case TK_SELECT: {
+      testcase( op==TK_EXISTS );
+      testcase( op==TK_SELECT );
+      sqlite3CodeSubselect(pParse, pExpr, 0, 0);
+      inReg = pExpr->iColumn;
+      break;
+    }
+    case TK_IN: {
+      int rNotFound = 0;
+      int rMayHaveNull = 0;
+      int j2, j3, j4, j5;
+      char affinity;
+      int eType;
 
+      VdbeNoopComment((v, "begin IN expr r%d", target));
+      eType = sqlite3FindInIndex(pParse, pExpr, &rMayHaveNull);
+      if( rMayHaveNull ){
+        rNotFound = ++pParse->nMem;
+      }
 
-/*
-** Locate and return an entry from the db.aCollSeq hash table. If the entry
-** specified by zName and nName is not found and parameter 'create' is
-** true, then create a new entry. Otherwise return NULL.
-**
-** Each pointer stored in the sqlite3.aCollSeq hash table contains an
-** array of three CollSeq structures. The first is the collation sequence
-** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
-**
-** Stored immediately after the three collation sequences is a copy of
-** the collation sequence name. A pointer to this string is stored in
-** each collation sequence structure.
-*/
-static CollSeq *findCollSeqEntry(
-  sqlite3 *db,
-  const char *zName,
-  int nName,
-  int create
-){
-  CollSeq *pColl;
-  if( nName<0 ) nName = strlen(zName);
-  pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
+      /* Figure out the affinity to use to create a key from the results
+      ** of the expression. affinityStr stores a static string suitable for
+      ** P4 of OP_MakeRecord.
+      */
+      affinity = comparisonAffinity(pExpr);
 
-  if( 0==pColl && create ){
-    pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
-    if( pColl ){
-      CollSeq *pDel = 0;
-      pColl[0].zName = (char*)&pColl[3];
-      pColl[0].enc = SQLITE_UTF8;
-      pColl[1].zName = (char*)&pColl[3];
-      pColl[1].enc = SQLITE_UTF16LE;
-      pColl[2].zName = (char*)&pColl[3];
-      pColl[2].enc = SQLITE_UTF16BE;
-      memcpy(pColl[0].zName, zName, nName);
-      pColl[0].zName[nName] = 0;
-      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);
 
-      /* If a malloc() failure occured in sqlite3HashInsert(), it will 
-      ** return the pColl pointer to be deleted (because it wasn't added
-      ** to the hash table).
+      /* Code the <expr> from "<expr> IN (...)". The temporary table
+      ** pExpr->iTable contains the values that make up the (...) set.
       */
-      assert( pDel==0 || pDel==pColl );
-      if( pDel!=0 ){
-        db->mallocFailed = 1;
-        sqlite3_free(pDel);
-        pColl = 0;
+      sqlite3ExprCachePush(pParse);
+      sqlite3ExprCode(pParse, pExpr->pLeft, target);
+      j2 = sqlite3VdbeAddOp1(v, OP_IsNull, target);
+      if( eType==IN_INDEX_ROWID ){
+        j3 = sqlite3VdbeAddOp1(v, OP_MustBeInt, target);
+        j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, target);
+        sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+        j5 = sqlite3VdbeAddOp0(v, OP_Goto);
+        sqlite3VdbeJumpHere(v, j3);
+        sqlite3VdbeJumpHere(v, j4);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
+      }else{
+        r2 = regFree2 = sqlite3GetTempReg(pParse);
+
+        /* Create a record and test for set membership. If the set contains
+        ** the value, then jump to the end of the test code. The target
+        ** register still contains the true (1) value written to it earlier.
+        */
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, target, 1, r2, &affinity, 1);
+        sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+        j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
+
+        /* If the set membership test fails, then the result of the 
+        ** "x IN (...)" expression must be either 0 or NULL. If the set
+        ** contains no NULL values, then the result is 0. If the set 
+        ** contains one or more NULL values, then the result of the
+        ** expression is also NULL.
+        */
+        if( rNotFound==0 ){
+          /* This branch runs if it is known at compile time (now) that 
+          ** the set contains no NULL values. This happens as the result
+          ** of a "NOT NULL" constraint in the database schema. No need
+          ** to test the data structure at runtime in this case.
+          */
+          sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
+        }else{
+          /* This block populates the rNotFound register with either NULL
+          ** or 0 (an integer value). If the data structure contains one
+          ** or more NULLs, then set rNotFound to NULL. Otherwise, set it
+          ** to 0. If register rMayHaveNull is already set to some value
+          ** other than NULL, then the test has already been run and 
+          ** rNotFound is already populated.
+          */
+          static const char nullRecord[] = { 0x02, 0x00 };
+          j3 = sqlite3VdbeAddOp1(v, OP_NotNull, rMayHaveNull);
+          sqlite3VdbeAddOp2(v, OP_Null, 0, rNotFound);
+          sqlite3VdbeAddOp4(v, OP_Blob, 2, rMayHaveNull, 0, 
+                             nullRecord, P4_STATIC);
+          j4 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, rMayHaveNull);
+          sqlite3VdbeAddOp2(v, OP_Integer, 0, rNotFound);
+          sqlite3VdbeJumpHere(v, j4);
+          sqlite3VdbeJumpHere(v, j3);
+
+          /* Copy the value of register rNotFound (which is either NULL or 0)
+          ** into the target register. This will be the result of the
+          ** expression.
+          */
+          sqlite3VdbeAddOp2(v, OP_Copy, rNotFound, target);
+        }
       }
+      sqlite3VdbeJumpHere(v, j2);
+      sqlite3VdbeJumpHere(v, j5);
+      sqlite3ExprCachePop(pParse, 1);
+      VdbeComment((v, "end IN expr r%d", target));
+      break;
     }
-  }
-  return pColl;
-}
-
-/*
-** Parameter zName points to a UTF-8 encoded string nName bytes long.
-** Return the CollSeq* pointer for the collation sequence named zName
-** for the encoding 'enc' from the database 'db'.
-**
-** If the entry specified is not found and 'create' is true, then create a
-** new entry.  Otherwise return NULL.
-**
-** A separate function sqlite3LocateCollSeq() is a wrapper around
-** this routine.  sqlite3LocateCollSeq() invokes the collation factory
-** if necessary and generates an error message if the collating sequence
-** cannot be found.
-*/
-SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(
-  sqlite3 *db,
-  u8 enc,
-  const char *zName,
-  int nName,
-  int create
-){
-  CollSeq *pColl;
-  if( zName ){
-    pColl = findCollSeqEntry(db, zName, nName, create);
-  }else{
-    pColl = db->pDfltColl;
-  }
-  assert( SQLITE_UTF8==1 && SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
-  assert( enc>=SQLITE_UTF8 && enc<=SQLITE_UTF16BE );
-  if( pColl ) pColl += enc-1;
-  return pColl;
-}
+#endif
+    /*
+    **    x BETWEEN y AND z
+    **
+    ** This is equivalent to
+    **
+    **    x>=y AND x<=z
+    **
+    ** X is stored in pExpr->pLeft.
+    ** Y is stored in pExpr->pList->a[0].pExpr.
+    ** Z is stored in pExpr->pList->a[1].pExpr.
+    */
+    case TK_BETWEEN: {
+      Expr *pLeft = pExpr->pLeft;
+      struct ExprList_item *pLItem = pExpr->x.pList->a;
+      Expr *pRight = pLItem->pExpr;
 
-/*
-** Locate a user function given a name, a number of arguments and a flag
-** indicating whether the function prefers UTF-16 over UTF-8.  Return a
-** pointer to the FuncDef structure that defines that function, or return
-** NULL if the function does not exist.
-**
-** If the createFlag argument is true, then a new (blank) FuncDef
-** structure is created and liked into the "db" structure if a
-** no matching function previously existed.  When createFlag is true
-** and the nArg parameter is -1, then only a function that accepts
-** any number of arguments will be returned.
-**
-** If createFlag is false and nArg is -1, then the first valid
-** function found is returned.  A function is valid if either xFunc
-** or xStep is non-zero.
-**
-** If createFlag is false, then a function with the required name and
-** number of arguments may be returned even if the eTextRep flag does not
-** match that requested.
-*/
-SQLITE_PRIVATE FuncDef *sqlite3FindFunction(
-  sqlite3 *db,       /* An open database */
-  const char *zName, /* Name of the function.  Not null-terminated */
-  int nName,         /* Number of characters in the name */
-  int nArg,          /* Number of arguments.  -1 means any number */
-  u8 enc,            /* Preferred text encoding */
-  int createFlag     /* Create new entry if true and does not otherwise exist */
-){
-  FuncDef *p;         /* Iterator variable */
-  FuncDef *pFirst;    /* First function with this name */
-  FuncDef *pBest = 0; /* Best match found so far */
-  int bestmatch = 0;  
+      codeCompareOperands(pParse, pLeft, &r1, &regFree1,
+                                  pRight, &r2, &regFree2);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      r3 = sqlite3GetTempReg(pParse);
+      r4 = sqlite3GetTempReg(pParse);
+      codeCompare(pParse, pLeft, pRight, OP_Ge,
+                  r1, r2, r3, SQLITE_STOREP2);
+      pLItem++;
+      pRight = pLItem->pExpr;
+      sqlite3ReleaseTempReg(pParse, regFree2);
+      r2 = sqlite3ExprCodeTemp(pParse, pRight, &regFree2);
+      testcase( regFree2==0 );
+      codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
+      sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
+      sqlite3ReleaseTempReg(pParse, r3);
+      sqlite3ReleaseTempReg(pParse, r4);
+      break;
+    }
+    case TK_UPLUS: {
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+      break;
+    }
 
+    case TK_TRIGGER: {
+      /* If the opcode is TK_TRIGGER, then the expression is a reference
+      ** to a column in the new.* or old.* pseudo-tables available to
+      ** trigger programs. In this case Expr.iTable is set to 1 for the
+      ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
+      ** is set to the column of the pseudo-table to read, or to -1 to
+      ** read the rowid field.
+      **
+      ** The expression is implemented using an OP_Param opcode. The p1
+      ** parameter is set to 0 for an old.rowid reference, or to (i+1)
+      ** to reference another column of the old.* pseudo-table, where 
+      ** i is the index of the column. For a new.rowid reference, p1 is
+      ** set to (n+1), where n is the number of columns in each pseudo-table.
+      ** For a reference to any other column in the new.* pseudo-table, p1
+      ** is set to (n+2+i), where n and i are as defined previously. For
+      ** example, if the table on which triggers are being fired is
+      ** declared as:
+      **
+      **   CREATE TABLE t1(a, b);
+      **
+      ** Then p1 is interpreted as follows:
+      **
+      **   p1==0   ->    old.rowid     p1==3   ->    new.rowid
+      **   p1==1   ->    old.a         p1==4   ->    new.a
+      **   p1==2   ->    old.b         p1==5   ->    new.b       
+      */
+      Table *pTab = pExpr->pTab;
+      int p1 = pExpr->iTable * (pTab->nCol+1) + 1 + pExpr->iColumn;
+
+      assert( pExpr->iTable==0 || pExpr->iTable==1 );
+      assert( pExpr->iColumn>=-1 && pExpr->iColumn<pTab->nCol );
+      assert( pTab->iPKey<0 || pExpr->iColumn!=pTab->iPKey );
+      assert( p1>=0 && p1<(pTab->nCol*2+2) );
+
+      sqlite3VdbeAddOp2(v, OP_Param, p1, target);
+      VdbeComment((v, "%s.%s -> $%d",
+        (pExpr->iTable ? "new" : "old"),
+        (pExpr->iColumn<0 ? "rowid" : pExpr->pTab->aCol[pExpr->iColumn].zName),
+        target
+      ));
+
+      /* If the column has REAL affinity, it may currently be stored as an
+      ** integer. Use OP_RealAffinity to make sure it is really real.  */
+      if( pExpr->iColumn>=0 
+       && pTab->aCol[pExpr->iColumn].affinity==SQLITE_AFF_REAL
+      ){
+        sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
+      }
+      break;
+    }
 
-  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
-  if( nArg<-1 ) nArg = -1;
 
-  pFirst = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName);
-  for(p=pFirst; p; p=p->pNext){
-    /* During the search for the best function definition, bestmatch is set
-    ** as follows to indicate the quality of the match with the definition
-    ** pointed to by pBest:
+    /*
+    ** Form A:
+    **   CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
+    **
+    ** Form B:
+    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
+    **
+    ** Form A is can be transformed into the equivalent form B as follows:
+    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
+    **        WHEN x=eN THEN rN ELSE y END
     **
-    ** 0: pBest is NULL. No match has been found.
-    ** 1: A variable arguments function that prefers UTF-8 when a UTF-16
-    **    encoding is requested, or vice versa.
-    ** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
-    **    requested, or vice versa.
-    ** 3: A variable arguments function using the same text encoding.
-    ** 4: A function with the exact number of arguments requested that
-    **    prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
-    ** 5: A function with the exact number of arguments requested that
-    **    prefers UTF-16LE when UTF-16BE is requested, or vice versa.
-    ** 6: An exact match.
+    ** X (if it exists) is in pExpr->pLeft.
+    ** Y is in pExpr->pRight.  The Y is also optional.  If there is no
+    ** ELSE clause and no other term matches, then the result of the
+    ** exprssion is NULL.
+    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
     **
-    ** A larger value of 'matchqual' indicates a more desirable match.
+    ** The result of the expression is the Ri for the first matching Ei,
+    ** or if there is no matching Ei, the ELSE term Y, or if there is
+    ** no ELSE term, NULL.
     */
-    if( p->nArg==-1 || p->nArg==nArg || nArg==-1 ){
-      int match = 1;          /* Quality of this match */
-      if( p->nArg==nArg || nArg==-1 ){
-        match = 4;
-      }
-      if( enc==p->iPrefEnc ){
-        match += 2;
+    default: assert( op==TK_CASE ); {
+      int endLabel;                     /* GOTO label for end of CASE stmt */
+      int nextCase;                     /* GOTO label for next WHEN clause */
+      int nExpr;                        /* 2x number of WHEN terms */
+      int i;                            /* Loop counter */
+      ExprList *pEList;                 /* List of WHEN terms */
+      struct ExprList_item *aListelem;  /* Array of WHEN terms */
+      Expr opCompare;                   /* The X==Ei expression */
+      Expr cacheX;                      /* Cached expression X */
+      Expr *pX;                         /* The X expression */
+      Expr *pTest = 0;                  /* X==Ei (form A) or just Ei (form B) */
+      VVA_ONLY( int iCacheLevel = pParse->iCacheLevel; )
+
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList );
+      assert((pExpr->x.pList->nExpr % 2) == 0);
+      assert(pExpr->x.pList->nExpr > 0);
+      pEList = pExpr->x.pList;
+      aListelem = pEList->a;
+      nExpr = pEList->nExpr;
+      endLabel = sqlite3VdbeMakeLabel(v);
+      if( (pX = pExpr->pLeft)!=0 ){
+        cacheX = *pX;
+        testcase( pX->op==TK_COLUMN );
+        testcase( pX->op==TK_REGISTER );
+        cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, &regFree1);
+        testcase( regFree1==0 );
+        cacheX.op = TK_REGISTER;
+        opCompare.op = TK_EQ;
+        opCompare.pLeft = &cacheX;
+        pTest = &opCompare;
       }
-      else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
-               (enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
-        match += 1;
+      for(i=0; i<nExpr; i=i+2){
+        sqlite3ExprCachePush(pParse);
+        if( pX ){
+          assert( pTest!=0 );
+          opCompare.pRight = aListelem[i].pExpr;
+        }else{
+          pTest = aListelem[i].pExpr;
+        }
+        nextCase = sqlite3VdbeMakeLabel(v);
+        testcase( pTest->op==TK_COLUMN );
+        sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
+        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
+        testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
+        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
+        sqlite3ExprCachePop(pParse, 1);
+        sqlite3VdbeResolveLabel(v, nextCase);
       }
-
-      if( match>bestmatch ){
-        pBest = p;
-        bestmatch = match;
+      if( pExpr->pRight ){
+        sqlite3ExprCachePush(pParse);
+        sqlite3ExprCode(pParse, pExpr->pRight, target);
+        sqlite3ExprCachePop(pParse, 1);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
       }
+      assert( db->mallocFailed || pParse->nErr>0 
+           || pParse->iCacheLevel==iCacheLevel );
+      sqlite3VdbeResolveLabel(v, endLabel);
+      break;
     }
-  }
+#ifndef SQLITE_OMIT_TRIGGER
+    case TK_RAISE: {
+      assert( pExpr->affinity==OE_Rollback 
+           || pExpr->affinity==OE_Abort
+           || pExpr->affinity==OE_Fail
+           || pExpr->affinity==OE_Ignore
+      );
+      if( !pParse->pTriggerTab ){
+        sqlite3ErrorMsg(pParse,
+                       "RAISE() may only be used within a trigger-program");
+        return 0;
+      }
+      if( pExpr->affinity==OE_Abort ){
+        sqlite3MayAbort(pParse);
+      }
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      if( pExpr->affinity==OE_Ignore ){
+        sqlite3VdbeAddOp4(
+            v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0);
+      }else{
+        sqlite3HaltConstraint(pParse, pExpr->affinity, pExpr->u.zToken, 0);
+      }
 
-  /* If the createFlag parameter is true, and the seach did not reveal an
-  ** exact match for the name, number of arguments and encoding, then add a
-  ** new entry to the hash table and return it.
-  */
-  if( createFlag && bestmatch<6 && 
-      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName))!=0 ){
-    pBest->nArg = nArg;
-    pBest->pNext = pFirst;
-    pBest->iPrefEnc = enc;
-    memcpy(pBest->zName, zName, nName);
-    pBest->zName[nName] = 0;
-    if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
-      db->mallocFailed = 1;
-      sqlite3_free(pBest);
-      return 0;
+      break;
     }
+#endif
   }
+  sqlite3ReleaseTempReg(pParse, regFree1);
+  sqlite3ReleaseTempReg(pParse, regFree2);
+  return inReg;
+}
 
-  if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
-    return pBest;
+/*
+** Generate code to evaluate an expression and store the results
+** into a register.  Return the register number where the results
+** are stored.
+**
+** If the register is a temporary register that can be deallocated,
+** then write its number into *pReg.  If the result register is not
+** a temporary, then set *pReg to zero.
+*/
+SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
+  int r1 = sqlite3GetTempReg(pParse);
+  int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
+  if( r2==r1 ){
+    *pReg = r1;
+  }else{
+    sqlite3ReleaseTempReg(pParse, r1);
+    *pReg = 0;
   }
-  return 0;
+  return r2;
 }
 
 /*
-** Free all resources held by the schema structure. The void* argument points
-** at a Schema struct. This function does not call sqlite3_free() on the 
-** pointer itself, it just cleans up subsiduary resources (i.e. the contents
-** of the schema hash tables).
-*/
-SQLITE_PRIVATE void sqlite3SchemaFree(void *p){
-  Hash temp1;
-  Hash temp2;
-  HashElem *pElem;
-  Schema *pSchema = (Schema *)p;
+** Generate code that will evaluate expression pExpr and store the
+** results in register target.  The results are guaranteed to appear
+** in register target.
+*/
+SQLITE_PRIVATE int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
+  int inReg;
 
-  temp1 = pSchema->tblHash;
-  temp2 = pSchema->trigHash;
-  sqlite3HashInit(&pSchema->trigHash, SQLITE_HASH_STRING, 0);
-  sqlite3HashClear(&pSchema->aFKey);
-  sqlite3HashClear(&pSchema->idxHash);
-  for(pElem=sqliteHashFirst(&temp2); pElem; pElem=sqliteHashNext(pElem)){
-    sqlite3DeleteTrigger((Trigger*)sqliteHashData(pElem));
-  }
-  sqlite3HashClear(&temp2);
-  sqlite3HashInit(&pSchema->tblHash, SQLITE_HASH_STRING, 0);
-  for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
-    Table *pTab = sqliteHashData(pElem);
-    sqlite3DeleteTable(pTab);
+  assert( target>0 && target<=pParse->nMem );
+  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+  assert( pParse->pVdbe || pParse->db->mallocFailed );
+  if( inReg!=target && pParse->pVdbe ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
   }
-  sqlite3HashClear(&temp1);
-  pSchema->pSeqTab = 0;
-  pSchema->flags &= ~DB_SchemaLoaded;
+  return target;
 }
 
 /*
-** Find and return the schema associated with a BTree.  Create
-** a new one if necessary.
+** Generate code that evalutes the given expression and puts the result
+** in register target.
+**
+** Also make a copy of the expression results into another "cache" register
+** and modify the expression so that the next time it is evaluated,
+** the result is a copy of the cache register.
+**
+** This routine is used for expressions that are used multiple 
+** times.  They are evaluated once and the results of the expression
+** are reused.
 */
-SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
-  Schema * p;
-  if( pBt ){
-    p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaFree);
-  }else{
-    p = (Schema *)sqlite3MallocZero(sizeof(Schema));
-  }
-  if( !p ){
-    db->mallocFailed = 1;
-  }else if ( 0==p->file_format ){
-    sqlite3HashInit(&p->tblHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->idxHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->trigHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->aFKey, SQLITE_HASH_STRING, 1);
-    p->enc = SQLITE_UTF8;
+SQLITE_PRIVATE int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
+  Vdbe *v = pParse->pVdbe;
+  int inReg;
+  inReg = sqlite3ExprCode(pParse, pExpr, target);
+  assert( target>0 );
+  /* This routine is called for terms to INSERT or UPDATE.  And the only
+  ** other place where expressions can be converted into TK_REGISTER is
+  ** in WHERE clause processing.  So as currently implemented, there is
+  ** no way for a TK_REGISTER to exist here.  But it seems prudent to
+  ** keep the ALWAYS() in case the conditions above change with future
+  ** modifications or enhancements. */
+  if( ALWAYS(pExpr->op!=TK_REGISTER) ){  
+    int iMem;
+    iMem = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
+    pExpr->iTable = iMem;
+    pExpr->op = TK_REGISTER;
   }
-  return p;
+  return inReg;
 }
 
-/************** End of callback.c ********************************************/
-/************** Begin file delete.c ******************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Return TRUE if pExpr is an constant expression that is appropriate
+** for factoring out of a loop.  Appropriate expressions are:
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+**    *  Any expression that evaluates to two or more opcodes.
 **
-*************************************************************************
-** This file contains C code routines that are called by the parser
-** in order to generate code for DELETE FROM statements.
+**    *  Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null, 
+**       or OP_Variable that does not need to be placed in a 
+**       specific register.
 **
-** $Id: delete.c,v 1.169 2008/04/28 18:46:43 drh Exp $
-*/
-
-/*
-** Look up every table that is named in pSrc.  If any table is not found,
-** add an error message to pParse->zErrMsg and return NULL.  If all tables
-** are found, return a pointer to the last table.
+** There is no point in factoring out single-instruction constant
+** expressions that need to be placed in a particular register.  
+** We could factor them out, but then we would end up adding an
+** OP_SCopy instruction to move the value into the correct register
+** later.  We might as well just use the original instruction and
+** avoid the OP_SCopy.
 */
-SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
-  Table *pTab = 0;
-  int i;
-  struct SrcList_item *pItem;
-  for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){
-    pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
-    sqlite3DeleteTable(pItem->pTab);
-    pItem->pTab = pTab;
-    if( pTab ){
-      pTab->nRef++;
+static int isAppropriateForFactoring(Expr *p){
+  if( !sqlite3ExprIsConstantNotJoin(p) ){
+    return 0;  /* Only constant expressions are appropriate for factoring */
+  }
+  if( (p->flags & EP_FixedDest)==0 ){
+    return 1;  /* Any constant without a fixed destination is appropriate */
+  }
+  while( p->op==TK_UPLUS ) p = p->pLeft;
+  switch( p->op ){
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+    case TK_BLOB:
+#endif
+    case TK_VARIABLE:
+    case TK_INTEGER:
+    case TK_FLOAT:
+    case TK_NULL:
+    case TK_STRING: {
+      testcase( p->op==TK_BLOB );
+      testcase( p->op==TK_VARIABLE );
+      testcase( p->op==TK_INTEGER );
+      testcase( p->op==TK_FLOAT );
+      testcase( p->op==TK_NULL );
+      testcase( p->op==TK_STRING );
+      /* Single-instruction constants with a fixed destination are
+      ** better done in-line.  If we factor them, they will just end
+      ** up generating an OP_SCopy to move the value to the destination
+      ** register. */
+      return 0;
+    }
+    case TK_UMINUS: {
+      if( p->pLeft->op==TK_FLOAT || p->pLeft->op==TK_INTEGER ){
+        return 0;
+      }
+      break;
+    }
+    default: {
+      break;
     }
   }
-  return pTab;
+  return 1;
 }
 
 /*
-** Check to make sure the given table is writable.  If it is not
-** writable, generate an error message and return 1.  If it is
-** writable return 0;
+** If pExpr is a constant expression that is appropriate for
+** factoring out of a loop, then evaluate the expression
+** into a register and convert the expression into a TK_REGISTER
+** expression.
 */
-SQLITE_PRIVATE int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
-  if( (pTab->readOnly && (pParse->db->flags & SQLITE_WriteSchema)==0
-        && pParse->nested==0) 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      || (pTab->pMod && pTab->pMod->pModule->xUpdate==0)
-#endif
-  ){
-    sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
-    return 1;
+static int evalConstExpr(Walker *pWalker, Expr *pExpr){
+  Parse *pParse = pWalker->pParse;
+  switch( pExpr->op ){
+    case TK_REGISTER: {
+      return WRC_Prune;
+    }
+    case TK_FUNCTION:
+    case TK_AGG_FUNCTION:
+    case TK_CONST_FUNC: {
+      /* The arguments to a function have a fixed destination.
+      ** Mark them this way to avoid generated unneeded OP_SCopy
+      ** instructions. 
+      */
+      ExprList *pList = pExpr->x.pList;
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      if( pList ){
+        int i = pList->nExpr;
+        struct ExprList_item *pItem = pList->a;
+        for(; i>0; i--, pItem++){
+          if( ALWAYS(pItem->pExpr) ) pItem->pExpr->flags |= EP_FixedDest;
+        }
+      }
+      break;
+    }
   }
-#ifndef SQLITE_OMIT_VIEW
-  if( !viewOk && pTab->pSelect ){
-    sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
-    return 1;
+  if( isAppropriateForFactoring(pExpr) ){
+    int r1 = ++pParse->nMem;
+    int r2;
+    r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
+    if( NEVER(r1!=r2) ) sqlite3ReleaseTempReg(pParse, r1);
+    pExpr->op2 = pExpr->op;
+    pExpr->op = TK_REGISTER;
+    pExpr->iTable = r2;
+    return WRC_Prune;
   }
-#endif
-  return 0;
+  return WRC_Continue;
 }
 
 /*
-** Generate code that will open a table for reading.
+** Preevaluate constant subexpressions within pExpr and store the
+** results in registers.  Modify pExpr so that the constant subexpresions
+** are TK_REGISTER opcodes that refer to the precomputed values.
 */
-SQLITE_PRIVATE void sqlite3OpenTable(
-  Parse *p,       /* Generate code into this VDBE */
-  int iCur,       /* The cursor number of the table */
-  int iDb,        /* The database index in sqlite3.aDb[] */
-  Table *pTab,    /* The table to be opened */
-  int opcode      /* OP_OpenRead or OP_OpenWrite */
-){
-  Vdbe *v;
-  if( IsVirtual(pTab) ) return;
-  v = sqlite3GetVdbe(p);
-  assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
-  sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite), pTab->zName);
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
-  sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
-  VdbeComment((v, "%s", pTab->zName));
+SQLITE_PRIVATE void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
+  Walker w;
+  w.xExprCallback = evalConstExpr;
+  w.xSelectCallback = 0;
+  w.pParse = pParse;
+  sqlite3WalkExpr(&w, pExpr);
 }
 
 
-#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
 /*
-** Evaluate a view and store its result in an ephemeral table.  The
-** pWhere argument is an optional WHERE clause that restricts the
-** set of rows in the view that are to be added to the ephemeral table.
+** Generate code that pushes the value of every element of the given
+** expression list into a sequence of registers beginning at target.
+**
+** Return the number of elements evaluated.
 */
-SQLITE_PRIVATE void sqlite3MaterializeView(
-  Parse *pParse,       /* Parsing context */
-  Select *pView,       /* View definition */
-  Expr *pWhere,        /* Optional WHERE clause to be added */
-  int iCur             /* Cursor number for ephemerial table */
+SQLITE_PRIVATE int sqlite3ExprCodeExprList(
+  Parse *pParse,     /* Parsing context */
+  ExprList *pList,   /* The expression list to be coded */
+  int target,        /* Where to write results */
+  int doHardCopy     /* Make a hard copy of every element */
 ){
-  SelectDest dest;
-  Select *pDup;
-  sqlite3 *db = pParse->db;
-
-  pDup = sqlite3SelectDup(db, pView);
-  if( pWhere ){
-    SrcList *pFrom;
-    
-    pWhere = sqlite3ExprDup(db, pWhere);
-    pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
-    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+  struct ExprList_item *pItem;
+  int i, n;
+  assert( pList!=0 );
+  assert( target>0 );
+  n = pList->nExpr;
+  for(pItem=pList->a, i=0; i<n; i++, pItem++){
+    if( pItem->iAlias ){
+      int iReg = codeAlias(pParse, pItem->iAlias, pItem->pExpr, target+i);
+      Vdbe *v = sqlite3GetVdbe(pParse);
+      if( iReg!=target+i ){
+        sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target+i);
+      }
+    }else{
+      sqlite3ExprCode(pParse, pItem->pExpr, target+i);
+    }
+    if( doHardCopy && !pParse->db->mallocFailed ){
+      sqlite3ExprHardCopy(pParse, target, n);
+    }
   }
-  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
-  sqlite3Select(pParse, pDup, &dest, 0, 0, 0, 0);
-  sqlite3SelectDelete(pDup);
+  return n;
 }
-#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
-
 
 /*
-** Generate code for a DELETE FROM statement.
+** Generate code for a boolean expression such that a jump is made
+** to the label "dest" if the expression is true but execution
+** continues straight thru if the expression is false.
 **
-**     DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
-**                 \________/       \________________/
-**                  pTabList              pWhere
+** If the expression evaluates to NULL (neither true nor false), then
+** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL.
+**
+** This code depends on the fact that certain token values (ex: TK_EQ)
+** are the same as opcode values (ex: OP_Eq) that implement the corresponding
+** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in
+** the make process cause these values to align.  Assert()s in the code
+** below verify that the numbers are aligned correctly.
 */
-SQLITE_PRIVATE void sqlite3DeleteFrom(
-  Parse *pParse,         /* The parser context */
-  SrcList *pTabList,     /* The table from which we should delete things */
-  Expr *pWhere           /* The WHERE clause.  May be null */
-){
-  Vdbe *v;               /* The virtual database engine */
-  Table *pTab;           /* The table from which records will be deleted */
-  const char *zDb;       /* Name of database holding pTab */
-  int end, addr = 0;     /* A couple addresses of generated code */
-  int i;                 /* Loop counter */
-  WhereInfo *pWInfo;     /* Information about the WHERE clause */
-  Index *pIdx;           /* For looping over indices of the table */
-  int iCur;              /* VDBE Cursor number for pTab */
-  sqlite3 *db;           /* Main database structure */
-  AuthContext sContext;  /* Authorization context */
-  int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */
-  NameContext sNC;       /* Name context to resolve expressions in */
-  int iDb;               /* Database number */
-  int memCnt = 0;        /* Memory cell used for change counting */
-
-#ifndef SQLITE_OMIT_TRIGGER
-  int isView;                  /* True if attempting to delete from a view */
-  int triggers_exist = 0;      /* True if any triggers exist */
-#endif
-  int iBeginAfterTrigger;      /* Address of after trigger program */
-  int iEndAfterTrigger;        /* Exit of after trigger program */
-  int iBeginBeforeTrigger;     /* Address of before trigger program */
-  int iEndBeforeTrigger;       /* Exit of before trigger program */
-  u32 old_col_mask = 0;        /* Mask of OLD.* columns in use */
-
-  sContext.pParse = 0;
-  db = pParse->db;
-  if( pParse->nErr || db->mallocFailed ){
-    goto delete_from_cleanup;
-  }
-  assert( pTabList->nSrc==1 );
-
-  /* Locate the table which we want to delete.  This table has to be
-  ** put in an SrcList structure because some of the subroutines we
-  ** will be calling are designed to work with multiple tables and expect
-  ** an SrcList* parameter instead of just a Table* parameter.
-  */
-  pTab = sqlite3SrcListLookup(pParse, pTabList);
-  if( pTab==0 )  goto delete_from_cleanup;
-
-  /* Figure out if we have any triggers and if the table being
-  ** deleted from is a view
-  */
-#ifndef SQLITE_OMIT_TRIGGER
-  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0);
-  isView = pTab->pSelect!=0;
-#else
-# define triggers_exist 0
-# define isView 0
-#endif
-#ifdef SQLITE_OMIT_VIEW
-# undef isView
-# define isView 0
-#endif
-
-  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
-    goto delete_from_cleanup;
-  }
-  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-  assert( iDb<db->nDb );
-  zDb = db->aDb[iDb].zName;
-  if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
-    goto delete_from_cleanup;
-  }
-
-  /* If pTab is really a view, make sure it has been initialized.
-  */
-  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-    goto delete_from_cleanup;
-  }
-
-  /* Allocate a cursor used to store the old.* data for a trigger.
-  */
-  if( triggers_exist ){ 
-    oldIdx = pParse->nTab++;
-  }
-
-  /* Assign  cursor number to the table and all its indices.
-  */
-  assert( pTabList->nSrc==1 );
-  iCur = pTabList->a[0].iCursor = pParse->nTab++;
-  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-    pParse->nTab++;
-  }
-
-  /* Start the view context
-  */
-  if( isView ){
-    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
-  }
-
-  /* Begin generating code.
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ){
-    goto delete_from_cleanup;
-  }
-  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
-  sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);
-
-  if( triggers_exist ){
-    int orconf = ((pParse->trigStack)?pParse->trigStack->orconf:OE_Default);
-    int iGoto = sqlite3VdbeAddOp0(v, OP_Goto);
-    addr = sqlite3VdbeMakeLabel(v);
-
-    iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
-    (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
-        -1, oldIdx, orconf, addr, &old_col_mask, 0);
-    iEndBeforeTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
-
-    iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
-    (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
-        oldIdx, orconf, addr, &old_col_mask, 0);
-    iEndAfterTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
-
-    sqlite3VdbeJumpHere(v, iGoto);
-  }
-
-  /* If we are trying to delete from a view, realize that view into
-  ** a ephemeral table.
-  */
-  if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
-  }
-
-  /* Resolve the column names in the WHERE clause.
-  */
-  memset(&sNC, 0, sizeof(sNC));
-  sNC.pParse = pParse;
-  sNC.pSrcList = pTabList;
-  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
-    goto delete_from_cleanup;
-  }
-
-  /* Initialize the counter of the number of rows deleted, if
-  ** we are counting rows.
-  */
-  if( db->flags & SQLITE_CountRows ){
-    memCnt = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
-  }
+SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
+  Vdbe *v = pParse->pVdbe;
+  int op = 0;
+  int regFree1 = 0;
+  int regFree2 = 0;
+  int r1, r2;
 
-  /* Special case: A DELETE without a WHERE clause deletes everything.
-  ** It is easier just to erase the whole table.  Note, however, that
-  ** this means that the row change count will be incorrect.
-  */
-  if( pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){
-    if( db->flags & SQLITE_CountRows ){
-      /* If counting rows deleted, just count the total number of
-      ** entries in the table. */
-      int addr2;
-      if( !isView ){
-        sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
-      }
-      sqlite3VdbeAddOp2(v, OP_Rewind, iCur, sqlite3VdbeCurrentAddr(v)+2);
-      addr2 = sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
-      sqlite3VdbeAddOp2(v, OP_Next, iCur, addr2);
-      sqlite3VdbeAddOp1(v, OP_Close, iCur);
+  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
+  if( NEVER(v==0) )     return;  /* Existance of VDBE checked by caller */
+  if( NEVER(pExpr==0) ) return;  /* No way this can happen */
+  op = pExpr->op;
+  switch( op ){
+    case TK_AND: {
+      int d2 = sqlite3VdbeMakeLabel(v);
+      testcase( jumpIfNull==0 );
+      sqlite3ExprCachePush(pParse);
+      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
+      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+      sqlite3VdbeResolveLabel(v, d2);
+      sqlite3ExprCachePop(pParse, 1);
+      break;
     }
-    if( !isView ){
-      sqlite3VdbeAddOp2(v, OP_Clear, pTab->tnum, iDb);
-      if( !pParse->nested ){
-        sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
-      }
-      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-        assert( pIdx->pSchema==pTab->pSchema );
-        sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
-      }
+    case TK_OR: {
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
+      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+      break;
     }
-  } 
-  /* The usual case: There is a WHERE clause so we have to scan through
-  ** the table and pick which records to delete.
-  */
-  else{
-    int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
-
-    /* Begin the database scan
-    */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
-    if( pWInfo==0 ) goto delete_from_cleanup;
-
-    /* Remember the rowid of every item to be deleted.
-    */
-    sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, iRowid);
-    sqlite3VdbeAddOp1(v, OP_FifoWrite, iRowid);
-    if( db->flags & SQLITE_CountRows ){
-      sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
+    case TK_NOT: {
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+      break;
     }
-
-    /* End the database scan loop.
-    */
-    sqlite3WhereEnd(pWInfo);
-
-    /* Open the pseudo-table used to store OLD if there are triggers.
-    */
-    if( triggers_exist ){
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
-      sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
+    case TK_LT:
+    case TK_LE:
+    case TK_GT:
+    case TK_GE:
+    case TK_NE:
+    case TK_EQ: {
+      assert( TK_LT==OP_Lt );
+      assert( TK_LE==OP_Le );
+      assert( TK_GT==OP_Gt );
+      assert( TK_GE==OP_Ge );
+      assert( TK_EQ==OP_Eq );
+      assert( TK_NE==OP_Ne );
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      testcase( jumpIfNull==0 );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, dest, jumpIfNull);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
     }
-
-    /* Delete every item whose key was written to the list during the
-    ** database scan.  We have to delete items after the scan is complete
-    ** because deleting an item can change the scan order.
-    */
-    end = sqlite3VdbeMakeLabel(v);
-
-    if( !isView ){
-      /* Open cursors for the table we are deleting from and 
-      ** all its indices.
-      */
-      sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
+    case TK_IS:
+    case TK_ISNOT: {
+      testcase( op==TK_IS );
+      testcase( op==TK_ISNOT );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      op = (op==TK_IS) ? TK_EQ : TK_NE;
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, dest, SQLITE_NULLEQ);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
     }
-
-    /* This is the beginning of the delete loop. If a trigger encounters
-    ** an IGNORE constraint, it jumps back to here.
-    */
-    if( triggers_exist ){
-      sqlite3VdbeResolveLabel(v, addr);
+    case TK_ISNULL:
+    case TK_NOTNULL: {
+      assert( TK_ISNULL==OP_IsNull );
+      assert( TK_NOTNULL==OP_NotNull );
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+      sqlite3VdbeAddOp2(v, op, r1, dest);
+      testcase( regFree1==0 );
+      break;
     }
-    addr = sqlite3VdbeAddOp2(v, OP_FifoRead, iRowid, end);
-
-    if( triggers_exist ){
-      int iData = ++pParse->nMem;   /* For storing row data of OLD table */
-
-      /* If the record is no longer present in the table, jump to the
-      ** next iteration of the loop through the contents of the fifo.
+    case TK_BETWEEN: {
+      /*    x BETWEEN y AND z
+      **
+      ** Is equivalent to 
+      **
+      **    x>=y AND x<=z
+      **
+      ** Code it as such, taking care to do the common subexpression
+      ** elementation of x.
       */
-      sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
-
-      /* Populate the OLD.* pseudo-table */
-      if( old_col_mask ){
-        sqlite3VdbeAddOp2(v, OP_RowData, iCur, iData);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_Null, 0, iData);
-      }
-      sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);
-
-      /* Jump back and run the BEFORE triggers */
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
-      sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
-    }
+      Expr exprAnd;
+      Expr compLeft;
+      Expr compRight;
+      Expr exprX;
 
-    if( !isView ){
-      /* Delete the row */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      if( IsVirtual(pTab) ){
-        const char *pVtab = (const char *)pTab->pVtab;
-        sqlite3VtabMakeWritable(pParse, pTab);
-        sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
-      }else
-#endif
-      {
-        sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, pParse->nested==0);
-      }
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      exprX = *pExpr->pLeft;
+      exprAnd.op = TK_AND;
+      exprAnd.pLeft = &compLeft;
+      exprAnd.pRight = &compRight;
+      compLeft.op = TK_GE;
+      compLeft.pLeft = &exprX;
+      compLeft.pRight = pExpr->x.pList->a[0].pExpr;
+      compRight.op = TK_LE;
+      compRight.pLeft = &exprX;
+      compRight.pRight = pExpr->x.pList->a[1].pExpr;
+      exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
+      testcase( regFree1==0 );
+      exprX.op = TK_REGISTER;
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
+      break;
     }
-
-    /* If there are row triggers, close all cursors then invoke
-    ** the AFTER triggers
-    */
-    if( triggers_exist ){
-      /* Jump back and run the AFTER triggers */
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
-      sqlite3VdbeJumpHere(v, iEndAfterTrigger);
+    default: {
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
+      sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
+      testcase( regFree1==0 );
+      testcase( jumpIfNull==0 );
+      break;
     }
+  }
+  sqlite3ReleaseTempReg(pParse, regFree1);
+  sqlite3ReleaseTempReg(pParse, regFree2);  
+}
 
-    /* End of the delete loop */
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
-    sqlite3VdbeResolveLabel(v, end);
+/*
+** Generate code for a boolean expression such that a jump is made
+** to the label "dest" if the expression is false but execution
+** continues straight thru if the expression is true.
+**
+** If the expression evaluates to NULL (neither true nor false) then
+** jump if jumpIfNull is SQLITE_JUMPIFNULL or fall through if jumpIfNull
+** is 0.
+*/
+SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
+  Vdbe *v = pParse->pVdbe;
+  int op = 0;
+  int regFree1 = 0;
+  int regFree2 = 0;
+  int r1, r2;
 
-    /* Close the cursors after the loop if there are no row triggers */
-    if( !isView  && !IsVirtual(pTab) ){
-      for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
-        sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
-      }
-      sqlite3VdbeAddOp1(v, OP_Close, iCur);
+  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
+  if( NEVER(v==0) ) return; /* Existance of VDBE checked by caller */
+  if( pExpr==0 )    return;
+
+  /* The value of pExpr->op and op are related as follows:
+  **
+  **       pExpr->op            op
+  **       ---------          ----------
+  **       TK_ISNULL          OP_NotNull
+  **       TK_NOTNULL         OP_IsNull
+  **       TK_NE              OP_Eq
+  **       TK_EQ              OP_Ne
+  **       TK_GT              OP_Le
+  **       TK_LE              OP_Gt
+  **       TK_GE              OP_Lt
+  **       TK_LT              OP_Ge
+  **
+  ** For other values of pExpr->op, op is undefined and unused.
+  ** The value of TK_ and OP_ constants are arranged such that we
+  ** can compute the mapping above using the following expression.
+  ** Assert()s verify that the computation is correct.
+  */
+  op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);
+
+  /* Verify correct alignment of TK_ and OP_ constants
+  */
+  assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );
+  assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );
+  assert( pExpr->op!=TK_NE || op==OP_Eq );
+  assert( pExpr->op!=TK_EQ || op==OP_Ne );
+  assert( pExpr->op!=TK_LT || op==OP_Ge );
+  assert( pExpr->op!=TK_LE || op==OP_Gt );
+  assert( pExpr->op!=TK_GT || op==OP_Le );
+  assert( pExpr->op!=TK_GE || op==OP_Lt );
+
+  switch( pExpr->op ){
+    case TK_AND: {
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+      break;
+    }
+    case TK_OR: {
+      int d2 = sqlite3VdbeMakeLabel(v);
+      testcase( jumpIfNull==0 );
+      sqlite3ExprCachePush(pParse);
+      sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
+      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+      sqlite3VdbeResolveLabel(v, d2);
+      sqlite3ExprCachePop(pParse, 1);
+      break;
+    }
+    case TK_NOT: {
+      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
+      break;
+    }
+    case TK_LT:
+    case TK_LE:
+    case TK_GT:
+    case TK_GE:
+    case TK_NE:
+    case TK_EQ: {
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      testcase( jumpIfNull==0 );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, dest, jumpIfNull);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_IS:
+    case TK_ISNOT: {
+      testcase( pExpr->op==TK_IS );
+      testcase( pExpr->op==TK_ISNOT );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, &regFree1,
+                                  pExpr->pRight, &r2, &regFree2);
+      op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ;
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, dest, SQLITE_NULLEQ);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_ISNULL:
+    case TK_NOTNULL: {
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+      sqlite3VdbeAddOp2(v, op, r1, dest);
+      testcase( regFree1==0 );
+      break;
+    }
+    case TK_BETWEEN: {
+      /*    x BETWEEN y AND z
+      **
+      ** Is equivalent to 
+      **
+      **    x>=y AND x<=z
+      **
+      ** Code it as such, taking care to do the common subexpression
+      ** elementation of x.
+      */
+      Expr exprAnd;
+      Expr compLeft;
+      Expr compRight;
+      Expr exprX;
+
+      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      exprX = *pExpr->pLeft;
+      exprAnd.op = TK_AND;
+      exprAnd.pLeft = &compLeft;
+      exprAnd.pRight = &compRight;
+      compLeft.op = TK_GE;
+      compLeft.pLeft = &exprX;
+      compLeft.pRight = pExpr->x.pList->a[0].pExpr;
+      compRight.op = TK_LE;
+      compRight.pLeft = &exprX;
+      compRight.pRight = pExpr->x.pList->a[1].pExpr;
+      exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
+      testcase( regFree1==0 );
+      exprX.op = TK_REGISTER;
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
+      break;
+    }
+    default: {
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
+      sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
+      testcase( regFree1==0 );
+      testcase( jumpIfNull==0 );
+      break;
     }
   }
+  sqlite3ReleaseTempReg(pParse, regFree1);
+  sqlite3ReleaseTempReg(pParse, regFree2);
+}
 
-  /*
-  ** Return the number of rows that were deleted. If this routine is 
-  ** generating code because of a call to sqlite3NestedParse(), do not
-  ** invoke the callback function.
-  */
-  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
-    sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", P4_STATIC);
+/*
+** Do a deep comparison of two expression trees.  Return TRUE (non-zero)
+** if they are identical and return FALSE if they differ in any way.
+**
+** Sometimes this routine will return FALSE even if the two expressions
+** really are equivalent.  If we cannot prove that the expressions are
+** identical, we return FALSE just to be safe.  So if this routine
+** returns false, then you do not really know for certain if the two
+** expressions are the same.  But if you get a TRUE return, then you
+** can be sure the expressions are the same.  In the places where
+** this routine is used, it does not hurt to get an extra FALSE - that
+** just might result in some slightly slower code.  But returning
+** an incorrect TRUE could lead to a malfunction.
+*/
+SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
+  int i;
+  if( pA==0||pB==0 ){
+    return pB==pA;
+  }
+  assert( !ExprHasAnyProperty(pA, EP_TokenOnly|EP_Reduced) );
+  assert( !ExprHasAnyProperty(pB, EP_TokenOnly|EP_Reduced) );
+  if( ExprHasProperty(pA, EP_xIsSelect) || ExprHasProperty(pB, EP_xIsSelect) ){
+    return 0;
   }
+  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0;
+  if( pA->op!=pB->op ) return 0;
+  if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;
+  if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;
 
-delete_from_cleanup:
-  sqlite3AuthContextPop(&sContext);
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprDelete(pWhere);
-  return;
+  if( pA->x.pList && pB->x.pList ){
+    if( pA->x.pList->nExpr!=pB->x.pList->nExpr ) return 0;
+    for(i=0; i<pA->x.pList->nExpr; i++){
+      Expr *pExprA = pA->x.pList->a[i].pExpr;
+      Expr *pExprB = pB->x.pList->a[i].pExpr;
+      if( !sqlite3ExprCompare(pExprA, pExprB) ) return 0;
+    }
+  }else if( pA->x.pList || pB->x.pList ){
+    return 0;
+  }
+
+  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;
+  if( ExprHasProperty(pA, EP_IntValue) ){
+    if( !ExprHasProperty(pB, EP_IntValue) || pA->u.iValue!=pB->u.iValue ){
+      return 0;
+    }
+  }else if( pA->op!=TK_COLUMN && pA->u.zToken ){
+    if( ExprHasProperty(pB, EP_IntValue) || NEVER(pB->u.zToken==0) ) return 0;
+    if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ){
+      return 0;
+    }
+  }
+  return 1;
 }
 
+
 /*
-** This routine generates VDBE code that causes a single row of a
-** single table to be deleted.
-**
-** The VDBE must be in a particular state when this routine is called.
-** These are the requirements:
-**
-**   1.  A read/write cursor pointing to pTab, the table containing the row
-**       to be deleted, must be opened as cursor number "base".
-**
-**   2.  Read/write cursors for all indices of pTab must be open as
-**       cursor number base+i for the i-th index.
-**
-**   3.  The record number of the row to be deleted must be stored in
-**       memory cell iRowid.
-**
-** This routine pops the top of the stack to remove the record number
-** and then generates code to remove both the table record and all index
-** entries that point to that record.
+** Add a new element to the pAggInfo->aCol[] array.  Return the index of
+** the new element.  Return a negative number if malloc fails.
 */
-SQLITE_PRIVATE void sqlite3GenerateRowDelete(
-  Parse *pParse,     /* Parsing context */
-  Table *pTab,       /* Table containing the row to be deleted */
-  int iCur,          /* Cursor number for the table */
-  int iRowid,        /* Memory cell that contains the rowid to delete */
-  int count          /* Increment the row change counter */
-){
-  int addr;
-  Vdbe *v;
+static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){
+  int i;
+  pInfo->aCol = sqlite3ArrayAllocate(
+       db,
+       pInfo->aCol,
+       sizeof(pInfo->aCol[0]),
+       3,
+       &pInfo->nColumn,
+       &pInfo->nColumnAlloc,
+       &i
+  );
+  return i;
+}    
 
-  v = pParse->pVdbe;
-  addr = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowid);
-  sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
-  sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
-  if( count ){
-    sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
+/*
+** Add a new element to the pAggInfo->aFunc[] array.  Return the index of
+** the new element.  Return a negative number if malloc fails.
+*/
+static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){
+  int i;
+  pInfo->aFunc = sqlite3ArrayAllocate(
+       db, 
+       pInfo->aFunc,
+       sizeof(pInfo->aFunc[0]),
+       3,
+       &pInfo->nFunc,
+       &pInfo->nFuncAlloc,
+       &i
+  );
+  return i;
+}    
+
+/*
+** This is the xExprCallback for a tree walker.  It is used to
+** implement sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates
+** for additional information.
+*/
+static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
+  int i;
+  NameContext *pNC = pWalker->u.pNC;
+  Parse *pParse = pNC->pParse;
+  SrcList *pSrcList = pNC->pSrcList;
+  AggInfo *pAggInfo = pNC->pAggInfo;
+
+  switch( pExpr->op ){
+    case TK_AGG_COLUMN:
+    case TK_COLUMN: {
+      testcase( pExpr->op==TK_AGG_COLUMN );
+      testcase( pExpr->op==TK_COLUMN );
+      /* Check to see if the column is in one of the tables in the FROM
+      ** clause of the aggregate query */
+      if( ALWAYS(pSrcList!=0) ){
+        struct SrcList_item *pItem = pSrcList->a;
+        for(i=0; i<pSrcList->nSrc; i++, pItem++){
+          struct AggInfo_col *pCol;
+          assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
+          if( pExpr->iTable==pItem->iCursor ){
+            /* If we reach this point, it means that pExpr refers to a table
+            ** that is in the FROM clause of the aggregate query.  
+            **
+            ** Make an entry for the column in pAggInfo->aCol[] if there
+            ** is not an entry there already.
+            */
+            int k;
+            pCol = pAggInfo->aCol;
+            for(k=0; k<pAggInfo->nColumn; k++, pCol++){
+              if( pCol->iTable==pExpr->iTable &&
+                  pCol->iColumn==pExpr->iColumn ){
+                break;
+              }
+            }
+            if( (k>=pAggInfo->nColumn)
+             && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 
+            ){
+              pCol = &pAggInfo->aCol[k];
+              pCol->pTab = pExpr->pTab;
+              pCol->iTable = pExpr->iTable;
+              pCol->iColumn = pExpr->iColumn;
+              pCol->iMem = ++pParse->nMem;
+              pCol->iSorterColumn = -1;
+              pCol->pExpr = pExpr;
+              if( pAggInfo->pGroupBy ){
+                int j, n;
+                ExprList *pGB = pAggInfo->pGroupBy;
+                struct ExprList_item *pTerm = pGB->a;
+                n = pGB->nExpr;
+                for(j=0; j<n; j++, pTerm++){
+                  Expr *pE = pTerm->pExpr;
+                  if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable &&
+                      pE->iColumn==pExpr->iColumn ){
+                    pCol->iSorterColumn = j;
+                    break;
+                  }
+                }
+              }
+              if( pCol->iSorterColumn<0 ){
+                pCol->iSorterColumn = pAggInfo->nSortingColumn++;
+              }
+            }
+            /* There is now an entry for pExpr in pAggInfo->aCol[] (either
+            ** because it was there before or because we just created it).
+            ** Convert the pExpr to be a TK_AGG_COLUMN referring to that
+            ** pAggInfo->aCol[] entry.
+            */
+            ExprSetIrreducible(pExpr);
+            pExpr->pAggInfo = pAggInfo;
+            pExpr->op = TK_AGG_COLUMN;
+            pExpr->iAgg = (i16)k;
+            break;
+          } /* endif pExpr->iTable==pItem->iCursor */
+        } /* end loop over pSrcList */
+      }
+      return WRC_Prune;
+    }
+    case TK_AGG_FUNCTION: {
+      /* The pNC->nDepth==0 test causes aggregate functions in subqueries
+      ** to be ignored */
+      if( pNC->nDepth==0 ){
+        /* Check to see if pExpr is a duplicate of another aggregate 
+        ** function that is already in the pAggInfo structure
+        */
+        struct AggInfo_func *pItem = pAggInfo->aFunc;
+        for(i=0; i<pAggInfo->nFunc; i++, pItem++){
+          if( sqlite3ExprCompare(pItem->pExpr, pExpr) ){
+            break;
+          }
+        }
+        if( i>=pAggInfo->nFunc ){
+          /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]
+          */
+          u8 enc = ENC(pParse->db);
+          i = addAggInfoFunc(pParse->db, pAggInfo);
+          if( i>=0 ){
+            assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+            pItem = &pAggInfo->aFunc[i];
+            pItem->pExpr = pExpr;
+            pItem->iMem = ++pParse->nMem;
+            assert( !ExprHasProperty(pExpr, EP_IntValue) );
+            pItem->pFunc = sqlite3FindFunction(pParse->db,
+                   pExpr->u.zToken, sqlite3Strlen30(pExpr->u.zToken),
+                   pExpr->x.pList ? pExpr->x.pList->nExpr : 0, enc, 0);
+            if( pExpr->flags & EP_Distinct ){
+              pItem->iDistinct = pParse->nTab++;
+            }else{
+              pItem->iDistinct = -1;
+            }
+          }
+        }
+        /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
+        */
+        assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
+        ExprSetIrreducible(pExpr);
+        pExpr->iAgg = (i16)i;
+        pExpr->pAggInfo = pAggInfo;
+        return WRC_Prune;
+      }
+    }
+  }
+  return WRC_Continue;
+}
+static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
+  NameContext *pNC = pWalker->u.pNC;
+  if( pNC->nDepth==0 ){
+    pNC->nDepth++;
+    sqlite3WalkSelect(pWalker, pSelect);
+    pNC->nDepth--;
+    return WRC_Prune;
+  }else{
+    return WRC_Continue;
   }
-  sqlite3VdbeJumpHere(v, addr);
 }
 
 /*
-** This routine generates VDBE code that causes the deletion of all
-** index entries associated with a single row of a single table.
-**
-** The VDBE must be in a particular state when this routine is called.
-** These are the requirements:
-**
-**   1.  A read/write cursor pointing to pTab, the table containing the row
-**       to be deleted, must be opened as cursor number "iCur".
+** Analyze the given expression looking for aggregate functions and
+** for variables that need to be added to the pParse->aAgg[] array.
+** Make additional entries to the pParse->aAgg[] array as necessary.
 **
-**   2.  Read/write cursors for all indices of pTab must be open as
-**       cursor number iCur+i for the i-th index.
+** This routine should only be called after the expression has been
+** analyzed by sqlite3ResolveExprNames().
+*/
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
+  Walker w;
+  w.xExprCallback = analyzeAggregate;
+  w.xSelectCallback = analyzeAggregatesInSelect;
+  w.u.pNC = pNC;
+  assert( pNC->pSrcList!=0 );
+  sqlite3WalkExpr(&w, pExpr);
+}
+
+/*
+** Call sqlite3ExprAnalyzeAggregates() for every expression in an
+** expression list.  Return the number of errors.
 **
-**   3.  The "iCur" cursor must be pointing to the row that is to be
-**       deleted.
+** If an error is found, the analysis is cut short.
 */
-SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
-  Parse *pParse,     /* Parsing and code generating context */
-  Table *pTab,       /* Table containing the row to be deleted */
-  int iCur,          /* Cursor number for the table */
-  int *aRegIdx       /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
-){
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){
+  struct ExprList_item *pItem;
   int i;
-  Index *pIdx;
-  int r1;
+  if( pList ){
+    for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
+      sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr);
+    }
+  }
+}
 
-  for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
-    if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
-    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
-    sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
+/*
+** Allocate a single new register for use to hold some intermediate result.
+*/
+SQLITE_PRIVATE int sqlite3GetTempReg(Parse *pParse){
+  if( pParse->nTempReg==0 ){
+    return ++pParse->nMem;
   }
+  return pParse->aTempReg[--pParse->nTempReg];
 }
 
 /*
-** Generate code that will assemble an index key and put it in register
-** regOut.  The key with be for index pIdx which is an index on pTab.
-** iCur is the index of a cursor open on the pTab table and pointing to
-** the entry that needs indexing.
+** Deallocate a register, making available for reuse for some other
+** purpose.
 **
-** Return a register number which is the first in a block of
-** registers that holds the elements of the index key.  The
-** block of registers has already been deallocated by the time
-** this routine returns.
+** If a register is currently being used by the column cache, then
+** the dallocation is deferred until the column cache line that uses
+** the register becomes stale.
 */
-SQLITE_PRIVATE int sqlite3GenerateIndexKey(
-  Parse *pParse,     /* Parsing context */
-  Index *pIdx,       /* The index for which to generate a key */
-  int iCur,          /* Cursor number for the pIdx->pTable table */
-  int regOut,        /* Write the new index key to this register */
-  int doMakeRec      /* Run the OP_MakeRecord instruction if true */
-){
-  Vdbe *v = pParse->pVdbe;
-  int j;
-  Table *pTab = pIdx->pTable;
-  int regBase;
-  int nCol;
-
-  nCol = pIdx->nColumn;
-  regBase = sqlite3GetTempRange(pParse, nCol+1);
-  sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
-  for(j=0; j<nCol; j++){
-    int idx = pIdx->aiColumn[j];
-    if( idx==pTab->iPKey ){
-      sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
-    }else{
-      sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
-      sqlite3ColumnDefault(v, pTab, idx);
+SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
+  if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){
+    int i;
+    struct yColCache *p;
+    for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
+      if( p->iReg==iReg ){
+        p->tempReg = 1;
+        return;
+      }
     }
+    pParse->aTempReg[pParse->nTempReg++] = iReg;
   }
-  if( doMakeRec ){
-    sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
-    sqlite3IndexAffinityStr(v, pIdx);
-    sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
-  }
-  sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
-  return regBase;
 }
 
-/* Make sure "isView" gets undefined in case this file becomes part of
-** the amalgamation - so that subsequent files do not see isView as a
-** macro. */
-#undef isView
+/*
+** Allocate or deallocate a block of nReg consecutive registers
+*/
+SQLITE_PRIVATE int sqlite3GetTempRange(Parse *pParse, int nReg){
+  int i, n;
+  i = pParse->iRangeReg;
+  n = pParse->nRangeReg;
+  if( nReg<=n && !usedAsColumnCache(pParse, i, i+n-1) ){
+    pParse->iRangeReg += nReg;
+    pParse->nRangeReg -= nReg;
+  }else{
+    i = pParse->nMem+1;
+    pParse->nMem += nReg;
+  }
+  return i;
+}
+SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
+  if( nReg>pParse->nRangeReg ){
+    pParse->nRangeReg = nReg;
+    pParse->iRangeReg = iReg;
+  }
+}
 
-/************** End of delete.c **********************************************/
-/************** Begin file func.c ********************************************/
+/************** End of expr.c ************************************************/
+/************** Begin file alter.c *******************************************/
 /*
-** 2002 February 23
+** 2005 February 15
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -57268,18903 +63545,33566 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains the C functions that implement various SQL
-** functions of SQLite.  
-**
-** There is only one exported symbol in this file - the function
-** sqliteRegisterBuildinFunctions() found at the bottom of the file.
-** All other code has file scope.
+** This file contains C code routines that used to generate VDBE code
+** that implements the ALTER TABLE command.
 **
-** $Id: func.c,v 1.192 2008/04/27 18:40:12 drh Exp $
+** $Id: alter.c,v 1.62 2009/07/24 17:58:53 danielk1977 Exp $
 */
 
-
 /*
-** Return the collating function associated with a function.
+** The code in this file only exists if we are not omitting the
+** ALTER TABLE logic from the build.
 */
-static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
-  return context->pColl;
-}
+#ifndef SQLITE_OMIT_ALTERTABLE
+
 
 /*
-** Implementation of the non-aggregate min() and max() functions
+** This function is used by SQL generated to implement the 
+** ALTER TABLE command. The first argument is the text of a CREATE TABLE or
+** CREATE INDEX command. The second is a table name. The table name in 
+** the CREATE TABLE or CREATE INDEX statement is replaced with the third
+** argument and the result returned. Examples:
+**
+** sqlite_rename_table('CREATE TABLE abc(a, b, c)', 'def')
+**     -> 'CREATE TABLE def(a, b, c)'
+**
+** sqlite_rename_table('CREATE INDEX i ON abc(a)', 'def')
+**     -> 'CREATE INDEX i ON def(a, b, c)'
 */
-static void minmaxFunc(
+static void renameTableFunc(
   sqlite3_context *context,
-  int argc,
+  int NotUsed,
   sqlite3_value **argv
 ){
-  int i;
-  int mask;    /* 0 for min() or 0xffffffff for max() */
-  int iBest;
-  CollSeq *pColl;
+  unsigned char const *zSql = sqlite3_value_text(argv[0]);
+  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
 
-  if( argc==0 ) return;
-  mask = sqlite3_user_data(context)==0 ? 0 : -1;
-  pColl = sqlite3GetFuncCollSeq(context);
-  assert( pColl );
-  assert( mask==-1 || mask==0 );
-  iBest = 0;
-  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
-  for(i=1; i<argc; i++){
-    if( sqlite3_value_type(argv[i])==SQLITE_NULL ) return;
-    if( (sqlite3MemCompare(argv[iBest], argv[i], pColl)^mask)>=0 ){
-      iBest = i;
-    }
+  int token;
+  Token tname;
+  unsigned char const *zCsr = zSql;
+  int len = 0;
+  char *zRet;
+
+  sqlite3 *db = sqlite3_context_db_handle(context);
+
+  UNUSED_PARAMETER(NotUsed);
+
+  /* The principle used to locate the table name in the CREATE TABLE 
+  ** statement is that the table name is the first non-space token that
+  ** is immediately followed by a TK_LP or TK_USING token.
+  */
+  if( zSql ){
+    do {
+      if( !*zCsr ){
+        /* Ran out of input before finding an opening bracket. Return NULL. */
+        return;
+      }
+
+      /* Store the token that zCsr points to in tname. */
+      tname.z = (char*)zCsr;
+      tname.n = len;
+
+      /* Advance zCsr to the next token. Store that token type in 'token',
+      ** and its length in 'len' (to be used next iteration of this loop).
+      */
+      do {
+        zCsr += len;
+        len = sqlite3GetToken(zCsr, &token);
+      } while( token==TK_SPACE );
+      assert( len>0 );
+    } while( token!=TK_LP && token!=TK_USING );
+
+    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", ((u8*)tname.z) - zSql, zSql, 
+       zTableName, tname.z+tname.n);
+    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
   }
-  sqlite3_result_value(context, argv[iBest]);
 }
 
 /*
-** Return the type of the argument.
+** This C function implements an SQL user function that is used by SQL code
+** generated by the ALTER TABLE ... RENAME command to modify the definition
+** of any foreign key constraints that use the table being renamed as the 
+** parent table. It is passed three arguments:
+**
+**   1) The complete text of the CREATE TABLE statement being modified,
+**   2) The old name of the table being renamed, and
+**   3) The new name of the table being renamed.
+**
+** It returns the new CREATE TABLE statement. For example:
+**
+**   sqlite_rename_parent('CREATE TABLE t1(a REFERENCES t2)', 't2', 't3')
+**       -> 'CREATE TABLE t1(a REFERENCES t3)'
 */
-static void typeofFunc(
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+static void renameParentFunc(
   sqlite3_context *context,
-  int argc,
+  int NotUsed,
   sqlite3_value **argv
 ){
-  const char *z = 0;
-  switch( sqlite3_value_type(argv[0]) ){
-    case SQLITE_NULL:    z = "null";    break;
-    case SQLITE_INTEGER: z = "integer"; break;
-    case SQLITE_TEXT:    z = "text";    break;
-    case SQLITE_FLOAT:   z = "real";    break;
-    case SQLITE_BLOB:    z = "blob";    break;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  char *zOutput = 0;
+  char *zResult;
+  unsigned char const *zInput = sqlite3_value_text(argv[0]);
+  unsigned char const *zOld = sqlite3_value_text(argv[1]);
+  unsigned char const *zNew = sqlite3_value_text(argv[2]);
+
+  unsigned const char *z;         /* Pointer to token */
+  int n;                          /* Length of token z */
+  int token;                      /* Type of token */
+
+  UNUSED_PARAMETER(NotUsed);
+  for(z=zInput; *z; z=z+n){
+    n = sqlite3GetToken(z, &token);
+    if( token==TK_REFERENCES ){
+      char *zParent;
+      do {
+        z += n;
+        n = sqlite3GetToken(z, &token);
+      }while( token==TK_SPACE );
+
+      zParent = sqlite3DbStrNDup(db, (const char *)z, n);
+      if( zParent==0 ) break;
+      sqlite3Dequote(zParent);
+      if( 0==sqlite3StrICmp((const char *)zOld, zParent) ){
+        char *zOut = sqlite3MPrintf(db, "%s%.*s\"%w\"", 
+            (zOutput?zOutput:""), z-zInput, zInput, (const char *)zNew
+        );
+        sqlite3DbFree(db, zOutput);
+        zOutput = zOut;
+        zInput = &z[n];
+      }
+      sqlite3DbFree(db, zParent);
+    }
   }
-  sqlite3_result_text(context, z, -1, SQLITE_STATIC);
-}
 
+  zResult = sqlite3MPrintf(db, "%s%s", (zOutput?zOutput:""), zInput), 
+  sqlite3_result_text(context, zResult, -1, SQLITE_DYNAMIC);
+  sqlite3DbFree(db, zOutput);
+}
+#endif
 
-/*
-** Implementation of the length() function
+#ifndef SQLITE_OMIT_TRIGGER
+/* This function is used by SQL generated to implement the
+** ALTER TABLE command. The first argument is the text of a CREATE TRIGGER 
+** statement. The second is a table name. The table name in the CREATE 
+** TRIGGER statement is replaced with the third argument and the result 
+** returned. This is analagous to renameTableFunc() above, except for CREATE
+** TRIGGER, not CREATE INDEX and CREATE TABLE.
 */
-static void lengthFunc(
+static void renameTriggerFunc(
   sqlite3_context *context,
-  int argc,
+  int NotUsed,
   sqlite3_value **argv
 ){
-  int len;
+  unsigned char const *zSql = sqlite3_value_text(argv[0]);
+  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
 
-  assert( argc==1 );
-  switch( sqlite3_value_type(argv[0]) ){
-    case SQLITE_BLOB:
-    case SQLITE_INTEGER:
-    case SQLITE_FLOAT: {
-      sqlite3_result_int(context, sqlite3_value_bytes(argv[0]));
-      break;
-    }
-    case SQLITE_TEXT: {
-      const unsigned char *z = sqlite3_value_text(argv[0]);
-      if( z==0 ) return;
-      len = 0;
-      while( *z ){
-        len++;
-        SQLITE_SKIP_UTF8(z);
+  int token;
+  Token tname;
+  int dist = 3;
+  unsigned char const *zCsr = zSql;
+  int len = 0;
+  char *zRet;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+
+  UNUSED_PARAMETER(NotUsed);
+
+  /* The principle used to locate the table name in the CREATE TRIGGER 
+  ** statement is that the table name is the first token that is immediatedly
+  ** preceded by either TK_ON or TK_DOT and immediatedly followed by one
+  ** of TK_WHEN, TK_BEGIN or TK_FOR.
+  */
+  if( zSql ){
+    do {
+
+      if( !*zCsr ){
+        /* Ran out of input before finding the table name. Return NULL. */
+        return;
       }
-      sqlite3_result_int(context, len);
-      break;
-    }
-    default: {
-      sqlite3_result_null(context);
-      break;
-    }
+
+      /* Store the token that zCsr points to in tname. */
+      tname.z = (char*)zCsr;
+      tname.n = len;
+
+      /* Advance zCsr to the next token. Store that token type in 'token',
+      ** and its length in 'len' (to be used next iteration of this loop).
+      */
+      do {
+        zCsr += len;
+        len = sqlite3GetToken(zCsr, &token);
+      }while( token==TK_SPACE );
+      assert( len>0 );
+
+      /* Variable 'dist' stores the number of tokens read since the most
+      ** recent TK_DOT or TK_ON. This means that when a WHEN, FOR or BEGIN 
+      ** token is read and 'dist' equals 2, the condition stated above
+      ** to be met.
+      **
+      ** Note that ON cannot be a database, table or column name, so
+      ** there is no need to worry about syntax like 
+      ** "CREATE TRIGGER ... ON ON.ON BEGIN ..." etc.
+      */
+      dist++;
+      if( token==TK_DOT || token==TK_ON ){
+        dist = 0;
+      }
+    } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );
+
+    /* Variable tname now contains the token that is the old table-name
+    ** in the CREATE TRIGGER statement.
+    */
+    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", ((u8*)tname.z) - zSql, zSql, 
+       zTableName, tname.z+tname.n);
+    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
   }
 }
+#endif   /* !SQLITE_OMIT_TRIGGER */
 
 /*
-** Implementation of the abs() function
+** Register built-in functions used to help implement ALTER TABLE
 */
-static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
-  assert( argc==1 );
-  switch( sqlite3_value_type(argv[0]) ){
-    case SQLITE_INTEGER: {
-      i64 iVal = sqlite3_value_int64(argv[0]);
-      if( iVal<0 ){
-        if( (iVal<<1)==0 ){
-          sqlite3_result_error(context, "integer overflow", -1);
-          return;
-        }
-        iVal = -iVal;
-      } 
-      sqlite3_result_int64(context, iVal);
-      break;
-    }
-    case SQLITE_NULL: {
-      sqlite3_result_null(context);
-      break;
-    }
-    default: {
-      double rVal = sqlite3_value_double(argv[0]);
-      if( rVal<0 ) rVal = -rVal;
-      sqlite3_result_double(context, rVal);
-      break;
-    }
-  }
+SQLITE_PRIVATE void sqlite3AlterFunctions(sqlite3 *db){
+  sqlite3CreateFunc(db, "sqlite_rename_table", 2, SQLITE_UTF8, 0,
+                         renameTableFunc, 0, 0);
+#ifndef SQLITE_OMIT_TRIGGER
+  sqlite3CreateFunc(db, "sqlite_rename_trigger", 2, SQLITE_UTF8, 0,
+                         renameTriggerFunc, 0, 0);
+#endif
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+  sqlite3CreateFunc(db, "sqlite_rename_parent", 3, SQLITE_UTF8, 0,
+                         renameParentFunc, 0, 0);
+#endif
 }
 
 /*
-** Implementation of the substr() function.
+** This function is used to create the text of expressions of the form:
 **
-** substr(x,p1,p2)  returns p2 characters of x[] beginning with p1.
-** p1 is 1-indexed.  So substr(x,1,1) returns the first character
-** of x.  If x is text, then we actually count UTF-8 characters.
-** If x is a blob, then we count bytes.
+**   name=<constant1> OR name=<constant2> OR ...
 **
-** If p1 is negative, then we begin abs(p1) from the end of x[].
+** If argument zWhere is NULL, then a pointer string containing the text 
+** "name=<constant>" is returned, where <constant> is the quoted version
+** of the string passed as argument zConstant. The returned buffer is
+** allocated using sqlite3DbMalloc(). It is the responsibility of the
+** caller to ensure that it is eventually freed.
+**
+** If argument zWhere is not NULL, then the string returned is 
+** "<where> OR name=<constant>", where <where> is the contents of zWhere.
+** In this case zWhere is passed to sqlite3DbFree() before returning.
+** 
 */
-static void substrFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  const unsigned char *z;
-  const unsigned char *z2;
-  int len;
-  int p0type;
-  i64 p1, p2;
-
-  assert( argc==3 || argc==2 );
-  p0type = sqlite3_value_type(argv[0]);
-  if( p0type==SQLITE_BLOB ){
-    len = sqlite3_value_bytes(argv[0]);
-    z = sqlite3_value_blob(argv[0]);
-    if( z==0 ) return;
-    assert( len==sqlite3_value_bytes(argv[0]) );
-  }else{
-    z = sqlite3_value_text(argv[0]);
-    if( z==0 ) return;
-    len = 0;
-    for(z2=z; *z2; len++){
-      SQLITE_SKIP_UTF8(z2);
-    }
-  }
-  p1 = sqlite3_value_int(argv[1]);
-  if( argc==3 ){
-    p2 = sqlite3_value_int(argv[2]);
-  }else{
-    p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH];
-  }
-  if( p1<0 ){
-    p1 += len;
-    if( p1<0 ){
-      p2 += p1;
-      p1 = 0;
-    }
-  }else if( p1>0 ){
-    p1--;
-  }
-  if( p1+p2>len ){
-    p2 = len-p1;
-  }
-  if( p0type!=SQLITE_BLOB ){
-    while( *z && p1 ){
-      SQLITE_SKIP_UTF8(z);
-      p1--;
-    }
-    for(z2=z; *z2 && p2; p2--){
-      SQLITE_SKIP_UTF8(z2);
-    }
-    sqlite3_result_text(context, (char*)z, z2-z, SQLITE_TRANSIENT);
+static char *whereOrName(sqlite3 *db, char *zWhere, char *zConstant){
+  char *zNew;
+  if( !zWhere ){
+    zNew = sqlite3MPrintf(db, "name=%Q", zConstant);
   }else{
-    if( p2<0 ) p2 = 0;
-    sqlite3_result_blob(context, (char*)&z[p1], p2, SQLITE_TRANSIENT);
+    zNew = sqlite3MPrintf(db, "%s OR name=%Q", zWhere, zConstant);
+    sqlite3DbFree(db, zWhere);
   }
+  return zNew;
 }
 
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
 /*
-** Implementation of the round() function
+** Generate the text of a WHERE expression which can be used to select all
+** tables that have foreign key constraints that refer to table pTab (i.e.
+** constraints for which pTab is the parent table) from the sqlite_master
+** table.
 */
-static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
-  int n = 0;
-  double r;
-  char zBuf[500];  /* larger than the %f representation of the largest double */
-  assert( argc==1 || argc==2 );
-  if( argc==2 ){
-    if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return;
-    n = sqlite3_value_int(argv[1]);
-    if( n>30 ) n = 30;
-    if( n<0 ) n = 0;
+static char *whereForeignKeys(Parse *pParse, Table *pTab){
+  FKey *p;
+  char *zWhere = 0;
+  for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
+    zWhere = whereOrName(pParse->db, zWhere, p->pFrom->zName);
   }
-  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
-  r = sqlite3_value_double(argv[0]);
-  sqlite3_snprintf(sizeof(zBuf),zBuf,"%.*f",n,r);
-  sqlite3AtoF(zBuf, &r);
-  sqlite3_result_double(context, r);
+  return zWhere;
 }
+#endif
 
 /*
-** Allocate nByte bytes of space using sqlite3_malloc(). If the
-** allocation fails, call sqlite3_result_error_nomem() to notify
-** the database handle that malloc() has failed.
+** Generate the text of a WHERE expression which can be used to select all
+** temporary triggers on table pTab from the sqlite_temp_master table. If
+** table pTab has no temporary triggers, or is itself stored in the 
+** temporary database, NULL is returned.
 */
-static void *contextMalloc(sqlite3_context *context, i64 nByte){
-  char *z;
-  if( nByte>sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH] ){
-    sqlite3_result_error_toobig(context);
-    z = 0;
-  }else{
-    z = sqlite3_malloc(nByte);
-    if( !z && nByte>0 ){
-      sqlite3_result_error_nomem(context);
-    }
-  }
-  return z;
-}
+static char *whereTempTriggers(Parse *pParse, Table *pTab){
+  Trigger *pTrig;
+  char *zWhere = 0;
+  const Schema *pTempSchema = pParse->db->aDb[1].pSchema; /* Temp db schema */
 
-/*
-** Implementation of the upper() and lower() SQL functions.
-*/
-static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
-  char *z1;
-  const char *z2;
-  int i, n;
-  if( argc<1 || SQLITE_NULL==sqlite3_value_type(argv[0]) ) return;
-  z2 = (char*)sqlite3_value_text(argv[0]);
-  n = sqlite3_value_bytes(argv[0]);
-  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
-  assert( z2==(char*)sqlite3_value_text(argv[0]) );
-  if( z2 ){
-    z1 = contextMalloc(context, ((i64)n)+1);
-    if( z1 ){
-      memcpy(z1, z2, n+1);
-      for(i=0; z1[i]; i++){
-        z1[i] = toupper(z1[i]);
-      }
-      sqlite3_result_text(context, z1, -1, sqlite3_free);
-    }
-  }
-}
-static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
-  char *z1;
-  const char *z2;
-  int i, n;
-  if( argc<1 || SQLITE_NULL==sqlite3_value_type(argv[0]) ) return;
-  z2 = (char*)sqlite3_value_text(argv[0]);
-  n = sqlite3_value_bytes(argv[0]);
-  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
-  assert( z2==(char*)sqlite3_value_text(argv[0]) );
-  if( z2 ){
-    z1 = contextMalloc(context, ((i64)n)+1);
-    if( z1 ){
-      memcpy(z1, z2, n+1);
-      for(i=0; z1[i]; i++){
-        z1[i] = tolower(z1[i]);
+  /* If the table is not located in the temp-db (in which case NULL is 
+  ** returned, loop through the tables list of triggers. For each trigger
+  ** that is not part of the temp-db schema, add a clause to the WHERE 
+  ** expression being built up in zWhere.
+  */
+  if( pTab->pSchema!=pTempSchema ){
+    sqlite3 *db = pParse->db;
+    for(pTrig=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){
+      if( pTrig->pSchema==pTempSchema ){
+        zWhere = whereOrName(db, zWhere, pTrig->zName);
       }
-      sqlite3_result_text(context, z1, -1, sqlite3_free);
     }
   }
+  return zWhere;
 }
 
 /*
-** Implementation of the IFNULL(), NVL(), and COALESCE() functions.  
-** All three do the same thing.  They return the first non-NULL
-** argument.
+** Generate code to drop and reload the internal representation of table
+** pTab from the database, including triggers and temporary triggers.
+** Argument zName is the name of the table in the database schema at
+** the time the generated code is executed. This can be different from
+** pTab->zName if this function is being called to code part of an 
+** "ALTER TABLE RENAME TO" statement.
 */
-static void ifnullFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  int i;
-  for(i=0; i<argc; i++){
-    if( SQLITE_NULL!=sqlite3_value_type(argv[i]) ){
-      sqlite3_result_value(context, argv[i]);
-      break;
-    }
-  }
-}
+static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
+  Vdbe *v;
+  char *zWhere;
+  int iDb;                   /* Index of database containing pTab */
+#ifndef SQLITE_OMIT_TRIGGER
+  Trigger *pTrig;
+#endif
 
-/*
-** Implementation of random().  Return a random integer.  
-*/
-static void randomFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  sqlite_int64 r;
-  sqlite3_randomness(sizeof(r), &r);
-  if( (r<<1)==0 ) r = 0;  /* Prevent 0x8000.... as the result so that we */
-                          /* can always do abs() of the result */
-  sqlite3_result_int64(context, r);
-}
+  v = sqlite3GetVdbe(pParse);
+  if( NEVER(v==0) ) return;
+  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
+  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+  assert( iDb>=0 );
 
-/*
-** Implementation of randomblob(N).  Return a random blob
-** that is N bytes long.
-*/
-static void randomBlob(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  int n;
-  unsigned char *p;
-  assert( argc==1 );
-  n = sqlite3_value_int(argv[0]);
-  if( n<1 ){
-    n = 1;
-  }
-  p = contextMalloc(context, n);
-  if( p ){
-    sqlite3_randomness(n, p);
-    sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
+#ifndef SQLITE_OMIT_TRIGGER
+  /* Drop any table triggers from the internal schema. */
+  for(pTrig=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){
+    int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
+    assert( iTrigDb==iDb || iTrigDb==1 );
+    sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->zName, 0);
   }
-}
+#endif
 
-/*
-** Implementation of the last_insert_rowid() SQL function.  The return
-** value is the same as the sqlite3_last_insert_rowid() API function.
-*/
-static void last_insert_rowid(
-  sqlite3_context *context, 
-  int arg, 
-  sqlite3_value **argv
-){
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  sqlite3_result_int64(context, sqlite3_last_insert_rowid(db));
-}
+  /* Drop the table and index from the internal schema.  */
+  sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
 
-/*
-** Implementation of the changes() SQL function.  The return value is the
-** same as the sqlite3_changes() API function.
-*/
-static void changes(
-  sqlite3_context *context,
-  int arg,
-  sqlite3_value **argv
-){
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  sqlite3_result_int(context, sqlite3_changes(db));
-}
+  /* Reload the table, index and permanent trigger schemas. */
+  zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
+  if( !zWhere ) return;
+  sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);
 
-/*
-** Implementation of the total_changes() SQL function.  The return value is
-** the same as the sqlite3_total_changes() API function.
-*/
-static void total_changes(
-  sqlite3_context *context,
-  int arg,
-  sqlite3_value **argv
-){
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  sqlite3_result_int(context, sqlite3_total_changes(db));
+#ifndef SQLITE_OMIT_TRIGGER
+  /* Now, if the table is not stored in the temp database, reload any temp 
+  ** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined. 
+  */
+  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
+    sqlite3VdbeAddOp4(v, OP_ParseSchema, 1, 0, 0, zWhere, P4_DYNAMIC);
+  }
+#endif
 }
 
 /*
-** A structure defining how to do GLOB-style comparisons.
-*/
-struct compareInfo {
-  u8 matchAll;
-  u8 matchOne;
-  u8 matchSet;
-  u8 noCase;
-};
-
-/*
-** For LIKE and GLOB matching on EBCDIC machines, assume that every
-** character is exactly one byte in size.  Also, all characters are
-** able to participate in upper-case-to-lower-case mappings in EBCDIC
-** whereas only characters less than 0x80 do in ASCII.
+** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
+** command. 
 */
-#if defined(SQLITE_EBCDIC)
-# define sqlite3Utf8Read(A,B,C)  (*(A++))
-# define GlogUpperToLower(A)     A = sqlite3UpperToLower[A]
-#else
-# define GlogUpperToLower(A)     if( A<0x80 ){ A = sqlite3UpperToLower[A]; }
+SQLITE_PRIVATE void sqlite3AlterRenameTable(
+  Parse *pParse,            /* Parser context. */
+  SrcList *pSrc,            /* The table to rename. */
+  Token *pName              /* The new table name. */
+){
+  int iDb;                  /* Database that contains the table */
+  char *zDb;                /* Name of database iDb */
+  Table *pTab;              /* Table being renamed */
+  char *zName = 0;          /* NULL-terminated version of pName */ 
+  sqlite3 *db = pParse->db; /* Database connection */
+  int nTabName;             /* Number of UTF-8 characters in zTabName */
+  const char *zTabName;     /* Original name of the table */
+  Vdbe *v;
+#ifndef SQLITE_OMIT_TRIGGER
+  char *zWhere = 0;         /* Where clause to locate temp triggers */
 #endif
+  VTable *pVTab = 0;        /* Non-zero if this is a v-tab with an xRename() */
+  
+  if( NEVER(db->mallocFailed) ) goto exit_rename_table;
+  assert( pSrc->nSrc==1 );
+  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
 
-static const struct compareInfo globInfo = { '*', '?', '[', 0 };
-/* The correct SQL-92 behavior is for the LIKE operator to ignore
-** case.  Thus  'a' LIKE 'A' would be true. */
-static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
-/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
-** is case sensitive causing 'a' LIKE 'A' to be false */
-static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };
+  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  if( !pTab ) goto exit_rename_table;
+  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+  zDb = db->aDb[iDb].zName;
 
-/*
-** Compare two UTF-8 strings for equality where the first string can
-** potentially be a "glob" expression.  Return true (1) if they
-** are the same and false (0) if they are different.
-**
-** Globbing rules:
-**
-**      '*'       Matches any sequence of zero or more characters.
-**
-**      '?'       Matches exactly one character.
-**
-**     [...]      Matches one character from the enclosed list of
-**                characters.
-**
-**     [^...]     Matches one character not in the enclosed list.
-**
-** With the [...] and [^...] matching, a ']' character can be included
-** in the list by making it the first character after '[' or '^'.  A
-** range of characters can be specified using '-'.  Example:
-** "[a-z]" matches any single lower-case letter.  To match a '-', make
-** it the last character in the list.
-**
-** This routine is usually quick, but can be N**2 in the worst case.
-**
-** Hints: to match '*' or '?', put them in "[]".  Like this:
-**
-**         abc[*]xyz        Matches "abc*xyz" only
-*/
-static int patternCompare(
-  const u8 *zPattern,              /* The glob pattern */
-  const u8 *zString,               /* The string to compare against the glob */
-  const struct compareInfo *pInfo, /* Information about how to do the compare */
-  const int esc                    /* The escape character */
-){
-  int c, c2;
-  int invert;
-  int seen;
-  u8 matchOne = pInfo->matchOne;
-  u8 matchAll = pInfo->matchAll;
-  u8 matchSet = pInfo->matchSet;
-  u8 noCase = pInfo->noCase; 
-  int prevEscape = 0;     /* True if the previous character was 'escape' */
+  /* Get a NULL terminated version of the new table name. */
+  zName = sqlite3NameFromToken(db, pName);
+  if( !zName ) goto exit_rename_table;
 
-  while( (c = sqlite3Utf8Read(zPattern,0,&zPattern))!=0 ){
-    if( !prevEscape && c==matchAll ){
-      while( (c=sqlite3Utf8Read(zPattern,0,&zPattern)) == matchAll
-               || c == matchOne ){
-        if( c==matchOne && sqlite3Utf8Read(zString, 0, &zString)==0 ){
-          return 0;
-        }
-      }
-      if( c==0 ){
-        return 1;
-      }else if( c==esc ){
-        c = sqlite3Utf8Read(zPattern, 0, &zPattern);
-        if( c==0 ){
-          return 0;
-        }
-      }else if( c==matchSet ){
-        assert( esc==0 );         /* This is GLOB, not LIKE */
-        assert( matchSet<0x80 );  /* '[' is a single-byte character */
-        while( *zString && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
-          SQLITE_SKIP_UTF8(zString);
-        }
-        return *zString!=0;
-      }
-      while( (c2 = sqlite3Utf8Read(zString,0,&zString))!=0 ){
-        if( noCase ){
-          GlogUpperToLower(c2);
-          GlogUpperToLower(c);
-          while( c2 != 0 && c2 != c ){
-            c2 = sqlite3Utf8Read(zString, 0, &zString);
-            GlogUpperToLower(c2);
-          }
-        }else{
-          while( c2 != 0 && c2 != c ){
-            c2 = sqlite3Utf8Read(zString, 0, &zString);
-          }
-        }
-        if( c2==0 ) return 0;
-        if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
-      }
-      return 0;
-    }else if( !prevEscape && c==matchOne ){
-      if( sqlite3Utf8Read(zString, 0, &zString)==0 ){
-        return 0;
-      }
-    }else if( c==matchSet ){
-      int prior_c = 0;
-      assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
-      seen = 0;
-      invert = 0;
-      c = sqlite3Utf8Read(zString, 0, &zString);
-      if( c==0 ) return 0;
-      c2 = sqlite3Utf8Read(zPattern, 0, &zPattern);
-      if( c2=='^' ){
-        invert = 1;
-        c2 = sqlite3Utf8Read(zPattern, 0, &zPattern);
-      }
-      if( c2==']' ){
-        if( c==']' ) seen = 1;
-        c2 = sqlite3Utf8Read(zPattern, 0, &zPattern);
-      }
-      while( c2 && c2!=']' ){
-        if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
-          c2 = sqlite3Utf8Read(zPattern, 0, &zPattern);
-          if( c>=prior_c && c<=c2 ) seen = 1;
-          prior_c = 0;
-        }else{
-          if( c==c2 ){
-            seen = 1;
-          }
-          prior_c = c2;
-        }
-        c2 = sqlite3Utf8Read(zPattern, 0, &zPattern);
-      }
-      if( c2==0 || (seen ^ invert)==0 ){
-        return 0;
-      }
-    }else if( esc==c && !prevEscape ){
-      prevEscape = 1;
-    }else{
-      c2 = sqlite3Utf8Read(zString, 0, &zString);
-      if( noCase ){
-        GlogUpperToLower(c);
-        GlogUpperToLower(c2);
-      }
-      if( c!=c2 ){
-        return 0;
-      }
-      prevEscape = 0;
-    }
+  /* Check that a table or index named 'zName' does not already exist
+  ** in database iDb. If so, this is an error.
+  */
+  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
+    sqlite3ErrorMsg(pParse, 
+        "there is already another table or index with this name: %s", zName);
+    goto exit_rename_table;
   }
-  return *zString==0;
-}
 
-/*
-** Count the number of times that the LIKE operator (or GLOB which is
-** just a variation of LIKE) gets called.  This is used for testing
-** only.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_like_count = 0;
-#endif
+  /* Make sure it is not a system table being altered, or a reserved name
+  ** that the table is being renamed to.
+  */
+  if( sqlite3Strlen30(pTab->zName)>6 
+   && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7)
+  ){
+    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
+    goto exit_rename_table;
+  }
+  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
+    goto exit_rename_table;
+  }
 
+#ifndef SQLITE_OMIT_VIEW
+  if( pTab->pSelect ){
+    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
+    goto exit_rename_table;
+  }
+#endif
 
-/*
-** Implementation of the like() SQL function.  This function implements
-** the build-in LIKE operator.  The first argument to the function is the
-** pattern and the second argument is the string.  So, the SQL statements:
-**
-**       A LIKE B
-**
-** is implemented as like(B,A).
-**
-** This same function (with a different compareInfo structure) computes
-** the GLOB operator.
-*/
-static void likeFunc(
-  sqlite3_context *context, 
-  int argc, 
-  sqlite3_value **argv
-){
-  const unsigned char *zA, *zB;
-  int escape = 0;
-  sqlite3 *db = sqlite3_context_db_handle(context);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  /* Invoke the authorization callback. */
+  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
+    goto exit_rename_table;
+  }
+#endif
 
-  zB = sqlite3_value_text(argv[0]);
-  zA = sqlite3_value_text(argv[1]);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
+    goto exit_rename_table;
+  }
+  if( IsVirtual(pTab) ){
+    pVTab = sqlite3GetVTable(db, pTab);
+    if( pVTab->pVtab->pModule->xRename==0 ){
+      pVTab = 0;
+    }
+  }
+#endif
 
-  /* Limit the length of the LIKE or GLOB pattern to avoid problems
-  ** of deep recursion and N*N behavior in patternCompare().
+  /* Begin a transaction and code the VerifyCookie for database iDb. 
+  ** Then modify the schema cookie (since the ALTER TABLE modifies the
+  ** schema). Open a statement transaction if the table is a virtual
+  ** table.
   */
-  if( sqlite3_value_bytes(argv[0]) >
-        db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){
-    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
-    return;
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ){
+    goto exit_rename_table;
   }
-  assert( zB==sqlite3_value_text(argv[0]) );  /* Encoding did not change */
+  sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
+  sqlite3ChangeCookie(pParse, iDb);
 
-  if( argc==3 ){
-    /* The escape character string must consist of a single UTF-8 character.
-    ** Otherwise, return an error.
-    */
-    const unsigned char *zEsc = sqlite3_value_text(argv[2]);
-    if( zEsc==0 ) return;
-    if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){
-      sqlite3_result_error(context, 
-          "ESCAPE expression must be a single character", -1);
-      return;
-    }
-    escape = sqlite3Utf8Read(zEsc, 0, &zEsc);
+  /* If this is a virtual table, invoke the xRename() function if
+  ** one is defined. The xRename() callback will modify the names
+  ** of any resources used by the v-table implementation (including other
+  ** SQLite tables) that are identified by the name of the virtual table.
+  */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( pVTab ){
+    int i = ++pParse->nMem;
+    sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
+    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
+    sqlite3MayAbort(pParse);
   }
-  if( zA && zB ){
-    struct compareInfo *pInfo = sqlite3_user_data(context);
-#ifdef SQLITE_TEST
-    sqlite3_like_count++;
 #endif
-    
-    sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape));
-  }
-}
 
-/*
-** Implementation of the NULLIF(x,y) function.  The result is the first
-** argument if the arguments are different.  The result is NULL if the
-** arguments are equal to each other.
-*/
-static void nullifFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  CollSeq *pColl = sqlite3GetFuncCollSeq(context);
-  if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){
-    sqlite3_result_value(context, argv[0]);
+  /* figure out how many UTF-8 characters are in zName */
+  zTabName = pTab->zName;
+  nTabName = sqlite3Utf8CharLen(zTabName, -1);
+
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+  if( db->flags&SQLITE_ForeignKeys ){
+    /* If foreign-key support is enabled, rewrite the CREATE TABLE 
+    ** statements corresponding to all child tables of foreign key constraints
+    ** for which the renamed table is the parent table.  */
+    if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
+      sqlite3NestedParse(pParse, 
+          "UPDATE sqlite_master SET "
+              "sql = sqlite_rename_parent(sql, %Q, %Q) "
+              "WHERE %s;", zTabName, zName, zWhere);
+      sqlite3DbFree(db, zWhere);
+    }
   }
-}
+#endif
 
-/*
-** Implementation of the VERSION(*) function.  The result is the version
-** of the SQLite library that is running.
-*/
-static void versionFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  sqlite3_result_text(context, sqlite3_version, -1, SQLITE_STATIC);
-}
+  /* Modify the sqlite_master table to use the new table name. */
+  sqlite3NestedParse(pParse,
+      "UPDATE %Q.%s SET "
+#ifdef SQLITE_OMIT_TRIGGER
+          "sql = sqlite_rename_table(sql, %Q), "
+#else
+          "sql = CASE "
+            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
+            "ELSE sqlite_rename_table(sql, %Q) END, "
+#endif
+          "tbl_name = %Q, "
+          "name = CASE "
+            "WHEN type='table' THEN %Q "
+            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
+             "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
+            "ELSE name END "
+      "WHERE tbl_name=%Q AND "
+          "(type='table' OR type='index' OR type='trigger');", 
+      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
+#ifndef SQLITE_OMIT_TRIGGER
+      zName,
+#endif
+      zName, nTabName, zTabName
+  );
 
-/* Array for converting from half-bytes (nybbles) into ASCII hex
-** digits. */
-static const char hexdigits[] = {
-  '0', '1', '2', '3', '4', '5', '6', '7',
-  '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 
-};
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+  /* If the sqlite_sequence table exists in this database, then update 
+  ** it with the new table name.
+  */
+  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
+    sqlite3NestedParse(pParse,
+        "UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
+        zDb, zName, pTab->zName);
+  }
+#endif
 
-/*
-** EXPERIMENTAL - This is not an official function.  The interface may
-** change.  This function may disappear.  Do not write code that depends
-** on this function.
-**
-** Implementation of the QUOTE() function.  This function takes a single
-** argument.  If the argument is numeric, the return value is the same as
-** the argument.  If the argument is NULL, the return value is the string
-** "NULL".  Otherwise, the argument is enclosed in single quotes with
-** single-quote escapes.
-*/
-static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
-  if( argc<1 ) return;
-  switch( sqlite3_value_type(argv[0]) ){
-    case SQLITE_NULL: {
-      sqlite3_result_text(context, "NULL", 4, SQLITE_STATIC);
-      break;
-    }
-    case SQLITE_INTEGER:
-    case SQLITE_FLOAT: {
-      sqlite3_result_value(context, argv[0]);
-      break;
-    }
-    case SQLITE_BLOB: {
-      char *zText = 0;
-      char const *zBlob = sqlite3_value_blob(argv[0]);
-      int nBlob = sqlite3_value_bytes(argv[0]);
-      assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */
-      zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); 
-      if( zText ){
-        int i;
-        for(i=0; i<nBlob; i++){
-          zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F];
-          zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F];
-        }
-        zText[(nBlob*2)+2] = '\'';
-        zText[(nBlob*2)+3] = '\0';
-        zText[0] = 'X';
-        zText[1] = '\'';
-        sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT);
-        sqlite3_free(zText);
-      }
-      break;
-    }
-    case SQLITE_TEXT: {
-      int i,j;
-      u64 n;
-      const unsigned char *zArg = sqlite3_value_text(argv[0]);
-      char *z;
+#ifndef SQLITE_OMIT_TRIGGER
+  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
+  ** table. Don't do this if the table being ALTERed is itself located in
+  ** the temp database.
+  */
+  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
+    sqlite3NestedParse(pParse, 
+        "UPDATE sqlite_temp_master SET "
+            "sql = sqlite_rename_trigger(sql, %Q), "
+            "tbl_name = %Q "
+            "WHERE %s;", zName, zName, zWhere);
+    sqlite3DbFree(db, zWhere);
+  }
+#endif
 
-      if( zArg==0 ) return;
-      for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; }
-      z = contextMalloc(context, ((i64)i)+((i64)n)+3);
-      if( z ){
-        z[0] = '\'';
-        for(i=0, j=1; zArg[i]; i++){
-          z[j++] = zArg[i];
-          if( zArg[i]=='\'' ){
-            z[j++] = '\'';
-          }
-        }
-        z[j++] = '\'';
-        z[j] = 0;
-        sqlite3_result_text(context, z, j, sqlite3_free);
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+  if( db->flags&SQLITE_ForeignKeys ){
+    FKey *p;
+    for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
+      Table *pFrom = p->pFrom;
+      if( pFrom!=pTab ){
+        reloadTableSchema(pParse, p->pFrom, pFrom->zName);
       }
     }
   }
-}
+#endif
 
-/*
-** The hex() function.  Interpret the argument as a blob.  Return
-** a hexadecimal rendering as text.
-*/
-static void hexFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  int i, n;
-  const unsigned char *pBlob;
-  char *zHex, *z;
-  assert( argc==1 );
-  pBlob = sqlite3_value_blob(argv[0]);
-  n = sqlite3_value_bytes(argv[0]);
-  assert( pBlob==sqlite3_value_blob(argv[0]) );  /* No encoding change */
-  z = zHex = contextMalloc(context, ((i64)n)*2 + 1);
-  if( zHex ){
-    for(i=0; i<n; i++, pBlob++){
-      unsigned char c = *pBlob;
-      *(z++) = hexdigits[(c>>4)&0xf];
-      *(z++) = hexdigits[c&0xf];
-    }
-    *z = 0;
-    sqlite3_result_text(context, zHex, n*2, sqlite3_free);
-  }
+  /* Drop and reload the internal table schema. */
+  reloadTableSchema(pParse, pTab, zName);
+
+exit_rename_table:
+  sqlite3SrcListDelete(db, pSrc);
+  sqlite3DbFree(db, zName);
 }
 
+
 /*
-** The zeroblob(N) function returns a zero-filled blob of size N bytes.
+** Generate code to make sure the file format number is at least minFormat.
+** The generated code will increase the file format number if necessary.
 */
-static void zeroblobFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  i64 n;
-  assert( argc==1 );
-  n = sqlite3_value_int64(argv[0]);
-  if( n>SQLITE_MAX_LENGTH ){
-    sqlite3_result_error_toobig(context);
-  }else{
-    sqlite3_result_zeroblob(context, n);
+SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
+  Vdbe *v;
+  v = sqlite3GetVdbe(pParse);
+  /* The VDBE should have been allocated before this routine is called.
+  ** If that allocation failed, we would have quit before reaching this
+  ** point */
+  if( ALWAYS(v) ){
+    int r1 = sqlite3GetTempReg(pParse);
+    int r2 = sqlite3GetTempReg(pParse);
+    int j1;
+    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
+    sqlite3VdbeUsesBtree(v, iDb);
+    sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
+    j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
+    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2);
+    sqlite3VdbeJumpHere(v, j1);
+    sqlite3ReleaseTempReg(pParse, r1);
+    sqlite3ReleaseTempReg(pParse, r2);
   }
 }
 
 /*
-** The replace() function.  Three arguments are all strings: call
-** them A, B, and C. The result is also a string which is derived
-** from A by replacing every occurance of B with C.  The match
-** must be exact.  Collating sequences are not used.
+** This function is called after an "ALTER TABLE ... ADD" statement
+** has been parsed. Argument pColDef contains the text of the new
+** column definition.
+**
+** The Table structure pParse->pNewTable was extended to include
+** the new column during parsing.
 */
-static void replaceFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  const unsigned char *zStr;        /* The input string A */
-  const unsigned char *zPattern;    /* The pattern string B */
-  const unsigned char *zRep;        /* The replacement string C */
-  unsigned char *zOut;              /* The output */
-  int nStr;                /* Size of zStr */
-  int nPattern;            /* Size of zPattern */
-  int nRep;                /* Size of zRep */
-  i64 nOut;                /* Maximum size of zOut */
-  int loopLimit;           /* Last zStr[] that might match zPattern[] */
-  int i, j;                /* Loop counters */
+SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
+  Table *pNew;              /* Copy of pParse->pNewTable */
+  Table *pTab;              /* Table being altered */
+  int iDb;                  /* Database number */
+  const char *zDb;          /* Database name */
+  const char *zTab;         /* Table name */
+  char *zCol;               /* Null-terminated column definition */
+  Column *pCol;             /* The new column */
+  Expr *pDflt;              /* Default value for the new column */
+  sqlite3 *db;              /* The database connection; */
 
-  assert( argc==3 );
-  zStr = sqlite3_value_text(argv[0]);
-  if( zStr==0 ) return;
-  nStr = sqlite3_value_bytes(argv[0]);
-  assert( zStr==sqlite3_value_text(argv[0]) );  /* No encoding change */
-  zPattern = sqlite3_value_text(argv[1]);
-  if( zPattern==0 || zPattern[0]==0 ) return;
-  nPattern = sqlite3_value_bytes(argv[1]);
-  assert( zPattern==sqlite3_value_text(argv[1]) );  /* No encoding change */
-  zRep = sqlite3_value_text(argv[2]);
-  if( zRep==0 ) return;
-  nRep = sqlite3_value_bytes(argv[2]);
-  assert( zRep==sqlite3_value_text(argv[2]) );
-  nOut = nStr + 1;
-  assert( nOut<SQLITE_MAX_LENGTH );
-  zOut = contextMalloc(context, (i64)nOut);
-  if( zOut==0 ){
+  db = pParse->db;
+  if( pParse->nErr || db->mallocFailed ) return;
+  pNew = pParse->pNewTable;
+  assert( pNew );
+
+  assert( sqlite3BtreeHoldsAllMutexes(db) );
+  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
+  zDb = db->aDb[iDb].zName;
+  zTab = &pNew->zName[16];  /* Skip the "sqlite_altertab_" prefix on the name */
+  pCol = &pNew->aCol[pNew->nCol-1];
+  pDflt = pCol->pDflt;
+  pTab = sqlite3FindTable(db, zTab, zDb);
+  assert( pTab );
+
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  /* Invoke the authorization callback. */
+  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
     return;
   }
-  loopLimit = nStr - nPattern;  
-  for(i=j=0; i<=loopLimit; i++){
-    if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){
-      zOut[j++] = zStr[i];
-    }else{
-      u8 *zOld;
-      sqlite3 *db = sqlite3_context_db_handle(context);
-      nOut += nRep - nPattern;
-      if( nOut>=db->aLimit[SQLITE_LIMIT_LENGTH] ){
-        sqlite3_result_error_toobig(context);
-        sqlite3_free(zOut);
-        return;
-      }
-      zOld = zOut;
-      zOut = sqlite3_realloc(zOut, (int)nOut);
-      if( zOut==0 ){
-        sqlite3_result_error_nomem(context);
-        sqlite3_free(zOld);
-        return;
-      }
-      memcpy(&zOut[j], zRep, nRep);
-      j += nRep;
-      i += nPattern-1;
-    }
-  }
-  assert( j+nStr-i+1==nOut );
-  memcpy(&zOut[j], &zStr[i], nStr-i);
-  j += nStr - i;
-  assert( j<=nOut );
-  zOut[j] = 0;
-  sqlite3_result_text(context, (char*)zOut, j, sqlite3_free);
-}
+#endif
 
-/*
-** Implementation of the TRIM(), LTRIM(), and RTRIM() functions.
-** The userdata is 0x1 for left trim, 0x2 for right trim, 0x3 for both.
-*/
-static void trimFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  const unsigned char *zIn;         /* Input string */
-  const unsigned char *zCharSet;    /* Set of characters to trim */
-  int nIn;                          /* Number of bytes in input */
-  int flags;                        /* 1: trimleft  2: trimright  3: trim */
-  int i;                            /* Loop counter */
-  unsigned char *aLen;              /* Length of each character in zCharSet */
-  unsigned char **azChar;           /* Individual characters in zCharSet */
-  int nChar;                        /* Number of characters in zCharSet */
+  /* If the default value for the new column was specified with a 
+  ** literal NULL, then set pDflt to 0. This simplifies checking
+  ** for an SQL NULL default below.
+  */
+  if( pDflt && pDflt->op==TK_NULL ){
+    pDflt = 0;
+  }
 
-  if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
+  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
+  ** If there is a NOT NULL constraint, then the default value for the
+  ** column must not be NULL.
+  */
+  if( pCol->isPrimKey ){
+    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
     return;
   }
-  zIn = sqlite3_value_text(argv[0]);
-  if( zIn==0 ) return;
-  nIn = sqlite3_value_bytes(argv[0]);
-  assert( zIn==sqlite3_value_text(argv[0]) );
-  if( argc==1 ){
-    static const unsigned char lenOne[] = { 1 };
-    static const unsigned char *azOne[] = { (u8*)" " };
-    nChar = 1;
-    aLen = (u8*)lenOne;
-    azChar = (unsigned char **)azOne;
-    zCharSet = 0;
-  }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){
+  if( pNew->pIndex ){
+    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
     return;
-  }else{
-    const unsigned char *z;
-    for(z=zCharSet, nChar=0; *z; nChar++){
-      SQLITE_SKIP_UTF8(z);
-    }
-    if( nChar>0 ){
-      azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1));
-      if( azChar==0 ){
-        return;
-      }
-      aLen = (unsigned char*)&azChar[nChar];
-      for(z=zCharSet, nChar=0; *z; nChar++){
-        azChar[nChar] = (unsigned char *)z;
-        SQLITE_SKIP_UTF8(z);
-        aLen[nChar] = z - azChar[nChar];
-      }
-    }
   }
-  if( nChar>0 ){
-    flags = (int)sqlite3_user_data(context);
-    if( flags & 1 ){
-      while( nIn>0 ){
-        int len;
-        for(i=0; i<nChar; i++){
-          len = aLen[i];
-          if( memcmp(zIn, azChar[i], len)==0 ) break;
-        }
-        if( i>=nChar ) break;
-        zIn += len;
-        nIn -= len;
-      }
-    }
-    if( flags & 2 ){
-      while( nIn>0 ){
-        int len;
-        for(i=0; i<nChar; i++){
-          len = aLen[i];
-          if( len<=nIn && memcmp(&zIn[nIn-len],azChar[i],len)==0 ) break;
-        }
-        if( i>=nChar ) break;
-        nIn -= len;
-      }
+  if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
+    sqlite3ErrorMsg(pParse, 
+        "Cannot add a REFERENCES column with non-NULL default value");
+    return;
+  }
+  if( pCol->notNull && !pDflt ){
+    sqlite3ErrorMsg(pParse, 
+        "Cannot add a NOT NULL column with default value NULL");
+    return;
+  }
+
+  /* Ensure the default expression is something that sqlite3ValueFromExpr()
+  ** can handle (i.e. not CURRENT_TIME etc.)
+  */
+  if( pDflt ){
+    sqlite3_value *pVal;
+    if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
+      db->mallocFailed = 1;
+      return;
     }
-    if( zCharSet ){
-      sqlite3_free(azChar);
+    if( !pVal ){
+      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
+      return;
     }
+    sqlite3ValueFree(pVal);
   }
-  sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
-}
 
-#ifdef SQLITE_SOUNDEX
-/*
-** Compute the soundex encoding of a word.
-*/
-static void soundexFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  char zResult[8];
-  const u8 *zIn;
-  int i, j;
-  static const unsigned char iCode[] = {
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0,
-    1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0,
-    0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0,
-    1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0,
-  };
-  assert( argc==1 );
-  zIn = (u8*)sqlite3_value_text(argv[0]);
-  if( zIn==0 ) zIn = (u8*)"";
-  for(i=0; zIn[i] && !isalpha(zIn[i]); i++){}
-  if( zIn[i] ){
-    u8 prevcode = iCode[zIn[i]&0x7f];
-    zResult[0] = toupper(zIn[i]);
-    for(j=1; j<4 && zIn[i]; i++){
-      int code = iCode[zIn[i]&0x7f];
-      if( code>0 ){
-        if( code!=prevcode ){
-          prevcode = code;
-          zResult[j++] = code + '0';
-        }
-      }else{
-        prevcode = 0;
-      }
-    }
-    while( j<4 ){
-      zResult[j++] = '0';
+  /* Modify the CREATE TABLE statement. */
+  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
+  if( zCol ){
+    char *zEnd = &zCol[pColDef->n-1];
+    while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
+      *zEnd-- = '\0';
     }
-    zResult[j] = 0;
-    sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT);
-  }else{
-    sqlite3_result_text(context, "?000", 4, SQLITE_STATIC);
+    sqlite3NestedParse(pParse, 
+        "UPDATE \"%w\".%s SET "
+          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
+        "WHERE type = 'table' AND name = %Q", 
+      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
+      zTab
+    );
+    sqlite3DbFree(db, zCol);
   }
+
+  /* If the default value of the new column is NULL, then set the file
+  ** format to 2. If the default value of the new column is not NULL,
+  ** the file format becomes 3.
+  */
+  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
+
+  /* Reload the schema of the modified table. */
+  reloadTableSchema(pParse, pTab, pTab->zName);
 }
-#endif
 
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
 /*
-** A function that loads a shared-library extension then returns NULL.
+** This function is called by the parser after the table-name in
+** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument 
+** pSrc is the full-name of the table being altered.
+**
+** This routine makes a (partial) copy of the Table structure
+** for the table being altered and sets Parse.pNewTable to point
+** to it. Routines called by the parser as the column definition
+** is parsed (i.e. sqlite3AddColumn()) add the new Column data to 
+** the copy. The copy of the Table structure is deleted by tokenize.c 
+** after parsing is finished.
+**
+** Routine sqlite3AlterFinishAddColumn() will be called to complete
+** coding the "ALTER TABLE ... ADD" statement.
 */
-static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){
-  const char *zFile = (const char *)sqlite3_value_text(argv[0]);
-  const char *zProc;
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  char *zErrMsg = 0;
+SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
+  Table *pNew;
+  Table *pTab;
+  Vdbe *v;
+  int iDb;
+  int i;
+  int nAlloc;
+  sqlite3 *db = pParse->db;
 
-  if( argc==2 ){
-    zProc = (const char *)sqlite3_value_text(argv[1]);
-  }else{
-    zProc = 0;
-  }
-  if( zFile && sqlite3_load_extension(db, zFile, zProc, &zErrMsg) ){
-    sqlite3_result_error(context, zErrMsg, -1);
-    sqlite3_free(zErrMsg);
+  /* Look up the table being altered. */
+  assert( pParse->pNewTable==0 );
+  assert( sqlite3BtreeHoldsAllMutexes(db) );
+  if( db->mallocFailed ) goto exit_begin_add_column;
+  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  if( !pTab ) goto exit_begin_add_column;
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( IsVirtual(pTab) ){
+    sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
+    goto exit_begin_add_column;
   }
-}
 #endif
 
+  /* Make sure this is not an attempt to ALTER a view. */
+  if( pTab->pSelect ){
+    sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
+    goto exit_begin_add_column;
+  }
 
-/*
-** An instance of the following structure holds the context of a
-** sum() or avg() aggregate computation.
-*/
-typedef struct SumCtx SumCtx;
-struct SumCtx {
-  double rSum;      /* Floating point sum */
-  i64 iSum;         /* Integer sum */   
-  i64 cnt;          /* Number of elements summed */
-  u8 overflow;      /* True if integer overflow seen */
-  u8 approx;        /* True if non-integer value was input to the sum */
-};
+  assert( pTab->addColOffset>0 );
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
 
-/*
-** Routines used to compute the sum, average, and total.
-**
-** The SUM() function follows the (broken) SQL standard which means
-** that it returns NULL if it sums over no inputs.  TOTAL returns
-** 0.0 in that case.  In addition, TOTAL always returns a float where
-** SUM might return an integer if it never encounters a floating point
-** value.  TOTAL never fails, but SUM might through an exception if
-** it overflows an integer.
-*/
-static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){
-  SumCtx *p;
-  int type;
-  assert( argc==1 );
-  p = sqlite3_aggregate_context(context, sizeof(*p));
-  type = sqlite3_value_numeric_type(argv[0]);
-  if( p && type!=SQLITE_NULL ){
-    p->cnt++;
-    if( type==SQLITE_INTEGER ){
-      i64 v = sqlite3_value_int64(argv[0]);
-      p->rSum += v;
-      if( (p->approx|p->overflow)==0 ){
-        i64 iNewSum = p->iSum + v;
-        int s1 = p->iSum >> (sizeof(i64)*8-1);
-        int s2 = v       >> (sizeof(i64)*8-1);
-        int s3 = iNewSum >> (sizeof(i64)*8-1);
-        p->overflow = (s1&s2&~s3) | (~s1&~s2&s3);
-        p->iSum = iNewSum;
-      }
-    }else{
-      p->rSum += sqlite3_value_double(argv[0]);
-      p->approx = 1;
-    }
-  }
-}
-static void sumFinalize(sqlite3_context *context){
-  SumCtx *p;
-  p = sqlite3_aggregate_context(context, 0);
-  if( p && p->cnt>0 ){
-    if( p->overflow ){
-      sqlite3_result_error(context,"integer overflow",-1);
-    }else if( p->approx ){
-      sqlite3_result_double(context, p->rSum);
-    }else{
-      sqlite3_result_int64(context, p->iSum);
-    }
+  /* Put a copy of the Table struct in Parse.pNewTable for the
+  ** sqlite3AddColumn() function and friends to modify.  But modify
+  ** the name by adding an "sqlite_altertab_" prefix.  By adding this
+  ** prefix, we insure that the name will not collide with an existing
+  ** table because user table are not allowed to have the "sqlite_"
+  ** prefix on their name.
+  */
+  pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
+  if( !pNew ) goto exit_begin_add_column;
+  pParse->pNewTable = pNew;
+  pNew->nRef = 1;
+  pNew->dbMem = pTab->dbMem;
+  pNew->nCol = pTab->nCol;
+  assert( pNew->nCol>0 );
+  nAlloc = (((pNew->nCol-1)/8)*8)+8;
+  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
+  pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
+  pNew->zName = sqlite3MPrintf(db, "sqlite_altertab_%s", pTab->zName);
+  if( !pNew->aCol || !pNew->zName ){
+    db->mallocFailed = 1;
+    goto exit_begin_add_column;
   }
-}
-static void avgFinalize(sqlite3_context *context){
-  SumCtx *p;
-  p = sqlite3_aggregate_context(context, 0);
-  if( p && p->cnt>0 ){
-    sqlite3_result_double(context, p->rSum/(double)p->cnt);
+  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
+  for(i=0; i<pNew->nCol; i++){
+    Column *pCol = &pNew->aCol[i];
+    pCol->zName = sqlite3DbStrDup(db, pCol->zName);
+    pCol->zColl = 0;
+    pCol->zType = 0;
+    pCol->pDflt = 0;
+    pCol->zDflt = 0;
   }
-}
-static void totalFinalize(sqlite3_context *context){
-  SumCtx *p;
-  p = sqlite3_aggregate_context(context, 0);
-  sqlite3_result_double(context, p ? p->rSum : 0.0);
-}
+  pNew->pSchema = db->aDb[iDb].pSchema;
+  pNew->addColOffset = pTab->addColOffset;
+  pNew->nRef = 1;
 
-/*
-** The following structure keeps track of state information for the
-** count() aggregate function.
-*/
-typedef struct CountCtx CountCtx;
-struct CountCtx {
-  i64 n;
-};
+  /* Begin a transaction and increment the schema cookie.  */
+  sqlite3BeginWriteOperation(pParse, 0, iDb);
+  v = sqlite3GetVdbe(pParse);
+  if( !v ) goto exit_begin_add_column;
+  sqlite3ChangeCookie(pParse, iDb);
 
-/*
-** Routines to implement the count() aggregate function.
-*/
-static void countStep(sqlite3_context *context, int argc, sqlite3_value **argv){
-  CountCtx *p;
-  p = sqlite3_aggregate_context(context, sizeof(*p));
-  if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && p ){
-    p->n++;
-  }
-}   
-static void countFinalize(sqlite3_context *context){
-  CountCtx *p;
-  p = sqlite3_aggregate_context(context, 0);
-  sqlite3_result_int64(context, p ? p->n : 0);
+exit_begin_add_column:
+  sqlite3SrcListDelete(db, pSrc);
+  return;
 }
+#endif  /* SQLITE_ALTER_TABLE */
 
+/************** End of alter.c ***********************************************/
+/************** Begin file analyze.c *****************************************/
 /*
-** Routines to implement min() and max() aggregate functions.
+** 2005 July 8
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code associated with the ANALYZE command.
+**
+** @(#) $Id: analyze.c,v 1.52 2009/04/16 17:45:48 drh Exp $
 */
-static void minmaxStep(sqlite3_context *context, int argc, sqlite3_value **argv){
-  Mem *pArg  = (Mem *)argv[0];
-  Mem *pBest;
-
-  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
-  pBest = (Mem *)sqlite3_aggregate_context(context, sizeof(*pBest));
-  if( !pBest ) return;
-
-  if( pBest->flags ){
-    int max;
-    int cmp;
-    CollSeq *pColl = sqlite3GetFuncCollSeq(context);
-    /* This step function is used for both the min() and max() aggregates,
-    ** the only difference between the two being that the sense of the
-    ** comparison is inverted. For the max() aggregate, the
-    ** sqlite3_user_data() function returns (void *)-1. For min() it
-    ** returns (void *)db, where db is the sqlite3* database pointer.
-    ** Therefore the next statement sets variable 'max' to 1 for the max()
-    ** aggregate, or 0 for min().
-    */
-    max = sqlite3_user_data(context)!=0;
-    cmp = sqlite3MemCompare(pBest, pArg, pColl);
-    if( (max && cmp<0) || (!max && cmp>0) ){
-      sqlite3VdbeMemCopy(pBest, pArg);
-    }
-  }else{
-    sqlite3VdbeMemCopy(pBest, pArg);
-  }
-}
-static void minMaxFinalize(sqlite3_context *context){
-  sqlite3_value *pRes;
-  pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0);
-  if( pRes ){
-    if( pRes->flags ){
-      sqlite3_result_value(context, pRes);
-    }
-    sqlite3VdbeMemRelease(pRes);
-  }
-}
+#ifndef SQLITE_OMIT_ANALYZE
 
 /*
-** group_concat(EXPR, ?SEPARATOR?)
+** This routine generates code that opens the sqlite_stat1 table for
+** writing with cursor iStatCur. If the library was built with the
+** SQLITE_ENABLE_STAT2 macro defined, then the sqlite_stat2 table is
+** opened for writing using cursor (iStatCur+1)
+**
+** If the sqlite_stat1 tables does not previously exist, it is created.
+** Similarly, if the sqlite_stat2 table does not exist and the library
+** is compiled with SQLITE_ENABLE_STAT2 defined, it is created. 
+**
+** Argument zWhere may be a pointer to a buffer containing a table name,
+** or it may be a NULL pointer. If it is not NULL, then all entries in
+** the sqlite_stat1 and (if applicable) sqlite_stat2 tables associated
+** with the named table are deleted. If zWhere==0, then code is generated
+** to delete all stat table entries.
 */
-static void groupConcatStep(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+static void openStatTable(
+  Parse *pParse,          /* Parsing context */
+  int iDb,                /* The database we are looking in */
+  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
+  const char *zWhere      /* Delete entries associated with this table */
 ){
-  const char *zVal;
-  StrAccum *pAccum;
-  const char *zSep;
-  int nVal, nSep;
-  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
-  pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum));
+  static struct {
+    const char *zName;
+    const char *zCols;
+  } aTable[] = {
+    { "sqlite_stat1", "tbl,idx,stat" },
+#ifdef SQLITE_ENABLE_STAT2
+    { "sqlite_stat2", "tbl,idx,sampleno,sample" },
+#endif
+  };
 
-  if( pAccum ){
-    sqlite3 *db = sqlite3_context_db_handle(context);
-    pAccum->useMalloc = 1;
-    pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
-    if( pAccum->nChar ){
-      if( argc==2 ){
-        zSep = (char*)sqlite3_value_text(argv[1]);
-        nSep = sqlite3_value_bytes(argv[1]);
+  int aRoot[] = {0, 0};
+  u8 aCreateTbl[] = {0, 0};
+
+  int i;
+  sqlite3 *db = pParse->db;
+  Db *pDb;
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( v==0 ) return;
+  assert( sqlite3BtreeHoldsAllMutexes(db) );
+  assert( sqlite3VdbeDb(v)==db );
+  pDb = &db->aDb[iDb];
+
+  for(i=0; i<ArraySize(aTable); i++){
+    const char *zTab = aTable[i].zName;
+    Table *pStat;
+    if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){
+      /* The sqlite_stat[12] table does not exist. Create it. Note that a 
+      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
+      ** of the new table in register pParse->regRoot. This is important 
+      ** because the OpenWrite opcode below will be needing it. */
+      sqlite3NestedParse(pParse,
+          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
+      );
+      aRoot[i] = pParse->regRoot;
+      aCreateTbl[i] = 1;
+    }else{
+      /* The table already exists. If zWhere is not NULL, delete all entries 
+      ** associated with the table zWhere. If zWhere is NULL, delete the
+      ** entire contents of the table. */
+      aRoot[i] = pStat->tnum;
+      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
+      if( zWhere ){
+        sqlite3NestedParse(pParse,
+           "DELETE FROM %Q.%s WHERE tbl=%Q", pDb->zName, zTab, zWhere
+        );
       }else{
-        zSep = ",";
-        nSep = 1;
+        /* The sqlite_stat[12] table already exists.  Delete all rows. */
+        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
       }
-      sqlite3StrAccumAppend(pAccum, zSep, nSep);
     }
-    zVal = (char*)sqlite3_value_text(argv[0]);
-    nVal = sqlite3_value_bytes(argv[0]);
-    sqlite3StrAccumAppend(pAccum, zVal, nVal);
   }
-}
-static void groupConcatFinalize(sqlite3_context *context){
-  StrAccum *pAccum;
-  pAccum = sqlite3_aggregate_context(context, 0);
-  if( pAccum ){
-    if( pAccum->tooBig ){
-      sqlite3_result_error_toobig(context);
-    }else if( pAccum->mallocFailed ){
-      sqlite3_result_error_nomem(context);
-    }else{    
-      sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, 
-                          sqlite3_free);
-    }
+
+  /* Open the sqlite_stat[12] tables for writing. */
+  for(i=0; i<ArraySize(aTable); i++){
+    sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
+    sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
+    sqlite3VdbeChangeP5(v, aCreateTbl[i]);
   }
 }
 
 /*
-** This function registered all of the above C functions as SQL
-** functions.  This should be the only routine in this file with
-** external linkage.
+** Generate code to do an analysis of all indices associated with
+** a single table.
 */
-SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
-  static const struct {
-     char *zName;
-     signed char nArg;
-     u8 argType;           /* 1: 0, 2: 1, 3: 2,...  N:  N-1. */
-     u8 eTextRep;          /* 1: UTF-16.  0: UTF-8 */
-     u8 needCollSeq;
-     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
-  } aFuncs[] = {
-    { "min",               -1, 0, SQLITE_UTF8,    1, minmaxFunc },
-    { "min",                0, 0, SQLITE_UTF8,    1, 0          },
-    { "max",               -1, 1, SQLITE_UTF8,    1, minmaxFunc },
-    { "max",                0, 1, SQLITE_UTF8,    1, 0          },
-    { "typeof",             1, 0, SQLITE_UTF8,    0, typeofFunc },
-    { "length",             1, 0, SQLITE_UTF8,    0, lengthFunc },
-    { "substr",             2, 0, SQLITE_UTF8,    0, substrFunc },
-    { "substr",             3, 0, SQLITE_UTF8,    0, substrFunc },
-    { "abs",                1, 0, SQLITE_UTF8,    0, absFunc    },
-    { "round",              1, 0, SQLITE_UTF8,    0, roundFunc  },
-    { "round",              2, 0, SQLITE_UTF8,    0, roundFunc  },
-    { "upper",              1, 0, SQLITE_UTF8,    0, upperFunc  },
-    { "lower",              1, 0, SQLITE_UTF8,    0, lowerFunc  },
-    { "coalesce",          -1, 0, SQLITE_UTF8,    0, ifnullFunc },
-    { "coalesce",           0, 0, SQLITE_UTF8,    0, 0          },
-    { "coalesce",           1, 0, SQLITE_UTF8,    0, 0          },
-    { "hex",                1, 0, SQLITE_UTF8,    0, hexFunc    },
-    { "ifnull",             2, 0, SQLITE_UTF8,    1, ifnullFunc },
-    { "random",            -1, 0, SQLITE_UTF8,    0, randomFunc },
-    { "randomblob",         1, 0, SQLITE_UTF8,    0, randomBlob },
-    { "nullif",             2, 0, SQLITE_UTF8,    1, nullifFunc },
-    { "sqlite_version",     0, 0, SQLITE_UTF8,    0, versionFunc},
-    { "quote",              1, 0, SQLITE_UTF8,    0, quoteFunc  },
-    { "last_insert_rowid",  0, 0, SQLITE_UTF8, 0, last_insert_rowid },
-    { "changes",            0, 0, SQLITE_UTF8, 0, changes           },
-    { "total_changes",      0, 0, SQLITE_UTF8, 0, total_changes     },
-    { "replace",            3, 0, SQLITE_UTF8,    0, replaceFunc       },
-    { "ltrim",              1, 1, SQLITE_UTF8,    0, trimFunc          },
-    { "ltrim",              2, 1, SQLITE_UTF8,    0, trimFunc          },
-    { "rtrim",              1, 2, SQLITE_UTF8,    0, trimFunc          },
-    { "rtrim",              2, 2, SQLITE_UTF8,    0, trimFunc          },
-    { "trim",               1, 3, SQLITE_UTF8,    0, trimFunc          },
-    { "trim",               2, 3, SQLITE_UTF8,    0, trimFunc          },
-    { "zeroblob",           1, 0, SQLITE_UTF8,    0, zeroblobFunc      },
-#ifdef SQLITE_SOUNDEX
-    { "soundex",            1, 0, SQLITE_UTF8,    0, soundexFunc},
-#endif
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
-    { "load_extension",     1, 0, SQLITE_UTF8, 0, loadExt },
-    { "load_extension",     2, 0, SQLITE_UTF8, 0, loadExt },
+static void analyzeOneTable(
+  Parse *pParse,   /* Parser context */
+  Table *pTab,     /* Table whose indices are to be analyzed */
+  int iStatCur,    /* Index of VdbeCursor that writes the sqlite_stat1 table */
+  int iMem         /* Available memory locations begin here */
+){
+  sqlite3 *db = pParse->db;    /* Database handle */
+  Index *pIdx;                 /* An index to being analyzed */
+  int iIdxCur;                 /* Cursor open on index being analyzed */
+  Vdbe *v;                     /* The virtual machine being built up */
+  int i;                       /* Loop counter */
+  int topOfLoop;               /* The top of the loop */
+  int endOfLoop;               /* The end of the loop */
+  int addr;                    /* The address of an instruction */
+  int iDb;                     /* Index of database containing pTab */
+  int regTabname = iMem++;     /* Register containing table name */
+  int regIdxname = iMem++;     /* Register containing index name */
+  int regSampleno = iMem++;    /* Register containing next sample number */
+  int regCol = iMem++;         /* Content of a column analyzed table */
+  int regRec = iMem++;         /* Register holding completed record */
+  int regTemp = iMem++;        /* Temporary use register */
+  int regRowid = iMem++;       /* Rowid for the inserted record */
+
+#ifdef SQLITE_ENABLE_STAT2
+  int regTemp2 = iMem++;       /* Temporary use register */
+  int regSamplerecno = iMem++; /* Index of next sample to record */
+  int regRecno = iMem++;       /* Current sample index */
+  int regLast = iMem++;        /* Index of last sample to record */
+  int regFirst = iMem++;       /* Index of first sample to record */
 #endif
-  };
-  static const struct {
-    char *zName;
-    signed char nArg;
-    u8 argType;
-    u8 needCollSeq;
-    void (*xStep)(sqlite3_context*,int,sqlite3_value**);
-    void (*xFinalize)(sqlite3_context*);
-  } aAggs[] = {
-    { "min",    1, 0, 1, minmaxStep,   minMaxFinalize },
-    { "max",    1, 1, 1, minmaxStep,   minMaxFinalize },
-    { "sum",    1, 0, 0, sumStep,      sumFinalize    },
-    { "total",  1, 0, 0, sumStep,      totalFinalize    },
-    { "avg",    1, 0, 0, sumStep,      avgFinalize    },
-    { "count",  0, 0, 0, countStep,    countFinalize  },
-    { "count",  1, 0, 0, countStep,    countFinalize  },
-    { "group_concat", 1, 0, 0, groupConcatStep, groupConcatFinalize },
-    { "group_concat", 2, 0, 0, groupConcatStep, groupConcatFinalize },
-  };
-  int i;
 
-  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
-    void *pArg;
-    u8 argType = aFuncs[i].argType;
-    pArg = (void*)(int)argType;
-    sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
-        aFuncs[i].eTextRep, pArg, aFuncs[i].xFunc, 0, 0);
-    if( aFuncs[i].needCollSeq ){
-      FuncDef *pFunc = sqlite3FindFunction(db, aFuncs[i].zName, 
-          strlen(aFuncs[i].zName), aFuncs[i].nArg, aFuncs[i].eTextRep, 0);
-      if( pFunc && aFuncs[i].needCollSeq ){
-        pFunc->needCollSeq = 1;
-      }
-    }
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 || NEVER(pTab==0) || pTab->pIndex==0 ){
+    /* Do no analysis for tables that have no indices */
+    return;
+  }
+  assert( sqlite3BtreeHoldsAllMutexes(db) );
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  assert( iDb>=0 );
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
+      db->aDb[iDb].zName ) ){
+    return;
   }
-#ifndef SQLITE_OMIT_ALTERTABLE
-  sqlite3AlterFunctions(db);
 #endif
-#ifndef SQLITE_OMIT_PARSER
-  sqlite3AttachFunctions(db);
+
+  /* Establish a read-lock on the table at the shared-cache level. */
+  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
+
+  iIdxCur = pParse->nTab++;
+  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+    int nCol = pIdx->nColumn;
+    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
+
+    if( iMem+1+(nCol*2)>pParse->nMem ){
+      pParse->nMem = iMem+1+(nCol*2);
+    }
+
+    /* Open a cursor to the index to be analyzed. */
+    assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
+    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
+        (char *)pKey, P4_KEYINFO_HANDOFF);
+    VdbeComment((v, "%s", pIdx->zName));
+
+    /* Populate the registers containing the table and index names. */
+    if( pTab->pIndex==pIdx ){
+      sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
+    }
+    sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
+
+#ifdef SQLITE_ENABLE_STAT2
+
+    /* If this iteration of the loop is generating code to analyze the
+    ** first index in the pTab->pIndex list, then register regLast has
+    ** not been populated. In this case populate it now.  */
+    if( pTab->pIndex==pIdx ){
+      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regSamplerecno);
+      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2-1, regTemp);
+      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2, regTemp2);
+
+      sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regLast);
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regFirst);
+      addr = sqlite3VdbeAddOp3(v, OP_Lt, regSamplerecno, 0, regLast);
+      sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regFirst);
+      sqlite3VdbeAddOp3(v, OP_Multiply, regLast, regTemp, regLast);
+      sqlite3VdbeAddOp2(v, OP_AddImm, regLast, SQLITE_INDEX_SAMPLES*2-2);
+      sqlite3VdbeAddOp3(v, OP_Divide,  regTemp2, regLast, regLast);
+      sqlite3VdbeJumpHere(v, addr);
+    }
+
+    /* Zero the regSampleno and regRecno registers. */
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regSampleno);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRecno);
+    sqlite3VdbeAddOp2(v, OP_Copy, regFirst, regSamplerecno);
 #endif
-  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
-    void *pArg = (void*)(int)aAggs[i].argType;
-    sqlite3CreateFunc(db, aAggs[i].zName, aAggs[i].nArg, SQLITE_UTF8, 
-        pArg, 0, aAggs[i].xStep, aAggs[i].xFinalize);
-    if( aAggs[i].needCollSeq ){
-      FuncDef *pFunc = sqlite3FindFunction( db, aAggs[i].zName,
-          strlen(aAggs[i].zName), aAggs[i].nArg, SQLITE_UTF8, 0);
-      if( pFunc && aAggs[i].needCollSeq ){
-        pFunc->needCollSeq = 1;
+
+    /* The block of memory cells initialized here is used as follows.
+    **
+    **    iMem:                
+    **        The total number of rows in the table.
+    **
+    **    iMem+1 .. iMem+nCol: 
+    **        Number of distinct entries in index considering the 
+    **        left-most N columns only, where N is between 1 and nCol, 
+    **        inclusive.
+    **
+    **    iMem+nCol+1 .. Mem+2*nCol:  
+    **        Previous value of indexed columns, from left to right.
+    **
+    ** Cells iMem through iMem+nCol are initialized to 0. The others are 
+    ** initialized to contain an SQL NULL.
+    */
+    for(i=0; i<=nCol; i++){
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
+    }
+    for(i=0; i<nCol; i++){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
+    }
+
+    /* Start the analysis loop. This loop runs through all the entries in
+    ** the index b-tree.  */
+    endOfLoop = sqlite3VdbeMakeLabel(v);
+    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
+    topOfLoop = sqlite3VdbeCurrentAddr(v);
+    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
+
+    for(i=0; i<nCol; i++){
+      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
+#ifdef SQLITE_ENABLE_STAT2
+      if( i==0 ){
+        /* Check if the record that cursor iIdxCur points to contains a
+        ** value that should be stored in the sqlite_stat2 table. If so,
+        ** store it.  */
+        int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
+        assert( regTabname+1==regIdxname 
+             && regTabname+2==regSampleno
+             && regTabname+3==regCol
+        );
+        sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 4, regRec, "aaab", 0);
+        sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regRowid);
+        sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regRowid);
+
+        /* Calculate new values for regSamplerecno and regSampleno.
+        **
+        **   sampleno = sampleno + 1
+        **   samplerecno = samplerecno+(remaining records)/(remaining samples)
+        */
+        sqlite3VdbeAddOp2(v, OP_AddImm, regSampleno, 1);
+        sqlite3VdbeAddOp3(v, OP_Subtract, regRecno, regLast, regTemp);
+        sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
+        sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regTemp2);
+        sqlite3VdbeAddOp3(v, OP_Subtract, regSampleno, regTemp2, regTemp2);
+        sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regTemp, regTemp);
+        sqlite3VdbeAddOp3(v, OP_Add, regSamplerecno, regTemp, regSamplerecno);
+
+        sqlite3VdbeJumpHere(v, ne);
+        sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
       }
+#endif
+
+      sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
+      /**** TODO:  add collating sequence *****/
+      sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
     }
-  }
-  sqlite3RegisterDateTimeFunctions(db);
-  if( !db->mallocFailed ){
-    int rc = sqlite3_overload_function(db, "MATCH", 2);
-    assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
-    if( rc==SQLITE_NOMEM ){
-      db->mallocFailed = 1;
+    if( db->mallocFailed ){
+      /* If a malloc failure has occurred, then the result of the expression 
+      ** passed as the second argument to the call to sqlite3VdbeJumpHere() 
+      ** below may be negative. Which causes an assert() to fail (or an
+      ** out-of-bounds write if SQLITE_DEBUG is not defined).  */
+      return;
+    }
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
+    for(i=0; i<nCol; i++){
+      sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-(nCol*2));
+      sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
+      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
+    }
+
+    /* End of the analysis loop. */
+    sqlite3VdbeResolveLabel(v, endOfLoop);
+    sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
+    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
+
+    /* Store the results in sqlite_stat1.
+    **
+    ** The result is a single row of the sqlite_stat1 table.  The first
+    ** two columns are the names of the table and index.  The third column
+    ** is a string composed of a list of integer statistics about the
+    ** index.  The first integer in the list is the total number of entries
+    ** in the index.  There is one additional integer in the list for each
+    ** column of the table.  This additional integer is a guess of how many
+    ** rows of the table the index will select.  If D is the count of distinct
+    ** values and K is the total number of rows, then the integer is computed
+    ** as:
+    **
+    **        I = (K+D-1)/D
+    **
+    ** If K==0 then no entry is made into the sqlite_stat1 table.  
+    ** If K>0 then it is always the case the D>0 so division by zero
+    ** is never possible.
+    */
+    addr = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
+    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
+    for(i=0; i<nCol; i++){
+      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
+      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
+      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
+      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
+      sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
+      sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
+      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
     }
+    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
+    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
+    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
+    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+    sqlite3VdbeJumpHere(v, addr);
   }
-#ifdef SQLITE_SSE
-  (void)sqlite3SseFunctions(db);
-#endif
-#ifdef SQLITE_CASE_SENSITIVE_LIKE
-  sqlite3RegisterLikeFunctions(db, 1);
-#else
-  sqlite3RegisterLikeFunctions(db, 0);
-#endif
 }
 
 /*
-** Set the LIKEOPT flag on the 2-argument function with the given name.
+** Generate code that will cause the most recent index analysis to
+** be laoded into internal hash tables where is can be used.
 */
-static void setLikeOptFlag(sqlite3 *db, const char *zName, int flagVal){
-  FuncDef *pDef;
-  pDef = sqlite3FindFunction(db, zName, strlen(zName), 2, SQLITE_UTF8, 0);
-  if( pDef ){
-    pDef->flags = flagVal;
+static void loadAnalysis(Parse *pParse, int iDb){
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( v ){
+    sqlite3VdbeAddOp1(v, OP_LoadAnalysis, iDb);
   }
 }
 
 /*
-** Register the built-in LIKE and GLOB functions.  The caseSensitive
-** parameter determines whether or not the LIKE operator is case
-** sensitive.  GLOB is always case sensitive.
+** Generate code that will do an analysis of an entire database
 */
-SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){
-  struct compareInfo *pInfo;
-  if( caseSensitive ){
-    pInfo = (struct compareInfo*)&likeInfoAlt;
-  }else{
-    pInfo = (struct compareInfo*)&likeInfoNorm;
+static void analyzeDatabase(Parse *pParse, int iDb){
+  sqlite3 *db = pParse->db;
+  Schema *pSchema = db->aDb[iDb].pSchema;    /* Schema of database iDb */
+  HashElem *k;
+  int iStatCur;
+  int iMem;
+
+  sqlite3BeginWriteOperation(pParse, 0, iDb);
+  iStatCur = pParse->nTab;
+  pParse->nTab += 2;
+  openStatTable(pParse, iDb, iStatCur, 0);
+  iMem = pParse->nMem+1;
+  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
+    Table *pTab = (Table*)sqliteHashData(k);
+    analyzeOneTable(pParse, pTab, iStatCur, iMem);
   }
-  sqlite3CreateFunc(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "glob", 2, SQLITE_UTF8, 
-      (struct compareInfo*)&globInfo, likeFunc, 0,0);
-  setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE);
-  setLikeOptFlag(db, "like", 
-      caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE);
+  loadAnalysis(pParse, iDb);
 }
 
 /*
-** pExpr points to an expression which implements a function.  If
-** it is appropriate to apply the LIKE optimization to that function
-** then set aWc[0] through aWc[2] to the wildcard characters and
-** return TRUE.  If the function is not a LIKE-style function then
-** return FALSE.
+** Generate code that will do an analysis of a single table in
+** a database.
 */
-SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
-  FuncDef *pDef;
-  if( pExpr->op!=TK_FUNCTION || !pExpr->pList ){
-    return 0;
-  }
-  if( pExpr->pList->nExpr!=2 ){
-    return 0;
-  }
-  pDef = sqlite3FindFunction(db, (char*)pExpr->token.z, pExpr->token.n, 2,
-                             SQLITE_UTF8, 0);
-  if( pDef==0 || (pDef->flags & SQLITE_FUNC_LIKE)==0 ){
-    return 0;
-  }
+static void analyzeTable(Parse *pParse, Table *pTab){
+  int iDb;
+  int iStatCur;
 
-  /* The memcpy() statement assumes that the wildcard characters are
-  ** the first three statements in the compareInfo structure.  The
-  ** asserts() that follow verify that assumption
-  */
-  memcpy(aWc, pDef->pUserData, 3);
-  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
-  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
-  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );
-  *pIsNocase = (pDef->flags & SQLITE_FUNC_CASE)==0;
-  return 1;
+  assert( pTab!=0 );
+  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
+  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+  sqlite3BeginWriteOperation(pParse, 0, iDb);
+  iStatCur = pParse->nTab;
+  pParse->nTab += 2;
+  openStatTable(pParse, iDb, iStatCur, pTab->zName);
+  analyzeOneTable(pParse, pTab, iStatCur, pParse->nMem+1);
+  loadAnalysis(pParse, iDb);
 }
 
-/************** End of func.c ************************************************/
-/************** Begin file insert.c ******************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Generate code for the ANALYZE command.  The parser calls this routine
+** when it recognizes an ANALYZE command.
 **
-*************************************************************************
-** This file contains C code routines that are called by the parser
-** to handle INSERT statements in SQLite.
+**        ANALYZE                            -- 1
+**        ANALYZE  <database>                -- 2
+**        ANALYZE  ?<database>.?<tablename>  -- 3
 **
-** $Id: insert.c,v 1.238 2008/04/28 18:46:43 drh Exp $
+** Form 1 causes all indices in all attached databases to be analyzed.
+** Form 2 analyzes all indices the single database named.
+** Form 3 analyzes all indices associated with the named table.
 */
+SQLITE_PRIVATE void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
+  sqlite3 *db = pParse->db;
+  int iDb;
+  int i;
+  char *z, *zDb;
+  Table *pTab;
+  Token *pTableName;
 
-/*
-** Set P4 of the most recently inserted opcode to a column affinity
-** string for index pIdx. A column affinity string has one character
-** for each column in the table, according to the affinity of the column:
-**
-**  Character      Column affinity
-**  ------------------------------
-**  'a'            TEXT
-**  'b'            NONE
-**  'c'            NUMERIC
-**  'd'            INTEGER
-**  'e'            REAL
-**
-** An extra 'b' is appended to the end of the string to cover the
-** rowid that appears as the last column in every index.
-*/
-SQLITE_PRIVATE void sqlite3IndexAffinityStr(Vdbe *v, Index *pIdx){
-  if( !pIdx->zColAff ){
-    /* The first time a column affinity string for a particular index is
-    ** required, it is allocated and populated here. It is then stored as
-    ** a member of the Index structure for subsequent use.
-    **
-    ** The column affinity string will eventually be deleted by
-    ** sqliteDeleteIndex() when the Index structure itself is cleaned
-    ** up.
-    */
-    int n;
-    Table *pTab = pIdx->pTable;
-    sqlite3 *db = sqlite3VdbeDb(v);
-    pIdx->zColAff = (char *)sqlite3DbMallocRaw(db, pIdx->nColumn+2);
-    if( !pIdx->zColAff ){
-      return;
+  /* Read the database schema. If an error occurs, leave an error message
+  ** and code in pParse and return NULL. */
+  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    return;
+  }
+
+  assert( pName2!=0 || pName1==0 );
+  if( pName1==0 ){
+    /* Form 1:  Analyze everything */
+    for(i=0; i<db->nDb; i++){
+      if( i==1 ) continue;  /* Do not analyze the TEMP database */
+      analyzeDatabase(pParse, i);
     }
-    for(n=0; n<pIdx->nColumn; n++){
-      pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity;
+  }else if( pName2->n==0 ){
+    /* Form 2:  Analyze the database or table named */
+    iDb = sqlite3FindDb(db, pName1);
+    if( iDb>=0 ){
+      analyzeDatabase(pParse, iDb);
+    }else{
+      z = sqlite3NameFromToken(db, pName1);
+      if( z ){
+        pTab = sqlite3LocateTable(pParse, 0, z, 0);
+        sqlite3DbFree(db, z);
+        if( pTab ){
+          analyzeTable(pParse, pTab);
+        }
+      }
     }
-    pIdx->zColAff[n++] = SQLITE_AFF_NONE;
-    pIdx->zColAff[n] = 0;
+  }else{
+    /* Form 3: Analyze the fully qualified table name */
+    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pTableName);
+    if( iDb>=0 ){
+      zDb = db->aDb[iDb].zName;
+      z = sqlite3NameFromToken(db, pTableName);
+      if( z ){
+        pTab = sqlite3LocateTable(pParse, 0, z, zDb);
+        sqlite3DbFree(db, z);
+        if( pTab ){
+          analyzeTable(pParse, pTab);
+        }
+      }
+    }   
   }
- 
-  sqlite3VdbeChangeP4(v, -1, pIdx->zColAff, 0);
 }
 
 /*
-** Set P4 of the most recently inserted opcode to a column affinity
-** string for table pTab. A column affinity string has one character
-** for each column indexed by the index, according to the affinity of the
-** column:
+** Used to pass information from the analyzer reader through to the
+** callback routine.
+*/
+typedef struct analysisInfo analysisInfo;
+struct analysisInfo {
+  sqlite3 *db;
+  const char *zDatabase;
+};
+
+/*
+** This callback is invoked once for each index when reading the
+** sqlite_stat1 table.  
 **
-**  Character      Column affinity
-**  ------------------------------
-**  'a'            TEXT
-**  'b'            NONE
-**  'c'            NUMERIC
-**  'd'            INTEGER
-**  'e'            REAL
+**     argv[0] = name of the index
+**     argv[1] = results of analysis - on integer for each column
 */
-SQLITE_PRIVATE void sqlite3TableAffinityStr(Vdbe *v, Table *pTab){
-  /* The first time a column affinity string for a particular table
-  ** is required, it is allocated and populated here. It is then 
-  ** stored as a member of the Table structure for subsequent use.
-  **
-  ** The column affinity string will eventually be deleted by
-  ** sqlite3DeleteTable() when the Table structure itself is cleaned up.
-  */
-  if( !pTab->zColAff ){
-    char *zColAff;
-    int i;
-    sqlite3 *db = sqlite3VdbeDb(v);
+static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
+  analysisInfo *pInfo = (analysisInfo*)pData;
+  Index *pIndex;
+  int i, c;
+  unsigned int v;
+  const char *z;
 
-    zColAff = (char *)sqlite3DbMallocRaw(db, pTab->nCol+1);
-    if( !zColAff ){
-      return;
-    }
+  assert( argc==2 );
+  UNUSED_PARAMETER2(NotUsed, argc);
 
-    for(i=0; i<pTab->nCol; i++){
-      zColAff[i] = pTab->aCol[i].affinity;
+  if( argv==0 || argv[0]==0 || argv[1]==0 ){
+    return 0;
+  }
+  pIndex = sqlite3FindIndex(pInfo->db, argv[0], pInfo->zDatabase);
+  if( pIndex==0 ){
+    return 0;
+  }
+  z = argv[1];
+  for(i=0; *z && i<=pIndex->nColumn; i++){
+    v = 0;
+    while( (c=z[0])>='0' && c<='9' ){
+      v = v*10 + c - '0';
+      z++;
     }
-    zColAff[pTab->nCol] = '\0';
-
-    pTab->zColAff = zColAff;
+    pIndex->aiRowEst[i] = v;
+    if( *z==' ' ) z++;
   }
-
-  sqlite3VdbeChangeP4(v, -1, pTab->zColAff, 0);
+  return 0;
 }
 
 /*
-** Return non-zero if the table pTab in database iDb or any of its indices
-** have been opened at any point in the VDBE program beginning at location
-** iStartAddr throught the end of the program.  This is used to see if 
-** a statement of the form  "INSERT INTO <iDb, pTab> SELECT ..." can 
-** run without using temporary table for the results of the SELECT. 
+** If the Index.aSample variable is not NULL, delete the aSample[] array
+** and its contents.
 */
-static int readsTable(Vdbe *v, int iStartAddr, int iDb, Table *pTab){
-  int i;
-  int iEnd = sqlite3VdbeCurrentAddr(v);
-  for(i=iStartAddr; i<iEnd; i++){
-    VdbeOp *pOp = sqlite3VdbeGetOp(v, i);
-    assert( pOp!=0 );
-    if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){
-      Index *pIndex;
-      int tnum = pOp->p2;
-      if( tnum==pTab->tnum ){
-        return 1;
-      }
-      for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
-        if( tnum==pIndex->tnum ){
-          return 1;
-        }
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index *pIdx){
+#ifdef SQLITE_ENABLE_STAT2
+  if( pIdx->aSample ){
+    int j;
+    sqlite3 *dbMem = pIdx->pTable->dbMem;
+    for(j=0; j<SQLITE_INDEX_SAMPLES; j++){
+      IndexSample *p = &pIdx->aSample[j];
+      if( p->eType==SQLITE_TEXT || p->eType==SQLITE_BLOB ){
+        sqlite3DbFree(pIdx->pTable->dbMem, p->u.z);
       }
     }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pTab->pVtab ){
-      assert( pOp->p4.pVtab!=0 );
-      assert( pOp->p4type==P4_VTAB );
-      return 1;
-    }
-#endif
+    sqlite3DbFree(dbMem, pIdx->aSample);
+    pIdx->aSample = 0;
   }
-  return 0;
+#else
+  UNUSED_PARAMETER(pIdx);
+#endif
 }
 
-#ifndef SQLITE_OMIT_AUTOINCREMENT
 /*
-** Write out code to initialize the autoincrement logic.  This code
-** looks up the current autoincrement value in the sqlite_sequence
-** table and stores that value in a register.  Code generated by
-** autoIncStep() will keep that register holding the largest
-** rowid value.  Code generated by autoIncEnd() will write the new
-** largest value of the counter back into the sqlite_sequence table.
+** Load the content of the sqlite_stat1 and sqlite_stat2 tables. The
+** contents of sqlite_stat1 are used to populate the Index.aiRowEst[]
+** arrays. The contents of sqlite_stat2 are used to populate the
+** Index.aSample[] arrays.
+**
+** If the sqlite_stat1 table is not present in the database, SQLITE_ERROR
+** is returned. In this case, even if SQLITE_ENABLE_STAT2 was defined 
+** during compilation and the sqlite_stat2 table is present, no data is 
+** read from it.
 **
-** This routine returns the index of the mem[] cell that contains
-** the maximum rowid counter.
+** If SQLITE_ENABLE_STAT2 was defined during compilation and the 
+** sqlite_stat2 table is not present in the database, SQLITE_ERROR is
+** returned. However, in this case, data is read from the sqlite_stat1
+** table (if it is present) before returning.
 **
-** Three consecutive registers are allocated by this routine.  The
-** first two hold the name of the target table and the maximum rowid 
-** inserted into the target table, respectively.
-** The third holds the rowid in sqlite_sequence where we will
-** write back the revised maximum rowid.  This routine returns the
-** index of the second of these three registers.
+** If an OOM error occurs, this function always sets db->mallocFailed.
+** This means if the caller does not care about other errors, the return
+** code may be ignored.
 */
-static int autoIncBegin(
-  Parse *pParse,      /* Parsing context */
-  int iDb,            /* Index of the database holding pTab */
-  Table *pTab         /* The table we are writing to */
-){
-  int memId = 0;      /* Register holding maximum rowid */
-  if( pTab->autoInc ){
-    Vdbe *v = pParse->pVdbe;
-    Db *pDb = &pParse->db->aDb[iDb];
-    int iCur = pParse->nTab;
-    int addr;               /* Address of the top of the loop */
-    assert( v );
-    pParse->nMem++;         /* Holds name of table */
-    memId = ++pParse->nMem;
-    pParse->nMem++;
-    sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
-    addr = sqlite3VdbeCurrentAddr(v);
-    sqlite3VdbeAddOp4(v, OP_String8, 0, memId-1, 0, pTab->zName, 0);
-    sqlite3VdbeAddOp2(v, OP_Rewind, iCur, addr+8);
-    sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, memId);
-    sqlite3VdbeAddOp3(v, OP_Ne, memId-1, addr+7, memId);
-    sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
-    sqlite3VdbeAddOp2(v, OP_Rowid, iCur, memId+1);
-    sqlite3VdbeAddOp3(v, OP_Column, iCur, 1, memId);
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+8);
-    sqlite3VdbeAddOp2(v, OP_Next, iCur, addr+2);
-    sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
+SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
+  analysisInfo sInfo;
+  HashElem *i;
+  char *zSql;
+  int rc;
+
+  assert( iDb>=0 && iDb<db->nDb );
+  assert( db->aDb[iDb].pBt!=0 );
+  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
+
+  /* Clear any prior statistics */
+  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
+    Index *pIdx = sqliteHashData(i);
+    sqlite3DefaultRowEst(pIdx);
+    sqlite3DeleteIndexSamples(pIdx);
   }
-  return memId;
-}
 
-/*
-** Update the maximum rowid for an autoincrement calculation.
-**
-** This routine should be called when the top of the stack holds a
-** new rowid that is about to be inserted.  If that new rowid is
-** larger than the maximum rowid in the memId memory cell, then the
-** memory cell is updated.  The stack is unchanged.
-*/
-static void autoIncStep(Parse *pParse, int memId, int regRowid){
-  if( memId>0 ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid);
+  /* Check to make sure the sqlite_stat1 table exists */
+  sInfo.db = db;
+  sInfo.zDatabase = db->aDb[iDb].zName;
+  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
+    return SQLITE_ERROR;
   }
-}
 
-/*
-** After doing one or more inserts, the maximum rowid is stored
-** in reg[memId].  Generate code to write this value back into the
-** the sqlite_sequence table.
-*/
-static void autoIncEnd(
-  Parse *pParse,     /* The parsing context */
-  int iDb,           /* Index of the database holding pTab */
-  Table *pTab,       /* Table we are inserting into */
-  int memId          /* Memory cell holding the maximum rowid */
-){
-  if( pTab->autoInc ){
-    int iCur = pParse->nTab;
-    Vdbe *v = pParse->pVdbe;
-    Db *pDb = &pParse->db->aDb[iDb];
-    int j1;
-    int iRec = ++pParse->nMem;    /* Memory cell used for record */
+  /* Load new statistics out of the sqlite_stat1 table */
+  zSql = sqlite3MPrintf(db, 
+      "SELECT idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
+  if( zSql==0 ){
+    rc = SQLITE_NOMEM;
+  }else{
+    (void)sqlite3SafetyOff(db);
+    rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
+    (void)sqlite3SafetyOn(db);
+    sqlite3DbFree(db, zSql);
+  }
 
-    assert( v );
-    sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
-    j1 = sqlite3VdbeAddOp1(v, OP_NotNull, memId+1);
-    sqlite3VdbeAddOp2(v, OP_NewRowid, iCur, memId+1);
-    sqlite3VdbeJumpHere(v, j1);
-    sqlite3VdbeAddOp3(v, OP_MakeRecord, memId-1, 2, iRec);
-    sqlite3VdbeAddOp3(v, OP_Insert, iCur, iRec, memId+1);
-    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
-    sqlite3VdbeAddOp1(v, OP_Close, iCur);
+
+  /* Load the statistics from the sqlite_stat2 table. */
+#ifdef SQLITE_ENABLE_STAT2
+  if( rc==SQLITE_OK && !sqlite3FindTable(db, "sqlite_stat2", sInfo.zDatabase) ){
+    rc = SQLITE_ERROR;
+  }
+  if( rc==SQLITE_OK ){
+    sqlite3_stmt *pStmt = 0;
+
+    zSql = sqlite3MPrintf(db, 
+        "SELECT idx,sampleno,sample FROM %Q.sqlite_stat2", sInfo.zDatabase);
+    if( !zSql ){
+      rc = SQLITE_NOMEM;
+    }else{
+      (void)sqlite3SafetyOff(db);
+      rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
+      (void)sqlite3SafetyOn(db);
+      sqlite3DbFree(db, zSql);
+    }
+
+    if( rc==SQLITE_OK ){
+      (void)sqlite3SafetyOff(db);
+      while( sqlite3_step(pStmt)==SQLITE_ROW ){
+        char *zIndex = (char *)sqlite3_column_text(pStmt, 0);
+        Index *pIdx = sqlite3FindIndex(db, zIndex, sInfo.zDatabase);
+        if( pIdx ){
+          int iSample = sqlite3_column_int(pStmt, 1);
+          sqlite3 *dbMem = pIdx->pTable->dbMem;
+          assert( dbMem==db || dbMem==0 );
+          if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
+            int eType = sqlite3_column_type(pStmt, 2);
+
+            if( pIdx->aSample==0 ){
+              static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
+              pIdx->aSample = (IndexSample *)sqlite3DbMallocZero(dbMem, sz);
+              if( pIdx->aSample==0 ){
+                db->mallocFailed = 1;
+                break;
+              }
+            }
+
+            assert( pIdx->aSample );
+            {
+              IndexSample *pSample = &pIdx->aSample[iSample];
+              pSample->eType = (u8)eType;
+              if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
+                pSample->u.r = sqlite3_column_double(pStmt, 2);
+              }else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
+                const char *z = (const char *)(
+                    (eType==SQLITE_BLOB) ?
+                    sqlite3_column_blob(pStmt, 2):
+                    sqlite3_column_text(pStmt, 2)
+                );
+                int n = sqlite3_column_bytes(pStmt, 2);
+                if( n>24 ){
+                  n = 24;
+                }
+                pSample->nByte = (u8)n;
+                pSample->u.z = sqlite3DbMallocRaw(dbMem, n);
+                if( pSample->u.z ){
+                  memcpy(pSample->u.z, z, n);
+                }else{
+                  db->mallocFailed = 1;
+                  break;
+                }
+              }
+            }
+          }
+        }
+      }
+      rc = sqlite3_finalize(pStmt);
+      (void)sqlite3SafetyOn(db);
+    }
+  }
+#endif
+
+  if( rc==SQLITE_NOMEM ){
+    db->mallocFailed = 1;
   }
+  return rc;
 }
-#else
-/*
-** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines
-** above are all no-ops
-*/
-# define autoIncBegin(A,B,C) (0)
-# define autoIncStep(A,B,C)
-# define autoIncEnd(A,B,C,D)
-#endif /* SQLITE_OMIT_AUTOINCREMENT */
 
 
-/* Forward declaration */
-static int xferOptimization(
-  Parse *pParse,        /* Parser context */
-  Table *pDest,         /* The table we are inserting into */
-  Select *pSelect,      /* A SELECT statement to use as the data source */
-  int onError,          /* How to handle constraint errors */
-  int iDbDest           /* The database of pDest */
-);
+#endif /* SQLITE_OMIT_ANALYZE */
 
+/************** End of analyze.c *********************************************/
+/************** Begin file attach.c ******************************************/
 /*
-** This routine is call to handle SQL of the following forms:
+** 2003 April 6
 **
-**    insert into TABLE (IDLIST) values(EXPRLIST)
-**    insert into TABLE (IDLIST) select
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** The IDLIST following the table name is always optional.  If omitted,
-** then a list of all columns for the table is substituted.  The IDLIST
-** appears in the pColumn parameter.  pColumn is NULL if IDLIST is omitted.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** The pList parameter holds EXPRLIST in the first form of the INSERT
-** statement above, and pSelect is NULL.  For the second form, pList is
-** NULL and pSelect is a pointer to the select statement used to generate
-** data for the insert.
+*************************************************************************
+** This file contains code used to implement the ATTACH and DETACH commands.
 **
-** The code generated follows one of four templates.  For a simple
-** select with data coming from a VALUES clause, the code executes
-** once straight down through.  The template looks like this:
+** $Id: attach.c,v 1.93 2009/05/31 21:21:41 drh Exp $
+*/
+
+#ifndef SQLITE_OMIT_ATTACH
+/*
+** Resolve an expression that was part of an ATTACH or DETACH statement. This
+** is slightly different from resolving a normal SQL expression, because simple
+** identifiers are treated as strings, not possible column names or aliases.
 **
-**         open write cursor to <table> and its indices
-**         puts VALUES clause expressions onto the stack
-**         write the resulting record into <table>
-**         cleanup
+** i.e. if the parser sees:
 **
-** The three remaining templates assume the statement is of the form
+**     ATTACH DATABASE abc AS def
 **
-**   INSERT INTO <table> SELECT ...
+** it treats the two expressions as literal strings 'abc' and 'def' instead of
+** looking for columns of the same name.
 **
-** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" -
-** in other words if the SELECT pulls all columns from a single table
-** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and
-** if <table2> and <table1> are distinct tables but have identical
-** schemas, including all the same indices, then a special optimization
-** is invoked that copies raw records from <table2> over to <table1>.
-** See the xferOptimization() function for the implementation of this
-** template.  This is the second template.
+** This only applies to the root node of pExpr, so the statement:
 **
-**         open a write cursor to <table>
-**         open read cursor on <table2>
-**         transfer all records in <table2> over to <table>
-**         close cursors
-**         foreach index on <table>
-**           open a write cursor on the <table> index
-**           open a read cursor on the corresponding <table2> index
-**           transfer all records from the read to the write cursors
-**           close cursors
-**         end foreach
+**     ATTACH DATABASE abc||def AS 'db2'
 **
-** The third template is for when the second template does not apply
-** and the SELECT clause does not read from <table> at any time.
-** The generated code follows this template:
+** will fail because neither abc or def can be resolved.
+*/
+static int resolveAttachExpr(NameContext *pName, Expr *pExpr)
+{
+  int rc = SQLITE_OK;
+  if( pExpr ){
+    if( pExpr->op!=TK_ID ){
+      rc = sqlite3ResolveExprNames(pName, pExpr);
+      if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){
+        sqlite3ErrorMsg(pName->pParse, "invalid name: \"%s\"", pExpr->u.zToken);
+        return SQLITE_ERROR;
+      }
+    }else{
+      pExpr->op = TK_STRING;
+    }
+  }
+  return rc;
+}
+
+/*
+** An SQL user-function registered to do the work of an ATTACH statement. The
+** three arguments to the function come directly from an attach statement:
 **
-**         goto B
-**      A: setup for the SELECT
-**         loop over the rows in the SELECT
-**           gosub C
-**         end loop
-**         cleanup after the SELECT
-**         goto D
-**      B: open write cursor to <table> and its indices
-**         goto A
-**      C: insert the select result into <table>
-**         return
-**      D: cleanup
+**     ATTACH DATABASE x AS y KEY z
 **
-** The fourth template is used if the insert statement takes its
-** values from a SELECT but the data is being inserted into a table
-** that is also read as part of the SELECT.  In the third form,
-** we have to use a intermediate table to store the results of
-** the select.  The template is like this:
+**     SELECT sqlite_attach(x, y, z)
 **
-**         goto B
-**      A: setup for the SELECT
-**         loop over the tables in the SELECT
-**           gosub C
-**         end loop
-**         cleanup after the SELECT
-**         goto D
-**      C: insert the select result into the intermediate table
-**         return
-**      B: open a cursor to an intermediate table
-**         goto A
-**      D: open write cursor to <table> and its indices
-**         loop over the intermediate table
-**           transfer values form intermediate table into <table>
-**         end the loop
-**         cleanup
+** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
+** third argument.
 */
-SQLITE_PRIVATE void sqlite3Insert(
-  Parse *pParse,        /* Parser context */
-  SrcList *pTabList,    /* Name of table into which we are inserting */
-  ExprList *pList,      /* List of values to be inserted */
-  Select *pSelect,      /* A SELECT statement to use as the data source */
-  IdList *pColumn,      /* Column names corresponding to IDLIST. */
-  int onError           /* How to handle constraint errors */
+static void attachFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **argv
 ){
-  sqlite3 *db;          /* The main database structure */
-  Table *pTab;          /* The table to insert into.  aka TABLE */
-  char *zTab;           /* Name of the table into which we are inserting */
-  const char *zDb;      /* Name of the database holding this table */
-  int i, j, idx;        /* Loop counters */
-  Vdbe *v;              /* Generate code into this virtual machine */
-  Index *pIdx;          /* For looping over indices of the table */
-  int nColumn;          /* Number of columns in the data */
-  int nHidden = 0;      /* Number of hidden columns if TABLE is virtual */
-  int baseCur = 0;      /* VDBE Cursor number for pTab */
-  int keyColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
-  int endOfLoop;        /* Label for the end of the insertion loop */
-  int useTempTable = 0; /* Store SELECT results in intermediate table */
-  int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
-  int iCont=0,iBreak=0; /* Beginning and end of the loop over srcTab */
-  int iSelectLoop = 0;  /* Address of code that implements the SELECT */
-  int iCleanup = 0;     /* Address of the cleanup code */
-  int iInsertBlock = 0; /* Address of the subroutine used to insert data */
-  int newIdx = -1;      /* Cursor for the NEW pseudo-table */
-  int iDb;              /* Index of database holding TABLE */
-  Db *pDb;              /* The database containing table being inserted into */
-  int appendFlag = 0;   /* True if the insert is likely to be an append */
-
-  /* Register allocations */
-  int regFromSelect;    /* Base register for data coming from SELECT */
-  int regAutoinc = 0;   /* Register holding the AUTOINCREMENT counter */
-  int regRowCount = 0;  /* Memory cell used for the row counter */
-  int regIns;           /* Block of regs holding rowid+data being inserted */
-  int regRowid;         /* registers holding insert rowid */
-  int regData;          /* register holding first column to insert */
-  int regRecord;        /* Holds the assemblied row record */
-  int *aRegIdx = 0;     /* One register allocated to each index */
-
+  int i;
+  int rc = 0;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  const char *zName;
+  const char *zFile;
+  Db *aNew;
+  char *zErrDyn = 0;
 
-#ifndef SQLITE_OMIT_TRIGGER
-  int isView;                 /* True if attempting to insert into a view */
-  int triggers_exist = 0;     /* True if there are FOR EACH ROW triggers */
-#endif
+  UNUSED_PARAMETER(NotUsed);
 
-  db = pParse->db;
-  if( pParse->nErr || db->mallocFailed ){
-    goto insert_cleanup;
-  }
+  zFile = (const char *)sqlite3_value_text(argv[0]);
+  zName = (const char *)sqlite3_value_text(argv[1]);
+  if( zFile==0 ) zFile = "";
+  if( zName==0 ) zName = "";
 
-  /* Locate the table into which we will be inserting new information.
+  /* Check for the following errors:
+  **
+  **     * Too many attached databases,
+  **     * Transaction currently open
+  **     * Specified database name already being used.
   */
-  assert( pTabList->nSrc==1 );
-  zTab = pTabList->a[0].zName;
-  if( zTab==0 ) goto insert_cleanup;
-  pTab = sqlite3SrcListLookup(pParse, pTabList);
-  if( pTab==0 ){
-    goto insert_cleanup;
+  if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){
+    zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d", 
+      db->aLimit[SQLITE_LIMIT_ATTACHED]
+    );
+    goto attach_error;
   }
-  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-  assert( iDb<db->nDb );
-  pDb = &db->aDb[iDb];
-  zDb = pDb->zName;
-  if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
-    goto insert_cleanup;
+  if( !db->autoCommit ){
+    zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction");
+    goto attach_error;
+  }
+  for(i=0; i<db->nDb; i++){
+    char *z = db->aDb[i].zName;
+    assert( z && zName );
+    if( sqlite3StrICmp(z, zName)==0 ){
+      zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName);
+      goto attach_error;
+    }
   }
 
-  /* Figure out if we have any triggers and if the table being
-  ** inserted into is a view
-  */
-#ifndef SQLITE_OMIT_TRIGGER
-  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0);
-  isView = pTab->pSelect!=0;
-#else
-# define triggers_exist 0
-# define isView 0
-#endif
-#ifdef SQLITE_OMIT_VIEW
-# undef isView
-# define isView 0
-#endif
-
-  /* Ensure that:
-  *  (a) the table is not read-only, 
-  *  (b) that if it is a view then ON INSERT triggers exist
+  /* Allocate the new entry in the db->aDb[] array and initialise the schema
+  ** hash tables.
   */
-  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
-    goto insert_cleanup;
+  if( db->aDb==db->aDbStatic ){
+    aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 );
+    if( aNew==0 ) return;
+    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
+  }else{
+    aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
+    if( aNew==0 ) return;
   }
-  assert( pTab!=0 );
+  db->aDb = aNew;
+  aNew = &db->aDb[db->nDb];
+  memset(aNew, 0, sizeof(*aNew));
 
-  /* If pTab is really a view, make sure it has been initialized.
-  ** ViewGetColumnNames() is a no-op if pTab is not a view (or virtual 
-  ** module table).
+  /* Open the database file. If the btree is successfully opened, use
+  ** it to obtain the database schema. At this point the schema may
+  ** or may not be initialised.
   */
-  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-    goto insert_cleanup;
+  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE,
+                           db->openFlags | SQLITE_OPEN_MAIN_DB,
+                           &aNew->pBt);
+  db->nDb++;
+  if( rc==SQLITE_CONSTRAINT ){
+    rc = SQLITE_ERROR;
+    zErrDyn = sqlite3MPrintf(db, "database is already attached");
+  }else if( rc==SQLITE_OK ){
+    Pager *pPager;
+    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
+    if( !aNew->pSchema ){
+      rc = SQLITE_NOMEM;
+    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
+      zErrDyn = sqlite3MPrintf(db, 
+        "attached databases must use the same text encoding as main database");
+      rc = SQLITE_ERROR;
+    }
+    pPager = sqlite3BtreePager(aNew->pBt);
+    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
+    sqlite3PagerJournalMode(pPager, db->dfltJournalMode);
   }
+  aNew->zName = sqlite3DbStrDup(db, zName);
+  aNew->safety_level = 3;
 
-  /* Allocate a VDBE
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ) goto insert_cleanup;
-  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
-  sqlite3BeginWriteOperation(pParse, pSelect || triggers_exist, iDb);
+#if SQLITE_HAS_CODEC
+  {
+    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
+    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
+    int nKey;
+    char *zKey;
+    int t = sqlite3_value_type(argv[2]);
+    switch( t ){
+      case SQLITE_INTEGER:
+      case SQLITE_FLOAT:
+        zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
+        rc = SQLITE_ERROR;
+        break;
+        
+      case SQLITE_TEXT:
+      case SQLITE_BLOB:
+        nKey = sqlite3_value_bytes(argv[2]);
+        zKey = (char *)sqlite3_value_blob(argv[2]);
+        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
+        break;
 
-  /* if there are row triggers, allocate a temp table for new.* references. */
-  if( triggers_exist ){
-    newIdx = pParse->nTab++;
+      case SQLITE_NULL:
+        /* No key specified.  Use the key from the main database */
+        sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
+        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
+        break;
+    }
   }
+#endif
 
-#ifndef SQLITE_OMIT_XFER_OPT
-  /* If the statement is of the form
-  **
-  **       INSERT INTO <table1> SELECT * FROM <table2>;
-  **
-  ** Then special optimizations can be applied that make the transfer
-  ** very fast and which reduce fragmentation of indices.
+  /* If the file was opened successfully, read the schema for the new database.
+  ** If this fails, or if opening the file failed, then close the file and 
+  ** remove the entry from the db->aDb[] array. i.e. put everything back the way
+  ** we found it.
   */
-  if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
-    assert( !triggers_exist );
-    assert( pList==0 );
-    goto insert_cleanup;
+  if( rc==SQLITE_OK ){
+    (void)sqlite3SafetyOn(db);
+    sqlite3BtreeEnterAll(db);
+    rc = sqlite3Init(db, &zErrDyn);
+    sqlite3BtreeLeaveAll(db);
+    (void)sqlite3SafetyOff(db);
   }
-#endif /* SQLITE_OMIT_XFER_OPT */
-
-  /* If this is an AUTOINCREMENT table, look up the sequence number in the
-  ** sqlite_sequence table and store it in memory cell regAutoinc.
-  */
-  regAutoinc = autoIncBegin(pParse, iDb, pTab);
-
-  /* Figure out how many columns of data are supplied.  If the data
-  ** is coming from a SELECT statement, then this step also generates
-  ** all the code to implement the SELECT statement and invoke a subroutine
-  ** to process each row of the result. (Template 2.) If the SELECT
-  ** statement uses the the table that is being inserted into, then the
-  ** subroutine is also coded here.  That subroutine stores the SELECT
-  ** results in a temporary table. (Template 3.)
-  */
-  if( pSelect ){
-    /* Data is coming from a SELECT.  Generate code to implement that SELECT
-    */
-    SelectDest dest;
-    int rc, iInitCode;
-
-    iInitCode = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    iSelectLoop = sqlite3VdbeCurrentAddr(v);
-    iInsertBlock = sqlite3VdbeMakeLabel(v);
-    sqlite3SelectDestInit(&dest, SRT_Subroutine, iInsertBlock);
-
-    /* Resolve the expressions in the SELECT statement and execute it. */
-    rc = sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
-    if( rc || pParse->nErr || db->mallocFailed ){
-      goto insert_cleanup;
+  if( rc ){
+    int iDb = db->nDb - 1;
+    assert( iDb>=2 );
+    if( db->aDb[iDb].pBt ){
+      sqlite3BtreeClose(db->aDb[iDb].pBt);
+      db->aDb[iDb].pBt = 0;
+      db->aDb[iDb].pSchema = 0;
     }
-
-    regFromSelect = dest.iMem;
-    iCleanup = sqlite3VdbeMakeLabel(v);
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iCleanup);
-    assert( pSelect->pEList );
-    nColumn = pSelect->pEList->nExpr;
-
-    /* Set useTempTable to TRUE if the result of the SELECT statement
-    ** should be written into a temporary table.  Set to FALSE if each
-    ** row of the SELECT can be written directly into the result table.
-    **
-    ** A temp table must be used if the table being updated is also one
-    ** of the tables being read by the SELECT statement.  Also use a 
-    ** temp table in the case of row triggers.
-    */
-    if( triggers_exist || readsTable(v, iSelectLoop, iDb, pTab) ){
-      useTempTable = 1;
+    sqlite3ResetInternalSchema(db, 0);
+    db->nDb = iDb;
+    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
+      db->mallocFailed = 1;
+      sqlite3DbFree(db, zErrDyn);
+      zErrDyn = sqlite3MPrintf(db, "out of memory");
+    }else if( zErrDyn==0 ){
+      zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile);
     }
+    goto attach_error;
+  }
+  
+  return;
 
-    if( useTempTable ){
-      /* Generate the subroutine that SELECT calls to process each row of
-      ** the result.  Store the result in a temporary table
-      */
-      int regRec, regRowid;
+attach_error:
+  /* Return an error if we get here */
+  if( zErrDyn ){
+    sqlite3_result_error(context, zErrDyn, -1);
+    sqlite3DbFree(db, zErrDyn);
+  }
+  if( rc ) sqlite3_result_error_code(context, rc);
+}
 
-      srcTab = pParse->nTab++;
-      regRec = sqlite3GetTempReg(pParse);
-      regRowid = sqlite3GetTempReg(pParse);
-      sqlite3VdbeResolveLabel(v, iInsertBlock);
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
-      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regRowid);
-      sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regRowid);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      sqlite3ReleaseTempReg(pParse, regRec);
-      sqlite3ReleaseTempReg(pParse, regRowid);
+/*
+** An SQL user-function registered to do the work of an DETACH statement. The
+** three arguments to the function come directly from a detach statement:
+**
+**     DETACH DATABASE x
+**
+**     SELECT sqlite_detach(x)
+*/
+static void detachFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **argv
+){
+  const char *zName = (const char *)sqlite3_value_text(argv[0]);
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  int i;
+  Db *pDb = 0;
+  char zErr[128];
 
-      /* The following code runs first because the GOTO at the very top
-      ** of the program jumps to it.  Create the temporary table, then jump
-      ** back up and execute the SELECT code above.
-      */
-      sqlite3VdbeJumpHere(v, iInitCode);
-      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, iSelectLoop);
-      sqlite3VdbeResolveLabel(v, iCleanup);
-    }else{
-      sqlite3VdbeJumpHere(v, iInitCode);
-    }
-  }else{
-    /* This is the case if the data for the INSERT is coming from a VALUES
-    ** clause
-    */
-    NameContext sNC;
-    memset(&sNC, 0, sizeof(sNC));
-    sNC.pParse = pParse;
-    srcTab = -1;
-    assert( useTempTable==0 );
-    nColumn = pList ? pList->nExpr : 0;
-    for(i=0; i<nColumn; i++){
-      if( sqlite3ExprResolveNames(&sNC, pList->a[i].pExpr) ){
-        goto insert_cleanup;
-      }
-    }
+  UNUSED_PARAMETER(NotUsed);
+
+  if( zName==0 ) zName = "";
+  for(i=0; i<db->nDb; i++){
+    pDb = &db->aDb[i];
+    if( pDb->pBt==0 ) continue;
+    if( sqlite3StrICmp(pDb->zName, zName)==0 ) break;
   }
 
-  /* Make sure the number of columns in the source data matches the number
-  ** of columns to be inserted into the table.
-  */
-  if( IsVirtual(pTab) ){
-    for(i=0; i<pTab->nCol; i++){
-      nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0);
-    }
+  if( i>=db->nDb ){
+    sqlite3_snprintf(sizeof(zErr),zErr, "no such database: %s", zName);
+    goto detach_error;
   }
-  if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
-    sqlite3ErrorMsg(pParse, 
-       "table %S has %d columns but %d values were supplied",
-       pTabList, 0, pTab->nCol, nColumn);
-    goto insert_cleanup;
+  if( i<2 ){
+    sqlite3_snprintf(sizeof(zErr),zErr, "cannot detach database %s", zName);
+    goto detach_error;
   }
-  if( pColumn!=0 && nColumn!=pColumn->nId ){
-    sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
-    goto insert_cleanup;
+  if( !db->autoCommit ){
+    sqlite3_snprintf(sizeof(zErr), zErr,
+                     "cannot DETACH database within transaction");
+    goto detach_error;
   }
-
-  /* If the INSERT statement included an IDLIST term, then make sure
-  ** all elements of the IDLIST really are columns of the table and 
-  ** remember the column indices.
-  **
-  ** If the table has an INTEGER PRIMARY KEY column and that column
-  ** is named in the IDLIST, then record in the keyColumn variable
-  ** the index into IDLIST of the primary key column.  keyColumn is
-  ** the index of the primary key as it appears in IDLIST, not as
-  ** is appears in the original table.  (The index of the primary
-  ** key in the original table is pTab->iPKey.)
-  */
-  if( pColumn ){
-    for(i=0; i<pColumn->nId; i++){
-      pColumn->a[i].idx = -1;
-    }
-    for(i=0; i<pColumn->nId; i++){
-      for(j=0; j<pTab->nCol; j++){
-        if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
-          pColumn->a[i].idx = j;
-          if( j==pTab->iPKey ){
-            keyColumn = i;
-          }
-          break;
-        }
-      }
-      if( j>=pTab->nCol ){
-        if( sqlite3IsRowid(pColumn->a[i].zName) ){
-          keyColumn = i;
-        }else{
-          sqlite3ErrorMsg(pParse, "table %S has no column named %s",
-              pTabList, 0, pColumn->a[i].zName);
-          pParse->nErr++;
-          goto insert_cleanup;
-        }
-      }
-    }
+  if( sqlite3BtreeIsInReadTrans(pDb->pBt) || sqlite3BtreeIsInBackup(pDb->pBt) ){
+    sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
+    goto detach_error;
   }
 
-  /* If there is no IDLIST term but the table has an integer primary
-  ** key, the set the keyColumn variable to the primary key column index
-  ** in the original table definition.
-  */
-  if( pColumn==0 && nColumn>0 ){
-    keyColumn = pTab->iPKey;
-  }
+  sqlite3BtreeClose(pDb->pBt);
+  pDb->pBt = 0;
+  pDb->pSchema = 0;
+  sqlite3ResetInternalSchema(db, 0);
+  return;
 
-  /* Open the temp table for FOR EACH ROW triggers
-  */
-  if( triggers_exist ){
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
-    sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
-  }
-    
-  /* Initialize the count of rows to be inserted
-  */
-  if( db->flags & SQLITE_CountRows ){
-    regRowCount = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
-  }
+detach_error:
+  sqlite3_result_error(context, zErr, -1);
+}
 
-  /* If this is not a view, open the table and and all indices */
-  if( !isView ){
-    int nIdx;
-    int i;
+/*
+** This procedure generates VDBE code for a single invocation of either the
+** sqlite_detach() or sqlite_attach() SQL user functions.
+*/
+static void codeAttach(
+  Parse *pParse,       /* The parser context */
+  int type,            /* Either SQLITE_ATTACH or SQLITE_DETACH */
+  FuncDef *pFunc,      /* FuncDef wrapper for detachFunc() or attachFunc() */
+  Expr *pAuthArg,      /* Expression to pass to authorization callback */
+  Expr *pFilename,     /* Name of database file */
+  Expr *pDbname,       /* Name of the database to use internally */
+  Expr *pKey           /* Database key for encryption extension */
+){
+  int rc;
+  NameContext sName;
+  Vdbe *v;
+  sqlite3* db = pParse->db;
+  int regArgs;
 
-    baseCur = pParse->nTab;
-    nIdx = sqlite3OpenTableAndIndices(pParse, pTab, baseCur, OP_OpenWrite);
-    aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1));
-    if( aRegIdx==0 ){
-      goto insert_cleanup;
-    }
-    for(i=0; i<nIdx; i++){
-      aRegIdx[i] = ++pParse->nMem;
-    }
-  }
+  memset(&sName, 0, sizeof(NameContext));
+  sName.pParse = pParse;
 
-  /* If the data source is a temporary table, then we have to create
-  ** a loop because there might be multiple rows of data.  If the data
-  ** source is a subroutine call from the SELECT statement, then we need
-  ** to launch the SELECT statement processing.
-  */
-  if( useTempTable ){
-    iBreak = sqlite3VdbeMakeLabel(v);
-    sqlite3VdbeAddOp2(v, OP_Rewind, srcTab, iBreak);
-    iCont = sqlite3VdbeCurrentAddr(v);
-  }else if( pSelect ){
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iSelectLoop);
-    sqlite3VdbeResolveLabel(v, iInsertBlock);
+  if( 
+      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
+      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
+      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
+  ){
+    pParse->nErr++;
+    goto attach_end;
   }
 
-  /* Allocate registers for holding the rowid of the new row,
-  ** the content of the new row, and the assemblied row record.
-  */
-  regRecord = ++pParse->nMem;
-  regRowid = regIns = pParse->nMem+1;
-  pParse->nMem += pTab->nCol + 1;
-  if( IsVirtual(pTab) ){
-    regRowid++;
-    pParse->nMem++;
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  if( pAuthArg ){
+    char *zAuthArg = pAuthArg->u.zToken;
+    if( NEVER(zAuthArg==0) ){
+      goto attach_end;
+    }
+    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
+    if(rc!=SQLITE_OK ){
+      goto attach_end;
+    }
   }
-  regData = regRowid+1;
+#endif /* SQLITE_OMIT_AUTHORIZATION */
 
-  /* Run the BEFORE and INSTEAD OF triggers, if there are any
-  */
-  endOfLoop = sqlite3VdbeMakeLabel(v);
-  if( triggers_exist & TRIGGER_BEFORE ){
-    int regRowid;
-    int regCols;
-    int regRec;
 
-    /* build the NEW.* reference row.  Note that if there is an INTEGER
-    ** PRIMARY KEY into which a NULL is being inserted, that NULL will be
-    ** translated into a unique ID for the row.  But on a BEFORE trigger,
-    ** we do not know what the unique ID will be (because the insert has
-    ** not happened yet) so we substitute a rowid of -1
-    */
-    regRowid = sqlite3GetTempReg(pParse);
-    if( keyColumn<0 ){
-      sqlite3VdbeAddOp2(v, OP_Integer, -1, regRowid);
-    }else if( useTempTable ){
-      sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid);
-    }else{
-      int j1;
-      assert( pSelect==0 );  /* Otherwise useTempTable is true */
-      sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regRowid);
-      j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid);
-      sqlite3VdbeAddOp2(v, OP_Integer, -1, regRowid);
-      sqlite3VdbeJumpHere(v, j1);
-      sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
-    }
+  v = sqlite3GetVdbe(pParse);
+  regArgs = sqlite3GetTempRange(pParse, 4);
+  sqlite3ExprCode(pParse, pFilename, regArgs);
+  sqlite3ExprCode(pParse, pDbname, regArgs+1);
+  sqlite3ExprCode(pParse, pKey, regArgs+2);
 
-    /* Cannot have triggers on a virtual table. If it were possible,
-    ** this block would have to account for hidden column.
-    */
-    assert(!IsVirtual(pTab));
+  assert( v || db->mallocFailed );
+  if( v ){
+    sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-pFunc->nArg, regArgs+3);
+    assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg );
+    sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
+    sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
 
-    /* Create the new column data
+    /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
+    ** statement only). For DETACH, set it to false (expire all existing
+    ** statements).
     */
-    regCols = sqlite3GetTempRange(pParse, pTab->nCol);
-    for(i=0; i<pTab->nCol; i++){
-      if( pColumn==0 ){
-        j = i;
-      }else{
-        for(j=0; j<pColumn->nId; j++){
-          if( pColumn->a[j].idx==i ) break;
-        }
-      }
-      if( pColumn && j>=pColumn->nId ){
-        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i);
-      }else if( useTempTable ){
-        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i); 
-      }else{
-        assert( pSelect==0 ); /* Otherwise useTempTable is true */
-        sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i);
-      }
-    }
-    regRec = sqlite3GetTempReg(pParse);
-    sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRec);
+    sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
+  }
+  
+attach_end:
+  sqlite3ExprDelete(db, pFilename);
+  sqlite3ExprDelete(db, pDbname);
+  sqlite3ExprDelete(db, pKey);
+}
 
-    /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
-    ** do not attempt any conversions before assembling the record.
-    ** If this is a real table, attempt conversions as required by the
-    ** table column affinities.
-    */
-    if( !isView ){
-      sqlite3TableAffinityStr(v, pTab);
-    }
-    sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRec, regRowid);
-    sqlite3ReleaseTempReg(pParse, regRec);
-    sqlite3ReleaseTempReg(pParse, regRowid);
-    sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
+/*
+** Called by the parser to compile a DETACH statement.
+**
+**     DETACH pDbname
+*/
+SQLITE_PRIVATE void sqlite3Detach(Parse *pParse, Expr *pDbname){
+  static FuncDef detach_func = {
+    1,                /* nArg */
+    SQLITE_UTF8,      /* iPrefEnc */
+    0,                /* flags */
+    0,                /* pUserData */
+    0,                /* pNext */
+    detachFunc,       /* xFunc */
+    0,                /* xStep */
+    0,                /* xFinalize */
+    "sqlite_detach",  /* zName */
+    0                 /* pHash */
+  };
+  codeAttach(pParse, SQLITE_DETACH, &detach_func, pDbname, 0, 0, pDbname);
+}
 
-    /* Fire BEFORE or INSTEAD OF triggers */
-    if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_BEFORE, pTab, 
-        newIdx, -1, onError, endOfLoop, 0, 0) ){
-      goto insert_cleanup;
+/*
+** Called by the parser to compile an ATTACH statement.
+**
+**     ATTACH p AS pDbname KEY pKey
+*/
+SQLITE_PRIVATE void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){
+  static FuncDef attach_func = {
+    3,                /* nArg */
+    SQLITE_UTF8,      /* iPrefEnc */
+    0,                /* flags */
+    0,                /* pUserData */
+    0,                /* pNext */
+    attachFunc,       /* xFunc */
+    0,                /* xStep */
+    0,                /* xFinalize */
+    "sqlite_attach",  /* zName */
+    0                 /* pHash */
+  };
+  codeAttach(pParse, SQLITE_ATTACH, &attach_func, p, p, pDbname, pKey);
+}
+#endif /* SQLITE_OMIT_ATTACH */
+
+/*
+** Initialize a DbFixer structure.  This routine must be called prior
+** to passing the structure to one of the sqliteFixAAAA() routines below.
+**
+** The return value indicates whether or not fixation is required.  TRUE
+** means we do need to fix the database references, FALSE means we do not.
+*/
+SQLITE_PRIVATE int sqlite3FixInit(
+  DbFixer *pFix,      /* The fixer to be initialized */
+  Parse *pParse,      /* Error messages will be written here */
+  int iDb,            /* This is the database that must be used */
+  const char *zType,  /* "view", "trigger", or "index" */
+  const Token *pName  /* Name of the view, trigger, or index */
+){
+  sqlite3 *db;
+
+  if( NEVER(iDb<0) || iDb==1 ) return 0;
+  db = pParse->db;
+  assert( db->nDb>iDb );
+  pFix->pParse = pParse;
+  pFix->zDb = db->aDb[iDb].zName;
+  pFix->zType = zType;
+  pFix->pName = pName;
+  return 1;
+}
+
+/*
+** The following set of routines walk through the parse tree and assign
+** a specific database to all table references where the database name
+** was left unspecified in the original SQL statement.  The pFix structure
+** must have been initialized by a prior call to sqlite3FixInit().
+**
+** These routines are used to make sure that an index, trigger, or
+** view in one database does not refer to objects in a different database.
+** (Exception: indices, triggers, and views in the TEMP database are
+** allowed to refer to anything.)  If a reference is explicitly made
+** to an object in a different database, an error message is added to
+** pParse->zErrMsg and these routines return non-zero.  If everything
+** checks out, these routines return 0.
+*/
+SQLITE_PRIVATE int sqlite3FixSrcList(
+  DbFixer *pFix,       /* Context of the fixation */
+  SrcList *pList       /* The Source list to check and modify */
+){
+  int i;
+  const char *zDb;
+  struct SrcList_item *pItem;
+
+  if( NEVER(pList==0) ) return 0;
+  zDb = pFix->zDb;
+  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
+    if( pItem->zDatabase==0 ){
+      pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb);
+    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
+      sqlite3ErrorMsg(pFix->pParse,
+         "%s %T cannot reference objects in database %s",
+         pFix->zType, pFix->pName, pItem->zDatabase);
+      return 1;
     }
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
+    if( sqlite3FixSelect(pFix, pItem->pSelect) ) return 1;
+    if( sqlite3FixExpr(pFix, pItem->pOn) ) return 1;
+#endif
   }
-
-  /* Push the record number for the new entry onto the stack.  The
-  ** record number is a randomly generate integer created by NewRowid
-  ** except when the table has an INTEGER PRIMARY KEY column, in which
-  ** case the record number is the same as that column. 
-  */
-  if( !isView ){
-    if( IsVirtual(pTab) ){
-      /* The row that the VUpdate opcode will delete: none */
-      sqlite3VdbeAddOp2(v, OP_Null, 0, regIns);
+  return 0;
+}
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE int sqlite3FixSelect(
+  DbFixer *pFix,       /* Context of the fixation */
+  Select *pSelect      /* The SELECT statement to be fixed to one database */
+){
+  while( pSelect ){
+    if( sqlite3FixExprList(pFix, pSelect->pEList) ){
+      return 1;
     }
-    if( keyColumn>=0 ){
-      if( useTempTable ){
-        sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid);
-      }else if( pSelect ){
-        sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+keyColumn, regRowid);
-      }else{
-        VdbeOp *pOp;
-        sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regRowid);
-        pOp = sqlite3VdbeGetOp(v, sqlite3VdbeCurrentAddr(v) - 1);
-        if( pOp && pOp->opcode==OP_Null ){
-          appendFlag = 1;
-          pOp->opcode = OP_NewRowid;
-          pOp->p1 = baseCur;
-          pOp->p2 = regRowid;
-          pOp->p3 = regAutoinc;
-        }
-      }
-      /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
-      ** to generate a unique primary key value.
-      */
-      if( !appendFlag ){
-        int j1;
-        j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid);
-        sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
-        sqlite3VdbeJumpHere(v, j1);
-        sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
-      }
-    }else if( IsVirtual(pTab) ){
-      sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid);
-    }else{
-      sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
-      appendFlag = 1;
+    if( sqlite3FixSrcList(pFix, pSelect->pSrc) ){
+      return 1;
     }
-    autoIncStep(pParse, regAutoinc, regRowid);
-
-    /* Push onto the stack, data for all columns of the new entry, beginning
-    ** with the first column.
-    */
-    nHidden = 0;
-    for(i=0; i<pTab->nCol; i++){
-      int iRegStore = regRowid+1+i;
-      if( i==pTab->iPKey ){
-        /* The value of the INTEGER PRIMARY KEY column is always a NULL.
-        ** Whenever this column is read, the record number will be substituted
-        ** in its place.  So will fill this column with a NULL to avoid
-        ** taking up data space with information that will never be used. */
-        sqlite3VdbeAddOp2(v, OP_Null, 0, iRegStore);
-        continue;
-      }
-      if( pColumn==0 ){
-        if( IsHiddenColumn(&pTab->aCol[i]) ){
-          assert( IsVirtual(pTab) );
-          j = -1;
-          nHidden++;
-        }else{
-          j = i - nHidden;
-        }
-      }else{
-        for(j=0; j<pColumn->nId; j++){
-          if( pColumn->a[j].idx==i ) break;
-        }
-      }
-      if( j<0 || nColumn==0 || (pColumn && j>=pColumn->nId) ){
-        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, iRegStore);
-      }else if( useTempTable ){
-        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, iRegStore); 
-      }else if( pSelect ){
-        sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore);
-      }else{
-        sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore);
-      }
+    if( sqlite3FixExpr(pFix, pSelect->pWhere) ){
+      return 1;
     }
-
-    /* Generate code to check constraints and generate index keys and
-    ** do the insertion.
-    */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( IsVirtual(pTab) ){
-      sqlite3VtabMakeWritable(pParse, pTab);
-      sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns,
-                     (const char*)pTab->pVtab, P4_VTAB);
-    }else
-#endif
-    {
-      sqlite3GenerateConstraintChecks(
-          pParse,
-          pTab,
-          baseCur,
-          regIns,
-          aRegIdx,
-          keyColumn>=0,
-          0,
-          onError,
-          endOfLoop
-      );
-      sqlite3CompleteInsertion(
-          pParse,
-          pTab,
-          baseCur,
-          regIns,
-          aRegIdx,
-          0,
-          0,
-          (triggers_exist & TRIGGER_AFTER)!=0 ? newIdx : -1,
-          appendFlag
-       );
+    if( sqlite3FixExpr(pFix, pSelect->pHaving) ){
+      return 1;
     }
+    pSelect = pSelect->pPrior;
   }
-
-  /* Update the count of rows that are inserted
-  */
-  if( (db->flags & SQLITE_CountRows)!=0 ){
-    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
-  }
-
-  if( triggers_exist ){
-    /* Code AFTER triggers */
-    if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_AFTER, pTab,
-          newIdx, -1, onError, endOfLoop, 0, 0) ){
-      goto insert_cleanup;
+  return 0;
+}
+SQLITE_PRIVATE int sqlite3FixExpr(
+  DbFixer *pFix,     /* Context of the fixation */
+  Expr *pExpr        /* The expression to be fixed to one database */
+){
+  while( pExpr ){
+    if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ) break;
+    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+      if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1;
+    }else{
+      if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1;
     }
+    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
+      return 1;
+    }
+    pExpr = pExpr->pLeft;
   }
-
-  /* The bottom of the loop, if the data source is a SELECT statement
-  */
-  sqlite3VdbeResolveLabel(v, endOfLoop);
-  if( useTempTable ){
-    sqlite3VdbeAddOp2(v, OP_Next, srcTab, iCont);
-    sqlite3VdbeResolveLabel(v, iBreak);
-    sqlite3VdbeAddOp2(v, OP_Close, srcTab, 0);
-  }else if( pSelect ){
-    sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-    sqlite3VdbeResolveLabel(v, iCleanup);
-  }
-
-  if( !IsVirtual(pTab) && !isView ){
-    /* Close all tables opened */
-    sqlite3VdbeAddOp2(v, OP_Close, baseCur, 0);
-    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
-      sqlite3VdbeAddOp2(v, OP_Close, idx+baseCur, 0);
+  return 0;
+}
+SQLITE_PRIVATE int sqlite3FixExprList(
+  DbFixer *pFix,     /* Context of the fixation */
+  ExprList *pList    /* The expression to be fixed to one database */
+){
+  int i;
+  struct ExprList_item *pItem;
+  if( pList==0 ) return 0;
+  for(i=0, pItem=pList->a; i<pList->nExpr; i++, pItem++){
+    if( sqlite3FixExpr(pFix, pItem->pExpr) ){
+      return 1;
     }
   }
+  return 0;
+}
+#endif
 
-  /* Update the sqlite_sequence table by storing the content of the
-  ** counter value in memory regAutoinc back into the sqlite_sequence
-  ** table.
-  */
-  autoIncEnd(pParse, iDb, pTab, regAutoinc);
-
-  /*
-  ** Return the number of rows inserted. If this routine is 
-  ** generating code because of a call to sqlite3NestedParse(), do not
-  ** invoke the callback function.
-  */
-  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
-    sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", P4_STATIC);
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE int sqlite3FixTriggerStep(
+  DbFixer *pFix,     /* Context of the fixation */
+  TriggerStep *pStep /* The trigger step be fixed to one database */
+){
+  while( pStep ){
+    if( sqlite3FixSelect(pFix, pStep->pSelect) ){
+      return 1;
+    }
+    if( sqlite3FixExpr(pFix, pStep->pWhere) ){
+      return 1;
+    }
+    if( sqlite3FixExprList(pFix, pStep->pExprList) ){
+      return 1;
+    }
+    pStep = pStep->pNext;
   }
-
-insert_cleanup:
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprListDelete(pList);
-  sqlite3SelectDelete(pSelect);
-  sqlite3IdListDelete(pColumn);
-  sqlite3_free(aRegIdx);
+  return 0;
 }
+#endif
 
+/************** End of attach.c **********************************************/
+/************** Begin file auth.c ********************************************/
 /*
-** Generate code to do constraint checks prior to an INSERT or an UPDATE.
-**
-** The input is a range of consecutive registers as follows:
-**
-**    1.  The rowid of the row to be updated before the update.  This
-**        value is omitted unless we are doing an UPDATE that involves a
-**        change to the record number or writing to a virtual table.
-**
-**    2.  The rowid of the row after the update.
-**
-**    3.  The data in the first column of the entry after the update.
-**
-**    i.  Data from middle columns...
-**
-**    N.  The data in the last column of the entry after the update.
-**
-** The regRowid parameter is the index of the register containing (2).
-**
-** The old rowid shown as entry (1) above is omitted unless both isUpdate
-** and rowidChng are 1.  isUpdate is true for UPDATEs and false for
-** INSERTs.  RowidChng means that the new rowid is explicitly specified by
-** the update or insert statement.  If rowidChng is false, it means that
-** the rowid is computed automatically in an insert or that the rowid value
-** is not modified by the update.
-**
-** The code generated by this routine store new index entries into
-** registers identified by aRegIdx[].  No index entry is created for
-** indices where aRegIdx[i]==0.  The order of indices in aRegIdx[] is
-** the same as the order of indices on the linked list of indices
-** attached to the table.
-**
-** This routine also generates code to check constraints.  NOT NULL,
-** CHECK, and UNIQUE constraints are all checked.  If a constraint fails,
-** then the appropriate action is performed.  There are five possible
-** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
-**
-**  Constraint type  Action       What Happens
-**  ---------------  ----------   ----------------------------------------
-**  any              ROLLBACK     The current transaction is rolled back and
-**                                sqlite3_exec() returns immediately with a
-**                                return code of SQLITE_CONSTRAINT.
+** 2003 January 11
 **
-**  any              ABORT        Back out changes from the current command
-**                                only (do not do a complete rollback) then
-**                                cause sqlite3_exec() to return immediately
-**                                with SQLITE_CONSTRAINT.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-**  any              FAIL         Sqlite_exec() returns immediately with a
-**                                return code of SQLITE_CONSTRAINT.  The
-**                                transaction is not rolled back and any
-**                                prior changes are retained.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-**  any              IGNORE       The record number and data is popped from
-**                                the stack and there is an immediate jump
-**                                to label ignoreDest.
+*************************************************************************
+** This file contains code used to implement the sqlite3_set_authorizer()
+** API.  This facility is an optional feature of the library.  Embedded
+** systems that do not need this facility may omit it by recompiling
+** the library with -DSQLITE_OMIT_AUTHORIZATION=1
 **
-**  NOT NULL         REPLACE      The NULL value is replace by the default
-**                                value for that column.  If the default value
-**                                is NULL, the action is the same as ABORT.
+** $Id: auth.c,v 1.32 2009/07/02 18:40:35 danielk1977 Exp $
+*/
+
+/*
+** All of the code in this file may be omitted by defining a single
+** macro.
+*/
+#ifndef SQLITE_OMIT_AUTHORIZATION
+
+/*
+** Set or clear the access authorization function.
 **
-**  UNIQUE           REPLACE      The other row that conflicts with the row
-**                                being inserted is removed.
+** The access authorization function is be called during the compilation
+** phase to verify that the user has read and/or write access permission on
+** various fields of the database.  The first argument to the auth function
+** is a copy of the 3rd argument to this routine.  The second argument
+** to the auth function is one of these constants:
 **
-**  CHECK            REPLACE      Illegal.  The results in an exception.
+**       SQLITE_CREATE_INDEX
+**       SQLITE_CREATE_TABLE
+**       SQLITE_CREATE_TEMP_INDEX
+**       SQLITE_CREATE_TEMP_TABLE
+**       SQLITE_CREATE_TEMP_TRIGGER
+**       SQLITE_CREATE_TEMP_VIEW
+**       SQLITE_CREATE_TRIGGER
+**       SQLITE_CREATE_VIEW
+**       SQLITE_DELETE
+**       SQLITE_DROP_INDEX
+**       SQLITE_DROP_TABLE
+**       SQLITE_DROP_TEMP_INDEX
+**       SQLITE_DROP_TEMP_TABLE
+**       SQLITE_DROP_TEMP_TRIGGER
+**       SQLITE_DROP_TEMP_VIEW
+**       SQLITE_DROP_TRIGGER
+**       SQLITE_DROP_VIEW
+**       SQLITE_INSERT
+**       SQLITE_PRAGMA
+**       SQLITE_READ
+**       SQLITE_SELECT
+**       SQLITE_TRANSACTION
+**       SQLITE_UPDATE
 **
-** Which action to take is determined by the overrideError parameter.
-** Or if overrideError==OE_Default, then the pParse->onError parameter
-** is used.  Or if pParse->onError==OE_Default then the onError value
-** for the constraint is used.
+** The third and fourth arguments to the auth function are the name of
+** the table and the column that are being accessed.  The auth function
+** should return either SQLITE_OK, SQLITE_DENY, or SQLITE_IGNORE.  If
+** SQLITE_OK is returned, it means that access is allowed.  SQLITE_DENY
+** means that the SQL statement will never-run - the sqlite3_exec() call
+** will return with an error.  SQLITE_IGNORE means that the SQL statement
+** should run but attempts to read the specified column will return NULL
+** and attempts to write the column will be ignored.
 **
-** The calling routine must open a read/write cursor for pTab with
-** cursor number "baseCur".  All indices of pTab must also have open
-** read/write cursors with cursor number baseCur+i for the i-th cursor.
-** Except, if there is no possibility of a REPLACE action then
-** cursors do not need to be open for indices where aRegIdx[i]==0.
+** Setting the auth function to NULL disables this hook.  The default
+** setting of the auth function is NULL.
 */
-SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
-  Parse *pParse,      /* The parser context */
-  Table *pTab,        /* the table into which we are inserting */
-  int baseCur,        /* Index of a read/write cursor pointing at pTab */
-  int regRowid,       /* Index of the range of input registers */
-  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
-  int rowidChng,      /* True if the rowid might collide with existing entry */
-  int isUpdate,       /* True for UPDATE, False for INSERT */
-  int overrideError,  /* Override onError to this if not OE_Default */
-  int ignoreDest      /* Jump to this label on an OE_Ignore resolution */
+SQLITE_API int sqlite3_set_authorizer(
+  sqlite3 *db,
+  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
+  void *pArg
 ){
-  int i;
-  Vdbe *v;
-  int nCol;
-  int onError;
-  int j1, j2, j3;     /* Addresses of jump instructions */
-  int regData;        /* Register containing first data column */
-  int iCur;
-  Index *pIdx;
-  int seenReplace = 0;
-  int hasTwoRowids = (isUpdate && rowidChng);
+  sqlite3_mutex_enter(db->mutex);
+  db->xAuth = xAuth;
+  db->pAuthArg = pArg;
+  sqlite3ExpirePreparedStatements(db);
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
 
-  v = sqlite3GetVdbe(pParse);
-  assert( v!=0 );
-  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
-  nCol = pTab->nCol;
-  regData = regRowid + 1;
+/*
+** Write an error message into pParse->zErrMsg that explains that the
+** user-supplied authorization function returned an illegal value.
+*/
+static void sqliteAuthBadReturnCode(Parse *pParse){
+  sqlite3ErrorMsg(pParse, "authorizer malfunction");
+  pParse->rc = SQLITE_ERROR;
+}
 
+/*
+** Invoke the authorization callback for permission to read column zCol from
+** table zTab in database zDb. This function assumes that an authorization
+** callback has been registered (i.e. that sqlite3.xAuth is not NULL).
+**
+** If SQLITE_IGNORE is returned and pExpr is not NULL, then pExpr is changed
+** to an SQL NULL expression. Otherwise, if pExpr is NULL, then SQLITE_IGNORE
+** is treated as SQLITE_DENY. In this case an error is left in pParse.
+*/
+SQLITE_PRIVATE int sqlite3AuthReadCol(
+  Parse *pParse,                  /* The parser context */
+  const char *zTab,               /* Table name */
+  const char *zCol,               /* Column name */
+  int iDb                         /* Index of containing database. */
+){
+  sqlite3 *db = pParse->db;       /* Database handle */
+  char *zDb = db->aDb[iDb].zName; /* Name of attached database */
+  int rc;                         /* Auth callback return code */
 
-  /* Test all NOT NULL constraints.
-  */
-  for(i=0; i<nCol; i++){
-    if( i==pTab->iPKey ){
-      continue;
-    }
-    onError = pTab->aCol[i].notNull;
-    if( onError==OE_None ) continue;
-    if( overrideError!=OE_Default ){
-      onError = overrideError;
-    }else if( onError==OE_Default ){
-      onError = OE_Abort;
-    }
-    if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
-      onError = OE_Abort;
-    }
-    j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regData+i);
-    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
-        || onError==OE_Ignore || onError==OE_Replace );
-    switch( onError ){
-      case OE_Rollback:
-      case OE_Abort:
-      case OE_Fail: {
-        char *zMsg = 0;
-        sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
-        sqlite3SetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
-                        " may not be NULL", (char*)0);
-        sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
-        break;
-      }
-      case OE_Ignore: {
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
-        break;
-      }
-      case OE_Replace: {
-        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regData+i);
-        break;
-      }
+  rc = db->xAuth(db->pAuthArg, SQLITE_READ, zTab,zCol,zDb,pParse->zAuthContext);
+  if( rc==SQLITE_DENY ){
+    if( db->nDb>2 || iDb!=0 ){
+      sqlite3ErrorMsg(pParse, "access to %s.%s.%s is prohibited",zDb,zTab,zCol);
+    }else{
+      sqlite3ErrorMsg(pParse, "access to %s.%s is prohibited", zTab, zCol);
     }
-    sqlite3VdbeJumpHere(v, j1);
+    pParse->rc = SQLITE_AUTH;
+  }else if( rc!=SQLITE_IGNORE && rc!=SQLITE_OK ){
+    sqliteAuthBadReturnCode(pParse);
   }
+  return rc;
+}
 
-  /* Test all CHECK constraints
-  */
-#ifndef SQLITE_OMIT_CHECK
-  if( pTab->pCheck && (pParse->db->flags & SQLITE_IgnoreChecks)==0 ){
-    int allOk = sqlite3VdbeMakeLabel(v);
-    pParse->ckBase = regData;
-    sqlite3ExprIfTrue(pParse, pTab->pCheck, allOk, SQLITE_JUMPIFNULL);
-    onError = overrideError!=OE_Default ? overrideError : OE_Abort;
-    if( onError==OE_Ignore ){
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
-    }else{
-      sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
-    }
-    sqlite3VdbeResolveLabel(v, allOk);
-  }
-#endif /* !defined(SQLITE_OMIT_CHECK) */
+/*
+** The pExpr should be a TK_COLUMN expression.  The table referred to
+** is in pTabList or else it is the NEW or OLD table of a trigger.  
+** Check to see if it is OK to read this particular column.
+**
+** If the auth function returns SQLITE_IGNORE, change the TK_COLUMN 
+** instruction into a TK_NULL.  If the auth function returns SQLITE_DENY,
+** then generate an error.
+*/
+SQLITE_PRIVATE void sqlite3AuthRead(
+  Parse *pParse,        /* The parser context */
+  Expr *pExpr,          /* The expression to check authorization on */
+  Schema *pSchema,      /* The schema of the expression */
+  SrcList *pTabList     /* All table that pExpr might refer to */
+){
+  sqlite3 *db = pParse->db;
+  Table *pTab = 0;      /* The table being read */
+  const char *zCol;     /* Name of the column of the table */
+  int iSrc;             /* Index in pTabList->a[] of table being read */
+  int iDb;              /* The index of the database the expression refers to */
+  int iCol;             /* Index of column in table */
 
-  /* If we have an INTEGER PRIMARY KEY, make sure the primary key
-  ** of the new record does not previously exist.  Except, if this
-  ** is an UPDATE and the primary key is not changing, that is OK.
-  */
-  if( rowidChng ){
-    onError = pTab->keyConf;
-    if( overrideError!=OE_Default ){
-      onError = overrideError;
-    }else if( onError==OE_Default ){
-      onError = OE_Abort;
-    }
-    
-    if( onError!=OE_Replace || pTab->pIndex ){
-      if( isUpdate ){
-        j2 = sqlite3VdbeAddOp3(v, OP_Eq, regRowid, 0, regRowid-1);
-      }
-      j3 = sqlite3VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid);
-      switch( onError ){
-        default: {
-          onError = OE_Abort;
-          /* Fall thru into the next case */
-        }
-        case OE_Rollback:
-        case OE_Abort:
-        case OE_Fail: {
-          sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0,
-                           "PRIMARY KEY must be unique", P4_STATIC);
-          break;
-        }
-        case OE_Replace: {
-          sqlite3GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
-          seenReplace = 1;
-          break;
-        }
-        case OE_Ignore: {
-          assert( seenReplace==0 );
-          sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
-          break;
-        }
-      }
-      sqlite3VdbeJumpHere(v, j3);
-      if( isUpdate ){
-        sqlite3VdbeJumpHere(v, j2);
-      }
-    }
+  if( db->xAuth==0 ) return;
+  iDb = sqlite3SchemaToIndex(pParse->db, pSchema);
+  if( iDb<0 ){
+    /* An attempt to read a column out of a subquery or other
+    ** temporary table. */
+    return;
   }
 
-  /* Test all UNIQUE constraints by creating entries for each UNIQUE
-  ** index and making sure that duplicate entries do not already exist.
-  ** Add the new records to the indices as we go.
-  */
-  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
-    int regIdx;
-    int regR;
-
-    if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */
-
-    /* Create a key for accessing the index entry */
-    regIdx = sqlite3GetTempRange(pParse, pIdx->nColumn+1);
-    for(i=0; i<pIdx->nColumn; i++){
-      int idx = pIdx->aiColumn[i];
-      if( idx==pTab->iPKey ){
-        sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_SCopy, regData+idx, regIdx+i);
-      }
-    }
-    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
-    sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]);
-    sqlite3IndexAffinityStr(v, pIdx);
-    sqlite3ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1);
-    sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
-
-    /* Find out what action to take in case there is an indexing conflict */
-    onError = pIdx->onError;
-    if( onError==OE_None ) continue;  /* pIdx is not a UNIQUE index */
-    if( overrideError!=OE_Default ){
-      onError = overrideError;
-    }else if( onError==OE_Default ){
-      onError = OE_Abort;
-    }
-    if( seenReplace ){
-      if( onError==OE_Ignore ) onError = OE_Replace;
-      else if( onError==OE_Fail ) onError = OE_Abort;
-    }
-    
-
-    /* Check to see if the new index entry will be unique */
-    j2 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdx, 0, pIdx->nColumn);
-    regR = sqlite3GetTempReg(pParse);
-    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid-hasTwoRowids, regR);
-    j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
-                           regR, (char*)aRegIdx[iCur],
-                           P4_INT32);
-
-    /* Generate code that executes if the new index entry is not unique */
-    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
-        || onError==OE_Ignore || onError==OE_Replace );
-    switch( onError ){
-      case OE_Rollback:
-      case OE_Abort:
-      case OE_Fail: {
-        int j, n1, n2;
-        char zErrMsg[200];
-        sqlite3_snprintf(sizeof(zErrMsg), zErrMsg,
-                         pIdx->nColumn>1 ? "columns " : "column ");
-        n1 = strlen(zErrMsg);
-        for(j=0; j<pIdx->nColumn && n1<sizeof(zErrMsg)-30; j++){
-          char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
-          n2 = strlen(zCol);
-          if( j>0 ){
-            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], ", ");
-            n1 += 2;
-          }
-          if( n1+n2>sizeof(zErrMsg)-30 ){
-            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "...");
-            n1 += 3;
-            break;
-          }else{
-            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "%s", zCol);
-            n1 += n2;
-          }
-        }
-        sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], 
-            pIdx->nColumn>1 ? " are not unique" : " is not unique");
-        sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0, zErrMsg,0);
-        break;
-      }
-      case OE_Ignore: {
-        assert( seenReplace==0 );
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
-        break;
-      }
-      case OE_Replace: {
-        sqlite3GenerateRowDelete(pParse, pTab, baseCur, regR, 0);
-        seenReplace = 1;
+  assert( pExpr->op==TK_COLUMN || pExpr->op==TK_TRIGGER );
+  if( pExpr->op==TK_TRIGGER ){
+    pTab = pParse->pTriggerTab;
+  }else{
+    assert( pTabList );
+    for(iSrc=0; ALWAYS(iSrc<pTabList->nSrc); iSrc++){
+      if( pExpr->iTable==pTabList->a[iSrc].iCursor ){
+        pTab = pTabList->a[iSrc].pTab;
         break;
       }
     }
-    sqlite3VdbeJumpHere(v, j2);
-    sqlite3VdbeJumpHere(v, j3);
-    sqlite3ReleaseTempReg(pParse, regR);
+  }
+  iCol = pExpr->iColumn;
+  if( NEVER(pTab==0) ) return;
+
+  if( iCol>=0 ){
+    assert( iCol<pTab->nCol );
+    zCol = pTab->aCol[iCol].zName;
+  }else if( pTab->iPKey>=0 ){
+    assert( pTab->iPKey<pTab->nCol );
+    zCol = pTab->aCol[pTab->iPKey].zName;
+  }else{
+    zCol = "ROWID";
+  }
+  assert( iDb>=0 && iDb<db->nDb );
+  if( SQLITE_IGNORE==sqlite3AuthReadCol(pParse, pTab->zName, zCol, iDb) ){
+    pExpr->op = TK_NULL;
   }
 }
 
 /*
-** This routine generates code to finish the INSERT or UPDATE operation
-** that was started by a prior call to sqlite3GenerateConstraintChecks.
-** A consecutive range of registers starting at regRowid contains the
-** rowid and the content to be inserted.
-**
-** The arguments to this routine should be the same as the first six
-** arguments to sqlite3GenerateConstraintChecks.
+** Do an authorization check using the code and arguments given.  Return
+** either SQLITE_OK (zero) or SQLITE_IGNORE or SQLITE_DENY.  If SQLITE_DENY
+** is returned, then the error count and error message in pParse are
+** modified appropriately.
 */
-SQLITE_PRIVATE void sqlite3CompleteInsertion(
-  Parse *pParse,      /* The parser context */
-  Table *pTab,        /* the table into which we are inserting */
-  int baseCur,        /* Index of a read/write cursor pointing at pTab */
-  int regRowid,       /* Range of content */
-  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
-  int rowidChng,      /* True if the record number will change */
-  int isUpdate,       /* True for UPDATE, False for INSERT */
-  int newIdx,         /* Index of NEW table for triggers.  -1 if none */
-  int appendBias      /* True if this is likely to be an append */
+SQLITE_PRIVATE int sqlite3AuthCheck(
+  Parse *pParse,
+  int code,
+  const char *zArg1,
+  const char *zArg2,
+  const char *zArg3
 ){
-  int i;
-  Vdbe *v;
-  int nIdx;
-  Index *pIdx;
-  int pik_flags;
-  int regData;
-  int regRec;
+  sqlite3 *db = pParse->db;
+  int rc;
 
-  v = sqlite3GetVdbe(pParse);
-  assert( v!=0 );
-  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
-  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
-  for(i=nIdx-1; i>=0; i--){
-    if( aRegIdx[i]==0 ) continue;
-    sqlite3VdbeAddOp2(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i]);
-  }
-  regData = regRowid + 1;
-  regRec = sqlite3GetTempReg(pParse);
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
-  sqlite3TableAffinityStr(v, pTab);
-  sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol);
-#ifndef SQLITE_OMIT_TRIGGER
-  if( newIdx>=0 ){
-    sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRec, regRowid);
-  }
-#endif
-  if( pParse->nested ){
-    pik_flags = 0;
-  }else{
-    pik_flags = OPFLAG_NCHANGE;
-    pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID);
+  /* Don't do any authorization checks if the database is initialising
+  ** or if the parser is being invoked from within sqlite3_declare_vtab.
+  */
+  if( db->init.busy || IN_DECLARE_VTAB ){
+    return SQLITE_OK;
   }
-  if( appendBias ){
-    pik_flags |= OPFLAG_APPEND;
+
+  if( db->xAuth==0 ){
+    return SQLITE_OK;
   }
-  sqlite3VdbeAddOp3(v, OP_Insert, baseCur, regRec, regRowid);
-  if( !pParse->nested ){
-    sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
+  rc = db->xAuth(db->pAuthArg, code, zArg1, zArg2, zArg3, pParse->zAuthContext);
+  if( rc==SQLITE_DENY ){
+    sqlite3ErrorMsg(pParse, "not authorized");
+    pParse->rc = SQLITE_AUTH;
+  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
+    rc = SQLITE_DENY;
+    sqliteAuthBadReturnCode(pParse);
   }
-  sqlite3VdbeChangeP5(v, pik_flags);
+  return rc;
 }
 
 /*
-** Generate code that will open cursors for a table and for all
-** indices of that table.  The "baseCur" parameter is the cursor number used
-** for the table.  Indices are opened on subsequent cursors.
-**
-** Return the number of indices on the table.
+** Push an authorization context.  After this routine is called, the
+** zArg3 argument to authorization callbacks will be zContext until
+** popped.  Or if pParse==0, this routine is a no-op.
 */
-SQLITE_PRIVATE int sqlite3OpenTableAndIndices(
-  Parse *pParse,   /* Parsing context */
-  Table *pTab,     /* Table to be opened */
-  int baseCur,        /* Cursor number assigned to the table */
-  int op           /* OP_OpenRead or OP_OpenWrite */
+SQLITE_PRIVATE void sqlite3AuthContextPush(
+  Parse *pParse,
+  AuthContext *pContext, 
+  const char *zContext
 ){
-  int i;
-  int iDb;
-  Index *pIdx;
-  Vdbe *v;
+  assert( pParse );
+  pContext->pParse = pParse;
+  pContext->zAuthContext = pParse->zAuthContext;
+  pParse->zAuthContext = zContext;
+}
 
-  if( IsVirtual(pTab) ) return 0;
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-  v = sqlite3GetVdbe(pParse);
-  assert( v!=0 );
-  sqlite3OpenTable(pParse, baseCur, iDb, pTab, op);
-  for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
-    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
-    assert( pIdx->pSchema==pTab->pSchema );
-    sqlite3VdbeAddOp4(v, op, i+baseCur, pIdx->tnum, iDb,
-                      (char*)pKey, P4_KEYINFO_HANDOFF);
-    VdbeComment((v, "%s", pIdx->zName));
-  }
-  if( pParse->nTab<=baseCur+i ){
-    pParse->nTab = baseCur+i;
+/*
+** Pop an authorization context that was previously pushed
+** by sqlite3AuthContextPush
+*/
+SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext *pContext){
+  if( pContext->pParse ){
+    pContext->pParse->zAuthContext = pContext->zAuthContext;
+    pContext->pParse = 0;
   }
-  return i-1;
 }
 
+#endif /* SQLITE_OMIT_AUTHORIZATION */
 
-#ifdef SQLITE_TEST
+/************** End of auth.c ************************************************/
+/************** Begin file build.c *******************************************/
 /*
-** The following global variable is incremented whenever the
-** transfer optimization is used.  This is used for testing
-** purposes only - to make sure the transfer optimization really
-** is happening when it is suppose to.
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that are called by the SQLite parser
+** when syntax rules are reduced.  The routines in this file handle the
+** following kinds of SQL syntax:
+**
+**     CREATE TABLE
+**     DROP TABLE
+**     CREATE INDEX
+**     DROP INDEX
+**     creating ID lists
+**     BEGIN TRANSACTION
+**     COMMIT
+**     ROLLBACK
+**
+** $Id: build.c,v 1.557 2009/07/24 17:58:53 danielk1977 Exp $
 */
-SQLITE_API int sqlite3_xferopt_count;
-#endif /* SQLITE_TEST */
-
 
-#ifndef SQLITE_OMIT_XFER_OPT
 /*
-** Check to collation names to see if they are compatible.
+** This routine is called when a new SQL statement is beginning to
+** be parsed.  Initialize the pParse structure as needed.
 */
-static int xferCompatibleCollation(const char *z1, const char *z2){
-  if( z1==0 ){
-    return z2==0;
-  }
-  if( z2==0 ){
-    return 0;
-  }
-  return sqlite3StrICmp(z1, z2)==0;
+SQLITE_PRIVATE void sqlite3BeginParse(Parse *pParse, int explainFlag){
+  pParse->explain = (u8)explainFlag;
+  pParse->nVar = 0;
 }
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
+/*
+** The TableLock structure is only used by the sqlite3TableLock() and
+** codeTableLocks() functions.
+*/
+struct TableLock {
+  int iDb;             /* The database containing the table to be locked */
+  int iTab;            /* The root page of the table to be locked */
+  u8 isWriteLock;      /* True for write lock.  False for a read lock */
+  const char *zName;   /* Name of the table */
+};
 
 /*
-** Check to see if index pSrc is compatible as a source of data
-** for index pDest in an insert transfer optimization.  The rules
-** for a compatible index:
+** Record the fact that we want to lock a table at run-time.  
 **
-**    *   The index is over the same set of columns
-**    *   The same DESC and ASC markings occurs on all columns
-**    *   The same onError processing (OE_Abort, OE_Ignore, etc)
-**    *   The same collating sequence on each column
+** The table to be locked has root page iTab and is found in database iDb.
+** A read or a write lock can be taken depending on isWritelock.
+**
+** This routine just records the fact that the lock is desired.  The
+** code to make the lock occur is generated by a later call to
+** codeTableLocks() which occurs during sqlite3FinishCoding().
 */
-static int xferCompatibleIndex(Index *pDest, Index *pSrc){
+SQLITE_PRIVATE void sqlite3TableLock(
+  Parse *pParse,     /* Parsing context */
+  int iDb,           /* Index of the database containing the table to lock */
+  int iTab,          /* Root page number of the table to be locked */
+  u8 isWriteLock,    /* True for a write lock */
+  const char *zName  /* Name of the table to be locked */
+){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
   int i;
-  assert( pDest && pSrc );
-  assert( pDest->pTable!=pSrc->pTable );
-  if( pDest->nColumn!=pSrc->nColumn ){
-    return 0;   /* Different number of columns */
-  }
-  if( pDest->onError!=pSrc->onError ){
-    return 0;   /* Different conflict resolution strategies */
-  }
-  for(i=0; i<pSrc->nColumn; i++){
-    if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){
-      return 0;   /* Different columns indexed */
-    }
-    if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){
-      return 0;   /* Different sort orders */
-    }
-    if( pSrc->azColl[i]!=pDest->azColl[i] ){
-      return 0;   /* Different collating sequences */
+  int nBytes;
+  TableLock *p;
+  assert( iDb>=0 );
+
+  for(i=0; i<pToplevel->nTableLock; i++){
+    p = &pToplevel->aTableLock[i];
+    if( p->iDb==iDb && p->iTab==iTab ){
+      p->isWriteLock = (p->isWriteLock || isWriteLock);
+      return;
     }
   }
 
-  /* If no test above fails then the indices must be compatible */
-  return 1;
+  nBytes = sizeof(TableLock) * (pToplevel->nTableLock+1);
+  pToplevel->aTableLock =
+      sqlite3DbReallocOrFree(pToplevel->db, pToplevel->aTableLock, nBytes);
+  if( pToplevel->aTableLock ){
+    p = &pToplevel->aTableLock[pToplevel->nTableLock++];
+    p->iDb = iDb;
+    p->iTab = iTab;
+    p->isWriteLock = isWriteLock;
+    p->zName = zName;
+  }else{
+    pToplevel->nTableLock = 0;
+    pToplevel->db->mallocFailed = 1;
+  }
 }
 
 /*
-** Attempt the transfer optimization on INSERTs of the form
-**
-**     INSERT INTO tab1 SELECT * FROM tab2;
-**
-** This optimization is only attempted if
-**
-**    (1)  tab1 and tab2 have identical schemas including all the
-**         same indices and constraints
-**
-**    (2)  tab1 and tab2 are different tables
-**
-**    (3)  There must be no triggers on tab1
-**
-**    (4)  The result set of the SELECT statement is "*"
-**
-**    (5)  The SELECT statement has no WHERE, HAVING, ORDER BY, GROUP BY,
-**         or LIMIT clause.
-**
-**    (6)  The SELECT statement is a simple (not a compound) select that
-**         contains only tab2 in its FROM clause
-**
-** This method for implementing the INSERT transfers raw records from
-** tab2 over to tab1.  The columns are not decoded.  Raw records from
-** the indices of tab2 are transfered to tab1 as well.  In so doing,
-** the resulting tab1 has much less fragmentation.
-**
-** This routine returns TRUE if the optimization is attempted.  If any
-** of the conditions above fail so that the optimization should not
-** be attempted, then this routine returns FALSE.
+** Code an OP_TableLock instruction for each table locked by the
+** statement (configured by calls to sqlite3TableLock()).
 */
-static int xferOptimization(
-  Parse *pParse,        /* Parser context */
-  Table *pDest,         /* The table we are inserting into */
-  Select *pSelect,      /* A SELECT statement to use as the data source */
-  int onError,          /* How to handle constraint errors */
-  int iDbDest           /* The database of pDest */
-){
-  ExprList *pEList;                /* The result set of the SELECT */
-  Table *pSrc;                     /* The table in the FROM clause of SELECT */
-  Index *pSrcIdx, *pDestIdx;       /* Source and destination indices */
-  struct SrcList_item *pItem;      /* An element of pSelect->pSrc */
-  int i;                           /* Loop counter */
-  int iDbSrc;                      /* The database of pSrc */
-  int iSrc, iDest;                 /* Cursors from source and destination */
-  int addr1, addr2;                /* Loop addresses */
-  int emptyDestTest;               /* Address of test for empty pDest */
-  int emptySrcTest;                /* Address of test for empty pSrc */
-  Vdbe *v;                         /* The VDBE we are building */
-  KeyInfo *pKey;                   /* Key information for an index */
-  int regAutoinc;                  /* Memory register used by AUTOINC */
-  int destHasUniqueIdx = 0;        /* True if pDest has a UNIQUE index */
-  int regData, regRowid;           /* Registers holding data and rowid */
+static void codeTableLocks(Parse *pParse){
+  int i;
+  Vdbe *pVdbe; 
 
-  if( pSelect==0 ){
-    return 0;   /* Must be of the form  INSERT INTO ... SELECT ... */
-  }
-  if( pDest->pTrigger ){
-    return 0;   /* tab1 must not have triggers */
-  }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( pDest->isVirtual ){
-    return 0;   /* tab1 must not be a virtual table */
+  pVdbe = sqlite3GetVdbe(pParse);
+  assert( pVdbe!=0 ); /* sqlite3GetVdbe cannot fail: VDBE already allocated */
+
+  for(i=0; i<pParse->nTableLock; i++){
+    TableLock *p = &pParse->aTableLock[i];
+    int p1 = p->iDb;
+    sqlite3VdbeAddOp4(pVdbe, OP_TableLock, p1, p->iTab, p->isWriteLock,
+                      p->zName, P4_STATIC);
   }
+}
+#else
+  #define codeTableLocks(x)
 #endif
-  if( onError==OE_Default ){
-    onError = OE_Abort;
-  }
-  if( onError!=OE_Abort && onError!=OE_Rollback ){
-    return 0;   /* Cannot do OR REPLACE or OR IGNORE or OR FAIL */
-  }
-  assert(pSelect->pSrc);   /* allocated even if there is no FROM clause */
-  if( pSelect->pSrc->nSrc!=1 ){
-    return 0;   /* FROM clause must have exactly one term */
-  }
-  if( pSelect->pSrc->a[0].pSelect ){
-    return 0;   /* FROM clause cannot contain a subquery */
-  }
-  if( pSelect->pWhere ){
-    return 0;   /* SELECT may not have a WHERE clause */
-  }
-  if( pSelect->pOrderBy ){
-    return 0;   /* SELECT may not have an ORDER BY clause */
-  }
-  /* Do not need to test for a HAVING clause.  If HAVING is present but
-  ** there is no ORDER BY, we will get an error. */
-  if( pSelect->pGroupBy ){
-    return 0;   /* SELECT may not have a GROUP BY clause */
-  }
-  if( pSelect->pLimit ){
-    return 0;   /* SELECT may not have a LIMIT clause */
-  }
-  assert( pSelect->pOffset==0 );  /* Must be so if pLimit==0 */
-  if( pSelect->pPrior ){
-    return 0;   /* SELECT may not be a compound query */
-  }
-  if( pSelect->isDistinct ){
-    return 0;   /* SELECT may not be DISTINCT */
-  }
-  pEList = pSelect->pEList;
-  assert( pEList!=0 );
-  if( pEList->nExpr!=1 ){
-    return 0;   /* The result set must have exactly one column */
-  }
-  assert( pEList->a[0].pExpr );
-  if( pEList->a[0].pExpr->op!=TK_ALL ){
-    return 0;   /* The result set must be the special operator "*" */
-  }
 
-  /* At this point we have established that the statement is of the
-  ** correct syntactic form to participate in this optimization.  Now
-  ** we have to check the semantics.
+/*
+** This routine is called after a single SQL statement has been
+** parsed and a VDBE program to execute that statement has been
+** prepared.  This routine puts the finishing touches on the
+** VDBE program and resets the pParse structure for the next
+** parse.
+**
+** Note that if an error occurred, it might be the case that
+** no VDBE code was generated.
+*/
+SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
+  sqlite3 *db;
+  Vdbe *v;
+
+  db = pParse->db;
+  if( db->mallocFailed ) return;
+  if( pParse->nested ) return;
+  if( pParse->nErr ) return;
+
+  /* Begin by generating some termination code at the end of the
+  ** vdbe program
   */
-  pItem = pSelect->pSrc->a;
-  pSrc = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
-  if( pSrc==0 ){
-    return 0;   /* FROM clause does not contain a real table */
-  }
-  if( pSrc==pDest ){
-    return 0;   /* tab1 and tab2 may not be the same table */
-  }
+  v = sqlite3GetVdbe(pParse);
+  assert( !pParse->isMultiWrite 
+       || sqlite3VdbeAssertMayAbort(v, pParse->mayAbort));
+  if( v ){
+    sqlite3VdbeAddOp0(v, OP_Halt);
+
+    /* The cookie mask contains one bit for each database file open.
+    ** (Bit 0 is for main, bit 1 is for temp, and so forth.)  Bits are
+    ** set for each database that is used.  Generate code to start a
+    ** transaction on each used database and to verify the schema cookie
+    ** on each used database.
+    */
+    if( pParse->cookieGoto>0 ){
+      u32 mask;
+      int iDb;
+      sqlite3VdbeJumpHere(v, pParse->cookieGoto-1);
+      for(iDb=0, mask=1; iDb<db->nDb; mask<<=1, iDb++){
+        if( (mask & pParse->cookieMask)==0 ) continue;
+        sqlite3VdbeUsesBtree(v, iDb);
+        sqlite3VdbeAddOp2(v,OP_Transaction, iDb, (mask & pParse->writeMask)!=0);
+        if( db->init.busy==0 ){
+          sqlite3VdbeAddOp2(v,OP_VerifyCookie, iDb, pParse->cookieValue[iDb]);
+        }
+      }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( pSrc->isVirtual ){
-    return 0;   /* tab2 must not be a virtual table */
-  }
+      {
+        int i;
+        for(i=0; i<pParse->nVtabLock; i++){
+          char *vtab = (char *)sqlite3GetVTable(db, pParse->apVtabLock[i]);
+          sqlite3VdbeAddOp4(v, OP_VBegin, 0, 0, 0, vtab, P4_VTAB);
+        }
+        pParse->nVtabLock = 0;
+      }
 #endif
-  if( pSrc->pSelect ){
-    return 0;   /* tab2 may not be a view */
-  }
-  if( pDest->nCol!=pSrc->nCol ){
-    return 0;   /* Number of columns must be the same in tab1 and tab2 */
-  }
-  if( pDest->iPKey!=pSrc->iPKey ){
-    return 0;   /* Both tables must have the same INTEGER PRIMARY KEY */
-  }
-  for(i=0; i<pDest->nCol; i++){
-    if( pDest->aCol[i].affinity!=pSrc->aCol[i].affinity ){
-      return 0;    /* Affinity must be the same on all columns */
-    }
-    if( !xferCompatibleCollation(pDest->aCol[i].zColl, pSrc->aCol[i].zColl) ){
-      return 0;    /* Collating sequence must be the same on all columns */
-    }
-    if( pDest->aCol[i].notNull && !pSrc->aCol[i].notNull ){
-      return 0;    /* tab2 must be NOT NULL if tab1 is */
-    }
-  }
-  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
-    if( pDestIdx->onError!=OE_None ){
-      destHasUniqueIdx = 1;
-    }
-    for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
-      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
-    }
-    if( pSrcIdx==0 ){
-      return 0;    /* pDestIdx has no corresponding index in pSrc */
+
+      /* Once all the cookies have been verified and transactions opened, 
+      ** obtain the required table-locks. This is a no-op unless the 
+      ** shared-cache feature is enabled.
+      */
+      codeTableLocks(pParse);
+
+      /* Initialize any AUTOINCREMENT data structures required.
+      */
+      sqlite3AutoincrementBegin(pParse);
+
+      /* Finally, jump back to the beginning of the executable code. */
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->cookieGoto);
     }
   }
-#ifndef SQLITE_OMIT_CHECK
-  if( pDest->pCheck && !sqlite3ExprCompare(pSrc->pCheck, pDest->pCheck) ){
-    return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
-  }
-#endif
 
-  /* If we get this far, it means either:
-  **
-  **    *   We can always do the transfer if the table contains an
-  **        an integer primary key
-  **
-  **    *   We can conditionally do the transfer if the destination
-  **        table is empty.
+
+  /* Get the VDBE program ready for execution
   */
-#ifdef SQLITE_TEST
-  sqlite3_xferopt_count++;
+  if( v && ALWAYS(pParse->nErr==0) && !db->mallocFailed ){
+#ifdef SQLITE_DEBUG
+    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
+    sqlite3VdbeTrace(v, trace);
 #endif
-  iDbSrc = sqlite3SchemaToIndex(pParse->db, pSrc->pSchema);
-  v = sqlite3GetVdbe(pParse);
-  sqlite3CodeVerifySchema(pParse, iDbSrc);
-  iSrc = pParse->nTab++;
-  iDest = pParse->nTab++;
-  regAutoinc = autoIncBegin(pParse, iDbDest, pDest);
-  sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite);
-  if( (pDest->iPKey<0 && pDest->pIndex!=0) || destHasUniqueIdx ){
-    /* If tables do not have an INTEGER PRIMARY KEY and there
-    ** are indices to be copied and the destination is not empty,
-    ** we have to disallow the transfer optimization because the
-    ** the rowids might change which will mess up indexing.
-    **
-    ** Or if the destination has a UNIQUE index and is not empty,
-    ** we also disallow the transfer optimization because we cannot
-    ** insure that all entries in the union of DEST and SRC will be
-    ** unique.
-    */
-    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0);
-    emptyDestTest = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    sqlite3VdbeJumpHere(v, addr1);
-  }else{
-    emptyDestTest = 0;
-  }
-  sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead);
-  emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
-  regData = sqlite3GetTempReg(pParse);
-  regRowid = sqlite3GetTempReg(pParse);
-  if( pDest->iPKey>=0 ){
-    addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
-    addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid);
-    sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0,
-                      "PRIMARY KEY must be unique", P4_STATIC);
-    sqlite3VdbeJumpHere(v, addr2);
-    autoIncStep(pParse, regAutoinc, regRowid);
-  }else if( pDest->pIndex==0 ){
-    addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid);
-  }else{
-    addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
-    assert( pDest->autoInc==0 );
-  }
-  sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData);
-  sqlite3VdbeAddOp3(v, OP_Insert, iDest, regData, regRowid);
-  sqlite3VdbeChangeP5(v, OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND);
-  sqlite3VdbeChangeP4(v, -1, pDest->zName, 0);
-  sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1);
-  autoIncEnd(pParse, iDbDest, pDest, regAutoinc);
-  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
-    for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
-      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
-    }
-    assert( pSrcIdx );
-    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
-    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
-    pKey = sqlite3IndexKeyinfo(pParse, pSrcIdx);
-    sqlite3VdbeAddOp4(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc,
-                      (char*)pKey, P4_KEYINFO_HANDOFF);
-    VdbeComment((v, "%s", pSrcIdx->zName));
-    pKey = sqlite3IndexKeyinfo(pParse, pDestIdx);
-    sqlite3VdbeAddOp4(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest,
-                      (char*)pKey, P4_KEYINFO_HANDOFF);
-    VdbeComment((v, "%s", pDestIdx->zName));
-    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
-    sqlite3VdbeAddOp2(v, OP_RowKey, iSrc, regData);
-    sqlite3VdbeAddOp3(v, OP_IdxInsert, iDest, regData, 1);
-    sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1);
-    sqlite3VdbeJumpHere(v, addr1);
-  }
-  sqlite3VdbeJumpHere(v, emptySrcTest);
-  sqlite3ReleaseTempReg(pParse, regRowid);
-  sqlite3ReleaseTempReg(pParse, regData);
-  sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
-  sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
-  if( emptyDestTest ){
-    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0);
-    sqlite3VdbeJumpHere(v, emptyDestTest);
-    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
-    return 0;
-  }else{
-    return 1;
+    assert( pParse->iCacheLevel==0 );  /* Disables and re-enables match */
+    /* A minimum of one cursor is required if autoincrement is used
+    *  See ticket [a696379c1f08866] */
+    if( pParse->pAinc!=0 && pParse->nTab==0 ) pParse->nTab = 1;
+    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem,
+                         pParse->nTab, pParse->nMaxArg, pParse->explain,
+                         pParse->isMultiWrite && pParse->mayAbort);
+    pParse->rc = SQLITE_DONE;
+    pParse->colNamesSet = 0;
+  }else if( pParse->rc==SQLITE_OK ){
+    pParse->rc = SQLITE_ERROR;
   }
+  pParse->nTab = 0;
+  pParse->nMem = 0;
+  pParse->nSet = 0;
+  pParse->nVar = 0;
+  pParse->cookieMask = 0;
+  pParse->cookieGoto = 0;
 }
-#endif /* SQLITE_OMIT_XFER_OPT */
 
-/* Make sure "isView" gets undefined in case this file becomes part of
-** the amalgamation - so that subsequent files do not see isView as a
-** macro. */
-#undef isView
-
-/************** End of insert.c **********************************************/
-/************** Begin file legacy.c ******************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Run the parser and code generator recursively in order to generate
+** code for the SQL statement given onto the end of the pParse context
+** currently under construction.  When the parser is run recursively
+** this way, the final OP_Halt is not appended and other initialization
+** and finalization steps are omitted because those are handling by the
+** outermost parser.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Not everything is nestable.  This facility is designed to permit
+** INSERT, UPDATE, and DELETE operations against SQLITE_MASTER.  Use
+** care if you decide to try to use this routine for some other purposes.
+*/
+SQLITE_PRIVATE void sqlite3NestedParse(Parse *pParse, const char *zFormat, ...){
+  va_list ap;
+  char *zSql;
+  char *zErrMsg = 0;
+  sqlite3 *db = pParse->db;
+# define SAVE_SZ  (sizeof(Parse) - offsetof(Parse,nVar))
+  char saveBuf[SAVE_SZ];
+
+  if( pParse->nErr ) return;
+  assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
+  va_start(ap, zFormat);
+  zSql = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  if( zSql==0 ){
+    return;   /* A malloc must have failed */
+  }
+  pParse->nested++;
+  memcpy(saveBuf, &pParse->nVar, SAVE_SZ);
+  memset(&pParse->nVar, 0, SAVE_SZ);
+  sqlite3RunParser(pParse, zSql, &zErrMsg);
+  sqlite3DbFree(db, zErrMsg);
+  sqlite3DbFree(db, zSql);
+  memcpy(&pParse->nVar, saveBuf, SAVE_SZ);
+  pParse->nested--;
+}
+
+/*
+** Locate the in-memory structure that describes a particular database
+** table given the name of that table and (optionally) the name of the
+** database containing the table.  Return NULL if not found.
 **
-*************************************************************************
-** Main file for the SQLite library.  The routines in this file
-** implement the programmer interface to the library.  Routines in
-** other files are for internal use by SQLite and should not be
-** accessed by users of the library.
+** If zDatabase is 0, all databases are searched for the table and the
+** first matching table is returned.  (No checking for duplicate table
+** names is done.)  The search order is TEMP first, then MAIN, then any
+** auxiliary databases added using the ATTACH command.
 **
-** $Id: legacy.c,v 1.24 2008/03/21 18:01:14 drh Exp $
+** See also sqlite3LocateTable().
 */
-
+SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
+  Table *p = 0;
+  int i;
+  int nName;
+  assert( zName!=0 );
+  nName = sqlite3Strlen30(zName);
+  for(i=OMIT_TEMPDB; i<db->nDb; i++){
+    int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
+    if( zDatabase!=0 && sqlite3StrICmp(zDatabase, db->aDb[j].zName) ) continue;
+    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName, nName);
+    if( p ) break;
+  }
+  return p;
+}
 
 /*
-** Execute SQL code.  Return one of the SQLITE_ success/failure
-** codes.  Also write an error message into memory obtained from
-** malloc() and make *pzErrMsg point to that message.
+** Locate the in-memory structure that describes a particular database
+** table given the name of that table and (optionally) the name of the
+** database containing the table.  Return NULL if not found.  Also leave an
+** error message in pParse->zErrMsg.
 **
-** If the SQL is a query, then for each row in the query result
-** the xCallback() function is called.  pArg becomes the first
-** argument to xCallback().  If xCallback=NULL then no callback
-** is invoked, even for queries.
+** The difference between this routine and sqlite3FindTable() is that this
+** routine leaves an error message in pParse->zErrMsg where
+** sqlite3FindTable() does not.
 */
-SQLITE_API int sqlite3_exec(
-  sqlite3 *db,                /* The database on which the SQL executes */
-  const char *zSql,           /* The SQL to be executed */
-  sqlite3_callback xCallback, /* Invoke this callback routine */
-  void *pArg,                 /* First argument to xCallback() */
-  char **pzErrMsg             /* Write error messages here */
+SQLITE_PRIVATE Table *sqlite3LocateTable(
+  Parse *pParse,         /* context in which to report errors */
+  int isView,            /* True if looking for a VIEW rather than a TABLE */
+  const char *zName,     /* Name of the table we are looking for */
+  const char *zDbase     /* Name of the database.  Might be NULL */
 ){
-  int rc = SQLITE_OK;
-  const char *zLeftover;
-  sqlite3_stmt *pStmt = 0;
-  char **azCols = 0;
+  Table *p;
 
-  int nRetry = 0;
-  int nCallback;
+  /* Read the database schema. If an error occurs, leave an error message
+  ** and code in pParse and return NULL. */
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    return 0;
+  }
 
-  if( zSql==0 ) return SQLITE_OK;
+  p = sqlite3FindTable(pParse->db, zName, zDbase);
+  if( p==0 ){
+    const char *zMsg = isView ? "no such view" : "no such table";
+    if( zDbase ){
+      sqlite3ErrorMsg(pParse, "%s: %s.%s", zMsg, zDbase, zName);
+    }else{
+      sqlite3ErrorMsg(pParse, "%s: %s", zMsg, zName);
+    }
+    pParse->checkSchema = 1;
+  }
+  return p;
+}
 
-  sqlite3_mutex_enter(db->mutex);
-  while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
-    int nCol;
-    char **azVals = 0;
+/*
+** Locate the in-memory structure that describes 
+** a particular index given the name of that index
+** and the name of the database that contains the index.
+** Return NULL if not found.
+**
+** If zDatabase is 0, all databases are searched for the
+** table and the first matching index is returned.  (No checking
+** for duplicate index names is done.)  The search order is
+** TEMP first, then MAIN, then any auxiliary databases added
+** using the ATTACH command.
+*/
+SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const char *zDb){
+  Index *p = 0;
+  int i;
+  int nName = sqlite3Strlen30(zName);
+  for(i=OMIT_TEMPDB; i<db->nDb; i++){
+    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
+    Schema *pSchema = db->aDb[j].pSchema;
+    assert( pSchema );
+    if( zDb && sqlite3StrICmp(zDb, db->aDb[j].zName) ) continue;
+    p = sqlite3HashFind(&pSchema->idxHash, zName, nName);
+    if( p ) break;
+  }
+  return p;
+}
 
-    pStmt = 0;
-    rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
-    assert( rc==SQLITE_OK || pStmt==0 );
-    if( rc!=SQLITE_OK ){
-      continue;
-    }
-    if( !pStmt ){
-      /* this happens for a comment or white-space */
-      zSql = zLeftover;
-      continue;
-    }
+/*
+** Reclaim the memory used by an index
+*/
+static void freeIndex(Index *p){
+  sqlite3 *db = p->pTable->dbMem;
+#ifndef SQLITE_OMIT_ANALYZE
+  sqlite3DeleteIndexSamples(p);
+#endif
+  sqlite3DbFree(db, p->zColAff);
+  sqlite3DbFree(db, p);
+}
 
-    nCallback = 0;
-    nCol = sqlite3_column_count(pStmt);
+/*
+** Remove the given index from the index hash table, and free
+** its memory structures.
+**
+** The index is removed from the database hash tables but
+** it is not unlinked from the Table that it indexes.
+** Unlinking from the Table must be done by the calling function.
+*/
+static void sqlite3DeleteIndex(Index *p){
+  Index *pOld;
+  const char *zName = p->zName;
 
-    while( 1 ){
-      int i;
-      rc = sqlite3_step(pStmt);
+  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName,
+                           sqlite3Strlen30(zName), 0);
+  assert( pOld==0 || pOld==p );
+  freeIndex(p);
+}
 
-      /* Invoke the callback function if required */
-      if( xCallback && (SQLITE_ROW==rc || 
-          (SQLITE_DONE==rc && !nCallback && db->flags&SQLITE_NullCallback)) ){
-        if( 0==nCallback ){
-          if( azCols==0 ){
-            azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1);
-            if( azCols==0 ){
-              goto exec_out;
-            }
-          }
-          for(i=0; i<nCol; i++){
-            azCols[i] = (char *)sqlite3_column_name(pStmt, i);
-            if( !azCols[i] ){
-              db->mallocFailed = 1;
-              goto exec_out;
-            }
-          }
-          nCallback++;
-        }
-        if( rc==SQLITE_ROW ){
-          azVals = &azCols[nCol];
-          for(i=0; i<nCol; i++){
-            azVals[i] = (char *)sqlite3_column_text(pStmt, i);
-            if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){
-              db->mallocFailed = 1;
-              goto exec_out;
-            }
-          }
-        }
-        if( xCallback(pArg, nCol, azVals, azCols) ){
-          rc = SQLITE_ABORT;
-          goto exec_out;
-        }
-      }
+/*
+** For the index called zIdxName which is found in the database iDb,
+** unlike that index from its Table then remove the index from
+** the index hash table and free all memory structures associated
+** with the index.
+*/
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
+  Index *pIndex;
+  int len;
+  Hash *pHash = &db->aDb[iDb].pSchema->idxHash;
 
-      if( rc!=SQLITE_ROW ){
-        rc = sqlite3_finalize(pStmt);
-        pStmt = 0;
-        if( rc!=SQLITE_SCHEMA ){
-          nRetry = 0;
-          zSql = zLeftover;
-          while( isspace((unsigned char)zSql[0]) ) zSql++;
-        }
-        break;
+  len = sqlite3Strlen30(zIdxName);
+  pIndex = sqlite3HashInsert(pHash, zIdxName, len, 0);
+  if( pIndex ){
+    if( pIndex->pTable->pIndex==pIndex ){
+      pIndex->pTable->pIndex = pIndex->pNext;
+    }else{
+      Index *p;
+      /* Justification of ALWAYS();  The index must be on the list of
+      ** indices. */
+      p = pIndex->pTable->pIndex;
+      while( ALWAYS(p) && p->pNext!=pIndex ){ p = p->pNext; }
+      if( ALWAYS(p && p->pNext==pIndex) ){
+        p->pNext = pIndex->pNext;
       }
     }
-
-    sqlite3_free(azCols);
-    azCols = 0;
+    freeIndex(pIndex);
   }
+  db->flags |= SQLITE_InternChanges;
+}
 
-exec_out:
-  if( pStmt ) sqlite3_finalize(pStmt);
-  if( azCols ) sqlite3_free(azCols);
+/*
+** Erase all schema information from the in-memory hash tables of
+** a single database.  This routine is called to reclaim memory
+** before the database closes.  It is also called during a rollback
+** if there were schema changes during the transaction or if a
+** schema-cookie mismatch occurs.
+**
+** If iDb==0 then reset the internal schema tables for all database
+** files.  If iDb>=1 then reset the internal schema for only the
+** single file indicated.
+*/
+SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
+  int i, j;
+  assert( iDb>=0 && iDb<db->nDb );
 
-  rc = sqlite3ApiExit(db, rc);
-  if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){
-    int nErrMsg = 1 + strlen(sqlite3_errmsg(db));
-    *pzErrMsg = sqlite3_malloc(nErrMsg);
-    if( *pzErrMsg ){
-      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
+  if( iDb==0 ){
+    sqlite3BtreeEnterAll(db);
+  }
+  for(i=iDb; i<db->nDb; i++){
+    Db *pDb = &db->aDb[i];
+    if( pDb->pSchema ){
+      assert(i==1 || (pDb->pBt && sqlite3BtreeHoldsMutex(pDb->pBt)));
+      sqlite3SchemaFree(pDb->pSchema);
     }
-  }else if( pzErrMsg ){
-    *pzErrMsg = 0;
+    if( iDb>0 ) return;
   }
+  assert( iDb==0 );
+  db->flags &= ~SQLITE_InternChanges;
+  sqlite3VtabUnlockList(db);
+  sqlite3BtreeLeaveAll(db);
 
-  assert( (rc&db->errMask)==rc );
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
+  /* If one or more of the auxiliary database files has been closed,
+  ** then remove them from the auxiliary database list.  We take the
+  ** opportunity to do this here since we have just deleted all of the
+  ** schema hash tables and therefore do not have to make any changes
+  ** to any of those tables.
+  */
+  for(i=j=2; i<db->nDb; i++){
+    struct Db *pDb = &db->aDb[i];
+    if( pDb->pBt==0 ){
+      sqlite3DbFree(db, pDb->zName);
+      pDb->zName = 0;
+      continue;
+    }
+    if( j<i ){
+      db->aDb[j] = db->aDb[i];
+    }
+    j++;
+  }
+  memset(&db->aDb[j], 0, (db->nDb-j)*sizeof(db->aDb[j]));
+  db->nDb = j;
+  if( db->nDb<=2 && db->aDb!=db->aDbStatic ){
+    memcpy(db->aDbStatic, db->aDb, 2*sizeof(db->aDb[0]));
+    sqlite3DbFree(db, db->aDb);
+    db->aDb = db->aDbStatic;
+  }
 }
 
-/************** End of legacy.c **********************************************/
-/************** Begin file loadext.c *****************************************/
 /*
-** 2006 June 7
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains code used to dynamically load extensions into
-** the SQLite library.
+** This routine is called when a commit occurs.
 */
+SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3 *db){
+  db->flags &= ~SQLITE_InternChanges;
+}
 
-#ifndef SQLITE_CORE
-  #define SQLITE_CORE 1  /* Disable the API redefinition in sqlite3ext.h */
-#endif
-/************** Include sqlite3ext.h in the middle of loadext.c **************/
-/************** Begin file sqlite3ext.h **************************************/
 /*
-** 2006 June 7
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This header file defines the SQLite interface for use by
-** shared libraries that want to be imported as extensions into
-** an SQLite instance.  Shared libraries that intend to be loaded
-** as extensions by SQLite should #include this file instead of 
-** sqlite3.h.
-**
-** @(#) $Id: sqlite3ext.h,v 1.21 2008/03/19 21:45:51 drh Exp $
+** Clear the column names from a table or view.
 */
-#ifndef _SQLITE3EXT_H_
-#define _SQLITE3EXT_H_
-
-typedef struct sqlite3_api_routines sqlite3_api_routines;
+static void sqliteResetColumnNames(Table *pTable){
+  int i;
+  Column *pCol;
+  sqlite3 *db = pTable->dbMem;
+  testcase( db==0 );
+  assert( pTable!=0 );
+  if( (pCol = pTable->aCol)!=0 ){
+    for(i=0; i<pTable->nCol; i++, pCol++){
+      sqlite3DbFree(db, pCol->zName);
+      sqlite3ExprDelete(db, pCol->pDflt);
+      sqlite3DbFree(db, pCol->zDflt);
+      sqlite3DbFree(db, pCol->zType);
+      sqlite3DbFree(db, pCol->zColl);
+    }
+    sqlite3DbFree(db, pTable->aCol);
+  }
+  pTable->aCol = 0;
+  pTable->nCol = 0;
+}
 
 /*
-** The following structure holds pointers to all of the SQLite API
-** routines.
+** Remove the memory data structures associated with the given
+** Table.  No changes are made to disk by this routine.
 **
-** WARNING:  In order to maintain backwards compatibility, add new
-** interfaces to the end of this structure only.  If you insert new
-** interfaces in the middle of this structure, then older different
-** versions of SQLite will not be able to load each others' shared
-** libraries!
+** This routine just deletes the data structure.  It does not unlink
+** the table data structure from the hash table.  But it does destroy
+** memory structures of the indices and foreign keys associated with 
+** the table.
 */
-struct sqlite3_api_routines {
-  void * (*aggregate_context)(sqlite3_context*,int nBytes);
-  int  (*aggregate_count)(sqlite3_context*);
-  int  (*bind_blob)(sqlite3_stmt*,int,const void*,int n,void(*)(void*));
-  int  (*bind_double)(sqlite3_stmt*,int,double);
-  int  (*bind_int)(sqlite3_stmt*,int,int);
-  int  (*bind_int64)(sqlite3_stmt*,int,sqlite_int64);
-  int  (*bind_null)(sqlite3_stmt*,int);
-  int  (*bind_parameter_count)(sqlite3_stmt*);
-  int  (*bind_parameter_index)(sqlite3_stmt*,const char*zName);
-  const char * (*bind_parameter_name)(sqlite3_stmt*,int);
-  int  (*bind_text)(sqlite3_stmt*,int,const char*,int n,void(*)(void*));
-  int  (*bind_text16)(sqlite3_stmt*,int,const void*,int,void(*)(void*));
-  int  (*bind_value)(sqlite3_stmt*,int,const sqlite3_value*);
-  int  (*busy_handler)(sqlite3*,int(*)(void*,int),void*);
-  int  (*busy_timeout)(sqlite3*,int ms);
-  int  (*changes)(sqlite3*);
-  int  (*close)(sqlite3*);
-  int  (*collation_needed)(sqlite3*,void*,void(*)(void*,sqlite3*,int eTextRep,const char*));
-  int  (*collation_needed16)(sqlite3*,void*,void(*)(void*,sqlite3*,int eTextRep,const void*));
-  const void * (*column_blob)(sqlite3_stmt*,int iCol);
-  int  (*column_bytes)(sqlite3_stmt*,int iCol);
-  int  (*column_bytes16)(sqlite3_stmt*,int iCol);
-  int  (*column_count)(sqlite3_stmt*pStmt);
-  const char * (*column_database_name)(sqlite3_stmt*,int);
-  const void * (*column_database_name16)(sqlite3_stmt*,int);
-  const char * (*column_decltype)(sqlite3_stmt*,int i);
-  const void * (*column_decltype16)(sqlite3_stmt*,int);
-  double  (*column_double)(sqlite3_stmt*,int iCol);
-  int  (*column_int)(sqlite3_stmt*,int iCol);
-  sqlite_int64  (*column_int64)(sqlite3_stmt*,int iCol);
-  const char * (*column_name)(sqlite3_stmt*,int);
-  const void * (*column_name16)(sqlite3_stmt*,int);
-  const char * (*column_origin_name)(sqlite3_stmt*,int);
-  const void * (*column_origin_name16)(sqlite3_stmt*,int);
-  const char * (*column_table_name)(sqlite3_stmt*,int);
-  const void * (*column_table_name16)(sqlite3_stmt*,int);
-  const unsigned char * (*column_text)(sqlite3_stmt*,int iCol);
-  const void * (*column_text16)(sqlite3_stmt*,int iCol);
-  int  (*column_type)(sqlite3_stmt*,int iCol);
-  sqlite3_value* (*column_value)(sqlite3_stmt*,int iCol);
-  void * (*commit_hook)(sqlite3*,int(*)(void*),void*);
-  int  (*complete)(const char*sql);
-  int  (*complete16)(const void*sql);
-  int  (*create_collation)(sqlite3*,const char*,int,void*,int(*)(void*,int,const void*,int,const void*));
-  int  (*create_collation16)(sqlite3*,const char*,int,void*,int(*)(void*,int,const void*,int,const void*));
-  int  (*create_function)(sqlite3*,const char*,int,int,void*,void (*xFunc)(sqlite3_context*,int,sqlite3_value**),void (*xStep)(sqlite3_context*,int,sqlite3_value**),void (*xFinal)(sqlite3_context*));
-  int  (*create_function16)(sqlite3*,const void*,int,int,void*,void (*xFunc)(sqlite3_context*,int,sqlite3_value**),void (*xStep)(sqlite3_context*,int,sqlite3_value**),void (*xFinal)(sqlite3_context*));
-  int (*create_module)(sqlite3*,const char*,const sqlite3_module*,void*);
-  int  (*data_count)(sqlite3_stmt*pStmt);
-  sqlite3 * (*db_handle)(sqlite3_stmt*);
-  int (*declare_vtab)(sqlite3*,const char*);
-  int  (*enable_shared_cache)(int);
-  int  (*errcode)(sqlite3*db);
-  const char * (*errmsg)(sqlite3*);
-  const void * (*errmsg16)(sqlite3*);
-  int  (*exec)(sqlite3*,const char*,sqlite3_callback,void*,char**);
-  int  (*expired)(sqlite3_stmt*);
-  int  (*finalize)(sqlite3_stmt*pStmt);
-  void  (*free)(void*);
-  void  (*free_table)(char**result);
-  int  (*get_autocommit)(sqlite3*);
-  void * (*get_auxdata)(sqlite3_context*,int);
-  int  (*get_table)(sqlite3*,const char*,char***,int*,int*,char**);
-  int  (*global_recover)(void);
-  void  (*interruptx)(sqlite3*);
-  sqlite_int64  (*last_insert_rowid)(sqlite3*);
-  const char * (*libversion)(void);
-  int  (*libversion_number)(void);
-  void *(*malloc)(int);
-  char * (*mprintf)(const char*,...);
-  int  (*open)(const char*,sqlite3**);
-  int  (*open16)(const void*,sqlite3**);
-  int  (*prepare)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
-  int  (*prepare16)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
-  void * (*profile)(sqlite3*,void(*)(void*,const char*,sqlite_uint64),void*);
-  void  (*progress_handler)(sqlite3*,int,int(*)(void*),void*);
-  void *(*realloc)(void*,int);
-  int  (*reset)(sqlite3_stmt*pStmt);
-  void  (*result_blob)(sqlite3_context*,const void*,int,void(*)(void*));
-  void  (*result_double)(sqlite3_context*,double);
-  void  (*result_error)(sqlite3_context*,const char*,int);
-  void  (*result_error16)(sqlite3_context*,const void*,int);
-  void  (*result_int)(sqlite3_context*,int);
-  void  (*result_int64)(sqlite3_context*,sqlite_int64);
-  void  (*result_null)(sqlite3_context*);
-  void  (*result_text)(sqlite3_context*,const char*,int,void(*)(void*));
-  void  (*result_text16)(sqlite3_context*,const void*,int,void(*)(void*));
-  void  (*result_text16be)(sqlite3_context*,const void*,int,void(*)(void*));
-  void  (*result_text16le)(sqlite3_context*,const void*,int,void(*)(void*));
-  void  (*result_value)(sqlite3_context*,sqlite3_value*);
-  void * (*rollback_hook)(sqlite3*,void(*)(void*),void*);
-  int  (*set_authorizer)(sqlite3*,int(*)(void*,int,const char*,const char*,const char*,const char*),void*);
-  void  (*set_auxdata)(sqlite3_context*,int,void*,void (*)(void*));
-  char * (*snprintf)(int,char*,const char*,...);
-  int  (*step)(sqlite3_stmt*);
-  int  (*table_column_metadata)(sqlite3*,const char*,const char*,const char*,char const**,char const**,int*,int*,int*);
-  void  (*thread_cleanup)(void);
-  int  (*total_changes)(sqlite3*);
-  void * (*trace)(sqlite3*,void(*xTrace)(void*,const char*),void*);
-  int  (*transfer_bindings)(sqlite3_stmt*,sqlite3_stmt*);
-  void * (*update_hook)(sqlite3*,void(*)(void*,int ,char const*,char const*,sqlite_int64),void*);
-  void * (*user_data)(sqlite3_context*);
-  const void * (*value_blob)(sqlite3_value*);
-  int  (*value_bytes)(sqlite3_value*);
-  int  (*value_bytes16)(sqlite3_value*);
-  double  (*value_double)(sqlite3_value*);
-  int  (*value_int)(sqlite3_value*);
-  sqlite_int64  (*value_int64)(sqlite3_value*);
-  int  (*value_numeric_type)(sqlite3_value*);
-  const unsigned char * (*value_text)(sqlite3_value*);
-  const void * (*value_text16)(sqlite3_value*);
-  const void * (*value_text16be)(sqlite3_value*);
-  const void * (*value_text16le)(sqlite3_value*);
-  int  (*value_type)(sqlite3_value*);
-  char *(*vmprintf)(const char*,va_list);
-  /* Added ??? */
-  int (*overload_function)(sqlite3*, const char *zFuncName, int nArg);
-  /* Added by 3.3.13 */
-  int (*prepare_v2)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
-  int (*prepare16_v2)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
-  int (*clear_bindings)(sqlite3_stmt*);
-  /* Added by 3.4.1 */
-  int (*create_module_v2)(sqlite3*,const char*,const sqlite3_module*,void*,void (*xDestroy)(void *));
-  /* Added by 3.5.0 */
-  int (*bind_zeroblob)(sqlite3_stmt*,int,int);
-  int (*blob_bytes)(sqlite3_blob*);
-  int (*blob_close)(sqlite3_blob*);
-  int (*blob_open)(sqlite3*,const char*,const char*,const char*,sqlite3_int64,int,sqlite3_blob**);
-  int (*blob_read)(sqlite3_blob*,void*,int,int);
-  int (*blob_write)(sqlite3_blob*,const void*,int,int);
-  int (*create_collation_v2)(sqlite3*,const char*,int,void*,int(*)(void*,int,const void*,int,const void*),void(*)(void*));
-  int (*file_control)(sqlite3*,const char*,int,void*);
-  sqlite3_int64 (*memory_highwater)(int);
-  sqlite3_int64 (*memory_used)(void);
-  sqlite3_mutex *(*mutex_alloc)(int);
-  void (*mutex_enter)(sqlite3_mutex*);
-  void (*mutex_free)(sqlite3_mutex*);
-  void (*mutex_leave)(sqlite3_mutex*);
-  int (*mutex_try)(sqlite3_mutex*);
-  int (*open_v2)(const char*,sqlite3**,int,const char*);
-  int (*release_memory)(int);
-  void (*result_error_nomem)(sqlite3_context*);
-  void (*result_error_toobig)(sqlite3_context*);
-  int (*sleep)(int);
-  void (*soft_heap_limit)(int);
-  sqlite3_vfs *(*vfs_find)(const char*);
-  int (*vfs_register)(sqlite3_vfs*,int);
-  int (*vfs_unregister)(sqlite3_vfs*);
-  int (*xthreadsafe)(void);
-  void (*result_zeroblob)(sqlite3_context*,int);
-  void (*result_error_code)(sqlite3_context*,int);
-  int (*test_control)(int, ...);
-  void (*randomness)(int,void*);
-  sqlite3 *(*context_db_handle)(sqlite3_context*);
-};
+SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
+  Index *pIndex, *pNext;
+  sqlite3 *db;
+
+  if( pTable==0 ) return;
+  db = pTable->dbMem;
+  testcase( db==0 );
+
+  /* Do not delete the table until the reference count reaches zero. */
+  pTable->nRef--;
+  if( pTable->nRef>0 ){
+    return;
+  }
+  assert( pTable->nRef==0 );
+
+  /* Delete all indices associated with this table
+  */
+  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
+    pNext = pIndex->pNext;
+    assert( pIndex->pSchema==pTable->pSchema );
+    sqlite3DeleteIndex(pIndex);
+  }
+
+  /* Delete any foreign keys attached to this table. */
+  sqlite3FkDelete(pTable);
+
+  /* Delete the Table structure itself.
+  */
+  sqliteResetColumnNames(pTable);
+  sqlite3DbFree(db, pTable->zName);
+  sqlite3DbFree(db, pTable->zColAff);
+  sqlite3SelectDelete(db, pTable->pSelect);
+#ifndef SQLITE_OMIT_CHECK
+  sqlite3ExprDelete(db, pTable->pCheck);
+#endif
+  sqlite3VtabClear(pTable);
+  sqlite3DbFree(db, pTable);
+}
 
 /*
-** The following macros redefine the API routines so that they are
-** redirected throught the global sqlite3_api structure.
+** Unlink the given table from the hash tables and the delete the
+** table structure with all its indices and foreign keys.
+*/
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3 *db, int iDb, const char *zTabName){
+  Table *p;
+  Db *pDb;
+
+  assert( db!=0 );
+  assert( iDb>=0 && iDb<db->nDb );
+  assert( zTabName && zTabName[0] );
+  pDb = &db->aDb[iDb];
+  p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName,
+                        sqlite3Strlen30(zTabName),0);
+  sqlite3DeleteTable(p);
+  db->flags |= SQLITE_InternChanges;
+}
+
+/*
+** Given a token, return a string that consists of the text of that
+** token.  Space to hold the returned string
+** is obtained from sqliteMalloc() and must be freed by the calling
+** function.
 **
-** This header file is also used by the loadext.c source file
-** (part of the main SQLite library - not an extension) so that
-** it can get access to the sqlite3_api_routines structure
-** definition.  But the main library does not want to redefine
-** the API.  So the redefinition macros are only valid if the
-** SQLITE_CORE macros is undefined.
+** Any quotation marks (ex:  "name", 'name', [name], or `name`) that
+** surround the body of the token are removed.
+**
+** Tokens are often just pointers into the original SQL text and so
+** are not \000 terminated and are not persistent.  The returned string
+** is \000 terminated and is persistent.
 */
-#ifndef SQLITE_CORE
-#define sqlite3_aggregate_context      sqlite3_api->aggregate_context
-#define sqlite3_aggregate_count        sqlite3_api->aggregate_count
-#define sqlite3_bind_blob              sqlite3_api->bind_blob
-#define sqlite3_bind_double            sqlite3_api->bind_double
-#define sqlite3_bind_int               sqlite3_api->bind_int
-#define sqlite3_bind_int64             sqlite3_api->bind_int64
-#define sqlite3_bind_null              sqlite3_api->bind_null
-#define sqlite3_bind_parameter_count   sqlite3_api->bind_parameter_count
-#define sqlite3_bind_parameter_index   sqlite3_api->bind_parameter_index
-#define sqlite3_bind_parameter_name    sqlite3_api->bind_parameter_name
-#define sqlite3_bind_text              sqlite3_api->bind_text
-#define sqlite3_bind_text16            sqlite3_api->bind_text16
-#define sqlite3_bind_value             sqlite3_api->bind_value
-#define sqlite3_busy_handler           sqlite3_api->busy_handler
-#define sqlite3_busy_timeout           sqlite3_api->busy_timeout
-#define sqlite3_changes                sqlite3_api->changes
-#define sqlite3_close                  sqlite3_api->close
-#define sqlite3_collation_needed       sqlite3_api->collation_needed
-#define sqlite3_collation_needed16     sqlite3_api->collation_needed16
-#define sqlite3_column_blob            sqlite3_api->column_blob
-#define sqlite3_column_bytes           sqlite3_api->column_bytes
-#define sqlite3_column_bytes16         sqlite3_api->column_bytes16
-#define sqlite3_column_count           sqlite3_api->column_count
-#define sqlite3_column_database_name   sqlite3_api->column_database_name
-#define sqlite3_column_database_name16 sqlite3_api->column_database_name16
-#define sqlite3_column_decltype        sqlite3_api->column_decltype
-#define sqlite3_column_decltype16      sqlite3_api->column_decltype16
-#define sqlite3_column_double          sqlite3_api->column_double
-#define sqlite3_column_int             sqlite3_api->column_int
-#define sqlite3_column_int64           sqlite3_api->column_int64
-#define sqlite3_column_name            sqlite3_api->column_name
-#define sqlite3_column_name16          sqlite3_api->column_name16
-#define sqlite3_column_origin_name     sqlite3_api->column_origin_name
-#define sqlite3_column_origin_name16   sqlite3_api->column_origin_name16
-#define sqlite3_column_table_name      sqlite3_api->column_table_name
-#define sqlite3_column_table_name16    sqlite3_api->column_table_name16
-#define sqlite3_column_text            sqlite3_api->column_text
-#define sqlite3_column_text16          sqlite3_api->column_text16
-#define sqlite3_column_type            sqlite3_api->column_type
-#define sqlite3_column_value           sqlite3_api->column_value
-#define sqlite3_commit_hook            sqlite3_api->commit_hook
-#define sqlite3_complete               sqlite3_api->complete
-#define sqlite3_complete16             sqlite3_api->complete16
-#define sqlite3_create_collation       sqlite3_api->create_collation
-#define sqlite3_create_collation16     sqlite3_api->create_collation16
-#define sqlite3_create_function        sqlite3_api->create_function
-#define sqlite3_create_function16      sqlite3_api->create_function16
-#define sqlite3_create_module          sqlite3_api->create_module
-#define sqlite3_create_module_v2       sqlite3_api->create_module_v2
-#define sqlite3_data_count             sqlite3_api->data_count
-#define sqlite3_db_handle              sqlite3_api->db_handle
-#define sqlite3_declare_vtab           sqlite3_api->declare_vtab
-#define sqlite3_enable_shared_cache    sqlite3_api->enable_shared_cache
-#define sqlite3_errcode                sqlite3_api->errcode
-#define sqlite3_errmsg                 sqlite3_api->errmsg
-#define sqlite3_errmsg16               sqlite3_api->errmsg16
-#define sqlite3_exec                   sqlite3_api->exec
-#define sqlite3_expired                sqlite3_api->expired
-#define sqlite3_finalize               sqlite3_api->finalize
-#define sqlite3_free                   sqlite3_api->free
-#define sqlite3_free_table             sqlite3_api->free_table
-#define sqlite3_get_autocommit         sqlite3_api->get_autocommit
-#define sqlite3_get_auxdata            sqlite3_api->get_auxdata
-#define sqlite3_get_table              sqlite3_api->get_table
-#define sqlite3_global_recover         sqlite3_api->global_recover
-#define sqlite3_interrupt              sqlite3_api->interruptx
-#define sqlite3_last_insert_rowid      sqlite3_api->last_insert_rowid
-#define sqlite3_libversion             sqlite3_api->libversion
-#define sqlite3_libversion_number      sqlite3_api->libversion_number
-#define sqlite3_malloc                 sqlite3_api->malloc
-#define sqlite3_mprintf                sqlite3_api->mprintf
-#define sqlite3_open                   sqlite3_api->open
-#define sqlite3_open16                 sqlite3_api->open16
-#define sqlite3_prepare                sqlite3_api->prepare
-#define sqlite3_prepare16              sqlite3_api->prepare16
-#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
-#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
-#define sqlite3_profile                sqlite3_api->profile
-#define sqlite3_progress_handler       sqlite3_api->progress_handler
-#define sqlite3_realloc                sqlite3_api->realloc
-#define sqlite3_reset                  sqlite3_api->reset
-#define sqlite3_result_blob            sqlite3_api->result_blob
-#define sqlite3_result_double          sqlite3_api->result_double
-#define sqlite3_result_error           sqlite3_api->result_error
-#define sqlite3_result_error16         sqlite3_api->result_error16
-#define sqlite3_result_int             sqlite3_api->result_int
-#define sqlite3_result_int64           sqlite3_api->result_int64
-#define sqlite3_result_null            sqlite3_api->result_null
-#define sqlite3_result_text            sqlite3_api->result_text
-#define sqlite3_result_text16          sqlite3_api->result_text16
-#define sqlite3_result_text16be        sqlite3_api->result_text16be
-#define sqlite3_result_text16le        sqlite3_api->result_text16le
-#define sqlite3_result_value           sqlite3_api->result_value
-#define sqlite3_rollback_hook          sqlite3_api->rollback_hook
-#define sqlite3_set_authorizer         sqlite3_api->set_authorizer
-#define sqlite3_set_auxdata            sqlite3_api->set_auxdata
-#define sqlite3_snprintf               sqlite3_api->snprintf
-#define sqlite3_step                   sqlite3_api->step
-#define sqlite3_table_column_metadata  sqlite3_api->table_column_metadata
-#define sqlite3_thread_cleanup         sqlite3_api->thread_cleanup
-#define sqlite3_total_changes          sqlite3_api->total_changes
-#define sqlite3_trace                  sqlite3_api->trace
-#define sqlite3_transfer_bindings      sqlite3_api->transfer_bindings
-#define sqlite3_update_hook            sqlite3_api->update_hook
-#define sqlite3_user_data              sqlite3_api->user_data
-#define sqlite3_value_blob             sqlite3_api->value_blob
-#define sqlite3_value_bytes            sqlite3_api->value_bytes
-#define sqlite3_value_bytes16          sqlite3_api->value_bytes16
-#define sqlite3_value_double           sqlite3_api->value_double
-#define sqlite3_value_int              sqlite3_api->value_int
-#define sqlite3_value_int64            sqlite3_api->value_int64
-#define sqlite3_value_numeric_type     sqlite3_api->value_numeric_type
-#define sqlite3_value_text             sqlite3_api->value_text
-#define sqlite3_value_text16           sqlite3_api->value_text16
-#define sqlite3_value_text16be         sqlite3_api->value_text16be
-#define sqlite3_value_text16le         sqlite3_api->value_text16le
-#define sqlite3_value_type             sqlite3_api->value_type
-#define sqlite3_vmprintf               sqlite3_api->vmprintf
-#define sqlite3_overload_function      sqlite3_api->overload_function
-#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
-#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
-#define sqlite3_clear_bindings         sqlite3_api->clear_bindings
-#define sqlite3_bind_zeroblob          sqlite3_api->bind_zeroblob
-#define sqlite3_blob_bytes             sqlite3_api->blob_bytes
-#define sqlite3_blob_close             sqlite3_api->blob_close
-#define sqlite3_blob_open              sqlite3_api->blob_open
-#define sqlite3_blob_read              sqlite3_api->blob_read
-#define sqlite3_blob_write             sqlite3_api->blob_write
-#define sqlite3_create_collation_v2    sqlite3_api->create_collation_v2
-#define sqlite3_file_control           sqlite3_api->file_control
-#define sqlite3_memory_highwater       sqlite3_api->memory_highwater
-#define sqlite3_memory_used            sqlite3_api->memory_used
-#define sqlite3_mutex_alloc            sqlite3_api->mutex_alloc
-#define sqlite3_mutex_enter            sqlite3_api->mutex_enter
-#define sqlite3_mutex_free             sqlite3_api->mutex_free
-#define sqlite3_mutex_leave            sqlite3_api->mutex_leave
-#define sqlite3_mutex_try              sqlite3_api->mutex_try
-#define sqlite3_open_v2                sqlite3_api->open_v2
-#define sqlite3_release_memory         sqlite3_api->release_memory
-#define sqlite3_result_error_nomem     sqlite3_api->result_error_nomem
-#define sqlite3_result_error_toobig    sqlite3_api->result_error_toobig
-#define sqlite3_sleep                  sqlite3_api->sleep
-#define sqlite3_soft_heap_limit        sqlite3_api->soft_heap_limit
-#define sqlite3_vfs_find               sqlite3_api->vfs_find
-#define sqlite3_vfs_register           sqlite3_api->vfs_register
-#define sqlite3_vfs_unregister         sqlite3_api->vfs_unregister
-#define sqlite3_threadsafe             sqlite3_api->xthreadsafe
-#define sqlite3_result_zeroblob        sqlite3_api->result_zeroblob
-#define sqlite3_result_error_code      sqlite3_api->result_error_code
-#define sqlite3_test_control           sqlite3_api->test_control
-#define sqlite3_randomness             sqlite3_api->randomness
-#define sqlite3_context_db_handle      sqlite3_api->context_db_handle
-#endif /* SQLITE_CORE */
+SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3 *db, Token *pName){
+  char *zName;
+  if( pName ){
+    zName = sqlite3DbStrNDup(db, (char*)pName->z, pName->n);
+    sqlite3Dequote(zName);
+  }else{
+    zName = 0;
+  }
+  return zName;
+}
 
-#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api;
-#define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
+/*
+** Open the sqlite_master table stored in database number iDb for
+** writing. The table is opened using cursor 0.
+*/
+SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *p, int iDb){
+  Vdbe *v = sqlite3GetVdbe(p);
+  sqlite3TableLock(p, iDb, MASTER_ROOT, 1, SCHEMA_TABLE(iDb));
+  sqlite3VdbeAddOp3(v, OP_OpenWrite, 0, MASTER_ROOT, iDb);
+  sqlite3VdbeChangeP4(v, -1, (char *)5, P4_INT32);  /* 5 column table */
+  if( p->nTab==0 ){
+    p->nTab = 1;
+  }
+}
 
-#endif /* _SQLITE3EXT_H_ */
+/*
+** Parameter zName points to a nul-terminated buffer containing the name
+** of a database ("main", "temp" or the name of an attached db). This
+** function returns the index of the named database in db->aDb[], or
+** -1 if the named db cannot be found.
+*/
+SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *db, const char *zName){
+  int i = -1;         /* Database number */
+  if( zName ){
+    Db *pDb;
+    int n = sqlite3Strlen30(zName);
+    for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
+      if( (!OMIT_TEMPDB || i!=1 ) && n==sqlite3Strlen30(pDb->zName) && 
+          0==sqlite3StrICmp(pDb->zName, zName) ){
+        break;
+      }
+    }
+  }
+  return i;
+}
 
-/************** End of sqlite3ext.h ******************************************/
-/************** Continuing where we left off in loadext.c ********************/
+/*
+** The token *pName contains the name of a database (either "main" or
+** "temp" or the name of an attached db). This routine returns the
+** index of the named database in db->aDb[], or -1 if the named db 
+** does not exist.
+*/
+SQLITE_PRIVATE int sqlite3FindDb(sqlite3 *db, Token *pName){
+  int i;                               /* Database number */
+  char *zName;                         /* Name we are searching for */
+  zName = sqlite3NameFromToken(db, pName);
+  i = sqlite3FindDbName(db, zName);
+  sqlite3DbFree(db, zName);
+  return i;
+}
 
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/* The table or view or trigger name is passed to this routine via tokens
+** pName1 and pName2. If the table name was fully qualified, for example:
+**
+** CREATE TABLE xxx.yyy (...);
+** 
+** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
+** the table name is not fully qualified, i.e.:
+**
+** CREATE TABLE yyy(...);
+**
+** Then pName1 is set to "yyy" and pName2 is "".
+**
+** This routine sets the *ppUnqual pointer to point at the token (pName1 or
+** pName2) that stores the unqualified table name.  The index of the
+** database "xxx" is returned.
+*/
+SQLITE_PRIVATE int sqlite3TwoPartName(
+  Parse *pParse,      /* Parsing and code generating context */
+  Token *pName1,      /* The "xxx" in the name "xxx.yyy" or "xxx" */
+  Token *pName2,      /* The "yyy" in the name "xxx.yyy" */
+  Token **pUnqual     /* Write the unqualified object name here */
+){
+  int iDb;                    /* Database holding the object */
+  sqlite3 *db = pParse->db;
+
+  if( ALWAYS(pName2!=0) && pName2->n>0 ){
+    if( db->init.busy ) {
+      sqlite3ErrorMsg(pParse, "corrupt database");
+      pParse->nErr++;
+      return -1;
+    }
+    *pUnqual = pName2;
+    iDb = sqlite3FindDb(db, pName1);
+    if( iDb<0 ){
+      sqlite3ErrorMsg(pParse, "unknown database %T", pName1);
+      pParse->nErr++;
+      return -1;
+    }
+  }else{
+    assert( db->init.iDb==0 || db->init.busy );
+    iDb = db->init.iDb;
+    *pUnqual = pName1;
+  }
+  return iDb;
+}
 
 /*
-** Some API routines are omitted when various features are
-** excluded from a build of SQLite.  Substitute a NULL pointer
-** for any missing APIs.
+** This routine is used to check if the UTF-8 string zName is a legal
+** unqualified name for a new schema object (table, index, view or
+** trigger). All names are legal except those that begin with the string
+** "sqlite_" (in upper, lower or mixed case). This portion of the namespace
+** is reserved for internal use.
 */
-#ifndef SQLITE_ENABLE_COLUMN_METADATA
-# define sqlite3_column_database_name   0
-# define sqlite3_column_database_name16 0
-# define sqlite3_column_table_name      0
-# define sqlite3_column_table_name16    0
-# define sqlite3_column_origin_name     0
-# define sqlite3_column_origin_name16   0
-# define sqlite3_table_column_metadata  0
-#endif
+SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *pParse, const char *zName){
+  if( !pParse->db->init.busy && pParse->nested==0 
+          && (pParse->db->flags & SQLITE_WriteSchema)==0
+          && 0==sqlite3StrNICmp(zName, "sqlite_", 7) ){
+    sqlite3ErrorMsg(pParse, "object name reserved for internal use: %s", zName);
+    return SQLITE_ERROR;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Begin constructing a new table representation in memory.  This is
+** the first of several action routines that get called in response
+** to a CREATE TABLE statement.  In particular, this routine is called
+** after seeing tokens "CREATE" and "TABLE" and the table name. The isTemp
+** flag is true if the table should be stored in the auxiliary database
+** file instead of in the main database file.  This is normally the case
+** when the "TEMP" or "TEMPORARY" keyword occurs in between
+** CREATE and TABLE.
+**
+** The new table record is initialized and put in pParse->pNewTable.
+** As more of the CREATE TABLE statement is parsed, additional action
+** routines will be called to add more information to this record.
+** At the end of the CREATE TABLE statement, the sqlite3EndTable() routine
+** is called to complete the construction of the new table record.
+*/
+SQLITE_PRIVATE void sqlite3StartTable(
+  Parse *pParse,   /* Parser context */
+  Token *pName1,   /* First part of the name of the table or view */
+  Token *pName2,   /* Second part of the name of the table or view */
+  int isTemp,      /* True if this is a TEMP table */
+  int isView,      /* True if this is a VIEW */
+  int isVirtual,   /* True if this is a VIRTUAL table */
+  int noErr        /* Do nothing if table already exists */
+){
+  Table *pTable;
+  char *zName = 0; /* The name of the new table */
+  sqlite3 *db = pParse->db;
+  Vdbe *v;
+  int iDb;         /* Database number to create the table in */
+  Token *pName;    /* Unqualified name of the table to create */
+
+  /* The table or view name to create is passed to this routine via tokens
+  ** pName1 and pName2. If the table name was fully qualified, for example:
+  **
+  ** CREATE TABLE xxx.yyy (...);
+  ** 
+  ** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
+  ** the table name is not fully qualified, i.e.:
+  **
+  ** CREATE TABLE yyy(...);
+  **
+  ** Then pName1 is set to "yyy" and pName2 is "".
+  **
+  ** The call below sets the pName pointer to point at the token (pName1 or
+  ** pName2) that stores the unqualified table name. The variable iDb is
+  ** set to the index of the database that the table or view is to be
+  ** created in.
+  */
+  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
+  if( iDb<0 ) return;
+  if( !OMIT_TEMPDB && isTemp && iDb>1 ){
+    /* If creating a temp table, the name may not be qualified */
+    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
+    return;
+  }
+  if( !OMIT_TEMPDB && isTemp ) iDb = 1;
+
+  pParse->sNameToken = *pName;
+  zName = sqlite3NameFromToken(db, pName);
+  if( zName==0 ) return;
+  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
+    goto begin_table_error;
+  }
+  if( db->init.iDb==1 ) isTemp = 1;
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  assert( (isTemp & 1)==isTemp );
+  {
+    int code;
+    char *zDb = db->aDb[iDb].zName;
+    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(isTemp), 0, zDb) ){
+      goto begin_table_error;
+    }
+    if( isView ){
+      if( !OMIT_TEMPDB && isTemp ){
+        code = SQLITE_CREATE_TEMP_VIEW;
+      }else{
+        code = SQLITE_CREATE_VIEW;
+      }
+    }else{
+      if( !OMIT_TEMPDB && isTemp ){
+        code = SQLITE_CREATE_TEMP_TABLE;
+      }else{
+        code = SQLITE_CREATE_TABLE;
+      }
+    }
+    if( !isVirtual && sqlite3AuthCheck(pParse, code, zName, 0, zDb) ){
+      goto begin_table_error;
+    }
+  }
+#endif
+
+  /* Make sure the new table name does not collide with an existing
+  ** index or table name in the same database.  Issue an error message if
+  ** it does. The exception is if the statement being parsed was passed
+  ** to an sqlite3_declare_vtab() call. In that case only the column names
+  ** and types will be used, so there is no need to test for namespace
+  ** collisions.
+  */
+  if( !IN_DECLARE_VTAB ){
+    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+      goto begin_table_error;
+    }
+    pTable = sqlite3FindTable(db, zName, db->aDb[iDb].zName);
+    if( pTable ){
+      if( !noErr ){
+        sqlite3ErrorMsg(pParse, "table %T already exists", pName);
+      }
+      goto begin_table_error;
+    }
+    if( sqlite3FindIndex(db, zName, 0)!=0 && (iDb==0 || !db->init.busy) ){
+      sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
+      goto begin_table_error;
+    }
+  }
+
+  pTable = sqlite3DbMallocZero(db, sizeof(Table));
+  if( pTable==0 ){
+    db->mallocFailed = 1;
+    pParse->rc = SQLITE_NOMEM;
+    pParse->nErr++;
+    goto begin_table_error;
+  }
+  pTable->zName = zName;
+  pTable->iPKey = -1;
+  pTable->pSchema = db->aDb[iDb].pSchema;
+  pTable->nRef = 1;
+  pTable->dbMem = 0;
+  assert( pParse->pNewTable==0 );
+  pParse->pNewTable = pTable;
+
+  /* If this is the magic sqlite_sequence table used by autoincrement,
+  ** then record a pointer to this table in the main database structure
+  ** so that INSERT can find the table easily.
+  */
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+  if( !pParse->nested && strcmp(zName, "sqlite_sequence")==0 ){
+    pTable->pSchema->pSeqTab = pTable;
+  }
+#endif
+
+  /* Begin generating the code that will insert the table record into
+  ** the SQLITE_MASTER table.  Note in particular that we must go ahead
+  ** and allocate the record number for the table entry now.  Before any
+  ** PRIMARY KEY or UNIQUE keywords are parsed.  Those keywords will cause
+  ** indices to be created and the table record must come before the 
+  ** indices.  Hence, the record number for the table must be allocated
+  ** now.
+  */
+  if( !db->init.busy && (v = sqlite3GetVdbe(pParse))!=0 ){
+    int j1;
+    int fileFormat;
+    int reg1, reg2, reg3;
+    sqlite3BeginWriteOperation(pParse, 0, iDb);
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( isVirtual ){
+      sqlite3VdbeAddOp0(v, OP_VBegin);
+    }
+#endif
+
+    /* If the file format and encoding in the database have not been set, 
+    ** set them now.
+    */
+    reg1 = pParse->regRowid = ++pParse->nMem;
+    reg2 = pParse->regRoot = ++pParse->nMem;
+    reg3 = ++pParse->nMem;
+    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, reg3, BTREE_FILE_FORMAT);
+    sqlite3VdbeUsesBtree(v, iDb);
+    j1 = sqlite3VdbeAddOp1(v, OP_If, reg3);
+    fileFormat = (db->flags & SQLITE_LegacyFileFmt)!=0 ?
+                  1 : SQLITE_MAX_FILE_FORMAT;
+    sqlite3VdbeAddOp2(v, OP_Integer, fileFormat, reg3);
+    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, reg3);
+    sqlite3VdbeAddOp2(v, OP_Integer, ENC(db), reg3);
+    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_TEXT_ENCODING, reg3);
+    sqlite3VdbeJumpHere(v, j1);
+
+    /* This just creates a place-holder record in the sqlite_master table.
+    ** The record created does not contain anything yet.  It will be replaced
+    ** by the real entry in code generated at sqlite3EndTable().
+    **
+    ** The rowid for the new entry is left in register pParse->regRowid.
+    ** The root page number of the new table is left in reg pParse->regRoot.
+    ** The rowid and root page number values are needed by the code that
+    ** sqlite3EndTable will generate.
+    */
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
+    if( isView || isVirtual ){
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, reg2);
+    }else
+#endif
+    {
+      sqlite3VdbeAddOp2(v, OP_CreateTable, iDb, reg2);
+    }
+    sqlite3OpenMasterTable(pParse, iDb);
+    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, reg1);
+    sqlite3VdbeAddOp2(v, OP_Null, 0, reg3);
+    sqlite3VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
+    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+    sqlite3VdbeAddOp0(v, OP_Close);
+  }
+
+  /* Normal (non-error) return. */
+  return;
+
+  /* If an error occurs, we jump here */
+begin_table_error:
+  sqlite3DbFree(db, zName);
+  return;
+}
+
+/*
+** This macro is used to compare two strings in a case-insensitive manner.
+** It is slightly faster than calling sqlite3StrICmp() directly, but
+** produces larger code.
+**
+** WARNING: This macro is not compatible with the strcmp() family. It
+** returns true if the two strings are equal, otherwise false.
+*/
+#define STRICMP(x, y) (\
+sqlite3UpperToLower[*(unsigned char *)(x)]==   \
+sqlite3UpperToLower[*(unsigned char *)(y)]     \
+&& sqlite3StrICmp((x)+1,(y)+1)==0 )
+
+/*
+** Add a new column to the table currently being constructed.
+**
+** The parser calls this routine once for each column declaration
+** in a CREATE TABLE statement.  sqlite3StartTable() gets called
+** first to get things going.  Then this routine is called for each
+** column.
+*/
+SQLITE_PRIVATE void sqlite3AddColumn(Parse *pParse, Token *pName){
+  Table *p;
+  int i;
+  char *z;
+  Column *pCol;
+  sqlite3 *db = pParse->db;
+  if( (p = pParse->pNewTable)==0 ) return;
+#if SQLITE_MAX_COLUMN
+  if( p->nCol+1>db->aLimit[SQLITE_LIMIT_COLUMN] ){
+    sqlite3ErrorMsg(pParse, "too many columns on %s", p->zName);
+    return;
+  }
+#endif
+  z = sqlite3NameFromToken(db, pName);
+  if( z==0 ) return;
+  for(i=0; i<p->nCol; i++){
+    if( STRICMP(z, p->aCol[i].zName) ){
+      sqlite3ErrorMsg(pParse, "duplicate column name: %s", z);
+      sqlite3DbFree(db, z);
+      return;
+    }
+  }
+  if( (p->nCol & 0x7)==0 ){
+    Column *aNew;
+    aNew = sqlite3DbRealloc(db,p->aCol,(p->nCol+8)*sizeof(p->aCol[0]));
+    if( aNew==0 ){
+      sqlite3DbFree(db, z);
+      return;
+    }
+    p->aCol = aNew;
+  }
+  pCol = &p->aCol[p->nCol];
+  memset(pCol, 0, sizeof(p->aCol[0]));
+  pCol->zName = z;
+ 
+  /* If there is no type specified, columns have the default affinity
+  ** 'NONE'. If there is a type specified, then sqlite3AddColumnType() will
+  ** be called next to set pCol->affinity correctly.
+  */
+  pCol->affinity = SQLITE_AFF_NONE;
+  p->nCol++;
+}
+
+/*
+** This routine is called by the parser while in the middle of
+** parsing a CREATE TABLE statement.  A "NOT NULL" constraint has
+** been seen on a column.  This routine sets the notNull flag on
+** the column currently under construction.
+*/
+SQLITE_PRIVATE void sqlite3AddNotNull(Parse *pParse, int onError){
+  Table *p;
+  p = pParse->pNewTable;
+  if( p==0 || NEVER(p->nCol<1) ) return;
+  p->aCol[p->nCol-1].notNull = (u8)onError;
+}
+
+/*
+** Scan the column type name zType (length nType) and return the
+** associated affinity type.
+**
+** This routine does a case-independent search of zType for the 
+** substrings in the following table. If one of the substrings is
+** found, the corresponding affinity is returned. If zType contains
+** more than one of the substrings, entries toward the top of 
+** the table take priority. For example, if zType is 'BLOBINT', 
+** SQLITE_AFF_INTEGER is returned.
+**
+** Substring     | Affinity
+** --------------------------------
+** 'INT'         | SQLITE_AFF_INTEGER
+** 'CHAR'        | SQLITE_AFF_TEXT
+** 'CLOB'        | SQLITE_AFF_TEXT
+** 'TEXT'        | SQLITE_AFF_TEXT
+** 'BLOB'        | SQLITE_AFF_NONE
+** 'REAL'        | SQLITE_AFF_REAL
+** 'FLOA'        | SQLITE_AFF_REAL
+** 'DOUB'        | SQLITE_AFF_REAL
+**
+** If none of the substrings in the above table are found,
+** SQLITE_AFF_NUMERIC is returned.
+*/
+SQLITE_PRIVATE char sqlite3AffinityType(const char *zIn){
+  u32 h = 0;
+  char aff = SQLITE_AFF_NUMERIC;
+
+  if( zIn ) while( zIn[0] ){
+    h = (h<<8) + sqlite3UpperToLower[(*zIn)&0xff];
+    zIn++;
+    if( h==(('c'<<24)+('h'<<16)+('a'<<8)+'r') ){             /* CHAR */
+      aff = SQLITE_AFF_TEXT; 
+    }else if( h==(('c'<<24)+('l'<<16)+('o'<<8)+'b') ){       /* CLOB */
+      aff = SQLITE_AFF_TEXT;
+    }else if( h==(('t'<<24)+('e'<<16)+('x'<<8)+'t') ){       /* TEXT */
+      aff = SQLITE_AFF_TEXT;
+    }else if( h==(('b'<<24)+('l'<<16)+('o'<<8)+'b')          /* BLOB */
+        && (aff==SQLITE_AFF_NUMERIC || aff==SQLITE_AFF_REAL) ){
+      aff = SQLITE_AFF_NONE;
+#ifndef SQLITE_OMIT_FLOATING_POINT
+    }else if( h==(('r'<<24)+('e'<<16)+('a'<<8)+'l')          /* REAL */
+        && aff==SQLITE_AFF_NUMERIC ){
+      aff = SQLITE_AFF_REAL;
+    }else if( h==(('f'<<24)+('l'<<16)+('o'<<8)+'a')          /* FLOA */
+        && aff==SQLITE_AFF_NUMERIC ){
+      aff = SQLITE_AFF_REAL;
+    }else if( h==(('d'<<24)+('o'<<16)+('u'<<8)+'b')          /* DOUB */
+        && aff==SQLITE_AFF_NUMERIC ){
+      aff = SQLITE_AFF_REAL;
+#endif
+    }else if( (h&0x00FFFFFF)==(('i'<<16)+('n'<<8)+'t') ){    /* INT */
+      aff = SQLITE_AFF_INTEGER;
+      break;
+    }
+  }
+
+  return aff;
+}
+
+/*
+** This routine is called by the parser while in the middle of
+** parsing a CREATE TABLE statement.  The pFirst token is the first
+** token in the sequence of tokens that describe the type of the
+** column currently under construction.   pLast is the last token
+** in the sequence.  Use this information to construct a string
+** that contains the typename of the column and store that string
+** in zType.
+*/ 
+SQLITE_PRIVATE void sqlite3AddColumnType(Parse *pParse, Token *pType){
+  Table *p;
+  Column *pCol;
+
+  p = pParse->pNewTable;
+  if( p==0 || NEVER(p->nCol<1) ) return;
+  pCol = &p->aCol[p->nCol-1];
+  assert( pCol->zType==0 );
+  pCol->zType = sqlite3NameFromToken(pParse->db, pType);
+  pCol->affinity = sqlite3AffinityType(pCol->zType);
+}
+
+/*
+** The expression is the default value for the most recently added column
+** of the table currently under construction.
+**
+** Default value expressions must be constant.  Raise an exception if this
+** is not the case.
+**
+** This routine is called by the parser while in the middle of
+** parsing a CREATE TABLE statement.
+*/
+SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse *pParse, ExprSpan *pSpan){
+  Table *p;
+  Column *pCol;
+  sqlite3 *db = pParse->db;
+  p = pParse->pNewTable;
+  if( p!=0 ){
+    pCol = &(p->aCol[p->nCol-1]);
+    if( !sqlite3ExprIsConstantOrFunction(pSpan->pExpr) ){
+      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
+          pCol->zName);
+    }else{
+      /* A copy of pExpr is used instead of the original, as pExpr contains
+      ** tokens that point to volatile memory. The 'span' of the expression
+      ** is required by pragma table_info.
+      */
+      sqlite3ExprDelete(db, pCol->pDflt);
+      pCol->pDflt = sqlite3ExprDup(db, pSpan->pExpr, EXPRDUP_REDUCE);
+      sqlite3DbFree(db, pCol->zDflt);
+      pCol->zDflt = sqlite3DbStrNDup(db, (char*)pSpan->zStart,
+                                     (int)(pSpan->zEnd - pSpan->zStart));
+    }
+  }
+  sqlite3ExprDelete(db, pSpan->pExpr);
+}
+
+/*
+** Designate the PRIMARY KEY for the table.  pList is a list of names 
+** of columns that form the primary key.  If pList is NULL, then the
+** most recently added column of the table is the primary key.
+**
+** A table can have at most one primary key.  If the table already has
+** a primary key (and this is the second primary key) then create an
+** error.
+**
+** If the PRIMARY KEY is on a single column whose datatype is INTEGER,
+** then we will try to use that column as the rowid.  Set the Table.iPKey
+** field of the table under construction to be the index of the
+** INTEGER PRIMARY KEY column.  Table.iPKey is set to -1 if there is
+** no INTEGER PRIMARY KEY.
+**
+** If the key is not an INTEGER PRIMARY KEY, then create a unique
+** index for the key.  No index is created for INTEGER PRIMARY KEYs.
+*/
+SQLITE_PRIVATE void sqlite3AddPrimaryKey(
+  Parse *pParse,    /* Parsing context */
+  ExprList *pList,  /* List of field names to be indexed */
+  int onError,      /* What to do with a uniqueness conflict */
+  int autoInc,      /* True if the AUTOINCREMENT keyword is present */
+  int sortOrder     /* SQLITE_SO_ASC or SQLITE_SO_DESC */
+){
+  Table *pTab = pParse->pNewTable;
+  char *zType = 0;
+  int iCol = -1, i;
+  if( pTab==0 || IN_DECLARE_VTAB ) goto primary_key_exit;
+  if( pTab->tabFlags & TF_HasPrimaryKey ){
+    sqlite3ErrorMsg(pParse, 
+      "table \"%s\" has more than one primary key", pTab->zName);
+    goto primary_key_exit;
+  }
+  pTab->tabFlags |= TF_HasPrimaryKey;
+  if( pList==0 ){
+    iCol = pTab->nCol - 1;
+    pTab->aCol[iCol].isPrimKey = 1;
+  }else{
+    for(i=0; i<pList->nExpr; i++){
+      for(iCol=0; iCol<pTab->nCol; iCol++){
+        if( sqlite3StrICmp(pList->a[i].zName, pTab->aCol[iCol].zName)==0 ){
+          break;
+        }
+      }
+      if( iCol<pTab->nCol ){
+        pTab->aCol[iCol].isPrimKey = 1;
+      }
+    }
+    if( pList->nExpr>1 ) iCol = -1;
+  }
+  if( iCol>=0 && iCol<pTab->nCol ){
+    zType = pTab->aCol[iCol].zType;
+  }
+  if( zType && sqlite3StrICmp(zType, "INTEGER")==0
+        && sortOrder==SQLITE_SO_ASC ){
+    pTab->iPKey = iCol;
+    pTab->keyConf = (u8)onError;
+    assert( autoInc==0 || autoInc==1 );
+    pTab->tabFlags |= autoInc*TF_Autoincrement;
+  }else if( autoInc ){
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+    sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
+       "INTEGER PRIMARY KEY");
+#endif
+  }else{
+    Index *p;
+    p = sqlite3CreateIndex(pParse, 0, 0, 0, pList, onError, 0, 0, sortOrder, 0);
+    if( p ){
+      p->autoIndex = 2;
+    }
+    pList = 0;
+  }
+
+primary_key_exit:
+  sqlite3ExprListDelete(pParse->db, pList);
+  return;
+}
+
+/*
+** Add a new CHECK constraint to the table currently under construction.
+*/
+SQLITE_PRIVATE void sqlite3AddCheckConstraint(
+  Parse *pParse,    /* Parsing context */
+  Expr *pCheckExpr  /* The check expression */
+){
+  sqlite3 *db = pParse->db;
+#ifndef SQLITE_OMIT_CHECK
+  Table *pTab = pParse->pNewTable;
+  if( pTab && !IN_DECLARE_VTAB ){
+    pTab->pCheck = sqlite3ExprAnd(db, pTab->pCheck, pCheckExpr);
+  }else
+#endif
+  {
+    sqlite3ExprDelete(db, pCheckExpr);
+  }
+}
+
+/*
+** Set the collation function of the most recently parsed table column
+** to the CollSeq given.
+*/
+SQLITE_PRIVATE void sqlite3AddCollateType(Parse *pParse, Token *pToken){
+  Table *p;
+  int i;
+  char *zColl;              /* Dequoted name of collation sequence */
+  sqlite3 *db;
+
+  if( (p = pParse->pNewTable)==0 ) return;
+  i = p->nCol-1;
+  db = pParse->db;
+  zColl = sqlite3NameFromToken(db, pToken);
+  if( !zColl ) return;
+
+  if( sqlite3LocateCollSeq(pParse, zColl) ){
+    Index *pIdx;
+    p->aCol[i].zColl = zColl;
+  
+    /* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
+    ** then an index may have been created on this column before the
+    ** collation type was added. Correct this if it is the case.
+    */
+    for(pIdx=p->pIndex; pIdx; pIdx=pIdx->pNext){
+      assert( pIdx->nColumn==1 );
+      if( pIdx->aiColumn[0]==i ){
+        pIdx->azColl[0] = p->aCol[i].zColl;
+      }
+    }
+  }else{
+    sqlite3DbFree(db, zColl);
+  }
+}
+
+/*
+** This function returns the collation sequence for database native text
+** encoding identified by the string zName, length nName.
+**
+** If the requested collation sequence is not available, or not available
+** in the database native encoding, the collation factory is invoked to
+** request it. If the collation factory does not supply such a sequence,
+** and the sequence is available in another text encoding, then that is
+** returned instead.
+**
+** If no versions of the requested collations sequence are available, or
+** another error occurs, NULL is returned and an error message written into
+** pParse.
+**
+** This routine is a wrapper around sqlite3FindCollSeq().  This routine
+** invokes the collation factory if the named collation cannot be found
+** and generates an error message.
+**
+** See also: sqlite3FindCollSeq(), sqlite3GetCollSeq()
+*/
+SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName){
+  sqlite3 *db = pParse->db;
+  u8 enc = ENC(db);
+  u8 initbusy = db->init.busy;
+  CollSeq *pColl;
+
+  pColl = sqlite3FindCollSeq(db, enc, zName, initbusy);
+  if( !initbusy && (!pColl || !pColl->xCmp) ){
+    pColl = sqlite3GetCollSeq(db, enc, pColl, zName);
+    if( !pColl ){
+      sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
+    }
+  }
+
+  return pColl;
+}
+
+
+/*
+** Generate code that will increment the schema cookie.
+**
+** The schema cookie is used to determine when the schema for the
+** database changes.  After each schema change, the cookie value
+** changes.  When a process first reads the schema it records the
+** cookie.  Thereafter, whenever it goes to access the database,
+** it checks the cookie to make sure the schema has not changed
+** since it was last read.
+**
+** This plan is not completely bullet-proof.  It is possible for
+** the schema to change multiple times and for the cookie to be
+** set back to prior value.  But schema changes are infrequent
+** and the probability of hitting the same cookie value is only
+** 1 chance in 2^32.  So we're safe enough.
+*/
+SQLITE_PRIVATE void sqlite3ChangeCookie(Parse *pParse, int iDb){
+  int r1 = sqlite3GetTempReg(pParse);
+  sqlite3 *db = pParse->db;
+  Vdbe *v = pParse->pVdbe;
+  sqlite3VdbeAddOp2(v, OP_Integer, db->aDb[iDb].pSchema->schema_cookie+1, r1);
+  sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_SCHEMA_VERSION, r1);
+  sqlite3ReleaseTempReg(pParse, r1);
+}
+
+/*
+** Measure the number of characters needed to output the given
+** identifier.  The number returned includes any quotes used
+** but does not include the null terminator.
+**
+** The estimate is conservative.  It might be larger that what is
+** really needed.
+*/
+static int identLength(const char *z){
+  int n;
+  for(n=0; *z; n++, z++){
+    if( *z=='"' ){ n++; }
+  }
+  return n + 2;
+}
+
+/*
+** The first parameter is a pointer to an output buffer. The second 
+** parameter is a pointer to an integer that contains the offset at
+** which to write into the output buffer. This function copies the
+** nul-terminated string pointed to by the third parameter, zSignedIdent,
+** to the specified offset in the buffer and updates *pIdx to refer
+** to the first byte after the last byte written before returning.
+** 
+** If the string zSignedIdent consists entirely of alpha-numeric
+** characters, does not begin with a digit and is not an SQL keyword,
+** then it is copied to the output buffer exactly as it is. Otherwise,
+** it is quoted using double-quotes.
+*/
+static void identPut(char *z, int *pIdx, char *zSignedIdent){
+  unsigned char *zIdent = (unsigned char*)zSignedIdent;
+  int i, j, needQuote;
+  i = *pIdx;
+
+  for(j=0; zIdent[j]; j++){
+    if( !sqlite3Isalnum(zIdent[j]) && zIdent[j]!='_' ) break;
+  }
+  needQuote = sqlite3Isdigit(zIdent[0]) || sqlite3KeywordCode(zIdent, j)!=TK_ID;
+  if( !needQuote ){
+    needQuote = zIdent[j];
+  }
+
+  if( needQuote ) z[i++] = '"';
+  for(j=0; zIdent[j]; j++){
+    z[i++] = zIdent[j];
+    if( zIdent[j]=='"' ) z[i++] = '"';
+  }
+  if( needQuote ) z[i++] = '"';
+  z[i] = 0;
+  *pIdx = i;
+}
+
+/*
+** Generate a CREATE TABLE statement appropriate for the given
+** table.  Memory to hold the text of the statement is obtained
+** from sqliteMalloc() and must be freed by the calling function.
+*/
+static char *createTableStmt(sqlite3 *db, Table *p){
+  int i, k, n;
+  char *zStmt;
+  char *zSep, *zSep2, *zEnd;
+  Column *pCol;
+  n = 0;
+  for(pCol = p->aCol, i=0; i<p->nCol; i++, pCol++){
+    n += identLength(pCol->zName) + 5;
+  }
+  n += identLength(p->zName);
+  if( n<50 ){ 
+    zSep = "";
+    zSep2 = ",";
+    zEnd = ")";
+  }else{
+    zSep = "\n  ";
+    zSep2 = ",\n  ";
+    zEnd = "\n)";
+  }
+  n += 35 + 6*p->nCol;
+  zStmt = sqlite3Malloc( n );
+  if( zStmt==0 ){
+    db->mallocFailed = 1;
+    return 0;
+  }
+  sqlite3_snprintf(n, zStmt, "CREATE TABLE ");
+  k = sqlite3Strlen30(zStmt);
+  identPut(zStmt, &k, p->zName);
+  zStmt[k++] = '(';
+  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
+    static const char * const azType[] = {
+        /* SQLITE_AFF_TEXT    */ " TEXT",
+        /* SQLITE_AFF_NONE    */ "",
+        /* SQLITE_AFF_NUMERIC */ " NUM",
+        /* SQLITE_AFF_INTEGER */ " INT",
+        /* SQLITE_AFF_REAL    */ " REAL"
+    };
+    int len;
+    const char *zType;
+
+    sqlite3_snprintf(n-k, &zStmt[k], zSep);
+    k += sqlite3Strlen30(&zStmt[k]);
+    zSep = zSep2;
+    identPut(zStmt, &k, pCol->zName);
+    assert( pCol->affinity-SQLITE_AFF_TEXT >= 0 );
+    assert( pCol->affinity-SQLITE_AFF_TEXT < sizeof(azType)/sizeof(azType[0]) );
+    testcase( pCol->affinity==SQLITE_AFF_TEXT );
+    testcase( pCol->affinity==SQLITE_AFF_NONE );
+    testcase( pCol->affinity==SQLITE_AFF_NUMERIC );
+    testcase( pCol->affinity==SQLITE_AFF_INTEGER );
+    testcase( pCol->affinity==SQLITE_AFF_REAL );
+    
+    zType = azType[pCol->affinity - SQLITE_AFF_TEXT];
+    len = sqlite3Strlen30(zType);
+    assert( pCol->affinity==SQLITE_AFF_NONE 
+            || pCol->affinity==sqlite3AffinityType(zType) );
+    memcpy(&zStmt[k], zType, len);
+    k += len;
+    assert( k<=n );
+  }
+  sqlite3_snprintf(n-k, &zStmt[k], "%s", zEnd);
+  return zStmt;
+}
+
+/*
+** This routine is called to report the final ")" that terminates
+** a CREATE TABLE statement.
+**
+** The table structure that other action routines have been building
+** is added to the internal hash tables, assuming no errors have
+** occurred.
+**
+** An entry for the table is made in the master table on disk, unless
+** this is a temporary table or db->init.busy==1.  When db->init.busy==1
+** it means we are reading the sqlite_master table because we just
+** connected to the database or because the sqlite_master table has
+** recently changed, so the entry for this table already exists in
+** the sqlite_master table.  We do not want to create it again.
+**
+** If the pSelect argument is not NULL, it means that this routine
+** was called to create a table generated from a 
+** "CREATE TABLE ... AS SELECT ..." statement.  The column names of
+** the new table will match the result set of the SELECT.
+*/
+SQLITE_PRIVATE void sqlite3EndTable(
+  Parse *pParse,          /* Parse context */
+  Token *pCons,           /* The ',' token after the last column defn. */
+  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
+  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
+){
+  Table *p;
+  sqlite3 *db = pParse->db;
+  int iDb;
+
+  if( (pEnd==0 && pSelect==0) || db->mallocFailed ){
+    return;
+  }
+  p = pParse->pNewTable;
+  if( p==0 ) return;
+
+  assert( !db->init.busy || !pSelect );
+
+  iDb = sqlite3SchemaToIndex(db, p->pSchema);
+
+#ifndef SQLITE_OMIT_CHECK
+  /* Resolve names in all CHECK constraint expressions.
+  */
+  if( p->pCheck ){
+    SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
+    NameContext sNC;                /* Name context for pParse->pNewTable */
+
+    memset(&sNC, 0, sizeof(sNC));
+    memset(&sSrc, 0, sizeof(sSrc));
+    sSrc.nSrc = 1;
+    sSrc.a[0].zName = p->zName;
+    sSrc.a[0].pTab = p;
+    sSrc.a[0].iCursor = -1;
+    sNC.pParse = pParse;
+    sNC.pSrcList = &sSrc;
+    sNC.isCheck = 1;
+    if( sqlite3ResolveExprNames(&sNC, p->pCheck) ){
+      return;
+    }
+  }
+#endif /* !defined(SQLITE_OMIT_CHECK) */
+
+  /* If the db->init.busy is 1 it means we are reading the SQL off the
+  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
+  ** So do not write to the disk again.  Extract the root page number
+  ** for the table from the db->init.newTnum field.  (The page number
+  ** should have been put there by the sqliteOpenCb routine.)
+  */
+  if( db->init.busy ){
+    p->tnum = db->init.newTnum;
+  }
+
+  /* If not initializing, then create a record for the new table
+  ** in the SQLITE_MASTER table of the database.
+  **
+  ** If this is a TEMPORARY table, write the entry into the auxiliary
+  ** file instead of into the main database file.
+  */
+  if( !db->init.busy ){
+    int n;
+    Vdbe *v;
+    char *zType;    /* "view" or "table" */
+    char *zType2;   /* "VIEW" or "TABLE" */
+    char *zStmt;    /* Text of the CREATE TABLE or CREATE VIEW statement */
+
+    v = sqlite3GetVdbe(pParse);
+    if( NEVER(v==0) ) return;
+
+    sqlite3VdbeAddOp1(v, OP_Close, 0);
+
+    /* 
+    ** Initialize zType for the new view or table.
+    */
+    if( p->pSelect==0 ){
+      /* A regular table */
+      zType = "table";
+      zType2 = "TABLE";
+#ifndef SQLITE_OMIT_VIEW
+    }else{
+      /* A view */
+      zType = "view";
+      zType2 = "VIEW";
+#endif
+    }
+
+    /* If this is a CREATE TABLE xx AS SELECT ..., execute the SELECT
+    ** statement to populate the new table. The root-page number for the
+    ** new table is in register pParse->regRoot.
+    **
+    ** Once the SELECT has been coded by sqlite3Select(), it is in a
+    ** suitable state to query for the column names and types to be used
+    ** by the new table.
+    **
+    ** A shared-cache write-lock is not required to write to the new table,
+    ** as a schema-lock must have already been obtained to create it. Since
+    ** a schema-lock excludes all other database users, the write-lock would
+    ** be redundant.
+    */
+    if( pSelect ){
+      SelectDest dest;
+      Table *pSelTab;
+
+      assert(pParse->nTab==1);
+      sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
+      sqlite3VdbeChangeP5(v, 1);
+      pParse->nTab = 2;
+      sqlite3SelectDestInit(&dest, SRT_Table, 1);
+      sqlite3Select(pParse, pSelect, &dest);
+      sqlite3VdbeAddOp1(v, OP_Close, 1);
+      if( pParse->nErr==0 ){
+        pSelTab = sqlite3ResultSetOfSelect(pParse, pSelect);
+        if( pSelTab==0 ) return;
+        assert( p->aCol==0 );
+        p->nCol = pSelTab->nCol;
+        p->aCol = pSelTab->aCol;
+        pSelTab->nCol = 0;
+        pSelTab->aCol = 0;
+        sqlite3DeleteTable(pSelTab);
+      }
+    }
+
+    /* Compute the complete text of the CREATE statement */
+    if( pSelect ){
+      zStmt = createTableStmt(db, p);
+    }else{
+      n = (int)(pEnd->z - pParse->sNameToken.z) + 1;
+      zStmt = sqlite3MPrintf(db, 
+          "CREATE %s %.*s", zType2, n, pParse->sNameToken.z
+      );
+    }
+
+    /* A slot for the record has already been allocated in the 
+    ** SQLITE_MASTER table.  We just need to update that slot with all
+    ** the information we've collected.
+    */
+    sqlite3NestedParse(pParse,
+      "UPDATE %Q.%s "
+         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=#%d, sql=%Q "
+       "WHERE rowid=#%d",
+      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
+      zType,
+      p->zName,
+      p->zName,
+      pParse->regRoot,
+      zStmt,
+      pParse->regRowid
+    );
+    sqlite3DbFree(db, zStmt);
+    sqlite3ChangeCookie(pParse, iDb);
+
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+    /* Check to see if we need to create an sqlite_sequence table for
+    ** keeping track of autoincrement keys.
+    */
+    if( p->tabFlags & TF_Autoincrement ){
+      Db *pDb = &db->aDb[iDb];
+      if( pDb->pSchema->pSeqTab==0 ){
+        sqlite3NestedParse(pParse,
+          "CREATE TABLE %Q.sqlite_sequence(name,seq)",
+          pDb->zName
+        );
+      }
+    }
+#endif
+
+    /* Reparse everything to update our internal data structures */
+    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0,
+        sqlite3MPrintf(db, "tbl_name='%q'",p->zName), P4_DYNAMIC);
+  }
+
+
+  /* Add the table to the in-memory representation of the database.
+  */
+  if( db->init.busy ){
+    Table *pOld;
+    Schema *pSchema = p->pSchema;
+    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName,
+                             sqlite3Strlen30(p->zName),p);
+    if( pOld ){
+      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
+      db->mallocFailed = 1;
+      return;
+    }
+    pParse->pNewTable = 0;
+    db->nTable++;
+    db->flags |= SQLITE_InternChanges;
+
+#ifndef SQLITE_OMIT_ALTERTABLE
+    if( !p->pSelect ){
+      const char *zName = (const char *)pParse->sNameToken.z;
+      int nName;
+      assert( !pSelect && pCons && pEnd );
+      if( pCons->z==0 ){
+        pCons = pEnd;
+      }
+      nName = (int)((const char *)pCons->z - zName);
+      p->addColOffset = 13 + sqlite3Utf8CharLen(zName, nName);
+    }
+#endif
+  }
+}
+
+#ifndef SQLITE_OMIT_VIEW
+/*
+** The parser calls this routine in order to create a new VIEW
+*/
+SQLITE_PRIVATE void sqlite3CreateView(
+  Parse *pParse,     /* The parsing context */
+  Token *pBegin,     /* The CREATE token that begins the statement */
+  Token *pName1,     /* The token that holds the name of the view */
+  Token *pName2,     /* The token that holds the name of the view */
+  Select *pSelect,   /* A SELECT statement that will become the new view */
+  int isTemp,        /* TRUE for a TEMPORARY view */
+  int noErr          /* Suppress error messages if VIEW already exists */
+){
+  Table *p;
+  int n;
+  const char *z;
+  Token sEnd;
+  DbFixer sFix;
+  Token *pName;
+  int iDb;
+  sqlite3 *db = pParse->db;
+
+  if( pParse->nVar>0 ){
+    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
+    sqlite3SelectDelete(db, pSelect);
+    return;
+  }
+  sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
+  p = pParse->pNewTable;
+  if( p==0 ){
+    sqlite3SelectDelete(db, pSelect);
+    return;
+  }
+  assert( pParse->nErr==0 ); /* If sqlite3StartTable return non-NULL then
+                             ** there could not have been an error */
+  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
+  iDb = sqlite3SchemaToIndex(db, p->pSchema);
+  if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
+    && sqlite3FixSelect(&sFix, pSelect)
+  ){
+    sqlite3SelectDelete(db, pSelect);
+    return;
+  }
+
+  /* Make a copy of the entire SELECT statement that defines the view.
+  ** This will force all the Expr.token.z values to be dynamically
+  ** allocated rather than point to the input string - which means that
+  ** they will persist after the current sqlite3_exec() call returns.
+  */
+  p->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
+  sqlite3SelectDelete(db, pSelect);
+  if( db->mallocFailed ){
+    return;
+  }
+  if( !db->init.busy ){
+    sqlite3ViewGetColumnNames(pParse, p);
+  }
+
+  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
+  ** the end.
+  */
+  sEnd = pParse->sLastToken;
+  if( ALWAYS(sEnd.z[0]!=0) && sEnd.z[0]!=';' ){
+    sEnd.z += sEnd.n;
+  }
+  sEnd.n = 0;
+  n = (int)(sEnd.z - pBegin->z);
+  z = pBegin->z;
+  while( ALWAYS(n>0) && sqlite3Isspace(z[n-1]) ){ n--; }
+  sEnd.z = &z[n-1];
+  sEnd.n = 1;
+
+  /* Use sqlite3EndTable() to add the view to the SQLITE_MASTER table */
+  sqlite3EndTable(pParse, 0, &sEnd, 0);
+  return;
+}
+#endif /* SQLITE_OMIT_VIEW */
+
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
+/*
+** The Table structure pTable is really a VIEW.  Fill in the names of
+** the columns of the view in the pTable structure.  Return the number
+** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
+*/
+SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
+  Table *pSelTab;   /* A fake table from which we get the result set */
+  Select *pSel;     /* Copy of the SELECT that implements the view */
+  int nErr = 0;     /* Number of errors encountered */
+  int n;            /* Temporarily holds the number of cursors assigned */
+  sqlite3 *db = pParse->db;  /* Database connection for malloc errors */
+  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
+
+  assert( pTable );
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( sqlite3VtabCallConnect(pParse, pTable) ){
+    return SQLITE_ERROR;
+  }
+  if( IsVirtual(pTable) ) return 0;
+#endif
+
+#ifndef SQLITE_OMIT_VIEW
+  /* A positive nCol means the columns names for this view are
+  ** already known.
+  */
+  if( pTable->nCol>0 ) return 0;
+
+  /* A negative nCol is a special marker meaning that we are currently
+  ** trying to compute the column names.  If we enter this routine with
+  ** a negative nCol, it means two or more views form a loop, like this:
+  **
+  **     CREATE VIEW one AS SELECT * FROM two;
+  **     CREATE VIEW two AS SELECT * FROM one;
+  **
+  ** Actually, the error above is now caught prior to reaching this point.
+  ** But the following test is still important as it does come up
+  ** in the following:
+  ** 
+  **     CREATE TABLE main.ex1(a);
+  **     CREATE TEMP VIEW ex1 AS SELECT a FROM ex1;
+  **     SELECT * FROM temp.ex1;
+  */
+  if( pTable->nCol<0 ){
+    sqlite3ErrorMsg(pParse, "view %s is circularly defined", pTable->zName);
+    return 1;
+  }
+  assert( pTable->nCol>=0 );
+
+  /* If we get this far, it means we need to compute the table names.
+  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
+  ** "*" elements in the results set of the view and will assign cursors
+  ** to the elements of the FROM clause.  But we do not want these changes
+  ** to be permanent.  So the computation is done on a copy of the SELECT
+  ** statement that defines the view.
+  */
+  assert( pTable->pSelect );
+  pSel = sqlite3SelectDup(db, pTable->pSelect, 0);
+  if( pSel ){
+    u8 enableLookaside = db->lookaside.bEnabled;
+    n = pParse->nTab;
+    sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
+    pTable->nCol = -1;
+    db->lookaside.bEnabled = 0;
+#ifndef SQLITE_OMIT_AUTHORIZATION
+    xAuth = db->xAuth;
+    db->xAuth = 0;
+    pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
+    db->xAuth = xAuth;
+#else
+    pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
+#endif
+    db->lookaside.bEnabled = enableLookaside;
+    pParse->nTab = n;
+    if( pSelTab ){
+      assert( pTable->aCol==0 );
+      pTable->nCol = pSelTab->nCol;
+      pTable->aCol = pSelTab->aCol;
+      pSelTab->nCol = 0;
+      pSelTab->aCol = 0;
+      sqlite3DeleteTable(pSelTab);
+      pTable->pSchema->flags |= DB_UnresetViews;
+    }else{
+      pTable->nCol = 0;
+      nErr++;
+    }
+    sqlite3SelectDelete(db, pSel);
+  } else {
+    nErr++;
+  }
+#endif /* SQLITE_OMIT_VIEW */
+  return nErr;  
+}
+#endif /* !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) */
+
+#ifndef SQLITE_OMIT_VIEW
+/*
+** Clear the column names from every VIEW in database idx.
+*/
+static void sqliteViewResetAll(sqlite3 *db, int idx){
+  HashElem *i;
+  if( !DbHasProperty(db, idx, DB_UnresetViews) ) return;
+  for(i=sqliteHashFirst(&db->aDb[idx].pSchema->tblHash); i;i=sqliteHashNext(i)){
+    Table *pTab = sqliteHashData(i);
+    if( pTab->pSelect ){
+      sqliteResetColumnNames(pTab);
+    }
+  }
+  DbClearProperty(db, idx, DB_UnresetViews);
+}
+#else
+# define sqliteViewResetAll(A,B)
+#endif /* SQLITE_OMIT_VIEW */
+
+/*
+** This function is called by the VDBE to adjust the internal schema
+** used by SQLite when the btree layer moves a table root page. The
+** root-page of a table or index in database iDb has changed from iFrom
+** to iTo.
+**
+** Ticket #1728:  The symbol table might still contain information
+** on tables and/or indices that are the process of being deleted.
+** If you are unlucky, one of those deleted indices or tables might
+** have the same rootpage number as the real table or index that is
+** being moved.  So we cannot stop searching after the first match 
+** because the first match might be for one of the deleted indices
+** or tables and not the table/index that is actually being moved.
+** We must continue looping until all tables and indices with
+** rootpage==iFrom have been converted to have a rootpage of iTo
+** in order to be certain that we got the right one.
+*/
+#ifndef SQLITE_OMIT_AUTOVACUUM
+SQLITE_PRIVATE void sqlite3RootPageMoved(Db *pDb, int iFrom, int iTo){
+  HashElem *pElem;
+  Hash *pHash;
+
+  pHash = &pDb->pSchema->tblHash;
+  for(pElem=sqliteHashFirst(pHash); pElem; pElem=sqliteHashNext(pElem)){
+    Table *pTab = sqliteHashData(pElem);
+    if( pTab->tnum==iFrom ){
+      pTab->tnum = iTo;
+    }
+  }
+  pHash = &pDb->pSchema->idxHash;
+  for(pElem=sqliteHashFirst(pHash); pElem; pElem=sqliteHashNext(pElem)){
+    Index *pIdx = sqliteHashData(pElem);
+    if( pIdx->tnum==iFrom ){
+      pIdx->tnum = iTo;
+    }
+  }
+}
+#endif
+
+/*
+** Write code to erase the table with root-page iTable from database iDb.
+** Also write code to modify the sqlite_master table and internal schema
+** if a root-page of another table is moved by the btree-layer whilst
+** erasing iTable (this can happen with an auto-vacuum database).
+*/ 
+static void destroyRootPage(Parse *pParse, int iTable, int iDb){
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  int r1 = sqlite3GetTempReg(pParse);
+  sqlite3VdbeAddOp3(v, OP_Destroy, iTable, r1, iDb);
+  sqlite3MayAbort(pParse);
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  /* OP_Destroy stores an in integer r1. If this integer
+  ** is non-zero, then it is the root page number of a table moved to
+  ** location iTable. The following code modifies the sqlite_master table to
+  ** reflect this.
+  **
+  ** The "#NNN" in the SQL is a special constant that means whatever value
+  ** is in register NNN.  See grammar rules associated with the TK_REGISTER
+  ** token for additional information.
+  */
+  sqlite3NestedParse(pParse, 
+     "UPDATE %Q.%s SET rootpage=%d WHERE #%d AND rootpage=#%d",
+     pParse->db->aDb[iDb].zName, SCHEMA_TABLE(iDb), iTable, r1, r1);
+#endif
+  sqlite3ReleaseTempReg(pParse, r1);
+}
+
+/*
+** Write VDBE code to erase table pTab and all associated indices on disk.
+** Code to update the sqlite_master tables and internal schema definitions
+** in case a root-page belonging to another table is moved by the btree layer
+** is also added (this can happen with an auto-vacuum database).
+*/
+static void destroyTable(Parse *pParse, Table *pTab){
+#ifdef SQLITE_OMIT_AUTOVACUUM
+  Index *pIdx;
+  int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+  destroyRootPage(pParse, pTab->tnum, iDb);
+  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+    destroyRootPage(pParse, pIdx->tnum, iDb);
+  }
+#else
+  /* If the database may be auto-vacuum capable (if SQLITE_OMIT_AUTOVACUUM
+  ** is not defined), then it is important to call OP_Destroy on the
+  ** table and index root-pages in order, starting with the numerically 
+  ** largest root-page number. This guarantees that none of the root-pages
+  ** to be destroyed is relocated by an earlier OP_Destroy. i.e. if the
+  ** following were coded:
+  **
+  ** OP_Destroy 4 0
+  ** ...
+  ** OP_Destroy 5 0
+  **
+  ** and root page 5 happened to be the largest root-page number in the
+  ** database, then root page 5 would be moved to page 4 by the 
+  ** "OP_Destroy 4 0" opcode. The subsequent "OP_Destroy 5 0" would hit
+  ** a free-list page.
+  */
+  int iTab = pTab->tnum;
+  int iDestroyed = 0;
+
+  while( 1 ){
+    Index *pIdx;
+    int iLargest = 0;
+
+    if( iDestroyed==0 || iTab<iDestroyed ){
+      iLargest = iTab;
+    }
+    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+      int iIdx = pIdx->tnum;
+      assert( pIdx->pSchema==pTab->pSchema );
+      if( (iDestroyed==0 || (iIdx<iDestroyed)) && iIdx>iLargest ){
+        iLargest = iIdx;
+      }
+    }
+    if( iLargest==0 ){
+      return;
+    }else{
+      int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+      destroyRootPage(pParse, iLargest, iDb);
+      iDestroyed = iLargest;
+    }
+  }
+#endif
+}
+
+/*
+** This routine is called to do the work of a DROP TABLE statement.
+** pName is the name of the table to be dropped.
+*/
+SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
+  Table *pTab;
+  Vdbe *v;
+  sqlite3 *db = pParse->db;
+  int iDb;
+
+  if( db->mallocFailed ){
+    goto exit_drop_table;
+  }
+  assert( pParse->nErr==0 );
+  assert( pName->nSrc==1 );
+  pTab = sqlite3LocateTable(pParse, isView, 
+                            pName->a[0].zName, pName->a[0].zDatabase);
+
+  if( pTab==0 ){
+    if( noErr ){
+      sqlite3ErrorClear(pParse);
+    }
+    goto exit_drop_table;
+  }
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  assert( iDb>=0 && iDb<db->nDb );
+
+  /* If pTab is a virtual table, call ViewGetColumnNames() to ensure
+  ** it is initialized.
+  */
+  if( IsVirtual(pTab) && sqlite3ViewGetColumnNames(pParse, pTab) ){
+    goto exit_drop_table;
+  }
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  {
+    int code;
+    const char *zTab = SCHEMA_TABLE(iDb);
+    const char *zDb = db->aDb[iDb].zName;
+    const char *zArg2 = 0;
+    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb)){
+      goto exit_drop_table;
+    }
+    if( isView ){
+      if( !OMIT_TEMPDB && iDb==1 ){
+        code = SQLITE_DROP_TEMP_VIEW;
+      }else{
+        code = SQLITE_DROP_VIEW;
+      }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    }else if( IsVirtual(pTab) ){
+      code = SQLITE_DROP_VTABLE;
+      zArg2 = sqlite3GetVTable(db, pTab)->pMod->zName;
+#endif
+    }else{
+      if( !OMIT_TEMPDB && iDb==1 ){
+        code = SQLITE_DROP_TEMP_TABLE;
+      }else{
+        code = SQLITE_DROP_TABLE;
+      }
+    }
+    if( sqlite3AuthCheck(pParse, code, pTab->zName, zArg2, zDb) ){
+      goto exit_drop_table;
+    }
+    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
+      goto exit_drop_table;
+    }
+  }
+#endif
+  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
+    sqlite3ErrorMsg(pParse, "table %s may not be dropped", pTab->zName);
+    goto exit_drop_table;
+  }
+
+#ifndef SQLITE_OMIT_VIEW
+  /* Ensure DROP TABLE is not used on a view, and DROP VIEW is not used
+  ** on a table.
+  */
+  if( isView && pTab->pSelect==0 ){
+    sqlite3ErrorMsg(pParse, "use DROP TABLE to delete table %s", pTab->zName);
+    goto exit_drop_table;
+  }
+  if( !isView && pTab->pSelect ){
+    sqlite3ErrorMsg(pParse, "use DROP VIEW to delete view %s", pTab->zName);
+    goto exit_drop_table;
+  }
+#endif
+
+  /* Generate code to remove the table from the master table
+  ** on disk.
+  */
+  v = sqlite3GetVdbe(pParse);
+  if( v ){
+    Trigger *pTrigger;
+    Db *pDb = &db->aDb[iDb];
+    sqlite3BeginWriteOperation(pParse, 1, iDb);
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( IsVirtual(pTab) ){
+      sqlite3VdbeAddOp0(v, OP_VBegin);
+    }
+#endif
+    sqlite3FkDropTable(pParse, pName, pTab);
+
+    /* Drop all triggers associated with the table being dropped. Code
+    ** is generated to remove entries from sqlite_master and/or
+    ** sqlite_temp_master if required.
+    */
+    pTrigger = sqlite3TriggerList(pParse, pTab);
+    while( pTrigger ){
+      assert( pTrigger->pSchema==pTab->pSchema || 
+          pTrigger->pSchema==db->aDb[1].pSchema );
+      sqlite3DropTriggerPtr(pParse, pTrigger);
+      pTrigger = pTrigger->pNext;
+    }
+
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+    /* Remove any entries of the sqlite_sequence table associated with
+    ** the table being dropped. This is done before the table is dropped
+    ** at the btree level, in case the sqlite_sequence table needs to
+    ** move as a result of the drop (can happen in auto-vacuum mode).
+    */
+    if( pTab->tabFlags & TF_Autoincrement ){
+      sqlite3NestedParse(pParse,
+        "DELETE FROM %s.sqlite_sequence WHERE name=%Q",
+        pDb->zName, pTab->zName
+      );
+    }
+#endif
+
+    /* Drop all SQLITE_MASTER table and index entries that refer to the
+    ** table. The program name loops through the master table and deletes
+    ** every row that refers to a table of the same name as the one being
+    ** dropped. Triggers are handled seperately because a trigger can be
+    ** created in the temp database that refers to a table in another
+    ** database.
+    */
+    sqlite3NestedParse(pParse, 
+        "DELETE FROM %Q.%s WHERE tbl_name=%Q and type!='trigger'",
+        pDb->zName, SCHEMA_TABLE(iDb), pTab->zName);
+
+    /* Drop any statistics from the sqlite_stat1 table, if it exists */
+    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
+      sqlite3NestedParse(pParse,
+        "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q", pDb->zName, pTab->zName
+      );
+    }
+
+    if( !isView && !IsVirtual(pTab) ){
+      destroyTable(pParse, pTab);
+    }
+
+    /* Remove the table entry from SQLite's internal schema and modify
+    ** the schema cookie.
+    */
+    if( IsVirtual(pTab) ){
+      sqlite3VdbeAddOp4(v, OP_VDestroy, iDb, 0, 0, pTab->zName, 0);
+    }
+    sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
+    sqlite3ChangeCookie(pParse, iDb);
+  }
+  sqliteViewResetAll(db, iDb);
+
+exit_drop_table:
+  sqlite3SrcListDelete(db, pName);
+}
+
+/*
+** This routine is called to create a new foreign key on the table
+** currently under construction.  pFromCol determines which columns
+** in the current table point to the foreign key.  If pFromCol==0 then
+** connect the key to the last column inserted.  pTo is the name of
+** the table referred to.  pToCol is a list of tables in the other
+** pTo table that the foreign key points to.  flags contains all
+** information about the conflict resolution algorithms specified
+** in the ON DELETE, ON UPDATE and ON INSERT clauses.
+**
+** An FKey structure is created and added to the table currently
+** under construction in the pParse->pNewTable field.
+**
+** The foreign key is set for IMMEDIATE processing.  A subsequent call
+** to sqlite3DeferForeignKey() might change this to DEFERRED.
+*/
+SQLITE_PRIVATE void sqlite3CreateForeignKey(
+  Parse *pParse,       /* Parsing context */
+  ExprList *pFromCol,  /* Columns in this table that point to other table */
+  Token *pTo,          /* Name of the other table */
+  ExprList *pToCol,    /* Columns in the other table */
+  int flags            /* Conflict resolution algorithms. */
+){
+  sqlite3 *db = pParse->db;
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+  FKey *pFKey = 0;
+  FKey *pNextTo;
+  Table *p = pParse->pNewTable;
+  int nByte;
+  int i;
+  int nCol;
+  char *z;
+
+  assert( pTo!=0 );
+  if( p==0 || IN_DECLARE_VTAB ) goto fk_end;
+  if( pFromCol==0 ){
+    int iCol = p->nCol-1;
+    if( NEVER(iCol<0) ) goto fk_end;
+    if( pToCol && pToCol->nExpr!=1 ){
+      sqlite3ErrorMsg(pParse, "foreign key on %s"
+         " should reference only one column of table %T",
+         p->aCol[iCol].zName, pTo);
+      goto fk_end;
+    }
+    nCol = 1;
+  }else if( pToCol && pToCol->nExpr!=pFromCol->nExpr ){
+    sqlite3ErrorMsg(pParse,
+        "number of columns in foreign key does not match the number of "
+        "columns in the referenced table");
+    goto fk_end;
+  }else{
+    nCol = pFromCol->nExpr;
+  }
+  nByte = sizeof(*pFKey) + (nCol-1)*sizeof(pFKey->aCol[0]) + pTo->n + 1;
+  if( pToCol ){
+    for(i=0; i<pToCol->nExpr; i++){
+      nByte += sqlite3Strlen30(pToCol->a[i].zName) + 1;
+    }
+  }
+  pFKey = sqlite3DbMallocZero(db, nByte );
+  if( pFKey==0 ){
+    goto fk_end;
+  }
+  pFKey->pFrom = p;
+  pFKey->pNextFrom = p->pFKey;
+  z = (char*)&pFKey->aCol[nCol];
+  pFKey->zTo = z;
+  memcpy(z, pTo->z, pTo->n);
+  z[pTo->n] = 0;
+  sqlite3Dequote(z);
+  z += pTo->n+1;
+  pFKey->nCol = nCol;
+  if( pFromCol==0 ){
+    pFKey->aCol[0].iFrom = p->nCol-1;
+  }else{
+    for(i=0; i<nCol; i++){
+      int j;
+      for(j=0; j<p->nCol; j++){
+        if( sqlite3StrICmp(p->aCol[j].zName, pFromCol->a[i].zName)==0 ){
+          pFKey->aCol[i].iFrom = j;
+          break;
+        }
+      }
+      if( j>=p->nCol ){
+        sqlite3ErrorMsg(pParse, 
+          "unknown column \"%s\" in foreign key definition", 
+          pFromCol->a[i].zName);
+        goto fk_end;
+      }
+    }
+  }
+  if( pToCol ){
+    for(i=0; i<nCol; i++){
+      int n = sqlite3Strlen30(pToCol->a[i].zName);
+      pFKey->aCol[i].zCol = z;
+      memcpy(z, pToCol->a[i].zName, n);
+      z[n] = 0;
+      z += n+1;
+    }
+  }
+  pFKey->isDeferred = 0;
+  pFKey->aAction[0] = (u8)(flags & 0xff);            /* ON DELETE action */
+  pFKey->aAction[1] = (u8)((flags >> 8 ) & 0xff);    /* ON UPDATE action */
+
+  pNextTo = (FKey *)sqlite3HashInsert(&p->pSchema->fkeyHash, 
+      pFKey->zTo, sqlite3Strlen30(pFKey->zTo), (void *)pFKey
+  );
+  if( pNextTo==pFKey ){
+    db->mallocFailed = 1;
+    goto fk_end;
+  }
+  if( pNextTo ){
+    assert( pNextTo->pPrevTo==0 );
+    pFKey->pNextTo = pNextTo;
+    pNextTo->pPrevTo = pFKey;
+  }
+
+  /* Link the foreign key to the table as the last step.
+  */
+  p->pFKey = pFKey;
+  pFKey = 0;
+
+fk_end:
+  sqlite3DbFree(db, pFKey);
+#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
+  sqlite3ExprListDelete(db, pFromCol);
+  sqlite3ExprListDelete(db, pToCol);
+}
+
+/*
+** This routine is called when an INITIALLY IMMEDIATE or INITIALLY DEFERRED
+** clause is seen as part of a foreign key definition.  The isDeferred
+** parameter is 1 for INITIALLY DEFERRED and 0 for INITIALLY IMMEDIATE.
+** The behavior of the most recently created foreign key is adjusted
+** accordingly.
+*/
+SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse *pParse, int isDeferred){
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+  Table *pTab;
+  FKey *pFKey;
+  if( (pTab = pParse->pNewTable)==0 || (pFKey = pTab->pFKey)==0 ) return;
+  assert( isDeferred==0 || isDeferred==1 ); /* EV: R-30323-21917 */
+  pFKey->isDeferred = (u8)isDeferred;
+#endif
+}
+
+/*
+** Generate code that will erase and refill index *pIdx.  This is
+** used to initialize a newly created index or to recompute the
+** content of an index in response to a REINDEX command.
+**
+** if memRootPage is not negative, it means that the index is newly
+** created.  The register specified by memRootPage contains the
+** root page number of the index.  If memRootPage is negative, then
+** the index already exists and must be cleared before being refilled and
+** the root page number of the index is taken from pIndex->tnum.
+*/
+static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
+  Table *pTab = pIndex->pTable;  /* The table that is indexed */
+  int iTab = pParse->nTab++;     /* Btree cursor used for pTab */
+  int iIdx = pParse->nTab++;     /* Btree cursor used for pIndex */
+  int addr1;                     /* Address of top of loop */
+  int tnum;                      /* Root page of index */
+  Vdbe *v;                       /* Generate code into this virtual machine */
+  KeyInfo *pKey;                 /* KeyInfo for index */
+  int regIdxKey;                 /* Registers containing the index key */
+  int regRecord;                 /* Register holding assemblied index record */
+  sqlite3 *db = pParse->db;      /* The database connection */
+  int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
+
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  if( sqlite3AuthCheck(pParse, SQLITE_REINDEX, pIndex->zName, 0,
+      db->aDb[iDb].zName ) ){
+    return;
+  }
+#endif
+
+  /* Require a write-lock on the table to perform this operation */
+  sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
+
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ) return;
+  if( memRootPage>=0 ){
+    tnum = memRootPage;
+  }else{
+    tnum = pIndex->tnum;
+    sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
+  }
+  pKey = sqlite3IndexKeyinfo(pParse, pIndex);
+  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
+                    (char *)pKey, P4_KEYINFO_HANDOFF);
+  if( memRootPage>=0 ){
+    sqlite3VdbeChangeP5(v, 1);
+  }
+  sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
+  addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
+  regRecord = sqlite3GetTempReg(pParse);
+  regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
+  if( pIndex->onError!=OE_None ){
+    const int regRowid = regIdxKey + pIndex->nColumn;
+    const int j2 = sqlite3VdbeCurrentAddr(v) + 2;
+    void * const pRegKey = SQLITE_INT_TO_PTR(regIdxKey);
+
+    /* The registers accessed by the OP_IsUnique opcode were allocated
+    ** using sqlite3GetTempRange() inside of the sqlite3GenerateIndexKey()
+    ** call above. Just before that function was freed they were released
+    ** (made available to the compiler for reuse) using 
+    ** sqlite3ReleaseTempRange(). So in some ways having the OP_IsUnique
+    ** opcode use the values stored within seems dangerous. However, since
+    ** we can be sure that no other temp registers have been allocated
+    ** since sqlite3ReleaseTempRange() was called, it is safe to do so.
+    */
+    sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx, j2, regRowid, pRegKey, P4_INT32);
+    sqlite3HaltConstraint(
+        pParse, OE_Abort, "indexed columns are not unique", P4_STATIC);
+  }
+  sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
+  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
+  sqlite3ReleaseTempReg(pParse, regRecord);
+  sqlite3VdbeAddOp2(v, OP_Next, iTab, addr1+1);
+  sqlite3VdbeJumpHere(v, addr1);
+  sqlite3VdbeAddOp1(v, OP_Close, iTab);
+  sqlite3VdbeAddOp1(v, OP_Close, iIdx);
+}
+
+/*
+** Create a new index for an SQL table.  pName1.pName2 is the name of the index 
+** and pTblList is the name of the table that is to be indexed.  Both will 
+** be NULL for a primary key or an index that is created to satisfy a
+** UNIQUE constraint.  If pTable and pIndex are NULL, use pParse->pNewTable
+** as the table to be indexed.  pParse->pNewTable is a table that is
+** currently being constructed by a CREATE TABLE statement.
+**
+** pList is a list of columns to be indexed.  pList will be NULL if this
+** is a primary key or unique-constraint on the most recent column added
+** to the table currently under construction.  
+**
+** If the index is created successfully, return a pointer to the new Index
+** structure. This is used by sqlite3AddPrimaryKey() to mark the index
+** as the tables primary key (Index.autoIndex==2).
+*/
+SQLITE_PRIVATE Index *sqlite3CreateIndex(
+  Parse *pParse,     /* All information about this parse */
+  Token *pName1,     /* First part of index name. May be NULL */
+  Token *pName2,     /* Second part of index name. May be NULL */
+  SrcList *pTblName, /* Table to index. Use pParse->pNewTable if 0 */
+  ExprList *pList,   /* A list of columns to be indexed */
+  int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
+  Token *pStart,     /* The CREATE token that begins this statement */
+  Token *pEnd,       /* The ")" that closes the CREATE INDEX statement */
+  int sortOrder,     /* Sort order of primary key when pList==NULL */
+  int ifNotExist     /* Omit error if index already exists */
+){
+  Index *pRet = 0;     /* Pointer to return */
+  Table *pTab = 0;     /* Table to be indexed */
+  Index *pIndex = 0;   /* The index to be created */
+  char *zName = 0;     /* Name of the index */
+  int nName;           /* Number of characters in zName */
+  int i, j;
+  Token nullId;        /* Fake token for an empty ID list */
+  DbFixer sFix;        /* For assigning database names to pTable */
+  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
+  sqlite3 *db = pParse->db;
+  Db *pDb;             /* The specific table containing the indexed database */
+  int iDb;             /* Index of the database that is being written */
+  Token *pName = 0;    /* Unqualified name of the index to create */
+  struct ExprList_item *pListItem; /* For looping over pList */
+  int nCol;
+  int nExtra = 0;
+  char *zExtra;
+
+  assert( pStart==0 || pEnd!=0 ); /* pEnd must be non-NULL if pStart is */
+  assert( pParse->nErr==0 );      /* Never called with prior errors */
+  if( db->mallocFailed || IN_DECLARE_VTAB ){
+    goto exit_create_index;
+  }
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    goto exit_create_index;
+  }
+
+  /*
+  ** Find the table that is to be indexed.  Return early if not found.
+  */
+  if( pTblName!=0 ){
+
+    /* Use the two-part index name to determine the database 
+    ** to search for the table. 'Fix' the table name to this db
+    ** before looking up the table.
+    */
+    assert( pName1 && pName2 );
+    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
+    if( iDb<0 ) goto exit_create_index;
+
+#ifndef SQLITE_OMIT_TEMPDB
+    /* If the index name was unqualified, check if the the table
+    ** is a temp table. If so, set the database to 1. Do not do this
+    ** if initialising a database schema.
+    */
+    if( !db->init.busy ){
+      pTab = sqlite3SrcListLookup(pParse, pTblName);
+      if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
+        iDb = 1;
+      }
+    }
+#endif
+
+    if( sqlite3FixInit(&sFix, pParse, iDb, "index", pName) &&
+        sqlite3FixSrcList(&sFix, pTblName)
+    ){
+      /* Because the parser constructs pTblName from a single identifier,
+      ** sqlite3FixSrcList can never fail. */
+      assert(0);
+    }
+    pTab = sqlite3LocateTable(pParse, 0, pTblName->a[0].zName, 
+        pTblName->a[0].zDatabase);
+    if( !pTab || db->mallocFailed ) goto exit_create_index;
+    assert( db->aDb[iDb].pSchema==pTab->pSchema );
+  }else{
+    assert( pName==0 );
+    pTab = pParse->pNewTable;
+    if( !pTab ) goto exit_create_index;
+    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  }
+  pDb = &db->aDb[iDb];
+
+  assert( pTab!=0 );
+  assert( pParse->nErr==0 );
+  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 
+       && memcmp(&pTab->zName[7],"altertab_",9)!=0 ){
+    sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
+    goto exit_create_index;
+  }
+#ifndef SQLITE_OMIT_VIEW
+  if( pTab->pSelect ){
+    sqlite3ErrorMsg(pParse, "views may not be indexed");
+    goto exit_create_index;
+  }
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( IsVirtual(pTab) ){
+    sqlite3ErrorMsg(pParse, "virtual tables may not be indexed");
+    goto exit_create_index;
+  }
+#endif
+
+  /*
+  ** Find the name of the index.  Make sure there is not already another
+  ** index or table with the same name.  
+  **
+  ** Exception:  If we are reading the names of permanent indices from the
+  ** sqlite_master table (because some other process changed the schema) and
+  ** one of the index names collides with the name of a temporary table or
+  ** index, then we will continue to process this index.
+  **
+  ** If pName==0 it means that we are
+  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
+  ** own name.
+  */
+  if( pName ){
+    zName = sqlite3NameFromToken(db, pName);
+    if( zName==0 ) goto exit_create_index;
+    if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
+      goto exit_create_index;
+    }
+    if( !db->init.busy ){
+      if( sqlite3FindTable(db, zName, 0)!=0 ){
+        sqlite3ErrorMsg(pParse, "there is already a table named %s", zName);
+        goto exit_create_index;
+      }
+    }
+    if( sqlite3FindIndex(db, zName, pDb->zName)!=0 ){
+      if( !ifNotExist ){
+        sqlite3ErrorMsg(pParse, "index %s already exists", zName);
+      }
+      goto exit_create_index;
+    }
+  }else{
+    int n;
+    Index *pLoop;
+    for(pLoop=pTab->pIndex, n=1; pLoop; pLoop=pLoop->pNext, n++){}
+    zName = sqlite3MPrintf(db, "sqlite_autoindex_%s_%d", pTab->zName, n);
+    if( zName==0 ){
+      goto exit_create_index;
+    }
+  }
+
+  /* Check for authorization to create an index.
+  */
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  {
+    const char *zDb = pDb->zName;
+    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iDb), 0, zDb) ){
+      goto exit_create_index;
+    }
+    i = SQLITE_CREATE_INDEX;
+    if( !OMIT_TEMPDB && iDb==1 ) i = SQLITE_CREATE_TEMP_INDEX;
+    if( sqlite3AuthCheck(pParse, i, zName, pTab->zName, zDb) ){
+      goto exit_create_index;
+    }
+  }
+#endif
+
+  /* If pList==0, it means this routine was called to make a primary
+  ** key out of the last column added to the table under construction.
+  ** So create a fake list to simulate this.
+  */
+  if( pList==0 ){
+    nullId.z = pTab->aCol[pTab->nCol-1].zName;
+    nullId.n = sqlite3Strlen30((char*)nullId.z);
+    pList = sqlite3ExprListAppend(pParse, 0, 0);
+    if( pList==0 ) goto exit_create_index;
+    sqlite3ExprListSetName(pParse, pList, &nullId, 0);
+    pList->a[0].sortOrder = (u8)sortOrder;
+  }
+
+  /* Figure out how many bytes of space are required to store explicitly
+  ** specified collation sequence names.
+  */
+  for(i=0; i<pList->nExpr; i++){
+    Expr *pExpr = pList->a[i].pExpr;
+    if( pExpr ){
+      CollSeq *pColl = pExpr->pColl;
+      /* Either pColl!=0 or there was an OOM failure.  But if an OOM
+      ** failure we have quit before reaching this point. */
+      if( ALWAYS(pColl) ){
+        nExtra += (1 + sqlite3Strlen30(pColl->zName));
+      }
+    }
+  }
+
+  /* 
+  ** Allocate the index structure. 
+  */
+  nName = sqlite3Strlen30(zName);
+  nCol = pList->nExpr;
+  pIndex = sqlite3DbMallocZero(db, 
+      sizeof(Index) +              /* Index structure  */
+      sizeof(int)*nCol +           /* Index.aiColumn   */
+      sizeof(int)*(nCol+1) +       /* Index.aiRowEst   */
+      sizeof(char *)*nCol +        /* Index.azColl     */
+      sizeof(u8)*nCol +            /* Index.aSortOrder */
+      nName + 1 +                  /* Index.zName      */
+      nExtra                       /* Collation sequence names */
+  );
+  if( db->mallocFailed ){
+    goto exit_create_index;
+  }
+  pIndex->azColl = (char**)(&pIndex[1]);
+  pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
+  pIndex->aiRowEst = (unsigned *)(&pIndex->aiColumn[nCol]);
+  pIndex->aSortOrder = (u8 *)(&pIndex->aiRowEst[nCol+1]);
+  pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
+  zExtra = (char *)(&pIndex->zName[nName+1]);
+  memcpy(pIndex->zName, zName, nName+1);
+  pIndex->pTable = pTab;
+  pIndex->nColumn = pList->nExpr;
+  pIndex->onError = (u8)onError;
+  pIndex->autoIndex = (u8)(pName==0);
+  pIndex->pSchema = db->aDb[iDb].pSchema;
+
+  /* Check to see if we should honor DESC requests on index columns
+  */
+  if( pDb->pSchema->file_format>=4 ){
+    sortOrderMask = -1;   /* Honor DESC */
+  }else{
+    sortOrderMask = 0;    /* Ignore DESC */
+  }
+
+  /* Scan the names of the columns of the table to be indexed and
+  ** load the column indices into the Index structure.  Report an error
+  ** if any column is not found.
+  **
+  ** TODO:  Add a test to make sure that the same column is not named
+  ** more than once within the same index.  Only the first instance of
+  ** the column will ever be used by the optimizer.  Note that using the
+  ** same column more than once cannot be an error because that would 
+  ** break backwards compatibility - it needs to be a warning.
+  */
+  for(i=0, pListItem=pList->a; i<pList->nExpr; i++, pListItem++){
+    const char *zColName = pListItem->zName;
+    Column *pTabCol;
+    int requestedSortOrder;
+    char *zColl;                   /* Collation sequence name */
+
+    for(j=0, pTabCol=pTab->aCol; j<pTab->nCol; j++, pTabCol++){
+      if( sqlite3StrICmp(zColName, pTabCol->zName)==0 ) break;
+    }
+    if( j>=pTab->nCol ){
+      sqlite3ErrorMsg(pParse, "table %s has no column named %s",
+        pTab->zName, zColName);
+      goto exit_create_index;
+    }
+    pIndex->aiColumn[i] = j;
+    /* Justification of the ALWAYS(pListItem->pExpr->pColl):  Because of
+    ** the way the "idxlist" non-terminal is constructed by the parser,
+    ** if pListItem->pExpr is not null then either pListItem->pExpr->pColl
+    ** must exist or else there must have been an OOM error.  But if there
+    ** was an OOM error, we would never reach this point. */
+    if( pListItem->pExpr && ALWAYS(pListItem->pExpr->pColl) ){
+      int nColl;
+      zColl = pListItem->pExpr->pColl->zName;
+      nColl = sqlite3Strlen30(zColl) + 1;
+      assert( nExtra>=nColl );
+      memcpy(zExtra, zColl, nColl);
+      zColl = zExtra;
+      zExtra += nColl;
+      nExtra -= nColl;
+    }else{
+      zColl = pTab->aCol[j].zColl;
+      if( !zColl ){
+        zColl = db->pDfltColl->zName;
+      }
+    }
+    if( !db->init.busy && !sqlite3LocateCollSeq(pParse, zColl) ){
+      goto exit_create_index;
+    }
+    pIndex->azColl[i] = zColl;
+    requestedSortOrder = pListItem->sortOrder & sortOrderMask;
+    pIndex->aSortOrder[i] = (u8)requestedSortOrder;
+  }
+  sqlite3DefaultRowEst(pIndex);
+
+  if( pTab==pParse->pNewTable ){
+    /* This routine has been called to create an automatic index as a
+    ** result of a PRIMARY KEY or UNIQUE clause on a column definition, or
+    ** a PRIMARY KEY or UNIQUE clause following the column definitions.
+    ** i.e. one of:
+    **
+    ** CREATE TABLE t(x PRIMARY KEY, y);
+    ** CREATE TABLE t(x, y, UNIQUE(x, y));
+    **
+    ** Either way, check to see if the table already has such an index. If
+    ** so, don't bother creating this one. This only applies to
+    ** automatically created indices. Users can do as they wish with
+    ** explicit indices.
+    **
+    ** Two UNIQUE or PRIMARY KEY constraints are considered equivalent
+    ** (and thus suppressing the second one) even if they have different
+    ** sort orders.
+    **
+    ** If there are different collating sequences or if the columns of
+    ** the constraint occur in different orders, then the constraints are
+    ** considered distinct and both result in separate indices.
+    */
+    Index *pIdx;
+    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+      int k;
+      assert( pIdx->onError!=OE_None );
+      assert( pIdx->autoIndex );
+      assert( pIndex->onError!=OE_None );
+
+      if( pIdx->nColumn!=pIndex->nColumn ) continue;
+      for(k=0; k<pIdx->nColumn; k++){
+        const char *z1;
+        const char *z2;
+        if( pIdx->aiColumn[k]!=pIndex->aiColumn[k] ) break;
+        z1 = pIdx->azColl[k];
+        z2 = pIndex->azColl[k];
+        if( z1!=z2 && sqlite3StrICmp(z1, z2) ) break;
+      }
+      if( k==pIdx->nColumn ){
+        if( pIdx->onError!=pIndex->onError ){
+          /* This constraint creates the same index as a previous
+          ** constraint specified somewhere in the CREATE TABLE statement.
+          ** However the ON CONFLICT clauses are different. If both this 
+          ** constraint and the previous equivalent constraint have explicit
+          ** ON CONFLICT clauses this is an error. Otherwise, use the
+          ** explicitly specified behaviour for the index.
+          */
+          if( !(pIdx->onError==OE_Default || pIndex->onError==OE_Default) ){
+            sqlite3ErrorMsg(pParse, 
+                "conflicting ON CONFLICT clauses specified", 0);
+          }
+          if( pIdx->onError==OE_Default ){
+            pIdx->onError = pIndex->onError;
+          }
+        }
+        goto exit_create_index;
+      }
+    }
+  }
+
+  /* Link the new Index structure to its table and to the other
+  ** in-memory database structures. 
+  */
+  if( db->init.busy ){
+    Index *p;
+    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 
+                          pIndex->zName, sqlite3Strlen30(pIndex->zName),
+                          pIndex);
+    if( p ){
+      assert( p==pIndex );  /* Malloc must have failed */
+      db->mallocFailed = 1;
+      goto exit_create_index;
+    }
+    db->flags |= SQLITE_InternChanges;
+    if( pTblName!=0 ){
+      pIndex->tnum = db->init.newTnum;
+    }
+  }
+
+  /* If the db->init.busy is 0 then create the index on disk.  This
+  ** involves writing the index into the master table and filling in the
+  ** index with the current table contents.
+  **
+  ** The db->init.busy is 0 when the user first enters a CREATE INDEX 
+  ** command.  db->init.busy is 1 when a database is opened and 
+  ** CREATE INDEX statements are read out of the master table.  In
+  ** the latter case the index already exists on disk, which is why
+  ** we don't want to recreate it.
+  **
+  ** If pTblName==0 it means this index is generated as a primary key
+  ** or UNIQUE constraint of a CREATE TABLE statement.  Since the table
+  ** has just been created, it contains no data and the index initialization
+  ** step can be skipped.
+  */
+  else{ /* if( db->init.busy==0 ) */
+    Vdbe *v;
+    char *zStmt;
+    int iMem = ++pParse->nMem;
+
+    v = sqlite3GetVdbe(pParse);
+    if( v==0 ) goto exit_create_index;
+
+
+    /* Create the rootpage for the index
+    */
+    sqlite3BeginWriteOperation(pParse, 1, iDb);
+    sqlite3VdbeAddOp2(v, OP_CreateIndex, iDb, iMem);
+
+    /* Gather the complete text of the CREATE INDEX statement into
+    ** the zStmt variable
+    */
+    if( pStart ){
+      assert( pEnd!=0 );
+      /* A named index with an explicit CREATE INDEX statement */
+      zStmt = sqlite3MPrintf(db, "CREATE%s INDEX %.*s",
+        onError==OE_None ? "" : " UNIQUE",
+        pEnd->z - pName->z + 1,
+        pName->z);
+    }else{
+      /* An automatic index created by a PRIMARY KEY or UNIQUE constraint */
+      /* zStmt = sqlite3MPrintf(""); */
+      zStmt = 0;
+    }
+
+    /* Add an entry in sqlite_master for this index
+    */
+    sqlite3NestedParse(pParse, 
+        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,#%d,%Q);",
+        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
+        pIndex->zName,
+        pTab->zName,
+        iMem,
+        zStmt
+    );
+    sqlite3DbFree(db, zStmt);
+
+    /* Fill the index with data and reparse the schema. Code an OP_Expire
+    ** to invalidate all pre-compiled statements.
+    */
+    if( pTblName ){
+      sqlite3RefillIndex(pParse, pIndex, iMem);
+      sqlite3ChangeCookie(pParse, iDb);
+      sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0,
+         sqlite3MPrintf(db, "name='%q'", pIndex->zName), P4_DYNAMIC);
+      sqlite3VdbeAddOp1(v, OP_Expire, 0);
+    }
+  }
+
+  /* When adding an index to the list of indices for a table, make
+  ** sure all indices labeled OE_Replace come after all those labeled
+  ** OE_Ignore.  This is necessary for the correct constraint check
+  ** processing (in sqlite3GenerateConstraintChecks()) as part of
+  ** UPDATE and INSERT statements.  
+  */
+  if( db->init.busy || pTblName==0 ){
+    if( onError!=OE_Replace || pTab->pIndex==0
+         || pTab->pIndex->onError==OE_Replace){
+      pIndex->pNext = pTab->pIndex;
+      pTab->pIndex = pIndex;
+    }else{
+      Index *pOther = pTab->pIndex;
+      while( pOther->pNext && pOther->pNext->onError!=OE_Replace ){
+        pOther = pOther->pNext;
+      }
+      pIndex->pNext = pOther->pNext;
+      pOther->pNext = pIndex;
+    }
+    pRet = pIndex;
+    pIndex = 0;
+  }
+
+  /* Clean up before exiting */
+exit_create_index:
+  if( pIndex ){
+    sqlite3_free(pIndex->zColAff);
+    sqlite3DbFree(db, pIndex);
+  }
+  sqlite3ExprListDelete(db, pList);
+  sqlite3SrcListDelete(db, pTblName);
+  sqlite3DbFree(db, zName);
+  return pRet;
+}
+
+/*
+** Fill the Index.aiRowEst[] array with default information - information
+** to be used when we have not run the ANALYZE command.
+**
+** aiRowEst[0] is suppose to contain the number of elements in the index.
+** Since we do not know, guess 1 million.  aiRowEst[1] is an estimate of the
+** number of rows in the table that match any particular value of the
+** first column of the index.  aiRowEst[2] is an estimate of the number
+** of rows that match any particular combiniation of the first 2 columns
+** of the index.  And so forth.  It must always be the case that
+*
+**           aiRowEst[N]<=aiRowEst[N-1]
+**           aiRowEst[N]>=1
+**
+** Apart from that, we have little to go on besides intuition as to
+** how aiRowEst[] should be initialized.  The numbers generated here
+** are based on typical values found in actual indices.
+*/
+SQLITE_PRIVATE void sqlite3DefaultRowEst(Index *pIdx){
+  unsigned *a = pIdx->aiRowEst;
+  int i;
+  assert( a!=0 );
+  a[0] = 1000000;
+  for(i=pIdx->nColumn; i>=5; i--){
+    a[i] = 5;
+  }
+  while( i>=1 ){
+    a[i] = 11 - i;
+    i--;
+  }
+  if( pIdx->onError!=OE_None ){
+    a[pIdx->nColumn] = 1;
+  }
+}
+
+/*
+** This routine will drop an existing named index.  This routine
+** implements the DROP INDEX statement.
+*/
+SQLITE_PRIVATE void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
+  Index *pIndex;
+  Vdbe *v;
+  sqlite3 *db = pParse->db;
+  int iDb;
+
+  assert( pParse->nErr==0 );   /* Never called with prior errors */
+  if( db->mallocFailed ){
+    goto exit_drop_index;
+  }
+  assert( pName->nSrc==1 );
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    goto exit_drop_index;
+  }
+  pIndex = sqlite3FindIndex(db, pName->a[0].zName, pName->a[0].zDatabase);
+  if( pIndex==0 ){
+    if( !ifExists ){
+      sqlite3ErrorMsg(pParse, "no such index: %S", pName, 0);
+    }
+    pParse->checkSchema = 1;
+    goto exit_drop_index;
+  }
+  if( pIndex->autoIndex ){
+    sqlite3ErrorMsg(pParse, "index associated with UNIQUE "
+      "or PRIMARY KEY constraint cannot be dropped", 0);
+    goto exit_drop_index;
+  }
+  iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  {
+    int code = SQLITE_DROP_INDEX;
+    Table *pTab = pIndex->pTable;
+    const char *zDb = db->aDb[iDb].zName;
+    const char *zTab = SCHEMA_TABLE(iDb);
+    if( sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
+      goto exit_drop_index;
+    }
+    if( !OMIT_TEMPDB && iDb ) code = SQLITE_DROP_TEMP_INDEX;
+    if( sqlite3AuthCheck(pParse, code, pIndex->zName, pTab->zName, zDb) ){
+      goto exit_drop_index;
+    }
+  }
+#endif
+
+  /* Generate code to remove the index and from the master table */
+  v = sqlite3GetVdbe(pParse);
+  if( v ){
+    sqlite3BeginWriteOperation(pParse, 1, iDb);
+    sqlite3NestedParse(pParse,
+       "DELETE FROM %Q.%s WHERE name=%Q",
+       db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
+       pIndex->zName
+    );
+    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
+      sqlite3NestedParse(pParse,
+        "DELETE FROM %Q.sqlite_stat1 WHERE idx=%Q",
+        db->aDb[iDb].zName, pIndex->zName
+      );
+    }
+    sqlite3ChangeCookie(pParse, iDb);
+    destroyRootPage(pParse, pIndex->tnum, iDb);
+    sqlite3VdbeAddOp4(v, OP_DropIndex, iDb, 0, 0, pIndex->zName, 0);
+  }
+
+exit_drop_index:
+  sqlite3SrcListDelete(db, pName);
+}
+
+/*
+** pArray is a pointer to an array of objects.  Each object in the
+** array is szEntry bytes in size.  This routine allocates a new
+** object on the end of the array.
+**
+** *pnEntry is the number of entries already in use.  *pnAlloc is
+** the previously allocated size of the array.  initSize is the
+** suggested initial array size allocation.
+**
+** The index of the new entry is returned in *pIdx.
+**
+** This routine returns a pointer to the array of objects.  This
+** might be the same as the pArray parameter or it might be a different
+** pointer if the array was resized.
+*/
+SQLITE_PRIVATE void *sqlite3ArrayAllocate(
+  sqlite3 *db,      /* Connection to notify of malloc failures */
+  void *pArray,     /* Array of objects.  Might be reallocated */
+  int szEntry,      /* Size of each object in the array */
+  int initSize,     /* Suggested initial allocation, in elements */
+  int *pnEntry,     /* Number of objects currently in use */
+  int *pnAlloc,     /* Current size of the allocation, in elements */
+  int *pIdx         /* Write the index of a new slot here */
+){
+  char *z;
+  if( *pnEntry >= *pnAlloc ){
+    void *pNew;
+    int newSize;
+    newSize = (*pnAlloc)*2 + initSize;
+    pNew = sqlite3DbRealloc(db, pArray, newSize*szEntry);
+    if( pNew==0 ){
+      *pIdx = -1;
+      return pArray;
+    }
+    *pnAlloc = sqlite3DbMallocSize(db, pNew)/szEntry;
+    pArray = pNew;
+  }
+  z = (char*)pArray;
+  memset(&z[*pnEntry * szEntry], 0, szEntry);
+  *pIdx = *pnEntry;
+  ++*pnEntry;
+  return pArray;
+}
+
+/*
+** Append a new element to the given IdList.  Create a new IdList if
+** need be.
+**
+** A new IdList is returned, or NULL if malloc() fails.
+*/
+SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3 *db, IdList *pList, Token *pToken){
+  int i;
+  if( pList==0 ){
+    pList = sqlite3DbMallocZero(db, sizeof(IdList) );
+    if( pList==0 ) return 0;
+    pList->nAlloc = 0;
+  }
+  pList->a = sqlite3ArrayAllocate(
+      db,
+      pList->a,
+      sizeof(pList->a[0]),
+      5,
+      &pList->nId,
+      &pList->nAlloc,
+      &i
+  );
+  if( i<0 ){
+    sqlite3IdListDelete(db, pList);
+    return 0;
+  }
+  pList->a[i].zName = sqlite3NameFromToken(db, pToken);
+  return pList;
+}
+
+/*
+** Delete an IdList.
+*/
+SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3 *db, IdList *pList){
+  int i;
+  if( pList==0 ) return;
+  for(i=0; i<pList->nId; i++){
+    sqlite3DbFree(db, pList->a[i].zName);
+  }
+  sqlite3DbFree(db, pList->a);
+  sqlite3DbFree(db, pList);
+}
+
+/*
+** Return the index in pList of the identifier named zId.  Return -1
+** if not found.
+*/
+SQLITE_PRIVATE int sqlite3IdListIndex(IdList *pList, const char *zName){
+  int i;
+  if( pList==0 ) return -1;
+  for(i=0; i<pList->nId; i++){
+    if( sqlite3StrICmp(pList->a[i].zName, zName)==0 ) return i;
+  }
+  return -1;
+}
+
+/*
+** Expand the space allocated for the given SrcList object by
+** creating nExtra new slots beginning at iStart.  iStart is zero based.
+** New slots are zeroed.
+**
+** For example, suppose a SrcList initially contains two entries: A,B.
+** To append 3 new entries onto the end, do this:
+**
+**    sqlite3SrcListEnlarge(db, pSrclist, 3, 2);
+**
+** After the call above it would contain:  A, B, nil, nil, nil.
+** If the iStart argument had been 1 instead of 2, then the result
+** would have been:  A, nil, nil, nil, B.  To prepend the new slots,
+** the iStart value would be 0.  The result then would
+** be: nil, nil, nil, A, B.
+**
+** If a memory allocation fails the SrcList is unchanged.  The
+** db->mallocFailed flag will be set to true.
+*/
+SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(
+  sqlite3 *db,       /* Database connection to notify of OOM errors */
+  SrcList *pSrc,     /* The SrcList to be enlarged */
+  int nExtra,        /* Number of new slots to add to pSrc->a[] */
+  int iStart         /* Index in pSrc->a[] of first new slot */
+){
+  int i;
+
+  /* Sanity checking on calling parameters */
+  assert( iStart>=0 );
+  assert( nExtra>=1 );
+  assert( pSrc!=0 );
+  assert( iStart<=pSrc->nSrc );
+
+  /* Allocate additional space if needed */
+  if( pSrc->nSrc+nExtra>pSrc->nAlloc ){
+    SrcList *pNew;
+    int nAlloc = pSrc->nSrc+nExtra;
+    int nGot;
+    pNew = sqlite3DbRealloc(db, pSrc,
+               sizeof(*pSrc) + (nAlloc-1)*sizeof(pSrc->a[0]) );
+    if( pNew==0 ){
+      assert( db->mallocFailed );
+      return pSrc;
+    }
+    pSrc = pNew;
+    nGot = (sqlite3DbMallocSize(db, pNew) - sizeof(*pSrc))/sizeof(pSrc->a[0])+1;
+    pSrc->nAlloc = (u16)nGot;
+  }
+
+  /* Move existing slots that come after the newly inserted slots
+  ** out of the way */
+  for(i=pSrc->nSrc-1; i>=iStart; i--){
+    pSrc->a[i+nExtra] = pSrc->a[i];
+  }
+  pSrc->nSrc += (i16)nExtra;
+
+  /* Zero the newly allocated slots */
+  memset(&pSrc->a[iStart], 0, sizeof(pSrc->a[0])*nExtra);
+  for(i=iStart; i<iStart+nExtra; i++){
+    pSrc->a[i].iCursor = -1;
+  }
+
+  /* Return a pointer to the enlarged SrcList */
+  return pSrc;
+}
+
+
+/*
+** Append a new table name to the given SrcList.  Create a new SrcList if
+** need be.  A new entry is created in the SrcList even if pTable is NULL.
+**
+** A SrcList is returned, or NULL if there is an OOM error.  The returned
+** SrcList might be the same as the SrcList that was input or it might be
+** a new one.  If an OOM error does occurs, then the prior value of pList
+** that is input to this routine is automatically freed.
+**
+** If pDatabase is not null, it means that the table has an optional
+** database name prefix.  Like this:  "database.table".  The pDatabase
+** points to the table name and the pTable points to the database name.
+** The SrcList.a[].zName field is filled with the table name which might
+** come from pTable (if pDatabase is NULL) or from pDatabase.  
+** SrcList.a[].zDatabase is filled with the database name from pTable,
+** or with NULL if no database is specified.
+**
+** In other words, if call like this:
+**
+**         sqlite3SrcListAppend(D,A,B,0);
+**
+** Then B is a table name and the database name is unspecified.  If called
+** like this:
+**
+**         sqlite3SrcListAppend(D,A,B,C);
+**
+** Then C is the table name and B is the database name.  If C is defined
+** then so is B.  In other words, we never have a case where:
+**
+**         sqlite3SrcListAppend(D,A,0,C);
+**
+** Both pTable and pDatabase are assumed to be quoted.  They are dequoted
+** before being added to the SrcList.
+*/
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(
+  sqlite3 *db,        /* Connection to notify of malloc failures */
+  SrcList *pList,     /* Append to this SrcList. NULL creates a new SrcList */
+  Token *pTable,      /* Table to append */
+  Token *pDatabase    /* Database of the table */
+){
+  struct SrcList_item *pItem;
+  assert( pDatabase==0 || pTable!=0 );  /* Cannot have C without B */
+  if( pList==0 ){
+    pList = sqlite3DbMallocZero(db, sizeof(SrcList) );
+    if( pList==0 ) return 0;
+    pList->nAlloc = 1;
+  }
+  pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
+  if( db->mallocFailed ){
+    sqlite3SrcListDelete(db, pList);
+    return 0;
+  }
+  pItem = &pList->a[pList->nSrc-1];
+  if( pDatabase && pDatabase->z==0 ){
+    pDatabase = 0;
+  }
+  if( pDatabase ){
+    Token *pTemp = pDatabase;
+    pDatabase = pTable;
+    pTable = pTemp;
+  }
+  pItem->zName = sqlite3NameFromToken(db, pTable);
+  pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
+  return pList;
+}
+
+/*
+** Assign VdbeCursor index numbers to all tables in a SrcList
+*/
+SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
+  int i;
+  struct SrcList_item *pItem;
+  assert(pList || pParse->db->mallocFailed );
+  if( pList ){
+    for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
+      if( pItem->iCursor>=0 ) break;
+      pItem->iCursor = pParse->nTab++;
+      if( pItem->pSelect ){
+        sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
+      }
+    }
+  }
+}
+
+/*
+** Delete an entire SrcList including all its substructure.
+*/
+SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3 *db, SrcList *pList){
+  int i;
+  struct SrcList_item *pItem;
+  if( pList==0 ) return;
+  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
+    sqlite3DbFree(db, pItem->zDatabase);
+    sqlite3DbFree(db, pItem->zName);
+    sqlite3DbFree(db, pItem->zAlias);
+    sqlite3DbFree(db, pItem->zIndex);
+    sqlite3DeleteTable(pItem->pTab);
+    sqlite3SelectDelete(db, pItem->pSelect);
+    sqlite3ExprDelete(db, pItem->pOn);
+    sqlite3IdListDelete(db, pItem->pUsing);
+  }
+  sqlite3DbFree(db, pList);
+}
+
+/*
+** This routine is called by the parser to add a new term to the
+** end of a growing FROM clause.  The "p" parameter is the part of
+** the FROM clause that has already been constructed.  "p" is NULL
+** if this is the first term of the FROM clause.  pTable and pDatabase
+** are the name of the table and database named in the FROM clause term.
+** pDatabase is NULL if the database name qualifier is missing - the
+** usual case.  If the term has a alias, then pAlias points to the
+** alias token.  If the term is a subquery, then pSubquery is the
+** SELECT statement that the subquery encodes.  The pTable and
+** pDatabase parameters are NULL for subqueries.  The pOn and pUsing
+** parameters are the content of the ON and USING clauses.
+**
+** Return a new SrcList which encodes is the FROM with the new
+** term added.
+*/
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(
+  Parse *pParse,          /* Parsing context */
+  SrcList *p,             /* The left part of the FROM clause already seen */
+  Token *pTable,          /* Name of the table to add to the FROM clause */
+  Token *pDatabase,       /* Name of the database containing pTable */
+  Token *pAlias,          /* The right-hand side of the AS subexpression */
+  Select *pSubquery,      /* A subquery used in place of a table name */
+  Expr *pOn,              /* The ON clause of a join */
+  IdList *pUsing          /* The USING clause of a join */
+){
+  struct SrcList_item *pItem;
+  sqlite3 *db = pParse->db;
+  if( !p && (pOn || pUsing) ){
+    sqlite3ErrorMsg(pParse, "a JOIN clause is required before %s", 
+      (pOn ? "ON" : "USING")
+    );
+    goto append_from_error;
+  }
+  p = sqlite3SrcListAppend(db, p, pTable, pDatabase);
+  if( p==0 || NEVER(p->nSrc==0) ){
+    goto append_from_error;
+  }
+  pItem = &p->a[p->nSrc-1];
+  assert( pAlias!=0 );
+  if( pAlias->n ){
+    pItem->zAlias = sqlite3NameFromToken(db, pAlias);
+  }
+  pItem->pSelect = pSubquery;
+  pItem->pOn = pOn;
+  pItem->pUsing = pUsing;
+  return p;
+
+ append_from_error:
+  assert( p==0 );
+  sqlite3ExprDelete(db, pOn);
+  sqlite3IdListDelete(db, pUsing);
+  sqlite3SelectDelete(db, pSubquery);
+  return 0;
+}
+
+/*
+** Add an INDEXED BY or NOT INDEXED clause to the most recently added 
+** element of the source-list passed as the second argument.
+*/
+SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *pParse, SrcList *p, Token *pIndexedBy){
+  assert( pIndexedBy!=0 );
+  if( p && ALWAYS(p->nSrc>0) ){
+    struct SrcList_item *pItem = &p->a[p->nSrc-1];
+    assert( pItem->notIndexed==0 && pItem->zIndex==0 );
+    if( pIndexedBy->n==1 && !pIndexedBy->z ){
+      /* A "NOT INDEXED" clause was supplied. See parse.y 
+      ** construct "indexed_opt" for details. */
+      pItem->notIndexed = 1;
+    }else{
+      pItem->zIndex = sqlite3NameFromToken(pParse->db, pIndexedBy);
+    }
+  }
+}
+
+/*
+** When building up a FROM clause in the parser, the join operator
+** is initially attached to the left operand.  But the code generator
+** expects the join operator to be on the right operand.  This routine
+** Shifts all join operators from left to right for an entire FROM
+** clause.
+**
+** Example: Suppose the join is like this:
+**
+**           A natural cross join B
+**
+** The operator is "natural cross join".  The A and B operands are stored
+** in p->a[0] and p->a[1], respectively.  The parser initially stores the
+** operator with A.  This routine shifts that operator over to B.
+*/
+SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList *p){
+  if( p && p->a ){
+    int i;
+    for(i=p->nSrc-1; i>0; i--){
+      p->a[i].jointype = p->a[i-1].jointype;
+    }
+    p->a[0].jointype = 0;
+  }
+}
+
+/*
+** Begin a transaction
+*/
+SQLITE_PRIVATE void sqlite3BeginTransaction(Parse *pParse, int type){
+  sqlite3 *db;
+  Vdbe *v;
+  int i;
+
+  assert( pParse!=0 );
+  db = pParse->db;
+  assert( db!=0 );
+/*  if( db->aDb[0].pBt==0 ) return; */
+  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "BEGIN", 0, 0) ){
+    return;
+  }
+  v = sqlite3GetVdbe(pParse);
+  if( !v ) return;
+  if( type!=TK_DEFERRED ){
+    for(i=0; i<db->nDb; i++){
+      sqlite3VdbeAddOp2(v, OP_Transaction, i, (type==TK_EXCLUSIVE)+1);
+      sqlite3VdbeUsesBtree(v, i);
+    }
+  }
+  sqlite3VdbeAddOp2(v, OP_AutoCommit, 0, 0);
+}
+
+/*
+** Commit a transaction
+*/
+SQLITE_PRIVATE void sqlite3CommitTransaction(Parse *pParse){
+  sqlite3 *db;
+  Vdbe *v;
+
+  assert( pParse!=0 );
+  db = pParse->db;
+  assert( db!=0 );
+/*  if( db->aDb[0].pBt==0 ) return; */
+  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "COMMIT", 0, 0) ){
+    return;
+  }
+  v = sqlite3GetVdbe(pParse);
+  if( v ){
+    sqlite3VdbeAddOp2(v, OP_AutoCommit, 1, 0);
+  }
+}
+
+/*
+** Rollback a transaction
+*/
+SQLITE_PRIVATE void sqlite3RollbackTransaction(Parse *pParse){
+  sqlite3 *db;
+  Vdbe *v;
+
+  assert( pParse!=0 );
+  db = pParse->db;
+  assert( db!=0 );
+/*  if( db->aDb[0].pBt==0 ) return; */
+  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "ROLLBACK", 0, 0) ){
+    return;
+  }
+  v = sqlite3GetVdbe(pParse);
+  if( v ){
+    sqlite3VdbeAddOp2(v, OP_AutoCommit, 1, 1);
+  }
+}
+
+/*
+** This function is called by the parser when it parses a command to create,
+** release or rollback an SQL savepoint. 
+*/
+SQLITE_PRIVATE void sqlite3Savepoint(Parse *pParse, int op, Token *pName){
+  char *zName = sqlite3NameFromToken(pParse->db, pName);
+  if( zName ){
+    Vdbe *v = sqlite3GetVdbe(pParse);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+    static const char *az[] = { "BEGIN", "RELEASE", "ROLLBACK" };
+    assert( !SAVEPOINT_BEGIN && SAVEPOINT_RELEASE==1 && SAVEPOINT_ROLLBACK==2 );
+#endif
+    if( !v || sqlite3AuthCheck(pParse, SQLITE_SAVEPOINT, az[op], zName, 0) ){
+      sqlite3DbFree(pParse->db, zName);
+      return;
+    }
+    sqlite3VdbeAddOp4(v, OP_Savepoint, op, 0, 0, zName, P4_DYNAMIC);
+  }
+}
+
+/*
+** Make sure the TEMP database is open and available for use.  Return
+** the number of errors.  Leave any error messages in the pParse structure.
+*/
+SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *pParse){
+  sqlite3 *db = pParse->db;
+  if( db->aDb[1].pBt==0 && !pParse->explain ){
+    int rc;
+    static const int flags = 
+          SQLITE_OPEN_READWRITE |
+          SQLITE_OPEN_CREATE |
+          SQLITE_OPEN_EXCLUSIVE |
+          SQLITE_OPEN_DELETEONCLOSE |
+          SQLITE_OPEN_TEMP_DB;
+
+    rc = sqlite3BtreeFactory(db, 0, 0, SQLITE_DEFAULT_CACHE_SIZE, flags,
+                                 &db->aDb[1].pBt);
+    if( rc!=SQLITE_OK ){
+      sqlite3ErrorMsg(pParse, "unable to open a temporary database "
+        "file for storing temporary tables");
+      pParse->rc = rc;
+      return 1;
+    }
+    assert( (db->flags & SQLITE_InTrans)==0 || db->autoCommit );
+    assert( db->aDb[1].pSchema );
+    sqlite3PagerJournalMode(sqlite3BtreePager(db->aDb[1].pBt),
+                            db->dfltJournalMode);
+  }
+  return 0;
+}
+
+/*
+** Generate VDBE code that will verify the schema cookie and start
+** a read-transaction for all named database files.
+**
+** It is important that all schema cookies be verified and all
+** read transactions be started before anything else happens in
+** the VDBE program.  But this routine can be called after much other
+** code has been generated.  So here is what we do:
+**
+** The first time this routine is called, we code an OP_Goto that
+** will jump to a subroutine at the end of the program.  Then we
+** record every database that needs its schema verified in the
+** pParse->cookieMask field.  Later, after all other code has been
+** generated, the subroutine that does the cookie verifications and
+** starts the transactions will be coded and the OP_Goto P2 value
+** will be made to point to that subroutine.  The generation of the
+** cookie verification subroutine code happens in sqlite3FinishCoding().
+**
+** If iDb<0 then code the OP_Goto only - don't set flag to verify the
+** schema on any databases.  This can be used to position the OP_Goto
+** early in the code, before we know if any database tables will be used.
+*/
+SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse *pParse, int iDb){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
+
+  if( pToplevel->cookieGoto==0 ){
+    Vdbe *v = sqlite3GetVdbe(pToplevel);
+    if( v==0 ) return;  /* This only happens if there was a prior error */
+    pToplevel->cookieGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0)+1;
+  }
+  if( iDb>=0 ){
+    sqlite3 *db = pToplevel->db;
+    int mask;
+
+    assert( iDb<db->nDb );
+    assert( db->aDb[iDb].pBt!=0 || iDb==1 );
+    assert( iDb<SQLITE_MAX_ATTACHED+2 );
+    mask = 1<<iDb;
+    if( (pToplevel->cookieMask & mask)==0 ){
+      pToplevel->cookieMask |= mask;
+      pToplevel->cookieValue[iDb] = db->aDb[iDb].pSchema->schema_cookie;
+      if( !OMIT_TEMPDB && iDb==1 ){
+        sqlite3OpenTempDatabase(pToplevel);
+      }
+    }
+  }
+}
+
+/*
+** Generate VDBE code that prepares for doing an operation that
+** might change the database.
+**
+** This routine starts a new transaction if we are not already within
+** a transaction.  If we are already within a transaction, then a checkpoint
+** is set if the setStatement parameter is true.  A checkpoint should
+** be set for operations that might fail (due to a constraint) part of
+** the way through and which will need to undo some writes without having to
+** rollback the whole transaction.  For operations where all constraints
+** can be checked before any changes are made to the database, it is never
+** necessary to undo a write and the checkpoint should not be set.
+*/
+SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse *pParse, int setStatement, int iDb){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
+  sqlite3CodeVerifySchema(pParse, iDb);
+  pToplevel->writeMask |= 1<<iDb;
+  pToplevel->isMultiWrite |= setStatement;
+}
+
+/*
+** Indicate that the statement currently under construction might write
+** more than one entry (example: deleting one row then inserting another,
+** inserting multiple rows in a table, or inserting a row and index entries.)
+** If an abort occurs after some of these writes have completed, then it will
+** be necessary to undo the completed writes.
+*/
+SQLITE_PRIVATE void sqlite3MultiWrite(Parse *pParse){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
+  pToplevel->isMultiWrite = 1;
+}
+
+/* 
+** The code generator calls this routine if is discovers that it is
+** possible to abort a statement prior to completion.  In order to 
+** perform this abort without corrupting the database, we need to make
+** sure that the statement is protected by a statement transaction.
+**
+** Technically, we only need to set the mayAbort flag if the
+** isMultiWrite flag was previously set.  There is a time dependency
+** such that the abort must occur after the multiwrite.  This makes
+** some statements involving the REPLACE conflict resolution algorithm
+** go a little faster.  But taking advantage of this time dependency
+** makes it more difficult to prove that the code is correct (in 
+** particular, it prevents us from writing an effective
+** implementation of sqlite3AssertMayAbort()) and so we have chosen
+** to take the safe route and skip the optimization.
+*/
+SQLITE_PRIVATE void sqlite3MayAbort(Parse *pParse){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
+  pToplevel->mayAbort = 1;
+}
+
+/*
+** Code an OP_Halt that causes the vdbe to return an SQLITE_CONSTRAINT
+** error. The onError parameter determines which (if any) of the statement
+** and/or current transaction is rolled back.
+*/
+SQLITE_PRIVATE void sqlite3HaltConstraint(Parse *pParse, int onError, char *p4, int p4type){
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( onError==OE_Abort ){
+    sqlite3MayAbort(pParse);
+  }
+  sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0, p4, p4type);
+}
+
+/*
+** Check to see if pIndex uses the collating sequence pColl.  Return
+** true if it does and false if it does not.
+*/
+#ifndef SQLITE_OMIT_REINDEX
+static int collationMatch(const char *zColl, Index *pIndex){
+  int i;
+  assert( zColl!=0 );
+  for(i=0; i<pIndex->nColumn; i++){
+    const char *z = pIndex->azColl[i];
+    assert( z!=0 );
+    if( 0==sqlite3StrICmp(z, zColl) ){
+      return 1;
+    }
+  }
+  return 0;
+}
+#endif
+
+/*
+** Recompute all indices of pTab that use the collating sequence pColl.
+** If pColl==0 then recompute all indices of pTab.
+*/
+#ifndef SQLITE_OMIT_REINDEX
+static void reindexTable(Parse *pParse, Table *pTab, char const *zColl){
+  Index *pIndex;              /* An index associated with pTab */
+
+  for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
+    if( zColl==0 || collationMatch(zColl, pIndex) ){
+      int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+      sqlite3BeginWriteOperation(pParse, 0, iDb);
+      sqlite3RefillIndex(pParse, pIndex, -1);
+    }
+  }
+}
+#endif
+
+/*
+** Recompute all indices of all tables in all databases where the
+** indices use the collating sequence pColl.  If pColl==0 then recompute
+** all indices everywhere.
+*/
+#ifndef SQLITE_OMIT_REINDEX
+static void reindexDatabases(Parse *pParse, char const *zColl){
+  Db *pDb;                    /* A single database */
+  int iDb;                    /* The database index number */
+  sqlite3 *db = pParse->db;   /* The database connection */
+  HashElem *k;                /* For looping over tables in pDb */
+  Table *pTab;                /* A table in the database */
+
+  for(iDb=0, pDb=db->aDb; iDb<db->nDb; iDb++, pDb++){
+    assert( pDb!=0 );
+    for(k=sqliteHashFirst(&pDb->pSchema->tblHash);  k; k=sqliteHashNext(k)){
+      pTab = (Table*)sqliteHashData(k);
+      reindexTable(pParse, pTab, zColl);
+    }
+  }
+}
+#endif
+
+/*
+** Generate code for the REINDEX command.
+**
+**        REINDEX                            -- 1
+**        REINDEX  <collation>               -- 2
+**        REINDEX  ?<database>.?<tablename>  -- 3
+**        REINDEX  ?<database>.?<indexname>  -- 4
+**
+** Form 1 causes all indices in all attached databases to be rebuilt.
+** Form 2 rebuilds all indices in all databases that use the named
+** collating function.  Forms 3 and 4 rebuild the named index or all
+** indices associated with the named table.
+*/
+#ifndef SQLITE_OMIT_REINDEX
+SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
+  CollSeq *pColl;             /* Collating sequence to be reindexed, or NULL */
+  char *z;                    /* Name of a table or index */
+  const char *zDb;            /* Name of the database */
+  Table *pTab;                /* A table in the database */
+  Index *pIndex;              /* An index associated with pTab */
+  int iDb;                    /* The database index number */
+  sqlite3 *db = pParse->db;   /* The database connection */
+  Token *pObjName;            /* Name of the table or index to be reindexed */
+
+  /* Read the database schema. If an error occurs, leave an error message
+  ** and code in pParse and return NULL. */
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    return;
+  }
+
+  if( pName1==0 ){
+    reindexDatabases(pParse, 0);
+    return;
+  }else if( NEVER(pName2==0) || pName2->z==0 ){
+    char *zColl;
+    assert( pName1->z );
+    zColl = sqlite3NameFromToken(pParse->db, pName1);
+    if( !zColl ) return;
+    pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
+    if( pColl ){
+      reindexDatabases(pParse, zColl);
+      sqlite3DbFree(db, zColl);
+      return;
+    }
+    sqlite3DbFree(db, zColl);
+  }
+  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
+  if( iDb<0 ) return;
+  z = sqlite3NameFromToken(db, pObjName);
+  if( z==0 ) return;
+  zDb = db->aDb[iDb].zName;
+  pTab = sqlite3FindTable(db, z, zDb);
+  if( pTab ){
+    reindexTable(pParse, pTab, 0);
+    sqlite3DbFree(db, z);
+    return;
+  }
+  pIndex = sqlite3FindIndex(db, z, zDb);
+  sqlite3DbFree(db, z);
+  if( pIndex ){
+    sqlite3BeginWriteOperation(pParse, 0, iDb);
+    sqlite3RefillIndex(pParse, pIndex, -1);
+    return;
+  }
+  sqlite3ErrorMsg(pParse, "unable to identify the object to be reindexed");
+}
+#endif
+
+/*
+** Return a dynamicly allocated KeyInfo structure that can be used
+** with OP_OpenRead or OP_OpenWrite to access database index pIdx.
+**
+** If successful, a pointer to the new structure is returned. In this case
+** the caller is responsible for calling sqlite3DbFree(db, ) on the returned 
+** pointer. If an error occurs (out of memory or missing collation 
+** sequence), NULL is returned and the state of pParse updated to reflect
+** the error.
+*/
+SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
+  int i;
+  int nCol = pIdx->nColumn;
+  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
+  sqlite3 *db = pParse->db;
+  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZero(db, nBytes);
+
+  if( pKey ){
+    pKey->db = pParse->db;
+    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
+    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );
+    for(i=0; i<nCol; i++){
+      char *zColl = pIdx->azColl[i];
+      assert( zColl );
+      pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl);
+      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
+    }
+    pKey->nField = (u16)nCol;
+  }
+
+  if( pParse->nErr ){
+    sqlite3DbFree(db, pKey);
+    pKey = 0;
+  }
+  return pKey;
+}
+
+/************** End of build.c ***********************************************/
+/************** Begin file callback.c ****************************************/
+/*
+** 2005 May 23 
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains functions used to access the internal hash tables
+** of user defined functions and collation sequences.
+**
+** $Id: callback.c,v 1.42 2009/06/17 00:35:31 drh Exp $
+*/
+
+
+/*
+** Invoke the 'collation needed' callback to request a collation sequence
+** in the encoding enc of name zName, length nName.
+*/
+static void callCollNeeded(sqlite3 *db, int enc, const char *zName){
+  assert( !db->xCollNeeded || !db->xCollNeeded16 );
+  if( db->xCollNeeded ){
+    char *zExternal = sqlite3DbStrDup(db, zName);
+    if( !zExternal ) return;
+    db->xCollNeeded(db->pCollNeededArg, db, enc, zExternal);
+    sqlite3DbFree(db, zExternal);
+  }
+#ifndef SQLITE_OMIT_UTF16
+  if( db->xCollNeeded16 ){
+    char const *zExternal;
+    sqlite3_value *pTmp = sqlite3ValueNew(db);
+    sqlite3ValueSetStr(pTmp, -1, zName, SQLITE_UTF8, SQLITE_STATIC);
+    zExternal = sqlite3ValueText(pTmp, SQLITE_UTF16NATIVE);
+    if( zExternal ){
+      db->xCollNeeded16(db->pCollNeededArg, db, (int)ENC(db), zExternal);
+    }
+    sqlite3ValueFree(pTmp);
+  }
+#endif
+}
+
+/*
+** This routine is called if the collation factory fails to deliver a
+** collation function in the best encoding but there may be other versions
+** of this collation function (for other text encodings) available. Use one
+** of these instead if they exist. Avoid a UTF-8 <-> UTF-16 conversion if
+** possible.
+*/
+static int synthCollSeq(sqlite3 *db, CollSeq *pColl){
+  CollSeq *pColl2;
+  char *z = pColl->zName;
+  int i;
+  static const u8 aEnc[] = { SQLITE_UTF16BE, SQLITE_UTF16LE, SQLITE_UTF8 };
+  for(i=0; i<3; i++){
+    pColl2 = sqlite3FindCollSeq(db, aEnc[i], z, 0);
+    if( pColl2->xCmp!=0 ){
+      memcpy(pColl, pColl2, sizeof(CollSeq));
+      pColl->xDel = 0;         /* Do not copy the destructor */
+      return SQLITE_OK;
+    }
+  }
+  return SQLITE_ERROR;
+}
+
+/*
+** This function is responsible for invoking the collation factory callback
+** or substituting a collation sequence of a different encoding when the
+** requested collation sequence is not available in the desired encoding.
+** 
+** If it is not NULL, then pColl must point to the database native encoding 
+** collation sequence with name zName, length nName.
+**
+** The return value is either the collation sequence to be used in database
+** db for collation type name zName, length nName, or NULL, if no collation
+** sequence can be found.
+**
+** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
+*/
+SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(
+  sqlite3* db,          /* The database connection */
+  u8 enc,               /* The desired encoding for the collating sequence */
+  CollSeq *pColl,       /* Collating sequence with native encoding, or NULL */
+  const char *zName     /* Collating sequence name */
+){
+  CollSeq *p;
+
+  p = pColl;
+  if( !p ){
+    p = sqlite3FindCollSeq(db, enc, zName, 0);
+  }
+  if( !p || !p->xCmp ){
+    /* No collation sequence of this type for this encoding is registered.
+    ** Call the collation factory to see if it can supply us with one.
+    */
+    callCollNeeded(db, enc, zName);
+    p = sqlite3FindCollSeq(db, enc, zName, 0);
+  }
+  if( p && !p->xCmp && synthCollSeq(db, p) ){
+    p = 0;
+  }
+  assert( !p || p->xCmp );
+  return p;
+}
+
+/*
+** This routine is called on a collation sequence before it is used to
+** check that it is defined. An undefined collation sequence exists when
+** a database is loaded that contains references to collation sequences
+** that have not been defined by sqlite3_create_collation() etc.
+**
+** If required, this routine calls the 'collation needed' callback to
+** request a definition of the collating sequence. If this doesn't work, 
+** an equivalent collating sequence that uses a text encoding different
+** from the main database is substituted, if one is available.
+*/
+SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *pParse, CollSeq *pColl){
+  if( pColl ){
+    const char *zName = pColl->zName;
+    sqlite3 *db = pParse->db;
+    CollSeq *p = sqlite3GetCollSeq(db, ENC(db), pColl, zName);
+    if( !p ){
+      sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
+      pParse->nErr++;
+      return SQLITE_ERROR;
+    }
+    assert( p==pColl );
+  }
+  return SQLITE_OK;
+}
+
+
+
+/*
+** Locate and return an entry from the db.aCollSeq hash table. If the entry
+** specified by zName and nName is not found and parameter 'create' is
+** true, then create a new entry. Otherwise return NULL.
+**
+** Each pointer stored in the sqlite3.aCollSeq hash table contains an
+** array of three CollSeq structures. The first is the collation sequence
+** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
+**
+** Stored immediately after the three collation sequences is a copy of
+** the collation sequence name. A pointer to this string is stored in
+** each collation sequence structure.
+*/
+static CollSeq *findCollSeqEntry(
+  sqlite3 *db,          /* Database connection */
+  const char *zName,    /* Name of the collating sequence */
+  int create            /* Create a new entry if true */
+){
+  CollSeq *pColl;
+  int nName = sqlite3Strlen30(zName);
+  pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
+
+  if( 0==pColl && create ){
+    pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
+    if( pColl ){
+      CollSeq *pDel = 0;
+      pColl[0].zName = (char*)&pColl[3];
+      pColl[0].enc = SQLITE_UTF8;
+      pColl[1].zName = (char*)&pColl[3];
+      pColl[1].enc = SQLITE_UTF16LE;
+      pColl[2].zName = (char*)&pColl[3];
+      pColl[2].enc = SQLITE_UTF16BE;
+      memcpy(pColl[0].zName, zName, nName);
+      pColl[0].zName[nName] = 0;
+      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);
+
+      /* If a malloc() failure occurred in sqlite3HashInsert(), it will 
+      ** return the pColl pointer to be deleted (because it wasn't added
+      ** to the hash table).
+      */
+      assert( pDel==0 || pDel==pColl );
+      if( pDel!=0 ){
+        db->mallocFailed = 1;
+        sqlite3DbFree(db, pDel);
+        pColl = 0;
+      }
+    }
+  }
+  return pColl;
+}
+
+/*
+** Parameter zName points to a UTF-8 encoded string nName bytes long.
+** Return the CollSeq* pointer for the collation sequence named zName
+** for the encoding 'enc' from the database 'db'.
+**
+** If the entry specified is not found and 'create' is true, then create a
+** new entry.  Otherwise return NULL.
+**
+** A separate function sqlite3LocateCollSeq() is a wrapper around
+** this routine.  sqlite3LocateCollSeq() invokes the collation factory
+** if necessary and generates an error message if the collating sequence
+** cannot be found.
+**
+** See also: sqlite3LocateCollSeq(), sqlite3GetCollSeq()
+*/
+SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(
+  sqlite3 *db,
+  u8 enc,
+  const char *zName,
+  int create
+){
+  CollSeq *pColl;
+  if( zName ){
+    pColl = findCollSeqEntry(db, zName, create);
+  }else{
+    pColl = db->pDfltColl;
+  }
+  assert( SQLITE_UTF8==1 && SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+  assert( enc>=SQLITE_UTF8 && enc<=SQLITE_UTF16BE );
+  if( pColl ) pColl += enc-1;
+  return pColl;
+}
+
+/* During the search for the best function definition, this procedure
+** is called to test how well the function passed as the first argument
+** matches the request for a function with nArg arguments in a system
+** that uses encoding enc. The value returned indicates how well the
+** request is matched. A higher value indicates a better match.
+**
+** The returned value is always between 0 and 6, as follows:
+**
+** 0: Not a match, or if nArg<0 and the function is has no implementation.
+** 1: A variable arguments function that prefers UTF-8 when a UTF-16
+**    encoding is requested, or vice versa.
+** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
+**    requested, or vice versa.
+** 3: A variable arguments function using the same text encoding.
+** 4: A function with the exact number of arguments requested that
+**    prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
+** 5: A function with the exact number of arguments requested that
+**    prefers UTF-16LE when UTF-16BE is requested, or vice versa.
+** 6: An exact match.
+**
+*/
+static int matchQuality(FuncDef *p, int nArg, u8 enc){
+  int match = 0;
+  if( p->nArg==-1 || p->nArg==nArg 
+   || (nArg==-1 && (p->xFunc!=0 || p->xStep!=0))
+  ){
+    match = 1;
+    if( p->nArg==nArg || nArg==-1 ){
+      match = 4;
+    }
+    if( enc==p->iPrefEnc ){
+      match += 2;
+    }
+    else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
+             (enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
+      match += 1;
+    }
+  }
+  return match;
+}
+
+/*
+** Search a FuncDefHash for a function with the given name.  Return
+** a pointer to the matching FuncDef if found, or 0 if there is no match.
+*/
+static FuncDef *functionSearch(
+  FuncDefHash *pHash,  /* Hash table to search */
+  int h,               /* Hash of the name */
+  const char *zFunc,   /* Name of function */
+  int nFunc            /* Number of bytes in zFunc */
+){
+  FuncDef *p;
+  for(p=pHash->a[h]; p; p=p->pHash){
+    if( sqlite3StrNICmp(p->zName, zFunc, nFunc)==0 && p->zName[nFunc]==0 ){
+      return p;
+    }
+  }
+  return 0;
+}
+
+/*
+** Insert a new FuncDef into a FuncDefHash hash table.
+*/
+SQLITE_PRIVATE void sqlite3FuncDefInsert(
+  FuncDefHash *pHash,  /* The hash table into which to insert */
+  FuncDef *pDef        /* The function definition to insert */
+){
+  FuncDef *pOther;
+  int nName = sqlite3Strlen30(pDef->zName);
+  u8 c1 = (u8)pDef->zName[0];
+  int h = (sqlite3UpperToLower[c1] + nName) % ArraySize(pHash->a);
+  pOther = functionSearch(pHash, h, pDef->zName, nName);
+  if( pOther ){
+    assert( pOther!=pDef && pOther->pNext!=pDef );
+    pDef->pNext = pOther->pNext;
+    pOther->pNext = pDef;
+  }else{
+    pDef->pNext = 0;
+    pDef->pHash = pHash->a[h];
+    pHash->a[h] = pDef;
+  }
+}
+  
+  
+
+/*
+** Locate a user function given a name, a number of arguments and a flag
+** indicating whether the function prefers UTF-16 over UTF-8.  Return a
+** pointer to the FuncDef structure that defines that function, or return
+** NULL if the function does not exist.
+**
+** If the createFlag argument is true, then a new (blank) FuncDef
+** structure is created and liked into the "db" structure if a
+** no matching function previously existed.  When createFlag is true
+** and the nArg parameter is -1, then only a function that accepts
+** any number of arguments will be returned.
+**
+** If createFlag is false and nArg is -1, then the first valid
+** function found is returned.  A function is valid if either xFunc
+** or xStep is non-zero.
+**
+** If createFlag is false, then a function with the required name and
+** number of arguments may be returned even if the eTextRep flag does not
+** match that requested.
+*/
+SQLITE_PRIVATE FuncDef *sqlite3FindFunction(
+  sqlite3 *db,       /* An open database */
+  const char *zName, /* Name of the function.  Not null-terminated */
+  int nName,         /* Number of characters in the name */
+  int nArg,          /* Number of arguments.  -1 means any number */
+  u8 enc,            /* Preferred text encoding */
+  int createFlag     /* Create new entry if true and does not otherwise exist */
+){
+  FuncDef *p;         /* Iterator variable */
+  FuncDef *pBest = 0; /* Best match found so far */
+  int bestScore = 0;  /* Score of best match */
+  int h;              /* Hash value */
+
+
+  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+  h = (sqlite3UpperToLower[(u8)zName[0]] + nName) % ArraySize(db->aFunc.a);
+
+  /* First search for a match amongst the application-defined functions.
+  */
+  p = functionSearch(&db->aFunc, h, zName, nName);
+  while( p ){
+    int score = matchQuality(p, nArg, enc);
+    if( score>bestScore ){
+      pBest = p;
+      bestScore = score;
+    }
+    p = p->pNext;
+  }
+
+  /* If no match is found, search the built-in functions.
+  **
+  ** Except, if createFlag is true, that means that we are trying to
+  ** install a new function.  Whatever FuncDef structure is returned will
+  ** have fields overwritten with new information appropriate for the
+  ** new function.  But the FuncDefs for built-in functions are read-only.
+  ** So we must not search for built-ins when creating a new function.
+  */ 
+  if( !createFlag && !pBest ){
+    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+    p = functionSearch(pHash, h, zName, nName);
+    while( p ){
+      int score = matchQuality(p, nArg, enc);
+      if( score>bestScore ){
+        pBest = p;
+        bestScore = score;
+      }
+      p = p->pNext;
+    }
+  }
+
+  /* If the createFlag parameter is true and the search did not reveal an
+  ** exact match for the name, number of arguments and encoding, then add a
+  ** new entry to the hash table and return it.
+  */
+  if( createFlag && (bestScore<6 || pBest->nArg!=nArg) && 
+      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){
+    pBest->zName = (char *)&pBest[1];
+    pBest->nArg = (u16)nArg;
+    pBest->iPrefEnc = enc;
+    memcpy(pBest->zName, zName, nName);
+    pBest->zName[nName] = 0;
+    sqlite3FuncDefInsert(&db->aFunc, pBest);
+  }
+
+  if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
+    return pBest;
+  }
+  return 0;
+}
+
+/*
+** Free all resources held by the schema structure. The void* argument points
+** at a Schema struct. This function does not call sqlite3DbFree(db, ) on the 
+** pointer itself, it just cleans up subsiduary resources (i.e. the contents
+** of the schema hash tables).
+**
+** The Schema.cache_size variable is not cleared.
+*/
+SQLITE_PRIVATE void sqlite3SchemaFree(void *p){
+  Hash temp1;
+  Hash temp2;
+  HashElem *pElem;
+  Schema *pSchema = (Schema *)p;
+
+  temp1 = pSchema->tblHash;
+  temp2 = pSchema->trigHash;
+  sqlite3HashInit(&pSchema->trigHash);
+  sqlite3HashClear(&pSchema->idxHash);
+  for(pElem=sqliteHashFirst(&temp2); pElem; pElem=sqliteHashNext(pElem)){
+    sqlite3DeleteTrigger(0, (Trigger*)sqliteHashData(pElem));
+  }
+  sqlite3HashClear(&temp2);
+  sqlite3HashInit(&pSchema->tblHash);
+  for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
+    Table *pTab = sqliteHashData(pElem);
+    assert( pTab->dbMem==0 );
+    sqlite3DeleteTable(pTab);
+  }
+  sqlite3HashClear(&temp1);
+  sqlite3HashClear(&pSchema->fkeyHash);
+  pSchema->pSeqTab = 0;
+  pSchema->flags &= ~DB_SchemaLoaded;
+}
+
+/*
+** Find and return the schema associated with a BTree.  Create
+** a new one if necessary.
+*/
+SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
+  Schema * p;
+  if( pBt ){
+    p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaFree);
+  }else{
+    p = (Schema *)sqlite3MallocZero(sizeof(Schema));
+  }
+  if( !p ){
+    db->mallocFailed = 1;
+  }else if ( 0==p->file_format ){
+    sqlite3HashInit(&p->tblHash);
+    sqlite3HashInit(&p->idxHash);
+    sqlite3HashInit(&p->trigHash);
+    sqlite3HashInit(&p->fkeyHash);
+    p->enc = SQLITE_UTF8;
+  }
+  return p;
+}
+
+/************** End of callback.c ********************************************/
+/************** Begin file delete.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that are called by the parser
+** in order to generate code for DELETE FROM statements.
+**
+** $Id: delete.c,v 1.207 2009/08/08 18:01:08 drh Exp $
+*/
+
+/*
+** Look up every table that is named in pSrc.  If any table is not found,
+** add an error message to pParse->zErrMsg and return NULL.  If all tables
+** are found, return a pointer to the last table.
+*/
+SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
+  struct SrcList_item *pItem = pSrc->a;
+  Table *pTab;
+  assert( pItem && pSrc->nSrc==1 );
+  pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+  sqlite3DeleteTable(pItem->pTab);
+  pItem->pTab = pTab;
+  if( pTab ){
+    pTab->nRef++;
+  }
+  if( sqlite3IndexedByLookup(pParse, pItem) ){
+    pTab = 0;
+  }
+  return pTab;
+}
+
+/*
+** Check to make sure the given table is writable.  If it is not
+** writable, generate an error message and return 1.  If it is
+** writable return 0;
+*/
+SQLITE_PRIVATE int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
+  /* A table is not writable under the following circumstances:
+  **
+  **   1) It is a virtual table and no implementation of the xUpdate method
+  **      has been provided, or
+  **   2) It is a system table (i.e. sqlite_master), this call is not
+  **      part of a nested parse and writable_schema pragma has not 
+  **      been specified.
+  **
+  ** In either case leave an error message in pParse and return non-zero.
+  */
+  if( ( IsVirtual(pTab) 
+     && sqlite3GetVTable(pParse->db, pTab)->pMod->pModule->xUpdate==0 )
+   || ( (pTab->tabFlags & TF_Readonly)!=0
+     && (pParse->db->flags & SQLITE_WriteSchema)==0
+     && pParse->nested==0 )
+  ){
+    sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
+    return 1;
+  }
+
+#ifndef SQLITE_OMIT_VIEW
+  if( !viewOk && pTab->pSelect ){
+    sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
+    return 1;
+  }
+#endif
+  return 0;
+}
+
+
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+/*
+** Evaluate a view and store its result in an ephemeral table.  The
+** pWhere argument is an optional WHERE clause that restricts the
+** set of rows in the view that are to be added to the ephemeral table.
+*/
+SQLITE_PRIVATE void sqlite3MaterializeView(
+  Parse *pParse,       /* Parsing context */
+  Table *pView,        /* View definition */
+  Expr *pWhere,        /* Optional WHERE clause to be added */
+  int iCur             /* Cursor number for ephemerial table */
+){
+  SelectDest dest;
+  Select *pDup;
+  sqlite3 *db = pParse->db;
+
+  pDup = sqlite3SelectDup(db, pView->pSelect, 0);
+  if( pWhere ){
+    SrcList *pFrom;
+    
+    pWhere = sqlite3ExprDup(db, pWhere, 0);
+    pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
+    if( pFrom ){
+      assert( pFrom->nSrc==1 );
+      pFrom->a[0].zAlias = sqlite3DbStrDup(db, pView->zName);
+      pFrom->a[0].pSelect = pDup;
+      assert( pFrom->a[0].pOn==0 );
+      assert( pFrom->a[0].pUsing==0 );
+    }else{
+      sqlite3SelectDelete(db, pDup);
+    }
+    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+  }
+  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
+  sqlite3Select(pParse, pDup, &dest);
+  sqlite3SelectDelete(db, pDup);
+}
+#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
+
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+/*
+** Generate an expression tree to implement the WHERE, ORDER BY,
+** and LIMIT/OFFSET portion of DELETE and UPDATE statements.
+**
+**     DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;
+**                            \__________________________/
+**                               pLimitWhere (pInClause)
+*/
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(
+  Parse *pParse,               /* The parser context */
+  SrcList *pSrc,               /* the FROM clause -- which tables to scan */
+  Expr *pWhere,                /* The WHERE clause.  May be null */
+  ExprList *pOrderBy,          /* The ORDER BY clause.  May be null */
+  Expr *pLimit,                /* The LIMIT clause.  May be null */
+  Expr *pOffset,               /* The OFFSET clause.  May be null */
+  char *zStmtType              /* Either DELETE or UPDATE.  For error messages. */
+){
+  Expr *pWhereRowid = NULL;    /* WHERE rowid .. */
+  Expr *pInClause = NULL;      /* WHERE rowid IN ( select ) */
+  Expr *pSelectRowid = NULL;   /* SELECT rowid ... */
+  ExprList *pEList = NULL;     /* Expression list contaning only pSelectRowid */
+  SrcList *pSelectSrc = NULL;  /* SELECT rowid FROM x ... (dup of pSrc) */
+  Select *pSelect = NULL;      /* Complete SELECT tree */
+
+  /* Check that there isn't an ORDER BY without a LIMIT clause.
+  */
+  if( pOrderBy && (pLimit == 0) ) {
+    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
+    pParse->parseError = 1;
+    goto limit_where_cleanup_2;
+  }
+
+  /* We only need to generate a select expression if there
+  ** is a limit/offset term to enforce.
+  */
+  if( pLimit == 0 ) {
+    /* if pLimit is null, pOffset will always be null as well. */
+    assert( pOffset == 0 );
+    return pWhere;
+  }
+
+  /* Generate a select expression tree to enforce the limit/offset 
+  ** term for the DELETE or UPDATE statement.  For example:
+  **   DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
+  ** becomes:
+  **   DELETE FROM table_a WHERE rowid IN ( 
+  **     SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
+  **   );
+  */
+
+  pSelectRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
+  if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
+  pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid);
+  if( pEList == 0 ) goto limit_where_cleanup_2;
+
+  /* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
+  ** and the SELECT subtree. */
+  pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc, 0);
+  if( pSelectSrc == 0 ) {
+    sqlite3ExprListDelete(pParse->db, pEList);
+    goto limit_where_cleanup_2;
+  }
+
+  /* generate the SELECT expression tree. */
+  pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,
+                             pOrderBy,0,pLimit,pOffset);
+  if( pSelect == 0 ) return 0;
+
+  /* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
+  pWhereRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
+  if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
+  pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
+  if( pInClause == 0 ) goto limit_where_cleanup_1;
+
+  pInClause->x.pSelect = pSelect;
+  pInClause->flags |= EP_xIsSelect;
+  sqlite3ExprSetHeight(pParse, pInClause);
+  return pInClause;
+
+  /* something went wrong. clean up anything allocated. */
+limit_where_cleanup_1:
+  sqlite3SelectDelete(pParse->db, pSelect);
+  return 0;
+
+limit_where_cleanup_2:
+  sqlite3ExprDelete(pParse->db, pWhere);
+  sqlite3ExprListDelete(pParse->db, pOrderBy);
+  sqlite3ExprDelete(pParse->db, pLimit);
+  sqlite3ExprDelete(pParse->db, pOffset);
+  return 0;
+}
+#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
+
+/*
+** Generate code for a DELETE FROM statement.
+**
+**     DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
+**                 \________/       \________________/
+**                  pTabList              pWhere
+*/
+SQLITE_PRIVATE void sqlite3DeleteFrom(
+  Parse *pParse,         /* The parser context */
+  SrcList *pTabList,     /* The table from which we should delete things */
+  Expr *pWhere           /* The WHERE clause.  May be null */
+){
+  Vdbe *v;               /* The virtual database engine */
+  Table *pTab;           /* The table from which records will be deleted */
+  const char *zDb;       /* Name of database holding pTab */
+  int end, addr = 0;     /* A couple addresses of generated code */
+  int i;                 /* Loop counter */
+  WhereInfo *pWInfo;     /* Information about the WHERE clause */
+  Index *pIdx;           /* For looping over indices of the table */
+  int iCur;              /* VDBE Cursor number for pTab */
+  sqlite3 *db;           /* Main database structure */
+  AuthContext sContext;  /* Authorization context */
+  NameContext sNC;       /* Name context to resolve expressions in */
+  int iDb;               /* Database number */
+  int memCnt = -1;       /* Memory cell used for change counting */
+  int rcauth;            /* Value returned by authorization callback */
+
+#ifndef SQLITE_OMIT_TRIGGER
+  int isView;                  /* True if attempting to delete from a view */
+  Trigger *pTrigger;           /* List of table triggers, if required */
+#endif
+
+  memset(&sContext, 0, sizeof(sContext));
+  db = pParse->db;
+  if( pParse->nErr || db->mallocFailed ){
+    goto delete_from_cleanup;
+  }
+  assert( pTabList->nSrc==1 );
+
+  /* Locate the table which we want to delete.  This table has to be
+  ** put in an SrcList structure because some of the subroutines we
+  ** will be calling are designed to work with multiple tables and expect
+  ** an SrcList* parameter instead of just a Table* parameter.
+  */
+  pTab = sqlite3SrcListLookup(pParse, pTabList);
+  if( pTab==0 )  goto delete_from_cleanup;
+
+  /* Figure out if we have any triggers and if the table being
+  ** deleted from is a view
+  */
+#ifndef SQLITE_OMIT_TRIGGER
+  pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
+  isView = pTab->pSelect!=0;
+#else
+# define pTrigger 0
+# define isView 0
+#endif
+#ifdef SQLITE_OMIT_VIEW
+# undef isView
+# define isView 0
+#endif
+
+  /* If pTab is really a view, make sure it has been initialized.
+  */
+  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
+    goto delete_from_cleanup;
+  }
+
+  if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
+    goto delete_from_cleanup;
+  }
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  assert( iDb<db->nDb );
+  zDb = db->aDb[iDb].zName;
+  rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
+  assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
+  if( rcauth==SQLITE_DENY ){
+    goto delete_from_cleanup;
+  }
+  assert(!isView || pTrigger);
+
+  /* Assign  cursor number to the table and all its indices.
+  */
+  assert( pTabList->nSrc==1 );
+  iCur = pTabList->a[0].iCursor = pParse->nTab++;
+  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+    pParse->nTab++;
+  }
+
+  /* Start the view context
+  */
+  if( isView ){
+    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
+  }
+
+  /* Begin generating code.
+  */
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ){
+    goto delete_from_cleanup;
+  }
+  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
+  sqlite3BeginWriteOperation(pParse, 1, iDb);
+
+  /* If we are trying to delete from a view, realize that view into
+  ** a ephemeral table.
+  */
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+  if( isView ){
+    sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
+  }
+#endif
+
+  /* Resolve the column names in the WHERE clause.
+  */
+  memset(&sNC, 0, sizeof(sNC));
+  sNC.pParse = pParse;
+  sNC.pSrcList = pTabList;
+  if( sqlite3ResolveExprNames(&sNC, pWhere) ){
+    goto delete_from_cleanup;
+  }
+
+  /* Initialize the counter of the number of rows deleted, if
+  ** we are counting rows.
+  */
+  if( db->flags & SQLITE_CountRows ){
+    memCnt = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
+  }
+
+#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
+  /* Special case: A DELETE without a WHERE clause deletes everything.
+  ** It is easier just to erase the whole table. Prior to version 3.6.5,
+  ** this optimization caused the row change count (the value returned by 
+  ** API function sqlite3_count_changes) to be set incorrectly.  */
+  if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab) 
+   && 0==sqlite3FkRequired(pParse, pTab, 0, 0)
+  ){
+    assert( !isView );
+    sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
+                      pTab->zName, P4_STATIC);
+    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+      assert( pIdx->pSchema==pTab->pSchema );
+      sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
+    }
+  }else
+#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
+  /* The usual case: There is a WHERE clause so we have to scan through
+  ** the table and pick which records to delete.
+  */
+  {
+    int iRowSet = ++pParse->nMem;   /* Register for rowset of rows to delete */
+    int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
+    int regRowid;                   /* Actual register containing rowids */
+
+    /* Collect rowids of every row to be deleted.
+    */
+    sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0,WHERE_DUPLICATES_OK);
+    if( pWInfo==0 ) goto delete_from_cleanup;
+    regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
+    sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
+    if( db->flags & SQLITE_CountRows ){
+      sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
+    }
+    sqlite3WhereEnd(pWInfo);
+
+    /* Delete every item whose key was written to the list during the
+    ** database scan.  We have to delete items after the scan is complete
+    ** because deleting an item can change the scan order.  */
+    end = sqlite3VdbeMakeLabel(v);
+
+    /* Unless this is a view, open cursors for the table we are 
+    ** deleting from and all its indices. If this is a view, then the
+    ** only effect this statement has is to fire the INSTEAD OF 
+    ** triggers.  */
+    if( !isView ){
+      sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
+    }
+
+    addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
+
+    /* Delete the row */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( IsVirtual(pTab) ){
+      const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
+      sqlite3VtabMakeWritable(pParse, pTab);
+      sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
+      sqlite3MayAbort(pParse);
+    }else
+#endif
+    {
+      int count = (pParse->nested==0);    /* True to count changes */
+      sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
+    }
+
+    /* End of the delete loop */
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
+    sqlite3VdbeResolveLabel(v, end);
+
+    /* Close the cursors open on the table and its indexes. */
+    if( !isView && !IsVirtual(pTab) ){
+      for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
+        sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
+      }
+      sqlite3VdbeAddOp1(v, OP_Close, iCur);
+    }
+  }
+
+  /* Update the sqlite_sequence table by storing the content of the
+  ** maximum rowid counter values recorded while inserting into
+  ** autoincrement tables.
+  */
+  if( pParse->nested==0 && pParse->pTriggerTab==0 ){
+    sqlite3AutoincrementEnd(pParse);
+  }
+
+  /* Return the number of rows that were deleted. If this routine is 
+  ** generating code because of a call to sqlite3NestedParse(), do not
+  ** invoke the callback function.
+  */
+  if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
+    sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
+  }
+
+delete_from_cleanup:
+  sqlite3AuthContextPop(&sContext);
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprDelete(db, pWhere);
+  return;
+}
+/* Make sure "isView" and other macros defined above are undefined. Otherwise
+** thely may interfere with compilation of other functions in this file
+** (or in another file, if this file becomes part of the amalgamation).  */
+#ifdef isView
+ #undef isView
+#endif
+#ifdef pTrigger
+ #undef pTrigger
+#endif
+
+/*
+** This routine generates VDBE code that causes a single row of a
+** single table to be deleted.
+**
+** The VDBE must be in a particular state when this routine is called.
+** These are the requirements:
+**
+**   1.  A read/write cursor pointing to pTab, the table containing the row
+**       to be deleted, must be opened as cursor number $iCur.
+**
+**   2.  Read/write cursors for all indices of pTab must be open as
+**       cursor number base+i for the i-th index.
+**
+**   3.  The record number of the row to be deleted must be stored in
+**       memory cell iRowid.
+**
+** This routine generates code to remove both the table record and all 
+** index entries that point to that record.
+*/
+SQLITE_PRIVATE void sqlite3GenerateRowDelete(
+  Parse *pParse,     /* Parsing context */
+  Table *pTab,       /* Table containing the row to be deleted */
+  int iCur,          /* Cursor number for the table */
+  int iRowid,        /* Memory cell that contains the rowid to delete */
+  int count,         /* If non-zero, increment the row change counter */
+  Trigger *pTrigger, /* List of triggers to (potentially) fire */
+  int onconf         /* Default ON CONFLICT policy for triggers */
+){
+  Vdbe *v = pParse->pVdbe;        /* Vdbe */
+  int iOld = 0;                   /* First register in OLD.* array */
+  int iLabel;                     /* Label resolved to end of generated code */
+
+  /* Vdbe is guaranteed to have been allocated by this stage. */
+  assert( v );
+
+  /* Seek cursor iCur to the row to delete. If this row no longer exists 
+  ** (this can happen if a trigger program has already deleted it), do
+  ** not attempt to delete it or fire any DELETE triggers.  */
+  iLabel = sqlite3VdbeMakeLabel(v);
+  sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
+ 
+  /* If there are any triggers to fire, allocate a range of registers to
+  ** use for the old.* references in the triggers.  */
+  if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){
+    u32 mask;                     /* Mask of OLD.* columns in use */
+    int iCol;                     /* Iterator used while populating OLD.* */
+
+    /* TODO: Could use temporary registers here. Also could attempt to
+    ** avoid copying the contents of the rowid register.  */
+    mask = sqlite3TriggerOldmask(pParse, pTrigger, 0, pTab, onconf);
+    mask |= sqlite3FkOldmask(pParse, pTab);
+    iOld = pParse->nMem+1;
+    pParse->nMem += (1 + pTab->nCol);
+
+    /* Populate the OLD.* pseudo-table register array. These values will be 
+    ** used by any BEFORE and AFTER triggers that exist.  */
+    sqlite3VdbeAddOp2(v, OP_Copy, iRowid, iOld);
+    for(iCol=0; iCol<pTab->nCol; iCol++){
+      if( mask==0xffffffff || mask&(1<<iCol) ){
+        int iTarget = iOld + iCol + 1;
+        sqlite3VdbeAddOp3(v, OP_Column, iCur, iCol, iTarget);
+        sqlite3ColumnDefault(v, pTab, iCol, iTarget);
+      }
+    }
+
+    /* Invoke BEFORE DELETE trigger programs. */
+    sqlite3CodeRowTrigger(pParse, pTrigger, 
+        TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
+    );
+
+    /* Seek the cursor to the row to be deleted again. It may be that
+    ** the BEFORE triggers coded above have already removed the row
+    ** being deleted. Do not attempt to delete the row a second time, and 
+    ** do not fire AFTER triggers.  */
+    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
+
+    /* Do FK processing. This call checks that any FK constraints that
+    ** refer to this table (i.e. constraints attached to other tables) 
+    ** are not violated by deleting this row.  */
+    sqlite3FkCheck(pParse, pTab, iOld, 0);
+  }
+
+  /* Delete the index and table entries. Skip this step if pTab is really
+  ** a view (in which case the only effect of the DELETE statement is to
+  ** fire the INSTEAD OF triggers).  */ 
+  if( pTab->pSelect==0 ){
+    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
+    sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
+    if( count ){
+      sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
+    }
+  }
+
+  /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
+  ** handle rows (possibly in other tables) that refer via a foreign key
+  ** to the row just deleted. */ 
+  sqlite3FkActions(pParse, pTab, 0, iOld);
+
+  /* Invoke AFTER DELETE trigger programs. */
+  sqlite3CodeRowTrigger(pParse, pTrigger, 
+      TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel
+  );
+
+  /* Jump here if the row had already been deleted before any BEFORE
+  ** trigger programs were invoked. Or if a trigger program throws a 
+  ** RAISE(IGNORE) exception.  */
+  sqlite3VdbeResolveLabel(v, iLabel);
+}
+
+/*
+** This routine generates VDBE code that causes the deletion of all
+** index entries associated with a single row of a single table.
+**
+** The VDBE must be in a particular state when this routine is called.
+** These are the requirements:
+**
+**   1.  A read/write cursor pointing to pTab, the table containing the row
+**       to be deleted, must be opened as cursor number "iCur".
+**
+**   2.  Read/write cursors for all indices of pTab must be open as
+**       cursor number iCur+i for the i-th index.
+**
+**   3.  The "iCur" cursor must be pointing to the row that is to be
+**       deleted.
+*/
+SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
+  Parse *pParse,     /* Parsing and code generating context */
+  Table *pTab,       /* Table containing the row to be deleted */
+  int iCur,          /* Cursor number for the table */
+  int *aRegIdx       /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
+){
+  int i;
+  Index *pIdx;
+  int r1;
+
+  for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
+    if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
+    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
+    sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
+  }
+}
+
+/*
+** Generate code that will assemble an index key and put it in register
+** regOut.  The key with be for index pIdx which is an index on pTab.
+** iCur is the index of a cursor open on the pTab table and pointing to
+** the entry that needs indexing.
+**
+** Return a register number which is the first in a block of
+** registers that holds the elements of the index key.  The
+** block of registers has already been deallocated by the time
+** this routine returns.
+*/
+SQLITE_PRIVATE int sqlite3GenerateIndexKey(
+  Parse *pParse,     /* Parsing context */
+  Index *pIdx,       /* The index for which to generate a key */
+  int iCur,          /* Cursor number for the pIdx->pTable table */
+  int regOut,        /* Write the new index key to this register */
+  int doMakeRec      /* Run the OP_MakeRecord instruction if true */
+){
+  Vdbe *v = pParse->pVdbe;
+  int j;
+  Table *pTab = pIdx->pTable;
+  int regBase;
+  int nCol;
+
+  nCol = pIdx->nColumn;
+  regBase = sqlite3GetTempRange(pParse, nCol+1);
+  sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
+  for(j=0; j<nCol; j++){
+    int idx = pIdx->aiColumn[j];
+    if( idx==pTab->iPKey ){
+      sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
+    }else{
+      sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
+      sqlite3ColumnDefault(v, pTab, idx, -1);
+    }
+  }
+  if( doMakeRec ){
+    sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
+    sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v, pIdx), 0);
+    sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
+  }
+  sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
+  return regBase;
+}
+
+
+/************** End of delete.c **********************************************/
+/************** Begin file func.c ********************************************/
+/*
+** 2002 February 23
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement various SQL
+** functions of SQLite.  
+**
+** There is only one exported symbol in this file - the function
+** sqliteRegisterBuildinFunctions() found at the bottom of the file.
+** All other code has file scope.
+*/
+
+/*
+** Return the collating function associated with a function.
+*/
+static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
+  return context->pColl;
+}
+
+/*
+** Implementation of the non-aggregate min() and max() functions
+*/
+static void minmaxFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int i;
+  int mask;    /* 0 for min() or 0xffffffff for max() */
+  int iBest;
+  CollSeq *pColl;
+
+  assert( argc>1 );
+  mask = sqlite3_user_data(context)==0 ? 0 : -1;
+  pColl = sqlite3GetFuncCollSeq(context);
+  assert( pColl );
+  assert( mask==-1 || mask==0 );
+  iBest = 0;
+  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
+  for(i=1; i<argc; i++){
+    if( sqlite3_value_type(argv[i])==SQLITE_NULL ) return;
+    if( (sqlite3MemCompare(argv[iBest], argv[i], pColl)^mask)>=0 ){
+      testcase( mask==0 );
+      iBest = i;
+    }
+  }
+  sqlite3_result_value(context, argv[iBest]);
+}
+
+/*
+** Return the type of the argument.
+*/
+static void typeofFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **argv
+){
+  const char *z = 0;
+  UNUSED_PARAMETER(NotUsed);
+  switch( sqlite3_value_type(argv[0]) ){
+    case SQLITE_INTEGER: z = "integer"; break;
+    case SQLITE_TEXT:    z = "text";    break;
+    case SQLITE_FLOAT:   z = "real";    break;
+    case SQLITE_BLOB:    z = "blob";    break;
+    default:             z = "null";    break;
+  }
+  sqlite3_result_text(context, z, -1, SQLITE_STATIC);
+}
+
+
+/*
+** Implementation of the length() function
+*/
+static void lengthFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int len;
+
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  switch( sqlite3_value_type(argv[0]) ){
+    case SQLITE_BLOB:
+    case SQLITE_INTEGER:
+    case SQLITE_FLOAT: {
+      sqlite3_result_int(context, sqlite3_value_bytes(argv[0]));
+      break;
+    }
+    case SQLITE_TEXT: {
+      const unsigned char *z = sqlite3_value_text(argv[0]);
+      if( z==0 ) return;
+      len = 0;
+      while( *z ){
+        len++;
+        SQLITE_SKIP_UTF8(z);
+      }
+      sqlite3_result_int(context, len);
+      break;
+    }
+    default: {
+      sqlite3_result_null(context);
+      break;
+    }
+  }
+}
+
+/*
+** Implementation of the abs() function
+*/
+static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  switch( sqlite3_value_type(argv[0]) ){
+    case SQLITE_INTEGER: {
+      i64 iVal = sqlite3_value_int64(argv[0]);
+      if( iVal<0 ){
+        if( (iVal<<1)==0 ){
+          sqlite3_result_error(context, "integer overflow", -1);
+          return;
+        }
+        iVal = -iVal;
+      } 
+      sqlite3_result_int64(context, iVal);
+      break;
+    }
+    case SQLITE_NULL: {
+      sqlite3_result_null(context);
+      break;
+    }
+    default: {
+      double rVal = sqlite3_value_double(argv[0]);
+      if( rVal<0 ) rVal = -rVal;
+      sqlite3_result_double(context, rVal);
+      break;
+    }
+  }
+}
+
+/*
+** Implementation of the substr() function.
+**
+** substr(x,p1,p2)  returns p2 characters of x[] beginning with p1.
+** p1 is 1-indexed.  So substr(x,1,1) returns the first character
+** of x.  If x is text, then we actually count UTF-8 characters.
+** If x is a blob, then we count bytes.
+**
+** If p1 is negative, then we begin abs(p1) from the end of x[].
+*/
+static void substrFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const unsigned char *z;
+  const unsigned char *z2;
+  int len;
+  int p0type;
+  i64 p1, p2;
+  int negP2 = 0;
+
+  assert( argc==3 || argc==2 );
+  if( sqlite3_value_type(argv[1])==SQLITE_NULL
+   || (argc==3 && sqlite3_value_type(argv[2])==SQLITE_NULL)
+  ){
+    return;
+  }
+  p0type = sqlite3_value_type(argv[0]);
+  if( p0type==SQLITE_BLOB ){
+    len = sqlite3_value_bytes(argv[0]);
+    z = sqlite3_value_blob(argv[0]);
+    if( z==0 ) return;
+    assert( len==sqlite3_value_bytes(argv[0]) );
+  }else{
+    z = sqlite3_value_text(argv[0]);
+    if( z==0 ) return;
+    len = 0;
+    for(z2=z; *z2; len++){
+      SQLITE_SKIP_UTF8(z2);
+    }
+  }
+  p1 = sqlite3_value_int(argv[1]);
+  if( argc==3 ){
+    p2 = sqlite3_value_int(argv[2]);
+    if( p2<0 ){
+      p2 = -p2;
+      negP2 = 1;
+    }
+  }else{
+    p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH];
+  }
+  if( p1<0 ){
+    p1 += len;
+    if( p1<0 ){
+      p2 += p1;
+      if( p2<0 ) p2 = 0;
+      p1 = 0;
+    }
+  }else if( p1>0 ){
+    p1--;
+  }else if( p2>0 ){
+    p2--;
+  }
+  if( negP2 ){
+    p1 -= p2;
+    if( p1<0 ){
+      p2 += p1;
+      p1 = 0;
+    }
+  }
+  assert( p1>=0 && p2>=0 );
+  if( p1+p2>len ){
+    p2 = len-p1;
+    if( p2<0 ) p2 = 0;
+  }
+  if( p0type!=SQLITE_BLOB ){
+    while( *z && p1 ){
+      SQLITE_SKIP_UTF8(z);
+      p1--;
+    }
+    for(z2=z; *z2 && p2; p2--){
+      SQLITE_SKIP_UTF8(z2);
+    }
+    sqlite3_result_text(context, (char*)z, (int)(z2-z), SQLITE_TRANSIENT);
+  }else{
+    sqlite3_result_blob(context, (char*)&z[p1], (int)p2, SQLITE_TRANSIENT);
+  }
+}
+
+/*
+** Implementation of the round() function
+*/
+#ifndef SQLITE_OMIT_FLOATING_POINT
+static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  int n = 0;
+  double r;
+  char *zBuf;
+  assert( argc==1 || argc==2 );
+  if( argc==2 ){
+    if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return;
+    n = sqlite3_value_int(argv[1]);
+    if( n>30 ) n = 30;
+    if( n<0 ) n = 0;
+  }
+  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
+  r = sqlite3_value_double(argv[0]);
+  zBuf = sqlite3_mprintf("%.*f",n,r);
+  if( zBuf==0 ){
+    sqlite3_result_error_nomem(context);
+  }else{
+    sqlite3AtoF(zBuf, &r);
+    sqlite3_free(zBuf);
+    sqlite3_result_double(context, r);
+  }
+}
+#endif
+
+/*
+** Allocate nByte bytes of space using sqlite3_malloc(). If the
+** allocation fails, call sqlite3_result_error_nomem() to notify
+** the database handle that malloc() has failed and return NULL.
+** If nByte is larger than the maximum string or blob length, then
+** raise an SQLITE_TOOBIG exception and return NULL.
+*/
+static void *contextMalloc(sqlite3_context *context, i64 nByte){
+  char *z;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  assert( nByte>0 );
+  testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH] );
+  testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
+  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    sqlite3_result_error_toobig(context);
+    z = 0;
+  }else{
+    z = sqlite3Malloc((int)nByte);
+    if( !z ){
+      sqlite3_result_error_nomem(context);
+    }
+  }
+  return z;
+}
+
+/*
+** Implementation of the upper() and lower() SQL functions.
+*/
+static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  char *z1;
+  const char *z2;
+  int i, n;
+  UNUSED_PARAMETER(argc);
+  z2 = (char*)sqlite3_value_text(argv[0]);
+  n = sqlite3_value_bytes(argv[0]);
+  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
+  assert( z2==(char*)sqlite3_value_text(argv[0]) );
+  if( z2 ){
+    z1 = contextMalloc(context, ((i64)n)+1);
+    if( z1 ){
+      memcpy(z1, z2, n+1);
+      for(i=0; z1[i]; i++){
+        z1[i] = (char)sqlite3Toupper(z1[i]);
+      }
+      sqlite3_result_text(context, z1, -1, sqlite3_free);
+    }
+  }
+}
+static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  u8 *z1;
+  const char *z2;
+  int i, n;
+  UNUSED_PARAMETER(argc);
+  z2 = (char*)sqlite3_value_text(argv[0]);
+  n = sqlite3_value_bytes(argv[0]);
+  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
+  assert( z2==(char*)sqlite3_value_text(argv[0]) );
+  if( z2 ){
+    z1 = contextMalloc(context, ((i64)n)+1);
+    if( z1 ){
+      memcpy(z1, z2, n+1);
+      for(i=0; z1[i]; i++){
+        z1[i] = sqlite3Tolower(z1[i]);
+      }
+      sqlite3_result_text(context, (char *)z1, -1, sqlite3_free);
+    }
+  }
+}
+
+/*
+** Implementation of the IFNULL(), NVL(), and COALESCE() functions.  
+** All three do the same thing.  They return the first non-NULL
+** argument.
+*/
+static void ifnullFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int i;
+  for(i=0; i<argc; i++){
+    if( SQLITE_NULL!=sqlite3_value_type(argv[i]) ){
+      sqlite3_result_value(context, argv[i]);
+      break;
+    }
+  }
+}
+
+/*
+** Implementation of random().  Return a random integer.  
+*/
+static void randomFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **NotUsed2
+){
+  sqlite_int64 r;
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_randomness(sizeof(r), &r);
+  if( r<0 ){
+    /* We need to prevent a random number of 0x8000000000000000 
+    ** (or -9223372036854775808) since when you do abs() of that
+    ** number of you get the same value back again.  To do this
+    ** in a way that is testable, mask the sign bit off of negative
+    ** values, resulting in a positive value.  Then take the 
+    ** 2s complement of that positive value.  The end result can
+    ** therefore be no less than -9223372036854775807.
+    */
+    r = -(r ^ (((sqlite3_int64)1)<<63));
+  }
+  sqlite3_result_int64(context, r);
+}
+
+/*
+** Implementation of randomblob(N).  Return a random blob
+** that is N bytes long.
+*/
+static void randomBlob(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int n;
+  unsigned char *p;
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  n = sqlite3_value_int(argv[0]);
+  if( n<1 ){
+    n = 1;
+  }
+  p = contextMalloc(context, n);
+  if( p ){
+    sqlite3_randomness(n, p);
+    sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
+  }
+}
+
+/*
+** Implementation of the last_insert_rowid() SQL function.  The return
+** value is the same as the sqlite3_last_insert_rowid() API function.
+*/
+static void last_insert_rowid(
+  sqlite3_context *context, 
+  int NotUsed, 
+  sqlite3_value **NotUsed2
+){
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_result_int64(context, sqlite3_last_insert_rowid(db));
+}
+
+/*
+** Implementation of the changes() SQL function.  The return value is the
+** same as the sqlite3_changes() API function.
+*/
+static void changes(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **NotUsed2
+){
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_result_int(context, sqlite3_changes(db));
+}
+
+/*
+** Implementation of the total_changes() SQL function.  The return value is
+** the same as the sqlite3_total_changes() API function.
+*/
+static void total_changes(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **NotUsed2
+){
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_result_int(context, sqlite3_total_changes(db));
+}
+
+/*
+** A structure defining how to do GLOB-style comparisons.
+*/
+struct compareInfo {
+  u8 matchAll;
+  u8 matchOne;
+  u8 matchSet;
+  u8 noCase;
+};
+
+/*
+** For LIKE and GLOB matching on EBCDIC machines, assume that every
+** character is exactly one byte in size.  Also, all characters are
+** able to participate in upper-case-to-lower-case mappings in EBCDIC
+** whereas only characters less than 0x80 do in ASCII.
+*/
+#if defined(SQLITE_EBCDIC)
+# define sqlite3Utf8Read(A,C)    (*(A++))
+# define GlogUpperToLower(A)     A = sqlite3UpperToLower[A]
+#else
+# define GlogUpperToLower(A)     if( A<0x80 ){ A = sqlite3UpperToLower[A]; }
+#endif
+
+static const struct compareInfo globInfo = { '*', '?', '[', 0 };
+/* The correct SQL-92 behavior is for the LIKE operator to ignore
+** case.  Thus  'a' LIKE 'A' would be true. */
+static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
+/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
+** is case sensitive causing 'a' LIKE 'A' to be false */
+static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };
+
+/*
+** Compare two UTF-8 strings for equality where the first string can
+** potentially be a "glob" expression.  Return true (1) if they
+** are the same and false (0) if they are different.
+**
+** Globbing rules:
+**
+**      '*'       Matches any sequence of zero or more characters.
+**
+**      '?'       Matches exactly one character.
+**
+**     [...]      Matches one character from the enclosed list of
+**                characters.
+**
+**     [^...]     Matches one character not in the enclosed list.
+**
+** With the [...] and [^...] matching, a ']' character can be included
+** in the list by making it the first character after '[' or '^'.  A
+** range of characters can be specified using '-'.  Example:
+** "[a-z]" matches any single lower-case letter.  To match a '-', make
+** it the last character in the list.
+**
+** This routine is usually quick, but can be N**2 in the worst case.
+**
+** Hints: to match '*' or '?', put them in "[]".  Like this:
+**
+**         abc[*]xyz        Matches "abc*xyz" only
+*/
+static int patternCompare(
+  const u8 *zPattern,              /* The glob pattern */
+  const u8 *zString,               /* The string to compare against the glob */
+  const struct compareInfo *pInfo, /* Information about how to do the compare */
+  const int esc                    /* The escape character */
+){
+  int c, c2;
+  int invert;
+  int seen;
+  u8 matchOne = pInfo->matchOne;
+  u8 matchAll = pInfo->matchAll;
+  u8 matchSet = pInfo->matchSet;
+  u8 noCase = pInfo->noCase; 
+  int prevEscape = 0;     /* True if the previous character was 'escape' */
+
+  while( (c = sqlite3Utf8Read(zPattern,&zPattern))!=0 ){
+    if( !prevEscape && c==matchAll ){
+      while( (c=sqlite3Utf8Read(zPattern,&zPattern)) == matchAll
+               || c == matchOne ){
+        if( c==matchOne && sqlite3Utf8Read(zString, &zString)==0 ){
+          return 0;
+        }
+      }
+      if( c==0 ){
+        return 1;
+      }else if( c==esc ){
+        c = sqlite3Utf8Read(zPattern, &zPattern);
+        if( c==0 ){
+          return 0;
+        }
+      }else if( c==matchSet ){
+        assert( esc==0 );         /* This is GLOB, not LIKE */
+        assert( matchSet<0x80 );  /* '[' is a single-byte character */
+        while( *zString && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
+          SQLITE_SKIP_UTF8(zString);
+        }
+        return *zString!=0;
+      }
+      while( (c2 = sqlite3Utf8Read(zString,&zString))!=0 ){
+        if( noCase ){
+          GlogUpperToLower(c2);
+          GlogUpperToLower(c);
+          while( c2 != 0 && c2 != c ){
+            c2 = sqlite3Utf8Read(zString, &zString);
+            GlogUpperToLower(c2);
+          }
+        }else{
+          while( c2 != 0 && c2 != c ){
+            c2 = sqlite3Utf8Read(zString, &zString);
+          }
+        }
+        if( c2==0 ) return 0;
+        if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
+      }
+      return 0;
+    }else if( !prevEscape && c==matchOne ){
+      if( sqlite3Utf8Read(zString, &zString)==0 ){
+        return 0;
+      }
+    }else if( c==matchSet ){
+      int prior_c = 0;
+      assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
+      seen = 0;
+      invert = 0;
+      c = sqlite3Utf8Read(zString, &zString);
+      if( c==0 ) return 0;
+      c2 = sqlite3Utf8Read(zPattern, &zPattern);
+      if( c2=='^' ){
+        invert = 1;
+        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+      }
+      if( c2==']' ){
+        if( c==']' ) seen = 1;
+        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+      }
+      while( c2 && c2!=']' ){
+        if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
+          c2 = sqlite3Utf8Read(zPattern, &zPattern);
+          if( c>=prior_c && c<=c2 ) seen = 1;
+          prior_c = 0;
+        }else{
+          if( c==c2 ){
+            seen = 1;
+          }
+          prior_c = c2;
+        }
+        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+      }
+      if( c2==0 || (seen ^ invert)==0 ){
+        return 0;
+      }
+    }else if( esc==c && !prevEscape ){
+      prevEscape = 1;
+    }else{
+      c2 = sqlite3Utf8Read(zString, &zString);
+      if( noCase ){
+        GlogUpperToLower(c);
+        GlogUpperToLower(c2);
+      }
+      if( c!=c2 ){
+        return 0;
+      }
+      prevEscape = 0;
+    }
+  }
+  return *zString==0;
+}
+
+/*
+** Count the number of times that the LIKE operator (or GLOB which is
+** just a variation of LIKE) gets called.  This is used for testing
+** only.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_like_count = 0;
+#endif
+
+
+/*
+** Implementation of the like() SQL function.  This function implements
+** the build-in LIKE operator.  The first argument to the function is the
+** pattern and the second argument is the string.  So, the SQL statements:
+**
+**       A LIKE B
+**
+** is implemented as like(B,A).
+**
+** This same function (with a different compareInfo structure) computes
+** the GLOB operator.
+*/
+static void likeFunc(
+  sqlite3_context *context, 
+  int argc, 
+  sqlite3_value **argv
+){
+  const unsigned char *zA, *zB;
+  int escape = 0;
+  int nPat;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+
+  zB = sqlite3_value_text(argv[0]);
+  zA = sqlite3_value_text(argv[1]);
+
+  /* Limit the length of the LIKE or GLOB pattern to avoid problems
+  ** of deep recursion and N*N behavior in patternCompare().
+  */
+  nPat = sqlite3_value_bytes(argv[0]);
+  testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] );
+  testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]+1 );
+  if( nPat > db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){
+    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
+    return;
+  }
+  assert( zB==sqlite3_value_text(argv[0]) );  /* Encoding did not change */
+
+  if( argc==3 ){
+    /* The escape character string must consist of a single UTF-8 character.
+    ** Otherwise, return an error.
+    */
+    const unsigned char *zEsc = sqlite3_value_text(argv[2]);
+    if( zEsc==0 ) return;
+    if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){
+      sqlite3_result_error(context, 
+          "ESCAPE expression must be a single character", -1);
+      return;
+    }
+    escape = sqlite3Utf8Read(zEsc, &zEsc);
+  }
+  if( zA && zB ){
+    struct compareInfo *pInfo = sqlite3_user_data(context);
+#ifdef SQLITE_TEST
+    sqlite3_like_count++;
+#endif
+    
+    sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape));
+  }
+}
+
+/*
+** Implementation of the NULLIF(x,y) function.  The result is the first
+** argument if the arguments are different.  The result is NULL if the
+** arguments are equal to each other.
+*/
+static void nullifFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **argv
+){
+  CollSeq *pColl = sqlite3GetFuncCollSeq(context);
+  UNUSED_PARAMETER(NotUsed);
+  if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){
+    sqlite3_result_value(context, argv[0]);
+  }
+}
+
+/*
+** Implementation of the sqlite_version() function.  The result is the version
+** of the SQLite library that is running.
+*/
+static void versionFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **NotUsed2
+){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_result_text(context, sqlite3_version, -1, SQLITE_STATIC);
+}
+
+/*
+** Implementation of the sqlite_source_id() function. The result is a string
+** that identifies the particular version of the source code used to build
+** SQLite.
+*/
+static void sourceidFunc(
+  sqlite3_context *context,
+  int NotUsed,
+  sqlite3_value **NotUsed2
+){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_result_text(context, SQLITE_SOURCE_ID, -1, SQLITE_STATIC);
+}
+
+/* Array for converting from half-bytes (nybbles) into ASCII hex
+** digits. */
+static const char hexdigits[] = {
+  '0', '1', '2', '3', '4', '5', '6', '7',
+  '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 
+};
+
+/*
+** EXPERIMENTAL - This is not an official function.  The interface may
+** change.  This function may disappear.  Do not write code that depends
+** on this function.
+**
+** Implementation of the QUOTE() function.  This function takes a single
+** argument.  If the argument is numeric, the return value is the same as
+** the argument.  If the argument is NULL, the return value is the string
+** "NULL".  Otherwise, the argument is enclosed in single quotes with
+** single-quote escapes.
+*/
+static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  switch( sqlite3_value_type(argv[0]) ){
+    case SQLITE_INTEGER:
+    case SQLITE_FLOAT: {
+      sqlite3_result_value(context, argv[0]);
+      break;
+    }
+    case SQLITE_BLOB: {
+      char *zText = 0;
+      char const *zBlob = sqlite3_value_blob(argv[0]);
+      int nBlob = sqlite3_value_bytes(argv[0]);
+      assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */
+      zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); 
+      if( zText ){
+        int i;
+        for(i=0; i<nBlob; i++){
+          zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F];
+          zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F];
+        }
+        zText[(nBlob*2)+2] = '\'';
+        zText[(nBlob*2)+3] = '\0';
+        zText[0] = 'X';
+        zText[1] = '\'';
+        sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT);
+        sqlite3_free(zText);
+      }
+      break;
+    }
+    case SQLITE_TEXT: {
+      int i,j;
+      u64 n;
+      const unsigned char *zArg = sqlite3_value_text(argv[0]);
+      char *z;
+
+      if( zArg==0 ) return;
+      for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; }
+      z = contextMalloc(context, ((i64)i)+((i64)n)+3);
+      if( z ){
+        z[0] = '\'';
+        for(i=0, j=1; zArg[i]; i++){
+          z[j++] = zArg[i];
+          if( zArg[i]=='\'' ){
+            z[j++] = '\'';
+          }
+        }
+        z[j++] = '\'';
+        z[j] = 0;
+        sqlite3_result_text(context, z, j, sqlite3_free);
+      }
+      break;
+    }
+    default: {
+      assert( sqlite3_value_type(argv[0])==SQLITE_NULL );
+      sqlite3_result_text(context, "NULL", 4, SQLITE_STATIC);
+      break;
+    }
+  }
+}
+
+/*
+** The hex() function.  Interpret the argument as a blob.  Return
+** a hexadecimal rendering as text.
+*/
+static void hexFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int i, n;
+  const unsigned char *pBlob;
+  char *zHex, *z;
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  pBlob = sqlite3_value_blob(argv[0]);
+  n = sqlite3_value_bytes(argv[0]);
+  assert( pBlob==sqlite3_value_blob(argv[0]) );  /* No encoding change */
+  z = zHex = contextMalloc(context, ((i64)n)*2 + 1);
+  if( zHex ){
+    for(i=0; i<n; i++, pBlob++){
+      unsigned char c = *pBlob;
+      *(z++) = hexdigits[(c>>4)&0xf];
+      *(z++) = hexdigits[c&0xf];
+    }
+    *z = 0;
+    sqlite3_result_text(context, zHex, n*2, sqlite3_free);
+  }
+}
+
+/*
+** The zeroblob(N) function returns a zero-filled blob of size N bytes.
+*/
+static void zeroblobFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  i64 n;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  n = sqlite3_value_int64(argv[0]);
+  testcase( n==db->aLimit[SQLITE_LIMIT_LENGTH] );
+  testcase( n==db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
+  if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    sqlite3_result_error_toobig(context);
+  }else{
+    sqlite3_result_zeroblob(context, (int)n);
+  }
+}
+
+/*
+** The replace() function.  Three arguments are all strings: call
+** them A, B, and C. The result is also a string which is derived
+** from A by replacing every occurance of B with C.  The match
+** must be exact.  Collating sequences are not used.
+*/
+static void replaceFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const unsigned char *zStr;        /* The input string A */
+  const unsigned char *zPattern;    /* The pattern string B */
+  const unsigned char *zRep;        /* The replacement string C */
+  unsigned char *zOut;              /* The output */
+  int nStr;                /* Size of zStr */
+  int nPattern;            /* Size of zPattern */
+  int nRep;                /* Size of zRep */
+  i64 nOut;                /* Maximum size of zOut */
+  int loopLimit;           /* Last zStr[] that might match zPattern[] */
+  int i, j;                /* Loop counters */
+
+  assert( argc==3 );
+  UNUSED_PARAMETER(argc);
+  zStr = sqlite3_value_text(argv[0]);
+  if( zStr==0 ) return;
+  nStr = sqlite3_value_bytes(argv[0]);
+  assert( zStr==sqlite3_value_text(argv[0]) );  /* No encoding change */
+  zPattern = sqlite3_value_text(argv[1]);
+  if( zPattern==0 ){
+    assert( sqlite3_value_type(argv[1])==SQLITE_NULL
+            || sqlite3_context_db_handle(context)->mallocFailed );
+    return;
+  }
+  if( zPattern[0]==0 ){
+    assert( sqlite3_value_type(argv[1])!=SQLITE_NULL );
+    sqlite3_result_value(context, argv[0]);
+    return;
+  }
+  nPattern = sqlite3_value_bytes(argv[1]);
+  assert( zPattern==sqlite3_value_text(argv[1]) );  /* No encoding change */
+  zRep = sqlite3_value_text(argv[2]);
+  if( zRep==0 ) return;
+  nRep = sqlite3_value_bytes(argv[2]);
+  assert( zRep==sqlite3_value_text(argv[2]) );
+  nOut = nStr + 1;
+  assert( nOut<SQLITE_MAX_LENGTH );
+  zOut = contextMalloc(context, (i64)nOut);
+  if( zOut==0 ){
+    return;
+  }
+  loopLimit = nStr - nPattern;  
+  for(i=j=0; i<=loopLimit; i++){
+    if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){
+      zOut[j++] = zStr[i];
+    }else{
+      u8 *zOld;
+      sqlite3 *db = sqlite3_context_db_handle(context);
+      nOut += nRep - nPattern;
+      testcase( nOut-1==db->aLimit[SQLITE_LIMIT_LENGTH] );
+      testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] );
+      if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+        sqlite3_result_error_toobig(context);
+        sqlite3DbFree(db, zOut);
+        return;
+      }
+      zOld = zOut;
+      zOut = sqlite3_realloc(zOut, (int)nOut);
+      if( zOut==0 ){
+        sqlite3_result_error_nomem(context);
+        sqlite3DbFree(db, zOld);
+        return;
+      }
+      memcpy(&zOut[j], zRep, nRep);
+      j += nRep;
+      i += nPattern-1;
+    }
+  }
+  assert( j+nStr-i+1==nOut );
+  memcpy(&zOut[j], &zStr[i], nStr-i);
+  j += nStr - i;
+  assert( j<=nOut );
+  zOut[j] = 0;
+  sqlite3_result_text(context, (char*)zOut, j, sqlite3_free);
+}
+
+/*
+** Implementation of the TRIM(), LTRIM(), and RTRIM() functions.
+** The userdata is 0x1 for left trim, 0x2 for right trim, 0x3 for both.
+*/
+static void trimFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const unsigned char *zIn;         /* Input string */
+  const unsigned char *zCharSet;    /* Set of characters to trim */
+  int nIn;                          /* Number of bytes in input */
+  int flags;                        /* 1: trimleft  2: trimright  3: trim */
+  int i;                            /* Loop counter */
+  unsigned char *aLen = 0;          /* Length of each character in zCharSet */
+  unsigned char **azChar = 0;       /* Individual characters in zCharSet */
+  int nChar;                        /* Number of characters in zCharSet */
+
+  if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
+    return;
+  }
+  zIn = sqlite3_value_text(argv[0]);
+  if( zIn==0 ) return;
+  nIn = sqlite3_value_bytes(argv[0]);
+  assert( zIn==sqlite3_value_text(argv[0]) );
+  if( argc==1 ){
+    static const unsigned char lenOne[] = { 1 };
+    static unsigned char * const azOne[] = { (u8*)" " };
+    nChar = 1;
+    aLen = (u8*)lenOne;
+    azChar = (unsigned char **)azOne;
+    zCharSet = 0;
+  }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){
+    return;
+  }else{
+    const unsigned char *z;
+    for(z=zCharSet, nChar=0; *z; nChar++){
+      SQLITE_SKIP_UTF8(z);
+    }
+    if( nChar>0 ){
+      azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1));
+      if( azChar==0 ){
+        return;
+      }
+      aLen = (unsigned char*)&azChar[nChar];
+      for(z=zCharSet, nChar=0; *z; nChar++){
+        azChar[nChar] = (unsigned char *)z;
+        SQLITE_SKIP_UTF8(z);
+        aLen[nChar] = (u8)(z - azChar[nChar]);
+      }
+    }
+  }
+  if( nChar>0 ){
+    flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context));
+    if( flags & 1 ){
+      while( nIn>0 ){
+        int len = 0;
+        for(i=0; i<nChar; i++){
+          len = aLen[i];
+          if( len<=nIn && memcmp(zIn, azChar[i], len)==0 ) break;
+        }
+        if( i>=nChar ) break;
+        zIn += len;
+        nIn -= len;
+      }
+    }
+    if( flags & 2 ){
+      while( nIn>0 ){
+        int len = 0;
+        for(i=0; i<nChar; i++){
+          len = aLen[i];
+          if( len<=nIn && memcmp(&zIn[nIn-len],azChar[i],len)==0 ) break;
+        }
+        if( i>=nChar ) break;
+        nIn -= len;
+      }
+    }
+    if( zCharSet ){
+      sqlite3_free(azChar);
+    }
+  }
+  sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
+}
+
+
+#ifdef SQLITE_SOUNDEX
+/*
+** Compute the soundex encoding of a word.
+*/
+static void soundexFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  char zResult[8];
+  const u8 *zIn;
+  int i, j;
+  static const unsigned char iCode[] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0,
+    1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0,
+    0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0,
+    1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0,
+  };
+  assert( argc==1 );
+  zIn = (u8*)sqlite3_value_text(argv[0]);
+  if( zIn==0 ) zIn = (u8*)"";
+  for(i=0; zIn[i] && !sqlite3Isalpha(zIn[i]); i++){}
+  if( zIn[i] ){
+    u8 prevcode = iCode[zIn[i]&0x7f];
+    zResult[0] = sqlite3Toupper(zIn[i]);
+    for(j=1; j<4 && zIn[i]; i++){
+      int code = iCode[zIn[i]&0x7f];
+      if( code>0 ){
+        if( code!=prevcode ){
+          prevcode = code;
+          zResult[j++] = code + '0';
+        }
+      }else{
+        prevcode = 0;
+      }
+    }
+    while( j<4 ){
+      zResult[j++] = '0';
+    }
+    zResult[j] = 0;
+    sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT);
+  }else{
+    sqlite3_result_text(context, "?000", 4, SQLITE_STATIC);
+  }
+}
+#endif
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** A function that loads a shared-library extension then returns NULL.
+*/
+static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){
+  const char *zFile = (const char *)sqlite3_value_text(argv[0]);
+  const char *zProc;
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  char *zErrMsg = 0;
+
+  if( argc==2 ){
+    zProc = (const char *)sqlite3_value_text(argv[1]);
+  }else{
+    zProc = 0;
+  }
+  if( zFile && sqlite3_load_extension(db, zFile, zProc, &zErrMsg) ){
+    sqlite3_result_error(context, zErrMsg, -1);
+    sqlite3_free(zErrMsg);
+  }
+}
+#endif
+
+
+/*
+** An instance of the following structure holds the context of a
+** sum() or avg() aggregate computation.
+*/
+typedef struct SumCtx SumCtx;
+struct SumCtx {
+  double rSum;      /* Floating point sum */
+  i64 iSum;         /* Integer sum */   
+  i64 cnt;          /* Number of elements summed */
+  u8 overflow;      /* True if integer overflow seen */
+  u8 approx;        /* True if non-integer value was input to the sum */
+};
+
+/*
+** Routines used to compute the sum, average, and total.
+**
+** The SUM() function follows the (broken) SQL standard which means
+** that it returns NULL if it sums over no inputs.  TOTAL returns
+** 0.0 in that case.  In addition, TOTAL always returns a float where
+** SUM might return an integer if it never encounters a floating point
+** value.  TOTAL never fails, but SUM might through an exception if
+** it overflows an integer.
+*/
+static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){
+  SumCtx *p;
+  int type;
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  p = sqlite3_aggregate_context(context, sizeof(*p));
+  type = sqlite3_value_numeric_type(argv[0]);
+  if( p && type!=SQLITE_NULL ){
+    p->cnt++;
+    if( type==SQLITE_INTEGER ){
+      i64 v = sqlite3_value_int64(argv[0]);
+      p->rSum += v;
+      if( (p->approx|p->overflow)==0 ){
+        i64 iNewSum = p->iSum + v;
+        int s1 = (int)(p->iSum >> (sizeof(i64)*8-1));
+        int s2 = (int)(v       >> (sizeof(i64)*8-1));
+        int s3 = (int)(iNewSum >> (sizeof(i64)*8-1));
+        p->overflow = ((s1&s2&~s3) | (~s1&~s2&s3))?1:0;
+        p->iSum = iNewSum;
+      }
+    }else{
+      p->rSum += sqlite3_value_double(argv[0]);
+      p->approx = 1;
+    }
+  }
+}
+static void sumFinalize(sqlite3_context *context){
+  SumCtx *p;
+  p = sqlite3_aggregate_context(context, 0);
+  if( p && p->cnt>0 ){
+    if( p->overflow ){
+      sqlite3_result_error(context,"integer overflow",-1);
+    }else if( p->approx ){
+      sqlite3_result_double(context, p->rSum);
+    }else{
+      sqlite3_result_int64(context, p->iSum);
+    }
+  }
+}
+static void avgFinalize(sqlite3_context *context){
+  SumCtx *p;
+  p = sqlite3_aggregate_context(context, 0);
+  if( p && p->cnt>0 ){
+    sqlite3_result_double(context, p->rSum/(double)p->cnt);
+  }
+}
+static void totalFinalize(sqlite3_context *context){
+  SumCtx *p;
+  p = sqlite3_aggregate_context(context, 0);
+  /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+  sqlite3_result_double(context, p ? p->rSum : (double)0);
+}
+
+/*
+** The following structure keeps track of state information for the
+** count() aggregate function.
+*/
+typedef struct CountCtx CountCtx;
+struct CountCtx {
+  i64 n;
+};
+
+/*
+** Routines to implement the count() aggregate function.
+*/
+static void countStep(sqlite3_context *context, int argc, sqlite3_value **argv){
+  CountCtx *p;
+  p = sqlite3_aggregate_context(context, sizeof(*p));
+  if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && p ){
+    p->n++;
+  }
+
+#ifndef SQLITE_OMIT_DEPRECATED
+  /* The sqlite3_aggregate_count() function is deprecated.  But just to make
+  ** sure it still operates correctly, verify that its count agrees with our 
+  ** internal count when using count(*) and when the total count can be
+  ** expressed as a 32-bit integer. */
+  assert( argc==1 || p==0 || p->n>0x7fffffff
+          || p->n==sqlite3_aggregate_count(context) );
+#endif
+}   
+static void countFinalize(sqlite3_context *context){
+  CountCtx *p;
+  p = sqlite3_aggregate_context(context, 0);
+  sqlite3_result_int64(context, p ? p->n : 0);
+}
+
+/*
+** Routines to implement min() and max() aggregate functions.
+*/
+static void minmaxStep(
+  sqlite3_context *context, 
+  int NotUsed, 
+  sqlite3_value **argv
+){
+  Mem *pArg  = (Mem *)argv[0];
+  Mem *pBest;
+  UNUSED_PARAMETER(NotUsed);
+
+  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
+  pBest = (Mem *)sqlite3_aggregate_context(context, sizeof(*pBest));
+  if( !pBest ) return;
+
+  if( pBest->flags ){
+    int max;
+    int cmp;
+    CollSeq *pColl = sqlite3GetFuncCollSeq(context);
+    /* This step function is used for both the min() and max() aggregates,
+    ** the only difference between the two being that the sense of the
+    ** comparison is inverted. For the max() aggregate, the
+    ** sqlite3_user_data() function returns (void *)-1. For min() it
+    ** returns (void *)db, where db is the sqlite3* database pointer.
+    ** Therefore the next statement sets variable 'max' to 1 for the max()
+    ** aggregate, or 0 for min().
+    */
+    max = sqlite3_user_data(context)!=0;
+    cmp = sqlite3MemCompare(pBest, pArg, pColl);
+    if( (max && cmp<0) || (!max && cmp>0) ){
+      sqlite3VdbeMemCopy(pBest, pArg);
+    }
+  }else{
+    sqlite3VdbeMemCopy(pBest, pArg);
+  }
+}
+static void minMaxFinalize(sqlite3_context *context){
+  sqlite3_value *pRes;
+  pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0);
+  if( pRes ){
+    if( ALWAYS(pRes->flags) ){
+      sqlite3_result_value(context, pRes);
+    }
+    sqlite3VdbeMemRelease(pRes);
+  }
+}
+
+/*
+** group_concat(EXPR, ?SEPARATOR?)
+*/
+static void groupConcatStep(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const char *zVal;
+  StrAccum *pAccum;
+  const char *zSep;
+  int nVal, nSep;
+  assert( argc==1 || argc==2 );
+  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
+  pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum));
+
+  if( pAccum ){
+    sqlite3 *db = sqlite3_context_db_handle(context);
+    int firstTerm = pAccum->useMalloc==0;
+    pAccum->useMalloc = 1;
+    pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
+    if( !firstTerm ){
+      if( argc==2 ){
+        zSep = (char*)sqlite3_value_text(argv[1]);
+        nSep = sqlite3_value_bytes(argv[1]);
+      }else{
+        zSep = ",";
+        nSep = 1;
+      }
+      sqlite3StrAccumAppend(pAccum, zSep, nSep);
+    }
+    zVal = (char*)sqlite3_value_text(argv[0]);
+    nVal = sqlite3_value_bytes(argv[0]);
+    sqlite3StrAccumAppend(pAccum, zVal, nVal);
+  }
+}
+static void groupConcatFinalize(sqlite3_context *context){
+  StrAccum *pAccum;
+  pAccum = sqlite3_aggregate_context(context, 0);
+  if( pAccum ){
+    if( pAccum->tooBig ){
+      sqlite3_result_error_toobig(context);
+    }else if( pAccum->mallocFailed ){
+      sqlite3_result_error_nomem(context);
+    }else{    
+      sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, 
+                          sqlite3_free);
+    }
+  }
+}
+
+/*
+** This function registered all of the above C functions as SQL
+** functions.  This should be the only routine in this file with
+** external linkage.
+*/
+SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
+#ifndef SQLITE_OMIT_ALTERTABLE
+  sqlite3AlterFunctions(db);
+#endif
+  if( !db->mallocFailed ){
+    int rc = sqlite3_overload_function(db, "MATCH", 2);
+    assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
+    if( rc==SQLITE_NOMEM ){
+      db->mallocFailed = 1;
+    }
+  }
+}
+
+/*
+** Set the LIKEOPT flag on the 2-argument function with the given name.
+*/
+static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
+  FuncDef *pDef;
+  pDef = sqlite3FindFunction(db, zName, sqlite3Strlen30(zName),
+                             2, SQLITE_UTF8, 0);
+  if( ALWAYS(pDef) ){
+    pDef->flags = flagVal;
+  }
+}
+
+/*
+** Register the built-in LIKE and GLOB functions.  The caseSensitive
+** parameter determines whether or not the LIKE operator is case
+** sensitive.  GLOB is always case sensitive.
+*/
+SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){
+  struct compareInfo *pInfo;
+  if( caseSensitive ){
+    pInfo = (struct compareInfo*)&likeInfoAlt;
+  }else{
+    pInfo = (struct compareInfo*)&likeInfoNorm;
+  }
+  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0);
+  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0);
+  sqlite3CreateFunc(db, "glob", 2, SQLITE_ANY, 
+      (struct compareInfo*)&globInfo, likeFunc, 0,0);
+  setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE);
+  setLikeOptFlag(db, "like", 
+      caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE);
+}
+
+/*
+** pExpr points to an expression which implements a function.  If
+** it is appropriate to apply the LIKE optimization to that function
+** then set aWc[0] through aWc[2] to the wildcard characters and
+** return TRUE.  If the function is not a LIKE-style function then
+** return FALSE.
+*/
+SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
+  FuncDef *pDef;
+  if( pExpr->op!=TK_FUNCTION 
+   || !pExpr->x.pList 
+   || pExpr->x.pList->nExpr!=2
+  ){
+    return 0;
+  }
+  assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+  pDef = sqlite3FindFunction(db, pExpr->u.zToken, 
+                             sqlite3Strlen30(pExpr->u.zToken),
+                             2, SQLITE_UTF8, 0);
+  if( NEVER(pDef==0) || (pDef->flags & SQLITE_FUNC_LIKE)==0 ){
+    return 0;
+  }
+
+  /* The memcpy() statement assumes that the wildcard characters are
+  ** the first three statements in the compareInfo structure.  The
+  ** asserts() that follow verify that assumption
+  */
+  memcpy(aWc, pDef->pUserData, 3);
+  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
+  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
+  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );
+  *pIsNocase = (pDef->flags & SQLITE_FUNC_CASE)==0;
+  return 1;
+}
+
+/*
+** All all of the FuncDef structures in the aBuiltinFunc[] array above
+** to the global function hash table.  This occurs at start-time (as
+** a consequence of calling sqlite3_initialize()).
+**
+** After this routine runs
+*/
+SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
+  /*
+  ** The following array holds FuncDef structures for all of the functions
+  ** defined in this file.
+  **
+  ** The array cannot be constant since changes are made to the
+  ** FuncDef.pHash elements at start-time.  The elements of this array
+  ** are read-only after initialization is complete.
+  */
+  static SQLITE_WSD FuncDef aBuiltinFunc[] = {
+    FUNCTION(ltrim,              1, 1, 0, trimFunc         ),
+    FUNCTION(ltrim,              2, 1, 0, trimFunc         ),
+    FUNCTION(rtrim,              1, 2, 0, trimFunc         ),
+    FUNCTION(rtrim,              2, 2, 0, trimFunc         ),
+    FUNCTION(trim,               1, 3, 0, trimFunc         ),
+    FUNCTION(trim,               2, 3, 0, trimFunc         ),
+    FUNCTION(min,               -1, 0, 1, minmaxFunc       ),
+    FUNCTION(min,                0, 0, 1, 0                ),
+    AGGREGATE(min,               1, 0, 1, minmaxStep,      minMaxFinalize ),
+    FUNCTION(max,               -1, 1, 1, minmaxFunc       ),
+    FUNCTION(max,                0, 1, 1, 0                ),
+    AGGREGATE(max,               1, 1, 1, minmaxStep,      minMaxFinalize ),
+    FUNCTION(typeof,             1, 0, 0, typeofFunc       ),
+    FUNCTION(length,             1, 0, 0, lengthFunc       ),
+    FUNCTION(substr,             2, 0, 0, substrFunc       ),
+    FUNCTION(substr,             3, 0, 0, substrFunc       ),
+    FUNCTION(abs,                1, 0, 0, absFunc          ),
+#ifndef SQLITE_OMIT_FLOATING_POINT
+    FUNCTION(round,              1, 0, 0, roundFunc        ),
+    FUNCTION(round,              2, 0, 0, roundFunc        ),
+#endif
+    FUNCTION(upper,              1, 0, 0, upperFunc        ),
+    FUNCTION(lower,              1, 0, 0, lowerFunc        ),
+    FUNCTION(coalesce,           1, 0, 0, 0                ),
+    FUNCTION(coalesce,          -1, 0, 0, ifnullFunc       ),
+    FUNCTION(coalesce,           0, 0, 0, 0                ),
+    FUNCTION(hex,                1, 0, 0, hexFunc          ),
+    FUNCTION(ifnull,             2, 0, 1, ifnullFunc       ),
+    FUNCTION(random,             0, 0, 0, randomFunc       ),
+    FUNCTION(randomblob,         1, 0, 0, randomBlob       ),
+    FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
+    FUNCTION(sqlite_version,     0, 0, 0, versionFunc      ),
+    FUNCTION(sqlite_source_id,   0, 0, 0, sourceidFunc     ),
+    FUNCTION(quote,              1, 0, 0, quoteFunc        ),
+    FUNCTION(last_insert_rowid,  0, 0, 0, last_insert_rowid),
+    FUNCTION(changes,            0, 0, 0, changes          ),
+    FUNCTION(total_changes,      0, 0, 0, total_changes    ),
+    FUNCTION(replace,            3, 0, 0, replaceFunc      ),
+    FUNCTION(zeroblob,           1, 0, 0, zeroblobFunc     ),
+  #ifdef SQLITE_SOUNDEX
+    FUNCTION(soundex,            1, 0, 0, soundexFunc      ),
+  #endif
+  #ifndef SQLITE_OMIT_LOAD_EXTENSION
+    FUNCTION(load_extension,     1, 0, 0, loadExt          ),
+    FUNCTION(load_extension,     2, 0, 0, loadExt          ),
+  #endif
+    AGGREGATE(sum,               1, 0, 0, sumStep,         sumFinalize    ),
+    AGGREGATE(total,             1, 0, 0, sumStep,         totalFinalize    ),
+    AGGREGATE(avg,               1, 0, 0, sumStep,         avgFinalize    ),
+ /* AGGREGATE(count,             0, 0, 0, countStep,       countFinalize  ), */
+    {0,SQLITE_UTF8,SQLITE_FUNC_COUNT,0,0,0,countStep,countFinalize,"count",0},
+    AGGREGATE(count,             1, 0, 0, countStep,       countFinalize  ),
+    AGGREGATE(group_concat,      1, 0, 0, groupConcatStep, groupConcatFinalize),
+    AGGREGATE(group_concat,      2, 0, 0, groupConcatStep, groupConcatFinalize),
+  
+    LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+  #ifdef SQLITE_CASE_SENSITIVE_LIKE
+    LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+    LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+  #else
+    LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE),
+    LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE),
+  #endif
+  };
+
+  int i;
+  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aBuiltinFunc);
+
+  for(i=0; i<ArraySize(aBuiltinFunc); i++){
+    sqlite3FuncDefInsert(pHash, &aFunc[i]);
+  }
+  sqlite3RegisterDateTimeFunctions();
+}
+
+/************** End of func.c ************************************************/
+/************** Begin file fkey.c ********************************************/
+/*
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used by the compiler to add foreign key
+** support to compiled SQL statements.
+*/
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+#ifndef SQLITE_OMIT_TRIGGER
+
+/*
+** Deferred and Immediate FKs
+** --------------------------
+**
+** Foreign keys in SQLite come in two flavours: deferred and immediate.
+** If an immediate foreign key constraint is violated, SQLITE_CONSTRAINT
+** is returned and the current statement transaction rolled back. If a 
+** deferred foreign key constraint is violated, no action is taken 
+** immediately. However if the application attempts to commit the 
+** transaction before fixing the constraint violation, the attempt fails.
+**
+** Deferred constraints are implemented using a simple counter associated
+** with the database handle. The counter is set to zero each time a 
+** database transaction is opened. Each time a statement is executed 
+** that causes a foreign key violation, the counter is incremented. Each
+** time a statement is executed that removes an existing violation from
+** the database, the counter is decremented. When the transaction is
+** committed, the commit fails if the current value of the counter is
+** greater than zero. This scheme has two big drawbacks:
+**
+**   * When a commit fails due to a deferred foreign key constraint, 
+**     there is no way to tell which foreign constraint is not satisfied,
+**     or which row it is not satisfied for.
+**
+**   * If the database contains foreign key violations when the 
+**     transaction is opened, this may cause the mechanism to malfunction.
+**
+** Despite these problems, this approach is adopted as it seems simpler
+** than the alternatives.
+**
+** INSERT operations:
+**
+**   I.1) For each FK for which the table is the child table, search
+**        the parent table for a match. If none is found increment the
+**        constraint counter.
+**
+**   I.2) For each FK for which the table is the parent table, 
+**        search the child table for rows that correspond to the new
+**        row in the parent table. Decrement the counter for each row
+**        found (as the constraint is now satisfied).
+**
+** DELETE operations:
+**
+**   D.1) For each FK for which the table is the child table, 
+**        search the parent table for a row that corresponds to the 
+**        deleted row in the child table. If such a row is not found, 
+**        decrement the counter.
+**
+**   D.2) For each FK for which the table is the parent table, search 
+**        the child table for rows that correspond to the deleted row 
+**        in the parent table. For each found increment the counter.
+**
+** UPDATE operations:
+**
+**   An UPDATE command requires that all 4 steps above are taken, but only
+**   for FK constraints for which the affected columns are actually 
+**   modified (values must be compared at runtime).
+**
+** Note that I.1 and D.1 are very similar operations, as are I.2 and D.2.
+** This simplifies the implementation a bit.
+**
+** For the purposes of immediate FK constraints, the OR REPLACE conflict
+** resolution is considered to delete rows before the new row is inserted.
+** If a delete caused by OR REPLACE violates an FK constraint, an exception
+** is thrown, even if the FK constraint would be satisfied after the new 
+** row is inserted.
+**
+** Immediate constraints are usually handled similarly. The only difference 
+** is that the counter used is stored as part of each individual statement
+** object (struct Vdbe). If, after the statement has run, its immediate
+** constraint counter is greater than zero, it returns SQLITE_CONSTRAINT
+** and the statement transaction is rolled back. An exception is an INSERT
+** statement that inserts a single row only (no triggers). In this case,
+** instead of using a counter, an exception is thrown immediately if the
+** INSERT violates a foreign key constraint. This is necessary as such
+** an INSERT does not open a statement transaction.
+**
+** TODO: How should dropping a table be handled? How should renaming a 
+** table be handled?
+**
+**
+** Query API Notes
+** ---------------
+**
+** Before coding an UPDATE or DELETE row operation, the code-generator
+** for those two operations needs to know whether or not the operation
+** requires any FK processing and, if so, which columns of the original
+** row are required by the FK processing VDBE code (i.e. if FKs were
+** implemented using triggers, which of the old.* columns would be 
+** accessed). No information is required by the code-generator before
+** coding an INSERT operation. The functions used by the UPDATE/DELETE
+** generation code to query for this information are:
+**
+**   sqlite3FkRequired() - Test to see if FK processing is required.
+**   sqlite3FkOldmask()  - Query for the set of required old.* columns.
+**
+**
+** Externally accessible module functions
+** --------------------------------------
+**
+**   sqlite3FkCheck()    - Check for foreign key violations.
+**   sqlite3FkActions()  - Code triggers for ON UPDATE/ON DELETE actions.
+**   sqlite3FkDelete()   - Delete an FKey structure.
+*/
+
+/*
+** VDBE Calling Convention
+** -----------------------
+**
+** Example:
+**
+**   For the following INSERT statement:
+**
+**     CREATE TABLE t1(a, b INTEGER PRIMARY KEY, c);
+**     INSERT INTO t1 VALUES(1, 2, 3.1);
+**
+**   Register (x):        2    (type integer)
+**   Register (x+1):      1    (type integer)
+**   Register (x+2):      NULL (type NULL)
+**   Register (x+3):      3.1  (type real)
+*/
+
+/*
+** A foreign key constraint requires that the key columns in the parent
+** table are collectively subject to a UNIQUE or PRIMARY KEY constraint.
+** Given that pParent is the parent table for foreign key constraint pFKey, 
+** search the schema a unique index on the parent key columns. 
+**
+** If successful, zero is returned. If the parent key is an INTEGER PRIMARY 
+** KEY column, then output variable *ppIdx is set to NULL. Otherwise, *ppIdx 
+** is set to point to the unique index. 
+** 
+** If the parent key consists of a single column (the foreign key constraint
+** is not a composite foreign key), output variable *paiCol is set to NULL.
+** Otherwise, it is set to point to an allocated array of size N, where
+** N is the number of columns in the parent key. The first element of the
+** array is the index of the child table column that is mapped by the FK
+** constraint to the parent table column stored in the left-most column
+** of index *ppIdx. The second element of the array is the index of the
+** child table column that corresponds to the second left-most column of
+** *ppIdx, and so on.
+**
+** If the required index cannot be found, either because:
+**
+**   1) The named parent key columns do not exist, or
+**
+**   2) The named parent key columns do exist, but are not subject to a
+**      UNIQUE or PRIMARY KEY constraint, or
+**
+**   3) No parent key columns were provided explicitly as part of the
+**      foreign key definition, and the parent table does not have a
+**      PRIMARY KEY, or
+**
+**   4) No parent key columns were provided explicitly as part of the
+**      foreign key definition, and the PRIMARY KEY of the parent table 
+**      consists of a a different number of columns to the child key in 
+**      the child table.
+**
+** then non-zero is returned, and a "foreign key mismatch" error loaded
+** into pParse. If an OOM error occurs, non-zero is returned and the
+** pParse->db->mallocFailed flag is set.
+*/
+static int locateFkeyIndex(
+  Parse *pParse,                  /* Parse context to store any error in */
+  Table *pParent,                 /* Parent table of FK constraint pFKey */
+  FKey *pFKey,                    /* Foreign key to find index for */
+  Index **ppIdx,                  /* OUT: Unique index on parent table */
+  int **paiCol                    /* OUT: Map of index columns in pFKey */
+){
+  Index *pIdx = 0;                    /* Value to return via *ppIdx */
+  int *aiCol = 0;                     /* Value to return via *paiCol */
+  int nCol = pFKey->nCol;             /* Number of columns in parent key */
+  char *zKey = pFKey->aCol[0].zCol;   /* Name of left-most parent key column */
+
+  /* The caller is responsible for zeroing output parameters. */
+  assert( ppIdx && *ppIdx==0 );
+  assert( !paiCol || *paiCol==0 );
+  assert( pParse );
+
+  /* If this is a non-composite (single column) foreign key, check if it 
+  ** maps to the INTEGER PRIMARY KEY of table pParent. If so, leave *ppIdx 
+  ** and *paiCol set to zero and return early. 
+  **
+  ** Otherwise, for a composite foreign key (more than one column), allocate
+  ** space for the aiCol array (returned via output parameter *paiCol).
+  ** Non-composite foreign keys do not require the aiCol array.
+  */
+  if( nCol==1 ){
+    /* The FK maps to the IPK if any of the following are true:
+    **
+    **   1) There is an INTEGER PRIMARY KEY column and the FK is implicitly 
+    **      mapped to the primary key of table pParent, or
+    **   2) The FK is explicitly mapped to a column declared as INTEGER
+    **      PRIMARY KEY.
+    */
+    if( pParent->iPKey>=0 ){
+      if( !zKey ) return 0;
+      if( !sqlite3StrICmp(pParent->aCol[pParent->iPKey].zName, zKey) ) return 0;
+    }
+  }else if( paiCol ){
+    assert( nCol>1 );
+    aiCol = (int *)sqlite3DbMallocRaw(pParse->db, nCol*sizeof(int));
+    if( !aiCol ) return 1;
+    *paiCol = aiCol;
+  }
+
+  for(pIdx=pParent->pIndex; pIdx; pIdx=pIdx->pNext){
+    if( pIdx->nColumn==nCol && pIdx->onError!=OE_None ){ 
+      /* pIdx is a UNIQUE index (or a PRIMARY KEY) and has the right number
+      ** of columns. If each indexed column corresponds to a foreign key
+      ** column of pFKey, then this index is a winner.  */
+
+      if( zKey==0 ){
+        /* If zKey is NULL, then this foreign key is implicitly mapped to 
+        ** the PRIMARY KEY of table pParent. The PRIMARY KEY index may be 
+        ** identified by the test (Index.autoIndex==2).  */
+        if( pIdx->autoIndex==2 ){
+          if( aiCol ){
+            int i;
+            for(i=0; i<nCol; i++) aiCol[i] = pFKey->aCol[i].iFrom;
+          }
+          break;
+        }
+      }else{
+        /* If zKey is non-NULL, then this foreign key was declared to
+        ** map to an explicit list of columns in table pParent. Check if this
+        ** index matches those columns. Also, check that the index uses
+        ** the default collation sequences for each column. */
+        int i, j;
+        for(i=0; i<nCol; i++){
+          int iCol = pIdx->aiColumn[i];     /* Index of column in parent tbl */
+          char *zDfltColl;                  /* Def. collation for column */
+          char *zIdxCol;                    /* Name of indexed column */
+
+          /* If the index uses a collation sequence that is different from
+          ** the default collation sequence for the column, this index is
+          ** unusable. Bail out early in this case.  */
+          zDfltColl = pParent->aCol[iCol].zColl;
+          if( !zDfltColl ){
+            zDfltColl = "BINARY";
+          }
+          if( sqlite3StrICmp(pIdx->azColl[i], zDfltColl) ) break;
+
+          zIdxCol = pParent->aCol[iCol].zName;
+          for(j=0; j<nCol; j++){
+            if( sqlite3StrICmp(pFKey->aCol[j].zCol, zIdxCol)==0 ){
+              if( aiCol ) aiCol[i] = pFKey->aCol[j].iFrom;
+              break;
+            }
+          }
+          if( j==nCol ) break;
+        }
+        if( i==nCol ) break;      /* pIdx is usable */
+      }
+    }
+  }
+
+  if( !pIdx ){
+    if( !pParse->disableTriggers ){
+      sqlite3ErrorMsg(pParse, "foreign key mismatch");
+    }
+    sqlite3DbFree(pParse->db, aiCol);
+    return 1;
+  }
+
+  *ppIdx = pIdx;
+  return 0;
+}
+
+/*
+** This function is called when a row is inserted into or deleted from the 
+** child table of foreign key constraint pFKey. If an SQL UPDATE is executed 
+** on the child table of pFKey, this function is invoked twice for each row
+** affected - once to "delete" the old row, and then again to "insert" the
+** new row.
+**
+** Each time it is called, this function generates VDBE code to locate the
+** row in the parent table that corresponds to the row being inserted into 
+** or deleted from the child table. If the parent row can be found, no 
+** special action is taken. Otherwise, if the parent row can *not* be
+** found in the parent table:
+**
+**   Operation | FK type   | Action taken
+**   --------------------------------------------------------------------------
+**   INSERT      immediate   Increment the "immediate constraint counter".
+**
+**   DELETE      immediate   Decrement the "immediate constraint counter".
+**
+**   INSERT      deferred    Increment the "deferred constraint counter".
+**
+**   DELETE      deferred    Decrement the "deferred constraint counter".
+**
+** These operations are identified in the comment at the top of this file 
+** (fkey.c) as "I.1" and "D.1".
+*/
+static void fkLookupParent(
+  Parse *pParse,        /* Parse context */
+  int iDb,              /* Index of database housing pTab */
+  Table *pTab,          /* Parent table of FK pFKey */
+  Index *pIdx,          /* Unique index on parent key columns in pTab */
+  FKey *pFKey,          /* Foreign key constraint */
+  int *aiCol,           /* Map from parent key columns to child table columns */
+  int regData,          /* Address of array containing child table row */
+  int nIncr,            /* Increment constraint counter by this */
+  int isIgnore          /* If true, pretend pTab contains all NULL values */
+){
+  int i;                                    /* Iterator variable */
+  Vdbe *v = sqlite3GetVdbe(pParse);         /* Vdbe to add code to */
+  int iCur = pParse->nTab - 1;              /* Cursor number to use */
+  int iOk = sqlite3VdbeMakeLabel(v);        /* jump here if parent key found */
+
+  /* If nIncr is less than zero, then check at runtime if there are any
+  ** outstanding constraints to resolve. If there are not, there is no need
+  ** to check if deleting this row resolves any outstanding violations.
+  **
+  ** Check if any of the key columns in the child table row are NULL. If 
+  ** any are, then the constraint is considered satisfied. No need to 
+  ** search for a matching row in the parent table.  */
+  if( nIncr<0 ){
+    sqlite3VdbeAddOp2(v, OP_FkIfZero, pFKey->isDeferred, iOk);
+  }
+  for(i=0; i<pFKey->nCol; i++){
+    int iReg = aiCol[i] + regData + 1;
+    sqlite3VdbeAddOp2(v, OP_IsNull, iReg, iOk);
+  }
+
+  if( isIgnore==0 ){
+    if( pIdx==0 ){
+      /* If pIdx is NULL, then the parent key is the INTEGER PRIMARY KEY
+      ** column of the parent table (table pTab).  */
+      int iMustBeInt;               /* Address of MustBeInt instruction */
+      int regTemp = sqlite3GetTempReg(pParse);
+  
+      /* Invoke MustBeInt to coerce the child key value to an integer (i.e. 
+      ** apply the affinity of the parent key). If this fails, then there
+      ** is no matching parent key. Before using MustBeInt, make a copy of
+      ** the value. Otherwise, the value inserted into the child key column
+      ** will have INTEGER affinity applied to it, which may not be correct.  */
+      sqlite3VdbeAddOp2(v, OP_SCopy, aiCol[0]+1+regData, regTemp);
+      iMustBeInt = sqlite3VdbeAddOp2(v, OP_MustBeInt, regTemp, 0);
+  
+      /* If the parent table is the same as the child table, and we are about
+      ** to increment the constraint-counter (i.e. this is an INSERT operation),
+      ** then check if the row being inserted matches itself. If so, do not
+      ** increment the constraint-counter.  */
+      if( pTab==pFKey->pFrom && nIncr==1 ){
+        sqlite3VdbeAddOp3(v, OP_Eq, regData, iOk, regTemp);
+      }
+  
+      sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
+      sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regTemp);
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
+      sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
+      sqlite3VdbeJumpHere(v, iMustBeInt);
+      sqlite3ReleaseTempReg(pParse, regTemp);
+    }else{
+      int nCol = pFKey->nCol;
+      int regTemp = sqlite3GetTempRange(pParse, nCol);
+      int regRec = sqlite3GetTempReg(pParse);
+      KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
+  
+      sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb);
+      sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF);
+      for(i=0; i<nCol; i++){
+        sqlite3VdbeAddOp2(v, OP_SCopy, aiCol[i]+1+regData, regTemp+i);
+      }
+  
+      /* If the parent table is the same as the child table, and we are about
+      ** to increment the constraint-counter (i.e. this is an INSERT operation),
+      ** then check if the row being inserted matches itself. If so, do not
+      ** increment the constraint-counter.  */
+      if( pTab==pFKey->pFrom && nIncr==1 ){
+        int iJump = sqlite3VdbeCurrentAddr(v) + nCol + 1;
+        for(i=0; i<nCol; i++){
+          int iChild = aiCol[i]+1+regData;
+          int iParent = pIdx->aiColumn[i]+1+regData;
+          sqlite3VdbeAddOp3(v, OP_Ne, iChild, iJump, iParent);
+        }
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
+      }
+  
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, regTemp, nCol, regRec);
+      sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v, pIdx), 0);
+      sqlite3VdbeAddOp3(v, OP_Found, iCur, iOk, regRec);
+  
+      sqlite3ReleaseTempReg(pParse, regRec);
+      sqlite3ReleaseTempRange(pParse, regTemp, nCol);
+    }
+  }
+
+  if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+    /* Special case: If this is an INSERT statement that will insert exactly
+    ** one row into the table, raise a constraint immediately instead of
+    ** incrementing a counter. This is necessary as the VM code is being
+    ** generated for will not open a statement transaction.  */
+    assert( nIncr==1 );
+    sqlite3HaltConstraint(
+        pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
+    );
+  }else{
+    if( nIncr>0 && pFKey->isDeferred==0 ){
+      sqlite3ParseToplevel(pParse)->mayAbort = 1;
+    }
+    sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
+  }
+
+  sqlite3VdbeResolveLabel(v, iOk);
+  sqlite3VdbeAddOp1(v, OP_Close, iCur);
+}
+
+/*
+** This function is called to generate code executed when a row is deleted
+** from the parent table of foreign key constraint pFKey and, if pFKey is 
+** deferred, when a row is inserted into the same table. When generating
+** code for an SQL UPDATE operation, this function may be called twice -
+** once to "delete" the old row and once to "insert" the new row.
+**
+** The code generated by this function scans through the rows in the child
+** table that correspond to the parent table row being deleted or inserted.
+** For each child row found, one of the following actions is taken:
+**
+**   Operation | FK type   | Action taken
+**   --------------------------------------------------------------------------
+**   DELETE      immediate   Increment the "immediate constraint counter".
+**                           Or, if the ON (UPDATE|DELETE) action is RESTRICT,
+**                           throw a "foreign key constraint failed" exception.
+**
+**   INSERT      immediate   Decrement the "immediate constraint counter".
+**
+**   DELETE      deferred    Increment the "deferred constraint counter".
+**                           Or, if the ON (UPDATE|DELETE) action is RESTRICT,
+**                           throw a "foreign key constraint failed" exception.
+**
+**   INSERT      deferred    Decrement the "deferred constraint counter".
+**
+** These operations are identified in the comment at the top of this file 
+** (fkey.c) as "I.2" and "D.2".
+*/
+static void fkScanChildren(
+  Parse *pParse,                  /* Parse context */
+  SrcList *pSrc,                  /* SrcList containing the table to scan */
+  Table *pTab,
+  Index *pIdx,                    /* Foreign key index */
+  FKey *pFKey,                    /* Foreign key relationship */
+  int *aiCol,                     /* Map from pIdx cols to child table cols */
+  int regData,                    /* Referenced table data starts here */
+  int nIncr                       /* Amount to increment deferred counter by */
+){
+  sqlite3 *db = pParse->db;       /* Database handle */
+  int i;                          /* Iterator variable */
+  Expr *pWhere = 0;               /* WHERE clause to scan with */
+  NameContext sNameContext;       /* Context used to resolve WHERE clause */
+  WhereInfo *pWInfo;              /* Context used by sqlite3WhereXXX() */
+  int iFkIfZero = 0;              /* Address of OP_FkIfZero */
+  Vdbe *v = sqlite3GetVdbe(pParse);
+
+  assert( !pIdx || pIdx->pTable==pTab );
+
+  if( nIncr<0 ){
+    iFkIfZero = sqlite3VdbeAddOp2(v, OP_FkIfZero, pFKey->isDeferred, 0);
+  }
+
+  /* Create an Expr object representing an SQL expression like:
+  **
+  **   <parent-key1> = <child-key1> AND <parent-key2> = <child-key2> ...
+  **
+  ** The collation sequence used for the comparison should be that of
+  ** the parent key columns. The affinity of the parent key column should
+  ** be applied to each child key value before the comparison takes place.
+  */
+  for(i=0; i<pFKey->nCol; i++){
+    Expr *pLeft;                  /* Value from parent table row */
+    Expr *pRight;                 /* Column ref to child table */
+    Expr *pEq;                    /* Expression (pLeft = pRight) */
+    int iCol;                     /* Index of column in child table */ 
+    const char *zCol;             /* Name of column in child table */
+
+    pLeft = sqlite3Expr(db, TK_REGISTER, 0);
+    if( pLeft ){
+      /* Set the collation sequence and affinity of the LHS of each TK_EQ
+      ** expression to the parent key column defaults.  */
+      if( pIdx ){
+        Column *pCol;
+        iCol = pIdx->aiColumn[i];
+        pCol = &pIdx->pTable->aCol[iCol];
+        pLeft->iTable = regData+iCol+1;
+        pLeft->affinity = pCol->affinity;
+        pLeft->pColl = sqlite3LocateCollSeq(pParse, pCol->zColl);
+      }else{
+        pLeft->iTable = regData;
+        pLeft->affinity = SQLITE_AFF_INTEGER;
+      }
+    }
+    iCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom;
+    assert( iCol>=0 );
+    zCol = pFKey->pFrom->aCol[iCol].zName;
+    pRight = sqlite3Expr(db, TK_ID, zCol);
+    pEq = sqlite3PExpr(pParse, TK_EQ, pLeft, pRight, 0);
+    pWhere = sqlite3ExprAnd(db, pWhere, pEq);
+  }
+
+  /* If the child table is the same as the parent table, and this scan
+  ** is taking place as part of a DELETE operation (operation D.2), omit the
+  ** row being deleted from the scan by adding ($rowid != rowid) to the WHERE 
+  ** clause, where $rowid is the rowid of the row being deleted.  */
+  if( pTab==pFKey->pFrom && nIncr>0 ){
+    Expr *pEq;                    /* Expression (pLeft = pRight) */
+    Expr *pLeft;                  /* Value from parent table row */
+    Expr *pRight;                 /* Column ref to child table */
+    pLeft = sqlite3Expr(db, TK_REGISTER, 0);
+    pRight = sqlite3Expr(db, TK_COLUMN, 0);
+    if( pLeft && pRight ){
+      pLeft->iTable = regData;
+      pLeft->affinity = SQLITE_AFF_INTEGER;
+      pRight->iTable = pSrc->a[0].iCursor;
+      pRight->iColumn = -1;
+    }
+    pEq = sqlite3PExpr(pParse, TK_NE, pLeft, pRight, 0);
+    pWhere = sqlite3ExprAnd(db, pWhere, pEq);
+  }
+
+  /* Resolve the references in the WHERE clause. */
+  memset(&sNameContext, 0, sizeof(NameContext));
+  sNameContext.pSrcList = pSrc;
+  sNameContext.pParse = pParse;
+  sqlite3ResolveExprNames(&sNameContext, pWhere);
+
+  /* Create VDBE to loop through the entries in pSrc that match the WHERE
+  ** clause. If the constraint is not deferred, throw an exception for
+  ** each row found. Otherwise, for deferred constraints, increment the
+  ** deferred constraint counter by nIncr for each row selected.  */
+  pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0);
+  if( nIncr>0 && pFKey->isDeferred==0 ){
+    sqlite3ParseToplevel(pParse)->mayAbort = 1;
+  }
+  sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
+  if( pWInfo ){
+    sqlite3WhereEnd(pWInfo);
+  }
+
+  /* Clean up the WHERE clause constructed above. */
+  sqlite3ExprDelete(db, pWhere);
+  if( iFkIfZero ){
+    sqlite3VdbeJumpHere(v, iFkIfZero);
+  }
+}
+
+/*
+** This function returns a pointer to the head of a linked list of FK
+** constraints for which table pTab is the parent table. For example,
+** given the following schema:
+**
+**   CREATE TABLE t1(a PRIMARY KEY);
+**   CREATE TABLE t2(b REFERENCES t1(a);
+**
+** Calling this function with table "t1" as an argument returns a pointer
+** to the FKey structure representing the foreign key constraint on table
+** "t2". Calling this function with "t2" as the argument would return a
+** NULL pointer (as there are no FK constraints for which t2 is the parent
+** table).
+*/
+SQLITE_PRIVATE FKey *sqlite3FkReferences(Table *pTab){
+  int nName = sqlite3Strlen30(pTab->zName);
+  return (FKey *)sqlite3HashFind(&pTab->pSchema->fkeyHash, pTab->zName, nName);
+}
+
+/*
+** The second argument is a Trigger structure allocated by the 
+** fkActionTrigger() routine. This function deletes the Trigger structure
+** and all of its sub-components.
+**
+** The Trigger structure or any of its sub-components may be allocated from
+** the lookaside buffer belonging to database handle dbMem.
+*/
+static void fkTriggerDelete(sqlite3 *dbMem, Trigger *p){
+  if( p ){
+    TriggerStep *pStep = p->step_list;
+    sqlite3ExprDelete(dbMem, pStep->pWhere);
+    sqlite3ExprListDelete(dbMem, pStep->pExprList);
+    sqlite3SelectDelete(dbMem, pStep->pSelect);
+    sqlite3ExprDelete(dbMem, p->pWhen);
+    sqlite3DbFree(dbMem, p);
+  }
+}
+
+/*
+** This function is called to generate code that runs when table pTab is
+** being dropped from the database. The SrcList passed as the second argument
+** to this function contains a single entry guaranteed to resolve to
+** table pTab.
+**
+** Normally, no code is required. However, if either
+**
+**   (a) The table is the parent table of a FK constraint, or
+**   (b) The table is the child table of a deferred FK constraint and it is
+**       determined at runtime that there are outstanding deferred FK 
+**       constraint violations in the database,
+**
+** then the equivalent of "DELETE FROM <tbl>" is executed before dropping
+** the table from the database. Triggers are disabled while running this
+** DELETE, but foreign key actions are not.
+*/
+SQLITE_PRIVATE void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTab){
+  sqlite3 *db = pParse->db;
+  if( (db->flags&SQLITE_ForeignKeys) && !IsVirtual(pTab) && !pTab->pSelect ){
+    int iSkip = 0;
+    Vdbe *v = sqlite3GetVdbe(pParse);
+
+    assert( v );                  /* VDBE has already been allocated */
+    if( sqlite3FkReferences(pTab)==0 ){
+      /* Search for a deferred foreign key constraint for which this table
+      ** is the child table. If one cannot be found, return without 
+      ** generating any VDBE code. If one can be found, then jump over
+      ** the entire DELETE if there are no outstanding deferred constraints
+      ** when this statement is run.  */
+      FKey *p;
+      for(p=pTab->pFKey; p; p=p->pNextFrom){
+        if( p->isDeferred ) break;
+      }
+      if( !p ) return;
+      iSkip = sqlite3VdbeMakeLabel(v);
+      sqlite3VdbeAddOp2(v, OP_FkIfZero, 1, iSkip);
+    }
+
+    pParse->disableTriggers = 1;
+    sqlite3DeleteFrom(pParse, sqlite3SrcListDup(db, pName, 0), 0);
+    pParse->disableTriggers = 0;
+
+    /* If the DELETE has generated immediate foreign key constraint 
+    ** violations, halt the VDBE and return an error at this point, before
+    ** any modifications to the schema are made. This is because statement
+    ** transactions are not able to rollback schema changes.  */
+    sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2);
+    sqlite3HaltConstraint(
+        pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
+    );
+
+    if( iSkip ){
+      sqlite3VdbeResolveLabel(v, iSkip);
+    }
+  }
+}
+
+/*
+** This function is called when inserting, deleting or updating a row of
+** table pTab to generate VDBE code to perform foreign key constraint 
+** processing for the operation.
+**
+** For a DELETE operation, parameter regOld is passed the index of the
+** first register in an array of (pTab->nCol+1) registers containing the
+** rowid of the row being deleted, followed by each of the column values
+** of the row being deleted, from left to right. Parameter regNew is passed
+** zero in this case.
+**
+** For an INSERT operation, regOld is passed zero and regNew is passed the
+** first register of an array of (pTab->nCol+1) registers containing the new
+** row data.
+**
+** For an UPDATE operation, this function is called twice. Once before
+** the original record is deleted from the table using the calling convention
+** described for DELETE. Then again after the original record is deleted
+** but before the new record is inserted using the INSERT convention. 
+*/
+SQLITE_PRIVATE void sqlite3FkCheck(
+  Parse *pParse,                  /* Parse context */
+  Table *pTab,                    /* Row is being deleted from this table */ 
+  int regOld,                     /* Previous row data is stored here */
+  int regNew                      /* New row data is stored here */
+){
+  sqlite3 *db = pParse->db;       /* Database handle */
+  Vdbe *v;                        /* VM to write code to */
+  FKey *pFKey;                    /* Used to iterate through FKs */
+  int iDb;                        /* Index of database containing pTab */
+  const char *zDb;                /* Name of database containing pTab */
+  int isIgnoreErrors = pParse->disableTriggers;
+
+  /* Exactly one of regOld and regNew should be non-zero. */
+  assert( (regOld==0)!=(regNew==0) );
+
+  /* If foreign-keys are disabled, this function is a no-op. */
+  if( (db->flags&SQLITE_ForeignKeys)==0 ) return;
+
+  v = sqlite3GetVdbe(pParse);
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  zDb = db->aDb[iDb].zName;
+
+  /* Loop through all the foreign key constraints for which pTab is the
+  ** child table (the table that the foreign key definition is part of).  */
+  for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){
+    Table *pTo;                   /* Parent table of foreign key pFKey */
+    Index *pIdx = 0;              /* Index on key columns in pTo */
+    int *aiFree = 0;
+    int *aiCol;
+    int iCol;
+    int i;
+    int isIgnore = 0;
+
+    /* Find the parent table of this foreign key. Also find a unique index 
+    ** on the parent key columns in the parent table. If either of these 
+    ** schema items cannot be located, set an error in pParse and return 
+    ** early.  */
+    if( pParse->disableTriggers ){
+      pTo = sqlite3FindTable(db, pFKey->zTo, zDb);
+    }else{
+      pTo = sqlite3LocateTable(pParse, 0, pFKey->zTo, zDb);
+    }
+    if( !pTo || locateFkeyIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){
+      if( !isIgnoreErrors || db->mallocFailed ) return;
+      continue;
+    }
+    assert( pFKey->nCol==1 || (aiFree && pIdx) );
+
+    if( aiFree ){
+      aiCol = aiFree;
+    }else{
+      iCol = pFKey->aCol[0].iFrom;
+      aiCol = &iCol;
+    }
+    for(i=0; i<pFKey->nCol; i++){
+      if( aiCol[i]==pTab->iPKey ){
+        aiCol[i] = -1;
+      }
+#ifndef SQLITE_OMIT_AUTHORIZATION
+      /* Request permission to read the parent key columns. If the 
+      ** authorization callback returns SQLITE_IGNORE, behave as if any
+      ** values read from the parent table are NULL. */
+      if( db->xAuth ){
+        int rcauth;
+        char *zCol = pTo->aCol[pIdx ? pIdx->aiColumn[i] : pTo->iPKey].zName;
+        rcauth = sqlite3AuthReadCol(pParse, pTo->zName, zCol, iDb);
+        isIgnore = (rcauth==SQLITE_IGNORE);
+      }
+#endif
+    }
+
+    /* Take a shared-cache advisory read-lock on the parent table. Allocate 
+    ** a cursor to use to search the unique index on the parent key columns 
+    ** in the parent table.  */
+    sqlite3TableLock(pParse, iDb, pTo->tnum, 0, pTo->zName);
+    pParse->nTab++;
+
+    if( regOld!=0 ){
+      /* A row is being removed from the child table. Search for the parent.
+      ** If the parent does not exist, removing the child row resolves an 
+      ** outstanding foreign key constraint violation. */
+      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regOld, -1,isIgnore);
+    }
+    if( regNew!=0 ){
+      /* A row is being added to the child table. If a parent row cannot
+      ** be found, adding the child row has violated the FK constraint. */ 
+      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regNew, +1,isIgnore);
+    }
+
+    sqlite3DbFree(db, aiFree);
+  }
+
+  /* Loop through all the foreign key constraints that refer to this table */
+  for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){
+    Index *pIdx = 0;              /* Foreign key index for pFKey */
+    SrcList *pSrc;
+    int *aiCol = 0;
+
+    if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+      assert( regOld==0 && regNew!=0 );
+      /* Inserting a single row into a parent table cannot cause an immediate
+      ** foreign key violation. So do nothing in this case.  */
+      continue;
+    }
+
+    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){
+      if( !isIgnoreErrors || db->mallocFailed ) return;
+      continue;
+    }
+    assert( aiCol || pFKey->nCol==1 );
+
+    /* Create a SrcList structure containing a single table (the table 
+    ** the foreign key that refers to this table is attached to). This
+    ** is required for the sqlite3WhereXXX() interface.  */
+    pSrc = sqlite3SrcListAppend(db, 0, 0, 0);
+    if( pSrc ){
+      struct SrcList_item *pItem = pSrc->a;
+      pItem->pTab = pFKey->pFrom;
+      pItem->zName = pFKey->pFrom->zName;
+      pItem->pTab->nRef++;
+      pItem->iCursor = pParse->nTab++;
+  
+      if( regNew!=0 ){
+        fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regNew, -1);
+      }
+      if( regOld!=0 ){
+        /* If there is a RESTRICT action configured for the current operation
+        ** on the parent table of this FK, then throw an exception 
+        ** immediately if the FK constraint is violated, even if this is a
+        ** deferred trigger. That's what RESTRICT means. To defer checking
+        ** the constraint, the FK should specify NO ACTION (represented
+        ** using OE_None). NO ACTION is the default.  */
+        fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regOld, 1);
+      }
+      pItem->zName = 0;
+      sqlite3SrcListDelete(db, pSrc);
+    }
+    sqlite3DbFree(db, aiCol);
+  }
+}
+
+#define COLUMN_MASK(x) (((x)>31) ? 0xffffffff : ((u32)1<<(x)))
+
+/*
+** This function is called before generating code to update or delete a 
+** row contained in table pTab.
+*/
+SQLITE_PRIVATE u32 sqlite3FkOldmask(
+  Parse *pParse,                  /* Parse context */
+  Table *pTab                     /* Table being modified */
+){
+  u32 mask = 0;
+  if( pParse->db->flags&SQLITE_ForeignKeys ){
+    FKey *p;
+    int i;
+    for(p=pTab->pFKey; p; p=p->pNextFrom){
+      for(i=0; i<p->nCol; i++) mask |= COLUMN_MASK(p->aCol[i].iFrom);
+    }
+    for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
+      Index *pIdx = 0;
+      locateFkeyIndex(pParse, pTab, p, &pIdx, 0);
+      if( pIdx ){
+        for(i=0; i<pIdx->nColumn; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]);
+      }
+    }
+  }
+  return mask;
+}
+
+/*
+** This function is called before generating code to update or delete a 
+** row contained in table pTab. If the operation is a DELETE, then
+** parameter aChange is passed a NULL value. For an UPDATE, aChange points
+** to an array of size N, where N is the number of columns in table pTab.
+** If the i'th column is not modified by the UPDATE, then the corresponding 
+** entry in the aChange[] array is set to -1. If the column is modified,
+** the value is 0 or greater. Parameter chngRowid is set to true if the
+** UPDATE statement modifies the rowid fields of the table.
+**
+** If any foreign key processing will be required, this function returns
+** true. If there is no foreign key related processing, this function 
+** returns false.
+*/
+SQLITE_PRIVATE int sqlite3FkRequired(
+  Parse *pParse,                  /* Parse context */
+  Table *pTab,                    /* Table being modified */
+  int *aChange,                   /* Non-NULL for UPDATE operations */
+  int chngRowid                   /* True for UPDATE that affects rowid */
+){
+  if( pParse->db->flags&SQLITE_ForeignKeys ){
+    if( !aChange ){
+      /* A DELETE operation. Foreign key processing is required if the 
+      ** table in question is either the child or parent table for any 
+      ** foreign key constraint.  */
+      return (sqlite3FkReferences(pTab) || pTab->pFKey);
+    }else{
+      /* This is an UPDATE. Foreign key processing is only required if the
+      ** operation modifies one or more child or parent key columns. */
+      int i;
+      FKey *p;
+
+      /* Check if any child key columns are being modified. */
+      for(p=pTab->pFKey; p; p=p->pNextFrom){
+        for(i=0; i<p->nCol; i++){
+          int iChildKey = p->aCol[i].iFrom;
+          if( aChange[iChildKey]>=0 ) return 1;
+          if( iChildKey==pTab->iPKey && chngRowid ) return 1;
+        }
+      }
+
+      /* Check if any parent key columns are being modified. */
+      for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
+        for(i=0; i<p->nCol; i++){
+          char *zKey = p->aCol[i].zCol;
+          int iKey;
+          for(iKey=0; iKey<pTab->nCol; iKey++){
+            Column *pCol = &pTab->aCol[iKey];
+            if( (zKey ? !sqlite3StrICmp(pCol->zName, zKey) : pCol->isPrimKey) ){
+              if( aChange[iKey]>=0 ) return 1;
+              if( iKey==pTab->iPKey && chngRowid ) return 1;
+            }
+          }
+        }
+      }
+    }
+  }
+  return 0;
+}
+
+/*
+** This function is called when an UPDATE or DELETE operation is being 
+** compiled on table pTab, which is the parent table of foreign-key pFKey.
+** If the current operation is an UPDATE, then the pChanges parameter is
+** passed a pointer to the list of columns being modified. If it is a
+** DELETE, pChanges is passed a NULL pointer.
+**
+** It returns a pointer to a Trigger structure containing a trigger
+** equivalent to the ON UPDATE or ON DELETE action specified by pFKey.
+** If the action is "NO ACTION" or "RESTRICT", then a NULL pointer is
+** returned (these actions require no special handling by the triggers
+** sub-system, code for them is created by fkScanChildren()).
+**
+** For example, if pFKey is the foreign key and pTab is table "p" in 
+** the following schema:
+**
+**   CREATE TABLE p(pk PRIMARY KEY);
+**   CREATE TABLE c(ck REFERENCES p ON DELETE CASCADE);
+**
+** then the returned trigger structure is equivalent to:
+**
+**   CREATE TRIGGER ... DELETE ON p BEGIN
+**     DELETE FROM c WHERE ck = old.pk;
+**   END;
+**
+** The returned pointer is cached as part of the foreign key object. It
+** is eventually freed along with the rest of the foreign key object by 
+** sqlite3FkDelete().
+*/
+static Trigger *fkActionTrigger(
+  Parse *pParse,                  /* Parse context */
+  Table *pTab,                    /* Table being updated or deleted from */
+  FKey *pFKey,                    /* Foreign key to get action for */
+  ExprList *pChanges              /* Change-list for UPDATE, NULL for DELETE */
+){
+  sqlite3 *db = pParse->db;       /* Database handle */
+  int action;                     /* One of OE_None, OE_Cascade etc. */
+  Trigger *pTrigger;              /* Trigger definition to return */
+  int iAction = (pChanges!=0);    /* 1 for UPDATE, 0 for DELETE */
+
+  action = pFKey->aAction[iAction];
+  pTrigger = pFKey->apTrigger[iAction];
+
+  if( action!=OE_None && !pTrigger ){
+    u8 enableLookaside;           /* Copy of db->lookaside.bEnabled */
+    char const *zFrom;            /* Name of child table */
+    int nFrom;                    /* Length in bytes of zFrom */
+    Index *pIdx = 0;              /* Parent key index for this FK */
+    int *aiCol = 0;               /* child table cols -> parent key cols */
+    TriggerStep *pStep = 0;        /* First (only) step of trigger program */
+    Expr *pWhere = 0;             /* WHERE clause of trigger step */
+    ExprList *pList = 0;          /* Changes list if ON UPDATE CASCADE */
+    Select *pSelect = 0;          /* If RESTRICT, "SELECT RAISE(...)" */
+    int i;                        /* Iterator variable */
+    Expr *pWhen = 0;              /* WHEN clause for the trigger */
+
+    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0;
+    assert( aiCol || pFKey->nCol==1 );
+
+    for(i=0; i<pFKey->nCol; i++){
+      Token tOld = { "old", 3 };  /* Literal "old" token */
+      Token tNew = { "new", 3 };  /* Literal "new" token */
+      Token tFromCol;             /* Name of column in child table */
+      Token tToCol;               /* Name of column in parent table */
+      int iFromCol;               /* Idx of column in child table */
+      Expr *pEq;                  /* tFromCol = OLD.tToCol */
+
+      iFromCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom;
+      assert( iFromCol>=0 );
+      tToCol.z = pIdx ? pTab->aCol[pIdx->aiColumn[i]].zName : "oid";
+      tFromCol.z = pFKey->pFrom->aCol[iFromCol].zName;
+
+      tToCol.n = sqlite3Strlen30(tToCol.z);
+      tFromCol.n = sqlite3Strlen30(tFromCol.z);
+
+      /* Create the expression "OLD.zToCol = zFromCol". It is important
+      ** that the "OLD.zToCol" term is on the LHS of the = operator, so
+      ** that the affinity and collation sequence associated with the
+      ** parent table are used for the comparison. */
+      pEq = sqlite3PExpr(pParse, TK_EQ,
+          sqlite3PExpr(pParse, TK_DOT, 
+            sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
+            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
+          , 0),
+          sqlite3PExpr(pParse, TK_ID, 0, 0, &tFromCol)
+      , 0);
+      pWhere = sqlite3ExprAnd(db, pWhere, pEq);
+
+      /* For ON UPDATE, construct the next term of the WHEN clause.
+      ** The final WHEN clause will be like this:
+      **
+      **    WHEN NOT(old.col1 IS new.col1 AND ... AND old.colN IS new.colN)
+      */
+      if( pChanges ){
+        pEq = sqlite3PExpr(pParse, TK_IS,
+            sqlite3PExpr(pParse, TK_DOT, 
+              sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
+              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
+              0),
+            sqlite3PExpr(pParse, TK_DOT, 
+              sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
+              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
+              0),
+            0);
+        pWhen = sqlite3ExprAnd(db, pWhen, pEq);
+      }
+  
+      if( action!=OE_Restrict && (action!=OE_Cascade || pChanges) ){
+        Expr *pNew;
+        if( action==OE_Cascade ){
+          pNew = sqlite3PExpr(pParse, TK_DOT, 
+            sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
+            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
+          , 0);
+        }else if( action==OE_SetDflt ){
+          Expr *pDflt = pFKey->pFrom->aCol[iFromCol].pDflt;
+          if( pDflt ){
+            pNew = sqlite3ExprDup(db, pDflt, 0);
+          }else{
+            pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
+          }
+        }else{
+          pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
+        }
+        pList = sqlite3ExprListAppend(pParse, pList, pNew);
+        sqlite3ExprListSetName(pParse, pList, &tFromCol, 0);
+      }
+    }
+    sqlite3DbFree(db, aiCol);
+
+    zFrom = pFKey->pFrom->zName;
+    nFrom = sqlite3Strlen30(zFrom);
+
+    if( action==OE_Restrict ){
+      Token tFrom;
+      Expr *pRaise; 
+
+      tFrom.z = zFrom;
+      tFrom.n = nFrom;
+      pRaise = sqlite3Expr(db, TK_RAISE, "foreign key constraint failed");
+      if( pRaise ){
+        pRaise->affinity = OE_Abort;
+      }
+      pSelect = sqlite3SelectNew(pParse, 
+          sqlite3ExprListAppend(pParse, 0, pRaise),
+          sqlite3SrcListAppend(db, 0, &tFrom, 0),
+          pWhere,
+          0, 0, 0, 0, 0, 0
+      );
+      pWhere = 0;
+    }
+
+    /* In the current implementation, pTab->dbMem==0 for all tables except
+    ** for temporary tables used to describe subqueries.  And temporary
+    ** tables do not have foreign key constraints.  Hence, pTab->dbMem
+    ** should always be 0 there.
+    */
+    enableLookaside = db->lookaside.bEnabled;
+    db->lookaside.bEnabled = 0;
+
+    pTrigger = (Trigger *)sqlite3DbMallocZero(db, 
+        sizeof(Trigger) +         /* struct Trigger */
+        sizeof(TriggerStep) +     /* Single step in trigger program */
+        nFrom + 1                 /* Space for pStep->target.z */
+    );
+    if( pTrigger ){
+      pStep = pTrigger->step_list = (TriggerStep *)&pTrigger[1];
+      pStep->target.z = (char *)&pStep[1];
+      pStep->target.n = nFrom;
+      memcpy((char *)pStep->target.z, zFrom, nFrom);
+  
+      pStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
+      pStep->pExprList = sqlite3ExprListDup(db, pList, EXPRDUP_REDUCE);
+      pStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
+      if( pWhen ){
+        pWhen = sqlite3PExpr(pParse, TK_NOT, pWhen, 0, 0);
+        pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
+      }
+    }
+
+    /* Re-enable the lookaside buffer, if it was disabled earlier. */
+    db->lookaside.bEnabled = enableLookaside;
+
+    sqlite3ExprDelete(db, pWhere);
+    sqlite3ExprDelete(db, pWhen);
+    sqlite3ExprListDelete(db, pList);
+    sqlite3SelectDelete(db, pSelect);
+    if( db->mallocFailed==1 ){
+      fkTriggerDelete(db, pTrigger);
+      return 0;
+    }
+
+    switch( action ){
+      case OE_Restrict:
+        pStep->op = TK_SELECT; 
+        break;
+      case OE_Cascade: 
+        if( !pChanges ){ 
+          pStep->op = TK_DELETE; 
+          break; 
+        }
+      default:
+        pStep->op = TK_UPDATE;
+    }
+    pStep->pTrig = pTrigger;
+    pTrigger->pSchema = pTab->pSchema;
+    pTrigger->pTabSchema = pTab->pSchema;
+    pFKey->apTrigger[iAction] = pTrigger;
+    pTrigger->op = (pChanges ? TK_UPDATE : TK_DELETE);
+  }
+
+  return pTrigger;
+}
+
+/*
+** This function is called when deleting or updating a row to implement
+** any required CASCADE, SET NULL or SET DEFAULT actions.
+*/
+SQLITE_PRIVATE void sqlite3FkActions(
+  Parse *pParse,                  /* Parse context */
+  Table *pTab,                    /* Table being updated or deleted from */
+  ExprList *pChanges,             /* Change-list for UPDATE, NULL for DELETE */
+  int regOld                      /* Address of array containing old row */
+){
+  /* If foreign-key support is enabled, iterate through all FKs that 
+  ** refer to table pTab. If there is an action associated with the FK 
+  ** for this operation (either update or delete), invoke the associated 
+  ** trigger sub-program.  */
+  if( pParse->db->flags&SQLITE_ForeignKeys ){
+    FKey *pFKey;                  /* Iterator variable */
+    for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){
+      Trigger *pAction = fkActionTrigger(pParse, pTab, pFKey, pChanges);
+      if( pAction ){
+        sqlite3CodeRowTriggerDirect(pParse, pAction, pTab, regOld, OE_Abort, 0);
+      }
+    }
+  }
+}
+
+#endif /* ifndef SQLITE_OMIT_TRIGGER */
+
+/*
+** Free all memory associated with foreign key definitions attached to
+** table pTab. Remove the deleted foreign keys from the Schema.fkeyHash
+** hash table.
+*/
+SQLITE_PRIVATE void sqlite3FkDelete(Table *pTab){
+  FKey *pFKey;                    /* Iterator variable */
+  FKey *pNext;                    /* Copy of pFKey->pNextFrom */
+
+  for(pFKey=pTab->pFKey; pFKey; pFKey=pNext){
+
+    /* Remove the FK from the fkeyHash hash table. */
+    if( pFKey->pPrevTo ){
+      pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
+    }else{
+      void *data = (void *)pFKey->pNextTo;
+      const char *z = (data ? pFKey->pNextTo->zTo : pFKey->zTo);
+      sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), data);
+    }
+    if( pFKey->pNextTo ){
+      pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
+    }
+
+    /* Delete any triggers created to implement actions for this FK. */
+#ifndef SQLITE_OMIT_TRIGGER
+    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[0]);
+    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[1]);
+#endif
+
+    /* EV: R-30323-21917 Each foreign key constraint in SQLite is
+    ** classified as either immediate or deferred.
+    */
+    assert( pFKey->isDeferred==0 || pFKey->isDeferred==1 );
+
+    pNext = pFKey->pNextFrom;
+    sqlite3DbFree(pTab->dbMem, pFKey);
+  }
+}
+#endif /* ifndef SQLITE_OMIT_FOREIGN_KEY */
+
+/************** End of fkey.c ************************************************/
+/************** Begin file insert.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that are called by the parser
+** to handle INSERT statements in SQLite.
+**
+** $Id: insert.c,v 1.270 2009/07/24 17:58:53 danielk1977 Exp $
+*/
+
+/*
+** Generate code that will open a table for reading.
+*/
+SQLITE_PRIVATE void sqlite3OpenTable(
+  Parse *p,       /* Generate code into this VDBE */
+  int iCur,       /* The cursor number of the table */
+  int iDb,        /* The database index in sqlite3.aDb[] */
+  Table *pTab,    /* The table to be opened */
+  int opcode      /* OP_OpenRead or OP_OpenWrite */
+){
+  Vdbe *v;
+  if( IsVirtual(pTab) ) return;
+  v = sqlite3GetVdbe(p);
+  assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
+  sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName);
+  sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
+  sqlite3VdbeChangeP4(v, -1, SQLITE_INT_TO_PTR(pTab->nCol), P4_INT32);
+  VdbeComment((v, "%s", pTab->zName));
+}
+
+/*
+** Return a pointer to the column affinity string associated with index
+** pIdx. A column affinity string has one character for each column in 
+** the table, according to the affinity of the column:
+**
+**  Character      Column affinity
+**  ------------------------------
+**  'a'            TEXT
+**  'b'            NONE
+**  'c'            NUMERIC
+**  'd'            INTEGER
+**  'e'            REAL
+**
+** An extra 'b' is appended to the end of the string to cover the
+** rowid that appears as the last column in every index.
+**
+** Memory for the buffer containing the column index affinity string
+** is managed along with the rest of the Index structure. It will be
+** released when sqlite3DeleteIndex() is called.
+*/
+SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(Vdbe *v, Index *pIdx){
+  if( !pIdx->zColAff ){
+    /* The first time a column affinity string for a particular index is
+    ** required, it is allocated and populated here. It is then stored as
+    ** a member of the Index structure for subsequent use.
+    **
+    ** The column affinity string will eventually be deleted by
+    ** sqliteDeleteIndex() when the Index structure itself is cleaned
+    ** up.
+    */
+    int n;
+    Table *pTab = pIdx->pTable;
+    sqlite3 *db = sqlite3VdbeDb(v);
+    pIdx->zColAff = (char *)sqlite3Malloc(pIdx->nColumn+2);
+    if( !pIdx->zColAff ){
+      db->mallocFailed = 1;
+      return 0;
+    }
+    for(n=0; n<pIdx->nColumn; n++){
+      pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity;
+    }
+    pIdx->zColAff[n++] = SQLITE_AFF_NONE;
+    pIdx->zColAff[n] = 0;
+  }
+ 
+  return pIdx->zColAff;
+}
+
+/*
+** Set P4 of the most recently inserted opcode to a column affinity
+** string for table pTab. A column affinity string has one character
+** for each column indexed by the index, according to the affinity of the
+** column:
+**
+**  Character      Column affinity
+**  ------------------------------
+**  'a'            TEXT
+**  'b'            NONE
+**  'c'            NUMERIC
+**  'd'            INTEGER
+**  'e'            REAL
+*/
+SQLITE_PRIVATE void sqlite3TableAffinityStr(Vdbe *v, Table *pTab){
+  /* The first time a column affinity string for a particular table
+  ** is required, it is allocated and populated here. It is then 
+  ** stored as a member of the Table structure for subsequent use.
+  **
+  ** The column affinity string will eventually be deleted by
+  ** sqlite3DeleteTable() when the Table structure itself is cleaned up.
+  */
+  if( !pTab->zColAff ){
+    char *zColAff;
+    int i;
+    sqlite3 *db = sqlite3VdbeDb(v);
+
+    zColAff = (char *)sqlite3Malloc(pTab->nCol+1);
+    if( !zColAff ){
+      db->mallocFailed = 1;
+      return;
+    }
+
+    for(i=0; i<pTab->nCol; i++){
+      zColAff[i] = pTab->aCol[i].affinity;
+    }
+    zColAff[pTab->nCol] = '\0';
+
+    pTab->zColAff = zColAff;
+  }
+
+  sqlite3VdbeChangeP4(v, -1, pTab->zColAff, 0);
+}
+
+/*
+** Return non-zero if the table pTab in database iDb or any of its indices
+** have been opened at any point in the VDBE program beginning at location
+** iStartAddr throught the end of the program.  This is used to see if 
+** a statement of the form  "INSERT INTO <iDb, pTab> SELECT ..." can 
+** run without using temporary table for the results of the SELECT. 
+*/
+static int readsTable(Parse *p, int iStartAddr, int iDb, Table *pTab){
+  Vdbe *v = sqlite3GetVdbe(p);
+  int i;
+  int iEnd = sqlite3VdbeCurrentAddr(v);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  VTable *pVTab = IsVirtual(pTab) ? sqlite3GetVTable(p->db, pTab) : 0;
+#endif
+
+  for(i=iStartAddr; i<iEnd; i++){
+    VdbeOp *pOp = sqlite3VdbeGetOp(v, i);
+    assert( pOp!=0 );
+    if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){
+      Index *pIndex;
+      int tnum = pOp->p2;
+      if( tnum==pTab->tnum ){
+        return 1;
+      }
+      for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
+        if( tnum==pIndex->tnum ){
+          return 1;
+        }
+      }
+    }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pVTab ){
+      assert( pOp->p4.pVtab!=0 );
+      assert( pOp->p4type==P4_VTAB );
+      return 1;
+    }
+#endif
+  }
+  return 0;
+}
+
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+/*
+** Locate or create an AutoincInfo structure associated with table pTab
+** which is in database iDb.  Return the register number for the register
+** that holds the maximum rowid.
+**
+** There is at most one AutoincInfo structure per table even if the
+** same table is autoincremented multiple times due to inserts within
+** triggers.  A new AutoincInfo structure is created if this is the
+** first use of table pTab.  On 2nd and subsequent uses, the original
+** AutoincInfo structure is used.
+**
+** Three memory locations are allocated:
+**
+**   (1)  Register to hold the name of the pTab table.
+**   (2)  Register to hold the maximum ROWID of pTab.
+**   (3)  Register to hold the rowid in sqlite_sequence of pTab
+**
+** The 2nd register is the one that is returned.  That is all the
+** insert routine needs to know about.
+*/
+static int autoIncBegin(
+  Parse *pParse,      /* Parsing context */
+  int iDb,            /* Index of the database holding pTab */
+  Table *pTab         /* The table we are writing to */
+){
+  int memId = 0;      /* Register holding maximum rowid */
+  if( pTab->tabFlags & TF_Autoincrement ){
+    Parse *pToplevel = sqlite3ParseToplevel(pParse);
+    AutoincInfo *pInfo;
+
+    pInfo = pToplevel->pAinc;
+    while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; }
+    if( pInfo==0 ){
+      pInfo = sqlite3DbMallocRaw(pParse->db, sizeof(*pInfo));
+      if( pInfo==0 ) return 0;
+      pInfo->pNext = pToplevel->pAinc;
+      pToplevel->pAinc = pInfo;
+      pInfo->pTab = pTab;
+      pInfo->iDb = iDb;
+      pToplevel->nMem++;                  /* Register to hold name of table */
+      pInfo->regCtr = ++pToplevel->nMem;  /* Max rowid register */
+      pToplevel->nMem++;                  /* Rowid in sqlite_sequence */
+    }
+    memId = pInfo->regCtr;
+  }
+  return memId;
+}
+
+/*
+** This routine generates code that will initialize all of the
+** register used by the autoincrement tracker.  
+*/
+SQLITE_PRIVATE void sqlite3AutoincrementBegin(Parse *pParse){
+  AutoincInfo *p;            /* Information about an AUTOINCREMENT */
+  sqlite3 *db = pParse->db;  /* The database connection */
+  Db *pDb;                   /* Database only autoinc table */
+  int memId;                 /* Register holding max rowid */
+  int addr;                  /* A VDBE address */
+  Vdbe *v = pParse->pVdbe;   /* VDBE under construction */
+
+  /* This routine is never called during trigger-generation.  It is
+  ** only called from the top-level */
+  assert( pParse->pTriggerTab==0 );
+  assert( pParse==sqlite3ParseToplevel(pParse) );
+
+  assert( v );   /* We failed long ago if this is not so */
+  for(p = pParse->pAinc; p; p = p->pNext){
+    pDb = &db->aDb[p->iDb];
+    memId = p->regCtr;
+    sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
+    addr = sqlite3VdbeCurrentAddr(v);
+    sqlite3VdbeAddOp4(v, OP_String8, 0, memId-1, 0, p->pTab->zName, 0);
+    sqlite3VdbeAddOp2(v, OP_Rewind, 0, addr+9);
+    sqlite3VdbeAddOp3(v, OP_Column, 0, 0, memId);
+    sqlite3VdbeAddOp3(v, OP_Ne, memId-1, addr+7, memId);
+    sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
+    sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1);
+    sqlite3VdbeAddOp3(v, OP_Column, 0, 1, memId);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+9);
+    sqlite3VdbeAddOp2(v, OP_Next, 0, addr+2);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, memId);
+    sqlite3VdbeAddOp0(v, OP_Close);
+  }
+}
+
+/*
+** Update the maximum rowid for an autoincrement calculation.
+**
+** This routine should be called when the top of the stack holds a
+** new rowid that is about to be inserted.  If that new rowid is
+** larger than the maximum rowid in the memId memory cell, then the
+** memory cell is updated.  The stack is unchanged.
+*/
+static void autoIncStep(Parse *pParse, int memId, int regRowid){
+  if( memId>0 ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid);
+  }
+}
+
+/*
+** This routine generates the code needed to write autoincrement
+** maximum rowid values back into the sqlite_sequence register.
+** Every statement that might do an INSERT into an autoincrement
+** table (either directly or through triggers) needs to call this
+** routine just before the "exit" code.
+*/
+SQLITE_PRIVATE void sqlite3AutoincrementEnd(Parse *pParse){
+  AutoincInfo *p;
+  Vdbe *v = pParse->pVdbe;
+  sqlite3 *db = pParse->db;
+
+  assert( v );
+  for(p = pParse->pAinc; p; p = p->pNext){
+    Db *pDb = &db->aDb[p->iDb];
+    int j1, j2, j3, j4, j5;
+    int iRec;
+    int memId = p->regCtr;
+
+    iRec = sqlite3GetTempReg(pParse);
+    sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
+    j1 = sqlite3VdbeAddOp1(v, OP_NotNull, memId+1);
+    j2 = sqlite3VdbeAddOp0(v, OP_Rewind);
+    j3 = sqlite3VdbeAddOp3(v, OP_Column, 0, 0, iRec);
+    j4 = sqlite3VdbeAddOp3(v, OP_Eq, memId-1, 0, iRec);
+    sqlite3VdbeAddOp2(v, OP_Next, 0, j3);
+    sqlite3VdbeJumpHere(v, j2);
+    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, memId+1);
+    j5 = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, j4);
+    sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1);
+    sqlite3VdbeJumpHere(v, j1);
+    sqlite3VdbeJumpHere(v, j5);
+    sqlite3VdbeAddOp3(v, OP_MakeRecord, memId-1, 2, iRec);
+    sqlite3VdbeAddOp3(v, OP_Insert, 0, iRec, memId+1);
+    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+    sqlite3VdbeAddOp0(v, OP_Close);
+    sqlite3ReleaseTempReg(pParse, iRec);
+  }
+}
+#else
+/*
+** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines
+** above are all no-ops
+*/
+# define autoIncBegin(A,B,C) (0)
+# define autoIncStep(A,B,C)
+#endif /* SQLITE_OMIT_AUTOINCREMENT */
+
+
+/* Forward declaration */
+static int xferOptimization(
+  Parse *pParse,        /* Parser context */
+  Table *pDest,         /* The table we are inserting into */
+  Select *pSelect,      /* A SELECT statement to use as the data source */
+  int onError,          /* How to handle constraint errors */
+  int iDbDest           /* The database of pDest */
+);
+
+/*
+** This routine is call to handle SQL of the following forms:
+**
+**    insert into TABLE (IDLIST) values(EXPRLIST)
+**    insert into TABLE (IDLIST) select
+**
+** The IDLIST following the table name is always optional.  If omitted,
+** then a list of all columns for the table is substituted.  The IDLIST
+** appears in the pColumn parameter.  pColumn is NULL if IDLIST is omitted.
+**
+** The pList parameter holds EXPRLIST in the first form of the INSERT
+** statement above, and pSelect is NULL.  For the second form, pList is
+** NULL and pSelect is a pointer to the select statement used to generate
+** data for the insert.
+**
+** The code generated follows one of four templates.  For a simple
+** select with data coming from a VALUES clause, the code executes
+** once straight down through.  Pseudo-code follows (we call this
+** the "1st template"):
+**
+**         open write cursor to <table> and its indices
+**         puts VALUES clause expressions onto the stack
+**         write the resulting record into <table>
+**         cleanup
+**
+** The three remaining templates assume the statement is of the form
+**
+**   INSERT INTO <table> SELECT ...
+**
+** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" -
+** in other words if the SELECT pulls all columns from a single table
+** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and
+** if <table2> and <table1> are distinct tables but have identical
+** schemas, including all the same indices, then a special optimization
+** is invoked that copies raw records from <table2> over to <table1>.
+** See the xferOptimization() function for the implementation of this
+** template.  This is the 2nd template.
+**
+**         open a write cursor to <table>
+**         open read cursor on <table2>
+**         transfer all records in <table2> over to <table>
+**         close cursors
+**         foreach index on <table>
+**           open a write cursor on the <table> index
+**           open a read cursor on the corresponding <table2> index
+**           transfer all records from the read to the write cursors
+**           close cursors
+**         end foreach
+**
+** The 3rd template is for when the second template does not apply
+** and the SELECT clause does not read from <table> at any time.
+** The generated code follows this template:
+**
+**         EOF <- 0
+**         X <- A
+**         goto B
+**      A: setup for the SELECT
+**         loop over the rows in the SELECT
+**           load values into registers R..R+n
+**           yield X
+**         end loop
+**         cleanup after the SELECT
+**         EOF <- 1
+**         yield X
+**         goto A
+**      B: open write cursor to <table> and its indices
+**      C: yield X
+**         if EOF goto D
+**         insert the select result into <table> from R..R+n
+**         goto C
+**      D: cleanup
+**
+** The 4th template is used if the insert statement takes its
+** values from a SELECT but the data is being inserted into a table
+** that is also read as part of the SELECT.  In the third form,
+** we have to use a intermediate table to store the results of
+** the select.  The template is like this:
+**
+**         EOF <- 0
+**         X <- A
+**         goto B
+**      A: setup for the SELECT
+**         loop over the tables in the SELECT
+**           load value into register R..R+n
+**           yield X
+**         end loop
+**         cleanup after the SELECT
+**         EOF <- 1
+**         yield X
+**         halt-error
+**      B: open temp table
+**      L: yield X
+**         if EOF goto M
+**         insert row from R..R+n into temp table
+**         goto L
+**      M: open write cursor to <table> and its indices
+**         rewind temp table
+**      C: loop over rows of intermediate table
+**           transfer values form intermediate table into <table>
+**         end loop
+**      D: cleanup
+*/
+SQLITE_PRIVATE void sqlite3Insert(
+  Parse *pParse,        /* Parser context */
+  SrcList *pTabList,    /* Name of table into which we are inserting */
+  ExprList *pList,      /* List of values to be inserted */
+  Select *pSelect,      /* A SELECT statement to use as the data source */
+  IdList *pColumn,      /* Column names corresponding to IDLIST. */
+  int onError           /* How to handle constraint errors */
+){
+  sqlite3 *db;          /* The main database structure */
+  Table *pTab;          /* The table to insert into.  aka TABLE */
+  char *zTab;           /* Name of the table into which we are inserting */
+  const char *zDb;      /* Name of the database holding this table */
+  int i, j, idx;        /* Loop counters */
+  Vdbe *v;              /* Generate code into this virtual machine */
+  Index *pIdx;          /* For looping over indices of the table */
+  int nColumn;          /* Number of columns in the data */
+  int nHidden = 0;      /* Number of hidden columns if TABLE is virtual */
+  int baseCur = 0;      /* VDBE Cursor number for pTab */
+  int keyColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
+  int endOfLoop;        /* Label for the end of the insertion loop */
+  int useTempTable = 0; /* Store SELECT results in intermediate table */
+  int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
+  int addrInsTop = 0;   /* Jump to label "D" */
+  int addrCont = 0;     /* Top of insert loop. Label "C" in templates 3 and 4 */
+  int addrSelect = 0;   /* Address of coroutine that implements the SELECT */
+  SelectDest dest;      /* Destination for SELECT on rhs of INSERT */
+  int iDb;              /* Index of database holding TABLE */
+  Db *pDb;              /* The database containing table being inserted into */
+  int appendFlag = 0;   /* True if the insert is likely to be an append */
+
+  /* Register allocations */
+  int regFromSelect = 0;/* Base register for data coming from SELECT */
+  int regAutoinc = 0;   /* Register holding the AUTOINCREMENT counter */
+  int regRowCount = 0;  /* Memory cell used for the row counter */
+  int regIns;           /* Block of regs holding rowid+data being inserted */
+  int regRowid;         /* registers holding insert rowid */
+  int regData;          /* register holding first column to insert */
+  int regRecord;        /* Holds the assemblied row record */
+  int regEof = 0;       /* Register recording end of SELECT data */
+  int *aRegIdx = 0;     /* One register allocated to each index */
+
+#ifndef SQLITE_OMIT_TRIGGER
+  int isView;                 /* True if attempting to insert into a view */
+  Trigger *pTrigger;          /* List of triggers on pTab, if required */
+  int tmask;                  /* Mask of trigger times */
+#endif
+
+  db = pParse->db;
+  memset(&dest, 0, sizeof(dest));
+  if( pParse->nErr || db->mallocFailed ){
+    goto insert_cleanup;
+  }
+
+  /* Locate the table into which we will be inserting new information.
+  */
+  assert( pTabList->nSrc==1 );
+  zTab = pTabList->a[0].zName;
+  if( NEVER(zTab==0) ) goto insert_cleanup;
+  pTab = sqlite3SrcListLookup(pParse, pTabList);
+  if( pTab==0 ){
+    goto insert_cleanup;
+  }
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  assert( iDb<db->nDb );
+  pDb = &db->aDb[iDb];
+  zDb = pDb->zName;
+  if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
+    goto insert_cleanup;
+  }
+
+  /* Figure out if we have any triggers and if the table being
+  ** inserted into is a view
+  */
+#ifndef SQLITE_OMIT_TRIGGER
+  pTrigger = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask);
+  isView = pTab->pSelect!=0;
+#else
+# define pTrigger 0
+# define tmask 0
+# define isView 0
+#endif
+#ifdef SQLITE_OMIT_VIEW
+# undef isView
+# define isView 0
+#endif
+  assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) );
+
+  /* If pTab is really a view, make sure it has been initialized.
+  ** ViewGetColumnNames() is a no-op if pTab is not a view (or virtual 
+  ** module table).
+  */
+  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
+    goto insert_cleanup;
+  }
+
+  /* Ensure that:
+  *  (a) the table is not read-only, 
+  *  (b) that if it is a view then ON INSERT triggers exist
+  */
+  if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
+    goto insert_cleanup;
+  }
+
+  /* Allocate a VDBE
+  */
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ) goto insert_cleanup;
+  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
+  sqlite3BeginWriteOperation(pParse, pSelect || pTrigger, iDb);
+
+#ifndef SQLITE_OMIT_XFER_OPT
+  /* If the statement is of the form
+  **
+  **       INSERT INTO <table1> SELECT * FROM <table2>;
+  **
+  ** Then special optimizations can be applied that make the transfer
+  ** very fast and which reduce fragmentation of indices.
+  **
+  ** This is the 2nd template.
+  */
+  if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
+    assert( !pTrigger );
+    assert( pList==0 );
+    goto insert_end;
+  }
+#endif /* SQLITE_OMIT_XFER_OPT */
+
+  /* If this is an AUTOINCREMENT table, look up the sequence number in the
+  ** sqlite_sequence table and store it in memory cell regAutoinc.
+  */
+  regAutoinc = autoIncBegin(pParse, iDb, pTab);
+
+  /* Figure out how many columns of data are supplied.  If the data
+  ** is coming from a SELECT statement, then generate a co-routine that
+  ** produces a single row of the SELECT on each invocation.  The
+  ** co-routine is the common header to the 3rd and 4th templates.
+  */
+  if( pSelect ){
+    /* Data is coming from a SELECT.  Generate code to implement that SELECT
+    ** as a co-routine.  The code is common to both the 3rd and 4th
+    ** templates:
+    **
+    **         EOF <- 0
+    **         X <- A
+    **         goto B
+    **      A: setup for the SELECT
+    **         loop over the tables in the SELECT
+    **           load value into register R..R+n
+    **           yield X
+    **         end loop
+    **         cleanup after the SELECT
+    **         EOF <- 1
+    **         yield X
+    **         halt-error
+    **
+    ** On each invocation of the co-routine, it puts a single row of the
+    ** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1.
+    ** (These output registers are allocated by sqlite3Select().)  When
+    ** the SELECT completes, it sets the EOF flag stored in regEof.
+    */
+    int rc, j1;
+
+    regEof = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
+    VdbeComment((v, "SELECT eof flag"));
+    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
+    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
+    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm);
+    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
+    VdbeComment((v, "Jump over SELECT coroutine"));
+
+    /* Resolve the expressions in the SELECT statement and execute it. */
+    rc = sqlite3Select(pParse, pSelect, &dest);
+    assert( pParse->nErr==0 || rc );
+    if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
+      goto insert_cleanup;
+    }
+    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
+    sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);   /* yield X */
+    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
+    VdbeComment((v, "End of SELECT coroutine"));
+    sqlite3VdbeJumpHere(v, j1);                          /* label B: */
+
+    regFromSelect = dest.iMem;
+    assert( pSelect->pEList );
+    nColumn = pSelect->pEList->nExpr;
+    assert( dest.nMem==nColumn );
+
+    /* Set useTempTable to TRUE if the result of the SELECT statement
+    ** should be written into a temporary table (template 4).  Set to
+    ** FALSE if each* row of the SELECT can be written directly into
+    ** the destination table (template 3).
+    **
+    ** A temp table must be used if the table being updated is also one
+    ** of the tables being read by the SELECT statement.  Also use a 
+    ** temp table in the case of row triggers.
+    */
+    if( pTrigger || readsTable(pParse, addrSelect, iDb, pTab) ){
+      useTempTable = 1;
+    }
+
+    if( useTempTable ){
+      /* Invoke the coroutine to extract information from the SELECT
+      ** and add it to a transient table srcTab.  The code generated
+      ** here is from the 4th template:
+      **
+      **      B: open temp table
+      **      L: yield X
+      **         if EOF goto M
+      **         insert row from R..R+n into temp table
+      **         goto L
+      **      M: ...
+      */
+      int regRec;          /* Register to hold packed record */
+      int regTempRowid;    /* Register to hold temp table ROWID */
+      int addrTop;         /* Label "L" */
+      int addrIf;          /* Address of jump to M */
+
+      srcTab = pParse->nTab++;
+      regRec = sqlite3GetTempReg(pParse);
+      regTempRowid = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
+      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+      addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
+      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
+      sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
+      sqlite3VdbeJumpHere(v, addrIf);
+      sqlite3ReleaseTempReg(pParse, regRec);
+      sqlite3ReleaseTempReg(pParse, regTempRowid);
+    }
+  }else{
+    /* This is the case if the data for the INSERT is coming from a VALUES
+    ** clause
+    */
+    NameContext sNC;
+    memset(&sNC, 0, sizeof(sNC));
+    sNC.pParse = pParse;
+    srcTab = -1;
+    assert( useTempTable==0 );
+    nColumn = pList ? pList->nExpr : 0;
+    for(i=0; i<nColumn; i++){
+      if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){
+        goto insert_cleanup;
+      }
+    }
+  }
+
+  /* Make sure the number of columns in the source data matches the number
+  ** of columns to be inserted into the table.
+  */
+  if( IsVirtual(pTab) ){
+    for(i=0; i<pTab->nCol; i++){
+      nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0);
+    }
+  }
+  if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
+    sqlite3ErrorMsg(pParse, 
+       "table %S has %d columns but %d values were supplied",
+       pTabList, 0, pTab->nCol-nHidden, nColumn);
+    goto insert_cleanup;
+  }
+  if( pColumn!=0 && nColumn!=pColumn->nId ){
+    sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
+    goto insert_cleanup;
+  }
+
+  /* If the INSERT statement included an IDLIST term, then make sure
+  ** all elements of the IDLIST really are columns of the table and 
+  ** remember the column indices.
+  **
+  ** If the table has an INTEGER PRIMARY KEY column and that column
+  ** is named in the IDLIST, then record in the keyColumn variable
+  ** the index into IDLIST of the primary key column.  keyColumn is
+  ** the index of the primary key as it appears in IDLIST, not as
+  ** is appears in the original table.  (The index of the primary
+  ** key in the original table is pTab->iPKey.)
+  */
+  if( pColumn ){
+    for(i=0; i<pColumn->nId; i++){
+      pColumn->a[i].idx = -1;
+    }
+    for(i=0; i<pColumn->nId; i++){
+      for(j=0; j<pTab->nCol; j++){
+        if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
+          pColumn->a[i].idx = j;
+          if( j==pTab->iPKey ){
+            keyColumn = i;
+          }
+          break;
+        }
+      }
+      if( j>=pTab->nCol ){
+        if( sqlite3IsRowid(pColumn->a[i].zName) ){
+          keyColumn = i;
+        }else{
+          sqlite3ErrorMsg(pParse, "table %S has no column named %s",
+              pTabList, 0, pColumn->a[i].zName);
+          pParse->nErr++;
+          goto insert_cleanup;
+        }
+      }
+    }
+  }
+
+  /* If there is no IDLIST term but the table has an integer primary
+  ** key, the set the keyColumn variable to the primary key column index
+  ** in the original table definition.
+  */
+  if( pColumn==0 && nColumn>0 ){
+    keyColumn = pTab->iPKey;
+  }
+    
+  /* Initialize the count of rows to be inserted
+  */
+  if( db->flags & SQLITE_CountRows ){
+    regRowCount = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
+  }
+
+  /* If this is not a view, open the table and and all indices */
+  if( !isView ){
+    int nIdx;
+
+    baseCur = pParse->nTab;
+    nIdx = sqlite3OpenTableAndIndices(pParse, pTab, baseCur, OP_OpenWrite);
+    aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1));
+    if( aRegIdx==0 ){
+      goto insert_cleanup;
+    }
+    for(i=0; i<nIdx; i++){
+      aRegIdx[i] = ++pParse->nMem;
+    }
+  }
+
+  /* This is the top of the main insertion loop */
+  if( useTempTable ){
+    /* This block codes the top of loop only.  The complete loop is the
+    ** following pseudocode (template 4):
+    **
+    **         rewind temp table
+    **      C: loop over rows of intermediate table
+    **           transfer values form intermediate table into <table>
+    **         end loop
+    **      D: ...
+    */
+    addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab);
+    addrCont = sqlite3VdbeCurrentAddr(v);
+  }else if( pSelect ){
+    /* This block codes the top of loop only.  The complete loop is the
+    ** following pseudocode (template 3):
+    **
+    **      C: yield X
+    **         if EOF goto D
+    **         insert the select result into <table> from R..R+n
+    **         goto C
+    **      D: ...
+    */
+    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+    addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
+  }
+
+  /* Allocate registers for holding the rowid of the new row,
+  ** the content of the new row, and the assemblied row record.
+  */
+  regRecord = ++pParse->nMem;
+  regRowid = regIns = pParse->nMem+1;
+  pParse->nMem += pTab->nCol + 1;
+  if( IsVirtual(pTab) ){
+    regRowid++;
+    pParse->nMem++;
+  }
+  regData = regRowid+1;
+
+  /* Run the BEFORE and INSTEAD OF triggers, if there are any
+  */
+  endOfLoop = sqlite3VdbeMakeLabel(v);
+  if( tmask & TRIGGER_BEFORE ){
+    int regCols = sqlite3GetTempRange(pParse, pTab->nCol+1);
+
+    /* build the NEW.* reference row.  Note that if there is an INTEGER
+    ** PRIMARY KEY into which a NULL is being inserted, that NULL will be
+    ** translated into a unique ID for the row.  But on a BEFORE trigger,
+    ** we do not know what the unique ID will be (because the insert has
+    ** not happened yet) so we substitute a rowid of -1
+    */
+    if( keyColumn<0 ){
+      sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols);
+    }else{
+      int j1;
+      if( useTempTable ){
+        sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regCols);
+      }else{
+        assert( pSelect==0 );  /* Otherwise useTempTable is true */
+        sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regCols);
+      }
+      j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regCols);
+      sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols);
+      sqlite3VdbeJumpHere(v, j1);
+      sqlite3VdbeAddOp1(v, OP_MustBeInt, regCols);
+    }
+
+    /* Cannot have triggers on a virtual table. If it were possible,
+    ** this block would have to account for hidden column.
+    */
+    assert( !IsVirtual(pTab) );
+
+    /* Create the new column data
+    */
+    for(i=0; i<pTab->nCol; i++){
+      if( pColumn==0 ){
+        j = i;
+      }else{
+        for(j=0; j<pColumn->nId; j++){
+          if( pColumn->a[j].idx==i ) break;
+        }
+      }
+      if( pColumn && j>=pColumn->nId ){
+        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1);
+      }else if( useTempTable ){
+        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 
+      }else{
+        assert( pSelect==0 ); /* Otherwise useTempTable is true */
+        sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1);
+      }
+    }
+
+    /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
+    ** do not attempt any conversions before assembling the record.
+    ** If this is a real table, attempt conversions as required by the
+    ** table column affinities.
+    */
+    if( !isView ){
+      sqlite3VdbeAddOp2(v, OP_Affinity, regCols+1, pTab->nCol);
+      sqlite3TableAffinityStr(v, pTab);
+    }
+
+    /* Fire BEFORE or INSTEAD OF triggers */
+    sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 
+        pTab, regCols-pTab->nCol-1, onError, endOfLoop);
+
+    sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol+1);
+  }
+
+  /* Push the record number for the new entry onto the stack.  The
+  ** record number is a randomly generate integer created by NewRowid
+  ** except when the table has an INTEGER PRIMARY KEY column, in which
+  ** case the record number is the same as that column. 
+  */
+  if( !isView ){
+    if( IsVirtual(pTab) ){
+      /* The row that the VUpdate opcode will delete: none */
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regIns);
+    }
+    if( keyColumn>=0 ){
+      if( useTempTable ){
+        sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid);
+      }else if( pSelect ){
+        sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+keyColumn, regRowid);
+      }else{
+        VdbeOp *pOp;
+        sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regRowid);
+        pOp = sqlite3VdbeGetOp(v, -1);
+        if( ALWAYS(pOp) && pOp->opcode==OP_Null && !IsVirtual(pTab) ){
+          appendFlag = 1;
+          pOp->opcode = OP_NewRowid;
+          pOp->p1 = baseCur;
+          pOp->p2 = regRowid;
+          pOp->p3 = regAutoinc;
+        }
+      }
+      /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
+      ** to generate a unique primary key value.
+      */
+      if( !appendFlag ){
+        int j1;
+        if( !IsVirtual(pTab) ){
+          j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid);
+          sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
+          sqlite3VdbeJumpHere(v, j1);
+        }else{
+          j1 = sqlite3VdbeCurrentAddr(v);
+          sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, j1+2);
+        }
+        sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
+      }
+    }else if( IsVirtual(pTab) ){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid);
+    }else{
+      sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
+      appendFlag = 1;
+    }
+    autoIncStep(pParse, regAutoinc, regRowid);
+
+    /* Push onto the stack, data for all columns of the new entry, beginning
+    ** with the first column.
+    */
+    nHidden = 0;
+    for(i=0; i<pTab->nCol; i++){
+      int iRegStore = regRowid+1+i;
+      if( i==pTab->iPKey ){
+        /* The value of the INTEGER PRIMARY KEY column is always a NULL.
+        ** Whenever this column is read, the record number will be substituted
+        ** in its place.  So will fill this column with a NULL to avoid
+        ** taking up data space with information that will never be used. */
+        sqlite3VdbeAddOp2(v, OP_Null, 0, iRegStore);
+        continue;
+      }
+      if( pColumn==0 ){
+        if( IsHiddenColumn(&pTab->aCol[i]) ){
+          assert( IsVirtual(pTab) );
+          j = -1;
+          nHidden++;
+        }else{
+          j = i - nHidden;
+        }
+      }else{
+        for(j=0; j<pColumn->nId; j++){
+          if( pColumn->a[j].idx==i ) break;
+        }
+      }
+      if( j<0 || nColumn==0 || (pColumn && j>=pColumn->nId) ){
+        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, iRegStore);
+      }else if( useTempTable ){
+        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, iRegStore); 
+      }else if( pSelect ){
+        sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore);
+      }else{
+        sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore);
+      }
+    }
+
+    /* Generate code to check constraints and generate index keys and
+    ** do the insertion.
+    */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( IsVirtual(pTab) ){
+      const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
+      sqlite3VtabMakeWritable(pParse, pTab);
+      sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB);
+      sqlite3MayAbort(pParse);
+    }else
+#endif
+    {
+      int isReplace;    /* Set to true if constraints may cause a replace */
+      sqlite3GenerateConstraintChecks(pParse, pTab, baseCur, regIns, aRegIdx,
+          keyColumn>=0, 0, onError, endOfLoop, &isReplace
+      );
+      sqlite3FkCheck(pParse, pTab, 0, regIns);
+      sqlite3CompleteInsertion(
+          pParse, pTab, baseCur, regIns, aRegIdx, 0, appendFlag, isReplace==0
+      );
+    }
+  }
+
+  /* Update the count of rows that are inserted
+  */
+  if( (db->flags & SQLITE_CountRows)!=0 ){
+    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
+  }
+
+  if( pTrigger ){
+    /* Code AFTER triggers */
+    sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_AFTER, 
+        pTab, regData-2-pTab->nCol, onError, endOfLoop);
+  }
+
+  /* The bottom of the main insertion loop, if the data source
+  ** is a SELECT statement.
+  */
+  sqlite3VdbeResolveLabel(v, endOfLoop);
+  if( useTempTable ){
+    sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont);
+    sqlite3VdbeJumpHere(v, addrInsTop);
+    sqlite3VdbeAddOp1(v, OP_Close, srcTab);
+  }else if( pSelect ){
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrCont);
+    sqlite3VdbeJumpHere(v, addrInsTop);
+  }
+
+  if( !IsVirtual(pTab) && !isView ){
+    /* Close all tables opened */
+    sqlite3VdbeAddOp1(v, OP_Close, baseCur);
+    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
+      sqlite3VdbeAddOp1(v, OP_Close, idx+baseCur);
+    }
+  }
+
+insert_end:
+  /* Update the sqlite_sequence table by storing the content of the
+  ** maximum rowid counter values recorded while inserting into
+  ** autoincrement tables.
+  */
+  if( pParse->nested==0 && pParse->pTriggerTab==0 ){
+    sqlite3AutoincrementEnd(pParse);
+  }
+
+  /*
+  ** Return the number of rows inserted. If this routine is 
+  ** generating code because of a call to sqlite3NestedParse(), do not
+  ** invoke the callback function.
+  */
+  if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
+    sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", SQLITE_STATIC);
+  }
+
+insert_cleanup:
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprListDelete(db, pList);
+  sqlite3SelectDelete(db, pSelect);
+  sqlite3IdListDelete(db, pColumn);
+  sqlite3DbFree(db, aRegIdx);
+}
+
+/* Make sure "isView" and other macros defined above are undefined. Otherwise
+** thely may interfere with compilation of other functions in this file
+** (or in another file, if this file becomes part of the amalgamation).  */
+#ifdef isView
+ #undef isView
+#endif
+#ifdef pTrigger
+ #undef pTrigger
+#endif
+#ifdef tmask
+ #undef tmask
+#endif
+
+
+/*
+** Generate code to do constraint checks prior to an INSERT or an UPDATE.
+**
+** The input is a range of consecutive registers as follows:
+**
+**    1.  The rowid of the row after the update.
+**
+**    2.  The data in the first column of the entry after the update.
+**
+**    i.  Data from middle columns...
+**
+**    N.  The data in the last column of the entry after the update.
+**
+** The regRowid parameter is the index of the register containing (1).
+**
+** If isUpdate is true and rowidChng is non-zero, then rowidChng contains
+** the address of a register containing the rowid before the update takes
+** place. isUpdate is true for UPDATEs and false for INSERTs. If isUpdate
+** is false, indicating an INSERT statement, then a non-zero rowidChng 
+** indicates that the rowid was explicitly specified as part of the
+** INSERT statement. If rowidChng is false, it means that  the rowid is
+** computed automatically in an insert or that the rowid value is not 
+** modified by an update.
+**
+** The code generated by this routine store new index entries into
+** registers identified by aRegIdx[].  No index entry is created for
+** indices where aRegIdx[i]==0.  The order of indices in aRegIdx[] is
+** the same as the order of indices on the linked list of indices
+** attached to the table.
+**
+** This routine also generates code to check constraints.  NOT NULL,
+** CHECK, and UNIQUE constraints are all checked.  If a constraint fails,
+** then the appropriate action is performed.  There are five possible
+** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
+**
+**  Constraint type  Action       What Happens
+**  ---------------  ----------   ----------------------------------------
+**  any              ROLLBACK     The current transaction is rolled back and
+**                                sqlite3_exec() returns immediately with a
+**                                return code of SQLITE_CONSTRAINT.
+**
+**  any              ABORT        Back out changes from the current command
+**                                only (do not do a complete rollback) then
+**                                cause sqlite3_exec() to return immediately
+**                                with SQLITE_CONSTRAINT.
+**
+**  any              FAIL         Sqlite_exec() returns immediately with a
+**                                return code of SQLITE_CONSTRAINT.  The
+**                                transaction is not rolled back and any
+**                                prior changes are retained.
+**
+**  any              IGNORE       The record number and data is popped from
+**                                the stack and there is an immediate jump
+**                                to label ignoreDest.
+**
+**  NOT NULL         REPLACE      The NULL value is replace by the default
+**                                value for that column.  If the default value
+**                                is NULL, the action is the same as ABORT.
+**
+**  UNIQUE           REPLACE      The other row that conflicts with the row
+**                                being inserted is removed.
+**
+**  CHECK            REPLACE      Illegal.  The results in an exception.
+**
+** Which action to take is determined by the overrideError parameter.
+** Or if overrideError==OE_Default, then the pParse->onError parameter
+** is used.  Or if pParse->onError==OE_Default then the onError value
+** for the constraint is used.
+**
+** The calling routine must open a read/write cursor for pTab with
+** cursor number "baseCur".  All indices of pTab must also have open
+** read/write cursors with cursor number baseCur+i for the i-th cursor.
+** Except, if there is no possibility of a REPLACE action then
+** cursors do not need to be open for indices where aRegIdx[i]==0.
+*/
+SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
+  Parse *pParse,      /* The parser context */
+  Table *pTab,        /* the table into which we are inserting */
+  int baseCur,        /* Index of a read/write cursor pointing at pTab */
+  int regRowid,       /* Index of the range of input registers */
+  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
+  int rowidChng,      /* True if the rowid might collide with existing entry */
+  int isUpdate,       /* True for UPDATE, False for INSERT */
+  int overrideError,  /* Override onError to this if not OE_Default */
+  int ignoreDest,     /* Jump to this label on an OE_Ignore resolution */
+  int *pbMayReplace   /* OUT: Set to true if constraint may cause a replace */
+){
+  int i;              /* loop counter */
+  Vdbe *v;            /* VDBE under constrution */
+  int nCol;           /* Number of columns */
+  int onError;        /* Conflict resolution strategy */
+  int j1;             /* Addresss of jump instruction */
+  int j2 = 0, j3;     /* Addresses of jump instructions */
+  int regData;        /* Register containing first data column */
+  int iCur;           /* Table cursor number */
+  Index *pIdx;         /* Pointer to one of the indices */
+  int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */
+  int regOldRowid = (rowidChng && isUpdate) ? rowidChng : regRowid;
+
+  v = sqlite3GetVdbe(pParse);
+  assert( v!=0 );
+  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
+  nCol = pTab->nCol;
+  regData = regRowid + 1;
+
+  /* Test all NOT NULL constraints.
+  */
+  for(i=0; i<nCol; i++){
+    if( i==pTab->iPKey ){
+      continue;
+    }
+    onError = pTab->aCol[i].notNull;
+    if( onError==OE_None ) continue;
+    if( overrideError!=OE_Default ){
+      onError = overrideError;
+    }else if( onError==OE_Default ){
+      onError = OE_Abort;
+    }
+    if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
+      onError = OE_Abort;
+    }
+    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
+        || onError==OE_Ignore || onError==OE_Replace );
+    switch( onError ){
+      case OE_Abort:
+        sqlite3MayAbort(pParse);
+      case OE_Rollback:
+      case OE_Fail: {
+        char *zMsg;
+        j1 = sqlite3VdbeAddOp3(v, OP_HaltIfNull,
+                                  SQLITE_CONSTRAINT, onError, regData+i);
+        zMsg = sqlite3MPrintf(pParse->db, "%s.%s may not be NULL",
+                              pTab->zName, pTab->aCol[i].zName);
+        sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
+        break;
+      }
+      case OE_Ignore: {
+        sqlite3VdbeAddOp2(v, OP_IsNull, regData+i, ignoreDest);
+        break;
+      }
+      default: {
+        assert( onError==OE_Replace );
+        j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regData+i);
+        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regData+i);
+        sqlite3VdbeJumpHere(v, j1);
+        break;
+      }
+    }
+  }
+
+  /* Test all CHECK constraints
+  */
+#ifndef SQLITE_OMIT_CHECK
+  if( pTab->pCheck && (pParse->db->flags & SQLITE_IgnoreChecks)==0 ){
+    int allOk = sqlite3VdbeMakeLabel(v);
+    pParse->ckBase = regData;
+    sqlite3ExprIfTrue(pParse, pTab->pCheck, allOk, SQLITE_JUMPIFNULL);
+    onError = overrideError!=OE_Default ? overrideError : OE_Abort;
+    if( onError==OE_Ignore ){
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
+    }else{
+      sqlite3HaltConstraint(pParse, onError, 0, 0);
+    }
+    sqlite3VdbeResolveLabel(v, allOk);
+  }
+#endif /* !defined(SQLITE_OMIT_CHECK) */
+
+  /* If we have an INTEGER PRIMARY KEY, make sure the primary key
+  ** of the new record does not previously exist.  Except, if this
+  ** is an UPDATE and the primary key is not changing, that is OK.
+  */
+  if( rowidChng ){
+    onError = pTab->keyConf;
+    if( overrideError!=OE_Default ){
+      onError = overrideError;
+    }else if( onError==OE_Default ){
+      onError = OE_Abort;
+    }
+    
+    if( isUpdate ){
+      j2 = sqlite3VdbeAddOp3(v, OP_Eq, regRowid, 0, rowidChng);
+    }
+    j3 = sqlite3VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid);
+    switch( onError ){
+      default: {
+        onError = OE_Abort;
+        /* Fall thru into the next case */
+      }
+      case OE_Rollback:
+      case OE_Abort:
+      case OE_Fail: {
+        sqlite3HaltConstraint(
+          pParse, onError, "PRIMARY KEY must be unique", P4_STATIC);
+        break;
+      }
+      case OE_Replace: {
+        /* If there are DELETE triggers on this table and the
+        ** recursive-triggers flag is set, call GenerateRowDelete() to
+        ** remove the conflicting row from the the table. This will fire
+        ** the triggers and remove both the table and index b-tree entries.
+        **
+        ** Otherwise, if there are no triggers or the recursive-triggers
+        ** flag is not set, call GenerateRowIndexDelete(). This removes
+        ** the index b-tree entries only. The table b-tree entry will be 
+        ** replaced by the new entry when it is inserted.  */
+        Trigger *pTrigger = 0;
+        if( pParse->db->flags&SQLITE_RecTriggers ){
+          pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
+        }
+        sqlite3MultiWrite(pParse);
+        if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){
+          sqlite3GenerateRowDelete(
+              pParse, pTab, baseCur, regRowid, 0, pTrigger, OE_Replace
+          );
+        }else{
+          sqlite3GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
+        }
+        seenReplace = 1;
+        break;
+      }
+      case OE_Ignore: {
+        assert( seenReplace==0 );
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
+        break;
+      }
+    }
+    sqlite3VdbeJumpHere(v, j3);
+    if( isUpdate ){
+      sqlite3VdbeJumpHere(v, j2);
+    }
+  }
+
+  /* Test all UNIQUE constraints by creating entries for each UNIQUE
+  ** index and making sure that duplicate entries do not already exist.
+  ** Add the new records to the indices as we go.
+  */
+  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
+    int regIdx;
+    int regR;
+
+    if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */
+
+    /* Create a key for accessing the index entry */
+    regIdx = sqlite3GetTempRange(pParse, pIdx->nColumn+1);
+    for(i=0; i<pIdx->nColumn; i++){
+      int idx = pIdx->aiColumn[i];
+      if( idx==pTab->iPKey ){
+        sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_SCopy, regData+idx, regIdx+i);
+      }
+    }
+    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
+    sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]);
+    sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v, pIdx), 0);
+    sqlite3ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1);
+
+    /* Find out what action to take in case there is an indexing conflict */
+    onError = pIdx->onError;
+    if( onError==OE_None ){ 
+      sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
+      continue;  /* pIdx is not a UNIQUE index */
+    }
+    if( overrideError!=OE_Default ){
+      onError = overrideError;
+    }else if( onError==OE_Default ){
+      onError = OE_Abort;
+    }
+    if( seenReplace ){
+      if( onError==OE_Ignore ) onError = OE_Replace;
+      else if( onError==OE_Fail ) onError = OE_Abort;
+    }
+    
+    /* Check to see if the new index entry will be unique */
+    regR = sqlite3GetTempReg(pParse);
+    sqlite3VdbeAddOp2(v, OP_SCopy, regOldRowid, regR);
+    j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
+                           regR, SQLITE_INT_TO_PTR(regIdx),
+                           P4_INT32);
+    sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
+
+    /* Generate code that executes if the new index entry is not unique */
+    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
+        || onError==OE_Ignore || onError==OE_Replace );
+    switch( onError ){
+      case OE_Rollback:
+      case OE_Abort:
+      case OE_Fail: {
+        int j;
+        StrAccum errMsg;
+        const char *zSep;
+        char *zErr;
+
+        sqlite3StrAccumInit(&errMsg, 0, 0, 200);
+        errMsg.db = pParse->db;
+        zSep = pIdx->nColumn>1 ? "columns " : "column ";
+        for(j=0; j<pIdx->nColumn; j++){
+          char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
+          sqlite3StrAccumAppend(&errMsg, zSep, -1);
+          zSep = ", ";
+          sqlite3StrAccumAppend(&errMsg, zCol, -1);
+        }
+        sqlite3StrAccumAppend(&errMsg,
+            pIdx->nColumn>1 ? " are not unique" : " is not unique", -1);
+        zErr = sqlite3StrAccumFinish(&errMsg);
+        sqlite3HaltConstraint(pParse, onError, zErr, 0);
+        sqlite3DbFree(errMsg.db, zErr);
+        break;
+      }
+      case OE_Ignore: {
+        assert( seenReplace==0 );
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
+        break;
+      }
+      default: {
+        Trigger *pTrigger = 0;
+        assert( onError==OE_Replace );
+        sqlite3MultiWrite(pParse);
+        if( pParse->db->flags&SQLITE_RecTriggers ){
+          pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
+        }
+        sqlite3GenerateRowDelete(
+            pParse, pTab, baseCur, regR, 0, pTrigger, OE_Replace
+        );
+        seenReplace = 1;
+        break;
+      }
+    }
+    sqlite3VdbeJumpHere(v, j3);
+    sqlite3ReleaseTempReg(pParse, regR);
+  }
+  
+  if( pbMayReplace ){
+    *pbMayReplace = seenReplace;
+  }
+}
+
+/*
+** This routine generates code to finish the INSERT or UPDATE operation
+** that was started by a prior call to sqlite3GenerateConstraintChecks.
+** A consecutive range of registers starting at regRowid contains the
+** rowid and the content to be inserted.
+**
+** The arguments to this routine should be the same as the first six
+** arguments to sqlite3GenerateConstraintChecks.
+*/
+SQLITE_PRIVATE void sqlite3CompleteInsertion(
+  Parse *pParse,      /* The parser context */
+  Table *pTab,        /* the table into which we are inserting */
+  int baseCur,        /* Index of a read/write cursor pointing at pTab */
+  int regRowid,       /* Range of content */
+  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
+  int isUpdate,       /* True for UPDATE, False for INSERT */
+  int appendBias,     /* True if this is likely to be an append */
+  int useSeekResult   /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */
+){
+  int i;
+  Vdbe *v;
+  int nIdx;
+  Index *pIdx;
+  u8 pik_flags;
+  int regData;
+  int regRec;
+
+  v = sqlite3GetVdbe(pParse);
+  assert( v!=0 );
+  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
+  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
+  for(i=nIdx-1; i>=0; i--){
+    if( aRegIdx[i]==0 ) continue;
+    sqlite3VdbeAddOp2(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i]);
+    if( useSeekResult ){
+      sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
+    }
+  }
+  regData = regRowid + 1;
+  regRec = sqlite3GetTempReg(pParse);
+  sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
+  sqlite3TableAffinityStr(v, pTab);
+  sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol);
+  if( pParse->nested ){
+    pik_flags = 0;
+  }else{
+    pik_flags = OPFLAG_NCHANGE;
+    pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID);
+  }
+  if( appendBias ){
+    pik_flags |= OPFLAG_APPEND;
+  }
+  if( useSeekResult ){
+    pik_flags |= OPFLAG_USESEEKRESULT;
+  }
+  sqlite3VdbeAddOp3(v, OP_Insert, baseCur, regRec, regRowid);
+  if( !pParse->nested ){
+    sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
+  }
+  sqlite3VdbeChangeP5(v, pik_flags);
+}
+
+/*
+** Generate code that will open cursors for a table and for all
+** indices of that table.  The "baseCur" parameter is the cursor number used
+** for the table.  Indices are opened on subsequent cursors.
+**
+** Return the number of indices on the table.
+*/
+SQLITE_PRIVATE int sqlite3OpenTableAndIndices(
+  Parse *pParse,   /* Parsing context */
+  Table *pTab,     /* Table to be opened */
+  int baseCur,     /* Cursor number assigned to the table */
+  int op           /* OP_OpenRead or OP_OpenWrite */
+){
+  int i;
+  int iDb;
+  Index *pIdx;
+  Vdbe *v;
+
+  if( IsVirtual(pTab) ) return 0;
+  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+  v = sqlite3GetVdbe(pParse);
+  assert( v!=0 );
+  sqlite3OpenTable(pParse, baseCur, iDb, pTab, op);
+  for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
+    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
+    assert( pIdx->pSchema==pTab->pSchema );
+    sqlite3VdbeAddOp4(v, op, i+baseCur, pIdx->tnum, iDb,
+                      (char*)pKey, P4_KEYINFO_HANDOFF);
+    VdbeComment((v, "%s", pIdx->zName));
+  }
+  if( pParse->nTab<baseCur+i ){
+    pParse->nTab = baseCur+i;
+  }
+  return i-1;
+}
+
+
+#ifdef SQLITE_TEST
+/*
+** The following global variable is incremented whenever the
+** transfer optimization is used.  This is used for testing
+** purposes only - to make sure the transfer optimization really
+** is happening when it is suppose to.
+*/
+SQLITE_API int sqlite3_xferopt_count;
+#endif /* SQLITE_TEST */
+
+
+#ifndef SQLITE_OMIT_XFER_OPT
+/*
+** Check to collation names to see if they are compatible.
+*/
+static int xferCompatibleCollation(const char *z1, const char *z2){
+  if( z1==0 ){
+    return z2==0;
+  }
+  if( z2==0 ){
+    return 0;
+  }
+  return sqlite3StrICmp(z1, z2)==0;
+}
+
+
+/*
+** Check to see if index pSrc is compatible as a source of data
+** for index pDest in an insert transfer optimization.  The rules
+** for a compatible index:
+**
+**    *   The index is over the same set of columns
+**    *   The same DESC and ASC markings occurs on all columns
+**    *   The same onError processing (OE_Abort, OE_Ignore, etc)
+**    *   The same collating sequence on each column
+*/
+static int xferCompatibleIndex(Index *pDest, Index *pSrc){
+  int i;
+  assert( pDest && pSrc );
+  assert( pDest->pTable!=pSrc->pTable );
+  if( pDest->nColumn!=pSrc->nColumn ){
+    return 0;   /* Different number of columns */
+  }
+  if( pDest->onError!=pSrc->onError ){
+    return 0;   /* Different conflict resolution strategies */
+  }
+  for(i=0; i<pSrc->nColumn; i++){
+    if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){
+      return 0;   /* Different columns indexed */
+    }
+    if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){
+      return 0;   /* Different sort orders */
+    }
+    if( !xferCompatibleCollation(pSrc->azColl[i],pDest->azColl[i]) ){
+      return 0;   /* Different collating sequences */
+    }
+  }
+
+  /* If no test above fails then the indices must be compatible */
+  return 1;
+}
+
+/*
+** Attempt the transfer optimization on INSERTs of the form
+**
+**     INSERT INTO tab1 SELECT * FROM tab2;
+**
+** This optimization is only attempted if
+**
+**    (1)  tab1 and tab2 have identical schemas including all the
+**         same indices and constraints
+**
+**    (2)  tab1 and tab2 are different tables
+**
+**    (3)  There must be no triggers on tab1
+**
+**    (4)  The result set of the SELECT statement is "*"
+**
+**    (5)  The SELECT statement has no WHERE, HAVING, ORDER BY, GROUP BY,
+**         or LIMIT clause.
+**
+**    (6)  The SELECT statement is a simple (not a compound) select that
+**         contains only tab2 in its FROM clause
+**
+** This method for implementing the INSERT transfers raw records from
+** tab2 over to tab1.  The columns are not decoded.  Raw records from
+** the indices of tab2 are transfered to tab1 as well.  In so doing,
+** the resulting tab1 has much less fragmentation.
+**
+** This routine returns TRUE if the optimization is attempted.  If any
+** of the conditions above fail so that the optimization should not
+** be attempted, then this routine returns FALSE.
+*/
+static int xferOptimization(
+  Parse *pParse,        /* Parser context */
+  Table *pDest,         /* The table we are inserting into */
+  Select *pSelect,      /* A SELECT statement to use as the data source */
+  int onError,          /* How to handle constraint errors */
+  int iDbDest           /* The database of pDest */
+){
+  ExprList *pEList;                /* The result set of the SELECT */
+  Table *pSrc;                     /* The table in the FROM clause of SELECT */
+  Index *pSrcIdx, *pDestIdx;       /* Source and destination indices */
+  struct SrcList_item *pItem;      /* An element of pSelect->pSrc */
+  int i;                           /* Loop counter */
+  int iDbSrc;                      /* The database of pSrc */
+  int iSrc, iDest;                 /* Cursors from source and destination */
+  int addr1, addr2;                /* Loop addresses */
+  int emptyDestTest;               /* Address of test for empty pDest */
+  int emptySrcTest;                /* Address of test for empty pSrc */
+  Vdbe *v;                         /* The VDBE we are building */
+  KeyInfo *pKey;                   /* Key information for an index */
+  int regAutoinc;                  /* Memory register used by AUTOINC */
+  int destHasUniqueIdx = 0;        /* True if pDest has a UNIQUE index */
+  int regData, regRowid;           /* Registers holding data and rowid */
+
+  if( pSelect==0 ){
+    return 0;   /* Must be of the form  INSERT INTO ... SELECT ... */
+  }
+  if( sqlite3TriggerList(pParse, pDest) ){
+    return 0;   /* tab1 must not have triggers */
+  }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( pDest->tabFlags & TF_Virtual ){
+    return 0;   /* tab1 must not be a virtual table */
+  }
+#endif
+  if( onError==OE_Default ){
+    onError = OE_Abort;
+  }
+  if( onError!=OE_Abort && onError!=OE_Rollback ){
+    return 0;   /* Cannot do OR REPLACE or OR IGNORE or OR FAIL */
+  }
+  assert(pSelect->pSrc);   /* allocated even if there is no FROM clause */
+  if( pSelect->pSrc->nSrc!=1 ){
+    return 0;   /* FROM clause must have exactly one term */
+  }
+  if( pSelect->pSrc->a[0].pSelect ){
+    return 0;   /* FROM clause cannot contain a subquery */
+  }
+  if( pSelect->pWhere ){
+    return 0;   /* SELECT may not have a WHERE clause */
+  }
+  if( pSelect->pOrderBy ){
+    return 0;   /* SELECT may not have an ORDER BY clause */
+  }
+  /* Do not need to test for a HAVING clause.  If HAVING is present but
+  ** there is no ORDER BY, we will get an error. */
+  if( pSelect->pGroupBy ){
+    return 0;   /* SELECT may not have a GROUP BY clause */
+  }
+  if( pSelect->pLimit ){
+    return 0;   /* SELECT may not have a LIMIT clause */
+  }
+  assert( pSelect->pOffset==0 );  /* Must be so if pLimit==0 */
+  if( pSelect->pPrior ){
+    return 0;   /* SELECT may not be a compound query */
+  }
+  if( pSelect->selFlags & SF_Distinct ){
+    return 0;   /* SELECT may not be DISTINCT */
+  }
+  pEList = pSelect->pEList;
+  assert( pEList!=0 );
+  if( pEList->nExpr!=1 ){
+    return 0;   /* The result set must have exactly one column */
+  }
+  assert( pEList->a[0].pExpr );
+  if( pEList->a[0].pExpr->op!=TK_ALL ){
+    return 0;   /* The result set must be the special operator "*" */
+  }
+
+  /* At this point we have established that the statement is of the
+  ** correct syntactic form to participate in this optimization.  Now
+  ** we have to check the semantics.
+  */
+  pItem = pSelect->pSrc->a;
+  pSrc = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+  if( pSrc==0 ){
+    return 0;   /* FROM clause does not contain a real table */
+  }
+  if( pSrc==pDest ){
+    return 0;   /* tab1 and tab2 may not be the same table */
+  }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( pSrc->tabFlags & TF_Virtual ){
+    return 0;   /* tab2 must not be a virtual table */
+  }
+#endif
+  if( pSrc->pSelect ){
+    return 0;   /* tab2 may not be a view */
+  }
+  if( pDest->nCol!=pSrc->nCol ){
+    return 0;   /* Number of columns must be the same in tab1 and tab2 */
+  }
+  if( pDest->iPKey!=pSrc->iPKey ){
+    return 0;   /* Both tables must have the same INTEGER PRIMARY KEY */
+  }
+  for(i=0; i<pDest->nCol; i++){
+    if( pDest->aCol[i].affinity!=pSrc->aCol[i].affinity ){
+      return 0;    /* Affinity must be the same on all columns */
+    }
+    if( !xferCompatibleCollation(pDest->aCol[i].zColl, pSrc->aCol[i].zColl) ){
+      return 0;    /* Collating sequence must be the same on all columns */
+    }
+    if( pDest->aCol[i].notNull && !pSrc->aCol[i].notNull ){
+      return 0;    /* tab2 must be NOT NULL if tab1 is */
+    }
+  }
+  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
+    if( pDestIdx->onError!=OE_None ){
+      destHasUniqueIdx = 1;
+    }
+    for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
+      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
+    }
+    if( pSrcIdx==0 ){
+      return 0;    /* pDestIdx has no corresponding index in pSrc */
+    }
+  }
+#ifndef SQLITE_OMIT_CHECK
+  if( pDest->pCheck && !sqlite3ExprCompare(pSrc->pCheck, pDest->pCheck) ){
+    return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
+  }
+#endif
+
+  /* If we get this far, it means either:
+  **
+  **    *   We can always do the transfer if the table contains an
+  **        an integer primary key
+  **
+  **    *   We can conditionally do the transfer if the destination
+  **        table is empty.
+  */
+#ifdef SQLITE_TEST
+  sqlite3_xferopt_count++;
+#endif
+  iDbSrc = sqlite3SchemaToIndex(pParse->db, pSrc->pSchema);
+  v = sqlite3GetVdbe(pParse);
+  sqlite3CodeVerifySchema(pParse, iDbSrc);
+  iSrc = pParse->nTab++;
+  iDest = pParse->nTab++;
+  regAutoinc = autoIncBegin(pParse, iDbDest, pDest);
+  sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite);
+  if( (pDest->iPKey<0 && pDest->pIndex!=0) || destHasUniqueIdx ){
+    /* If tables do not have an INTEGER PRIMARY KEY and there
+    ** are indices to be copied and the destination is not empty,
+    ** we have to disallow the transfer optimization because the
+    ** the rowids might change which will mess up indexing.
+    **
+    ** Or if the destination has a UNIQUE index and is not empty,
+    ** we also disallow the transfer optimization because we cannot
+    ** insure that all entries in the union of DEST and SRC will be
+    ** unique.
+    */
+    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0);
+    emptyDestTest = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
+    sqlite3VdbeJumpHere(v, addr1);
+  }else{
+    emptyDestTest = 0;
+  }
+  sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead);
+  emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
+  regData = sqlite3GetTempReg(pParse);
+  regRowid = sqlite3GetTempReg(pParse);
+  if( pDest->iPKey>=0 ){
+    addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
+    addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid);
+    sqlite3HaltConstraint(
+        pParse, onError, "PRIMARY KEY must be unique", P4_STATIC);
+    sqlite3VdbeJumpHere(v, addr2);
+    autoIncStep(pParse, regAutoinc, regRowid);
+  }else if( pDest->pIndex==0 ){
+    addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid);
+  }else{
+    addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
+    assert( (pDest->tabFlags & TF_Autoincrement)==0 );
+  }
+  sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData);
+  sqlite3VdbeAddOp3(v, OP_Insert, iDest, regData, regRowid);
+  sqlite3VdbeChangeP5(v, OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND);
+  sqlite3VdbeChangeP4(v, -1, pDest->zName, 0);
+  sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1);
+  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
+    for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){
+      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
+    }
+    assert( pSrcIdx );
+    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
+    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
+    pKey = sqlite3IndexKeyinfo(pParse, pSrcIdx);
+    sqlite3VdbeAddOp4(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc,
+                      (char*)pKey, P4_KEYINFO_HANDOFF);
+    VdbeComment((v, "%s", pSrcIdx->zName));
+    pKey = sqlite3IndexKeyinfo(pParse, pDestIdx);
+    sqlite3VdbeAddOp4(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest,
+                      (char*)pKey, P4_KEYINFO_HANDOFF);
+    VdbeComment((v, "%s", pDestIdx->zName));
+    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
+    sqlite3VdbeAddOp2(v, OP_RowKey, iSrc, regData);
+    sqlite3VdbeAddOp3(v, OP_IdxInsert, iDest, regData, 1);
+    sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1);
+    sqlite3VdbeJumpHere(v, addr1);
+  }
+  sqlite3VdbeJumpHere(v, emptySrcTest);
+  sqlite3ReleaseTempReg(pParse, regRowid);
+  sqlite3ReleaseTempReg(pParse, regData);
+  sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
+  sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
+  if( emptyDestTest ){
+    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0);
+    sqlite3VdbeJumpHere(v, emptyDestTest);
+    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
+    return 0;
+  }else{
+    return 1;
+  }
+}
+#endif /* SQLITE_OMIT_XFER_OPT */
+
+/************** End of insert.c **********************************************/
+/************** Begin file legacy.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Main file for the SQLite library.  The routines in this file
+** implement the programmer interface to the library.  Routines in
+** other files are for internal use by SQLite and should not be
+** accessed by users of the library.
+**
+** $Id: legacy.c,v 1.35 2009/08/07 16:56:00 danielk1977 Exp $
+*/
+
+
+/*
+** Execute SQL code.  Return one of the SQLITE_ success/failure
+** codes.  Also write an error message into memory obtained from
+** malloc() and make *pzErrMsg point to that message.
+**
+** If the SQL is a query, then for each row in the query result
+** the xCallback() function is called.  pArg becomes the first
+** argument to xCallback().  If xCallback=NULL then no callback
+** is invoked, even for queries.
+*/
+SQLITE_API int sqlite3_exec(
+  sqlite3 *db,                /* The database on which the SQL executes */
+  const char *zSql,           /* The SQL to be executed */
+  sqlite3_callback xCallback, /* Invoke this callback routine */
+  void *pArg,                 /* First argument to xCallback() */
+  char **pzErrMsg             /* Write error messages here */
+){
+  int rc = SQLITE_OK;         /* Return code */
+  const char *zLeftover;      /* Tail of unprocessed SQL */
+  sqlite3_stmt *pStmt = 0;    /* The current SQL statement */
+  char **azCols = 0;          /* Names of result columns */
+  int nRetry = 0;             /* Number of retry attempts */
+  int callbackIsInit;         /* True if callback data is initialized */
+
+  if( zSql==0 ) zSql = "";
+
+  sqlite3_mutex_enter(db->mutex);
+  sqlite3Error(db, SQLITE_OK, 0);
+  while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
+    int nCol;
+    char **azVals = 0;
+
+    pStmt = 0;
+    rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
+    assert( rc==SQLITE_OK || pStmt==0 );
+    if( rc!=SQLITE_OK ){
+      continue;
+    }
+    if( !pStmt ){
+      /* this happens for a comment or white-space */
+      zSql = zLeftover;
+      continue;
+    }
+
+    callbackIsInit = 0;
+    nCol = sqlite3_column_count(pStmt);
+
+    while( 1 ){
+      int i;
+      rc = sqlite3_step(pStmt);
+
+      /* Invoke the callback function if required */
+      if( xCallback && (SQLITE_ROW==rc || 
+          (SQLITE_DONE==rc && !callbackIsInit
+                           && db->flags&SQLITE_NullCallback)) ){
+        if( !callbackIsInit ){
+          azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1);
+          if( azCols==0 ){
+            goto exec_out;
+          }
+          for(i=0; i<nCol; i++){
+            azCols[i] = (char *)sqlite3_column_name(pStmt, i);
+            /* sqlite3VdbeSetColName() installs column names as UTF8
+            ** strings so there is no way for sqlite3_column_name() to fail. */
+            assert( azCols[i]!=0 );
+          }
+          callbackIsInit = 1;
+        }
+        if( rc==SQLITE_ROW ){
+          azVals = &azCols[nCol];
+          for(i=0; i<nCol; i++){
+            azVals[i] = (char *)sqlite3_column_text(pStmt, i);
+            if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){
+              db->mallocFailed = 1;
+              goto exec_out;
+            }
+          }
+        }
+        if( xCallback(pArg, nCol, azVals, azCols) ){
+          rc = SQLITE_ABORT;
+          sqlite3VdbeFinalize((Vdbe *)pStmt);
+          pStmt = 0;
+          sqlite3Error(db, SQLITE_ABORT, 0);
+          goto exec_out;
+        }
+      }
+
+      if( rc!=SQLITE_ROW ){
+        rc = sqlite3VdbeFinalize((Vdbe *)pStmt);
+        pStmt = 0;
+        if( rc!=SQLITE_SCHEMA ){
+          nRetry = 0;
+          zSql = zLeftover;
+          while( sqlite3Isspace(zSql[0]) ) zSql++;
+        }
+        break;
+      }
+    }
+
+    sqlite3DbFree(db, azCols);
+    azCols = 0;
+  }
+
+exec_out:
+  if( pStmt ) sqlite3VdbeFinalize((Vdbe *)pStmt);
+  sqlite3DbFree(db, azCols);
+
+  rc = sqlite3ApiExit(db, rc);
+  if( rc!=SQLITE_OK && ALWAYS(rc==sqlite3_errcode(db)) && pzErrMsg ){
+    int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db));
+    *pzErrMsg = sqlite3Malloc(nErrMsg);
+    if( *pzErrMsg ){
+      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
+    }else{
+      rc = SQLITE_NOMEM;
+      sqlite3Error(db, SQLITE_NOMEM, 0);
+    }
+  }else if( pzErrMsg ){
+    *pzErrMsg = 0;
+  }
+
+  assert( (rc&db->errMask)==rc );
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/************** End of legacy.c **********************************************/
+/************** Begin file loadext.c *****************************************/
+/*
+** 2006 June 7
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used to dynamically load extensions into
+** the SQLite library.
+**
+** $Id: loadext.c,v 1.60 2009/06/03 01:24:54 drh Exp $
+*/
+
+#ifndef SQLITE_CORE
+  #define SQLITE_CORE 1  /* Disable the API redefinition in sqlite3ext.h */
+#endif
+/************** Include sqlite3ext.h in the middle of loadext.c **************/
+/************** Begin file sqlite3ext.h **************************************/
+/*
+** 2006 June 7
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the SQLite interface for use by
+** shared libraries that want to be imported as extensions into
+** an SQLite instance.  Shared libraries that intend to be loaded
+** as extensions by SQLite should #include this file instead of 
+** sqlite3.h.
+**
+** @(#) $Id: sqlite3ext.h,v 1.25 2008/10/12 00:27:54 shane Exp $
+*/
+#ifndef _SQLITE3EXT_H_
+#define _SQLITE3EXT_H_
+
+typedef struct sqlite3_api_routines sqlite3_api_routines;
+
+/*
+** The following structure holds pointers to all of the SQLite API
+** routines.
+**
+** WARNING:  In order to maintain backwards compatibility, add new
+** interfaces to the end of this structure only.  If you insert new
+** interfaces in the middle of this structure, then older different
+** versions of SQLite will not be able to load each others' shared
+** libraries!
+*/
+struct sqlite3_api_routines {
+  void * (*aggregate_context)(sqlite3_context*,int nBytes);
+  int  (*aggregate_count)(sqlite3_context*);
+  int  (*bind_blob)(sqlite3_stmt*,int,const void*,int n,void(*)(void*));
+  int  (*bind_double)(sqlite3_stmt*,int,double);
+  int  (*bind_int)(sqlite3_stmt*,int,int);
+  int  (*bind_int64)(sqlite3_stmt*,int,sqlite_int64);
+  int  (*bind_null)(sqlite3_stmt*,int);
+  int  (*bind_parameter_count)(sqlite3_stmt*);
+  int  (*bind_parameter_index)(sqlite3_stmt*,const char*zName);
+  const char * (*bind_parameter_name)(sqlite3_stmt*,int);
+  int  (*bind_text)(sqlite3_stmt*,int,const char*,int n,void(*)(void*));
+  int  (*bind_text16)(sqlite3_stmt*,int,const void*,int,void(*)(void*));
+  int  (*bind_value)(sqlite3_stmt*,int,const sqlite3_value*);
+  int  (*busy_handler)(sqlite3*,int(*)(void*,int),void*);
+  int  (*busy_timeout)(sqlite3*,int ms);
+  int  (*changes)(sqlite3*);
+  int  (*close)(sqlite3*);
+  int  (*collation_needed)(sqlite3*,void*,void(*)(void*,sqlite3*,int eTextRep,const char*));
+  int  (*collation_needed16)(sqlite3*,void*,void(*)(void*,sqlite3*,int eTextRep,const void*));
+  const void * (*column_blob)(sqlite3_stmt*,int iCol);
+  int  (*column_bytes)(sqlite3_stmt*,int iCol);
+  int  (*column_bytes16)(sqlite3_stmt*,int iCol);
+  int  (*column_count)(sqlite3_stmt*pStmt);
+  const char * (*column_database_name)(sqlite3_stmt*,int);
+  const void * (*column_database_name16)(sqlite3_stmt*,int);
+  const char * (*column_decltype)(sqlite3_stmt*,int i);
+  const void * (*column_decltype16)(sqlite3_stmt*,int);
+  double  (*column_double)(sqlite3_stmt*,int iCol);
+  int  (*column_int)(sqlite3_stmt*,int iCol);
+  sqlite_int64  (*column_int64)(sqlite3_stmt*,int iCol);
+  const char * (*column_name)(sqlite3_stmt*,int);
+  const void * (*column_name16)(sqlite3_stmt*,int);
+  const char * (*column_origin_name)(sqlite3_stmt*,int);
+  const void * (*column_origin_name16)(sqlite3_stmt*,int);
+  const char * (*column_table_name)(sqlite3_stmt*,int);
+  const void * (*column_table_name16)(sqlite3_stmt*,int);
+  const unsigned char * (*column_text)(sqlite3_stmt*,int iCol);
+  const void * (*column_text16)(sqlite3_stmt*,int iCol);
+  int  (*column_type)(sqlite3_stmt*,int iCol);
+  sqlite3_value* (*column_value)(sqlite3_stmt*,int iCol);
+  void * (*commit_hook)(sqlite3*,int(*)(void*),void*);
+  int  (*complete)(const char*sql);
+  int  (*complete16)(const void*sql);
+  int  (*create_collation)(sqlite3*,const char*,int,void*,int(*)(void*,int,const void*,int,const void*));
+  int  (*create_collation16)(sqlite3*,const void*,int,void*,int(*)(void*,int,const void*,int,const void*));
+  int  (*create_function)(sqlite3*,const char*,int,int,void*,void (*xFunc)(sqlite3_context*,int,sqlite3_value**),void (*xStep)(sqlite3_context*,int,sqlite3_value**),void (*xFinal)(sqlite3_context*));
+  int  (*create_function16)(sqlite3*,const void*,int,int,void*,void (*xFunc)(sqlite3_context*,int,sqlite3_value**),void (*xStep)(sqlite3_context*,int,sqlite3_value**),void (*xFinal)(sqlite3_context*));
+  int (*create_module)(sqlite3*,const char*,const sqlite3_module*,void*);
+  int  (*data_count)(sqlite3_stmt*pStmt);
+  sqlite3 * (*db_handle)(sqlite3_stmt*);
+  int (*declare_vtab)(sqlite3*,const char*);
+  int  (*enable_shared_cache)(int);
+  int  (*errcode)(sqlite3*db);
+  const char * (*errmsg)(sqlite3*);
+  const void * (*errmsg16)(sqlite3*);
+  int  (*exec)(sqlite3*,const char*,sqlite3_callback,void*,char**);
+  int  (*expired)(sqlite3_stmt*);
+  int  (*finalize)(sqlite3_stmt*pStmt);
+  void  (*free)(void*);
+  void  (*free_table)(char**result);
+  int  (*get_autocommit)(sqlite3*);
+  void * (*get_auxdata)(sqlite3_context*,int);
+  int  (*get_table)(sqlite3*,const char*,char***,int*,int*,char**);
+  int  (*global_recover)(void);
+  void  (*interruptx)(sqlite3*);
+  sqlite_int64  (*last_insert_rowid)(sqlite3*);
+  const char * (*libversion)(void);
+  int  (*libversion_number)(void);
+  void *(*malloc)(int);
+  char * (*mprintf)(const char*,...);
+  int  (*open)(const char*,sqlite3**);
+  int  (*open16)(const void*,sqlite3**);
+  int  (*prepare)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
+  int  (*prepare16)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
+  void * (*profile)(sqlite3*,void(*)(void*,const char*,sqlite_uint64),void*);
+  void  (*progress_handler)(sqlite3*,int,int(*)(void*),void*);
+  void *(*realloc)(void*,int);
+  int  (*reset)(sqlite3_stmt*pStmt);
+  void  (*result_blob)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_double)(sqlite3_context*,double);
+  void  (*result_error)(sqlite3_context*,const char*,int);
+  void  (*result_error16)(sqlite3_context*,const void*,int);
+  void  (*result_int)(sqlite3_context*,int);
+  void  (*result_int64)(sqlite3_context*,sqlite_int64);
+  void  (*result_null)(sqlite3_context*);
+  void  (*result_text)(sqlite3_context*,const char*,int,void(*)(void*));
+  void  (*result_text16)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_text16be)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_text16le)(sqlite3_context*,const void*,int,void(*)(void*));
+  void  (*result_value)(sqlite3_context*,sqlite3_value*);
+  void * (*rollback_hook)(sqlite3*,void(*)(void*),void*);
+  int  (*set_authorizer)(sqlite3*,int(*)(void*,int,const char*,const char*,const char*,const char*),void*);
+  void  (*set_auxdata)(sqlite3_context*,int,void*,void (*)(void*));
+  char * (*snprintf)(int,char*,const char*,...);
+  int  (*step)(sqlite3_stmt*);
+  int  (*table_column_metadata)(sqlite3*,const char*,const char*,const char*,char const**,char const**,int*,int*,int*);
+  void  (*thread_cleanup)(void);
+  int  (*total_changes)(sqlite3*);
+  void * (*trace)(sqlite3*,void(*xTrace)(void*,const char*),void*);
+  int  (*transfer_bindings)(sqlite3_stmt*,sqlite3_stmt*);
+  void * (*update_hook)(sqlite3*,void(*)(void*,int ,char const*,char const*,sqlite_int64),void*);
+  void * (*user_data)(sqlite3_context*);
+  const void * (*value_blob)(sqlite3_value*);
+  int  (*value_bytes)(sqlite3_value*);
+  int  (*value_bytes16)(sqlite3_value*);
+  double  (*value_double)(sqlite3_value*);
+  int  (*value_int)(sqlite3_value*);
+  sqlite_int64  (*value_int64)(sqlite3_value*);
+  int  (*value_numeric_type)(sqlite3_value*);
+  const unsigned char * (*value_text)(sqlite3_value*);
+  const void * (*value_text16)(sqlite3_value*);
+  const void * (*value_text16be)(sqlite3_value*);
+  const void * (*value_text16le)(sqlite3_value*);
+  int  (*value_type)(sqlite3_value*);
+  char *(*vmprintf)(const char*,va_list);
+  /* Added ??? */
+  int (*overload_function)(sqlite3*, const char *zFuncName, int nArg);
+  /* Added by 3.3.13 */
+  int (*prepare_v2)(sqlite3*,const char*,int,sqlite3_stmt**,const char**);
+  int (*prepare16_v2)(sqlite3*,const void*,int,sqlite3_stmt**,const void**);
+  int (*clear_bindings)(sqlite3_stmt*);
+  /* Added by 3.4.1 */
+  int (*create_module_v2)(sqlite3*,const char*,const sqlite3_module*,void*,void (*xDestroy)(void *));
+  /* Added by 3.5.0 */
+  int (*bind_zeroblob)(sqlite3_stmt*,int,int);
+  int (*blob_bytes)(sqlite3_blob*);
+  int (*blob_close)(sqlite3_blob*);
+  int (*blob_open)(sqlite3*,const char*,const char*,const char*,sqlite3_int64,int,sqlite3_blob**);
+  int (*blob_read)(sqlite3_blob*,void*,int,int);
+  int (*blob_write)(sqlite3_blob*,const void*,int,int);
+  int (*create_collation_v2)(sqlite3*,const char*,int,void*,int(*)(void*,int,const void*,int,const void*),void(*)(void*));
+  int (*file_control)(sqlite3*,const char*,int,void*);
+  sqlite3_int64 (*memory_highwater)(int);
+  sqlite3_int64 (*memory_used)(void);
+  sqlite3_mutex *(*mutex_alloc)(int);
+  void (*mutex_enter)(sqlite3_mutex*);
+  void (*mutex_free)(sqlite3_mutex*);
+  void (*mutex_leave)(sqlite3_mutex*);
+  int (*mutex_try)(sqlite3_mutex*);
+  int (*open_v2)(const char*,sqlite3**,int,const char*);
+  int (*release_memory)(int);
+  void (*result_error_nomem)(sqlite3_context*);
+  void (*result_error_toobig)(sqlite3_context*);
+  int (*sleep)(int);
+  void (*soft_heap_limit)(int);
+  sqlite3_vfs *(*vfs_find)(const char*);
+  int (*vfs_register)(sqlite3_vfs*,int);
+  int (*vfs_unregister)(sqlite3_vfs*);
+  int (*xthreadsafe)(void);
+  void (*result_zeroblob)(sqlite3_context*,int);
+  void (*result_error_code)(sqlite3_context*,int);
+  int (*test_control)(int, ...);
+  void (*randomness)(int,void*);
+  sqlite3 *(*context_db_handle)(sqlite3_context*);
+  int (*extended_result_codes)(sqlite3*,int);
+  int (*limit)(sqlite3*,int,int);
+  sqlite3_stmt *(*next_stmt)(sqlite3*,sqlite3_stmt*);
+  const char *(*sql)(sqlite3_stmt*);
+  int (*status)(int,int*,int*,int);
+};
+
+/*
+** The following macros redefine the API routines so that they are
+** redirected throught the global sqlite3_api structure.
+**
+** This header file is also used by the loadext.c source file
+** (part of the main SQLite library - not an extension) so that
+** it can get access to the sqlite3_api_routines structure
+** definition.  But the main library does not want to redefine
+** the API.  So the redefinition macros are only valid if the
+** SQLITE_CORE macros is undefined.
+*/
+#ifndef SQLITE_CORE
+#define sqlite3_aggregate_context      sqlite3_api->aggregate_context
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_aggregate_count        sqlite3_api->aggregate_count
+#endif
+#define sqlite3_bind_blob              sqlite3_api->bind_blob
+#define sqlite3_bind_double            sqlite3_api->bind_double
+#define sqlite3_bind_int               sqlite3_api->bind_int
+#define sqlite3_bind_int64             sqlite3_api->bind_int64
+#define sqlite3_bind_null              sqlite3_api->bind_null
+#define sqlite3_bind_parameter_count   sqlite3_api->bind_parameter_count
+#define sqlite3_bind_parameter_index   sqlite3_api->bind_parameter_index
+#define sqlite3_bind_parameter_name    sqlite3_api->bind_parameter_name
+#define sqlite3_bind_text              sqlite3_api->bind_text
+#define sqlite3_bind_text16            sqlite3_api->bind_text16
+#define sqlite3_bind_value             sqlite3_api->bind_value
+#define sqlite3_busy_handler           sqlite3_api->busy_handler
+#define sqlite3_busy_timeout           sqlite3_api->busy_timeout
+#define sqlite3_changes                sqlite3_api->changes
+#define sqlite3_close                  sqlite3_api->close
+#define sqlite3_collation_needed       sqlite3_api->collation_needed
+#define sqlite3_collation_needed16     sqlite3_api->collation_needed16
+#define sqlite3_column_blob            sqlite3_api->column_blob
+#define sqlite3_column_bytes           sqlite3_api->column_bytes
+#define sqlite3_column_bytes16         sqlite3_api->column_bytes16
+#define sqlite3_column_count           sqlite3_api->column_count
+#define sqlite3_column_database_name   sqlite3_api->column_database_name
+#define sqlite3_column_database_name16 sqlite3_api->column_database_name16
+#define sqlite3_column_decltype        sqlite3_api->column_decltype
+#define sqlite3_column_decltype16      sqlite3_api->column_decltype16
+#define sqlite3_column_double          sqlite3_api->column_double
+#define sqlite3_column_int             sqlite3_api->column_int
+#define sqlite3_column_int64           sqlite3_api->column_int64
+#define sqlite3_column_name            sqlite3_api->column_name
+#define sqlite3_column_name16          sqlite3_api->column_name16
+#define sqlite3_column_origin_name     sqlite3_api->column_origin_name
+#define sqlite3_column_origin_name16   sqlite3_api->column_origin_name16
+#define sqlite3_column_table_name      sqlite3_api->column_table_name
+#define sqlite3_column_table_name16    sqlite3_api->column_table_name16
+#define sqlite3_column_text            sqlite3_api->column_text
+#define sqlite3_column_text16          sqlite3_api->column_text16
+#define sqlite3_column_type            sqlite3_api->column_type
+#define sqlite3_column_value           sqlite3_api->column_value
+#define sqlite3_commit_hook            sqlite3_api->commit_hook
+#define sqlite3_complete               sqlite3_api->complete
+#define sqlite3_complete16             sqlite3_api->complete16
+#define sqlite3_create_collation       sqlite3_api->create_collation
+#define sqlite3_create_collation16     sqlite3_api->create_collation16
+#define sqlite3_create_function        sqlite3_api->create_function
+#define sqlite3_create_function16      sqlite3_api->create_function16
+#define sqlite3_create_module          sqlite3_api->create_module
+#define sqlite3_create_module_v2       sqlite3_api->create_module_v2
+#define sqlite3_data_count             sqlite3_api->data_count
+#define sqlite3_db_handle              sqlite3_api->db_handle
+#define sqlite3_declare_vtab           sqlite3_api->declare_vtab
+#define sqlite3_enable_shared_cache    sqlite3_api->enable_shared_cache
+#define sqlite3_errcode                sqlite3_api->errcode
+#define sqlite3_errmsg                 sqlite3_api->errmsg
+#define sqlite3_errmsg16               sqlite3_api->errmsg16
+#define sqlite3_exec                   sqlite3_api->exec
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_expired                sqlite3_api->expired
+#endif
+#define sqlite3_finalize               sqlite3_api->finalize
+#define sqlite3_free                   sqlite3_api->free
+#define sqlite3_free_table             sqlite3_api->free_table
+#define sqlite3_get_autocommit         sqlite3_api->get_autocommit
+#define sqlite3_get_auxdata            sqlite3_api->get_auxdata
+#define sqlite3_get_table              sqlite3_api->get_table
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_global_recover         sqlite3_api->global_recover
+#endif
+#define sqlite3_interrupt              sqlite3_api->interruptx
+#define sqlite3_last_insert_rowid      sqlite3_api->last_insert_rowid
+#define sqlite3_libversion             sqlite3_api->libversion
+#define sqlite3_libversion_number      sqlite3_api->libversion_number
+#define sqlite3_malloc                 sqlite3_api->malloc
+#define sqlite3_mprintf                sqlite3_api->mprintf
+#define sqlite3_open                   sqlite3_api->open
+#define sqlite3_open16                 sqlite3_api->open16
+#define sqlite3_prepare                sqlite3_api->prepare
+#define sqlite3_prepare16              sqlite3_api->prepare16
+#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
+#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
+#define sqlite3_profile                sqlite3_api->profile
+#define sqlite3_progress_handler       sqlite3_api->progress_handler
+#define sqlite3_realloc                sqlite3_api->realloc
+#define sqlite3_reset                  sqlite3_api->reset
+#define sqlite3_result_blob            sqlite3_api->result_blob
+#define sqlite3_result_double          sqlite3_api->result_double
+#define sqlite3_result_error           sqlite3_api->result_error
+#define sqlite3_result_error16         sqlite3_api->result_error16
+#define sqlite3_result_int             sqlite3_api->result_int
+#define sqlite3_result_int64           sqlite3_api->result_int64
+#define sqlite3_result_null            sqlite3_api->result_null
+#define sqlite3_result_text            sqlite3_api->result_text
+#define sqlite3_result_text16          sqlite3_api->result_text16
+#define sqlite3_result_text16be        sqlite3_api->result_text16be
+#define sqlite3_result_text16le        sqlite3_api->result_text16le
+#define sqlite3_result_value           sqlite3_api->result_value
+#define sqlite3_rollback_hook          sqlite3_api->rollback_hook
+#define sqlite3_set_authorizer         sqlite3_api->set_authorizer
+#define sqlite3_set_auxdata            sqlite3_api->set_auxdata
+#define sqlite3_snprintf               sqlite3_api->snprintf
+#define sqlite3_step                   sqlite3_api->step
+#define sqlite3_table_column_metadata  sqlite3_api->table_column_metadata
+#define sqlite3_thread_cleanup         sqlite3_api->thread_cleanup
+#define sqlite3_total_changes          sqlite3_api->total_changes
+#define sqlite3_trace                  sqlite3_api->trace
+#ifndef SQLITE_OMIT_DEPRECATED
+#define sqlite3_transfer_bindings      sqlite3_api->transfer_bindings
+#endif
+#define sqlite3_update_hook            sqlite3_api->update_hook
+#define sqlite3_user_data              sqlite3_api->user_data
+#define sqlite3_value_blob             sqlite3_api->value_blob
+#define sqlite3_value_bytes            sqlite3_api->value_bytes
+#define sqlite3_value_bytes16          sqlite3_api->value_bytes16
+#define sqlite3_value_double           sqlite3_api->value_double
+#define sqlite3_value_int              sqlite3_api->value_int
+#define sqlite3_value_int64            sqlite3_api->value_int64
+#define sqlite3_value_numeric_type     sqlite3_api->value_numeric_type
+#define sqlite3_value_text             sqlite3_api->value_text
+#define sqlite3_value_text16           sqlite3_api->value_text16
+#define sqlite3_value_text16be         sqlite3_api->value_text16be
+#define sqlite3_value_text16le         sqlite3_api->value_text16le
+#define sqlite3_value_type             sqlite3_api->value_type
+#define sqlite3_vmprintf               sqlite3_api->vmprintf
+#define sqlite3_overload_function      sqlite3_api->overload_function
+#define sqlite3_prepare_v2             sqlite3_api->prepare_v2
+#define sqlite3_prepare16_v2           sqlite3_api->prepare16_v2
+#define sqlite3_clear_bindings         sqlite3_api->clear_bindings
+#define sqlite3_bind_zeroblob          sqlite3_api->bind_zeroblob
+#define sqlite3_blob_bytes             sqlite3_api->blob_bytes
+#define sqlite3_blob_close             sqlite3_api->blob_close
+#define sqlite3_blob_open              sqlite3_api->blob_open
+#define sqlite3_blob_read              sqlite3_api->blob_read
+#define sqlite3_blob_write             sqlite3_api->blob_write
+#define sqlite3_create_collation_v2    sqlite3_api->create_collation_v2
+#define sqlite3_file_control           sqlite3_api->file_control
+#define sqlite3_memory_highwater       sqlite3_api->memory_highwater
+#define sqlite3_memory_used            sqlite3_api->memory_used
+#define sqlite3_mutex_alloc            sqlite3_api->mutex_alloc
+#define sqlite3_mutex_enter            sqlite3_api->mutex_enter
+#define sqlite3_mutex_free             sqlite3_api->mutex_free
+#define sqlite3_mutex_leave            sqlite3_api->mutex_leave
+#define sqlite3_mutex_try              sqlite3_api->mutex_try
+#define sqlite3_open_v2                sqlite3_api->open_v2
+#define sqlite3_release_memory         sqlite3_api->release_memory
+#define sqlite3_result_error_nomem     sqlite3_api->result_error_nomem
+#define sqlite3_result_error_toobig    sqlite3_api->result_error_toobig
+#define sqlite3_sleep                  sqlite3_api->sleep
+#define sqlite3_soft_heap_limit        sqlite3_api->soft_heap_limit
+#define sqlite3_vfs_find               sqlite3_api->vfs_find
+#define sqlite3_vfs_register           sqlite3_api->vfs_register
+#define sqlite3_vfs_unregister         sqlite3_api->vfs_unregister
+#define sqlite3_threadsafe             sqlite3_api->xthreadsafe
+#define sqlite3_result_zeroblob        sqlite3_api->result_zeroblob
+#define sqlite3_result_error_code      sqlite3_api->result_error_code
+#define sqlite3_test_control           sqlite3_api->test_control
+#define sqlite3_randomness             sqlite3_api->randomness
+#define sqlite3_context_db_handle      sqlite3_api->context_db_handle
+#define sqlite3_extended_result_codes  sqlite3_api->extended_result_codes
+#define sqlite3_limit                  sqlite3_api->limit
+#define sqlite3_next_stmt              sqlite3_api->next_stmt
+#define sqlite3_sql                    sqlite3_api->sql
+#define sqlite3_status                 sqlite3_api->status
+#endif /* SQLITE_CORE */
+
+#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
+#define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
+
+#endif /* _SQLITE3EXT_H_ */
+
+/************** End of sqlite3ext.h ******************************************/
+/************** Continuing where we left off in loadext.c ********************/
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+
+/*
+** Some API routines are omitted when various features are
+** excluded from a build of SQLite.  Substitute a NULL pointer
+** for any missing APIs.
+*/
+#ifndef SQLITE_ENABLE_COLUMN_METADATA
+# define sqlite3_column_database_name   0
+# define sqlite3_column_database_name16 0
+# define sqlite3_column_table_name      0
+# define sqlite3_column_table_name16    0
+# define sqlite3_column_origin_name     0
+# define sqlite3_column_origin_name16   0
+# define sqlite3_table_column_metadata  0
+#endif
+
+#ifdef SQLITE_OMIT_AUTHORIZATION
+# define sqlite3_set_authorizer         0
+#endif
+
+#ifdef SQLITE_OMIT_UTF16
+# define sqlite3_bind_text16            0
+# define sqlite3_collation_needed16     0
+# define sqlite3_column_decltype16      0
+# define sqlite3_column_name16          0
+# define sqlite3_column_text16          0
+# define sqlite3_complete16             0
+# define sqlite3_create_collation16     0
+# define sqlite3_create_function16      0
+# define sqlite3_errmsg16               0
+# define sqlite3_open16                 0
+# define sqlite3_prepare16              0
+# define sqlite3_prepare16_v2           0
+# define sqlite3_result_error16         0
+# define sqlite3_result_text16          0
+# define sqlite3_result_text16be        0
+# define sqlite3_result_text16le        0
+# define sqlite3_value_text16           0
+# define sqlite3_value_text16be         0
+# define sqlite3_value_text16le         0
+# define sqlite3_column_database_name16 0
+# define sqlite3_column_table_name16    0
+# define sqlite3_column_origin_name16   0
+#endif
+
+#ifdef SQLITE_OMIT_COMPLETE
+# define sqlite3_complete 0
+# define sqlite3_complete16 0
+#endif
+
+#ifdef SQLITE_OMIT_PROGRESS_CALLBACK
+# define sqlite3_progress_handler 0
+#endif
+
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+# define sqlite3_create_module 0
+# define sqlite3_create_module_v2 0
+# define sqlite3_declare_vtab 0
+#endif
+
+#ifdef SQLITE_OMIT_SHARED_CACHE
+# define sqlite3_enable_shared_cache 0
+#endif
+
+#ifdef SQLITE_OMIT_TRACE
+# define sqlite3_profile       0
+# define sqlite3_trace         0
+#endif
+
+#ifdef SQLITE_OMIT_GET_TABLE
+# define sqlite3_free_table    0
+# define sqlite3_get_table     0
+#endif
+
+#ifdef SQLITE_OMIT_INCRBLOB
+#define sqlite3_bind_zeroblob  0
+#define sqlite3_blob_bytes     0
+#define sqlite3_blob_close     0
+#define sqlite3_blob_open      0
+#define sqlite3_blob_read      0
+#define sqlite3_blob_write     0
+#endif
+
+/*
+** The following structure contains pointers to all SQLite API routines.
+** A pointer to this structure is passed into extensions when they are
+** loaded so that the extension can make calls back into the SQLite
+** library.
+**
+** When adding new APIs, add them to the bottom of this structure
+** in order to preserve backwards compatibility.
+**
+** Extensions that use newer APIs should first call the
+** sqlite3_libversion_number() to make sure that the API they
+** intend to use is supported by the library.  Extensions should
+** also check to make sure that the pointer to the function is
+** not NULL before calling it.
+*/
+static const sqlite3_api_routines sqlite3Apis = {
+  sqlite3_aggregate_context,
+#ifndef SQLITE_OMIT_DEPRECATED
+  sqlite3_aggregate_count,
+#else
+  0,
+#endif
+  sqlite3_bind_blob,
+  sqlite3_bind_double,
+  sqlite3_bind_int,
+  sqlite3_bind_int64,
+  sqlite3_bind_null,
+  sqlite3_bind_parameter_count,
+  sqlite3_bind_parameter_index,
+  sqlite3_bind_parameter_name,
+  sqlite3_bind_text,
+  sqlite3_bind_text16,
+  sqlite3_bind_value,
+  sqlite3_busy_handler,
+  sqlite3_busy_timeout,
+  sqlite3_changes,
+  sqlite3_close,
+  sqlite3_collation_needed,
+  sqlite3_collation_needed16,
+  sqlite3_column_blob,
+  sqlite3_column_bytes,
+  sqlite3_column_bytes16,
+  sqlite3_column_count,
+  sqlite3_column_database_name,
+  sqlite3_column_database_name16,
+  sqlite3_column_decltype,
+  sqlite3_column_decltype16,
+  sqlite3_column_double,
+  sqlite3_column_int,
+  sqlite3_column_int64,
+  sqlite3_column_name,
+  sqlite3_column_name16,
+  sqlite3_column_origin_name,
+  sqlite3_column_origin_name16,
+  sqlite3_column_table_name,
+  sqlite3_column_table_name16,
+  sqlite3_column_text,
+  sqlite3_column_text16,
+  sqlite3_column_type,
+  sqlite3_column_value,
+  sqlite3_commit_hook,
+  sqlite3_complete,
+  sqlite3_complete16,
+  sqlite3_create_collation,
+  sqlite3_create_collation16,
+  sqlite3_create_function,
+  sqlite3_create_function16,
+  sqlite3_create_module,
+  sqlite3_data_count,
+  sqlite3_db_handle,
+  sqlite3_declare_vtab,
+  sqlite3_enable_shared_cache,
+  sqlite3_errcode,
+  sqlite3_errmsg,
+  sqlite3_errmsg16,
+  sqlite3_exec,
+#ifndef SQLITE_OMIT_DEPRECATED
+  sqlite3_expired,
+#else
+  0,
+#endif
+  sqlite3_finalize,
+  sqlite3_free,
+  sqlite3_free_table,
+  sqlite3_get_autocommit,
+  sqlite3_get_auxdata,
+  sqlite3_get_table,
+  0,     /* Was sqlite3_global_recover(), but that function is deprecated */
+  sqlite3_interrupt,
+  sqlite3_last_insert_rowid,
+  sqlite3_libversion,
+  sqlite3_libversion_number,
+  sqlite3_malloc,
+  sqlite3_mprintf,
+  sqlite3_open,
+  sqlite3_open16,
+  sqlite3_prepare,
+  sqlite3_prepare16,
+  sqlite3_profile,
+  sqlite3_progress_handler,
+  sqlite3_realloc,
+  sqlite3_reset,
+  sqlite3_result_blob,
+  sqlite3_result_double,
+  sqlite3_result_error,
+  sqlite3_result_error16,
+  sqlite3_result_int,
+  sqlite3_result_int64,
+  sqlite3_result_null,
+  sqlite3_result_text,
+  sqlite3_result_text16,
+  sqlite3_result_text16be,
+  sqlite3_result_text16le,
+  sqlite3_result_value,
+  sqlite3_rollback_hook,
+  sqlite3_set_authorizer,
+  sqlite3_set_auxdata,
+  sqlite3_snprintf,
+  sqlite3_step,
+  sqlite3_table_column_metadata,
+#ifndef SQLITE_OMIT_DEPRECATED
+  sqlite3_thread_cleanup,
+#else
+  0,
+#endif
+  sqlite3_total_changes,
+  sqlite3_trace,
+#ifndef SQLITE_OMIT_DEPRECATED
+  sqlite3_transfer_bindings,
+#else
+  0,
+#endif
+  sqlite3_update_hook,
+  sqlite3_user_data,
+  sqlite3_value_blob,
+  sqlite3_value_bytes,
+  sqlite3_value_bytes16,
+  sqlite3_value_double,
+  sqlite3_value_int,
+  sqlite3_value_int64,
+  sqlite3_value_numeric_type,
+  sqlite3_value_text,
+  sqlite3_value_text16,
+  sqlite3_value_text16be,
+  sqlite3_value_text16le,
+  sqlite3_value_type,
+  sqlite3_vmprintf,
+  /*
+  ** The original API set ends here.  All extensions can call any
+  ** of the APIs above provided that the pointer is not NULL.  But
+  ** before calling APIs that follow, extension should check the
+  ** sqlite3_libversion_number() to make sure they are dealing with
+  ** a library that is new enough to support that API.
+  *************************************************************************
+  */
+  sqlite3_overload_function,
+
+  /*
+  ** Added after 3.3.13
+  */
+  sqlite3_prepare_v2,
+  sqlite3_prepare16_v2,
+  sqlite3_clear_bindings,
+
+  /*
+  ** Added for 3.4.1
+  */
+  sqlite3_create_module_v2,
+
+  /*
+  ** Added for 3.5.0
+  */
+  sqlite3_bind_zeroblob,
+  sqlite3_blob_bytes,
+  sqlite3_blob_close,
+  sqlite3_blob_open,
+  sqlite3_blob_read,
+  sqlite3_blob_write,
+  sqlite3_create_collation_v2,
+  sqlite3_file_control,
+  sqlite3_memory_highwater,
+  sqlite3_memory_used,
+#ifdef SQLITE_MUTEX_OMIT
+  0, 
+  0, 
+  0,
+  0,
+  0,
+#else
+  sqlite3_mutex_alloc,
+  sqlite3_mutex_enter,
+  sqlite3_mutex_free,
+  sqlite3_mutex_leave,
+  sqlite3_mutex_try,
+#endif
+  sqlite3_open_v2,
+  sqlite3_release_memory,
+  sqlite3_result_error_nomem,
+  sqlite3_result_error_toobig,
+  sqlite3_sleep,
+  sqlite3_soft_heap_limit,
+  sqlite3_vfs_find,
+  sqlite3_vfs_register,
+  sqlite3_vfs_unregister,
+
+  /*
+  ** Added for 3.5.8
+  */
+  sqlite3_threadsafe,
+  sqlite3_result_zeroblob,
+  sqlite3_result_error_code,
+  sqlite3_test_control,
+  sqlite3_randomness,
+  sqlite3_context_db_handle,
+
+  /*
+  ** Added for 3.6.0
+  */
+  sqlite3_extended_result_codes,
+  sqlite3_limit,
+  sqlite3_next_stmt,
+  sqlite3_sql,
+  sqlite3_status,
+};
+
+/*
+** Attempt to load an SQLite extension library contained in the file
+** zFile.  The entry point is zProc.  zProc may be 0 in which case a
+** default entry point name (sqlite3_extension_init) is used.  Use
+** of the default name is recommended.
+**
+** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
+**
+** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 
+** error message text.  The calling function should free this memory
+** by calling sqlite3DbFree(db, ).
+*/
+static int sqlite3LoadExtension(
+  sqlite3 *db,          /* Load the extension into this database connection */
+  const char *zFile,    /* Name of the shared library containing extension */
+  const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
+  char **pzErrMsg       /* Put error message here if not 0 */
+){
+  sqlite3_vfs *pVfs = db->pVfs;
+  void *handle;
+  int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
+  char *zErrmsg = 0;
+  void **aHandle;
+  const int nMsg = 300;
+
+  if( pzErrMsg ) *pzErrMsg = 0;
+
+  /* Ticket #1863.  To avoid a creating security problems for older
+  ** applications that relink against newer versions of SQLite, the
+  ** ability to run load_extension is turned off by default.  One
+  ** must call sqlite3_enable_load_extension() to turn on extension
+  ** loading.  Otherwise you get the following error.
+  */
+  if( (db->flags & SQLITE_LoadExtension)==0 ){
+    if( pzErrMsg ){
+      *pzErrMsg = sqlite3_mprintf("not authorized");
+    }
+    return SQLITE_ERROR;
+  }
+
+  if( zProc==0 ){
+    zProc = "sqlite3_extension_init";
+  }
+
+  handle = sqlite3OsDlOpen(pVfs, zFile);
+  if( handle==0 ){
+    if( pzErrMsg ){
+      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      if( zErrmsg ){
+        sqlite3_snprintf(nMsg, zErrmsg, 
+            "unable to open shared library [%s]", zFile);
+        sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
+        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
+        sqlite3StackFree(db, zErrmsg);
+      }
+    }
+    return SQLITE_ERROR;
+  }
+  xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
+                   sqlite3OsDlSym(pVfs, handle, zProc);
+  if( xInit==0 ){
+    if( pzErrMsg ){
+      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      if( zErrmsg ){
+        sqlite3_snprintf(nMsg, zErrmsg,
+            "no entry point [%s] in shared library [%s]", zProc,zFile);
+        sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
+        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
+        sqlite3StackFree(db, zErrmsg);
+      }
+      sqlite3OsDlClose(pVfs, handle);
+    }
+    return SQLITE_ERROR;
+  }else if( xInit(db, &zErrmsg, &sqlite3Apis) ){
+    if( pzErrMsg ){
+      *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
+    }
+    sqlite3_free(zErrmsg);
+    sqlite3OsDlClose(pVfs, handle);
+    return SQLITE_ERROR;
+  }
+
+  /* Append the new shared library handle to the db->aExtension array. */
+  aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));
+  if( aHandle==0 ){
+    return SQLITE_NOMEM;
+  }
+  if( db->nExtension>0 ){
+    memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);
+  }
+  sqlite3DbFree(db, db->aExtension);
+  db->aExtension = aHandle;
+
+  db->aExtension[db->nExtension++] = handle;
+  return SQLITE_OK;
+}
+SQLITE_API int sqlite3_load_extension(
+  sqlite3 *db,          /* Load the extension into this database connection */
+  const char *zFile,    /* Name of the shared library containing extension */
+  const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
+  char **pzErrMsg       /* Put error message here if not 0 */
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  rc = sqlite3LoadExtension(db, zFile, zProc, pzErrMsg);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/*
+** Call this routine when the database connection is closing in order
+** to clean up loaded extensions
+*/
+SQLITE_PRIVATE void sqlite3CloseExtensions(sqlite3 *db){
+  int i;
+  assert( sqlite3_mutex_held(db->mutex) );
+  for(i=0; i<db->nExtension; i++){
+    sqlite3OsDlClose(db->pVfs, db->aExtension[i]);
+  }
+  sqlite3DbFree(db, db->aExtension);
+}
+
+/*
+** Enable or disable extension loading.  Extension loading is disabled by
+** default so as not to open security holes in older applications.
+*/
+SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
+  sqlite3_mutex_enter(db->mutex);
+  if( onoff ){
+    db->flags |= SQLITE_LoadExtension;
+  }else{
+    db->flags &= ~SQLITE_LoadExtension;
+  }
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
+
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+
+/*
+** The auto-extension code added regardless of whether or not extension
+** loading is supported.  We need a dummy sqlite3Apis pointer for that
+** code if regular extension loading is not available.  This is that
+** dummy pointer.
+*/
+#ifdef SQLITE_OMIT_LOAD_EXTENSION
+static const sqlite3_api_routines sqlite3Apis = { 0 };
+#endif
+
+
+/*
+** The following object holds the list of automatically loaded
+** extensions.
+**
+** This list is shared across threads.  The SQLITE_MUTEX_STATIC_MASTER
+** mutex must be held while accessing this list.
+*/
+typedef struct sqlite3AutoExtList sqlite3AutoExtList;
+static SQLITE_WSD struct sqlite3AutoExtList {
+  int nExt;              /* Number of entries in aExt[] */          
+  void (**aExt)(void);   /* Pointers to the extension init functions */
+} sqlite3Autoext = { 0, 0 };
+
+/* The "wsdAutoext" macro will resolve to the autoextension
+** state vector.  If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time.  In the more common
+** case where writable static data is supported, wsdStat can refer directly
+** to the "sqlite3Autoext" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdAutoextInit \
+  sqlite3AutoExtList *x = &GLOBAL(sqlite3AutoExtList,sqlite3Autoext)
+# define wsdAutoext x[0]
+#else
+# define wsdAutoextInit
+# define wsdAutoext sqlite3Autoext
+#endif
+
+
+/*
+** Register a statically linked extension that is automatically
+** loaded by every new database connection.
+*/
+SQLITE_API int sqlite3_auto_extension(void (*xInit)(void)){
+  int rc = SQLITE_OK;
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ){
+    return rc;
+  }else
+#endif
+  {
+    int i;
+#if SQLITE_THREADSAFE
+    sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+    wsdAutoextInit;
+    sqlite3_mutex_enter(mutex);
+    for(i=0; i<wsdAutoext.nExt; i++){
+      if( wsdAutoext.aExt[i]==xInit ) break;
+    }
+    if( i==wsdAutoext.nExt ){
+      int nByte = (wsdAutoext.nExt+1)*sizeof(wsdAutoext.aExt[0]);
+      void (**aNew)(void);
+      aNew = sqlite3_realloc(wsdAutoext.aExt, nByte);
+      if( aNew==0 ){
+        rc = SQLITE_NOMEM;
+      }else{
+        wsdAutoext.aExt = aNew;
+        wsdAutoext.aExt[wsdAutoext.nExt] = xInit;
+        wsdAutoext.nExt++;
+      }
+    }
+    sqlite3_mutex_leave(mutex);
+    assert( (rc&0xff)==rc );
+    return rc;
+  }
+}
+
+/*
+** Reset the automatic extension loading mechanism.
+*/
+SQLITE_API void sqlite3_reset_auto_extension(void){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize()==SQLITE_OK )
+#endif
+  {
+#if SQLITE_THREADSAFE
+    sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+    wsdAutoextInit;
+    sqlite3_mutex_enter(mutex);
+    sqlite3_free(wsdAutoext.aExt);
+    wsdAutoext.aExt = 0;
+    wsdAutoext.nExt = 0;
+    sqlite3_mutex_leave(mutex);
+  }
+}
+
+/*
+** Load all automatic extensions.
+**
+** If anything goes wrong, set an error in the database connection.
+*/
+SQLITE_PRIVATE void sqlite3AutoLoadExtensions(sqlite3 *db){
+  int i;
+  int go = 1;
+  int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
+
+  wsdAutoextInit;
+  if( wsdAutoext.nExt==0 ){
+    /* Common case: early out without every having to acquire a mutex */
+    return;
+  }
+  for(i=0; go; i++){
+    char *zErrmsg;
+#if SQLITE_THREADSAFE
+    sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+    sqlite3_mutex_enter(mutex);
+    if( i>=wsdAutoext.nExt ){
+      xInit = 0;
+      go = 0;
+    }else{
+      xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
+              wsdAutoext.aExt[i];
+    }
+    sqlite3_mutex_leave(mutex);
+    zErrmsg = 0;
+    if( xInit && xInit(db, &zErrmsg, &sqlite3Apis) ){
+      sqlite3Error(db, SQLITE_ERROR,
+            "automatic extension loading failed: %s", zErrmsg);
+      go = 0;
+    }
+    sqlite3_free(zErrmsg);
+  }
+}
+
+/************** End of loadext.c *********************************************/
+/************** Begin file pragma.c ******************************************/
+/*
+** 2003 April 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used to implement the PRAGMA command.
+**
+** $Id: pragma.c,v 1.214 2009/07/02 07:47:33 danielk1977 Exp $
+*/
+
+/* Ignore this whole file if pragmas are disabled
+*/
+#if !defined(SQLITE_OMIT_PRAGMA)
+
+/*
+** Interpret the given string as a safety level.  Return 0 for OFF,
+** 1 for ON or NORMAL and 2 for FULL.  Return 1 for an empty or 
+** unrecognized string argument.
+**
+** Note that the values returned are one less that the values that
+** should be passed into sqlite3BtreeSetSafetyLevel().  The is done
+** to support legacy SQL code.  The safety level used to be boolean
+** and older scripts may have used numbers 0 for OFF and 1 for ON.
+*/
+static u8 getSafetyLevel(const char *z){
+                             /* 123456789 123456789 */
+  static const char zText[] = "onoffalseyestruefull";
+  static const u8 iOffset[] = {0, 1, 2, 4, 9, 12, 16};
+  static const u8 iLength[] = {2, 2, 3, 5, 3, 4, 4};
+  static const u8 iValue[] =  {1, 0, 0, 0, 1, 1, 2};
+  int i, n;
+  if( sqlite3Isdigit(*z) ){
+    return (u8)atoi(z);
+  }
+  n = sqlite3Strlen30(z);
+  for(i=0; i<ArraySize(iLength); i++){
+    if( iLength[i]==n && sqlite3StrNICmp(&zText[iOffset[i]],z,n)==0 ){
+      return iValue[i];
+    }
+  }
+  return 1;
+}
+
+/*
+** Interpret the given string as a boolean value.
+*/
+static u8 getBoolean(const char *z){
+  return getSafetyLevel(z)&1;
+}
+
+/*
+** Interpret the given string as a locking mode value.
+*/
+static int getLockingMode(const char *z){
+  if( z ){
+    if( 0==sqlite3StrICmp(z, "exclusive") ) return PAGER_LOCKINGMODE_EXCLUSIVE;
+    if( 0==sqlite3StrICmp(z, "normal") ) return PAGER_LOCKINGMODE_NORMAL;
+  }
+  return PAGER_LOCKINGMODE_QUERY;
+}
+
+#ifndef SQLITE_OMIT_AUTOVACUUM
+/*
+** Interpret the given string as an auto-vacuum mode value.
+**
+** The following strings, "none", "full" and "incremental" are 
+** acceptable, as are their numeric equivalents: 0, 1 and 2 respectively.
+*/
+static int getAutoVacuum(const char *z){
+  int i;
+  if( 0==sqlite3StrICmp(z, "none") ) return BTREE_AUTOVACUUM_NONE;
+  if( 0==sqlite3StrICmp(z, "full") ) return BTREE_AUTOVACUUM_FULL;
+  if( 0==sqlite3StrICmp(z, "incremental") ) return BTREE_AUTOVACUUM_INCR;
+  i = atoi(z);
+  return (u8)((i>=0&&i<=2)?i:0);
+}
+#endif /* ifndef SQLITE_OMIT_AUTOVACUUM */
+
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+/*
+** Interpret the given string as a temp db location. Return 1 for file
+** backed temporary databases, 2 for the Red-Black tree in memory database
+** and 0 to use the compile-time default.
+*/
+static int getTempStore(const char *z){
+  if( z[0]>='0' && z[0]<='2' ){
+    return z[0] - '0';
+  }else if( sqlite3StrICmp(z, "file")==0 ){
+    return 1;
+  }else if( sqlite3StrICmp(z, "memory")==0 ){
+    return 2;
+  }else{
+    return 0;
+  }
+}
+#endif /* SQLITE_PAGER_PRAGMAS */
+
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+/*
+** Invalidate temp storage, either when the temp storage is changed
+** from default, or when 'file' and the temp_store_directory has changed
+*/
+static int invalidateTempStorage(Parse *pParse){
+  sqlite3 *db = pParse->db;
+  if( db->aDb[1].pBt!=0 ){
+    if( !db->autoCommit || sqlite3BtreeIsInReadTrans(db->aDb[1].pBt) ){
+      sqlite3ErrorMsg(pParse, "temporary storage cannot be changed "
+        "from within a transaction");
+      return SQLITE_ERROR;
+    }
+    sqlite3BtreeClose(db->aDb[1].pBt);
+    db->aDb[1].pBt = 0;
+    sqlite3ResetInternalSchema(db, 0);
+  }
+  return SQLITE_OK;
+}
+#endif /* SQLITE_PAGER_PRAGMAS */
+
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+/*
+** If the TEMP database is open, close it and mark the database schema
+** as needing reloading.  This must be done when using the SQLITE_TEMP_STORE
+** or DEFAULT_TEMP_STORE pragmas.
+*/
+static int changeTempStorage(Parse *pParse, const char *zStorageType){
+  int ts = getTempStore(zStorageType);
+  sqlite3 *db = pParse->db;
+  if( db->temp_store==ts ) return SQLITE_OK;
+  if( invalidateTempStorage( pParse ) != SQLITE_OK ){
+    return SQLITE_ERROR;
+  }
+  db->temp_store = (u8)ts;
+  return SQLITE_OK;
+}
+#endif /* SQLITE_PAGER_PRAGMAS */
+
+/*
+** Generate code to return a single integer value.
+*/
+static void returnSingleInt(Parse *pParse, const char *zLabel, i64 value){
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  int mem = ++pParse->nMem;
+  i64 *pI64 = sqlite3DbMallocRaw(pParse->db, sizeof(value));
+  if( pI64 ){
+    memcpy(pI64, &value, sizeof(value));
+  }
+  sqlite3VdbeAddOp4(v, OP_Int64, 0, mem, 0, (char*)pI64, P4_INT64);
+  sqlite3VdbeSetNumCols(v, 1);
+  sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, SQLITE_STATIC);
+  sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
+}
+
+#ifndef SQLITE_OMIT_FLAG_PRAGMAS
+/*
+** Check to see if zRight and zLeft refer to a pragma that queries
+** or changes one of the flags in db->flags.  Return 1 if so and 0 if not.
+** Also, implement the pragma.
+*/
+static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
+  static const struct sPragmaType {
+    const char *zName;  /* Name of the pragma */
+    int mask;           /* Mask for the db->flags value */
+  } aPragma[] = {
+    { "full_column_names",        SQLITE_FullColNames  },
+    { "short_column_names",       SQLITE_ShortColNames },
+    { "count_changes",            SQLITE_CountRows     },
+    { "empty_result_callbacks",   SQLITE_NullCallback  },
+    { "legacy_file_format",       SQLITE_LegacyFileFmt },
+    { "fullfsync",                SQLITE_FullFSync     },
+    { "reverse_unordered_selects", SQLITE_ReverseOrder  },
+#ifdef SQLITE_DEBUG
+    { "sql_trace",                SQLITE_SqlTrace      },
+    { "vdbe_listing",             SQLITE_VdbeListing   },
+    { "vdbe_trace",               SQLITE_VdbeTrace     },
+#endif
+#ifndef SQLITE_OMIT_CHECK
+    { "ignore_check_constraints", SQLITE_IgnoreChecks  },
+#endif
+    /* The following is VERY experimental */
+    { "writable_schema",          SQLITE_WriteSchema|SQLITE_RecoveryMode },
+    { "omit_readlock",            SQLITE_NoReadlock    },
+
+    /* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
+    ** flag if there are any active statements. */
+    { "read_uncommitted",         SQLITE_ReadUncommitted },
+    { "recursive_triggers",       SQLITE_RecTriggers },
+
+    /* This flag may only be set if both foreign-key and trigger support
+    ** are present in the build.  */
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+    { "foreign_keys",             SQLITE_ForeignKeys },
+#endif
+  };
+  int i;
+  const struct sPragmaType *p;
+  for(i=0, p=aPragma; i<ArraySize(aPragma); i++, p++){
+    if( sqlite3StrICmp(zLeft, p->zName)==0 ){
+      sqlite3 *db = pParse->db;
+      Vdbe *v;
+      v = sqlite3GetVdbe(pParse);
+      assert( v!=0 );  /* Already allocated by sqlite3Pragma() */
+      if( ALWAYS(v) ){
+        if( zRight==0 ){
+          returnSingleInt(pParse, p->zName, (db->flags & p->mask)!=0 );
+        }else{
+          int mask = p->mask;          /* Mask of bits to set or clear. */
+          if( db->autoCommit==0 ){
+            /* Foreign key support may not be enabled or disabled while not
+            ** in auto-commit mode.  */
+            mask &= ~(SQLITE_ForeignKeys);
+          }
+
+          if( getBoolean(zRight) ){
+            db->flags |= mask;
+          }else{
+            db->flags &= ~mask;
+          }
+
+          /* Many of the flag-pragmas modify the code generated by the SQL 
+          ** compiler (eg. count_changes). So add an opcode to expire all
+          ** compiled SQL statements after modifying a pragma value.
+          */
+          sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
+        }
+      }
+
+      return 1;
+    }
+  }
+  return 0;
+}
+#endif /* SQLITE_OMIT_FLAG_PRAGMAS */
+
+/*
+** Return a human-readable name for a constraint resolution action.
+*/
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+static const char *actionName(u8 action){
+  const char *zName;
+  switch( action ){
+    case OE_SetNull:  zName = "SET NULL";        break;
+    case OE_SetDflt:  zName = "SET DEFAULT";     break;
+    case OE_Cascade:  zName = "CASCADE";         break;
+    case OE_Restrict: zName = "RESTRICT";        break;
+    default:          zName = "NO ACTION";  
+                      assert( action==OE_None ); break;
+  }
+  return zName;
+}
+#endif
+
+/*
+** Process a pragma statement.  
+**
+** Pragmas are of this form:
+**
+**      PRAGMA [database.]id [= value]
+**
+** The identifier might also be a string.  The value is a string, and
+** identifier, or a number.  If minusFlag is true, then the value is
+** a number that was preceded by a minus sign.
+**
+** If the left side is "database.id" then pId1 is the database name
+** and pId2 is the id.  If the left side is just "id" then pId1 is the
+** id and pId2 is any empty string.
+*/
+SQLITE_PRIVATE void sqlite3Pragma(
+  Parse *pParse, 
+  Token *pId1,        /* First part of [database.]id field */
+  Token *pId2,        /* Second part of [database.]id field, or NULL */
+  Token *pValue,      /* Token for <value>, or NULL */
+  int minusFlag       /* True if a '-' sign preceded <value> */
+){
+  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
+  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
+  const char *zDb = 0;   /* The database name */
+  Token *pId;            /* Pointer to <id> token */
+  int iDb;               /* Database index for <database> */
+  sqlite3 *db = pParse->db;
+  Db *pDb;
+  Vdbe *v = pParse->pVdbe = sqlite3VdbeCreate(db);
+  if( v==0 ) return;
+  pParse->nMem = 2;
+
+  /* Interpret the [database.] part of the pragma statement. iDb is the
+  ** index of the database this pragma is being applied to in db.aDb[]. */
+  iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
+  if( iDb<0 ) return;
+  pDb = &db->aDb[iDb];
+
+  /* If the temp database has been explicitly named as part of the 
+  ** pragma, make sure it is open. 
+  */
+  if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
+    return;
+  }
+
+  zLeft = sqlite3NameFromToken(db, pId);
+  if( !zLeft ) return;
+  if( minusFlag ){
+    zRight = sqlite3MPrintf(db, "-%T", pValue);
+  }else{
+    zRight = sqlite3NameFromToken(db, pValue);
+  }
+
+  assert( pId2 );
+  zDb = pId2->n>0 ? pDb->zName : 0;
+  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
+    goto pragma_out;
+  }
+ 
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+  /*
+  **  PRAGMA [database.]default_cache_size
+  **  PRAGMA [database.]default_cache_size=N
+  **
+  ** The first form reports the current persistent setting for the
+  ** page cache size.  The value returned is the maximum number of
+  ** pages in the page cache.  The second form sets both the current
+  ** page cache size value and the persistent page cache size value
+  ** stored in the database file.
+  **
+  ** The default cache size is stored in meta-value 2 of page 1 of the
+  ** database file.  The cache size is actually the absolute value of
+  ** this memory location.  The sign of meta-value 2 determines the
+  ** synchronous setting.  A negative value means synchronous is off
+  ** and a positive value means synchronous is on.
+  */
+  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
+    static const VdbeOpList getCacheSize[] = {
+      { OP_Transaction, 0, 0,        0},                         /* 0 */
+      { OP_ReadCookie,  0, 1,        BTREE_DEFAULT_CACHE_SIZE},  /* 1 */
+      { OP_IfPos,       1, 7,        0},
+      { OP_Integer,     0, 2,        0},
+      { OP_Subtract,    1, 2,        1},
+      { OP_IfPos,       1, 7,        0},
+      { OP_Integer,     0, 1,        0},                         /* 6 */
+      { OP_ResultRow,   1, 1,        0},
+    };
+    int addr;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    sqlite3VdbeUsesBtree(v, iDb);
+    if( !zRight ){
+      sqlite3VdbeSetNumCols(v, 1);
+      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", SQLITE_STATIC);
+      pParse->nMem += 2;
+      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
+      sqlite3VdbeChangeP1(v, addr, iDb);
+      sqlite3VdbeChangeP1(v, addr+1, iDb);
+      sqlite3VdbeChangeP1(v, addr+6, SQLITE_DEFAULT_CACHE_SIZE);
+    }else{
+      int size = atoi(zRight);
+      if( size<0 ) size = -size;
+      sqlite3BeginWriteOperation(pParse, 0, iDb);
+      sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
+      sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, 2, BTREE_DEFAULT_CACHE_SIZE);
+      addr = sqlite3VdbeAddOp2(v, OP_IfPos, 2, 0);
+      sqlite3VdbeAddOp2(v, OP_Integer, -size, 1);
+      sqlite3VdbeJumpHere(v, addr);
+      sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_DEFAULT_CACHE_SIZE, 1);
+      pDb->pSchema->cache_size = size;
+      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+    }
+  }else
+
+  /*
+  **  PRAGMA [database.]page_size
+  **  PRAGMA [database.]page_size=N
+  **
+  ** The first form reports the current setting for the
+  ** database page size in bytes.  The second form sets the
+  ** database page size value.  The value can only be set if
+  ** the database has not yet been created.
+  */
+  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
+    Btree *pBt = pDb->pBt;
+    assert( pBt!=0 );
+    if( !zRight ){
+      int size = ALWAYS(pBt) ? sqlite3BtreeGetPageSize(pBt) : 0;
+      returnSingleInt(pParse, "page_size", size);
+    }else{
+      /* Malloc may fail when setting the page-size, as there is an internal
+      ** buffer that the pager module resizes using sqlite3_realloc().
+      */
+      db->nextPagesize = atoi(zRight);
+      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1, 0) ){
+        db->mallocFailed = 1;
+      }
+    }
+  }else
+
+  /*
+  **  PRAGMA [database.]max_page_count
+  **  PRAGMA [database.]max_page_count=N
+  **
+  ** The first form reports the current setting for the
+  ** maximum number of pages in the database file.  The 
+  ** second form attempts to change this setting.  Both
+  ** forms return the current setting.
+  */
+  if( sqlite3StrICmp(zLeft,"max_page_count")==0 ){
+    Btree *pBt = pDb->pBt;
+    int newMax = 0;
+    assert( pBt!=0 );
+    if( zRight ){
+      newMax = atoi(zRight);
+    }
+    if( ALWAYS(pBt) ){
+      newMax = sqlite3BtreeMaxPageCount(pBt, newMax);
+    }
+    returnSingleInt(pParse, "max_page_count", newMax);
+  }else
+
+  /*
+  **  PRAGMA [database.]page_count
+  **
+  ** Return the number of pages in the specified database.
+  */
+  if( sqlite3StrICmp(zLeft,"page_count")==0 ){
+    int iReg;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    sqlite3CodeVerifySchema(pParse, iDb);
+    iReg = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Pagecount, iDb, iReg);
+    sqlite3VdbeAddOp2(v, OP_ResultRow, iReg, 1);
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "page_count", SQLITE_STATIC);
+  }else
+
+  /*
+  **  PRAGMA [database.]locking_mode
+  **  PRAGMA [database.]locking_mode = (normal|exclusive)
+  */
+  if( sqlite3StrICmp(zLeft,"locking_mode")==0 ){
+    const char *zRet = "normal";
+    int eMode = getLockingMode(zRight);
+
+    if( pId2->n==0 && eMode==PAGER_LOCKINGMODE_QUERY ){
+      /* Simple "PRAGMA locking_mode;" statement. This is a query for
+      ** the current default locking mode (which may be different to
+      ** the locking-mode of the main database).
+      */
+      eMode = db->dfltLockMode;
+    }else{
+      Pager *pPager;
+      if( pId2->n==0 ){
+        /* This indicates that no database name was specified as part
+        ** of the PRAGMA command. In this case the locking-mode must be
+        ** set on all attached databases, as well as the main db file.
+        **
+        ** Also, the sqlite3.dfltLockMode variable is set so that
+        ** any subsequently attached databases also use the specified
+        ** locking mode.
+        */
+        int ii;
+        assert(pDb==&db->aDb[0]);
+        for(ii=2; ii<db->nDb; ii++){
+          pPager = sqlite3BtreePager(db->aDb[ii].pBt);
+          sqlite3PagerLockingMode(pPager, eMode);
+        }
+        db->dfltLockMode = (u8)eMode;
+      }
+      pPager = sqlite3BtreePager(pDb->pBt);
+      eMode = sqlite3PagerLockingMode(pPager, eMode);
+    }
+
+    assert(eMode==PAGER_LOCKINGMODE_NORMAL||eMode==PAGER_LOCKINGMODE_EXCLUSIVE);
+    if( eMode==PAGER_LOCKINGMODE_EXCLUSIVE ){
+      zRet = "exclusive";
+    }
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "locking_mode", SQLITE_STATIC);
+    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
+    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+  }else
+
+  /*
+  **  PRAGMA [database.]journal_mode
+  **  PRAGMA [database.]journal_mode = (delete|persist|off|truncate|memory)
+  */
+  if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
+    int eMode;
+    static char * const azModeName[] = {
+      "delete", "persist", "off", "truncate", "memory"
+    };
+
+    if( zRight==0 ){
+      eMode = PAGER_JOURNALMODE_QUERY;
+    }else{
+      int n = sqlite3Strlen30(zRight);
+      eMode = sizeof(azModeName)/sizeof(azModeName[0]) - 1;
+      while( eMode>=0 && sqlite3StrNICmp(zRight, azModeName[eMode], n)!=0 ){
+        eMode--;
+      }
+    }
+    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
+      /* Simple "PRAGMA journal_mode;" statement. This is a query for
+      ** the current default journal mode (which may be different to
+      ** the journal-mode of the main database).
+      */
+      eMode = db->dfltJournalMode;
+    }else{
+      Pager *pPager;
+      if( pId2->n==0 ){
+        /* This indicates that no database name was specified as part
+        ** of the PRAGMA command. In this case the journal-mode must be
+        ** set on all attached databases, as well as the main db file.
+        **
+        ** Also, the sqlite3.dfltJournalMode variable is set so that
+        ** any subsequently attached databases also use the specified
+        ** journal mode.
+        */
+        int ii;
+        assert(pDb==&db->aDb[0]);
+        for(ii=1; ii<db->nDb; ii++){
+          if( db->aDb[ii].pBt ){
+            pPager = sqlite3BtreePager(db->aDb[ii].pBt);
+            sqlite3PagerJournalMode(pPager, eMode);
+          }
+        }
+        db->dfltJournalMode = (u8)eMode;
+      }
+      pPager = sqlite3BtreePager(pDb->pBt);
+      eMode = sqlite3PagerJournalMode(pPager, eMode);
+    }
+    assert( eMode==PAGER_JOURNALMODE_DELETE
+              || eMode==PAGER_JOURNALMODE_TRUNCATE
+              || eMode==PAGER_JOURNALMODE_PERSIST
+              || eMode==PAGER_JOURNALMODE_OFF
+              || eMode==PAGER_JOURNALMODE_MEMORY );
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", SQLITE_STATIC);
+    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, 
+           azModeName[eMode], P4_STATIC);
+    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+  }else
+
+  /*
+  **  PRAGMA [database.]journal_size_limit
+  **  PRAGMA [database.]journal_size_limit=N
+  **
+  ** Get or set the size limit on rollback journal files.
+  */
+  if( sqlite3StrICmp(zLeft,"journal_size_limit")==0 ){
+    Pager *pPager = sqlite3BtreePager(pDb->pBt);
+    i64 iLimit = -2;
+    if( zRight ){
+      sqlite3Atoi64(zRight, &iLimit);
+      if( iLimit<-1 ) iLimit = -1;
+    }
+    iLimit = sqlite3PagerJournalSizeLimit(pPager, iLimit);
+    returnSingleInt(pParse, "journal_size_limit", iLimit);
+  }else
+
+#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
+
+  /*
+  **  PRAGMA [database.]auto_vacuum
+  **  PRAGMA [database.]auto_vacuum=N
+  **
+  ** Get or set the value of the database 'auto-vacuum' parameter.
+  ** The value is one of:  0 NONE 1 FULL 2 INCREMENTAL
+  */
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
+    Btree *pBt = pDb->pBt;
+    assert( pBt!=0 );
+    if( sqlite3ReadSchema(pParse) ){
+      goto pragma_out;
+    }
+    if( !zRight ){
+      int auto_vacuum;
+      if( ALWAYS(pBt) ){
+         auto_vacuum = sqlite3BtreeGetAutoVacuum(pBt);
+      }else{
+         auto_vacuum = SQLITE_DEFAULT_AUTOVACUUM;
+      }
+      returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
+    }else{
+      int eAuto = getAutoVacuum(zRight);
+      assert( eAuto>=0 && eAuto<=2 );
+      db->nextAutovac = (u8)eAuto;
+      if( ALWAYS(eAuto>=0) ){
+        /* Call SetAutoVacuum() to set initialize the internal auto and
+        ** incr-vacuum flags. This is required in case this connection
+        ** creates the database file. It is important that it is created
+        ** as an auto-vacuum capable db.
+        */
+        int rc = sqlite3BtreeSetAutoVacuum(pBt, eAuto);
+        if( rc==SQLITE_OK && (eAuto==1 || eAuto==2) ){
+          /* When setting the auto_vacuum mode to either "full" or 
+          ** "incremental", write the value of meta[6] in the database
+          ** file. Before writing to meta[6], check that meta[3] indicates
+          ** that this really is an auto-vacuum capable database.
+          */
+          static const VdbeOpList setMeta6[] = {
+            { OP_Transaction,    0,         1,                 0},    /* 0 */
+            { OP_ReadCookie,     0,         1,         BTREE_LARGEST_ROOT_PAGE},
+            { OP_If,             1,         0,                 0},    /* 2 */
+            { OP_Halt,           SQLITE_OK, OE_Abort,          0},    /* 3 */
+            { OP_Integer,        0,         1,                 0},    /* 4 */
+            { OP_SetCookie,      0,         BTREE_INCR_VACUUM, 1},    /* 5 */
+          };
+          int iAddr;
+          iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);
+          sqlite3VdbeChangeP1(v, iAddr, iDb);
+          sqlite3VdbeChangeP1(v, iAddr+1, iDb);
+          sqlite3VdbeChangeP2(v, iAddr+2, iAddr+4);
+          sqlite3VdbeChangeP1(v, iAddr+4, eAuto-1);
+          sqlite3VdbeChangeP1(v, iAddr+5, iDb);
+          sqlite3VdbeUsesBtree(v, iDb);
+        }
+      }
+    }
+  }else
+#endif
+
+  /*
+  **  PRAGMA [database.]incremental_vacuum(N)
+  **
+  ** Do N steps of incremental vacuuming on a database.
+  */
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  if( sqlite3StrICmp(zLeft,"incremental_vacuum")==0 ){
+    int iLimit, addr;
+    if( sqlite3ReadSchema(pParse) ){
+      goto pragma_out;
+    }
+    if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
+      iLimit = 0x7fffffff;
+    }
+    sqlite3BeginWriteOperation(pParse, 0, iDb);
+    sqlite3VdbeAddOp2(v, OP_Integer, iLimit, 1);
+    addr = sqlite3VdbeAddOp1(v, OP_IncrVacuum, iDb);
+    sqlite3VdbeAddOp1(v, OP_ResultRow, 1);
+    sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
+    sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr);
+    sqlite3VdbeJumpHere(v, addr);
+  }else
+#endif
+
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+  /*
+  **  PRAGMA [database.]cache_size
+  **  PRAGMA [database.]cache_size=N
+  **
+  ** The first form reports the current local setting for the
+  ** page cache size.  The local setting can be different from
+  ** the persistent cache size value that is stored in the database
+  ** file itself.  The value returned is the maximum number of
+  ** pages in the page cache.  The second form sets the local
+  ** page cache size value.  It does not change the persistent
+  ** cache size stored on the disk so the cache size will revert
+  ** to its default value when the database is closed and reopened.
+  ** N should be a positive integer.
+  */
+  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    if( !zRight ){
+      returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
+    }else{
+      int size = atoi(zRight);
+      if( size<0 ) size = -size;
+      pDb->pSchema->cache_size = size;
+      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+    }
+  }else
+
+  /*
+  **   PRAGMA temp_store
+  **   PRAGMA temp_store = "default"|"memory"|"file"
+  **
+  ** Return or set the local value of the temp_store flag.  Changing
+  ** the local value does not make changes to the disk file and the default
+  ** value will be restored the next time the database is opened.
+  **
+  ** Note that it is possible for the library compile-time options to
+  ** override this setting
+  */
+  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
+    if( !zRight ){
+      returnSingleInt(pParse, "temp_store", db->temp_store);
+    }else{
+      changeTempStorage(pParse, zRight);
+    }
+  }else
+
+  /*
+  **   PRAGMA temp_store_directory
+  **   PRAGMA temp_store_directory = ""|"directory_name"
+  **
+  ** Return or set the local value of the temp_store_directory flag.  Changing
+  ** the value sets a specific directory to be used for temporary files.
+  ** Setting to a null string reverts to the default temporary directory search.
+  ** If temporary directory is changed, then invalidateTempStorage.
+  **
+  */
+  if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
+    if( !zRight ){
+      if( sqlite3_temp_directory ){
+        sqlite3VdbeSetNumCols(v, 1);
+        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
+            "temp_store_directory", SQLITE_STATIC);
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_temp_directory, 0);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+      }
+    }else{
+#ifndef SQLITE_OMIT_WSD
+      if( zRight[0] ){
+        int rc;
+        int res;
+        rc = sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE, &res);
+        if( rc!=SQLITE_OK || res==0 ){
+          sqlite3ErrorMsg(pParse, "not a writable directory");
+          goto pragma_out;
+        }
+      }
+      if( SQLITE_TEMP_STORE==0
+       || (SQLITE_TEMP_STORE==1 && db->temp_store<=1)
+       || (SQLITE_TEMP_STORE==2 && db->temp_store==1)
+      ){
+        invalidateTempStorage(pParse);
+      }
+      sqlite3_free(sqlite3_temp_directory);
+      if( zRight[0] ){
+        sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
+      }else{
+        sqlite3_temp_directory = 0;
+      }
+#endif /* SQLITE_OMIT_WSD */
+    }
+  }else
+
+#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
+#  if defined(__APPLE__)
+#    define SQLITE_ENABLE_LOCKING_STYLE 1
+#  else
+#    define SQLITE_ENABLE_LOCKING_STYLE 0
+#  endif
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE
+  /*
+   **   PRAGMA [database.]lock_proxy_file
+   **   PRAGMA [database.]lock_proxy_file = ":auto:"|"lock_file_path"
+   **
+   ** Return or set the value of the lock_proxy_file flag.  Changing
+   ** the value sets a specific file to be used for database access locks.
+   **
+   */
+  if( sqlite3StrICmp(zLeft, "lock_proxy_file")==0 ){
+    if( !zRight ){
+      Pager *pPager = sqlite3BtreePager(pDb->pBt);
+      char *proxy_file_path = NULL;
+      sqlite3_file *pFile = sqlite3PagerFile(pPager);
+      sqlite3OsFileControl(pFile, SQLITE_GET_LOCKPROXYFILE, 
+                           &proxy_file_path);
+      
+      if( proxy_file_path ){
+        sqlite3VdbeSetNumCols(v, 1);
+        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
+                              "lock_proxy_file", SQLITE_STATIC);
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, proxy_file_path, 0);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+      }
+    }else{
+      Pager *pPager = sqlite3BtreePager(pDb->pBt);
+      sqlite3_file *pFile = sqlite3PagerFile(pPager);
+      int res;
+      if( zRight[0] ){
+        res=sqlite3OsFileControl(pFile, SQLITE_SET_LOCKPROXYFILE, 
+                                     zRight);
+      } else {
+        res=sqlite3OsFileControl(pFile, SQLITE_SET_LOCKPROXYFILE, 
+                                     NULL);
+      }
+      if( res!=SQLITE_OK ){
+        sqlite3ErrorMsg(pParse, "failed to set lock proxy file");
+        goto pragma_out;
+      }
+    }
+  }else
+#endif /* SQLITE_ENABLE_LOCKING_STYLE */      
+    
+  /*
+  **   PRAGMA [database.]synchronous
+  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
+  **
+  ** Return or set the local value of the synchronous flag.  Changing
+  ** the local value does not make changes to the disk file and the
+  ** default value will be restored the next time the database is
+  ** opened.
+  */
+  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    if( !zRight ){
+      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
+    }else{
+      if( !db->autoCommit ){
+        sqlite3ErrorMsg(pParse, 
+            "Safety level may not be changed inside a transaction");
+      }else{
+        pDb->safety_level = getSafetyLevel(zRight)+1;
+      }
+    }
+  }else
+#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
+
+#ifndef SQLITE_OMIT_FLAG_PRAGMAS
+  if( flagPragma(pParse, zLeft, zRight) ){
+    /* The flagPragma() subroutine also generates any necessary code
+    ** there is nothing more to do here */
+  }else
+#endif /* SQLITE_OMIT_FLAG_PRAGMAS */
+
+#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
+  /*
+  **   PRAGMA table_info(<table>)
+  **
+  ** Return a single row for each column of the named table. The columns of
+  ** the returned data set are:
+  **
+  ** cid:        Column id (numbered from left to right, starting at 0)
+  ** name:       Column name
+  ** type:       Column declaration type.
+  ** notnull:    True if 'NOT NULL' is part of column declaration
+  ** dflt_value: The default value for the column, if any.
+  */
+  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
+    Table *pTab;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    pTab = sqlite3FindTable(db, zRight, zDb);
+    if( pTab ){
+      int i;
+      int nHidden = 0;
+      Column *pCol;
+      sqlite3VdbeSetNumCols(v, 6);
+      pParse->nMem = 6;
+      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "notnull", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "dflt_value", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "pk", SQLITE_STATIC);
+      sqlite3ViewGetColumnNames(pParse, pTab);
+      for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){
+        if( IsHiddenColumn(pCol) ){
+          nHidden++;
+          continue;
+        }
+        sqlite3VdbeAddOp2(v, OP_Integer, i-nHidden, 1);
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pCol->zName, 0);
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
+           pCol->zType ? pCol->zType : "", 0);
+        sqlite3VdbeAddOp2(v, OP_Integer, (pCol->notNull ? 1 : 0), 4);
+        if( pCol->zDflt ){
+          sqlite3VdbeAddOp4(v, OP_String8, 0, 5, 0, (char*)pCol->zDflt, 0);
+        }else{
+          sqlite3VdbeAddOp2(v, OP_Null, 0, 5);
+        }
+        sqlite3VdbeAddOp2(v, OP_Integer, pCol->isPrimKey, 6);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
+      }
+    }
+  }else
+
+  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
+    Index *pIdx;
+    Table *pTab;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    pIdx = sqlite3FindIndex(db, zRight, zDb);
+    if( pIdx ){
+      int i;
+      pTab = pIdx->pTable;
+      sqlite3VdbeSetNumCols(v, 3);
+      pParse->nMem = 3;
+      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", SQLITE_STATIC);
+      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", SQLITE_STATIC);
+      for(i=0; i<pIdx->nColumn; i++){
+        int cnum = pIdx->aiColumn[i];
+        sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
+        sqlite3VdbeAddOp2(v, OP_Integer, cnum, 2);
+        assert( pTab->nCol>cnum );
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pTab->aCol[cnum].zName, 0);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
+      }
+    }
+  }else
+
+  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
+    Index *pIdx;
+    Table *pTab;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    pTab = sqlite3FindTable(db, zRight, zDb);
+    if( pTab ){
+      v = sqlite3GetVdbe(pParse);
+      pIdx = pTab->pIndex;
+      if( pIdx ){
+        int i = 0; 
+        sqlite3VdbeSetNumCols(v, 3);
+        pParse->nMem = 3;
+        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", SQLITE_STATIC);
+        while(pIdx){
+          sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
+          sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
+          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
+          sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
+          ++i;
+          pIdx = pIdx->pNext;
+        }
+      }
+    }
+  }else
+
+  if( sqlite3StrICmp(zLeft, "database_list")==0 ){
+    int i;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    sqlite3VdbeSetNumCols(v, 3);
+    pParse->nMem = 3;
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", SQLITE_STATIC);
+    for(i=0; i<db->nDb; i++){
+      if( db->aDb[i].pBt==0 ) continue;
+      assert( db->aDb[i].zName!=0 );
+      sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, db->aDb[i].zName, 0);
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
+           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
+    }
+  }else
+
+  if( sqlite3StrICmp(zLeft, "collation_list")==0 ){
+    int i = 0;
+    HashElem *p;
+    sqlite3VdbeSetNumCols(v, 2);
+    pParse->nMem = 2;
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
+    for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
+      CollSeq *pColl = (CollSeq *)sqliteHashData(p);
+      sqlite3VdbeAddOp2(v, OP_Integer, i++, 1);
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pColl->zName, 0);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
+    }
+  }else
+#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
+    FKey *pFK;
+    Table *pTab;
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    pTab = sqlite3FindTable(db, zRight, zDb);
+    if( pTab ){
+      v = sqlite3GetVdbe(pParse);
+      pFK = pTab->pFKey;
+      if( pFK ){
+        int i = 0; 
+        sqlite3VdbeSetNumCols(v, 8);
+        pParse->nMem = 8;
+        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "on_update", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 6, COLNAME_NAME, "on_delete", SQLITE_STATIC);
+        sqlite3VdbeSetColName(v, 7, COLNAME_NAME, "match", SQLITE_STATIC);
+        while(pFK){
+          int j;
+          for(j=0; j<pFK->nCol; j++){
+            char *zCol = pFK->aCol[j].zCol;
+            char *zOnDelete = (char *)actionName(pFK->aAction[0]);
+            char *zOnUpdate = (char *)actionName(pFK->aAction[1]);
+            sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
+            sqlite3VdbeAddOp2(v, OP_Integer, j, 2);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pFK->zTo, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
+                              pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
+            sqlite3VdbeAddOp4(v, zCol ? OP_String8 : OP_Null, 0, 5, 0, zCol, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 6, 0, zOnUpdate, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 7, 0, zOnDelete, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 8, 0, "NONE", 0);
+            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 8);
+          }
+          ++i;
+          pFK = pFK->pNextFrom;
+        }
+      }
+    }
+  }else
+#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
+
+#ifndef NDEBUG
+  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
+    if( zRight ){
+      if( getBoolean(zRight) ){
+        sqlite3ParserTrace(stderr, "parser: ");
+      }else{
+        sqlite3ParserTrace(0, 0);
+      }
+    }
+  }else
+#endif
+
+  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
+  ** used will be case sensitive or not depending on the RHS.
+  */
+  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
+    if( zRight ){
+      sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
+    }
+  }else
+
+#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
+# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
+#endif
+
+#ifndef SQLITE_OMIT_INTEGRITY_CHECK
+  /* Pragma "quick_check" is an experimental reduced version of 
+  ** integrity_check designed to detect most database corruption
+  ** without most of the overhead of a full integrity-check.
+  */
+  if( sqlite3StrICmp(zLeft, "integrity_check")==0
+   || sqlite3StrICmp(zLeft, "quick_check")==0 
+  ){
+    int i, j, addr, mxErr;
+
+    /* Code that appears at the end of the integrity check.  If no error
+    ** messages have been generated, output OK.  Otherwise output the
+    ** error message
+    */
+    static const VdbeOpList endCode[] = {
+      { OP_AddImm,      1, 0,        0},    /* 0 */
+      { OP_IfNeg,       1, 0,        0},    /* 1 */
+      { OP_String8,     0, 3,        0},    /* 2 */
+      { OP_ResultRow,   3, 1,        0},
+    };
+
+    int isQuick = (zLeft[0]=='q');
+
+    /* Initialize the VDBE program */
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    pParse->nMem = 6;
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", SQLITE_STATIC);
+
+    /* Set the maximum error count */
+    mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
+    if( zRight ){
+      mxErr = atoi(zRight);
+      if( mxErr<=0 ){
+        mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
+      }
+    }
+    sqlite3VdbeAddOp2(v, OP_Integer, mxErr, 1);  /* reg[1] holds errors left */
+
+    /* Do an integrity check on each database file */
+    for(i=0; i<db->nDb; i++){
+      HashElem *x;
+      Hash *pTbls;
+      int cnt = 0;
+
+      if( OMIT_TEMPDB && i==1 ) continue;
+
+      sqlite3CodeVerifySchema(pParse, i);
+      addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
+      sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
+      sqlite3VdbeJumpHere(v, addr);
+
+      /* Do an integrity check of the B-Tree
+      **
+      ** Begin by filling registers 2, 3, ... with the root pages numbers
+      ** for all tables and indices in the database.
+      */
+      pTbls = &db->aDb[i].pSchema->tblHash;
+      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
+        Table *pTab = sqliteHashData(x);
+        Index *pIdx;
+        sqlite3VdbeAddOp2(v, OP_Integer, pTab->tnum, 2+cnt);
+        cnt++;
+        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->tnum, 2+cnt);
+          cnt++;
+        }
+      }
+
+      /* Make sure sufficient number of registers have been allocated */
+      if( pParse->nMem < cnt+4 ){
+        pParse->nMem = cnt+4;
+      }
+
+      /* Do the b-tree integrity checks */
+      sqlite3VdbeAddOp3(v, OP_IntegrityCk, 2, cnt, 1);
+      sqlite3VdbeChangeP5(v, (u8)i);
+      addr = sqlite3VdbeAddOp1(v, OP_IsNull, 2);
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
+         sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
+         P4_DYNAMIC);
+      sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
+      sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
+      sqlite3VdbeJumpHere(v, addr);
+
+      /* Make sure all the indices are constructed correctly.
+      */
+      for(x=sqliteHashFirst(pTbls); x && !isQuick; x=sqliteHashNext(x)){
+        Table *pTab = sqliteHashData(x);
+        Index *pIdx;
+        int loopTop;
+
+        if( pTab->pIndex==0 ) continue;
+        addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);  /* Stop if out of errors */
+        sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
+        sqlite3VdbeJumpHere(v, addr);
+        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, 2);  /* reg(2) will count entries */
+        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
+        sqlite3VdbeAddOp2(v, OP_AddImm, 2, 1);   /* increment entry count */
+        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
+          int jmp2;
+          static const VdbeOpList idxErr[] = {
+            { OP_AddImm,      1, -1,  0},
+            { OP_String8,     0,  3,  0},    /* 1 */
+            { OP_Rowid,       1,  4,  0},
+            { OP_String8,     0,  5,  0},    /* 3 */
+            { OP_String8,     0,  6,  0},    /* 4 */
+            { OP_Concat,      4,  3,  3},
+            { OP_Concat,      5,  3,  3},
+            { OP_Concat,      6,  3,  3},
+            { OP_ResultRow,   3,  1,  0},
+            { OP_IfPos,       1,  0,  0},    /* 9 */
+            { OP_Halt,        0,  0,  0},
+          };
+          sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 1);
+          jmp2 = sqlite3VdbeAddOp3(v, OP_Found, j+2, 0, 3);
+          addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
+          sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
+          sqlite3VdbeChangeP4(v, addr+3, " missing from index ", P4_STATIC);
+          sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
+          sqlite3VdbeJumpHere(v, addr+9);
+          sqlite3VdbeJumpHere(v, jmp2);
+        }
+        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
+        sqlite3VdbeJumpHere(v, loopTop);
+        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
+          static const VdbeOpList cntIdx[] = {
+             { OP_Integer,      0,  3,  0},
+             { OP_Rewind,       0,  0,  0},  /* 1 */
+             { OP_AddImm,       3,  1,  0},
+             { OP_Next,         0,  0,  0},  /* 3 */
+             { OP_Eq,           2,  0,  3},  /* 4 */
+             { OP_AddImm,       1, -1,  0},
+             { OP_String8,      0,  2,  0},  /* 6 */
+             { OP_String8,      0,  3,  0},  /* 7 */
+             { OP_Concat,       3,  2,  2},
+             { OP_ResultRow,    2,  1,  0},
+          };
+          addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);
+          sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
+          sqlite3VdbeJumpHere(v, addr);
+          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
+          sqlite3VdbeChangeP1(v, addr+1, j+2);
+          sqlite3VdbeChangeP2(v, addr+1, addr+4);
+          sqlite3VdbeChangeP1(v, addr+3, j+2);
+          sqlite3VdbeChangeP2(v, addr+3, addr+2);
+          sqlite3VdbeJumpHere(v, addr+4);
+          sqlite3VdbeChangeP4(v, addr+6, 
+                     "wrong # of entries in index ", P4_STATIC);
+          sqlite3VdbeChangeP4(v, addr+7, pIdx->zName, P4_STATIC);
+        }
+      } 
+    }
+    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
+    sqlite3VdbeChangeP2(v, addr, -mxErr);
+    sqlite3VdbeJumpHere(v, addr+1);
+    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
+  }else
+#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
+
+#ifndef SQLITE_OMIT_UTF16
+  /*
+  **   PRAGMA encoding
+  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
+  **
+  ** In its first form, this pragma returns the encoding of the main
+  ** database. If the database is not initialized, it is initialized now.
+  **
+  ** The second form of this pragma is a no-op if the main database file
+  ** has not already been initialized. In this case it sets the default
+  ** encoding that will be used for the main database file if a new file
+  ** is created. If an existing main database file is opened, then the
+  ** default text encoding for the existing database is used.
+  ** 
+  ** In all cases new databases created using the ATTACH command are
+  ** created to use the same default text encoding as the main database. If
+  ** the main database has not been initialized and/or created when ATTACH
+  ** is executed, this is done before the ATTACH operation.
+  **
+  ** In the second form this pragma sets the text encoding to be used in
+  ** new database files created using this database handle. It is only
+  ** useful if invoked immediately after the main database i
+  */
+  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
+    static const struct EncName {
+      char *zName;
+      u8 enc;
+    } encnames[] = {
+      { "UTF8",     SQLITE_UTF8        },
+      { "UTF-8",    SQLITE_UTF8        },  /* Must be element [1] */
+      { "UTF-16le", SQLITE_UTF16LE     },  /* Must be element [2] */
+      { "UTF-16be", SQLITE_UTF16BE     },  /* Must be element [3] */
+      { "UTF16le",  SQLITE_UTF16LE     },
+      { "UTF16be",  SQLITE_UTF16BE     },
+      { "UTF-16",   0                  }, /* SQLITE_UTF16NATIVE */
+      { "UTF16",    0                  }, /* SQLITE_UTF16NATIVE */
+      { 0, 0 }
+    };
+    const struct EncName *pEnc;
+    if( !zRight ){    /* "PRAGMA encoding" */
+      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+      sqlite3VdbeSetNumCols(v, 1);
+      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "encoding", SQLITE_STATIC);
+      sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
+      assert( encnames[SQLITE_UTF8].enc==SQLITE_UTF8 );
+      assert( encnames[SQLITE_UTF16LE].enc==SQLITE_UTF16LE );
+      assert( encnames[SQLITE_UTF16BE].enc==SQLITE_UTF16BE );
+      sqlite3VdbeChangeP4(v, -1, encnames[ENC(pParse->db)].zName, P4_STATIC);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+    }else{                        /* "PRAGMA encoding = XXX" */
+      /* Only change the value of sqlite.enc if the database handle is not
+      ** initialized. If the main database exists, the new sqlite.enc value
+      ** will be overwritten when the schema is next loaded. If it does not
+      ** already exists, it will be created to use the new encoding value.
+      */
+      if( 
+        !(DbHasProperty(db, 0, DB_SchemaLoaded)) || 
+        DbHasProperty(db, 0, DB_Empty) 
+      ){
+        for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
+          if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
+            ENC(pParse->db) = pEnc->enc ? pEnc->enc : SQLITE_UTF16NATIVE;
+            break;
+          }
+        }
+        if( !pEnc->zName ){
+          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
+        }
+      }
+    }
+  }else
+#endif /* SQLITE_OMIT_UTF16 */
+
+#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
+  /*
+  **   PRAGMA [database.]schema_version
+  **   PRAGMA [database.]schema_version = <integer>
+  **
+  **   PRAGMA [database.]user_version
+  **   PRAGMA [database.]user_version = <integer>
+  **
+  ** The pragma's schema_version and user_version are used to set or get
+  ** the value of the schema-version and user-version, respectively. Both
+  ** the schema-version and the user-version are 32-bit signed integers
+  ** stored in the database header.
+  **
+  ** The schema-cookie is usually only manipulated internally by SQLite. It
+  ** is incremented by SQLite whenever the database schema is modified (by
+  ** creating or dropping a table or index). The schema version is used by
+  ** SQLite each time a query is executed to ensure that the internal cache
+  ** of the schema used when compiling the SQL query matches the schema of
+  ** the database against which the compiled query is actually executed.
+  ** Subverting this mechanism by using "PRAGMA schema_version" to modify
+  ** the schema-version is potentially dangerous and may lead to program
+  ** crashes or database corruption. Use with caution!
+  **
+  ** The user-version is not used internally by SQLite. It may be used by
+  ** applications for any purpose.
+  */
+  if( sqlite3StrICmp(zLeft, "schema_version")==0 
+   || sqlite3StrICmp(zLeft, "user_version")==0 
+   || sqlite3StrICmp(zLeft, "freelist_count")==0 
+  ){
+    int iCookie;   /* Cookie index. 1 for schema-cookie, 6 for user-cookie. */
+    sqlite3VdbeUsesBtree(v, iDb);
+    switch( zLeft[0] ){
+      case 'f': case 'F':
+        iCookie = BTREE_FREE_PAGE_COUNT;
+        break;
+      case 's': case 'S':
+        iCookie = BTREE_SCHEMA_VERSION;
+        break;
+      default:
+        iCookie = BTREE_USER_VERSION;
+        break;
+    }
+
+    if( zRight && iCookie!=BTREE_FREE_PAGE_COUNT ){
+      /* Write the specified cookie value */
+      static const VdbeOpList setCookie[] = {
+        { OP_Transaction,    0,  1,  0},    /* 0 */
+        { OP_Integer,        0,  1,  0},    /* 1 */
+        { OP_SetCookie,      0,  0,  1},    /* 2 */
+      };
+      int addr = sqlite3VdbeAddOpList(v, ArraySize(setCookie), setCookie);
+      sqlite3VdbeChangeP1(v, addr, iDb);
+      sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
+      sqlite3VdbeChangeP1(v, addr+2, iDb);
+      sqlite3VdbeChangeP2(v, addr+2, iCookie);
+    }else{
+      /* Read the specified cookie value */
+      static const VdbeOpList readCookie[] = {
+        { OP_Transaction,     0,  0,  0},    /* 0 */
+        { OP_ReadCookie,      0,  1,  0},    /* 1 */
+        { OP_ResultRow,       1,  1,  0}
+      };
+      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
+      sqlite3VdbeChangeP1(v, addr, iDb);
+      sqlite3VdbeChangeP1(v, addr+1, iDb);
+      sqlite3VdbeChangeP3(v, addr+1, iCookie);
+      sqlite3VdbeSetNumCols(v, 1);
+      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, SQLITE_TRANSIENT);
+    }
+  }else
+#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */
+
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+  /*
+  ** Report the current state of file logs for all databases
+  */
+  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
+    static const char *const azLockName[] = {
+      "unlocked", "shared", "reserved", "pending", "exclusive"
+    };
+    int i;
+    sqlite3VdbeSetNumCols(v, 2);
+    pParse->nMem = 2;
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", SQLITE_STATIC);
+    for(i=0; i<db->nDb; i++){
+      Btree *pBt;
+      Pager *pPager;
+      const char *zState = "unknown";
+      int j;
+      if( db->aDb[i].zName==0 ) continue;
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, db->aDb[i].zName, P4_STATIC);
+      pBt = db->aDb[i].pBt;
+      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
+        zState = "closed";
+      }else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0, 
+                                     SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
+         zState = azLockName[j];
+      }
+      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
+    }
+
+  }else
+#endif
+
+#if SQLITE_HAS_CODEC
+  if( sqlite3StrICmp(zLeft, "key")==0 && zRight ){
+    sqlite3_key(db, zRight, sqlite3Strlen30(zRight));
+  }else
+  if( sqlite3StrICmp(zLeft, "rekey")==0 && zRight ){
+    sqlite3_rekey(db, zRight, sqlite3Strlen30(zRight));
+  }else
+  if( zRight && (sqlite3StrICmp(zLeft, "hexkey")==0 ||
+                 sqlite3StrICmp(zLeft, "hexrekey")==0) ){
+    int i, h1, h2;
+    char zKey[40];
+    for(i=0; (h1 = zRight[i])!=0 && (h2 = zRight[i+1])!=0; i+=2){
+      h1 += 9*(1&(h1>>6));
+      h2 += 9*(1&(h2>>6));
+      zKey[i/2] = (h2 & 0x0f) | ((h1 & 0xf)<<4);
+    }
+    if( (zLeft[3] & 0xf)==0xb ){
+      sqlite3_key(db, zKey, i/2);
+    }else{
+      sqlite3_rekey(db, zKey, i/2);
+    }
+  }else
+#endif
+#if SQLITE_HAS_CODEC || defined(SQLITE_ENABLE_CEROD)
+  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 ){
+#if SQLITE_HAS_CODEC
+    if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
+      extern void sqlite3_activate_see(const char*);
+      sqlite3_activate_see(&zRight[4]);
+    }
+#endif
+#ifdef SQLITE_ENABLE_CEROD
+    if( sqlite3StrNICmp(zRight, "cerod-", 6)==0 ){
+      extern void sqlite3_activate_cerod(const char*);
+      sqlite3_activate_cerod(&zRight[6]);
+    }
+#endif
+  }else
+#endif
+
+ 
+  {/* Empty ELSE clause */}
+
+  /* Code an OP_Expire at the end of each PRAGMA program to cause
+  ** the VDBE implementing the pragma to expire. Most (all?) pragmas
+  ** are only valid for a single execution.
+  */
+  sqlite3VdbeAddOp2(v, OP_Expire, 1, 0);
+
+  /*
+  ** Reset the safety level, in case the fullfsync flag or synchronous
+  ** setting changed.
+  */
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+  if( db->autoCommit ){
+    sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
+               (db->flags&SQLITE_FullFSync)!=0);
+  }
+#endif
+pragma_out:
+  sqlite3DbFree(db, zLeft);
+  sqlite3DbFree(db, zRight);
+}
+
+#endif /* SQLITE_OMIT_PRAGMA */
+
+/************** End of pragma.c **********************************************/
+/************** Begin file prepare.c *****************************************/
+/*
+** 2005 May 25
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the implementation of the sqlite3_prepare()
+** interface, and routines that contribute to loading the database schema
+** from disk.
+**
+** $Id: prepare.c,v 1.131 2009/08/06 17:43:31 drh Exp $
+*/
+
+/*
+** Fill the InitData structure with an error message that indicates
+** that the database is corrupt.
+*/
+static void corruptSchema(
+  InitData *pData,     /* Initialization context */
+  const char *zObj,    /* Object being parsed at the point of error */
+  const char *zExtra   /* Error information */
+){
+  sqlite3 *db = pData->db;
+  if( !db->mallocFailed && (db->flags & SQLITE_RecoveryMode)==0 ){
+    if( zObj==0 ) zObj = "?";
+    sqlite3SetString(pData->pzErrMsg, db,
+      "malformed database schema (%s)", zObj);
+    if( zExtra ){
+      *pData->pzErrMsg = sqlite3MAppendf(db, *pData->pzErrMsg, 
+                                 "%s - %s", *pData->pzErrMsg, zExtra);
+    }
+  }
+  pData->rc = db->mallocFailed ? SQLITE_NOMEM : SQLITE_CORRUPT;
+}
+
+/*
+** This is the callback routine for the code that initializes the
+** database.  See sqlite3Init() below for additional information.
+** This routine is also called from the OP_ParseSchema opcode of the VDBE.
+**
+** Each callback contains the following information:
+**
+**     argv[0] = name of thing being created
+**     argv[1] = root page number for table or index. 0 for trigger or view.
+**     argv[2] = SQL text for the CREATE statement.
+**
+*/
+SQLITE_PRIVATE int sqlite3InitCallback(void *pInit, int argc, char **argv, char **NotUsed){
+  InitData *pData = (InitData*)pInit;
+  sqlite3 *db = pData->db;
+  int iDb = pData->iDb;
+
+  assert( argc==3 );
+  UNUSED_PARAMETER2(NotUsed, argc);
+  assert( sqlite3_mutex_held(db->mutex) );
+  DbClearProperty(db, iDb, DB_Empty);
+  if( db->mallocFailed ){
+    corruptSchema(pData, argv[0], 0);
+    return 1;
+  }
+
+  assert( iDb>=0 && iDb<db->nDb );
+  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
+  if( argv[1]==0 ){
+    corruptSchema(pData, argv[0], 0);
+  }else if( argv[2] && argv[2][0] ){
+    /* Call the parser to process a CREATE TABLE, INDEX or VIEW.
+    ** But because db->init.busy is set to 1, no VDBE code is generated
+    ** or executed.  All the parser does is build the internal data
+    ** structures that describe the table, index, or view.
+    */
+    char *zErr;
+    int rc;
+    assert( db->init.busy );
+    db->init.iDb = iDb;
+    db->init.newTnum = atoi(argv[1]);
+    db->init.orphanTrigger = 0;
+    rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
+    db->init.iDb = 0;
+    assert( rc!=SQLITE_OK || zErr==0 );
+    if( SQLITE_OK!=rc ){
+      if( db->init.orphanTrigger ){
+        assert( iDb==1 );
+      }else{
+        pData->rc = rc;
+        if( rc==SQLITE_NOMEM ){
+          db->mallocFailed = 1;
+        }else if( rc!=SQLITE_INTERRUPT && rc!=SQLITE_LOCKED ){
+          corruptSchema(pData, argv[0], zErr);
+        }
+      }
+      sqlite3DbFree(db, zErr);
+    }
+  }else if( argv[0]==0 ){
+    corruptSchema(pData, 0, 0);
+  }else{
+    /* If the SQL column is blank it means this is an index that
+    ** was created to be the PRIMARY KEY or to fulfill a UNIQUE
+    ** constraint for a CREATE TABLE.  The index should have already
+    ** been created when we processed the CREATE TABLE.  All we have
+    ** to do here is record the root page number for that index.
+    */
+    Index *pIndex;
+    pIndex = sqlite3FindIndex(db, argv[0], db->aDb[iDb].zName);
+    if( pIndex==0 ){
+      /* This can occur if there exists an index on a TEMP table which
+      ** has the same name as another index on a permanent index.  Since
+      ** the permanent table is hidden by the TEMP table, we can also
+      ** safely ignore the index on the permanent table.
+      */
+      /* Do Nothing */;
+    }else if( sqlite3GetInt32(argv[1], &pIndex->tnum)==0 ){
+      corruptSchema(pData, argv[0], "invalid rootpage");
+    }
+  }
+  return 0;
+}
+
+/*
+** Attempt to read the database schema and initialize internal
+** data structures for a single database file.  The index of the
+** database file is given by iDb.  iDb==0 is used for the main
+** database.  iDb==1 should never be used.  iDb>=2 is used for
+** auxiliary databases.  Return one of the SQLITE_ error codes to
+** indicate success or failure.
+*/
+static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
+  int rc;
+  int i;
+  int size;
+  Table *pTab;
+  Db *pDb;
+  char const *azArg[4];
+  int meta[5];
+  InitData initData;
+  char const *zMasterSchema;
+  char const *zMasterName = SCHEMA_TABLE(iDb);
+  int openedTransaction = 0;
+
+  /*
+  ** The master database table has a structure like this
+  */
+  static const char master_schema[] = 
+     "CREATE TABLE sqlite_master(\n"
+     "  type text,\n"
+     "  name text,\n"
+     "  tbl_name text,\n"
+     "  rootpage integer,\n"
+     "  sql text\n"
+     ")"
+  ;
+#ifndef SQLITE_OMIT_TEMPDB
+  static const char temp_master_schema[] = 
+     "CREATE TEMP TABLE sqlite_temp_master(\n"
+     "  type text,\n"
+     "  name text,\n"
+     "  tbl_name text,\n"
+     "  rootpage integer,\n"
+     "  sql text\n"
+     ")"
+  ;
+#else
+  #define temp_master_schema 0
+#endif
+
+  assert( iDb>=0 && iDb<db->nDb );
+  assert( db->aDb[iDb].pSchema );
+  assert( sqlite3_mutex_held(db->mutex) );
+  assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
+
+  /* zMasterSchema and zInitScript are set to point at the master schema
+  ** and initialisation script appropriate for the database being
+  ** initialised. zMasterName is the name of the master table.
+  */
+  if( !OMIT_TEMPDB && iDb==1 ){
+    zMasterSchema = temp_master_schema;
+  }else{
+    zMasterSchema = master_schema;
+  }
+  zMasterName = SCHEMA_TABLE(iDb);
+
+  /* Construct the schema tables.  */
+  azArg[0] = zMasterName;
+  azArg[1] = "1";
+  azArg[2] = zMasterSchema;
+  azArg[3] = 0;
+  initData.db = db;
+  initData.iDb = iDb;
+  initData.rc = SQLITE_OK;
+  initData.pzErrMsg = pzErrMsg;
+  (void)sqlite3SafetyOff(db);
+  sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
+  (void)sqlite3SafetyOn(db);
+  if( initData.rc ){
+    rc = initData.rc;
+    goto error_out;
+  }
+  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
+  if( ALWAYS(pTab) ){
+    pTab->tabFlags |= TF_Readonly;
+  }
+
+  /* Create a cursor to hold the database open
+  */
+  pDb = &db->aDb[iDb];
+  if( pDb->pBt==0 ){
+    if( !OMIT_TEMPDB && ALWAYS(iDb==1) ){
+      DbSetProperty(db, 1, DB_SchemaLoaded);
+    }
+    return SQLITE_OK;
+  }
+
+  /* If there is not already a read-only (or read-write) transaction opened
+  ** on the b-tree database, open one now. If a transaction is opened, it 
+  ** will be closed before this function returns.  */
+  sqlite3BtreeEnter(pDb->pBt);
+  if( !sqlite3BtreeIsInReadTrans(pDb->pBt) ){
+    rc = sqlite3BtreeBeginTrans(pDb->pBt, 0);
+    if( rc!=SQLITE_OK ){
+      sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
+      goto initone_error_out;
+    }
+    openedTransaction = 1;
+  }
+
+  /* Get the database meta information.
+  **
+  ** Meta values are as follows:
+  **    meta[0]   Schema cookie.  Changes with each schema change.
+  **    meta[1]   File format of schema layer.
+  **    meta[2]   Size of the page cache.
+  **    meta[3]   Largest rootpage (auto/incr_vacuum mode)
+  **    meta[4]   Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
+  **    meta[5]   User version
+  **    meta[6]   Incremental vacuum mode
+  **    meta[7]   unused
+  **    meta[8]   unused
+  **    meta[9]   unused
+  **
+  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
+  ** the possible values of meta[4].
+  */
+  for(i=0; i<ArraySize(meta); i++){
+    sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
+  }
+  pDb->pSchema->schema_cookie = meta[BTREE_SCHEMA_VERSION-1];
+
+  /* If opening a non-empty database, check the text encoding. For the
+  ** main database, set sqlite3.enc to the encoding of the main database.
+  ** For an attached db, it is an error if the encoding is not the same
+  ** as sqlite3.enc.
+  */
+  if( meta[BTREE_TEXT_ENCODING-1] ){  /* text encoding */
+    if( iDb==0 ){
+      u8 encoding;
+      /* If opening the main database, set ENC(db). */
+      encoding = (u8)meta[BTREE_TEXT_ENCODING-1] & 3;
+      if( encoding==0 ) encoding = SQLITE_UTF8;
+      ENC(db) = encoding;
+      db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 0);
+    }else{
+      /* If opening an attached database, the encoding much match ENC(db) */
+      if( meta[BTREE_TEXT_ENCODING-1]!=ENC(db) ){
+        sqlite3SetString(pzErrMsg, db, "attached databases must use the same"
+            " text encoding as main database");
+        rc = SQLITE_ERROR;
+        goto initone_error_out;
+      }
+    }
+  }else{
+    DbSetProperty(db, iDb, DB_Empty);
+  }
+  pDb->pSchema->enc = ENC(db);
+
+  if( pDb->pSchema->cache_size==0 ){
+    size = meta[BTREE_DEFAULT_CACHE_SIZE-1];
+    if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
+    if( size<0 ) size = -size;
+    pDb->pSchema->cache_size = size;
+    sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+  }
+
+  /*
+  ** file_format==1    Version 3.0.0.
+  ** file_format==2    Version 3.1.3.  // ALTER TABLE ADD COLUMN
+  ** file_format==3    Version 3.1.4.  // ditto but with non-NULL defaults
+  ** file_format==4    Version 3.3.0.  // DESC indices.  Boolean constants
+  */
+  pDb->pSchema->file_format = (u8)meta[BTREE_FILE_FORMAT-1];
+  if( pDb->pSchema->file_format==0 ){
+    pDb->pSchema->file_format = 1;
+  }
+  if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
+    sqlite3SetString(pzErrMsg, db, "unsupported file format");
+    rc = SQLITE_ERROR;
+    goto initone_error_out;
+  }
+
+  /* Ticket #2804:  When we open a database in the newer file format,
+  ** clear the legacy_file_format pragma flag so that a VACUUM will
+  ** not downgrade the database and thus invalidate any descending
+  ** indices that the user might have created.
+  */
+  if( iDb==0 && meta[BTREE_FILE_FORMAT-1]>=4 ){
+    db->flags &= ~SQLITE_LegacyFileFmt;
+  }
+
+  /* Read the schema information out of the schema tables
+  */
+  assert( db->init.busy );
+  {
+    char *zSql;
+    zSql = sqlite3MPrintf(db, 
+        "SELECT name, rootpage, sql FROM '%q'.%s",
+        db->aDb[iDb].zName, zMasterName);
+    (void)sqlite3SafetyOff(db);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+    {
+      int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
+      xAuth = db->xAuth;
+      db->xAuth = 0;
+#endif
+      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+      db->xAuth = xAuth;
+    }
+#endif
+    if( rc==SQLITE_OK ) rc = initData.rc;
+    (void)sqlite3SafetyOn(db);
+    sqlite3DbFree(db, zSql);
+#ifndef SQLITE_OMIT_ANALYZE
+    if( rc==SQLITE_OK ){
+      sqlite3AnalysisLoad(db, iDb);
+    }
+#endif
+  }
+  if( db->mallocFailed ){
+    rc = SQLITE_NOMEM;
+    sqlite3ResetInternalSchema(db, 0);
+  }
+  if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
+    /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
+    ** the schema loaded, even if errors occurred. In this situation the 
+    ** current sqlite3_prepare() operation will fail, but the following one
+    ** will attempt to compile the supplied statement against whatever subset
+    ** of the schema was loaded before the error occurred. The primary
+    ** purpose of this is to allow access to the sqlite_master table
+    ** even when its contents have been corrupted.
+    */
+    DbSetProperty(db, iDb, DB_SchemaLoaded);
+    rc = SQLITE_OK;
+  }
+
+  /* Jump here for an error that occurs after successfully allocating
+  ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
+  ** before that point, jump to error_out.
+  */
+initone_error_out:
+  if( openedTransaction ){
+    sqlite3BtreeCommit(pDb->pBt);
+  }
+  sqlite3BtreeLeave(pDb->pBt);
+
+error_out:
+  if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
+    db->mallocFailed = 1;
+  }
+  return rc;
+}
+
+/*
+** Initialize all database files - the main database file, the file
+** used to store temporary tables, and any additional database files
+** created using ATTACH statements.  Return a success code.  If an
+** error occurs, write an error message into *pzErrMsg.
+**
+** After a database is initialized, the DB_SchemaLoaded bit is set
+** bit is set in the flags field of the Db structure. If the database
+** file was of zero-length, then the DB_Empty flag is also set.
+*/
+SQLITE_PRIVATE int sqlite3Init(sqlite3 *db, char **pzErrMsg){
+  int i, rc;
+  int commit_internal = !(db->flags&SQLITE_InternChanges);
+  
+  assert( sqlite3_mutex_held(db->mutex) );
+  rc = SQLITE_OK;
+  db->init.busy = 1;
+  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
+    if( DbHasProperty(db, i, DB_SchemaLoaded) || i==1 ) continue;
+    rc = sqlite3InitOne(db, i, pzErrMsg);
+    if( rc ){
+      sqlite3ResetInternalSchema(db, i);
+    }
+  }
+
+  /* Once all the other databases have been initialised, load the schema
+  ** for the TEMP database. This is loaded last, as the TEMP database
+  ** schema may contain references to objects in other databases.
+  */
+#ifndef SQLITE_OMIT_TEMPDB
+  if( rc==SQLITE_OK && ALWAYS(db->nDb>1)
+                    && !DbHasProperty(db, 1, DB_SchemaLoaded) ){
+    rc = sqlite3InitOne(db, 1, pzErrMsg);
+    if( rc ){
+      sqlite3ResetInternalSchema(db, 1);
+    }
+  }
+#endif
+
+  db->init.busy = 0;
+  if( rc==SQLITE_OK && commit_internal ){
+    sqlite3CommitInternalChanges(db);
+  }
+
+  return rc; 
+}
+
+/*
+** This routine is a no-op if the database schema is already initialised.
+** Otherwise, the schema is loaded. An error code is returned.
+*/
+SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse){
+  int rc = SQLITE_OK;
+  sqlite3 *db = pParse->db;
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( !db->init.busy ){
+    rc = sqlite3Init(db, &pParse->zErrMsg);
+  }
+  if( rc!=SQLITE_OK ){
+    pParse->rc = rc;
+    pParse->nErr++;
+  }
+  return rc;
+}
+
+
+/*
+** Check schema cookies in all databases.  If any cookie is out
+** of date set pParse->rc to SQLITE_SCHEMA.  If all schema cookies
+** make no changes to pParse->rc.
+*/
+static void schemaIsValid(Parse *pParse){
+  sqlite3 *db = pParse->db;
+  int iDb;
+  int rc;
+  int cookie;
+
+  assert( pParse->checkSchema );
+  assert( sqlite3_mutex_held(db->mutex) );
+  for(iDb=0; iDb<db->nDb; iDb++){
+    int openedTransaction = 0;         /* True if a transaction is opened */
+    Btree *pBt = db->aDb[iDb].pBt;     /* Btree database to read cookie from */
+    if( pBt==0 ) continue;
+
+    /* If there is not already a read-only (or read-write) transaction opened
+    ** on the b-tree database, open one now. If a transaction is opened, it 
+    ** will be closed immediately after reading the meta-value. */
+    if( !sqlite3BtreeIsInReadTrans(pBt) ){
+      rc = sqlite3BtreeBeginTrans(pBt, 0);
+      if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
+        db->mallocFailed = 1;
+      }
+      if( rc!=SQLITE_OK ) return;
+      openedTransaction = 1;
+    }
+
+    /* Read the schema cookie from the database. If it does not match the 
+    ** value stored as part of the in the in-memory schema representation,
+    ** set Parse.rc to SQLITE_SCHEMA. */
+    sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&cookie);
+    if( cookie!=db->aDb[iDb].pSchema->schema_cookie ){
+      pParse->rc = SQLITE_SCHEMA;
+    }
+
+    /* Close the transaction, if one was opened. */
+    if( openedTransaction ){
+      sqlite3BtreeCommit(pBt);
+    }
+  }
+}
+
+/*
+** Convert a schema pointer into the iDb index that indicates
+** which database file in db->aDb[] the schema refers to.
+**
+** If the same database is attached more than once, the first
+** attached database is returned.
+*/
+SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *pSchema){
+  int i = -1000000;
+
+  /* If pSchema is NULL, then return -1000000. This happens when code in 
+  ** expr.c is trying to resolve a reference to a transient table (i.e. one
+  ** created by a sub-select). In this case the return value of this 
+  ** function should never be used.
+  **
+  ** We return -1000000 instead of the more usual -1 simply because using
+  ** -1000000 as the incorrect index into db->aDb[] is much 
+  ** more likely to cause a segfault than -1 (of course there are assert()
+  ** statements too, but it never hurts to play the odds).
+  */
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( pSchema ){
+    for(i=0; ALWAYS(i<db->nDb); i++){
+      if( db->aDb[i].pSchema==pSchema ){
+        break;
+      }
+    }
+    assert( i>=0 && i<db->nDb );
+  }
+  return i;
+}
+
+/*
+** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
+*/
+static int sqlite3Prepare(
+  sqlite3 *db,              /* Database handle. */
+  const char *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  int saveSqlFlag,          /* True to copy SQL text into the sqlite3_stmt */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const char **pzTail       /* OUT: End of parsed string */
+){
+  Parse *pParse;            /* Parsing context */
+  char *zErrMsg = 0;        /* Error message */
+  int rc = SQLITE_OK;       /* Result code */
+  int i;                    /* Loop counter */
+
+  /* Allocate the parsing context */
+  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
+  if( pParse==0 ){
+    rc = SQLITE_NOMEM;
+    goto end_prepare;
+  }
+
+  if( sqlite3SafetyOn(db) ){
+    rc = SQLITE_MISUSE;
+    goto end_prepare;
+  }
+  assert( ppStmt && *ppStmt==0 );
+  assert( !db->mallocFailed );
+  assert( sqlite3_mutex_held(db->mutex) );
+
+  /* Check to verify that it is possible to get a read lock on all
+  ** database schemas.  The inability to get a read lock indicates that
+  ** some other database connection is holding a write-lock, which in
+  ** turn means that the other connection has made uncommitted changes
+  ** to the schema.
+  **
+  ** Were we to proceed and prepare the statement against the uncommitted
+  ** schema changes and if those schema changes are subsequently rolled
+  ** back and different changes are made in their place, then when this
+  ** prepared statement goes to run the schema cookie would fail to detect
+  ** the schema change.  Disaster would follow.
+  **
+  ** This thread is currently holding mutexes on all Btrees (because
+  ** of the sqlite3BtreeEnterAll() in sqlite3LockAndPrepare()) so it
+  ** is not possible for another thread to start a new schema change
+  ** while this routine is running.  Hence, we do not need to hold 
+  ** locks on the schema, we just need to make sure nobody else is 
+  ** holding them.
+  **
+  ** Note that setting READ_UNCOMMITTED overrides most lock detection,
+  ** but it does *not* override schema lock detection, so this all still
+  ** works even if READ_UNCOMMITTED is set.
+  */
+  for(i=0; i<db->nDb; i++) {
+    Btree *pBt = db->aDb[i].pBt;
+    if( pBt ){
+      assert( sqlite3BtreeHoldsMutex(pBt) );
+      rc = sqlite3BtreeSchemaLocked(pBt);
+      if( rc ){
+        const char *zDb = db->aDb[i].zName;
+        sqlite3Error(db, rc, "database schema is locked: %s", zDb);
+        (void)sqlite3SafetyOff(db);
+        testcase( db->flags & SQLITE_ReadUncommitted );
+        goto end_prepare;
+      }
+    }
+  }
+
+  sqlite3VtabUnlockList(db);
+
+  pParse->db = db;
+  if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
+    char *zSqlCopy;
+    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
+    testcase( nBytes==mxLen );
+    testcase( nBytes==mxLen+1 );
+    if( nBytes>mxLen ){
+      sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
+      (void)sqlite3SafetyOff(db);
+      rc = sqlite3ApiExit(db, SQLITE_TOOBIG);
+      goto end_prepare;
+    }
+    zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
+    if( zSqlCopy ){
+      sqlite3RunParser(pParse, zSqlCopy, &zErrMsg);
+      sqlite3DbFree(db, zSqlCopy);
+      pParse->zTail = &zSql[pParse->zTail-zSqlCopy];
+    }else{
+      pParse->zTail = &zSql[nBytes];
+    }
+  }else{
+    sqlite3RunParser(pParse, zSql, &zErrMsg);
+  }
+
+  if( db->mallocFailed ){
+    pParse->rc = SQLITE_NOMEM;
+  }
+  if( pParse->rc==SQLITE_DONE ) pParse->rc = SQLITE_OK;
+  if( pParse->checkSchema ){
+    schemaIsValid(pParse);
+  }
+  if( pParse->rc==SQLITE_SCHEMA ){
+    sqlite3ResetInternalSchema(db, 0);
+  }
+  if( db->mallocFailed ){
+    pParse->rc = SQLITE_NOMEM;
+  }
+  if( pzTail ){
+    *pzTail = pParse->zTail;
+  }
+  rc = pParse->rc;
+
+#ifndef SQLITE_OMIT_EXPLAIN
+  if( rc==SQLITE_OK && pParse->pVdbe && pParse->explain ){
+    static const char * const azColName[] = {
+       "addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment",
+       "order", "from", "detail"
+    };
+    int iFirst, mx;
+    if( pParse->explain==2 ){
+      sqlite3VdbeSetNumCols(pParse->pVdbe, 3);
+      iFirst = 8;
+      mx = 11;
+    }else{
+      sqlite3VdbeSetNumCols(pParse->pVdbe, 8);
+      iFirst = 0;
+      mx = 8;
+    }
+    for(i=iFirst; i<mx; i++){
+      sqlite3VdbeSetColName(pParse->pVdbe, i-iFirst, COLNAME_NAME,
+                            azColName[i], SQLITE_STATIC);
+    }
+  }
+#endif
+
+  if( sqlite3SafetyOff(db) ){
+    rc = SQLITE_MISUSE;
+  }
+
+  assert( db->init.busy==0 || saveSqlFlag==0 );
+  if( db->init.busy==0 ){
+    Vdbe *pVdbe = pParse->pVdbe;
+    sqlite3VdbeSetSql(pVdbe, zSql, (int)(pParse->zTail-zSql), saveSqlFlag);
+  }
+  if( pParse->pVdbe && (rc!=SQLITE_OK || db->mallocFailed) ){
+    sqlite3VdbeFinalize(pParse->pVdbe);
+    assert(!(*ppStmt));
+  }else{
+    *ppStmt = (sqlite3_stmt*)pParse->pVdbe;
+  }
+
+  if( zErrMsg ){
+    sqlite3Error(db, rc, "%s", zErrMsg);
+    sqlite3DbFree(db, zErrMsg);
+  }else{
+    sqlite3Error(db, rc, 0);
+  }
+
+  /* Delete any TriggerPrg structures allocated while parsing this statement. */
+  while( pParse->pTriggerPrg ){
+    TriggerPrg *pT = pParse->pTriggerPrg;
+    pParse->pTriggerPrg = pT->pNext;
+    sqlite3VdbeProgramDelete(db, pT->pProgram, 0);
+    sqlite3DbFree(db, pT);
+  }
+
+end_prepare:
+
+  sqlite3StackFree(db, pParse);
+  rc = sqlite3ApiExit(db, rc);
+  assert( (rc&db->errMask)==rc );
+  return rc;
+}
+static int sqlite3LockAndPrepare(
+  sqlite3 *db,              /* Database handle. */
+  const char *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  int saveSqlFlag,          /* True to copy SQL text into the sqlite3_stmt */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const char **pzTail       /* OUT: End of parsed string */
+){
+  int rc;
+  assert( ppStmt!=0 );
+  *ppStmt = 0;
+  if( !sqlite3SafetyCheckOk(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  sqlite3BtreeEnterAll(db);
+  rc = sqlite3Prepare(db, zSql, nBytes, saveSqlFlag, ppStmt, pzTail);
+  if( rc==SQLITE_SCHEMA ){
+    sqlite3_finalize(*ppStmt);
+    rc = sqlite3Prepare(db, zSql, nBytes, saveSqlFlag, ppStmt, pzTail);
+  }
+  sqlite3BtreeLeaveAll(db);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/*
+** Rerun the compilation of a statement after a schema change.
+**
+** If the statement is successfully recompiled, return SQLITE_OK. Otherwise,
+** if the statement cannot be recompiled because another connection has
+** locked the sqlite3_master table, return SQLITE_LOCKED. If any other error
+** occurs, return SQLITE_SCHEMA.
+*/
+SQLITE_PRIVATE int sqlite3Reprepare(Vdbe *p){
+  int rc;
+  sqlite3_stmt *pNew;
+  const char *zSql;
+  sqlite3 *db;
+
+  assert( sqlite3_mutex_held(sqlite3VdbeDb(p)->mutex) );
+  zSql = sqlite3_sql((sqlite3_stmt *)p);
+  assert( zSql!=0 );  /* Reprepare only called for prepare_v2() statements */
+  db = sqlite3VdbeDb(p);
+  assert( sqlite3_mutex_held(db->mutex) );
+  rc = sqlite3LockAndPrepare(db, zSql, -1, 0, &pNew, 0);
+  if( rc ){
+    if( rc==SQLITE_NOMEM ){
+      db->mallocFailed = 1;
+    }
+    assert( pNew==0 );
+    return (rc==SQLITE_LOCKED) ? SQLITE_LOCKED : SQLITE_SCHEMA;
+  }else{
+    assert( pNew!=0 );
+  }
+  sqlite3VdbeSwap((Vdbe*)pNew, p);
+  sqlite3TransferBindings(pNew, (sqlite3_stmt*)p);
+  sqlite3VdbeResetStepResult((Vdbe*)pNew);
+  sqlite3VdbeFinalize((Vdbe*)pNew);
+  return SQLITE_OK;
+}
+
+
+/*
+** Two versions of the official API.  Legacy and new use.  In the legacy
+** version, the original SQL text is not saved in the prepared statement
+** and so if a schema change occurs, SQLITE_SCHEMA is returned by
+** sqlite3_step().  In the new version, the original SQL text is retained
+** and the statement is automatically recompiled if an schema change
+** occurs.
+*/
+SQLITE_API int sqlite3_prepare(
+  sqlite3 *db,              /* Database handle. */
+  const char *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const char **pzTail       /* OUT: End of parsed string */
+){
+  int rc;
+  rc = sqlite3LockAndPrepare(db,zSql,nBytes,0,ppStmt,pzTail);
+  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
+  return rc;
+}
+SQLITE_API int sqlite3_prepare_v2(
+  sqlite3 *db,              /* Database handle. */
+  const char *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const char **pzTail       /* OUT: End of parsed string */
+){
+  int rc;
+  rc = sqlite3LockAndPrepare(db,zSql,nBytes,1,ppStmt,pzTail);
+  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
+  return rc;
+}
+
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Compile the UTF-16 encoded SQL statement zSql into a statement handle.
+*/
+static int sqlite3Prepare16(
+  sqlite3 *db,              /* Database handle. */ 
+  const void *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  int saveSqlFlag,          /* True to save SQL text into the sqlite3_stmt */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const void **pzTail       /* OUT: End of parsed string */
+){
+  /* This function currently works by first transforming the UTF-16
+  ** encoded string to UTF-8, then invoking sqlite3_prepare(). The
+  ** tricky bit is figuring out the pointer to return in *pzTail.
+  */
+  char *zSql8;
+  const char *zTail8 = 0;
+  int rc = SQLITE_OK;
+
+  assert( ppStmt );
+  *ppStmt = 0;
+  if( !sqlite3SafetyCheckOk(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  zSql8 = sqlite3Utf16to8(db, zSql, nBytes);
+  if( zSql8 ){
+    rc = sqlite3LockAndPrepare(db, zSql8, -1, saveSqlFlag, ppStmt, &zTail8);
+  }
+
+  if( zTail8 && pzTail ){
+    /* If sqlite3_prepare returns a tail pointer, we calculate the
+    ** equivalent pointer into the UTF-16 string by counting the unicode
+    ** characters between zSql8 and zTail8, and then returning a pointer
+    ** the same number of characters into the UTF-16 string.
+    */
+    int chars_parsed = sqlite3Utf8CharLen(zSql8, (int)(zTail8-zSql8));
+    *pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
+  }
+  sqlite3DbFree(db, zSql8); 
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/*
+** Two versions of the official API.  Legacy and new use.  In the legacy
+** version, the original SQL text is not saved in the prepared statement
+** and so if a schema change occurs, SQLITE_SCHEMA is returned by
+** sqlite3_step().  In the new version, the original SQL text is retained
+** and the statement is automatically recompiled if an schema change
+** occurs.
+*/
+SQLITE_API int sqlite3_prepare16(
+  sqlite3 *db,              /* Database handle. */ 
+  const void *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const void **pzTail       /* OUT: End of parsed string */
+){
+  int rc;
+  rc = sqlite3Prepare16(db,zSql,nBytes,0,ppStmt,pzTail);
+  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
+  return rc;
+}
+SQLITE_API int sqlite3_prepare16_v2(
+  sqlite3 *db,              /* Database handle. */ 
+  const void *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const void **pzTail       /* OUT: End of parsed string */
+){
+  int rc;
+  rc = sqlite3Prepare16(db,zSql,nBytes,1,ppStmt,pzTail);
+  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
+  return rc;
+}
+
+#endif /* SQLITE_OMIT_UTF16 */
+
+/************** End of prepare.c *********************************************/
+/************** Begin file select.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that are called by the parser
+** to handle SELECT statements in SQLite.
+**
+** $Id: select.c,v 1.526 2009/08/01 15:09:58 drh Exp $
+*/
+
+
+/*
+** Delete all the content of a Select structure but do not deallocate
+** the select structure itself.
+*/
+static void clearSelect(sqlite3 *db, Select *p){
+  sqlite3ExprListDelete(db, p->pEList);
+  sqlite3SrcListDelete(db, p->pSrc);
+  sqlite3ExprDelete(db, p->pWhere);
+  sqlite3ExprListDelete(db, p->pGroupBy);
+  sqlite3ExprDelete(db, p->pHaving);
+  sqlite3ExprListDelete(db, p->pOrderBy);
+  sqlite3SelectDelete(db, p->pPrior);
+  sqlite3ExprDelete(db, p->pLimit);
+  sqlite3ExprDelete(db, p->pOffset);
+}
+
+/*
+** Initialize a SelectDest structure.
+*/
+SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
+  pDest->eDest = (u8)eDest;
+  pDest->iParm = iParm;
+  pDest->affinity = 0;
+  pDest->iMem = 0;
+  pDest->nMem = 0;
+}
+
+
+/*
+** Allocate a new Select structure and return a pointer to that
+** structure.
+*/
+SQLITE_PRIVATE Select *sqlite3SelectNew(
+  Parse *pParse,        /* Parsing context */
+  ExprList *pEList,     /* which columns to include in the result */
+  SrcList *pSrc,        /* the FROM clause -- which tables to scan */
+  Expr *pWhere,         /* the WHERE clause */
+  ExprList *pGroupBy,   /* the GROUP BY clause */
+  Expr *pHaving,        /* the HAVING clause */
+  ExprList *pOrderBy,   /* the ORDER BY clause */
+  int isDistinct,       /* true if the DISTINCT keyword is present */
+  Expr *pLimit,         /* LIMIT value.  NULL means not used */
+  Expr *pOffset         /* OFFSET value.  NULL means no offset */
+){
+  Select *pNew;
+  Select standin;
+  sqlite3 *db = pParse->db;
+  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) );
+  assert( db->mallocFailed || !pOffset || pLimit ); /* OFFSET implies LIMIT */
+  if( pNew==0 ){
+    pNew = &standin;
+    memset(pNew, 0, sizeof(*pNew));
+  }
+  if( pEList==0 ){
+    pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db,TK_ALL,0));
+  }
+  pNew->pEList = pEList;
+  pNew->pSrc = pSrc;
+  pNew->pWhere = pWhere;
+  pNew->pGroupBy = pGroupBy;
+  pNew->pHaving = pHaving;
+  pNew->pOrderBy = pOrderBy;
+  pNew->selFlags = isDistinct ? SF_Distinct : 0;
+  pNew->op = TK_SELECT;
+  pNew->pLimit = pLimit;
+  pNew->pOffset = pOffset;
+  assert( pOffset==0 || pLimit!=0 );
+  pNew->addrOpenEphm[0] = -1;
+  pNew->addrOpenEphm[1] = -1;
+  pNew->addrOpenEphm[2] = -1;
+  if( db->mallocFailed ) {
+    clearSelect(db, pNew);
+    if( pNew!=&standin ) sqlite3DbFree(db, pNew);
+    pNew = 0;
+  }
+  return pNew;
+}
+
+/*
+** Delete the given Select structure and all of its substructures.
+*/
+SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3 *db, Select *p){
+  if( p ){
+    clearSelect(db, p);
+    sqlite3DbFree(db, p);
+  }
+}
+
+/*
+** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
+** type of join.  Return an integer constant that expresses that type
+** in terms of the following bit values:
+**
+**     JT_INNER
+**     JT_CROSS
+**     JT_OUTER
+**     JT_NATURAL
+**     JT_LEFT
+**     JT_RIGHT
+**
+** A full outer join is the combination of JT_LEFT and JT_RIGHT.
+**
+** If an illegal or unsupported join type is seen, then still return
+** a join type, but put an error in the pParse structure.
+*/
+SQLITE_PRIVATE int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){
+  int jointype = 0;
+  Token *apAll[3];
+  Token *p;
+                             /*   0123456789 123456789 123456789 123 */
+  static const char zKeyText[] = "naturaleftouterightfullinnercross";
+  static const struct {
+    u8 i;        /* Beginning of keyword text in zKeyText[] */
+    u8 nChar;    /* Length of the keyword in characters */
+    u8 code;     /* Join type mask */
+  } aKeyword[] = {
+    /* natural */ { 0,  7, JT_NATURAL                },
+    /* left    */ { 6,  4, JT_LEFT|JT_OUTER          },
+    /* outer   */ { 10, 5, JT_OUTER                  },
+    /* right   */ { 14, 5, JT_RIGHT|JT_OUTER         },
+    /* full    */ { 19, 4, JT_LEFT|JT_RIGHT|JT_OUTER },
+    /* inner   */ { 23, 5, JT_INNER                  },
+    /* cross   */ { 28, 5, JT_INNER|JT_CROSS         },
+  };
+  int i, j;
+  apAll[0] = pA;
+  apAll[1] = pB;
+  apAll[2] = pC;
+  for(i=0; i<3 && apAll[i]; i++){
+    p = apAll[i];
+    for(j=0; j<ArraySize(aKeyword); j++){
+      if( p->n==aKeyword[j].nChar 
+          && sqlite3StrNICmp((char*)p->z, &zKeyText[aKeyword[j].i], p->n)==0 ){
+        jointype |= aKeyword[j].code;
+        break;
+      }
+    }
+    testcase( j==0 || j==1 || j==2 || j==3 || j==4 || j==5 || j==6 );
+    if( j>=ArraySize(aKeyword) ){
+      jointype |= JT_ERROR;
+      break;
+    }
+  }
+  if(
+     (jointype & (JT_INNER|JT_OUTER))==(JT_INNER|JT_OUTER) ||
+     (jointype & JT_ERROR)!=0
+  ){
+    const char *zSp = " ";
+    assert( pB!=0 );
+    if( pC==0 ){ zSp++; }
+    sqlite3ErrorMsg(pParse, "unknown or unsupported join type: "
+       "%T %T%s%T", pA, pB, zSp, pC);
+    jointype = JT_INNER;
+  }else if( (jointype & JT_OUTER)!=0 
+         && (jointype & (JT_LEFT|JT_RIGHT))!=JT_LEFT ){
+    sqlite3ErrorMsg(pParse, 
+      "RIGHT and FULL OUTER JOINs are not currently supported");
+    jointype = JT_INNER;
+  }
+  return jointype;
+}
+
+/*
+** Return the index of a column in a table.  Return -1 if the column
+** is not contained in the table.
+*/
+static int columnIndex(Table *pTab, const char *zCol){
+  int i;
+  for(i=0; i<pTab->nCol; i++){
+    if( sqlite3StrICmp(pTab->aCol[i].zName, zCol)==0 ) return i;
+  }
+  return -1;
+}
+
+/*
+** Create an expression node for an identifier with the name of zName
+*/
+SQLITE_PRIVATE Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){
+  return sqlite3Expr(pParse->db, TK_ID, zName);
+}
+
+/*
+** Add a term to the WHERE expression in *ppExpr that requires the
+** zCol column to be equal in the two tables pTab1 and pTab2.
+*/
+static void addWhereTerm(
+  Parse *pParse,           /* Parsing context */
+  const char *zCol,        /* Name of the column */
+  const Table *pTab1,      /* First table */
+  const char *zAlias1,     /* Alias for first table.  May be NULL */
+  const Table *pTab2,      /* Second table */
+  const char *zAlias2,     /* Alias for second table.  May be NULL */
+  int iRightJoinTable,     /* VDBE cursor for the right table */
+  Expr **ppExpr,           /* Add the equality term to this expression */
+  int isOuterJoin          /* True if dealing with an OUTER join */
+){
+  Expr *pE1a, *pE1b, *pE1c;
+  Expr *pE2a, *pE2b, *pE2c;
+  Expr *pE;
+
+  pE1a = sqlite3CreateIdExpr(pParse, zCol);
+  pE2a = sqlite3CreateIdExpr(pParse, zCol);
+  if( zAlias1==0 ){
+    zAlias1 = pTab1->zName;
+  }
+  pE1b = sqlite3CreateIdExpr(pParse, zAlias1);
+  if( zAlias2==0 ){
+    zAlias2 = pTab2->zName;
+  }
+  pE2b = sqlite3CreateIdExpr(pParse, zAlias2);
+  pE1c = sqlite3PExpr(pParse, TK_DOT, pE1b, pE1a, 0);
+  pE2c = sqlite3PExpr(pParse, TK_DOT, pE2b, pE2a, 0);
+  pE = sqlite3PExpr(pParse, TK_EQ, pE1c, pE2c, 0);
+  if( pE && isOuterJoin ){
+    ExprSetProperty(pE, EP_FromJoin);
+    assert( !ExprHasAnyProperty(pE, EP_TokenOnly|EP_Reduced) );
+    ExprSetIrreducible(pE);
+    pE->iRightJoinTable = (i16)iRightJoinTable;
+  }
+  *ppExpr = sqlite3ExprAnd(pParse->db,*ppExpr, pE);
+}
+
+/*
+** Set the EP_FromJoin property on all terms of the given expression.
+** And set the Expr.iRightJoinTable to iTable for every term in the
+** expression.
+**
+** The EP_FromJoin property is used on terms of an expression to tell
+** the LEFT OUTER JOIN processing logic that this term is part of the
+** join restriction specified in the ON or USING clause and not a part
+** of the more general WHERE clause.  These terms are moved over to the
+** WHERE clause during join processing but we need to remember that they
+** originated in the ON or USING clause.
+**
+** The Expr.iRightJoinTable tells the WHERE clause processing that the
+** expression depends on table iRightJoinTable even if that table is not
+** explicitly mentioned in the expression.  That information is needed
+** for cases like this:
+**
+**    SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.b AND t1.x=5
+**
+** The where clause needs to defer the handling of the t1.x=5
+** term until after the t2 loop of the join.  In that way, a
+** NULL t2 row will be inserted whenever t1.x!=5.  If we do not
+** defer the handling of t1.x=5, it will be processed immediately
+** after the t1 loop and rows with t1.x!=5 will never appear in
+** the output, which is incorrect.
+*/
+static void setJoinExpr(Expr *p, int iTable){
+  while( p ){
+    ExprSetProperty(p, EP_FromJoin);
+    assert( !ExprHasAnyProperty(p, EP_TokenOnly|EP_Reduced) );
+    ExprSetIrreducible(p);
+    p->iRightJoinTable = (i16)iTable;
+    setJoinExpr(p->pLeft, iTable);
+    p = p->pRight;
+  } 
+}
 
-#ifdef SQLITE_OMIT_AUTHORIZATION
-# define sqlite3_set_authorizer         0
-#endif
+/*
+** This routine processes the join information for a SELECT statement.
+** ON and USING clauses are converted into extra terms of the WHERE clause.
+** NATURAL joins also create extra WHERE clause terms.
+**
+** The terms of a FROM clause are contained in the Select.pSrc structure.
+** The left most table is the first entry in Select.pSrc.  The right-most
+** table is the last entry.  The join operator is held in the entry to
+** the left.  Thus entry 0 contains the join operator for the join between
+** entries 0 and 1.  Any ON or USING clauses associated with the join are
+** also attached to the left entry.
+**
+** This routine returns the number of errors encountered.
+*/
+static int sqliteProcessJoin(Parse *pParse, Select *p){
+  SrcList *pSrc;                  /* All tables in the FROM clause */
+  int i, j;                       /* Loop counters */
+  struct SrcList_item *pLeft;     /* Left table being joined */
+  struct SrcList_item *pRight;    /* Right table being joined */
 
-#ifdef SQLITE_OMIT_UTF16
-# define sqlite3_bind_text16            0
-# define sqlite3_collation_needed16     0
-# define sqlite3_column_decltype16      0
-# define sqlite3_column_name16          0
-# define sqlite3_column_text16          0
-# define sqlite3_complete16             0
-# define sqlite3_create_collation16     0
-# define sqlite3_create_function16      0
-# define sqlite3_errmsg16               0
-# define sqlite3_open16                 0
-# define sqlite3_prepare16              0
-# define sqlite3_prepare16_v2           0
-# define sqlite3_result_error16         0
-# define sqlite3_result_text16          0
-# define sqlite3_result_text16be        0
-# define sqlite3_result_text16le        0
-# define sqlite3_value_text16           0
-# define sqlite3_value_text16be         0
-# define sqlite3_value_text16le         0
-# define sqlite3_column_database_name16 0
-# define sqlite3_column_table_name16    0
-# define sqlite3_column_origin_name16   0
-#endif
+  pSrc = p->pSrc;
+  pLeft = &pSrc->a[0];
+  pRight = &pLeft[1];
+  for(i=0; i<pSrc->nSrc-1; i++, pRight++, pLeft++){
+    Table *pLeftTab = pLeft->pTab;
+    Table *pRightTab = pRight->pTab;
+    int isOuter;
 
-#ifdef SQLITE_OMIT_COMPLETE
-# define sqlite3_complete 0
-# define sqlite3_complete16 0
-#endif
+    if( NEVER(pLeftTab==0 || pRightTab==0) ) continue;
+    isOuter = (pRight->jointype & JT_OUTER)!=0;
 
-#ifdef SQLITE_OMIT_PROGRESS_CALLBACK
-# define sqlite3_progress_handler 0
-#endif
+    /* When the NATURAL keyword is present, add WHERE clause terms for
+    ** every column that the two tables have in common.
+    */
+    if( pRight->jointype & JT_NATURAL ){
+      if( pRight->pOn || pRight->pUsing ){
+        sqlite3ErrorMsg(pParse, "a NATURAL join may not have "
+           "an ON or USING clause", 0);
+        return 1;
+      }
+      for(j=0; j<pLeftTab->nCol; j++){
+        char *zName = pLeftTab->aCol[j].zName;
+        if( columnIndex(pRightTab, zName)>=0 ){
+          addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
+                              pRightTab, pRight->zAlias,
+                              pRight->iCursor, &p->pWhere, isOuter);
+          
+        }
+      }
+    }
 
-#ifdef SQLITE_OMIT_VIRTUALTABLE
-# define sqlite3_create_module 0
-# define sqlite3_create_module_v2 0
-# define sqlite3_declare_vtab 0
-#endif
+    /* Disallow both ON and USING clauses in the same join
+    */
+    if( pRight->pOn && pRight->pUsing ){
+      sqlite3ErrorMsg(pParse, "cannot have both ON and USING "
+        "clauses in the same join");
+      return 1;
+    }
 
-#ifdef SQLITE_OMIT_SHARED_CACHE
-# define sqlite3_enable_shared_cache 0
-#endif
+    /* Add the ON clause to the end of the WHERE clause, connected by
+    ** an AND operator.
+    */
+    if( pRight->pOn ){
+      if( isOuter ) setJoinExpr(pRight->pOn, pRight->iCursor);
+      p->pWhere = sqlite3ExprAnd(pParse->db, p->pWhere, pRight->pOn);
+      pRight->pOn = 0;
+    }
 
-#ifdef SQLITE_OMIT_TRACE
-# define sqlite3_profile       0
-# define sqlite3_trace         0
-#endif
+    /* Create extra terms on the WHERE clause for each column named
+    ** in the USING clause.  Example: If the two tables to be joined are 
+    ** A and B and the USING clause names X, Y, and Z, then add this
+    ** to the WHERE clause:    A.X=B.X AND A.Y=B.Y AND A.Z=B.Z
+    ** Report an error if any column mentioned in the USING clause is
+    ** not contained in both tables to be joined.
+    */
+    if( pRight->pUsing ){
+      IdList *pList = pRight->pUsing;
+      for(j=0; j<pList->nId; j++){
+        char *zName = pList->a[j].zName;
+        if( columnIndex(pLeftTab, zName)<0 || columnIndex(pRightTab, zName)<0 ){
+          sqlite3ErrorMsg(pParse, "cannot join using column %s - column "
+            "not present in both tables", zName);
+          return 1;
+        }
+        addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
+                            pRightTab, pRight->zAlias,
+                            pRight->iCursor, &p->pWhere, isOuter);
+      }
+    }
+  }
+  return 0;
+}
 
-#ifdef SQLITE_OMIT_GET_TABLE
-# define sqlite3_free_table    0
-# define sqlite3_get_table     0
-#endif
+/*
+** Insert code into "v" that will push the record on the top of the
+** stack into the sorter.
+*/
+static void pushOntoSorter(
+  Parse *pParse,         /* Parser context */
+  ExprList *pOrderBy,    /* The ORDER BY clause */
+  Select *pSelect,       /* The whole SELECT statement */
+  int regData            /* Register holding data to be sorted */
+){
+  Vdbe *v = pParse->pVdbe;
+  int nExpr = pOrderBy->nExpr;
+  int regBase = sqlite3GetTempRange(pParse, nExpr+2);
+  int regRecord = sqlite3GetTempReg(pParse);
+  sqlite3ExprCacheClear(pParse);
+  sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0);
+  sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr);
+  sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1, 1);
+  sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nExpr + 2, regRecord);
+  sqlite3VdbeAddOp2(v, OP_IdxInsert, pOrderBy->iECursor, regRecord);
+  sqlite3ReleaseTempReg(pParse, regRecord);
+  sqlite3ReleaseTempRange(pParse, regBase, nExpr+2);
+  if( pSelect->iLimit ){
+    int addr1, addr2;
+    int iLimit;
+    if( pSelect->iOffset ){
+      iLimit = pSelect->iOffset+1;
+    }else{
+      iLimit = pSelect->iLimit;
+    }
+    addr1 = sqlite3VdbeAddOp1(v, OP_IfZero, iLimit);
+    sqlite3VdbeAddOp2(v, OP_AddImm, iLimit, -1);
+    addr2 = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, addr1);
+    sqlite3VdbeAddOp1(v, OP_Last, pOrderBy->iECursor);
+    sqlite3VdbeAddOp1(v, OP_Delete, pOrderBy->iECursor);
+    sqlite3VdbeJumpHere(v, addr2);
+    pSelect->iLimit = 0;
+  }
+}
 
-#ifdef SQLITE_OMIT_INCRBLOB
-#define sqlite3_bind_zeroblob  0
-#define sqlite3_blob_bytes     0
-#define sqlite3_blob_close     0
-#define sqlite3_blob_open      0
-#define sqlite3_blob_read      0
-#define sqlite3_blob_write     0
-#endif
+/*
+** Add code to implement the OFFSET
+*/
+static void codeOffset(
+  Vdbe *v,          /* Generate code into this VM */
+  Select *p,        /* The SELECT statement being coded */
+  int iContinue     /* Jump here to skip the current record */
+){
+  if( p->iOffset && iContinue!=0 ){
+    int addr;
+    sqlite3VdbeAddOp2(v, OP_AddImm, p->iOffset, -1);
+    addr = sqlite3VdbeAddOp1(v, OP_IfNeg, p->iOffset);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, iContinue);
+    VdbeComment((v, "skip OFFSET records"));
+    sqlite3VdbeJumpHere(v, addr);
+  }
+}
 
 /*
-** The following structure contains pointers to all SQLite API routines.
-** A pointer to this structure is passed into extensions when they are
-** loaded so that the extension can make calls back into the SQLite
-** library.
-**
-** When adding new APIs, add them to the bottom of this structure
-** in order to preserve backwards compatibility.
+** Add code that will check to make sure the N registers starting at iMem
+** form a distinct entry.  iTab is a sorting index that holds previously
+** seen combinations of the N values.  A new entry is made in iTab
+** if the current N values are new.
 **
-** Extensions that use newer APIs should first call the
-** sqlite3_libversion_number() to make sure that the API they
-** intend to use is supported by the library.  Extensions should
-** also check to make sure that the pointer to the function is
-** not NULL before calling it.
+** A jump to addrRepeat is made and the N+1 values are popped from the
+** stack if the top N elements are not distinct.
 */
-static const sqlite3_api_routines sqlite3Apis = {
-  sqlite3_aggregate_context,
-  sqlite3_aggregate_count,
-  sqlite3_bind_blob,
-  sqlite3_bind_double,
-  sqlite3_bind_int,
-  sqlite3_bind_int64,
-  sqlite3_bind_null,
-  sqlite3_bind_parameter_count,
-  sqlite3_bind_parameter_index,
-  sqlite3_bind_parameter_name,
-  sqlite3_bind_text,
-  sqlite3_bind_text16,
-  sqlite3_bind_value,
-  sqlite3_busy_handler,
-  sqlite3_busy_timeout,
-  sqlite3_changes,
-  sqlite3_close,
-  sqlite3_collation_needed,
-  sqlite3_collation_needed16,
-  sqlite3_column_blob,
-  sqlite3_column_bytes,
-  sqlite3_column_bytes16,
-  sqlite3_column_count,
-  sqlite3_column_database_name,
-  sqlite3_column_database_name16,
-  sqlite3_column_decltype,
-  sqlite3_column_decltype16,
-  sqlite3_column_double,
-  sqlite3_column_int,
-  sqlite3_column_int64,
-  sqlite3_column_name,
-  sqlite3_column_name16,
-  sqlite3_column_origin_name,
-  sqlite3_column_origin_name16,
-  sqlite3_column_table_name,
-  sqlite3_column_table_name16,
-  sqlite3_column_text,
-  sqlite3_column_text16,
-  sqlite3_column_type,
-  sqlite3_column_value,
-  sqlite3_commit_hook,
-  sqlite3_complete,
-  sqlite3_complete16,
-  sqlite3_create_collation,
-  sqlite3_create_collation16,
-  sqlite3_create_function,
-  sqlite3_create_function16,
-  sqlite3_create_module,
-  sqlite3_data_count,
-  sqlite3_db_handle,
-  sqlite3_declare_vtab,
-  sqlite3_enable_shared_cache,
-  sqlite3_errcode,
-  sqlite3_errmsg,
-  sqlite3_errmsg16,
-  sqlite3_exec,
-  sqlite3_expired,
-  sqlite3_finalize,
-  sqlite3_free,
-  sqlite3_free_table,
-  sqlite3_get_autocommit,
-  sqlite3_get_auxdata,
-  sqlite3_get_table,
-  0,     /* Was sqlite3_global_recover(), but that function is deprecated */
-  sqlite3_interrupt,
-  sqlite3_last_insert_rowid,
-  sqlite3_libversion,
-  sqlite3_libversion_number,
-  sqlite3_malloc,
-  sqlite3_mprintf,
-  sqlite3_open,
-  sqlite3_open16,
-  sqlite3_prepare,
-  sqlite3_prepare16,
-  sqlite3_profile,
-  sqlite3_progress_handler,
-  sqlite3_realloc,
-  sqlite3_reset,
-  sqlite3_result_blob,
-  sqlite3_result_double,
-  sqlite3_result_error,
-  sqlite3_result_error16,
-  sqlite3_result_int,
-  sqlite3_result_int64,
-  sqlite3_result_null,
-  sqlite3_result_text,
-  sqlite3_result_text16,
-  sqlite3_result_text16be,
-  sqlite3_result_text16le,
-  sqlite3_result_value,
-  sqlite3_rollback_hook,
-  sqlite3_set_authorizer,
-  sqlite3_set_auxdata,
-  sqlite3_snprintf,
-  sqlite3_step,
-  sqlite3_table_column_metadata,
-  sqlite3_thread_cleanup,
-  sqlite3_total_changes,
-  sqlite3_trace,
-  sqlite3_transfer_bindings,
-  sqlite3_update_hook,
-  sqlite3_user_data,
-  sqlite3_value_blob,
-  sqlite3_value_bytes,
-  sqlite3_value_bytes16,
-  sqlite3_value_double,
-  sqlite3_value_int,
-  sqlite3_value_int64,
-  sqlite3_value_numeric_type,
-  sqlite3_value_text,
-  sqlite3_value_text16,
-  sqlite3_value_text16be,
-  sqlite3_value_text16le,
-  sqlite3_value_type,
-  sqlite3_vmprintf,
-  /*
-  ** The original API set ends here.  All extensions can call any
-  ** of the APIs above provided that the pointer is not NULL.  But
-  ** before calling APIs that follow, extension should check the
-  ** sqlite3_libversion_number() to make sure they are dealing with
-  ** a library that is new enough to support that API.
-  *************************************************************************
-  */
-  sqlite3_overload_function,
-
-  /*
-  ** Added after 3.3.13
-  */
-  sqlite3_prepare_v2,
-  sqlite3_prepare16_v2,
-  sqlite3_clear_bindings,
-
-  /*
-  ** Added for 3.4.1
-  */
-  sqlite3_create_module_v2,
+static void codeDistinct(
+  Parse *pParse,     /* Parsing and code generating context */
+  int iTab,          /* A sorting index used to test for distinctness */
+  int addrRepeat,    /* Jump to here if not distinct */
+  int N,             /* Number of elements */
+  int iMem           /* First element */
+){
+  Vdbe *v;
+  int r1;
 
-  /*
-  ** Added for 3.5.0
-  */
-  sqlite3_bind_zeroblob,
-  sqlite3_blob_bytes,
-  sqlite3_blob_close,
-  sqlite3_blob_open,
-  sqlite3_blob_read,
-  sqlite3_blob_write,
-  sqlite3_create_collation_v2,
-  sqlite3_file_control,
-  sqlite3_memory_highwater,
-  sqlite3_memory_used,
-#ifdef SQLITE_MUTEX_NOOP
-  0, 
-  0, 
-  0,
-  0,
-  0,
-#else
-  sqlite3_mutex_alloc,
-  sqlite3_mutex_enter,
-  sqlite3_mutex_free,
-  sqlite3_mutex_leave,
-  sqlite3_mutex_try,
-#endif
-  sqlite3_open_v2,
-  sqlite3_release_memory,
-  sqlite3_result_error_nomem,
-  sqlite3_result_error_toobig,
-  sqlite3_sleep,
-  sqlite3_soft_heap_limit,
-  sqlite3_vfs_find,
-  sqlite3_vfs_register,
-  sqlite3_vfs_unregister,
+  v = pParse->pVdbe;
+  r1 = sqlite3GetTempReg(pParse);
+  sqlite3VdbeAddOp3(v, OP_MakeRecord, iMem, N, r1);
+  sqlite3VdbeAddOp3(v, OP_Found, iTab, addrRepeat, r1);
+  sqlite3VdbeAddOp2(v, OP_IdxInsert, iTab, r1);
+  sqlite3ReleaseTempReg(pParse, r1);
+}
 
-  /*
-  ** Added for 3.5.8
-  */
-  sqlite3_threadsafe,
-  sqlite3_result_zeroblob,
-  sqlite3_result_error_code,
-  sqlite3_test_control,
-  sqlite3_randomness,
-  sqlite3_context_db_handle,
-};
+/*
+** Generate an error message when a SELECT is used within a subexpression
+** (example:  "a IN (SELECT * FROM table)") but it has more than 1 result
+** column.  We do this in a subroutine because the error occurs in multiple
+** places.
+*/
+static int checkForMultiColumnSelectError(
+  Parse *pParse,       /* Parse context. */
+  SelectDest *pDest,   /* Destination of SELECT results */
+  int nExpr            /* Number of result columns returned by SELECT */
+){
+  int eDest = pDest->eDest;
+  if( nExpr>1 && (eDest==SRT_Mem || eDest==SRT_Set) ){
+    sqlite3ErrorMsg(pParse, "only a single result allowed for "
+       "a SELECT that is part of an expression");
+    return 1;
+  }else{
+    return 0;
+  }
+}
 
 /*
-** Attempt to load an SQLite extension library contained in the file
-** zFile.  The entry point is zProc.  zProc may be 0 in which case a
-** default entry point name (sqlite3_extension_init) is used.  Use
-** of the default name is recommended.
-**
-** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
+** This routine generates the code for the inside of the inner loop
+** of a SELECT.
 **
-** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 
-** error message text.  The calling function should free this memory
-** by calling sqlite3_free().
+** If srcTab and nColumn are both zero, then the pEList expressions
+** are evaluated in order to get the data for this row.  If nColumn>0
+** then data is pulled from srcTab and pEList is used only to get the
+** datatypes for each column.
 */
-static int sqlite3LoadExtension(
-  sqlite3 *db,          /* Load the extension into this database connection */
-  const char *zFile,    /* Name of the shared library containing extension */
-  const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
-  char **pzErrMsg       /* Put error message here if not 0 */
+static void selectInnerLoop(
+  Parse *pParse,          /* The parser context */
+  Select *p,              /* The complete select statement being coded */
+  ExprList *pEList,       /* List of values being extracted */
+  int srcTab,             /* Pull data from this table */
+  int nColumn,            /* Number of columns in the source table */
+  ExprList *pOrderBy,     /* If not NULL, sort results using this key */
+  int distinct,           /* If >=0, make sure results are distinct */
+  SelectDest *pDest,      /* How to dispose of the results */
+  int iContinue,          /* Jump here to continue with next row */
+  int iBreak              /* Jump here to break out of the inner loop */
 ){
-  sqlite3_vfs *pVfs = db->pVfs;
-  void *handle;
-  int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
-  char *zErrmsg = 0;
-  void **aHandle;
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  int hasDistinct;        /* True if the DISTINCT keyword is present */
+  int regResult;              /* Start of memory holding result set */
+  int eDest = pDest->eDest;   /* How to dispose of results */
+  int iParm = pDest->iParm;   /* First argument to disposal method */
+  int nResultCol;             /* Number of result columns */
 
-  /* Ticket #1863.  To avoid a creating security problems for older
-  ** applications that relink against newer versions of SQLite, the
-  ** ability to run load_extension is turned off by default.  One
-  ** must call sqlite3_enable_load_extension() to turn on extension
-  ** loading.  Otherwise you get the following error.
+  assert( v );
+  if( NEVER(v==0) ) return;
+  assert( pEList!=0 );
+  hasDistinct = distinct>=0;
+  if( pOrderBy==0 && !hasDistinct ){
+    codeOffset(v, p, iContinue);
+  }
+
+  /* Pull the requested columns.
+  */
+  if( nColumn>0 ){
+    nResultCol = nColumn;
+  }else{
+    nResultCol = pEList->nExpr;
+  }
+  if( pDest->iMem==0 ){
+    pDest->iMem = pParse->nMem+1;
+    pDest->nMem = nResultCol;
+    pParse->nMem += nResultCol;
+  }else{ 
+    assert( pDest->nMem==nResultCol );
+  }
+  regResult = pDest->iMem;
+  if( nColumn>0 ){
+    for(i=0; i<nColumn; i++){
+      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
+    }
+  }else if( eDest!=SRT_Exists ){
+    /* If the destination is an EXISTS(...) expression, the actual
+    ** values returned by the SELECT are not required.
+    */
+    sqlite3ExprCacheClear(pParse);
+    sqlite3ExprCodeExprList(pParse, pEList, regResult, eDest==SRT_Output);
+  }
+  nColumn = nResultCol;
+
+  /* If the DISTINCT keyword was present on the SELECT statement
+  ** and this row has been seen before, then do not make this row
+  ** part of the result.
   */
-  if( (db->flags & SQLITE_LoadExtension)==0 ){
-    if( pzErrMsg ){
-      *pzErrMsg = sqlite3_mprintf("not authorized");
+  if( hasDistinct ){
+    assert( pEList!=0 );
+    assert( pEList->nExpr==nColumn );
+    codeDistinct(pParse, distinct, iContinue, nColumn, regResult);
+    if( pOrderBy==0 ){
+      codeOffset(v, p, iContinue);
     }
-    return SQLITE_ERROR;
   }
 
-  if( zProc==0 ){
-    zProc = "sqlite3_extension_init";
+  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
+    return;
   }
 
-  handle = sqlite3OsDlOpen(pVfs, zFile);
-  if( handle==0 ){
-    if( pzErrMsg ){
-      char zErr[256];
-      zErr[sizeof(zErr)-1] = '\0';
-      sqlite3_snprintf(sizeof(zErr)-1, zErr, 
-          "unable to open shared library [%s]", zFile);
-      sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);
-      *pzErrMsg = sqlite3DbStrDup(db, zErr);
+  switch( eDest ){
+    /* In this mode, write each query result to the key of the temporary
+    ** table iParm.
+    */
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
+    case SRT_Union: {
+      int r1;
+      r1 = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
+      sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
     }
-    return SQLITE_ERROR;
-  }
-  xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
-                   sqlite3OsDlSym(pVfs, handle, zProc);
-  if( xInit==0 ){
-    if( pzErrMsg ){
-      char zErr[256];
-      zErr[sizeof(zErr)-1] = '\0';
-      sqlite3_snprintf(sizeof(zErr)-1, zErr,
-          "no entry point [%s] in shared library [%s]", zProc,zFile);
-      sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);
-      *pzErrMsg = sqlite3DbStrDup(db, zErr);
-      sqlite3OsDlClose(pVfs, handle);
+
+    /* Construct a record from the query result, but instead of
+    ** saving that record, use it as a key to delete elements from
+    ** the temporary table iParm.
+    */
+    case SRT_Except: {
+      sqlite3VdbeAddOp3(v, OP_IdxDelete, iParm, regResult, nColumn);
+      break;
     }
-    return SQLITE_ERROR;
-  }else if( xInit(db, &zErrmsg, &sqlite3Apis) ){
-    if( pzErrMsg ){
-      *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
+#endif
+
+    /* Store the result as data using a unique key.
+    */
+    case SRT_Table:
+    case SRT_EphemTab: {
+      int r1 = sqlite3GetTempReg(pParse);
+      testcase( eDest==SRT_Table );
+      testcase( eDest==SRT_EphemTab );
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
+      if( pOrderBy ){
+        pushOntoSorter(pParse, pOrderBy, p, r1);
+      }else{
+        int r2 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, r2);
+        sqlite3VdbeAddOp3(v, OP_Insert, iParm, r1, r2);
+        sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+        sqlite3ReleaseTempReg(pParse, r2);
+      }
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
     }
-    sqlite3_free(zErrmsg);
-    sqlite3OsDlClose(pVfs, handle);
-    return SQLITE_ERROR;
-  }
 
-  /* Append the new shared library handle to the db->aExtension array. */
-  db->nExtension++;
-  aHandle = sqlite3DbMallocZero(db, sizeof(handle)*db->nExtension);
-  if( aHandle==0 ){
-    return SQLITE_NOMEM;
-  }
-  if( db->nExtension>0 ){
-    memcpy(aHandle, db->aExtension, sizeof(handle)*(db->nExtension-1));
+#ifndef SQLITE_OMIT_SUBQUERY
+    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
+    ** then there should be a single item on the stack.  Write this
+    ** item into the set table with bogus data.
+    */
+    case SRT_Set: {
+      assert( nColumn==1 );
+      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
+      if( pOrderBy ){
+        /* At first glance you would think we could optimize out the
+        ** ORDER BY in this case since the order of entries in the set
+        ** does not matter.  But there might be a LIMIT clause, in which
+        ** case the order does matter */
+        pushOntoSorter(pParse, pOrderBy, p, regResult);
+      }else{
+        int r1 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, 1, r1, &p->affinity, 1);
+        sqlite3ExprCacheAffinityChange(pParse, regResult, 1);
+        sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
+        sqlite3ReleaseTempReg(pParse, r1);
+      }
+      break;
+    }
+
+    /* If any row exist in the result set, record that fact and abort.
+    */
+    case SRT_Exists: {
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iParm);
+      /* The LIMIT clause will terminate the loop for us */
+      break;
+    }
+
+    /* If this is a scalar select that is part of an expression, then
+    ** store the results in the appropriate memory cell and break out
+    ** of the scan loop.
+    */
+    case SRT_Mem: {
+      assert( nColumn==1 );
+      if( pOrderBy ){
+        pushOntoSorter(pParse, pOrderBy, p, regResult);
+      }else{
+        sqlite3ExprCodeMove(pParse, regResult, iParm, 1);
+        /* The LIMIT clause will jump out of the loop for us */
+      }
+      break;
+    }
+#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
+
+    /* Send the data to the callback function or to a subroutine.  In the
+    ** case of a subroutine, the subroutine itself is responsible for
+    ** popping the data from the stack.
+    */
+    case SRT_Coroutine:
+    case SRT_Output: {
+      testcase( eDest==SRT_Coroutine );
+      testcase( eDest==SRT_Output );
+      if( pOrderBy ){
+        int r1 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
+        pushOntoSorter(pParse, pOrderBy, p, r1);
+        sqlite3ReleaseTempReg(pParse, r1);
+      }else if( eDest==SRT_Coroutine ){
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
+        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
+      }
+      break;
+    }
+
+#if !defined(SQLITE_OMIT_TRIGGER)
+    /* Discard the results.  This is used for SELECT statements inside
+    ** the body of a TRIGGER.  The purpose of such selects is to call
+    ** user-defined functions that have side effects.  We do not care
+    ** about the actual results of the select.
+    */
+    default: {
+      assert( eDest==SRT_Discard );
+      break;
+    }
+#endif
   }
-  sqlite3_free(db->aExtension);
-  db->aExtension = aHandle;
 
-  db->aExtension[db->nExtension-1] = handle;
-  return SQLITE_OK;
-}
-SQLITE_API int sqlite3_load_extension(
-  sqlite3 *db,          /* Load the extension into this database connection */
-  const char *zFile,    /* Name of the shared library containing extension */
-  const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
-  char **pzErrMsg       /* Put error message here if not 0 */
-){
-  int rc;
-  sqlite3_mutex_enter(db->mutex);
-  rc = sqlite3LoadExtension(db, zFile, zProc, pzErrMsg);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
+  /* Jump to the end of the loop if the LIMIT is reached.
+  */
+  if( p->iLimit ){
+    assert( pOrderBy==0 );  /* If there is an ORDER BY, the call to
+                            ** pushOntoSorter() would have cleared p->iLimit */
+    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
+    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, iBreak);
+  }
 }
 
 /*
-** Call this routine when the database connection is closing in order
-** to clean up loaded extensions
+** Given an expression list, generate a KeyInfo structure that records
+** the collating sequence for each expression in that expression list.
+**
+** If the ExprList is an ORDER BY or GROUP BY clause then the resulting
+** KeyInfo structure is appropriate for initializing a virtual index to
+** implement that clause.  If the ExprList is the result set of a SELECT
+** then the KeyInfo structure is appropriate for initializing a virtual
+** index to implement a DISTINCT test.
+**
+** Space to hold the KeyInfo structure is obtain from malloc.  The calling
+** function is responsible for seeing that this structure is eventually
+** freed.  Add the KeyInfo structure to the P4 field of an opcode using
+** P4_KEYINFO_HANDOFF is the usual way of dealing with this.
 */
-SQLITE_PRIVATE void sqlite3CloseExtensions(sqlite3 *db){
+static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
+  sqlite3 *db = pParse->db;
+  int nExpr;
+  KeyInfo *pInfo;
+  struct ExprList_item *pItem;
   int i;
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(i=0; i<db->nExtension; i++){
-    sqlite3OsDlClose(db->pVfs, db->aExtension[i]);
-  }
-  sqlite3_free(db->aExtension);
-}
 
-/*
-** Enable or disable extension loading.  Extension loading is disabled by
-** default so as not to open security holes in older applications.
-*/
-SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
-  sqlite3_mutex_enter(db->mutex);
-  if( onoff ){
-    db->flags |= SQLITE_LoadExtension;
-  }else{
-    db->flags &= ~SQLITE_LoadExtension;
+  nExpr = pList->nExpr;
+  pInfo = sqlite3DbMallocZero(db, sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) );
+  if( pInfo ){
+    pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr];
+    pInfo->nField = (u16)nExpr;
+    pInfo->enc = ENC(db);
+    pInfo->db = db;
+    for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
+      CollSeq *pColl;
+      pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
+      if( !pColl ){
+        pColl = db->pDfltColl;
+      }
+      pInfo->aColl[i] = pColl;
+      pInfo->aSortOrder[i] = pItem->sortOrder;
+    }
   }
-  sqlite3_mutex_leave(db->mutex);
-  return SQLITE_OK;
+  return pInfo;
 }
 
-#endif /* SQLITE_OMIT_LOAD_EXTENSION */
 
 /*
-** The auto-extension code added regardless of whether or not extension
-** loading is supported.  We need a dummy sqlite3Apis pointer for that
-** code if regular extension loading is not available.  This is that
-** dummy pointer.
+** If the inner loop was generated using a non-null pOrderBy argument,
+** then the results were placed in a sorter.  After the loop is terminated
+** we need to run the sorter and output the results.  The following
+** routine generates the code needed to do that.
 */
-#ifdef SQLITE_OMIT_LOAD_EXTENSION
-static const sqlite3_api_routines sqlite3Apis = { 0 };
+static void generateSortTail(
+  Parse *pParse,    /* Parsing context */
+  Select *p,        /* The SELECT statement */
+  Vdbe *v,          /* Generate code into this VDBE */
+  int nColumn,      /* Number of columns of data */
+  SelectDest *pDest /* Write the sorted results here */
+){
+  int addrBreak = sqlite3VdbeMakeLabel(v);     /* Jump here to exit loop */
+  int addrContinue = sqlite3VdbeMakeLabel(v);  /* Jump here for next cycle */
+  int addr;
+  int iTab;
+  int pseudoTab = 0;
+  ExprList *pOrderBy = p->pOrderBy;
+
+  int eDest = pDest->eDest;
+  int iParm = pDest->iParm;
+
+  int regRow;
+  int regRowid;
+
+  iTab = pOrderBy->iECursor;
+  regRow = sqlite3GetTempReg(pParse);
+  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
+    pseudoTab = pParse->nTab++;
+    sqlite3VdbeAddOp3(v, OP_OpenPseudo, pseudoTab, regRow, nColumn);
+    regRowid = 0;
+  }else{
+    regRowid = sqlite3GetTempReg(pParse);
+  }
+  addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak);
+  codeOffset(v, p, addrContinue);
+  sqlite3VdbeAddOp3(v, OP_Column, iTab, pOrderBy->nExpr + 1, regRow);
+  switch( eDest ){
+    case SRT_Table:
+    case SRT_EphemTab: {
+      testcase( eDest==SRT_Table );
+      testcase( eDest==SRT_EphemTab );
+      sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, regRowid);
+      sqlite3VdbeAddOp3(v, OP_Insert, iParm, regRow, regRowid);
+      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+      break;
+    }
+#ifndef SQLITE_OMIT_SUBQUERY
+    case SRT_Set: {
+      assert( nColumn==1 );
+      sqlite3VdbeAddOp4(v, OP_MakeRecord, regRow, 1, regRowid, &p->affinity, 1);
+      sqlite3ExprCacheAffinityChange(pParse, regRow, 1);
+      sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, regRowid);
+      break;
+    }
+    case SRT_Mem: {
+      assert( nColumn==1 );
+      sqlite3ExprCodeMove(pParse, regRow, iParm, 1);
+      /* The LIMIT clause will terminate the loop for us */
+      break;
+    }
 #endif
+    default: {
+      int i;
+      assert( eDest==SRT_Output || eDest==SRT_Coroutine ); 
+      testcase( eDest==SRT_Output );
+      testcase( eDest==SRT_Coroutine );
+      for(i=0; i<nColumn; i++){
+        assert( regRow!=pDest->iMem+i );
+        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
+        if( i==0 ){
+          sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
+        }
+      }
+      if( eDest==SRT_Output ){
+        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
+        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
+      }else{
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+      }
+      break;
+    }
+  }
+  sqlite3ReleaseTempReg(pParse, regRow);
+  sqlite3ReleaseTempReg(pParse, regRowid);
+
+  /* LIMIT has been implemented by the pushOntoSorter() routine.
+  */
+  assert( p->iLimit==0 );
 
+  /* The bottom of the loop
+  */
+  sqlite3VdbeResolveLabel(v, addrContinue);
+  sqlite3VdbeAddOp2(v, OP_Next, iTab, addr);
+  sqlite3VdbeResolveLabel(v, addrBreak);
+  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
+    sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0);
+  }
+}
 
 /*
-** The following object holds the list of automatically loaded
-** extensions.
+** Return a pointer to a string containing the 'declaration type' of the
+** expression pExpr. The string may be treated as static by the caller.
 **
-** This list is shared across threads.  The SQLITE_MUTEX_STATIC_MASTER
-** mutex must be held while accessing this list.
+** The declaration type is the exact datatype definition extracted from the
+** original CREATE TABLE statement if the expression is a column. The
+** declaration type for a ROWID field is INTEGER. Exactly when an expression
+** is considered a column can be complex in the presence of subqueries. The
+** result-set expression in all of the following SELECT statements is 
+** considered a column by this function.
+**
+**   SELECT col FROM tbl;
+**   SELECT (SELECT col FROM tbl;
+**   SELECT (SELECT col FROM tbl);
+**   SELECT abc FROM (SELECT col AS abc FROM tbl);
+** 
+** The declaration type for any expression other than a column is NULL.
 */
-static struct {
-  int nExt;        /* Number of entries in aExt[] */          
-  void **aExt;     /* Pointers to the extension init functions */
-} autoext = { 0, 0 };
+static const char *columnType(
+  NameContext *pNC, 
+  Expr *pExpr,
+  const char **pzOriginDb,
+  const char **pzOriginTab,
+  const char **pzOriginCol
+){
+  char const *zType = 0;
+  char const *zOriginDb = 0;
+  char const *zOriginTab = 0;
+  char const *zOriginCol = 0;
+  int j;
+  if( NEVER(pExpr==0) || pNC->pSrcList==0 ) return 0;
+
+  switch( pExpr->op ){
+    case TK_AGG_COLUMN:
+    case TK_COLUMN: {
+      /* The expression is a column. Locate the table the column is being
+      ** extracted from in NameContext.pSrcList. This table may be real
+      ** database table or a subquery.
+      */
+      Table *pTab = 0;            /* Table structure column is extracted from */
+      Select *pS = 0;             /* Select the column is extracted from */
+      int iCol = pExpr->iColumn;  /* Index of column in pTab */
+      testcase( pExpr->op==TK_AGG_COLUMN );
+      testcase( pExpr->op==TK_COLUMN );
+      while( pNC && !pTab ){
+        SrcList *pTabList = pNC->pSrcList;
+        for(j=0;j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable;j++);
+        if( j<pTabList->nSrc ){
+          pTab = pTabList->a[j].pTab;
+          pS = pTabList->a[j].pSelect;
+        }else{
+          pNC = pNC->pNext;
+        }
+      }
+
+      if( pTab==0 ){
+        /* At one time, code such as "SELECT new.x" within a trigger would
+        ** cause this condition to run.  Since then, we have restructured how
+        ** trigger code is generated and so this condition is no longer 
+        ** possible. However, it can still be true for statements like
+        ** the following:
+        **
+        **   CREATE TABLE t1(col INTEGER);
+        **   SELECT (SELECT t1.col) FROM FROM t1;
+        **
+        ** when columnType() is called on the expression "t1.col" in the 
+        ** sub-select. In this case, set the column type to NULL, even
+        ** though it should really be "INTEGER".
+        **
+        ** This is not a problem, as the column type of "t1.col" is never
+        ** used. When columnType() is called on the expression 
+        ** "(SELECT t1.col)", the correct type is returned (see the TK_SELECT
+        ** branch below.  */
+        break;
+      }
 
+      assert( pTab && pExpr->pTab==pTab );
+      if( pS ){
+        /* The "table" is actually a sub-select or a view in the FROM clause
+        ** of the SELECT statement. Return the declaration type and origin
+        ** data for the result-set column of the sub-select.
+        */
+        if( ALWAYS(iCol>=0 && iCol<pS->pEList->nExpr) ){
+          /* If iCol is less than zero, then the expression requests the
+          ** rowid of the sub-select or view. This expression is legal (see 
+          ** test case misc2.2.2) - it always evaluates to NULL.
+          */
+          NameContext sNC;
+          Expr *p = pS->pEList->a[iCol].pExpr;
+          sNC.pSrcList = pS->pSrc;
+          sNC.pNext = pNC;
+          sNC.pParse = pNC->pParse;
+          zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
+        }
+      }else if( ALWAYS(pTab->pSchema) ){
+        /* A real table */
+        assert( !pS );
+        if( iCol<0 ) iCol = pTab->iPKey;
+        assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
+        if( iCol<0 ){
+          zType = "INTEGER";
+          zOriginCol = "rowid";
+        }else{
+          zType = pTab->aCol[iCol].zType;
+          zOriginCol = pTab->aCol[iCol].zName;
+        }
+        zOriginTab = pTab->zName;
+        if( pNC->pParse ){
+          int iDb = sqlite3SchemaToIndex(pNC->pParse->db, pTab->pSchema);
+          zOriginDb = pNC->pParse->db->aDb[iDb].zName;
+        }
+      }
+      break;
+    }
+#ifndef SQLITE_OMIT_SUBQUERY
+    case TK_SELECT: {
+      /* The expression is a sub-select. Return the declaration type and
+      ** origin info for the single column in the result set of the SELECT
+      ** statement.
+      */
+      NameContext sNC;
+      Select *pS = pExpr->x.pSelect;
+      Expr *p = pS->pEList->a[0].pExpr;
+      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
+      sNC.pSrcList = pS->pSrc;
+      sNC.pNext = pNC;
+      sNC.pParse = pNC->pParse;
+      zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
+      break;
+    }
+#endif
+  }
+  
+  if( pzOriginDb ){
+    assert( pzOriginTab && pzOriginCol );
+    *pzOriginDb = zOriginDb;
+    *pzOriginTab = zOriginTab;
+    *pzOriginCol = zOriginCol;
+  }
+  return zType;
+}
 
 /*
-** Register a statically linked extension that is automatically
-** loaded by every new database connection.
+** Generate code that will tell the VDBE the declaration types of columns
+** in the result set.
 */
-SQLITE_API int sqlite3_auto_extension(void *xInit){
+static void generateColumnTypes(
+  Parse *pParse,      /* Parser context */
+  SrcList *pTabList,  /* List of tables */
+  ExprList *pEList    /* Expressions defining the result set */
+){
+#ifndef SQLITE_OMIT_DECLTYPE
+  Vdbe *v = pParse->pVdbe;
   int i;
-  int rc = SQLITE_OK;
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
+  NameContext sNC;
+  sNC.pSrcList = pTabList;
+  sNC.pParse = pParse;
+  for(i=0; i<pEList->nExpr; i++){
+    Expr *p = pEList->a[i].pExpr;
+    const char *zType;
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+    const char *zOrigDb = 0;
+    const char *zOrigTab = 0;
+    const char *zOrigCol = 0;
+    zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol);
+
+    /* The vdbe must make its own copy of the column-type and other 
+    ** column specific strings, in case the schema is reset before this
+    ** virtual machine is deleted.
+    */
+    sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, SQLITE_TRANSIENT);
+    sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, SQLITE_TRANSIENT);
+    sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, SQLITE_TRANSIENT);
+#else
+    zType = columnType(&sNC, p, 0, 0, 0);
 #endif
-  sqlite3_mutex_enter(mutex);
-  for(i=0; i<autoext.nExt; i++){
-    if( autoext.aExt[i]==xInit ) break;
-  }
-  if( i==autoext.nExt ){
-    int nByte = (autoext.nExt+1)*sizeof(autoext.aExt[0]);
-    void **aNew;
-    aNew = sqlite3_realloc(autoext.aExt, nByte);
-    if( aNew==0 ){
-      rc = SQLITE_NOMEM;
-    }else{
-      autoext.aExt = aNew;
-      autoext.aExt[autoext.nExt] = xInit;
-      autoext.nExt++;
-    }
+    sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, SQLITE_TRANSIENT);
   }
-  sqlite3_mutex_leave(mutex);
-  assert( (rc&0xff)==rc );
-  return rc;
+#endif /* SQLITE_OMIT_DECLTYPE */
 }
 
 /*
-** Reset the automatic extension loading mechanism.
+** Generate code that will tell the VDBE the names of columns
+** in the result set.  This information is used to provide the
+** azCol[] values in the callback.
 */
-SQLITE_API void sqlite3_reset_auto_extension(void){
-#ifndef SQLITE_MUTEX_NOOP
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
+static void generateColumnNames(
+  Parse *pParse,      /* Parser context */
+  SrcList *pTabList,  /* List of tables */
+  ExprList *pEList    /* Expressions defining the result set */
+){
+  Vdbe *v = pParse->pVdbe;
+  int i, j;
+  sqlite3 *db = pParse->db;
+  int fullNames, shortNames;
+
+#ifndef SQLITE_OMIT_EXPLAIN
+  /* If this is an EXPLAIN, skip this step */
+  if( pParse->explain ){
+    return;
+  }
 #endif
-  sqlite3_mutex_enter(mutex);
-  sqlite3_free(autoext.aExt);
-  autoext.aExt = 0;
-  autoext.nExt = 0;
-  sqlite3_mutex_leave(mutex);
+
+  if( pParse->colNamesSet || NEVER(v==0) || db->mallocFailed ) return;
+  pParse->colNamesSet = 1;
+  fullNames = (db->flags & SQLITE_FullColNames)!=0;
+  shortNames = (db->flags & SQLITE_ShortColNames)!=0;
+  sqlite3VdbeSetNumCols(v, pEList->nExpr);
+  for(i=0; i<pEList->nExpr; i++){
+    Expr *p;
+    p = pEList->a[i].pExpr;
+    if( NEVER(p==0) ) continue;
+    if( pEList->a[i].zName ){
+      char *zName = pEList->a[i].zName;
+      sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_TRANSIENT);
+    }else if( (p->op==TK_COLUMN || p->op==TK_AGG_COLUMN) && pTabList ){
+      Table *pTab;
+      char *zCol;
+      int iCol = p->iColumn;
+      for(j=0; ALWAYS(j<pTabList->nSrc); j++){
+        if( pTabList->a[j].iCursor==p->iTable ) break;
+      }
+      assert( j<pTabList->nSrc );
+      pTab = pTabList->a[j].pTab;
+      if( iCol<0 ) iCol = pTab->iPKey;
+      assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
+      if( iCol<0 ){
+        zCol = "rowid";
+      }else{
+        zCol = pTab->aCol[iCol].zName;
+      }
+      if( !shortNames && !fullNames ){
+        sqlite3VdbeSetColName(v, i, COLNAME_NAME, 
+            sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC);
+      }else if( fullNames ){
+        char *zName = 0;
+        zName = sqlite3MPrintf(db, "%s.%s", pTab->zName, zCol);
+        sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_DYNAMIC);
+      }else{
+        sqlite3VdbeSetColName(v, i, COLNAME_NAME, zCol, SQLITE_TRANSIENT);
+      }
+    }else{
+      sqlite3VdbeSetColName(v, i, COLNAME_NAME, 
+          sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC);
+    }
+  }
+  generateColumnTypes(pParse, pTabList, pEList);
 }
 
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
-** Load all automatic extensions.
+** Name of the connection operator, used for error messages.
 */
-SQLITE_PRIVATE int sqlite3AutoLoadExtensions(sqlite3 *db){
-  int i;
-  int go = 1;
-  int rc = SQLITE_OK;
-  int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
-
-  if( autoext.nExt==0 ){
-    /* Common case: early out without every having to acquire a mutex */
-    return SQLITE_OK;
-  }
-  for(i=0; go; i++){
-    char *zErrmsg = 0;
-#ifndef SQLITE_MUTEX_NOOP
-    sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-#endif
-    sqlite3_mutex_enter(mutex);
-    if( i>=autoext.nExt ){
-      xInit = 0;
-      go = 0;
-    }else{
-      xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
-              autoext.aExt[i];
-    }
-    sqlite3_mutex_leave(mutex);
-    if( xInit && xInit(db, &zErrmsg, &sqlite3Apis) ){
-      sqlite3Error(db, SQLITE_ERROR,
-            "automatic extension loading failed: %s", zErrmsg);
-      go = 0;
-      rc = SQLITE_ERROR;
-      sqlite3_free(zErrmsg);
-    }
+static const char *selectOpName(int id){
+  char *z;
+  switch( id ){
+    case TK_ALL:       z = "UNION ALL";   break;
+    case TK_INTERSECT: z = "INTERSECT";   break;
+    case TK_EXCEPT:    z = "EXCEPT";      break;
+    default:           z = "UNION";       break;
   }
-  return rc;
+  return z;
 }
+#endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
-/************** End of loadext.c *********************************************/
-/************** Begin file pragma.c ******************************************/
 /*
-** 2003 April 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Given a an expression list (which is really the list of expressions
+** that form the result set of a SELECT statement) compute appropriate
+** column names for a table that would hold the expression list.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** All column names will be unique.
 **
-*************************************************************************
-** This file contains code used to implement the PRAGMA command.
+** Only the column names are computed.  Column.zType, Column.zColl,
+** and other fields of Column are zeroed.
 **
-** $Id: pragma.c,v 1.176 2008/04/17 20:59:38 drh Exp $
-*/
-
-/* Ignore this whole file if pragmas are disabled
+** Return SQLITE_OK on success.  If a memory allocation error occurs,
+** store NULL in *paCol and 0 in *pnCol and return SQLITE_NOMEM.
 */
-#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)
+static int selectColumnsFromExprList(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pEList,       /* Expr list from which to derive column names */
+  int *pnCol,             /* Write the number of columns here */
+  Column **paCol          /* Write the new column list here */
+){
+  sqlite3 *db = pParse->db;   /* Database connection */
+  int i, j;                   /* Loop counters */
+  int cnt;                    /* Index added to make the name unique */
+  Column *aCol, *pCol;        /* For looping over result columns */
+  int nCol;                   /* Number of columns in the result set */
+  Expr *p;                    /* Expression for a single result column */
+  char *zName;                /* Column name */
+  int nName;                  /* Size of name in zName[] */
+
+  *pnCol = nCol = pEList->nExpr;
+  aCol = *paCol = sqlite3DbMallocZero(db, sizeof(aCol[0])*nCol);
+  if( aCol==0 ) return SQLITE_NOMEM;
+  for(i=0, pCol=aCol; i<nCol; i++, pCol++){
+    /* Get an appropriate name for the column
+    */
+    p = pEList->a[i].pExpr;
+    assert( p->pRight==0 || ExprHasProperty(p->pRight, EP_IntValue)
+               || p->pRight->u.zToken==0 || p->pRight->u.zToken[0]!=0 );
+    if( (zName = pEList->a[i].zName)!=0 ){
+      /* If the column contains an "AS <name>" phrase, use <name> as the name */
+      zName = sqlite3DbStrDup(db, zName);
+    }else{
+      Expr *pColExpr = p;  /* The expression that is the result column name */
+      Table *pTab;         /* Table associated with this expression */
+      while( pColExpr->op==TK_DOT ) pColExpr = pColExpr->pRight;
+      if( pColExpr->op==TK_COLUMN && ALWAYS(pColExpr->pTab!=0) ){
+        /* For columns use the column name name */
+        int iCol = pColExpr->iColumn;
+        pTab = pColExpr->pTab;
+        if( iCol<0 ) iCol = pTab->iPKey;
+        zName = sqlite3MPrintf(db, "%s",
+                 iCol>=0 ? pTab->aCol[iCol].zName : "rowid");
+      }else if( pColExpr->op==TK_ID ){
+        assert( !ExprHasProperty(pColExpr, EP_IntValue) );
+        zName = sqlite3MPrintf(db, "%s", pColExpr->u.zToken);
+      }else{
+        /* Use the original text of the column expression as its name */
+        zName = sqlite3MPrintf(db, "%s", pEList->a[i].zSpan);
+      }
+    }
+    if( db->mallocFailed ){
+      sqlite3DbFree(db, zName);
+      break;
+    }
 
-/*
-** Interpret the given string as a safety level.  Return 0 for OFF,
-** 1 for ON or NORMAL and 2 for FULL.  Return 1 for an empty or 
-** unrecognized string argument.
-**
-** Note that the values returned are one less that the values that
-** should be passed into sqlite3BtreeSetSafetyLevel().  The is done
-** to support legacy SQL code.  The safety level used to be boolean
-** and older scripts may have used numbers 0 for OFF and 1 for ON.
-*/
-static int getSafetyLevel(const char *z){
-                             /* 123456789 123456789 */
-  static const char zText[] = "onoffalseyestruefull";
-  static const u8 iOffset[] = {0, 1, 2, 4, 9, 12, 16};
-  static const u8 iLength[] = {2, 2, 3, 5, 3, 4, 4};
-  static const u8 iValue[] =  {1, 0, 0, 0, 1, 1, 2};
-  int i, n;
-  if( isdigit(*z) ){
-    return atoi(z);
+    /* Make sure the column name is unique.  If the name is not unique,
+    ** append a integer to the name so that it becomes unique.
+    */
+    nName = sqlite3Strlen30(zName);
+    for(j=cnt=0; j<i; j++){
+      if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){
+        char *zNewName;
+        zName[nName] = 0;
+        zNewName = sqlite3MPrintf(db, "%s:%d", zName, ++cnt);
+        sqlite3DbFree(db, zName);
+        zName = zNewName;
+        j = -1;
+        if( zName==0 ) break;
+      }
+    }
+    pCol->zName = zName;
   }
-  n = strlen(z);
-  for(i=0; i<sizeof(iLength); i++){
-    if( iLength[i]==n && sqlite3StrNICmp(&zText[iOffset[i]],z,n)==0 ){
-      return iValue[i];
+  if( db->mallocFailed ){
+    for(j=0; j<i; j++){
+      sqlite3DbFree(db, aCol[j].zName);
     }
+    sqlite3DbFree(db, aCol);
+    *paCol = 0;
+    *pnCol = 0;
+    return SQLITE_NOMEM;
   }
-  return 1;
+  return SQLITE_OK;
 }
 
 /*
-** Interpret the given string as a boolean value.
-*/
-static int getBoolean(const char *z){
-  return getSafetyLevel(z)&1;
-}
+** Add type and collation information to a column list based on
+** a SELECT statement.
+** 
+** The column list presumably came from selectColumnNamesFromExprList().
+** The column list has only names, not types or collations.  This
+** routine goes through and adds the types and collations.
+**
+** This routine requires that all identifiers in the SELECT
+** statement be resolved.
+*/
+static void selectAddColumnTypeAndCollation(
+  Parse *pParse,        /* Parsing contexts */
+  int nCol,             /* Number of columns */
+  Column *aCol,         /* List of columns */
+  Select *pSelect       /* SELECT used to determine types and collations */
+){
+  sqlite3 *db = pParse->db;
+  NameContext sNC;
+  Column *pCol;
+  CollSeq *pColl;
+  int i;
+  Expr *p;
+  struct ExprList_item *a;
 
-/*
-** Interpret the given string as a locking mode value.
-*/
-static int getLockingMode(const char *z){
-  if( z ){
-    if( 0==sqlite3StrICmp(z, "exclusive") ) return PAGER_LOCKINGMODE_EXCLUSIVE;
-    if( 0==sqlite3StrICmp(z, "normal") ) return PAGER_LOCKINGMODE_NORMAL;
+  assert( pSelect!=0 );
+  assert( (pSelect->selFlags & SF_Resolved)!=0 );
+  assert( nCol==pSelect->pEList->nExpr || db->mallocFailed );
+  if( db->mallocFailed ) return;
+  memset(&sNC, 0, sizeof(sNC));
+  sNC.pSrcList = pSelect->pSrc;
+  a = pSelect->pEList->a;
+  for(i=0, pCol=aCol; i<nCol; i++, pCol++){
+    p = a[i].pExpr;
+    pCol->zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
+    pCol->affinity = sqlite3ExprAffinity(p);
+    if( pCol->affinity==0 ) pCol->affinity = SQLITE_AFF_NONE;
+    pColl = sqlite3ExprCollSeq(pParse, p);
+    if( pColl ){
+      pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
+    }
   }
-  return PAGER_LOCKINGMODE_QUERY;
 }
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
 /*
-** Interpret the given string as an auto-vacuum mode value.
-**
-** The following strings, "none", "full" and "incremental" are 
-** acceptable, as are their numeric equivalents: 0, 1 and 2 respectively.
+** Given a SELECT statement, generate a Table structure that describes
+** the result set of that SELECT.
 */
-static int getAutoVacuum(const char *z){
-  int i;
-  if( 0==sqlite3StrICmp(z, "none") ) return BTREE_AUTOVACUUM_NONE;
-  if( 0==sqlite3StrICmp(z, "full") ) return BTREE_AUTOVACUUM_FULL;
-  if( 0==sqlite3StrICmp(z, "incremental") ) return BTREE_AUTOVACUUM_INCR;
-  i = atoi(z);
-  return ((i>=0&&i<=2)?i:0);
-}
-#endif /* ifndef SQLITE_OMIT_AUTOVACUUM */
+SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect){
+  Table *pTab;
+  sqlite3 *db = pParse->db;
+  int savedFlags;
 
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-/*
-** Interpret the given string as a temp db location. Return 1 for file
-** backed temporary databases, 2 for the Red-Black tree in memory database
-** and 0 to use the compile-time default.
-*/
-static int getTempStore(const char *z){
-  if( z[0]>='0' && z[0]<='2' ){
-    return z[0] - '0';
-  }else if( sqlite3StrICmp(z, "file")==0 ){
-    return 1;
-  }else if( sqlite3StrICmp(z, "memory")==0 ){
-    return 2;
-  }else{
+  savedFlags = db->flags;
+  db->flags &= ~SQLITE_FullColNames;
+  db->flags |= SQLITE_ShortColNames;
+  sqlite3SelectPrep(pParse, pSelect, 0);
+  if( pParse->nErr ) return 0;
+  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
+  db->flags = savedFlags;
+  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
+  if( pTab==0 ){
+    return 0;
+  }
+  /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
+  ** is disabled, so we might as well hard-code pTab->dbMem to NULL. */
+  assert( db->lookaside.bEnabled==0 );
+  pTab->dbMem = 0;
+  pTab->nRef = 1;
+  pTab->zName = 0;
+  selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
+  selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
+  pTab->iPKey = -1;
+  if( db->mallocFailed ){
+    sqlite3DeleteTable(pTab);
     return 0;
   }
+  return pTab;
 }
-#endif /* SQLITE_PAGER_PRAGMAS */
 
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
 /*
-** Invalidate temp storage, either when the temp storage is changed
-** from default, or when 'file' and the temp_store_directory has changed
+** Get a VDBE for the given parser context.  Create a new one if necessary.
+** If an error occurs, return NULL and leave a message in pParse.
 */
-static int invalidateTempStorage(Parse *pParse){
-  sqlite3 *db = pParse->db;
-  if( db->aDb[1].pBt!=0 ){
-    if( !db->autoCommit ){
-      sqlite3ErrorMsg(pParse, "temporary storage cannot be changed "
-        "from within a transaction");
-      return SQLITE_ERROR;
+SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse *pParse){
+  Vdbe *v = pParse->pVdbe;
+  if( v==0 ){
+    v = pParse->pVdbe = sqlite3VdbeCreate(pParse->db);
+#ifndef SQLITE_OMIT_TRACE
+    if( v ){
+      sqlite3VdbeAddOp0(v, OP_Trace);
     }
-    sqlite3BtreeClose(db->aDb[1].pBt);
-    db->aDb[1].pBt = 0;
-    sqlite3ResetInternalSchema(db, 0);
+#endif
   }
-  return SQLITE_OK;
+  return v;
 }
-#endif /* SQLITE_PAGER_PRAGMAS */
 
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+
 /*
-** If the TEMP database is open, close it and mark the database schema
-** as needing reloading.  This must be done when using the TEMP_STORE
-** or DEFAULT_TEMP_STORE pragmas.
+** Compute the iLimit and iOffset fields of the SELECT based on the
+** pLimit and pOffset expressions.  pLimit and pOffset hold the expressions
+** that appear in the original SQL statement after the LIMIT and OFFSET
+** keywords.  Or NULL if those keywords are omitted. iLimit and iOffset 
+** are the integer memory register numbers for counters used to compute 
+** the limit and offset.  If there is no limit and/or offset, then 
+** iLimit and iOffset are negative.
+**
+** This routine changes the values of iLimit and iOffset only if
+** a limit or offset is defined by pLimit and pOffset.  iLimit and
+** iOffset should have been preset to appropriate default values
+** (usually but not always -1) prior to calling this routine.
+** Only if pLimit!=0 or pOffset!=0 do the limit registers get
+** redefined.  The UNION ALL operator uses this property to force
+** the reuse of the same limit and offset registers across multiple
+** SELECT statements.
 */
-static int changeTempStorage(Parse *pParse, const char *zStorageType){
-  int ts = getTempStore(zStorageType);
-  sqlite3 *db = pParse->db;
-  if( db->temp_store==ts ) return SQLITE_OK;
-  if( invalidateTempStorage( pParse ) != SQLITE_OK ){
-    return SQLITE_ERROR;
+static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
+  Vdbe *v = 0;
+  int iLimit = 0;
+  int iOffset;
+  int addr1;
+  if( p->iLimit ) return;
+
+  /* 
+  ** "LIMIT -1" always shows all rows.  There is some
+  ** contraversy about what the correct behavior should be.
+  ** The current implementation interprets "LIMIT 0" to mean
+  ** no rows.
+  */
+  sqlite3ExprCacheClear(pParse);
+  assert( p->pOffset==0 || p->pLimit!=0 );
+  if( p->pLimit ){
+    p->iLimit = iLimit = ++pParse->nMem;
+    v = sqlite3GetVdbe(pParse);
+    if( NEVER(v==0) ) return;  /* VDBE should have already been allocated */
+    sqlite3ExprCode(pParse, p->pLimit, iLimit);
+    sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit);
+    VdbeComment((v, "LIMIT counter"));
+    sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak);
+    if( p->pOffset ){
+      p->iOffset = iOffset = ++pParse->nMem;
+      pParse->nMem++;   /* Allocate an extra register for limit+offset */
+      sqlite3ExprCode(pParse, p->pOffset, iOffset);
+      sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset);
+      VdbeComment((v, "OFFSET counter"));
+      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset);
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset);
+      sqlite3VdbeJumpHere(v, addr1);
+      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
+      VdbeComment((v, "LIMIT+OFFSET"));
+      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit);
+      sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1);
+      sqlite3VdbeJumpHere(v, addr1);
+    }
   }
-  db->temp_store = ts;
-  return SQLITE_OK;
 }
-#endif /* SQLITE_PAGER_PRAGMAS */
 
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
-** Generate code to return a single integer value.
+** Return the appropriate collating sequence for the iCol-th column of
+** the result set for the compound-select statement "p".  Return NULL if
+** the column has no default collating sequence.
+**
+** The collating sequence for the compound select is taken from the
+** left-most term of the select that has a collating sequence.
 */
-static void returnSingleInt(Parse *pParse, const char *zLabel, int value){
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  int mem = ++pParse->nMem;
-  sqlite3VdbeAddOp2(v, OP_Integer, value, mem);
-  if( pParse->explain==0 ){
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, P4_STATIC);
+static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
+  CollSeq *pRet;
+  if( p->pPrior ){
+    pRet = multiSelectCollSeq(pParse, p->pPrior, iCol);
+  }else{
+    pRet = 0;
   }
-  sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
+  assert( iCol>=0 );
+  if( pRet==0 && iCol<p->pEList->nExpr ){
+    pRet = sqlite3ExprCollSeq(pParse, p->pEList->a[iCol].pExpr);
+  }
+  return pRet;
 }
+#endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
-#ifndef SQLITE_OMIT_FLAG_PRAGMAS
-/*
-** Check to see if zRight and zLeft refer to a pragma that queries
-** or changes one of the flags in db->flags.  Return 1 if so and 0 if not.
-** Also, implement the pragma.
-*/
-static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
-  static const struct sPragmaType {
-    const char *zName;  /* Name of the pragma */
-    int mask;           /* Mask for the db->flags value */
-  } aPragma[] = {
-    { "full_column_names",        SQLITE_FullColNames  },
-    { "short_column_names",       SQLITE_ShortColNames },
-    { "count_changes",            SQLITE_CountRows     },
-    { "empty_result_callbacks",   SQLITE_NullCallback  },
-    { "legacy_file_format",       SQLITE_LegacyFileFmt },
-    { "fullfsync",                SQLITE_FullFSync     },
-#ifdef SQLITE_DEBUG
-    { "sql_trace",                SQLITE_SqlTrace      },
-    { "vdbe_listing",             SQLITE_VdbeListing   },
-    { "vdbe_trace",               SQLITE_VdbeTrace     },
-#endif
-#ifndef SQLITE_OMIT_CHECK
-    { "ignore_check_constraints", SQLITE_IgnoreChecks  },
-#endif
-    /* The following is VERY experimental */
-    { "writable_schema",          SQLITE_WriteSchema|SQLITE_RecoveryMode },
-    { "omit_readlock",            SQLITE_NoReadlock    },
-
-    /* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
-    ** flag if there are any active statements. */
-    { "read_uncommitted",         SQLITE_ReadUncommitted },
-  };
-  int i;
-  const struct sPragmaType *p;
-  for(i=0, p=aPragma; i<sizeof(aPragma)/sizeof(aPragma[0]); i++, p++){
-    if( sqlite3StrICmp(zLeft, p->zName)==0 ){
-      sqlite3 *db = pParse->db;
-      Vdbe *v;
-      v = sqlite3GetVdbe(pParse);
-      if( v ){
-        if( zRight==0 ){
-          returnSingleInt(pParse, p->zName, (db->flags & p->mask)!=0 );
-        }else{
-          if( getBoolean(zRight) ){
-            db->flags |= p->mask;
-          }else{
-            db->flags &= ~p->mask;
-          }
-
-          /* Many of the flag-pragmas modify the code generated by the SQL 
-          ** compiler (eg. count_changes). So add an opcode to expire all
-          ** compiled SQL statements after modifying a pragma value.
-          */
-          sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
-        }
-      }
+/* Forward reference */
+static int multiSelectOrderBy(
+  Parse *pParse,        /* Parsing context */
+  Select *p,            /* The right-most of SELECTs to be coded */
+  SelectDest *pDest     /* What to do with query results */
+);
 
-      return 1;
-    }
-  }
-  return 0;
-}
-#endif /* SQLITE_OMIT_FLAG_PRAGMAS */
 
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
-** Process a pragma statement.  
+** This routine is called to process a compound query form from
+** two or more separate queries using UNION, UNION ALL, EXCEPT, or
+** INTERSECT
 **
-** Pragmas are of this form:
+** "p" points to the right-most of the two queries.  the query on the
+** left is p->pPrior.  The left query could also be a compound query
+** in which case this routine will be called recursively. 
 **
-**      PRAGMA [database.]id [= value]
+** The results of the total query are to be written into a destination
+** of type eDest with parameter iParm.
 **
-** The identifier might also be a string.  The value is a string, and
-** identifier, or a number.  If minusFlag is true, then the value is
-** a number that was preceded by a minus sign.
+** Example 1:  Consider a three-way compound SQL statement.
 **
-** If the left side is "database.id" then pId1 is the database name
-** and pId2 is the id.  If the left side is just "id" then pId1 is the
-** id and pId2 is any empty string.
+**     SELECT a FROM t1 UNION SELECT b FROM t2 UNION SELECT c FROM t3
+**
+** This statement is parsed up as follows:
+**
+**     SELECT c FROM t3
+**      |
+**      `----->  SELECT b FROM t2
+**                |
+**                `------>  SELECT a FROM t1
+**
+** The arrows in the diagram above represent the Select.pPrior pointer.
+** So if this routine is called with p equal to the t3 query, then
+** pPrior will be the t2 query.  p->op will be TK_UNION in this case.
+**
+** Notice that because of the way SQLite parses compound SELECTs, the
+** individual selects always group from left to right.
 */
-SQLITE_PRIVATE void sqlite3Pragma(
-  Parse *pParse, 
-  Token *pId1,        /* First part of [database.]id field */
-  Token *pId2,        /* Second part of [database.]id field, or NULL */
-  Token *pValue,      /* Token for <value>, or NULL */
-  int minusFlag       /* True if a '-' sign preceded <value> */
+static int multiSelect(
+  Parse *pParse,        /* Parsing context */
+  Select *p,            /* The right-most of SELECTs to be coded */
+  SelectDest *pDest     /* What to do with query results */
 ){
-  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
-  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
-  const char *zDb = 0;   /* The database name */
-  Token *pId;            /* Pointer to <id> token */
-  int iDb;               /* Database index for <database> */
-  sqlite3 *db = pParse->db;
-  Db *pDb;
-  Vdbe *v = pParse->pVdbe = sqlite3VdbeCreate(db);
-  if( v==0 ) return;
-  pParse->nMem = 2;
-
-  /* Interpret the [database.] part of the pragma statement. iDb is the
-  ** index of the database this pragma is being applied to in db.aDb[]. */
-  iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
-  if( iDb<0 ) return;
-  pDb = &db->aDb[iDb];
+  int rc = SQLITE_OK;   /* Success code from a subroutine */
+  Select *pPrior;       /* Another SELECT immediately to our left */
+  Vdbe *v;              /* Generate code to this VDBE */
+  SelectDest dest;      /* Alternative data destination */
+  Select *pDelete = 0;  /* Chain of simple selects to delete */
+  sqlite3 *db;          /* Database connection */
 
-  /* If the temp database has been explicitly named as part of the 
-  ** pragma, make sure it is open. 
+  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
+  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
   */
-  if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
-    return;
+  assert( p && p->pPrior );  /* Calling function guarantees this much */
+  db = pParse->db;
+  pPrior = p->pPrior;
+  assert( pPrior->pRightmost!=pPrior );
+  assert( pPrior->pRightmost==p->pRightmost );
+  dest = *pDest;
+  if( pPrior->pOrderBy ){
+    sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before",
+      selectOpName(p->op));
+    rc = 1;
+    goto multi_select_end;
+  }
+  if( pPrior->pLimit ){
+    sqlite3ErrorMsg(pParse,"LIMIT clause should come after %s not before",
+      selectOpName(p->op));
+    rc = 1;
+    goto multi_select_end;
   }
 
-  zLeft = sqlite3NameFromToken(db, pId);
-  if( !zLeft ) return;
-  if( minusFlag ){
-    zRight = sqlite3MPrintf(db, "-%T", pValue);
-  }else{
-    zRight = sqlite3NameFromToken(db, pValue);
+  v = sqlite3GetVdbe(pParse);
+  assert( v!=0 );  /* The VDBE already created by calling function */
+
+  /* Create the destination temporary table if necessary
+  */
+  if( dest.eDest==SRT_EphemTab ){
+    assert( p->pEList );
+    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
+    dest.eDest = SRT_Table;
   }
 
-  zDb = ((iDb>0)?pDb->zName:0);
-  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
-    goto pragma_out;
+  /* Make sure all SELECTs in the statement have the same number of elements
+  ** in their result sets.
+  */
+  assert( p->pEList && pPrior->pEList );
+  if( p->pEList->nExpr!=pPrior->pEList->nExpr ){
+    sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s"
+      " do not have the same number of result columns", selectOpName(p->op));
+    rc = 1;
+    goto multi_select_end;
   }
- 
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-  /*
-  **  PRAGMA [database.]default_cache_size
-  **  PRAGMA [database.]default_cache_size=N
-  **
-  ** The first form reports the current persistent setting for the
-  ** page cache size.  The value returned is the maximum number of
-  ** pages in the page cache.  The second form sets both the current
-  ** page cache size value and the persistent page cache size value
-  ** stored in the database file.
-  **
-  ** The default cache size is stored in meta-value 2 of page 1 of the
-  ** database file.  The cache size is actually the absolute value of
-  ** this memory location.  The sign of meta-value 2 determines the
-  ** synchronous setting.  A negative value means synchronous is off
-  ** and a positive value means synchronous is on.
+
+  /* Compound SELECTs that have an ORDER BY clause are handled separately.
   */
-  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
-    static const VdbeOpList getCacheSize[] = {
-      { OP_ReadCookie,  0, 1,        2},  /* 0 */
-      { OP_IfPos,       1, 6,        0},
-      { OP_Integer,     0, 2,        0},
-      { OP_Subtract,    1, 2,        1},
-      { OP_IfPos,       1, 6,        0},
-      { OP_Integer,     0, 1,        0},  /* 5 */
-      { OP_ResultRow,   1, 1,        0},
-    };
-    int addr;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    sqlite3VdbeUsesBtree(v, iDb);
-    if( !zRight ){
-      sqlite3VdbeSetNumCols(v, 1);
-      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", P4_STATIC);
-      pParse->nMem += 2;
-      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
-      sqlite3VdbeChangeP1(v, addr, iDb);
-      sqlite3VdbeChangeP1(v, addr+5, SQLITE_DEFAULT_CACHE_SIZE);
-    }else{
-      int size = atoi(zRight);
-      if( size<0 ) size = -size;
-      sqlite3BeginWriteOperation(pParse, 0, iDb);
-      sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
-      sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, 2, 2);
-      addr = sqlite3VdbeAddOp2(v, OP_IfPos, 2, 0);
-      sqlite3VdbeAddOp2(v, OP_Integer, -size, 1);
-      sqlite3VdbeJumpHere(v, addr);
-      sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 2, 1);
-      pDb->pSchema->cache_size = size;
-      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
-    }
-  }else
+  if( p->pOrderBy ){
+    return multiSelectOrderBy(pParse, p, pDest);
+  }
 
-  /*
-  **  PRAGMA [database.]page_size
-  **  PRAGMA [database.]page_size=N
-  **
-  ** The first form reports the current setting for the
-  ** database page size in bytes.  The second form sets the
-  ** database page size value.  The value can only be set if
-  ** the database has not yet been created.
+  /* Generate code for the left and right SELECT statements.
   */
-  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
-    Btree *pBt = pDb->pBt;
-    if( !zRight ){
-      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
-      returnSingleInt(pParse, "page_size", size);
-    }else{
-      /* Malloc may fail when setting the page-size, as there is an internal
-      ** buffer that the pager module resizes using sqlite3_realloc().
-      */
-      db->nextPagesize = atoi(zRight);
-      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1) ){
-        db->mallocFailed = 1;
+  switch( p->op ){
+    case TK_ALL: {
+      int addr = 0;
+      assert( !pPrior->pLimit );
+      pPrior->pLimit = p->pLimit;
+      pPrior->pOffset = p->pOffset;
+      rc = sqlite3Select(pParse, pPrior, &dest);
+      p->pLimit = 0;
+      p->pOffset = 0;
+      if( rc ){
+        goto multi_select_end;
+      }
+      p->pPrior = 0;
+      p->iLimit = pPrior->iLimit;
+      p->iOffset = pPrior->iOffset;
+      if( p->iLimit ){
+        addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit);
+        VdbeComment((v, "Jump ahead if LIMIT reached"));
+      }
+      rc = sqlite3Select(pParse, p, &dest);
+      testcase( rc!=SQLITE_OK );
+      pDelete = p->pPrior;
+      p->pPrior = pPrior;
+      if( addr ){
+        sqlite3VdbeJumpHere(v, addr);
       }
+      break;
     }
-  }else
+    case TK_EXCEPT:
+    case TK_UNION: {
+      int unionTab;    /* Cursor number of the temporary table holding result */
+      u8 op = 0;       /* One of the SRT_ operations to apply to self */
+      int priorOp;     /* The SRT_ operation to apply to prior selects */
+      Expr *pLimit, *pOffset; /* Saved values of p->nLimit and p->nOffset */
+      int addr;
+      SelectDest uniondest;
 
-  /*
-  **  PRAGMA [database.]max_page_count
-  **  PRAGMA [database.]max_page_count=N
-  **
-  ** The first form reports the current setting for the
-  ** maximum number of pages in the database file.  The 
-  ** second form attempts to change this setting.  Both
-  ** forms return the current setting.
-  */
-  if( sqlite3StrICmp(zLeft,"max_page_count")==0 ){
-    Btree *pBt = pDb->pBt;
-    int newMax = 0;
-    if( zRight ){
-      newMax = atoi(zRight);
-    }
-    if( pBt ){
-      newMax = sqlite3BtreeMaxPageCount(pBt, newMax);
-    }
-    returnSingleInt(pParse, "max_page_count", newMax);
-  }else
+      testcase( p->op==TK_EXCEPT );
+      testcase( p->op==TK_UNION );
+      priorOp = SRT_Union;
+      if( dest.eDest==priorOp && ALWAYS(!p->pLimit &&!p->pOffset) ){
+        /* We can reuse a temporary table generated by a SELECT to our
+        ** right.
+        */
+        assert( p->pRightmost!=p );  /* Can only happen for leftward elements
+                                     ** of a 3-way or more compound */
+        assert( p->pLimit==0 );      /* Not allowed on leftward elements */
+        assert( p->pOffset==0 );     /* Not allowed on leftward elements */
+        unionTab = dest.iParm;
+      }else{
+        /* We will need to create our own temporary table to hold the
+        ** intermediate results.
+        */
+        unionTab = pParse->nTab++;
+        assert( p->pOrderBy==0 );
+        addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);
+        assert( p->addrOpenEphm[0] == -1 );
+        p->addrOpenEphm[0] = addr;
+        p->pRightmost->selFlags |= SF_UsesEphemeral;
+        assert( p->pEList );
+      }
 
-  /*
-  **  PRAGMA [database.]locking_mode
-  **  PRAGMA [database.]locking_mode = (normal|exclusive)
-  */
-  if( sqlite3StrICmp(zLeft,"locking_mode")==0 ){
-    const char *zRet = "normal";
-    int eMode = getLockingMode(zRight);
+      /* Code the SELECT statements to our left
+      */
+      assert( !pPrior->pOrderBy );
+      sqlite3SelectDestInit(&uniondest, priorOp, unionTab);
+      rc = sqlite3Select(pParse, pPrior, &uniondest);
+      if( rc ){
+        goto multi_select_end;
+      }
 
-    if( pId2->n==0 && eMode==PAGER_LOCKINGMODE_QUERY ){
-      /* Simple "PRAGMA locking_mode;" statement. This is a query for
-      ** the current default locking mode (which may be different to
-      ** the locking-mode of the main database).
+      /* Code the current SELECT statement
       */
-      eMode = db->dfltLockMode;
-    }else{
-      Pager *pPager;
-      if( pId2->n==0 ){
-        /* This indicates that no database name was specified as part
-        ** of the PRAGMA command. In this case the locking-mode must be
-        ** set on all attached databases, as well as the main db file.
-        **
-        ** Also, the sqlite3.dfltLockMode variable is set so that
-        ** any subsequently attached databases also use the specified
-        ** locking mode.
-        */
-        int ii;
-        assert(pDb==&db->aDb[0]);
-        for(ii=2; ii<db->nDb; ii++){
-          pPager = sqlite3BtreePager(db->aDb[ii].pBt);
-          sqlite3PagerLockingMode(pPager, eMode);
+      if( p->op==TK_EXCEPT ){
+        op = SRT_Except;
+      }else{
+        assert( p->op==TK_UNION );
+        op = SRT_Union;
+      }
+      p->pPrior = 0;
+      pLimit = p->pLimit;
+      p->pLimit = 0;
+      pOffset = p->pOffset;
+      p->pOffset = 0;
+      uniondest.eDest = op;
+      rc = sqlite3Select(pParse, p, &uniondest);
+      testcase( rc!=SQLITE_OK );
+      /* Query flattening in sqlite3Select() might refill p->pOrderBy.
+      ** Be sure to delete p->pOrderBy, therefore, to avoid a memory leak. */
+      sqlite3ExprListDelete(db, p->pOrderBy);
+      pDelete = p->pPrior;
+      p->pPrior = pPrior;
+      p->pOrderBy = 0;
+      sqlite3ExprDelete(db, p->pLimit);
+      p->pLimit = pLimit;
+      p->pOffset = pOffset;
+      p->iLimit = 0;
+      p->iOffset = 0;
+
+      /* Convert the data in the temporary table into whatever form
+      ** it is that we currently need.
+      */
+      assert( unionTab==dest.iParm || dest.eDest!=priorOp );
+      if( dest.eDest!=priorOp ){
+        int iCont, iBreak, iStart;
+        assert( p->pEList );
+        if( dest.eDest==SRT_Output ){
+          Select *pFirst = p;
+          while( pFirst->pPrior ) pFirst = pFirst->pPrior;
+          generateColumnNames(pParse, 0, pFirst->pEList);
         }
-        db->dfltLockMode = eMode;
+        iBreak = sqlite3VdbeMakeLabel(v);
+        iCont = sqlite3VdbeMakeLabel(v);
+        computeLimitRegisters(pParse, p, iBreak);
+        sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak);
+        iStart = sqlite3VdbeCurrentAddr(v);
+        selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
+                        0, -1, &dest, iCont, iBreak);
+        sqlite3VdbeResolveLabel(v, iCont);
+        sqlite3VdbeAddOp2(v, OP_Next, unionTab, iStart);
+        sqlite3VdbeResolveLabel(v, iBreak);
+        sqlite3VdbeAddOp2(v, OP_Close, unionTab, 0);
       }
-      pPager = sqlite3BtreePager(pDb->pBt);
-      eMode = sqlite3PagerLockingMode(pPager, eMode);
+      break;
     }
+    default: assert( p->op==TK_INTERSECT ); {
+      int tab1, tab2;
+      int iCont, iBreak, iStart;
+      Expr *pLimit, *pOffset;
+      int addr;
+      SelectDest intersectdest;
+      int r1;
 
-    assert(eMode==PAGER_LOCKINGMODE_NORMAL||eMode==PAGER_LOCKINGMODE_EXCLUSIVE);
-    if( eMode==PAGER_LOCKINGMODE_EXCLUSIVE ){
-      zRet = "exclusive";
-    }
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "locking_mode", P4_STATIC);
-    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
-    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
-  }else
+      /* INTERSECT is different from the others since it requires
+      ** two temporary tables.  Hence it has its own case.  Begin
+      ** by allocating the tables we will need.
+      */
+      tab1 = pParse->nTab++;
+      tab2 = pParse->nTab++;
+      assert( p->pOrderBy==0 );
 
-  /*
-  **  PRAGMA [database.]journal_mode
-  **  PRAGMA [database.]journal_mode = (delete|persist|off)
-  */
-  if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
-    int eMode;
-    static const char *azModeName[] = {"delete", "persist", "off"};
+      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab1, 0);
+      assert( p->addrOpenEphm[0] == -1 );
+      p->addrOpenEphm[0] = addr;
+      p->pRightmost->selFlags |= SF_UsesEphemeral;
+      assert( p->pEList );
 
-    if( zRight==0 ){
-      eMode = PAGER_JOURNALMODE_QUERY;
-    }else{
-      int n = strlen(zRight);
-      eMode = 2;
-      while( eMode>=0 && sqlite3StrNICmp(zRight, azModeName[eMode], n)!=0 ){
-        eMode--;
+      /* Code the SELECTs to our left into temporary table "tab1".
+      */
+      sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1);
+      rc = sqlite3Select(pParse, pPrior, &intersectdest);
+      if( rc ){
+        goto multi_select_end;
       }
-    }
-    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
-      /* Simple "PRAGMA persistent_journal;" statement. This is a query for
-      ** the current default journal mode (which may be different to
-      ** the journal-mode of the main database).
+
+      /* Code the current SELECT into temporary table "tab2"
       */
-      eMode = db->dfltJournalMode;
-    }else{
-      Pager *pPager;
-      if( pId2->n==0 ){
-        /* This indicates that no database name was specified as part
-        ** of the PRAGMA command. In this case the journal-mode must be
-        ** set on all attached databases, as well as the main db file.
-        **
-        ** Also, the sqlite3.dfltJournalMode variable is set so that
-        ** any subsequently attached databases also use the specified
-        ** journal mode.
-        */
-        int ii;
-        assert(pDb==&db->aDb[0]);
-        for(ii=1; ii<db->nDb; ii++){
-          if( db->aDb[ii].pBt ){
-            pPager = sqlite3BtreePager(db->aDb[ii].pBt);
-            sqlite3PagerJournalMode(pPager, eMode);
-          }
-        }
-        db->dfltJournalMode = eMode;
+      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab2, 0);
+      assert( p->addrOpenEphm[1] == -1 );
+      p->addrOpenEphm[1] = addr;
+      p->pPrior = 0;
+      pLimit = p->pLimit;
+      p->pLimit = 0;
+      pOffset = p->pOffset;
+      p->pOffset = 0;
+      intersectdest.iParm = tab2;
+      rc = sqlite3Select(pParse, p, &intersectdest);
+      testcase( rc!=SQLITE_OK );
+      pDelete = p->pPrior;
+      p->pPrior = pPrior;
+      sqlite3ExprDelete(db, p->pLimit);
+      p->pLimit = pLimit;
+      p->pOffset = pOffset;
+
+      /* Generate code to take the intersection of the two temporary
+      ** tables.
+      */
+      assert( p->pEList );
+      if( dest.eDest==SRT_Output ){
+        Select *pFirst = p;
+        while( pFirst->pPrior ) pFirst = pFirst->pPrior;
+        generateColumnNames(pParse, 0, pFirst->pEList);
       }
-      pPager = sqlite3BtreePager(pDb->pBt);
-      eMode = sqlite3PagerJournalMode(pPager, eMode);
+      iBreak = sqlite3VdbeMakeLabel(v);
+      iCont = sqlite3VdbeMakeLabel(v);
+      computeLimitRegisters(pParse, p, iBreak);
+      sqlite3VdbeAddOp2(v, OP_Rewind, tab1, iBreak);
+      r1 = sqlite3GetTempReg(pParse);
+      iStart = sqlite3VdbeAddOp2(v, OP_RowKey, tab1, r1);
+      sqlite3VdbeAddOp3(v, OP_NotFound, tab2, iCont, r1);
+      sqlite3ReleaseTempReg(pParse, r1);
+      selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
+                      0, -1, &dest, iCont, iBreak);
+      sqlite3VdbeResolveLabel(v, iCont);
+      sqlite3VdbeAddOp2(v, OP_Next, tab1, iStart);
+      sqlite3VdbeResolveLabel(v, iBreak);
+      sqlite3VdbeAddOp2(v, OP_Close, tab2, 0);
+      sqlite3VdbeAddOp2(v, OP_Close, tab1, 0);
+      break;
     }
-    assert( eMode==PAGER_JOURNALMODE_DELETE
-              || eMode==PAGER_JOURNALMODE_PERSIST
-              || eMode==PAGER_JOURNALMODE_OFF );
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", P4_STATIC);
-    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, 
-           azModeName[eMode], P4_STATIC);
-    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
-  }else
-#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
+  }
 
-  /*
-  **  PRAGMA [database.]auto_vacuum
-  **  PRAGMA [database.]auto_vacuum=N
+  /* Compute collating sequences used by 
+  ** temporary tables needed to implement the compound select.
+  ** Attach the KeyInfo structure to all temporary tables.
   **
-  ** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
+  ** This section is run by the right-most SELECT statement only.
+  ** SELECT statements to the left always skip this part.  The right-most
+  ** SELECT might also skip this part if it has no ORDER BY clause and
+  ** no temp tables are required.
   */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
-    Btree *pBt = pDb->pBt;
-    if( sqlite3ReadSchema(pParse) ){
-      goto pragma_out;
+  if( p->selFlags & SF_UsesEphemeral ){
+    int i;                        /* Loop counter */
+    KeyInfo *pKeyInfo;            /* Collating sequence for the result set */
+    Select *pLoop;                /* For looping through SELECT statements */
+    CollSeq **apColl;             /* For looping through pKeyInfo->aColl[] */
+    int nCol;                     /* Number of columns in result set */
+
+    assert( p->pRightmost==p );
+    nCol = p->pEList->nExpr;
+    pKeyInfo = sqlite3DbMallocZero(db,
+                       sizeof(*pKeyInfo)+nCol*(sizeof(CollSeq*) + 1));
+    if( !pKeyInfo ){
+      rc = SQLITE_NOMEM;
+      goto multi_select_end;
     }
-    if( !zRight ){
-      int auto_vacuum = 
-          pBt ? sqlite3BtreeGetAutoVacuum(pBt) : SQLITE_DEFAULT_AUTOVACUUM;
-      returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
-    }else{
-      int eAuto = getAutoVacuum(zRight);
-      db->nextAutovac = eAuto;
-      if( eAuto>=0 ){
-        /* Call SetAutoVacuum() to set initialize the internal auto and
-        ** incr-vacuum flags. This is required in case this connection
-        ** creates the database file. It is important that it is created
-        ** as an auto-vacuum capable db.
-        */
-        int rc = sqlite3BtreeSetAutoVacuum(pBt, eAuto);
-        if( rc==SQLITE_OK && (eAuto==1 || eAuto==2) ){
-          /* When setting the auto_vacuum mode to either "full" or 
-          ** "incremental", write the value of meta[6] in the database
-          ** file. Before writing to meta[6], check that meta[3] indicates
-          ** that this really is an auto-vacuum capable database.
-          */
-          static const VdbeOpList setMeta6[] = {
-            { OP_Transaction,    0,               1,        0},    /* 0 */
-            { OP_ReadCookie,     0,               1,        3},    /* 1 */
-            { OP_If,             1,               0,        0},    /* 2 */
-            { OP_Halt,           SQLITE_OK,       OE_Abort, 0},    /* 3 */
-            { OP_Integer,        0,               1,        0},    /* 4 */
-            { OP_SetCookie,      0,               6,        1},    /* 5 */
-          };
-          int iAddr;
-          iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);
-          sqlite3VdbeChangeP1(v, iAddr, iDb);
-          sqlite3VdbeChangeP1(v, iAddr+1, iDb);
-          sqlite3VdbeChangeP2(v, iAddr+2, iAddr+4);
-          sqlite3VdbeChangeP1(v, iAddr+4, eAuto-1);
-          sqlite3VdbeChangeP1(v, iAddr+5, iDb);
-          sqlite3VdbeUsesBtree(v, iDb);
-        }
+
+    pKeyInfo->enc = ENC(db);
+    pKeyInfo->nField = (u16)nCol;
+
+    for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){
+      *apColl = multiSelectCollSeq(pParse, p, i);
+      if( 0==*apColl ){
+        *apColl = db->pDfltColl;
       }
     }
-  }else
-#endif
 
-  /*
-  **  PRAGMA [database.]incremental_vacuum(N)
-  **
-  ** Do N steps of incremental vacuuming on a database.
-  */
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  if( sqlite3StrICmp(zLeft,"incremental_vacuum")==0 ){
-    int iLimit, addr;
-    if( sqlite3ReadSchema(pParse) ){
-      goto pragma_out;
-    }
-    if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
-      iLimit = 0x7fffffff;
+    for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
+      for(i=0; i<2; i++){
+        int addr = pLoop->addrOpenEphm[i];
+        if( addr<0 ){
+          /* If [0] is unused then [1] is also unused.  So we can
+          ** always safely abort as soon as the first unused slot is found */
+          assert( pLoop->addrOpenEphm[1]<0 );
+          break;
+        }
+        sqlite3VdbeChangeP2(v, addr, nCol);
+        sqlite3VdbeChangeP4(v, addr, (char*)pKeyInfo, P4_KEYINFO);
+        pLoop->addrOpenEphm[i] = -1;
+      }
     }
-    sqlite3BeginWriteOperation(pParse, 0, iDb);
-    sqlite3VdbeAddOp2(v, OP_Integer, iLimit, 1);
-    addr = sqlite3VdbeAddOp1(v, OP_IncrVacuum, iDb);
-    sqlite3VdbeAddOp1(v, OP_ResultRow, 1);
-    sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
-    sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr);
-    sqlite3VdbeJumpHere(v, addr);
-  }else
-#endif
+    sqlite3DbFree(db, pKeyInfo);
+  }
 
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-  /*
-  **  PRAGMA [database.]cache_size
-  **  PRAGMA [database.]cache_size=N
-  **
-  ** The first form reports the current local setting for the
-  ** page cache size.  The local setting can be different from
-  ** the persistent cache size value that is stored in the database
-  ** file itself.  The value returned is the maximum number of
-  ** pages in the page cache.  The second form sets the local
-  ** page cache size value.  It does not change the persistent
-  ** cache size stored on the disk so the cache size will revert
-  ** to its default value when the database is closed and reopened.
-  ** N should be a positive integer.
-  */
-  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    if( !zRight ){
-      returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
-    }else{
-      int size = atoi(zRight);
-      if( size<0 ) size = -size;
-      pDb->pSchema->cache_size = size;
-      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
-    }
-  }else
+multi_select_end:
+  pDest->iMem = dest.iMem;
+  pDest->nMem = dest.nMem;
+  sqlite3SelectDelete(db, pDelete);
+  return rc;
+}
+#endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
-  /*
-  **   PRAGMA temp_store
-  **   PRAGMA temp_store = "default"|"memory"|"file"
-  **
-  ** Return or set the local value of the temp_store flag.  Changing
-  ** the local value does not make changes to the disk file and the default
-  ** value will be restored the next time the database is opened.
-  **
-  ** Note that it is possible for the library compile-time options to
-  ** override this setting
-  */
-  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
-    if( !zRight ){
-      returnSingleInt(pParse, "temp_store", db->temp_store);
-    }else{
-      changeTempStorage(pParse, zRight);
-    }
-  }else
+/*
+** Code an output subroutine for a coroutine implementation of a
+** SELECT statment.
+**
+** The data to be output is contained in pIn->iMem.  There are
+** pIn->nMem columns to be output.  pDest is where the output should
+** be sent.
+**
+** regReturn is the number of the register holding the subroutine
+** return address.
+**
+** If regPrev>0 then it is a the first register in a vector that
+** records the previous output.  mem[regPrev] is a flag that is false
+** if there has been no previous output.  If regPrev>0 then code is
+** generated to suppress duplicates.  pKeyInfo is used for comparing
+** keys.
+**
+** If the LIMIT found in p->iLimit is reached, jump immediately to
+** iBreak.
+*/
+static int generateOutputSubroutine(
+  Parse *pParse,          /* Parsing context */
+  Select *p,              /* The SELECT statement */
+  SelectDest *pIn,        /* Coroutine supplying data */
+  SelectDest *pDest,      /* Where to send the data */
+  int regReturn,          /* The return address register */
+  int regPrev,            /* Previous result register.  No uniqueness if 0 */
+  KeyInfo *pKeyInfo,      /* For comparing with previous entry */
+  int p4type,             /* The p4 type for pKeyInfo */
+  int iBreak              /* Jump here if we hit the LIMIT */
+){
+  Vdbe *v = pParse->pVdbe;
+  int iContinue;
+  int addr;
 
-  /*
-  **   PRAGMA temp_store_directory
-  **   PRAGMA temp_store_directory = ""|"directory_name"
-  **
-  ** Return or set the local value of the temp_store_directory flag.  Changing
-  ** the value sets a specific directory to be used for temporary files.
-  ** Setting to a null string reverts to the default temporary directory search.
-  ** If temporary directory is changed, then invalidateTempStorage.
-  **
+  addr = sqlite3VdbeCurrentAddr(v);
+  iContinue = sqlite3VdbeMakeLabel(v);
+
+  /* Suppress duplicates for UNION, EXCEPT, and INTERSECT 
   */
-  if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
-    if( !zRight ){
-      if( sqlite3_temp_directory ){
-        sqlite3VdbeSetNumCols(v, 1);
-        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
-            "temp_store_directory", P4_STATIC);
-        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_temp_directory, 0);
-        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
-      }
-    }else{
-      if( zRight[0] 
-       && sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE)==0 
-      ){
-        sqlite3ErrorMsg(pParse, "not a writable directory");
-        goto pragma_out;
-      }
-      if( TEMP_STORE==0
-       || (TEMP_STORE==1 && db->temp_store<=1)
-       || (TEMP_STORE==2 && db->temp_store==1)
-      ){
-        invalidateTempStorage(pParse);
-      }
-      sqlite3_free(sqlite3_temp_directory);
-      if( zRight[0] ){
-        sqlite3_temp_directory = zRight;
-        zRight = 0;
-      }else{
-        sqlite3_temp_directory = 0;
-      }
-    }
-  }else
+  if( regPrev ){
+    int j1, j2;
+    j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
+    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iMem, regPrev+1, pIn->nMem,
+                              (char*)pKeyInfo, p4type);
+    sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
+    sqlite3VdbeJumpHere(v, j1);
+    sqlite3ExprCodeCopy(pParse, pIn->iMem, regPrev+1, pIn->nMem);
+    sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
+  }
+  if( pParse->db->mallocFailed ) return 0;
 
-  /*
-  **   PRAGMA [database.]synchronous
-  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
-  **
-  ** Return or set the local value of the synchronous flag.  Changing
-  ** the local value does not make changes to the disk file and the
-  ** default value will be restored the next time the database is
-  ** opened.
+  /* Suppress the the first OFFSET entries if there is an OFFSET clause
   */
-  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    if( !zRight ){
-      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
-    }else{
-      if( !db->autoCommit ){
-        sqlite3ErrorMsg(pParse, 
-            "Safety level may not be changed inside a transaction");
-      }else{
-        pDb->safety_level = getSafetyLevel(zRight)+1;
-      }
+  codeOffset(v, p, iContinue);
+
+  switch( pDest->eDest ){
+    /* Store the result as data using a unique key.
+    */
+    case SRT_Table:
+    case SRT_EphemTab: {
+      int r1 = sqlite3GetTempReg(pParse);
+      int r2 = sqlite3GetTempReg(pParse);
+      testcase( pDest->eDest==SRT_Table );
+      testcase( pDest->eDest==SRT_EphemTab );
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1);
+      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2);
+      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2);
+      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+      sqlite3ReleaseTempReg(pParse, r2);
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
     }
-  }else
-#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
 
-#ifndef SQLITE_OMIT_FLAG_PRAGMAS
-  if( flagPragma(pParse, zLeft, zRight) ){
-    /* The flagPragma() subroutine also generates any necessary code
-    ** there is nothing more to do here */
-  }else
-#endif /* SQLITE_OMIT_FLAG_PRAGMAS */
+#ifndef SQLITE_OMIT_SUBQUERY
+    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
+    ** then there should be a single item on the stack.  Write this
+    ** item into the set table with bogus data.
+    */
+    case SRT_Set: {
+      int r1;
+      assert( pIn->nMem==1 );
+      p->affinity = 
+         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affinity);
+      r1 = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iMem, 1, r1, &p->affinity, 1);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, 1);
+      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iParm, r1);
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
+    }
 
-#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
-  /*
-  **   PRAGMA table_info(<table>)
-  **
-  ** Return a single row for each column of the named table. The columns of
-  ** the returned data set are:
-  **
-  ** cid:        Column id (numbered from left to right, starting at 0)
-  ** name:       Column name
-  ** type:       Column declaration type.
-  ** notnull:    True if 'NOT NULL' is part of column declaration
-  ** dflt_value: The default value for the column, if any.
-  */
-  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
-    Table *pTab;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    pTab = sqlite3FindTable(db, zRight, zDb);
-    if( pTab ){
-      int i;
-      int nHidden = 0;
-      Column *pCol;
-      sqlite3VdbeSetNumCols(v, 6);
-      pParse->nMem = 6;
-      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", P4_STATIC);
-      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
-      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", P4_STATIC);
-      sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "notnull", P4_STATIC);
-      sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "dflt_value", P4_STATIC);
-      sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "pk", P4_STATIC);
-      sqlite3ViewGetColumnNames(pParse, pTab);
-      for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){
-        const Token *pDflt;
-        if( IsHiddenColumn(pCol) ){
-          nHidden++;
-          continue;
-        }
-        sqlite3VdbeAddOp2(v, OP_Integer, i-nHidden, 1);
-        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pCol->zName, 0);
-        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
-           pCol->zType ? pCol->zType : "", 0);
-        sqlite3VdbeAddOp2(v, OP_Integer, pCol->notNull, 4);
-        if( pCol->pDflt && (pDflt = &pCol->pDflt->span)->z ){
-          sqlite3VdbeAddOp4(v, OP_String8, 0, 5, 0, (char*)pDflt->z, pDflt->n);
-        }else{
-          sqlite3VdbeAddOp2(v, OP_Null, 0, 5);
-        }
-        sqlite3VdbeAddOp2(v, OP_Integer, pCol->isPrimKey, 6);
-        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
-      }
+#if 0  /* Never occurs on an ORDER BY query */
+    /* If any row exist in the result set, record that fact and abort.
+    */
+    case SRT_Exists: {
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iParm);
+      /* The LIMIT clause will terminate the loop for us */
+      break;
     }
-  }else
+#endif
 
-  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
-    Index *pIdx;
-    Table *pTab;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    pIdx = sqlite3FindIndex(db, zRight, zDb);
-    if( pIdx ){
-      int i;
-      pTab = pIdx->pTable;
-      sqlite3VdbeSetNumCols(v, 3);
-      pParse->nMem = 3;
-      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", P4_STATIC);
-      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", P4_STATIC);
-      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", P4_STATIC);
-      for(i=0; i<pIdx->nColumn; i++){
-        int cnum = pIdx->aiColumn[i];
-        sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
-        sqlite3VdbeAddOp2(v, OP_Integer, cnum, 2);
-        assert( pTab->nCol>cnum );
-        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pTab->aCol[cnum].zName, 0);
-        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
-      }
+    /* If this is a scalar select that is part of an expression, then
+    ** store the results in the appropriate memory cell and break out
+    ** of the scan loop.
+    */
+    case SRT_Mem: {
+      assert( pIn->nMem==1 );
+      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iParm, 1);
+      /* The LIMIT clause will jump out of the loop for us */
+      break;
     }
-  }else
+#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
 
-  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
-    Index *pIdx;
-    Table *pTab;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    pTab = sqlite3FindTable(db, zRight, zDb);
-    if( pTab ){
-      v = sqlite3GetVdbe(pParse);
-      pIdx = pTab->pIndex;
-      if( pIdx ){
-        int i = 0; 
-        sqlite3VdbeSetNumCols(v, 3);
-        pParse->nMem = 3;
-        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
-        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
-        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", P4_STATIC);
-        while(pIdx){
-          sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
-          sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
-          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
-          sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
-          ++i;
-          pIdx = pIdx->pNext;
-        }
+    /* The results are stored in a sequence of registers
+    ** starting at pDest->iMem.  Then the co-routine yields.
+    */
+    case SRT_Coroutine: {
+      if( pDest->iMem==0 ){
+        pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
+        pDest->nMem = pIn->nMem;
       }
+      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iMem, pDest->nMem);
+      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+      break;
     }
-  }else
 
-  if( sqlite3StrICmp(zLeft, "database_list")==0 ){
-    int i;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    sqlite3VdbeSetNumCols(v, 3);
-    pParse->nMem = 3;
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
-    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
-    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", P4_STATIC);
-    for(i=0; i<db->nDb; i++){
-      if( db->aDb[i].pBt==0 ) continue;
-      assert( db->aDb[i].zName!=0 );
-      sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, db->aDb[i].zName, 0);
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
-           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
-      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
+    /* If none of the above, then the result destination must be
+    ** SRT_Output.  This routine is never called with any other
+    ** destination other than the ones handled above or SRT_Output.
+    **
+    ** For SRT_Output, results are stored in a sequence of registers.  
+    ** Then the OP_ResultRow opcode is used to cause sqlite3_step() to
+    ** return the next row of result.
+    */
+    default: {
+      assert( pDest->eDest==SRT_Output );
+      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem);
+      break;
     }
-  }else
+  }
 
-  if( sqlite3StrICmp(zLeft, "collation_list")==0 ){
-    int i = 0;
-    HashElem *p;
-    sqlite3VdbeSetNumCols(v, 2);
-    pParse->nMem = 2;
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
-    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
-    for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
-      CollSeq *pColl = (CollSeq *)sqliteHashData(p);
-      sqlite3VdbeAddOp2(v, OP_Integer, i++, 1);
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pColl->zName, 0);
-      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
-    }
-  }else
-#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */
+  /* Jump to the end of the loop if the LIMIT is reached.
+  */
+  if( p->iLimit ){
+    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
+    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, iBreak);
+  }
 
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
-    FKey *pFK;
-    Table *pTab;
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    pTab = sqlite3FindTable(db, zRight, zDb);
-    if( pTab ){
-      v = sqlite3GetVdbe(pParse);
-      pFK = pTab->pFKey;
-      if( pFK ){
-        int i = 0; 
-        sqlite3VdbeSetNumCols(v, 5);
-        pParse->nMem = 5;
-        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", P4_STATIC);
-        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", P4_STATIC);
-        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", P4_STATIC);
-        sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", P4_STATIC);
-        sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", P4_STATIC);
-        while(pFK){
-          int j;
-          for(j=0; j<pFK->nCol; j++){
-            char *zCol = pFK->aCol[j].zCol;
-            sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
-            sqlite3VdbeAddOp2(v, OP_Integer, j, 2);
-            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pFK->zTo, 0);
-            sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
-                              pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
-            sqlite3VdbeAddOp4(v, zCol ? OP_String8 : OP_Null, 0, 5, 0, zCol, 0);
-            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 5);
-          }
-          ++i;
-          pFK = pFK->pNextFrom;
-        }
+  /* Generate the subroutine return
+  */
+  sqlite3VdbeResolveLabel(v, iContinue);
+  sqlite3VdbeAddOp1(v, OP_Return, regReturn);
+
+  return addr;
+}
+
+/*
+** Alternative compound select code generator for cases when there
+** is an ORDER BY clause.
+**
+** We assume a query of the following form:
+**
+**      <selectA>  <operator>  <selectB>  ORDER BY <orderbylist>
+**
+** <operator> is one of UNION ALL, UNION, EXCEPT, or INTERSECT.  The idea
+** is to code both <selectA> and <selectB> with the ORDER BY clause as
+** co-routines.  Then run the co-routines in parallel and merge the results
+** into the output.  In addition to the two coroutines (called selectA and
+** selectB) there are 7 subroutines:
+**
+**    outA:    Move the output of the selectA coroutine into the output
+**             of the compound query.
+**
+**    outB:    Move the output of the selectB coroutine into the output
+**             of the compound query.  (Only generated for UNION and
+**             UNION ALL.  EXCEPT and INSERTSECT never output a row that
+**             appears only in B.)
+**
+**    AltB:    Called when there is data from both coroutines and A<B.
+**
+**    AeqB:    Called when there is data from both coroutines and A==B.
+**
+**    AgtB:    Called when there is data from both coroutines and A>B.
+**
+**    EofA:    Called when data is exhausted from selectA.
+**
+**    EofB:    Called when data is exhausted from selectB.
+**
+** The implementation of the latter five subroutines depend on which 
+** <operator> is used:
+**
+**
+**             UNION ALL         UNION            EXCEPT          INTERSECT
+**          -------------  -----------------  --------------  -----------------
+**   AltB:   outA, nextA      outA, nextA       outA, nextA         nextA
+**
+**   AeqB:   outA, nextA         nextA             nextA         outA, nextA
+**
+**   AgtB:   outB, nextB      outB, nextB          nextB            nextB
+**
+**   EofA:   outB, nextB      outB, nextB          halt             halt
+**
+**   EofB:   outA, nextA      outA, nextA       outA, nextA         halt
+**
+** In the AltB, AeqB, and AgtB subroutines, an EOF on A following nextA
+** causes an immediate jump to EofA and an EOF on B following nextB causes
+** an immediate jump to EofB.  Within EofA and EofB, and EOF on entry or
+** following nextX causes a jump to the end of the select processing.
+**
+** Duplicate removal in the UNION, EXCEPT, and INTERSECT cases is handled
+** within the output subroutine.  The regPrev register set holds the previously
+** output value.  A comparison is made against this value and the output
+** is skipped if the next results would be the same as the previous.
+**
+** The implementation plan is to implement the two coroutines and seven
+** subroutines first, then put the control logic at the bottom.  Like this:
+**
+**          goto Init
+**     coA: coroutine for left query (A)
+**     coB: coroutine for right query (B)
+**    outA: output one row of A
+**    outB: output one row of B (UNION and UNION ALL only)
+**    EofA: ...
+**    EofB: ...
+**    AltB: ...
+**    AeqB: ...
+**    AgtB: ...
+**    Init: initialize coroutine registers
+**          yield coA
+**          if eof(A) goto EofA
+**          yield coB
+**          if eof(B) goto EofB
+**    Cmpr: Compare A, B
+**          Jump AltB, AeqB, AgtB
+**     End: ...
+**
+** We call AltB, AeqB, AgtB, EofA, and EofB "subroutines" but they are not
+** actually called using Gosub and they do not Return.  EofA and EofB loop
+** until all data is exhausted then jump to the "end" labe.  AltB, AeqB,
+** and AgtB jump to either L2 or to one of EofA or EofB.
+*/
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
+static int multiSelectOrderBy(
+  Parse *pParse,        /* Parsing context */
+  Select *p,            /* The right-most of SELECTs to be coded */
+  SelectDest *pDest     /* What to do with query results */
+){
+  int i, j;             /* Loop counters */
+  Select *pPrior;       /* Another SELECT immediately to our left */
+  Vdbe *v;              /* Generate code to this VDBE */
+  SelectDest destA;     /* Destination for coroutine A */
+  SelectDest destB;     /* Destination for coroutine B */
+  int regAddrA;         /* Address register for select-A coroutine */
+  int regEofA;          /* Flag to indicate when select-A is complete */
+  int regAddrB;         /* Address register for select-B coroutine */
+  int regEofB;          /* Flag to indicate when select-B is complete */
+  int addrSelectA;      /* Address of the select-A coroutine */
+  int addrSelectB;      /* Address of the select-B coroutine */
+  int regOutA;          /* Address register for the output-A subroutine */
+  int regOutB;          /* Address register for the output-B subroutine */
+  int addrOutA;         /* Address of the output-A subroutine */
+  int addrOutB = 0;     /* Address of the output-B subroutine */
+  int addrEofA;         /* Address of the select-A-exhausted subroutine */
+  int addrEofB;         /* Address of the select-B-exhausted subroutine */
+  int addrAltB;         /* Address of the A<B subroutine */
+  int addrAeqB;         /* Address of the A==B subroutine */
+  int addrAgtB;         /* Address of the A>B subroutine */
+  int regLimitA;        /* Limit register for select-A */
+  int regLimitB;        /* Limit register for select-A */
+  int regPrev;          /* A range of registers to hold previous output */
+  int savedLimit;       /* Saved value of p->iLimit */
+  int savedOffset;      /* Saved value of p->iOffset */
+  int labelCmpr;        /* Label for the start of the merge algorithm */
+  int labelEnd;         /* Label for the end of the overall SELECT stmt */
+  int j1;               /* Jump instructions that get retargetted */
+  int op;               /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */
+  KeyInfo *pKeyDup = 0; /* Comparison information for duplicate removal */
+  KeyInfo *pKeyMerge;   /* Comparison information for merging rows */
+  sqlite3 *db;          /* Database connection */
+  ExprList *pOrderBy;   /* The ORDER BY clause */
+  int nOrderBy;         /* Number of terms in the ORDER BY clause */
+  int *aPermute;        /* Mapping from ORDER BY terms to result set columns */
+
+  assert( p->pOrderBy!=0 );
+  assert( pKeyDup==0 ); /* "Managed" code needs this.  Ticket #3382. */
+  db = pParse->db;
+  v = pParse->pVdbe;
+  assert( v!=0 );       /* Already thrown the error if VDBE alloc failed */
+  labelEnd = sqlite3VdbeMakeLabel(v);
+  labelCmpr = sqlite3VdbeMakeLabel(v);
+
+
+  /* Patch up the ORDER BY clause
+  */
+  op = p->op;  
+  pPrior = p->pPrior;
+  assert( pPrior->pOrderBy==0 );
+  pOrderBy = p->pOrderBy;
+  assert( pOrderBy );
+  nOrderBy = pOrderBy->nExpr;
+
+  /* For operators other than UNION ALL we have to make sure that
+  ** the ORDER BY clause covers every term of the result set.  Add
+  ** terms to the ORDER BY clause as necessary.
+  */
+  if( op!=TK_ALL ){
+    for(i=1; db->mallocFailed==0 && i<=p->pEList->nExpr; i++){
+      struct ExprList_item *pItem;
+      for(j=0, pItem=pOrderBy->a; j<nOrderBy; j++, pItem++){
+        assert( pItem->iCol>0 );
+        if( pItem->iCol==i ) break;
+      }
+      if( j==nOrderBy ){
+        Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0);
+        if( pNew==0 ) return SQLITE_NOMEM;
+        pNew->flags |= EP_IntValue;
+        pNew->u.iValue = i;
+        pOrderBy = sqlite3ExprListAppend(pParse, pOrderBy, pNew);
+        pOrderBy->a[nOrderBy++].iCol = (u16)i;
       }
     }
-  }else
-#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
+  }
 
-#ifndef NDEBUG
-  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
-    if( zRight ){
-      if( getBoolean(zRight) ){
-        sqlite3ParserTrace(stderr, "parser: ");
-      }else{
-        sqlite3ParserTrace(0, 0);
+  /* Compute the comparison permutation and keyinfo that is used with
+  ** the permutation used to determine if the next
+  ** row of results comes from selectA or selectB.  Also add explicit
+  ** collations to the ORDER BY clause terms so that when the subqueries
+  ** to the right and the left are evaluated, they use the correct
+  ** collation.
+  */
+  aPermute = sqlite3DbMallocRaw(db, sizeof(int)*nOrderBy);
+  if( aPermute ){
+    struct ExprList_item *pItem;
+    for(i=0, pItem=pOrderBy->a; i<nOrderBy; i++, pItem++){
+      assert( pItem->iCol>0  && pItem->iCol<=p->pEList->nExpr );
+      aPermute[i] = pItem->iCol - 1;
+    }
+    pKeyMerge =
+      sqlite3DbMallocRaw(db, sizeof(*pKeyMerge)+nOrderBy*(sizeof(CollSeq*)+1));
+    if( pKeyMerge ){
+      pKeyMerge->aSortOrder = (u8*)&pKeyMerge->aColl[nOrderBy];
+      pKeyMerge->nField = (u16)nOrderBy;
+      pKeyMerge->enc = ENC(db);
+      for(i=0; i<nOrderBy; i++){
+        CollSeq *pColl;
+        Expr *pTerm = pOrderBy->a[i].pExpr;
+        if( pTerm->flags & EP_ExpCollate ){
+          pColl = pTerm->pColl;
+        }else{
+          pColl = multiSelectCollSeq(pParse, p, aPermute[i]);
+          pTerm->flags |= EP_ExpCollate;
+          pTerm->pColl = pColl;
+        }
+        pKeyMerge->aColl[i] = pColl;
+        pKeyMerge->aSortOrder[i] = pOrderBy->a[i].sortOrder;
       }
     }
-  }else
-#endif
+  }else{
+    pKeyMerge = 0;
+  }
 
-  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
-  ** used will be case sensitive or not depending on the RHS.
+  /* Reattach the ORDER BY clause to the query.
   */
-  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
-    if( zRight ){
-      sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
+  p->pOrderBy = pOrderBy;
+  pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy, 0);
+
+  /* Allocate a range of temporary registers and the KeyInfo needed
+  ** for the logic that removes duplicate result rows when the
+  ** operator is UNION, EXCEPT, or INTERSECT (but not UNION ALL).
+  */
+  if( op==TK_ALL ){
+    regPrev = 0;
+  }else{
+    int nExpr = p->pEList->nExpr;
+    assert( nOrderBy>=nExpr || db->mallocFailed );
+    regPrev = sqlite3GetTempRange(pParse, nExpr+1);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev);
+    pKeyDup = sqlite3DbMallocZero(db,
+                  sizeof(*pKeyDup) + nExpr*(sizeof(CollSeq*)+1) );
+    if( pKeyDup ){
+      pKeyDup->aSortOrder = (u8*)&pKeyDup->aColl[nExpr];
+      pKeyDup->nField = (u16)nExpr;
+      pKeyDup->enc = ENC(db);
+      for(i=0; i<nExpr; i++){
+        pKeyDup->aColl[i] = multiSelectCollSeq(pParse, p, i);
+        pKeyDup->aSortOrder[i] = 0;
+      }
     }
-  }else
+  }
+ 
+  /* Separate the left and the right query from one another
+  */
+  p->pPrior = 0;
+  pPrior->pRightmost = 0;
+  sqlite3ResolveOrderGroupBy(pParse, p, p->pOrderBy, "ORDER");
+  if( pPrior->pPrior==0 ){
+    sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER");
+  }
+
+  /* Compute the limit registers */
+  computeLimitRegisters(pParse, p, labelEnd);
+  if( p->iLimit && op==TK_ALL ){
+    regLimitA = ++pParse->nMem;
+    regLimitB = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Copy, p->iOffset ? p->iOffset+1 : p->iLimit,
+                                  regLimitA);
+    sqlite3VdbeAddOp2(v, OP_Copy, regLimitA, regLimitB);
+  }else{
+    regLimitA = regLimitB = 0;
+  }
+  sqlite3ExprDelete(db, p->pLimit);
+  p->pLimit = 0;
+  sqlite3ExprDelete(db, p->pOffset);
+  p->pOffset = 0;
+
+  regAddrA = ++pParse->nMem;
+  regEofA = ++pParse->nMem;
+  regAddrB = ++pParse->nMem;
+  regEofB = ++pParse->nMem;
+  regOutA = ++pParse->nMem;
+  regOutB = ++pParse->nMem;
+  sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA);
+  sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB);
+
+  /* Jump past the various subroutines and coroutines to the main
+  ** merge loop
+  */
+  j1 = sqlite3VdbeAddOp0(v, OP_Goto);
+  addrSelectA = sqlite3VdbeCurrentAddr(v);
+
+
+  /* Generate a coroutine to evaluate the SELECT statement to the
+  ** left of the compound operator - the "A" select.
+  */
+  VdbeNoopComment((v, "Begin coroutine for left SELECT"));
+  pPrior->iLimit = regLimitA;
+  sqlite3Select(pParse, pPrior, &destA);
+  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofA);
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+  VdbeNoopComment((v, "End coroutine for left SELECT"));
+
+  /* Generate a coroutine to evaluate the SELECT statement on 
+  ** the right - the "B" select
+  */
+  addrSelectB = sqlite3VdbeCurrentAddr(v);
+  VdbeNoopComment((v, "Begin coroutine for right SELECT"));
+  savedLimit = p->iLimit;
+  savedOffset = p->iOffset;
+  p->iLimit = regLimitB;
+  p->iOffset = 0;  
+  sqlite3Select(pParse, p, &destB);
+  p->iLimit = savedLimit;
+  p->iOffset = savedOffset;
+  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofB);
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+  VdbeNoopComment((v, "End coroutine for right SELECT"));
+
+  /* Generate a subroutine that outputs the current row of the A
+  ** select as the next output row of the compound select.
+  */
+  VdbeNoopComment((v, "Output routine for A"));
+  addrOutA = generateOutputSubroutine(pParse,
+                 p, &destA, pDest, regOutA,
+                 regPrev, pKeyDup, P4_KEYINFO_HANDOFF, labelEnd);
+  
+  /* Generate a subroutine that outputs the current row of the B
+  ** select as the next output row of the compound select.
+  */
+  if( op==TK_ALL || op==TK_UNION ){
+    VdbeNoopComment((v, "Output routine for B"));
+    addrOutB = generateOutputSubroutine(pParse,
+                 p, &destB, pDest, regOutB,
+                 regPrev, pKeyDup, P4_KEYINFO_STATIC, labelEnd);
+  }
 
-#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
-# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
-#endif
+  /* Generate a subroutine to run when the results from select A
+  ** are exhausted and only data in select B remains.
+  */
+  VdbeNoopComment((v, "eof-A subroutine"));
+  if( op==TK_EXCEPT || op==TK_INTERSECT ){
+    addrEofA = sqlite3VdbeAddOp2(v, OP_Goto, 0, labelEnd);
+  }else{  
+    addrEofA = sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
+    sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofA);
+  }
 
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
-  /* Pragma "quick_check" is an experimental reduced version of 
-  ** integrity_check designed to detect most database corruption
-  ** without most of the overhead of a full integrity-check.
+  /* Generate a subroutine to run when the results from select B
+  ** are exhausted and only data in select A remains.
   */
-  if( sqlite3StrICmp(zLeft, "integrity_check")==0
-   || sqlite3StrICmp(zLeft, "quick_check")==0 
-  ){
-    int i, j, addr, mxErr;
+  if( op==TK_INTERSECT ){
+    addrEofB = addrEofA;
+  }else{  
+    VdbeNoopComment((v, "eof-B subroutine"));
+    addrEofB = sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
+    sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofB);
+  }
 
-    /* Code that appears at the end of the integrity check.  If no error
-    ** messages have been generated, output OK.  Otherwise output the
-    ** error message
-    */
-    static const VdbeOpList endCode[] = {
-      { OP_AddImm,      1, 0,        0},    /* 0 */
-      { OP_IfNeg,       1, 0,        0},    /* 1 */
-      { OP_String8,     0, 3,        0},    /* 2 */
-      { OP_ResultRow,   3, 1,        0},
-    };
+  /* Generate code to handle the case of A<B
+  */
+  VdbeNoopComment((v, "A-lt-B subroutine"));
+  addrAltB = sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
+  sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
 
-    int isQuick = (zLeft[0]=='q');
+  /* Generate code to handle the case of A==B
+  */
+  if( op==TK_ALL ){
+    addrAeqB = addrAltB;
+  }else if( op==TK_INTERSECT ){
+    addrAeqB = addrAltB;
+    addrAltB++;
+  }else{
+    VdbeNoopComment((v, "A-eq-B subroutine"));
+    addrAeqB =
+    sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+    sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
+  }
 
-    /* Initialize the VDBE program */
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-    pParse->nMem = 6;
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", P4_STATIC);
+  /* Generate code to handle the case of A>B
+  */
+  VdbeNoopComment((v, "A-gt-B subroutine"));
+  addrAgtB = sqlite3VdbeCurrentAddr(v);
+  if( op==TK_ALL || op==TK_UNION ){
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
+  }
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
+  sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
 
-    /* Set the maximum error count */
-    mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
-    if( zRight ){
-      mxErr = atoi(zRight);
-      if( mxErr<=0 ){
-        mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
-      }
-    }
-    sqlite3VdbeAddOp2(v, OP_Integer, mxErr, 1);  /* reg[1] holds errors left */
+  /* This code runs once to initialize everything.
+  */
+  sqlite3VdbeJumpHere(v, j1);
+  sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofA);
+  sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofB);
+  sqlite3VdbeAddOp2(v, OP_Gosub, regAddrA, addrSelectA);
+  sqlite3VdbeAddOp2(v, OP_Gosub, regAddrB, addrSelectB);
+  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
+  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
 
-    /* Do an integrity check on each database file */
-    for(i=0; i<db->nDb; i++){
-      HashElem *x;
-      Hash *pTbls;
-      int cnt = 0;
+  /* Implement the main merge loop
+  */
+  sqlite3VdbeResolveLabel(v, labelCmpr);
+  sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
+  sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
+                         (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
+  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
 
-      if( OMIT_TEMPDB && i==1 ) continue;
+  /* Release temporary registers
+  */
+  if( regPrev ){
+    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
+  }
 
-      sqlite3CodeVerifySchema(pParse, i);
-      addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
-      sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
-      sqlite3VdbeJumpHere(v, addr);
+  /* Jump to the this point in order to terminate the query.
+  */
+  sqlite3VdbeResolveLabel(v, labelEnd);
 
-      /* Do an integrity check of the B-Tree
-      **
-      ** Begin by filling registers 2, 3, ... with the root pages numbers
-      ** for all tables and indices in the database.
-      */
-      pTbls = &db->aDb[i].pSchema->tblHash;
-      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
-        Table *pTab = sqliteHashData(x);
-        Index *pIdx;
-        sqlite3VdbeAddOp2(v, OP_Integer, pTab->tnum, 2+cnt);
-        cnt++;
-        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->tnum, 2+cnt);
-          cnt++;
-        }
-      }
-      if( cnt==0 ) continue;
+  /* Set the number of output columns
+  */
+  if( pDest->eDest==SRT_Output ){
+    Select *pFirst = pPrior;
+    while( pFirst->pPrior ) pFirst = pFirst->pPrior;
+    generateColumnNames(pParse, 0, pFirst->pEList);
+  }
 
-      /* Make sure sufficient number of registers have been allocated */
-      if( pParse->nMem < cnt+4 ){
-        pParse->nMem = cnt+4;
-      }
+  /* Reassembly the compound query so that it will be freed correctly
+  ** by the calling function */
+  if( p->pPrior ){
+    sqlite3SelectDelete(db, p->pPrior);
+  }
+  p->pPrior = pPrior;
 
-      /* Do the b-tree integrity checks */
-      sqlite3VdbeAddOp3(v, OP_IntegrityCk, 2, cnt, 1);
-      sqlite3VdbeChangeP5(v, i);
-      addr = sqlite3VdbeAddOp1(v, OP_IsNull, 2);
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
-         sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
-         P4_DYNAMIC);
-      sqlite3VdbeAddOp2(v, OP_Move, 2, 4);
-      sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
-      sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
-      sqlite3VdbeJumpHere(v, addr);
+  /*** TBD:  Insert subroutine calls to close cursors on incomplete
+  **** subqueries ****/
+  return SQLITE_OK;
+}
+#endif
 
-      /* Make sure all the indices are constructed correctly.
-      */
-      for(x=sqliteHashFirst(pTbls); x && !isQuick; x=sqliteHashNext(x)){
-        Table *pTab = sqliteHashData(x);
-        Index *pIdx;
-        int loopTop;
+#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
+/* Forward Declarations */
+static void substExprList(sqlite3*, ExprList*, int, ExprList*);
+static void substSelect(sqlite3*, Select *, int, ExprList *);
 
-        if( pTab->pIndex==0 ) continue;
-        addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);  /* Stop if out of errors */
-        sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
-        sqlite3VdbeJumpHere(v, addr);
-        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, 2);  /* reg(2) will count entries */
-        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
-        sqlite3VdbeAddOp2(v, OP_AddImm, 2, 1);   /* increment entry count */
-        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
-          int jmp2;
-          static const VdbeOpList idxErr[] = {
-            { OP_AddImm,      1, -1,  0},
-            { OP_String8,     0,  3,  0},    /* 1 */
-            { OP_Rowid,       1,  4,  0},
-            { OP_String8,     0,  5,  0},    /* 3 */
-            { OP_String8,     0,  6,  0},    /* 4 */
-            { OP_Concat,      4,  3,  3},
-            { OP_Concat,      5,  3,  3},
-            { OP_Concat,      6,  3,  3},
-            { OP_ResultRow,   3,  1,  0},
-            { OP_IfPos,       1,  0,  0},    /* 9 */
-            { OP_Halt,        0,  0,  0},
-          };
-          sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 1);
-          jmp2 = sqlite3VdbeAddOp3(v, OP_Found, j+2, 0, 3);
-          addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
-          sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
-          sqlite3VdbeChangeP4(v, addr+3, " missing from index ", P4_STATIC);
-          sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
-          sqlite3VdbeJumpHere(v, addr+9);
-          sqlite3VdbeJumpHere(v, jmp2);
-        }
-        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
-        sqlite3VdbeJumpHere(v, loopTop);
-        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
-          static const VdbeOpList cntIdx[] = {
-             { OP_Integer,      0,  3,  0},
-             { OP_Rewind,       0,  0,  0},  /* 1 */
-             { OP_AddImm,       3,  1,  0},
-             { OP_Next,         0,  0,  0},  /* 3 */
-             { OP_Eq,           2,  0,  3},  /* 4 */
-             { OP_AddImm,       1, -1,  0},
-             { OP_String8,      0,  2,  0},  /* 6 */
-             { OP_String8,      0,  3,  0},  /* 7 */
-             { OP_Concat,       3,  2,  2},
-             { OP_ResultRow,    2,  1,  0},
-          };
-          if( pIdx->tnum==0 ) continue;
-          addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);
-          sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
-          sqlite3VdbeJumpHere(v, addr);
-          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
-          sqlite3VdbeChangeP1(v, addr+1, j+2);
-          sqlite3VdbeChangeP2(v, addr+1, addr+4);
-          sqlite3VdbeChangeP1(v, addr+3, j+2);
-          sqlite3VdbeChangeP2(v, addr+3, addr+2);
-          sqlite3VdbeJumpHere(v, addr+4);
-          sqlite3VdbeChangeP4(v, addr+6, 
-                     "wrong # of entries in index ", P4_STATIC);
-          sqlite3VdbeChangeP4(v, addr+7, pIdx->zName, P4_STATIC);
-        }
-      } 
+/*
+** Scan through the expression pExpr.  Replace every reference to
+** a column in table number iTable with a copy of the iColumn-th
+** entry in pEList.  (But leave references to the ROWID column 
+** unchanged.)
+**
+** This routine is part of the flattening procedure.  A subquery
+** whose result set is defined by pEList appears as entry in the
+** FROM clause of a SELECT such that the VDBE cursor assigned to that
+** FORM clause entry is iTable.  This routine make the necessary 
+** changes to pExpr so that it refers directly to the source table
+** of the subquery rather the result set of the subquery.
+*/
+static Expr *substExpr(
+  sqlite3 *db,        /* Report malloc errors to this connection */
+  Expr *pExpr,        /* Expr in which substitution occurs */
+  int iTable,         /* Table to be substituted */
+  ExprList *pEList    /* Substitute expressions */
+){
+  if( pExpr==0 ) return 0;
+  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
+    if( pExpr->iColumn<0 ){
+      pExpr->op = TK_NULL;
+    }else{
+      Expr *pNew;
+      assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
+      assert( pExpr->pLeft==0 && pExpr->pRight==0 );
+      pNew = sqlite3ExprDup(db, pEList->a[pExpr->iColumn].pExpr, 0);
+      if( pNew && pExpr->pColl ){
+        pNew->pColl = pExpr->pColl;
+      }
+      sqlite3ExprDelete(db, pExpr);
+      pExpr = pNew;
     }
-    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
-    sqlite3VdbeChangeP2(v, addr, -mxErr);
-    sqlite3VdbeJumpHere(v, addr+1);
-    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
-  }else
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
+  }else{
+    pExpr->pLeft = substExpr(db, pExpr->pLeft, iTable, pEList);
+    pExpr->pRight = substExpr(db, pExpr->pRight, iTable, pEList);
+    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+      substSelect(db, pExpr->x.pSelect, iTable, pEList);
+    }else{
+      substExprList(db, pExpr->x.pList, iTable, pEList);
+    }
+  }
+  return pExpr;
+}
+static void substExprList(
+  sqlite3 *db,         /* Report malloc errors here */
+  ExprList *pList,     /* List to scan and in which to make substitutes */
+  int iTable,          /* Table to be substituted */
+  ExprList *pEList     /* Substitute values */
+){
+  int i;
+  if( pList==0 ) return;
+  for(i=0; i<pList->nExpr; i++){
+    pList->a[i].pExpr = substExpr(db, pList->a[i].pExpr, iTable, pEList);
+  }
+}
+static void substSelect(
+  sqlite3 *db,         /* Report malloc errors here */
+  Select *p,           /* SELECT statement in which to make substitutions */
+  int iTable,          /* Table to be replaced */
+  ExprList *pEList     /* Substitute values */
+){
+  SrcList *pSrc;
+  struct SrcList_item *pItem;
+  int i;
+  if( !p ) return;
+  substExprList(db, p->pEList, iTable, pEList);
+  substExprList(db, p->pGroupBy, iTable, pEList);
+  substExprList(db, p->pOrderBy, iTable, pEList);
+  p->pHaving = substExpr(db, p->pHaving, iTable, pEList);
+  p->pWhere = substExpr(db, p->pWhere, iTable, pEList);
+  substSelect(db, p->pPrior, iTable, pEList);
+  pSrc = p->pSrc;
+  assert( pSrc );  /* Even for (SELECT 1) we have: pSrc!=0 but pSrc->nSrc==0 */
+  if( ALWAYS(pSrc) ){
+    for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){
+      substSelect(db, pItem->pSelect, iTable, pEList);
+    }
+  }
+}
+#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
+
+#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
+/*
+** This routine attempts to flatten subqueries in order to speed
+** execution.  It returns 1 if it makes changes and 0 if no flattening
+** occurs.
+**
+** To understand the concept of flattening, consider the following
+** query:
+**
+**     SELECT a FROM (SELECT x+y AS a FROM t1 WHERE z<100) WHERE a>5
+**
+** The default way of implementing this query is to execute the
+** subquery first and store the results in a temporary table, then
+** run the outer query on that temporary table.  This requires two
+** passes over the data.  Furthermore, because the temporary table
+** has no indices, the WHERE clause on the outer query cannot be
+** optimized.
+**
+** This routine attempts to rewrite queries such as the above into
+** a single flat select, like this:
+**
+**     SELECT x+y AS a FROM t1 WHERE z<100 AND a>5
+**
+** The code generated for this simpification gives the same result
+** but only has to scan the data once.  And because indices might 
+** exist on the table t1, a complete scan of the data might be
+** avoided.
+**
+** Flattening is only attempted if all of the following are true:
+**
+**   (1)  The subquery and the outer query do not both use aggregates.
+**
+**   (2)  The subquery is not an aggregate or the outer query is not a join.
+**
+**   (3)  The subquery is not the right operand of a left outer join
+**        (Originally ticket #306.  Strenghtened by ticket #3300)
+**
+**   (4)  The subquery is not DISTINCT or the outer query is not a join.
+**
+**   (5)  The subquery is not DISTINCT or the outer query does not use
+**        aggregates.
+**
+**   (6)  The subquery does not use aggregates or the outer query is not
+**        DISTINCT.
+**
+**   (7)  The subquery has a FROM clause.
+**
+**   (8)  The subquery does not use LIMIT or the outer query is not a join.
+**
+**   (9)  The subquery does not use LIMIT or the outer query does not use
+**        aggregates.
+**
+**  (10)  The subquery does not use aggregates or the outer query does not
+**        use LIMIT.
+**
+**  (11)  The subquery and the outer query do not both have ORDER BY clauses.
+**
+**  (12)  Not implemented.  Subsumed into restriction (3).  Was previously
+**        a separate restriction deriving from ticket #350.
+**
+**  (13)  The subquery and outer query do not both use LIMIT
+**
+**  (14)  The subquery does not use OFFSET
+**
+**  (15)  The outer query is not part of a compound select or the
+**        subquery does not have both an ORDER BY and a LIMIT clause.
+**        (See ticket #2339)
+**
+**  (16)  The outer query is not an aggregate or the subquery does
+**        not contain ORDER BY.  (Ticket #2942)  This used to not matter
+**        until we introduced the group_concat() function.  
+**
+**  (17)  The sub-query is not a compound select, or it is a UNION ALL 
+**        compound clause made up entirely of non-aggregate queries, and 
+**        the parent query:
+**
+**          * is not itself part of a compound select,
+**          * is not an aggregate or DISTINCT query, and
+**          * has no other tables or sub-selects in the FROM clause.
+**
+**        The parent and sub-query may contain WHERE clauses. Subject to
+**        rules (11), (13) and (14), they may also contain ORDER BY,
+**        LIMIT and OFFSET clauses.
+**
+**  (18)  If the sub-query is a compound select, then all terms of the
+**        ORDER by clause of the parent must be simple references to 
+**        columns of the sub-query.
+**
+**  (19)  The subquery does not use LIMIT or the outer query does not
+**        have a WHERE clause.
+**
+**  (20)  If the sub-query is a compound select, then it must not use
+**        an ORDER BY clause.  Ticket #3773.  We could relax this constraint
+**        somewhat by saying that the terms of the ORDER BY clause must
+**        appear as unmodified result columns in the outer query.  But
+**        have other optimizations in mind to deal with that case.
+**
+** In this routine, the "p" parameter is a pointer to the outer query.
+** The subquery is p->pSrc->a[iFrom].  isAgg is true if the outer query
+** uses aggregates and subqueryIsAgg is true if the subquery uses aggregates.
+**
+** If flattening is not attempted, this routine is a no-op and returns 0.
+** If flattening is attempted this routine returns 1.
+**
+** All of the expression analysis must occur on both the outer query and
+** the subquery before this routine runs.
+*/
+static int flattenSubquery(
+  Parse *pParse,       /* Parsing context */
+  Select *p,           /* The parent or outer SELECT statement */
+  int iFrom,           /* Index in p->pSrc->a[] of the inner subquery */
+  int isAgg,           /* True if outer SELECT uses aggregate functions */
+  int subqueryIsAgg    /* True if the subquery uses aggregate functions */
+){
+  const char *zSavedAuthContext = pParse->zAuthContext;
+  Select *pParent;
+  Select *pSub;       /* The inner query or "subquery" */
+  Select *pSub1;      /* Pointer to the rightmost select in sub-query */
+  SrcList *pSrc;      /* The FROM clause of the outer query */
+  SrcList *pSubSrc;   /* The FROM clause of the subquery */
+  ExprList *pList;    /* The result set of the outer query */
+  int iParent;        /* VDBE cursor number of the pSub result set temp table */
+  int i;              /* Loop counter */
+  Expr *pWhere;                    /* The WHERE clause */
+  struct SrcList_item *pSubitem;   /* The subquery */
+  sqlite3 *db = pParse->db;
 
-#ifndef SQLITE_OMIT_UTF16
-  /*
-  **   PRAGMA encoding
-  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
+  /* Check to see if flattening is permitted.  Return 0 if not.
+  */
+  assert( p!=0 );
+  assert( p->pPrior==0 );  /* Unable to flatten compound queries */
+  pSrc = p->pSrc;
+  assert( pSrc && iFrom>=0 && iFrom<pSrc->nSrc );
+  pSubitem = &pSrc->a[iFrom];
+  iParent = pSubitem->iCursor;
+  pSub = pSubitem->pSelect;
+  assert( pSub!=0 );
+  if( isAgg && subqueryIsAgg ) return 0;                 /* Restriction (1)  */
+  if( subqueryIsAgg && pSrc->nSrc>1 ) return 0;          /* Restriction (2)  */
+  pSubSrc = pSub->pSrc;
+  assert( pSubSrc );
+  /* Prior to version 3.1.2, when LIMIT and OFFSET had to be simple constants,
+  ** not arbitrary expresssions, we allowed some combining of LIMIT and OFFSET
+  ** because they could be computed at compile-time.  But when LIMIT and OFFSET
+  ** became arbitrary expressions, we were forced to add restrictions (13)
+  ** and (14). */
+  if( pSub->pLimit && p->pLimit ) return 0;              /* Restriction (13) */
+  if( pSub->pOffset ) return 0;                          /* Restriction (14) */
+  if( p->pRightmost && pSub->pLimit && pSub->pOrderBy ){
+    return 0;                                            /* Restriction (15) */
+  }
+  if( pSubSrc->nSrc==0 ) return 0;                       /* Restriction (7)  */
+  if( ((pSub->selFlags & SF_Distinct)!=0 || pSub->pLimit) 
+         && (pSrc->nSrc>1 || isAgg) ){          /* Restrictions (4)(5)(8)(9) */
+     return 0;       
+  }
+  if( (p->selFlags & SF_Distinct)!=0 && subqueryIsAgg ){
+     return 0;         /* Restriction (6)  */
+  }
+  if( p->pOrderBy && pSub->pOrderBy ){
+     return 0;                                           /* Restriction (11) */
+  }
+  if( isAgg && pSub->pOrderBy ) return 0;                /* Restriction (16) */
+  if( pSub->pLimit && p->pWhere ) return 0;              /* Restriction (19) */
+
+  /* OBSOLETE COMMENT 1:
+  ** Restriction 3:  If the subquery is a join, make sure the subquery is 
+  ** not used as the right operand of an outer join.  Examples of why this
+  ** is not allowed:
   **
-  ** In its first form, this pragma returns the encoding of the main
-  ** database. If the database is not initialized, it is initialized now.
+  **         t1 LEFT OUTER JOIN (t2 JOIN t3)
   **
-  ** The second form of this pragma is a no-op if the main database file
-  ** has not already been initialized. In this case it sets the default
-  ** encoding that will be used for the main database file if a new file
-  ** is created. If an existing main database file is opened, then the
-  ** default text encoding for the existing database is used.
-  ** 
-  ** In all cases new databases created using the ATTACH command are
-  ** created to use the same default text encoding as the main database. If
-  ** the main database has not been initialized and/or created when ATTACH
-  ** is executed, this is done before the ATTACH operation.
+  ** If we flatten the above, we would get
   **
-  ** In the second form this pragma sets the text encoding to be used in
-  ** new database files created using this database handle. It is only
-  ** useful if invoked immediately after the main database i
+  **         (t1 LEFT OUTER JOIN t2) JOIN t3
+  **
+  ** which is not at all the same thing.
+  **
+  ** OBSOLETE COMMENT 2:
+  ** Restriction 12:  If the subquery is the right operand of a left outer
+  ** join, make sure the subquery has no WHERE clause.
+  ** An examples of why this is not allowed:
+  **
+  **         t1 LEFT OUTER JOIN (SELECT * FROM t2 WHERE t2.x>0)
+  **
+  ** If we flatten the above, we would get
+  **
+  **         (t1 LEFT OUTER JOIN t2) WHERE t2.x>0
+  **
+  ** But the t2.x>0 test will always fail on a NULL row of t2, which
+  ** effectively converts the OUTER JOIN into an INNER JOIN.
+  **
+  ** THIS OVERRIDES OBSOLETE COMMENTS 1 AND 2 ABOVE:
+  ** Ticket #3300 shows that flattening the right term of a LEFT JOIN
+  ** is fraught with danger.  Best to avoid the whole thing.  If the
+  ** subquery is the right term of a LEFT JOIN, then do not flatten.
   */
-  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
-    static const struct EncName {
-      char *zName;
-      u8 enc;
-    } encnames[] = {
-      { "UTF-8",    SQLITE_UTF8        },
-      { "UTF8",     SQLITE_UTF8        },
-      { "UTF-16le", SQLITE_UTF16LE     },
-      { "UTF16le",  SQLITE_UTF16LE     },
-      { "UTF-16be", SQLITE_UTF16BE     },
-      { "UTF16be",  SQLITE_UTF16BE     },
-      { "UTF-16",   0                  }, /* SQLITE_UTF16NATIVE */
-      { "UTF16",    0                  }, /* SQLITE_UTF16NATIVE */
-      { 0, 0 }
-    };
-    const struct EncName *pEnc;
-    if( !zRight ){    /* "PRAGMA encoding" */
-      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
-      sqlite3VdbeSetNumCols(v, 1);
-      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "encoding", P4_STATIC);
-      sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
-      for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
-        if( pEnc->enc==ENC(pParse->db) ){
-          sqlite3VdbeChangeP4(v, -1, pEnc->zName, P4_STATIC);
-          break;
-        }
-      }
-      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
-    }else{                        /* "PRAGMA encoding = XXX" */
-      /* Only change the value of sqlite.enc if the database handle is not
-      ** initialized. If the main database exists, the new sqlite.enc value
-      ** will be overwritten when the schema is next loaded. If it does not
-      ** already exists, it will be created to use the new encoding value.
-      */
-      if( 
-        !(DbHasProperty(db, 0, DB_SchemaLoaded)) || 
-        DbHasProperty(db, 0, DB_Empty) 
+  if( (pSubitem->jointype & JT_OUTER)!=0 ){
+    return 0;
+  }
+
+  /* Restriction 17: If the sub-query is a compound SELECT, then it must
+  ** use only the UNION ALL operator. And none of the simple select queries
+  ** that make up the compound SELECT are allowed to be aggregate or distinct
+  ** queries.
+  */
+  if( pSub->pPrior ){
+    if( pSub->pOrderBy ){
+      return 0;  /* Restriction 20 */
+    }
+    if( isAgg || (p->selFlags & SF_Distinct)!=0 || pSrc->nSrc!=1 ){
+      return 0;
+    }
+    for(pSub1=pSub; pSub1; pSub1=pSub1->pPrior){
+      testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct );
+      testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate );
+      if( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))!=0
+       || (pSub1->pPrior && pSub1->op!=TK_ALL) 
+       || NEVER(pSub1->pSrc==0) || pSub1->pSrc->nSrc!=1
       ){
-        for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
-          if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
-            ENC(pParse->db) = pEnc->enc ? pEnc->enc : SQLITE_UTF16NATIVE;
-            break;
-          }
-        }
-        if( !pEnc->zName ){
-          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
-        }
+        return 0;
       }
     }
-  }else
-#endif /* SQLITE_OMIT_UTF16 */
 
-#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
-  /*
-  **   PRAGMA [database.]schema_version
-  **   PRAGMA [database.]schema_version = <integer>
+    /* Restriction 18. */
+    if( p->pOrderBy ){
+      int ii;
+      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
+        if( p->pOrderBy->a[ii].iCol==0 ) return 0;
+      }
+    }
+  }
+
+  /***** If we reach this point, flattening is permitted. *****/
+
+  /* Authorize the subquery */
+  pParse->zAuthContext = pSubitem->zName;
+  sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
+  pParse->zAuthContext = zSavedAuthContext;
+
+  /* If the sub-query is a compound SELECT statement, then (by restrictions
+  ** 17 and 18 above) it must be a UNION ALL and the parent query must 
+  ** be of the form:
   **
-  **   PRAGMA [database.]user_version
-  **   PRAGMA [database.]user_version = <integer>
+  **     SELECT <expr-list> FROM (<sub-query>) <where-clause> 
   **
-  ** The pragma's schema_version and user_version are used to set or get
-  ** the value of the schema-version and user-version, respectively. Both
-  ** the schema-version and the user-version are 32-bit signed integers
-  ** stored in the database header.
+  ** followed by any ORDER BY, LIMIT and/or OFFSET clauses. This block
+  ** creates N-1 copies of the parent query without any ORDER BY, LIMIT or 
+  ** OFFSET clauses and joins them to the left-hand-side of the original
+  ** using UNION ALL operators. In this case N is the number of simple
+  ** select statements in the compound sub-query.
   **
-  ** The schema-cookie is usually only manipulated internally by SQLite. It
-  ** is incremented by SQLite whenever the database schema is modified (by
-  ** creating or dropping a table or index). The schema version is used by
-  ** SQLite each time a query is executed to ensure that the internal cache
-  ** of the schema used when compiling the SQL query matches the schema of
-  ** the database against which the compiled query is actually executed.
-  ** Subverting this mechanism by using "PRAGMA schema_version" to modify
-  ** the schema-version is potentially dangerous and may lead to program
-  ** crashes or database corruption. Use with caution!
+  ** Example:
   **
-  ** The user-version is not used internally by SQLite. It may be used by
-  ** applications for any purpose.
+  **     SELECT a+1 FROM (
+  **        SELECT x FROM tab
+  **        UNION ALL
+  **        SELECT y FROM tab
+  **        UNION ALL
+  **        SELECT abs(z*2) FROM tab2
+  **     ) WHERE a!=5 ORDER BY 1
+  **
+  ** Transformed into:
+  **
+  **     SELECT x+1 FROM tab WHERE x+1!=5
+  **     UNION ALL
+  **     SELECT y+1 FROM tab WHERE y+1!=5
+  **     UNION ALL
+  **     SELECT abs(z*2)+1 FROM tab2 WHERE abs(z*2)+1!=5
+  **     ORDER BY 1
+  **
+  ** We call this the "compound-subquery flattening".
   */
-  if( sqlite3StrICmp(zLeft, "schema_version")==0 
-   || sqlite3StrICmp(zLeft, "user_version")==0 
-   || sqlite3StrICmp(zLeft, "freelist_count")==0 
-  ){
+  for(pSub=pSub->pPrior; pSub; pSub=pSub->pPrior){
+    Select *pNew;
+    ExprList *pOrderBy = p->pOrderBy;
+    Expr *pLimit = p->pLimit;
+    Select *pPrior = p->pPrior;
+    p->pOrderBy = 0;
+    p->pSrc = 0;
+    p->pPrior = 0;
+    p->pLimit = 0;
+    pNew = sqlite3SelectDup(db, p, 0);
+    p->pLimit = pLimit;
+    p->pOrderBy = pOrderBy;
+    p->pSrc = pSrc;
+    p->op = TK_ALL;
+    p->pRightmost = 0;
+    if( pNew==0 ){
+      pNew = pPrior;
+    }else{
+      pNew->pPrior = pPrior;
+      pNew->pRightmost = 0;
+    }
+    p->pPrior = pNew;
+    if( db->mallocFailed ) return 1;
+  }
 
-    int iCookie;   /* Cookie index. 0 for schema-cookie, 6 for user-cookie. */
-    sqlite3VdbeUsesBtree(v, iDb);
-    switch( zLeft[0] ){
-      case 's': case 'S':
-        iCookie = 0;
-        break;
-      case 'f': case 'F':
-        iCookie = 1;
-        iDb = (-1*(iDb+1));
-        assert(iDb<=0);
+  /* Begin flattening the iFrom-th entry of the FROM clause 
+  ** in the outer query.
+  */
+  pSub = pSub1 = pSubitem->pSelect;
+
+  /* Delete the transient table structure associated with the
+  ** subquery
+  */
+  sqlite3DbFree(db, pSubitem->zDatabase);
+  sqlite3DbFree(db, pSubitem->zName);
+  sqlite3DbFree(db, pSubitem->zAlias);
+  pSubitem->zDatabase = 0;
+  pSubitem->zName = 0;
+  pSubitem->zAlias = 0;
+  pSubitem->pSelect = 0;
+
+  /* Defer deleting the Table object associated with the
+  ** subquery until code generation is
+  ** complete, since there may still exist Expr.pTab entries that
+  ** refer to the subquery even after flattening.  Ticket #3346.
+  **
+  ** pSubitem->pTab is always non-NULL by test restrictions and tests above.
+  */
+  if( ALWAYS(pSubitem->pTab!=0) ){
+    Table *pTabToDel = pSubitem->pTab;
+    if( pTabToDel->nRef==1 ){
+      Parse *pToplevel = sqlite3ParseToplevel(pParse);
+      pTabToDel->pNextZombie = pToplevel->pZombieTab;
+      pToplevel->pZombieTab = pTabToDel;
+    }else{
+      pTabToDel->nRef--;
+    }
+    pSubitem->pTab = 0;
+  }
+
+  /* The following loop runs once for each term in a compound-subquery
+  ** flattening (as described above).  If we are doing a different kind
+  ** of flattening - a flattening other than a compound-subquery flattening -
+  ** then this loop only runs once.
+  **
+  ** This loop moves all of the FROM elements of the subquery into the
+  ** the FROM clause of the outer query.  Before doing this, remember
+  ** the cursor number for the original outer query FROM element in
+  ** iParent.  The iParent cursor will never be used.  Subsequent code
+  ** will scan expressions looking for iParent references and replace
+  ** those references with expressions that resolve to the subquery FROM
+  ** elements we are now copying in.
+  */
+  for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){
+    int nSubSrc;
+    u8 jointype = 0;
+    pSubSrc = pSub->pSrc;     /* FROM clause of subquery */
+    nSubSrc = pSubSrc->nSrc;  /* Number of terms in subquery FROM clause */
+    pSrc = pParent->pSrc;     /* FROM clause of the outer query */
+
+    if( pSrc ){
+      assert( pParent==p );  /* First time through the loop */
+      jointype = pSubitem->jointype;
+    }else{
+      assert( pParent!=p );  /* 2nd and subsequent times through the loop */
+      pSrc = pParent->pSrc = sqlite3SrcListAppend(db, 0, 0, 0);
+      if( pSrc==0 ){
+        assert( db->mallocFailed );
         break;
-      default:
-        iCookie = 5;
+      }
+    }
+
+    /* The subquery uses a single slot of the FROM clause of the outer
+    ** query.  If the subquery has more than one element in its FROM clause,
+    ** then expand the outer query to make space for it to hold all elements
+    ** of the subquery.
+    **
+    ** Example:
+    **
+    **    SELECT * FROM tabA, (SELECT * FROM sub1, sub2), tabB;
+    **
+    ** The outer query has 3 slots in its FROM clause.  One slot of the
+    ** outer query (the middle slot) is used by the subquery.  The next
+    ** block of code will expand the out query to 4 slots.  The middle
+    ** slot is expanded to two slots in order to make space for the
+    ** two elements in the FROM clause of the subquery.
+    */
+    if( nSubSrc>1 ){
+      pParent->pSrc = pSrc = sqlite3SrcListEnlarge(db, pSrc, nSubSrc-1,iFrom+1);
+      if( db->mallocFailed ){
         break;
+      }
     }
 
-    if( zRight && iDb>=0 ){
-      /* Write the specified cookie value */
-      static const VdbeOpList setCookie[] = {
-        { OP_Transaction,    0,  1,  0},    /* 0 */
-        { OP_Integer,        0,  1,  0},    /* 1 */
-        { OP_SetCookie,      0,  0,  1},    /* 2 */
-      };
-      int addr = sqlite3VdbeAddOpList(v, ArraySize(setCookie), setCookie);
-      sqlite3VdbeChangeP1(v, addr, iDb);
-      sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
-      sqlite3VdbeChangeP1(v, addr+2, iDb);
-      sqlite3VdbeChangeP2(v, addr+2, iCookie);
+    /* Transfer the FROM clause terms from the subquery into the
+    ** outer query.
+    */
+    for(i=0; i<nSubSrc; i++){
+      sqlite3IdListDelete(db, pSrc->a[i+iFrom].pUsing);
+      pSrc->a[i+iFrom] = pSubSrc->a[i];
+      memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i]));
+    }
+    pSrc->a[iFrom].jointype = jointype;
+  
+    /* Now begin substituting subquery result set expressions for 
+    ** references to the iParent in the outer query.
+    ** 
+    ** Example:
+    **
+    **   SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b;
+    **   \                     \_____________ subquery __________/          /
+    **    \_____________________ outer query ______________________________/
+    **
+    ** We look at every expression in the outer query and every place we see
+    ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
+    */
+    pList = pParent->pEList;
+    for(i=0; i<pList->nExpr; i++){
+      if( pList->a[i].zName==0 ){
+        const char *zSpan = pList->a[i].zSpan;
+        if( ALWAYS(zSpan) ){
+          pList->a[i].zName = sqlite3DbStrDup(db, zSpan);
+        }
+      }
+    }
+    substExprList(db, pParent->pEList, iParent, pSub->pEList);
+    if( isAgg ){
+      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
+      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
+    }
+    if( pSub->pOrderBy ){
+      assert( pParent->pOrderBy==0 );
+      pParent->pOrderBy = pSub->pOrderBy;
+      pSub->pOrderBy = 0;
+    }else if( pParent->pOrderBy ){
+      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
+    }
+    if( pSub->pWhere ){
+      pWhere = sqlite3ExprDup(db, pSub->pWhere, 0);
     }else{
-      /* Read the specified cookie value */
-      static const VdbeOpList readCookie[] = {
-        { OP_ReadCookie,      0,  1,  0},    /* 0 */
-        { OP_ResultRow,       1,  1,  0}
-      };
-      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
-      sqlite3VdbeChangeP1(v, addr, iDb);
-      sqlite3VdbeChangeP3(v, addr, iCookie);
-      sqlite3VdbeSetNumCols(v, 1);
-      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, P4_TRANSIENT);
+      pWhere = 0;
+    }
+    if( subqueryIsAgg ){
+      assert( pParent->pHaving==0 );
+      pParent->pHaving = pParent->pWhere;
+      pParent->pWhere = pWhere;
+      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
+      pParent->pHaving = sqlite3ExprAnd(db, pParent->pHaving, 
+                                  sqlite3ExprDup(db, pSub->pHaving, 0));
+      assert( pParent->pGroupBy==0 );
+      pParent->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy, 0);
+    }else{
+      pParent->pWhere = substExpr(db, pParent->pWhere, iParent, pSub->pEList);
+      pParent->pWhere = sqlite3ExprAnd(db, pParent->pWhere, pWhere);
     }
-  }else
-#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */
+  
+    /* The flattened query is distinct if either the inner or the
+    ** outer query is distinct. 
+    */
+    pParent->selFlags |= pSub->selFlags & SF_Distinct;
+  
+    /*
+    ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y;
+    **
+    ** One is tempted to try to add a and b to combine the limits.  But this
+    ** does not work if either limit is negative.
+    */
+    if( pSub->pLimit ){
+      pParent->pLimit = pSub->pLimit;
+      pSub->pLimit = 0;
+    }
+  }
 
-#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
-  /*
-  ** Report the current state of file logs for all databases
+  /* Finially, delete what is left of the subquery and return
+  ** success.
   */
-  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
-    static const char *const azLockName[] = {
-      "unlocked", "shared", "reserved", "pending", "exclusive"
-    };
-    int i;
-    Vdbe *v = sqlite3GetVdbe(pParse);
-    sqlite3VdbeSetNumCols(v, 2);
-    pParse->nMem = 2;
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", P4_STATIC);
-    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", P4_STATIC);
-    for(i=0; i<db->nDb; i++){
-      Btree *pBt;
-      Pager *pPager;
-      const char *zState = "unknown";
-      int j;
-      if( db->aDb[i].zName==0 ) continue;
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, db->aDb[i].zName, P4_STATIC);
-      pBt = db->aDb[i].pBt;
-      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
-        zState = "closed";
-      }else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0, 
-                                     SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
-         zState = azLockName[j];
-      }
-      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
-      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
+  sqlite3SelectDelete(db, pSub1);
+
+  return 1;
+}
+#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
+
+/*
+** Analyze the SELECT statement passed as an argument to see if it
+** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if 
+** it is, or 0 otherwise. At present, a query is considered to be
+** a min()/max() query if:
+**
+**   1. There is a single object in the FROM clause.
+**
+**   2. There is a single expression in the result set, and it is
+**      either min(x) or max(x), where x is a column reference.
+*/
+static u8 minMaxQuery(Select *p){
+  Expr *pExpr;
+  ExprList *pEList = p->pEList;
+
+  if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
+  pExpr = pEList->a[0].pExpr;
+  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
+  if( NEVER(ExprHasProperty(pExpr, EP_xIsSelect)) ) return 0;
+  pEList = pExpr->x.pList;
+  if( pEList==0 || pEList->nExpr!=1 ) return 0;
+  if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
+  assert( !ExprHasProperty(pExpr, EP_IntValue) );
+  if( sqlite3StrICmp(pExpr->u.zToken,"min")==0 ){
+    return WHERE_ORDERBY_MIN;
+  }else if( sqlite3StrICmp(pExpr->u.zToken,"max")==0 ){
+    return WHERE_ORDERBY_MAX;
+  }
+  return WHERE_ORDERBY_NORMAL;
+}
+
+/*
+** The select statement passed as the first argument is an aggregate query.
+** The second argment is the associated aggregate-info object. This 
+** function tests if the SELECT is of the form:
+**
+**   SELECT count(*) FROM <tbl>
+**
+** where table is a database table, not a sub-select or view. If the query
+** does match this pattern, then a pointer to the Table object representing
+** <tbl> is returned. Otherwise, 0 is returned.
+*/
+static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){
+  Table *pTab;
+  Expr *pExpr;
+
+  assert( !p->pGroupBy );
+
+  if( p->pWhere || p->pEList->nExpr!=1 
+   || p->pSrc->nSrc!=1 || p->pSrc->a[0].pSelect
+  ){
+    return 0;
+  }
+  pTab = p->pSrc->a[0].pTab;
+  pExpr = p->pEList->a[0].pExpr;
+  assert( pTab && !pTab->pSelect && pExpr );
+
+  if( IsVirtual(pTab) ) return 0;
+  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
+  if( (pAggInfo->aFunc[0].pFunc->flags&SQLITE_FUNC_COUNT)==0 ) return 0;
+  if( pExpr->flags&EP_Distinct ) return 0;
+
+  return pTab;
+}
+
+/*
+** If the source-list item passed as an argument was augmented with an
+** INDEXED BY clause, then try to locate the specified index. If there
+** was such a clause and the named index cannot be found, return 
+** SQLITE_ERROR and leave an error in pParse. Otherwise, populate 
+** pFrom->pIndex and return SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *pParse, struct SrcList_item *pFrom){
+  if( pFrom->pTab && pFrom->zIndex ){
+    Table *pTab = pFrom->pTab;
+    char *zIndex = pFrom->zIndex;
+    Index *pIdx;
+    for(pIdx=pTab->pIndex; 
+        pIdx && sqlite3StrICmp(pIdx->zName, zIndex); 
+        pIdx=pIdx->pNext
+    );
+    if( !pIdx ){
+      sqlite3ErrorMsg(pParse, "no such index: %s", zIndex, 0);
+      return SQLITE_ERROR;
     }
-  }else
-#endif
+    pFrom->pIndex = pIdx;
+  }
+  return SQLITE_OK;
+}
 
-#ifdef SQLITE_SSE
-  /*
-  ** Check to see if the sqlite_statements table exists.  Create it
-  ** if it does not.
+/*
+** This routine is a Walker callback for "expanding" a SELECT statement.
+** "Expanding" means to do the following:
+**
+**    (1)  Make sure VDBE cursor numbers have been assigned to every
+**         element of the FROM clause.
+**
+**    (2)  Fill in the pTabList->a[].pTab fields in the SrcList that 
+**         defines FROM clause.  When views appear in the FROM clause,
+**         fill pTabList->a[].pSelect with a copy of the SELECT statement
+**         that implements the view.  A copy is made of the view's SELECT
+**         statement so that we can freely modify or delete that statement
+**         without worrying about messing up the presistent representation
+**         of the view.
+**
+**    (3)  Add terms to the WHERE clause to accomodate the NATURAL keyword
+**         on joins and the ON and USING clause of joins.
+**
+**    (4)  Scan the list of columns in the result set (pEList) looking
+**         for instances of the "*" operator or the TABLE.* operator.
+**         If found, expand each "*" to be every column in every table
+**         and TABLE.* to be every column in TABLE.
+**
+*/
+static int selectExpander(Walker *pWalker, Select *p){
+  Parse *pParse = pWalker->pParse;
+  int i, j, k;
+  SrcList *pTabList;
+  ExprList *pEList;
+  struct SrcList_item *pFrom;
+  sqlite3 *db = pParse->db;
+
+  if( db->mallocFailed  ){
+    return WRC_Abort;
+  }
+  if( NEVER(p->pSrc==0) || (p->selFlags & SF_Expanded)!=0 ){
+    return WRC_Prune;
+  }
+  p->selFlags |= SF_Expanded;
+  pTabList = p->pSrc;
+  pEList = p->pEList;
+
+  /* Make sure cursor numbers have been assigned to all entries in
+  ** the FROM clause of the SELECT statement.
   */
-  if( sqlite3StrICmp(zLeft, "create_sqlite_statement_table")==0 ){
-    extern int sqlite3CreateStatementsTable(Parse*);
-    sqlite3CreateStatementsTable(pParse);
-  }else
-#endif
+  sqlite3SrcListAssignCursors(pParse, pTabList);
 
-#if SQLITE_HAS_CODEC
-  if( sqlite3StrICmp(zLeft, "key")==0 ){
-    sqlite3_key(db, zRight, strlen(zRight));
-  }else
-#endif
-#if SQLITE_HAS_CODEC || defined(SQLITE_ENABLE_CEROD)
-  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 ){
-#if SQLITE_HAS_CODEC
-    if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
-      extern void sqlite3_activate_see(const char*);
-      sqlite3_activate_see(&zRight[4]);
+  /* Look up every table named in the FROM clause of the select.  If
+  ** an entry of the FROM clause is a subquery instead of a table or view,
+  ** then create a transient table structure to describe the subquery.
+  */
+  for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
+    Table *pTab;
+    if( pFrom->pTab!=0 ){
+      /* This statement has already been prepared.  There is no need
+      ** to go further. */
+      assert( i==0 );
+      return WRC_Prune;
     }
+    if( pFrom->zName==0 ){
+#ifndef SQLITE_OMIT_SUBQUERY
+      Select *pSel = pFrom->pSelect;
+      /* A sub-query in the FROM clause of a SELECT */
+      assert( pSel!=0 );
+      assert( pFrom->pTab==0 );
+      sqlite3WalkSelect(pWalker, pSel);
+      pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
+      if( pTab==0 ) return WRC_Abort;
+      pTab->dbMem = db->lookaside.bEnabled ? db : 0;
+      pTab->nRef = 1;
+      pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
+      while( pSel->pPrior ){ pSel = pSel->pPrior; }
+      selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol);
+      pTab->iPKey = -1;
+      pTab->tabFlags |= TF_Ephemeral;
 #endif
-#ifdef SQLITE_ENABLE_CEROD
-    if( sqlite3StrNICmp(zRight, "cerod-", 6)==0 ){
-      extern void sqlite3_activate_cerod(const char*);
-      sqlite3_activate_cerod(&zRight[6]);
+    }else{
+      /* An ordinary table or view name in the FROM clause */
+      assert( pFrom->pTab==0 );
+      pFrom->pTab = pTab = 
+        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
+      if( pTab==0 ) return WRC_Abort;
+      pTab->nRef++;
+#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
+      if( pTab->pSelect || IsVirtual(pTab) ){
+        /* We reach here if the named table is a really a view */
+        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
+        assert( pFrom->pSelect==0 );
+        pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0);
+        sqlite3WalkSelect(pWalker, pFrom->pSelect);
+      }
+#endif
+    }
+
+    /* Locate the index named by the INDEXED BY clause, if any. */
+    if( sqlite3IndexedByLookup(pParse, pFrom) ){
+      return WRC_Abort;
+    }
+  }
+
+  /* Process NATURAL keywords, and ON and USING clauses of joins.
+  */
+  if( db->mallocFailed || sqliteProcessJoin(pParse, p) ){
+    return WRC_Abort;
+  }
+
+  /* For every "*" that occurs in the column list, insert the names of
+  ** all columns in all tables.  And for every TABLE.* insert the names
+  ** of all columns in TABLE.  The parser inserted a special expression
+  ** with the TK_ALL operator for each "*" that it found in the column list.
+  ** The following code just has to locate the TK_ALL expressions and expand
+  ** each one to the list of all columns in all tables.
+  **
+  ** The first loop just checks to see if there are any "*" operators
+  ** that need expanding.
+  */
+  for(k=0; k<pEList->nExpr; k++){
+    Expr *pE = pEList->a[k].pExpr;
+    if( pE->op==TK_ALL ) break;
+    assert( pE->op!=TK_DOT || pE->pRight!=0 );
+    assert( pE->op!=TK_DOT || (pE->pLeft!=0 && pE->pLeft->op==TK_ID) );
+    if( pE->op==TK_DOT && pE->pRight->op==TK_ALL ) break;
+  }
+  if( k<pEList->nExpr ){
+    /*
+    ** If we get here it means the result set contains one or more "*"
+    ** operators that need to be expanded.  Loop through each expression
+    ** in the result set and expand them one by one.
+    */
+    struct ExprList_item *a = pEList->a;
+    ExprList *pNew = 0;
+    int flags = pParse->db->flags;
+    int longNames = (flags & SQLITE_FullColNames)!=0
+                      && (flags & SQLITE_ShortColNames)==0;
+
+    for(k=0; k<pEList->nExpr; k++){
+      Expr *pE = a[k].pExpr;
+      assert( pE->op!=TK_DOT || pE->pRight!=0 );
+      if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pE->pRight->op!=TK_ALL) ){
+        /* This particular expression does not need to be expanded.
+        */
+        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr);
+        if( pNew ){
+          pNew->a[pNew->nExpr-1].zName = a[k].zName;
+          pNew->a[pNew->nExpr-1].zSpan = a[k].zSpan;
+          a[k].zName = 0;
+          a[k].zSpan = 0;
+        }
+        a[k].pExpr = 0;
+      }else{
+        /* This expression is a "*" or a "TABLE.*" and needs to be
+        ** expanded. */
+        int tableSeen = 0;      /* Set to 1 when TABLE matches */
+        char *zTName;            /* text of name of TABLE */
+        if( pE->op==TK_DOT ){
+          assert( pE->pLeft!=0 );
+          assert( !ExprHasProperty(pE->pLeft, EP_IntValue) );
+          zTName = pE->pLeft->u.zToken;
+        }else{
+          zTName = 0;
+        }
+        for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
+          Table *pTab = pFrom->pTab;
+          char *zTabName = pFrom->zAlias;
+          if( zTabName==0 ){
+            zTabName = pTab->zName;
+          }
+          if( db->mallocFailed ) break;
+          if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
+            continue;
+          }
+          tableSeen = 1;
+          for(j=0; j<pTab->nCol; j++){
+            Expr *pExpr, *pRight;
+            char *zName = pTab->aCol[j].zName;
+            char *zColname;  /* The computed column name */
+            char *zToFree;   /* Malloced string that needs to be freed */
+            Token sColname;  /* Computed column name as a token */
+
+            /* If a column is marked as 'hidden' (currently only possible
+            ** for virtual tables), do not include it in the expanded
+            ** result-set list.
+            */
+            if( IsHiddenColumn(&pTab->aCol[j]) ){
+              assert(IsVirtual(pTab));
+              continue;
+            }
+
+            if( i>0 && zTName==0 ){
+              struct SrcList_item *pLeft = &pTabList->a[i-1];
+              if( (pLeft[1].jointype & JT_NATURAL)!=0 &&
+                        columnIndex(pLeft->pTab, zName)>=0 ){
+                /* In a NATURAL join, omit the join columns from the 
+                ** table on the right */
+                continue;
+              }
+              if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){
+                /* In a join with a USING clause, omit columns in the
+                ** using clause from the table on the right. */
+                continue;
+              }
+            }
+            pRight = sqlite3Expr(db, TK_ID, zName);
+            zColname = zName;
+            zToFree = 0;
+            if( longNames || pTabList->nSrc>1 ){
+              Expr *pLeft;
+              pLeft = sqlite3Expr(db, TK_ID, zTabName);
+              pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
+              if( longNames ){
+                zColname = sqlite3MPrintf(db, "%s.%s", zTabName, zName);
+                zToFree = zColname;
+              }
+            }else{
+              pExpr = pRight;
+            }
+            pNew = sqlite3ExprListAppend(pParse, pNew, pExpr);
+            sColname.z = zColname;
+            sColname.n = sqlite3Strlen30(zColname);
+            sqlite3ExprListSetName(pParse, pNew, &sColname, 0);
+            sqlite3DbFree(db, zToFree);
+          }
+        }
+        if( !tableSeen ){
+          if( zTName ){
+            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
+          }else{
+            sqlite3ErrorMsg(pParse, "no tables specified");
+          }
+        }
+      }
     }
-#endif
+    sqlite3ExprListDelete(db, pEList);
+    p->pEList = pNew;
+  }
+#if SQLITE_MAX_COLUMN
+  if( p->pEList && p->pEList->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
+    sqlite3ErrorMsg(pParse, "too many columns in result set");
   }
 #endif
+  return WRC_Continue;
+}
 
-  {}
+/*
+** No-op routine for the parse-tree walker.
+**
+** When this routine is the Walker.xExprCallback then expression trees
+** are walked without any actions being taken at each node.  Presumably,
+** when this routine is used for Walker.xExprCallback then 
+** Walker.xSelectCallback is set to do something useful for every 
+** subquery in the parser tree.
+*/
+static int exprWalkNoop(Walker *NotUsed, Expr *NotUsed2){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  return WRC_Continue;
+}
 
-  if( v ){
-    /* Code an OP_Expire at the end of each PRAGMA program to cause
-    ** the VDBE implementing the pragma to expire. Most (all?) pragmas
-    ** are only valid for a single execution.
-    */
-    sqlite3VdbeAddOp2(v, OP_Expire, 1, 0);
+/*
+** This routine "expands" a SELECT statement and all of its subqueries.
+** For additional information on what it means to "expand" a SELECT
+** statement, see the comment on the selectExpand worker callback above.
+**
+** Expanding a SELECT statement is the first step in processing a
+** SELECT statement.  The SELECT statement must be expanded before
+** name resolution is performed.
+**
+** If anything goes wrong, an error message is written into pParse.
+** The calling function can detect the problem by looking at pParse->nErr
+** and/or pParse->db->mallocFailed.
+*/
+static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){
+  Walker w;
+  w.xSelectCallback = selectExpander;
+  w.xExprCallback = exprWalkNoop;
+  w.pParse = pParse;
+  sqlite3WalkSelect(&w, pSelect);
+}
 
-    /*
-    ** Reset the safety level, in case the fullfsync flag or synchronous
-    ** setting changed.
-    */
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-    if( db->autoCommit ){
-      sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
-                 (db->flags&SQLITE_FullFSync)!=0);
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** This is a Walker.xSelectCallback callback for the sqlite3SelectTypeInfo()
+** interface.
+**
+** For each FROM-clause subquery, add Column.zType and Column.zColl
+** information to the Table structure that represents the result set
+** of that subquery.
+**
+** The Table structure that represents the result set was constructed
+** by selectExpander() but the type and collation information was omitted
+** at that point because identifiers had not yet been resolved.  This
+** routine is called after identifier resolution.
+*/
+static int selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){
+  Parse *pParse;
+  int i;
+  SrcList *pTabList;
+  struct SrcList_item *pFrom;
+
+  assert( p->selFlags & SF_Resolved );
+  assert( (p->selFlags & SF_HasTypeInfo)==0 );
+  p->selFlags |= SF_HasTypeInfo;
+  pParse = pWalker->pParse;
+  pTabList = p->pSrc;
+  for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
+    Table *pTab = pFrom->pTab;
+    if( ALWAYS(pTab!=0) && (pTab->tabFlags & TF_Ephemeral)!=0 ){
+      /* A sub-query in the FROM clause of a SELECT */
+      Select *pSel = pFrom->pSelect;
+      assert( pSel );
+      while( pSel->pPrior ) pSel = pSel->pPrior;
+      selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSel);
     }
-#endif
   }
-pragma_out:
-  sqlite3_free(zLeft);
-  sqlite3_free(zRight);
+  return WRC_Continue;
 }
+#endif
 
-#endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */
 
-/************** End of pragma.c **********************************************/
-/************** Begin file prepare.c *****************************************/
 /*
-** 2005 May 25
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** This routine adds datatype and collating sequence information to
+** the Table structures of all FROM-clause subqueries in a
+** SELECT statement.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains the implementation of the sqlite3_prepare()
-** interface, and routines that contribute to loading the database schema
-** from disk.
-**
-** $Id: prepare.c,v 1.83 2008/04/03 14:36:26 danielk1977 Exp $
+** Use this routine after name resolution.
 */
+static void sqlite3SelectAddTypeInfo(Parse *pParse, Select *pSelect){
+#ifndef SQLITE_OMIT_SUBQUERY
+  Walker w;
+  w.xSelectCallback = selectAddSubqueryTypeInfo;
+  w.xExprCallback = exprWalkNoop;
+  w.pParse = pParse;
+  sqlite3WalkSelect(&w, pSelect);
+#endif
+}
+
 
 /*
-** Fill the InitData structure with an error message that indicates
-** that the database is corrupt.
+** This routine sets of a SELECT statement for processing.  The
+** following is accomplished:
+**
+**     *  VDBE Cursor numbers are assigned to all FROM-clause terms.
+**     *  Ephemeral Table objects are created for all FROM-clause subqueries.
+**     *  ON and USING clauses are shifted into WHERE statements
+**     *  Wildcards "*" and "TABLE.*" in result sets are expanded.
+**     *  Identifiers in expression are matched to tables.
+**
+** This routine acts recursively on all subqueries within the SELECT.
 */
-static void corruptSchema(
-  InitData *pData,     /* Initialization context */
-  const char *zObj,    /* Object being parsed at the point of error */
-  const char *zExtra   /* Error information */
+SQLITE_PRIVATE void sqlite3SelectPrep(
+  Parse *pParse,         /* The parser context */
+  Select *p,             /* The SELECT statement being coded. */
+  NameContext *pOuterNC  /* Name context for container */
 ){
-  if( !pData->db->mallocFailed ){
-    if( zObj==0 ) zObj = "?";
-    sqlite3SetString(pData->pzErrMsg, "malformed database schema (",  zObj, ")",
-       zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
-  }
-  pData->rc = SQLITE_CORRUPT;
+  sqlite3 *db;
+  if( NEVER(p==0) ) return;
+  db = pParse->db;
+  if( p->selFlags & SF_HasTypeInfo ) return;
+  sqlite3SelectExpand(pParse, p);
+  if( pParse->nErr || db->mallocFailed ) return;
+  sqlite3ResolveSelectNames(pParse, p, pOuterNC);
+  if( pParse->nErr || db->mallocFailed ) return;
+  sqlite3SelectAddTypeInfo(pParse, p);
 }
 
 /*
-** This is the callback routine for the code that initializes the
-** database.  See sqlite3Init() below for additional information.
-** This routine is also called from the OP_ParseSchema opcode of the VDBE.
-**
-** Each callback contains the following information:
-**
-**     argv[0] = name of thing being created
-**     argv[1] = root page number for table or index. 0 for trigger or view.
-**     argv[2] = SQL text for the CREATE statement.
+** Reset the aggregate accumulator.
 **
+** The aggregate accumulator is a set of memory cells that hold
+** intermediate results while calculating an aggregate.  This
+** routine simply stores NULLs in all of those memory cells.
 */
-SQLITE_PRIVATE int sqlite3InitCallback(void *pInit, int argc, char **argv, char **azColName){
-  InitData *pData = (InitData*)pInit;
-  sqlite3 *db = pData->db;
-  int iDb = pData->iDb;
-
-  assert( sqlite3_mutex_held(db->mutex) );
-  pData->rc = SQLITE_OK;
-  DbClearProperty(db, iDb, DB_Empty);
-  if( db->mallocFailed ){
-    corruptSchema(pData, argv[0], 0);
-    return SQLITE_NOMEM;
+static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct AggInfo_func *pFunc;
+  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
+    return;
   }
-
-  assert( argc==3 );
-  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
-  if( argv[1]==0 ){
-    corruptSchema(pData, argv[0], 0);
-    return 1;
+  for(i=0; i<pAggInfo->nColumn; i++){
+    sqlite3VdbeAddOp2(v, OP_Null, 0, pAggInfo->aCol[i].iMem);
   }
-  assert( iDb>=0 && iDb<db->nDb );
-  if( argv[2] && argv[2][0] ){
-    /* Call the parser to process a CREATE TABLE, INDEX or VIEW.
-    ** But because db->init.busy is set to 1, no VDBE code is generated
-    ** or executed.  All the parser does is build the internal data
-    ** structures that describe the table, index, or view.
-    */
-    char *zErr;
-    int rc;
-    assert( db->init.busy );
-    db->init.iDb = iDb;
-    db->init.newTnum = atoi(argv[1]);
-    rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
-    db->init.iDb = 0;
-    assert( rc!=SQLITE_OK || zErr==0 );
-    if( SQLITE_OK!=rc ){
-      pData->rc = rc;
-      if( rc==SQLITE_NOMEM ){
-        db->mallocFailed = 1;
-      }else if( rc!=SQLITE_INTERRUPT ){
-        corruptSchema(pData, argv[0], zErr);
+  for(pFunc=pAggInfo->aFunc, i=0; i<pAggInfo->nFunc; i++, pFunc++){
+    sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem);
+    if( pFunc->iDistinct>=0 ){
+      Expr *pE = pFunc->pExpr;
+      assert( !ExprHasProperty(pE, EP_xIsSelect) );
+      if( pE->x.pList==0 || pE->x.pList->nExpr!=1 ){
+        sqlite3ErrorMsg(pParse, "DISTINCT aggregates must have exactly one "
+           "argument");
+        pFunc->iDistinct = -1;
+      }else{
+        KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->x.pList);
+        sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0,
+                          (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
       }
-      sqlite3_free(zErr);
-      return 1;
-    }
-  }else if( argv[0]==0 ){
-    corruptSchema(pData, 0, 0);
-  }else{
-    /* If the SQL column is blank it means this is an index that
-    ** was created to be the PRIMARY KEY or to fulfill a UNIQUE
-    ** constraint for a CREATE TABLE.  The index should have already
-    ** been created when we processed the CREATE TABLE.  All we have
-    ** to do here is record the root page number for that index.
-    */
-    Index *pIndex;
-    pIndex = sqlite3FindIndex(db, argv[0], db->aDb[iDb].zName);
-    if( pIndex==0 || pIndex->tnum!=0 ){
-      /* This can occur if there exists an index on a TEMP table which
-      ** has the same name as another index on a permanent index.  Since
-      ** the permanent table is hidden by the TEMP table, we can also
-      ** safely ignore the index on the permanent table.
-      */
-      /* Do Nothing */;
-    }else{
-      pIndex->tnum = atoi(argv[1]);
     }
   }
-  return 0;
 }
 
 /*
-** Attempt to read the database schema and initialize internal
-** data structures for a single database file.  The index of the
-** database file is given by iDb.  iDb==0 is used for the main
-** database.  iDb==1 should never be used.  iDb>=2 is used for
-** auxiliary databases.  Return one of the SQLITE_ error codes to
-** indicate success or failure.
+** Invoke the OP_AggFinalize opcode for every aggregate function
+** in the AggInfo structure.
 */
-static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
-  int rc;
-  BtCursor *curMain;
-  int size;
-  Table *pTab;
-  Db *pDb;
-  char const *azArg[4];
-  int meta[10];
-  InitData initData;
-  char const *zMasterSchema;
-  char const *zMasterName = SCHEMA_TABLE(iDb);
-
-  /*
-  ** The master database table has a structure like this
-  */
-  static const char master_schema[] = 
-     "CREATE TABLE sqlite_master(\n"
-     "  type text,\n"
-     "  name text,\n"
-     "  tbl_name text,\n"
-     "  rootpage integer,\n"
-     "  sql text\n"
-     ")"
-  ;
-#ifndef SQLITE_OMIT_TEMPDB
-  static const char temp_master_schema[] = 
-     "CREATE TEMP TABLE sqlite_temp_master(\n"
-     "  type text,\n"
-     "  name text,\n"
-     "  tbl_name text,\n"
-     "  rootpage integer,\n"
-     "  sql text\n"
-     ")"
-  ;
-#else
-  #define temp_master_schema 0
-#endif
-
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( db->aDb[iDb].pSchema );
-  assert( sqlite3_mutex_held(db->mutex) );
-  assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
-
-  /* zMasterSchema and zInitScript are set to point at the master schema
-  ** and initialisation script appropriate for the database being
-  ** initialised. zMasterName is the name of the master table.
-  */
-  if( !OMIT_TEMPDB && iDb==1 ){
-    zMasterSchema = temp_master_schema;
-  }else{
-    zMasterSchema = master_schema;
-  }
-  zMasterName = SCHEMA_TABLE(iDb);
-
-  /* Construct the schema tables.  */
-  azArg[0] = zMasterName;
-  azArg[1] = "1";
-  azArg[2] = zMasterSchema;
-  azArg[3] = 0;
-  initData.db = db;
-  initData.iDb = iDb;
-  initData.pzErrMsg = pzErrMsg;
-  (void)sqlite3SafetyOff(db);
-  rc = sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
-  (void)sqlite3SafetyOn(db);
-  if( rc ){
-    rc = initData.rc;
-    goto error_out;
-  }
-  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
-  if( pTab ){
-    pTab->readOnly = 1;
+static void finalizeAggFunctions(Parse *pParse, AggInfo *pAggInfo){
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct AggInfo_func *pF;
+  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
+    ExprList *pList = pF->pExpr->x.pList;
+    assert( !ExprHasProperty(pF->pExpr, EP_xIsSelect) );
+    sqlite3VdbeAddOp4(v, OP_AggFinal, pF->iMem, pList ? pList->nExpr : 0, 0,
+                      (void*)pF->pFunc, P4_FUNCDEF);
   }
+}
 
-  /* Create a cursor to hold the database open
-  */
-  pDb = &db->aDb[iDb];
-  if( pDb->pBt==0 ){
-    if( !OMIT_TEMPDB && iDb==1 ){
-      DbSetProperty(db, 1, DB_SchemaLoaded);
-    }
-    return SQLITE_OK;
-  }
-  curMain = sqlite3MallocZero(sqlite3BtreeCursorSize());
-  if( !curMain ){
-    rc = SQLITE_NOMEM;
-    goto error_out;
-  }
-  sqlite3BtreeEnter(pDb->pBt);
-  rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, curMain);
-  if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
-    sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
-    goto leave_error_out;
-  }
+/*
+** Update the accumulator memory cells for an aggregate based on
+** the current cursor position.
+*/
+static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct AggInfo_func *pF;
+  struct AggInfo_col *pC;
 
-  /* Get the database meta information.
-  **
-  ** Meta values are as follows:
-  **    meta[0]   Schema cookie.  Changes with each schema change.
-  **    meta[1]   File format of schema layer.
-  **    meta[2]   Size of the page cache.
-  **    meta[3]   Use freelist if 0.  Autovacuum if greater than zero.
-  **    meta[4]   Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
-  **    meta[5]   The user cookie. Used by the application.
-  **    meta[6]   Incremental-vacuum flag.
-  **    meta[7]
-  **    meta[8]
-  **    meta[9]
-  **
-  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
-  ** the possible values of meta[4].
-  */
-  if( rc==SQLITE_OK ){
-    int i;
-    for(i=0; rc==SQLITE_OK && i<sizeof(meta)/sizeof(meta[0]); i++){
-      rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
+  pAggInfo->directMode = 1;
+  sqlite3ExprCacheClear(pParse);
+  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
+    int nArg;
+    int addrNext = 0;
+    int regAgg;
+    ExprList *pList = pF->pExpr->x.pList;
+    assert( !ExprHasProperty(pF->pExpr, EP_xIsSelect) );
+    if( pList ){
+      nArg = pList->nExpr;
+      regAgg = sqlite3GetTempRange(pParse, nArg);
+      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
+    }else{
+      nArg = 0;
+      regAgg = 0;
     }
-    if( rc ){
-      sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
-      goto leave_error_out;
+    if( pF->iDistinct>=0 ){
+      addrNext = sqlite3VdbeMakeLabel(v);
+      assert( nArg==1 );
+      codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg);
     }
-  }else{
-    memset(meta, 0, sizeof(meta));
-  }
-  pDb->pSchema->schema_cookie = meta[0];
-
-  /* If opening a non-empty database, check the text encoding. For the
-  ** main database, set sqlite3.enc to the encoding of the main database.
-  ** For an attached db, it is an error if the encoding is not the same
-  ** as sqlite3.enc.
-  */
-  if( meta[4] ){  /* text encoding */
-    if( iDb==0 ){
-      /* If opening the main database, set ENC(db). */
-      ENC(db) = (u8)meta[4];
-      db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
-    }else{
-      /* If opening an attached database, the encoding much match ENC(db) */
-      if( meta[4]!=ENC(db) ){
-        sqlite3SetString(pzErrMsg, "attached databases must use the same"
-            " text encoding as main database", (char*)0);
-        rc = SQLITE_ERROR;
-        goto leave_error_out;
+    if( pF->pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
+      CollSeq *pColl = 0;
+      struct ExprList_item *pItem;
+      int j;
+      assert( pList!=0 );  /* pList!=0 if pF->pFunc has NEEDCOLL */
+      for(j=0, pItem=pList->a; !pColl && j<nArg; j++, pItem++){
+        pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
+      }
+      if( !pColl ){
+        pColl = pParse->db->pDfltColl;
       }
+      sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
+    }
+    sqlite3VdbeAddOp4(v, OP_AggStep, 0, regAgg, pF->iMem,
+                      (void*)pF->pFunc, P4_FUNCDEF);
+    sqlite3VdbeChangeP5(v, (u8)nArg);
+    sqlite3ReleaseTempRange(pParse, regAgg, nArg);
+    sqlite3ExprCacheAffinityChange(pParse, regAgg, nArg);
+    if( addrNext ){
+      sqlite3VdbeResolveLabel(v, addrNext);
+      sqlite3ExprCacheClear(pParse);
     }
-  }else{
-    DbSetProperty(db, iDb, DB_Empty);
   }
-  pDb->pSchema->enc = ENC(db);
+  for(i=0, pC=pAggInfo->aCol; i<pAggInfo->nAccumulator; i++, pC++){
+    sqlite3ExprCode(pParse, pC->pExpr, pC->iMem);
+  }
+  pAggInfo->directMode = 0;
+  sqlite3ExprCacheClear(pParse);
+}
+
+/*
+** Generate code for the SELECT statement given in the p argument.  
+**
+** The results are distributed in various ways depending on the
+** contents of the SelectDest structure pointed to by argument pDest
+** as follows:
+**
+**     pDest->eDest    Result
+**     ------------    -------------------------------------------
+**     SRT_Output      Generate a row of output (using the OP_ResultRow
+**                     opcode) for each row in the result set.
+**
+**     SRT_Mem         Only valid if the result is a single column.
+**                     Store the first column of the first result row
+**                     in register pDest->iParm then abandon the rest
+**                     of the query.  This destination implies "LIMIT 1".
+**
+**     SRT_Set         The result must be a single column.  Store each
+**                     row of result as the key in table pDest->iParm. 
+**                     Apply the affinity pDest->affinity before storing
+**                     results.  Used to implement "IN (SELECT ...)".
+**
+**     SRT_Union       Store results as a key in a temporary table pDest->iParm.
+**
+**     SRT_Except      Remove results from the temporary table pDest->iParm.
+**
+**     SRT_Table       Store results in temporary table pDest->iParm.
+**                     This is like SRT_EphemTab except that the table
+**                     is assumed to already be open.
+**
+**     SRT_EphemTab    Create an temporary table pDest->iParm and store
+**                     the result there. The cursor is left open after
+**                     returning.  This is like SRT_Table except that
+**                     this destination uses OP_OpenEphemeral to create
+**                     the table first.
+**
+**     SRT_Coroutine   Generate a co-routine that returns a new row of
+**                     results each time it is invoked.  The entry point
+**                     of the co-routine is stored in register pDest->iParm.
+**
+**     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
+**                     set is not empty.
+**
+**     SRT_Discard     Throw the results away.  This is used by SELECT
+**                     statements within triggers whose only purpose is
+**                     the side-effects of functions.
+**
+** This routine returns the number of errors.  If any errors are
+** encountered, then an appropriate error message is left in
+** pParse->zErrMsg.
+**
+** This routine does NOT free the Select structure passed in.  The
+** calling function needs to do that.
+*/
+SQLITE_PRIVATE int sqlite3Select(
+  Parse *pParse,         /* The parser context */
+  Select *p,             /* The SELECT statement being coded. */
+  SelectDest *pDest      /* What to do with the query results */
+){
+  int i, j;              /* Loop counters */
+  WhereInfo *pWInfo;     /* Return from sqlite3WhereBegin() */
+  Vdbe *v;               /* The virtual machine under construction */
+  int isAgg;             /* True for select lists like "count(*)" */
+  ExprList *pEList;      /* List of columns to extract. */
+  SrcList *pTabList;     /* List of tables to select from */
+  Expr *pWhere;          /* The WHERE clause.  May be NULL */
+  ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
+  ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
+  Expr *pHaving;         /* The HAVING clause.  May be NULL */
+  int isDistinct;        /* True if the DISTINCT keyword is present */
+  int distinct;          /* Table to use for the distinct set */
+  int rc = 1;            /* Value to return from this function */
+  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
+  AggInfo sAggInfo;      /* Information used by aggregate queries */
+  int iEnd;              /* Address of the end of the query */
+  sqlite3 *db;           /* The database connection */
 
-  size = meta[2];
-  if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
-  if( size<0 ) size = -size;
-  pDb->pSchema->cache_size = size;
-  sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+  db = pParse->db;
+  if( p==0 || db->mallocFailed || pParse->nErr ){
+    return 1;
+  }
+  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
+  memset(&sAggInfo, 0, sizeof(sAggInfo));
 
-  /*
-  ** file_format==1    Version 3.0.0.
-  ** file_format==2    Version 3.1.3.  // ALTER TABLE ADD COLUMN
-  ** file_format==3    Version 3.1.4.  // ditto but with non-NULL defaults
-  ** file_format==4    Version 3.3.0.  // DESC indices.  Boolean constants
-  */
-  pDb->pSchema->file_format = meta[1];
-  if( pDb->pSchema->file_format==0 ){
-    pDb->pSchema->file_format = 1;
+  if( IgnorableOrderby(pDest) ){
+    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
+           pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard);
+    /* If ORDER BY makes no difference in the output then neither does
+    ** DISTINCT so it can be removed too. */
+    sqlite3ExprListDelete(db, p->pOrderBy);
+    p->pOrderBy = 0;
+    p->selFlags &= ~SF_Distinct;
   }
-  if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
-    sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
-    rc = SQLITE_ERROR;
-    goto leave_error_out;
+  sqlite3SelectPrep(pParse, p, 0);
+  pOrderBy = p->pOrderBy;
+  pTabList = p->pSrc;
+  pEList = p->pEList;
+  if( pParse->nErr || db->mallocFailed ){
+    goto select_end;
   }
+  isAgg = (p->selFlags & SF_Aggregate)!=0;
+  assert( pEList!=0 );
 
-  /* Ticket #2804:  When we open a database in the newer file format,
-  ** clear the legacy_file_format pragma flag so that a VACUUM will
-  ** not downgrade the database and thus invalidate any descending
-  ** indices that the user might have created.
+  /* Begin generating code.
   */
-  if( iDb==0 && meta[1]>=4 ){
-    db->flags &= ~SQLITE_LegacyFileFmt;
-  }
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ) goto select_end;
 
-  /* Read the schema information out of the schema tables
+  /* Generate code for all sub-queries in the FROM clause
   */
-  assert( db->init.busy );
-  if( rc==SQLITE_EMPTY ){
-    /* For an empty database, there is nothing to read */
-    rc = SQLITE_OK;
-  }else{
-    char *zSql;
-    zSql = sqlite3MPrintf(db, 
-        "SELECT name, rootpage, sql FROM '%q'.%s",
-        db->aDb[iDb].zName, zMasterName);
-    (void)sqlite3SafetyOff(db);
-#ifndef SQLITE_OMIT_AUTHORIZATION
-    {
-      int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
-      xAuth = db->xAuth;
-      db->xAuth = 0;
-#endif
-      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
-#ifndef SQLITE_OMIT_AUTHORIZATION
-      db->xAuth = xAuth;
-    }
-#endif
-    if( rc==SQLITE_ABORT ) rc = initData.rc;
-    (void)sqlite3SafetyOn(db);
-    sqlite3_free(zSql);
-#ifndef SQLITE_OMIT_ANALYZE
-    if( rc==SQLITE_OK ){
-      sqlite3AnalysisLoad(db, iDb);
-    }
-#endif
-  }
-  if( db->mallocFailed ){
-    /* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
-    rc = SQLITE_NOMEM;
-    sqlite3ResetInternalSchema(db, 0);
-  }
-  if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
-    /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
-    ** the schema loaded, even if errors occured. In this situation the 
-    ** current sqlite3_prepare() operation will fail, but the following one
-    ** will attempt to compile the supplied statement against whatever subset
-    ** of the schema was loaded before the error occured. The primary
-    ** purpose of this is to allow access to the sqlite_master table
-    ** even when its contents have been corrupted.
-    */
-    DbSetProperty(db, iDb, DB_SchemaLoaded);
-    rc = SQLITE_OK;
-  }
+#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
+  for(i=0; !p->pPrior && i<pTabList->nSrc; i++){
+    struct SrcList_item *pItem = &pTabList->a[i];
+    SelectDest dest;
+    Select *pSub = pItem->pSelect;
+    int isAggSub;
 
-  /* Jump here for an error that occurs after successfully allocating
-  ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
-  ** before that point, jump to error_out.
-  */
-leave_error_out:
-  sqlite3BtreeCloseCursor(curMain);
-  sqlite3_free(curMain);
-  sqlite3BtreeLeave(pDb->pBt);
+    if( pSub==0 || pItem->isPopulated ) continue;
 
-error_out:
-  if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
-    db->mallocFailed = 1;
-  }
-  return rc;
-}
+    /* Increment Parse.nHeight by the height of the largest expression
+    ** tree refered to by this, the parent select. The child select
+    ** may contain expression trees of at most
+    ** (SQLITE_MAX_EXPR_DEPTH-Parse.nHeight) height. This is a bit
+    ** more conservative than necessary, but much easier than enforcing
+    ** an exact limit.
+    */
+    pParse->nHeight += sqlite3SelectExprHeight(p);
 
-/*
-** Initialize all database files - the main database file, the file
-** used to store temporary tables, and any additional database files
-** created using ATTACH statements.  Return a success code.  If an
-** error occurs, write an error message into *pzErrMsg.
-**
-** After a database is initialized, the DB_SchemaLoaded bit is set
-** bit is set in the flags field of the Db structure. If the database
-** file was of zero-length, then the DB_Empty flag is also set.
-*/
-SQLITE_PRIVATE int sqlite3Init(sqlite3 *db, char **pzErrMsg){
-  int i, rc;
-  int commit_internal = !(db->flags&SQLITE_InternChanges);
-  
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( db->init.busy ) return SQLITE_OK;
-  rc = SQLITE_OK;
-  db->init.busy = 1;
-  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
-    if( DbHasProperty(db, i, DB_SchemaLoaded) || i==1 ) continue;
-    rc = sqlite3InitOne(db, i, pzErrMsg);
-    if( rc ){
-      sqlite3ResetInternalSchema(db, i);
+    /* Check to see if the subquery can be absorbed into the parent. */
+    isAggSub = (pSub->selFlags & SF_Aggregate)!=0;
+    if( flattenSubquery(pParse, p, i, isAgg, isAggSub) ){
+      if( isAggSub ){
+        isAgg = 1;
+        p->selFlags |= SF_Aggregate;
+      }
+      i = -1;
+    }else{
+      sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
+      assert( pItem->isPopulated==0 );
+      sqlite3Select(pParse, pSub, &dest);
+      pItem->isPopulated = 1;
+    }
+    if( /*pParse->nErr ||*/ db->mallocFailed ){
+      goto select_end;
+    }
+    pParse->nHeight -= sqlite3SelectExprHeight(p);
+    pTabList = p->pSrc;
+    if( !IgnorableOrderby(pDest) ){
+      pOrderBy = p->pOrderBy;
     }
   }
+  pEList = p->pEList;
+#endif
+  pWhere = p->pWhere;
+  pGroupBy = p->pGroupBy;
+  pHaving = p->pHaving;
+  isDistinct = (p->selFlags & SF_Distinct)!=0;
 
-  /* Once all the other databases have been initialised, load the schema
-  ** for the TEMP database. This is loaded last, as the TEMP database
-  ** schema may contain references to objects in other databases.
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
+  /* If there is are a sequence of queries, do the earlier ones first.
   */
-#ifndef SQLITE_OMIT_TEMPDB
-  if( rc==SQLITE_OK && db->nDb>1 && !DbHasProperty(db, 1, DB_SchemaLoaded) ){
-    rc = sqlite3InitOne(db, 1, pzErrMsg);
-    if( rc ){
-      sqlite3ResetInternalSchema(db, 1);
+  if( p->pPrior ){
+    if( p->pRightmost==0 ){
+      Select *pLoop, *pRight = 0;
+      int cnt = 0;
+      int mxSelect;
+      for(pLoop=p; pLoop; pLoop=pLoop->pPrior, cnt++){
+        pLoop->pRightmost = p;
+        pLoop->pNext = pRight;
+        pRight = pLoop;
+      }
+      mxSelect = db->aLimit[SQLITE_LIMIT_COMPOUND_SELECT];
+      if( mxSelect && cnt>mxSelect ){
+        sqlite3ErrorMsg(pParse, "too many terms in compound SELECT");
+        return 1;
+      }
     }
+    return multiSelect(pParse, p, pDest);
   }
 #endif
 
-  db->init.busy = 0;
-  if( rc==SQLITE_OK && commit_internal ){
-    sqlite3CommitInternalChanges(db);
+  /* If writing to memory or generating a set
+  ** only a single column may be output.
+  */
+#ifndef SQLITE_OMIT_SUBQUERY
+  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
+    goto select_end;
   }
+#endif
 
-  return rc; 
-}
-
-/*
-** This routine is a no-op if the database schema is already initialised.
-** Otherwise, the schema is loaded. An error code is returned.
-*/
-SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse){
-  int rc = SQLITE_OK;
-  sqlite3 *db = pParse->db;
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( !db->init.busy ){
-    rc = sqlite3Init(db, &pParse->zErrMsg);
-  }
-  if( rc!=SQLITE_OK ){
-    pParse->rc = rc;
-    pParse->nErr++;
+  /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
+  ** GROUP BY might use an index, DISTINCT never does.
+  */
+  assert( p->pGroupBy==0 || (p->selFlags & SF_Aggregate)!=0 );
+  if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ){
+    p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0);
+    pGroupBy = p->pGroupBy;
+    p->selFlags &= ~SF_Distinct;
+    isDistinct = 0;
   }
-  return rc;
-}
-
-
-/*
-** Check schema cookies in all databases.  If any cookie is out
-** of date, return 0.  If all schema cookies are current, return 1.
-*/
-static int schemaIsValid(sqlite3 *db){
-  int iDb;
-  int rc;
-  BtCursor *curTemp;
-  int cookie;
-  int allOk = 1;
 
-  curTemp = (BtCursor *)sqlite3_malloc(sqlite3BtreeCursorSize());
-  if( curTemp ){
-    assert( sqlite3_mutex_held(db->mutex) );
-    for(iDb=0; allOk && iDb<db->nDb; iDb++){
-      Btree *pBt;
-      pBt = db->aDb[iDb].pBt;
-      if( pBt==0 ) continue;
-      memset(curTemp, 0, sqlite3BtreeCursorSize());
-      rc = sqlite3BtreeCursor(pBt, MASTER_ROOT, 0, 0, curTemp);
-      if( rc==SQLITE_OK ){
-        rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&cookie);
-        if( rc==SQLITE_OK && cookie!=db->aDb[iDb].pSchema->schema_cookie ){
-          allOk = 0;
-        }
-        sqlite3BtreeCloseCursor(curTemp);
-      }
-      if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
-        db->mallocFailed = 1;
-      }
-    }
-    sqlite3_free(curTemp);
+  /* If there is an ORDER BY clause, then this sorting
+  ** index might end up being unused if the data can be 
+  ** extracted in pre-sorted order.  If that is the case, then the
+  ** OP_OpenEphemeral instruction will be changed to an OP_Noop once
+  ** we figure out that the sorting index is not needed.  The addrSortIndex
+  ** variable is used to facilitate that change.
+  */
+  if( pOrderBy ){
+    KeyInfo *pKeyInfo;
+    pKeyInfo = keyInfoFromExprList(pParse, pOrderBy);
+    pOrderBy->iECursor = pParse->nTab++;
+    p->addrOpenEphm[2] = addrSortIndex =
+      sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
+                           pOrderBy->iECursor, pOrderBy->nExpr+2, 0,
+                           (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
   }else{
-    allOk = 0;
-    db->mallocFailed = 1;
+    addrSortIndex = -1;
   }
 
-  return allOk;
-}
-
-/*
-** Convert a schema pointer into the iDb index that indicates
-** which database file in db->aDb[] the schema refers to.
-**
-** If the same database is attached more than once, the first
-** attached database is returned.
-*/
-SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *pSchema){
-  int i = -1000000;
-
-  /* If pSchema is NULL, then return -1000000. This happens when code in 
-  ** expr.c is trying to resolve a reference to a transient table (i.e. one
-  ** created by a sub-select). In this case the return value of this 
-  ** function should never be used.
-  **
-  ** We return -1000000 instead of the more usual -1 simply because using
-  ** -1000000 as incorrectly using -1000000 index into db->aDb[] is much 
-  ** more likely to cause a segfault than -1 (of course there are assert()
-  ** statements too, but it never hurts to play the odds).
+  /* If the output is destined for a temporary table, open that table.
   */
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( pSchema ){
-    for(i=0; i<db->nDb; i++){
-      if( db->aDb[i].pSchema==pSchema ){
-        break;
-      }
-    }
-    assert( i>=0 &&i>=0 &&  i<db->nDb );
+  if( pDest->eDest==SRT_EphemTab ){
+    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
   }
-  return i;
-}
-
-/*
-** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
-*/
-static int sqlite3Prepare(
-  sqlite3 *db,              /* Database handle. */
-  const char *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  int saveSqlFlag,          /* True to copy SQL text into the sqlite3_stmt */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const char **pzTail       /* OUT: End of parsed string */
-){
-  Parse sParse;
-  char *zErrMsg = 0;
-  int rc = SQLITE_OK;
-  int i;
 
-  assert( ppStmt );
-  *ppStmt = 0;
-  if( sqlite3SafetyOn(db) ){
-    return SQLITE_MISUSE;
-  }
-  assert( !db->mallocFailed );
-  assert( sqlite3_mutex_held(db->mutex) );
+  /* Set the limiter.
+  */
+  iEnd = sqlite3VdbeMakeLabel(v);
+  computeLimitRegisters(pParse, p, iEnd);
 
-  /* If any attached database schemas are locked, do not proceed with
-  ** compilation. Instead return SQLITE_LOCKED immediately.
+  /* Open a virtual index to use for the distinct set.
   */
-  for(i=0; i<db->nDb; i++) {
-    Btree *pBt = db->aDb[i].pBt;
-    if( pBt ){
-      int rc;
-      rc = sqlite3BtreeSchemaLocked(pBt);
-      if( rc ){
-        const char *zDb = db->aDb[i].zName;
-        sqlite3Error(db, SQLITE_LOCKED, "database schema is locked: %s", zDb);
-        (void)sqlite3SafetyOff(db);
-        return SQLITE_LOCKED;
-      }
-    }
-  }
-  
-  memset(&sParse, 0, sizeof(sParse));
-  sParse.db = db;
-  if( nBytes>=0 && zSql[nBytes-1]!=0 ){
-    char *zSqlCopy;
-    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
-    if( nBytes>mxLen ){
-      sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
-      (void)sqlite3SafetyOff(db);
-      return SQLITE_TOOBIG;
-    }
-    zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
-    if( zSqlCopy ){
-      sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
-      sqlite3_free(zSqlCopy);
-      sParse.zTail = &zSql[sParse.zTail-zSqlCopy];
-    }else{
-      sParse.zTail = &zSql[nBytes];
-    }
+  if( isDistinct ){
+    KeyInfo *pKeyInfo;
+    assert( isAgg || pGroupBy );
+    distinct = pParse->nTab++;
+    pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
+    sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
+                        (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
   }else{
-    sqlite3RunParser(&sParse, zSql, &zErrMsg);
+    distinct = -1;
   }
 
-  if( db->mallocFailed ){
-    sParse.rc = SQLITE_NOMEM;
-  }
-  if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK;
-  if( sParse.checkSchema && !schemaIsValid(db) ){
-    sParse.rc = SQLITE_SCHEMA;
-  }
-  if( sParse.rc==SQLITE_SCHEMA ){
-    sqlite3ResetInternalSchema(db, 0);
-  }
-  if( db->mallocFailed ){
-    sParse.rc = SQLITE_NOMEM;
-  }
-  if( pzTail ){
-    *pzTail = sParse.zTail;
-  }
-  rc = sParse.rc;
+  /* Aggregate and non-aggregate queries are handled differently */
+  if( !isAgg && pGroupBy==0 ){
+    /* This case is for non-aggregate queries
+    ** Begin the database scan
+    */
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy, 0);
+    if( pWInfo==0 ) goto select_end;
 
-#ifndef SQLITE_OMIT_EXPLAIN
-  if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
-    if( sParse.explain==2 ){
-      sqlite3VdbeSetNumCols(sParse.pVdbe, 3);
-      sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "order", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "from", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "detail", P4_STATIC);
-    }else{
-      sqlite3VdbeSetNumCols(sParse.pVdbe, 8);
-      sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "addr", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "opcode", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "p1", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 3, COLNAME_NAME, "p2", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 4, COLNAME_NAME, "p3", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 5, COLNAME_NAME, "p4", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 6, COLNAME_NAME, "p5", P4_STATIC);
-      sqlite3VdbeSetColName(sParse.pVdbe, 7, COLNAME_NAME, "comment",P4_STATIC);
+    /* If sorting index that was created by a prior OP_OpenEphemeral 
+    ** instruction ended up not being needed, then change the OP_OpenEphemeral
+    ** into an OP_Noop.
+    */
+    if( addrSortIndex>=0 && pOrderBy==0 ){
+      sqlite3VdbeChangeToNoop(v, addrSortIndex, 1);
+      p->addrOpenEphm[2] = -1;
     }
-  }
-#endif
 
-  if( sqlite3SafetyOff(db) ){
-    rc = SQLITE_MISUSE;
-  }
+    /* Use the standard inner loop
+    */
+    assert(!isDistinct);
+    selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, -1, pDest,
+                    pWInfo->iContinue, pWInfo->iBreak);
 
-  if( saveSqlFlag ){
-    sqlite3VdbeSetSql(sParse.pVdbe, zSql, sParse.zTail - zSql);
-  }
-  if( rc!=SQLITE_OK || db->mallocFailed ){
-    sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
-    assert(!(*ppStmt));
+    /* End the database scan loop.
+    */
+    sqlite3WhereEnd(pWInfo);
   }else{
-    *ppStmt = (sqlite3_stmt*)sParse.pVdbe;
-  }
+    /* This is the processing for aggregate queries */
+    NameContext sNC;    /* Name context for processing aggregate information */
+    int iAMem;          /* First Mem address for storing current GROUP BY */
+    int iBMem;          /* First Mem address for previous GROUP BY */
+    int iUseFlag;       /* Mem address holding flag indicating that at least
+                        ** one row of the input to the aggregator has been
+                        ** processed */
+    int iAbortFlag;     /* Mem address which causes query abort if positive */
+    int groupBySort;    /* Rows come from source in GROUP BY order */
+    int addrEnd;        /* End of processing for this SELECT */
 
-  if( zErrMsg ){
-    sqlite3Error(db, rc, "%s", zErrMsg);
-    sqlite3_free(zErrMsg);
-  }else{
-    sqlite3Error(db, rc, 0);
-  }
+    /* Remove any and all aliases between the result set and the
+    ** GROUP BY clause.
+    */
+    if( pGroupBy ){
+      int k;                        /* Loop counter */
+      struct ExprList_item *pItem;  /* For looping over expression in a list */
 
-  rc = sqlite3ApiExit(db, rc);
-  assert( (rc&db->errMask)==rc );
-  return rc;
-}
-static int sqlite3LockAndPrepare(
-  sqlite3 *db,              /* Database handle. */
-  const char *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  int saveSqlFlag,          /* True to copy SQL text into the sqlite3_stmt */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const char **pzTail       /* OUT: End of parsed string */
-){
-  int rc;
-  if( !sqlite3SafetyCheckOk(db) ){
-    return SQLITE_MISUSE;
-  }
-  sqlite3_mutex_enter(db->mutex);
-  sqlite3BtreeEnterAll(db);
-  rc = sqlite3Prepare(db, zSql, nBytes, saveSqlFlag, ppStmt, pzTail);
-  sqlite3BtreeLeaveAll(db);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
+      for(k=p->pEList->nExpr, pItem=p->pEList->a; k>0; k--, pItem++){
+        pItem->iAlias = 0;
+      }
+      for(k=pGroupBy->nExpr, pItem=pGroupBy->a; k>0; k--, pItem++){
+        pItem->iAlias = 0;
+      }
+    }
 
-/*
-** Rerun the compilation of a statement after a schema change.
-** Return true if the statement was recompiled successfully.
-** Return false if there is an error of some kind.
-*/
-SQLITE_PRIVATE int sqlite3Reprepare(Vdbe *p){
-  int rc;
-  sqlite3_stmt *pNew;
-  const char *zSql;
-  sqlite3 *db;
+ 
+    /* Create a label to jump to when we want to abort the query */
+    addrEnd = sqlite3VdbeMakeLabel(v);
 
-  assert( sqlite3_mutex_held(sqlite3VdbeDb(p)->mutex) );
-  zSql = sqlite3_sql((sqlite3_stmt *)p);
-  assert( zSql!=0 );  /* Reprepare only called for prepare_v2() statements */
-  db = sqlite3VdbeDb(p);
-  assert( sqlite3_mutex_held(db->mutex) );
-  rc = sqlite3LockAndPrepare(db, zSql, -1, 0, &pNew, 0);
-  if( rc ){
-    if( rc==SQLITE_NOMEM ){
-      db->mallocFailed = 1;
+    /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in
+    ** sAggInfo for all TK_AGG_FUNCTION nodes in expressions of the
+    ** SELECT statement.
+    */
+    memset(&sNC, 0, sizeof(sNC));
+    sNC.pParse = pParse;
+    sNC.pSrcList = pTabList;
+    sNC.pAggInfo = &sAggInfo;
+    sAggInfo.nSortingColumn = pGroupBy ? pGroupBy->nExpr+1 : 0;
+    sAggInfo.pGroupBy = pGroupBy;
+    sqlite3ExprAnalyzeAggList(&sNC, pEList);
+    sqlite3ExprAnalyzeAggList(&sNC, pOrderBy);
+    if( pHaving ){
+      sqlite3ExprAnalyzeAggregates(&sNC, pHaving);
     }
-    assert( pNew==0 );
-    return 0;
-  }else{
-    assert( pNew!=0 );
-  }
-  sqlite3VdbeSwap((Vdbe*)pNew, p);
-  sqlite3_transfer_bindings(pNew, (sqlite3_stmt*)p);
-  sqlite3VdbeResetStepResult((Vdbe*)pNew);
-  sqlite3VdbeFinalize((Vdbe*)pNew);
-  return 1;
-}
+    sAggInfo.nAccumulator = sAggInfo.nColumn;
+    for(i=0; i<sAggInfo.nFunc; i++){
+      assert( !ExprHasProperty(sAggInfo.aFunc[i].pExpr, EP_xIsSelect) );
+      sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->x.pList);
+    }
+    if( db->mallocFailed ) goto select_end;
 
+    /* Processing for aggregates with GROUP BY is very different and
+    ** much more complex than aggregates without a GROUP BY.
+    */
+    if( pGroupBy ){
+      KeyInfo *pKeyInfo;  /* Keying information for the group by clause */
+      int j1;             /* A-vs-B comparision jump */
+      int addrOutputRow;  /* Start of subroutine that outputs a result row */
+      int regOutputRow;   /* Return address register for output subroutine */
+      int addrSetAbort;   /* Set the abort flag and return */
+      int addrTopOfLoop;  /* Top of the input loop */
+      int addrSortingIdx; /* The OP_OpenEphemeral for the sorting index */
+      int addrReset;      /* Subroutine for resetting the accumulator */
+      int regReset;       /* Return address register for reset subroutine */
 
-/*
-** Two versions of the official API.  Legacy and new use.  In the legacy
-** version, the original SQL text is not saved in the prepared statement
-** and so if a schema change occurs, SQLITE_SCHEMA is returned by
-** sqlite3_step().  In the new version, the original SQL text is retained
-** and the statement is automatically recompiled if an schema change
-** occurs.
-*/
-SQLITE_API int sqlite3_prepare(
-  sqlite3 *db,              /* Database handle. */
-  const char *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const char **pzTail       /* OUT: End of parsed string */
-){
-  int rc;
-  rc = sqlite3LockAndPrepare(db,zSql,nBytes,0,ppStmt,pzTail);
-  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
-  return rc;
-}
-SQLITE_API int sqlite3_prepare_v2(
-  sqlite3 *db,              /* Database handle. */
-  const char *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const char **pzTail       /* OUT: End of parsed string */
-){
-  int rc;
-  rc = sqlite3LockAndPrepare(db,zSql,nBytes,1,ppStmt,pzTail);
-  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
-  return rc;
-}
+      /* If there is a GROUP BY clause we might need a sorting index to
+      ** implement it.  Allocate that sorting index now.  If it turns out
+      ** that we do not need it after all, the OpenEphemeral instruction
+      ** will be converted into a Noop.  
+      */
+      sAggInfo.sortingIdx = pParse->nTab++;
+      pKeyInfo = keyInfoFromExprList(pParse, pGroupBy);
+      addrSortingIdx = sqlite3VdbeAddOp4(v, OP_OpenEphemeral, 
+          sAggInfo.sortingIdx, sAggInfo.nSortingColumn, 
+          0, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
 
+      /* Initialize memory locations used by GROUP BY aggregate processing
+      */
+      iUseFlag = ++pParse->nMem;
+      iAbortFlag = ++pParse->nMem;
+      regOutputRow = ++pParse->nMem;
+      addrOutputRow = sqlite3VdbeMakeLabel(v);
+      regReset = ++pParse->nMem;
+      addrReset = sqlite3VdbeMakeLabel(v);
+      iAMem = pParse->nMem + 1;
+      pParse->nMem += pGroupBy->nExpr;
+      iBMem = pParse->nMem + 1;
+      pParse->nMem += pGroupBy->nExpr;
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, iAbortFlag);
+      VdbeComment((v, "clear abort flag"));
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, iUseFlag);
+      VdbeComment((v, "indicate accumulator empty"));
 
-#ifndef SQLITE_OMIT_UTF16
-/*
-** Compile the UTF-16 encoded SQL statement zSql into a statement handle.
-*/
-static int sqlite3Prepare16(
-  sqlite3 *db,              /* Database handle. */ 
-  const void *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  int saveSqlFlag,          /* True to save SQL text into the sqlite3_stmt */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const void **pzTail       /* OUT: End of parsed string */
-){
-  /* This function currently works by first transforming the UTF-16
-  ** encoded string to UTF-8, then invoking sqlite3_prepare(). The
-  ** tricky bit is figuring out the pointer to return in *pzTail.
-  */
-  char *zSql8;
-  const char *zTail8 = 0;
-  int rc = SQLITE_OK;
+      /* Begin a loop that will extract all source rows in GROUP BY order.
+      ** This might involve two separate loops with an OP_Sort in between, or
+      ** it might be a single loop that uses an index to extract information
+      ** in the right order to begin with.
+      */
+      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
+      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0);
+      if( pWInfo==0 ) goto select_end;
+      if( pGroupBy==0 ){
+        /* The optimizer is able to deliver rows in group by order so
+        ** we do not have to sort.  The OP_OpenEphemeral table will be
+        ** cancelled later because we still need to use the pKeyInfo
+        */
+        pGroupBy = p->pGroupBy;
+        groupBySort = 0;
+      }else{
+        /* Rows are coming out in undetermined order.  We have to push
+        ** each row into a sorting index, terminate the first loop,
+        ** then loop over the sorting index in order to get the output
+        ** in sorted order
+        */
+        int regBase;
+        int regRecord;
+        int nCol;
+        int nGroupBy;
 
-  if( !sqlite3SafetyCheckOk(db) ){
-    return SQLITE_MISUSE;
-  }
-  sqlite3_mutex_enter(db->mutex);
-  zSql8 = sqlite3Utf16to8(db, zSql, nBytes);
-  if( zSql8 ){
-    rc = sqlite3LockAndPrepare(db, zSql8, -1, saveSqlFlag, ppStmt, &zTail8);
-  }
+        groupBySort = 1;
+        nGroupBy = pGroupBy->nExpr;
+        nCol = nGroupBy + 1;
+        j = nGroupBy+1;
+        for(i=0; i<sAggInfo.nColumn; i++){
+          if( sAggInfo.aCol[i].iSorterColumn>=j ){
+            nCol++;
+            j++;
+          }
+        }
+        regBase = sqlite3GetTempRange(pParse, nCol);
+        sqlite3ExprCacheClear(pParse);
+        sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0);
+        sqlite3VdbeAddOp2(v, OP_Sequence, sAggInfo.sortingIdx,regBase+nGroupBy);
+        j = nGroupBy+1;
+        for(i=0; i<sAggInfo.nColumn; i++){
+          struct AggInfo_col *pCol = &sAggInfo.aCol[i];
+          if( pCol->iSorterColumn>=j ){
+            int r1 = j + regBase;
+            int r2;
 
-  if( zTail8 && pzTail ){
-    /* If sqlite3_prepare returns a tail pointer, we calculate the
-    ** equivalent pointer into the UTF-16 string by counting the unicode
-    ** characters between zSql8 and zTail8, and then returning a pointer
-    ** the same number of characters into the UTF-16 string.
-    */
-    int chars_parsed = sqlite3Utf8CharLen(zSql8, zTail8-zSql8);
-    *pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
-  }
-  sqlite3_free(zSql8); 
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
+            r2 = sqlite3ExprCodeGetColumn(pParse, 
+                               pCol->pTab, pCol->iColumn, pCol->iTable, r1, 0);
+            if( r1!=r2 ){
+              sqlite3VdbeAddOp2(v, OP_SCopy, r2, r1);
+            }
+            j++;
+          }
+        }
+        regRecord = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regRecord);
+        sqlite3VdbeAddOp2(v, OP_IdxInsert, sAggInfo.sortingIdx, regRecord);
+        sqlite3ReleaseTempReg(pParse, regRecord);
+        sqlite3ReleaseTempRange(pParse, regBase, nCol);
+        sqlite3WhereEnd(pWInfo);
+        sqlite3VdbeAddOp2(v, OP_Sort, sAggInfo.sortingIdx, addrEnd);
+        VdbeComment((v, "GROUP BY sort"));
+        sAggInfo.useSortingIdx = 1;
+        sqlite3ExprCacheClear(pParse);
+      }
+
+      /* Evaluate the current GROUP BY terms and store in b0, b1, b2...
+      ** (b0 is memory location iBMem+0, b1 is iBMem+1, and so forth)
+      ** Then compare the current GROUP BY terms against the GROUP BY terms
+      ** from the previous row currently stored in a0, a1, a2...
+      */
+      addrTopOfLoop = sqlite3VdbeCurrentAddr(v);
+      sqlite3ExprCacheClear(pParse);
+      for(j=0; j<pGroupBy->nExpr; j++){
+        if( groupBySort ){
+          sqlite3VdbeAddOp3(v, OP_Column, sAggInfo.sortingIdx, j, iBMem+j);
+        }else{
+          sAggInfo.directMode = 1;
+          sqlite3ExprCode(pParse, pGroupBy->a[j].pExpr, iBMem+j);
+        }
+      }
+      sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
+                          (char*)pKeyInfo, P4_KEYINFO);
+      j1 = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp3(v, OP_Jump, j1+1, 0, j1+1);
+
+      /* Generate code that runs whenever the GROUP BY changes.
+      ** Changes in the GROUP BY are detected by the previous code
+      ** block.  If there were no changes, this block is skipped.
+      **
+      ** This code copies current group by terms in b0,b1,b2,...
+      ** over to a0,a1,a2.  It then calls the output subroutine
+      ** and resets the aggregate accumulator registers in preparation
+      ** for the next GROUP BY batch.
+      */
+      sqlite3ExprCodeMove(pParse, iBMem, iAMem, pGroupBy->nExpr);
+      sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow);
+      VdbeComment((v, "output one row"));
+      sqlite3VdbeAddOp2(v, OP_IfPos, iAbortFlag, addrEnd);
+      VdbeComment((v, "check abort flag"));
+      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
+      VdbeComment((v, "reset accumulator"));
+
+      /* Update the aggregate accumulators based on the content of
+      ** the current row
+      */
+      sqlite3VdbeJumpHere(v, j1);
+      updateAccumulator(pParse, &sAggInfo);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iUseFlag);
+      VdbeComment((v, "indicate data in accumulator"));
 
-/*
-** Two versions of the official API.  Legacy and new use.  In the legacy
-** version, the original SQL text is not saved in the prepared statement
-** and so if a schema change occurs, SQLITE_SCHEMA is returned by
-** sqlite3_step().  In the new version, the original SQL text is retained
-** and the statement is automatically recompiled if an schema change
-** occurs.
-*/
-SQLITE_API int sqlite3_prepare16(
-  sqlite3 *db,              /* Database handle. */ 
-  const void *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const void **pzTail       /* OUT: End of parsed string */
-){
-  int rc;
-  rc = sqlite3Prepare16(db,zSql,nBytes,0,ppStmt,pzTail);
-  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
-  return rc;
-}
-SQLITE_API int sqlite3_prepare16_v2(
-  sqlite3 *db,              /* Database handle. */ 
-  const void *zSql,         /* UTF-8 encoded SQL statement. */
-  int nBytes,               /* Length of zSql in bytes. */
-  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
-  const void **pzTail       /* OUT: End of parsed string */
-){
-  int rc;
-  rc = sqlite3Prepare16(db,zSql,nBytes,1,ppStmt,pzTail);
-  assert( rc==SQLITE_OK || ppStmt==0 || *ppStmt==0 );  /* VERIFY: F13021 */
-  return rc;
-}
+      /* End of the loop
+      */
+      if( groupBySort ){
+        sqlite3VdbeAddOp2(v, OP_Next, sAggInfo.sortingIdx, addrTopOfLoop);
+      }else{
+        sqlite3WhereEnd(pWInfo);
+        sqlite3VdbeChangeToNoop(v, addrSortingIdx, 1);
+      }
 
-#endif /* SQLITE_OMIT_UTF16 */
+      /* Output the final row of result
+      */
+      sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow);
+      VdbeComment((v, "output final row"));
 
-/************** End of prepare.c *********************************************/
-/************** Begin file select.c ******************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains C code routines that are called by the parser
-** to handle SELECT statements in SQLite.
-**
-** $Id: select.c,v 1.429 2008/05/01 17:03:49 drh Exp $
-*/
+      /* Jump over the subroutines
+      */
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEnd);
 
+      /* Generate a subroutine that outputs a single row of the result
+      ** set.  This subroutine first looks at the iUseFlag.  If iUseFlag
+      ** is less than or equal to zero, the subroutine is a no-op.  If
+      ** the processing calls for the query to abort, this subroutine
+      ** increments the iAbortFlag memory location before returning in
+      ** order to signal the caller to abort.
+      */
+      addrSetAbort = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag);
+      VdbeComment((v, "set abort flag"));
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      sqlite3VdbeResolveLabel(v, addrOutputRow);
+      addrOutputRow = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2);
+      VdbeComment((v, "Groupby result generator entry point"));
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      finalizeAggFunctions(pParse, &sAggInfo);
+      sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
+      selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy,
+                      distinct, pDest,
+                      addrOutputRow+1, addrSetAbort);
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      VdbeComment((v, "end groupby result generator"));
 
-/*
-** Delete all the content of a Select structure but do not deallocate
-** the select structure itself.
-*/
-static void clearSelect(Select *p){
-  sqlite3ExprListDelete(p->pEList);
-  sqlite3SrcListDelete(p->pSrc);
-  sqlite3ExprDelete(p->pWhere);
-  sqlite3ExprListDelete(p->pGroupBy);
-  sqlite3ExprDelete(p->pHaving);
-  sqlite3ExprListDelete(p->pOrderBy);
-  sqlite3SelectDelete(p->pPrior);
-  sqlite3ExprDelete(p->pLimit);
-  sqlite3ExprDelete(p->pOffset);
-}
+      /* Generate a subroutine that will reset the group-by accumulator
+      */
+      sqlite3VdbeResolveLabel(v, addrReset);
+      resetAccumulator(pParse, &sAggInfo);
+      sqlite3VdbeAddOp1(v, OP_Return, regReset);
+     
+    } /* endif pGroupBy.  Begin aggregate queries without GROUP BY: */
+    else {
+      ExprList *pDel = 0;
+#ifndef SQLITE_OMIT_BTREECOUNT
+      Table *pTab;
+      if( (pTab = isSimpleCount(p, &sAggInfo))!=0 ){
+        /* If isSimpleCount() returns a pointer to a Table structure, then
+        ** the SQL statement is of the form:
+        **
+        **   SELECT count(*) FROM <tbl>
+        **
+        ** where the Table structure returned represents table <tbl>.
+        **
+        ** This statement is so common that it is optimized specially. The
+        ** OP_Count instruction is executed either on the intkey table that
+        ** contains the data for table <tbl> or on one of its indexes. It
+        ** is better to execute the op on an index, as indexes are almost
+        ** always spread across less pages than their corresponding tables.
+        */
+        const int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+        const int iCsr = pParse->nTab++;     /* Cursor to scan b-tree */
+        Index *pIdx;                         /* Iterator variable */
+        KeyInfo *pKeyInfo = 0;               /* Keyinfo for scanned index */
+        Index *pBest = 0;                    /* Best index found so far */
+        int iRoot = pTab->tnum;              /* Root page of scanned b-tree */
+
+        sqlite3CodeVerifySchema(pParse, iDb);
+        sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
+
+        /* Search for the index that has the least amount of columns. If
+        ** there is such an index, and it has less columns than the table
+        ** does, then we can assume that it consumes less space on disk and
+        ** will therefore be cheaper to scan to determine the query result.
+        ** In this case set iRoot to the root page number of the index b-tree
+        ** and pKeyInfo to the KeyInfo structure required to navigate the
+        ** index.
+        **
+        ** In practice the KeyInfo structure will not be used. It is only 
+        ** passed to keep OP_OpenRead happy.
+        */
+        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+          if( !pBest || pIdx->nColumn<pBest->nColumn ){
+            pBest = pIdx;
+          }
+        }
+        if( pBest && pBest->nColumn<pTab->nCol ){
+          iRoot = pBest->tnum;
+          pKeyInfo = sqlite3IndexKeyinfo(pParse, pBest);
+        }
 
-/*
-** Initialize a SelectDest structure.
-*/
-SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
-  pDest->eDest = eDest;
-  pDest->iParm = iParm;
-  pDest->affinity = 0;
-  pDest->iMem = 0;
-  pDest->nMem = 0;
-}
+        /* Open a read-only cursor, execute the OP_Count, close the cursor. */
+        sqlite3VdbeAddOp3(v, OP_OpenRead, iCsr, iRoot, iDb);
+        if( pKeyInfo ){
+          sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO_HANDOFF);
+        }
+        sqlite3VdbeAddOp2(v, OP_Count, iCsr, sAggInfo.aFunc[0].iMem);
+        sqlite3VdbeAddOp1(v, OP_Close, iCsr);
+      }else
+#endif /* SQLITE_OMIT_BTREECOUNT */
+      {
+        /* Check if the query is of one of the following forms:
+        **
+        **   SELECT min(x) FROM ...
+        **   SELECT max(x) FROM ...
+        **
+        ** If it is, then ask the code in where.c to attempt to sort results
+        ** as if there was an "ORDER ON x" or "ORDER ON x DESC" clause. 
+        ** If where.c is able to produce results sorted in this order, then
+        ** add vdbe code to break out of the processing loop after the 
+        ** first iteration (since the first iteration of the loop is 
+        ** guaranteed to operate on the row with the minimum or maximum 
+        ** value of x, the only row required).
+        **
+        ** A special flag must be passed to sqlite3WhereBegin() to slightly
+        ** modify behaviour as follows:
+        **
+        **   + If the query is a "SELECT min(x)", then the loop coded by
+        **     where.c should not iterate over any values with a NULL value
+        **     for x.
+        **
+        **   + The optimizer code in where.c (the thing that decides which
+        **     index or indices to use) should place a different priority on 
+        **     satisfying the 'ORDER BY' clause than it does in other cases.
+        **     Refer to code and comments in where.c for details.
+        */
+        ExprList *pMinMax = 0;
+        u8 flag = minMaxQuery(p);
+        if( flag ){
+          assert( !ExprHasProperty(p->pEList->a[0].pExpr, EP_xIsSelect) );
+          pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->x.pList,0);
+          pDel = pMinMax;
+          if( pMinMax && !db->mallocFailed ){
+            pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN ?1:0;
+            pMinMax->a[0].pExpr->op = TK_COLUMN;
+          }
+        }
+  
+        /* This case runs if the aggregate has no GROUP BY clause.  The
+        ** processing is much simpler since there is only a single row
+        ** of output.
+        */
+        resetAccumulator(pParse, &sAggInfo);
+        pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, flag);
+        if( pWInfo==0 ){
+          sqlite3ExprListDelete(db, pDel);
+          goto select_end;
+        }
+        updateAccumulator(pParse, &sAggInfo);
+        if( !pMinMax && flag ){
+          sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak);
+          VdbeComment((v, "%s() by index",
+                (flag==WHERE_ORDERBY_MIN?"min":"max")));
+        }
+        sqlite3WhereEnd(pWInfo);
+        finalizeAggFunctions(pParse, &sAggInfo);
+      }
 
+      pOrderBy = 0;
+      sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL);
+      selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, -1, 
+                      pDest, addrEnd, addrEnd);
+      sqlite3ExprListDelete(db, pDel);
+    }
+    sqlite3VdbeResolveLabel(v, addrEnd);
+    
+  } /* endif aggregate query */
 
-/*
-** Allocate a new Select structure and return a pointer to that
-** structure.
-*/
-SQLITE_PRIVATE Select *sqlite3SelectNew(
-  Parse *pParse,        /* Parsing context */
-  ExprList *pEList,     /* which columns to include in the result */
-  SrcList *pSrc,        /* the FROM clause -- which tables to scan */
-  Expr *pWhere,         /* the WHERE clause */
-  ExprList *pGroupBy,   /* the GROUP BY clause */
-  Expr *pHaving,        /* the HAVING clause */
-  ExprList *pOrderBy,   /* the ORDER BY clause */
-  int isDistinct,       /* true if the DISTINCT keyword is present */
-  Expr *pLimit,         /* LIMIT value.  NULL means not used */
-  Expr *pOffset         /* OFFSET value.  NULL means no offset */
-){
-  Select *pNew;
-  Select standin;
-  sqlite3 *db = pParse->db;
-  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) );
-  assert( !pOffset || pLimit );   /* Can't have OFFSET without LIMIT. */
-  if( pNew==0 ){
-    pNew = &standin;
-    memset(pNew, 0, sizeof(*pNew));
-  }
-  if( pEList==0 ){
-    pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db,TK_ALL,0,0,0), 0);
-  }
-  pNew->pEList = pEList;
-  pNew->pSrc = pSrc;
-  pNew->pWhere = pWhere;
-  pNew->pGroupBy = pGroupBy;
-  pNew->pHaving = pHaving;
-  pNew->pOrderBy = pOrderBy;
-  pNew->isDistinct = isDistinct;
-  pNew->op = TK_SELECT;
-  assert( pOffset==0 || pLimit!=0 );
-  pNew->pLimit = pLimit;
-  pNew->pOffset = pOffset;
-  pNew->iLimit = -1;
-  pNew->iOffset = -1;
-  pNew->addrOpenEphm[0] = -1;
-  pNew->addrOpenEphm[1] = -1;
-  pNew->addrOpenEphm[2] = -1;
-  if( pNew==&standin) {
-    clearSelect(pNew);
-    pNew = 0;
+  /* If there is an ORDER BY clause, then we need to sort the results
+  ** and send them to the callback one by one.
+  */
+  if( pOrderBy ){
+    generateSortTail(pParse, p, v, pEList->nExpr, pDest);
   }
-  return pNew;
-}
 
-/*
-** Delete the given Select structure and all of its substructures.
-*/
-SQLITE_PRIVATE void sqlite3SelectDelete(Select *p){
-  if( p ){
-    clearSelect(p);
-    sqlite3_free(p);
+  /* Jump here to skip this query
+  */
+  sqlite3VdbeResolveLabel(v, iEnd);
+
+  /* The SELECT was successfully coded.   Set the return code to 0
+  ** to indicate no errors.
+  */
+  rc = 0;
+
+  /* Control jumps to here if an error is encountered above, or upon
+  ** successful coding of the SELECT.
+  */
+select_end:
+
+  /* Identify column names if results of the SELECT are to be output.
+  */
+  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
+    generateColumnNames(pParse, pTabList, pEList);
   }
+
+  sqlite3DbFree(db, sAggInfo.aCol);
+  sqlite3DbFree(db, sAggInfo.aFunc);
+  return rc;
 }
 
+#if defined(SQLITE_DEBUG)
 /*
-** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
-** type of join.  Return an integer constant that expresses that type
-** in terms of the following bit values:
-**
-**     JT_INNER
-**     JT_CROSS
-**     JT_OUTER
-**     JT_NATURAL
-**     JT_LEFT
-**     JT_RIGHT
+*******************************************************************************
+** The following code is used for testing and debugging only.  The code
+** that follows does not appear in normal builds.
 **
-** A full outer join is the combination of JT_LEFT and JT_RIGHT.
+** These routines are used to print out the content of all or part of a 
+** parse structures such as Select or Expr.  Such printouts are useful
+** for helping to understand what is happening inside the code generator
+** during the execution of complex SELECT statements.
 **
-** If an illegal or unsupported join type is seen, then still return
-** a join type, but put an error in the pParse structure.
+** These routine are not called anywhere from within the normal
+** code base.  Then are intended to be called from within the debugger
+** or from temporary "printf" statements inserted for debugging.
 */
-SQLITE_PRIVATE int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){
-  int jointype = 0;
-  Token *apAll[3];
-  Token *p;
-  static const struct {
-    const char zKeyword[8];
-    u8 nChar;
-    u8 code;
-  } keywords[] = {
-    { "natural", 7, JT_NATURAL },
-    { "left",    4, JT_LEFT|JT_OUTER },
-    { "right",   5, JT_RIGHT|JT_OUTER },
-    { "full",    4, JT_LEFT|JT_RIGHT|JT_OUTER },
-    { "outer",   5, JT_OUTER },
-    { "inner",   5, JT_INNER },
-    { "cross",   5, JT_INNER|JT_CROSS },
-  };
-  int i, j;
-  apAll[0] = pA;
-  apAll[1] = pB;
-  apAll[2] = pC;
-  for(i=0; i<3 && apAll[i]; i++){
-    p = apAll[i];
-    for(j=0; j<sizeof(keywords)/sizeof(keywords[0]); j++){
-      if( p->n==keywords[j].nChar 
-          && sqlite3StrNICmp((char*)p->z, keywords[j].zKeyword, p->n)==0 ){
-        jointype |= keywords[j].code;
-        break;
-      }
-    }
-    if( j>=sizeof(keywords)/sizeof(keywords[0]) ){
-      jointype |= JT_ERROR;
-      break;
-    }
+SQLITE_PRIVATE void sqlite3PrintExpr(Expr *p){
+  if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+    sqlite3DebugPrintf("(%s", p->u.zToken);
+  }else{
+    sqlite3DebugPrintf("(%d", p->op);
   }
-  if(
-     (jointype & (JT_INNER|JT_OUTER))==(JT_INNER|JT_OUTER) ||
-     (jointype & JT_ERROR)!=0
-  ){
-    const char *zSp1 = " ";
-    const char *zSp2 = " ";
-    if( pB==0 ){ zSp1++; }
-    if( pC==0 ){ zSp2++; }
-    sqlite3ErrorMsg(pParse, "unknown or unsupported join type: "
-       "%T%s%T%s%T", pA, zSp1, pB, zSp2, pC);
-    jointype = JT_INNER;
-  }else if( jointype & JT_RIGHT ){
-    sqlite3ErrorMsg(pParse, 
-      "RIGHT and FULL OUTER JOINs are not currently supported");
-    jointype = JT_INNER;
+  if( p->pLeft ){
+    sqlite3DebugPrintf(" ");
+    sqlite3PrintExpr(p->pLeft);
   }
-  return jointype;
+  if( p->pRight ){
+    sqlite3DebugPrintf(" ");
+    sqlite3PrintExpr(p->pRight);
+  }
+  sqlite3DebugPrintf(")");
 }
-
-/*
-** Return the index of a column in a table.  Return -1 if the column
-** is not contained in the table.
-*/
-static int columnIndex(Table *pTab, const char *zCol){
+SQLITE_PRIVATE void sqlite3PrintExprList(ExprList *pList){
   int i;
-  for(i=0; i<pTab->nCol; i++){
-    if( sqlite3StrICmp(pTab->aCol[i].zName, zCol)==0 ) return i;
+  for(i=0; i<pList->nExpr; i++){
+    sqlite3PrintExpr(pList->a[i].pExpr);
+    if( i<pList->nExpr-1 ){
+      sqlite3DebugPrintf(", ");
+    }
   }
-  return -1;
-}
-
-/*
-** Set the value of a token to a '\000'-terminated string.
-*/
-static void setToken(Token *p, const char *z){
-  p->z = (u8*)z;
-  p->n = z ? strlen(z) : 0;
-  p->dyn = 0;
 }
-
-/*
-** Set the token to the double-quoted and escaped version of the string pointed
-** to by z. For example;
-**
-**    {a"bc}  ->  {"a""bc"}
-*/
-static void setQuotedToken(Parse *pParse, Token *p, const char *z){
-
-  /* Check if the string contains any " characters. If it does, then
-  ** this function will malloc space to create a quoted version of
-  ** the string in. Otherwise, save a call to sqlite3MPrintf() by
-  ** just copying the pointer to the string.
-  */
-  const char *z2 = z;
-  while( *z2 ){
-    if( *z2=='"' ) break;
-    z2++;
-  }
-
-  if( *z2 ){
-    /* String contains " characters - copy and quote the string. */
-    p->z = (u8 *)sqlite3MPrintf(pParse->db, "\"%w\"", z);
-    if( p->z ){
-      p->n = strlen((char *)p->z);
-      p->dyn = 1;
+SQLITE_PRIVATE void sqlite3PrintSelect(Select *p, int indent){
+  sqlite3DebugPrintf("%*sSELECT(%p) ", indent, "", p);
+  sqlite3PrintExprList(p->pEList);
+  sqlite3DebugPrintf("\n");
+  if( p->pSrc ){
+    char *zPrefix;
+    int i;
+    zPrefix = "FROM";
+    for(i=0; i<p->pSrc->nSrc; i++){
+      struct SrcList_item *pItem = &p->pSrc->a[i];
+      sqlite3DebugPrintf("%*s ", indent+6, zPrefix);
+      zPrefix = "";
+      if( pItem->pSelect ){
+        sqlite3DebugPrintf("(\n");
+        sqlite3PrintSelect(pItem->pSelect, indent+10);
+        sqlite3DebugPrintf("%*s)", indent+8, "");
+      }else if( pItem->zName ){
+        sqlite3DebugPrintf("%s", pItem->zName);
+      }
+      if( pItem->pTab ){
+        sqlite3DebugPrintf("(table: %s)", pItem->pTab->zName);
+      }
+      if( pItem->zAlias ){
+        sqlite3DebugPrintf(" AS %s", pItem->zAlias);
+      }
+      if( i<p->pSrc->nSrc-1 ){
+        sqlite3DebugPrintf(",");
+      }
+      sqlite3DebugPrintf("\n");
     }
-  }else{
-    /* String contains no " characters - copy the pointer. */
-    p->z = (u8*)z;
-    p->n = (z2 - z);
-    p->dyn = 0;
   }
-}
-
-/*
-** Create an expression node for an identifier with the name of zName
-*/
-SQLITE_PRIVATE Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){
-  Token dummy;
-  setToken(&dummy, zName);
-  return sqlite3PExpr(pParse, TK_ID, 0, 0, &dummy);
-}
-
-/*
-** Add a term to the WHERE expression in *ppExpr that requires the
-** zCol column to be equal in the two tables pTab1 and pTab2.
-*/
-static void addWhereTerm(
-  Parse *pParse,           /* Parsing context */
-  const char *zCol,        /* Name of the column */
-  const Table *pTab1,      /* First table */
-  const char *zAlias1,     /* Alias for first table.  May be NULL */
-  const Table *pTab2,      /* Second table */
-  const char *zAlias2,     /* Alias for second table.  May be NULL */
-  int iRightJoinTable,     /* VDBE cursor for the right table */
-  Expr **ppExpr,           /* Add the equality term to this expression */
-  int isOuterJoin          /* True if dealing with an OUTER join */
-){
-  Expr *pE1a, *pE1b, *pE1c;
-  Expr *pE2a, *pE2b, *pE2c;
-  Expr *pE;
-
-  pE1a = sqlite3CreateIdExpr(pParse, zCol);
-  pE2a = sqlite3CreateIdExpr(pParse, zCol);
-  if( zAlias1==0 ){
-    zAlias1 = pTab1->zName;
+  if( p->pWhere ){
+    sqlite3DebugPrintf("%*s WHERE ", indent, "");
+    sqlite3PrintExpr(p->pWhere);
+    sqlite3DebugPrintf("\n");
   }
-  pE1b = sqlite3CreateIdExpr(pParse, zAlias1);
-  if( zAlias2==0 ){
-    zAlias2 = pTab2->zName;
+  if( p->pGroupBy ){
+    sqlite3DebugPrintf("%*s GROUP BY ", indent, "");
+    sqlite3PrintExprList(p->pGroupBy);
+    sqlite3DebugPrintf("\n");
   }
-  pE2b = sqlite3CreateIdExpr(pParse, zAlias2);
-  pE1c = sqlite3PExpr(pParse, TK_DOT, pE1b, pE1a, 0);
-  pE2c = sqlite3PExpr(pParse, TK_DOT, pE2b, pE2a, 0);
-  pE = sqlite3PExpr(pParse, TK_EQ, pE1c, pE2c, 0);
-  if( pE && isOuterJoin ){
-    ExprSetProperty(pE, EP_FromJoin);
-    pE->iRightJoinTable = iRightJoinTable;
+  if( p->pHaving ){
+    sqlite3DebugPrintf("%*s HAVING ", indent, "");
+    sqlite3PrintExpr(p->pHaving);
+    sqlite3DebugPrintf("\n");
+  }
+  if( p->pOrderBy ){
+    sqlite3DebugPrintf("%*s ORDER BY ", indent, "");
+    sqlite3PrintExprList(p->pOrderBy);
+    sqlite3DebugPrintf("\n");
   }
-  *ppExpr = sqlite3ExprAnd(pParse->db,*ppExpr, pE);
 }
+/* End of the structure debug printing code
+*****************************************************************************/
+#endif /* defined(SQLITE_TEST) || defined(SQLITE_DEBUG) */
 
+/************** End of select.c **********************************************/
+/************** Begin file table.c *******************************************/
 /*
-** Set the EP_FromJoin property on all terms of the given expression.
-** And set the Expr.iRightJoinTable to iTable for every term in the
-** expression.
-**
-** The EP_FromJoin property is used on terms of an expression to tell
-** the LEFT OUTER JOIN processing logic that this term is part of the
-** join restriction specified in the ON or USING clause and not a part
-** of the more general WHERE clause.  These terms are moved over to the
-** WHERE clause during join processing but we need to remember that they
-** originated in the ON or USING clause.
+** 2001 September 15
 **
-** The Expr.iRightJoinTable tells the WHERE clause processing that the
-** expression depends on table iRightJoinTable even if that table is not
-** explicitly mentioned in the expression.  That information is needed
-** for cases like this:
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-**    SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.b AND t1.x=5
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** The where clause needs to defer the handling of the t1.x=5
-** term until after the t2 loop of the join.  In that way, a
-** NULL t2 row will be inserted whenever t1.x!=5.  If we do not
-** defer the handling of t1.x=5, it will be processed immediately
-** after the t1 loop and rows with t1.x!=5 will never appear in
-** the output, which is incorrect.
-*/
-static void setJoinExpr(Expr *p, int iTable){
-  while( p ){
-    ExprSetProperty(p, EP_FromJoin);
-    p->iRightJoinTable = iTable;
-    setJoinExpr(p->pLeft, iTable);
-    p = p->pRight;
-  } 
-}
-
-/*
-** This routine processes the join information for a SELECT statement.
-** ON and USING clauses are converted into extra terms of the WHERE clause.
-** NATURAL joins also create extra WHERE clause terms.
+*************************************************************************
+** This file contains the sqlite3_get_table() and sqlite3_free_table()
+** interface routines.  These are just wrappers around the main
+** interface routine of sqlite3_exec().
 **
-** The terms of a FROM clause are contained in the Select.pSrc structure.
-** The left most table is the first entry in Select.pSrc.  The right-most
-** table is the last entry.  The join operator is held in the entry to
-** the left.  Thus entry 0 contains the join operator for the join between
-** entries 0 and 1.  Any ON or USING clauses associated with the join are
-** also attached to the left entry.
+** These routines are in a separate files so that they will not be linked
+** if they are not used.
 **
-** This routine returns the number of errors encountered.
+** $Id: table.c,v 1.40 2009/04/10 14:28:00 drh Exp $
 */
-static int sqliteProcessJoin(Parse *pParse, Select *p){
-  SrcList *pSrc;                  /* All tables in the FROM clause */
-  int i, j;                       /* Loop counters */
-  struct SrcList_item *pLeft;     /* Left table being joined */
-  struct SrcList_item *pRight;    /* Right table being joined */
-
-  pSrc = p->pSrc;
-  pLeft = &pSrc->a[0];
-  pRight = &pLeft[1];
-  for(i=0; i<pSrc->nSrc-1; i++, pRight++, pLeft++){
-    Table *pLeftTab = pLeft->pTab;
-    Table *pRightTab = pRight->pTab;
-    int isOuter;
 
-    if( pLeftTab==0 || pRightTab==0 ) continue;
-    isOuter = (pRight->jointype & JT_OUTER)!=0;
+#ifndef SQLITE_OMIT_GET_TABLE
 
-    /* When the NATURAL keyword is present, add WHERE clause terms for
-    ** every column that the two tables have in common.
-    */
-    if( pRight->jointype & JT_NATURAL ){
-      if( pRight->pOn || pRight->pUsing ){
-        sqlite3ErrorMsg(pParse, "a NATURAL join may not have "
-           "an ON or USING clause", 0);
-        return 1;
-      }
-      for(j=0; j<pLeftTab->nCol; j++){
-        char *zName = pLeftTab->aCol[j].zName;
-        if( columnIndex(pRightTab, zName)>=0 ){
-          addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
-                              pRightTab, pRight->zAlias,
-                              pRight->iCursor, &p->pWhere, isOuter);
-          
-        }
-      }
-    }
+/*
+** This structure is used to pass data from sqlite3_get_table() through
+** to the callback function is uses to build the result.
+*/
+typedef struct TabResult {
+  char **azResult;   /* Accumulated output */
+  char *zErrMsg;     /* Error message text, if an error occurs */
+  int nAlloc;        /* Slots allocated for azResult[] */
+  int nRow;          /* Number of rows in the result */
+  int nColumn;       /* Number of columns in the result */
+  int nData;         /* Slots used in azResult[].  (nRow+1)*nColumn */
+  int rc;            /* Return code from sqlite3_exec() */
+} TabResult;
 
-    /* Disallow both ON and USING clauses in the same join
-    */
-    if( pRight->pOn && pRight->pUsing ){
-      sqlite3ErrorMsg(pParse, "cannot have both ON and USING "
-        "clauses in the same join");
-      return 1;
-    }
+/*
+** This routine is called once for each row in the result table.  Its job
+** is to fill in the TabResult structure appropriately, allocating new
+** memory as necessary.
+*/
+static int sqlite3_get_table_cb(void *pArg, int nCol, char **argv, char **colv){
+  TabResult *p = (TabResult*)pArg;  /* Result accumulator */
+  int need;                         /* Slots needed in p->azResult[] */
+  int i;                            /* Loop counter */
+  char *z;                          /* A single column of result */
 
-    /* Add the ON clause to the end of the WHERE clause, connected by
-    ** an AND operator.
-    */
-    if( pRight->pOn ){
-      if( isOuter ) setJoinExpr(pRight->pOn, pRight->iCursor);
-      p->pWhere = sqlite3ExprAnd(pParse->db, p->pWhere, pRight->pOn);
-      pRight->pOn = 0;
+  /* Make sure there is enough space in p->azResult to hold everything
+  ** we need to remember from this invocation of the callback.
+  */
+  if( p->nRow==0 && argv!=0 ){
+    need = nCol*2;
+  }else{
+    need = nCol;
+  }
+  if( p->nData + need > p->nAlloc ){
+    char **azNew;
+    p->nAlloc = p->nAlloc*2 + need;
+    azNew = sqlite3_realloc( p->azResult, sizeof(char*)*p->nAlloc );
+    if( azNew==0 ) goto malloc_failed;
+    p->azResult = azNew;
+  }
+
+  /* If this is the first row, then generate an extra row containing
+  ** the names of all columns.
+  */
+  if( p->nRow==0 ){
+    p->nColumn = nCol;
+    for(i=0; i<nCol; i++){
+      z = sqlite3_mprintf("%s", colv[i]);
+      if( z==0 ) goto malloc_failed;
+      p->azResult[p->nData++] = z;
     }
+  }else if( p->nColumn!=nCol ){
+    sqlite3_free(p->zErrMsg);
+    p->zErrMsg = sqlite3_mprintf(
+       "sqlite3_get_table() called with two or more incompatible queries"
+    );
+    p->rc = SQLITE_ERROR;
+    return 1;
+  }
 
-    /* Create extra terms on the WHERE clause for each column named
-    ** in the USING clause.  Example: If the two tables to be joined are 
-    ** A and B and the USING clause names X, Y, and Z, then add this
-    ** to the WHERE clause:    A.X=B.X AND A.Y=B.Y AND A.Z=B.Z
-    ** Report an error if any column mentioned in the USING clause is
-    ** not contained in both tables to be joined.
-    */
-    if( pRight->pUsing ){
-      IdList *pList = pRight->pUsing;
-      for(j=0; j<pList->nId; j++){
-        char *zName = pList->a[j].zName;
-        if( columnIndex(pLeftTab, zName)<0 || columnIndex(pRightTab, zName)<0 ){
-          sqlite3ErrorMsg(pParse, "cannot join using column %s - column "
-            "not present in both tables", zName);
-          return 1;
-        }
-        addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
-                            pRightTab, pRight->zAlias,
-                            pRight->iCursor, &p->pWhere, isOuter);
+  /* Copy over the row data
+  */
+  if( argv!=0 ){
+    for(i=0; i<nCol; i++){
+      if( argv[i]==0 ){
+        z = 0;
+      }else{
+        int n = sqlite3Strlen30(argv[i])+1;
+        z = sqlite3_malloc( n );
+        if( z==0 ) goto malloc_failed;
+        memcpy(z, argv[i], n);
       }
+      p->azResult[p->nData++] = z;
     }
+    p->nRow++;
   }
   return 0;
+
+malloc_failed:
+  p->rc = SQLITE_NOMEM;
+  return 1;
 }
 
 /*
-** Insert code into "v" that will push the record on the top of the
-** stack into the sorter.
+** Query the database.  But instead of invoking a callback for each row,
+** malloc() for space to hold the result and return the entire results
+** at the conclusion of the call.
+**
+** The result that is written to ***pazResult is held in memory obtained
+** from malloc().  But the caller cannot free this memory directly.  
+** Instead, the entire table should be passed to sqlite3_free_table() when
+** the calling procedure is finished using it.
 */
-static void pushOntoSorter(
-  Parse *pParse,         /* Parser context */
-  ExprList *pOrderBy,    /* The ORDER BY clause */
-  Select *pSelect,       /* The whole SELECT statement */
-  int regData            /* Register holding data to be sorted */
+SQLITE_API int sqlite3_get_table(
+  sqlite3 *db,                /* The database on which the SQL executes */
+  const char *zSql,           /* The SQL to be executed */
+  char ***pazResult,          /* Write the result table here */
+  int *pnRow,                 /* Write the number of rows in the result here */
+  int *pnColumn,              /* Write the number of columns of result here */
+  char **pzErrMsg             /* Write error messages here */
 ){
-  Vdbe *v = pParse->pVdbe;
-  int nExpr = pOrderBy->nExpr;
-  int regBase = sqlite3GetTempRange(pParse, nExpr+2);
-  int regRecord = sqlite3GetTempReg(pParse);
-  sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0);
-  sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr);
-  sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1);
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nExpr + 2, regRecord);
-  sqlite3VdbeAddOp2(v, OP_IdxInsert, pOrderBy->iECursor, regRecord);
-  sqlite3ReleaseTempReg(pParse, regRecord);
-  sqlite3ReleaseTempRange(pParse, regBase, nExpr+2);
-  if( pSelect->iLimit>=0 ){
-    int addr1, addr2;
-    int iLimit;
-    if( pSelect->pOffset ){
-      iLimit = pSelect->iOffset+1;
-    }else{
-      iLimit = pSelect->iLimit;
+  int rc;
+  TabResult res;
+
+  *pazResult = 0;
+  if( pnColumn ) *pnColumn = 0;
+  if( pnRow ) *pnRow = 0;
+  if( pzErrMsg ) *pzErrMsg = 0;
+  res.zErrMsg = 0;
+  res.nRow = 0;
+  res.nColumn = 0;
+  res.nData = 1;
+  res.nAlloc = 20;
+  res.rc = SQLITE_OK;
+  res.azResult = sqlite3_malloc(sizeof(char*)*res.nAlloc );
+  if( res.azResult==0 ){
+     db->errCode = SQLITE_NOMEM;
+     return SQLITE_NOMEM;
+  }
+  res.azResult[0] = 0;
+  rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
+  assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
+  res.azResult[0] = SQLITE_INT_TO_PTR(res.nData);
+  if( (rc&0xff)==SQLITE_ABORT ){
+    sqlite3_free_table(&res.azResult[1]);
+    if( res.zErrMsg ){
+      if( pzErrMsg ){
+        sqlite3_free(*pzErrMsg);
+        *pzErrMsg = sqlite3_mprintf("%s",res.zErrMsg);
+      }
+      sqlite3_free(res.zErrMsg);
     }
-    addr1 = sqlite3VdbeAddOp1(v, OP_IfZero, iLimit);
-    sqlite3VdbeAddOp2(v, OP_AddImm, iLimit, -1);
-    addr2 = sqlite3VdbeAddOp0(v, OP_Goto);
-    sqlite3VdbeJumpHere(v, addr1);
-    sqlite3VdbeAddOp1(v, OP_Last, pOrderBy->iECursor);
-    sqlite3VdbeAddOp1(v, OP_Delete, pOrderBy->iECursor);
-    sqlite3VdbeJumpHere(v, addr2);
-    pSelect->iLimit = -1;
+    db->errCode = res.rc;  /* Assume 32-bit assignment is atomic */
+    return res.rc;
+  }
+  sqlite3_free(res.zErrMsg);
+  if( rc!=SQLITE_OK ){
+    sqlite3_free_table(&res.azResult[1]);
+    return rc;
+  }
+  if( res.nAlloc>res.nData ){
+    char **azNew;
+    azNew = sqlite3_realloc( res.azResult, sizeof(char*)*res.nData );
+    if( azNew==0 ){
+      sqlite3_free_table(&res.azResult[1]);
+      db->errCode = SQLITE_NOMEM;
+      return SQLITE_NOMEM;
+    }
+    res.azResult = azNew;
   }
+  *pazResult = &res.azResult[1];
+  if( pnColumn ) *pnColumn = res.nColumn;
+  if( pnRow ) *pnRow = res.nRow;
+  return rc;
 }
 
 /*
-** Add code to implement the OFFSET
+** This routine frees the space the sqlite3_get_table() malloced.
 */
-static void codeOffset(
-  Vdbe *v,          /* Generate code into this VM */
-  Select *p,        /* The SELECT statement being coded */
-  int iContinue     /* Jump here to skip the current record */
+SQLITE_API void sqlite3_free_table(
+  char **azResult            /* Result returned from from sqlite3_get_table() */
 ){
-  if( p->iOffset>=0 && iContinue!=0 ){
-    int addr;
-    sqlite3VdbeAddOp2(v, OP_AddImm, p->iOffset, -1);
-    addr = sqlite3VdbeAddOp1(v, OP_IfNeg, p->iOffset);
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iContinue);
-    VdbeComment((v, "skip OFFSET records"));
-    sqlite3VdbeJumpHere(v, addr);
+  if( azResult ){
+    int i, n;
+    azResult--;
+    assert( azResult!=0 );
+    n = SQLITE_PTR_TO_INT(azResult[0]);
+    for(i=1; i<n; i++){ if( azResult[i] ) sqlite3_free(azResult[i]); }
+    sqlite3_free(azResult);
   }
 }
 
+#endif /* SQLITE_OMIT_GET_TABLE */
+
+/************** End of table.c ***********************************************/
+/************** Begin file trigger.c *****************************************/
 /*
-** Add code that will check to make sure the N registers starting at iMem
-** form a distinct entry.  iTab is a sorting index that holds previously
-** seen combinations of the N values.  A new entry is made in iTab
-** if the current N values are new.
 **
-** A jump to addrRepeat is made and the N+1 values are popped from the
-** stack if the top N elements are not distinct.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+**
+** $Id: trigger.c,v 1.143 2009/08/10 03:57:58 shane Exp $
 */
-static void codeDistinct(
-  Parse *pParse,     /* Parsing and code generating context */
-  int iTab,          /* A sorting index used to test for distinctness */
-  int addrRepeat,    /* Jump to here if not distinct */
-  int N,             /* Number of elements */
-  int iMem           /* First element */
-){
-  Vdbe *v;
-  int r1;
 
-  v = pParse->pVdbe;
-  r1 = sqlite3GetTempReg(pParse);
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, iMem, N, r1);
-  sqlite3VdbeAddOp3(v, OP_Found, iTab, addrRepeat, r1);
-  sqlite3VdbeAddOp2(v, OP_IdxInsert, iTab, r1);
-  sqlite3ReleaseTempReg(pParse, r1);
+#ifndef SQLITE_OMIT_TRIGGER
+/*
+** Delete a linked list of TriggerStep structures.
+*/
+SQLITE_PRIVATE void sqlite3DeleteTriggerStep(sqlite3 *db, TriggerStep *pTriggerStep){
+  while( pTriggerStep ){
+    TriggerStep * pTmp = pTriggerStep;
+    pTriggerStep = pTriggerStep->pNext;
+
+    sqlite3ExprDelete(db, pTmp->pWhere);
+    sqlite3ExprListDelete(db, pTmp->pExprList);
+    sqlite3SelectDelete(db, pTmp->pSelect);
+    sqlite3IdListDelete(db, pTmp->pIdList);
+
+    sqlite3DbFree(db, pTmp);
+  }
 }
 
 /*
-** Generate an error message when a SELECT is used within a subexpression
-** (example:  "a IN (SELECT * FROM table)") but it has more than 1 result
-** column.  We do this in a subroutine because the error occurs in multiple
-** places.
+** Given table pTab, return a list of all the triggers attached to 
+** the table. The list is connected by Trigger.pNext pointers.
+**
+** All of the triggers on pTab that are in the same database as pTab
+** are already attached to pTab->pTrigger.  But there might be additional
+** triggers on pTab in the TEMP schema.  This routine prepends all
+** TEMP triggers on pTab to the beginning of the pTab->pTrigger list
+** and returns the combined list.
+**
+** To state it another way:  This routine returns a list of all triggers
+** that fire off of pTab.  The list will include any TEMP triggers on
+** pTab as well as the triggers lised in pTab->pTrigger.
 */
-static int checkForMultiColumnSelectError(
-  Parse *pParse,       /* Parse context. */
-  SelectDest *pDest,   /* Destination of SELECT results */
-  int nExpr            /* Number of result columns returned by SELECT */
-){
-  int eDest = pDest->eDest;
-  if( nExpr>1 && (eDest==SRT_Mem || eDest==SRT_Set) ){
-    sqlite3ErrorMsg(pParse, "only a single result allowed for "
-       "a SELECT that is part of an expression");
-    return 1;
-  }else{
+SQLITE_PRIVATE Trigger *sqlite3TriggerList(Parse *pParse, Table *pTab){
+  Schema * const pTmpSchema = pParse->db->aDb[1].pSchema;
+  Trigger *pList = 0;                  /* List of triggers to return */
+
+  if( pParse->disableTriggers ){
     return 0;
   }
+
+  if( pTmpSchema!=pTab->pSchema ){
+    HashElem *p;
+    for(p=sqliteHashFirst(&pTmpSchema->trigHash); p; p=sqliteHashNext(p)){
+      Trigger *pTrig = (Trigger *)sqliteHashData(p);
+      if( pTrig->pTabSchema==pTab->pSchema
+       && 0==sqlite3StrICmp(pTrig->table, pTab->zName) 
+      ){
+        pTrig->pNext = (pList ? pList : pTab->pTrigger);
+        pList = pTrig;
+      }
+    }
+  }
+
+  return (pList ? pList : pTab->pTrigger);
 }
 
 /*
-** This routine generates the code for the inside of the inner loop
-** of a SELECT.
-**
-** If srcTab and nColumn are both zero, then the pEList expressions
-** are evaluated in order to get the data for this row.  If nColumn>0
-** then data is pulled from srcTab and pEList is used only to get the
-** datatypes for each column.
+** This is called by the parser when it sees a CREATE TRIGGER statement
+** up to the point of the BEGIN before the trigger actions.  A Trigger
+** structure is generated based on the information available and stored
+** in pParse->pNewTrigger.  After the trigger actions have been parsed, the
+** sqlite3FinishTrigger() function is called to complete the trigger
+** construction process.
 */
-static void selectInnerLoop(
-  Parse *pParse,          /* The parser context */
-  Select *p,              /* The complete select statement being coded */
-  ExprList *pEList,       /* List of values being extracted */
-  int srcTab,             /* Pull data from this table */
-  int nColumn,            /* Number of columns in the source table */
-  ExprList *pOrderBy,     /* If not NULL, sort results using this key */
-  int distinct,           /* If >=0, make sure results are distinct */
-  SelectDest *pDest,      /* How to dispose of the results */
-  int iContinue,          /* Jump here to continue with next row */
-  int iBreak,             /* Jump here to break out of the inner loop */
-  char *aff               /* affinity string if eDest is SRT_Union */
+SQLITE_PRIVATE void sqlite3BeginTrigger(
+  Parse *pParse,      /* The parse context of the CREATE TRIGGER statement */
+  Token *pName1,      /* The name of the trigger */
+  Token *pName2,      /* The name of the trigger */
+  int tr_tm,          /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
+  int op,             /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
+  IdList *pColumns,   /* column list if this is an UPDATE OF trigger */
+  SrcList *pTableName,/* The name of the table/view the trigger applies to */
+  Expr *pWhen,        /* WHEN clause */
+  int isTemp,         /* True if the TEMPORARY keyword is present */
+  int noErr           /* Suppress errors if the trigger already exists */
 ){
-  Vdbe *v = pParse->pVdbe;
-  int i;
-  int hasDistinct;        /* True if the DISTINCT keyword is present */
-  int regResult;              /* Start of memory holding result set */
-  int eDest = pDest->eDest;   /* How to dispose of results */
-  int iParm = pDest->iParm;   /* First argument to disposal method */
-  int nResultCol;             /* Number of result columns */
-
-  if( v==0 ) return;
-  assert( pEList!=0 );
+  Trigger *pTrigger = 0;  /* The new trigger */
+  Table *pTab;            /* Table that the trigger fires off of */
+  char *zName = 0;        /* Name of the trigger */
+  sqlite3 *db = pParse->db;  /* The database connection */
+  int iDb;                /* The database to store the trigger in */
+  Token *pName;           /* The unqualified db name */
+  DbFixer sFix;           /* State vector for the DB fixer */
+  int iTabDb;             /* Index of the database holding pTab */
 
-  /* If there was a LIMIT clause on the SELECT statement, then do the check
-  ** to see if this row should be output.
-  */
-  hasDistinct = distinct>=0 && pEList->nExpr>0;
-  if( pOrderBy==0 && !hasDistinct ){
-    codeOffset(v, p, iContinue);
+  assert( pName1!=0 );   /* pName1->z might be NULL, but not pName1 itself */
+  assert( pName2!=0 );
+  assert( op==TK_INSERT || op==TK_UPDATE || op==TK_DELETE );
+  assert( op>0 && op<0xff );
+  if( isTemp ){
+    /* If TEMP was specified, then the trigger name may not be qualified. */
+    if( pName2->n>0 ){
+      sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
+      goto trigger_cleanup;
+    }
+    iDb = 1;
+    pName = pName1;
+  }else{
+    /* Figure out the db that the the trigger will be created in */
+    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
+    if( iDb<0 ){
+      goto trigger_cleanup;
+    }
   }
 
-  /* Pull the requested columns.
+  /* If the trigger name was unqualified, and the table is a temp table,
+  ** then set iDb to 1 to create the trigger in the temporary database.
+  ** If sqlite3SrcListLookup() returns 0, indicating the table does not
+  ** exist, the error is caught by the block below.
   */
-  if( nColumn>0 ){
-    nResultCol = nColumn;
-  }else{
-    nResultCol = pEList->nExpr;
+  if( !pTableName || db->mallocFailed ){
+    goto trigger_cleanup;
   }
-  if( pDest->iMem==0 ){
-    pDest->iMem = sqlite3GetTempRange(pParse, nResultCol);
-    pDest->nMem = nResultCol;
-  }else if( pDest->nMem!=nResultCol ){
-    /* This happens when two SELECTs of a compound SELECT have differing
-    ** numbers of result columns.  The error message will be generated by
-    ** a higher-level routine. */
-    return;
+  pTab = sqlite3SrcListLookup(pParse, pTableName);
+  if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
+    iDb = 1;
   }
-  regResult = pDest->iMem;
-  if( nColumn>0 ){
-    for(i=0; i<nColumn; i++){
-      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
+
+  /* Ensure the table name matches database name and that the table exists */
+  if( db->mallocFailed ) goto trigger_cleanup;
+  assert( pTableName->nSrc==1 );
+  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) && 
+      sqlite3FixSrcList(&sFix, pTableName) ){
+    goto trigger_cleanup;
+  }
+  pTab = sqlite3SrcListLookup(pParse, pTableName);
+  if( !pTab ){
+    /* The table does not exist. */
+    if( db->init.iDb==1 ){
+      /* Ticket #3810.
+      ** Normally, whenever a table is dropped, all associated triggers are
+      ** dropped too.  But if a TEMP trigger is created on a non-TEMP table
+      ** and the table is dropped by a different database connection, the
+      ** trigger is not visible to the database connection that does the
+      ** drop so the trigger cannot be dropped.  This results in an
+      ** "orphaned trigger" - a trigger whose associated table is missing.
+      */
+      db->init.orphanTrigger = 1;
     }
-  }else if( eDest!=SRT_Exists ){
-    /* If the destination is an EXISTS(...) expression, the actual
-    ** values returned by the SELECT are not required.
-    */
-    sqlite3ExprCodeExprList(pParse, pEList, regResult, eDest==SRT_Callback);
+    goto trigger_cleanup;
+  }
+  if( IsVirtual(pTab) ){
+    sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
+    goto trigger_cleanup;
   }
-  nColumn = nResultCol;
 
-  /* If the DISTINCT keyword was present on the SELECT statement
-  ** and this row has been seen before, then do not make this row
-  ** part of the result.
-  */
-  if( hasDistinct ){
-    assert( pEList!=0 );
-    assert( pEList->nExpr==nColumn );
-    codeDistinct(pParse, distinct, iContinue, nColumn, regResult);
-    if( pOrderBy==0 ){
-      codeOffset(v, p, iContinue);
+  /* Check that the trigger name is not reserved and that no trigger of the
+  ** specified name exists */
+  zName = sqlite3NameFromToken(db, pName);
+  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
+    goto trigger_cleanup;
+  }
+  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),
+                      zName, sqlite3Strlen30(zName)) ){
+    if( !noErr ){
+      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
     }
+    goto trigger_cleanup;
   }
 
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    return;
+  /* Do not create a trigger on a system table */
+  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
+    sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
+    pParse->nErr++;
+    goto trigger_cleanup;
   }
 
-  switch( eDest ){
-    /* In this mode, write each query result to the key of the temporary
-    ** table iParm.
-    */
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
-    case SRT_Union: {
-      int r1;
-      r1 = sqlite3GetTempReg(pParse);
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
-      if( aff ){
-        sqlite3VdbeChangeP4(v, -1, aff, P4_STATIC);
-      }
-      sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
-      sqlite3ReleaseTempReg(pParse, r1);
-      break;
-    }
+  /* INSTEAD of triggers are only for views and views only support INSTEAD
+  ** of triggers.
+  */
+  if( pTab->pSelect && tr_tm!=TK_INSTEAD ){
+    sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S", 
+        (tr_tm == TK_BEFORE)?"BEFORE":"AFTER", pTableName, 0);
+    goto trigger_cleanup;
+  }
+  if( !pTab->pSelect && tr_tm==TK_INSTEAD ){
+    sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
+        " trigger on table: %S", pTableName, 0);
+    goto trigger_cleanup;
+  }
+  iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
 
-    /* Construct a record from the query result, but instead of
-    ** saving that record, use it as a key to delete elements from
-    ** the temporary table iParm.
-    */
-    case SRT_Except: {
-      sqlite3VdbeAddOp3(v, OP_IdxDelete, iParm, regResult, nColumn);
-      break;
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  {
+    int code = SQLITE_CREATE_TRIGGER;
+    const char *zDb = db->aDb[iTabDb].zName;
+    const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
+    if( iTabDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
+    if( sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig) ){
+      goto trigger_cleanup;
+    }
+    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb),0,zDb)){
+      goto trigger_cleanup;
     }
+  }
 #endif
 
-    /* Store the result as data using a unique key.
-    */
-    case SRT_Table:
-    case SRT_EphemTab: {
-      int r1 = sqlite3GetTempReg(pParse);
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
-      if( pOrderBy ){
-        pushOntoSorter(pParse, pOrderBy, p, r1);
-      }else{
-        int r2 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, r2);
-        sqlite3VdbeAddOp3(v, OP_Insert, iParm, r1, r2);
-        sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
-        sqlite3ReleaseTempReg(pParse, r2);
-      }
-      sqlite3ReleaseTempReg(pParse, r1);
-      break;
-    }
+  /* INSTEAD OF triggers can only appear on views and BEFORE triggers
+  ** cannot appear on views.  So we might as well translate every
+  ** INSTEAD OF trigger into a BEFORE trigger.  It simplifies code
+  ** elsewhere.
+  */
+  if (tr_tm == TK_INSTEAD){
+    tr_tm = TK_BEFORE;
+  }
 
-#ifndef SQLITE_OMIT_SUBQUERY
-    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
-    ** then there should be a single item on the stack.  Write this
-    ** item into the set table with bogus data.
-    */
-    case SRT_Set: {
-      int addr2;
+  /* Build the Trigger object */
+  pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
+  if( pTrigger==0 ) goto trigger_cleanup;
+  pTrigger->zName = zName;
+  zName = 0;
+  pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
+  pTrigger->pSchema = db->aDb[iDb].pSchema;
+  pTrigger->pTabSchema = pTab->pSchema;
+  pTrigger->op = (u8)op;
+  pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
+  pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
+  pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
+  assert( pParse->pNewTrigger==0 );
+  pParse->pNewTrigger = pTrigger;
 
-      assert( nColumn==1 );
-      addr2 = sqlite3VdbeAddOp1(v, OP_IsNull, regResult);
-      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
-      if( pOrderBy ){
-        /* At first glance you would think we could optimize out the
-        ** ORDER BY in this case since the order of entries in the set
-        ** does not matter.  But there might be a LIMIT clause, in which
-        ** case the order does matter */
-        pushOntoSorter(pParse, pOrderBy, p, regResult);
-      }else{
-        int r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, 1, r1, &p->affinity, 1);
-        sqlite3ExprCacheAffinityChange(pParse, regResult, 1);
-        sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
-        sqlite3ReleaseTempReg(pParse, r1);
-      }
-      sqlite3VdbeJumpHere(v, addr2);
-      break;
-    }
+trigger_cleanup:
+  sqlite3DbFree(db, zName);
+  sqlite3SrcListDelete(db, pTableName);
+  sqlite3IdListDelete(db, pColumns);
+  sqlite3ExprDelete(db, pWhen);
+  if( !pParse->pNewTrigger ){
+    sqlite3DeleteTrigger(db, pTrigger);
+  }else{
+    assert( pParse->pNewTrigger==pTrigger );
+  }
+}
 
-    /* If any row exist in the result set, record that fact and abort.
-    */
-    case SRT_Exists: {
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iParm);
-      /* The LIMIT clause will terminate the loop for us */
-      break;
-    }
+/*
+** This routine is called after all of the trigger actions have been parsed
+** in order to complete the process of building the trigger.
+*/
+SQLITE_PRIVATE void sqlite3FinishTrigger(
+  Parse *pParse,          /* Parser context */
+  TriggerStep *pStepList, /* The triggered program */
+  Token *pAll             /* Token that describes the complete CREATE TRIGGER */
+){
+  Trigger *pTrig = pParse->pNewTrigger;    /* Trigger being finished */
+  char *zName;                             /* Name of trigger */
+  sqlite3 *db = pParse->db;                /* The database */
+  DbFixer sFix;
+  int iDb;                                 /* Database containing the trigger */
+  Token nameToken;           /* Trigger name for error reporting */
+
+  pTrig = pParse->pNewTrigger;
+  pParse->pNewTrigger = 0;
+  if( NEVER(pParse->nErr) || !pTrig ) goto triggerfinish_cleanup;
+  zName = pTrig->zName;
+  iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
+  pTrig->step_list = pStepList;
+  while( pStepList ){
+    pStepList->pTrig = pTrig;
+    pStepList = pStepList->pNext;
+  }
+  nameToken.z = pTrig->zName;
+  nameToken.n = sqlite3Strlen30(nameToken.z);
+  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &nameToken) 
+          && sqlite3FixTriggerStep(&sFix, pTrig->step_list) ){
+    goto triggerfinish_cleanup;
+  }
 
-    /* If this is a scalar select that is part of an expression, then
-    ** store the results in the appropriate memory cell and break out
-    ** of the scan loop.
-    */
-    case SRT_Mem: {
-      assert( nColumn==1 );
-      if( pOrderBy ){
-        pushOntoSorter(pParse, pOrderBy, p, regResult);
-      }else{
-        sqlite3ExprCodeMove(pParse, regResult, iParm);
-        /* The LIMIT clause will jump out of the loop for us */
-      }
-      break;
-    }
-#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
+  /* if we are not initializing, and this trigger is not on a TEMP table, 
+  ** build the sqlite_master entry
+  */
+  if( !db->init.busy ){
+    Vdbe *v;
+    char *z;
 
-    /* Send the data to the callback function or to a subroutine.  In the
-    ** case of a subroutine, the subroutine itself is responsible for
-    ** popping the data from the stack.
-    */
-    case SRT_Subroutine:
-    case SRT_Callback: {
-      if( pOrderBy ){
-        int r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
-        pushOntoSorter(pParse, pOrderBy, p, r1);
-        sqlite3ReleaseTempReg(pParse, r1);
-      }else if( eDest==SRT_Subroutine ){
-        sqlite3VdbeAddOp2(v, OP_Gosub, 0, iParm);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
-        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
-      }
-      break;
-    }
+    /* Make an entry in the sqlite_master table */
+    v = sqlite3GetVdbe(pParse);
+    if( v==0 ) goto triggerfinish_cleanup;
+    sqlite3BeginWriteOperation(pParse, 0, iDb);
+    z = sqlite3DbStrNDup(db, (char*)pAll->z, pAll->n);
+    sqlite3NestedParse(pParse,
+       "INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
+       db->aDb[iDb].zName, SCHEMA_TABLE(iDb), zName,
+       pTrig->table, z);
+    sqlite3DbFree(db, z);
+    sqlite3ChangeCookie(pParse, iDb);
+    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
+        db, "type='trigger' AND name='%q'", zName), P4_DYNAMIC
+    );
+  }
 
-#if !defined(SQLITE_OMIT_TRIGGER)
-    /* Discard the results.  This is used for SELECT statements inside
-    ** the body of a TRIGGER.  The purpose of such selects is to call
-    ** user-defined functions that have side effects.  We do not care
-    ** about the actual results of the select.
-    */
-    default: {
-      assert( eDest==SRT_Discard );
-      break;
+  if( db->init.busy ){
+    Trigger *pLink = pTrig;
+    Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
+    pTrig = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), pTrig);
+    if( pTrig ){
+      db->mallocFailed = 1;
+    }else if( pLink->pSchema==pLink->pTabSchema ){
+      Table *pTab;
+      int n = sqlite3Strlen30(pLink->table);
+      pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table, n);
+      assert( pTab!=0 );
+      pLink->pNext = pTab->pTrigger;
+      pTab->pTrigger = pLink;
     }
-#endif
   }
 
-  /* Jump to the end of the loop if the LIMIT is reached.
-  */
-  if( p->iLimit>=0 && pOrderBy==0 ){
-    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
-    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, iBreak);
-  }
+triggerfinish_cleanup:
+  sqlite3DeleteTrigger(db, pTrig);
+  assert( !pParse->pNewTrigger );
+  sqlite3DeleteTriggerStep(db, pStepList);
 }
 
 /*
-** Given an expression list, generate a KeyInfo structure that records
-** the collating sequence for each expression in that expression list.
+** Turn a SELECT statement (that the pSelect parameter points to) into
+** a trigger step.  Return a pointer to a TriggerStep structure.
 **
-** If the ExprList is an ORDER BY or GROUP BY clause then the resulting
-** KeyInfo structure is appropriate for initializing a virtual index to
-** implement that clause.  If the ExprList is the result set of a SELECT
-** then the KeyInfo structure is appropriate for initializing a virtual
-** index to implement a DISTINCT test.
+** The parser calls this routine when it finds a SELECT statement in
+** body of a TRIGGER.  
+*/
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
+  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
+  if( pTriggerStep==0 ) {
+    sqlite3SelectDelete(db, pSelect);
+    return 0;
+  }
+  pTriggerStep->op = TK_SELECT;
+  pTriggerStep->pSelect = pSelect;
+  pTriggerStep->orconf = OE_Default;
+  return pTriggerStep;
+}
+
+/*
+** Allocate space to hold a new trigger step.  The allocated space
+** holds both the TriggerStep object and the TriggerStep.target.z string.
 **
-** Space to hold the KeyInfo structure is obtain from malloc.  The calling
-** function is responsible for seeing that this structure is eventually
-** freed.  Add the KeyInfo structure to the P4 field of an opcode using
-** P4_KEYINFO_HANDOFF is the usual way of dealing with this.
+** If an OOM error occurs, NULL is returned and db->mallocFailed is set.
 */
-static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
-  sqlite3 *db = pParse->db;
-  int nExpr;
-  KeyInfo *pInfo;
-  struct ExprList_item *pItem;
-  int i;
+static TriggerStep *triggerStepAllocate(
+  sqlite3 *db,                /* Database connection */
+  u8 op,                      /* Trigger opcode */
+  Token *pName                /* The target name */
+){
+  TriggerStep *pTriggerStep;
 
-  nExpr = pList->nExpr;
-  pInfo = sqlite3DbMallocZero(db, sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) );
-  if( pInfo ){
-    pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr];
-    pInfo->nField = nExpr;
-    pInfo->enc = ENC(db);
-    for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
-      CollSeq *pColl;
-      pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
-      if( !pColl ){
-        pColl = db->pDfltColl;
-      }
-      pInfo->aColl[i] = pColl;
-      pInfo->aSortOrder[i] = pItem->sortOrder;
-    }
+  pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep) + pName->n);
+  if( pTriggerStep ){
+    char *z = (char*)&pTriggerStep[1];
+    memcpy(z, pName->z, pName->n);
+    pTriggerStep->target.z = z;
+    pTriggerStep->target.n = pName->n;
+    pTriggerStep->op = op;
   }
-  return pInfo;
+  return pTriggerStep;
 }
 
-
 /*
-** If the inner loop was generated using a non-null pOrderBy argument,
-** then the results were placed in a sorter.  After the loop is terminated
-** we need to run the sorter and output the results.  The following
-** routine generates the code needed to do that.
+** Build a trigger step out of an INSERT statement.  Return a pointer
+** to the new trigger step.
+**
+** The parser calls this routine when it sees an INSERT inside the
+** body of a trigger.
 */
-static void generateSortTail(
-  Parse *pParse,    /* Parsing context */
-  Select *p,        /* The SELECT statement */
-  Vdbe *v,          /* Generate code into this VDBE */
-  int nColumn,      /* Number of columns of data */
-  SelectDest *pDest /* Write the sorted results here */
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(
+  sqlite3 *db,        /* The database connection */
+  Token *pTableName,  /* Name of the table into which we insert */
+  IdList *pColumn,    /* List of columns in pTableName to insert into */
+  ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
+  Select *pSelect,    /* A SELECT statement that supplies values */
+  u8 orconf           /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
 ){
-  int brk = sqlite3VdbeMakeLabel(v);
-  int cont = sqlite3VdbeMakeLabel(v);
-  int addr;
-  int iTab;
-  int pseudoTab = 0;
-  ExprList *pOrderBy = p->pOrderBy;
+  TriggerStep *pTriggerStep;
 
-  int eDest = pDest->eDest;
-  int iParm = pDest->iParm;
+  assert(pEList == 0 || pSelect == 0);
+  assert(pEList != 0 || pSelect != 0 || db->mallocFailed);
 
-  int regRow;
-  int regRowid;
+  pTriggerStep = triggerStepAllocate(db, TK_INSERT, pTableName);
+  if( pTriggerStep ){
+    pTriggerStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
+    pTriggerStep->pIdList = pColumn;
+    pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
+    pTriggerStep->orconf = orconf;
+  }else{
+    sqlite3IdListDelete(db, pColumn);
+  }
+  sqlite3ExprListDelete(db, pEList);
+  sqlite3SelectDelete(db, pSelect);
 
-  iTab = pOrderBy->iECursor;
-  if( eDest==SRT_Callback || eDest==SRT_Subroutine ){
-    pseudoTab = pParse->nTab++;
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nColumn);
-    sqlite3VdbeAddOp2(v, OP_OpenPseudo, pseudoTab, eDest==SRT_Callback);
+  return pTriggerStep;
+}
+
+/*
+** Construct a trigger step that implements an UPDATE statement and return
+** a pointer to that trigger step.  The parser calls this routine when it
+** sees an UPDATE statement inside the body of a CREATE TRIGGER.
+*/
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerUpdateStep(
+  sqlite3 *db,         /* The database connection */
+  Token *pTableName,   /* Name of the table to be updated */
+  ExprList *pEList,    /* The SET clause: list of column and new values */
+  Expr *pWhere,        /* The WHERE clause */
+  u8 orconf            /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
+){
+  TriggerStep *pTriggerStep;
+
+  pTriggerStep = triggerStepAllocate(db, TK_UPDATE, pTableName);
+  if( pTriggerStep ){
+    pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
+    pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
+    pTriggerStep->orconf = orconf;
   }
-  addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, brk);
-  codeOffset(v, p, cont);
-  regRow = sqlite3GetTempReg(pParse);
-  regRowid = sqlite3GetTempReg(pParse);
-  sqlite3VdbeAddOp3(v, OP_Column, iTab, pOrderBy->nExpr + 1, regRow);
-  switch( eDest ){
-    case SRT_Table:
-    case SRT_EphemTab: {
-      sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, regRowid);
-      sqlite3VdbeAddOp3(v, OP_Insert, iParm, regRow, regRowid);
-      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
-      break;
-    }
-#ifndef SQLITE_OMIT_SUBQUERY
-    case SRT_Set: {
-      int j1;
-      assert( nColumn==1 );
-      j1 = sqlite3VdbeAddOp1(v, OP_IsNull, regRow);
-      sqlite3VdbeAddOp4(v, OP_MakeRecord, regRow, 1, regRowid, &p->affinity, 1);
-      sqlite3ExprCacheAffinityChange(pParse, regRow, 1);
-      sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, regRowid);
-      sqlite3VdbeJumpHere(v, j1);
-      break;
-    }
-    case SRT_Mem: {
-      assert( nColumn==1 );
-      sqlite3ExprCodeMove(pParse, regRow, iParm);
-      /* The LIMIT clause will terminate the loop for us */
-      break;
-    }
-#endif
-    case SRT_Callback:
-    case SRT_Subroutine: {
-      int i;
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, regRowid);
-      sqlite3VdbeAddOp3(v, OP_Insert, pseudoTab, regRow, regRowid);
-      for(i=0; i<nColumn; i++){
-        assert( regRow!=pDest->iMem+i );
-        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
-      }
-      if( eDest==SRT_Callback ){
-        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
-        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_Gosub, 0, iParm);
-      }
-      break;
-    }
-    default: {
-      /* Do nothing */
-      break;
-    }
+  sqlite3ExprListDelete(db, pEList);
+  sqlite3ExprDelete(db, pWhere);
+  return pTriggerStep;
+}
+
+/*
+** Construct a trigger step that implements a DELETE statement and return
+** a pointer to that trigger step.  The parser calls this routine when it
+** sees a DELETE statement inside the body of a CREATE TRIGGER.
+*/
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(
+  sqlite3 *db,            /* Database connection */
+  Token *pTableName,      /* The table from which rows are deleted */
+  Expr *pWhere            /* The WHERE clause */
+){
+  TriggerStep *pTriggerStep;
+
+  pTriggerStep = triggerStepAllocate(db, TK_DELETE, pTableName);
+  if( pTriggerStep ){
+    pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
+    pTriggerStep->orconf = OE_Default;
   }
-  sqlite3ReleaseTempReg(pParse, regRow);
-  sqlite3ReleaseTempReg(pParse, regRowid);
+  sqlite3ExprDelete(db, pWhere);
+  return pTriggerStep;
+}
 
-  /* Jump to the end of the loop when the LIMIT is reached
-  */
-  if( p->iLimit>=0 ){
-    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
-    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, brk);
+/* 
+** Recursively delete a Trigger structure
+*/
+SQLITE_PRIVATE void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){
+  if( pTrigger==0 ) return;
+  sqlite3DeleteTriggerStep(db, pTrigger->step_list);
+  sqlite3DbFree(db, pTrigger->zName);
+  sqlite3DbFree(db, pTrigger->table);
+  sqlite3ExprDelete(db, pTrigger->pWhen);
+  sqlite3IdListDelete(db, pTrigger->pColumns);
+  sqlite3DbFree(db, pTrigger);
+}
+
+/*
+** This function is called to drop a trigger from the database schema. 
+**
+** This may be called directly from the parser and therefore identifies
+** the trigger by name.  The sqlite3DropTriggerPtr() routine does the
+** same job as this routine except it takes a pointer to the trigger
+** instead of the trigger name.
+**/
+SQLITE_PRIVATE void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr){
+  Trigger *pTrigger = 0;
+  int i;
+  const char *zDb;
+  const char *zName;
+  int nName;
+  sqlite3 *db = pParse->db;
+
+  if( db->mallocFailed ) goto drop_trigger_cleanup;
+  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    goto drop_trigger_cleanup;
   }
 
-  /* The bottom of the loop
-  */
-  sqlite3VdbeResolveLabel(v, cont);
-  sqlite3VdbeAddOp2(v, OP_Next, iTab, addr);
-  sqlite3VdbeResolveLabel(v, brk);
-  if( eDest==SRT_Callback || eDest==SRT_Subroutine ){
-    sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0);
+  assert( pName->nSrc==1 );
+  zDb = pName->a[0].zDatabase;
+  zName = pName->a[0].zName;
+  nName = sqlite3Strlen30(zName);
+  for(i=OMIT_TEMPDB; i<db->nDb; i++){
+    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
+    if( zDb && sqlite3StrICmp(db->aDb[j].zName, zDb) ) continue;
+    pTrigger = sqlite3HashFind(&(db->aDb[j].pSchema->trigHash), zName, nName);
+    if( pTrigger ) break;
+  }
+  if( !pTrigger ){
+    if( !noErr ){
+      sqlite3ErrorMsg(pParse, "no such trigger: %S", pName, 0);
+    }
+    goto drop_trigger_cleanup;
   }
+  sqlite3DropTriggerPtr(pParse, pTrigger);
 
+drop_trigger_cleanup:
+  sqlite3SrcListDelete(db, pName);
 }
 
 /*
-** Return a pointer to a string containing the 'declaration type' of the
-** expression pExpr. The string may be treated as static by the caller.
-**
-** The declaration type is the exact datatype definition extracted from the
-** original CREATE TABLE statement if the expression is a column. The
-** declaration type for a ROWID field is INTEGER. Exactly when an expression
-** is considered a column can be complex in the presence of subqueries. The
-** result-set expression in all of the following SELECT statements is 
-** considered a column by this function.
-**
-**   SELECT col FROM tbl;
-**   SELECT (SELECT col FROM tbl;
-**   SELECT (SELECT col FROM tbl);
-**   SELECT abc FROM (SELECT col AS abc FROM tbl);
-** 
-** The declaration type for any expression other than a column is NULL.
+** Return a pointer to the Table structure for the table that a trigger
+** is set on.
 */
-static const char *columnType(
-  NameContext *pNC, 
-  Expr *pExpr,
-  const char **pzOriginDb,
-  const char **pzOriginTab,
-  const char **pzOriginCol
-){
-  char const *zType = 0;
-  char const *zOriginDb = 0;
-  char const *zOriginTab = 0;
-  char const *zOriginCol = 0;
-  int j;
-  if( pExpr==0 || pNC->pSrcList==0 ) return 0;
+static Table *tableOfTrigger(Trigger *pTrigger){
+  int n = sqlite3Strlen30(pTrigger->table);
+  return sqlite3HashFind(&pTrigger->pTabSchema->tblHash, pTrigger->table, n);
+}
 
-  switch( pExpr->op ){
-    case TK_AGG_COLUMN:
-    case TK_COLUMN: {
-      /* The expression is a column. Locate the table the column is being
-      ** extracted from in NameContext.pSrcList. This table may be real
-      ** database table or a subquery.
-      */
-      Table *pTab = 0;            /* Table structure column is extracted from */
-      Select *pS = 0;             /* Select the column is extracted from */
-      int iCol = pExpr->iColumn;  /* Index of column in pTab */
-      while( pNC && !pTab ){
-        SrcList *pTabList = pNC->pSrcList;
-        for(j=0;j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable;j++);
-        if( j<pTabList->nSrc ){
-          pTab = pTabList->a[j].pTab;
-          pS = pTabList->a[j].pSelect;
-        }else{
-          pNC = pNC->pNext;
-        }
-      }
 
-      if( pTab==0 ){
-        /* FIX ME:
-        ** This can occurs if you have something like "SELECT new.x;" inside
-        ** a trigger.  In other words, if you reference the special "new"
-        ** table in the result set of a select.  We do not have a good way
-        ** to find the actual table type, so call it "TEXT".  This is really
-        ** something of a bug, but I do not know how to fix it.
-        **
-        ** This code does not produce the correct answer - it just prevents
-        ** a segfault.  See ticket #1229.
-        */
-        zType = "TEXT";
-        break;
-      }
+/*
+** Drop a trigger given a pointer to that trigger. 
+*/
+SQLITE_PRIVATE void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
+  Table   *pTable;
+  Vdbe *v;
+  sqlite3 *db = pParse->db;
+  int iDb;
 
-      assert( pTab );
-      if( pS ){
-        /* The "table" is actually a sub-select or a view in the FROM clause
-        ** of the SELECT statement. Return the declaration type and origin
-        ** data for the result-set column of the sub-select.
-        */
-        if( iCol>=0 && iCol<pS->pEList->nExpr ){
-          /* If iCol is less than zero, then the expression requests the
-          ** rowid of the sub-select or view. This expression is legal (see 
-          ** test case misc2.2.2) - it always evaluates to NULL.
-          */
-          NameContext sNC;
-          Expr *p = pS->pEList->a[iCol].pExpr;
-          sNC.pSrcList = pS->pSrc;
-          sNC.pNext = 0;
-          sNC.pParse = pNC->pParse;
-          zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
-        }
-      }else if( pTab->pSchema ){
-        /* A real table */
-        assert( !pS );
-        if( iCol<0 ) iCol = pTab->iPKey;
-        assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
-        if( iCol<0 ){
-          zType = "INTEGER";
-          zOriginCol = "rowid";
-        }else{
-          zType = pTab->aCol[iCol].zType;
-          zOriginCol = pTab->aCol[iCol].zName;
-        }
-        zOriginTab = pTab->zName;
-        if( pNC->pParse ){
-          int iDb = sqlite3SchemaToIndex(pNC->pParse->db, pTab->pSchema);
-          zOriginDb = pNC->pParse->db->aDb[iDb].zName;
-        }
-      }
-      break;
-    }
-#ifndef SQLITE_OMIT_SUBQUERY
-    case TK_SELECT: {
-      /* The expression is a sub-select. Return the declaration type and
-      ** origin info for the single column in the result set of the SELECT
-      ** statement.
-      */
-      NameContext sNC;
-      Select *pS = pExpr->pSelect;
-      Expr *p = pS->pEList->a[0].pExpr;
-      sNC.pSrcList = pS->pSrc;
-      sNC.pNext = pNC;
-      sNC.pParse = pNC->pParse;
-      zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
-      break;
+  iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
+  assert( iDb>=0 && iDb<db->nDb );
+  pTable = tableOfTrigger(pTrigger);
+  assert( pTable );
+  assert( pTable->pSchema==pTrigger->pSchema || iDb==1 );
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  {
+    int code = SQLITE_DROP_TRIGGER;
+    const char *zDb = db->aDb[iDb].zName;
+    const char *zTab = SCHEMA_TABLE(iDb);
+    if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
+    if( sqlite3AuthCheck(pParse, code, pTrigger->zName, pTable->zName, zDb) ||
+      sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
+      return;
     }
+  }
 #endif
+
+  /* Generate code to destroy the database record of the trigger.
+  */
+  assert( pTable!=0 );
+  if( (v = sqlite3GetVdbe(pParse))!=0 ){
+    int base;
+    static const VdbeOpList dropTrigger[] = {
+      { OP_Rewind,     0, ADDR(9),  0},
+      { OP_String8,    0, 1,        0}, /* 1 */
+      { OP_Column,     0, 1,        2},
+      { OP_Ne,         2, ADDR(8),  1},
+      { OP_String8,    0, 1,        0}, /* 4: "trigger" */
+      { OP_Column,     0, 0,        2},
+      { OP_Ne,         2, ADDR(8),  1},
+      { OP_Delete,     0, 0,        0},
+      { OP_Next,       0, ADDR(1),  0}, /* 8 */
+    };
+
+    sqlite3BeginWriteOperation(pParse, 0, iDb);
+    sqlite3OpenMasterTable(pParse, iDb);
+    base = sqlite3VdbeAddOpList(v,  ArraySize(dropTrigger), dropTrigger);
+    sqlite3VdbeChangeP4(v, base+1, pTrigger->zName, 0);
+    sqlite3VdbeChangeP4(v, base+4, "trigger", P4_STATIC);
+    sqlite3ChangeCookie(pParse, iDb);
+    sqlite3VdbeAddOp2(v, OP_Close, 0, 0);
+    sqlite3VdbeAddOp4(v, OP_DropTrigger, iDb, 0, 0, pTrigger->zName, 0);
+    if( pParse->nMem<3 ){
+      pParse->nMem = 3;
+    }
   }
-  
-  if( pzOriginDb ){
-    assert( pzOriginTab && pzOriginCol );
-    *pzOriginDb = zOriginDb;
-    *pzOriginTab = zOriginTab;
-    *pzOriginCol = zOriginCol;
+}
+
+/*
+** Remove a trigger from the hash tables of the sqlite* pointer.
+*/
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const char *zName){
+  Hash *pHash = &(db->aDb[iDb].pSchema->trigHash);
+  Trigger *pTrigger;
+  pTrigger = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), 0);
+  if( ALWAYS(pTrigger) ){
+    if( pTrigger->pSchema==pTrigger->pTabSchema ){
+      Table *pTab = tableOfTrigger(pTrigger);
+      Trigger **pp;
+      for(pp=&pTab->pTrigger; *pp!=pTrigger; pp=&((*pp)->pNext));
+      *pp = (*pp)->pNext;
+    }
+    sqlite3DeleteTrigger(db, pTrigger);
+    db->flags |= SQLITE_InternChanges;
   }
-  return zType;
 }
 
 /*
-** Generate code that will tell the VDBE the declaration types of columns
-** in the result set.
+** pEList is the SET clause of an UPDATE statement.  Each entry
+** in pEList is of the format <id>=<expr>.  If any of the entries
+** in pEList have an <id> which matches an identifier in pIdList,
+** then return TRUE.  If pIdList==NULL, then it is considered a
+** wildcard that matches anything.  Likewise if pEList==NULL then
+** it matches anything so always return true.  Return false only
+** if there is no match.
 */
-static void generateColumnTypes(
-  Parse *pParse,      /* Parser context */
-  SrcList *pTabList,  /* List of tables */
-  ExprList *pEList    /* Expressions defining the result set */
+static int checkColumnOverlap(IdList *pIdList, ExprList *pEList){
+  int e;
+  if( pIdList==0 || NEVER(pEList==0) ) return 1;
+  for(e=0; e<pEList->nExpr; e++){
+    if( sqlite3IdListIndex(pIdList, pEList->a[e].zName)>=0 ) return 1;
+  }
+  return 0; 
+}
+
+/*
+** Return a list of all triggers on table pTab if there exists at least
+** one trigger that must be fired when an operation of type 'op' is 
+** performed on the table, and, if that operation is an UPDATE, if at
+** least one of the columns in pChanges is being modified.
+*/
+SQLITE_PRIVATE Trigger *sqlite3TriggersExist(
+  Parse *pParse,          /* Parse context */
+  Table *pTab,            /* The table the contains the triggers */
+  int op,                 /* one of TK_DELETE, TK_INSERT, TK_UPDATE */
+  ExprList *pChanges,     /* Columns that change in an UPDATE statement */
+  int *pMask              /* OUT: Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
 ){
-#ifndef SQLITE_OMIT_DECLTYPE
-  Vdbe *v = pParse->pVdbe;
-  int i;
-  NameContext sNC;
-  sNC.pSrcList = pTabList;
-  sNC.pParse = pParse;
-  for(i=0; i<pEList->nExpr; i++){
-    Expr *p = pEList->a[i].pExpr;
-    const char *zType;
-#ifdef SQLITE_ENABLE_COLUMN_METADATA
-    const char *zOrigDb = 0;
-    const char *zOrigTab = 0;
-    const char *zOrigCol = 0;
-    zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol);
+  int mask = 0;
+  Trigger *pList = sqlite3TriggerList(pParse, pTab);
+  Trigger *p;
+  assert( pList==0 || IsVirtual(pTab)==0 );
+  for(p=pList; p; p=p->pNext){
+    if( p->op==op && checkColumnOverlap(p->pColumns, pChanges) ){
+      mask |= p->tr_tm;
+    }
+  }
+  if( pMask ){
+    *pMask = mask;
+  }
+  return (mask ? pList : 0);
+}
+
+/*
+** Convert the pStep->target token into a SrcList and return a pointer
+** to that SrcList.
+**
+** This routine adds a specific database name, if needed, to the target when
+** forming the SrcList.  This prevents a trigger in one database from
+** referring to a target in another database.  An exception is when the
+** trigger is in TEMP in which case it can refer to any other database it
+** wants.
+*/
+static SrcList *targetSrcList(
+  Parse *pParse,       /* The parsing context */
+  TriggerStep *pStep   /* The trigger containing the target token */
+){
+  int iDb;             /* Index of the database to use */
+  SrcList *pSrc;       /* SrcList to be returned */
 
-    /* The vdbe must make its own copy of the column-type and other 
-    ** column specific strings, in case the schema is reset before this
-    ** virtual machine is deleted.
-    */
-    sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, P4_TRANSIENT);
-    sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, P4_TRANSIENT);
-    sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, P4_TRANSIENT);
-#else
-    zType = columnType(&sNC, p, 0, 0, 0);
-#endif
-    sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, P4_TRANSIENT);
+  pSrc = sqlite3SrcListAppend(pParse->db, 0, &pStep->target, 0);
+  if( pSrc ){
+    assert( pSrc->nSrc>0 );
+    assert( pSrc->a!=0 );
+    iDb = sqlite3SchemaToIndex(pParse->db, pStep->pTrig->pSchema);
+    if( iDb==0 || iDb>=2 ){
+      sqlite3 *db = pParse->db;
+      assert( iDb<pParse->db->nDb );
+      pSrc->a[pSrc->nSrc-1].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);
+    }
   }
-#endif /* SQLITE_OMIT_DECLTYPE */
+  return pSrc;
 }
 
 /*
-** Generate code that will tell the VDBE the names of columns
-** in the result set.  This information is used to provide the
-** azCol[] values in the callback.
+** Generate VDBE code for the statements inside the body of a single 
+** trigger.
 */
-static void generateColumnNames(
-  Parse *pParse,      /* Parser context */
-  SrcList *pTabList,  /* List of tables */
-  ExprList *pEList    /* Expressions defining the result set */
+static int codeTriggerProgram(
+  Parse *pParse,            /* The parser context */
+  TriggerStep *pStepList,   /* List of statements inside the trigger body */
+  int orconf                /* Conflict algorithm. (OE_Abort, etc) */  
 ){
+  TriggerStep *pStep;
   Vdbe *v = pParse->pVdbe;
-  int i, j;
   sqlite3 *db = pParse->db;
-  int fullNames, shortNames;
-
-#ifndef SQLITE_OMIT_EXPLAIN
-  /* If this is an EXPLAIN, skip this step */
-  if( pParse->explain ){
-    return;
-  }
-#endif
 
+  assert( pParse->pTriggerTab && pParse->pToplevel );
+  assert( pStepList );
   assert( v!=0 );
-  if( pParse->colNamesSet || v==0 || db->mallocFailed ) return;
-  pParse->colNamesSet = 1;
-  fullNames = (db->flags & SQLITE_FullColNames)!=0;
-  shortNames = (db->flags & SQLITE_ShortColNames)!=0;
-  sqlite3VdbeSetNumCols(v, pEList->nExpr);
-  for(i=0; i<pEList->nExpr; i++){
-    Expr *p;
-    p = pEList->a[i].pExpr;
-    if( p==0 ) continue;
-    if( pEList->a[i].zName ){
-      char *zName = pEList->a[i].zName;
-      sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, strlen(zName));
-      continue;
-    }
-    if( p->op==TK_COLUMN && pTabList ){
-      Table *pTab;
-      char *zCol;
-      int iCol = p->iColumn;
-      for(j=0; j<pTabList->nSrc && pTabList->a[j].iCursor!=p->iTable; j++){}
-      assert( j<pTabList->nSrc );
-      pTab = pTabList->a[j].pTab;
-      if( iCol<0 ) iCol = pTab->iPKey;
-      assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
-      if( iCol<0 ){
-        zCol = "rowid";
-      }else{
-        zCol = pTab->aCol[iCol].zName;
+  for(pStep=pStepList; pStep; pStep=pStep->pNext){
+    /* Figure out the ON CONFLICT policy that will be used for this step
+    ** of the trigger program. If the statement that caused this trigger
+    ** to fire had an explicit ON CONFLICT, then use it. Otherwise, use
+    ** the ON CONFLICT policy that was specified as part of the trigger
+    ** step statement. Example:
+    **
+    **   CREATE TRIGGER AFTER INSERT ON t1 BEGIN;
+    **     INSERT OR REPLACE INTO t2 VALUES(new.a, new.b);
+    **   END;
+    **
+    **   INSERT INTO t1 ... ;            -- insert into t2 uses REPLACE policy
+    **   INSERT OR IGNORE INTO t1 ... ;  -- insert into t2 uses IGNORE policy
+    */
+    pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
+
+    switch( pStep->op ){
+      case TK_UPDATE: {
+        sqlite3Update(pParse, 
+          targetSrcList(pParse, pStep),
+          sqlite3ExprListDup(db, pStep->pExprList, 0), 
+          sqlite3ExprDup(db, pStep->pWhere, 0), 
+          pParse->eOrconf
+        );
+        break;
       }
-      if( !shortNames && !fullNames && p->span.z && p->span.z[0] ){
-        sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n);
-      }else if( fullNames || (!shortNames && pTabList->nSrc>1) ){
-        char *zName = 0;
-        char *zTab;
- 
-        zTab = pTabList->a[j].zAlias;
-        if( fullNames || zTab==0 ) zTab = pTab->zName;
-        sqlite3SetString(&zName, zTab, ".", zCol, (char*)0);
-        sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, P4_DYNAMIC);
-      }else{
-        sqlite3VdbeSetColName(v, i, COLNAME_NAME, zCol, strlen(zCol));
+      case TK_INSERT: {
+        sqlite3Insert(pParse, 
+          targetSrcList(pParse, pStep),
+          sqlite3ExprListDup(db, pStep->pExprList, 0), 
+          sqlite3SelectDup(db, pStep->pSelect, 0), 
+          sqlite3IdListDup(db, pStep->pIdList), 
+          pParse->eOrconf
+        );
+        break;
       }
-    }else if( p->span.z && p->span.z[0] ){
-      sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n);
-      /* sqlite3VdbeCompressSpace(v, addr); */
-    }else{
-      char zName[30];
-      assert( p->op!=TK_COLUMN || pTabList==0 );
-      sqlite3_snprintf(sizeof(zName), zName, "column%d", i+1);
-      sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, 0);
+      case TK_DELETE: {
+        sqlite3DeleteFrom(pParse, 
+          targetSrcList(pParse, pStep),
+          sqlite3ExprDup(db, pStep->pWhere, 0)
+        );
+        break;
+      }
+      default: assert( pStep->op==TK_SELECT ); {
+        SelectDest sDest;
+        Select *pSelect = sqlite3SelectDup(db, pStep->pSelect, 0);
+        sqlite3SelectDestInit(&sDest, SRT_Discard, 0);
+        sqlite3Select(pParse, pSelect, &sDest);
+        sqlite3SelectDelete(db, pSelect);
+        break;
+      }
+    } 
+    if( pStep->op!=TK_SELECT ){
+      sqlite3VdbeAddOp0(v, OP_ResetCount);
     }
   }
-  generateColumnTypes(pParse, pTabList, pEList);
+
+  return 0;
 }
 
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
+#ifdef SQLITE_DEBUG
 /*
-** Name of the connection operator, used for error messages.
+** This function is used to add VdbeComment() annotations to a VDBE
+** program. It is not used in production code, only for debugging.
 */
-static const char *selectOpName(int id){
-  char *z;
-  switch( id ){
-    case TK_ALL:       z = "UNION ALL";   break;
-    case TK_INTERSECT: z = "INTERSECT";   break;
-    case TK_EXCEPT:    z = "EXCEPT";      break;
-    default:           z = "UNION";       break;
+static const char *onErrorText(int onError){
+  switch( onError ){
+    case OE_Abort:    return "abort";
+    case OE_Rollback: return "rollback";
+    case OE_Fail:     return "fail";
+    case OE_Replace:  return "replace";
+    case OE_Ignore:   return "ignore";
+    case OE_Default:  return "default";
   }
-  return z;
+  return "n/a";
 }
-#endif /* SQLITE_OMIT_COMPOUND_SELECT */
+#endif
 
 /*
-** Forward declaration
+** Parse context structure pFrom has just been used to create a sub-vdbe
+** (trigger program). If an error has occurred, transfer error information
+** from pFrom to pTo.
 */
-static int prepSelectStmt(Parse*, Select*);
+static void transferParseError(Parse *pTo, Parse *pFrom){
+  assert( pFrom->zErrMsg==0 || pFrom->nErr );
+  assert( pTo->zErrMsg==0 || pTo->nErr );
+  if( pTo->nErr==0 ){
+    pTo->zErrMsg = pFrom->zErrMsg;
+    pTo->nErr = pFrom->nErr;
+  }else{
+    sqlite3DbFree(pFrom->db, pFrom->zErrMsg);
+  }
+}
 
 /*
-** Given a SELECT statement, generate a Table structure that describes
-** the result set of that SELECT.
+** Create and populate a new TriggerPrg object with a sub-program 
+** implementing trigger pTrigger with ON CONFLICT policy orconf.
 */
-SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){
-  Table *pTab;
-  int i, j;
-  ExprList *pEList;
-  Column *aCol, *pCol;
-  sqlite3 *db = pParse->db;
+static TriggerPrg *codeRowTrigger(
+  Parse *pParse,       /* Current parse context */
+  Trigger *pTrigger,   /* Trigger to code */
+  Table *pTab,         /* The table pTrigger is attached to */
+  int orconf           /* ON CONFLICT policy to code trigger program with */
+){
+  Parse *pTop = sqlite3ParseToplevel(pParse);
+  sqlite3 *db = pParse->db;   /* Database handle */
+  TriggerPrg *pPrg;           /* Value to return */
+  Expr *pWhen = 0;            /* Duplicate of trigger WHEN expression */
+  Vdbe *v;                    /* Temporary VM */
+  NameContext sNC;            /* Name context for sub-vdbe */
+  SubProgram *pProgram = 0;   /* Sub-vdbe for trigger program */
+  Parse *pSubParse;           /* Parse context for sub-vdbe */
+  int iEndTrigger = 0;        /* Label to jump to if WHEN is false */
+
+  assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+
+  /* Allocate the TriggerPrg and SubProgram objects. To ensure that they
+  ** are freed if an error occurs, link them into the Parse.pTriggerPrg 
+  ** list of the top-level Parse object sooner rather than later.  */
+  pPrg = sqlite3DbMallocZero(db, sizeof(TriggerPrg));
+  if( !pPrg ) return 0;
+  pPrg->pNext = pTop->pTriggerPrg;
+  pTop->pTriggerPrg = pPrg;
+  pPrg->pProgram = pProgram = sqlite3DbMallocZero(db, sizeof(SubProgram));
+  if( !pProgram ) return 0;
+  pProgram->nRef = 1;
+  pPrg->pTrigger = pTrigger;
+  pPrg->orconf = orconf;
+  pPrg->oldmask = 0xffffffff;
+
+  /* Allocate and populate a new Parse context to use for coding the 
+  ** trigger sub-program.  */
+  pSubParse = sqlite3StackAllocZero(db, sizeof(Parse));
+  if( !pSubParse ) return 0;
+  memset(&sNC, 0, sizeof(sNC));
+  sNC.pParse = pSubParse;
+  pSubParse->db = db;
+  pSubParse->pTriggerTab = pTab;
+  pSubParse->pToplevel = pTop;
+  pSubParse->zAuthContext = pTrigger->zName;
+  pSubParse->eTriggerOp = pTrigger->op;
+
+  v = sqlite3GetVdbe(pSubParse);
+  if( v ){
+    VdbeComment((v, "Start: %s.%s (%s %s%s%s ON %s)", 
+      pTrigger->zName, onErrorText(orconf),
+      (pTrigger->tr_tm==TRIGGER_BEFORE ? "BEFORE" : "AFTER"),
+        (pTrigger->op==TK_UPDATE ? "UPDATE" : ""),
+        (pTrigger->op==TK_INSERT ? "INSERT" : ""),
+        (pTrigger->op==TK_DELETE ? "DELETE" : ""),
+      pTab->zName
+    ));
+#ifndef SQLITE_OMIT_TRACE
+    sqlite3VdbeChangeP4(v, -1, 
+      sqlite3MPrintf(db, "-- TRIGGER %s", pTrigger->zName), P4_DYNAMIC
+    );
+#endif
 
-  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
-  if( prepSelectStmt(pParse, pSelect) ){
-    return 0;
-  }
-  if( sqlite3SelectResolve(pParse, pSelect, 0) ){
-    return 0;
-  }
-  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
-  if( pTab==0 ){
-    return 0;
-  }
-  pTab->nRef = 1;
-  pTab->zName = zTabName ? sqlite3DbStrDup(db, zTabName) : 0;
-  pEList = pSelect->pEList;
-  pTab->nCol = pEList->nExpr;
-  assert( pTab->nCol>0 );
-  pTab->aCol = aCol = sqlite3DbMallocZero(db, sizeof(pTab->aCol[0])*pTab->nCol);
-  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
-    Expr *p, *pR;
-    char *zType;
-    char *zName;
-    int nName;
-    CollSeq *pColl;
-    int cnt;
-    NameContext sNC;
-    
-    /* Get an appropriate name for the column
-    */
-    p = pEList->a[i].pExpr;
-    assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 );
-    if( (zName = pEList->a[i].zName)!=0 ){
-      /* If the column contains an "AS <name>" phrase, use <name> as the name */
-      zName = sqlite3DbStrDup(db, zName);
-    }else if( p->op==TK_DOT 
-              && (pR=p->pRight)!=0 && pR->token.z && pR->token.z[0] ){
-      /* For columns of the from A.B use B as the name */
-      zName = sqlite3MPrintf(db, "%T", &pR->token);
-    }else if( p->span.z && p->span.z[0] ){
-      /* Use the original text of the column expression as its name */
-      zName = sqlite3MPrintf(db, "%T", &p->span);
-    }else{
-      /* If all else fails, make up a name */
-      zName = sqlite3MPrintf(db, "column%d", i+1);
+    /* If one was specified, code the WHEN clause. If it evaluates to false
+    ** (or NULL) the sub-vdbe is immediately halted by jumping to the 
+    ** OP_Halt inserted at the end of the program.  */
+    if( pTrigger->pWhen ){
+      pWhen = sqlite3ExprDup(db, pTrigger->pWhen, 0);
+      if( SQLITE_OK==sqlite3ResolveExprNames(&sNC, pWhen) 
+       && db->mallocFailed==0 
+      ){
+        iEndTrigger = sqlite3VdbeMakeLabel(v);
+        sqlite3ExprIfFalse(pSubParse, pWhen, iEndTrigger, SQLITE_JUMPIFNULL);
+      }
+      sqlite3ExprDelete(db, pWhen);
     }
-    if( !zName || db->mallocFailed ){
-      db->mallocFailed = 1;
-      sqlite3_free(zName);
-      sqlite3DeleteTable(pTab);
-      return 0;
+
+    /* Code the trigger program into the sub-vdbe. */
+    codeTriggerProgram(pSubParse, pTrigger->step_list, orconf);
+
+    /* Insert an OP_Halt at the end of the sub-program. */
+    if( iEndTrigger ){
+      sqlite3VdbeResolveLabel(v, iEndTrigger);
     }
-    sqlite3Dequote(zName);
+    sqlite3VdbeAddOp0(v, OP_Halt);
+    VdbeComment((v, "End: %s.%s", pTrigger->zName, onErrorText(orconf)));
 
-    /* Make sure the column name is unique.  If the name is not unique,
-    ** append a integer to the name so that it becomes unique.
-    */
-    nName = strlen(zName);
-    for(j=cnt=0; j<i; j++){
-      if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){
-        zName[nName] = 0;
-        zName = sqlite3MPrintf(db, "%z:%d", zName, ++cnt);
-        j = -1;
-        if( zName==0 ) break;
-      }
+    transferParseError(pParse, pSubParse);
+    if( db->mallocFailed==0 ){
+      pProgram->aOp = sqlite3VdbeTakeOpArray(v, &pProgram->nOp, &pTop->nMaxArg);
     }
-    pCol->zName = zName;
+    pProgram->nMem = pSubParse->nMem;
+    pProgram->nCsr = pSubParse->nTab;
+    pProgram->token = (void *)pTrigger;
+    pPrg->oldmask = pSubParse->oldmask;
+    sqlite3VdbeDelete(v);
+  }
 
-    /* Get the typename, type affinity, and collating sequence for the
-    ** column.
-    */
-    memset(&sNC, 0, sizeof(sNC));
-    sNC.pSrcList = pSelect->pSrc;
-    zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
-    pCol->zType = zType;
-    pCol->affinity = sqlite3ExprAffinity(p);
-    pColl = sqlite3ExprCollSeq(pParse, p);
-    if( pColl ){
-      pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
+  assert( !pSubParse->pAinc       && !pSubParse->pZombieTab );
+  assert( !pSubParse->pTriggerPrg && !pSubParse->nMaxArg );
+  sqlite3StackFree(db, pSubParse);
+
+  return pPrg;
+}
+    
+/*
+** Return a pointer to a TriggerPrg object containing the sub-program for
+** trigger pTrigger with default ON CONFLICT algorithm orconf. If no such
+** TriggerPrg object exists, a new object is allocated and populated before
+** being returned.
+*/
+static TriggerPrg *getRowTrigger(
+  Parse *pParse,       /* Current parse context */
+  Trigger *pTrigger,   /* Trigger to code */
+  Table *pTab,         /* The table trigger pTrigger is attached to */
+  int orconf           /* ON CONFLICT algorithm. */
+){
+  Parse *pRoot = sqlite3ParseToplevel(pParse);
+  TriggerPrg *pPrg;
+
+  assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+
+  /* It may be that this trigger has already been coded (or is in the
+  ** process of being coded). If this is the case, then an entry with
+  ** a matching TriggerPrg.pTrigger field will be present somewhere
+  ** in the Parse.pTriggerPrg list. Search for such an entry.  */
+  for(pPrg=pRoot->pTriggerPrg; 
+      pPrg && (pPrg->pTrigger!=pTrigger || pPrg->orconf!=orconf); 
+      pPrg=pPrg->pNext
+  );
+
+  /* If an existing TriggerPrg could not be located, create a new one. */
+  if( !pPrg ){
+    pPrg = codeRowTrigger(pParse, pTrigger, pTab, orconf);
+  }
+
+  return pPrg;
+}
+
+/*
+** Generate code for the trigger program associated with trigger p on 
+** table pTab. The reg, orconf and ignoreJump parameters passed to this
+** function are the same as those described in the header function for
+** sqlite3CodeRowTrigger()
+*/
+SQLITE_PRIVATE void sqlite3CodeRowTriggerDirect(
+  Parse *pParse,       /* Parse context */
+  Trigger *p,          /* Trigger to code */
+  Table *pTab,         /* The table to code triggers from */
+  int reg,             /* Reg array containing OLD.* and NEW.* values */
+  int orconf,          /* ON CONFLICT policy */
+  int ignoreJump       /* Instruction to jump to for RAISE(IGNORE) */
+){
+  Vdbe *v = sqlite3GetVdbe(pParse); /* Main VM */
+  TriggerPrg *pPrg;
+  pPrg = getRowTrigger(pParse, p, pTab, orconf);
+  assert( pPrg || pParse->nErr || pParse->db->mallocFailed );
+
+  /* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program 
+  ** is a pointer to the sub-vdbe containing the trigger program.  */
+  if( pPrg ){
+    sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
+    pPrg->pProgram->nRef++;
+    sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
+    VdbeComment(
+        (v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
+
+    /* Set the P5 operand of the OP_Program instruction to non-zero if
+    ** recursive invocation of this trigger program is disallowed. Recursive
+    ** invocation is disallowed if (a) the sub-program is really a trigger,
+    ** not a foreign key action, and (b) the flag to enable recursive triggers
+    ** is clear.  */
+    sqlite3VdbeChangeP5(v, (u8)(p->zName && !(pParse->db->flags&SQLITE_RecTriggers)));
+  }
+}
+
+/*
+** This is called to code the required FOR EACH ROW triggers for an operation
+** on table pTab. The operation to code triggers for (INSERT, UPDATE or DELETE)
+** is given by the op paramater. The tr_tm parameter determines whether the
+** BEFORE or AFTER triggers are coded. If the operation is an UPDATE, then
+** parameter pChanges is passed the list of columns being modified.
+**
+** If there are no triggers that fire at the specified time for the specified
+** operation on pTab, this function is a no-op.
+**
+** The reg argument is the address of the first in an array of registers 
+** that contain the values substituted for the new.* and old.* references
+** in the trigger program. If N is the number of columns in table pTab
+** (a copy of pTab->nCol), then registers are populated as follows:
+**
+**   Register       Contains
+**   ------------------------------------------------------
+**   reg+0          OLD.rowid
+**   reg+1          OLD.* value of left-most column of pTab
+**   ...            ...
+**   reg+N          OLD.* value of right-most column of pTab
+**   reg+N+1        NEW.rowid
+**   reg+N+2        OLD.* value of left-most column of pTab
+**   ...            ...
+**   reg+N+N+1      NEW.* value of right-most column of pTab
+**
+** For ON DELETE triggers, the registers containing the NEW.* values will
+** never be accessed by the trigger program, so they are not allocated or 
+** populated by the caller (there is no data to populate them with anyway). 
+** Similarly, for ON INSERT triggers the values stored in the OLD.* registers
+** are never accessed, and so are not allocated by the caller. So, for an
+** ON INSERT trigger, the value passed to this function as parameter reg
+** is not a readable register, although registers (reg+N) through 
+** (reg+N+N+1) are.
+**
+** Parameter orconf is the default conflict resolution algorithm for the
+** trigger program to use (REPLACE, IGNORE etc.). Parameter ignoreJump
+** is the instruction that control should jump to if a trigger program
+** raises an IGNORE exception.
+*/
+SQLITE_PRIVATE void sqlite3CodeRowTrigger(
+  Parse *pParse,       /* Parse context */
+  Trigger *pTrigger,   /* List of triggers on table pTab */
+  int op,              /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
+  ExprList *pChanges,  /* Changes list for any UPDATE OF triggers */
+  int tr_tm,           /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
+  Table *pTab,         /* The table to code triggers from */
+  int reg,             /* The first in an array of registers (see above) */
+  int orconf,          /* ON CONFLICT policy */
+  int ignoreJump       /* Instruction to jump to for RAISE(IGNORE) */
+){
+  Trigger *p;          /* Used to iterate through pTrigger list */
+
+  assert( op==TK_UPDATE || op==TK_INSERT || op==TK_DELETE );
+  assert( tr_tm==TRIGGER_BEFORE || tr_tm==TRIGGER_AFTER );
+  assert( (op==TK_UPDATE)==(pChanges!=0) );
+
+  for(p=pTrigger; p; p=p->pNext){
+
+    /* Sanity checking:  The schema for the trigger and for the table are
+    ** always defined.  The trigger must be in the same schema as the table
+    ** or else it must be a TEMP trigger. */
+    assert( p->pSchema!=0 );
+    assert( p->pTabSchema!=0 );
+    assert( p->pSchema==p->pTabSchema 
+         || p->pSchema==pParse->db->aDb[1].pSchema );
+
+    /* Determine whether we should code this trigger */
+    if( p->op==op 
+     && p->tr_tm==tr_tm 
+     && checkColumnOverlap(p->pColumns, pChanges)
+    ){
+      sqlite3CodeRowTriggerDirect(pParse, p, pTab, reg, orconf, ignoreJump);
     }
   }
-  pTab->iPKey = -1;
-  return pTab;
 }
 
 /*
-** Prepare a SELECT statement for processing by doing the following
-** things:
+** Triggers fired by UPDATE or DELETE statements may access values stored
+** in the old.* pseudo-table. This function returns a 32-bit bitmask
+** indicating which columns of the old.* table actually are used by
+** triggers. This information may be used by the caller to avoid having
+** to load the entire old.* record into memory when executing an UPDATE
+** or DELETE command.
 **
-**    (1)  Make sure VDBE cursor numbers have been assigned to every
-**         element of the FROM clause.
+** Bit 0 of the returned mask is set if the left-most column of the
+** table may be accessed using an old.<col> reference. Bit 1 is set if
+** the second leftmost column value is required, and so on. If there
+** are more than 32 columns in the table, and at least one of the columns
+** with an index greater than 32 may be accessed, 0xffffffff is returned.
 **
-**    (2)  Fill in the pTabList->a[].pTab fields in the SrcList that 
-**         defines FROM clause.  When views appear in the FROM clause,
-**         fill pTabList->a[].pSelect with a copy of the SELECT statement
-**         that implements the view.  A copy is made of the view's SELECT
-**         statement so that we can freely modify or delete that statement
-**         without worrying about messing up the presistent representation
-**         of the view.
+** It is not possible to determine if the old.rowid column is accessed
+** by triggers. The caller must always assume that it is.
 **
-**    (3)  Add terms to the WHERE clause to accomodate the NATURAL keyword
-**         on joins and the ON and USING clause of joins.
+** There is no equivalent function for new.* references.
+*/
+SQLITE_PRIVATE u32 sqlite3TriggerOldmask(
+  Parse *pParse,       /* Parse context */
+  Trigger *pTrigger,   /* List of triggers on table pTab */
+  ExprList *pChanges,  /* Changes list for any UPDATE OF triggers */
+  Table *pTab,         /* The table to code triggers from */
+  int orconf           /* Default ON CONFLICT policy for trigger steps */
+){
+  const int op = pChanges ? TK_UPDATE : TK_DELETE;
+  u32 mask = 0;
+  Trigger *p;
+
+  for(p=pTrigger; p; p=p->pNext){
+    if( p->op==op && checkColumnOverlap(p->pColumns,pChanges) ){
+      TriggerPrg *pPrg;
+      pPrg = getRowTrigger(pParse, p, pTab, orconf);
+      if( pPrg ){
+        mask |= pPrg->oldmask;
+      }
+    }
+  }
+
+  return mask;
+}
+
+#endif /* !defined(SQLITE_OMIT_TRIGGER) */
+
+/************** End of trigger.c *********************************************/
+/************** Begin file update.c ******************************************/
+/*
+** 2001 September 15
 **
-**    (4)  Scan the list of columns in the result set (pEList) looking
-**         for instances of the "*" operator or the TABLE.* operator.
-**         If found, expand each "*" to be every column in every table
-**         and TABLE.* to be every column in TABLE.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that are called by the parser
+** to handle UPDATE statements.
 **
-** Return 0 on success.  If there are problems, leave an error message
-** in pParse and return non-zero.
+** $Id: update.c,v 1.207 2009/08/08 18:01:08 drh Exp $
 */
-static int prepSelectStmt(Parse *pParse, Select *p){
-  int i, j, k, rc;
-  SrcList *pTabList;
-  ExprList *pEList;
-  struct SrcList_item *pFrom;
-  sqlite3 *db = pParse->db;
 
-  if( p==0 || p->pSrc==0 || db->mallocFailed ){
-    return 1;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/* Forward declaration */
+static void updateVirtualTable(
+  Parse *pParse,       /* The parsing context */
+  SrcList *pSrc,       /* The virtual table to be modified */
+  Table *pTab,         /* The virtual table */
+  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
+  Expr *pRowidExpr,    /* Expression used to recompute the rowid */
+  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
+  Expr *pWhere         /* WHERE clause of the UPDATE statement */
+);
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+/*
+** The most recently coded instruction was an OP_Column to retrieve the
+** i-th column of table pTab. This routine sets the P4 parameter of the 
+** OP_Column to the default value, if any.
+**
+** The default value of a column is specified by a DEFAULT clause in the 
+** column definition. This was either supplied by the user when the table
+** was created, or added later to the table definition by an ALTER TABLE
+** command. If the latter, then the row-records in the table btree on disk
+** may not contain a value for the column and the default value, taken
+** from the P4 parameter of the OP_Column instruction, is returned instead.
+** If the former, then all row-records are guaranteed to include a value
+** for the column and the P4 value is not required.
+**
+** Column definitions created by an ALTER TABLE command may only have 
+** literal default values specified: a number, null or a string. (If a more
+** complicated default expression value was provided, it is evaluated 
+** when the ALTER TABLE is executed and one of the literal values written
+** into the sqlite_master table.)
+**
+** Therefore, the P4 parameter is only required if the default value for
+** the column is a literal number, string or null. The sqlite3ValueFromExpr()
+** function is capable of transforming these types of expressions into
+** sqlite3_value objects.
+**
+** If parameter iReg is not negative, code an OP_RealAffinity instruction
+** on register iReg. This is used when an equivalent integer value is 
+** stored in place of an 8-byte floating point value in order to save 
+** space.
+*/
+SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i, int iReg){
+  assert( pTab!=0 );
+  if( !pTab->pSelect ){
+    sqlite3_value *pValue;
+    u8 enc = ENC(sqlite3VdbeDb(v));
+    Column *pCol = &pTab->aCol[i];
+    VdbeComment((v, "%s.%s", pTab->zName, pCol->zName));
+    assert( i<pTab->nCol );
+    sqlite3ValueFromExpr(sqlite3VdbeDb(v), pCol->pDflt, enc, 
+                         pCol->affinity, &pValue);
+    if( pValue ){
+      sqlite3VdbeChangeP4(v, -1, (const char *)pValue, P4_MEM);
+    }
+#ifndef SQLITE_OMIT_FLOATING_POINT
+    if( iReg>=0 && pTab->aCol[i].affinity==SQLITE_AFF_REAL ){
+      sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
+    }
+#endif
   }
-  pTabList = p->pSrc;
-  pEList = p->pEList;
+}
 
-  /* Make sure cursor numbers have been assigned to all entries in
-  ** the FROM clause of the SELECT statement.
+/*
+** Process an UPDATE statement.
+**
+**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
+**          \_______/ \________/     \______/       \________________/
+*            onError   pTabList      pChanges             pWhere
+*/
+SQLITE_PRIVATE void sqlite3Update(
+  Parse *pParse,         /* The parser context */
+  SrcList *pTabList,     /* The table in which we should change things */
+  ExprList *pChanges,    /* Things to be changed */
+  Expr *pWhere,          /* The WHERE clause.  May be null */
+  int onError            /* How to handle constraint errors */
+){
+  int i, j;              /* Loop counters */
+  Table *pTab;           /* The table to be updated */
+  int addr = 0;          /* VDBE instruction address of the start of the loop */
+  WhereInfo *pWInfo;     /* Information about the WHERE clause */
+  Vdbe *v;               /* The virtual database engine */
+  Index *pIdx;           /* For looping over indices */
+  int nIdx;              /* Number of indices that need updating */
+  int iCur;              /* VDBE Cursor number of pTab */
+  sqlite3 *db;           /* The database structure */
+  int *aRegIdx = 0;      /* One register assigned to each index to be updated */
+  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
+                         ** an expression for the i-th column of the table.
+                         ** aXRef[i]==-1 if the i-th column is not changed. */
+  int chngRowid;         /* True if the record number is being changed */
+  Expr *pRowidExpr = 0;  /* Expression defining the new record number */
+  int openAll = 0;       /* True if all indices need to be opened */
+  AuthContext sContext;  /* The authorization context */
+  NameContext sNC;       /* The name-context to resolve expressions in */
+  int iDb;               /* Database containing the table being updated */
+  int j1;                /* Addresses of jump instructions */
+  int okOnePass;         /* True for one-pass algorithm without the FIFO */
+  int hasFK;             /* True if foreign key processing is required */
+
+#ifndef SQLITE_OMIT_TRIGGER
+  int isView;                  /* Trying to update a view */
+  Trigger *pTrigger;           /* List of triggers on pTab, if required */
+#endif
+
+  /* Register Allocations */
+  int regRowCount = 0;   /* A count of rows changed */
+  int regOldRowid;       /* The old rowid */
+  int regNewRowid;       /* The new rowid */
+  int regNew;
+  int regOld = 0;
+  int regRowSet = 0;     /* Rowset of rows to be updated */
+  int regRec;            /* Register used for new table record to insert */
+
+  memset(&sContext, 0, sizeof(sContext));
+  db = pParse->db;
+  if( pParse->nErr || db->mallocFailed ){
+    goto update_cleanup;
+  }
+  assert( pTabList->nSrc==1 );
+
+  /* Locate the table which we want to update. 
   */
-  sqlite3SrcListAssignCursors(pParse, p->pSrc);
+  pTab = sqlite3SrcListLookup(pParse, pTabList);
+  if( pTab==0 ) goto update_cleanup;
+  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
 
-  /* Look up every table named in the FROM clause of the select.  If
-  ** an entry of the FROM clause is a subquery instead of a table or view,
-  ** then create a transient table structure to describe the subquery.
+  /* Figure out if we have any triggers and if the table being
+  ** updated is a view.
   */
-  for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
-    Table *pTab;
-    if( pFrom->pTab!=0 ){
-      /* This statement has already been prepared.  There is no need
-      ** to go further. */
-      assert( i==0 );
-      return 0;
+#ifndef SQLITE_OMIT_TRIGGER
+  pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, 0);
+  isView = pTab->pSelect!=0;
+#else
+# define pTrigger 0
+# define isView 0
+#endif
+#ifdef SQLITE_OMIT_VIEW
+# undef isView
+# define isView 0
+#endif
+
+  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
+    goto update_cleanup;
+  }
+  if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
+    goto update_cleanup;
+  }
+  aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
+  if( aXRef==0 ) goto update_cleanup;
+  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
+
+  /* Allocate a cursors for the main database table and for all indices.
+  ** The index cursors might not be used, but if they are used they
+  ** need to occur right after the database cursor.  So go ahead and
+  ** allocate enough space, just in case.
+  */
+  pTabList->a[0].iCursor = iCur = pParse->nTab++;
+  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+    pParse->nTab++;
+  }
+
+  /* Initialize the name-context */
+  memset(&sNC, 0, sizeof(sNC));
+  sNC.pParse = pParse;
+  sNC.pSrcList = pTabList;
+
+  /* Resolve the column names in all the expressions of the
+  ** of the UPDATE statement.  Also find the column index
+  ** for each column to be updated in the pChanges array.  For each
+  ** column to be updated, make sure we have authorization to change
+  ** that column.
+  */
+  chngRowid = 0;
+  for(i=0; i<pChanges->nExpr; i++){
+    if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
+      goto update_cleanup;
     }
-    if( pFrom->zName==0 ){
-#ifndef SQLITE_OMIT_SUBQUERY
-      /* A sub-query in the FROM clause of a SELECT */
-      assert( pFrom->pSelect!=0 );
-      if( pFrom->zAlias==0 ){
-        pFrom->zAlias =
-          sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pFrom->pSelect);
+    for(j=0; j<pTab->nCol; j++){
+      if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
+        if( j==pTab->iPKey ){
+          chngRowid = 1;
+          pRowidExpr = pChanges->a[i].pExpr;
+        }
+        aXRef[j] = i;
+        break;
       }
-      assert( pFrom->pTab==0 );
-      pFrom->pTab = pTab = 
-        sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
-      if( pTab==0 ){
-        return 1;
+    }
+    if( j>=pTab->nCol ){
+      if( sqlite3IsRowid(pChanges->a[i].zName) ){
+        chngRowid = 1;
+        pRowidExpr = pChanges->a[i].pExpr;
+      }else{
+        sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
+        goto update_cleanup;
       }
-      /* The isEphem flag indicates that the Table structure has been
-      ** dynamically allocated and may be freed at any time.  In other words,
-      ** pTab is not pointing to a persistent table structure that defines
-      ** part of the schema. */
-      pTab->isEphem = 1;
+    }
+#ifndef SQLITE_OMIT_AUTHORIZATION
+    {
+      int rc;
+      rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
+                           pTab->aCol[j].zName, db->aDb[iDb].zName);
+      if( rc==SQLITE_DENY ){
+        goto update_cleanup;
+      }else if( rc==SQLITE_IGNORE ){
+        aXRef[j] = -1;
+      }
+    }
 #endif
+  }
+
+  hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngRowid);
+
+  /* Allocate memory for the array aRegIdx[].  There is one entry in the
+  ** array for each index associated with table being updated.  Fill in
+  ** the value with a register number for indices that are to be used
+  ** and with zero for unused indices.
+  */
+  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
+  if( nIdx>0 ){
+    aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
+    if( aRegIdx==0 ) goto update_cleanup;
+  }
+  for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
+    int reg;
+    if( chngRowid ){
+      reg = ++pParse->nMem;
     }else{
-      /* An ordinary table or view name in the FROM clause */
-      assert( pFrom->pTab==0 );
-      pFrom->pTab = pTab = 
-        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
-      if( pTab==0 ){
-        return 1;
-      }
-      pTab->nRef++;
-#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
-      if( pTab->pSelect || IsVirtual(pTab) ){
-        /* We reach here if the named table is a really a view */
-        if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-          return 1;
-        }
-        /* If pFrom->pSelect!=0 it means we are dealing with a
-        ** view within a view.  The SELECT structure has already been
-        ** copied by the outer view so we can skip the copy step here
-        ** in the inner view.
-        */
-        if( pFrom->pSelect==0 ){
-          pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect);
+      reg = 0;
+      for(i=0; i<pIdx->nColumn; i++){
+        if( aXRef[pIdx->aiColumn[i]]>=0 ){
+          reg = ++pParse->nMem;
+          break;
         }
       }
+    }
+    aRegIdx[j] = reg;
+  }
+
+  /* Begin generating code. */
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ) goto update_cleanup;
+  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
+  sqlite3BeginWriteOperation(pParse, 1, iDb);
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  /* Virtual tables must be handled separately */
+  if( IsVirtual(pTab) ){
+    updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
+                       pWhere);
+    pWhere = 0;
+    pTabList = 0;
+    goto update_cleanup;
+  }
+#endif
+
+  /* Allocate required registers. */
+  regOldRowid = regNewRowid = ++pParse->nMem;
+  if( pTrigger || hasFK ){
+    regOld = pParse->nMem + 1;
+    pParse->nMem += pTab->nCol;
+  }
+  if( chngRowid || pTrigger || hasFK ){
+    regNewRowid = ++pParse->nMem;
+  }
+  regNew = pParse->nMem + 1;
+  pParse->nMem += pTab->nCol;
+  regRec = ++pParse->nMem;
+
+  /* Start the view context. */
+  if( isView ){
+    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
+  }
+
+  /* If we are trying to update a view, realize that view into
+  ** a ephemeral table.
+  */
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+  if( isView ){
+    sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
+  }
 #endif
-    }
+
+  /* Resolve the column names in all the expressions in the
+  ** WHERE clause.
+  */
+  if( sqlite3ResolveExprNames(&sNC, pWhere) ){
+    goto update_cleanup;
   }
 
-  /* Process NATURAL keywords, and ON and USING clauses of joins.
+  /* Begin the database scan
   */
-  if( sqliteProcessJoin(pParse, p) ) return 1;
+  sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
+  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0, WHERE_ONEPASS_DESIRED);
+  if( pWInfo==0 ) goto update_cleanup;
+  okOnePass = pWInfo->okOnePass;
 
-  /* For every "*" that occurs in the column list, insert the names of
-  ** all columns in all tables.  And for every TABLE.* insert the names
-  ** of all columns in TABLE.  The parser inserted a special expression
-  ** with the TK_ALL operator for each "*" that it found in the column list.
-  ** The following code just has to locate the TK_ALL expressions and expand
-  ** each one to the list of all columns in all tables.
-  **
-  ** The first loop just checks to see if there are any "*" operators
-  ** that need expanding.
+  /* Remember the rowid of every item to be updated.
   */
-  for(k=0; k<pEList->nExpr; k++){
-    Expr *pE = pEList->a[k].pExpr;
-    if( pE->op==TK_ALL ) break;
-    if( pE->op==TK_DOT && pE->pRight && pE->pRight->op==TK_ALL
-         && pE->pLeft && pE->pLeft->op==TK_ID ) break;
+  sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
+  if( !okOnePass ){
+    regRowSet = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
   }
-  rc = 0;
-  if( k<pEList->nExpr ){
-    /*
-    ** If we get here it means the result set contains one or more "*"
-    ** operators that need to be expanded.  Loop through each expression
-    ** in the result set and expand them one by one.
-    */
-    struct ExprList_item *a = pEList->a;
-    ExprList *pNew = 0;
-    int flags = pParse->db->flags;
-    int longNames = (flags & SQLITE_FullColNames)!=0 &&
-                      (flags & SQLITE_ShortColNames)==0;
 
-    for(k=0; k<pEList->nExpr; k++){
-      Expr *pE = a[k].pExpr;
-      if( pE->op!=TK_ALL &&
-           (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){
-        /* This particular expression does not need to be expanded.
-        */
-        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr, 0);
-        if( pNew ){
-          pNew->a[pNew->nExpr-1].zName = a[k].zName;
-        }else{
-          rc = 1;
-        }
-        a[k].pExpr = 0;
-        a[k].zName = 0;
-      }else{
-        /* This expression is a "*" or a "TABLE.*" and needs to be
-        ** expanded. */
-        int tableSeen = 0;      /* Set to 1 when TABLE matches */
-        char *zTName;            /* text of name of TABLE */
-        if( pE->op==TK_DOT && pE->pLeft ){
-          zTName = sqlite3NameFromToken(db, &pE->pLeft->token);
-        }else{
-          zTName = 0;
-        }
-        for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
-          Table *pTab = pFrom->pTab;
-          char *zTabName = pFrom->zAlias;
-          if( zTabName==0 || zTabName[0]==0 ){ 
-            zTabName = pTab->zName;
-          }
-          if( zTName && (zTabName==0 || zTabName[0]==0 || 
-                 sqlite3StrICmp(zTName, zTabName)!=0) ){
-            continue;
-          }
-          tableSeen = 1;
-          for(j=0; j<pTab->nCol; j++){
-            Expr *pExpr, *pRight;
-            char *zName = pTab->aCol[j].zName;
+  /* End the database scan loop.
+  */
+  sqlite3WhereEnd(pWInfo);
 
-            /* If a column is marked as 'hidden' (currently only possible
-            ** for virtual tables), do not include it in the expanded
-            ** result-set list.
-            */
-            if( IsHiddenColumn(&pTab->aCol[j]) ){
-              assert(IsVirtual(pTab));
-              continue;
-            }
+  /* Initialize the count of updated rows
+  */
+  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
+    regRowCount = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
+  }
 
-            if( i>0 ){
-              struct SrcList_item *pLeft = &pTabList->a[i-1];
-              if( (pLeft[1].jointype & JT_NATURAL)!=0 &&
-                        columnIndex(pLeft->pTab, zName)>=0 ){
-                /* In a NATURAL join, omit the join columns from the 
-                ** table on the right */
-                continue;
-              }
-              if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){
-                /* In a join with a USING clause, omit columns in the
-                ** using clause from the table on the right. */
-                continue;
-              }
-            }
-            pRight = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
-            if( pRight==0 ) break;
-            setQuotedToken(pParse, &pRight->token, zName);
-            if( zTabName && (longNames || pTabList->nSrc>1) ){
-              Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
-              pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-              if( pExpr==0 ) break;
-              setQuotedToken(pParse, &pLeft->token, zTabName);
-              setToken(&pExpr->span, 
-                  sqlite3MPrintf(db, "%s.%s", zTabName, zName));
-              pExpr->span.dyn = 1;
-              pExpr->token.z = 0;
-              pExpr->token.n = 0;
-              pExpr->token.dyn = 0;
-            }else{
-              pExpr = pRight;
-              pExpr->span = pExpr->token;
-              pExpr->span.dyn = 0;
-            }
-            if( longNames ){
-              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pExpr->span);
-            }else{
-              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pRight->token);
-            }
-          }
-        }
-        if( !tableSeen ){
-          if( zTName ){
-            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
-          }else{
-            sqlite3ErrorMsg(pParse, "no tables specified");
-          }
-          rc = 1;
+  if( !isView ){
+    /* 
+    ** Open every index that needs updating.  Note that if any
+    ** index could potentially invoke a REPLACE conflict resolution 
+    ** action, then we need to open all indices because we might need
+    ** to be deleting some records.
+    */
+    if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); 
+    if( onError==OE_Replace ){
+      openAll = 1;
+    }else{
+      openAll = 0;
+      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+        if( pIdx->onError==OE_Replace ){
+          openAll = 1;
+          break;
         }
-        sqlite3_free(zTName);
       }
     }
-    sqlite3ExprListDelete(pEList);
-    p->pEList = pNew;
-  }
-#if SQLITE_MAX_COLUMN
-  if( p->pEList && p->pEList->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
-    sqlite3ErrorMsg(pParse, "too many columns in result set");
-    rc = SQLITE_ERROR;
-  }
-#endif
-  if( db->mallocFailed ){
-    rc = SQLITE_NOMEM;
+    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
+      if( openAll || aRegIdx[i]>0 ){
+        KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
+        sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
+                       (char*)pKey, P4_KEYINFO_HANDOFF);
+        assert( pParse->nTab>iCur+i+1 );
+      }
+    }
   }
-  return rc;
-}
 
-/*
-** pE is a pointer to an expression which is a single term in
-** ORDER BY or GROUP BY clause.
-**
-** If pE evaluates to an integer constant i, then return i.
-** This is an indication to the caller that it should sort
-** by the i-th column of the result set.
-**
-** If pE is a well-formed expression and the SELECT statement
-** is not compound, then return 0.  This indicates to the
-** caller that it should sort by the value of the ORDER BY
-** expression.
-**
-** If the SELECT is compound, then attempt to match pE against
-** result set columns in the left-most SELECT statement.  Return
-** the index i of the matching column, as an indication to the 
-** caller that it should sort by the i-th column.  If there is
-** no match, return -1 and leave an error message in pParse.
-*/
-static int matchOrderByTermToExprList(
-  Parse *pParse,     /* Parsing context for error messages */
-  Select *pSelect,   /* The SELECT statement with the ORDER BY clause */
-  Expr *pE,          /* The specific ORDER BY term */
-  int idx,           /* When ORDER BY term is this */
-  int isCompound,    /* True if this is a compound SELECT */
-  u8 *pHasAgg        /* True if expression contains aggregate functions */
-){
-  int i;             /* Loop counter */
-  ExprList *pEList;  /* The columns of the result set */
-  NameContext nc;    /* Name context for resolving pE */
+  /* Top of the update loop */
+  if( okOnePass ){
+    int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
+    addr = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, a1);
+  }else{
+    addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
+  }
 
+  /* Make cursor iCur point to the record that is being updated. If
+  ** this record does not exist for some reason (deleted by a trigger,
+  ** for example, then jump to the next iteration of the RowSet loop.  */
+  sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
 
-  /* If the term is an integer constant, return the value of that
-  ** constant */
-  pEList = pSelect->pEList;
-  if( sqlite3ExprIsInteger(pE, &i) ){
-    if( i<=0 ){
-      /* If i is too small, make it too big.  That way the calling
-      ** function still sees a value that is out of range, but does
-      ** not confuse the column number with 0 or -1 result code.
-      */
-      i = pEList->nExpr+1;
-    }
-    return i;
+  /* If the record number will change, set register regNewRowid to
+  ** contain the new value. If the record number is not being modified,
+  ** then regNewRowid is the same register as regOldRowid, which is
+  ** already populated.  */
+  assert( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
+  if( chngRowid ){
+    sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
+    sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
   }
 
-  /* If the term is a simple identifier that try to match that identifier
-  ** against a column name in the result set.
-  */
-  if( pE->op==TK_ID || (pE->op==TK_STRING && pE->token.z[0]!='\'') ){
-    sqlite3 *db = pParse->db;
-    char *zCol = sqlite3NameFromToken(db, &pE->token);
-    if( zCol==0 ){
-      return -1;
-    }
-    for(i=0; i<pEList->nExpr; i++){
-      char *zAs = pEList->a[i].zName;
-      if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
-        sqlite3_free(zCol);
-        return i+1;
+  /* If there are triggers on this table, populate an array of registers 
+  ** with the required old.* column data.  */
+  if( hasFK || pTrigger ){
+    u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
+    oldmask |= sqlite3TriggerOldmask(pParse, pTrigger, pChanges, pTab, onError);
+    for(i=0; i<pTab->nCol; i++){
+      if( aXRef[i]<0 || oldmask==0xffffffff || (oldmask & (1<<i)) ){
+        sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regOld+i);
+        sqlite3ColumnDefault(v, pTab, i, regOld+i);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
       }
     }
-    sqlite3_free(zCol);
+    if( chngRowid==0 ){
+      sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
+    }
   }
 
-  /* Resolve all names in the ORDER BY term expression
-  */
-  memset(&nc, 0, sizeof(nc));
-  nc.pParse = pParse;
-  nc.pSrcList = pSelect->pSrc;
-  nc.pEList = pEList;
-  nc.allowAgg = 1;
-  nc.nErr = 0;
-  if( sqlite3ExprResolveNames(&nc, pE) ){
-    if( isCompound ){
-      sqlite3ErrorClear(pParse);
-      return 0;
+  /* Populate the array of registers beginning at regNew with the new
+  ** row data. This array is used to check constaints, create the new
+  ** table and index records, and as the values for any new.* references
+  ** made by triggers.  */
+  for(i=0; i<pTab->nCol; i++){
+    if( i==pTab->iPKey ){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
     }else{
-      return -1;
+      j = aXRef[i];
+      if( j<0 ){
+        sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
+        sqlite3ColumnDefault(v, pTab, i, regNew+i);
+      }else{
+        sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
+      }
     }
   }
-  if( nc.hasAgg && pHasAgg ){
-    *pHasAgg = 1;
+
+  /* Fire any BEFORE UPDATE triggers. This happens before constraints are
+  ** verified. One could argue that this is wrong.  */
+  if( pTrigger ){
+    sqlite3VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
+    sqlite3TableAffinityStr(v, pTab);
+    sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
+        TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);
+
+    /* The row-trigger may have deleted the row being updated. In this
+    ** case, jump to the next row. No updates or AFTER triggers are 
+    ** required. This behaviour - what happens when the row being updated
+    ** is deleted or renamed by a BEFORE trigger - is left undefined in the
+    ** documentation.  */
+    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
   }
 
-  /* For a compound SELECT, we need to try to match the ORDER BY
-  ** expression against an expression in the result set
-  */
-  if( isCompound ){
-    for(i=0; i<pEList->nExpr; i++){
-      if( sqlite3ExprCompare(pEList->a[i].pExpr, pE) ){
-        return i+1;
-      }
+  if( !isView ){
+
+    /* Do constraint checks. */
+    sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
+        aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);
+
+    /* Do FK constraint checks. */
+    if( hasFK ){
+      sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
     }
-  }
-  return 0;
-}
 
+    /* Delete the index entries associated with the current record.  */
+    j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
+    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
+  
+    /* If changing the record number, delete the old record.  */
+    if( hasFK || chngRowid ){
+      sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
+    }
+    sqlite3VdbeJumpHere(v, j1);
 
-/*
-** Analyze and ORDER BY or GROUP BY clause in a simple SELECT statement.
-** Return the number of errors seen.
-**
-** Every term of the ORDER BY or GROUP BY clause needs to be an
-** expression.  If any expression is an integer constant, then
-** that expression is replaced by the corresponding 
-** expression from the result set.
-*/
-static int processOrderGroupBy(
-  Parse *pParse,        /* Parsing context.  Leave error messages here */
-  Select *pSelect,      /* The SELECT statement containing the clause */
-  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */
-  int isOrder,          /* 1 for ORDER BY.  0 for GROUP BY */
-  u8 *pHasAgg           /* Set to TRUE if any term contains an aggregate */
-){
-  int i;
-  sqlite3 *db = pParse->db;
-  ExprList *pEList;
+    if( hasFK ){
+      sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
+    }
+  
+    /* Insert the new index entries and the new record. */
+    sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, aRegIdx, 1, 0, 0);
 
-  if( pOrderBy==0 || pParse->db->mallocFailed ) return 0;
-#if SQLITE_MAX_COLUMN
-  if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
-    const char *zType = isOrder ? "ORDER" : "GROUP";
-    sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType);
-    return 1;
+    /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
+    ** handle rows (possibly in other tables) that refer via a foreign key
+    ** to the row just updated. */ 
+    if( hasFK ){
+      sqlite3FkActions(pParse, pTab, pChanges, regOldRowid);
+    }
   }
-#endif
-  pEList = pSelect->pEList;
-  if( pEList==0 ){
-    return 0;
+
+  /* Increment the row counter 
+  */
+  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
+    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
   }
-  for(i=0; i<pOrderBy->nExpr; i++){
-    int iCol;
-    Expr *pE = pOrderBy->a[i].pExpr;
-    iCol = matchOrderByTermToExprList(pParse, pSelect, pE, i+1, 0, pHasAgg);
-    if( iCol<0 ){
-      return 1;
-    }
-    if( iCol>pEList->nExpr ){
-      const char *zType = isOrder ? "ORDER" : "GROUP";
-      sqlite3ErrorMsg(pParse, 
-         "%r %s BY term out of range - should be "
-         "between 1 and %d", i+1, zType, pEList->nExpr);
-      return 1;
-    }
-    if( iCol>0 ){
-      CollSeq *pColl = pE->pColl;
-      int flags = pE->flags & EP_ExpCollate;
-      sqlite3ExprDelete(pE);
-      pE = sqlite3ExprDup(db, pEList->a[iCol-1].pExpr);
-      pOrderBy->a[i].pExpr = pE;
-      if( pE && pColl && flags ){
-        pE->pColl = pColl;
-        pE->flags |= flags;
-      }
+
+  sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
+      TRIGGER_AFTER, pTab, regOldRowid, onError, addr);
+
+  /* Repeat the above with the next record to be updated, until
+  ** all record selected by the WHERE clause have been updated.
+  */
+  sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
+  sqlite3VdbeJumpHere(v, addr);
+
+  /* Close all tables */
+  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
+    if( openAll || aRegIdx[i]>0 ){
+      sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
     }
   }
-  return 0;
+  sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
+
+  /* Update the sqlite_sequence table by storing the content of the
+  ** maximum rowid counter values recorded while inserting into
+  ** autoincrement tables.
+  */
+  if( pParse->nested==0 && pParse->pTriggerTab==0 ){
+    sqlite3AutoincrementEnd(pParse);
+  }
+
+  /*
+  ** Return the number of rows that were changed. If this routine is 
+  ** generating code because of a call to sqlite3NestedParse(), do not
+  ** invoke the callback function.
+  */
+  if( (db->flags&SQLITE_CountRows) && !pParse->pTriggerTab && !pParse->nested ){
+    sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
+  }
+
+update_cleanup:
+  sqlite3AuthContextPop(&sContext);
+  sqlite3DbFree(db, aRegIdx);
+  sqlite3DbFree(db, aXRef);
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprListDelete(db, pChanges);
+  sqlite3ExprDelete(db, pWhere);
+  return;
 }
+/* Make sure "isView" and other macros defined above are undefined. Otherwise
+** thely may interfere with compilation of other functions in this file
+** (or in another file, if this file becomes part of the amalgamation).  */
+#ifdef isView
+ #undef isView
+#endif
+#ifdef pTrigger
+ #undef pTrigger
+#endif
 
+#ifndef SQLITE_OMIT_VIRTUALTABLE
 /*
-** Analyze and ORDER BY or GROUP BY clause in a SELECT statement.  Return
-** the number of errors seen.
+** Generate code for an UPDATE of a virtual table.
+**
+** The strategy is that we create an ephemerial table that contains
+** for each row to be changed:
+**
+**   (A)  The original rowid of that row.
+**   (B)  The revised rowid for the row. (note1)
+**   (C)  The content of every column in the row.
+**
+** Then we loop over this ephemeral table and for each row in
+** the ephermeral table call VUpdate.
 **
-** The processing depends on whether the SELECT is simple or compound.
-** For a simple SELECT statement, evry term of the ORDER BY or GROUP BY
-** clause needs to be an expression.  If any expression is an integer
-** constant, then that expression is replaced by the corresponding 
-** expression from the result set.
+** When finished, drop the ephemeral table.
 **
-** For compound SELECT statements, every expression needs to be of
-** type TK_COLUMN with a iTable value as given in the 4th parameter.
-** If any expression is an integer, that becomes the column number.
-** Otherwise, match the expression against result set columns from
-** the left-most SELECT.
+** (note1) Actually, if we know in advance that (A) is always the same
+** as (B) we only store (A), then duplicate (A) when pulling
+** it out of the ephemeral table before calling VUpdate.
 */
-static int processCompoundOrderBy(
-  Parse *pParse,        /* Parsing context.  Leave error messages here */
-  Select *pSelect,      /* The SELECT statement containing the ORDER BY */
-  int iTable            /* Output table for compound SELECT statements */
+static void updateVirtualTable(
+  Parse *pParse,       /* The parsing context */
+  SrcList *pSrc,       /* The virtual table to be modified */
+  Table *pTab,         /* The virtual table */
+  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
+  Expr *pRowid,        /* Expression used to recompute the rowid */
+  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
+  Expr *pWhere         /* WHERE clause of the UPDATE statement */
 ){
-  int i;
-  ExprList *pOrderBy;
-  ExprList *pEList;
-  sqlite3 *db;
-  int moreToDo = 1;
+  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
+  ExprList *pEList = 0;     /* The result set of the SELECT statement */
+  Select *pSelect = 0;      /* The SELECT statement */
+  Expr *pExpr;              /* Temporary expression */
+  int ephemTab;             /* Table holding the result of the SELECT */
+  int i;                    /* Loop counter */
+  int addr;                 /* Address of top of loop */
+  int iReg;                 /* First register in set passed to OP_VUpdate */
+  sqlite3 *db = pParse->db; /* Database connection */
+  const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
+  SelectDest dest;
 
-  pOrderBy = pSelect->pOrderBy;
-  if( pOrderBy==0 ) return 0;
-  db = pParse->db;
-#if SQLITE_MAX_COLUMN
-  if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
-    sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause");
-    return 1;
-  }
-#endif
-  for(i=0; i<pOrderBy->nExpr; i++){
-    pOrderBy->a[i].done = 0;
-  }
-  while( pSelect->pPrior ){
-    pSelect = pSelect->pPrior;
+  /* Construct the SELECT statement that will find the new values for
+  ** all updated rows. 
+  */
+  pEList = sqlite3ExprListAppend(pParse, 0, 
+                                 sqlite3CreateIdExpr(pParse, "_rowid_"));
+  if( pRowid ){
+    pEList = sqlite3ExprListAppend(pParse, pEList,
+                                   sqlite3ExprDup(db, pRowid, 0));
   }
-  while( pSelect && moreToDo ){
-    moreToDo = 0;
-    for(i=0; i<pOrderBy->nExpr; i++){
-      int iCol = -1;
-      Expr *pE, *pDup;
-      if( pOrderBy->a[i].done ) continue;
-      pE = pOrderBy->a[i].pExpr;
-      pDup = sqlite3ExprDup(db, pE);
-      if( !db->mallocFailed ){
-        assert(pDup);
-        iCol = matchOrderByTermToExprList(pParse, pSelect, pDup, i+1, 1, 0);
-      }
-      sqlite3ExprDelete(pDup);
-      if( iCol<0 ){
-        return 1;
-      }
-      pEList = pSelect->pEList;
-      if( pEList==0 ){
-        return 1;
-      }
-      if( iCol>pEList->nExpr ){
-        sqlite3ErrorMsg(pParse, 
-           "%r ORDER BY term out of range - should be "
-           "between 1 and %d", i+1, pEList->nExpr);
-        return 1;
-      }
-      if( iCol>0 ){
-        pE->op = TK_COLUMN;
-        pE->iTable = iTable;
-        pE->iAgg = -1;
-        pE->iColumn = iCol-1;
-        pE->pTab = 0;
-        pOrderBy->a[i].done = 1;
-      }else{
-        moreToDo = 1;
-      }
+  assert( pTab->iPKey<0 );
+  for(i=0; i<pTab->nCol; i++){
+    if( aXRef[i]>=0 ){
+      pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
+    }else{
+      pExpr = sqlite3CreateIdExpr(pParse, pTab->aCol[i].zName);
     }
-    pSelect = pSelect->pNext;
+    pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
   }
-  for(i=0; i<pOrderBy->nExpr; i++){
-    if( pOrderBy->a[i].done==0 ){
-      sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any "
-            "column in the result set", i+1);
-      return 1;
-    }
+  pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
+  
+  /* Create the ephemeral table into which the update results will
+  ** be stored.
+  */
+  assert( v );
+  ephemTab = pParse->nTab++;
+  sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
+
+  /* fill the ephemeral table 
+  */
+  sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
+  sqlite3Select(pParse, pSelect, &dest);
+
+  /* Generate code to scan the ephemeral table and call VUpdate. */
+  iReg = ++pParse->nMem;
+  pParse->nMem += pTab->nCol+1;
+  addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
+  sqlite3VdbeAddOp3(v, OP_Column,  ephemTab, 0, iReg);
+  sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
+  for(i=0; i<pTab->nCol; i++){
+    sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
   }
-  return 0;
+  sqlite3VtabMakeWritable(pParse, pTab);
+  sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
+  sqlite3MayAbort(pParse);
+  sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
+  sqlite3VdbeJumpHere(v, addr);
+  sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
+
+  /* Cleanup */
+  sqlite3SelectDelete(db, pSelect);  
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
+/************** End of update.c **********************************************/
+/************** Begin file vacuum.c ******************************************/
 /*
-** Get a VDBE for the given parser context.  Create a new one if necessary.
-** If an error occurs, return NULL and leave a message in pParse.
+** 2003 April 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used to implement the VACUUM command.
+**
+** Most of the code in this file may be omitted by defining the
+** SQLITE_OMIT_VACUUM macro.
+**
+** $Id: vacuum.c,v 1.91 2009/07/02 07:47:33 danielk1977 Exp $
 */
-SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse *pParse){
-  Vdbe *v = pParse->pVdbe;
-  if( v==0 ){
-    v = pParse->pVdbe = sqlite3VdbeCreate(pParse->db);
-#ifndef SQLITE_OMIT_TRACE
-    if( v ){
-      sqlite3VdbeAddOp0(v, OP_Trace);
-    }
-#endif
+
+#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
+/*
+** Execute zSql on database db. Return an error code.
+*/
+static int execSql(sqlite3 *db, const char *zSql){
+  sqlite3_stmt *pStmt;
+  VVA_ONLY( int rc; )
+  if( !zSql ){
+    return SQLITE_NOMEM;
   }
-  return v;
+  if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){
+    return sqlite3_errcode(db);
+  }
+  VVA_ONLY( rc = ) sqlite3_step(pStmt);
+  assert( rc!=SQLITE_ROW );
+  return sqlite3_finalize(pStmt);
 }
 
-
 /*
-** Compute the iLimit and iOffset fields of the SELECT based on the
-** pLimit and pOffset expressions.  pLimit and pOffset hold the expressions
-** that appear in the original SQL statement after the LIMIT and OFFSET
-** keywords.  Or NULL if those keywords are omitted. iLimit and iOffset 
-** are the integer memory register numbers for counters used to compute 
-** the limit and offset.  If there is no limit and/or offset, then 
-** iLimit and iOffset are negative.
-**
-** This routine changes the values of iLimit and iOffset only if
-** a limit or offset is defined by pLimit and pOffset.  iLimit and
-** iOffset should have been preset to appropriate default values
-** (usually but not always -1) prior to calling this routine.
-** Only if pLimit!=0 or pOffset!=0 do the limit registers get
-** redefined.  The UNION ALL operator uses this property to force
-** the reuse of the same limit and offset registers across multiple
-** SELECT statements.
+** Execute zSql on database db. The statement returns exactly
+** one column. Execute this as SQL on the same database.
 */
-static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
-  Vdbe *v = 0;
-  int iLimit = 0;
-  int iOffset;
-  int addr1;
+static int execExecSql(sqlite3 *db, const char *zSql){
+  sqlite3_stmt *pStmt;
+  int rc;
 
-  /* 
-  ** "LIMIT -1" always shows all rows.  There is some
-  ** contraversy about what the correct behavior should be.
-  ** The current implementation interprets "LIMIT 0" to mean
-  ** no rows.
-  */
-  if( p->pLimit ){
-    p->iLimit = iLimit = ++pParse->nMem;
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) return;
-    sqlite3ExprCode(pParse, p->pLimit, iLimit);
-    sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit);
-    VdbeComment((v, "LIMIT counter"));
-    sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak);
-  }
-  if( p->pOffset ){
-    p->iOffset = iOffset = ++pParse->nMem;
-    if( p->pLimit ){
-      pParse->nMem++;   /* Allocate an extra register for limit+offset */
-    }
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) return;
-    sqlite3ExprCode(pParse, p->pOffset, iOffset);
-    sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset);
-    VdbeComment((v, "OFFSET counter"));
-    addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset);
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset);
-    sqlite3VdbeJumpHere(v, addr1);
-    if( p->pLimit ){
-      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
-      VdbeComment((v, "LIMIT+OFFSET"));
-      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit);
-      sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1);
-      sqlite3VdbeJumpHere(v, addr1);
+  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ) return rc;
+
+  while( SQLITE_ROW==sqlite3_step(pStmt) ){
+    rc = execSql(db, (char*)sqlite3_column_text(pStmt, 0));
+    if( rc!=SQLITE_OK ){
+      sqlite3_finalize(pStmt);
+      return rc;
     }
   }
+
+  return sqlite3_finalize(pStmt);
 }
 
 /*
-** Allocate a virtual index to use for sorting.
+** The non-standard VACUUM command is used to clean up the database,
+** collapse free space, etc.  It is modelled after the VACUUM command
+** in PostgreSQL.
+**
+** In version 1.0.x of SQLite, the VACUUM command would call
+** gdbm_reorganize() on all the database tables.  But beginning
+** with 2.0.0, SQLite no longer uses GDBM so this command has
+** become a no-op.
 */
-static void createSortingIndex(Parse *pParse, Select *p, ExprList *pOrderBy){
-  if( pOrderBy ){
-    int addr;
-    assert( pOrderBy->iECursor==0 );
-    pOrderBy->iECursor = pParse->nTab++;
-    addr = sqlite3VdbeAddOp2(pParse->pVdbe, OP_OpenEphemeral,
-                            pOrderBy->iECursor, pOrderBy->nExpr+1);
-    assert( p->addrOpenEphm[2] == -1 );
-    p->addrOpenEphm[2] = addr;
+SQLITE_PRIVATE void sqlite3Vacuum(Parse *pParse){
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( v ){
+    sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0);
   }
+  return;
 }
 
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
-** Return the appropriate collating sequence for the iCol-th column of
-** the result set for the compound-select statement "p".  Return NULL if
-** the column has no default collating sequence.
-**
-** The collating sequence for the compound select is taken from the
-** left-most term of the select that has a collating sequence.
+** This routine implements the OP_Vacuum opcode of the VDBE.
 */
-static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
-  CollSeq *pRet;
-  if( p->pPrior ){
-    pRet = multiSelectCollSeq(pParse, p->pPrior, iCol);
-  }else{
-    pRet = 0;
-  }
-  if( pRet==0 ){
-    pRet = sqlite3ExprCollSeq(pParse, p->pEList->a[iCol].pExpr);
+SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
+  int rc = SQLITE_OK;     /* Return code from service routines */
+  Btree *pMain;           /* The database being vacuumed */
+  Btree *pTemp;           /* The temporary database we vacuum into */
+  char *zSql = 0;         /* SQL statements */
+  int saved_flags;        /* Saved value of the db->flags */
+  int saved_nChange;      /* Saved value of db->nChange */
+  int saved_nTotalChange; /* Saved value of db->nTotalChange */
+  Db *pDb = 0;            /* Database to detach at end of vacuum */
+  int isMemDb;            /* True if vacuuming a :memory: database */
+  int nRes;
+
+  if( !db->autoCommit ){
+    sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
+    return SQLITE_ERROR;
   }
-  return pRet;
-}
-#endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
-/*
-** This routine is called to process a query that is really the union
-** or intersection of two or more separate queries.
-**
-** "p" points to the right-most of the two queries.  the query on the
-** left is p->pPrior.  The left query could also be a compound query
-** in which case this routine will be called recursively. 
-**
-** The results of the total query are to be written into a destination
-** of type eDest with parameter iParm.
-**
-** Example 1:  Consider a three-way compound SQL statement.
-**
-**     SELECT a FROM t1 UNION SELECT b FROM t2 UNION SELECT c FROM t3
-**
-** This statement is parsed up as follows:
-**
-**     SELECT c FROM t3
-**      |
-**      `----->  SELECT b FROM t2
-**                |
-**                `------>  SELECT a FROM t1
-**
-** The arrows in the diagram above represent the Select.pPrior pointer.
-** So if this routine is called with p equal to the t3 query, then
-** pPrior will be the t2 query.  p->op will be TK_UNION in this case.
-**
-** Notice that because of the way SQLite parses compound SELECTs, the
-** individual selects always group from left to right.
-*/
-static int multiSelect(
-  Parse *pParse,        /* Parsing context */
-  Select *p,            /* The right-most of SELECTs to be coded */
-  SelectDest *pDest,    /* What to do with query results */
-  char *aff             /* If eDest is SRT_Union, the affinity string */
-){
-  int rc = SQLITE_OK;   /* Success code from a subroutine */
-  Select *pPrior;       /* Another SELECT immediately to our left */
-  Vdbe *v;              /* Generate code to this VDBE */
-  int nCol;             /* Number of columns in the result set */
-  ExprList *pOrderBy;   /* The ORDER BY clause on p */
-  int aSetP2[2];        /* Set P2 value of these op to number of columns */
-  int nSetP2 = 0;       /* Number of slots in aSetP2[] used */
-  SelectDest dest;      /* Alternative data destination */
+  /* Save the current value of the database flags so that it can be 
+  ** restored before returning. Then set the writable-schema flag, and
+  ** disable CHECK and foreign key constraints.  */
+  saved_flags = db->flags;
+  saved_nChange = db->nChange;
+  saved_nTotalChange = db->nTotalChange;
+  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
+  db->flags &= ~SQLITE_ForeignKeys;
 
-  dest = *pDest;
+  pMain = db->aDb[0].pBt;
+  isMemDb = sqlite3PagerIsMemdb(sqlite3BtreePager(pMain));
 
-  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
-  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
+  /* Attach the temporary database as 'vacuum_db'. The synchronous pragma
+  ** can be set to 'off' for this file, as it is not recovered if a crash
+  ** occurs anyway. The integrity of the database is maintained by a
+  ** (possibly synchronous) transaction opened on the main database before
+  ** sqlite3BtreeCopyFile() is called.
+  **
+  ** An optimisation would be to use a non-journaled pager.
+  ** (Later:) I tried setting "PRAGMA vacuum_db.journal_mode=OFF" but
+  ** that actually made the VACUUM run slower.  Very little journalling
+  ** actually occurs when doing a vacuum since the vacuum_db is initially
+  ** empty.  Only the journal header is written.  Apparently it takes more
+  ** time to parse and run the PRAGMA to turn journalling off than it does
+  ** to write the journal header file.
   */
-  if( p==0 || p->pPrior==0 ){
-    rc = 1;
-    goto multi_select_end;
+  zSql = "ATTACH '' AS vacuum_db;";
+  rc = execSql(db, zSql);
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+  pDb = &db->aDb[db->nDb-1];
+  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
+  pTemp = db->aDb[db->nDb-1].pBt;
+
+  nRes = sqlite3BtreeGetReserve(pMain);
+
+  /* A VACUUM cannot change the pagesize of an encrypted database. */
+#ifdef SQLITE_HAS_CODEC
+  if( db->nextPagesize ){
+    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
+    int nKey;
+    char *zKey;
+    sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
+    if( nKey ) db->nextPagesize = 0;
   }
-  pPrior = p->pPrior;
-  assert( pPrior->pRightmost!=pPrior );
-  assert( pPrior->pRightmost==p->pRightmost );
-  if( pPrior->pOrderBy ){
-    sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before",
-      selectOpName(p->op));
-    rc = 1;
-    goto multi_select_end;
+#endif
+
+  if( sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain), nRes, 0)
+   || (!isMemDb && sqlite3BtreeSetPageSize(pTemp, db->nextPagesize, nRes, 0))
+   || NEVER(db->mallocFailed)
+  ){
+    rc = SQLITE_NOMEM;
+    goto end_of_vacuum;
   }
-  if( pPrior->pLimit ){
-    sqlite3ErrorMsg(pParse,"LIMIT clause should come after %s not before",
-      selectOpName(p->op));
-    rc = 1;
-    goto multi_select_end;
+  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
+  if( rc!=SQLITE_OK ){
+    goto end_of_vacuum;
   }
 
-  /* Make sure we have a valid query engine.  If not, create a new one.
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac>=0 ? db->nextAutovac :
+                                           sqlite3BtreeGetAutoVacuum(pMain));
+#endif
+
+  /* Begin a transaction */
+  rc = execSql(db, "BEGIN EXCLUSIVE;");
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+
+  /* Query the schema of the main database. Create a mirror schema
+  ** in the temporary database.
   */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ){
-    rc = 1;
-    goto multi_select_end;
-  }
+  rc = execExecSql(db, 
+      "SELECT 'CREATE TABLE vacuum_db.' || substr(sql,14) "
+      "  FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'"
+      "   AND rootpage>0"
+  );
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+  rc = execExecSql(db, 
+      "SELECT 'CREATE INDEX vacuum_db.' || substr(sql,14)"
+      "  FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %' ");
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+  rc = execExecSql(db, 
+      "SELECT 'CREATE UNIQUE INDEX vacuum_db.' || substr(sql,21) "
+      "  FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %'");
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
 
-  /* Create the destination temporary table if necessary
+  /* Loop through the tables in the main database. For each, do
+  ** an "INSERT INTO vacuum_db.xxx SELECT * FROM xxx;" to copy
+  ** the contents to the temporary database.
   */
-  if( dest.eDest==SRT_EphemTab ){
-    assert( p->pEList );
-    assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
-    aSetP2[nSetP2++] = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, 0);
-    dest.eDest = SRT_Table;
-  }
+  rc = execExecSql(db, 
+      "SELECT 'INSERT INTO vacuum_db.' || quote(name) "
+      "|| ' SELECT * FROM ' || quote(name) || ';'"
+      "FROM sqlite_master "
+      "WHERE type = 'table' AND name!='sqlite_sequence' "
+      "  AND rootpage>0"
 
-  /* Generate code for the left and right SELECT statements.
+  );
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+
+  /* Copy over the sequence table
   */
-  pOrderBy = p->pOrderBy;
-  switch( p->op ){
-    case TK_ALL: {
-      if( pOrderBy==0 ){
-        int addr = 0;
-        assert( !pPrior->pLimit );
-        pPrior->pLimit = p->pLimit;
-        pPrior->pOffset = p->pOffset;
-        rc = sqlite3Select(pParse, pPrior, &dest, 0, 0, 0, aff);
-        p->pLimit = 0;
-        p->pOffset = 0;
-        if( rc ){
-          goto multi_select_end;
-        }
-        p->pPrior = 0;
-        p->iLimit = pPrior->iLimit;
-        p->iOffset = pPrior->iOffset;
-        if( p->iLimit>=0 ){
-          addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit);
-          VdbeComment((v, "Jump ahead if LIMIT reached"));
-        }
-        rc = sqlite3Select(pParse, p, &dest, 0, 0, 0, aff);
-        p->pPrior = pPrior;
-        if( rc ){
-          goto multi_select_end;
-        }
-        if( addr ){
-          sqlite3VdbeJumpHere(v, addr);
-        }
-        break;
-      }
-      /* For UNION ALL ... ORDER BY fall through to the next case */
-    }
-    case TK_EXCEPT:
-    case TK_UNION: {
-      int unionTab;    /* Cursor number of the temporary table holding result */
-      int op = 0;      /* One of the SRT_ operations to apply to self */
-      int priorOp;     /* The SRT_ operation to apply to prior selects */
-      Expr *pLimit, *pOffset; /* Saved values of p->nLimit and p->nOffset */
-      int addr;
-      SelectDest uniondest;
+  rc = execExecSql(db, 
+      "SELECT 'DELETE FROM vacuum_db.' || quote(name) || ';' "
+      "FROM vacuum_db.sqlite_master WHERE name='sqlite_sequence' "
+  );
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
+  rc = execExecSql(db, 
+      "SELECT 'INSERT INTO vacuum_db.' || quote(name) "
+      "|| ' SELECT * FROM ' || quote(name) || ';' "
+      "FROM vacuum_db.sqlite_master WHERE name=='sqlite_sequence';"
+  );
+  if( rc!=SQLITE_OK ) goto end_of_vacuum;
 
-      priorOp = p->op==TK_ALL ? SRT_Table : SRT_Union;
-      if( dest.eDest==priorOp && pOrderBy==0 && !p->pLimit && !p->pOffset ){
-        /* We can reuse a temporary table generated by a SELECT to our
-        ** right.
-        */
-        unionTab = dest.iParm;
-      }else{
-        /* We will need to create our own temporary table to hold the
-        ** intermediate results.
-        */
-        unionTab = pParse->nTab++;
-        if( processCompoundOrderBy(pParse, p, unionTab) ){
-          rc = 1;
-          goto multi_select_end;
-        }
-        addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);
-        if( priorOp==SRT_Table ){
-          assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
-          aSetP2[nSetP2++] = addr;
-        }else{
-          assert( p->addrOpenEphm[0] == -1 );
-          p->addrOpenEphm[0] = addr;
-          p->pRightmost->usesEphm = 1;
-        }
-        createSortingIndex(pParse, p, pOrderBy);
-        assert( p->pEList );
-      }
 
-      /* Code the SELECT statements to our left
-      */
-      assert( !pPrior->pOrderBy );
-      sqlite3SelectDestInit(&uniondest, priorOp, unionTab);
-      rc = sqlite3Select(pParse, pPrior, &uniondest, 0, 0, 0, aff);
-      if( rc ){
-        goto multi_select_end;
-      }
+  /* Copy the triggers, views, and virtual tables from the main database
+  ** over to the temporary database.  None of these objects has any
+  ** associated storage, so all we have to do is copy their entries
+  ** from the SQLITE_MASTER table.
+  */
+  rc = execSql(db,
+      "INSERT INTO vacuum_db.sqlite_master "
+      "  SELECT type, name, tbl_name, rootpage, sql"
+      "    FROM sqlite_master"
+      "   WHERE type='view' OR type='trigger'"
+      "      OR (type='table' AND rootpage=0)"
+  );
+  if( rc ) goto end_of_vacuum;
 
-      /* Code the current SELECT statement
-      */
-      switch( p->op ){
-         case TK_EXCEPT:  op = SRT_Except;   break;
-         case TK_UNION:   op = SRT_Union;    break;
-         case TK_ALL:     op = SRT_Table;    break;
-      }
-      p->pPrior = 0;
-      p->pOrderBy = 0;
-      p->disallowOrderBy = pOrderBy!=0;
-      pLimit = p->pLimit;
-      p->pLimit = 0;
-      pOffset = p->pOffset;
-      p->pOffset = 0;
-      uniondest.eDest = op;
-      rc = sqlite3Select(pParse, p, &uniondest, 0, 0, 0, aff);
-      /* Query flattening in sqlite3Select() might refill p->pOrderBy.
-      ** Be sure to delete p->pOrderBy, therefore, to avoid a memory leak. */
-      sqlite3ExprListDelete(p->pOrderBy);
-      p->pPrior = pPrior;
-      p->pOrderBy = pOrderBy;
-      sqlite3ExprDelete(p->pLimit);
-      p->pLimit = pLimit;
-      p->pOffset = pOffset;
-      p->iLimit = -1;
-      p->iOffset = -1;
-      if( rc ){
-        goto multi_select_end;
-      }
+  /* At this point, unless the main db was completely empty, there is now a
+  ** transaction open on the vacuum database, but not on the main database.
+  ** Open a btree level transaction on the main database. This allows a
+  ** call to sqlite3BtreeCopyFile(). The main database btree level
+  ** transaction is then committed, so the SQL level never knows it was
+  ** opened for writing. This way, the SQL transaction used to create the
+  ** temporary database never needs to be committed.
+  */
+  {
+    u32 meta;
+    int i;
 
+    /* This array determines which meta meta values are preserved in the
+    ** vacuum.  Even entries are the meta value number and odd entries
+    ** are an increment to apply to the meta value after the vacuum.
+    ** The increment is used to increase the schema cookie so that other
+    ** connections to the same database will know to reread the schema.
+    */
+    static const unsigned char aCopy[] = {
+       BTREE_SCHEMA_VERSION,     1,  /* Add one to the old schema cookie */
+       BTREE_DEFAULT_CACHE_SIZE, 0,  /* Preserve the default page cache size */
+       BTREE_TEXT_ENCODING,      0,  /* Preserve the text encoding */
+       BTREE_USER_VERSION,       0,  /* Preserve the user version */
+    };
 
-      /* Convert the data in the temporary table into whatever form
-      ** it is that we currently need.
-      */      
-      if( dest.eDest!=priorOp || unionTab!=dest.iParm ){
-        int iCont, iBreak, iStart;
-        assert( p->pEList );
-        if( dest.eDest==SRT_Callback ){
-          Select *pFirst = p;
-          while( pFirst->pPrior ) pFirst = pFirst->pPrior;
-          generateColumnNames(pParse, 0, pFirst->pEList);
-        }
-        iBreak = sqlite3VdbeMakeLabel(v);
-        iCont = sqlite3VdbeMakeLabel(v);
-        computeLimitRegisters(pParse, p, iBreak);
-        sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak);
-        iStart = sqlite3VdbeCurrentAddr(v);
-        selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
-                        pOrderBy, -1, &dest, iCont, iBreak, 0);
-        sqlite3VdbeResolveLabel(v, iCont);
-        sqlite3VdbeAddOp2(v, OP_Next, unionTab, iStart);
-        sqlite3VdbeResolveLabel(v, iBreak);
-        sqlite3VdbeAddOp2(v, OP_Close, unionTab, 0);
-      }
-      break;
+    assert( 1==sqlite3BtreeIsInTrans(pTemp) );
+    assert( 1==sqlite3BtreeIsInTrans(pMain) );
+
+    /* Copy Btree meta values */
+    for(i=0; i<ArraySize(aCopy); i+=2){
+      /* GetMeta() and UpdateMeta() cannot fail in this context because
+      ** we already have page 1 loaded into cache and marked dirty. */
+      sqlite3BtreeGetMeta(pMain, aCopy[i], &meta);
+      rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]);
+      if( NEVER(rc!=SQLITE_OK) ) goto end_of_vacuum;
     }
-    case TK_INTERSECT: {
-      int tab1, tab2;
-      int iCont, iBreak, iStart;
-      Expr *pLimit, *pOffset;
-      int addr;
-      SelectDest intersectdest;
-      int r1;
 
-      /* INTERSECT is different from the others since it requires
-      ** two temporary tables.  Hence it has its own case.  Begin
-      ** by allocating the tables we will need.
-      */
-      tab1 = pParse->nTab++;
-      tab2 = pParse->nTab++;
-      if( processCompoundOrderBy(pParse, p, tab1) ){
-        rc = 1;
-        goto multi_select_end;
-      }
-      createSortingIndex(pParse, p, pOrderBy);
+    rc = sqlite3BtreeCopyFile(pMain, pTemp);
+    if( rc!=SQLITE_OK ) goto end_of_vacuum;
+    rc = sqlite3BtreeCommit(pTemp);
+    if( rc!=SQLITE_OK ) goto end_of_vacuum;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    sqlite3BtreeSetAutoVacuum(pMain, sqlite3BtreeGetAutoVacuum(pTemp));
+#endif
+  }
 
-      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab1, 0);
-      assert( p->addrOpenEphm[0] == -1 );
-      p->addrOpenEphm[0] = addr;
-      p->pRightmost->usesEphm = 1;
-      assert( p->pEList );
+  assert( rc==SQLITE_OK );
+  rc = sqlite3BtreeSetPageSize(pMain, sqlite3BtreeGetPageSize(pTemp), nRes,1);
 
-      /* Code the SELECTs to our left into temporary table "tab1".
-      */
-      sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1);
-      rc = sqlite3Select(pParse, pPrior, &intersectdest, 0, 0, 0, aff);
-      if( rc ){
-        goto multi_select_end;
-      }
+end_of_vacuum:
+  /* Restore the original value of db->flags */
+  db->flags = saved_flags;
+  db->nChange = saved_nChange;
+  db->nTotalChange = saved_nTotalChange;
 
-      /* Code the current SELECT into temporary table "tab2"
-      */
-      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab2, 0);
-      assert( p->addrOpenEphm[1] == -1 );
-      p->addrOpenEphm[1] = addr;
-      p->pPrior = 0;
-      pLimit = p->pLimit;
-      p->pLimit = 0;
-      pOffset = p->pOffset;
-      p->pOffset = 0;
-      intersectdest.iParm = tab2;
-      rc = sqlite3Select(pParse, p, &intersectdest, 0, 0, 0, aff);
-      p->pPrior = pPrior;
-      sqlite3ExprDelete(p->pLimit);
-      p->pLimit = pLimit;
-      p->pOffset = pOffset;
-      if( rc ){
-        goto multi_select_end;
-      }
+  /* Currently there is an SQL level transaction open on the vacuum
+  ** database. No locks are held on any other files (since the main file
+  ** was committed at the btree level). So it safe to end the transaction
+  ** by manually setting the autoCommit flag to true and detaching the
+  ** vacuum database. The vacuum_db journal file is deleted when the pager
+  ** is closed by the DETACH.
+  */
+  db->autoCommit = 1;
 
-      /* Generate code to take the intersection of the two temporary
-      ** tables.
-      */
-      assert( p->pEList );
-      if( dest.eDest==SRT_Callback ){
-        Select *pFirst = p;
-        while( pFirst->pPrior ) pFirst = pFirst->pPrior;
-        generateColumnNames(pParse, 0, pFirst->pEList);
-      }
-      iBreak = sqlite3VdbeMakeLabel(v);
-      iCont = sqlite3VdbeMakeLabel(v);
-      computeLimitRegisters(pParse, p, iBreak);
-      sqlite3VdbeAddOp2(v, OP_Rewind, tab1, iBreak);
-      r1 = sqlite3GetTempReg(pParse);
-      iStart = sqlite3VdbeAddOp2(v, OP_RowKey, tab1, r1);
-      sqlite3VdbeAddOp3(v, OP_NotFound, tab2, iCont, r1);
-      sqlite3ReleaseTempReg(pParse, r1);
-      selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
-                      pOrderBy, -1, &dest, iCont, iBreak, 0);
-      sqlite3VdbeResolveLabel(v, iCont);
-      sqlite3VdbeAddOp2(v, OP_Next, tab1, iStart);
-      sqlite3VdbeResolveLabel(v, iBreak);
-      sqlite3VdbeAddOp2(v, OP_Close, tab2, 0);
-      sqlite3VdbeAddOp2(v, OP_Close, tab1, 0);
-      break;
-    }
+  if( pDb ){
+    sqlite3BtreeClose(pDb->pBt);
+    pDb->pBt = 0;
+    pDb->pSchema = 0;
   }
 
-  /* Make sure all SELECTs in the statement have the same number of elements
-  ** in their result sets.
-  */
-  assert( p->pEList && pPrior->pEList );
-  if( p->pEList->nExpr!=pPrior->pEList->nExpr ){
-    sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s"
-      " do not have the same number of result columns", selectOpName(p->op));
-    rc = 1;
-    goto multi_select_end;
-  }
+  sqlite3ResetInternalSchema(db, 0);
 
-  /* Set the number of columns in temporary tables
-  */
-  nCol = p->pEList->nExpr;
-  while( nSetP2 ){
-    sqlite3VdbeChangeP2(v, aSetP2[--nSetP2], nCol);
-  }
+  return rc;
+}
+#endif  /* SQLITE_OMIT_VACUUM && SQLITE_OMIT_ATTACH */
 
-  /* Compute collating sequences used by either the ORDER BY clause or
-  ** by any temporary tables needed to implement the compound select.
-  ** Attach the KeyInfo structure to all temporary tables.  Invoke the
-  ** ORDER BY processing if there is an ORDER BY clause.
-  **
-  ** This section is run by the right-most SELECT statement only.
-  ** SELECT statements to the left always skip this part.  The right-most
-  ** SELECT might also skip this part if it has no ORDER BY clause and
-  ** no temp tables are required.
-  */
-  if( pOrderBy || p->usesEphm ){
-    int i;                        /* Loop counter */
-    KeyInfo *pKeyInfo;            /* Collating sequence for the result set */
-    Select *pLoop;                /* For looping through SELECT statements */
-    int nKeyCol;                  /* Number of entries in pKeyInfo->aCol[] */
-    CollSeq **apColl;             /* For looping through pKeyInfo->aColl[] */
-    CollSeq **aCopy;              /* A copy of pKeyInfo->aColl[] */
+/************** End of vacuum.c **********************************************/
+/************** Begin file vtab.c ********************************************/
+/*
+** 2006 June 10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used to help implement virtual tables.
+**
+** $Id: vtab.c,v 1.94 2009/08/08 18:01:08 drh Exp $
+*/
+#ifndef SQLITE_OMIT_VIRTUALTABLE
 
-    assert( p->pRightmost==p );
-    nKeyCol = nCol + (pOrderBy ? pOrderBy->nExpr : 0);
-    pKeyInfo = sqlite3DbMallocZero(pParse->db,
-                       sizeof(*pKeyInfo)+nKeyCol*(sizeof(CollSeq*) + 1));
-    if( !pKeyInfo ){
-      rc = SQLITE_NOMEM;
-      goto multi_select_end;
+/*
+** The actual function that does the work of creating a new module.
+** This function implements the sqlite3_create_module() and
+** sqlite3_create_module_v2() interfaces.
+*/
+static int createModule(
+  sqlite3 *db,                    /* Database in which module is registered */
+  const char *zName,              /* Name assigned to this module */
+  const sqlite3_module *pModule,  /* The definition of the module */
+  void *pAux,                     /* Context pointer for xCreate/xConnect */
+  void (*xDestroy)(void *)        /* Module destructor function */
+){
+  int rc, nName;
+  Module *pMod;
+
+  sqlite3_mutex_enter(db->mutex);
+  nName = sqlite3Strlen30(zName);
+  pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
+  if( pMod ){
+    Module *pDel;
+    char *zCopy = (char *)(&pMod[1]);
+    memcpy(zCopy, zName, nName+1);
+    pMod->zName = zCopy;
+    pMod->pModule = pModule;
+    pMod->pAux = pAux;
+    pMod->xDestroy = xDestroy;
+    pDel = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
+    if( pDel && pDel->xDestroy ){
+      pDel->xDestroy(pDel->pAux);
+    }
+    sqlite3DbFree(db, pDel);
+    if( pDel==pMod ){
+      db->mallocFailed = 1;
     }
+    sqlite3ResetInternalSchema(db, 0);
+  }else if( xDestroy ){
+    xDestroy(pAux);
+  }
+  rc = sqlite3ApiExit(db, SQLITE_OK);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+
+/*
+** External API function used to create a new virtual-table module.
+*/
+SQLITE_API int sqlite3_create_module(
+  sqlite3 *db,                    /* Database in which module is registered */
+  const char *zName,              /* Name assigned to this module */
+  const sqlite3_module *pModule,  /* The definition of the module */
+  void *pAux                      /* Context pointer for xCreate/xConnect */
+){
+  return createModule(db, zName, pModule, pAux, 0);
+}
+
+/*
+** External API function used to create a new virtual-table module.
+*/
+SQLITE_API int sqlite3_create_module_v2(
+  sqlite3 *db,                    /* Database in which module is registered */
+  const char *zName,              /* Name assigned to this module */
+  const sqlite3_module *pModule,  /* The definition of the module */
+  void *pAux,                     /* Context pointer for xCreate/xConnect */
+  void (*xDestroy)(void *)        /* Module destructor function */
+){
+  return createModule(db, zName, pModule, pAux, xDestroy);
+}
+
+/*
+** Lock the virtual table so that it cannot be disconnected.
+** Locks nest.  Every lock should have a corresponding unlock.
+** If an unlock is omitted, resources leaks will occur.  
+**
+** If a disconnect is attempted while a virtual table is locked,
+** the disconnect is deferred until all locks have been removed.
+*/
+SQLITE_PRIVATE void sqlite3VtabLock(VTable *pVTab){
+  pVTab->nRef++;
+}
+
 
-    pKeyInfo->enc = ENC(pParse->db);
-    pKeyInfo->nField = nCol;
+/*
+** pTab is a pointer to a Table structure representing a virtual-table.
+** Return a pointer to the VTable object used by connection db to access 
+** this virtual-table, if one has been created, or NULL otherwise.
+*/
+SQLITE_PRIVATE VTable *sqlite3GetVTable(sqlite3 *db, Table *pTab){
+  VTable *pVtab;
+  assert( IsVirtual(pTab) );
+  for(pVtab=pTab->pVTable; pVtab && pVtab->db!=db; pVtab=pVtab->pNext);
+  return pVtab;
+}
 
-    for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){
-      *apColl = multiSelectCollSeq(pParse, p, i);
-      if( 0==*apColl ){
-        *apColl = pParse->db->pDfltColl;
-      }
-    }
+/*
+** Decrement the ref-count on a virtual table object. When the ref-count
+** reaches zero, call the xDisconnect() method to delete the object.
+*/
+SQLITE_PRIVATE void sqlite3VtabUnlock(VTable *pVTab){
+  sqlite3 *db = pVTab->db;
 
-    for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
-      for(i=0; i<2; i++){
-        int addr = pLoop->addrOpenEphm[i];
-        if( addr<0 ){
-          /* If [0] is unused then [1] is also unused.  So we can
-          ** always safely abort as soon as the first unused slot is found */
-          assert( pLoop->addrOpenEphm[1]<0 );
-          break;
-        }
-        sqlite3VdbeChangeP2(v, addr, nCol);
-        sqlite3VdbeChangeP4(v, addr, (char*)pKeyInfo, P4_KEYINFO);
-        pLoop->addrOpenEphm[i] = -1;
-      }
-    }
+  assert( db );
+  assert( pVTab->nRef>0 );
+  assert( sqlite3SafetyCheckOk(db) );
 
-    if( pOrderBy ){
-      struct ExprList_item *pOTerm = pOrderBy->a;
-      int nOrderByExpr = pOrderBy->nExpr;
-      int addr;
-      u8 *pSortOrder;
-
-      /* Reuse the same pKeyInfo for the ORDER BY as was used above for
-      ** the compound select statements.  Except we have to change out the
-      ** pKeyInfo->aColl[] values.  Some of the aColl[] values will be
-      ** reused when constructing the pKeyInfo for the ORDER BY, so make
-      ** a copy.  Sufficient space to hold both the nCol entries for
-      ** the compound select and the nOrderbyExpr entries for the ORDER BY
-      ** was allocated above.  But we need to move the compound select
-      ** entries out of the way before constructing the ORDER BY entries.
-      ** Move the compound select entries into aCopy[] where they can be
-      ** accessed and reused when constructing the ORDER BY entries.
-      ** Because nCol might be greater than or less than nOrderByExpr
-      ** we have to use memmove() when doing the copy.
-      */
-      aCopy = &pKeyInfo->aColl[nOrderByExpr];
-      pSortOrder = pKeyInfo->aSortOrder = (u8*)&aCopy[nCol];
-      memmove(aCopy, pKeyInfo->aColl, nCol*sizeof(CollSeq*));
-
-      apColl = pKeyInfo->aColl;
-      for(i=0; i<nOrderByExpr; i++, pOTerm++, apColl++, pSortOrder++){
-        Expr *pExpr = pOTerm->pExpr;
-        if( (pExpr->flags & EP_ExpCollate) ){
-          assert( pExpr->pColl!=0 );
-          *apColl = pExpr->pColl;
-        }else{
-          *apColl = aCopy[pExpr->iColumn];
-        }
-        *pSortOrder = pOTerm->sortOrder;
+  pVTab->nRef--;
+  if( pVTab->nRef==0 ){
+    sqlite3_vtab *p = pVTab->pVtab;
+    if( p ){
+#ifdef SQLITE_DEBUG
+      if( pVTab->db->magic==SQLITE_MAGIC_BUSY ){
+        (void)sqlite3SafetyOff(db);
+        p->pModule->xDisconnect(p);
+        (void)sqlite3SafetyOn(db);
+      } else
+#endif
+      {
+        p->pModule->xDisconnect(p);
       }
-      assert( p->pRightmost==p );
-      assert( p->addrOpenEphm[2]>=0 );
-      addr = p->addrOpenEphm[2];
-      sqlite3VdbeChangeP2(v, addr, p->pOrderBy->nExpr+2);
-      pKeyInfo->nField = nOrderByExpr;
-      sqlite3VdbeChangeP4(v, addr, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
-      pKeyInfo = 0;
-      generateSortTail(pParse, p, v, p->pEList->nExpr, &dest);
     }
-
-    sqlite3_free(pKeyInfo);
+    sqlite3DbFree(db, pVTab);
   }
-
-multi_select_end:
-  pDest->iMem = dest.iMem;
-  pDest->nMem = dest.nMem;
-  return rc;
 }
-#endif /* SQLITE_OMIT_COMPOUND_SELECT */
-
-#ifndef SQLITE_OMIT_VIEW
-/* Forward Declarations */
-static void substExprList(sqlite3*, ExprList*, int, ExprList*);
-static void substSelect(sqlite3*, Select *, int, ExprList *);
 
 /*
-** Scan through the expression pExpr.  Replace every reference to
-** a column in table number iTable with a copy of the iColumn-th
-** entry in pEList.  (But leave references to the ROWID column 
-** unchanged.)
-**
-** This routine is part of the flattening procedure.  A subquery
-** whose result set is defined by pEList appears as entry in the
-** FROM clause of a SELECT such that the VDBE cursor assigned to that
-** FORM clause entry is iTable.  This routine make the necessary 
-** changes to pExpr so that it refers directly to the source table
-** of the subquery rather the result set of the subquery.
+** Table p is a virtual table. This function moves all elements in the
+** p->pVTable list to the sqlite3.pDisconnect lists of their associated
+** database connections to be disconnected at the next opportunity. 
+** Except, if argument db is not NULL, then the entry associated with
+** connection db is left in the p->pVTable list.
 */
-static void substExpr(
-  sqlite3 *db,        /* Report malloc errors to this connection */
-  Expr *pExpr,        /* Expr in which substitution occurs */
-  int iTable,         /* Table to be substituted */
-  ExprList *pEList    /* Substitute expressions */
-){
-  if( pExpr==0 ) return;
-  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
-    if( pExpr->iColumn<0 ){
-      pExpr->op = TK_NULL;
+static VTable *vtabDisconnectAll(sqlite3 *db, Table *p){
+  VTable *pRet = 0;
+  VTable *pVTable = p->pVTable;
+  p->pVTable = 0;
+
+  /* Assert that the mutex (if any) associated with the BtShared database 
+  ** that contains table p is held by the caller. See header comments 
+  ** above function sqlite3VtabUnlockList() for an explanation of why
+  ** this makes it safe to access the sqlite3.pDisconnect list of any
+  ** database connection that may have an entry in the p->pVTable list.  */
+  assert( db==0 ||
+    sqlite3BtreeHoldsMutex(db->aDb[sqlite3SchemaToIndex(db, p->pSchema)].pBt) 
+  );
+
+  while( pVTable ){
+    sqlite3 *db2 = pVTable->db;
+    VTable *pNext = pVTable->pNext;
+    assert( db2 );
+    if( db2==db ){
+      pRet = pVTable;
+      p->pVTable = pRet;
+      pRet->pNext = 0;
     }else{
-      Expr *pNew;
-      assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
-      assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
-      pNew = pEList->a[pExpr->iColumn].pExpr;
-      assert( pNew!=0 );
-      pExpr->op = pNew->op;
-      assert( pExpr->pLeft==0 );
-      pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft);
-      assert( pExpr->pRight==0 );
-      pExpr->pRight = sqlite3ExprDup(db, pNew->pRight);
-      assert( pExpr->pList==0 );
-      pExpr->pList = sqlite3ExprListDup(db, pNew->pList);
-      pExpr->iTable = pNew->iTable;
-      pExpr->pTab = pNew->pTab;
-      pExpr->iColumn = pNew->iColumn;
-      pExpr->iAgg = pNew->iAgg;
-      sqlite3TokenCopy(db, &pExpr->token, &pNew->token);
-      sqlite3TokenCopy(db, &pExpr->span, &pNew->span);
-      pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect);
-      pExpr->flags = pNew->flags;
+      pVTable->pNext = db2->pDisconnect;
+      db2->pDisconnect = pVTable;
     }
-  }else{
-    substExpr(db, pExpr->pLeft, iTable, pEList);
-    substExpr(db, pExpr->pRight, iTable, pEList);
-    substSelect(db, pExpr->pSelect, iTable, pEList);
-    substExprList(db, pExpr->pList, iTable, pEList);
-  }
-}
-static void substExprList(
-  sqlite3 *db,         /* Report malloc errors here */
-  ExprList *pList,     /* List to scan and in which to make substitutes */
-  int iTable,          /* Table to be substituted */
-  ExprList *pEList     /* Substitute values */
-){
-  int i;
-  if( pList==0 ) return;
-  for(i=0; i<pList->nExpr; i++){
-    substExpr(db, pList->a[i].pExpr, iTable, pEList);
+    pVTable = pNext;
   }
+
+  assert( !db || pRet );
+  return pRet;
 }
-static void substSelect(
-  sqlite3 *db,         /* Report malloc errors here */
-  Select *p,           /* SELECT statement in which to make substitutions */
-  int iTable,          /* Table to be replaced */
-  ExprList *pEList     /* Substitute values */
-){
-  if( !p ) return;
-  substExprList(db, p->pEList, iTable, pEList);
-  substExprList(db, p->pGroupBy, iTable, pEList);
-  substExprList(db, p->pOrderBy, iTable, pEList);
-  substExpr(db, p->pHaving, iTable, pEList);
-  substExpr(db, p->pWhere, iTable, pEList);
-  substSelect(db, p->pPrior, iTable, pEList);
-}
-#endif /* !defined(SQLITE_OMIT_VIEW) */
 
-#ifndef SQLITE_OMIT_VIEW
+
 /*
-** This routine attempts to flatten subqueries in order to speed
-** execution.  It returns 1 if it makes changes and 0 if no flattening
-** occurs.
-**
-** To understand the concept of flattening, consider the following
-** query:
-**
-**     SELECT a FROM (SELECT x+y AS a FROM t1 WHERE z<100) WHERE a>5
-**
-** The default way of implementing this query is to execute the
-** subquery first and store the results in a temporary table, then
-** run the outer query on that temporary table.  This requires two
-** passes over the data.  Furthermore, because the temporary table
-** has no indices, the WHERE clause on the outer query cannot be
-** optimized.
-**
-** This routine attempts to rewrite queries such as the above into
-** a single flat select, like this:
-**
-**     SELECT x+y AS a FROM t1 WHERE z<100 AND a>5
-**
-** The code generated for this simpification gives the same result
-** but only has to scan the data once.  And because indices might 
-** exist on the table t1, a complete scan of the data might be
-** avoided.
-**
-** Flattening is only attempted if all of the following are true:
-**
-**   (1)  The subquery and the outer query do not both use aggregates.
+** Disconnect all the virtual table objects in the sqlite3.pDisconnect list.
 **
-**   (2)  The subquery is not an aggregate or the outer query is not a join.
-**
-**   (3)  The subquery is not the right operand of a left outer join, or
-**        the subquery is not itself a join.  (Ticket #306)
-**
-**   (4)  The subquery is not DISTINCT or the outer query is not a join.
-**
-**   (5)  The subquery is not DISTINCT or the outer query does not use
-**        aggregates.
-**
-**   (6)  The subquery does not use aggregates or the outer query is not
-**        DISTINCT.
-**
-**   (7)  The subquery has a FROM clause.
-**
-**   (8)  The subquery does not use LIMIT or the outer query is not a join.
-**
-**   (9)  The subquery does not use LIMIT or the outer query does not use
-**        aggregates.
-**
-**  (10)  The subquery does not use aggregates or the outer query does not
-**        use LIMIT.
-**
-**  (11)  The subquery and the outer query do not both have ORDER BY clauses.
-**
-**  (12)  The subquery is not the right term of a LEFT OUTER JOIN or the
-**        subquery has no WHERE clause.  (added by ticket #350)
-**
-**  (13)  The subquery and outer query do not both use LIMIT
-**
-**  (14)  The subquery does not use OFFSET
-**
-**  (15)  The outer query is not part of a compound select or the
-**        subquery does not have both an ORDER BY and a LIMIT clause.
-**        (See ticket #2339)
-**
-**  (16)  The outer query is not an aggregate or the subquery does
-**        not contain ORDER BY.  (Ticket #2942)  This used to not matter
-**        until we introduced the group_concat() function.  
+** This function may only be called when the mutexes associated with all
+** shared b-tree databases opened using connection db are held by the 
+** caller. This is done to protect the sqlite3.pDisconnect list. The
+** sqlite3.pDisconnect list is accessed only as follows:
 **
-** In this routine, the "p" parameter is a pointer to the outer query.
-** The subquery is p->pSrc->a[iFrom].  isAgg is true if the outer query
-** uses aggregates and subqueryIsAgg is true if the subquery uses aggregates.
+**   1) By this function. In this case, all BtShared mutexes and the mutex
+**      associated with the database handle itself must be held.
 **
-** If flattening is not attempted, this routine is a no-op and returns 0.
-** If flattening is attempted this routine returns 1.
+**   2) By function vtabDisconnectAll(), when it adds a VTable entry to
+**      the sqlite3.pDisconnect list. In this case either the BtShared mutex
+**      associated with the database the virtual table is stored in is held
+**      or, if the virtual table is stored in a non-sharable database, then
+**      the database handle mutex is held.
 **
-** All of the expression analysis must occur on both the outer query and
-** the subquery before this routine runs.
+** As a result, a sqlite3.pDisconnect cannot be accessed simultaneously 
+** by multiple threads. It is thread-safe.
 */
-static int flattenSubquery(
-  sqlite3 *db,         /* Database connection */
-  Select *p,           /* The parent or outer SELECT statement */
-  int iFrom,           /* Index in p->pSrc->a[] of the inner subquery */
-  int isAgg,           /* True if outer SELECT uses aggregate functions */
-  int subqueryIsAgg    /* True if the subquery uses aggregate functions */
-){
-  Select *pSub;       /* The inner query or "subquery" */
-  SrcList *pSrc;      /* The FROM clause of the outer query */
-  SrcList *pSubSrc;   /* The FROM clause of the subquery */
-  ExprList *pList;    /* The result set of the outer query */
-  int iParent;        /* VDBE cursor number of the pSub result set temp table */
-  int i;              /* Loop counter */
-  Expr *pWhere;                    /* The WHERE clause */
-  struct SrcList_item *pSubitem;   /* The subquery */
+SQLITE_PRIVATE void sqlite3VtabUnlockList(sqlite3 *db){
+  VTable *p = db->pDisconnect;
+  db->pDisconnect = 0;
 
-  /* Check to see if flattening is permitted.  Return 0 if not.
-  */
-  if( p==0 ) return 0;
-  pSrc = p->pSrc;
-  assert( pSrc && iFrom>=0 && iFrom<pSrc->nSrc );
-  pSubitem = &pSrc->a[iFrom];
-  pSub = pSubitem->pSelect;
-  assert( pSub!=0 );
-  if( isAgg && subqueryIsAgg ) return 0;                 /* Restriction (1)  */
-  if( subqueryIsAgg && pSrc->nSrc>1 ) return 0;          /* Restriction (2)  */
-  pSubSrc = pSub->pSrc;
-  assert( pSubSrc );
-  /* Prior to version 3.1.2, when LIMIT and OFFSET had to be simple constants,
-  ** not arbitrary expresssions, we allowed some combining of LIMIT and OFFSET
-  ** because they could be computed at compile-time.  But when LIMIT and OFFSET
-  ** became arbitrary expressions, we were forced to add restrictions (13)
-  ** and (14). */
-  if( pSub->pLimit && p->pLimit ) return 0;              /* Restriction (13) */
-  if( pSub->pOffset ) return 0;                          /* Restriction (14) */
-  if( p->pRightmost && pSub->pLimit && pSub->pOrderBy ){
-    return 0;                                            /* Restriction (15) */
+  assert( sqlite3BtreeHoldsAllMutexes(db) );
+  assert( sqlite3_mutex_held(db->mutex) );
+
+  if( p ){
+    sqlite3ExpirePreparedStatements(db);
+    do {
+      VTable *pNext = p->pNext;
+      sqlite3VtabUnlock(p);
+      p = pNext;
+    }while( p );
   }
-  if( pSubSrc->nSrc==0 ) return 0;                       /* Restriction (7)  */
-  if( (pSub->isDistinct || pSub->pLimit) 
-         && (pSrc->nSrc>1 || isAgg) ){          /* Restrictions (4)(5)(8)(9) */
-     return 0;       
+}
+
+/*
+** Clear any and all virtual-table information from the Table record.
+** This routine is called, for example, just before deleting the Table
+** record.
+**
+** Since it is a virtual-table, the Table structure contains a pointer
+** to the head of a linked list of VTable structures. Each VTable 
+** structure is associated with a single sqlite3* user of the schema.
+** The reference count of the VTable structure associated with database 
+** connection db is decremented immediately (which may lead to the 
+** structure being xDisconnected and free). Any other VTable structures
+** in the list are moved to the sqlite3.pDisconnect list of the associated 
+** database connection.
+*/
+SQLITE_PRIVATE void sqlite3VtabClear(Table *p){
+  vtabDisconnectAll(0, p);
+  if( p->azModuleArg ){
+    int i;
+    for(i=0; i<p->nModuleArg; i++){
+      sqlite3DbFree(p->dbMem, p->azModuleArg[i]);
+    }
+    sqlite3DbFree(p->dbMem, p->azModuleArg);
   }
-  if( p->isDistinct && subqueryIsAgg ) return 0;         /* Restriction (6)  */
-  if( (p->disallowOrderBy || p->pOrderBy) && pSub->pOrderBy ){
-     return 0;                                           /* Restriction (11) */
+}
+
+/*
+** Add a new module argument to pTable->azModuleArg[].
+** The string is not copied - the pointer is stored.  The
+** string will be freed automatically when the table is
+** deleted.
+*/
+static void addModuleArgument(sqlite3 *db, Table *pTable, char *zArg){
+  int i = pTable->nModuleArg++;
+  int nBytes = sizeof(char *)*(1+pTable->nModuleArg);
+  char **azModuleArg;
+  azModuleArg = sqlite3DbRealloc(db, pTable->azModuleArg, nBytes);
+  if( azModuleArg==0 ){
+    int j;
+    for(j=0; j<i; j++){
+      sqlite3DbFree(db, pTable->azModuleArg[j]);
+    }
+    sqlite3DbFree(db, zArg);
+    sqlite3DbFree(db, pTable->azModuleArg);
+    pTable->nModuleArg = 0;
+  }else{
+    azModuleArg[i] = zArg;
+    azModuleArg[i+1] = 0;
   }
-  if( isAgg && pSub->pOrderBy ) return 0;                /* Restriction (16) */
+  pTable->azModuleArg = azModuleArg;
+}
 
-  /* Restriction 3:  If the subquery is a join, make sure the subquery is 
-  ** not used as the right operand of an outer join.  Examples of why this
-  ** is not allowed:
-  **
-  **         t1 LEFT OUTER JOIN (t2 JOIN t3)
-  **
-  ** If we flatten the above, we would get
-  **
-  **         (t1 LEFT OUTER JOIN t2) JOIN t3
-  **
-  ** which is not at all the same thing.
+/*
+** The parser calls this routine when it first sees a CREATE VIRTUAL TABLE
+** statement.  The module name has been parsed, but the optional list
+** of parameters that follow the module name are still pending.
+*/
+SQLITE_PRIVATE void sqlite3VtabBeginParse(
+  Parse *pParse,        /* Parsing context */
+  Token *pName1,        /* Name of new table, or database name */
+  Token *pName2,        /* Name of new table or NULL */
+  Token *pModuleName    /* Name of the module for the virtual table */
+){
+  int iDb;              /* The database the table is being created in */
+  Table *pTable;        /* The new virtual table */
+  sqlite3 *db;          /* Database connection */
+
+  sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, 0);
+  pTable = pParse->pNewTable;
+  if( pTable==0 ) return;
+  assert( 0==pTable->pIndex );
+
+  db = pParse->db;
+  iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
+  assert( iDb>=0 );
+
+  pTable->tabFlags |= TF_Virtual;
+  pTable->nModuleArg = 0;
+  addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
+  addModuleArgument(db, pTable, sqlite3DbStrDup(db, db->aDb[iDb].zName));
+  addModuleArgument(db, pTable, sqlite3DbStrDup(db, pTable->zName));
+  pParse->sNameToken.n = (int)(&pModuleName->z[pModuleName->n] - pName1->z);
+
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  /* Creating a virtual table invokes the authorization callback twice.
+  ** The first invocation, to obtain permission to INSERT a row into the
+  ** sqlite_master table, has already been made by sqlite3StartTable().
+  ** The second call, to obtain permission to create the table, is made now.
   */
-  if( pSubSrc->nSrc>1 && (pSubitem->jointype & JT_OUTER)!=0 ){
-    return 0;
+  if( pTable->azModuleArg ){
+    sqlite3AuthCheck(pParse, SQLITE_CREATE_VTABLE, pTable->zName, 
+            pTable->azModuleArg[0], pParse->db->aDb[iDb].zName);
   }
+#endif
+}
 
-  /* Restriction 12:  If the subquery is the right operand of a left outer
-  ** join, make sure the subquery has no WHERE clause.
-  ** An examples of why this is not allowed:
-  **
-  **         t1 LEFT OUTER JOIN (SELECT * FROM t2 WHERE t2.x>0)
-  **
-  ** If we flatten the above, we would get
-  **
-  **         (t1 LEFT OUTER JOIN t2) WHERE t2.x>0
-  **
-  ** But the t2.x>0 test will always fail on a NULL row of t2, which
-  ** effectively converts the OUTER JOIN into an INNER JOIN.
-  */
-  if( (pSubitem->jointype & JT_OUTER)!=0 && pSub->pWhere!=0 ){
-    return 0;
+/*
+** This routine takes the module argument that has been accumulating
+** in pParse->zArg[] and appends it to the list of arguments on the
+** virtual table currently under construction in pParse->pTable.
+*/
+static void addArgumentToVtab(Parse *pParse){
+  if( pParse->sArg.z && ALWAYS(pParse->pNewTable) ){
+    const char *z = (const char*)pParse->sArg.z;
+    int n = pParse->sArg.n;
+    sqlite3 *db = pParse->db;
+    addModuleArgument(db, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
   }
+}
 
-  /* If we reach this point, it means flattening is permitted for the
-  ** iFrom-th entry of the FROM clause in the outer query.
-  */
+/*
+** The parser calls this routine after the CREATE VIRTUAL TABLE statement
+** has been completely parsed.
+*/
+SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
+  Table *pTab = pParse->pNewTable;  /* The table being constructed */
+  sqlite3 *db = pParse->db;         /* The database connection */
 
-  /* Move all of the FROM elements of the subquery into the
-  ** the FROM clause of the outer query.  Before doing this, remember
-  ** the cursor number for the original outer query FROM element in
-  ** iParent.  The iParent cursor will never be used.  Subsequent code
-  ** will scan expressions looking for iParent references and replace
-  ** those references with expressions that resolve to the subquery FROM
-  ** elements we are now copying in.
+  if( pTab==0 ) return;
+  addArgumentToVtab(pParse);
+  pParse->sArg.z = 0;
+  if( pTab->nModuleArg<1 ) return;
+  
+  /* If the CREATE VIRTUAL TABLE statement is being entered for the
+  ** first time (in other words if the virtual table is actually being
+  ** created now instead of just being read out of sqlite_master) then
+  ** do additional initialization work and store the statement text
+  ** in the sqlite_master table.
   */
-  iParent = pSubitem->iCursor;
-  {
-    int nSubSrc = pSubSrc->nSrc;
-    int jointype = pSubitem->jointype;
+  if( !db->init.busy ){
+    char *zStmt;
+    char *zWhere;
+    int iDb;
+    Vdbe *v;
 
-    sqlite3DeleteTable(pSubitem->pTab);
-    sqlite3_free(pSubitem->zDatabase);
-    sqlite3_free(pSubitem->zName);
-    sqlite3_free(pSubitem->zAlias);
-    pSubitem->pTab = 0;
-    pSubitem->zDatabase = 0;
-    pSubitem->zName = 0;
-    pSubitem->zAlias = 0;
-    if( nSubSrc>1 ){
-      int extra = nSubSrc - 1;
-      for(i=1; i<nSubSrc; i++){
-        pSrc = sqlite3SrcListAppend(db, pSrc, 0, 0);
-        if( pSrc==0 ){
-          p->pSrc = 0;
-          return 1;
-        }
-      }
-      p->pSrc = pSrc;
-      for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){
-        pSrc->a[i] = pSrc->a[i-extra];
-      }
-    }
-    for(i=0; i<nSubSrc; i++){
-      pSrc->a[i+iFrom] = pSubSrc->a[i];
-      memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i]));
+    /* Compute the complete text of the CREATE VIRTUAL TABLE statement */
+    if( pEnd ){
+      pParse->sNameToken.n = (int)(pEnd->z - pParse->sNameToken.z) + pEnd->n;
     }
-    pSrc->a[iFrom].jointype = jointype;
-  }
+    zStmt = sqlite3MPrintf(db, "CREATE VIRTUAL TABLE %T", &pParse->sNameToken);
 
-  /* Now begin substituting subquery result set expressions for 
-  ** references to the iParent in the outer query.
-  ** 
-  ** Example:
-  **
-  **   SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b;
-  **   \                     \_____________ subquery __________/          /
-  **    \_____________________ outer query ______________________________/
-  **
-  ** We look at every expression in the outer query and every place we see
-  ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
-  */
-  pList = p->pEList;
-  for(i=0; i<pList->nExpr; i++){
-    Expr *pExpr;
-    if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){
-      pList->a[i].zName = 
-             sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n);
-    }
-  }
-  substExprList(db, p->pEList, iParent, pSub->pEList);
-  if( isAgg ){
-    substExprList(db, p->pGroupBy, iParent, pSub->pEList);
-    substExpr(db, p->pHaving, iParent, pSub->pEList);
-  }
-  if( pSub->pOrderBy ){
-    assert( p->pOrderBy==0 );
-    p->pOrderBy = pSub->pOrderBy;
-    pSub->pOrderBy = 0;
-  }else if( p->pOrderBy ){
-    substExprList(db, p->pOrderBy, iParent, pSub->pEList);
-  }
-  if( pSub->pWhere ){
-    pWhere = sqlite3ExprDup(db, pSub->pWhere);
-  }else{
-    pWhere = 0;
+    /* A slot for the record has already been allocated in the 
+    ** SQLITE_MASTER table.  We just need to update that slot with all
+    ** the information we've collected.  
+    **
+    ** The VM register number pParse->regRowid holds the rowid of an
+    ** entry in the sqlite_master table tht was created for this vtab
+    ** by sqlite3StartTable().
+    */
+    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    sqlite3NestedParse(pParse,
+      "UPDATE %Q.%s "
+         "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
+       "WHERE rowid=#%d",
+      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
+      pTab->zName,
+      pTab->zName,
+      zStmt,
+      pParse->regRowid
+    );
+    sqlite3DbFree(db, zStmt);
+    v = sqlite3GetVdbe(pParse);
+    sqlite3ChangeCookie(pParse, iDb);
+
+    sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
+    zWhere = sqlite3MPrintf(db, "name='%q'", pTab->zName);
+    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 1, 0, zWhere, P4_DYNAMIC);
+    sqlite3VdbeAddOp4(v, OP_VCreate, iDb, 0, 0, 
+                         pTab->zName, sqlite3Strlen30(pTab->zName) + 1);
   }
-  if( subqueryIsAgg ){
-    assert( p->pHaving==0 );
-    p->pHaving = p->pWhere;
-    p->pWhere = pWhere;
-    substExpr(db, p->pHaving, iParent, pSub->pEList);
-    p->pHaving = sqlite3ExprAnd(db, p->pHaving, 
-                                sqlite3ExprDup(db, pSub->pHaving));
-    assert( p->pGroupBy==0 );
-    p->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy);
-  }else{
-    substExpr(db, p->pWhere, iParent, pSub->pEList);
-    p->pWhere = sqlite3ExprAnd(db, p->pWhere, pWhere);
+
+  /* If we are rereading the sqlite_master table create the in-memory
+  ** record of the table. The xConnect() method is not called until
+  ** the first time the virtual table is used in an SQL statement. This
+  ** allows a schema that contains virtual tables to be loaded before
+  ** the required virtual table implementations are registered.  */
+  else {
+    Table *pOld;
+    Schema *pSchema = pTab->pSchema;
+    const char *zName = pTab->zName;
+    int nName = sqlite3Strlen30(zName);
+    pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
+    if( pOld ){
+      db->mallocFailed = 1;
+      assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
+      return;
+    }
+    pSchema->db = pParse->db;
+    pParse->pNewTable = 0;
   }
+}
 
-  /* The flattened query is distinct if either the inner or the
-  ** outer query is distinct. 
-  */
-  p->isDistinct = p->isDistinct || pSub->isDistinct;
+/*
+** The parser calls this routine when it sees the first token
+** of an argument to the module name in a CREATE VIRTUAL TABLE statement.
+*/
+SQLITE_PRIVATE void sqlite3VtabArgInit(Parse *pParse){
+  addArgumentToVtab(pParse);
+  pParse->sArg.z = 0;
+  pParse->sArg.n = 0;
+}
 
-  /*
-  ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y;
-  **
-  ** One is tempted to try to add a and b to combine the limits.  But this
-  ** does not work if either limit is negative.
-  */
-  if( pSub->pLimit ){
-    p->pLimit = pSub->pLimit;
-    pSub->pLimit = 0;
+/*
+** The parser calls this routine for each token after the first token
+** in an argument to the module name in a CREATE VIRTUAL TABLE statement.
+*/
+SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse *pParse, Token *p){
+  Token *pArg = &pParse->sArg;
+  if( pArg->z==0 ){
+    pArg->z = p->z;
+    pArg->n = p->n;
+  }else{
+    assert(pArg->z < p->z);
+    pArg->n = (int)(&p->z[p->n] - pArg->z);
   }
-
-  /* Finially, delete what is left of the subquery and return
-  ** success.
-  */
-  sqlite3SelectDelete(pSub);
-  return 1;
 }
-#endif /* SQLITE_OMIT_VIEW */
 
 /*
-** Analyze the SELECT statement passed as an argument to see if it
-** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if 
-** it is, or 0 otherwise. At present, a query is considered to be
-** a min()/max() query if:
-**
-**   1. There is a single object in the FROM clause.
-**
-**   2. There is a single expression in the result set, and it is
-**      either min(x) or max(x), where x is a column reference.
+** Invoke a virtual table constructor (either xCreate or xConnect). The
+** pointer to the function to invoke is passed as the fourth parameter
+** to this procedure.
 */
-static int minMaxQuery(Parse *pParse, Select *p){
-  Expr *pExpr;
-  ExprList *pEList = p->pEList;
+static int vtabCallConstructor(
+  sqlite3 *db, 
+  Table *pTab,
+  Module *pMod,
+  int (*xConstruct)(sqlite3*,void*,int,const char*const*,sqlite3_vtab**,char**),
+  char **pzErr
+){
+  VTable *pVTable;
+  int rc;
+  const char *const*azArg = (const char *const*)pTab->azModuleArg;
+  int nArg = pTab->nModuleArg;
+  char *zErr = 0;
+  char *zModuleName = sqlite3MPrintf(db, "%s", pTab->zName);
 
-  if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
-  pExpr = pEList->a[0].pExpr;
-  pEList = pExpr->pList;
-  if( pExpr->op!=TK_AGG_FUNCTION || pEList==0 || pEList->nExpr!=1 ) return 0;
-  if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
-  if( pExpr->token.n!=3 ) return WHERE_ORDERBY_NORMAL;
-  if( sqlite3StrNICmp((char*)pExpr->token.z,"min",3)==0 ){
-    return WHERE_ORDERBY_MIN;
-  }else if( sqlite3StrNICmp((char*)pExpr->token.z,"max",3)==0 ){
-    return WHERE_ORDERBY_MAX;
+  if( !zModuleName ){
+    return SQLITE_NOMEM;
+  }
+
+  pVTable = sqlite3DbMallocZero(db, sizeof(VTable));
+  if( !pVTable ){
+    sqlite3DbFree(db, zModuleName);
+    return SQLITE_NOMEM;
+  }
+  pVTable->db = db;
+  pVTable->pMod = pMod;
+
+  assert( !db->pVTab );
+  assert( xConstruct );
+  db->pVTab = pTab;
+
+  /* Invoke the virtual table constructor */
+  (void)sqlite3SafetyOff(db);
+  rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
+  (void)sqlite3SafetyOn(db);
+  if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
+
+  if( SQLITE_OK!=rc ){
+    if( zErr==0 ){
+      *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
+    }else {
+      *pzErr = sqlite3MPrintf(db, "%s", zErr);
+      sqlite3DbFree(db, zErr);
+    }
+    sqlite3DbFree(db, pVTable);
+  }else if( ALWAYS(pVTable->pVtab) ){
+    /* Justification of ALWAYS():  A correct vtab constructor must allocate
+    ** the sqlite3_vtab object if successful.  */
+    pVTable->pVtab->pModule = pMod->pModule;
+    pVTable->nRef = 1;
+    if( db->pVTab ){
+      const char *zFormat = "vtable constructor did not declare schema: %s";
+      *pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
+      sqlite3VtabUnlock(pVTable);
+      rc = SQLITE_ERROR;
+    }else{
+      int iCol;
+      /* If everything went according to plan, link the new VTable structure
+      ** into the linked list headed by pTab->pVTable. Then loop through the 
+      ** columns of the table to see if any of them contain the token "hidden".
+      ** If so, set the Column.isHidden flag and remove the token from
+      ** the type string.  */
+      pVTable->pNext = pTab->pVTable;
+      pTab->pVTable = pVTable;
+
+      for(iCol=0; iCol<pTab->nCol; iCol++){
+        char *zType = pTab->aCol[iCol].zType;
+        int nType;
+        int i = 0;
+        if( !zType ) continue;
+        nType = sqlite3Strlen30(zType);
+        if( sqlite3StrNICmp("hidden", zType, 6)||(zType[6] && zType[6]!=' ') ){
+          for(i=0; i<nType; i++){
+            if( (0==sqlite3StrNICmp(" hidden", &zType[i], 7))
+             && (zType[i+7]=='\0' || zType[i+7]==' ')
+            ){
+              i++;
+              break;
+            }
+          }
+        }
+        if( i<nType ){
+          int j;
+          int nDel = 6 + (zType[i+6] ? 1 : 0);
+          for(j=i; (j+nDel)<=nType; j++){
+            zType[j] = zType[j+nDel];
+          }
+          if( zType[i]=='\0' && i>0 ){
+            assert(zType[i-1]==' ');
+            zType[i-1] = '\0';
+          }
+          pTab->aCol[iCol].isHidden = 1;
+        }
+      }
+    }
   }
-  return WHERE_ORDERBY_NORMAL;
+
+  sqlite3DbFree(db, zModuleName);
+  db->pVTab = 0;
+  return rc;
 }
 
 /*
-** This routine resolves any names used in the result set of the
-** supplied SELECT statement. If the SELECT statement being resolved
-** is a sub-select, then pOuterNC is a pointer to the NameContext 
-** of the parent SELECT.
+** This function is invoked by the parser to call the xConnect() method
+** of the virtual table pTab. If an error occurs, an error code is returned 
+** and an error left in pParse.
+**
+** This call is a no-op if table pTab is not a virtual table.
 */
-SQLITE_PRIVATE int sqlite3SelectResolve(
-  Parse *pParse,         /* The parser context */
-  Select *p,             /* The SELECT statement being coded. */
-  NameContext *pOuterNC  /* The outer name context. May be NULL. */
-){
-  ExprList *pEList;          /* Result set. */
-  int i;                     /* For-loop variable used in multiple places */
-  NameContext sNC;           /* Local name-context */
-  ExprList *pGroupBy;        /* The group by clause */
-
-  /* If this routine has run before, return immediately. */
-  if( p->isResolved ){
-    assert( !pOuterNC );
+SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
+  sqlite3 *db = pParse->db;
+  const char *zMod;
+  Module *pMod;
+  int rc;
+
+  assert( pTab );
+  if( (pTab->tabFlags & TF_Virtual)==0 || sqlite3GetVTable(db, pTab) ){
     return SQLITE_OK;
   }
-  p->isResolved = 1;
 
-  /* If there have already been errors, do nothing. */
-  if( pParse->nErr>0 ){
-    return SQLITE_ERROR;
-  }
+  /* Locate the required virtual table module */
+  zMod = pTab->azModuleArg[0];
+  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod, sqlite3Strlen30(zMod));
 
-  /* Prepare the select statement. This call will allocate all cursors
-  ** required to handle the tables and subqueries in the FROM clause.
-  */
-  if( prepSelectStmt(pParse, p) ){
-    return SQLITE_ERROR;
+  if( !pMod ){
+    const char *zModule = pTab->azModuleArg[0];
+    sqlite3ErrorMsg(pParse, "no such module: %s", zModule);
+    rc = SQLITE_ERROR;
+  }else{
+    char *zErr = 0;
+    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xConnect, &zErr);
+    if( rc!=SQLITE_OK ){
+      sqlite3ErrorMsg(pParse, "%s", zErr);
+    }
+    sqlite3DbFree(db, zErr);
   }
 
-  /* Resolve the expressions in the LIMIT and OFFSET clauses. These
-  ** are not allowed to refer to any names, so pass an empty NameContext.
-  */
-  memset(&sNC, 0, sizeof(sNC));
-  sNC.pParse = pParse;
-  if( sqlite3ExprResolveNames(&sNC, p->pLimit) ||
-      sqlite3ExprResolveNames(&sNC, p->pOffset) ){
-    return SQLITE_ERROR;
-  }
+  return rc;
+}
 
-  /* Set up the local name-context to pass to ExprResolveNames() to
-  ** resolve the expression-list.
-  */
-  sNC.allowAgg = 1;
-  sNC.pSrcList = p->pSrc;
-  sNC.pNext = pOuterNC;
+/*
+** Add the virtual table pVTab to the array sqlite3.aVTrans[].
+*/
+static int addToVTrans(sqlite3 *db, VTable *pVTab){
+  const int ARRAY_INCR = 5;
 
-  /* Resolve names in the result set. */
-  pEList = p->pEList;
-  if( !pEList ) return SQLITE_ERROR;
-  for(i=0; i<pEList->nExpr; i++){
-    Expr *pX = pEList->a[i].pExpr;
-    if( sqlite3ExprResolveNames(&sNC, pX) ){
-      return SQLITE_ERROR;
+  /* Grow the sqlite3.aVTrans array if required */
+  if( (db->nVTrans%ARRAY_INCR)==0 ){
+    VTable **aVTrans;
+    int nBytes = sizeof(sqlite3_vtab *) * (db->nVTrans + ARRAY_INCR);
+    aVTrans = sqlite3DbRealloc(db, (void *)db->aVTrans, nBytes);
+    if( !aVTrans ){
+      return SQLITE_NOMEM;
     }
+    memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
+    db->aVTrans = aVTrans;
   }
 
-  /* If there are no aggregate functions in the result-set, and no GROUP BY 
-  ** expression, do not allow aggregates in any of the other expressions.
+  /* Add pVtab to the end of sqlite3.aVTrans */
+  db->aVTrans[db->nVTrans++] = pVTab;
+  sqlite3VtabLock(pVTab);
+  return SQLITE_OK;
+}
+
+/*
+** This function is invoked by the vdbe to call the xCreate method
+** of the virtual table named zTab in database iDb. 
+**
+** If an error occurs, *pzErr is set to point an an English language
+** description of the error and an SQLITE_XXX error code is returned.
+** In this case the caller must call sqlite3DbFree(db, ) on *pzErr.
+*/
+SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
+  int rc = SQLITE_OK;
+  Table *pTab;
+  Module *pMod;
+  const char *zMod;
+
+  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
+  assert( pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVTable );
+
+  /* Locate the required virtual table module */
+  zMod = pTab->azModuleArg[0];
+  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod, sqlite3Strlen30(zMod));
+
+  /* If the module has been registered and includes a Create method, 
+  ** invoke it now. If the module has not been registered, return an 
+  ** error. Otherwise, do nothing.
   */
-  assert( !p->isAgg );
-  pGroupBy = p->pGroupBy;
-  if( pGroupBy || sNC.hasAgg ){
-    p->isAgg = 1;
+  if( !pMod ){
+    *pzErr = sqlite3MPrintf(db, "no such module: %s", zMod);
+    rc = SQLITE_ERROR;
   }else{
-    sNC.allowAgg = 0;
+    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xCreate, pzErr);
   }
 
-  /* If a HAVING clause is present, then there must be a GROUP BY clause.
-  */
-  if( p->pHaving && !pGroupBy ){
-    sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
-    return SQLITE_ERROR;
+  /* Justification of ALWAYS():  The xConstructor method is required to
+  ** create a valid sqlite3_vtab if it returns SQLITE_OK. */
+  if( rc==SQLITE_OK && ALWAYS(sqlite3GetVTable(db, pTab)) ){
+      rc = addToVTrans(db, sqlite3GetVTable(db, pTab));
   }
 
-  /* Add the expression list to the name-context before parsing the
-  ** other expressions in the SELECT statement. This is so that
-  ** expressions in the WHERE clause (etc.) can refer to expressions by
-  ** aliases in the result set.
-  **
-  ** Minor point: If this is the case, then the expression will be
-  ** re-evaluated for each reference to it.
-  */
-  sNC.pEList = p->pEList;
-  if( sqlite3ExprResolveNames(&sNC, p->pWhere) ||
-     sqlite3ExprResolveNames(&sNC, p->pHaving) ){
-    return SQLITE_ERROR;
-  }
-  if( p->pPrior==0 ){
-    if( processOrderGroupBy(pParse, p, p->pOrderBy, 1, &sNC.hasAgg) ){
-      return SQLITE_ERROR;
-    }
-  }
-  if( processOrderGroupBy(pParse, p, pGroupBy, 0, &sNC.hasAgg) ){
-    return SQLITE_ERROR;
-  }
+  return rc;
+}
 
-  if( pParse->db->mallocFailed ){
-    return SQLITE_NOMEM;
+/*
+** This function is used to set the schema of a virtual table.  It is only
+** valid to call this function from within the xCreate() or xConnect() of a
+** virtual table module.
+*/
+SQLITE_API int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
+  Parse *pParse;
+
+  int rc = SQLITE_OK;
+  Table *pTab;
+  char *zErr = 0;
+
+  sqlite3_mutex_enter(db->mutex);
+  pTab = db->pVTab;
+  if( !pTab ){
+    sqlite3Error(db, SQLITE_MISUSE, 0);
+    sqlite3_mutex_leave(db->mutex);
+    return SQLITE_MISUSE;
   }
+  assert( (pTab->tabFlags & TF_Virtual)!=0 );
 
-  /* Make sure the GROUP BY clause does not contain aggregate functions.
-  */
-  if( pGroupBy ){
-    struct ExprList_item *pItem;
+  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
+  if( pParse==0 ){
+    rc = SQLITE_NOMEM;
+  }else{
+    pParse->declareVtab = 1;
+    pParse->db = db;
   
-    for(i=0, pItem=pGroupBy->a; i<pGroupBy->nExpr; i++, pItem++){
-      if( ExprHasProperty(pItem->pExpr, EP_Agg) ){
-        sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
-            "the GROUP BY clause");
-        return SQLITE_ERROR;
+    if( 
+        SQLITE_OK == sqlite3RunParser(pParse, zCreateTable, &zErr) && 
+        pParse->pNewTable && 
+        !pParse->pNewTable->pSelect && 
+        (pParse->pNewTable->tabFlags & TF_Virtual)==0
+    ){
+      if( !pTab->aCol ){
+        pTab->aCol = pParse->pNewTable->aCol;
+        pTab->nCol = pParse->pNewTable->nCol;
+        pParse->pNewTable->nCol = 0;
+        pParse->pNewTable->aCol = 0;
       }
+      db->pVTab = 0;
+    } else {
+      sqlite3Error(db, SQLITE_ERROR, zErr);
+      sqlite3DbFree(db, zErr);
+      rc = SQLITE_ERROR;
+    }
+    pParse->declareVtab = 0;
+  
+    if( pParse->pVdbe ){
+      sqlite3VdbeFinalize(pParse->pVdbe);
     }
+    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3StackFree(db, pParse);
   }
 
-  /* If this is one SELECT of a compound, be sure to resolve names
-  ** in the other SELECTs.
-  */
-  if( p->pPrior ){
-    return sqlite3SelectResolve(pParse, p->pPrior, pOuterNC);
-  }else{
-    return SQLITE_OK;
-  }
+  assert( (rc&0xff)==rc );
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 
 /*
-** Reset the aggregate accumulator.
+** This function is invoked by the vdbe to call the xDestroy method
+** of the virtual table named zTab in database iDb. This occurs
+** when a DROP TABLE is mentioned.
 **
-** The aggregate accumulator is a set of memory cells that hold
-** intermediate results while calculating an aggregate.  This
-** routine simply stores NULLs in all of those memory cells.
+** This call is a no-op if zTab is not a virtual table.
 */
-static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
-  Vdbe *v = pParse->pVdbe;
-  int i;
-  struct AggInfo_func *pFunc;
-  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
-    return;
-  }
-  for(i=0; i<pAggInfo->nColumn; i++){
-    sqlite3VdbeAddOp2(v, OP_Null, 0, pAggInfo->aCol[i].iMem);
-  }
-  for(pFunc=pAggInfo->aFunc, i=0; i<pAggInfo->nFunc; i++, pFunc++){
-    sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem);
-    if( pFunc->iDistinct>=0 ){
-      Expr *pE = pFunc->pExpr;
-      if( pE->pList==0 || pE->pList->nExpr!=1 ){
-        sqlite3ErrorMsg(pParse, "DISTINCT in aggregate must be followed "
-           "by an expression");
-        pFunc->iDistinct = -1;
-      }else{
-        KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->pList);
-        sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0,
-                          (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
-      }
+SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab){
+  int rc = SQLITE_OK;
+  Table *pTab;
+
+  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
+  if( ALWAYS(pTab!=0 && pTab->pVTable!=0) ){
+    VTable *p = vtabDisconnectAll(db, pTab);
+
+    rc = sqlite3SafetyOff(db);
+    assert( rc==SQLITE_OK );
+    rc = p->pMod->pModule->xDestroy(p->pVtab);
+    (void)sqlite3SafetyOn(db);
+
+    /* Remove the sqlite3_vtab* from the aVTrans[] array, if applicable */
+    if( rc==SQLITE_OK ){
+      assert( pTab->pVTable==p && p->pNext==0 );
+      p->pVtab = 0;
+      pTab->pVTable = 0;
+      sqlite3VtabUnlock(p);
     }
   }
+
+  return rc;
 }
 
 /*
-** Invoke the OP_AggFinalize opcode for every aggregate function
-** in the AggInfo structure.
+** This function invokes either the xRollback or xCommit method
+** of each of the virtual tables in the sqlite3.aVTrans array. The method
+** called is identified by the second argument, "offset", which is
+** the offset of the method to call in the sqlite3_module structure.
+**
+** The array is cleared after invoking the callbacks. 
 */
-static void finalizeAggFunctions(Parse *pParse, AggInfo *pAggInfo){
-  Vdbe *v = pParse->pVdbe;
+static void callFinaliser(sqlite3 *db, int offset){
   int i;
-  struct AggInfo_func *pF;
-  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
-    ExprList *pList = pF->pExpr->pList;
-    sqlite3VdbeAddOp4(v, OP_AggFinal, pF->iMem, pList ? pList->nExpr : 0, 0,
-                      (void*)pF->pFunc, P4_FUNCDEF);
+  if( db->aVTrans ){
+    for(i=0; i<db->nVTrans; i++){
+      VTable *pVTab = db->aVTrans[i];
+      sqlite3_vtab *p = pVTab->pVtab;
+      if( p ){
+        int (*x)(sqlite3_vtab *);
+        x = *(int (**)(sqlite3_vtab *))((char *)p->pModule + offset);
+        if( x ) x(p);
+      }
+      sqlite3VtabUnlock(pVTab);
+    }
+    sqlite3DbFree(db, db->aVTrans);
+    db->nVTrans = 0;
+    db->aVTrans = 0;
   }
 }
 
 /*
-** Update the accumulator memory cells for an aggregate based on
-** the current cursor position.
+** Invoke the xSync method of all virtual tables in the sqlite3.aVTrans
+** array. Return the error code for the first error that occurs, or
+** SQLITE_OK if all xSync operations are successful.
+**
+** Set *pzErrmsg to point to a buffer that should be released using 
+** sqlite3DbFree() containing an error message, if one is available.
 */
-static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
-  Vdbe *v = pParse->pVdbe;
+SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, char **pzErrmsg){
   int i;
-  struct AggInfo_func *pF;
-  struct AggInfo_col *pC;
+  int rc = SQLITE_OK;
+  int rcsafety;
+  VTable **aVTrans = db->aVTrans;
 
-  pAggInfo->directMode = 1;
-  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
-    int nArg;
-    int addrNext = 0;
-    int regAgg;
-    ExprList *pList = pF->pExpr->pList;
-    if( pList ){
-      nArg = pList->nExpr;
-      regAgg = sqlite3GetTempRange(pParse, nArg);
-      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
-    }else{
-      nArg = 0;
-      regAgg = 0;
-    }
-    if( pF->iDistinct>=0 ){
-      addrNext = sqlite3VdbeMakeLabel(v);
-      assert( nArg==1 );
-      codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg);
-    }
-    if( pF->pFunc->needCollSeq ){
-      CollSeq *pColl = 0;
-      struct ExprList_item *pItem;
-      int j;
-      assert( pList!=0 );  /* pList!=0 if pF->pFunc->needCollSeq is true */
-      for(j=0, pItem=pList->a; !pColl && j<nArg; j++, pItem++){
-        pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
-      }
-      if( !pColl ){
-        pColl = pParse->db->pDfltColl;
-      }
-      sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
-    }
-    sqlite3VdbeAddOp4(v, OP_AggStep, 0, regAgg, pF->iMem,
-                      (void*)pF->pFunc, P4_FUNCDEF);
-    sqlite3VdbeChangeP5(v, nArg);
-    sqlite3ReleaseTempRange(pParse, regAgg, nArg);
-    sqlite3ExprCacheAffinityChange(pParse, regAgg, nArg);
-    if( addrNext ){
-      sqlite3VdbeResolveLabel(v, addrNext);
+  rc = sqlite3SafetyOff(db);
+  db->aVTrans = 0;
+  for(i=0; rc==SQLITE_OK && i<db->nVTrans; i++){
+    int (*x)(sqlite3_vtab *);
+    sqlite3_vtab *pVtab = aVTrans[i]->pVtab;
+    if( pVtab && (x = pVtab->pModule->xSync)!=0 ){
+      rc = x(pVtab);
+      sqlite3DbFree(db, *pzErrmsg);
+      *pzErrmsg = pVtab->zErrMsg;
+      pVtab->zErrMsg = 0;
     }
   }
-  for(i=0, pC=pAggInfo->aCol; i<pAggInfo->nAccumulator; i++, pC++){
-    sqlite3ExprCode(pParse, pC->pExpr, pC->iMem);
+  db->aVTrans = aVTrans;
+  rcsafety = sqlite3SafetyOn(db);
+
+  if( rc==SQLITE_OK ){
+    rc = rcsafety;
   }
-  pAggInfo->directMode = 0;
+  return rc;
 }
 
-#if 0
 /*
-** This function is used when a SELECT statement is used to create a
-** temporary table for iterating through when running an INSTEAD OF
-** UPDATE or INSTEAD OF DELETE trigger. 
-**
-** If possible, the SELECT statement is modified so that NULL values
-** are stored in the temporary table for all columns for which the 
-** corresponding bit in argument mask is not set. If mask takes the
-** special value 0xffffffff, then all columns are populated.
+** Invoke the xRollback method of all virtual tables in the 
+** sqlite3.aVTrans array. Then clear the array itself.
 */
-SQLITE_PRIVATE void sqlite3SelectMask(Parse *pParse, Select *p, u32 mask){
-  if( p && !p->pPrior && !p->isDistinct && mask!=0xffffffff ){
-    ExprList *pEList;
-    int i;
-    sqlite3SelectResolve(pParse, p, 0);
-    pEList = p->pEList;
-    for(i=0; pEList && i<pEList->nExpr && i<32; i++){
-      if( !(mask&((u32)1<<i)) ){
-        sqlite3ExprDelete(pEList->a[i].pExpr);
-        pEList->a[i].pExpr = sqlite3Expr(pParse->db, TK_NULL, 0, 0, 0);
-      }
-    }
-  }
+SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db){
+  callFinaliser(db, offsetof(sqlite3_module,xRollback));
+  return SQLITE_OK;
 }
-#endif
 
 /*
-** Generate code for the given SELECT statement.
-**
-** The results are distributed in various ways depending on the
-** contents of the SelectDest structure pointed to by argument pDest
-** as follows:
-**
-**     pDest->eDest    Result
-**     ------------    -------------------------------------------
-**     SRT_Callback    Invoke the callback for each row of the result.
-**
-**     SRT_Mem         Store first result in memory cell pDest->iParm
-**
-**     SRT_Set         Store non-null results as keys of table pDest->iParm. 
-**                     Apply the affinity pDest->affinity before storing them.
-**
-**     SRT_Union       Store results as a key in a temporary table pDest->iParm.
-**
-**     SRT_Except      Remove results from the temporary table pDest->iParm.
-**
-**     SRT_Table       Store results in temporary table pDest->iParm
-**
-**     SRT_EphemTab    Create an temporary table pDest->iParm and store
-**                     the result there. The cursor is left open after
-**                     returning.
-**
-**     SRT_Subroutine  For each row returned, push the results onto the
-**                     vdbe stack and call the subroutine (via OP_Gosub)
-**                     at address pDest->iParm.
-**
-**     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
-**                     set is not empty.
-**
-**     SRT_Discard     Throw the results away.
-**
-** See the selectInnerLoop() function for a canonical listing of the 
-** allowed values of eDest and their meanings.
-**
-** This routine returns the number of errors.  If any errors are
-** encountered, then an appropriate error message is left in
-** pParse->zErrMsg.
-**
-** This routine does NOT free the Select structure passed in.  The
-** calling function needs to do that.
-**
-** The pParent, parentTab, and *pParentAgg fields are filled in if this
-** SELECT is a subquery.  This routine may try to combine this SELECT
-** with its parent to form a single flat query.  In so doing, it might
-** change the parent query from a non-aggregate to an aggregate query.
-** For that reason, the pParentAgg flag is passed as a pointer, so it
-** can be changed.
-**
-** Example 1:   The meaning of the pParent parameter.
-**
-**    SELECT * FROM t1 JOIN (SELECT x, count(*) FROM t2) JOIN t3;
-**    \                      \_______ subquery _______/        /
-**     \                                                      /
-**      \____________________ outer query ___________________/
+** Invoke the xCommit method of all virtual tables in the 
+** sqlite3.aVTrans array. Then clear the array itself.
+*/
+SQLITE_PRIVATE int sqlite3VtabCommit(sqlite3 *db){
+  callFinaliser(db, offsetof(sqlite3_module,xCommit));
+  return SQLITE_OK;
+}
+
+/*
+** If the virtual table pVtab supports the transaction interface
+** (xBegin/xRollback/xCommit and optionally xSync) and a transaction is
+** not currently open, invoke the xBegin method now.
 **
-** This routine is called for the outer query first.   For that call,
-** pParent will be NULL.  During the processing of the outer query, this 
-** routine is called recursively to handle the subquery.  For the recursive
-** call, pParent will point to the outer query.  Because the subquery is
-** the second element in a three-way join, the parentTab parameter will
-** be 1 (the 2nd value of a 0-indexed array.)
+** If the xBegin call is successful, place the sqlite3_vtab pointer
+** in the sqlite3.aVTrans array.
 */
-SQLITE_PRIVATE int sqlite3Select(
-  Parse *pParse,         /* The parser context */
-  Select *p,             /* The SELECT statement being coded. */
-  SelectDest *pDest,     /* What to do with the query results */
-  Select *pParent,       /* Another SELECT for which this is a sub-query */
-  int parentTab,         /* Index in pParent->pSrc of this query */
-  int *pParentAgg,       /* True if pParent uses aggregate functions */
-  char *aff              /* If eDest is SRT_Union, the affinity string */
-){
-  int i, j;              /* Loop counters */
-  WhereInfo *pWInfo;     /* Return from sqlite3WhereBegin() */
-  Vdbe *v;               /* The virtual machine under construction */
-  int isAgg;             /* True for select lists like "count(*)" */
-  ExprList *pEList;      /* List of columns to extract. */
-  SrcList *pTabList;     /* List of tables to select from */
-  Expr *pWhere;          /* The WHERE clause.  May be NULL */
-  ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
-  ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
-  Expr *pHaving;         /* The HAVING clause.  May be NULL */
-  int isDistinct;        /* True if the DISTINCT keyword is present */
-  int distinct;          /* Table to use for the distinct set */
-  int rc = 1;            /* Value to return from this function */
-  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
-  AggInfo sAggInfo;      /* Information used by aggregate queries */
-  int iEnd;              /* Address of the end of the query */
-  sqlite3 *db;           /* The database connection */
+SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *db, VTable *pVTab){
+  int rc = SQLITE_OK;
+  const sqlite3_module *pModule;
 
-  db = pParse->db;
-  if( p==0 || db->mallocFailed || pParse->nErr ){
-    return 1;
+  /* Special case: If db->aVTrans is NULL and db->nVTrans is greater
+  ** than zero, then this function is being called from within a
+  ** virtual module xSync() callback. It is illegal to write to 
+  ** virtual module tables in this case, so return SQLITE_LOCKED.
+  */
+  if( sqlite3VtabInSync(db) ){
+    return SQLITE_LOCKED;
   }
-  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
-  memset(&sAggInfo, 0, sizeof(sAggInfo));
+  if( !pVTab ){
+    return SQLITE_OK;
+  } 
+  pModule = pVTab->pVtab->pModule;
 
-  pOrderBy = p->pOrderBy;
-  if( IgnorableOrderby(pDest) ){
-    p->pOrderBy = 0;
+  if( pModule->xBegin ){
+    int i;
 
-    /* In these cases the DISTINCT operator makes no difference to the
-    ** results, so remove it if it were specified.
-    */
-    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
-           pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard);
-    p->isDistinct = 0;
-  }
-  if( sqlite3SelectResolve(pParse, p, 0) ){
-    goto select_end;
-  }
-  p->pOrderBy = pOrderBy;
 
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
-  /* If there is are a sequence of queries, do the earlier ones first.
-  */
-  if( p->pPrior ){
-    if( p->pRightmost==0 ){
-      Select *pLoop, *pRight = 0;
-      int cnt = 0;
-      int mxSelect;
-      for(pLoop=p; pLoop; pLoop=pLoop->pPrior, cnt++){
-        pLoop->pRightmost = p;
-        pLoop->pNext = pRight;
-        pRight = pLoop;
-      }
-      mxSelect = db->aLimit[SQLITE_LIMIT_COMPOUND_SELECT];
-      if( mxSelect && cnt>mxSelect ){
-        sqlite3ErrorMsg(pParse, "too many terms in compound SELECT");
-        return 1;
+    /* If pVtab is already in the aVTrans array, return early */
+    for(i=0; i<db->nVTrans; i++){
+      if( db->aVTrans[i]==pVTab ){
+        return SQLITE_OK;
       }
     }
-    return multiSelect(pParse, p, pDest, aff);
-  }
-#endif
 
-  /* Make local copies of the parameters for this query.
-  */
-  pTabList = p->pSrc;
-  pWhere = p->pWhere;
-  pGroupBy = p->pGroupBy;
-  pHaving = p->pHaving;
-  isAgg = p->isAgg;
-  isDistinct = p->isDistinct;
-  pEList = p->pEList;
-  if( pEList==0 ) goto select_end;
-
-  /* 
-  ** Do not even attempt to generate any code if we have already seen
-  ** errors before this routine starts.
-  */
-  if( pParse->nErr>0 ) goto select_end;
-
-  /* If writing to memory or generating a set
-  ** only a single column may be output.
-  */
-#ifndef SQLITE_OMIT_SUBQUERY
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    goto select_end;
+    /* Invoke the xBegin method */
+    rc = pModule->xBegin(pVTab->pVtab);
+    if( rc==SQLITE_OK ){
+      rc = addToVTrans(db, pVTab);
+    }
   }
-#endif
+  return rc;
+}
 
-  /* ORDER BY is ignored for some destinations.
-  */
-  if( IgnorableOrderby(pDest) ){
-    pOrderBy = 0;
-  }
+/*
+** The first parameter (pDef) is a function implementation.  The
+** second parameter (pExpr) is the first argument to this function.
+** If pExpr is a column in a virtual table, then let the virtual
+** table implementation have an opportunity to overload the function.
+**
+** This routine is used to allow virtual table implementations to
+** overload MATCH, LIKE, GLOB, and REGEXP operators.
+**
+** Return either the pDef argument (indicating no change) or a 
+** new FuncDef structure that is marked as ephemeral using the
+** SQLITE_FUNC_EPHEM flag.
+*/
+SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
+  sqlite3 *db,    /* Database connection for reporting malloc problems */
+  FuncDef *pDef,  /* Function to possibly overload */
+  int nArg,       /* Number of arguments to the function */
+  Expr *pExpr     /* First argument to the function */
+){
+  Table *pTab;
+  sqlite3_vtab *pVtab;
+  sqlite3_module *pMod;
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**) = 0;
+  void *pArg = 0;
+  FuncDef *pNew;
+  int rc = 0;
+  char *zLowerName;
+  unsigned char *z;
 
-  /* Begin generating code.
-  */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ) goto select_end;
 
-  /* Generate code for all sub-queries in the FROM clause
+  /* Check to see the left operand is a column in a virtual table */
+  if( NEVER(pExpr==0) ) return pDef;
+  if( pExpr->op!=TK_COLUMN ) return pDef;
+  pTab = pExpr->pTab;
+  if( NEVER(pTab==0) ) return pDef;
+  if( (pTab->tabFlags & TF_Virtual)==0 ) return pDef;
+  pVtab = sqlite3GetVTable(db, pTab)->pVtab;
+  assert( pVtab!=0 );
+  assert( pVtab->pModule!=0 );
+  pMod = (sqlite3_module *)pVtab->pModule;
+  if( pMod->xFindFunction==0 ) return pDef;
+ 
+  /* Call the xFindFunction method on the virtual table implementation
+  ** to see if the implementation wants to overload this function 
   */
-#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
-  for(i=0; i<pTabList->nSrc; i++){
-    const char *zSavedAuthContext = 0;
-    int needRestoreContext;
-    struct SrcList_item *pItem = &pTabList->a[i];
-    SelectDest dest;
-
-    if( pItem->pSelect==0 || pItem->isPopulated ) continue;
-    if( pItem->zName!=0 ){
-      zSavedAuthContext = pParse->zAuthContext;
-      pParse->zAuthContext = pItem->zName;
-      needRestoreContext = 1;
-    }else{
-      needRestoreContext = 0;
-    }
-    /* Increment Parse.nHeight by the height of the largest expression
-    ** tree refered to by this, the parent select. The child select
-    ** may contain expression trees of at most
-    ** (SQLITE_MAX_EXPR_DEPTH-Parse.nHeight) height. This is a bit
-    ** more conservative than necessary, but much easier than enforcing
-    ** an exact limit.
-    */
-    pParse->nHeight += sqlite3SelectExprHeight(p);
-    sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
-    sqlite3Select(pParse, pItem->pSelect, &dest, p, i, &isAgg, 0);
-    if( db->mallocFailed ){
-      goto select_end;
-    }
-    pParse->nHeight -= sqlite3SelectExprHeight(p);
-    if( needRestoreContext ){
-      pParse->zAuthContext = zSavedAuthContext;
-    }
-    pTabList = p->pSrc;
-    pWhere = p->pWhere;
-    if( !IgnorableOrderby(pDest) ){
-      pOrderBy = p->pOrderBy;
+  zLowerName = sqlite3DbStrDup(db, pDef->zName);
+  if( zLowerName ){
+    for(z=(unsigned char*)zLowerName; *z; z++){
+      *z = sqlite3UpperToLower[*z];
     }
-    pGroupBy = p->pGroupBy;
-    pHaving = p->pHaving;
-    isDistinct = p->isDistinct;
-  }
-#endif
-
-  /* Check to see if this is a subquery that can be "flattened" into its parent.
-  ** If flattening is a possiblity, do so and return immediately.  
-  */
-#ifndef SQLITE_OMIT_VIEW
-  if( pParent && pParentAgg &&
-      flattenSubquery(db, pParent, parentTab, *pParentAgg, isAgg) ){
-    if( isAgg ) *pParentAgg = 1;
-    goto select_end;
-  }
-#endif
-
-  /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
-  ** GROUP BY may use an index, DISTINCT never does.
-  */
-  if( p->isDistinct && !p->isAgg && !p->pGroupBy ){
-    p->pGroupBy = sqlite3ExprListDup(db, p->pEList);
-    pGroupBy = p->pGroupBy;
-    p->isDistinct = 0;
-    isDistinct = 0;
+    rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
+    sqlite3DbFree(db, zLowerName);
   }
-
-  /* If there is an ORDER BY clause, then this sorting
-  ** index might end up being unused if the data can be 
-  ** extracted in pre-sorted order.  If that is the case, then the
-  ** OP_OpenEphemeral instruction will be changed to an OP_Noop once
-  ** we figure out that the sorting index is not needed.  The addrSortIndex
-  ** variable is used to facilitate that change.
-  */
-  if( pOrderBy ){
-    KeyInfo *pKeyInfo;
-    pKeyInfo = keyInfoFromExprList(pParse, pOrderBy);
-    pOrderBy->iECursor = pParse->nTab++;
-    p->addrOpenEphm[2] = addrSortIndex =
-      sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
-                           pOrderBy->iECursor, pOrderBy->nExpr+2, 0,
-                           (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
-  }else{
-    addrSortIndex = -1;
+  if( rc==0 ){
+    return pDef;
   }
 
-  /* If the output is destined for a temporary table, open that table.
-  */
-  if( pDest->eDest==SRT_EphemTab ){
-    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
+  /* Create a new ephemeral function definition for the overloaded
+  ** function */
+  pNew = sqlite3DbMallocZero(db, sizeof(*pNew)
+                             + sqlite3Strlen30(pDef->zName) + 1);
+  if( pNew==0 ){
+    return pDef;
   }
+  *pNew = *pDef;
+  pNew->zName = (char *)&pNew[1];
+  memcpy(pNew->zName, pDef->zName, sqlite3Strlen30(pDef->zName)+1);
+  pNew->xFunc = xFunc;
+  pNew->pUserData = pArg;
+  pNew->flags |= SQLITE_FUNC_EPHEM;
+  return pNew;
+}
 
-  /* Set the limiter.
-  */
-  iEnd = sqlite3VdbeMakeLabel(v);
-  computeLimitRegisters(pParse, p, iEnd);
+/*
+** Make sure virtual table pTab is contained in the pParse->apVirtualLock[]
+** array so that an OP_VBegin will get generated for it.  Add pTab to the
+** array if it is missing.  If pTab is already in the array, this routine
+** is a no-op.
+*/
+SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse *pParse, Table *pTab){
+  Parse *pToplevel = sqlite3ParseToplevel(pParse);
+  int i, n;
+  Table **apVtabLock;
 
-  /* Open a virtual index to use for the distinct set.
-  */
-  if( isDistinct ){
-    KeyInfo *pKeyInfo;
-    assert( isAgg || pGroupBy );
-    distinct = pParse->nTab++;
-    pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
-    sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
-                        (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+  assert( IsVirtual(pTab) );
+  for(i=0; i<pToplevel->nVtabLock; i++){
+    if( pTab==pToplevel->apVtabLock[i] ) return;
+  }
+  n = (pToplevel->nVtabLock+1)*sizeof(pToplevel->apVtabLock[0]);
+  apVtabLock = sqlite3_realloc(pToplevel->apVtabLock, n);
+  if( apVtabLock ){
+    pToplevel->apVtabLock = apVtabLock;
+    pToplevel->apVtabLock[pToplevel->nVtabLock++] = pTab;
   }else{
-    distinct = -1;
+    pToplevel->db->mallocFailed = 1;
   }
+}
 
-  /* Aggregate and non-aggregate queries are handled differently */
-  if( !isAgg && pGroupBy==0 ){
-    /* This case is for non-aggregate queries
-    ** Begin the database scan
-    */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy, 0);
-    if( pWInfo==0 ) goto select_end;
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-    /* If sorting index that was created by a prior OP_OpenEphemeral 
-    ** instruction ended up not being needed, then change the OP_OpenEphemeral
-    ** into an OP_Noop.
-    */
-    if( addrSortIndex>=0 && pOrderBy==0 ){
-      sqlite3VdbeChangeToNoop(v, addrSortIndex, 1);
-      p->addrOpenEphm[2] = -1;
-    }
+/************** End of vtab.c ************************************************/
+/************** Begin file where.c *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This module contains C code that generates VDBE code used to process
+** the WHERE clause of SQL statements.  This module is responsible for
+** generating the code that loops through a table looking for applicable
+** rows.  Indices are selected and used to speed the search when doing
+** so is applicable.  Because this module is responsible for selecting
+** indices, you might also think of this module as the "query optimizer".
+**
+** $Id: where.c,v 1.411 2009/07/31 06:14:52 danielk1977 Exp $
+*/
 
-    /* Use the standard inner loop
-    */
-    assert(!isDistinct);
-    selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, -1, pDest,
-                    pWInfo->iContinue, pWInfo->iBreak, aff);
+/*
+** Trace output macros
+*/
+#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3WhereTrace = 0;
+#endif
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+# define WHERETRACE(X)  if(sqlite3WhereTrace) sqlite3DebugPrintf X
+#else
+# define WHERETRACE(X)
+#endif
 
-    /* End the database scan loop.
-    */
-    sqlite3WhereEnd(pWInfo);
-  }else{
-    /* This is the processing for aggregate queries */
-    NameContext sNC;    /* Name context for processing aggregate information */
-    int iAMem;          /* First Mem address for storing current GROUP BY */
-    int iBMem;          /* First Mem address for previous GROUP BY */
-    int iUseFlag;       /* Mem address holding flag indicating that at least
-                        ** one row of the input to the aggregator has been
-                        ** processed */
-    int iAbortFlag;     /* Mem address which causes query abort if positive */
-    int groupBySort;    /* Rows come from source in GROUP BY order */
+/* Forward reference
+*/
+typedef struct WhereClause WhereClause;
+typedef struct WhereMaskSet WhereMaskSet;
+typedef struct WhereOrInfo WhereOrInfo;
+typedef struct WhereAndInfo WhereAndInfo;
+typedef struct WhereCost WhereCost;
 
+/*
+** The query generator uses an array of instances of this structure to
+** help it analyze the subexpressions of the WHERE clause.  Each WHERE
+** clause subexpression is separated from the others by AND operators,
+** usually, or sometimes subexpressions separated by OR.
+**
+** All WhereTerms are collected into a single WhereClause structure.  
+** The following identity holds:
+**
+**        WhereTerm.pWC->a[WhereTerm.idx] == WhereTerm
+**
+** When a term is of the form:
+**
+**              X <op> <expr>
+**
+** where X is a column name and <op> is one of certain operators,
+** then WhereTerm.leftCursor and WhereTerm.u.leftColumn record the
+** cursor number and column number for X.  WhereTerm.eOperator records
+** the <op> using a bitmask encoding defined by WO_xxx below.  The
+** use of a bitmask encoding for the operator allows us to search
+** quickly for terms that match any of several different operators.
+**
+** A WhereTerm might also be two or more subterms connected by OR:
+**
+**         (t1.X <op> <expr>) OR (t1.Y <op> <expr>) OR ....
+**
+** In this second case, wtFlag as the TERM_ORINFO set and eOperator==WO_OR
+** and the WhereTerm.u.pOrInfo field points to auxiliary information that
+** is collected about the
+**
+** If a term in the WHERE clause does not match either of the two previous
+** categories, then eOperator==0.  The WhereTerm.pExpr field is still set
+** to the original subexpression content and wtFlags is set up appropriately
+** but no other fields in the WhereTerm object are meaningful.
+**
+** When eOperator!=0, prereqRight and prereqAll record sets of cursor numbers,
+** but they do so indirectly.  A single WhereMaskSet structure translates
+** cursor number into bits and the translated bit is stored in the prereq
+** fields.  The translation is used in order to maximize the number of
+** bits that will fit in a Bitmask.  The VDBE cursor numbers might be
+** spread out over the non-negative integers.  For example, the cursor
+** numbers might be 3, 8, 9, 10, 20, 23, 41, and 45.  The WhereMaskSet
+** translates these sparse cursor numbers into consecutive integers
+** beginning with 0 in order to make the best possible use of the available
+** bits in the Bitmask.  So, in the example above, the cursor numbers
+** would be mapped into integers 0 through 7.
+**
+** The number of terms in a join is limited by the number of bits
+** in prereqRight and prereqAll.  The default is 64 bits, hence SQLite
+** is only able to process joins with 64 or fewer tables.
+*/
+typedef struct WhereTerm WhereTerm;
+struct WhereTerm {
+  Expr *pExpr;            /* Pointer to the subexpression that is this term */
+  int iParent;            /* Disable pWC->a[iParent] when this term disabled */
+  int leftCursor;         /* Cursor number of X in "X <op> <expr>" */
+  union {
+    int leftColumn;         /* Column number of X in "X <op> <expr>" */
+    WhereOrInfo *pOrInfo;   /* Extra information if eOperator==WO_OR */
+    WhereAndInfo *pAndInfo; /* Extra information if eOperator==WO_AND */
+  } u;
+  u16 eOperator;          /* A WO_xx value describing <op> */
+  u8 wtFlags;             /* TERM_xxx bit flags.  See below */
+  u8 nChild;              /* Number of children that must disable us */
+  WhereClause *pWC;       /* The clause this term is part of */
+  Bitmask prereqRight;    /* Bitmask of tables used by pExpr->pRight */
+  Bitmask prereqAll;      /* Bitmask of tables referenced by pExpr */
+};
 
-    /* The following variables hold addresses or labels for parts of the
-    ** virtual machine program we are putting together */
-    int addrOutputRow;      /* Start of subroutine that outputs a result row */
-    int addrSetAbort;       /* Set the abort flag and return */
-    int addrInitializeLoop; /* Start of code that initializes the input loop */
-    int addrTopOfLoop;      /* Top of the input loop */
-    int addrGroupByChange;  /* Code that runs when any GROUP BY term changes */
-    int addrProcessRow;     /* Code to process a single input row */
-    int addrEnd;            /* End of all processing */
-    int addrSortingIdx;     /* The OP_OpenEphemeral for the sorting index */
-    int addrReset;          /* Subroutine for resetting the accumulator */
+/*
+** Allowed values of WhereTerm.wtFlags
+*/
+#define TERM_DYNAMIC    0x01   /* Need to call sqlite3ExprDelete(db, pExpr) */
+#define TERM_VIRTUAL    0x02   /* Added by the optimizer.  Do not code */
+#define TERM_CODED      0x04   /* This term is already coded */
+#define TERM_COPIED     0x08   /* Has a child */
+#define TERM_ORINFO     0x10   /* Need to free the WhereTerm.u.pOrInfo object */
+#define TERM_ANDINFO    0x20   /* Need to free the WhereTerm.u.pAndInfo obj */
+#define TERM_OR_OK      0x40   /* Used during OR-clause processing */
 
-    addrEnd = sqlite3VdbeMakeLabel(v);
+/*
+** An instance of the following structure holds all information about a
+** WHERE clause.  Mostly this is a container for one or more WhereTerms.
+*/
+struct WhereClause {
+  Parse *pParse;           /* The parser context */
+  WhereMaskSet *pMaskSet;  /* Mapping of table cursor numbers to bitmasks */
+  Bitmask vmask;           /* Bitmask identifying virtual table cursors */
+  u8 op;                   /* Split operator.  TK_AND or TK_OR */
+  int nTerm;               /* Number of terms */
+  int nSlot;               /* Number of entries in a[] */
+  WhereTerm *a;            /* Each a[] describes a term of the WHERE cluase */
+#if defined(SQLITE_SMALL_STACK)
+  WhereTerm aStatic[1];    /* Initial static space for a[] */
+#else
+  WhereTerm aStatic[8];    /* Initial static space for a[] */
+#endif
+};
 
-    /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in
-    ** sAggInfo for all TK_AGG_FUNCTION nodes in expressions of the
-    ** SELECT statement.
-    */
-    memset(&sNC, 0, sizeof(sNC));
-    sNC.pParse = pParse;
-    sNC.pSrcList = pTabList;
-    sNC.pAggInfo = &sAggInfo;
-    sAggInfo.nSortingColumn = pGroupBy ? pGroupBy->nExpr+1 : 0;
-    sAggInfo.pGroupBy = pGroupBy;
-    sqlite3ExprAnalyzeAggList(&sNC, pEList);
-    sqlite3ExprAnalyzeAggList(&sNC, pOrderBy);
-    if( pHaving ){
-      sqlite3ExprAnalyzeAggregates(&sNC, pHaving);
-    }
-    sAggInfo.nAccumulator = sAggInfo.nColumn;
-    for(i=0; i<sAggInfo.nFunc; i++){
-      sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->pList);
-    }
-    if( db->mallocFailed ) goto select_end;
+/*
+** A WhereTerm with eOperator==WO_OR has its u.pOrInfo pointer set to
+** a dynamically allocated instance of the following structure.
+*/
+struct WhereOrInfo {
+  WhereClause wc;          /* Decomposition into subterms */
+  Bitmask indexable;       /* Bitmask of all indexable tables in the clause */
+};
 
-    /* Processing for aggregates with GROUP BY is very different and
-    ** much more complex than aggregates without a GROUP BY.
-    */
-    if( pGroupBy ){
-      KeyInfo *pKeyInfo;  /* Keying information for the group by clause */
+/*
+** A WhereTerm with eOperator==WO_AND has its u.pAndInfo pointer set to
+** a dynamically allocated instance of the following structure.
+*/
+struct WhereAndInfo {
+  WhereClause wc;          /* The subexpression broken out */
+};
 
-      /* Create labels that we will be needing
-      */
-     
-      addrInitializeLoop = sqlite3VdbeMakeLabel(v);
-      addrGroupByChange = sqlite3VdbeMakeLabel(v);
-      addrProcessRow = sqlite3VdbeMakeLabel(v);
+/*
+** An instance of the following structure keeps track of a mapping
+** between VDBE cursor numbers and bits of the bitmasks in WhereTerm.
+**
+** The VDBE cursor numbers are small integers contained in 
+** SrcList_item.iCursor and Expr.iTable fields.  For any given WHERE 
+** clause, the cursor numbers might not begin with 0 and they might
+** contain gaps in the numbering sequence.  But we want to make maximum
+** use of the bits in our bitmasks.  This structure provides a mapping
+** from the sparse cursor numbers into consecutive integers beginning
+** with 0.
+**
+** If WhereMaskSet.ix[A]==B it means that The A-th bit of a Bitmask
+** corresponds VDBE cursor number B.  The A-th bit of a bitmask is 1<<A.
+**
+** For example, if the WHERE clause expression used these VDBE
+** cursors:  4, 5, 8, 29, 57, 73.  Then the  WhereMaskSet structure
+** would map those cursor numbers into bits 0 through 5.
+**
+** Note that the mapping is not necessarily ordered.  In the example
+** above, the mapping might go like this:  4->3, 5->1, 8->2, 29->0,
+** 57->5, 73->4.  Or one of 719 other combinations might be used. It
+** does not really matter.  What is important is that sparse cursor
+** numbers all get mapped into bit numbers that begin with 0 and contain
+** no gaps.
+*/
+struct WhereMaskSet {
+  int n;                        /* Number of assigned cursor values */
+  int ix[BMS];                  /* Cursor assigned to each bit */
+};
 
-      /* If there is a GROUP BY clause we might need a sorting index to
-      ** implement it.  Allocate that sorting index now.  If it turns out
-      ** that we do not need it after all, the OpenEphemeral instruction
-      ** will be converted into a Noop.  
-      */
-      sAggInfo.sortingIdx = pParse->nTab++;
-      pKeyInfo = keyInfoFromExprList(pParse, pGroupBy);
-      addrSortingIdx = sqlite3VdbeAddOp4(v, OP_OpenEphemeral, 
-          sAggInfo.sortingIdx, sAggInfo.nSortingColumn, 
-          0, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+/*
+** A WhereCost object records a lookup strategy and the estimated
+** cost of pursuing that strategy.
+*/
+struct WhereCost {
+  WherePlan plan;    /* The lookup strategy */
+  double rCost;      /* Overall cost of pursuing this search strategy */
+  double nRow;       /* Estimated number of output rows */
+  Bitmask used;      /* Bitmask of cursors used by this plan */
+};
 
-      /* Initialize memory locations used by GROUP BY aggregate processing
-      */
-      iUseFlag = ++pParse->nMem;
-      iAbortFlag = ++pParse->nMem;
-      iAMem = pParse->nMem + 1;
-      pParse->nMem += pGroupBy->nExpr;
-      iBMem = pParse->nMem + 1;
-      pParse->nMem += pGroupBy->nExpr;
-      sqlite3VdbeAddOp2(v, OP_Integer, 0, iAbortFlag);
-      VdbeComment((v, "clear abort flag"));
-      sqlite3VdbeAddOp2(v, OP_Integer, 0, iUseFlag);
-      VdbeComment((v, "indicate accumulator empty"));
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrInitializeLoop);
+/*
+** Bitmasks for the operators that indices are able to exploit.  An
+** OR-ed combination of these values can be used when searching for
+** terms in the where clause.
+*/
+#define WO_IN     0x001
+#define WO_EQ     0x002
+#define WO_LT     (WO_EQ<<(TK_LT-TK_EQ))
+#define WO_LE     (WO_EQ<<(TK_LE-TK_EQ))
+#define WO_GT     (WO_EQ<<(TK_GT-TK_EQ))
+#define WO_GE     (WO_EQ<<(TK_GE-TK_EQ))
+#define WO_MATCH  0x040
+#define WO_ISNULL 0x080
+#define WO_OR     0x100       /* Two or more OR-connected terms */
+#define WO_AND    0x200       /* Two or more AND-connected terms */
 
-      /* Generate a subroutine that outputs a single row of the result
-      ** set.  This subroutine first looks at the iUseFlag.  If iUseFlag
-      ** is less than or equal to zero, the subroutine is a no-op.  If
-      ** the processing calls for the query to abort, this subroutine
-      ** increments the iAbortFlag memory location before returning in
-      ** order to signal the caller to abort.
-      */
-      addrSetAbort = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag);
-      VdbeComment((v, "set abort flag"));
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      addrOutputRow = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2);
-      VdbeComment((v, "Groupby result generator entry point"));
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      finalizeAggFunctions(pParse, &sAggInfo);
-      if( pHaving ){
-        sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
-      }
-      selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy,
-                      distinct, pDest,
-                      addrOutputRow+1, addrSetAbort, aff);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      VdbeComment((v, "end groupby result generator"));
+#define WO_ALL    0xfff       /* Mask of all possible WO_* values */
+#define WO_SINGLE 0x0ff       /* Mask of all non-compound WO_* values */
 
-      /* Generate a subroutine that will reset the group-by accumulator
-      */
-      addrReset = sqlite3VdbeCurrentAddr(v);
-      resetAccumulator(pParse, &sAggInfo);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
+/*
+** Value for wsFlags returned by bestIndex() and stored in
+** WhereLevel.wsFlags.  These flags determine which search
+** strategies are appropriate.
+**
+** The least significant 12 bits is reserved as a mask for WO_ values above.
+** The WhereLevel.wsFlags field is usually set to WO_IN|WO_EQ|WO_ISNULL.
+** But if the table is the right table of a left join, WhereLevel.wsFlags
+** is set to WO_IN|WO_EQ.  The WhereLevel.wsFlags field can then be used as
+** the "op" parameter to findTerm when we are resolving equality constraints.
+** ISNULL constraints will then not be used on the right table of a left
+** join.  Tickets #2177 and #2189.
+*/
+#define WHERE_ROWID_EQ     0x00001000  /* rowid=EXPR or rowid IN (...) */
+#define WHERE_ROWID_RANGE  0x00002000  /* rowid<EXPR and/or rowid>EXPR */
+#define WHERE_COLUMN_EQ    0x00010000  /* x=EXPR or x IN (...) or x IS NULL */
+#define WHERE_COLUMN_RANGE 0x00020000  /* x<EXPR and/or x>EXPR */
+#define WHERE_COLUMN_IN    0x00040000  /* x IN (...) */
+#define WHERE_COLUMN_NULL  0x00080000  /* x IS NULL */
+#define WHERE_INDEXED      0x000f0000  /* Anything that uses an index */
+#define WHERE_IN_ABLE      0x000f1000  /* Able to support an IN operator */
+#define WHERE_TOP_LIMIT    0x00100000  /* x<EXPR or x<=EXPR constraint */
+#define WHERE_BTM_LIMIT    0x00200000  /* x>EXPR or x>=EXPR constraint */
+#define WHERE_IDX_ONLY     0x00800000  /* Use index only - omit table */
+#define WHERE_ORDERBY      0x01000000  /* Output will appear in correct order */
+#define WHERE_REVERSE      0x02000000  /* Scan in reverse order */
+#define WHERE_UNIQUE       0x04000000  /* Selects no more than one row */
+#define WHERE_VIRTUALTABLE 0x08000000  /* Use virtual-table processing */
+#define WHERE_MULTI_OR     0x10000000  /* OR using multiple indices */
 
-      /* Begin a loop that will extract all source rows in GROUP BY order.
-      ** This might involve two separate loops with an OP_Sort in between, or
-      ** it might be a single loop that uses an index to extract information
-      ** in the right order to begin with.
-      */
-      sqlite3VdbeResolveLabel(v, addrInitializeLoop);
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrReset);
-      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0);
-      if( pWInfo==0 ) goto select_end;
-      if( pGroupBy==0 ){
-        /* The optimizer is able to deliver rows in group by order so
-        ** we do not have to sort.  The OP_OpenEphemeral table will be
-        ** cancelled later because we still need to use the pKeyInfo
-        */
-        pGroupBy = p->pGroupBy;
-        groupBySort = 0;
-      }else{
-        /* Rows are coming out in undetermined order.  We have to push
-        ** each row into a sorting index, terminate the first loop,
-        ** then loop over the sorting index in order to get the output
-        ** in sorted order
-        */
-        int regBase;
-        int regRecord;
-        int nCol;
-        int nGroupBy;
+/*
+** Initialize a preallocated WhereClause structure.
+*/
+static void whereClauseInit(
+  WhereClause *pWC,        /* The WhereClause to be initialized */
+  Parse *pParse,           /* The parsing context */
+  WhereMaskSet *pMaskSet   /* Mapping from table cursor numbers to bitmasks */
+){
+  pWC->pParse = pParse;
+  pWC->pMaskSet = pMaskSet;
+  pWC->nTerm = 0;
+  pWC->nSlot = ArraySize(pWC->aStatic);
+  pWC->a = pWC->aStatic;
+  pWC->vmask = 0;
+}
 
-        groupBySort = 1;
-        nGroupBy = pGroupBy->nExpr;
-        nCol = nGroupBy + 1;
-        j = nGroupBy+1;
-        for(i=0; i<sAggInfo.nColumn; i++){
-          if( sAggInfo.aCol[i].iSorterColumn>=j ){
-            nCol++;
-            j++;
-          }
-        }
-        regBase = sqlite3GetTempRange(pParse, nCol);
-        sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0);
-        sqlite3VdbeAddOp2(v, OP_Sequence, sAggInfo.sortingIdx,regBase+nGroupBy);
-        j = nGroupBy+1;
-        for(i=0; i<sAggInfo.nColumn; i++){
-          struct AggInfo_col *pCol = &sAggInfo.aCol[i];
-          if( pCol->iSorterColumn>=j ){
-            int r1 = j + regBase;
-            int r2 = sqlite3ExprCodeGetColumn(pParse, 
-                               pCol->pTab, pCol->iColumn, pCol->iTable, r1, 0);
-            if( r1!=r2 ){
-              sqlite3VdbeAddOp2(v, OP_SCopy, r2, r1);
-            }
-            j++;
-          }
-        }
-        regRecord = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regRecord);
-        sqlite3VdbeAddOp2(v, OP_IdxInsert, sAggInfo.sortingIdx, regRecord);
-        sqlite3ReleaseTempReg(pParse, regRecord);
-        sqlite3ReleaseTempRange(pParse, regBase, nCol);
-        sqlite3WhereEnd(pWInfo);
-        sqlite3VdbeAddOp2(v, OP_Sort, sAggInfo.sortingIdx, addrEnd);
-        VdbeComment((v, "GROUP BY sort"));
-        sAggInfo.useSortingIdx = 1;
-      }
+/* Forward reference */
+static void whereClauseClear(WhereClause*);
 
-      /* Evaluate the current GROUP BY terms and store in b0, b1, b2...
-      ** (b0 is memory location iBMem+0, b1 is iBMem+1, and so forth)
-      ** Then compare the current GROUP BY terms against the GROUP BY terms
-      ** from the previous row currently stored in a0, a1, a2...
-      */
-      addrTopOfLoop = sqlite3VdbeCurrentAddr(v);
-      for(j=0; j<pGroupBy->nExpr; j++){
-        if( groupBySort ){
-          sqlite3VdbeAddOp3(v, OP_Column, sAggInfo.sortingIdx, j, iBMem+j);
-        }else{
-          sAggInfo.directMode = 1;
-          sqlite3ExprCode(pParse, pGroupBy->a[j].pExpr, iBMem+j);
-        }
-      }
-      for(j=pGroupBy->nExpr-1; j>=0; j--){
-        if( j==0 ){
-          sqlite3VdbeAddOp3(v, OP_Eq, iAMem+j, addrProcessRow, iBMem+j);
-        }else{
-          sqlite3VdbeAddOp3(v, OP_Ne, iAMem+j, addrGroupByChange, iBMem+j);
-        }
-        sqlite3VdbeChangeP4(v, -1, (void*)pKeyInfo->aColl[j], P4_COLLSEQ);
-        sqlite3VdbeChangeP5(v, SQLITE_NULLEQUAL);
-      }
+/*
+** Deallocate all memory associated with a WhereOrInfo object.
+*/
+static void whereOrInfoDelete(sqlite3 *db, WhereOrInfo *p){
+  whereClauseClear(&p->wc);
+  sqlite3DbFree(db, p);
+}
 
-      /* Generate code that runs whenever the GROUP BY changes.
-      ** Change in the GROUP BY are detected by the previous code
-      ** block.  If there were no changes, this block is skipped.
-      **
-      ** This code copies current group by terms in b0,b1,b2,...
-      ** over to a0,a1,a2.  It then calls the output subroutine
-      ** and resets the aggregate accumulator registers in preparation
-      ** for the next GROUP BY batch.
-      */
-      sqlite3VdbeResolveLabel(v, addrGroupByChange);
-      for(j=0; j<pGroupBy->nExpr; j++){
-        sqlite3ExprCodeMove(pParse, iBMem+j, iAMem+j);
-      }
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrOutputRow);
-      VdbeComment((v, "output one row"));
-      sqlite3VdbeAddOp2(v, OP_IfPos, iAbortFlag, addrEnd);
-      VdbeComment((v, "check abort flag"));
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrReset);
-      VdbeComment((v, "reset accumulator"));
+/*
+** Deallocate all memory associated with a WhereAndInfo object.
+*/
+static void whereAndInfoDelete(sqlite3 *db, WhereAndInfo *p){
+  whereClauseClear(&p->wc);
+  sqlite3DbFree(db, p);
+}
 
-      /* Update the aggregate accumulators based on the content of
-      ** the current row
-      */
-      sqlite3VdbeResolveLabel(v, addrProcessRow);
-      updateAccumulator(pParse, &sAggInfo);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iUseFlag);
-      VdbeComment((v, "indicate data in accumulator"));
+/*
+** Deallocate a WhereClause structure.  The WhereClause structure
+** itself is not freed.  This routine is the inverse of whereClauseInit().
+*/
+static void whereClauseClear(WhereClause *pWC){
+  int i;
+  WhereTerm *a;
+  sqlite3 *db = pWC->pParse->db;
+  for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
+    if( a->wtFlags & TERM_DYNAMIC ){
+      sqlite3ExprDelete(db, a->pExpr);
+    }
+    if( a->wtFlags & TERM_ORINFO ){
+      whereOrInfoDelete(db, a->u.pOrInfo);
+    }else if( a->wtFlags & TERM_ANDINFO ){
+      whereAndInfoDelete(db, a->u.pAndInfo);
+    }
+  }
+  if( pWC->a!=pWC->aStatic ){
+    sqlite3DbFree(db, pWC->a);
+  }
+}
 
-      /* End of the loop
-      */
-      if( groupBySort ){
-        sqlite3VdbeAddOp2(v, OP_Next, sAggInfo.sortingIdx, addrTopOfLoop);
-      }else{
-        sqlite3WhereEnd(pWInfo);
-        sqlite3VdbeChangeToNoop(v, addrSortingIdx, 1);
+/*
+** Add a single new WhereTerm entry to the WhereClause object pWC.
+** The new WhereTerm object is constructed from Expr p and with wtFlags.
+** The index in pWC->a[] of the new WhereTerm is returned on success.
+** 0 is returned if the new WhereTerm could not be added due to a memory
+** allocation error.  The memory allocation failure will be recorded in
+** the db->mallocFailed flag so that higher-level functions can detect it.
+**
+** This routine will increase the size of the pWC->a[] array as necessary.
+**
+** If the wtFlags argument includes TERM_DYNAMIC, then responsibility
+** for freeing the expression p is assumed by the WhereClause object pWC.
+** This is true even if this routine fails to allocate a new WhereTerm.
+**
+** WARNING:  This routine might reallocate the space used to store
+** WhereTerms.  All pointers to WhereTerms should be invalidated after
+** calling this routine.  Such pointers may be reinitialized by referencing
+** the pWC->a[] array.
+*/
+static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
+  WhereTerm *pTerm;
+  int idx;
+  if( pWC->nTerm>=pWC->nSlot ){
+    WhereTerm *pOld = pWC->a;
+    sqlite3 *db = pWC->pParse->db;
+    pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
+    if( pWC->a==0 ){
+      if( wtFlags & TERM_DYNAMIC ){
+        sqlite3ExprDelete(db, p);
       }
+      pWC->a = pOld;
+      return 0;
+    }
+    memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
+    if( pOld!=pWC->aStatic ){
+      sqlite3DbFree(db, pOld);
+    }
+    pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
+  }
+  pTerm = &pWC->a[idx = pWC->nTerm++];
+  pTerm->pExpr = p;
+  pTerm->wtFlags = wtFlags;
+  pTerm->pWC = pWC;
+  pTerm->iParent = -1;
+  return idx;
+}
 
-      /* Output the final row of result
-      */
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrOutputRow);
-      VdbeComment((v, "output final row"));
-      
-    } /* endif pGroupBy */
-    else {
-      ExprList *pMinMax = 0;
-      ExprList *pDel = 0;
-      u8 flag;
+/*
+** This routine identifies subexpressions in the WHERE clause where
+** each subexpression is separated by the AND operator or some other
+** operator specified in the op parameter.  The WhereClause structure
+** is filled with pointers to subexpressions.  For example:
+**
+**    WHERE  a=='hello' AND coalesce(b,11)<10 AND (c+12!=d OR c==22)
+**           \________/     \_______________/     \________________/
+**            slot[0]            slot[1]               slot[2]
+**
+** The original WHERE clause in pExpr is unaltered.  All this routine
+** does is make slot[] entries point to substructure within pExpr.
+**
+** In the previous sentence and in the diagram, "slot[]" refers to
+** the WhereClause.a[] array.  The slot[] array grows as needed to contain
+** all terms of the WHERE clause.
+*/
+static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
+  pWC->op = (u8)op;
+  if( pExpr==0 ) return;
+  if( pExpr->op!=op ){
+    whereClauseInsert(pWC, pExpr, 0);
+  }else{
+    whereSplit(pWC, pExpr->pLeft, op);
+    whereSplit(pWC, pExpr->pRight, op);
+  }
+}
 
-      /* Check if the query is of one of the following forms:
-      **
-      **   SELECT min(x) FROM ...
-      **   SELECT max(x) FROM ...
-      **
-      ** If it is, then ask the code in where.c to attempt to sort results
-      ** as if there was an "ORDER ON x" or "ORDER ON x DESC" clause. 
-      ** If where.c is able to produce results sorted in this order, then
-      ** add vdbe code to break out of the processing loop after the 
-      ** first iteration (since the first iteration of the loop is 
-      ** guaranteed to operate on the row with the minimum or maximum 
-      ** value of x, the only row required).
-      **
-      ** A special flag must be passed to sqlite3WhereBegin() to slightly
-      ** modify behaviour as follows:
-      **
-      **   + If the query is a "SELECT min(x)", then the loop coded by
-      **     where.c should not iterate over any values with a NULL value
-      **     for x.
-      **
-      **   + The optimizer code in where.c (the thing that decides which
-      **     index or indices to use) should place a different priority on 
-      **     satisfying the 'ORDER BY' clause than it does in other cases.
-      **     Refer to code and comments in where.c for details.
-      */
-      flag = minMaxQuery(pParse, p);
-      if( flag ){
-        pDel = pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->pList);
-        if( pMinMax && !db->mallocFailed ){
-          pMinMax->a[0].sortOrder = ((flag==WHERE_ORDERBY_MIN)?0:1);
-          pMinMax->a[0].pExpr->op = TK_COLUMN;
-        }
-      }
+/*
+** Initialize an expression mask set (a WhereMaskSet object)
+*/
+#define initMaskSet(P)  memset(P, 0, sizeof(*P))
 
-      /* This case runs if the aggregate has no GROUP BY clause.  The
-      ** processing is much simpler since there is only a single row
-      ** of output.
-      */
-      resetAccumulator(pParse, &sAggInfo);
-      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, flag);
-      if( pWInfo==0 ){
-        sqlite3ExprListDelete(pDel);
-        goto select_end;
-      }
-      updateAccumulator(pParse, &sAggInfo);
-      if( !pMinMax && flag ){
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak);
-        VdbeComment((v, "%s() by index", (flag==WHERE_ORDERBY_MIN?"min":"max")));
-      }
-      sqlite3WhereEnd(pWInfo);
-      finalizeAggFunctions(pParse, &sAggInfo);
-      pOrderBy = 0;
-      if( pHaving ){
-        sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL);
-      }
-      selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, -1, 
-                      pDest, addrEnd, addrEnd, aff);
+/*
+** Return the bitmask for the given cursor number.  Return 0 if
+** iCursor is not in the set.
+*/
+static Bitmask getMask(WhereMaskSet *pMaskSet, int iCursor){
+  int i;
+  assert( pMaskSet->n<=sizeof(Bitmask)*8 );
+  for(i=0; i<pMaskSet->n; i++){
+    if( pMaskSet->ix[i]==iCursor ){
+      return ((Bitmask)1)<<i;
+    }
+  }
+  return 0;
+}
+
+/*
+** Create a new mask for cursor iCursor.
+**
+** There is one cursor per table in the FROM clause.  The number of
+** tables in the FROM clause is limited by a test early in the
+** sqlite3WhereBegin() routine.  So we know that the pMaskSet->ix[]
+** array will never overflow.
+*/
+static void createMask(WhereMaskSet *pMaskSet, int iCursor){
+  assert( pMaskSet->n < ArraySize(pMaskSet->ix) );
+  pMaskSet->ix[pMaskSet->n++] = iCursor;
+}
 
-      sqlite3ExprListDelete(pDel);
+/*
+** This routine walks (recursively) an expression tree and generates
+** a bitmask indicating which tables are used in that expression
+** tree.
+**
+** In order for this routine to work, the calling function must have
+** previously invoked sqlite3ResolveExprNames() on the expression.  See
+** the header comment on that routine for additional information.
+** The sqlite3ResolveExprNames() routines looks for column names and
+** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
+** the VDBE cursor number of the table.  This routine just has to
+** translate the cursor numbers into bitmask values and OR all
+** the bitmasks together.
+*/
+static Bitmask exprListTableUsage(WhereMaskSet*, ExprList*);
+static Bitmask exprSelectTableUsage(WhereMaskSet*, Select*);
+static Bitmask exprTableUsage(WhereMaskSet *pMaskSet, Expr *p){
+  Bitmask mask = 0;
+  if( p==0 ) return 0;
+  if( p->op==TK_COLUMN ){
+    mask = getMask(pMaskSet, p->iTable);
+    return mask;
+  }
+  mask = exprTableUsage(pMaskSet, p->pRight);
+  mask |= exprTableUsage(pMaskSet, p->pLeft);
+  if( ExprHasProperty(p, EP_xIsSelect) ){
+    mask |= exprSelectTableUsage(pMaskSet, p->x.pSelect);
+  }else{
+    mask |= exprListTableUsage(pMaskSet, p->x.pList);
+  }
+  return mask;
+}
+static Bitmask exprListTableUsage(WhereMaskSet *pMaskSet, ExprList *pList){
+  int i;
+  Bitmask mask = 0;
+  if( pList ){
+    for(i=0; i<pList->nExpr; i++){
+      mask |= exprTableUsage(pMaskSet, pList->a[i].pExpr);
     }
-    sqlite3VdbeResolveLabel(v, addrEnd);
-    
-  } /* endif aggregate query */
+  }
+  return mask;
+}
+static Bitmask exprSelectTableUsage(WhereMaskSet *pMaskSet, Select *pS){
+  Bitmask mask = 0;
+  while( pS ){
+    mask |= exprListTableUsage(pMaskSet, pS->pEList);
+    mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
+    mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
+    mask |= exprTableUsage(pMaskSet, pS->pWhere);
+    mask |= exprTableUsage(pMaskSet, pS->pHaving);
+    pS = pS->pPrior;
+  }
+  return mask;
+}
 
-  /* If there is an ORDER BY clause, then we need to sort the results
-  ** and send them to the callback one by one.
-  */
-  if( pOrderBy ){
-    generateSortTail(pParse, p, v, pEList->nExpr, pDest);
+/*
+** Return TRUE if the given operator is one of the operators that is
+** allowed for an indexable WHERE clause term.  The allowed operators are
+** "=", "<", ">", "<=", ">=", and "IN".
+*/
+static int allowedOp(int op){
+  assert( TK_GT>TK_EQ && TK_GT<TK_GE );
+  assert( TK_LT>TK_EQ && TK_LT<TK_GE );
+  assert( TK_LE>TK_EQ && TK_LE<TK_GE );
+  assert( TK_GE==TK_EQ+4 );
+  return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
+}
+
+/*
+** Swap two objects of type TYPE.
+*/
+#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
+
+/*
+** Commute a comparison operator.  Expressions of the form "X op Y"
+** are converted into "Y op X".
+**
+** If a collation sequence is associated with either the left or right
+** side of the comparison, it remains associated with the same side after
+** the commutation. So "Y collate NOCASE op X" becomes 
+** "X collate NOCASE op Y". This is because any collation sequence on
+** the left hand side of a comparison overrides any collation sequence 
+** attached to the right. For the same reason the EP_ExpCollate flag
+** is not commuted.
+*/
+static void exprCommute(Parse *pParse, Expr *pExpr){
+  u16 expRight = (pExpr->pRight->flags & EP_ExpCollate);
+  u16 expLeft = (pExpr->pLeft->flags & EP_ExpCollate);
+  assert( allowedOp(pExpr->op) && pExpr->op!=TK_IN );
+  pExpr->pRight->pColl = sqlite3ExprCollSeq(pParse, pExpr->pRight);
+  pExpr->pLeft->pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+  SWAP(CollSeq*,pExpr->pRight->pColl,pExpr->pLeft->pColl);
+  pExpr->pRight->flags = (pExpr->pRight->flags & ~EP_ExpCollate) | expLeft;
+  pExpr->pLeft->flags = (pExpr->pLeft->flags & ~EP_ExpCollate) | expRight;
+  SWAP(Expr*,pExpr->pRight,pExpr->pLeft);
+  if( pExpr->op>=TK_GT ){
+    assert( TK_LT==TK_GT+2 );
+    assert( TK_GE==TK_LE+2 );
+    assert( TK_GT>TK_EQ );
+    assert( TK_GT<TK_LE );
+    assert( pExpr->op>=TK_GT && pExpr->op<=TK_GE );
+    pExpr->op = ((pExpr->op-TK_GT)^2)+TK_GT;
   }
+}
 
-#ifndef SQLITE_OMIT_SUBQUERY
-  /* If this was a subquery, we have now converted the subquery into a
-  ** temporary table.  So set the SrcList_item.isPopulated flag to prevent
-  ** this subquery from being evaluated again and to force the use of
-  ** the temporary table.
-  */
-  if( pParent ){
-    assert( pParent->pSrc->nSrc>parentTab );
-    assert( pParent->pSrc->a[parentTab].pSelect==p );
-    pParent->pSrc->a[parentTab].isPopulated = 1;
+/*
+** Translate from TK_xx operator to WO_xx bitmask.
+*/
+static u16 operatorMask(int op){
+  u16 c;
+  assert( allowedOp(op) );
+  if( op==TK_IN ){
+    c = WO_IN;
+  }else if( op==TK_ISNULL ){
+    c = WO_ISNULL;
+  }else{
+    assert( (WO_EQ<<(op-TK_EQ)) < 0x7fff );
+    c = (u16)(WO_EQ<<(op-TK_EQ));
   }
-#endif
+  assert( op!=TK_ISNULL || c==WO_ISNULL );
+  assert( op!=TK_IN || c==WO_IN );
+  assert( op!=TK_EQ || c==WO_EQ );
+  assert( op!=TK_LT || c==WO_LT );
+  assert( op!=TK_LE || c==WO_LE );
+  assert( op!=TK_GT || c==WO_GT );
+  assert( op!=TK_GE || c==WO_GE );
+  return c;
+}
 
-  /* Jump here to skip this query
-  */
-  sqlite3VdbeResolveLabel(v, iEnd);
+/*
+** Search for a term in the WHERE clause that is of the form "X <op> <expr>"
+** where X is a reference to the iColumn of table iCur and <op> is one of
+** the WO_xx operator codes specified by the op parameter.
+** Return a pointer to the term.  Return 0 if not found.
+*/
+static WhereTerm *findTerm(
+  WhereClause *pWC,     /* The WHERE clause to be searched */
+  int iCur,             /* Cursor number of LHS */
+  int iColumn,          /* Column number of LHS */
+  Bitmask notReady,     /* RHS must not overlap with this mask */
+  u32 op,               /* Mask of WO_xx values describing operator */
+  Index *pIdx           /* Must be compatible with this index, if not NULL */
+){
+  WhereTerm *pTerm;
+  int k;
+  assert( iCur>=0 );
+  op &= WO_ALL;
+  for(pTerm=pWC->a, k=pWC->nTerm; k; k--, pTerm++){
+    if( pTerm->leftCursor==iCur
+       && (pTerm->prereqRight & notReady)==0
+       && pTerm->u.leftColumn==iColumn
+       && (pTerm->eOperator & op)!=0
+    ){
+      if( pIdx && pTerm->eOperator!=WO_ISNULL ){
+        Expr *pX = pTerm->pExpr;
+        CollSeq *pColl;
+        char idxaff;
+        int j;
+        Parse *pParse = pWC->pParse;
 
-  /* The SELECT was successfully coded.   Set the return code to 0
-  ** to indicate no errors.
-  */
-  rc = 0;
+        idxaff = pIdx->pTable->aCol[iColumn].affinity;
+        if( !sqlite3IndexAffinityOk(pX, idxaff) ) continue;
 
-  /* Control jumps to here if an error is encountered above, or upon
-  ** successful coding of the SELECT.
-  */
-select_end:
+        /* Figure out the collation sequence required from an index for
+        ** it to be useful for optimising expression pX. Store this
+        ** value in variable pColl.
+        */
+        assert(pX->pLeft);
+        pColl = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
+        assert(pColl || pParse->nErr);
 
-  /* Identify column names if we will be using them in a callback.  This
-  ** step is skipped if the output is going to some other destination.
-  */
-  if( rc==SQLITE_OK && pDest->eDest==SRT_Callback ){
-    generateColumnNames(pParse, pTabList, pEList);
+        for(j=0; pIdx->aiColumn[j]!=iColumn; j++){
+          if( NEVER(j>=pIdx->nColumn) ) return 0;
+        }
+        if( pColl && sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
+      }
+      return pTerm;
+    }
   }
-
-  sqlite3_free(sAggInfo.aCol);
-  sqlite3_free(sAggInfo.aFunc);
-  return rc;
+  return 0;
 }
 
-#if defined(SQLITE_DEBUG)
+/* Forward reference */
+static void exprAnalyze(SrcList*, WhereClause*, int);
+
 /*
-*******************************************************************************
-** The following code is used for testing and debugging only.  The code
-** that follows does not appear in normal builds.
+** Call exprAnalyze on all terms in a WHERE clause.  
 **
-** These routines are used to print out the content of all or part of a 
-** parse structures such as Select or Expr.  Such printouts are useful
-** for helping to understand what is happening inside the code generator
-** during the execution of complex SELECT statements.
 **
-** These routine are not called anywhere from within the normal
-** code base.  Then are intended to be called from within the debugger
-** or from temporary "printf" statements inserted for debugging.
 */
-SQLITE_PRIVATE void sqlite3PrintExpr(Expr *p){
-  if( p->token.z && p->token.n>0 ){
-    sqlite3DebugPrintf("(%.*s", p->token.n, p->token.z);
-  }else{
-    sqlite3DebugPrintf("(%d", p->op);
+static void exprAnalyzeAll(
+  SrcList *pTabList,       /* the FROM clause */
+  WhereClause *pWC         /* the WHERE clause to be analyzed */
+){
+  int i;
+  for(i=pWC->nTerm-1; i>=0; i--){
+    exprAnalyze(pTabList, pWC, i);
   }
-  if( p->pLeft ){
-    sqlite3DebugPrintf(" ");
-    sqlite3PrintExpr(p->pLeft);
+}
+
+#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
+/*
+** Check to see if the given expression is a LIKE or GLOB operator that
+** can be optimized using inequality constraints.  Return TRUE if it is
+** so and false if not.
+**
+** In order for the operator to be optimizible, the RHS must be a string
+** literal that does not begin with a wildcard.  
+*/
+static int isLikeOrGlob(
+  Parse *pParse,    /* Parsing and code generating context */
+  Expr *pExpr,      /* Test this expression */
+  int *pnPattern,   /* Number of non-wildcard prefix characters */
+  int *pisComplete, /* True if the only wildcard is % in the last character */
+  int *pnoCase      /* True if uppercase is equivalent to lowercase */
+){
+  const char *z;             /* String on RHS of LIKE operator */
+  Expr *pRight, *pLeft;      /* Right and left size of LIKE operator */
+  ExprList *pList;           /* List of operands to the LIKE operator */
+  int c;                     /* One character in z[] */
+  int cnt;                   /* Number of non-wildcard prefix characters */
+  char wc[3];                /* Wildcard characters */
+  CollSeq *pColl;            /* Collating sequence for LHS */
+  sqlite3 *db = pParse->db;  /* Database connection */
+
+  if( !sqlite3IsLikeFunction(db, pExpr, pnoCase, wc) ){
+    return 0;
   }
-  if( p->pRight ){
-    sqlite3DebugPrintf(" ");
-    sqlite3PrintExpr(p->pRight);
+#ifdef SQLITE_EBCDIC
+  if( *pnoCase ) return 0;
+#endif
+  pList = pExpr->x.pList;
+  pRight = pList->a[0].pExpr;
+  if( pRight->op!=TK_STRING ){
+    return 0;
   }
-  sqlite3DebugPrintf(")");
-}
-SQLITE_PRIVATE void sqlite3PrintExprList(ExprList *pList){
-  int i;
-  for(i=0; i<pList->nExpr; i++){
-    sqlite3PrintExpr(pList->a[i].pExpr);
-    if( i<pList->nExpr-1 ){
-      sqlite3DebugPrintf(", ");
-    }
+  pLeft = pList->a[1].pExpr;
+  if( pLeft->op!=TK_COLUMN ){
+    return 0;
   }
-}
-SQLITE_PRIVATE void sqlite3PrintSelect(Select *p, int indent){
-  sqlite3DebugPrintf("%*sSELECT(%p) ", indent, "", p);
-  sqlite3PrintExprList(p->pEList);
-  sqlite3DebugPrintf("\n");
-  if( p->pSrc ){
-    char *zPrefix;
-    int i;
-    zPrefix = "FROM";
-    for(i=0; i<p->pSrc->nSrc; i++){
-      struct SrcList_item *pItem = &p->pSrc->a[i];
-      sqlite3DebugPrintf("%*s ", indent+6, zPrefix);
-      zPrefix = "";
-      if( pItem->pSelect ){
-        sqlite3DebugPrintf("(\n");
-        sqlite3PrintSelect(pItem->pSelect, indent+10);
-        sqlite3DebugPrintf("%*s)", indent+8, "");
-      }else if( pItem->zName ){
-        sqlite3DebugPrintf("%s", pItem->zName);
-      }
-      if( pItem->pTab ){
-        sqlite3DebugPrintf("(table: %s)", pItem->pTab->zName);
-      }
-      if( pItem->zAlias ){
-        sqlite3DebugPrintf(" AS %s", pItem->zAlias);
-      }
-      if( i<p->pSrc->nSrc-1 ){
-        sqlite3DebugPrintf(",");
-      }
-      sqlite3DebugPrintf("\n");
+  pColl = sqlite3ExprCollSeq(pParse, pLeft);
+  assert( pColl!=0 || pLeft->iColumn==-1 );
+  if( pColl==0 ) return 0;
+  if( (pColl->type!=SQLITE_COLL_BINARY || *pnoCase) &&
+      (pColl->type!=SQLITE_COLL_NOCASE || !*pnoCase) ){
+    return 0;
+  }
+  if( sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT ) return 0;
+  z = pRight->u.zToken;
+  if( ALWAYS(z) ){
+    cnt = 0;
+    while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){
+      cnt++;
+    }
+    if( cnt!=0 && c!=0 && 255!=(u8)z[cnt-1] ){
+      *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
+      *pnPattern = cnt;
+      return 1;
     }
   }
-  if( p->pWhere ){
-    sqlite3DebugPrintf("%*s WHERE ", indent, "");
-    sqlite3PrintExpr(p->pWhere);
-    sqlite3DebugPrintf("\n");
+  return 0;
+}
+#endif /* SQLITE_OMIT_LIKE_OPTIMIZATION */
+
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Check to see if the given expression is of the form
+**
+**         column MATCH expr
+**
+** If it is then return TRUE.  If not, return FALSE.
+*/
+static int isMatchOfColumn(
+  Expr *pExpr      /* Test this expression */
+){
+  ExprList *pList;
+
+  if( pExpr->op!=TK_FUNCTION ){
+    return 0;
   }
-  if( p->pGroupBy ){
-    sqlite3DebugPrintf("%*s GROUP BY ", indent, "");
-    sqlite3PrintExprList(p->pGroupBy);
-    sqlite3DebugPrintf("\n");
+  if( sqlite3StrICmp(pExpr->u.zToken,"match")!=0 ){
+    return 0;
   }
-  if( p->pHaving ){
-    sqlite3DebugPrintf("%*s HAVING ", indent, "");
-    sqlite3PrintExpr(p->pHaving);
-    sqlite3DebugPrintf("\n");
+  pList = pExpr->x.pList;
+  if( pList->nExpr!=2 ){
+    return 0;
   }
-  if( p->pOrderBy ){
-    sqlite3DebugPrintf("%*s ORDER BY ", indent, "");
-    sqlite3PrintExprList(p->pOrderBy);
-    sqlite3DebugPrintf("\n");
+  if( pList->a[1].pExpr->op != TK_COLUMN ){
+    return 0;
   }
+  return 1;
 }
-/* End of the structure debug printing code
-*****************************************************************************/
-#endif /* defined(SQLITE_TEST) || defined(SQLITE_DEBUG) */
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/************** End of select.c **********************************************/
-/************** Begin file table.c *******************************************/
 /*
-** 2001 September 15
+** If the pBase expression originated in the ON or USING clause of
+** a join, then transfer the appropriate markings over to derived.
+*/
+static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
+  pDerived->flags |= pBase->flags & EP_FromJoin;
+  pDerived->iRightJoinTable = pBase->iRightJoinTable;
+}
+
+#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
+/*
+** Analyze a term that consists of two or more OR-connected
+** subterms.  So in:
 **
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+**     ... WHERE  (a=5) AND (b=7 OR c=9 OR d=13) AND (d=13)
+**                          ^^^^^^^^^^^^^^^^^^^^
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** This routine analyzes terms such as the middle term in the above example.
+** A WhereOrTerm object is computed and attached to the term under
+** analysis, regardless of the outcome of the analysis.  Hence:
 **
-*************************************************************************
-** This file contains the sqlite3_get_table() and sqlite3_free_table()
-** interface routines.  These are just wrappers around the main
-** interface routine of sqlite3_exec().
+**     WhereTerm.wtFlags   |=  TERM_ORINFO
+**     WhereTerm.u.pOrInfo  =  a dynamically allocated WhereOrTerm object
 **
-** These routines are in a separate files so that they will not be linked
-** if they are not used.
+** The term being analyzed must have two or more of OR-connected subterms.
+** A single subterm might be a set of AND-connected sub-subterms.
+** Examples of terms under analysis:
+**
+**     (A)     t1.x=t2.y OR t1.x=t2.z OR t1.y=15 OR t1.z=t3.a+5
+**     (B)     x=expr1 OR expr2=x OR x=expr3
+**     (C)     t1.x=t2.y OR (t1.x=t2.z AND t1.y=15)
+**     (D)     x=expr1 OR (y>11 AND y<22 AND z LIKE '*hello*')
+**     (E)     (p.a=1 AND q.b=2 AND r.c=3) OR (p.x=4 AND q.y=5 AND r.z=6)
+**
+** CASE 1:
+**
+** If all subterms are of the form T.C=expr for some single column of C
+** a single table T (as shown in example B above) then create a new virtual
+** term that is an equivalent IN expression.  In other words, if the term
+** being analyzed is:
+**
+**      x = expr1  OR  expr2 = x  OR  x = expr3
+**
+** then create a new virtual term like this:
+**
+**      x IN (expr1,expr2,expr3)
+**
+** CASE 2:
+**
+** If all subterms are indexable by a single table T, then set
+**
+**     WhereTerm.eOperator              =  WO_OR
+**     WhereTerm.u.pOrInfo->indexable  |=  the cursor number for table T
+**
+** A subterm is "indexable" if it is of the form
+** "T.C <op> <expr>" where C is any column of table T and 
+** <op> is one of "=", "<", "<=", ">", ">=", "IS NULL", or "IN".
+** A subterm is also indexable if it is an AND of two or more
+** subsubterms at least one of which is indexable.  Indexable AND 
+** subterms have their eOperator set to WO_AND and they have
+** u.pAndInfo set to a dynamically allocated WhereAndTerm object.
+**
+** From another point of view, "indexable" means that the subterm could
+** potentially be used with an index if an appropriate index exists.
+** This analysis does not consider whether or not the index exists; that
+** is something the bestIndex() routine will determine.  This analysis
+** only looks at whether subterms appropriate for indexing exist.
+**
+** All examples A through E above all satisfy case 2.  But if a term
+** also statisfies case 1 (such as B) we know that the optimizer will
+** always prefer case 1, so in that case we pretend that case 2 is not
+** satisfied.
+**
+** It might be the case that multiple tables are indexable.  For example,
+** (E) above is indexable on tables P, Q, and R.
+**
+** Terms that satisfy case 2 are candidates for lookup by using
+** separate indices to find rowids for each subterm and composing
+** the union of all rowids using a RowSet object.  This is similar
+** to "bitmap indices" in other database engines.
+**
+** OTHERWISE:
+**
+** If neither case 1 nor case 2 apply, then leave the eOperator set to
+** zero.  This term is not useful for search.
 */
+static void exprAnalyzeOrTerm(
+  SrcList *pSrc,            /* the FROM clause */
+  WhereClause *pWC,         /* the complete WHERE clause */
+  int idxTerm               /* Index of the OR-term to be analyzed */
+){
+  Parse *pParse = pWC->pParse;            /* Parser context */
+  sqlite3 *db = pParse->db;               /* Database connection */
+  WhereTerm *pTerm = &pWC->a[idxTerm];    /* The term to be analyzed */
+  Expr *pExpr = pTerm->pExpr;             /* The expression of the term */
+  WhereMaskSet *pMaskSet = pWC->pMaskSet; /* Table use masks */
+  int i;                                  /* Loop counters */
+  WhereClause *pOrWc;       /* Breakup of pTerm into subterms */
+  WhereTerm *pOrTerm;       /* A Sub-term within the pOrWc */
+  WhereOrInfo *pOrInfo;     /* Additional information associated with pTerm */
+  Bitmask chngToIN;         /* Tables that might satisfy case 1 */
+  Bitmask indexable;        /* Tables that are indexable, satisfying case 2 */
 
-#ifndef SQLITE_OMIT_GET_TABLE
+  /*
+  ** Break the OR clause into its separate subterms.  The subterms are
+  ** stored in a WhereClause structure containing within the WhereOrInfo
+  ** object that is attached to the original OR clause term.
+  */
+  assert( (pTerm->wtFlags & (TERM_DYNAMIC|TERM_ORINFO|TERM_ANDINFO))==0 );
+  assert( pExpr->op==TK_OR );
+  pTerm->u.pOrInfo = pOrInfo = sqlite3DbMallocZero(db, sizeof(*pOrInfo));
+  if( pOrInfo==0 ) return;
+  pTerm->wtFlags |= TERM_ORINFO;
+  pOrWc = &pOrInfo->wc;
+  whereClauseInit(pOrWc, pWC->pParse, pMaskSet);
+  whereSplit(pOrWc, pExpr, TK_OR);
+  exprAnalyzeAll(pSrc, pOrWc);
+  if( db->mallocFailed ) return;
+  assert( pOrWc->nTerm>=2 );
+
+  /*
+  ** Compute the set of tables that might satisfy cases 1 or 2.
+  */
+  indexable = ~(Bitmask)0;
+  chngToIN = ~(pWC->vmask);
+  for(i=pOrWc->nTerm-1, pOrTerm=pOrWc->a; i>=0 && indexable; i--, pOrTerm++){
+    if( (pOrTerm->eOperator & WO_SINGLE)==0 ){
+      WhereAndInfo *pAndInfo;
+      assert( pOrTerm->eOperator==0 );
+      assert( (pOrTerm->wtFlags & (TERM_ANDINFO|TERM_ORINFO))==0 );
+      chngToIN = 0;
+      pAndInfo = sqlite3DbMallocRaw(db, sizeof(*pAndInfo));
+      if( pAndInfo ){
+        WhereClause *pAndWC;
+        WhereTerm *pAndTerm;
+        int j;
+        Bitmask b = 0;
+        pOrTerm->u.pAndInfo = pAndInfo;
+        pOrTerm->wtFlags |= TERM_ANDINFO;
+        pOrTerm->eOperator = WO_AND;
+        pAndWC = &pAndInfo->wc;
+        whereClauseInit(pAndWC, pWC->pParse, pMaskSet);
+        whereSplit(pAndWC, pOrTerm->pExpr, TK_AND);
+        exprAnalyzeAll(pSrc, pAndWC);
+        testcase( db->mallocFailed );
+        if( !db->mallocFailed ){
+          for(j=0, pAndTerm=pAndWC->a; j<pAndWC->nTerm; j++, pAndTerm++){
+            assert( pAndTerm->pExpr );
+            if( allowedOp(pAndTerm->pExpr->op) ){
+              b |= getMask(pMaskSet, pAndTerm->leftCursor);
+            }
+          }
+        }
+        indexable &= b;
+      }
+    }else if( pOrTerm->wtFlags & TERM_COPIED ){
+      /* Skip this term for now.  We revisit it when we process the
+      ** corresponding TERM_VIRTUAL term */
+    }else{
+      Bitmask b;
+      b = getMask(pMaskSet, pOrTerm->leftCursor);
+      if( pOrTerm->wtFlags & TERM_VIRTUAL ){
+        WhereTerm *pOther = &pOrWc->a[pOrTerm->iParent];
+        b |= getMask(pMaskSet, pOther->leftCursor);
+      }
+      indexable &= b;
+      if( pOrTerm->eOperator!=WO_EQ ){
+        chngToIN = 0;
+      }else{
+        chngToIN &= b;
+      }
+    }
+  }
+
+  /*
+  ** Record the set of tables that satisfy case 2.  The set might be
+  ** empty.
+  */
+  pOrInfo->indexable = indexable;
+  pTerm->eOperator = indexable==0 ? 0 : WO_OR;
+
+  /*
+  ** chngToIN holds a set of tables that *might* satisfy case 1.  But
+  ** we have to do some additional checking to see if case 1 really
+  ** is satisfied.
+  **
+  ** chngToIN will hold either 0, 1, or 2 bits.  The 0-bit case means
+  ** that there is no possibility of transforming the OR clause into an
+  ** IN operator because one or more terms in the OR clause contain
+  ** something other than == on a column in the single table.  The 1-bit
+  ** case means that every term of the OR clause is of the form
+  ** "table.column=expr" for some single table.  The one bit that is set
+  ** will correspond to the common table.  We still need to check to make
+  ** sure the same column is used on all terms.  The 2-bit case is when
+  ** the all terms are of the form "table1.column=table2.column".  It
+  ** might be possible to form an IN operator with either table1.column
+  ** or table2.column as the LHS if either is common to every term of
+  ** the OR clause.
+  **
+  ** Note that terms of the form "table.column1=table.column2" (the
+  ** same table on both sizes of the ==) cannot be optimized.
+  */
+  if( chngToIN ){
+    int okToChngToIN = 0;     /* True if the conversion to IN is valid */
+    int iColumn = -1;         /* Column index on lhs of IN operator */
+    int iCursor = -1;         /* Table cursor common to all terms */
+    int j = 0;                /* Loop counter */
+
+    /* Search for a table and column that appears on one side or the
+    ** other of the == operator in every subterm.  That table and column
+    ** will be recorded in iCursor and iColumn.  There might not be any
+    ** such table and column.  Set okToChngToIN if an appropriate table
+    ** and column is found but leave okToChngToIN false if not found.
+    */
+    for(j=0; j<2 && !okToChngToIN; j++){
+      pOrTerm = pOrWc->a;
+      for(i=pOrWc->nTerm-1; i>=0; i--, pOrTerm++){
+        assert( pOrTerm->eOperator==WO_EQ );
+        pOrTerm->wtFlags &= ~TERM_OR_OK;
+        if( pOrTerm->leftCursor==iCursor ){
+          /* This is the 2-bit case and we are on the second iteration and
+          ** current term is from the first iteration.  So skip this term. */
+          assert( j==1 );
+          continue;
+        }
+        if( (chngToIN & getMask(pMaskSet, pOrTerm->leftCursor))==0 ){
+          /* This term must be of the form t1.a==t2.b where t2 is in the
+          ** chngToIN set but t1 is not.  This term will be either preceeded
+          ** or follwed by an inverted copy (t2.b==t1.a).  Skip this term 
+          ** and use its inversion. */
+          testcase( pOrTerm->wtFlags & TERM_COPIED );
+          testcase( pOrTerm->wtFlags & TERM_VIRTUAL );
+          assert( pOrTerm->wtFlags & (TERM_COPIED|TERM_VIRTUAL) );
+          continue;
+        }
+        iColumn = pOrTerm->u.leftColumn;
+        iCursor = pOrTerm->leftCursor;
+        break;
+      }
+      if( i<0 ){
+        /* No candidate table+column was found.  This can only occur
+        ** on the second iteration */
+        assert( j==1 );
+        assert( (chngToIN&(chngToIN-1))==0 );
+        assert( chngToIN==getMask(pMaskSet, iCursor) );
+        break;
+      }
+      testcase( j==1 );
+
+      /* We have found a candidate table and column.  Check to see if that
+      ** table and column is common to every term in the OR clause */
+      okToChngToIN = 1;
+      for(; i>=0 && okToChngToIN; i--, pOrTerm++){
+        assert( pOrTerm->eOperator==WO_EQ );
+        if( pOrTerm->leftCursor!=iCursor ){
+          pOrTerm->wtFlags &= ~TERM_OR_OK;
+        }else if( pOrTerm->u.leftColumn!=iColumn ){
+          okToChngToIN = 0;
+        }else{
+          int affLeft, affRight;
+          /* If the right-hand side is also a column, then the affinities
+          ** of both right and left sides must be such that no type
+          ** conversions are required on the right.  (Ticket #2249)
+          */
+          affRight = sqlite3ExprAffinity(pOrTerm->pExpr->pRight);
+          affLeft = sqlite3ExprAffinity(pOrTerm->pExpr->pLeft);
+          if( affRight!=0 && affRight!=affLeft ){
+            okToChngToIN = 0;
+          }else{
+            pOrTerm->wtFlags |= TERM_OR_OK;
+          }
+        }
+      }
+    }
+
+    /* At this point, okToChngToIN is true if original pTerm satisfies
+    ** case 1.  In that case, construct a new virtual term that is 
+    ** pTerm converted into an IN operator.
+    */
+    if( okToChngToIN ){
+      Expr *pDup;            /* A transient duplicate expression */
+      ExprList *pList = 0;   /* The RHS of the IN operator */
+      Expr *pLeft = 0;       /* The LHS of the IN operator */
+      Expr *pNew;            /* The complete IN operator */
+
+      for(i=pOrWc->nTerm-1, pOrTerm=pOrWc->a; i>=0; i--, pOrTerm++){
+        if( (pOrTerm->wtFlags & TERM_OR_OK)==0 ) continue;
+        assert( pOrTerm->eOperator==WO_EQ );
+        assert( pOrTerm->leftCursor==iCursor );
+        assert( pOrTerm->u.leftColumn==iColumn );
+        pDup = sqlite3ExprDup(db, pOrTerm->pExpr->pRight, 0);
+        pList = sqlite3ExprListAppend(pWC->pParse, pList, pDup);
+        pLeft = pOrTerm->pExpr->pLeft;
+      }
+      assert( pLeft!=0 );
+      pDup = sqlite3ExprDup(db, pLeft, 0);
+      pNew = sqlite3PExpr(pParse, TK_IN, pDup, 0, 0);
+      if( pNew ){
+        int idxNew;
+        transferJoinMarkings(pNew, pExpr);
+        assert( !ExprHasProperty(pNew, EP_xIsSelect) );
+        pNew->x.pList = pList;
+        idxNew = whereClauseInsert(pWC, pNew, TERM_VIRTUAL|TERM_DYNAMIC);
+        testcase( idxNew==0 );
+        exprAnalyze(pSrc, pWC, idxNew);
+        pTerm = &pWC->a[idxTerm];
+        pWC->a[idxNew].iParent = idxTerm;
+        pTerm->nChild = 1;
+      }else{
+        sqlite3ExprListDelete(db, pList);
+      }
+      pTerm->eOperator = 0;  /* case 1 trumps case 2 */
+    }
+  }
+}
+#endif /* !SQLITE_OMIT_OR_OPTIMIZATION && !SQLITE_OMIT_SUBQUERY */
 
-/*
-** This structure is used to pass data from sqlite3_get_table() through
-** to the callback function is uses to build the result.
-*/
-typedef struct TabResult {
-  char **azResult;
-  char *zErrMsg;
-  int nResult;
-  int nAlloc;
-  int nRow;
-  int nColumn;
-  int nData;
-  int rc;
-} TabResult;
 
 /*
-** This routine is called once for each row in the result table.  Its job
-** is to fill in the TabResult structure appropriately, allocating new
-** memory as necessary.
+** The input to this routine is an WhereTerm structure with only the
+** "pExpr" field filled in.  The job of this routine is to analyze the
+** subexpression and populate all the other fields of the WhereTerm
+** structure.
+**
+** If the expression is of the form "<expr> <op> X" it gets commuted
+** to the standard form of "X <op> <expr>".
+**
+** If the expression is of the form "X <op> Y" where both X and Y are
+** columns, then the original expression is unchanged and a new virtual
+** term of the form "Y <op> X" is added to the WHERE clause and
+** analyzed separately.  The original term is marked with TERM_COPIED
+** and the new term is marked with TERM_DYNAMIC (because it's pExpr
+** needs to be freed with the WhereClause) and TERM_VIRTUAL (because it
+** is a commuted copy of a prior term.)  The original term has nChild=1
+** and the copy has idxParent set to the index of the original term.
 */
-static int sqlite3_get_table_cb(void *pArg, int nCol, char **argv, char **colv){
-  TabResult *p = (TabResult*)pArg;
-  int need;
-  int i;
-  char *z;
+static void exprAnalyze(
+  SrcList *pSrc,            /* the FROM clause */
+  WhereClause *pWC,         /* the WHERE clause */
+  int idxTerm               /* Index of the term to be analyzed */
+){
+  WhereTerm *pTerm;                /* The term to be analyzed */
+  WhereMaskSet *pMaskSet;          /* Set of table index masks */
+  Expr *pExpr;                     /* The expression to be analyzed */
+  Bitmask prereqLeft;              /* Prerequesites of the pExpr->pLeft */
+  Bitmask prereqAll;               /* Prerequesites of pExpr */
+  Bitmask extraRight = 0;
+  int nPattern;
+  int isComplete;
+  int noCase;
+  int op;                          /* Top-level operator.  pExpr->op */
+  Parse *pParse = pWC->pParse;     /* Parsing context */
+  sqlite3 *db = pParse->db;        /* Database connection */
 
-  /* Make sure there is enough space in p->azResult to hold everything
-  ** we need to remember from this invocation of the callback.
-  */
-  if( p->nRow==0 && argv!=0 ){
-    need = nCol*2;
+  if( db->mallocFailed ){
+    return;
+  }
+  pTerm = &pWC->a[idxTerm];
+  pMaskSet = pWC->pMaskSet;
+  pExpr = pTerm->pExpr;
+  prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
+  op = pExpr->op;
+  if( op==TK_IN ){
+    assert( pExpr->pRight==0 );
+    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+      pTerm->prereqRight = exprSelectTableUsage(pMaskSet, pExpr->x.pSelect);
+    }else{
+      pTerm->prereqRight = exprListTableUsage(pMaskSet, pExpr->x.pList);
+    }
+  }else if( op==TK_ISNULL ){
+    pTerm->prereqRight = 0;
   }else{
-    need = nCol;
+    pTerm->prereqRight = exprTableUsage(pMaskSet, pExpr->pRight);
   }
-  if( p->nData + need >= p->nAlloc ){
-    char **azNew;
-    p->nAlloc = p->nAlloc*2 + need + 1;
-    azNew = sqlite3_realloc( p->azResult, sizeof(char*)*p->nAlloc );
-    if( azNew==0 ) goto malloc_failed;
-    p->azResult = azNew;
+  prereqAll = exprTableUsage(pMaskSet, pExpr);
+  if( ExprHasProperty(pExpr, EP_FromJoin) ){
+    Bitmask x = getMask(pMaskSet, pExpr->iRightJoinTable);
+    prereqAll |= x;
+    extraRight = x-1;  /* ON clause terms may not be used with an index
+                       ** on left table of a LEFT JOIN.  Ticket #3015 */
+  }
+  pTerm->prereqAll = prereqAll;
+  pTerm->leftCursor = -1;
+  pTerm->iParent = -1;
+  pTerm->eOperator = 0;
+  if( allowedOp(op) && (pTerm->prereqRight & prereqLeft)==0 ){
+    Expr *pLeft = pExpr->pLeft;
+    Expr *pRight = pExpr->pRight;
+    if( pLeft->op==TK_COLUMN ){
+      pTerm->leftCursor = pLeft->iTable;
+      pTerm->u.leftColumn = pLeft->iColumn;
+      pTerm->eOperator = operatorMask(op);
+    }
+    if( pRight && pRight->op==TK_COLUMN ){
+      WhereTerm *pNew;
+      Expr *pDup;
+      if( pTerm->leftCursor>=0 ){
+        int idxNew;
+        pDup = sqlite3ExprDup(db, pExpr, 0);
+        if( db->mallocFailed ){
+          sqlite3ExprDelete(db, pDup);
+          return;
+        }
+        idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
+        if( idxNew==0 ) return;
+        pNew = &pWC->a[idxNew];
+        pNew->iParent = idxTerm;
+        pTerm = &pWC->a[idxTerm];
+        pTerm->nChild = 1;
+        pTerm->wtFlags |= TERM_COPIED;
+      }else{
+        pDup = pExpr;
+        pNew = pTerm;
+      }
+      exprCommute(pParse, pDup);
+      pLeft = pDup->pLeft;
+      pNew->leftCursor = pLeft->iTable;
+      pNew->u.leftColumn = pLeft->iColumn;
+      pNew->prereqRight = prereqLeft;
+      pNew->prereqAll = prereqAll;
+      pNew->eOperator = operatorMask(pDup->op);
+    }
   }
 
-  /* If this is the first row, then generate an extra row containing
-  ** the names of all columns.
-  */
-  if( p->nRow==0 ){
-    p->nColumn = nCol;
-    for(i=0; i<nCol; i++){
-      z = sqlite3_mprintf("%s", colv[i]);
-      if( z==0 ) goto malloc_failed;
-      p->azResult[p->nData++] = z;
+#ifndef SQLITE_OMIT_BETWEEN_OPTIMIZATION
+  /* If a term is the BETWEEN operator, create two new virtual terms
+  ** that define the range that the BETWEEN implements.  For example:
+  **
+  **      a BETWEEN b AND c
+  **
+  ** is converted into:
+  **
+  **      (a BETWEEN b AND c) AND (a>=b) AND (a<=c)
+  **
+  ** The two new terms are added onto the end of the WhereClause object.
+  ** The new terms are "dynamic" and are children of the original BETWEEN
+  ** term.  That means that if the BETWEEN term is coded, the children are
+  ** skipped.  Or, if the children are satisfied by an index, the original
+  ** BETWEEN term is skipped.
+  */
+  else if( pExpr->op==TK_BETWEEN && pWC->op==TK_AND ){
+    ExprList *pList = pExpr->x.pList;
+    int i;
+    static const u8 ops[] = {TK_GE, TK_LE};
+    assert( pList!=0 );
+    assert( pList->nExpr==2 );
+    for(i=0; i<2; i++){
+      Expr *pNewExpr;
+      int idxNew;
+      pNewExpr = sqlite3PExpr(pParse, ops[i], 
+                             sqlite3ExprDup(db, pExpr->pLeft, 0),
+                             sqlite3ExprDup(db, pList->a[i].pExpr, 0), 0);
+      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
+      testcase( idxNew==0 );
+      exprAnalyze(pSrc, pWC, idxNew);
+      pTerm = &pWC->a[idxTerm];
+      pWC->a[idxNew].iParent = idxTerm;
     }
-  }else if( p->nColumn!=nCol ){
-    sqlite3_free(p->zErrMsg);
-    p->zErrMsg = sqlite3_mprintf(
-       "sqlite3_get_table() called with two or more incompatible queries"
-    );
-    p->rc = SQLITE_ERROR;
-    return 1;
+    pTerm->nChild = 2;
   }
+#endif /* SQLITE_OMIT_BETWEEN_OPTIMIZATION */
 
-  /* Copy over the row data
+#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
+  /* Analyze a term that is composed of two or more subterms connected by
+  ** an OR operator.
   */
-  if( argv!=0 ){
-    for(i=0; i<nCol; i++){
-      if( argv[i]==0 ){
-        z = 0;
-      }else{
-        int n = strlen(argv[i])+1;
-        z = sqlite3_malloc( n );
-        if( z==0 ) goto malloc_failed;
-        memcpy(z, argv[i], n);
-      }
-      p->azResult[p->nData++] = z;
-    }
-    p->nRow++;
+  else if( pExpr->op==TK_OR ){
+    assert( pWC->op==TK_AND );
+    exprAnalyzeOrTerm(pSrc, pWC, idxTerm);
+    pTerm = &pWC->a[idxTerm];
   }
-  return 0;
+#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
 
-malloc_failed:
-  p->rc = SQLITE_NOMEM;
-  return 1;
-}
+#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
+  /* Add constraints to reduce the search space on a LIKE or GLOB
+  ** operator.
+  **
+  ** A like pattern of the form "x LIKE 'abc%'" is changed into constraints
+  **
+  **          x>='abc' AND x<'abd' AND x LIKE 'abc%'
+  **
+  ** The last character of the prefix "abc" is incremented to form the
+  ** termination condition "abd".
+  */
+  if( isLikeOrGlob(pParse, pExpr, &nPattern, &isComplete, &noCase)
+         && pWC->op==TK_AND ){
+    Expr *pLeft, *pRight;
+    Expr *pStr1, *pStr2;
+    Expr *pNewExpr1, *pNewExpr2;
+    int idxNew1, idxNew2;
 
-/*
-** Query the database.  But instead of invoking a callback for each row,
-** malloc() for space to hold the result and return the entire results
-** at the conclusion of the call.
-**
-** The result that is written to ***pazResult is held in memory obtained
-** from malloc().  But the caller cannot free this memory directly.  
-** Instead, the entire table should be passed to sqlite3_free_table() when
-** the calling procedure is finished using it.
-*/
-SQLITE_API int sqlite3_get_table(
-  sqlite3 *db,                /* The database on which the SQL executes */
-  const char *zSql,           /* The SQL to be executed */
-  char ***pazResult,          /* Write the result table here */
-  int *pnRow,                 /* Write the number of rows in the result here */
-  int *pnColumn,              /* Write the number of columns of result here */
-  char **pzErrMsg             /* Write error messages here */
-){
-  int rc;
-  TabResult res;
+    pLeft = pExpr->x.pList->a[1].pExpr;
+    pRight = pExpr->x.pList->a[0].pExpr;
+    pStr1 = sqlite3Expr(db, TK_STRING, pRight->u.zToken);
+    if( pStr1 ) pStr1->u.zToken[nPattern] = 0;
+    pStr2 = sqlite3ExprDup(db, pStr1, 0);
+    if( !db->mallocFailed ){
+      u8 c, *pC;       /* Last character before the first wildcard */
+      pC = (u8*)&pStr2->u.zToken[nPattern-1];
+      c = *pC;
+      if( noCase ){
+        /* The point is to increment the last character before the first
+        ** wildcard.  But if we increment '@', that will push it into the
+        ** alphabetic range where case conversions will mess up the 
+        ** inequality.  To avoid this, make sure to also run the full
+        ** LIKE on all candidate expressions by clearing the isComplete flag
+        */
+        if( c=='A'-1 ) isComplete = 0;
 
-  *pazResult = 0;
-  if( pnColumn ) *pnColumn = 0;
-  if( pnRow ) *pnRow = 0;
-  res.zErrMsg = 0;
-  res.nResult = 0;
-  res.nRow = 0;
-  res.nColumn = 0;
-  res.nData = 1;
-  res.nAlloc = 20;
-  res.rc = SQLITE_OK;
-  res.azResult = sqlite3_malloc(sizeof(char*)*res.nAlloc );
-  if( res.azResult==0 ){
-     db->errCode = SQLITE_NOMEM;
-     return SQLITE_NOMEM;
-  }
-  res.azResult[0] = 0;
-  rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
-  assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
-  res.azResult[0] = (char*)res.nData;
-  if( (rc&0xff)==SQLITE_ABORT ){
-    sqlite3_free_table(&res.azResult[1]);
-    if( res.zErrMsg ){
-      if( pzErrMsg ){
-        sqlite3_free(*pzErrMsg);
-        *pzErrMsg = sqlite3_mprintf("%s",res.zErrMsg);
+        c = sqlite3UpperToLower[c];
       }
-      sqlite3_free(res.zErrMsg);
+      *pC = c + 1;
+    }
+    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft,0),pStr1,0);
+    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
+    testcase( idxNew1==0 );
+    exprAnalyze(pSrc, pWC, idxNew1);
+    pNewExpr2 = sqlite3PExpr(pParse, TK_LT, sqlite3ExprDup(db,pLeft,0),pStr2,0);
+    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
+    testcase( idxNew2==0 );
+    exprAnalyze(pSrc, pWC, idxNew2);
+    pTerm = &pWC->a[idxTerm];
+    if( isComplete ){
+      pWC->a[idxNew1].iParent = idxTerm;
+      pWC->a[idxNew2].iParent = idxTerm;
+      pTerm->nChild = 2;
     }
-    db->errCode = res.rc;  /* Assume 32-bit assignment is atomic */
-    return res.rc;
-  }
-  sqlite3_free(res.zErrMsg);
-  if( rc!=SQLITE_OK ){
-    sqlite3_free_table(&res.azResult[1]);
-    return rc;
   }
-  if( res.nAlloc>res.nData ){
-    char **azNew;
-    azNew = sqlite3_realloc( res.azResult, sizeof(char*)*(res.nData+1) );
-    if( azNew==0 ){
-      sqlite3_free_table(&res.azResult[1]);
-      db->errCode = SQLITE_NOMEM;
-      return SQLITE_NOMEM;
+#endif /* SQLITE_OMIT_LIKE_OPTIMIZATION */
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  /* Add a WO_MATCH auxiliary term to the constraint set if the
+  ** current expression is of the form:  column MATCH expr.
+  ** This information is used by the xBestIndex methods of
+  ** virtual tables.  The native query optimizer does not attempt
+  ** to do anything with MATCH functions.
+  */
+  if( isMatchOfColumn(pExpr) ){
+    int idxNew;
+    Expr *pRight, *pLeft;
+    WhereTerm *pNewTerm;
+    Bitmask prereqColumn, prereqExpr;
+
+    pRight = pExpr->x.pList->a[0].pExpr;
+    pLeft = pExpr->x.pList->a[1].pExpr;
+    prereqExpr = exprTableUsage(pMaskSet, pRight);
+    prereqColumn = exprTableUsage(pMaskSet, pLeft);
+    if( (prereqExpr & prereqColumn)==0 ){
+      Expr *pNewExpr;
+      pNewExpr = sqlite3PExpr(pParse, TK_MATCH, 
+                              0, sqlite3ExprDup(db, pRight, 0), 0);
+      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
+      testcase( idxNew==0 );
+      pNewTerm = &pWC->a[idxNew];
+      pNewTerm->prereqRight = prereqExpr;
+      pNewTerm->leftCursor = pLeft->iTable;
+      pNewTerm->u.leftColumn = pLeft->iColumn;
+      pNewTerm->eOperator = WO_MATCH;
+      pNewTerm->iParent = idxTerm;
+      pTerm = &pWC->a[idxTerm];
+      pTerm->nChild = 1;
+      pTerm->wtFlags |= TERM_COPIED;
+      pNewTerm->prereqAll = pTerm->prereqAll;
     }
-    res.nAlloc = res.nData+1;
-    res.azResult = azNew;
   }
-  *pazResult = &res.azResult[1];
-  if( pnColumn ) *pnColumn = res.nColumn;
-  if( pnRow ) *pnRow = res.nRow;
-  return rc;
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+  /* Prevent ON clause terms of a LEFT JOIN from being used to drive
+  ** an index for tables to the left of the join.
+  */
+  pTerm->prereqRight |= extraRight;
 }
 
 /*
-** This routine frees the space the sqlite3_get_table() malloced.
+** Return TRUE if any of the expressions in pList->a[iFirst...] contain
+** a reference to any table other than the iBase table.
 */
-SQLITE_API void sqlite3_free_table(
-  char **azResult            /* Result returned from from sqlite3_get_table() */
+static int referencesOtherTables(
+  ExprList *pList,          /* Search expressions in ths list */
+  WhereMaskSet *pMaskSet,   /* Mapping from tables to bitmaps */
+  int iFirst,               /* Be searching with the iFirst-th expression */
+  int iBase                 /* Ignore references to this table */
 ){
-  if( azResult ){
-    int i, n;
-    azResult--;
-    assert( azResult!=0 );
-    n = (int)azResult[0];
-    for(i=1; i<n; i++){ if( azResult[i] ) sqlite3_free(azResult[i]); }
-    sqlite3_free(azResult);
+  Bitmask allowed = ~getMask(pMaskSet, iBase);
+  while( iFirst<pList->nExpr ){
+    if( (exprTableUsage(pMaskSet, pList->a[iFirst++].pExpr)&allowed)!=0 ){
+      return 1;
+    }
   }
+  return 0;
 }
 
-#endif /* SQLITE_OMIT_GET_TABLE */
 
-/************** End of table.c ***********************************************/
-/************** Begin file trigger.c *****************************************/
 /*
+** This routine decides if pIdx can be used to satisfy the ORDER BY
+** clause.  If it can, it returns 1.  If pIdx cannot satisfy the
+** ORDER BY clause, this routine returns 0.
 **
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** pOrderBy is an ORDER BY clause from a SELECT statement.  pTab is the
+** left-most table in the FROM clause of that same SELECT statement and
+** the table has a cursor number of "base".  pIdx is an index on pTab.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** nEqCol is the number of columns of pIdx that are used as equality
+** constraints.  Any of these columns may be missing from the ORDER BY
+** clause and the match can still be a success.
 **
-*************************************************************************
-*
-*/
-
-#ifndef SQLITE_OMIT_TRIGGER
-/*
-** Delete a linked list of TriggerStep structures.
-*/
-SQLITE_PRIVATE void sqlite3DeleteTriggerStep(TriggerStep *pTriggerStep){
-  while( pTriggerStep ){
-    TriggerStep * pTmp = pTriggerStep;
-    pTriggerStep = pTriggerStep->pNext;
-
-    if( pTmp->target.dyn ) sqlite3_free((char*)pTmp->target.z);
-    sqlite3ExprDelete(pTmp->pWhere);
-    sqlite3ExprListDelete(pTmp->pExprList);
-    sqlite3SelectDelete(pTmp->pSelect);
-    sqlite3IdListDelete(pTmp->pIdList);
-
-    sqlite3_free(pTmp);
-  }
-}
-
-/*
-** This is called by the parser when it sees a CREATE TRIGGER statement
-** up to the point of the BEGIN before the trigger actions.  A Trigger
-** structure is generated based on the information available and stored
-** in pParse->pNewTrigger.  After the trigger actions have been parsed, the
-** sqlite3FinishTrigger() function is called to complete the trigger
-** construction process.
+** All terms of the ORDER BY that match against the index must be either
+** ASC or DESC.  (Terms of the ORDER BY clause past the end of a UNIQUE
+** index do not need to satisfy this constraint.)  The *pbRev value is
+** set to 1 if the ORDER BY clause is all DESC and it is set to 0 if
+** the ORDER BY clause is all ASC.
 */
-SQLITE_PRIVATE void sqlite3BeginTrigger(
-  Parse *pParse,      /* The parse context of the CREATE TRIGGER statement */
-  Token *pName1,      /* The name of the trigger */
-  Token *pName2,      /* The name of the trigger */
-  int tr_tm,          /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
-  int op,             /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
-  IdList *pColumns,   /* column list if this is an UPDATE OF trigger */
-  SrcList *pTableName,/* The name of the table/view the trigger applies to */
-  Expr *pWhen,        /* WHEN clause */
-  int isTemp,         /* True if the TEMPORARY keyword is present */
-  int noErr           /* Suppress errors if the trigger already exists */
+static int isSortingIndex(
+  Parse *pParse,          /* Parsing context */
+  WhereMaskSet *pMaskSet, /* Mapping from table cursor numbers to bitmaps */
+  Index *pIdx,            /* The index we are testing */
+  int base,               /* Cursor number for the table to be sorted */
+  ExprList *pOrderBy,     /* The ORDER BY clause */
+  int nEqCol,             /* Number of index columns with == constraints */
+  int *pbRev              /* Set to 1 if ORDER BY is DESC */
 ){
-  Trigger *pTrigger = 0;
-  Table *pTab;
-  char *zName = 0;        /* Name of the trigger */
+  int i, j;                       /* Loop counters */
+  int sortOrder = 0;              /* XOR of index and ORDER BY sort direction */
+  int nTerm;                      /* Number of ORDER BY terms */
+  struct ExprList_item *pTerm;    /* A term of the ORDER BY clause */
   sqlite3 *db = pParse->db;
-  int iDb;                /* The database to store the trigger in */
-  Token *pName;           /* The unqualified db name */
-  DbFixer sFix;
-  int iTabDb;
 
-  assert( pName1!=0 );   /* pName1->z might be NULL, but not pName1 itself */
-  assert( pName2!=0 );
-  if( isTemp ){
-    /* If TEMP was specified, then the trigger name may not be qualified. */
-    if( pName2->n>0 ){
-      sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
-      goto trigger_cleanup;
-    }
-    iDb = 1;
-    pName = pName1;
-  }else{
-    /* Figure out the db that the the trigger will be created in */
-    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
-    if( iDb<0 ){
-      goto trigger_cleanup;
-    }
-  }
+  assert( pOrderBy!=0 );
+  nTerm = pOrderBy->nExpr;
+  assert( nTerm>0 );
 
-  /* If the trigger name was unqualified, and the table is a temp table,
-  ** then set iDb to 1 to create the trigger in the temporary database.
-  ** If sqlite3SrcListLookup() returns 0, indicating the table does not
-  ** exist, the error is caught by the block below.
+  /* Argument pIdx must either point to a 'real' named index structure, 
+  ** or an index structure allocated on the stack by bestBtreeIndex() to
+  ** represent the rowid index that is part of every table.  */
+  assert( pIdx->zName || (pIdx->nColumn==1 && pIdx->aiColumn[0]==-1) );
+
+  /* Match terms of the ORDER BY clause against columns of
+  ** the index.
+  **
+  ** Note that indices have pIdx->nColumn regular columns plus
+  ** one additional column containing the rowid.  The rowid column
+  ** of the index is also allowed to match against the ORDER BY
+  ** clause.
   */
-  if( !pTableName || db->mallocFailed ){
-    goto trigger_cleanup;
-  }
-  pTab = sqlite3SrcListLookup(pParse, pTableName);
-  if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
-    iDb = 1;
-  }
+  for(i=j=0, pTerm=pOrderBy->a; j<nTerm && i<=pIdx->nColumn; i++){
+    Expr *pExpr;       /* The expression of the ORDER BY pTerm */
+    CollSeq *pColl;    /* The collating sequence of pExpr */
+    int termSortOrder; /* Sort order for this term */
+    int iColumn;       /* The i-th column of the index.  -1 for rowid */
+    int iSortOrder;    /* 1 for DESC, 0 for ASC on the i-th index term */
+    const char *zColl; /* Name of the collating sequence for i-th index term */
 
-  /* Ensure the table name matches database name and that the table exists */
-  if( db->mallocFailed ) goto trigger_cleanup;
-  assert( pTableName->nSrc==1 );
-  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) && 
-      sqlite3FixSrcList(&sFix, pTableName) ){
-    goto trigger_cleanup;
-  }
-  pTab = sqlite3SrcListLookup(pParse, pTableName);
-  if( !pTab ){
-    /* The table does not exist. */
-    goto trigger_cleanup;
-  }
-  if( IsVirtual(pTab) ){
-    sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
-    goto trigger_cleanup;
+    pExpr = pTerm->pExpr;
+    if( pExpr->op!=TK_COLUMN || pExpr->iTable!=base ){
+      /* Can not use an index sort on anything that is not a column in the
+      ** left-most table of the FROM clause */
+      break;
+    }
+    pColl = sqlite3ExprCollSeq(pParse, pExpr);
+    if( !pColl ){
+      pColl = db->pDfltColl;
+    }
+    if( pIdx->zName && i<pIdx->nColumn ){
+      iColumn = pIdx->aiColumn[i];
+      if( iColumn==pIdx->pTable->iPKey ){
+        iColumn = -1;
+      }
+      iSortOrder = pIdx->aSortOrder[i];
+      zColl = pIdx->azColl[i];
+    }else{
+      iColumn = -1;
+      iSortOrder = 0;
+      zColl = pColl->zName;
+    }
+    if( pExpr->iColumn!=iColumn || sqlite3StrICmp(pColl->zName, zColl) ){
+      /* Term j of the ORDER BY clause does not match column i of the index */
+      if( i<nEqCol ){
+        /* If an index column that is constrained by == fails to match an
+        ** ORDER BY term, that is OK.  Just ignore that column of the index
+        */
+        continue;
+      }else if( i==pIdx->nColumn ){
+        /* Index column i is the rowid.  All other terms match. */
+        break;
+      }else{
+        /* If an index column fails to match and is not constrained by ==
+        ** then the index cannot satisfy the ORDER BY constraint.
+        */
+        return 0;
+      }
+    }
+    assert( pIdx->aSortOrder!=0 || iColumn==-1 );
+    assert( pTerm->sortOrder==0 || pTerm->sortOrder==1 );
+    assert( iSortOrder==0 || iSortOrder==1 );
+    termSortOrder = iSortOrder ^ pTerm->sortOrder;
+    if( i>nEqCol ){
+      if( termSortOrder!=sortOrder ){
+        /* Indices can only be used if all ORDER BY terms past the
+        ** equality constraints are all either DESC or ASC. */
+        return 0;
+      }
+    }else{
+      sortOrder = termSortOrder;
+    }
+    j++;
+    pTerm++;
+    if( iColumn<0 && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
+      /* If the indexed column is the primary key and everything matches
+      ** so far and none of the ORDER BY terms to the right reference other
+      ** tables in the join, then we are assured that the index can be used 
+      ** to sort because the primary key is unique and so none of the other
+      ** columns will make any difference
+      */
+      j = nTerm;
+    }
   }
 
-  /* Check that the trigger name is not reserved and that no trigger of the
-  ** specified name exists */
-  zName = sqlite3NameFromToken(db, pName);
-  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
-    goto trigger_cleanup;
+  *pbRev = sortOrder!=0;
+  if( j>=nTerm ){
+    /* All terms of the ORDER BY clause are covered by this index so
+    ** this index can be used for sorting. */
+    return 1;
   }
-  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash), zName,strlen(zName)) ){
-    if( !noErr ){
-      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
-    }
-    goto trigger_cleanup;
+  if( pIdx->onError!=OE_None && i==pIdx->nColumn
+      && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
+    /* All terms of this index match some prefix of the ORDER BY clause
+    ** and the index is UNIQUE and no terms on the tail of the ORDER BY
+    ** clause reference other tables in a join.  If this is all true then
+    ** the order by clause is superfluous. */
+    return 1;
   }
+  return 0;
+}
 
-  /* Do not create a trigger on a system table */
-  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
-    sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
-    pParse->nErr++;
-    goto trigger_cleanup;
+/*
+** Prepare a crude estimate of the logarithm of the input value.
+** The results need not be exact.  This is only used for estimating
+** the total cost of performing operations with O(logN) or O(NlogN)
+** complexity.  Because N is just a guess, it is no great tragedy if
+** logN is a little off.
+*/
+static double estLog(double N){
+  double logN = 1;
+  double x = 10;
+  while( N>x ){
+    logN += 1;
+    x *= 10;
   }
+  return logN;
+}
 
-  /* INSTEAD of triggers are only for views and views only support INSTEAD
-  ** of triggers.
-  */
-  if( pTab->pSelect && tr_tm!=TK_INSTEAD ){
-    sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S", 
-        (tr_tm == TK_BEFORE)?"BEFORE":"AFTER", pTableName, 0);
-    goto trigger_cleanup;
+/*
+** Two routines for printing the content of an sqlite3_index_info
+** structure.  Used for testing and debugging only.  If neither
+** SQLITE_TEST or SQLITE_DEBUG are defined, then these routines
+** are no-ops.
+*/
+#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_DEBUG)
+static void TRACE_IDX_INPUTS(sqlite3_index_info *p){
+  int i;
+  if( !sqlite3WhereTrace ) return;
+  for(i=0; i<p->nConstraint; i++){
+    sqlite3DebugPrintf("  constraint[%d]: col=%d termid=%d op=%d usabled=%d\n",
+       i,
+       p->aConstraint[i].iColumn,
+       p->aConstraint[i].iTermOffset,
+       p->aConstraint[i].op,
+       p->aConstraint[i].usable);
   }
-  if( !pTab->pSelect && tr_tm==TK_INSTEAD ){
-    sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
-        " trigger on table: %S", pTableName, 0);
-    goto trigger_cleanup;
+  for(i=0; i<p->nOrderBy; i++){
+    sqlite3DebugPrintf("  orderby[%d]: col=%d desc=%d\n",
+       i,
+       p->aOrderBy[i].iColumn,
+       p->aOrderBy[i].desc);
   }
-  iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  {
-    int code = SQLITE_CREATE_TRIGGER;
-    const char *zDb = db->aDb[iTabDb].zName;
-    const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
-    if( iTabDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
-    if( sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig) ){
-      goto trigger_cleanup;
-    }
-    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb),0,zDb)){
-      goto trigger_cleanup;
-    }
+}
+static void TRACE_IDX_OUTPUTS(sqlite3_index_info *p){
+  int i;
+  if( !sqlite3WhereTrace ) return;
+  for(i=0; i<p->nConstraint; i++){
+    sqlite3DebugPrintf("  usage[%d]: argvIdx=%d omit=%d\n",
+       i,
+       p->aConstraintUsage[i].argvIndex,
+       p->aConstraintUsage[i].omit);
   }
+  sqlite3DebugPrintf("  idxNum=%d\n", p->idxNum);
+  sqlite3DebugPrintf("  idxStr=%s\n", p->idxStr);
+  sqlite3DebugPrintf("  orderByConsumed=%d\n", p->orderByConsumed);
+  sqlite3DebugPrintf("  estimatedCost=%g\n", p->estimatedCost);
+}
+#else
+#define TRACE_IDX_INPUTS(A)
+#define TRACE_IDX_OUTPUTS(A)
 #endif
 
-  /* INSTEAD OF triggers can only appear on views and BEFORE triggers
-  ** cannot appear on views.  So we might as well translate every
-  ** INSTEAD OF trigger into a BEFORE trigger.  It simplifies code
-  ** elsewhere.
-  */
-  if (tr_tm == TK_INSTEAD){
-    tr_tm = TK_BEFORE;
-  }
+/* 
+** Required because bestIndex() is called by bestOrClauseIndex() 
+*/
+static void bestIndex(
+    Parse*, WhereClause*, struct SrcList_item*, Bitmask, ExprList*, WhereCost*);
 
-  /* Build the Trigger object */
-  pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
-  if( pTrigger==0 ) goto trigger_cleanup;
-  pTrigger->name = zName;
-  zName = 0;
-  pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
-  pTrigger->pSchema = db->aDb[iDb].pSchema;
-  pTrigger->pTabSchema = pTab->pSchema;
-  pTrigger->op = op;
-  pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
-  pTrigger->pWhen = sqlite3ExprDup(db, pWhen);
-  pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
-  sqlite3TokenCopy(db, &pTrigger->nameToken,pName);
-  assert( pParse->pNewTrigger==0 );
-  pParse->pNewTrigger = pTrigger;
+/*
+** This routine attempts to find an scanning strategy that can be used 
+** to optimize an 'OR' expression that is part of a WHERE clause. 
+**
+** The table associated with FROM clause term pSrc may be either a
+** regular B-Tree table or a virtual table.
+*/
+static void bestOrClauseIndex(
+  Parse *pParse,              /* The parsing context */
+  WhereClause *pWC,           /* The WHERE clause */
+  struct SrcList_item *pSrc,  /* The FROM clause term to search */
+  Bitmask notReady,           /* Mask of cursors that are not available */
+  ExprList *pOrderBy,         /* The ORDER BY clause */
+  WhereCost *pCost            /* Lowest cost query plan */
+){
+#ifndef SQLITE_OMIT_OR_OPTIMIZATION
+  const int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
+  const Bitmask maskSrc = getMask(pWC->pMaskSet, iCur);  /* Bitmask for pSrc */
+  WhereTerm * const pWCEnd = &pWC->a[pWC->nTerm];        /* End of pWC->a[] */
+  WhereTerm *pTerm;                 /* A single term of the WHERE clause */
+
+  /* Search the WHERE clause terms for a usable WO_OR term. */
+  for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
+    if( pTerm->eOperator==WO_OR 
+     && ((pTerm->prereqAll & ~maskSrc) & notReady)==0
+     && (pTerm->u.pOrInfo->indexable & maskSrc)!=0 
+    ){
+      WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc;
+      WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm];
+      WhereTerm *pOrTerm;
+      int flags = WHERE_MULTI_OR;
+      double rTotal = 0;
+      double nRow = 0;
+      Bitmask used = 0;
+
+      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
+        WhereCost sTermCost;
+        WHERETRACE(("... Multi-index OR testing for term %d of %d....\n", 
+          (pOrTerm - pOrWC->a), (pTerm - pWC->a)
+        ));
+        if( pOrTerm->eOperator==WO_AND ){
+          WhereClause *pAndWC = &pOrTerm->u.pAndInfo->wc;
+          bestIndex(pParse, pAndWC, pSrc, notReady, 0, &sTermCost);
+        }else if( pOrTerm->leftCursor==iCur ){
+          WhereClause tempWC;
+          tempWC.pParse = pWC->pParse;
+          tempWC.pMaskSet = pWC->pMaskSet;
+          tempWC.op = TK_AND;
+          tempWC.a = pOrTerm;
+          tempWC.nTerm = 1;
+          bestIndex(pParse, &tempWC, pSrc, notReady, 0, &sTermCost);
+        }else{
+          continue;
+        }
+        rTotal += sTermCost.rCost;
+        nRow += sTermCost.nRow;
+        used |= sTermCost.used;
+        if( rTotal>=pCost->rCost ) break;
+      }
 
-trigger_cleanup:
-  sqlite3_free(zName);
-  sqlite3SrcListDelete(pTableName);
-  sqlite3IdListDelete(pColumns);
-  sqlite3ExprDelete(pWhen);
-  if( !pParse->pNewTrigger ){
-    sqlite3DeleteTrigger(pTrigger);
-  }else{
-    assert( pParse->pNewTrigger==pTrigger );
+      /* If there is an ORDER BY clause, increase the scan cost to account 
+      ** for the cost of the sort. */
+      if( pOrderBy!=0 ){
+        rTotal += nRow*estLog(nRow);
+        WHERETRACE(("... sorting increases OR cost to %.9g\n", rTotal));
+      }
+
+      /* If the cost of scanning using this OR term for optimization is
+      ** less than the current cost stored in pCost, replace the contents
+      ** of pCost. */
+      WHERETRACE(("... multi-index OR cost=%.9g nrow=%.9g\n", rTotal, nRow));
+      if( rTotal<pCost->rCost ){
+        pCost->rCost = rTotal;
+        pCost->nRow = nRow;
+        pCost->used = used;
+        pCost->plan.wsFlags = flags;
+        pCost->plan.u.pTerm = pTerm;
+      }
+    }
   }
+#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
 }
 
+#ifndef SQLITE_OMIT_VIRTUALTABLE
 /*
-** This routine is called after all of the trigger actions have been parsed
-** in order to complete the process of building the trigger.
+** Allocate and populate an sqlite3_index_info structure. It is the 
+** responsibility of the caller to eventually release the structure
+** by passing the pointer returned by this function to sqlite3_free().
 */
-SQLITE_PRIVATE void sqlite3FinishTrigger(
-  Parse *pParse,          /* Parser context */
-  TriggerStep *pStepList, /* The triggered program */
-  Token *pAll             /* Token that describes the complete CREATE TRIGGER */
+static sqlite3_index_info *allocateIndexInfo(
+  Parse *pParse, 
+  WhereClause *pWC,
+  struct SrcList_item *pSrc,
+  ExprList *pOrderBy
 ){
-  Trigger *pTrig = 0;     /* The trigger whose construction is finishing up */
-  sqlite3 *db = pParse->db;  /* The database */
-  DbFixer sFix;
-  int iDb;                   /* Database containing the trigger */
-
-  pTrig = pParse->pNewTrigger;
-  pParse->pNewTrigger = 0;
-  if( pParse->nErr || !pTrig ) goto triggerfinish_cleanup;
-  iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
-  pTrig->step_list = pStepList;
-  while( pStepList ){
-    pStepList->pTrig = pTrig;
-    pStepList = pStepList->pNext;
-  }
-  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &pTrig->nameToken) 
-          && sqlite3FixTriggerStep(&sFix, pTrig->step_list) ){
-    goto triggerfinish_cleanup;
-  }
+  int i, j;
+  int nTerm;
+  struct sqlite3_index_constraint *pIdxCons;
+  struct sqlite3_index_orderby *pIdxOrderBy;
+  struct sqlite3_index_constraint_usage *pUsage;
+  WhereTerm *pTerm;
+  int nOrderBy;
+  sqlite3_index_info *pIdxInfo;
 
-  /* if we are not initializing, and this trigger is not on a TEMP table, 
-  ** build the sqlite_master entry
-  */
-  if( !db->init.busy ){
-    Vdbe *v;
-    char *z;
+  WHERETRACE(("Recomputing index info for %s...\n", pSrc->pTab->zName));
 
-    /* Make an entry in the sqlite_master table */
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) goto triggerfinish_cleanup;
-    sqlite3BeginWriteOperation(pParse, 0, iDb);
-    z = sqlite3DbStrNDup(db, (char*)pAll->z, pAll->n);
-    sqlite3NestedParse(pParse,
-       "INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
-       db->aDb[iDb].zName, SCHEMA_TABLE(iDb), pTrig->name,
-       pTrig->table, z);
-    sqlite3_free(z);
-    sqlite3ChangeCookie(pParse, iDb);
-    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
-        db, "type='trigger' AND name='%q'", pTrig->name), P4_DYNAMIC
-    );
+  /* Count the number of possible WHERE clause constraints referring
+  ** to this virtual table */
+  for(i=nTerm=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
+    if( pTerm->leftCursor != pSrc->iCursor ) continue;
+    assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
+    testcase( pTerm->eOperator==WO_IN );
+    testcase( pTerm->eOperator==WO_ISNULL );
+    if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
+    nTerm++;
   }
 
-  if( db->init.busy ){
-    int n;
-    Table *pTab;
-    Trigger *pDel;
-    pDel = sqlite3HashInsert(&db->aDb[iDb].pSchema->trigHash, 
-                     pTrig->name, strlen(pTrig->name), pTrig);
-    if( pDel ){
-      assert( pDel==pTrig );
-      db->mallocFailed = 1;
-      goto triggerfinish_cleanup;
+  /* If the ORDER BY clause contains only columns in the current 
+  ** virtual table then allocate space for the aOrderBy part of
+  ** the sqlite3_index_info structure.
+  */
+  nOrderBy = 0;
+  if( pOrderBy ){
+    for(i=0; i<pOrderBy->nExpr; i++){
+      Expr *pExpr = pOrderBy->a[i].pExpr;
+      if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break;
+    }
+    if( i==pOrderBy->nExpr ){
+      nOrderBy = pOrderBy->nExpr;
     }
-    n = strlen(pTrig->table) + 1;
-    pTab = sqlite3HashFind(&pTrig->pTabSchema->tblHash, pTrig->table, n);
-    assert( pTab!=0 );
-    pTrig->pNext = pTab->pTrigger;
-    pTab->pTrigger = pTrig;
-    pTrig = 0;
   }
 
-triggerfinish_cleanup:
-  sqlite3DeleteTrigger(pTrig);
-  assert( !pParse->pNewTrigger );
-  sqlite3DeleteTriggerStep(pStepList);
-}
-
-/*
-** Make a copy of all components of the given trigger step.  This has
-** the effect of copying all Expr.token.z values into memory obtained
-** from sqlite3_malloc().  As initially created, the Expr.token.z values
-** all point to the input string that was fed to the parser.  But that
-** string is ephemeral - it will go away as soon as the sqlite3_exec()
-** call that started the parser exits.  This routine makes a persistent
-** copy of all the Expr.token.z strings so that the TriggerStep structure
-** will be valid even after the sqlite3_exec() call returns.
-*/
-static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
-  if( p->target.z ){
-    p->target.z = (u8*)sqlite3DbStrNDup(db, (char*)p->target.z, p->target.n);
-    p->target.dyn = 1;
-  }
-  if( p->pSelect ){
-    Select *pNew = sqlite3SelectDup(db, p->pSelect);
-    sqlite3SelectDelete(p->pSelect);
-    p->pSelect = pNew;
-  }
-  if( p->pWhere ){
-    Expr *pNew = sqlite3ExprDup(db, p->pWhere);
-    sqlite3ExprDelete(p->pWhere);
-    p->pWhere = pNew;
+  /* Allocate the sqlite3_index_info structure
+  */
+  pIdxInfo = sqlite3DbMallocZero(pParse->db, sizeof(*pIdxInfo)
+                           + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
+                           + sizeof(*pIdxOrderBy)*nOrderBy );
+  if( pIdxInfo==0 ){
+    sqlite3ErrorMsg(pParse, "out of memory");
+    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
+    return 0;
   }
-  if( p->pExprList ){
-    ExprList *pNew = sqlite3ExprListDup(db, p->pExprList);
-    sqlite3ExprListDelete(p->pExprList);
-    p->pExprList = pNew;
+
+  /* Initialize the structure.  The sqlite3_index_info structure contains
+  ** many fields that are declared "const" to prevent xBestIndex from
+  ** changing them.  We have to do some funky casting in order to
+  ** initialize those fields.
+  */
+  pIdxCons = (struct sqlite3_index_constraint*)&pIdxInfo[1];
+  pIdxOrderBy = (struct sqlite3_index_orderby*)&pIdxCons[nTerm];
+  pUsage = (struct sqlite3_index_constraint_usage*)&pIdxOrderBy[nOrderBy];
+  *(int*)&pIdxInfo->nConstraint = nTerm;
+  *(int*)&pIdxInfo->nOrderBy = nOrderBy;
+  *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint = pIdxCons;
+  *(struct sqlite3_index_orderby**)&pIdxInfo->aOrderBy = pIdxOrderBy;
+  *(struct sqlite3_index_constraint_usage**)&pIdxInfo->aConstraintUsage =
+                                                                   pUsage;
+
+  for(i=j=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
+    if( pTerm->leftCursor != pSrc->iCursor ) continue;
+    assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
+    testcase( pTerm->eOperator==WO_IN );
+    testcase( pTerm->eOperator==WO_ISNULL );
+    if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
+    pIdxCons[j].iColumn = pTerm->u.leftColumn;
+    pIdxCons[j].iTermOffset = i;
+    pIdxCons[j].op = (u8)pTerm->eOperator;
+    /* The direct assignment in the previous line is possible only because
+    ** the WO_ and SQLITE_INDEX_CONSTRAINT_ codes are identical.  The
+    ** following asserts verify this fact. */
+    assert( WO_EQ==SQLITE_INDEX_CONSTRAINT_EQ );
+    assert( WO_LT==SQLITE_INDEX_CONSTRAINT_LT );
+    assert( WO_LE==SQLITE_INDEX_CONSTRAINT_LE );
+    assert( WO_GT==SQLITE_INDEX_CONSTRAINT_GT );
+    assert( WO_GE==SQLITE_INDEX_CONSTRAINT_GE );
+    assert( WO_MATCH==SQLITE_INDEX_CONSTRAINT_MATCH );
+    assert( pTerm->eOperator & (WO_EQ|WO_LT|WO_LE|WO_GT|WO_GE|WO_MATCH) );
+    j++;
   }
-  if( p->pIdList ){
-    IdList *pNew = sqlite3IdListDup(db, p->pIdList);
-    sqlite3IdListDelete(p->pIdList);
-    p->pIdList = pNew;
+  for(i=0; i<nOrderBy; i++){
+    Expr *pExpr = pOrderBy->a[i].pExpr;
+    pIdxOrderBy[i].iColumn = pExpr->iColumn;
+    pIdxOrderBy[i].desc = pOrderBy->a[i].sortOrder;
   }
+
+  return pIdxInfo;
 }
 
 /*
-** Turn a SELECT statement (that the pSelect parameter points to) into
-** a trigger step.  Return a pointer to a TriggerStep structure.
+** The table object reference passed as the second argument to this function
+** must represent a virtual table. This function invokes the xBestIndex()
+** method of the virtual table with the sqlite3_index_info pointer passed
+** as the argument.
 **
-** The parser calls this routine when it finds a SELECT statement in
-** body of a TRIGGER.  
+** If an error occurs, pParse is populated with an error message and a
+** non-zero value is returned. Otherwise, 0 is returned and the output
+** part of the sqlite3_index_info structure is left populated.
+**
+** Whether or not an error is returned, it is the responsibility of the
+** caller to eventually free p->idxStr if p->needToFreeIdxStr indicates
+** that this is required.
 */
-SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
-  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
-  if( pTriggerStep==0 ) {
-    sqlite3SelectDelete(pSelect);
-    return 0;
+static int vtabBestIndex(Parse *pParse, Table *pTab, sqlite3_index_info *p){
+  sqlite3_vtab *pVtab = sqlite3GetVTable(pParse->db, pTab)->pVtab;
+  int i;
+  int rc;
+
+  (void)sqlite3SafetyOff(pParse->db);
+  WHERETRACE(("xBestIndex for %s\n", pTab->zName));
+  TRACE_IDX_INPUTS(p);
+  rc = pVtab->pModule->xBestIndex(pVtab, p);
+  TRACE_IDX_OUTPUTS(p);
+  (void)sqlite3SafetyOn(pParse->db);
+
+  if( rc!=SQLITE_OK ){
+    if( rc==SQLITE_NOMEM ){
+      pParse->db->mallocFailed = 1;
+    }else if( !pVtab->zErrMsg ){
+      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
+    }else{
+      sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
+    }
   }
+  sqlite3DbFree(pParse->db, pVtab->zErrMsg);
+  pVtab->zErrMsg = 0;
 
-  pTriggerStep->op = TK_SELECT;
-  pTriggerStep->pSelect = pSelect;
-  pTriggerStep->orconf = OE_Default;
-  sqlitePersistTriggerStep(db, pTriggerStep);
+  for(i=0; i<p->nConstraint; i++){
+    if( !p->aConstraint[i].usable && p->aConstraintUsage[i].argvIndex>0 ){
+      sqlite3ErrorMsg(pParse, 
+          "table %s: xBestIndex returned an invalid plan", pTab->zName);
+    }
+  }
 
-  return pTriggerStep;
+  return pParse->nErr;
 }
 
+
 /*
-** Build a trigger step out of an INSERT statement.  Return a pointer
-** to the new trigger step.
+** Compute the best index for a virtual table.
 **
-** The parser calls this routine when it sees an INSERT inside the
-** body of a trigger.
+** The best index is computed by the xBestIndex method of the virtual
+** table module.  This routine is really just a wrapper that sets up
+** the sqlite3_index_info structure that is used to communicate with
+** xBestIndex.
+**
+** In a join, this routine might be called multiple times for the
+** same virtual table.  The sqlite3_index_info structure is created
+** and initialized on the first invocation and reused on all subsequent
+** invocations.  The sqlite3_index_info structure is also used when
+** code is generated to access the virtual table.  The whereInfoDelete() 
+** routine takes care of freeing the sqlite3_index_info structure after
+** everybody has finished with it.
 */
-SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(
-  sqlite3 *db,        /* The database connection */
-  Token *pTableName,  /* Name of the table into which we insert */
-  IdList *pColumn,    /* List of columns in pTableName to insert into */
-  ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
-  Select *pSelect,    /* A SELECT statement that supplies values */
-  int orconf          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
+static void bestVirtualIndex(
+  Parse *pParse,                  /* The parsing context */
+  WhereClause *pWC,               /* The WHERE clause */
+  struct SrcList_item *pSrc,      /* The FROM clause term to search */
+  Bitmask notReady,               /* Mask of cursors that are not available */
+  ExprList *pOrderBy,             /* The order by clause */
+  WhereCost *pCost,               /* Lowest cost query plan */
+  sqlite3_index_info **ppIdxInfo  /* Index information passed to xBestIndex */
 ){
-  TriggerStep *pTriggerStep;
+  Table *pTab = pSrc->pTab;
+  sqlite3_index_info *pIdxInfo;
+  struct sqlite3_index_constraint *pIdxCons;
+  struct sqlite3_index_constraint_usage *pUsage;
+  WhereTerm *pTerm;
+  int i, j;
+  int nOrderBy;
 
-  assert(pEList == 0 || pSelect == 0);
-  assert(pEList != 0 || pSelect != 0 || db->mallocFailed);
+  /* Make sure wsFlags is initialized to some sane value. Otherwise, if the 
+  ** malloc in allocateIndexInfo() fails and this function returns leaving
+  ** wsFlags in an uninitialized state, the caller may behave unpredictably.
+  */
+  memset(pCost, 0, sizeof(*pCost));
+  pCost->plan.wsFlags = WHERE_VIRTUALTABLE;
 
-  pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
-  if( pTriggerStep ){
-    pTriggerStep->op = TK_INSERT;
-    pTriggerStep->pSelect = pSelect;
-    pTriggerStep->target  = *pTableName;
-    pTriggerStep->pIdList = pColumn;
-    pTriggerStep->pExprList = pEList;
-    pTriggerStep->orconf = orconf;
-    sqlitePersistTriggerStep(db, pTriggerStep);
-  }else{
-    sqlite3IdListDelete(pColumn);
-    sqlite3ExprListDelete(pEList);
-    sqlite3SelectDelete(pSelect);
+  /* If the sqlite3_index_info structure has not been previously
+  ** allocated and initialized, then allocate and initialize it now.
+  */
+  pIdxInfo = *ppIdxInfo;
+  if( pIdxInfo==0 ){
+    *ppIdxInfo = pIdxInfo = allocateIndexInfo(pParse, pWC, pSrc, pOrderBy);
+  }
+  if( pIdxInfo==0 ){
+    return;
   }
 
-  return pTriggerStep;
-}
+  /* At this point, the sqlite3_index_info structure that pIdxInfo points
+  ** to will have been initialized, either during the current invocation or
+  ** during some prior invocation.  Now we just have to customize the
+  ** details of pIdxInfo for the current invocation and pass it to
+  ** xBestIndex.
+  */
 
-/*
-** Construct a trigger step that implements an UPDATE statement and return
-** a pointer to that trigger step.  The parser calls this routine when it
-** sees an UPDATE statement inside the body of a CREATE TRIGGER.
-*/
-SQLITE_PRIVATE TriggerStep *sqlite3TriggerUpdateStep(
-  sqlite3 *db,         /* The database connection */
-  Token *pTableName,   /* Name of the table to be updated */
-  ExprList *pEList,    /* The SET clause: list of column and new values */
-  Expr *pWhere,        /* The WHERE clause */
-  int orconf           /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
-){
-  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
-  if( pTriggerStep==0 ){
-     sqlite3ExprListDelete(pEList);
-     sqlite3ExprDelete(pWhere);
-     return 0;
+  /* The module name must be defined. Also, by this point there must
+  ** be a pointer to an sqlite3_vtab structure. Otherwise
+  ** sqlite3ViewGetColumnNames() would have picked up the error. 
+  */
+  assert( pTab->azModuleArg && pTab->azModuleArg[0] );
+  assert( sqlite3GetVTable(pParse->db, pTab) );
+
+  /* Set the aConstraint[].usable fields and initialize all 
+  ** output variables to zero.
+  **
+  ** aConstraint[].usable is true for constraints where the right-hand
+  ** side contains only references to tables to the left of the current
+  ** table.  In other words, if the constraint is of the form:
+  **
+  **           column = expr
+  **
+  ** and we are evaluating a join, then the constraint on column is 
+  ** only valid if all tables referenced in expr occur to the left
+  ** of the table containing column.
+  **
+  ** The aConstraints[] array contains entries for all constraints
+  ** on the current table.  That way we only have to compute it once
+  ** even though we might try to pick the best index multiple times.
+  ** For each attempt at picking an index, the order of tables in the
+  ** join might be different so we have to recompute the usable flag
+  ** each time.
+  */
+  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
+  pUsage = pIdxInfo->aConstraintUsage;
+  for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
+    j = pIdxCons->iTermOffset;
+    pTerm = &pWC->a[j];
+    pIdxCons->usable = (pTerm->prereqRight&notReady) ? 0 : 1;
+  }
+  memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
+  if( pIdxInfo->needToFreeIdxStr ){
+    sqlite3_free(pIdxInfo->idxStr);
+  }
+  pIdxInfo->idxStr = 0;
+  pIdxInfo->idxNum = 0;
+  pIdxInfo->needToFreeIdxStr = 0;
+  pIdxInfo->orderByConsumed = 0;
+  /* ((double)2) In case of SQLITE_OMIT_FLOATING_POINT... */
+  pIdxInfo->estimatedCost = SQLITE_BIG_DBL / ((double)2);
+  nOrderBy = pIdxInfo->nOrderBy;
+  if( !pOrderBy ){
+    pIdxInfo->nOrderBy = 0;
   }
 
-  pTriggerStep->op = TK_UPDATE;
-  pTriggerStep->target  = *pTableName;
-  pTriggerStep->pExprList = pEList;
-  pTriggerStep->pWhere = pWhere;
-  pTriggerStep->orconf = orconf;
-  sqlitePersistTriggerStep(db, pTriggerStep);
+  if( vtabBestIndex(pParse, pTab, pIdxInfo) ){
+    return;
+  }
 
-  return pTriggerStep;
+  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
+  for(i=0; i<pIdxInfo->nConstraint; i++){
+    if( pUsage[i].argvIndex>0 ){
+      pCost->used |= pWC->a[pIdxCons[i].iTermOffset].prereqRight;
+    }
+  }
+
+  /* The cost is not allowed to be larger than SQLITE_BIG_DBL (the
+  ** inital value of lowestCost in this loop. If it is, then the
+  ** (cost<lowestCost) test below will never be true.
+  ** 
+  ** Use "(double)2" instead of "2.0" in case OMIT_FLOATING_POINT 
+  ** is defined.
+  */
+  if( (SQLITE_BIG_DBL/((double)2))<pIdxInfo->estimatedCost ){
+    pCost->rCost = (SQLITE_BIG_DBL/((double)2));
+  }else{
+    pCost->rCost = pIdxInfo->estimatedCost;
+  }
+  pCost->plan.u.pVtabIdx = pIdxInfo;
+  if( pIdxInfo->orderByConsumed ){
+    pCost->plan.wsFlags |= WHERE_ORDERBY;
+  }
+  pCost->plan.nEq = 0;
+  pIdxInfo->nOrderBy = nOrderBy;
+
+  /* Try to find a more efficient access pattern by using multiple indexes
+  ** to optimize an OR expression within the WHERE clause. 
+  */
+  bestOrClauseIndex(pParse, pWC, pSrc, notReady, pOrderBy, pCost);
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
 /*
-** Construct a trigger step that implements a DELETE statement and return
-** a pointer to that trigger step.  The parser calls this routine when it
-** sees a DELETE statement inside the body of a CREATE TRIGGER.
-*/
-SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(
-  sqlite3 *db,            /* Database connection */
-  Token *pTableName,      /* The table from which rows are deleted */
-  Expr *pWhere            /* The WHERE clause */
+** Argument pIdx is a pointer to an index structure that has an array of
+** SQLITE_INDEX_SAMPLES evenly spaced samples of the first indexed column
+** stored in Index.aSample. The domain of values stored in said column
+** may be thought of as divided into (SQLITE_INDEX_SAMPLES+1) regions.
+** Region 0 contains all values smaller than the first sample value. Region
+** 1 contains values larger than or equal to the value of the first sample,
+** but smaller than the value of the second. And so on.
+**
+** If successful, this function determines which of the regions value 
+** pVal lies in, sets *piRegion to the region index (a value between 0
+** and SQLITE_INDEX_SAMPLES+1, inclusive) and returns SQLITE_OK.
+** Or, if an OOM occurs while converting text values between encodings,
+** SQLITE_NOMEM is returned and *piRegion is undefined.
+*/
+#ifdef SQLITE_ENABLE_STAT2
+static int whereRangeRegion(
+  Parse *pParse,              /* Database connection */
+  Index *pIdx,                /* Index to consider domain of */
+  sqlite3_value *pVal,        /* Value to consider */
+  int *piRegion               /* OUT: Region of domain in which value lies */
 ){
-  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
-  if( pTriggerStep==0 ){
-    sqlite3ExprDelete(pWhere);
-    return 0;
-  }
+  if( ALWAYS(pVal) ){
+    IndexSample *aSample = pIdx->aSample;
+    int i = 0;
+    int eType = sqlite3_value_type(pVal);
 
-  pTriggerStep->op = TK_DELETE;
-  pTriggerStep->target  = *pTableName;
-  pTriggerStep->pWhere = pWhere;
-  pTriggerStep->orconf = OE_Default;
-  sqlitePersistTriggerStep(db, pTriggerStep);
+    if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
+      double r = sqlite3_value_double(pVal);
+      for(i=0; i<SQLITE_INDEX_SAMPLES; i++){
+        if( aSample[i].eType==SQLITE_NULL ) continue;
+        if( aSample[i].eType>=SQLITE_TEXT || aSample[i].u.r>r ) break;
+      }
+    }else{ 
+      sqlite3 *db = pParse->db;
+      CollSeq *pColl;
+      const u8 *z;
+      int n;
 
-  return pTriggerStep;
-}
+      /* pVal comes from sqlite3ValueFromExpr() so the type cannot be NULL */
+      assert( eType==SQLITE_TEXT || eType==SQLITE_BLOB );
 
-/* 
-** Recursively delete a Trigger structure
-*/
-SQLITE_PRIVATE void sqlite3DeleteTrigger(Trigger *pTrigger){
-  if( pTrigger==0 ) return;
-  sqlite3DeleteTriggerStep(pTrigger->step_list);
-  sqlite3_free(pTrigger->name);
-  sqlite3_free(pTrigger->table);
-  sqlite3ExprDelete(pTrigger->pWhen);
-  sqlite3IdListDelete(pTrigger->pColumns);
-  if( pTrigger->nameToken.dyn ) sqlite3_free((char*)pTrigger->nameToken.z);
-  sqlite3_free(pTrigger);
+      if( eType==SQLITE_BLOB ){
+        z = (const u8 *)sqlite3_value_blob(pVal);
+        pColl = db->pDfltColl;
+        assert( pColl->enc==SQLITE_UTF8 );
+      }else{
+        pColl = sqlite3GetCollSeq(db, SQLITE_UTF8, 0, *pIdx->azColl);
+        if( pColl==0 ){
+          sqlite3ErrorMsg(pParse, "no such collation sequence: %s",
+                          *pIdx->azColl);
+          return SQLITE_ERROR;
+        }
+        z = (const u8 *)sqlite3ValueText(pVal, pColl->enc);
+        if( !z ){
+          return SQLITE_NOMEM;
+        }
+        assert( z && pColl && pColl->xCmp );
+      }
+      n = sqlite3ValueBytes(pVal, pColl->enc);
+
+      for(i=0; i<SQLITE_INDEX_SAMPLES; i++){
+        int r;
+        int eSampletype = aSample[i].eType;
+        if( eSampletype==SQLITE_NULL || eSampletype<eType ) continue;
+        if( (eSampletype!=eType) ) break;
+#ifndef SQLITE_OMIT_UTF16
+        if( pColl->enc!=SQLITE_UTF8 ){
+          int nSample;
+          char *zSample = sqlite3Utf8to16(
+              db, pColl->enc, aSample[i].u.z, aSample[i].nByte, &nSample
+          );
+          if( !zSample ){
+            assert( db->mallocFailed );
+            return SQLITE_NOMEM;
+          }
+          r = pColl->xCmp(pColl->pUser, nSample, zSample, n, z);
+          sqlite3DbFree(db, zSample);
+        }else
+#endif
+        {
+          r = pColl->xCmp(pColl->pUser, aSample[i].nByte, aSample[i].u.z, n, z);
+        }
+        if( r>0 ) break;
+      }
+    }
+
+    assert( i>=0 && i<=SQLITE_INDEX_SAMPLES );
+    *piRegion = i;
+  }
+  return SQLITE_OK;
 }
+#endif   /* #ifdef SQLITE_ENABLE_STAT2 */
 
 /*
-** This function is called to drop a trigger from the database schema. 
+** This function is used to estimate the number of rows that will be visited
+** by scanning an index for a range of values. The range may have an upper
+** bound, a lower bound, or both. The WHERE clause terms that set the upper
+** and lower bounds are represented by pLower and pUpper respectively. For
+** example, assuming that index p is on t1(a):
 **
-** This may be called directly from the parser and therefore identifies
-** the trigger by name.  The sqlite3DropTriggerPtr() routine does the
-** same job as this routine except it takes a pointer to the trigger
-** instead of the trigger name.
-**/
-SQLITE_PRIVATE void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr){
-  Trigger *pTrigger = 0;
-  int i;
-  const char *zDb;
-  const char *zName;
-  int nName;
+**   ... FROM t1 WHERE a > ? AND a < ? ...
+**                    |_____|   |_____|
+**                       |         |
+**                     pLower    pUpper
+**
+** If either of the upper or lower bound is not present, then NULL is passed in
+** place of the corresponding WhereTerm.
+**
+** The nEq parameter is passed the index of the index column subject to the
+** range constraint. Or, equivalently, the number of equality constraints
+** optimized by the proposed index scan. For example, assuming index p is
+** on t1(a, b), and the SQL query is:
+**
+**   ... FROM t1 WHERE a = ? AND b > ? AND b < ? ...
+**
+** then nEq should be passed the value 1 (as the range restricted column,
+** b, is the second left-most column of the index). Or, if the query is:
+**
+**   ... FROM t1 WHERE a > ? AND a < ? ...
+**
+** then nEq should be passed 0.
+**
+** The returned value is an integer between 1 and 100, inclusive. A return
+** value of 1 indicates that the proposed range scan is expected to visit
+** approximately 1/100th (1%) of the rows selected by the nEq equality
+** constraints (if any). A return value of 100 indicates that it is expected
+** that the range scan will visit every row (100%) selected by the equality
+** constraints.
+**
+** In the absence of sqlite_stat2 ANALYZE data, each range inequality
+** reduces the search space by 2/3rds.  Hence a single constraint (x>?)
+** results in a return of 33 and a range constraint (x>? AND x<?) results
+** in a return of 11.
+*/
+static int whereRangeScanEst(
+  Parse *pParse,       /* Parsing & code generating context */
+  Index *p,            /* The index containing the range-compared column; "x" */
+  int nEq,             /* index into p->aCol[] of the range-compared column */
+  WhereTerm *pLower,   /* Lower bound on the range. ex: "x>123" Might be NULL */
+  WhereTerm *pUpper,   /* Upper bound on the range. ex: "x<455" Might be NULL */
+  int *piEst           /* OUT: Return value */
+){
+  int rc = SQLITE_OK;
+
+#ifdef SQLITE_ENABLE_STAT2
   sqlite3 *db = pParse->db;
+  sqlite3_value *pLowerVal = 0;
+  sqlite3_value *pUpperVal = 0;
+
+  if( nEq==0 && p->aSample ){
+    int iEst;
+    int iLower = 0;
+    int iUpper = SQLITE_INDEX_SAMPLES;
+    u8 aff = p->pTable->aCol[0].affinity;
+
+    if( pLower ){
+      Expr *pExpr = pLower->pExpr->pRight;
+      rc = sqlite3ValueFromExpr(db, pExpr, SQLITE_UTF8, aff, &pLowerVal);
+    }
+    if( rc==SQLITE_OK && pUpper ){
+      Expr *pExpr = pUpper->pExpr->pRight;
+      rc = sqlite3ValueFromExpr(db, pExpr, SQLITE_UTF8, aff, &pUpperVal);
+    }
+
+    if( rc!=SQLITE_OK || (pLowerVal==0 && pUpperVal==0) ){
+      sqlite3ValueFree(pLowerVal);
+      sqlite3ValueFree(pUpperVal);
+      goto range_est_fallback;
+    }else if( pLowerVal==0 ){
+      rc = whereRangeRegion(pParse, p, pUpperVal, &iUpper);
+      if( pLower ) iLower = iUpper/2;
+    }else if( pUpperVal==0 ){
+      rc = whereRangeRegion(pParse, p, pLowerVal, &iLower);
+      if( pUpper ) iUpper = (iLower + SQLITE_INDEX_SAMPLES + 1)/2;
+    }else{
+      rc = whereRangeRegion(pParse, p, pUpperVal, &iUpper);
+      if( rc==SQLITE_OK ){
+        rc = whereRangeRegion(pParse, p, pLowerVal, &iLower);
+      }
+    }
 
-  if( db->mallocFailed ) goto drop_trigger_cleanup;
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
-    goto drop_trigger_cleanup;
-  }
+    iEst = iUpper - iLower;
+    testcase( iEst==SQLITE_INDEX_SAMPLES );
+    assert( iEst<=SQLITE_INDEX_SAMPLES );
+    if( iEst<1 ){
+      iEst = 1;
+    }
 
-  assert( pName->nSrc==1 );
-  zDb = pName->a[0].zDatabase;
-  zName = pName->a[0].zName;
-  nName = strlen(zName);
-  for(i=OMIT_TEMPDB; i<db->nDb; i++){
-    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
-    if( zDb && sqlite3StrICmp(db->aDb[j].zName, zDb) ) continue;
-    pTrigger = sqlite3HashFind(&(db->aDb[j].pSchema->trigHash), zName, nName);
-    if( pTrigger ) break;
+    sqlite3ValueFree(pLowerVal);
+    sqlite3ValueFree(pUpperVal);
+    *piEst = (iEst * 100)/SQLITE_INDEX_SAMPLES;
+    return rc;
   }
-  if( !pTrigger ){
-    if( !noErr ){
-      sqlite3ErrorMsg(pParse, "no such trigger: %S", pName, 0);
-    }
-    goto drop_trigger_cleanup;
+range_est_fallback:
+#else
+  UNUSED_PARAMETER(pParse);
+  UNUSED_PARAMETER(p);
+  UNUSED_PARAMETER(nEq);
+#endif
+  assert( pLower || pUpper );
+  if( pLower && pUpper ){
+    *piEst = 11;
+  }else{
+    *piEst = 33;
   }
-  sqlite3DropTriggerPtr(pParse, pTrigger);
-
-drop_trigger_cleanup:
-  sqlite3SrcListDelete(pName);
-}
-
-/*
-** Return a pointer to the Table structure for the table that a trigger
-** is set on.
-*/
-static Table *tableOfTrigger(Trigger *pTrigger){
-  int n = strlen(pTrigger->table) + 1;
-  return sqlite3HashFind(&pTrigger->pTabSchema->tblHash, pTrigger->table, n);
+  return rc;
 }
 
 
 /*
-** Drop a trigger given a pointer to that trigger. 
+** Find the query plan for accessing a particular table.  Write the
+** best query plan and its cost into the WhereCost object supplied as the
+** last parameter.
+**
+** The lowest cost plan wins.  The cost is an estimate of the amount of
+** CPU and disk I/O need to process the request using the selected plan.
+** Factors that influence cost include:
+**
+**    *  The estimated number of rows that will be retrieved.  (The
+**       fewer the better.)
+**
+**    *  Whether or not sorting must occur.
+**
+**    *  Whether or not there must be separate lookups in the
+**       index and in the main table.
+**
+** If there was an INDEXED BY clause (pSrc->pIndex) attached to the table in
+** the SQL statement, then this function only considers plans using the 
+** named index. If no such plan is found, then the returned cost is
+** SQLITE_BIG_DBL. If a plan is found that uses the named index, 
+** then the cost is calculated in the usual way.
+**
+** If a NOT INDEXED clause (pSrc->notIndexed!=0) was attached to the table 
+** in the SELECT statement, then no indexes are considered. However, the 
+** selected plan may still take advantage of the tables built-in rowid
+** index.
 */
-SQLITE_PRIVATE void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
-  Table   *pTable;
-  Vdbe *v;
-  sqlite3 *db = pParse->db;
-  int iDb;
+static void bestBtreeIndex(
+  Parse *pParse,              /* The parsing context */
+  WhereClause *pWC,           /* The WHERE clause */
+  struct SrcList_item *pSrc,  /* The FROM clause term to search */
+  Bitmask notReady,           /* Mask of cursors that are not available */
+  ExprList *pOrderBy,         /* The ORDER BY clause */
+  WhereCost *pCost            /* Lowest cost query plan */
+){
+  int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
+  Index *pProbe;              /* An index we are evaluating */
+  Index *pIdx;                /* Copy of pProbe, or zero for IPK index */
+  int eqTermMask;             /* Current mask of valid equality operators */
+  int idxEqTermMask;          /* Index mask of valid equality operators */
+  Index sPk;                  /* A fake index object for the primary key */
+  unsigned int aiRowEstPk[2]; /* The aiRowEst[] value for the sPk index */
+  int aiColumnPk = -1;        /* The aColumn[] value for the sPk index */
+  int wsFlagMask;             /* Allowed flags in pCost->plan.wsFlag */
+
+  /* Initialize the cost to a worst-case value */
+  memset(pCost, 0, sizeof(*pCost));
+  pCost->rCost = SQLITE_BIG_DBL;
 
-  iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
-  assert( iDb>=0 && iDb<db->nDb );
-  pTable = tableOfTrigger(pTrigger);
-  assert( pTable );
-  assert( pTable->pSchema==pTrigger->pSchema || iDb==1 );
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  {
-    int code = SQLITE_DROP_TRIGGER;
-    const char *zDb = db->aDb[iDb].zName;
-    const char *zTab = SCHEMA_TABLE(iDb);
-    if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
-    if( sqlite3AuthCheck(pParse, code, pTrigger->name, pTable->zName, zDb) ||
-      sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
-      return;
+  /* If the pSrc table is the right table of a LEFT JOIN then we may not
+  ** use an index to satisfy IS NULL constraints on that table.  This is
+  ** because columns might end up being NULL if the table does not match -
+  ** a circumstance which the index cannot help us discover.  Ticket #2177.
+  */
+  if( pSrc->jointype & JT_LEFT ){
+    idxEqTermMask = WO_EQ|WO_IN;
+  }else{
+    idxEqTermMask = WO_EQ|WO_IN|WO_ISNULL;
+  }
+
+  if( pSrc->pIndex ){
+    /* An INDEXED BY clause specifies a particular index to use */
+    pIdx = pProbe = pSrc->pIndex;
+    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
+    eqTermMask = idxEqTermMask;
+  }else{
+    /* There is no INDEXED BY clause.  Create a fake Index object to
+    ** represent the primary key */
+    Index *pFirst;                /* Any other index on the table */
+    memset(&sPk, 0, sizeof(Index));
+    sPk.nColumn = 1;
+    sPk.aiColumn = &aiColumnPk;
+    sPk.aiRowEst = aiRowEstPk;
+    aiRowEstPk[1] = 1;
+    sPk.onError = OE_Replace;
+    sPk.pTable = pSrc->pTab;
+    pFirst = pSrc->pTab->pIndex;
+    if( pSrc->notIndexed==0 ){
+      sPk.pNext = pFirst;
+    }
+    /* The aiRowEstPk[0] is an estimate of the total number of rows in the
+    ** table.  Get this information from the ANALYZE information if it is
+    ** available.  If not available, assume the table 1 million rows in size.
+    */
+    if( pFirst ){
+      assert( pFirst->aiRowEst!=0 ); /* Allocated together with pFirst */
+      aiRowEstPk[0] = pFirst->aiRowEst[0];
+    }else{
+      aiRowEstPk[0] = 1000000;
     }
+    pProbe = &sPk;
+    wsFlagMask = ~(
+        WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
+    );
+    eqTermMask = WO_EQ|WO_IN;
+    pIdx = 0;
   }
-#endif
 
-  /* Generate code to destroy the database record of the trigger.
+  /* Loop over all indices looking for the best one to use
   */
-  assert( pTable!=0 );
-  if( (v = sqlite3GetVdbe(pParse))!=0 ){
-    int base;
-    static const VdbeOpList dropTrigger[] = {
-      { OP_Rewind,     0, ADDR(9),  0},
-      { OP_String8,    0, 1,        0}, /* 1 */
-      { OP_Column,     0, 1,        2},
-      { OP_Ne,         2, ADDR(8),  1},
-      { OP_String8,    0, 1,        0}, /* 4: "trigger" */
-      { OP_Column,     0, 0,        2},
-      { OP_Ne,         2, ADDR(8),  1},
-      { OP_Delete,     0, 0,        0},
-      { OP_Next,       0, ADDR(1),  0}, /* 8 */
-    };
+  for(; pProbe; pIdx=pProbe=pProbe->pNext){
+    const unsigned int * const aiRowEst = pProbe->aiRowEst;
+    double cost;                /* Cost of using pProbe */
+    double nRow;                /* Estimated number of rows in result set */
+    int rev;                    /* True to scan in reverse order */
+    int wsFlags = 0;
+    Bitmask used = 0;
 
-    sqlite3BeginWriteOperation(pParse, 0, iDb);
-    sqlite3OpenMasterTable(pParse, iDb);
-    base = sqlite3VdbeAddOpList(v,  ArraySize(dropTrigger), dropTrigger);
-    sqlite3VdbeChangeP4(v, base+1, pTrigger->name, 0);
-    sqlite3VdbeChangeP4(v, base+4, "trigger", P4_STATIC);
-    sqlite3ChangeCookie(pParse, iDb);
-    sqlite3VdbeAddOp2(v, OP_Close, 0, 0);
-    sqlite3VdbeAddOp4(v, OP_DropTrigger, iDb, 0, 0, pTrigger->name, 0);
-  }
-}
+    /* The following variables are populated based on the properties of
+    ** scan being evaluated. They are then used to determine the expected
+    ** cost and number of rows returned.
+    **
+    **  nEq: 
+    **    Number of equality terms that can be implemented using the index.
+    **
+    **  nInMul:  
+    **    The "in-multiplier". This is an estimate of how many seek operations 
+    **    SQLite must perform on the index in question. For example, if the 
+    **    WHERE clause is:
+    **
+    **      WHERE a IN (1, 2, 3) AND b IN (4, 5, 6)
+    **
+    **    SQLite must perform 9 lookups on an index on (a, b), so nInMul is 
+    **    set to 9. Given the same schema and either of the following WHERE 
+    **    clauses:
+    **
+    **      WHERE a =  1
+    **      WHERE a >= 2
+    **
+    **    nInMul is set to 1.
+    **
+    **    If there exists a WHERE term of the form "x IN (SELECT ...)", then 
+    **    the sub-select is assumed to return 25 rows for the purposes of 
+    **    determining nInMul.
+    **
+    **  bInEst:  
+    **    Set to true if there was at least one "x IN (SELECT ...)" term used 
+    **    in determining the value of nInMul.
+    **
+    **  nBound:
+    **    An estimate on the amount of the table that must be searched.  A
+    **    value of 100 means the entire table is searched.  Range constraints
+    **    might reduce this to a value less than 100 to indicate that only
+    **    a fraction of the table needs searching.  In the absence of
+    **    sqlite_stat2 ANALYZE data, a single inequality reduces the search
+    **    space to 1/3rd its original size.  So an x>? constraint reduces
+    **    nBound to 33.  Two constraints (x>? AND x<?) reduce nBound to 11.
+    **
+    **  bSort:   
+    **    Boolean. True if there is an ORDER BY clause that will require an 
+    **    external sort (i.e. scanning the index being evaluated will not 
+    **    correctly order records).
+    **
+    **  bLookup: 
+    **    Boolean. True if for each index entry visited a lookup on the 
+    **    corresponding table b-tree is required. This is always false 
+    **    for the rowid index. For other indexes, it is true unless all the 
+    **    columns of the table used by the SELECT statement are present in 
+    **    the index (such an index is sometimes described as a covering index).
+    **    For example, given the index on (a, b), the second of the following 
+    **    two queries requires table b-tree lookups, but the first does not.
+    **
+    **             SELECT a, b    FROM tbl WHERE a = 1;
+    **             SELECT a, b, c FROM tbl WHERE a = 1;
+    */
+    int nEq;
+    int bInEst = 0;
+    int nInMul = 1;
+    int nBound = 100;
+    int bSort = 0;
+    int bLookup = 0;
+
+    /* Determine the values of nEq and nInMul */
+    for(nEq=0; nEq<pProbe->nColumn; nEq++){
+      WhereTerm *pTerm;           /* A single term of the WHERE clause */
+      int j = pProbe->aiColumn[nEq];
+      pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pIdx);
+      if( pTerm==0 ) break;
+      wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ);
+      if( pTerm->eOperator & WO_IN ){
+        Expr *pExpr = pTerm->pExpr;
+        wsFlags |= WHERE_COLUMN_IN;
+        if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+          nInMul *= 25;
+          bInEst = 1;
+        }else if( pExpr->x.pList ){
+          nInMul *= pExpr->x.pList->nExpr + 1;
+        }
+      }else if( pTerm->eOperator & WO_ISNULL ){
+        wsFlags |= WHERE_COLUMN_NULL;
+      }
+      used |= pTerm->prereqRight;
+    }
 
-/*
-** Remove a trigger from the hash tables of the sqlite* pointer.
-*/
-SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const char *zName){
-  Trigger *pTrigger;
-  int nName = strlen(zName);
-  pTrigger = sqlite3HashInsert(&(db->aDb[iDb].pSchema->trigHash),
-                               zName, nName, 0);
-  if( pTrigger ){
-    Table *pTable = tableOfTrigger(pTrigger);
-    assert( pTable!=0 );
-    if( pTable->pTrigger == pTrigger ){
-      pTable->pTrigger = pTrigger->pNext;
-    }else{
-      Trigger *cc = pTable->pTrigger;
-      while( cc ){ 
-        if( cc->pNext == pTrigger ){
-          cc->pNext = cc->pNext->pNext;
-          break;
+    /* Determine the value of nBound. */
+    if( nEq<pProbe->nColumn ){
+      int j = pProbe->aiColumn[nEq];
+      if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pIdx) ){
+        WhereTerm *pTop = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pIdx);
+        WhereTerm *pBtm = findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pIdx);
+        whereRangeScanEst(pParse, pProbe, nEq, pBtm, pTop, &nBound);
+        if( pTop ){
+          wsFlags |= WHERE_TOP_LIMIT;
+          used |= pTop->prereqRight;
+        }
+        if( pBtm ){
+          wsFlags |= WHERE_BTM_LIMIT;
+          used |= pBtm->prereqRight;
+        }
+        wsFlags |= (WHERE_COLUMN_RANGE|WHERE_ROWID_RANGE);
+      }
+    }else if( pProbe->onError!=OE_None ){
+      testcase( wsFlags & WHERE_COLUMN_IN );
+      testcase( wsFlags & WHERE_COLUMN_NULL );
+      if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){
+        wsFlags |= WHERE_UNIQUE;
+      }
+    }
+
+    /* If there is an ORDER BY clause and the index being considered will
+    ** naturally scan rows in the required order, set the appropriate flags
+    ** in wsFlags. Otherwise, if there is an ORDER BY clause but the index
+    ** will scan rows in a different order, set the bSort variable.  */
+    if( pOrderBy ){
+      if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0
+        && isSortingIndex(pParse,pWC->pMaskSet,pProbe,iCur,pOrderBy,nEq,&rev)
+      ){
+        wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_ORDERBY;
+        wsFlags |= (rev ? WHERE_REVERSE : 0);
+      }else{
+        bSort = 1;
+      }
+    }
+
+    /* If currently calculating the cost of using an index (not the IPK
+    ** index), determine if all required column data may be obtained without 
+    ** seeking to entries in the main table (i.e. if the index is a covering
+    ** index for this query). If it is, set the WHERE_IDX_ONLY flag in
+    ** wsFlags. Otherwise, set the bLookup variable to true.  */
+    if( pIdx && wsFlags ){
+      Bitmask m = pSrc->colUsed;
+      int j;
+      for(j=0; j<pIdx->nColumn; j++){
+        int x = pIdx->aiColumn[j];
+        if( x<BMS-1 ){
+          m &= ~(((Bitmask)1)<<x);
         }
-        cc = cc->pNext;
       }
-      assert(cc);
+      if( m==0 ){
+        wsFlags |= WHERE_IDX_ONLY;
+      }else{
+        bLookup = 1;
+      }
+    }
+
+    /**** Begin adding up the cost of using this index (Needs improvements)
+    **
+    ** Estimate the number of rows of output.  For an IN operator,
+    ** do not let the estimate exceed half the rows in the table.
+    */
+    nRow = (double)(aiRowEst[nEq] * nInMul);
+    if( bInEst && nRow*2>aiRowEst[0] ){
+      nRow = aiRowEst[0]/2;
+      nInMul = (int)(nRow / aiRowEst[nEq]);
+    }
+
+    /* Assume constant cost to access a row and logarithmic cost to
+    ** do a binary search.  Hence, the initial cost is the number of output
+    ** rows plus log2(table-size) times the number of binary searches.
+    */
+    cost = nRow + nInMul*estLog(aiRowEst[0]);
+
+    /* Adjust the number of rows and the cost downward to reflect rows
+    ** that are excluded by range constraints.
+    */
+    nRow = (nRow * (double)nBound) / (double)100;
+    cost = (cost * (double)nBound) / (double)100;
+
+    /* Add in the estimated cost of sorting the result
+    */
+    if( bSort ){
+      cost += cost*estLog(cost);
     }
-    sqlite3DeleteTrigger(pTrigger);
-    db->flags |= SQLITE_InternChanges;
-  }
+
+    /* If all information can be taken directly from the index, we avoid
+    ** doing table lookups.  This reduces the cost by half.  (Not really -
+    ** this needs to be fixed.)
+    */
+    if( pIdx && bLookup==0 ){
+      cost /= (double)2;
+    }
+    /**** Cost of using this index has now been computed ****/
+
+    WHERETRACE((
+      "tbl=%s idx=%s nEq=%d nInMul=%d nBound=%d bSort=%d bLookup=%d"
+      " wsFlags=%d   (nRow=%.2f cost=%.2f)\n",
+      pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk"), 
+      nEq, nInMul, nBound, bSort, bLookup, wsFlags, nRow, cost
+    ));
+
+    /* If this index is the best we have seen so far, then record this
+    ** index and its cost in the pCost structure.
+    */
+    if( (!pIdx || wsFlags) && cost<pCost->rCost ){
+      pCost->rCost = cost;
+      pCost->nRow = nRow;
+      pCost->used = used;
+      pCost->plan.wsFlags = (wsFlags&wsFlagMask);
+      pCost->plan.nEq = nEq;
+      pCost->plan.u.pIdx = pIdx;
+    }
+
+    /* If there was an INDEXED BY clause, then only that one index is
+    ** considered. */
+    if( pSrc->pIndex ) break;
+
+    /* Reset masks for the next index in the loop */
+    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
+    eqTermMask = idxEqTermMask;
+  }
+
+  /* If there is no ORDER BY clause and the SQLITE_ReverseOrder flag
+  ** is set, then reverse the order that the index will be scanned
+  ** in. This is used for application testing, to help find cases
+  ** where application behaviour depends on the (undefined) order that
+  ** SQLite outputs rows in in the absence of an ORDER BY clause.  */
+  if( !pOrderBy && pParse->db->flags & SQLITE_ReverseOrder ){
+    pCost->plan.wsFlags |= WHERE_REVERSE;
+  }
+
+  assert( pOrderBy || (pCost->plan.wsFlags&WHERE_ORDERBY)==0 );
+  assert( pCost->plan.u.pIdx==0 || (pCost->plan.wsFlags&WHERE_ROWID_EQ)==0 );
+  assert( pSrc->pIndex==0 
+       || pCost->plan.u.pIdx==0 
+       || pCost->plan.u.pIdx==pSrc->pIndex 
+  );
+
+  WHERETRACE(("best index is: %s\n", 
+    (pCost->plan.u.pIdx ? pCost->plan.u.pIdx->zName : "ipk")
+  ));
+  
+  bestOrClauseIndex(pParse, pWC, pSrc, notReady, pOrderBy, pCost);
+  pCost->plan.wsFlags |= eqTermMask;
 }
 
 /*
-** pEList is the SET clause of an UPDATE statement.  Each entry
-** in pEList is of the format <id>=<expr>.  If any of the entries
-** in pEList have an <id> which matches an identifier in pIdList,
-** then return TRUE.  If pIdList==NULL, then it is considered a
-** wildcard that matches anything.  Likewise if pEList==NULL then
-** it matches anything so always return true.  Return false only
-** if there is no match.
+** Find the query plan for accessing table pSrc->pTab. Write the
+** best query plan and its cost into the WhereCost object supplied 
+** as the last parameter. This function may calculate the cost of
+** both real and virtual table scans.
 */
-static int checkColumnOverLap(IdList *pIdList, ExprList *pEList){
-  int e;
-  if( !pIdList || !pEList ) return 1;
-  for(e=0; e<pEList->nExpr; e++){
-    if( sqlite3IdListIndex(pIdList, pEList->a[e].zName)>=0 ) return 1;
+static void bestIndex(
+  Parse *pParse,              /* The parsing context */
+  WhereClause *pWC,           /* The WHERE clause */
+  struct SrcList_item *pSrc,  /* The FROM clause term to search */
+  Bitmask notReady,           /* Mask of cursors that are not available */
+  ExprList *pOrderBy,         /* The ORDER BY clause */
+  WhereCost *pCost            /* Lowest cost query plan */
+){
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  if( IsVirtual(pSrc->pTab) ){
+    sqlite3_index_info *p = 0;
+    bestVirtualIndex(pParse, pWC, pSrc, notReady, pOrderBy, pCost, &p);
+    if( p->needToFreeIdxStr ){
+      sqlite3_free(p->idxStr);
+    }
+    sqlite3DbFree(pParse->db, p);
+  }else
+#endif
+  {
+    bestBtreeIndex(pParse, pWC, pSrc, notReady, pOrderBy, pCost);
   }
-  return 0; 
 }
 
 /*
-** Return a bit vector to indicate what kind of triggers exist for operation
-** "op" on table pTab.  If pChanges is not NULL then it is a list of columns
-** that are being updated.  Triggers only match if the ON clause of the
-** trigger definition overlaps the set of columns being updated.
+** Disable a term in the WHERE clause.  Except, do not disable the term
+** if it controls a LEFT OUTER JOIN and it did not originate in the ON
+** or USING clause of that join.
+**
+** Consider the term t2.z='ok' in the following queries:
+**
+**   (1)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x WHERE t2.z='ok'
+**   (2)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x AND t2.z='ok'
+**   (3)  SELECT * FROM t1, t2 WHERE t1.a=t2.x AND t2.z='ok'
+**
+** The t2.z='ok' is disabled in the in (2) because it originates
+** in the ON clause.  The term is disabled in (3) because it is not part
+** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
 **
-** The returned bit vector is some combination of TRIGGER_BEFORE and
-** TRIGGER_AFTER.
+** Disabling a term causes that term to not be tested in the inner loop
+** of the join.  Disabling is an optimization.  When terms are satisfied
+** by indices, we disable them to prevent redundant tests in the inner
+** loop.  We would get the correct results if nothing were ever disabled,
+** but joins might run a little slower.  The trick is to disable as much
+** as we can without disabling too much.  If we disabled in (1), we'd get
+** the wrong answer.  See ticket #813.
 */
-SQLITE_PRIVATE int sqlite3TriggersExist(
-  Parse *pParse,          /* Used to check for recursive triggers */
-  Table *pTab,            /* The table the contains the triggers */
-  int op,                 /* one of TK_DELETE, TK_INSERT, TK_UPDATE */
-  ExprList *pChanges      /* Columns that change in an UPDATE statement */
-){
-  Trigger *pTrigger;
-  int mask = 0;
-
-  pTrigger = IsVirtual(pTab) ? 0 : pTab->pTrigger;
-  while( pTrigger ){
-    if( pTrigger->op==op && checkColumnOverLap(pTrigger->pColumns, pChanges) ){
-      mask |= pTrigger->tr_tm;
+static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
+  if( pTerm
+      && ALWAYS((pTerm->wtFlags & TERM_CODED)==0)
+      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
+  ){
+    pTerm->wtFlags |= TERM_CODED;
+    if( pTerm->iParent>=0 ){
+      WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
+      if( (--pOther->nChild)==0 ){
+        disableTerm(pLevel, pOther);
+      }
     }
-    pTrigger = pTrigger->pNext;
   }
-  return mask;
 }
 
 /*
-** Convert the pStep->target token into a SrcList and return a pointer
-** to that SrcList.
+** Code an OP_Affinity opcode to apply the column affinity string zAff
+** to the n registers starting at base. 
 **
-** This routine adds a specific database name, if needed, to the target when
-** forming the SrcList.  This prevents a trigger in one database from
-** referring to a target in another database.  An exception is when the
-** trigger is in TEMP in which case it can refer to any other database it
-** wants.
+** Buffer zAff was allocated using sqlite3DbMalloc(). It is the 
+** responsibility of this function to arrange for it to be eventually
+** freed using sqlite3DbFree().
 */
-static SrcList *targetSrcList(
-  Parse *pParse,       /* The parsing context */
-  TriggerStep *pStep   /* The trigger containing the target token */
-){
-  Token sDb;           /* Dummy database name token */
-  int iDb;             /* Index of the database to use */
-  SrcList *pSrc;       /* SrcList to be returned */
-
-  iDb = sqlite3SchemaToIndex(pParse->db, pStep->pTrig->pSchema);
-  if( iDb==0 || iDb>=2 ){
-    assert( iDb<pParse->db->nDb );
-    sDb.z = (u8*)pParse->db->aDb[iDb].zName;
-    sDb.n = strlen((char*)sDb.z);
-    pSrc = sqlite3SrcListAppend(pParse->db, 0, &sDb, &pStep->target);
-  } else {
-    pSrc = sqlite3SrcListAppend(pParse->db, 0, &pStep->target, 0);
-  }
-  return pSrc;
+static void codeApplyAffinity(Parse *pParse, int base, int n, char *zAff){
+  Vdbe *v = pParse->pVdbe;
+  assert( v!=0 );
+  sqlite3VdbeAddOp2(v, OP_Affinity, base, n);
+  sqlite3VdbeChangeP4(v, -1, zAff, P4_DYNAMIC);
+  sqlite3ExprCacheAffinityChange(pParse, base, n);
 }
 
+
 /*
-** Generate VDBE code for zero or more statements inside the body of a
-** trigger.  
+** Generate code for a single equality term of the WHERE clause.  An equality
+** term can be either X=expr or X IN (...).   pTerm is the term to be 
+** coded.
+**
+** The current value for the constraint is left in register iReg.
+**
+** For a constraint of the form X=expr, the expression is evaluated and its
+** result is left on the stack.  For constraints of the form X IN (...)
+** this routine sets up a loop that will iterate over all values of X.
 */
-static int codeTriggerProgram(
-  Parse *pParse,            /* The parser context */
-  TriggerStep *pStepList,   /* List of statements inside the trigger body */
-  int orconfin              /* Conflict algorithm. (OE_Abort, etc) */  
+static int codeEqualityTerm(
+  Parse *pParse,      /* The parsing context */
+  WhereTerm *pTerm,   /* The term of the WHERE clause to be coded */
+  WhereLevel *pLevel, /* When level of the FROM clause we are working on */
+  int iTarget         /* Attempt to leave results in this register */
 ){
-  TriggerStep * pTriggerStep = pStepList;
-  int orconf;
+  Expr *pX = pTerm->pExpr;
   Vdbe *v = pParse->pVdbe;
-  sqlite3 *db = pParse->db;
+  int iReg;                  /* Register holding results */
 
-  assert( pTriggerStep!=0 );
-  assert( v!=0 );
-  sqlite3VdbeAddOp2(v, OP_ContextPush, 0, 0);
-  VdbeComment((v, "begin trigger %s", pStepList->pTrig->name));
-  while( pTriggerStep ){
-    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
-    pParse->trigStack->orconf = orconf;
-    switch( pTriggerStep->op ){
-      case TK_SELECT: {
-        Select *ss = sqlite3SelectDup(db, pTriggerStep->pSelect);
-        if( ss ){
-          SelectDest dest;
-
-          sqlite3SelectDestInit(&dest, SRT_Discard, 0);
-          sqlite3SelectResolve(pParse, ss, 0);
-          sqlite3Select(pParse, ss, &dest, 0, 0, 0, 0);
-          sqlite3SelectDelete(ss);
-        }
-        break;
-      }
-      case TK_UPDATE: {
-        SrcList *pSrc;
-        pSrc = targetSrcList(pParse, pTriggerStep);
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
-        sqlite3Update(pParse, pSrc,
-                sqlite3ExprListDup(db, pTriggerStep->pExprList), 
-                sqlite3ExprDup(db, pTriggerStep->pWhere), orconf);
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
-        break;
-      }
-      case TK_INSERT: {
-        SrcList *pSrc;
-        pSrc = targetSrcList(pParse, pTriggerStep);
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
-        sqlite3Insert(pParse, pSrc,
-          sqlite3ExprListDup(db, pTriggerStep->pExprList), 
-          sqlite3SelectDup(db, pTriggerStep->pSelect), 
-          sqlite3IdListDup(db, pTriggerStep->pIdList), orconf);
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
-        break;
-      }
-      case TK_DELETE: {
-        SrcList *pSrc;
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
-        pSrc = targetSrcList(pParse, pTriggerStep);
-        sqlite3DeleteFrom(pParse, pSrc, 
-                          sqlite3ExprDup(db, pTriggerStep->pWhere));
-        sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
-        break;
+  assert( iTarget>0 );
+  if( pX->op==TK_EQ ){
+    iReg = sqlite3ExprCodeTarget(pParse, pX->pRight, iTarget);
+  }else if( pX->op==TK_ISNULL ){
+    iReg = iTarget;
+    sqlite3VdbeAddOp2(v, OP_Null, 0, iReg);
+#ifndef SQLITE_OMIT_SUBQUERY
+  }else{
+    int eType;
+    int iTab;
+    struct InLoop *pIn;
+
+    assert( pX->op==TK_IN );
+    iReg = iTarget;
+    eType = sqlite3FindInIndex(pParse, pX, 0);
+    iTab = pX->iTable;
+    sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
+    assert( pLevel->plan.wsFlags & WHERE_IN_ABLE );
+    if( pLevel->u.in.nIn==0 ){
+      pLevel->addrNxt = sqlite3VdbeMakeLabel(v);
+    }
+    pLevel->u.in.nIn++;
+    pLevel->u.in.aInLoop =
+       sqlite3DbReallocOrFree(pParse->db, pLevel->u.in.aInLoop,
+                              sizeof(pLevel->u.in.aInLoop[0])*pLevel->u.in.nIn);
+    pIn = pLevel->u.in.aInLoop;
+    if( pIn ){
+      pIn += pLevel->u.in.nIn - 1;
+      pIn->iCur = iTab;
+      if( eType==IN_INDEX_ROWID ){
+        pIn->addrInTop = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iReg);
+      }else{
+        pIn->addrInTop = sqlite3VdbeAddOp3(v, OP_Column, iTab, 0, iReg);
       }
-      default:
-        assert(0);
-    } 
-    pTriggerStep = pTriggerStep->pNext;
+      sqlite3VdbeAddOp1(v, OP_IsNull, iReg);
+    }else{
+      pLevel->u.in.nIn = 0;
+    }
+#endif
   }
-  sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
-  VdbeComment((v, "end trigger %s", pStepList->pTrig->name));
-
-  return 0;
+  disableTerm(pLevel, pTerm);
+  return iReg;
 }
 
 /*
-** This is called to code FOR EACH ROW triggers.
+** Generate code that will evaluate all == and IN constraints for an
+** index.  The values for all constraints are left on the stack.
 **
-** When the code that this function generates is executed, the following 
-** must be true:
+** For example, consider table t1(a,b,c,d,e,f) with index i1(a,b,c).
+** Suppose the WHERE clause is this:  a==5 AND b IN (1,2,3) AND c>5 AND c<10
+** The index has as many as three equality constraints, but in this
+** example, the third "c" value is an inequality.  So only two 
+** constraints are coded.  This routine will generate code to evaluate
+** a==5 and b IN (1,2,3).  The current values for a and b will be stored
+** in consecutive registers and the index of the first register is returned.
 **
-** 1. No cursors may be open in the main database.  (But newIdx and oldIdx
-**    can be indices of cursors in temporary tables.  See below.)
+** In the example above nEq==2.  But this subroutine works for any value
+** of nEq including 0.  If nEq==0, this routine is nearly a no-op.
+** The only thing it does is allocate the pLevel->iMem memory cell.
 **
-** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
-**    a temporary vdbe cursor (index newIdx) must be open and pointing at
-**    a row containing values to be substituted for new.* expressions in the
-**    trigger program(s).
+** This routine always allocates at least one memory cell and returns
+** the index of that memory cell. The code that
+** calls this routine will use that memory cell to store the termination
+** key value of the loop.  If one or more IN operators appear, then
+** this routine allocates an additional nEq memory cells for internal
+** use.
 **
-** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
-**    a temporary vdbe cursor (index oldIdx) must be open and pointing at
-**    a row containing values to be substituted for old.* expressions in the
-**    trigger program(s).
+** Before returning, *pzAff is set to point to a buffer containing a
+** copy of the column affinity string of the index allocated using
+** sqlite3DbMalloc(). Except, entries in the copy of the string associated
+** with equality constraints that use NONE affinity are set to
+** SQLITE_AFF_NONE. This is to deal with SQL such as the following:
 **
-** If they are not NULL, the piOldColMask and piNewColMask output variables
-** are set to values that describe the columns used by the trigger program
-** in the OLD.* and NEW.* tables respectively. If column N of the 
-** pseudo-table is read at least once, the corresponding bit of the output
-** mask is set. If a column with an index greater than 32 is read, the
-** output mask is set to the special value 0xffffffff.
+**   CREATE TABLE t1(a TEXT PRIMARY KEY, b);
+**   SELECT ... FROM t1 AS t2, t1 WHERE t1.a = t2.b;
 **
+** In the example above, the index on t1(a) has TEXT affinity. But since
+** the right hand side of the equality constraint (t2.b) has NONE affinity,
+** no conversion should be attempted before using a t2.b value as part of
+** a key to search the index. Hence the first byte in the returned affinity
+** string in this example would be set to SQLITE_AFF_NONE.
 */
-SQLITE_PRIVATE int sqlite3CodeRowTrigger(
-  Parse *pParse,       /* Parse context */
-  int op,              /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
-  ExprList *pChanges,  /* Changes list for any UPDATE OF triggers */
-  int tr_tm,           /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
-  Table *pTab,         /* The table to code triggers from */
-  int newIdx,          /* The indice of the "new" row to access */
-  int oldIdx,          /* The indice of the "old" row to access */
-  int orconf,          /* ON CONFLICT policy */
-  int ignoreJump,      /* Instruction to jump to for RAISE(IGNORE) */
-  u32 *piOldColMask,   /* OUT: Mask of columns used from the OLD.* table */
-  u32 *piNewColMask    /* OUT: Mask of columns used from the NEW.* table */
+static int codeAllEqualityTerms(
+  Parse *pParse,        /* Parsing context */
+  WhereLevel *pLevel,   /* Which nested loop of the FROM we are coding */
+  WhereClause *pWC,     /* The WHERE clause */
+  Bitmask notReady,     /* Which parts of FROM have not yet been coded */
+  int nExtraReg,        /* Number of extra registers to allocate */
+  char **pzAff          /* OUT: Set to point to affinity string */
 ){
-  Trigger *p;
-  sqlite3 *db = pParse->db;
-  TriggerStack trigStackEntry;
-
-  trigStackEntry.oldColMask = 0;
-  trigStackEntry.newColMask = 0;
+  int nEq = pLevel->plan.nEq;   /* The number of == or IN constraints to code */
+  Vdbe *v = pParse->pVdbe;      /* The vm under construction */
+  Index *pIdx;                  /* The index being used for this loop */
+  int iCur = pLevel->iTabCur;   /* The cursor of the table */
+  WhereTerm *pTerm;             /* A single constraint term */
+  int j;                        /* Loop counter */
+  int regBase;                  /* Base register */
+  int nReg;                     /* Number of registers to allocate */
+  char *zAff;                   /* Affinity string to return */
 
-  assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
-  assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
+  /* This module is only called on query plans that use an index. */
+  assert( pLevel->plan.wsFlags & WHERE_INDEXED );
+  pIdx = pLevel->plan.u.pIdx;
 
-  assert(newIdx != -1 || oldIdx != -1);
+  /* Figure out how many memory cells we will need then allocate them.
+  */
+  regBase = pParse->nMem + 1;
+  nReg = pLevel->plan.nEq + nExtraReg;
+  pParse->nMem += nReg;
 
-  for(p=pTab->pTrigger; p; p=p->pNext){
-    int fire_this = 0;
+  zAff = sqlite3DbStrDup(pParse->db, sqlite3IndexAffinityStr(v, pIdx));
+  if( !zAff ){
+    pParse->db->mallocFailed = 1;
+  }
 
-    /* Determine whether we should code this trigger */
-    if( 
-      p->op==op && 
-      p->tr_tm==tr_tm && 
-      (p->pSchema==p->pTabSchema || p->pSchema==db->aDb[1].pSchema) &&
-      (op!=TK_UPDATE||!p->pColumns||checkColumnOverLap(p->pColumns,pChanges))
-    ){
-      TriggerStack *pS;      /* Pointer to trigger-stack entry */
-      for(pS=pParse->trigStack; pS && p!=pS->pTrigger; pS=pS->pNext){}
-      if( !pS ){
-        fire_this = 1;
-      }
-#if 0    /* Give no warning for recursive triggers.  Just do not do them */
-      else{
-        sqlite3ErrorMsg(pParse, "recursive triggers not supported (%s)",
-            p->name);
-        return SQLITE_ERROR;
+  /* Evaluate the equality constraints
+  */
+  assert( pIdx->nColumn>=nEq );
+  for(j=0; j<nEq; j++){
+    int r1;
+    int k = pIdx->aiColumn[j];
+    pTerm = findTerm(pWC, iCur, k, notReady, pLevel->plan.wsFlags, pIdx);
+    if( NEVER(pTerm==0) ) break;
+    assert( (pTerm->wtFlags & TERM_CODED)==0 );
+    r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
+    if( r1!=regBase+j ){
+      if( nReg==1 ){
+        sqlite3ReleaseTempReg(pParse, regBase);
+        regBase = r1;
+      }else{
+        sqlite3VdbeAddOp2(v, OP_SCopy, r1, regBase+j);
       }
-#endif
     }
- 
-    if( fire_this ){
-      int endTrigger;
-      Expr * whenExpr;
-      AuthContext sContext;
-      NameContext sNC;
-
-#ifndef SQLITE_OMIT_TRACE
-      sqlite3VdbeAddOp4(pParse->pVdbe, OP_Trace, 0, 0, 0,
-                        sqlite3MPrintf(db, "-- TRIGGER %s", p->name),
-                        P4_DYNAMIC);
-#endif
-      memset(&sNC, 0, sizeof(sNC));
-      sNC.pParse = pParse;
-
-      /* Push an entry on to the trigger stack */
-      trigStackEntry.pTrigger = p;
-      trigStackEntry.newIdx = newIdx;
-      trigStackEntry.oldIdx = oldIdx;
-      trigStackEntry.pTab = pTab;
-      trigStackEntry.pNext = pParse->trigStack;
-      trigStackEntry.ignoreJump = ignoreJump;
-      pParse->trigStack = &trigStackEntry;
-      sqlite3AuthContextPush(pParse, &sContext, p->name);
-
-      /* code the WHEN clause */
-      endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
-      whenExpr = sqlite3ExprDup(db, p->pWhen);
-      if( db->mallocFailed || sqlite3ExprResolveNames(&sNC, whenExpr) ){
-        pParse->trigStack = trigStackEntry.pNext;
-        sqlite3ExprDelete(whenExpr);
-        return 1;
+    testcase( pTerm->eOperator & WO_ISNULL );
+    testcase( pTerm->eOperator & WO_IN );
+    if( (pTerm->eOperator & (WO_ISNULL|WO_IN))==0 ){
+      sqlite3VdbeAddOp2(v, OP_IsNull, regBase+j, pLevel->addrBrk);
+      if( zAff 
+       && sqlite3CompareAffinity(pTerm->pExpr->pRight, zAff[j])==SQLITE_AFF_NONE
+      ){
+        zAff[j] = SQLITE_AFF_NONE;
       }
-      sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, SQLITE_JUMPIFNULL);
-      sqlite3ExprDelete(whenExpr);
-
-      codeTriggerProgram(pParse, p->step_list, orconf); 
-
-      /* Pop the entry off the trigger stack */
-      pParse->trigStack = trigStackEntry.pNext;
-      sqlite3AuthContextPop(&sContext);
-
-      sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
     }
   }
-  if( piOldColMask ) *piOldColMask |= trigStackEntry.oldColMask;
-  if( piNewColMask ) *piNewColMask |= trigStackEntry.newColMask;
-  return 0;
+  *pzAff = zAff;
+  return regBase;
 }
-#endif /* !defined(SQLITE_OMIT_TRIGGER) */
 
-/************** End of trigger.c *********************************************/
-/************** Begin file update.c ******************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains C code routines that are called by the parser
-** to handle UPDATE statements.
-**
-** $Id: update.c,v 1.178 2008/04/28 18:46:43 drh Exp $
+** Generate code for the start of the iLevel-th loop in the WHERE clause
+** implementation described by pWInfo.
 */
+static Bitmask codeOneLoopStart(
+  WhereInfo *pWInfo,   /* Complete information about the WHERE clause */
+  int iLevel,          /* Which level of pWInfo->a[] should be coded */
+  u16 wctrlFlags,      /* One of the WHERE_* flags defined in sqliteInt.h */
+  Bitmask notReady     /* Which tables are currently available */
+){
+  int j, k;            /* Loop counters */
+  int iCur;            /* The VDBE cursor for the table */
+  int addrNxt;         /* Where to jump to continue with the next IN case */
+  int omitTable;       /* True if we use the index only */
+  int bRev;            /* True if we need to scan in reverse order */
+  WhereLevel *pLevel;  /* The where level to be coded */
+  WhereClause *pWC;    /* Decomposition of the entire WHERE clause */
+  WhereTerm *pTerm;               /* A WHERE clause term */
+  Parse *pParse;                  /* Parsing context */
+  Vdbe *v;                        /* The prepared stmt under constructions */
+  struct SrcList_item *pTabItem;  /* FROM clause term being coded */
+  int addrBrk;                    /* Jump here to break out of the loop */
+  int addrCont;                   /* Jump here to continue with next cycle */
+  int iRowidReg = 0;        /* Rowid is stored in this register, if not zero */
+  int iReleaseReg = 0;      /* Temp register to free before returning */
+
+  pParse = pWInfo->pParse;
+  v = pParse->pVdbe;
+  pWC = pWInfo->pWC;
+  pLevel = &pWInfo->a[iLevel];
+  pTabItem = &pWInfo->pTabList->a[pLevel->iFrom];
+  iCur = pTabItem->iCursor;
+  bRev = (pLevel->plan.wsFlags & WHERE_REVERSE)!=0;
+  omitTable = (pLevel->plan.wsFlags & WHERE_IDX_ONLY)!=0 
+           && (wctrlFlags & WHERE_FORCE_TABLE)==0;
+
+  /* Create labels for the "break" and "continue" instructions
+  ** for the current loop.  Jump to addrBrk to break out of a loop.
+  ** Jump to cont to go immediately to the next iteration of the
+  ** loop.
+  **
+  ** When there is an IN operator, we also have a "addrNxt" label that
+  ** means to continue with the next IN value combination.  When
+  ** there are no IN operators in the constraints, the "addrNxt" label
+  ** is the same as "addrBrk".
+  */
+  addrBrk = pLevel->addrBrk = pLevel->addrNxt = sqlite3VdbeMakeLabel(v);
+  addrCont = pLevel->addrCont = sqlite3VdbeMakeLabel(v);
+
+  /* If this is the right table of a LEFT OUTER JOIN, allocate and
+  ** initialize a memory cell that records if this table matches any
+  ** row of the left table of the join.
+  */
+  if( pLevel->iFrom>0 && (pTabItem[0].jointype & JT_LEFT)!=0 ){
+    pLevel->iLeftJoin = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, pLevel->iLeftJoin);
+    VdbeComment((v, "init LEFT JOIN no-match flag"));
+  }
 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Forward declaration */
-static void updateVirtualTable(
-  Parse *pParse,       /* The parsing context */
-  SrcList *pSrc,       /* The virtual table to be modified */
-  Table *pTab,         /* The virtual table */
-  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
-  Expr *pRowidExpr,    /* Expression used to recompute the rowid */
-  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
-  Expr *pWhere         /* WHERE clause of the UPDATE statement */
-);
+  if(  (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
+    /* Case 0:  The table is a virtual-table.  Use the VFilter and VNext
+    **          to access the data.
+    */
+    int iReg;   /* P3 Value for OP_VFilter */
+    sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
+    int nConstraint = pVtabIdx->nConstraint;
+    struct sqlite3_index_constraint_usage *aUsage =
+                                                pVtabIdx->aConstraintUsage;
+    const struct sqlite3_index_constraint *aConstraint =
+                                                pVtabIdx->aConstraint;
+
+    iReg = sqlite3GetTempRange(pParse, nConstraint+2);
+    for(j=1; j<=nConstraint; j++){
+      for(k=0; k<nConstraint; k++){
+        if( aUsage[k].argvIndex==j ){
+          int iTerm = aConstraint[k].iTermOffset;
+          sqlite3ExprCode(pParse, pWC->a[iTerm].pExpr->pRight, iReg+j+1);
+          break;
+        }
+      }
+      if( k==nConstraint ) break;
+    }
+    sqlite3VdbeAddOp2(v, OP_Integer, pVtabIdx->idxNum, iReg);
+    sqlite3VdbeAddOp2(v, OP_Integer, j-1, iReg+1);
+    sqlite3VdbeAddOp4(v, OP_VFilter, iCur, addrBrk, iReg, pVtabIdx->idxStr,
+                      pVtabIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
+    pVtabIdx->needToFreeIdxStr = 0;
+    for(j=0; j<nConstraint; j++){
+      if( aUsage[j].omit ){
+        int iTerm = aConstraint[j].iTermOffset;
+        disableTerm(pLevel, &pWC->a[iTerm]);
+      }
+    }
+    pLevel->op = OP_VNext;
+    pLevel->p1 = iCur;
+    pLevel->p2 = sqlite3VdbeCurrentAddr(v);
+    sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
+  }else
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/*
-** The most recently coded instruction was an OP_Column to retrieve the
-** i-th column of table pTab. This routine sets the P4 parameter of the 
-** OP_Column to the default value, if any.
-**
-** The default value of a column is specified by a DEFAULT clause in the 
-** column definition. This was either supplied by the user when the table
-** was created, or added later to the table definition by an ALTER TABLE
-** command. If the latter, then the row-records in the table btree on disk
-** may not contain a value for the column and the default value, taken
-** from the P4 parameter of the OP_Column instruction, is returned instead.
-** If the former, then all row-records are guaranteed to include a value
-** for the column and the P4 value is not required.
-**
-** Column definitions created by an ALTER TABLE command may only have 
-** literal default values specified: a number, null or a string. (If a more
-** complicated default expression value was provided, it is evaluated 
-** when the ALTER TABLE is executed and one of the literal values written
-** into the sqlite_master table.)
-**
-** Therefore, the P4 parameter is only required if the default value for
-** the column is a literal number, string or null. The sqlite3ValueFromExpr()
-** function is capable of transforming these types of expressions into
-** sqlite3_value objects.
-*/
-SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i){
-  if( pTab && !pTab->pSelect ){
-    sqlite3_value *pValue;
-    u8 enc = ENC(sqlite3VdbeDb(v));
-    Column *pCol = &pTab->aCol[i];
-    VdbeComment((v, "%s.%s", pTab->zName, pCol->zName));
-    assert( i<pTab->nCol );
-    sqlite3ValueFromExpr(sqlite3VdbeDb(v), pCol->pDflt, enc, 
-                         pCol->affinity, &pValue);
-    if( pValue ){
-      sqlite3VdbeChangeP4(v, -1, (const char *)pValue, P4_MEM);
+  if( pLevel->plan.wsFlags & WHERE_ROWID_EQ ){
+    /* Case 1:  We can directly reference a single row using an
+    **          equality comparison against the ROWID field.  Or
+    **          we reference multiple rows using a "rowid IN (...)"
+    **          construct.
+    */
+    iReleaseReg = sqlite3GetTempReg(pParse);
+    pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
+    assert( pTerm!=0 );
+    assert( pTerm->pExpr!=0 );
+    assert( pTerm->leftCursor==iCur );
+    assert( omitTable==0 );
+    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, iReleaseReg);
+    addrNxt = pLevel->addrNxt;
+    sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
+    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addrNxt, iRowidReg);
+    sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg);
+    VdbeComment((v, "pk"));
+    pLevel->op = OP_Noop;
+  }else if( pLevel->plan.wsFlags & WHERE_ROWID_RANGE ){
+    /* Case 2:  We have an inequality comparison against the ROWID field.
+    */
+    int testOp = OP_Noop;
+    int start;
+    int memEndValue = 0;
+    WhereTerm *pStart, *pEnd;
+
+    assert( omitTable==0 );
+    pStart = findTerm(pWC, iCur, -1, notReady, WO_GT|WO_GE, 0);
+    pEnd = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0);
+    if( bRev ){
+      pTerm = pStart;
+      pStart = pEnd;
+      pEnd = pTerm;
+    }
+    if( pStart ){
+      Expr *pX;             /* The expression that defines the start bound */
+      int r1, rTemp;        /* Registers for holding the start boundary */
+
+      /* The following constant maps TK_xx codes into corresponding 
+      ** seek opcodes.  It depends on a particular ordering of TK_xx
+      */
+      const u8 aMoveOp[] = {
+           /* TK_GT */  OP_SeekGt,
+           /* TK_LE */  OP_SeekLe,
+           /* TK_LT */  OP_SeekLt,
+           /* TK_GE */  OP_SeekGe
+      };
+      assert( TK_LE==TK_GT+1 );      /* Make sure the ordering.. */
+      assert( TK_LT==TK_GT+2 );      /*  ... of the TK_xx values... */
+      assert( TK_GE==TK_GT+3 );      /*  ... is correcct. */
+
+      pX = pStart->pExpr;
+      assert( pX!=0 );
+      assert( pStart->leftCursor==iCur );
+      r1 = sqlite3ExprCodeTemp(pParse, pX->pRight, &rTemp);
+      sqlite3VdbeAddOp3(v, aMoveOp[pX->op-TK_GT], iCur, addrBrk, r1);
+      VdbeComment((v, "pk"));
+      sqlite3ExprCacheAffinityChange(pParse, r1, 1);
+      sqlite3ReleaseTempReg(pParse, rTemp);
+      disableTerm(pLevel, pStart);
+    }else{
+      sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iCur, addrBrk);
+    }
+    if( pEnd ){
+      Expr *pX;
+      pX = pEnd->pExpr;
+      assert( pX!=0 );
+      assert( pEnd->leftCursor==iCur );
+      memEndValue = ++pParse->nMem;
+      sqlite3ExprCode(pParse, pX->pRight, memEndValue);
+      if( pX->op==TK_LT || pX->op==TK_GT ){
+        testOp = bRev ? OP_Le : OP_Ge;
+      }else{
+        testOp = bRev ? OP_Lt : OP_Gt;
+      }
+      disableTerm(pLevel, pEnd);
+    }
+    start = sqlite3VdbeCurrentAddr(v);
+    pLevel->op = bRev ? OP_Prev : OP_Next;
+    pLevel->p1 = iCur;
+    pLevel->p2 = start;
+    pLevel->p5 = (pStart==0 && pEnd==0) ?1:0;
+    if( testOp!=OP_Noop ){
+      iRowidReg = iReleaseReg = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp2(v, OP_Rowid, iCur, iRowidReg);
+      sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg);
+      sqlite3VdbeAddOp3(v, testOp, memEndValue, addrBrk, iRowidReg);
+      sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC | SQLITE_JUMPIFNULL);
+    }
+  }else if( pLevel->plan.wsFlags & (WHERE_COLUMN_RANGE|WHERE_COLUMN_EQ) ){
+    /* Case 3: A scan using an index.
+    **
+    **         The WHERE clause may contain zero or more equality 
+    **         terms ("==" or "IN" operators) that refer to the N
+    **         left-most columns of the index. It may also contain
+    **         inequality constraints (>, <, >= or <=) on the indexed
+    **         column that immediately follows the N equalities. Only 
+    **         the right-most column can be an inequality - the rest must
+    **         use the "==" and "IN" operators. For example, if the 
+    **         index is on (x,y,z), then the following clauses are all 
+    **         optimized:
+    **
+    **            x=5
+    **            x=5 AND y=10
+    **            x=5 AND y<10
+    **            x=5 AND y>5 AND y<10
+    **            x=5 AND y=5 AND z<=10
+    **
+    **         The z<10 term of the following cannot be used, only
+    **         the x=5 term:
+    **
+    **            x=5 AND z<10
+    **
+    **         N may be zero if there are inequality constraints.
+    **         If there are no inequality constraints, then N is at
+    **         least one.
+    **
+    **         This case is also used when there are no WHERE clause
+    **         constraints but an index is selected anyway, in order
+    **         to force the output order to conform to an ORDER BY.
+    */  
+    int aStartOp[] = {
+      0,
+      0,
+      OP_Rewind,           /* 2: (!start_constraints && startEq &&  !bRev) */
+      OP_Last,             /* 3: (!start_constraints && startEq &&   bRev) */
+      OP_SeekGt,           /* 4: (start_constraints  && !startEq && !bRev) */
+      OP_SeekLt,           /* 5: (start_constraints  && !startEq &&  bRev) */
+      OP_SeekGe,           /* 6: (start_constraints  &&  startEq && !bRev) */
+      OP_SeekLe            /* 7: (start_constraints  &&  startEq &&  bRev) */
+    };
+    int aEndOp[] = {
+      OP_Noop,             /* 0: (!end_constraints) */
+      OP_IdxGE,            /* 1: (end_constraints && !bRev) */
+      OP_IdxLT             /* 2: (end_constraints && bRev) */
+    };
+    int nEq = pLevel->plan.nEq;
+    int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
+    int regBase;                 /* Base register holding constraint values */
+    int r1;                      /* Temp register */
+    WhereTerm *pRangeStart = 0;  /* Inequality constraint at range start */
+    WhereTerm *pRangeEnd = 0;    /* Inequality constraint at range end */
+    int startEq;                 /* True if range start uses ==, >= or <= */
+    int endEq;                   /* True if range end uses ==, >= or <= */
+    int start_constraints;       /* Start of range is constrained */
+    int nConstraint;             /* Number of constraint terms */
+    Index *pIdx;         /* The index we will be using */
+    int iIdxCur;         /* The VDBE cursor for the index */
+    int nExtraReg = 0;   /* Number of extra registers needed */
+    int op;              /* Instruction opcode */
+    char *zAff;
+
+    pIdx = pLevel->plan.u.pIdx;
+    iIdxCur = pLevel->iIdxCur;
+    k = pIdx->aiColumn[nEq];     /* Column for inequality constraints */
+
+    /* If this loop satisfies a sort order (pOrderBy) request that 
+    ** was passed to this function to implement a "SELECT min(x) ..." 
+    ** query, then the caller will only allow the loop to run for
+    ** a single iteration. This means that the first row returned
+    ** should not have a NULL value stored in 'x'. If column 'x' is
+    ** the first one after the nEq equality constraints in the index,
+    ** this requires some special handling.
+    */
+    if( (wctrlFlags&WHERE_ORDERBY_MIN)!=0
+     && (pLevel->plan.wsFlags&WHERE_ORDERBY)
+     && (pIdx->nColumn>nEq)
+    ){
+      /* assert( pOrderBy->nExpr==1 ); */
+      /* assert( pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq] ); */
+      isMinQuery = 1;
+      nExtraReg = 1;
     }
-  }
-}
-
-/*
-** Process an UPDATE statement.
-**
-**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
-**          \_______/ \________/     \______/       \________________/
-*            onError   pTabList      pChanges             pWhere
-*/
-SQLITE_PRIVATE void sqlite3Update(
-  Parse *pParse,         /* The parser context */
-  SrcList *pTabList,     /* The table in which we should change things */
-  ExprList *pChanges,    /* Things to be changed */
-  Expr *pWhere,          /* The WHERE clause.  May be null */
-  int onError            /* How to handle constraint errors */
-){
-  int i, j;              /* Loop counters */
-  Table *pTab;           /* The table to be updated */
-  int addr = 0;          /* VDBE instruction address of the start of the loop */
-  WhereInfo *pWInfo;     /* Information about the WHERE clause */
-  Vdbe *v;               /* The virtual database engine */
-  Index *pIdx;           /* For looping over indices */
-  int nIdx;              /* Number of indices that need updating */
-  int iCur;              /* VDBE Cursor number of pTab */
-  sqlite3 *db;           /* The database structure */
-  int *aRegIdx = 0;      /* One register assigned to each index to be updated */
-  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
-                         ** an expression for the i-th column of the table.
-                         ** aXRef[i]==-1 if the i-th column is not changed. */
-  int chngRowid;         /* True if the record number is being changed */
-  Expr *pRowidExpr = 0;  /* Expression defining the new record number */
-  int openAll = 0;       /* True if all indices need to be opened */
-  AuthContext sContext;  /* The authorization context */
-  NameContext sNC;       /* The name-context to resolve expressions in */
-  int iDb;               /* Database containing the table being updated */
-  int j1;                /* Addresses of jump instructions */
-  int okOnePass;         /* True for one-pass algorithm without the FIFO */
-
-#ifndef SQLITE_OMIT_TRIGGER
-  int isView;                  /* Trying to update a view */
-  int triggers_exist = 0;      /* True if any row triggers exist */
-#endif
-  int iBeginAfterTrigger;      /* Address of after trigger program */
-  int iEndAfterTrigger;        /* Exit of after trigger program */
-  int iBeginBeforeTrigger;     /* Address of before trigger program */
-  int iEndBeforeTrigger;       /* Exit of before trigger program */
-  u32 old_col_mask = 0;        /* Mask of OLD.* columns in use */
-  u32 new_col_mask = 0;        /* Mask of NEW.* columns in use */
 
-  int newIdx      = -1;  /* index of trigger "new" temp table       */
-  int oldIdx      = -1;  /* index of trigger "old" temp table       */
+    /* Find any inequality constraint terms for the start and end 
+    ** of the range. 
+    */
+    if( pLevel->plan.wsFlags & WHERE_TOP_LIMIT ){
+      pRangeEnd = findTerm(pWC, iCur, k, notReady, (WO_LT|WO_LE), pIdx);
+      nExtraReg = 1;
+    }
+    if( pLevel->plan.wsFlags & WHERE_BTM_LIMIT ){
+      pRangeStart = findTerm(pWC, iCur, k, notReady, (WO_GT|WO_GE), pIdx);
+      nExtraReg = 1;
+    }
 
-  /* Register Allocations */
-  int regRowCount = 0;   /* A count of rows changed */
-  int regOldRowid;       /* The old rowid */
-  int regNewRowid;       /* The new rowid */
-  int regData;           /* New data for the row */
+    /* Generate code to evaluate all constraint terms using == or IN
+    ** and store the values of those terms in an array of registers
+    ** starting at regBase.
+    */
+    regBase = codeAllEqualityTerms(
+        pParse, pLevel, pWC, notReady, nExtraReg, &zAff
+    );
+    addrNxt = pLevel->addrNxt;
 
-  sContext.pParse = 0;
-  db = pParse->db;
-  if( pParse->nErr || db->mallocFailed ){
-    goto update_cleanup;
-  }
-  assert( pTabList->nSrc==1 );
+    /* If we are doing a reverse order scan on an ascending index, or
+    ** a forward order scan on a descending index, interchange the 
+    ** start and end terms (pRangeStart and pRangeEnd).
+    */
+    if( bRev==(pIdx->aSortOrder[nEq]==SQLITE_SO_ASC) ){
+      SWAP(WhereTerm *, pRangeEnd, pRangeStart);
+    }
+
+    testcase( pRangeStart && pRangeStart->eOperator & WO_LE );
+    testcase( pRangeStart && pRangeStart->eOperator & WO_GE );
+    testcase( pRangeEnd && pRangeEnd->eOperator & WO_LE );
+    testcase( pRangeEnd && pRangeEnd->eOperator & WO_GE );
+    startEq = !pRangeStart || pRangeStart->eOperator & (WO_LE|WO_GE);
+    endEq =   !pRangeEnd || pRangeEnd->eOperator & (WO_LE|WO_GE);
+    start_constraints = pRangeStart || nEq>0;
+
+    /* Seek the index cursor to the start of the range. */
+    nConstraint = nEq;
+    if( pRangeStart ){
+      Expr *pRight = pRangeStart->pExpr->pRight;
+      sqlite3ExprCode(pParse, pRight, regBase+nEq);
+      sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
+      if( zAff 
+       && sqlite3CompareAffinity(pRight, zAff[nConstraint])==SQLITE_AFF_NONE
+      ){
+        /* Since the comparison is to be performed with no conversions applied
+        ** to the operands, set the affinity to apply to pRight to 
+        ** SQLITE_AFF_NONE.  */
+        zAff[nConstraint] = SQLITE_AFF_NONE;
+      }
+      nConstraint++;
+    }else if( isMinQuery ){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
+      nConstraint++;
+      startEq = 0;
+      start_constraints = 1;
+    }
+    codeApplyAffinity(pParse, regBase, nConstraint, zAff);
+    op = aStartOp[(start_constraints<<2) + (startEq<<1) + bRev];
+    assert( op!=0 );
+    testcase( op==OP_Rewind );
+    testcase( op==OP_Last );
+    testcase( op==OP_SeekGt );
+    testcase( op==OP_SeekGe );
+    testcase( op==OP_SeekLe );
+    testcase( op==OP_SeekLt );
+    sqlite3VdbeAddOp4(v, op, iIdxCur, addrNxt, regBase, 
+                      SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
+
+    /* Load the value for the inequality constraint at the end of the
+    ** range (if any).
+    */
+    nConstraint = nEq;
+    if( pRangeEnd ){
+      Expr *pRight = pRangeEnd->pExpr->pRight;
+      sqlite3ExprCacheRemove(pParse, regBase+nEq);
+      sqlite3ExprCode(pParse, pRight, regBase+nEq);
+      sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
+      zAff = sqlite3DbStrDup(pParse->db, zAff);
+      if( zAff 
+       && sqlite3CompareAffinity(pRight, zAff[nConstraint])==SQLITE_AFF_NONE
+      ){
+        /* Since the comparison is to be performed with no conversions applied
+        ** to the operands, set the affinity to apply to pRight to 
+        ** SQLITE_AFF_NONE.  */
+        zAff[nConstraint] = SQLITE_AFF_NONE;
+      }
+      codeApplyAffinity(pParse, regBase, nEq+1, zAff);
+      nConstraint++;
+    }
 
-  /* Locate the table which we want to update. 
-  */
-  pTab = sqlite3SrcListLookup(pParse, pTabList);
-  if( pTab==0 ) goto update_cleanup;
-  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+    /* Top of the loop body */
+    pLevel->p2 = sqlite3VdbeCurrentAddr(v);
 
-  /* Figure out if we have any triggers and if the table being
-  ** updated is a view
-  */
-#ifndef SQLITE_OMIT_TRIGGER
-  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
-  isView = pTab->pSelect!=0;
-#else
-# define triggers_exist 0
-# define isView 0
-#endif
-#ifdef SQLITE_OMIT_VIEW
-# undef isView
-# define isView 0
-#endif
+    /* Check if the index cursor is past the end of the range. */
+    op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
+    testcase( op==OP_Noop );
+    testcase( op==OP_IdxGE );
+    testcase( op==OP_IdxLT );
+    if( op!=OP_Noop ){
+      sqlite3VdbeAddOp4(v, op, iIdxCur, addrNxt, regBase,
+                        SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
+      sqlite3VdbeChangeP5(v, endEq!=bRev ?1:0);
+    }
 
-  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
-    goto update_cleanup;
-  }
-  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-    goto update_cleanup;
-  }
-  aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
-  if( aXRef==0 ) goto update_cleanup;
-  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
+    /* If there are inequality constraints, check that the value
+    ** of the table column that the inequality contrains is not NULL.
+    ** If it is, jump to the next iteration of the loop.
+    */
+    r1 = sqlite3GetTempReg(pParse);
+    testcase( pLevel->plan.wsFlags & WHERE_BTM_LIMIT );
+    testcase( pLevel->plan.wsFlags & WHERE_TOP_LIMIT );
+    if( pLevel->plan.wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT) ){
+      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
+      sqlite3VdbeAddOp2(v, OP_IsNull, r1, addrCont);
+    }
+    sqlite3ReleaseTempReg(pParse, r1);
 
-  /* If there are FOR EACH ROW triggers, allocate cursors for the
-  ** special OLD and NEW tables
-  */
-  if( triggers_exist ){
-    newIdx = pParse->nTab++;
-    oldIdx = pParse->nTab++;
-  }
+    /* Seek the table cursor, if required */
+    disableTerm(pLevel, pRangeStart);
+    disableTerm(pLevel, pRangeEnd);
+    if( !omitTable ){
+      iRowidReg = iReleaseReg = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, iRowidReg);
+      sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg);
+      sqlite3VdbeAddOp2(v, OP_Seek, iCur, iRowidReg);  /* Deferred seek */
+    }
 
-  /* Allocate a cursors for the main database table and for all indices.
-  ** The index cursors might not be used, but if they are used they
-  ** need to occur right after the database cursor.  So go ahead and
-  ** allocate enough space, just in case.
-  */
-  pTabList->a[0].iCursor = iCur = pParse->nTab++;
-  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-    pParse->nTab++;
-  }
+    /* Record the instruction used to terminate the loop. Disable 
+    ** WHERE clause terms made redundant by the index range scan.
+    */
+    pLevel->op = bRev ? OP_Prev : OP_Next;
+    pLevel->p1 = iIdxCur;
+  }else
 
-  /* Initialize the name-context */
-  memset(&sNC, 0, sizeof(sNC));
-  sNC.pParse = pParse;
-  sNC.pSrcList = pTabList;
+#ifndef SQLITE_OMIT_OR_OPTIMIZATION
+  if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
+    /* Case 4:  Two or more separately indexed terms connected by OR
+    **
+    ** Example:
+    **
+    **   CREATE TABLE t1(a,b,c,d);
+    **   CREATE INDEX i1 ON t1(a);
+    **   CREATE INDEX i2 ON t1(b);
+    **   CREATE INDEX i3 ON t1(c);
+    **
+    **   SELECT * FROM t1 WHERE a=5 OR b=7 OR (c=11 AND d=13)
+    **
+    ** In the example, there are three indexed terms connected by OR.
+    ** The top of the loop looks like this:
+    **
+    **          Null       1                # Zero the rowset in reg 1
+    **
+    ** Then, for each indexed term, the following. The arguments to
+    ** RowSetTest are such that the rowid of the current row is inserted
+    ** into the RowSet. If it is already present, control skips the
+    ** Gosub opcode and jumps straight to the code generated by WhereEnd().
+    **
+    **        sqlite3WhereBegin(<term>)
+    **          RowSetTest                  # Insert rowid into rowset
+    **          Gosub      2 A
+    **        sqlite3WhereEnd()
+    **
+    ** Following the above, code to terminate the loop. Label A, the target
+    ** of the Gosub above, jumps to the instruction right after the Goto.
+    **
+    **          Null       1                # Zero the rowset in reg 1
+    **          Goto       B                # The loop is finished.
+    **
+    **       A: <loop body>                 # Return data, whatever.
+    **
+    **          Return     2                # Jump back to the Gosub
+    **
+    **       B: <after the loop>
+    **
+    */
+    WhereClause *pOrWc;    /* The OR-clause broken out into subterms */
+    WhereTerm *pFinal;     /* Final subterm within the OR-clause. */
+    SrcList oneTab;        /* Shortened table list */
+
+    int regReturn = ++pParse->nMem;           /* Register used with OP_Gosub */
+    int regRowset = 0;                        /* Register for RowSet object */
+    int regRowid = 0;                         /* Register holding rowid */
+    int iLoopBody = sqlite3VdbeMakeLabel(v);  /* Start of loop body */
+    int iRetInit;                             /* Address of regReturn init */
+    int ii;
+   
+    pTerm = pLevel->plan.u.pTerm;
+    assert( pTerm!=0 );
+    assert( pTerm->eOperator==WO_OR );
+    assert( (pTerm->wtFlags & TERM_ORINFO)!=0 );
+    pOrWc = &pTerm->u.pOrInfo->wc;
+    pFinal = &pOrWc->a[pOrWc->nTerm-1];
+
+    /* Set up a SrcList containing just the table being scanned by this loop. */
+    oneTab.nSrc = 1;
+    oneTab.nAlloc = 1;
+    oneTab.a[0] = *pTabItem;
+
+    /* Initialize the rowset register to contain NULL. An SQL NULL is 
+    ** equivalent to an empty rowset.
+    **
+    ** Also initialize regReturn to contain the address of the instruction 
+    ** immediately following the OP_Return at the bottom of the loop. This
+    ** is required in a few obscure LEFT JOIN cases where control jumps
+    ** over the top of the loop into the body of it. In this case the 
+    ** correct response for the end-of-loop code (the OP_Return) is to 
+    ** fall through to the next instruction, just as an OP_Next does if
+    ** called on an uninitialized cursor.
+    */
+    if( (wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
+      regRowset = ++pParse->nMem;
+      regRowid = ++pParse->nMem;
+      sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset);
+    }
+    iRetInit = sqlite3VdbeAddOp2(v, OP_Integer, 0, regReturn);
+
+    for(ii=0; ii<pOrWc->nTerm; ii++){
+      WhereTerm *pOrTerm = &pOrWc->a[ii];
+      if( pOrTerm->leftCursor==iCur || pOrTerm->eOperator==WO_AND ){
+        WhereInfo *pSubWInfo;          /* Info for single OR-term scan */
+        /* Loop through table entries that match term pOrTerm. */
+        pSubWInfo = sqlite3WhereBegin(pParse, &oneTab, pOrTerm->pExpr, 0,
+                        WHERE_OMIT_OPEN | WHERE_OMIT_CLOSE | WHERE_FORCE_TABLE);
+        if( pSubWInfo ){
+          if( (wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
+            int iSet = ((ii==pOrWc->nTerm-1)?-1:ii);
+            int r;
+            r = sqlite3ExprCodeGetColumn(pParse, pTabItem->pTab, -1, iCur, 
+                                         regRowid, 0);
+            sqlite3VdbeAddOp4(v, OP_RowSetTest, regRowset,
+                              sqlite3VdbeCurrentAddr(v)+2,
+                              r, SQLITE_INT_TO_PTR(iSet), P4_INT32);
+          }
+          sqlite3VdbeAddOp2(v, OP_Gosub, regReturn, iLoopBody);
 
-  /* Resolve the column names in all the expressions of the
-  ** of the UPDATE statement.  Also find the column index
-  ** for each column to be updated in the pChanges array.  For each
-  ** column to be updated, make sure we have authorization to change
-  ** that column.
-  */
-  chngRowid = 0;
-  for(i=0; i<pChanges->nExpr; i++){
-    if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
-      goto update_cleanup;
-    }
-    for(j=0; j<pTab->nCol; j++){
-      if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
-        if( j==pTab->iPKey ){
-          chngRowid = 1;
-          pRowidExpr = pChanges->a[i].pExpr;
+          /* Finish the loop through table entries that match term pOrTerm. */
+          sqlite3WhereEnd(pSubWInfo);
         }
-        aXRef[j] = i;
-        break;
-      }
-    }
-    if( j>=pTab->nCol ){
-      if( sqlite3IsRowid(pChanges->a[i].zName) ){
-        chngRowid = 1;
-        pRowidExpr = pChanges->a[i].pExpr;
-      }else{
-        sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
-        goto update_cleanup;
       }
     }
-#ifndef SQLITE_OMIT_AUTHORIZATION
-    {
-      int rc;
-      rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
-                           pTab->aCol[j].zName, db->aDb[iDb].zName);
-      if( rc==SQLITE_DENY ){
-        goto update_cleanup;
-      }else if( rc==SQLITE_IGNORE ){
-        aXRef[j] = -1;
-      }
+    sqlite3VdbeChangeP1(v, iRetInit, sqlite3VdbeCurrentAddr(v));
+    /* sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset); */
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrBrk);
+    sqlite3VdbeResolveLabel(v, iLoopBody);
+
+    pLevel->op = OP_Return;
+    pLevel->p1 = regReturn;
+    disableTerm(pLevel, pTerm);
+  }else
+#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
+
+  {
+    /* Case 5:  There is no usable index.  We must do a complete
+    **          scan of the entire table.
+    */
+    static const u8 aStep[] = { OP_Next, OP_Prev };
+    static const u8 aStart[] = { OP_Rewind, OP_Last };
+    assert( bRev==0 || bRev==1 );
+    assert( omitTable==0 );
+    pLevel->op = aStep[bRev];
+    pLevel->p1 = iCur;
+    pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, aStart[bRev], iCur, addrBrk);
+    pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
+  }
+  notReady &= ~getMask(pWC->pMaskSet, iCur);
+
+  /* Insert code to test every subexpression that can be completely
+  ** computed using the current set of tables.
+  */
+  k = 0;
+  for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
+    Expr *pE;
+    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    testcase( pTerm->wtFlags & TERM_CODED );
+    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
+    if( (pTerm->prereqAll & notReady)!=0 ) continue;
+    pE = pTerm->pExpr;
+    assert( pE!=0 );
+    if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
+      continue;
     }
-#endif
+    sqlite3ExprIfFalse(pParse, pE, addrCont, SQLITE_JUMPIFNULL);
+    k = 1;
+    pTerm->wtFlags |= TERM_CODED;
   }
 
-  /* Allocate memory for the array aRegIdx[].  There is one entry in the
-  ** array for each index associated with table being updated.  Fill in
-  ** the value with a register number for indices that are to be used
-  ** and with zero for unused indices.
+  /* For a LEFT OUTER JOIN, generate code that will record the fact that
+  ** at least one row of the right table has matched the left table.  
   */
-  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
-  if( nIdx>0 ){
-    aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
-    if( aRegIdx==0 ) goto update_cleanup;
+  if( pLevel->iLeftJoin ){
+    pLevel->addrFirst = sqlite3VdbeCurrentAddr(v);
+    sqlite3VdbeAddOp2(v, OP_Integer, 1, pLevel->iLeftJoin);
+    VdbeComment((v, "record LEFT JOIN hit"));
+    sqlite3ExprCacheClear(pParse);
+    for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
+      testcase( pTerm->wtFlags & TERM_VIRTUAL );
+      testcase( pTerm->wtFlags & TERM_CODED );
+      if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
+      if( (pTerm->prereqAll & notReady)!=0 ) continue;
+      assert( pTerm->pExpr );
+      sqlite3ExprIfFalse(pParse, pTerm->pExpr, addrCont, SQLITE_JUMPIFNULL);
+      pTerm->wtFlags |= TERM_CODED;
+    }
   }
-  for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
-    int reg;
-    if( chngRowid ){
-      reg = ++pParse->nMem;
-    }else{
-      reg = 0;
-      for(i=0; i<pIdx->nColumn; i++){
-        if( aXRef[pIdx->aiColumn[i]]>=0 ){
-          reg = ++pParse->nMem;
-          break;
+  sqlite3ReleaseTempReg(pParse, iReleaseReg);
+
+  return notReady;
+}
+
+#if defined(SQLITE_TEST)
+/*
+** The following variable holds a text description of query plan generated
+** by the most recent call to sqlite3WhereBegin().  Each call to WhereBegin
+** overwrites the previous.  This information is used for testing and
+** analysis only.
+*/
+SQLITE_API char sqlite3_query_plan[BMS*2*40];  /* Text of the join */
+static int nQPlan = 0;              /* Next free slow in _query_plan[] */
+
+#endif /* SQLITE_TEST */
+
+
+/*
+** Free a WhereInfo structure
+*/
+static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
+  if( pWInfo ){
+    int i;
+    for(i=0; i<pWInfo->nLevel; i++){
+      sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
+      if( pInfo ){
+        /* assert( pInfo->needToFreeIdxStr==0 || db->mallocFailed ); */
+        if( pInfo->needToFreeIdxStr ){
+          sqlite3_free(pInfo->idxStr);
         }
+        sqlite3DbFree(db, pInfo);
       }
     }
-    aRegIdx[j] = reg;
+    whereClauseClear(pWInfo->pWC);
+    sqlite3DbFree(db, pWInfo);
   }
+}
 
-  /* Allocate a block of register used to store the change record
-  ** sent to sqlite3GenerateConstraintChecks().  There are either
-  ** one or two registers for holding the rowid.  One rowid register
-  ** is used if chngRowid is false and two are used if chngRowid is
-  ** true.  Following these are pTab->nCol register holding column
-  ** data.
+
+/*
+** Generate the beginning of the loop used for WHERE clause processing.
+** The return value is a pointer to an opaque structure that contains
+** information needed to terminate the loop.  Later, the calling routine
+** should invoke sqlite3WhereEnd() with the return value of this function
+** in order to complete the WHERE clause processing.
+**
+** If an error occurs, this routine returns NULL.
+**
+** The basic idea is to do a nested loop, one loop for each table in
+** the FROM clause of a select.  (INSERT and UPDATE statements are the
+** same as a SELECT with only a single table in the FROM clause.)  For
+** example, if the SQL is this:
+**
+**       SELECT * FROM t1, t2, t3 WHERE ...;
+**
+** Then the code generated is conceptually like the following:
+**
+**      foreach row1 in t1 do       \    Code generated
+**        foreach row2 in t2 do      |-- by sqlite3WhereBegin()
+**          foreach row3 in t3 do   /
+**            ...
+**          end                     \    Code generated
+**        end                        |-- by sqlite3WhereEnd()
+**      end                         /
+**
+** Note that the loops might not be nested in the order in which they
+** appear in the FROM clause if a different order is better able to make
+** use of indices.  Note also that when the IN operator appears in
+** the WHERE clause, it might result in additional nested loops for
+** scanning through all values on the right-hand side of the IN.
+**
+** There are Btree cursors associated with each table.  t1 uses cursor
+** number pTabList->a[0].iCursor.  t2 uses the cursor pTabList->a[1].iCursor.
+** And so forth.  This routine generates code to open those VDBE cursors
+** and sqlite3WhereEnd() generates the code to close them.
+**
+** The code that sqlite3WhereBegin() generates leaves the cursors named
+** in pTabList pointing at their appropriate entries.  The [...] code
+** can use OP_Column and OP_Rowid opcodes on these cursors to extract
+** data from the various tables of the loop.
+**
+** If the WHERE clause is empty, the foreach loops must each scan their
+** entire tables.  Thus a three-way join is an O(N^3) operation.  But if
+** the tables have indices and there are terms in the WHERE clause that
+** refer to those indices, a complete table scan can be avoided and the
+** code will run much faster.  Most of the work of this routine is checking
+** to see if there are indices that can be used to speed up the loop.
+**
+** Terms of the WHERE clause are also used to limit which rows actually
+** make it to the "..." in the middle of the loop.  After each "foreach",
+** terms of the WHERE clause that use only terms in that loop and outer
+** loops are evaluated and if false a jump is made around all subsequent
+** inner loops (or around the "..." if the test occurs within the inner-
+** most loop)
+**
+** OUTER JOINS
+**
+** An outer join of tables t1 and t2 is conceptally coded as follows:
+**
+**    foreach row1 in t1 do
+**      flag = 0
+**      foreach row2 in t2 do
+**        start:
+**          ...
+**          flag = 1
+**      end
+**      if flag==0 then
+**        move the row2 cursor to a null row
+**        goto start
+**      fi
+**    end
+**
+** ORDER BY CLAUSE PROCESSING
+**
+** *ppOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
+** if there is one.  If there is no ORDER BY clause or if this routine
+** is called from an UPDATE or DELETE statement, then ppOrderBy is NULL.
+**
+** If an index can be used so that the natural output order of the table
+** scan is correct for the ORDER BY clause, then that index is used and
+** *ppOrderBy is set to NULL.  This is an optimization that prevents an
+** unnecessary sort of the result set if an index appropriate for the
+** ORDER BY clause already exists.
+**
+** If the where clause loops cannot be arranged to provide the correct
+** output order, then the *ppOrderBy is unchanged.
+*/
+SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
+  Parse *pParse,        /* The parser context */
+  SrcList *pTabList,    /* A list of all tables to be scanned */
+  Expr *pWhere,         /* The WHERE clause */
+  ExprList **ppOrderBy, /* An ORDER BY clause, or NULL */
+  u16 wctrlFlags        /* One of the WHERE_* flags defined in sqliteInt.h */
+){
+  int i;                     /* Loop counter */
+  int nByteWInfo;            /* Num. bytes allocated for WhereInfo struct */
+  WhereInfo *pWInfo;         /* Will become the return value of this function */
+  Vdbe *v = pParse->pVdbe;   /* The virtual database engine */
+  Bitmask notReady;          /* Cursors that are not yet positioned */
+  WhereMaskSet *pMaskSet;    /* The expression mask set */
+  WhereClause *pWC;               /* Decomposition of the WHERE clause */
+  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
+  WhereLevel *pLevel;             /* A single level in the pWInfo list */
+  int iFrom;                      /* First unused FROM clause element */
+  int andFlags;              /* AND-ed combination of all pWC->a[].wtFlags */
+  sqlite3 *db;               /* Database connection */
+
+  /* The number of tables in the FROM clause is limited by the number of
+  ** bits in a Bitmask 
   */
-  regOldRowid = regNewRowid = pParse->nMem + 1;
-  pParse->nMem += pTab->nCol + 1;
-  if( chngRowid ){
-    regNewRowid++;
-    pParse->nMem++;
+  if( pTabList->nSrc>BMS ){
+    sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
+    return 0;
   }
-  regData = regNewRowid+1;
- 
 
-  /* Begin generating code.
+  /* Allocate and initialize the WhereInfo structure that will become the
+  ** return value. A single allocation is used to store the WhereInfo
+  ** struct, the contents of WhereInfo.a[], the WhereClause structure
+  ** and the WhereMaskSet structure. Since WhereClause contains an 8-byte
+  ** field (type Bitmask) it must be aligned on an 8-byte boundary on
+  ** some architectures. Hence the ROUND8() below.
   */
-  v = sqlite3GetVdbe(pParse);
-  if( v==0 ) goto update_cleanup;
-  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
-  sqlite3BeginWriteOperation(pParse, 1, iDb);
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  /* Virtual tables must be handled separately */
-  if( IsVirtual(pTab) ){
-    updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
-                       pWhere);
-    pWhere = 0;
-    pTabList = 0;
-    goto update_cleanup;
+  db = pParse->db;
+  nByteWInfo = ROUND8(sizeof(WhereInfo)+(pTabList->nSrc-1)*sizeof(WhereLevel));
+  pWInfo = sqlite3DbMallocZero(db, 
+      nByteWInfo + 
+      sizeof(WhereClause) +
+      sizeof(WhereMaskSet)
+  );
+  if( db->mallocFailed ){
+    goto whereBeginError;
   }
-#endif
+  pWInfo->nLevel = pTabList->nSrc;
+  pWInfo->pParse = pParse;
+  pWInfo->pTabList = pTabList;
+  pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
+  pWInfo->pWC = pWC = (WhereClause *)&((u8 *)pWInfo)[nByteWInfo];
+  pWInfo->wctrlFlags = wctrlFlags;
+  pMaskSet = (WhereMaskSet*)&pWC[1];
 
-  /* Start the view context
+  /* Split the WHERE clause into separate subexpressions where each
+  ** subexpression is separated by an AND operator.
   */
-  if( isView ){
-    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
+  initMaskSet(pMaskSet);
+  whereClauseInit(pWC, pParse, pMaskSet);
+  sqlite3ExprCodeConstants(pParse, pWhere);
+  whereSplit(pWC, pWhere, TK_AND);
+    
+  /* Special case: a WHERE clause that is constant.  Evaluate the
+  ** expression and either jump over all of the code or fall thru.
+  */
+  if( pWhere && (pTabList->nSrc==0 || sqlite3ExprIsConstantNotJoin(pWhere)) ){
+    sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, SQLITE_JUMPIFNULL);
+    pWhere = 0;
   }
 
-  /* Generate the code for triggers.
+  /* Assign a bit from the bitmask to every term in the FROM clause.
+  **
+  ** When assigning bitmask values to FROM clause cursors, it must be
+  ** the case that if X is the bitmask for the N-th FROM clause term then
+  ** the bitmask for all FROM clause terms to the left of the N-th term
+  ** is (X-1).   An expression from the ON clause of a LEFT JOIN can use
+  ** its Expr.iRightJoinTable value to find the bitmask of the right table
+  ** of the join.  Subtracting one from the right table bitmask gives a
+  ** bitmask for all tables to the left of the join.  Knowing the bitmask
+  ** for all tables to the left of a left join is important.  Ticket #3015.
+  **
+  ** Configure the WhereClause.vmask variable so that bits that correspond
+  ** to virtual table cursors are set. This is used to selectively disable 
+  ** the OR-to-IN transformation in exprAnalyzeOrTerm(). It is not helpful 
+  ** with virtual tables.
   */
-  if( triggers_exist ){
-    int iGoto;
-
-    /* Create pseudo-tables for NEW and OLD
-    */
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
-    sqlite3VdbeAddOp2(v, OP_OpenPseudo, oldIdx, 0);
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
-    sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
-
-    iGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    addr = sqlite3VdbeMakeLabel(v);
-    iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
-    if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
-          newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
-      goto update_cleanup;
-    }
-    iEndBeforeTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
-    if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab, 
-          newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
-      goto update_cleanup;
+  assert( pWC->vmask==0 && pMaskSet->n==0 );
+  for(i=0; i<pTabList->nSrc; i++){
+    createMask(pMaskSet, pTabList->a[i].iCursor);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( ALWAYS(pTabList->a[i].pTab) && IsVirtual(pTabList->a[i].pTab) ){
+      pWC->vmask |= ((Bitmask)1 << i);
     }
-    iEndAfterTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    sqlite3VdbeJumpHere(v, iGoto);
+#endif
   }
-
-  /* If we are trying to update a view, realize that view into
-  ** a ephemeral table.
-  */
-  if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
+#ifndef NDEBUG
+  {
+    Bitmask toTheLeft = 0;
+    for(i=0; i<pTabList->nSrc; i++){
+      Bitmask m = getMask(pMaskSet, pTabList->a[i].iCursor);
+      assert( (m-1)==toTheLeft );
+      toTheLeft |= m;
+    }
   }
+#endif
 
-  /* Resolve the column names in all the expressions in the
-  ** WHERE clause.
+  /* Analyze all of the subexpressions.  Note that exprAnalyze() might
+  ** add new virtual terms onto the end of the WHERE clause.  We do not
+  ** want to analyze these virtual terms, so start analyzing at the end
+  ** and work forward so that the added virtual terms are never processed.
   */
-  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
-    goto update_cleanup;
+  exprAnalyzeAll(pTabList, pWC);
+  if( db->mallocFailed ){
+    goto whereBeginError;
   }
 
-  /* Begin the database scan
-  */
-  sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
-  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0,
-                             WHERE_ONEPASS_DESIRED);
-  if( pWInfo==0 ) goto update_cleanup;
-  okOnePass = pWInfo->okOnePass;
-
-  /* Remember the rowid of every item to be updated.
-  */
-  sqlite3VdbeAddOp2(v, IsVirtual(pTab)?OP_VRowid:OP_Rowid, iCur, regOldRowid);
-  if( !okOnePass ) sqlite3VdbeAddOp2(v, OP_FifoWrite, regOldRowid, 0);
-
-  /* End the database scan loop.
+  /* Chose the best index to use for each table in the FROM clause.
+  **
+  ** This loop fills in the following fields:
+  **
+  **   pWInfo->a[].pIdx      The index to use for this level of the loop.
+  **   pWInfo->a[].wsFlags   WHERE_xxx flags associated with pIdx
+  **   pWInfo->a[].nEq       The number of == and IN constraints
+  **   pWInfo->a[].iFrom     Which term of the FROM clause is being coded
+  **   pWInfo->a[].iTabCur   The VDBE cursor for the database table
+  **   pWInfo->a[].iIdxCur   The VDBE cursor for the index
+  **   pWInfo->a[].pTerm     When wsFlags==WO_OR, the OR-clause term
+  **
+  ** This loop also figures out the nesting order of tables in the FROM
+  ** clause.
   */
-  sqlite3WhereEnd(pWInfo);
+  notReady = ~(Bitmask)0;
+  pTabItem = pTabList->a;
+  pLevel = pWInfo->a;
+  andFlags = ~0;
+  WHERETRACE(("*** Optimizer Start ***\n"));
+  for(i=iFrom=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
+    WhereCost bestPlan;         /* Most efficient plan seen so far */
+    Index *pIdx;                /* Index for FROM table at pTabItem */
+    int j;                      /* For looping over FROM tables */
+    int bestJ = -1;             /* The value of j */
+    Bitmask m;                  /* Bitmask value for j or bestJ */
+    int isOptimal;              /* Iterator for optimal/non-optimal search */
 
-  /* Initialize the count of updated rows
-  */
-  if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
-    regRowCount = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
-  }
+    memset(&bestPlan, 0, sizeof(bestPlan));
+    bestPlan.rCost = SQLITE_BIG_DBL;
 
-  if( !isView && !IsVirtual(pTab) ){
-    /* 
-    ** Open every index that needs updating.  Note that if any
-    ** index could potentially invoke a REPLACE conflict resolution 
-    ** action, then we need to open all indices because we might need
-    ** to be deleting some records.
+    /* Loop through the remaining entries in the FROM clause to find the
+    ** next nested loop. The FROM clause entries may be iterated through
+    ** either once or twice. 
+    **
+    ** The first iteration, which is always performed, searches for the
+    ** FROM clause entry that permits the lowest-cost, "optimal" scan. In
+    ** this context an optimal scan is one that uses the same strategy
+    ** for the given FROM clause entry as would be selected if the entry
+    ** were used as the innermost nested loop.  In other words, a table
+    ** is chosen such that the cost of running that table cannot be reduced
+    ** by waiting for other tables to run first.
+    **
+    ** The second iteration is only performed if no optimal scan strategies
+    ** were found by the first. This iteration is used to search for the
+    ** lowest cost scan overall.
+    **
+    ** Previous versions of SQLite performed only the second iteration -
+    ** the next outermost loop was always that with the lowest overall
+    ** cost. However, this meant that SQLite could select the wrong plan
+    ** for scripts such as the following:
+    **   
+    **   CREATE TABLE t1(a, b); 
+    **   CREATE TABLE t2(c, d);
+    **   SELECT * FROM t2, t1 WHERE t2.rowid = t1.a;
+    **
+    ** The best strategy is to iterate through table t1 first. However it
+    ** is not possible to determine this with a simple greedy algorithm.
+    ** However, since the cost of a linear scan through table t2 is the same 
+    ** as the cost of a linear scan through table t1, a simple greedy 
+    ** algorithm may choose to use t2 for the outer loop, which is a much
+    ** costlier approach.
     */
-    if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); 
-    if( onError==OE_Replace ){
-      openAll = 1;
-    }else{
-      openAll = 0;
-      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
-        if( pIdx->onError==OE_Replace ){
-          openAll = 1;
-          break;
+    for(isOptimal=1; isOptimal>=0 && bestJ<0; isOptimal--){
+      Bitmask mask = (isOptimal ? 0 : notReady);
+      assert( (pTabList->nSrc-iFrom)>1 || isOptimal );
+      for(j=iFrom, pTabItem=&pTabList->a[j]; j<pTabList->nSrc; j++, pTabItem++){
+        int doNotReorder;    /* True if this table should not be reordered */
+        WhereCost sCost;     /* Cost information from best[Virtual]Index() */
+        ExprList *pOrderBy;  /* ORDER BY clause for index to optimize */
+  
+        doNotReorder =  (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0;
+        if( j!=iFrom && doNotReorder ) break;
+        m = getMask(pMaskSet, pTabItem->iCursor);
+        if( (m & notReady)==0 ){
+          if( j==iFrom ) iFrom++;
+          continue;
+        }
+        pOrderBy = ((i==0 && ppOrderBy )?*ppOrderBy:0);
+  
+        assert( pTabItem->pTab );
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+        if( IsVirtual(pTabItem->pTab) ){
+          sqlite3_index_info **pp = &pWInfo->a[j].pIdxInfo;
+          bestVirtualIndex(pParse, pWC, pTabItem, mask, pOrderBy, &sCost, pp);
+        }else 
+#endif
+        {
+          bestBtreeIndex(pParse, pWC, pTabItem, mask, pOrderBy, &sCost);
+        }
+        assert( isOptimal || (sCost.used&notReady)==0 );
+
+        if( (sCost.used&notReady)==0
+         && (j==iFrom || sCost.rCost<bestPlan.rCost) 
+        ){
+          bestPlan = sCost;
+          bestJ = j;
         }
+        if( doNotReorder ) break;
       }
     }
-    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
-      if( openAll || aRegIdx[i]>0 ){
-        KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
-        sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
-                       (char*)pKey, P4_KEYINFO_HANDOFF);
-        assert( pParse->nTab>iCur+i+1 );
-      }
+    assert( bestJ>=0 );
+    assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) );
+    WHERETRACE(("*** Optimizer selects table %d for loop %d\n", bestJ,
+           pLevel-pWInfo->a));
+    if( (bestPlan.plan.wsFlags & WHERE_ORDERBY)!=0 ){
+      *ppOrderBy = 0;
     }
-  }
-  
-  /* Jump back to this point if a trigger encounters an IGNORE constraint. */
-  if( triggers_exist ){
-    sqlite3VdbeResolveLabel(v, addr);
-  }
-
-  /* Top of the update loop */
-  if( okOnePass ){
-    int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
-    addr = sqlite3VdbeAddOp0(v, OP_Goto);
-    sqlite3VdbeJumpHere(v, a1);
-  }else{
-    addr = sqlite3VdbeAddOp2(v, OP_FifoRead, regOldRowid, 0);
-  }
-
-  if( triggers_exist ){
-    int regRowid;
-    int regRow;
-    int regCols;
-
-    /* Make cursor iCur point to the record that is being updated.
-    */
-    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
-
-    /* Generate the OLD table
-    */
-    regRowid = sqlite3GetTempReg(pParse);
-    regRow = sqlite3GetTempReg(pParse);
-    sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
-    if( !old_col_mask ){
-      sqlite3VdbeAddOp2(v, OP_Null, 0, regRow);
+    andFlags &= bestPlan.plan.wsFlags;
+    pLevel->plan = bestPlan.plan;
+    if( bestPlan.plan.wsFlags & WHERE_INDEXED ){
+      pLevel->iIdxCur = pParse->nTab++;
     }else{
-      sqlite3VdbeAddOp2(v, OP_RowData, iCur, regRow);
+      pLevel->iIdxCur = -1;
     }
-    sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, regRow, regRowid);
+    notReady &= ~getMask(pMaskSet, pTabList->a[bestJ].iCursor);
+    pLevel->iFrom = (u8)bestJ;
 
-    /* Generate the NEW table
+    /* Check that if the table scanned by this loop iteration had an
+    ** INDEXED BY clause attached to it, that the named index is being
+    ** used for the scan. If not, then query compilation has failed.
+    ** Return an error.
     */
-    if( chngRowid ){
-      sqlite3ExprCodeAndCache(pParse, pRowidExpr, regRowid);
-    }else{
-      sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
-    }
-    regCols = sqlite3GetTempRange(pParse, pTab->nCol);
-    for(i=0; i<pTab->nCol; i++){
-      if( i==pTab->iPKey ){
-        sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
-        continue;
-      }
-      j = aXRef[i];
-      if( new_col_mask&((u32)1<<i) || new_col_mask==0xffffffff ){
-        if( j<0 ){
-          sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regCols+i);
-          sqlite3ColumnDefault(v, pTab, i);
-        }else{
-          sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr, regCols+i);
-        }
+    pIdx = pTabList->a[bestJ].pIndex;
+    if( pIdx ){
+      if( (bestPlan.plan.wsFlags & WHERE_INDEXED)==0 ){
+        sqlite3ErrorMsg(pParse, "cannot use index: %s", pIdx->zName);
+        goto whereBeginError;
       }else{
-        sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
+        /* If an INDEXED BY clause is used, the bestIndex() function is
+        ** guaranteed to find the index specified in the INDEXED BY clause
+        ** if it find an index at all. */
+        assert( bestPlan.plan.u.pIdx==pIdx );
       }
     }
-    sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRow);
-    if( !isView ){
-      sqlite3TableAffinityStr(v, pTab);
-      sqlite3ExprCacheAffinityChange(pParse, regCols, pTab->nCol);
-    }
-    sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
-    if( pParse->nErr ) goto update_cleanup;
-    sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRow, regRowid);
-    sqlite3ReleaseTempReg(pParse, regRowid);
-    sqlite3ReleaseTempReg(pParse, regRow);
+  }
+  WHERETRACE(("*** Optimizer Finished ***\n"));
+  if( pParse->nErr || db->mallocFailed ){
+    goto whereBeginError;
+  }
 
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
-    sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
+  /* If the total query only selects a single row, then the ORDER BY
+  ** clause is irrelevant.
+  */
+  if( (andFlags & WHERE_UNIQUE)!=0 && ppOrderBy ){
+    *ppOrderBy = 0;
   }
 
-  if( !isView && !IsVirtual(pTab) ){
-    /* Loop over every record that needs updating.  We have to load
-    ** the old data for each record to be updated because some columns
-    ** might not change and we will need to copy the old value.
-    ** Also, the old data is needed to delete the old index entries.
-    ** So make the cursor point at the old record.
-    */
-    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
+  /* If the caller is an UPDATE or DELETE statement that is requesting
+  ** to use a one-pass algorithm, determine if this is appropriate.
+  ** The one-pass algorithm only works if the WHERE clause constraints
+  ** the statement to update a single row.
+  */
+  assert( (wctrlFlags & WHERE_ONEPASS_DESIRED)==0 || pWInfo->nLevel==1 );
+  if( (wctrlFlags & WHERE_ONEPASS_DESIRED)!=0 && (andFlags & WHERE_UNIQUE)!=0 ){
+    pWInfo->okOnePass = 1;
+    pWInfo->a[0].plan.wsFlags &= ~WHERE_IDX_ONLY;
+  }
 
-    /* If the record number will change, push the record number as it
-    ** will be after the update. (The old record number is currently
-    ** on top of the stack.)
-    */
-    if( chngRowid ){
-      sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
-      sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
-    }
+  /* Open all tables in the pTabList and any indices selected for
+  ** searching those tables.
+  */
+  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
+  for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
+    Table *pTab;     /* Table to open */
+    int iDb;         /* Index of database containing table/index */
 
-    /* Compute new data for this record.  
-    */
-    for(i=0; i<pTab->nCol; i++){
-      if( i==pTab->iPKey ){
-        sqlite3VdbeAddOp2(v, OP_Null, 0, regData+i);
-        continue;
+#ifndef SQLITE_OMIT_EXPLAIN
+    if( pParse->explain==2 ){
+      char *zMsg;
+      struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
+      zMsg = sqlite3MPrintf(db, "TABLE %s", pItem->zName);
+      if( pItem->zAlias ){
+        zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
       }
-      j = aXRef[i];
-      if( j<0 ){
-        sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regData+i);
-        sqlite3ColumnDefault(v, pTab, i);
-      }else{
-        sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regData+i);
+      if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
+        zMsg = sqlite3MAppendf(db, zMsg, "%s WITH INDEX %s",
+           zMsg, pLevel->plan.u.pIdx->zName);
+      }else if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
+        zMsg = sqlite3MAppendf(db, zMsg, "%s VIA MULTI-INDEX UNION", zMsg);
+      }else if( pLevel->plan.wsFlags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
+        zMsg = sqlite3MAppendf(db, zMsg, "%s USING PRIMARY KEY", zMsg);
+      }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+      else if( (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
+        sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
+        zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
+                    pVtabIdx->idxNum, pVtabIdx->idxStr);
+      }
+#endif
+      if( pLevel->plan.wsFlags & WHERE_ORDERBY ){
+        zMsg = sqlite3MAppendf(db, zMsg, "%s ORDER BY", zMsg);
       }
+      sqlite3VdbeAddOp4(v, OP_Explain, i, pLevel->iFrom, 0, zMsg, P4_DYNAMIC);
     }
-
-    /* Do constraint checks
-    */
-    sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
-                                    aRegIdx, chngRowid, 1,
-                                    onError, addr);
-
-    /* Delete the old indices for the current record.
-    */
-    j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
-    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
-
-    /* If changing the record number, delete the old record.
-    */
-    if( chngRowid ){
-      sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
+#endif /* SQLITE_OMIT_EXPLAIN */
+    pTabItem = &pTabList->a[pLevel->iFrom];
+    pTab = pTabItem->pTab;
+    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ) continue;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+    if( (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
+      const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
+      int iCur = pTabItem->iCursor;
+      sqlite3VdbeAddOp4(v, OP_VOpen, iCur, 0, 0, pVTab, P4_VTAB);
+    }else
+#endif
+    if( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
+         && (wctrlFlags & WHERE_OMIT_OPEN)==0 ){
+      int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
+      sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
+      if( !pWInfo->okOnePass && pTab->nCol<BMS ){
+        Bitmask b = pTabItem->colUsed;
+        int n = 0;
+        for(; b; b=b>>1, n++){}
+        sqlite3VdbeChangeP4(v, sqlite3VdbeCurrentAddr(v)-1, SQLITE_INT_TO_PTR(n), P4_INT32);
+        assert( n<=pTab->nCol );
+      }
+    }else{
+      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
     }
-    sqlite3VdbeJumpHere(v, j1);
-
-    /* Create the new index entries and the new record.
-    */
-    sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, 
-                             aRegIdx, chngRowid, 1, -1, 0);
-  }
-
-  /* Increment the row counter 
-  */
-  if( db->flags & SQLITE_CountRows && !pParse->trigStack){
-    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
+    pLevel->iTabCur = pTabItem->iCursor;
+    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
+      Index *pIx = pLevel->plan.u.pIdx;
+      KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
+      int iIdxCur = pLevel->iIdxCur;
+      assert( pIx->pSchema==pTab->pSchema );
+      assert( iIdxCur>=0 );
+      sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
+                        (char*)pKey, P4_KEYINFO_HANDOFF);
+      VdbeComment((v, "%s", pIx->zName));
+    }
+    sqlite3CodeVerifySchema(pParse, iDb);
   }
+  pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
 
-  /* If there are triggers, close all the cursors after each iteration
-  ** through the loop.  The fire the after triggers.
+  /* Generate the code to do the search.  Each iteration of the for
+  ** loop below generates code for a single nested loop of the VM
+  ** program.
   */
-  if( triggers_exist ){
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
-    sqlite3VdbeJumpHere(v, iEndAfterTrigger);
+  notReady = ~(Bitmask)0;
+  for(i=0; i<pTabList->nSrc; i++){
+    notReady = codeOneLoopStart(pWInfo, i, wctrlFlags, notReady);
+    pWInfo->iContinue = pWInfo->a[i].addrCont;
   }
 
-  /* Repeat the above with the next record to be updated, until
-  ** all record selected by the WHERE clause have been updated.
+#ifdef SQLITE_TEST  /* For testing and debugging use only */
+  /* Record in the query plan information about the current table
+  ** and the index used to access it (if any).  If the table itself
+  ** is not used, its name is just '{}'.  If no index is used
+  ** the index is listed as "{}".  If the primary key is used the
+  ** index name is '*'.
   */
-  sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
-  sqlite3VdbeJumpHere(v, addr);
-
-  /* Close all tables */
-  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
-    if( openAll || aRegIdx[i]>0 ){
-      sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
+  for(i=0; i<pTabList->nSrc; i++){
+    char *z;
+    int n;
+    pLevel = &pWInfo->a[i];
+    pTabItem = &pTabList->a[pLevel->iFrom];
+    z = pTabItem->zAlias;
+    if( z==0 ) z = pTabItem->pTab->zName;
+    n = sqlite3Strlen30(z);
+    if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){
+      if( pLevel->plan.wsFlags & WHERE_IDX_ONLY ){
+        memcpy(&sqlite3_query_plan[nQPlan], "{}", 2);
+        nQPlan += 2;
+      }else{
+        memcpy(&sqlite3_query_plan[nQPlan], z, n);
+        nQPlan += n;
+      }
+      sqlite3_query_plan[nQPlan++] = ' ';
+    }
+    testcase( pLevel->plan.wsFlags & WHERE_ROWID_EQ );
+    testcase( pLevel->plan.wsFlags & WHERE_ROWID_RANGE );
+    if( pLevel->plan.wsFlags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
+      memcpy(&sqlite3_query_plan[nQPlan], "* ", 2);
+      nQPlan += 2;
+    }else if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
+      n = sqlite3Strlen30(pLevel->plan.u.pIdx->zName);
+      if( n+nQPlan < sizeof(sqlite3_query_plan)-2 ){
+        memcpy(&sqlite3_query_plan[nQPlan], pLevel->plan.u.pIdx->zName, n);
+        nQPlan += n;
+        sqlite3_query_plan[nQPlan++] = ' ';
+      }
+    }else{
+      memcpy(&sqlite3_query_plan[nQPlan], "{} ", 3);
+      nQPlan += 3;
     }
   }
-  sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
-  if( triggers_exist ){
-    sqlite3VdbeAddOp2(v, OP_Close, newIdx, 0);
-    sqlite3VdbeAddOp2(v, OP_Close, oldIdx, 0);
+  while( nQPlan>0 && sqlite3_query_plan[nQPlan-1]==' ' ){
+    sqlite3_query_plan[--nQPlan] = 0;
   }
+  sqlite3_query_plan[nQPlan] = 0;
+  nQPlan = 0;
+#endif /* SQLITE_TEST // Testing and debugging use only */
 
-  /*
-  ** Return the number of rows that were changed. If this routine is 
-  ** generating code because of a call to sqlite3NestedParse(), do not
-  ** invoke the callback function.
+  /* Record the continuation address in the WhereInfo structure.  Then
+  ** clean up and return.
   */
-  if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
-    sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
-    sqlite3VdbeSetNumCols(v, 1);
-    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P4_STATIC);
-  }
+  return pWInfo;
 
-update_cleanup:
-  sqlite3AuthContextPop(&sContext);
-  sqlite3_free(aRegIdx);
-  sqlite3_free(aXRef);
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprListDelete(pChanges);
-  sqlite3ExprDelete(pWhere);
-  return;
+  /* Jump here if malloc fails */
+whereBeginError:
+  whereInfoFree(db, pWInfo);
+  return 0;
 }
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
 /*
-** Generate code for an UPDATE of a virtual table.
-**
-** The strategy is that we create an ephemerial table that contains
-** for each row to be changed:
-**
-**   (A)  The original rowid of that row.
-**   (B)  The revised rowid for the row. (note1)
-**   (C)  The content of every column in the row.
-**
-** Then we loop over this ephemeral table and for each row in
-** the ephermeral table call VUpdate.
-**
-** When finished, drop the ephemeral table.
-**
-** (note1) Actually, if we know in advance that (A) is always the same
-** as (B) we only store (A), then duplicate (A) when pulling
-** it out of the ephemeral table before calling VUpdate.
+** Generate the end of the WHERE loop.  See comments on 
+** sqlite3WhereBegin() for additional information.
 */
-static void updateVirtualTable(
-  Parse *pParse,       /* The parsing context */
-  SrcList *pSrc,       /* The virtual table to be modified */
-  Table *pTab,         /* The virtual table */
-  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
-  Expr *pRowid,        /* Expression used to recompute the rowid */
-  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
-  Expr *pWhere         /* WHERE clause of the UPDATE statement */
-){
-  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
-  ExprList *pEList = 0;     /* The result set of the SELECT statement */
-  Select *pSelect = 0;      /* The SELECT statement */
-  Expr *pExpr;              /* Temporary expression */
-  int ephemTab;             /* Table holding the result of the SELECT */
-  int i;                    /* Loop counter */
-  int addr;                 /* Address of top of loop */
-  int iReg;                 /* First register in set passed to OP_VUpdate */
-  sqlite3 *db = pParse->db; /* Database connection */
-  const char *pVtab = (const char*)pTab->pVtab;
-  SelectDest dest;
+SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
+  Parse *pParse = pWInfo->pParse;
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  WhereLevel *pLevel;
+  SrcList *pTabList = pWInfo->pTabList;
+  sqlite3 *db = pParse->db;
 
-  /* Construct the SELECT statement that will find the new values for
-  ** all updated rows. 
+  /* Generate loop termination code.
   */
-  pEList = sqlite3ExprListAppend(pParse, 0, 
-                                 sqlite3CreateIdExpr(pParse, "_rowid_"), 0);
-  if( pRowid ){
-    pEList = sqlite3ExprListAppend(pParse, pEList,
-                                   sqlite3ExprDup(db, pRowid), 0);
-  }
-  assert( pTab->iPKey<0 );
-  for(i=0; i<pTab->nCol; i++){
-    if( aXRef[i]>=0 ){
-      pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr);
-    }else{
-      pExpr = sqlite3CreateIdExpr(pParse, pTab->aCol[i].zName);
+  sqlite3ExprCacheClear(pParse);
+  for(i=pTabList->nSrc-1; i>=0; i--){
+    pLevel = &pWInfo->a[i];
+    sqlite3VdbeResolveLabel(v, pLevel->addrCont);
+    if( pLevel->op!=OP_Noop ){
+      sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2);
+      sqlite3VdbeChangeP5(v, pLevel->p5);
+    }
+    if( pLevel->plan.wsFlags & WHERE_IN_ABLE && pLevel->u.in.nIn>0 ){
+      struct InLoop *pIn;
+      int j;
+      sqlite3VdbeResolveLabel(v, pLevel->addrNxt);
+      for(j=pLevel->u.in.nIn, pIn=&pLevel->u.in.aInLoop[j-1]; j>0; j--, pIn--){
+        sqlite3VdbeJumpHere(v, pIn->addrInTop+1);
+        sqlite3VdbeAddOp2(v, OP_Next, pIn->iCur, pIn->addrInTop);
+        sqlite3VdbeJumpHere(v, pIn->addrInTop-1);
+      }
+      sqlite3DbFree(db, pLevel->u.in.aInLoop);
+    }
+    sqlite3VdbeResolveLabel(v, pLevel->addrBrk);
+    if( pLevel->iLeftJoin ){
+      int addr;
+      addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin);
+      sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);
+      if( pLevel->iIdxCur>=0 ){
+        sqlite3VdbeAddOp1(v, OP_NullRow, pLevel->iIdxCur);
+      }
+      if( pLevel->op==OP_Return ){
+        sqlite3VdbeAddOp2(v, OP_Gosub, pLevel->p1, pLevel->addrFirst);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrFirst);
+      }
+      sqlite3VdbeJumpHere(v, addr);
     }
-    pEList = sqlite3ExprListAppend(pParse, pEList, pExpr, 0);
   }
-  pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
-  
-  /* Create the ephemeral table into which the update results will
-  ** be stored.
+
+  /* The "break" point is here, just past the end of the outer loop.
+  ** Set it.
   */
-  assert( v );
-  ephemTab = pParse->nTab++;
-  sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
+  sqlite3VdbeResolveLabel(v, pWInfo->iBreak);
 
-  /* fill the ephemeral table 
+  /* Close all of the cursors that were opened by sqlite3WhereBegin.
   */
-  sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
-  sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
+  for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
+    struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
+    Table *pTab = pTabItem->pTab;
+    assert( pTab!=0 );
+    if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ) continue;
+    if( (pWInfo->wctrlFlags & WHERE_OMIT_CLOSE)==0 ){
+      if( !pWInfo->okOnePass && (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0 ){
+        sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
+      }
+      if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
+        sqlite3VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);
+      }
+    }
 
-  /* Generate code to scan the ephemeral table and call VUpdate. */
-  iReg = ++pParse->nMem;
-  pParse->nMem += pTab->nCol+1;
-  sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
-  addr = sqlite3VdbeCurrentAddr(v);
-  sqlite3VdbeAddOp3(v, OP_Column,  ephemTab, 0, iReg);
-  sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
-  for(i=0; i<pTab->nCol; i++){
-    sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
+    /* If this scan uses an index, make code substitutions to read data
+    ** from the index in preference to the table. Sometimes, this means
+    ** the table need never be read from. This is a performance boost,
+    ** as the vdbe level waits until the table is read before actually
+    ** seeking the table cursor to the record corresponding to the current
+    ** position in the index.
+    ** 
+    ** Calls to the code generator in between sqlite3WhereBegin and
+    ** sqlite3WhereEnd will have created code that references the table
+    ** directly.  This loop scans all that code looking for opcodes
+    ** that reference the table and converts them into opcodes that
+    ** reference the index.
+    */
+    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 && !db->mallocFailed){
+      int k, j, last;
+      VdbeOp *pOp;
+      Index *pIdx = pLevel->plan.u.pIdx;
+      int useIndexOnly = pLevel->plan.wsFlags & WHERE_IDX_ONLY;
+
+      assert( pIdx!=0 );
+      pOp = sqlite3VdbeGetOp(v, pWInfo->iTop);
+      last = sqlite3VdbeCurrentAddr(v);
+      for(k=pWInfo->iTop; k<last; k++, pOp++){
+        if( pOp->p1!=pLevel->iTabCur ) continue;
+        if( pOp->opcode==OP_Column ){
+          for(j=0; j<pIdx->nColumn; j++){
+            if( pOp->p2==pIdx->aiColumn[j] ){
+              pOp->p2 = j;
+              pOp->p1 = pLevel->iIdxCur;
+              break;
+            }
+          }
+          assert(!useIndexOnly || j<pIdx->nColumn);
+        }else if( pOp->opcode==OP_Rowid ){
+          pOp->p1 = pLevel->iIdxCur;
+          pOp->opcode = OP_IdxRowid;
+        }else if( pOp->opcode==OP_NullRow && useIndexOnly ){
+          pOp->opcode = OP_Noop;
+        }
+      }
+    }
   }
-  sqlite3VtabMakeWritable(pParse, pTab);
-  sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVtab, P4_VTAB);
-  sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr);
-  sqlite3VdbeJumpHere(v, addr-1);
-  sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
 
-  /* Cleanup */
-  sqlite3SelectDelete(pSelect);  
+  /* Final cleanup
+  */
+  whereInfoFree(db, pWInfo);
+  return;
 }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-/* Make sure "isView" gets undefined in case this file becomes part of
-** the amalgamation - so that subsequent files do not see isView as a
-** macro. */
-#undef isView
-
-/************** End of update.c **********************************************/
-/************** Begin file vacuum.c ******************************************/
-/*
-** 2003 April 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains code used to implement the VACUUM command.
-**
-** Most of the code in this file may be omitted by defining the
-** SQLITE_OMIT_VACUUM macro.
+/************** End of where.c ***********************************************/
+/************** Begin file parse.c *******************************************/
+/* Driver template for the LEMON parser generator.
+** The author disclaims copyright to this source code.
 **
-** $Id: vacuum.c,v 1.78 2008/04/30 16:38:23 drh Exp $
+** This version of "lempar.c" is modified, slightly, for use by SQLite.
+** The only modifications are the addition of a couple of NEVER()
+** macros to disable tests that are needed in the case of a general
+** LALR(1) grammar but which are always false in the
+** specific grammar used by SQLite.
 */
+/* First off, code is included that follows the "include" declaration
+** in the input grammar file. */
+
 
-#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
 /*
-** Execute zSql on database db. Return an error code.
+** Disable all error recovery processing in the parser push-down
+** automaton.
 */
-static int execSql(sqlite3 *db, const char *zSql){
-  sqlite3_stmt *pStmt;
-  if( !zSql ){
-    return SQLITE_NOMEM;
-  }
-  if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){
-    return sqlite3_errcode(db);
-  }
-  while( SQLITE_ROW==sqlite3_step(pStmt) ){}
-  return sqlite3_finalize(pStmt);
-}
+#define YYNOERRORRECOVERY 1
 
 /*
-** Execute zSql on database db. The statement returns exactly
-** one column. Execute this as SQL on the same database.
+** Make yytestcase() the same as testcase()
 */
-static int execExecSql(sqlite3 *db, const char *zSql){
-  sqlite3_stmt *pStmt;
-  int rc;
-
-  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
-  if( rc!=SQLITE_OK ) return rc;
+#define yytestcase(X) testcase(X)
 
-  while( SQLITE_ROW==sqlite3_step(pStmt) ){
-    rc = execSql(db, (char*)sqlite3_column_text(pStmt, 0));
-    if( rc!=SQLITE_OK ){
-      sqlite3_finalize(pStmt);
-      return rc;
-    }
-  }
+/*
+** An instance of this structure holds information about the
+** LIMIT clause of a SELECT statement.
+*/
+struct LimitVal {
+  Expr *pLimit;    /* The LIMIT expression.  NULL if there is no limit */
+  Expr *pOffset;   /* The OFFSET expression.  NULL if there is none */
+};
 
-  return sqlite3_finalize(pStmt);
-}
+/*
+** An instance of this structure is used to store the LIKE,
+** GLOB, NOT LIKE, and NOT GLOB operators.
+*/
+struct LikeOp {
+  Token eOperator;  /* "like" or "glob" or "regexp" */
+  int not;         /* True if the NOT keyword is present */
+};
 
 /*
-** The non-standard VACUUM command is used to clean up the database,
-** collapse free space, etc.  It is modelled after the VACUUM command
-** in PostgreSQL.
+** An instance of the following structure describes the event of a
+** TRIGGER.  "a" is the event type, one of TK_UPDATE, TK_INSERT,
+** TK_DELETE, or TK_INSTEAD.  If the event is of the form
 **
-** In version 1.0.x of SQLite, the VACUUM command would call
-** gdbm_reorganize() on all the database tables.  But beginning
-** with 2.0.0, SQLite no longer uses GDBM so this command has
-** become a no-op.
+**      UPDATE ON (a,b,c)
+**
+** Then the "b" IdList records the list "a,b,c".
 */
-SQLITE_PRIVATE void sqlite3Vacuum(Parse *pParse){
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v ){
-    sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0);
-  }
-  return;
-}
+struct TrigEvent { int a; IdList * b; };
 
 /*
-** This routine implements the OP_Vacuum opcode of the VDBE.
+** An instance of this structure holds the ATTACH key and the key type.
 */
-SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
-  int rc = SQLITE_OK;     /* Return code from service routines */
-  Btree *pMain;           /* The database being vacuumed */
-  Btree *pTemp;           /* The temporary database we vacuum into */
-  char *zSql = 0;         /* SQL statements */
-  int saved_flags;        /* Saved value of the db->flags */
-  Db *pDb = 0;            /* Database to detach at end of vacuum */
-  int nRes;
-
-  /* Save the current value of the write-schema flag before setting it. */
-  saved_flags = db->flags;
-  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
+struct AttachKey { int type;  Token key; };
 
-  if( !db->autoCommit ){
-    sqlite3SetString(pzErrMsg, "cannot VACUUM from within a transaction", 
-       (char*)0);
-    rc = SQLITE_ERROR;
-    goto end_of_vacuum;
-  }
-  pMain = db->aDb[0].pBt;
 
-  /* Attach the temporary database as 'vacuum_db'. The synchronous pragma
-  ** can be set to 'off' for this file, as it is not recovered if a crash
-  ** occurs anyway. The integrity of the database is maintained by a
-  ** (possibly synchronous) transaction opened on the main database before
-  ** sqlite3BtreeCopyFile() is called.
-  **
-  ** An optimisation would be to use a non-journaled pager.
-  ** (Later:) I tried setting "PRAGMA vacuum_db.journal_mode=OFF" but
-  ** that actually made the VACUUM run slower.  Very little journalling
-  ** actually occurs when doing a vacuum since the vacuum_db is initially
-  ** empty.  Only the journal header is written.  Apparently it takes more
-  ** time to parse and run the PRAGMA to turn journalling off than it does
-  ** to write the journal header file.
+  /* This is a utility routine used to set the ExprSpan.zStart and
+  ** ExprSpan.zEnd values of pOut so that the span covers the complete
+  ** range of text beginning with pStart and going to the end of pEnd.
   */
-  zSql = "ATTACH '' AS vacuum_db;";
-  rc = execSql(db, zSql);
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-  pDb = &db->aDb[db->nDb-1];
-  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
-  pTemp = db->aDb[db->nDb-1].pBt;
-
-  nRes = sqlite3BtreeGetReserve(pMain);
-  if( sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain), nRes)
-   || sqlite3BtreeSetPageSize(pTemp, db->nextPagesize, nRes)
-   || db->mallocFailed 
-  ){
-    rc = SQLITE_NOMEM;
-    goto end_of_vacuum;
-  }
-  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
-  if( rc!=SQLITE_OK ){
-    goto end_of_vacuum;
+  static void spanSet(ExprSpan *pOut, Token *pStart, Token *pEnd){
+    pOut->zStart = pStart->z;
+    pOut->zEnd = &pEnd->z[pEnd->n];
   }
 
-#ifndef SQLITE_OMIT_AUTOVACUUM
-  sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac>=0 ? db->nextAutovac :
-                                           sqlite3BtreeGetAutoVacuum(pMain));
-#endif
-
-  /* Begin a transaction */
-  rc = execSql(db, "BEGIN EXCLUSIVE;");
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-
-  /* Query the schema of the main database. Create a mirror schema
-  ** in the temporary database.
-  */
-  rc = execExecSql(db, 
-      "SELECT 'CREATE TABLE vacuum_db.' || substr(sql,14) "
-      "  FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'"
-      "   AND rootpage>0"
-  );
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-  rc = execExecSql(db, 
-      "SELECT 'CREATE INDEX vacuum_db.' || substr(sql,14)"
-      "  FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %' ");
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-  rc = execExecSql(db, 
-      "SELECT 'CREATE UNIQUE INDEX vacuum_db.' || substr(sql,21) "
-      "  FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %'");
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-
-  /* Loop through the tables in the main database. For each, do
-  ** an "INSERT INTO vacuum_db.xxx SELECT * FROM xxx;" to copy
-  ** the contents to the temporary database.
-  */
-  rc = execExecSql(db, 
-      "SELECT 'INSERT INTO vacuum_db.' || quote(name) "
-      "|| ' SELECT * FROM ' || quote(name) || ';'"
-      "FROM sqlite_master "
-      "WHERE type = 'table' AND name!='sqlite_sequence' "
-      "  AND rootpage>0"
-
-  );
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-
-  /* Copy over the sequence table
-  */
-  rc = execExecSql(db, 
-      "SELECT 'DELETE FROM vacuum_db.' || quote(name) || ';' "
-      "FROM vacuum_db.sqlite_master WHERE name='sqlite_sequence' "
-  );
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-  rc = execExecSql(db, 
-      "SELECT 'INSERT INTO vacuum_db.' || quote(name) "
-      "|| ' SELECT * FROM ' || quote(name) || ';' "
-      "FROM vacuum_db.sqlite_master WHERE name=='sqlite_sequence';"
-  );
-  if( rc!=SQLITE_OK ) goto end_of_vacuum;
-
-
-  /* Copy the triggers, views, and virtual tables from the main database
-  ** over to the temporary database.  None of these objects has any
-  ** associated storage, so all we have to do is copy their entries
-  ** from the SQLITE_MASTER table.
+  /* Construct a new Expr object from a single identifier.  Use the
+  ** new Expr to populate pOut.  Set the span of pOut to be the identifier
+  ** that created the expression.
   */
-  rc = execSql(db,
-      "INSERT INTO vacuum_db.sqlite_master "
-      "  SELECT type, name, tbl_name, rootpage, sql"
-      "    FROM sqlite_master"
-      "   WHERE type='view' OR type='trigger'"
-      "      OR (type='table' AND rootpage=0)"
-  );
-  if( rc ) goto end_of_vacuum;
+  static void spanExpr(ExprSpan *pOut, Parse *pParse, int op, Token *pValue){
+    pOut->pExpr = sqlite3PExpr(pParse, op, 0, 0, pValue);
+    pOut->zStart = pValue->z;
+    pOut->zEnd = &pValue->z[pValue->n];
+  }
 
-  /* At this point, unless the main db was completely empty, there is now a
-  ** transaction open on the vacuum database, but not on the main database.
-  ** Open a btree level transaction on the main database. This allows a
-  ** call to sqlite3BtreeCopyFile(). The main database btree level
-  ** transaction is then committed, so the SQL level never knows it was
-  ** opened for writing. This way, the SQL transaction used to create the
-  ** temporary database never needs to be committed.
+  /* This routine constructs a binary expression node out of two ExprSpan
+  ** objects and uses the result to populate a new ExprSpan object.
   */
-  if( rc==SQLITE_OK ){
-    u32 meta;
-    int i;
-
-    /* This array determines which meta meta values are preserved in the
-    ** vacuum.  Even entries are the meta value number and odd entries
-    ** are an increment to apply to the meta value after the vacuum.
-    ** The increment is used to increase the schema cookie so that other
-    ** connections to the same database will know to reread the schema.
-    */
-    static const unsigned char aCopy[] = {
-       1, 1,    /* Add one to the old schema cookie */
-       3, 0,    /* Preserve the default page cache size */
-       5, 0,    /* Preserve the default text encoding */
-       6, 0,    /* Preserve the user version */
-    };
-
-    assert( 1==sqlite3BtreeIsInTrans(pTemp) );
-    assert( 1==sqlite3BtreeIsInTrans(pMain) );
-
-    /* Copy Btree meta values */
-    for(i=0; i<sizeof(aCopy)/sizeof(aCopy[0]); i+=2){
-      rc = sqlite3BtreeGetMeta(pMain, aCopy[i], &meta);
-      if( rc!=SQLITE_OK ) goto end_of_vacuum;
-      rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]);
-      if( rc!=SQLITE_OK ) goto end_of_vacuum;
-    }
-
-    rc = sqlite3BtreeCopyFile(pMain, pTemp);
-    if( rc!=SQLITE_OK ) goto end_of_vacuum;
-    rc = sqlite3BtreeCommit(pTemp);
-    if( rc!=SQLITE_OK ) goto end_of_vacuum;
-    rc = sqlite3BtreeCommit(pMain);
+  static void spanBinaryExpr(
+    ExprSpan *pOut,     /* Write the result here */
+    Parse *pParse,      /* The parsing context.  Errors accumulate here */
+    int op,             /* The binary operation */
+    ExprSpan *pLeft,    /* The left operand */
+    ExprSpan *pRight    /* The right operand */
+  ){
+    pOut->pExpr = sqlite3PExpr(pParse, op, pLeft->pExpr, pRight->pExpr, 0);
+    pOut->zStart = pLeft->zStart;
+    pOut->zEnd = pRight->zEnd;
   }
 
-  if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeSetPageSize(pMain, sqlite3BtreeGetPageSize(pTemp), nRes);
+  /* Construct an expression node for a unary postfix operator
+  */
+  static void spanUnaryPostfix(
+    ExprSpan *pOut,        /* Write the new expression node here */
+    Parse *pParse,         /* Parsing context to record errors */
+    int op,                /* The operator */
+    ExprSpan *pOperand,    /* The operand */
+    Token *pPostOp         /* The operand token for setting the span */
+  ){
+    pOut->pExpr = sqlite3PExpr(pParse, op, pOperand->pExpr, 0, 0);
+    pOut->zStart = pOperand->zStart;
+    pOut->zEnd = &pPostOp->z[pPostOp->n];
+  }                           
+
+  /* Construct an expression node for a unary prefix operator
+  */
+  static void spanUnaryPrefix(
+    ExprSpan *pOut,        /* Write the new expression node here */
+    Parse *pParse,         /* Parsing context to record errors */
+    int op,                /* The operator */
+    ExprSpan *pOperand,    /* The operand */
+    Token *pPreOp         /* The operand token for setting the span */
+  ){
+    pOut->pExpr = sqlite3PExpr(pParse, op, pOperand->pExpr, 0, 0);
+    pOut->zStart = pPreOp->z;
+    pOut->zEnd = pOperand->zEnd;
   }
+/* Next is all token values, in a form suitable for use by makeheaders.
+** This section will be null unless lemon is run with the -m switch.
+*/
+/* 
+** These constants (all generated automatically by the parser generator)
+** specify the various kinds of tokens (terminals) that the parser
+** understands. 
+**
+** Each symbol here is a terminal symbol in the grammar.
+*/
+/* Make sure the INTERFACE macro is defined.
+*/
+#ifndef INTERFACE
+# define INTERFACE 1
+#endif
+/* The next thing included is series of defines which control
+** various aspects of the generated parser.
+**    YYCODETYPE         is the data type used for storing terminal
+**                       and nonterminal numbers.  "unsigned char" is
+**                       used if there are fewer than 250 terminals
+**                       and nonterminals.  "int" is used otherwise.
+**    YYNOCODE           is a number of type YYCODETYPE which corresponds
+**                       to no legal terminal or nonterminal number.  This
+**                       number is used to fill in empty slots of the hash 
+**                       table.
+**    YYFALLBACK         If defined, this indicates that one or more tokens
+**                       have fall-back values which should be used if the
+**                       original value of the token will not parse.
+**    YYACTIONTYPE       is the data type used for storing terminal
+**                       and nonterminal numbers.  "unsigned char" is
+**                       used if there are fewer than 250 rules and
+**                       states combined.  "int" is used otherwise.
+**    sqlite3ParserTOKENTYPE     is the data type used for minor tokens given 
+**                       directly to the parser from the tokenizer.
+**    YYMINORTYPE        is the data type used for all minor tokens.
+**                       This is typically a union of many types, one of
+**                       which is sqlite3ParserTOKENTYPE.  The entry in the union
+**                       for base tokens is called "yy0".
+**    YYSTACKDEPTH       is the maximum depth of the parser's stack.  If
+**                       zero the stack is dynamically sized using realloc()
+**    sqlite3ParserARG_SDECL     A static variable declaration for the %extra_argument
+**    sqlite3ParserARG_PDECL     A parameter declaration for the %extra_argument
+**    sqlite3ParserARG_STORE     Code to store %extra_argument into yypParser
+**    sqlite3ParserARG_FETCH     Code to extract %extra_argument from yypParser
+**    YYNSTATE           the combined number of states.
+**    YYNRULE            the number of rules in the grammar
+**    YYERRORSYMBOL      is the code number of the error symbol.  If not
+**                       defined, then do no error processing.
+*/
+#define YYCODETYPE unsigned char
+#define YYNOCODE 254
+#define YYACTIONTYPE unsigned short int
+#define YYWILDCARD 67
+#define sqlite3ParserTOKENTYPE Token
+typedef union {
+  int yyinit;
+  sqlite3ParserTOKENTYPE yy0;
+  Select* yy3;
+  ExprList* yy14;
+  SrcList* yy65;
+  struct LikeOp yy96;
+  Expr* yy132;
+  u8 yy186;
+  int yy328;
+  ExprSpan yy346;
+  struct TrigEvent yy378;
+  IdList* yy408;
+  struct {int value; int mask;} yy429;
+  TriggerStep* yy473;
+  struct LimitVal yy476;
+} YYMINORTYPE;
+#ifndef YYSTACKDEPTH
+#define YYSTACKDEPTH 100
+#endif
+#define sqlite3ParserARG_SDECL Parse *pParse;
+#define sqlite3ParserARG_PDECL ,Parse *pParse
+#define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
+#define sqlite3ParserARG_STORE yypParser->pParse = pParse
+#define YYNSTATE 629
+#define YYNRULE 329
+#define YYFALLBACK 1
+#define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
+#define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
+#define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)
 
-end_of_vacuum:
-  /* Restore the original value of db->flags */
-  db->flags = saved_flags;
+/* The yyzerominor constant is used to initialize instances of
+** YYMINORTYPE objects to zero. */
+static const YYMINORTYPE yyzerominor = { 0 };
 
-  /* Currently there is an SQL level transaction open on the vacuum
-  ** database. No locks are held on any other files (since the main file
-  ** was committed at the btree level). So it safe to end the transaction
-  ** by manually setting the autoCommit flag to true and detaching the
-  ** vacuum database. The vacuum_db journal file is deleted when the pager
-  ** is closed by the DETACH.
-  */
-  db->autoCommit = 1;
+/* Define the yytestcase() macro to be a no-op if is not already defined
+** otherwise.
+**
+** Applications can choose to define yytestcase() in the %include section
+** to a macro that can assist in verifying code coverage.  For production
+** code the yytestcase() macro should be turned off.  But it is useful
+** for testing.
+*/
+#ifndef yytestcase
+# define yytestcase(X)
+#endif
 
-  if( pDb ){
-    sqlite3BtreeClose(pDb->pBt);
-    pDb->pBt = 0;
-    pDb->pSchema = 0;
-  }
 
-  sqlite3ResetInternalSchema(db, 0);
+/* Next are the tables used to determine what action to take based on the
+** current state and lookahead token.  These tables are used to implement
+** functions that take a state number and lookahead value and return an
+** action integer.  
+**
+** Suppose the action integer is N.  Then the action is determined as
+** follows
+**
+**   0 <= N < YYNSTATE                  Shift N.  That is, push the lookahead
+**                                      token onto the stack and goto state N.
+**
+**   YYNSTATE <= N < YYNSTATE+YYNRULE   Reduce by rule N-YYNSTATE.
+**
+**   N == YYNSTATE+YYNRULE              A syntax error has occurred.
+**
+**   N == YYNSTATE+YYNRULE+1            The parser accepts its input.
+**
+**   N == YYNSTATE+YYNRULE+2            No such action.  Denotes unused
+**                                      slots in the yy_action[] table.
+**
+** The action table is constructed as a single large table named yy_action[].
+** Given state S and lookahead X, the action is computed as
+**
+**      yy_action[ yy_shift_ofst[S] + X ]
+**
+** If the index value yy_shift_ofst[S]+X is out of range or if the value
+** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
+** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
+** and that yy_default[S] should be used instead.  
+**
+** The formula above is for computing the action when the lookahead is
+** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
+** a reduce action) then the yy_reduce_ofst[] array is used in place of
+** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
+** YY_SHIFT_USE_DFLT.
+**
+** The following are the tables generated in this section:
+**
+**  yy_action[]        A single table containing all actions.
+**  yy_lookahead[]     A table containing the lookahead for each entry in
+**                     yy_action.  Used to detect hash collisions.
+**  yy_shift_ofst[]    For each state, the offset into yy_action for
+**                     shifting terminals.
+**  yy_reduce_ofst[]   For each state, the offset into yy_action for
+**                     shifting non-terminals after a reduce.
+**  yy_default[]       Default action for each state.
+*/
+static const YYACTIONTYPE yy_action[] = {
+ /*     0 */   312,  959,  182,  628,    2,  157,  219,  450,   24,   24,
+ /*    10 */    24,   24,  221,   26,   26,   26,   26,   27,   27,   28,
+ /*    20 */    28,   28,   29,  221,  424,  425,   30,  492,   33,  141,
+ /*    30 */   457,  463,   31,   26,   26,   26,   26,   27,   27,   28,
+ /*    40 */    28,   28,   29,  221,   28,   28,   28,   29,  221,   23,
+ /*    50 */    22,   32,  465,  466,  464,  464,   25,   25,   24,   24,
+ /*    60 */    24,   24,  293,   26,   26,   26,   26,   27,   27,   28,
+ /*    70 */    28,   28,   29,  221,  312,  450,  319,  479,  344,  208,
+ /*    80 */    47,   26,   26,   26,   26,   27,   27,   28,   28,   28,
+ /*    90 */    29,  221,  427,  428,  163,  339,  543,  368,  371,  372,
+ /*   100 */   521,  317,  472,  473,  457,  463,  296,  373,  294,   21,
+ /*   110 */   336,  367,  419,  416,  424,  425,  523,    1,  544,  446,
+ /*   120 */    80,  424,  425,   23,   22,   32,  465,  466,  464,  464,
+ /*   130 */    25,   25,   24,   24,   24,   24,  564,   26,   26,   26,
+ /*   140 */    26,   27,   27,   28,   28,   28,   29,  221,  312,  233,
+ /*   150 */   319,  441,  554,  152,  139,  263,  365,  268,  366,  160,
+ /*   160 */   551,  352,  332,  421,  222,  272,  362,  322,  218,  557,
+ /*   170 */   116,  339,  248,  574,  477,  223,  216,  573,  457,  463,
+ /*   180 */   450,   59,  427,  428,  295,  610,  336,  563,  538,  427,
+ /*   190 */   428,  385,  608,  609,  562,  446,   87,   23,   22,   32,
+ /*   200 */   465,  466,  464,  464,   25,   25,   24,   24,   24,   24,
+ /*   210 */   447,   26,   26,   26,   26,   27,   27,   28,   28,   28,
+ /*   220 */    29,  221,  312,  233,  477,  223,  576,  134,  139,  263,
+ /*   230 */   365,  268,  366,  160,  406,  354,  226,  498,  481,  272,
+ /*   240 */   339,   27,   27,   28,   28,   28,   29,  221,  450,  442,
+ /*   250 */   199,  540,  457,  463,  349,  336,  163,  551,   66,  368,
+ /*   260 */   371,  372,  450,  415,  446,   80,  522,  581,  401,  373,
+ /*   270 */   452,   23,   22,   32,  465,  466,  464,  464,   25,   25,
+ /*   280 */    24,   24,   24,   24,  447,   26,   26,   26,   26,   27,
+ /*   290 */    27,   28,   28,   28,   29,  221,  312,  339,  556,  607,
+ /*   300 */   197,  454,  454,  454,  546,  578,  352,  198,  607,  440,
+ /*   310 */    65,  351,  336,  426,  426,  399,  289,  424,  425,  606,
+ /*   320 */   605,  446,   73,  426,  214,  219,  457,  463,  606,  410,
+ /*   330 */   450,  241,  306,  196,  565,  479,  555,  208,  288,   29,
+ /*   340 */   221,  447,    4,  874,  504,   23,   22,   32,  465,  466,
+ /*   350 */   464,  464,   25,   25,   24,   24,   24,   24,  447,   26,
+ /*   360 */    26,   26,   26,   27,   27,   28,   28,   28,   29,  221,
+ /*   370 */   312,  163,  582,  339,  368,  371,  372,  314,  424,  425,
+ /*   380 */   604,  222,  397,  227,  373,  427,  428,  339,  336,  409,
+ /*   390 */   222,  478,  339,   30,  396,   33,  141,  446,   81,   62,
+ /*   400 */   457,  463,  336,  157,  400,  450,  504,  336,  438,  426,
+ /*   410 */   500,  446,   87,   41,  380,  613,  446,   80,  581,   23,
+ /*   420 */    22,   32,  465,  466,  464,  464,   25,   25,   24,   24,
+ /*   430 */    24,   24,  213,   26,   26,   26,   26,   27,   27,   28,
+ /*   440 */    28,   28,   29,  221,  312,  513,  427,  428,  517,  254,
+ /*   450 */   524,  386,  225,  339,  486,  363,  389,  339,  356,  443,
+ /*   460 */   494,  236,   30,  497,   33,  141,  399,  289,  336,  495,
+ /*   470 */   487,  501,  336,  450,  457,  463,  219,  446,   95,  445,
+ /*   480 */    68,  446,   95,  444,  424,  425,  488,   44,  348,  288,
+ /*   490 */   504,  424,  425,   23,   22,   32,  465,  466,  464,  464,
+ /*   500 */    25,   25,   24,   24,   24,   24,  391,   26,   26,   26,
+ /*   510 */    26,   27,   27,   28,   28,   28,   29,  221,  312,  361,
+ /*   520 */   556,  426,  520,  328,  191,  271,  339,  329,  247,  259,
+ /*   530 */   339,  566,   65,  249,  336,  426,  424,  425,  445,  516,
+ /*   540 */   426,  336,  444,  446,    9,  336,  556,  451,  457,  463,
+ /*   550 */   446,   74,  427,  428,  446,   69,  192,  618,   65,  427,
+ /*   560 */   428,  426,  323,  277,   16,  202,  189,   23,   22,   32,
+ /*   570 */   465,  466,  464,  464,   25,   25,   24,   24,   24,   24,
+ /*   580 */   255,   26,   26,   26,   26,   27,   27,   28,   28,   28,
+ /*   590 */    29,  221,  312,  339,  486,  426,  537,  235,  515,  447,
+ /*   600 */   339,  629,  419,  416,  427,  428,  217,  281,  336,  279,
+ /*   610 */   487,  203,  144,  526,  527,  336,  391,  446,   78,  429,
+ /*   620 */   430,  431,  457,  463,  446,   99,  488,  341,  528,  468,
+ /*   630 */   468,  426,  343,  472,  473,  626,  949,  474,  949,  529,
+ /*   640 */   447,   23,   22,   32,  465,  466,  464,  464,   25,   25,
+ /*   650 */    24,   24,   24,   24,  339,   26,   26,   26,   26,   27,
+ /*   660 */    27,   28,   28,   28,   29,  221,  312,  339,  162,  336,
+ /*   670 */   275,  283,  476,  376,  339,  579,  527,  346,  446,   98,
+ /*   680 */   622,   30,  336,   33,  141,  339,  426,  339,  508,  336,
+ /*   690 */   469,  446,  105,  418,    2,  222,  457,  463,  446,  101,
+ /*   700 */   336,  219,  336,  426,  161,  626,  948,  290,  948,  446,
+ /*   710 */   108,  446,  109,  398,  284,   23,   22,   32,  465,  466,
+ /*   720 */   464,  464,   25,   25,   24,   24,   24,   24,  339,   26,
+ /*   730 */    26,   26,   26,   27,   27,   28,   28,   28,   29,  221,
+ /*   740 */   312,  339,  271,  336,  339,   58,  535,  482,  143,  339,
+ /*   750 */   622,  318,  446,  133,  408,  257,  336,  426,  321,  336,
+ /*   760 */   357,  339,  272,  426,  336,  446,  135,  184,  446,   61,
+ /*   770 */   457,  463,  219,  446,  106,  426,  336,  493,  341,  234,
+ /*   780 */   468,  468,  621,  310,  407,  446,  102,  209,  144,   23,
+ /*   790 */    22,   32,  465,  466,  464,  464,   25,   25,   24,   24,
+ /*   800 */    24,   24,  339,   26,   26,   26,   26,   27,   27,   28,
+ /*   810 */    28,   28,   29,  221,  312,  339,  271,  336,  339,  341,
+ /*   820 */   538,  468,  468,  572,  383,  496,  446,   79,  499,  549,
+ /*   830 */   336,  426,  508,  336,  508,  341,  339,  468,  468,  446,
+ /*   840 */   103,  391,  446,   70,  457,  463,  572,  426,   40,  426,
+ /*   850 */    42,  336,  220,  324,  504,  341,  426,  468,  468,   18,
+ /*   860 */   446,  100,  266,   23,   22,   32,  465,  466,  464,  464,
+ /*   870 */    25,   25,   24,   24,   24,   24,  339,   26,   26,   26,
+ /*   880 */    26,   27,   27,   28,   28,   28,   29,  221,  312,  339,
+ /*   890 */   283,  336,  339,  261,  548,  384,  339,  327,  142,  550,
+ /*   900 */   446,  136,  475,  475,  336,  426,  185,  336,  499,  396,
+ /*   910 */   339,  336,  370,  446,  137,  256,  446,  138,  457,  463,
+ /*   920 */   446,   71,  499,  360,  426,  336,  161,  311,  623,  215,
+ /*   930 */   426,  359,  237,  412,  446,   82,  200,   23,   34,   32,
+ /*   940 */   465,  466,  464,  464,   25,   25,   24,   24,   24,   24,
+ /*   950 */   339,   26,   26,   26,   26,   27,   27,   28,   28,   28,
+ /*   960 */    29,  221,  312,  447,  271,  336,  339,  271,  340,  210,
+ /*   970 */   447,  172,  625,  211,  446,   83,  240,  552,  142,  426,
+ /*   980 */   321,  336,  426,  426,  339,  414,  331,  181,  458,  459,
+ /*   990 */   446,   72,  457,  463,  470,  506,   67,  158,  394,  336,
+ /*  1000 */   587,  325,  499,  447,  326,  311,  624,  447,  446,   84,
+ /*  1010 */   461,  462,   22,   32,  465,  466,  464,  464,   25,   25,
+ /*  1020 */    24,   24,   24,   24,  339,   26,   26,   26,   26,   27,
+ /*  1030 */    27,   28,   28,   28,   29,  221,  312,  460,  339,  336,
+ /*  1040 */   339,  283,  423,  393,  532,  533,  204,  205,  446,   85,
+ /*  1050 */   625,  392,  547,  336,  162,  336,  426,  426,  339,  435,
+ /*  1060 */   436,  339,  446,  104,  446,   86,  457,  463,  264,  291,
+ /*  1070 */   274,   49,  162,  336,  426,  426,  336,  297,  265,  542,
+ /*  1080 */   541,  405,  446,   88,  594,  446,   89,   32,  465,  466,
+ /*  1090 */   464,  464,   25,   25,   24,   24,   24,   24,  600,   26,
+ /*  1100 */    26,   26,   26,   27,   27,   28,   28,   28,   29,  221,
+ /*  1110 */    36,  345,  339,    3,  214,    8,  422,  335,  425,  437,
+ /*  1120 */   375,  148,  162,   36,  345,  339,    3,  336,  342,  432,
+ /*  1130 */   335,  425,  149,  577,  426,  162,  446,   90,  151,  339,
+ /*  1140 */   336,  342,  434,  339,  283,  433,  333,  347,  447,  446,
+ /*  1150 */    75,  588,    6,  158,  336,  448,  140,  481,  336,  426,
+ /*  1160 */   347,  453,  334,  446,   76,   49,  350,  446,   91,    7,
+ /*  1170 */   481,  426,  397,  283,  355,  250,  426,   39,   38,  251,
+ /*  1180 */   339,  426,   48,  353,   37,  337,  338,  596,  426,  452,
+ /*  1190 */    39,   38,  514,  252,  390,  336,   20,   37,  337,  338,
+ /*  1200 */   253,   43,  452,  206,  446,   92,  219,  449,  242,  243,
+ /*  1210 */   244,  150,  246,  283,  491,  593,  597,  490,  224,  258,
+ /*  1220 */   454,  454,  454,  455,  456,   10,  503,  183,  426,  178,
+ /*  1230 */   156,  301,  426,  454,  454,  454,  455,  456,   10,  339,
+ /*  1240 */   302,  426,   36,  345,   50,    3,  339,  505,  260,  335,
+ /*  1250 */   425,  262,  339,  176,  336,  581,  598,  358,  364,  175,
+ /*  1260 */   342,  336,  177,  446,   93,   46,  345,  336,    3,  339,
+ /*  1270 */   446,   94,  335,  425,  525,  339,  446,   77,  320,  347,
+ /*  1280 */   511,  339,  507,  342,  336,  589,  601,   56,   56,  481,
+ /*  1290 */   336,  512,  283,  446,   17,  531,  336,  426,  530,  446,
+ /*  1300 */    96,  534,  347,  404,  298,  446,   97,  426,  313,   39,
+ /*  1310 */    38,  267,  481,  219,  535,  536,   37,  337,  338,  283,
+ /*  1320 */   620,  452,  309,  283,  111,   19,  288,  509,  269,  424,
+ /*  1330 */   425,  539,   39,   38,  426,  238,  270,  411,  426,   37,
+ /*  1340 */   337,  338,  426,  426,  452,  558,  426,  307,  231,  276,
+ /*  1350 */   278,  426,  454,  454,  454,  455,  456,   10,  553,  280,
+ /*  1360 */   426,  559,  239,  230,  426,  426,  299,  282,  287,  481,
+ /*  1370 */   560,  388,  584,  232,  426,  454,  454,  454,  455,  456,
+ /*  1380 */    10,  561,  426,  426,  585,  395,  426,  426,  292,  194,
+ /*  1390 */   195,  592,  603,  300,  303,  308,  377,  522,  381,  426,
+ /*  1400 */   426,  452,  567,  426,  304,  617,  426,  426,  426,  426,
+ /*  1410 */   379,   53,  147,  165,  166,  167,  580,  212,  569,  426,
+ /*  1420 */   426,  285,  168,  570,  387,  120,  123,  187,  590,  402,
+ /*  1430 */   403,  125,  454,  454,  454,  330,  599,  614,  186,  126,
+ /*  1440 */   127,  128,  615,  616,   57,   60,  619,  107,  229,   64,
+ /*  1450 */   115,  420,  245,  130,  439,  180,  315,  207,  670,  316,
+ /*  1460 */   671,  467,  672,  153,  154,   35,  483,  471,  480,  188,
+ /*  1470 */   201,  155,  484,    5,  485,  489,   12,  502,   45,   11,
+ /*  1480 */   110,  145,  518,  519,  510,  228,   51,  112,  369,  273,
+ /*  1490 */   113,  159,  545,   52,  374,  114,  164,  265,  378,  190,
+ /*  1500 */   146,  568,  117,  158,  286,  382,  169,  119,   15,  583,
+ /*  1510 */   170,  171,  121,  586,  122,   54,   55,   13,  124,  591,
+ /*  1520 */   173,  174,  118,  575,  129,  595,  571,  131,   14,  132,
+ /*  1530 */   611,   63,  612,  193,  602,  179,  305,  413,  417,  960,
+ /*  1540 */   627,
+};
+static const YYCODETYPE yy_lookahead[] = {
+ /*     0 */    19,  142,  143,  144,  145,   24,  115,   26,   77,   78,
+ /*    10 */    79,   80,   92,   82,   83,   84,   85,   86,   87,   88,
+ /*    20 */    89,   90,   91,   92,   26,   27,  222,  223,  224,  225,
+ /*    30 */    49,   50,   81,   82,   83,   84,   85,   86,   87,   88,
+ /*    40 */    89,   90,   91,   92,   88,   89,   90,   91,   92,   68,
+ /*    50 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
+ /*    60 */    79,   80,   16,   82,   83,   84,   85,   86,   87,   88,
+ /*    70 */    89,   90,   91,   92,   19,   94,   19,  166,  167,  168,
+ /*    80 */    25,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*    90 */    91,   92,   94,   95,   96,  150,   36,   99,  100,  101,
+ /*   100 */   174,  169,  170,  171,   49,   50,   60,  109,   62,   54,
+ /*   110 */   165,   51,    1,    2,   26,   27,  174,   22,   58,  174,
+ /*   120 */   175,   26,   27,   68,   69,   70,   71,   72,   73,   74,
+ /*   130 */    75,   76,   77,   78,   79,   80,  186,   82,   83,   84,
+ /*   140 */    85,   86,   87,   88,   89,   90,   91,   92,   19,   92,
+ /*   150 */    19,  172,  173,   96,   97,   98,   99,  100,  101,  102,
+ /*   160 */   181,  216,  146,  147,  232,  108,  221,  107,  152,  186,
+ /*   170 */   154,  150,  195,   30,   86,   87,  160,   34,   49,   50,
+ /*   180 */    26,   52,   94,   95,  138,   97,  165,  181,  182,   94,
+ /*   190 */    95,   48,  104,  105,  188,  174,  175,   68,   69,   70,
+ /*   200 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
+ /*   210 */   194,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*   220 */    91,   92,   19,   92,   86,   87,   21,   24,   97,   98,
+ /*   230 */    99,  100,  101,  102,  218,  214,  215,  208,   66,  108,
+ /*   240 */   150,   86,   87,   88,   89,   90,   91,   92,   94,  173,
+ /*   250 */   160,  183,   49,   50,  191,  165,   96,  181,   22,   99,
+ /*   260 */   100,  101,   26,  247,  174,  175,   94,   57,   63,  109,
+ /*   270 */    98,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   280 */    77,   78,   79,   80,  194,   82,   83,   84,   85,   86,
+ /*   290 */    87,   88,   89,   90,   91,   92,   19,  150,  150,  150,
+ /*   300 */    25,  129,  130,  131,  183,  100,  216,  160,  150,  161,
+ /*   310 */   162,  221,  165,  165,  165,  105,  106,   26,   27,  170,
+ /*   320 */   171,  174,  175,  165,  160,  115,   49,   50,  170,  171,
+ /*   330 */    94,  148,  163,  185,  186,  166,  167,  168,  128,   91,
+ /*   340 */    92,  194,  196,  138,  166,   68,   69,   70,   71,   72,
+ /*   350 */    73,   74,   75,   76,   77,   78,   79,   80,  194,   82,
+ /*   360 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
+ /*   370 */    19,   96,   11,  150,   99,  100,  101,  155,   26,   27,
+ /*   380 */   231,  232,  218,  205,  109,   94,   95,  150,  165,  231,
+ /*   390 */   232,  166,  150,  222,  150,  224,  225,  174,  175,  235,
+ /*   400 */    49,   50,  165,   24,  240,   26,  166,  165,  153,  165,
+ /*   410 */   119,  174,  175,  136,  237,  244,  174,  175,   57,   68,
+ /*   420 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
+ /*   430 */    79,   80,  236,   82,   83,   84,   85,   86,   87,   88,
+ /*   440 */    89,   90,   91,   92,   19,  205,   94,   95,   23,  226,
+ /*   450 */   165,  229,  215,  150,   12,   88,  234,  150,  216,  174,
+ /*   460 */    32,  217,  222,   25,  224,  225,  105,  106,  165,   41,
+ /*   470 */    28,  119,  165,   94,   49,   50,  115,  174,  175,  112,
+ /*   480 */    22,  174,  175,  116,   26,   27,   44,  136,   46,  128,
+ /*   490 */   166,   26,   27,   68,   69,   70,   71,   72,   73,   74,
+ /*   500 */    75,   76,   77,   78,   79,   80,  150,   82,   83,   84,
+ /*   510 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  150,
+ /*   520 */   150,  165,   23,  220,  196,  150,  150,  220,  158,  205,
+ /*   530 */   150,  161,  162,  198,  165,  165,   26,   27,  112,   23,
+ /*   540 */   165,  165,  116,  174,  175,  165,  150,  166,   49,   50,
+ /*   550 */   174,  175,   94,   95,  174,  175,  118,  161,  162,   94,
+ /*   560 */    95,  165,  187,   16,   22,  160,   24,   68,   69,   70,
+ /*   570 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
+ /*   580 */   150,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*   590 */    91,   92,   19,  150,   12,  165,   23,  241,   88,  194,
+ /*   600 */   150,    0,    1,    2,   94,   95,  160,   60,  165,   62,
+ /*   610 */    28,  206,  207,  190,  191,  165,  150,  174,  175,    7,
+ /*   620 */     8,    9,   49,   50,  174,  175,   44,  111,   46,  113,
+ /*   630 */   114,  165,  169,  170,  171,   22,   23,  233,   25,   57,
+ /*   640 */   194,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   650 */    77,   78,   79,   80,  150,   82,   83,   84,   85,   86,
+ /*   660 */    87,   88,   89,   90,   91,   92,   19,  150,   25,  165,
+ /*   670 */    23,  150,  233,   19,  150,  190,  191,  228,  174,  175,
+ /*   680 */    67,  222,  165,  224,  225,  150,  165,  150,  150,  165,
+ /*   690 */    23,  174,  175,  144,  145,  232,   49,   50,  174,  175,
+ /*   700 */   165,  115,  165,  165,   50,   22,   23,  241,   25,  174,
+ /*   710 */   175,  174,  175,  127,  193,   68,   69,   70,   71,   72,
+ /*   720 */    73,   74,   75,   76,   77,   78,   79,   80,  150,   82,
+ /*   730 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
+ /*   740 */    19,  150,  150,  165,  150,   24,  103,   23,  150,  150,
+ /*   750 */    67,  213,  174,  175,   97,  209,  165,  165,  104,  165,
+ /*   760 */   150,  150,  108,  165,  165,  174,  175,   23,  174,  175,
+ /*   770 */    49,   50,  115,  174,  175,  165,  165,  177,  111,  187,
+ /*   780 */   113,  114,  250,  251,  127,  174,  175,  206,  207,   68,
+ /*   790 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
+ /*   800 */    79,   80,  150,   82,   83,   84,   85,   86,   87,   88,
+ /*   810 */    89,   90,   91,   92,   19,  150,  150,  165,  150,  111,
+ /*   820 */   182,  113,  114,  105,  106,  177,  174,  175,   25,  166,
+ /*   830 */   165,  165,  150,  165,  150,  111,  150,  113,  114,  174,
+ /*   840 */   175,  150,  174,  175,   49,   50,  128,  165,  135,  165,
+ /*   850 */   137,  165,  197,  187,  166,  111,  165,  113,  114,  204,
+ /*   860 */   174,  175,  177,   68,   69,   70,   71,   72,   73,   74,
+ /*   870 */    75,   76,   77,   78,   79,   80,  150,   82,   83,   84,
+ /*   880 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  150,
+ /*   890 */   150,  165,  150,  205,  177,  213,  150,  213,   95,  177,
+ /*   900 */   174,  175,  129,  130,  165,  165,   23,  165,   25,  150,
+ /*   910 */   150,  165,  178,  174,  175,  150,  174,  175,   49,   50,
+ /*   920 */   174,  175,  119,   19,  165,  165,   50,   22,   23,  160,
+ /*   930 */   165,   27,  241,  193,  174,  175,  160,   68,   69,   70,
+ /*   940 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
+ /*   950 */   150,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*   960 */    91,   92,   19,  194,  150,  165,  150,  150,  150,  160,
+ /*   970 */   194,   25,   67,  160,  174,  175,  217,  166,   95,  165,
+ /*   980 */   104,  165,  165,  165,  150,  245,  248,  249,   49,   50,
+ /*   990 */   174,  175,   49,   50,   23,   23,   25,   25,  242,  165,
+ /*  1000 */   199,  187,  119,  194,  187,   22,   23,  194,  174,  175,
+ /*  1010 */    71,   72,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*  1020 */    77,   78,   79,   80,  150,   82,   83,   84,   85,   86,
+ /*  1030 */    87,   88,   89,   90,   91,   92,   19,   98,  150,  165,
+ /*  1040 */   150,  150,  150,   19,    7,    8,  105,  106,  174,  175,
+ /*  1050 */    67,   27,   23,  165,   25,  165,  165,  165,  150,  150,
+ /*  1060 */   150,  150,  174,  175,  174,  175,   49,   50,   98,  242,
+ /*  1070 */    23,  125,   25,  165,  165,  165,  165,  209,  108,   97,
+ /*  1080 */    98,  209,  174,  175,  193,  174,  175,   70,   71,   72,
+ /*  1090 */    73,   74,   75,   76,   77,   78,   79,   80,  199,   82,
+ /*  1100 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
+ /*  1110 */    19,   20,  150,   22,  160,   22,  149,   26,   27,  150,
+ /*  1120 */    23,    6,   25,   19,   20,  150,   22,  165,   37,  149,
+ /*  1130 */    26,   27,  151,   23,  165,   25,  174,  175,  151,  150,
+ /*  1140 */   165,   37,   13,  150,  150,  149,  149,   56,  194,  174,
+ /*  1150 */   175,   23,   25,   25,  165,  194,  150,   66,  165,  165,
+ /*  1160 */    56,  150,  159,  174,  175,  125,  150,  174,  175,   76,
+ /*  1170 */    66,  165,  218,  150,  122,  199,  165,   86,   87,  200,
+ /*  1180 */   150,  165,  123,  121,   93,   94,   95,  193,  165,   98,
+ /*  1190 */    86,   87,   88,  201,  240,  165,  124,   93,   94,   95,
+ /*  1200 */   202,  135,   98,    5,  174,  175,  115,  203,   10,   11,
+ /*  1210 */    12,   13,   14,  150,  157,   17,  193,  150,  227,  210,
+ /*  1220 */   129,  130,  131,  132,  133,  134,  150,  157,  165,   31,
+ /*  1230 */   117,   33,  165,  129,  130,  131,  132,  133,  134,  150,
+ /*  1240 */    42,  165,   19,   20,  104,   22,  150,  211,  210,   26,
+ /*  1250 */    27,  210,  150,   55,  165,   57,  193,  120,  104,   61,
+ /*  1260 */    37,  165,   64,  174,  175,   19,   20,  165,   22,  150,
+ /*  1270 */   174,  175,   26,   27,  176,  150,  174,  175,   47,   56,
+ /*  1280 */   211,  150,  150,   37,  165,   23,   23,   25,   25,   66,
+ /*  1290 */   165,  211,  150,  174,  175,  184,  165,  165,  176,  174,
+ /*  1300 */   175,  178,   56,  105,  106,  174,  175,  165,  110,   86,
+ /*  1310 */    87,  176,   66,  115,  103,  176,   93,   94,   95,  150,
+ /*  1320 */    23,   98,   25,  150,   22,   22,  128,  150,  150,   26,
+ /*  1330 */    27,  150,   86,   87,  165,  193,  150,  139,  165,   93,
+ /*  1340 */    94,   95,  165,  165,   98,  150,  165,  179,   92,  150,
+ /*  1350 */   150,  165,  129,  130,  131,  132,  133,  134,  184,  150,
+ /*  1360 */   165,  176,  193,  230,  165,  165,  193,  150,  150,   66,
+ /*  1370 */   176,  150,  150,  230,  165,  129,  130,  131,  132,  133,
+ /*  1380 */   134,  176,  165,  165,  150,  150,  165,  165,  150,   86,
+ /*  1390 */    87,  150,  150,  150,  150,  179,   18,   94,   45,  165,
+ /*  1400 */   165,   98,  157,  165,  150,  150,  165,  165,  165,  165,
+ /*  1410 */   157,  135,   68,  156,  156,  156,  189,  157,  157,  165,
+ /*  1420 */   165,  238,  156,  239,  157,  189,   22,  219,  199,  157,
+ /*  1430 */    18,  192,  129,  130,  131,  157,  199,   40,  219,  192,
+ /*  1440 */   192,  192,  157,  157,  243,  243,   38,  164,  180,  246,
+ /*  1450 */   180,    1,   15,  189,   23,  249,  252,   22,  117,  252,
+ /*  1460 */   117,  112,  117,  117,  117,   22,   11,   23,   23,   22,
+ /*  1470 */    22,   25,   23,   35,   23,   23,   35,  119,   25,   25,
+ /*  1480 */    22,  117,   23,   23,   27,   52,   22,   22,   52,   23,
+ /*  1490 */    22,   35,   29,   22,   52,   22,  102,  108,   19,   24,
+ /*  1500 */    39,   20,  104,   25,  138,   43,  104,   22,    5,    1,
+ /*  1510 */   117,   35,  107,   27,  126,   76,   76,   22,  118,    1,
+ /*  1520 */    16,  120,   53,   53,  118,   20,   59,  107,   22,  126,
+ /*  1530 */    23,   16,   23,   22,  127,   15,  140,   65,    3,  253,
+ /*  1540 */     4,
+};
+#define YY_SHIFT_USE_DFLT (-110)
+#define YY_SHIFT_MAX 417
+static const short yy_shift_ofst[] = {
+ /*     0 */   111, 1091, 1198, 1091, 1223, 1223,   -2,   88,   88,  -19,
+ /*    10 */  1223, 1223, 1223, 1223, 1223,  210,  465,  129, 1104, 1223,
+ /*    20 */  1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223,
+ /*    30 */  1223, 1223, 1246, 1223, 1223, 1223, 1223, 1223, 1223, 1223,
+ /*    40 */  1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223,
+ /*    50 */  1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223, 1223,
+ /*    60 */  1223,  -49,  361,  465,  465,  154,  138,  138, -109,   55,
+ /*    70 */   203,  277,  351,  425,  499,  573,  647,  721,  795,  869,
+ /*    80 */   795,  795,  795,  795,  795,  795,  795,  795,  795,  795,
+ /*    90 */   795,  795,  795,  795,  795,  795,  795,  795,  943, 1017,
+ /*   100 */  1017,  -69,  -69,  -69,  -69,   -1,   -1,   57,  155,  -44,
+ /*   110 */   465,  465,  465,  465,  465,  654,  205,  465,  465,  465,
+ /*   120 */   465,  465,  465,  465,  465,  465,  465,  465,  465,  465,
+ /*   130 */   465,  465,  465,  248,  154,  -80, -110, -110, -110, 1303,
+ /*   140 */   131,   95,  291,  352,  458,  510,  582,  582,  465,  465,
+ /*   150 */   465,  465,  465,  465,  465,  465,  465,  465,  465,  465,
+ /*   160 */   465,  465,  465,  465,  465,  465,  465,  465,  465,  465,
+ /*   170 */   465,  465,  465,  465,  465,  465,  465,  465,  465,  465,
+ /*   180 */   613,  683,  601,  379,  379,  379,  657,  586, -109, -109,
+ /*   190 */  -109, -110, -110, -110,  172,  172,  275,  160,  516,  667,
+ /*   200 */   724,  442,  744,  883,   60,   60,  612,  367,  236,  803,
+ /*   210 */   708,  708,  143,  718,  708,  708,  708,  708,  542,  426,
+ /*   220 */   438,  154,  773,  773,  713,  428,  428,  904,  428,  876,
+ /*   230 */   428,  154,  428,  154,  643, 1024,  946, 1024,  904,  904,
+ /*   240 */   946, 1115, 1115, 1115, 1115, 1129, 1129, 1127, -109, 1040,
+ /*   250 */  1052, 1059, 1062, 1072, 1066, 1113, 1113, 1140, 1137, 1140,
+ /*   260 */  1137, 1140, 1137, 1154, 1154, 1231, 1154, 1211, 1154, 1302,
+ /*   270 */  1256, 1256, 1231, 1154, 1154, 1154, 1302, 1378, 1113, 1378,
+ /*   280 */  1113, 1378, 1113, 1113, 1353, 1276, 1378, 1113, 1344, 1344,
+ /*   290 */  1404, 1040, 1113, 1412, 1412, 1412, 1412, 1040, 1344, 1404,
+ /*   300 */  1113, 1397, 1397, 1113, 1113, 1408, -110, -110, -110, -110,
+ /*   310 */  -110, -110,  939,   46,  547,  905,  983,  971,  972,  970,
+ /*   320 */  1037,  941,  982, 1029, 1047, 1097, 1110, 1128, 1262, 1263,
+ /*   330 */  1093, 1297, 1450, 1437, 1431, 1435, 1341, 1343, 1345, 1346,
+ /*   340 */  1347, 1349, 1443, 1444, 1445, 1447, 1455, 1448, 1449, 1446,
+ /*   350 */  1451, 1452, 1453, 1438, 1454, 1441, 1453, 1358, 1458, 1456,
+ /*   360 */  1457, 1364, 1459, 1460, 1461, 1433, 1464, 1463, 1436, 1465,
+ /*   370 */  1466, 1468, 1471, 1442, 1473, 1394, 1389, 1479, 1481, 1475,
+ /*   380 */  1398, 1462, 1467, 1469, 1478, 1470, 1366, 1402, 1485, 1503,
+ /*   390 */  1508, 1393, 1476, 1486, 1405, 1439, 1440, 1388, 1495, 1400,
+ /*   400 */  1518, 1504, 1401, 1505, 1406, 1420, 1403, 1506, 1407, 1507,
+ /*   410 */  1509, 1515, 1472, 1520, 1396, 1511, 1535, 1536,
+};
+#define YY_REDUCE_USE_DFLT (-197)
+#define YY_REDUCE_MAX 311
+static const short yy_reduce_ofst[] = {
+ /*     0 */  -141,   90,   16,  147,  -55,   21,  148,  149,  158,  240,
+ /*    10 */   223,  237,  242,  303,  307,  164,  370,  171,  369,  376,
+ /*    20 */   380,  443,  450,  504,  517,  524,  535,  537,  578,  591,
+ /*    30 */   594,  599,  611,  652,  665,  668,  686,  726,  739,  742,
+ /*    40 */   746,  760,  800,  816,  834,  874,  888,  890,  908,  911,
+ /*    50 */   962,  975,  989,  993, 1030, 1089, 1096, 1102, 1119, 1125,
+ /*    60 */  1131, -196,  954,  740,  396,  169,  -68,  463,  405,  459,
+ /*    70 */   459,  459,  459,  459,  459,  459,  459,  459,  459,  459,
+ /*    80 */   459,  459,  459,  459,  459,  459,  459,  459,  459,  459,
+ /*    90 */   459,  459,  459,  459,  459,  459,  459,  459,  459,  459,
+ /*   100 */   459,  459,  459,  459,  459,  459,  459,  -21,  459,  459,
+ /*   110 */   538,  375,  592,  666,  814,    6,  222,  521,  682,  817,
+ /*   120 */   356,  244,  466,  684,  691,  891,  994, 1023, 1063, 1142,
+ /*   130 */  1169,  759, 1173,  459,  -89,  459,  459,  459,  459,  285,
+ /*   140 */    76,  430,  598,  610,  765,  818,  423,  485,  892,  909,
+ /*   150 */   910,  969, 1006,  818, 1011, 1016, 1067, 1076, 1132, 1177,
+ /*   160 */  1178, 1181, 1186, 1195, 1199, 1200, 1209, 1217, 1218, 1221,
+ /*   170 */  1222, 1234, 1235, 1238, 1241, 1242, 1243, 1244, 1254, 1255,
+ /*   180 */   532,  532,  549,  178,  324,  688,  446,  769,  776,  809,
+ /*   190 */   813,  655,  581,  738,  -74,  -58,  -50,  -17,  -23,  -23,
+ /*   200 */   -23,   63,  -23,   29,   68,  121,  183,  146,  225,   29,
+ /*   210 */   -23,  -23,  196,  177,  -23,  -23,  -23,  -23,  255,  328,
+ /*   220 */   335,  381,  404,  439,  449,  600,  648,  546,  685,  638,
+ /*   230 */   717,  663,  722,  811,  734,  756,  801,  827,  868,  872,
+ /*   240 */   899,  967,  980,  996,  997,  981,  987, 1003,  961,  976,
+ /*   250 */   979,  992,  998, 1004,  991, 1057, 1070, 1009, 1036, 1038,
+ /*   260 */  1069, 1041, 1080, 1098, 1122, 1111, 1135, 1123, 1139, 1168,
+ /*   270 */  1133, 1143, 1174, 1185, 1194, 1205, 1216, 1257, 1245, 1258,
+ /*   280 */  1253, 1259, 1260, 1261, 1183, 1184, 1266, 1267, 1227, 1236,
+ /*   290 */  1208, 1229, 1272, 1239, 1247, 1248, 1249, 1237, 1264, 1219,
+ /*   300 */  1278, 1201, 1202, 1285, 1286, 1203, 1283, 1268, 1270, 1206,
+ /*   310 */  1204, 1207,
+};
+static const YYACTIONTYPE yy_default[] = {
+ /*     0 */   634,  869,  958,  958,  869,  958,  958,  898,  898,  757,
+ /*    10 */   867,  958,  958,  958,  958,  958,  958,  932,  958,  958,
+ /*    20 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*    30 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*    40 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*    50 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*    60 */   958,  841,  958,  958,  958,  673,  898,  898,  761,  792,
+ /*    70 */   958,  958,  958,  958,  958,  958,  958,  958,  793,  958,
+ /*    80 */   871,  866,  862,  864,  863,  870,  794,  783,  790,  797,
+ /*    90 */   772,  911,  799,  800,  806,  807,  933,  931,  829,  828,
+ /*   100 */   847,  831,  845,  853,  846,  830,  840,  665,  832,  833,
+ /*   110 */   958,  958,  958,  958,  958,  726,  660,  958,  958,  958,
+ /*   120 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   130 */   958,  958,  958,  834,  958,  835,  848,  849,  850,  958,
+ /*   140 */   958,  958,  958,  958,  958,  958,  958,  958,  640,  958,
+ /*   150 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   160 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   170 */   958,  958,  958,  958,  958,  882,  958,  936,  938,  958,
+ /*   180 */   958,  958,  634,  757,  757,  757,  958,  958,  958,  958,
+ /*   190 */   958,  751,  761,  950,  958,  958,  717,  958,  958,  958,
+ /*   200 */   958,  958,  958,  958,  958,  958,  642,  749,  675,  759,
+ /*   210 */   662,  738,  904,  958,  923,  921,  740,  802,  958,  749,
+ /*   220 */   758,  958,  958,  958,  865,  786,  786,  774,  786,  696,
+ /*   230 */   786,  958,  786,  958,  699,  916,  796,  916,  774,  774,
+ /*   240 */   796,  639,  639,  639,  639,  650,  650,  716,  958,  796,
+ /*   250 */   787,  789,  779,  791,  958,  765,  765,  773,  778,  773,
+ /*   260 */   778,  773,  778,  728,  728,  713,  728,  699,  728,  875,
+ /*   270 */   879,  879,  713,  728,  728,  728,  875,  657,  765,  657,
+ /*   280 */   765,  657,  765,  765,  908,  910,  657,  765,  730,  730,
+ /*   290 */   808,  796,  765,  737,  737,  737,  737,  796,  730,  808,
+ /*   300 */   765,  935,  935,  765,  765,  943,  683,  701,  701,  950,
+ /*   310 */   955,  955,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   320 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   330 */   884,  958,  958,  648,  958,  667,  815,  820,  816,  958,
+ /*   340 */   817,  743,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   350 */   958,  958,  868,  958,  780,  958,  788,  958,  958,  958,
+ /*   360 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   370 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   380 */   958,  958,  958,  906,  907,  958,  958,  958,  958,  958,
+ /*   390 */   958,  914,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   400 */   958,  958,  958,  958,  958,  958,  958,  958,  958,  958,
+ /*   410 */   958,  958,  942,  958,  958,  945,  635,  958,  630,  632,
+ /*   420 */   633,  637,  638,  641,  667,  668,  670,  671,  672,  643,
+ /*   430 */   644,  645,  646,  647,  649,  653,  651,  652,  654,  661,
+ /*   440 */   663,  682,  684,  686,  747,  748,  812,  741,  742,  746,
+ /*   450 */   669,  823,  814,  818,  819,  821,  822,  836,  837,  839,
+ /*   460 */   844,  852,  855,  838,  843,  851,  854,  744,  745,  858,
+ /*   470 */   676,  677,  680,  681,  894,  896,  895,  897,  679,  678,
+ /*   480 */   824,  827,  860,  861,  924,  925,  926,  927,  928,  856,
+ /*   490 */   766,  859,  842,  781,  784,  785,  782,  750,  760,  768,
+ /*   500 */   769,  770,  771,  755,  756,  762,  777,  810,  811,  775,
+ /*   510 */   776,  763,  764,  752,  753,  754,  857,  813,  825,  826,
+ /*   520 */   687,  688,  820,  689,  690,  691,  729,  732,  733,  734,
+ /*   530 */   692,  711,  714,  715,  693,  700,  694,  695,  702,  703,
+ /*   540 */   704,  706,  707,  708,  709,  710,  705,  876,  877,  880,
+ /*   550 */   878,  697,  698,  712,  685,  674,  666,  718,  721,  722,
+ /*   560 */   723,  724,  725,  727,  719,  720,  664,  655,  658,  767,
+ /*   570 */   900,  909,  905,  901,  902,  903,  659,  872,  873,  731,
+ /*   580 */   804,  805,  899,  912,  915,  917,  918,  919,  809,  920,
+ /*   590 */   922,  913,  947,  656,  735,  736,  739,  881,  929,  795,
+ /*   600 */   798,  801,  803,  883,  885,  887,  889,  890,  891,  892,
+ /*   610 */   893,  886,  888,  930,  934,  937,  939,  940,  941,  944,
+ /*   620 */   946,  951,  952,  953,  956,  957,  954,  636,  631,
+};
+#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
 
-  return rc;
-}
-#endif  /* SQLITE_OMIT_VACUUM && SQLITE_OMIT_ATTACH */
+/* The next table maps tokens into fallback tokens.  If a construct
+** like the following:
+** 
+**      %fallback ID X Y Z.
+**
+** appears in the grammar, then ID becomes a fallback token for X, Y,
+** and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
+** but it does not parse, the type of the token is changed to ID and
+** the parse is retried before an error is thrown.
+*/
+#ifdef YYFALLBACK
+static const YYCODETYPE yyFallback[] = {
+    0,  /*          $ => nothing */
+    0,  /*       SEMI => nothing */
+   26,  /*    EXPLAIN => ID */
+   26,  /*      QUERY => ID */
+   26,  /*       PLAN => ID */
+   26,  /*      BEGIN => ID */
+    0,  /* TRANSACTION => nothing */
+   26,  /*   DEFERRED => ID */
+   26,  /*  IMMEDIATE => ID */
+   26,  /*  EXCLUSIVE => ID */
+    0,  /*     COMMIT => nothing */
+   26,  /*        END => ID */
+   26,  /*   ROLLBACK => ID */
+   26,  /*  SAVEPOINT => ID */
+   26,  /*    RELEASE => ID */
+    0,  /*         TO => nothing */
+    0,  /*      TABLE => nothing */
+    0,  /*     CREATE => nothing */
+   26,  /*         IF => ID */
+    0,  /*        NOT => nothing */
+    0,  /*     EXISTS => nothing */
+   26,  /*       TEMP => ID */
+    0,  /*         LP => nothing */
+    0,  /*         RP => nothing */
+    0,  /*         AS => nothing */
+    0,  /*      COMMA => nothing */
+    0,  /*         ID => nothing */
+    0,  /*    INDEXED => nothing */
+   26,  /*      ABORT => ID */
+   26,  /*     ACTION => ID */
+   26,  /*      AFTER => ID */
+   26,  /*    ANALYZE => ID */
+   26,  /*        ASC => ID */
+   26,  /*     ATTACH => ID */
+   26,  /*     BEFORE => ID */
+   26,  /*         BY => ID */
+   26,  /*    CASCADE => ID */
+   26,  /*       CAST => ID */
+   26,  /*   COLUMNKW => ID */
+   26,  /*   CONFLICT => ID */
+   26,  /*   DATABASE => ID */
+   26,  /*       DESC => ID */
+   26,  /*     DETACH => ID */
+   26,  /*       EACH => ID */
+   26,  /*       FAIL => ID */
+   26,  /*        FOR => ID */
+   26,  /*     IGNORE => ID */
+   26,  /*  INITIALLY => ID */
+   26,  /*    INSTEAD => ID */
+   26,  /*    LIKE_KW => ID */
+   26,  /*      MATCH => ID */
+   26,  /*         NO => ID */
+   26,  /*        KEY => ID */
+   26,  /*         OF => ID */
+   26,  /*     OFFSET => ID */
+   26,  /*     PRAGMA => ID */
+   26,  /*      RAISE => ID */
+   26,  /*    REPLACE => ID */
+   26,  /*   RESTRICT => ID */
+   26,  /*        ROW => ID */
+   26,  /*    TRIGGER => ID */
+   26,  /*     VACUUM => ID */
+   26,  /*       VIEW => ID */
+   26,  /*    VIRTUAL => ID */
+   26,  /*    REINDEX => ID */
+   26,  /*     RENAME => ID */
+   26,  /*   CTIME_KW => ID */
+};
+#endif /* YYFALLBACK */
 
-/************** End of vacuum.c **********************************************/
-/************** Begin file vtab.c ********************************************/
-/*
-** 2006 June 10
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+/* The following structure represents a single element of the
+** parser's stack.  Information stored includes:
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+**   +  The state number for the parser at this level of the stack.
 **
-*************************************************************************
-** This file contains code used to help implement virtual tables.
+**   +  The value of the token stored at this level of the stack.
+**      (In other words, the "major" token.)
 **
-** $Id: vtab.c,v 1.69 2008/05/05 13:23:04 drh Exp $
+**   +  The semantic value stored at this level of the stack.  This is
+**      the information used by the action routines in the grammar.
+**      It is sometimes called the "minor" token.
 */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-
-static int createModule(
-  sqlite3 *db,                    /* Database in which module is registered */
-  const char *zName,              /* Name assigned to this module */
-  const sqlite3_module *pModule,  /* The definition of the module */
-  void *pAux,                     /* Context pointer for xCreate/xConnect */
-  void (*xDestroy)(void *)        /* Module destructor function */
-) {
-  int rc, nName;
-  Module *pMod;
+struct yyStackEntry {
+  YYACTIONTYPE stateno;  /* The state-number */
+  YYCODETYPE major;      /* The major token value.  This is the code
+                         ** number for the token at this stack level */
+  YYMINORTYPE minor;     /* The user-supplied minor token value.  This
+                         ** is the value of the token  */
+};
+typedef struct yyStackEntry yyStackEntry;
 
-  sqlite3_mutex_enter(db->mutex);
-  nName = strlen(zName);
-  pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
-  if( pMod ){
-    char *zCopy = (char *)(&pMod[1]);
-    memcpy(zCopy, zName, nName+1);
-    pMod->zName = zCopy;
-    pMod->pModule = pModule;
-    pMod->pAux = pAux;
-    pMod->xDestroy = xDestroy;
-    pMod = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
-    if( pMod && pMod->xDestroy ){
-      pMod->xDestroy(pMod->pAux);
-    }
-    sqlite3_free(pMod);
-    sqlite3ResetInternalSchema(db, 0);
-  }
-  rc = sqlite3ApiExit(db, SQLITE_OK);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
+/* The state of the parser is completely contained in an instance of
+** the following structure */
+struct yyParser {
+  int yyidx;                    /* Index of top element in stack */
+#ifdef YYTRACKMAXSTACKDEPTH
+  int yyidxMax;                 /* Maximum value of yyidx */
+#endif
+  int yyerrcnt;                 /* Shifts left before out of the error */
+  sqlite3ParserARG_SDECL                /* A place to hold %extra_argument */
+#if YYSTACKDEPTH<=0
+  int yystksz;                  /* Current side of the stack */
+  yyStackEntry *yystack;        /* The parser's stack */
+#else
+  yyStackEntry yystack[YYSTACKDEPTH];  /* The parser's stack */
+#endif
+};
+typedef struct yyParser yyParser;
 
+#ifndef NDEBUG
+static FILE *yyTraceFILE = 0;
+static char *yyTracePrompt = 0;
+#endif /* NDEBUG */
 
-/*
-** External API function used to create a new virtual-table module.
+#ifndef NDEBUG
+/* 
+** Turn parser tracing on by giving a stream to which to write the trace
+** and a prompt to preface each trace message.  Tracing is turned off
+** by making either argument NULL 
+**
+** Inputs:
+** <ul>
+** <li> A FILE* to which trace output should be written.
+**      If NULL, then tracing is turned off.
+** <li> A prefix string written at the beginning of every
+**      line of trace output.  If NULL, then tracing is
+**      turned off.
+** </ul>
+**
+** Outputs:
+** None.
 */
-SQLITE_API int sqlite3_create_module(
-  sqlite3 *db,                    /* Database in which module is registered */
-  const char *zName,              /* Name assigned to this module */
-  const sqlite3_module *pModule,  /* The definition of the module */
-  void *pAux                      /* Context pointer for xCreate/xConnect */
-){
-  return createModule(db, zName, pModule, pAux, 0);
+SQLITE_PRIVATE void sqlite3ParserTrace(FILE *TraceFILE, char *zTracePrompt){
+  yyTraceFILE = TraceFILE;
+  yyTracePrompt = zTracePrompt;
+  if( yyTraceFILE==0 ) yyTracePrompt = 0;
+  else if( yyTracePrompt==0 ) yyTraceFILE = 0;
 }
+#endif /* NDEBUG */
 
-/*
-** External API function used to create a new virtual-table module.
-*/
-SQLITE_API int sqlite3_create_module_v2(
-  sqlite3 *db,                    /* Database in which module is registered */
-  const char *zName,              /* Name assigned to this module */
-  const sqlite3_module *pModule,  /* The definition of the module */
-  void *pAux,                     /* Context pointer for xCreate/xConnect */
-  void (*xDestroy)(void *)        /* Module destructor function */
-){
-  return createModule(db, zName, pModule, pAux, xDestroy);
-}
+#ifndef NDEBUG
+/* For tracing shifts, the names of all terminals and nonterminals
+** are required.  The following table supplies these names */
+static const char *const yyTokenName[] = { 
+  "$",             "SEMI",          "EXPLAIN",       "QUERY",       
+  "PLAN",          "BEGIN",         "TRANSACTION",   "DEFERRED",    
+  "IMMEDIATE",     "EXCLUSIVE",     "COMMIT",        "END",         
+  "ROLLBACK",      "SAVEPOINT",     "RELEASE",       "TO",          
+  "TABLE",         "CREATE",        "IF",            "NOT",         
+  "EXISTS",        "TEMP",          "LP",            "RP",          
+  "AS",            "COMMA",         "ID",            "INDEXED",     
+  "ABORT",         "ACTION",        "AFTER",         "ANALYZE",     
+  "ASC",           "ATTACH",        "BEFORE",        "BY",          
+  "CASCADE",       "CAST",          "COLUMNKW",      "CONFLICT",    
+  "DATABASE",      "DESC",          "DETACH",        "EACH",        
+  "FAIL",          "FOR",           "IGNORE",        "INITIALLY",   
+  "INSTEAD",       "LIKE_KW",       "MATCH",         "NO",          
+  "KEY",           "OF",            "OFFSET",        "PRAGMA",      
+  "RAISE",         "REPLACE",       "RESTRICT",      "ROW",         
+  "TRIGGER",       "VACUUM",        "VIEW",          "VIRTUAL",     
+  "REINDEX",       "RENAME",        "CTIME_KW",      "ANY",         
+  "OR",            "AND",           "IS",            "BETWEEN",     
+  "IN",            "ISNULL",        "NOTNULL",       "NE",          
+  "EQ",            "GT",            "LE",            "LT",          
+  "GE",            "ESCAPE",        "BITAND",        "BITOR",       
+  "LSHIFT",        "RSHIFT",        "PLUS",          "MINUS",       
+  "STAR",          "SLASH",         "REM",           "CONCAT",      
+  "COLLATE",       "BITNOT",        "STRING",        "JOIN_KW",     
+  "CONSTRAINT",    "DEFAULT",       "NULL",          "PRIMARY",     
+  "UNIQUE",        "CHECK",         "REFERENCES",    "AUTOINCR",    
+  "ON",            "DELETE",        "UPDATE",        "SET",         
+  "DEFERRABLE",    "FOREIGN",       "DROP",          "UNION",       
+  "ALL",           "EXCEPT",        "INTERSECT",     "SELECT",      
+  "DISTINCT",      "DOT",           "FROM",          "JOIN",        
+  "USING",         "ORDER",         "GROUP",         "HAVING",      
+  "LIMIT",         "WHERE",         "INTO",          "VALUES",      
+  "INSERT",        "INTEGER",       "FLOAT",         "BLOB",        
+  "REGISTER",      "VARIABLE",      "CASE",          "WHEN",        
+  "THEN",          "ELSE",          "INDEX",         "ALTER",       
+  "ADD",           "error",         "input",         "cmdlist",     
+  "ecmd",          "explain",       "cmdx",          "cmd",         
+  "transtype",     "trans_opt",     "nm",            "savepoint_opt",
+  "create_table",  "create_table_args",  "createkw",      "temp",        
+  "ifnotexists",   "dbnm",          "columnlist",    "conslist_opt",
+  "select",        "column",        "columnid",      "type",        
+  "carglist",      "id",            "ids",           "typetoken",   
+  "typename",      "signed",        "plus_num",      "minus_num",   
+  "carg",          "ccons",         "term",          "expr",        
+  "onconf",        "sortorder",     "autoinc",       "idxlist_opt", 
+  "refargs",       "defer_subclause",  "refarg",        "refact",      
+  "init_deferred_pred_opt",  "conslist",      "tcons",         "idxlist",     
+  "defer_subclause_opt",  "orconf",        "resolvetype",   "raisetype",   
+  "ifexists",      "fullname",      "oneselect",     "multiselect_op",
+  "distinct",      "selcollist",    "from",          "where_opt",   
+  "groupby_opt",   "having_opt",    "orderby_opt",   "limit_opt",   
+  "sclp",          "as",            "seltablist",    "stl_prefix",  
+  "joinop",        "indexed_opt",   "on_opt",        "using_opt",   
+  "joinop2",       "inscollist",    "sortlist",      "sortitem",    
+  "nexprlist",     "setlist",       "insert_cmd",    "inscollist_opt",
+  "itemlist",      "exprlist",      "likeop",        "escape",      
+  "between_op",    "in_op",         "case_operand",  "case_exprlist",
+  "case_else",     "uniqueflag",    "collate",       "nmnum",       
+  "plus_opt",      "number",        "trigger_decl",  "trigger_cmd_list",
+  "trigger_time",  "trigger_event",  "foreach_clause",  "when_clause", 
+  "trigger_cmd",   "trnm",          "tridxby",       "database_kw_opt",
+  "key_opt",       "add_column_fullname",  "kwcolumn_opt",  "create_vtab", 
+  "vtabarglist",   "vtabarg",       "vtabargtoken",  "lp",          
+  "anylist",     
+};
+#endif /* NDEBUG */
 
-/*
-** Lock the virtual table so that it cannot be disconnected.
-** Locks nest.  Every lock should have a corresponding unlock.
-** If an unlock is omitted, resources leaks will occur.  
-**
-** If a disconnect is attempted while a virtual table is locked,
-** the disconnect is deferred until all locks have been removed.
+#ifndef NDEBUG
+/* For tracing reduce actions, the names of all rules are required.
 */
-SQLITE_PRIVATE void sqlite3VtabLock(sqlite3_vtab *pVtab){
-  pVtab->nRef++;
-}
+static const char *const yyRuleName[] = {
+ /*   0 */ "input ::= cmdlist",
+ /*   1 */ "cmdlist ::= cmdlist ecmd",
+ /*   2 */ "cmdlist ::= ecmd",
+ /*   3 */ "ecmd ::= SEMI",
+ /*   4 */ "ecmd ::= explain cmdx SEMI",
+ /*   5 */ "explain ::=",
+ /*   6 */ "explain ::= EXPLAIN",
+ /*   7 */ "explain ::= EXPLAIN QUERY PLAN",
+ /*   8 */ "cmdx ::= cmd",
+ /*   9 */ "cmd ::= BEGIN transtype trans_opt",
+ /*  10 */ "trans_opt ::=",
+ /*  11 */ "trans_opt ::= TRANSACTION",
+ /*  12 */ "trans_opt ::= TRANSACTION nm",
+ /*  13 */ "transtype ::=",
+ /*  14 */ "transtype ::= DEFERRED",
+ /*  15 */ "transtype ::= IMMEDIATE",
+ /*  16 */ "transtype ::= EXCLUSIVE",
+ /*  17 */ "cmd ::= COMMIT trans_opt",
+ /*  18 */ "cmd ::= END trans_opt",
+ /*  19 */ "cmd ::= ROLLBACK trans_opt",
+ /*  20 */ "savepoint_opt ::= SAVEPOINT",
+ /*  21 */ "savepoint_opt ::=",
+ /*  22 */ "cmd ::= SAVEPOINT nm",
+ /*  23 */ "cmd ::= RELEASE savepoint_opt nm",
+ /*  24 */ "cmd ::= ROLLBACK trans_opt TO savepoint_opt nm",
+ /*  25 */ "cmd ::= create_table create_table_args",
+ /*  26 */ "create_table ::= createkw temp TABLE ifnotexists nm dbnm",
+ /*  27 */ "createkw ::= CREATE",
+ /*  28 */ "ifnotexists ::=",
+ /*  29 */ "ifnotexists ::= IF NOT EXISTS",
+ /*  30 */ "temp ::= TEMP",
+ /*  31 */ "temp ::=",
+ /*  32 */ "create_table_args ::= LP columnlist conslist_opt RP",
+ /*  33 */ "create_table_args ::= AS select",
+ /*  34 */ "columnlist ::= columnlist COMMA column",
+ /*  35 */ "columnlist ::= column",
+ /*  36 */ "column ::= columnid type carglist",
+ /*  37 */ "columnid ::= nm",
+ /*  38 */ "id ::= ID",
+ /*  39 */ "id ::= INDEXED",
+ /*  40 */ "ids ::= ID|STRING",
+ /*  41 */ "nm ::= id",
+ /*  42 */ "nm ::= STRING",
+ /*  43 */ "nm ::= JOIN_KW",
+ /*  44 */ "type ::=",
+ /*  45 */ "type ::= typetoken",
+ /*  46 */ "typetoken ::= typename",
+ /*  47 */ "typetoken ::= typename LP signed RP",
+ /*  48 */ "typetoken ::= typename LP signed COMMA signed RP",
+ /*  49 */ "typename ::= ids",
+ /*  50 */ "typename ::= typename ids",
+ /*  51 */ "signed ::= plus_num",
+ /*  52 */ "signed ::= minus_num",
+ /*  53 */ "carglist ::= carglist carg",
+ /*  54 */ "carglist ::=",
+ /*  55 */ "carg ::= CONSTRAINT nm ccons",
+ /*  56 */ "carg ::= ccons",
+ /*  57 */ "ccons ::= DEFAULT term",
+ /*  58 */ "ccons ::= DEFAULT LP expr RP",
+ /*  59 */ "ccons ::= DEFAULT PLUS term",
+ /*  60 */ "ccons ::= DEFAULT MINUS term",
+ /*  61 */ "ccons ::= DEFAULT id",
+ /*  62 */ "ccons ::= NULL onconf",
+ /*  63 */ "ccons ::= NOT NULL onconf",
+ /*  64 */ "ccons ::= PRIMARY KEY sortorder onconf autoinc",
+ /*  65 */ "ccons ::= UNIQUE onconf",
+ /*  66 */ "ccons ::= CHECK LP expr RP",
+ /*  67 */ "ccons ::= REFERENCES nm idxlist_opt refargs",
+ /*  68 */ "ccons ::= defer_subclause",
+ /*  69 */ "ccons ::= COLLATE ids",
+ /*  70 */ "autoinc ::=",
+ /*  71 */ "autoinc ::= AUTOINCR",
+ /*  72 */ "refargs ::=",
+ /*  73 */ "refargs ::= refargs refarg",
+ /*  74 */ "refarg ::= MATCH nm",
+ /*  75 */ "refarg ::= ON DELETE refact",
+ /*  76 */ "refarg ::= ON UPDATE refact",
+ /*  77 */ "refact ::= SET NULL",
+ /*  78 */ "refact ::= SET DEFAULT",
+ /*  79 */ "refact ::= CASCADE",
+ /*  80 */ "refact ::= RESTRICT",
+ /*  81 */ "refact ::= NO ACTION",
+ /*  82 */ "defer_subclause ::= NOT DEFERRABLE init_deferred_pred_opt",
+ /*  83 */ "defer_subclause ::= DEFERRABLE init_deferred_pred_opt",
+ /*  84 */ "init_deferred_pred_opt ::=",
+ /*  85 */ "init_deferred_pred_opt ::= INITIALLY DEFERRED",
+ /*  86 */ "init_deferred_pred_opt ::= INITIALLY IMMEDIATE",
+ /*  87 */ "conslist_opt ::=",
+ /*  88 */ "conslist_opt ::= COMMA conslist",
+ /*  89 */ "conslist ::= conslist COMMA tcons",
+ /*  90 */ "conslist ::= conslist tcons",
+ /*  91 */ "conslist ::= tcons",
+ /*  92 */ "tcons ::= CONSTRAINT nm",
+ /*  93 */ "tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf",
+ /*  94 */ "tcons ::= UNIQUE LP idxlist RP onconf",
+ /*  95 */ "tcons ::= CHECK LP expr RP onconf",
+ /*  96 */ "tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt",
+ /*  97 */ "defer_subclause_opt ::=",
+ /*  98 */ "defer_subclause_opt ::= defer_subclause",
+ /*  99 */ "onconf ::=",
+ /* 100 */ "onconf ::= ON CONFLICT resolvetype",
+ /* 101 */ "orconf ::=",
+ /* 102 */ "orconf ::= OR resolvetype",
+ /* 103 */ "resolvetype ::= raisetype",
+ /* 104 */ "resolvetype ::= IGNORE",
+ /* 105 */ "resolvetype ::= REPLACE",
+ /* 106 */ "cmd ::= DROP TABLE ifexists fullname",
+ /* 107 */ "ifexists ::= IF EXISTS",
+ /* 108 */ "ifexists ::=",
+ /* 109 */ "cmd ::= createkw temp VIEW ifnotexists nm dbnm AS select",
+ /* 110 */ "cmd ::= DROP VIEW ifexists fullname",
+ /* 111 */ "cmd ::= select",
+ /* 112 */ "select ::= oneselect",
+ /* 113 */ "select ::= select multiselect_op oneselect",
+ /* 114 */ "multiselect_op ::= UNION",
+ /* 115 */ "multiselect_op ::= UNION ALL",
+ /* 116 */ "multiselect_op ::= EXCEPT|INTERSECT",
+ /* 117 */ "oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt",
+ /* 118 */ "distinct ::= DISTINCT",
+ /* 119 */ "distinct ::= ALL",
+ /* 120 */ "distinct ::=",
+ /* 121 */ "sclp ::= selcollist COMMA",
+ /* 122 */ "sclp ::=",
+ /* 123 */ "selcollist ::= sclp expr as",
+ /* 124 */ "selcollist ::= sclp STAR",
+ /* 125 */ "selcollist ::= sclp nm DOT STAR",
+ /* 126 */ "as ::= AS nm",
+ /* 127 */ "as ::= ids",
+ /* 128 */ "as ::=",
+ /* 129 */ "from ::=",
+ /* 130 */ "from ::= FROM seltablist",
+ /* 131 */ "stl_prefix ::= seltablist joinop",
+ /* 132 */ "stl_prefix ::=",
+ /* 133 */ "seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt",
+ /* 134 */ "seltablist ::= stl_prefix LP select RP as on_opt using_opt",
+ /* 135 */ "seltablist ::= stl_prefix LP seltablist RP as on_opt using_opt",
+ /* 136 */ "dbnm ::=",
+ /* 137 */ "dbnm ::= DOT nm",
+ /* 138 */ "fullname ::= nm dbnm",
+ /* 139 */ "joinop ::= COMMA|JOIN",
+ /* 140 */ "joinop ::= JOIN_KW JOIN",
+ /* 141 */ "joinop ::= JOIN_KW nm JOIN",
+ /* 142 */ "joinop ::= JOIN_KW nm nm JOIN",
+ /* 143 */ "on_opt ::= ON expr",
+ /* 144 */ "on_opt ::=",
+ /* 145 */ "indexed_opt ::=",
+ /* 146 */ "indexed_opt ::= INDEXED BY nm",
+ /* 147 */ "indexed_opt ::= NOT INDEXED",
+ /* 148 */ "using_opt ::= USING LP inscollist RP",
+ /* 149 */ "using_opt ::=",
+ /* 150 */ "orderby_opt ::=",
+ /* 151 */ "orderby_opt ::= ORDER BY sortlist",
+ /* 152 */ "sortlist ::= sortlist COMMA sortitem sortorder",
+ /* 153 */ "sortlist ::= sortitem sortorder",
+ /* 154 */ "sortitem ::= expr",
+ /* 155 */ "sortorder ::= ASC",
+ /* 156 */ "sortorder ::= DESC",
+ /* 157 */ "sortorder ::=",
+ /* 158 */ "groupby_opt ::=",
+ /* 159 */ "groupby_opt ::= GROUP BY nexprlist",
+ /* 160 */ "having_opt ::=",
+ /* 161 */ "having_opt ::= HAVING expr",
+ /* 162 */ "limit_opt ::=",
+ /* 163 */ "limit_opt ::= LIMIT expr",
+ /* 164 */ "limit_opt ::= LIMIT expr OFFSET expr",
+ /* 165 */ "limit_opt ::= LIMIT expr COMMA expr",
+ /* 166 */ "cmd ::= DELETE FROM fullname indexed_opt where_opt",
+ /* 167 */ "where_opt ::=",
+ /* 168 */ "where_opt ::= WHERE expr",
+ /* 169 */ "cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt",
+ /* 170 */ "setlist ::= setlist COMMA nm EQ expr",
+ /* 171 */ "setlist ::= nm EQ expr",
+ /* 172 */ "cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP",
+ /* 173 */ "cmd ::= insert_cmd INTO fullname inscollist_opt select",
+ /* 174 */ "cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES",
+ /* 175 */ "insert_cmd ::= INSERT orconf",
+ /* 176 */ "insert_cmd ::= REPLACE",
+ /* 177 */ "itemlist ::= itemlist COMMA expr",
+ /* 178 */ "itemlist ::= expr",
+ /* 179 */ "inscollist_opt ::=",
+ /* 180 */ "inscollist_opt ::= LP inscollist RP",
+ /* 181 */ "inscollist ::= inscollist COMMA nm",
+ /* 182 */ "inscollist ::= nm",
+ /* 183 */ "expr ::= term",
+ /* 184 */ "expr ::= LP expr RP",
+ /* 185 */ "term ::= NULL",
+ /* 186 */ "expr ::= id",
+ /* 187 */ "expr ::= JOIN_KW",
+ /* 188 */ "expr ::= nm DOT nm",
+ /* 189 */ "expr ::= nm DOT nm DOT nm",
+ /* 190 */ "term ::= INTEGER|FLOAT|BLOB",
+ /* 191 */ "term ::= STRING",
+ /* 192 */ "expr ::= REGISTER",
+ /* 193 */ "expr ::= VARIABLE",
+ /* 194 */ "expr ::= expr COLLATE ids",
+ /* 195 */ "expr ::= CAST LP expr AS typetoken RP",
+ /* 196 */ "expr ::= ID LP distinct exprlist RP",
+ /* 197 */ "expr ::= ID LP STAR RP",
+ /* 198 */ "term ::= CTIME_KW",
+ /* 199 */ "expr ::= expr AND expr",
+ /* 200 */ "expr ::= expr OR expr",
+ /* 201 */ "expr ::= expr LT|GT|GE|LE expr",
+ /* 202 */ "expr ::= expr EQ|NE expr",
+ /* 203 */ "expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr",
+ /* 204 */ "expr ::= expr PLUS|MINUS expr",
+ /* 205 */ "expr ::= expr STAR|SLASH|REM expr",
+ /* 206 */ "expr ::= expr CONCAT expr",
+ /* 207 */ "likeop ::= LIKE_KW",
+ /* 208 */ "likeop ::= NOT LIKE_KW",
+ /* 209 */ "likeop ::= MATCH",
+ /* 210 */ "likeop ::= NOT MATCH",
+ /* 211 */ "escape ::= ESCAPE expr",
+ /* 212 */ "escape ::=",
+ /* 213 */ "expr ::= expr likeop expr escape",
+ /* 214 */ "expr ::= expr ISNULL|NOTNULL",
+ /* 215 */ "expr ::= expr NOT NULL",
+ /* 216 */ "expr ::= expr IS expr",
+ /* 217 */ "expr ::= expr IS NOT expr",
+ /* 218 */ "expr ::= NOT expr",
+ /* 219 */ "expr ::= BITNOT expr",
+ /* 220 */ "expr ::= MINUS expr",
+ /* 221 */ "expr ::= PLUS expr",
+ /* 222 */ "between_op ::= BETWEEN",
+ /* 223 */ "between_op ::= NOT BETWEEN",
+ /* 224 */ "expr ::= expr between_op expr AND expr",
+ /* 225 */ "in_op ::= IN",
+ /* 226 */ "in_op ::= NOT IN",
+ /* 227 */ "expr ::= expr in_op LP exprlist RP",
+ /* 228 */ "expr ::= LP select RP",
+ /* 229 */ "expr ::= expr in_op LP select RP",
+ /* 230 */ "expr ::= expr in_op nm dbnm",
+ /* 231 */ "expr ::= EXISTS LP select RP",
+ /* 232 */ "expr ::= CASE case_operand case_exprlist case_else END",
+ /* 233 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
+ /* 234 */ "case_exprlist ::= WHEN expr THEN expr",
+ /* 235 */ "case_else ::= ELSE expr",
+ /* 236 */ "case_else ::=",
+ /* 237 */ "case_operand ::= expr",
+ /* 238 */ "case_operand ::=",
+ /* 239 */ "exprlist ::= nexprlist",
+ /* 240 */ "exprlist ::=",
+ /* 241 */ "nexprlist ::= nexprlist COMMA expr",
+ /* 242 */ "nexprlist ::= expr",
+ /* 243 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
+ /* 244 */ "uniqueflag ::= UNIQUE",
+ /* 245 */ "uniqueflag ::=",
+ /* 246 */ "idxlist_opt ::=",
+ /* 247 */ "idxlist_opt ::= LP idxlist RP",
+ /* 248 */ "idxlist ::= idxlist COMMA nm collate sortorder",
+ /* 249 */ "idxlist ::= nm collate sortorder",
+ /* 250 */ "collate ::=",
+ /* 251 */ "collate ::= COLLATE ids",
+ /* 252 */ "cmd ::= DROP INDEX ifexists fullname",
+ /* 253 */ "cmd ::= VACUUM",
+ /* 254 */ "cmd ::= VACUUM nm",
+ /* 255 */ "cmd ::= PRAGMA nm dbnm",
+ /* 256 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
+ /* 257 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
+ /* 258 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
+ /* 259 */ "cmd ::= PRAGMA nm dbnm LP minus_num RP",
+ /* 260 */ "nmnum ::= plus_num",
+ /* 261 */ "nmnum ::= nm",
+ /* 262 */ "nmnum ::= ON",
+ /* 263 */ "nmnum ::= DELETE",
+ /* 264 */ "nmnum ::= DEFAULT",
+ /* 265 */ "plus_num ::= plus_opt number",
+ /* 266 */ "minus_num ::= MINUS number",
+ /* 267 */ "number ::= INTEGER|FLOAT",
+ /* 268 */ "plus_opt ::= PLUS",
+ /* 269 */ "plus_opt ::=",
+ /* 270 */ "cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END",
+ /* 271 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
+ /* 272 */ "trigger_time ::= BEFORE",
+ /* 273 */ "trigger_time ::= AFTER",
+ /* 274 */ "trigger_time ::= INSTEAD OF",
+ /* 275 */ "trigger_time ::=",
+ /* 276 */ "trigger_event ::= DELETE|INSERT",
+ /* 277 */ "trigger_event ::= UPDATE",
+ /* 278 */ "trigger_event ::= UPDATE OF inscollist",
+ /* 279 */ "foreach_clause ::=",
+ /* 280 */ "foreach_clause ::= FOR EACH ROW",
+ /* 281 */ "when_clause ::=",
+ /* 282 */ "when_clause ::= WHEN expr",
+ /* 283 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
+ /* 284 */ "trigger_cmd_list ::= trigger_cmd SEMI",
+ /* 285 */ "trnm ::= nm",
+ /* 286 */ "trnm ::= nm DOT nm",
+ /* 287 */ "tridxby ::=",
+ /* 288 */ "tridxby ::= INDEXED BY nm",
+ /* 289 */ "tridxby ::= NOT INDEXED",
+ /* 290 */ "trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt",
+ /* 291 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP",
+ /* 292 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select",
+ /* 293 */ "trigger_cmd ::= DELETE FROM trnm tridxby where_opt",
+ /* 294 */ "trigger_cmd ::= select",
+ /* 295 */ "expr ::= RAISE LP IGNORE RP",
+ /* 296 */ "expr ::= RAISE LP raisetype COMMA nm RP",
+ /* 297 */ "raisetype ::= ROLLBACK",
+ /* 298 */ "raisetype ::= ABORT",
+ /* 299 */ "raisetype ::= FAIL",
+ /* 300 */ "cmd ::= DROP TRIGGER ifexists fullname",
+ /* 301 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
+ /* 302 */ "cmd ::= DETACH database_kw_opt expr",
+ /* 303 */ "key_opt ::=",
+ /* 304 */ "key_opt ::= KEY expr",
+ /* 305 */ "database_kw_opt ::= DATABASE",
+ /* 306 */ "database_kw_opt ::=",
+ /* 307 */ "cmd ::= REINDEX",
+ /* 308 */ "cmd ::= REINDEX nm dbnm",
+ /* 309 */ "cmd ::= ANALYZE",
+ /* 310 */ "cmd ::= ANALYZE nm dbnm",
+ /* 311 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
+ /* 312 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
+ /* 313 */ "add_column_fullname ::= fullname",
+ /* 314 */ "kwcolumn_opt ::=",
+ /* 315 */ "kwcolumn_opt ::= COLUMNKW",
+ /* 316 */ "cmd ::= create_vtab",
+ /* 317 */ "cmd ::= create_vtab LP vtabarglist RP",
+ /* 318 */ "create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm",
+ /* 319 */ "vtabarglist ::= vtabarg",
+ /* 320 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
+ /* 321 */ "vtabarg ::=",
+ /* 322 */ "vtabarg ::= vtabarg vtabargtoken",
+ /* 323 */ "vtabargtoken ::= ANY",
+ /* 324 */ "vtabargtoken ::= lp anylist RP",
+ /* 325 */ "lp ::= LP",
+ /* 326 */ "anylist ::=",
+ /* 327 */ "anylist ::= anylist LP anylist RP",
+ /* 328 */ "anylist ::= anylist ANY",
+};
+#endif /* NDEBUG */
 
-/*
-** Unlock a virtual table.  When the last lock is removed,
-** disconnect the virtual table.
-*/
-SQLITE_PRIVATE void sqlite3VtabUnlock(sqlite3 *db, sqlite3_vtab *pVtab){
-  pVtab->nRef--;
-  assert(db);
-  assert( sqlite3SafetyCheckOk(db) );
-  if( pVtab->nRef==0 ){
-    if( db->magic==SQLITE_MAGIC_BUSY ){
-      (void)sqlite3SafetyOff(db);
-      pVtab->pModule->xDisconnect(pVtab);
-      (void)sqlite3SafetyOn(db);
-    } else {
-      pVtab->pModule->xDisconnect(pVtab);
-    }
-  }
-}
 
+#if YYSTACKDEPTH<=0
 /*
-** Clear any and all virtual-table information from the Table record.
-** This routine is called, for example, just before deleting the Table
-** record.
+** Try to increase the size of the parser stack.
 */
-SQLITE_PRIVATE void sqlite3VtabClear(Table *p){
-  sqlite3_vtab *pVtab = p->pVtab;
-  if( pVtab ){
-    assert( p->pMod && p->pMod->pModule );
-    sqlite3VtabUnlock(p->pSchema->db, pVtab);
-    p->pVtab = 0;
-  }
-  if( p->azModuleArg ){
-    int i;
-    for(i=0; i<p->nModuleArg; i++){
-      sqlite3_free(p->azModuleArg[i]);
+static void yyGrowStack(yyParser *p){
+  int newSize;
+  yyStackEntry *pNew;
+
+  newSize = p->yystksz*2 + 100;
+  pNew = realloc(p->yystack, newSize*sizeof(pNew[0]));
+  if( pNew ){
+    p->yystack = pNew;
+    p->yystksz = newSize;
+#ifndef NDEBUG
+    if( yyTraceFILE ){
+      fprintf(yyTraceFILE,"%sStack grows to %d entries!\n",
+              yyTracePrompt, p->yystksz);
     }
-    sqlite3_free(p->azModuleArg);
+#endif
   }
 }
+#endif
 
-/*
-** Add a new module argument to pTable->azModuleArg[].
-** The string is not copied - the pointer is stored.  The
-** string will be freed automatically when the table is
-** deleted.
+/* 
+** This function allocates a new parser.
+** The only argument is a pointer to a function which works like
+** malloc.
+**
+** Inputs:
+** A pointer to the function used to allocate memory.
+**
+** Outputs:
+** A pointer to a parser.  This pointer is used in subsequent calls
+** to sqlite3Parser and sqlite3ParserFree.
 */
-static void addModuleArgument(sqlite3 *db, Table *pTable, char *zArg){
-  int i = pTable->nModuleArg++;
-  int nBytes = sizeof(char *)*(1+pTable->nModuleArg);
-  char **azModuleArg;
-  azModuleArg = sqlite3DbRealloc(db, pTable->azModuleArg, nBytes);
-  if( azModuleArg==0 ){
-    int j;
-    for(j=0; j<i; j++){
-      sqlite3_free(pTable->azModuleArg[j]);
-    }
-    sqlite3_free(zArg);
-    sqlite3_free(pTable->azModuleArg);
-    pTable->nModuleArg = 0;
-  }else{
-    azModuleArg[i] = zArg;
-    azModuleArg[i+1] = 0;
+SQLITE_PRIVATE void *sqlite3ParserAlloc(void *(*mallocProc)(size_t)){
+  yyParser *pParser;
+  pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) );
+  if( pParser ){
+    pParser->yyidx = -1;
+#ifdef YYTRACKMAXSTACKDEPTH
+    pParser->yyidxMax = 0;
+#endif
+#if YYSTACKDEPTH<=0
+    pParser->yystack = NULL;
+    pParser->yystksz = 0;
+    yyGrowStack(pParser);
+#endif
   }
-  pTable->azModuleArg = azModuleArg;
+  return pParser;
 }
 
-/*
-** The parser calls this routine when it first sees a CREATE VIRTUAL TABLE
-** statement.  The module name has been parsed, but the optional list
-** of parameters that follow the module name are still pending.
+/* The following function deletes the value associated with a
+** symbol.  The symbol can be either a terminal or nonterminal.
+** "yymajor" is the symbol code, and "yypminor" is a pointer to
+** the value.
 */
-SQLITE_PRIVATE void sqlite3VtabBeginParse(
-  Parse *pParse,        /* Parsing context */
-  Token *pName1,        /* Name of new table, or database name */
-  Token *pName2,        /* Name of new table or NULL */
-  Token *pModuleName    /* Name of the module for the virtual table */
+static void yy_destructor(
+  yyParser *yypParser,    /* The parser */
+  YYCODETYPE yymajor,     /* Type code for object to destroy */
+  YYMINORTYPE *yypminor   /* The object to be destroyed */
 ){
-  int iDb;              /* The database the table is being created in */
-  Table *pTable;        /* The new virtual table */
-  sqlite3 *db;          /* Database connection */
-
-  if( pParse->db->flags & SQLITE_SharedCache ){
-    sqlite3ErrorMsg(pParse, "Cannot use virtual tables in shared-cache mode");
-    return;
-  }
-
-  sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, 0);
-  pTable = pParse->pNewTable;
-  if( pTable==0 || pParse->nErr ) return;
-  assert( 0==pTable->pIndex );
-
-  db = pParse->db;
-  iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
-  assert( iDb>=0 );
-
-  pTable->isVirtual = 1;
-  pTable->nModuleArg = 0;
-  addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
-  addModuleArgument(db, pTable, sqlite3DbStrDup(db, db->aDb[iDb].zName));
-  addModuleArgument(db, pTable, sqlite3DbStrDup(db, pTable->zName));
-  pParse->sNameToken.n = pModuleName->z + pModuleName->n - pName1->z;
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  /* Creating a virtual table invokes the authorization callback twice.
-  ** The first invocation, to obtain permission to INSERT a row into the
-  ** sqlite_master table, has already been made by sqlite3StartTable().
-  ** The second call, to obtain permission to create the table, is made now.
-  */
-  if( pTable->azModuleArg ){
-    sqlite3AuthCheck(pParse, SQLITE_CREATE_VTABLE, pTable->zName, 
-            pTable->azModuleArg[0], pParse->db->aDb[iDb].zName);
-  }
-#endif
+  sqlite3ParserARG_FETCH;
+  switch( yymajor ){
+    /* Here is inserted the actions which take place when a
+    ** terminal or non-terminal is destroyed.  This can happen
+    ** when the symbol is popped from the stack during a
+    ** reduce or during error processing or when a parser is 
+    ** being destroyed before it is finished parsing.
+    **
+    ** Note: during a reduce, the only symbols destroyed are those
+    ** which appear on the RHS of the rule, but which are not used
+    ** inside the C code.
+    */
+    case 160: /* select */
+    case 194: /* oneselect */
+{
+sqlite3SelectDelete(pParse->db, (yypminor->yy3));
 }
-
-/*
-** This routine takes the module argument that has been accumulating
-** in pParse->zArg[] and appends it to the list of arguments on the
-** virtual table currently under construction in pParse->pTable.
-*/
-static void addArgumentToVtab(Parse *pParse){
-  if( pParse->sArg.z && pParse->pNewTable ){
-    const char *z = (const char*)pParse->sArg.z;
-    int n = pParse->sArg.n;
-    sqlite3 *db = pParse->db;
-    addModuleArgument(db, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
+      break;
+    case 174: /* term */
+    case 175: /* expr */
+    case 223: /* escape */
+{
+sqlite3ExprDelete(pParse->db, (yypminor->yy346).pExpr);
+}
+      break;
+    case 179: /* idxlist_opt */
+    case 187: /* idxlist */
+    case 197: /* selcollist */
+    case 200: /* groupby_opt */
+    case 202: /* orderby_opt */
+    case 204: /* sclp */
+    case 214: /* sortlist */
+    case 216: /* nexprlist */
+    case 217: /* setlist */
+    case 220: /* itemlist */
+    case 221: /* exprlist */
+    case 227: /* case_exprlist */
+{
+sqlite3ExprListDelete(pParse->db, (yypminor->yy14));
+}
+      break;
+    case 193: /* fullname */
+    case 198: /* from */
+    case 206: /* seltablist */
+    case 207: /* stl_prefix */
+{
+sqlite3SrcListDelete(pParse->db, (yypminor->yy65));
+}
+      break;
+    case 199: /* where_opt */
+    case 201: /* having_opt */
+    case 210: /* on_opt */
+    case 215: /* sortitem */
+    case 226: /* case_operand */
+    case 228: /* case_else */
+    case 239: /* when_clause */
+    case 244: /* key_opt */
+{
+sqlite3ExprDelete(pParse->db, (yypminor->yy132));
+}
+      break;
+    case 211: /* using_opt */
+    case 213: /* inscollist */
+    case 219: /* inscollist_opt */
+{
+sqlite3IdListDelete(pParse->db, (yypminor->yy408));
+}
+      break;
+    case 235: /* trigger_cmd_list */
+    case 240: /* trigger_cmd */
+{
+sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy473));
+}
+      break;
+    case 237: /* trigger_event */
+{
+sqlite3IdListDelete(pParse->db, (yypminor->yy378).b);
+}
+      break;
+    default:  break;   /* If no destructor action specified: do nothing */
   }
 }
 
 /*
-** The parser calls this routine after the CREATE VIRTUAL TABLE statement
-** has been completely parsed.
+** Pop the parser's stack once.
+**
+** If there is a destructor routine associated with the token which
+** is popped from the stack, then call it.
+**
+** Return the major token number for the symbol popped.
 */
-SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
-  Table *pTab;        /* The table being constructed */
-  sqlite3 *db;        /* The database connection */
-  char *zModule;      /* The module name of the table: USING modulename */
-  Module *pMod = 0;
-
-  addArgumentToVtab(pParse);
-  pParse->sArg.z = 0;
-
-  /* Lookup the module name. */
-  pTab = pParse->pNewTable;
-  if( pTab==0 ) return;
-  db = pParse->db;
-  if( pTab->nModuleArg<1 ) return;
-  zModule = pTab->azModuleArg[0];
-  pMod = (Module *)sqlite3HashFind(&db->aModule, zModule, strlen(zModule));
-  pTab->pMod = pMod;
-  
-  /* If the CREATE VIRTUAL TABLE statement is being entered for the
-  ** first time (in other words if the virtual table is actually being
-  ** created now instead of just being read out of sqlite_master) then
-  ** do additional initialization work and store the statement text
-  ** in the sqlite_master table.
-  */
-  if( !db->init.busy ){
-    char *zStmt;
-    char *zWhere;
-    int iDb;
-    Vdbe *v;
-
-    /* Compute the complete text of the CREATE VIRTUAL TABLE statement */
-    if( pEnd ){
-      pParse->sNameToken.n = pEnd->z - pParse->sNameToken.z + pEnd->n;
-    }
-    zStmt = sqlite3MPrintf(db, "CREATE VIRTUAL TABLE %T", &pParse->sNameToken);
-
-    /* A slot for the record has already been allocated in the 
-    ** SQLITE_MASTER table.  We just need to update that slot with all
-    ** the information we've collected.  
-    **
-    ** The VM register number pParse->regRowid holds the rowid of an
-    ** entry in the sqlite_master table tht was created for this vtab
-    ** by sqlite3StartTable().
-    */
-    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-    sqlite3NestedParse(pParse,
-      "UPDATE %Q.%s "
-         "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
-       "WHERE rowid=#%d",
-      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
-      pTab->zName,
-      pTab->zName,
-      zStmt,
-      pParse->regRowid
-    );
-    sqlite3_free(zStmt);
-    v = sqlite3GetVdbe(pParse);
-    sqlite3ChangeCookie(pParse, iDb);
-
-    sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
-    zWhere = sqlite3MPrintf(db, "name='%q'", pTab->zName);
-    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 1, 0, zWhere, P4_DYNAMIC);
-    sqlite3VdbeAddOp4(v, OP_VCreate, iDb, 0, 0, 
-                         pTab->zName, strlen(pTab->zName) + 1);
-  }
+static int yy_pop_parser_stack(yyParser *pParser){
+  YYCODETYPE yymajor;
+  yyStackEntry *yytos = &pParser->yystack[pParser->yyidx];
 
-  /* If we are rereading the sqlite_master table create the in-memory
-  ** record of the table. If the module has already been registered,
-  ** also call the xConnect method here.
-  */
-  else {
-    Table *pOld;
-    Schema *pSchema = pTab->pSchema;
-    const char *zName = pTab->zName;
-    int nName = strlen(zName) + 1;
-    pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
-    if( pOld ){
-      db->mallocFailed = 1;
-      assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
-      return;
-    }
-    pSchema->db = pParse->db;
-    pParse->pNewTable = 0;
+  /* There is no mechanism by which the parser stack can be popped below
+  ** empty in SQLite.  */
+  if( NEVER(pParser->yyidx<0) ) return 0;
+#ifndef NDEBUG
+  if( yyTraceFILE && pParser->yyidx>=0 ){
+    fprintf(yyTraceFILE,"%sPopping %s\n",
+      yyTracePrompt,
+      yyTokenName[yytos->major]);
   }
+#endif
+  yymajor = yytos->major;
+  yy_destructor(pParser, yymajor, &yytos->minor);
+  pParser->yyidx--;
+  return yymajor;
 }
 
-/*
-** The parser calls this routine when it sees the first token
-** of an argument to the module name in a CREATE VIRTUAL TABLE statement.
+/* 
+** Deallocate and destroy a parser.  Destructors are all called for
+** all stack elements before shutting the parser down.
+**
+** Inputs:
+** <ul>
+** <li>  A pointer to the parser.  This should be a pointer
+**       obtained from sqlite3ParserAlloc.
+** <li>  A pointer to a function used to reclaim memory obtained
+**       from malloc.
+** </ul>
 */
-SQLITE_PRIVATE void sqlite3VtabArgInit(Parse *pParse){
-  addArgumentToVtab(pParse);
-  pParse->sArg.z = 0;
-  pParse->sArg.n = 0;
+SQLITE_PRIVATE void sqlite3ParserFree(
+  void *p,                    /* The parser to be deleted */
+  void (*freeProc)(void*)     /* Function used to reclaim memory */
+){
+  yyParser *pParser = (yyParser*)p;
+  /* In SQLite, we never try to destroy a parser that was not successfully
+  ** created in the first place. */
+  if( NEVER(pParser==0) ) return;
+  while( pParser->yyidx>=0 ) yy_pop_parser_stack(pParser);
+#if YYSTACKDEPTH<=0
+  free(pParser->yystack);
+#endif
+  (*freeProc)((void*)pParser);
 }
 
 /*
-** The parser calls this routine for each token after the first token
-** in an argument to the module name in a CREATE VIRTUAL TABLE statement.
+** Return the peak depth of the stack for a parser.
 */
-SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse *pParse, Token *p){
-  Token *pArg = &pParse->sArg;
-  if( pArg->z==0 ){
-    pArg->z = p->z;
-    pArg->n = p->n;
-  }else{
-    assert(pArg->z < p->z);
-    pArg->n = (p->z + p->n - pArg->z);
-  }
+#ifdef YYTRACKMAXSTACKDEPTH
+SQLITE_PRIVATE int sqlite3ParserStackPeak(void *p){
+  yyParser *pParser = (yyParser*)p;
+  return pParser->yyidxMax;
 }
+#endif
 
-/*
-** Invoke a virtual table constructor (either xCreate or xConnect). The
-** pointer to the function to invoke is passed as the fourth parameter
-** to this procedure.
-*/
-static int vtabCallConstructor(
-  sqlite3 *db, 
-  Table *pTab,
-  Module *pMod,
-  int (*xConstruct)(sqlite3*,void*,int,const char*const*,sqlite3_vtab**,char**),
-  char **pzErr
-){
-  int rc;
-  int rc2;
-  sqlite3_vtab *pVtab = 0;
-  const char *const*azArg = (const char *const*)pTab->azModuleArg;
-  int nArg = pTab->nModuleArg;
-  char *zErr = 0;
-  char *zModuleName = sqlite3MPrintf(db, "%s", pTab->zName);
-
-  if( !zModuleName ){
-    return SQLITE_NOMEM;
-  }
-
-  assert( !db->pVTab );
-  assert( xConstruct );
-
-  db->pVTab = pTab;
-  rc = sqlite3SafetyOff(db);
-  assert( rc==SQLITE_OK );
-  rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVtab, &zErr);
-  rc2 = sqlite3SafetyOn(db);
-  if( rc==SQLITE_OK && pVtab ){
-    pVtab->pModule = pMod->pModule;
-    pVtab->nRef = 1;
-    pTab->pVtab = pVtab;
-  }
-
-  if( SQLITE_OK!=rc ){
-    if( zErr==0 ){
-      *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
-    }else {
-      *pzErr = sqlite3MPrintf(db, "%s", zErr);
-      sqlite3_free(zErr);
-    }
-  }else if( db->pVTab ){
-    const char *zFormat = "vtable constructor did not declare schema: %s";
-    *pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
-    rc = SQLITE_ERROR;
-  } 
-  if( rc==SQLITE_OK ){
-    rc = rc2;
-  }
-  db->pVTab = 0;
-  sqlite3_free(zModuleName);
-
-  /* If everything went according to plan, loop through the columns
-  ** of the table to see if any of them contain the token "hidden".
-  ** If so, set the Column.isHidden flag and remove the token from
-  ** the type string.
-  */
-  if( rc==SQLITE_OK ){
-    int iCol;
-    for(iCol=0; iCol<pTab->nCol; iCol++){
-      char *zType = pTab->aCol[iCol].zType;
-      int nType;
-      int i = 0;
-      if( !zType ) continue;
-      nType = strlen(zType);
-      if( sqlite3StrNICmp("hidden", zType, 6) || (zType[6] && zType[6]!=' ') ){
-        for(i=0; i<nType; i++){
-          if( (0==sqlite3StrNICmp(" hidden", &zType[i], 7))
-           && (zType[i+7]=='\0' || zType[i+7]==' ')
-          ){
-            i++;
-            break;
-          }
+/*
+** Find the appropriate action for a parser given the terminal
+** look-ahead token iLookAhead.
+**
+** If the look-ahead token is YYNOCODE, then check to see if the action is
+** independent of the look-ahead.  If it is, return the action, otherwise
+** return YY_NO_ACTION.
+*/
+static int yy_find_shift_action(
+  yyParser *pParser,        /* The parser */
+  YYCODETYPE iLookAhead     /* The look-ahead token */
+){
+  int i;
+  int stateno = pParser->yystack[pParser->yyidx].stateno;
+ 
+  if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
+    return yy_default[stateno];
+  }
+  assert( iLookAhead!=YYNOCODE );
+  i += iLookAhead;
+  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+    /* The user of ";" instead of "\000" as a statement terminator in SQLite
+    ** means that we always have a look-ahead token. */
+    if( iLookAhead>0 ){
+#ifdef YYFALLBACK
+      YYCODETYPE iFallback;            /* Fallback token */
+      if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
+             && (iFallback = yyFallback[iLookAhead])!=0 ){
+#ifndef NDEBUG
+        if( yyTraceFILE ){
+          fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
+             yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
         }
+#endif
+        return yy_find_shift_action(pParser, iFallback);
       }
-      if( i<nType ){
-        int j;
-        int nDel = 6 + (zType[i+6] ? 1 : 0);
-        for(j=i; (j+nDel)<=nType; j++){
-          zType[j] = zType[j+nDel];
-        }
-        if( zType[i]=='\0' && i>0 ){
-          assert(zType[i-1]==' ');
-          zType[i-1] = '\0';
+#endif
+#ifdef YYWILDCARD
+      {
+        int j = i - iLookAhead + YYWILDCARD;
+        if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
+#ifndef NDEBUG
+          if( yyTraceFILE ){
+            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
+               yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]);
+          }
+#endif /* NDEBUG */
+          return yy_action[j];
         }
-        pTab->aCol[iCol].isHidden = 1;
       }
+#endif /* YYWILDCARD */
     }
+    return yy_default[stateno];
+  }else{
+    return yy_action[i];
   }
-  return rc;
 }
 
 /*
-** This function is invoked by the parser to call the xConnect() method
-** of the virtual table pTab. If an error occurs, an error code is returned 
-** and an error left in pParse.
+** Find the appropriate action for a parser given the non-terminal
+** look-ahead token iLookAhead.
 **
-** This call is a no-op if table pTab is not a virtual table.
+** If the look-ahead token is YYNOCODE, then check to see if the action is
+** independent of the look-ahead.  If it is, return the action, otherwise
+** return YY_NO_ACTION.
 */
-SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
-  Module *pMod;
-  int rc = SQLITE_OK;
-
-  if( !pTab || !pTab->isVirtual || pTab->pVtab ){
-    return SQLITE_OK;
+static int yy_find_reduce_action(
+  int stateno,              /* Current state number */
+  YYCODETYPE iLookAhead     /* The look-ahead token */
+){
+  int i;
+#ifdef YYERRORSYMBOL
+  if( stateno>YY_REDUCE_MAX ){
+    return yy_default[stateno];
   }
-
-  pMod = pTab->pMod;
-  if( !pMod ){
-    const char *zModule = pTab->azModuleArg[0];
-    sqlite3ErrorMsg(pParse, "no such module: %s", zModule);
-    rc = SQLITE_ERROR;
-  } else {
-    char *zErr = 0;
-    sqlite3 *db = pParse->db;
-    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xConnect, &zErr);
-    if( rc!=SQLITE_OK ){
-      sqlite3ErrorMsg(pParse, "%s", zErr);
-    }
-    sqlite3_free(zErr);
+#else
+  assert( stateno<=YY_REDUCE_MAX );
+#endif
+  i = yy_reduce_ofst[stateno];
+  assert( i!=YY_REDUCE_USE_DFLT );
+  assert( iLookAhead!=YYNOCODE );
+  i += iLookAhead;
+#ifdef YYERRORSYMBOL
+  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+    return yy_default[stateno];
   }
-
-  return rc;
+#else
+  assert( i>=0 && i<YY_SZ_ACTTAB );
+  assert( yy_lookahead[i]==iLookAhead );
+#endif
+  return yy_action[i];
 }
 
 /*
-** Add the virtual table pVtab to the array sqlite3.aVTrans[].
+** The following routine is called if the stack overflows.
 */
-static int addToVTrans(sqlite3 *db, sqlite3_vtab *pVtab){
-  const int ARRAY_INCR = 5;
-
-  /* Grow the sqlite3.aVTrans array if required */
-  if( (db->nVTrans%ARRAY_INCR)==0 ){
-    sqlite3_vtab **aVTrans;
-    int nBytes = sizeof(sqlite3_vtab *) * (db->nVTrans + ARRAY_INCR);
-    aVTrans = sqlite3DbRealloc(db, (void *)db->aVTrans, nBytes);
-    if( !aVTrans ){
-      return SQLITE_NOMEM;
-    }
-    memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
-    db->aVTrans = aVTrans;
-  }
+static void yyStackOverflow(yyParser *yypParser, YYMINORTYPE *yypMinor){
+   sqlite3ParserARG_FETCH;
+   yypParser->yyidx--;
+#ifndef NDEBUG
+   if( yyTraceFILE ){
+     fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt);
+   }
+#endif
+   while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
+   /* Here code is inserted which will execute if the parser
+   ** stack every overflows */
 
-  /* Add pVtab to the end of sqlite3.aVTrans */
-  db->aVTrans[db->nVTrans++] = pVtab;
-  sqlite3VtabLock(pVtab);
-  return SQLITE_OK;
+  UNUSED_PARAMETER(yypMinor); /* Silence some compiler warnings */
+  sqlite3ErrorMsg(pParse, "parser stack overflow");
+  pParse->parseError = 1;
+   sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument var */
 }
 
 /*
-** This function is invoked by the vdbe to call the xCreate method
-** of the virtual table named zTab in database iDb. 
-**
-** If an error occurs, *pzErr is set to point an an English language
-** description of the error and an SQLITE_XXX error code is returned.
-** In this case the caller must call sqlite3_free() on *pzErr.
+** Perform a shift action.
 */
-SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
-  int rc = SQLITE_OK;
-  Table *pTab;
-  Module *pMod;
-  const char *zModule;
-
-  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
-  assert(pTab && pTab->isVirtual && !pTab->pVtab);
-  pMod = pTab->pMod;
-  zModule = pTab->azModuleArg[0];
-
-  /* If the module has been registered and includes a Create method, 
-  ** invoke it now. If the module has not been registered, return an 
-  ** error. Otherwise, do nothing.
-  */
-  if( !pMod ){
-    *pzErr = sqlite3MPrintf(db, "no such module: %s", zModule);
-    rc = SQLITE_ERROR;
-  }else{
-    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xCreate, pzErr);
+static void yy_shift(
+  yyParser *yypParser,          /* The parser to be shifted */
+  int yyNewState,               /* The new state to shift in */
+  int yyMajor,                  /* The major token to shift in */
+  YYMINORTYPE *yypMinor         /* Pointer to the minor token to shift in */
+){
+  yyStackEntry *yytos;
+  yypParser->yyidx++;
+#ifdef YYTRACKMAXSTACKDEPTH
+  if( yypParser->yyidx>yypParser->yyidxMax ){
+    yypParser->yyidxMax = yypParser->yyidx;
   }
-
-  if( rc==SQLITE_OK && pTab->pVtab ){
-      rc = addToVTrans(db, pTab->pVtab);
+#endif
+#if YYSTACKDEPTH>0 
+  if( yypParser->yyidx>=YYSTACKDEPTH ){
+    yyStackOverflow(yypParser, yypMinor);
+    return;
   }
-
-  return rc;
+#else
+  if( yypParser->yyidx>=yypParser->yystksz ){
+    yyGrowStack(yypParser);
+    if( yypParser->yyidx>=yypParser->yystksz ){
+      yyStackOverflow(yypParser, yypMinor);
+      return;
+    }
+  }
+#endif
+  yytos = &yypParser->yystack[yypParser->yyidx];
+  yytos->stateno = (YYACTIONTYPE)yyNewState;
+  yytos->major = (YYCODETYPE)yyMajor;
+  yytos->minor = *yypMinor;
+#ifndef NDEBUG
+  if( yyTraceFILE && yypParser->yyidx>0 ){
+    int i;
+    fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState);
+    fprintf(yyTraceFILE,"%sStack:",yyTracePrompt);
+    for(i=1; i<=yypParser->yyidx; i++)
+      fprintf(yyTraceFILE," %s",yyTokenName[yypParser->yystack[i].major]);
+    fprintf(yyTraceFILE,"\n");
+  }
+#endif
 }
 
-/*
-** This function is used to set the schema of a virtual table.  It is only
-** valid to call this function from within the xCreate() or xConnect() of a
-** virtual table module.
+/* The following table contains information about every rule that
+** is used during the reduce.
 */
-SQLITE_API int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
-  Parse sParse;
+static const struct {
+  YYCODETYPE lhs;         /* Symbol on the left-hand side of the rule */
+  unsigned char nrhs;     /* Number of right-hand side symbols in the rule */
+} yyRuleInfo[] = {
+  { 142, 1 },
+  { 143, 2 },
+  { 143, 1 },
+  { 144, 1 },
+  { 144, 3 },
+  { 145, 0 },
+  { 145, 1 },
+  { 145, 3 },
+  { 146, 1 },
+  { 147, 3 },
+  { 149, 0 },
+  { 149, 1 },
+  { 149, 2 },
+  { 148, 0 },
+  { 148, 1 },
+  { 148, 1 },
+  { 148, 1 },
+  { 147, 2 },
+  { 147, 2 },
+  { 147, 2 },
+  { 151, 1 },
+  { 151, 0 },
+  { 147, 2 },
+  { 147, 3 },
+  { 147, 5 },
+  { 147, 2 },
+  { 152, 6 },
+  { 154, 1 },
+  { 156, 0 },
+  { 156, 3 },
+  { 155, 1 },
+  { 155, 0 },
+  { 153, 4 },
+  { 153, 2 },
+  { 158, 3 },
+  { 158, 1 },
+  { 161, 3 },
+  { 162, 1 },
+  { 165, 1 },
+  { 165, 1 },
+  { 166, 1 },
+  { 150, 1 },
+  { 150, 1 },
+  { 150, 1 },
+  { 163, 0 },
+  { 163, 1 },
+  { 167, 1 },
+  { 167, 4 },
+  { 167, 6 },
+  { 168, 1 },
+  { 168, 2 },
+  { 169, 1 },
+  { 169, 1 },
+  { 164, 2 },
+  { 164, 0 },
+  { 172, 3 },
+  { 172, 1 },
+  { 173, 2 },
+  { 173, 4 },
+  { 173, 3 },
+  { 173, 3 },
+  { 173, 2 },
+  { 173, 2 },
+  { 173, 3 },
+  { 173, 5 },
+  { 173, 2 },
+  { 173, 4 },
+  { 173, 4 },
+  { 173, 1 },
+  { 173, 2 },
+  { 178, 0 },
+  { 178, 1 },
+  { 180, 0 },
+  { 180, 2 },
+  { 182, 2 },
+  { 182, 3 },
+  { 182, 3 },
+  { 183, 2 },
+  { 183, 2 },
+  { 183, 1 },
+  { 183, 1 },
+  { 183, 2 },
+  { 181, 3 },
+  { 181, 2 },
+  { 184, 0 },
+  { 184, 2 },
+  { 184, 2 },
+  { 159, 0 },
+  { 159, 2 },
+  { 185, 3 },
+  { 185, 2 },
+  { 185, 1 },
+  { 186, 2 },
+  { 186, 7 },
+  { 186, 5 },
+  { 186, 5 },
+  { 186, 10 },
+  { 188, 0 },
+  { 188, 1 },
+  { 176, 0 },
+  { 176, 3 },
+  { 189, 0 },
+  { 189, 2 },
+  { 190, 1 },
+  { 190, 1 },
+  { 190, 1 },
+  { 147, 4 },
+  { 192, 2 },
+  { 192, 0 },
+  { 147, 8 },
+  { 147, 4 },
+  { 147, 1 },
+  { 160, 1 },
+  { 160, 3 },
+  { 195, 1 },
+  { 195, 2 },
+  { 195, 1 },
+  { 194, 9 },
+  { 196, 1 },
+  { 196, 1 },
+  { 196, 0 },
+  { 204, 2 },
+  { 204, 0 },
+  { 197, 3 },
+  { 197, 2 },
+  { 197, 4 },
+  { 205, 2 },
+  { 205, 1 },
+  { 205, 0 },
+  { 198, 0 },
+  { 198, 2 },
+  { 207, 2 },
+  { 207, 0 },
+  { 206, 7 },
+  { 206, 7 },
+  { 206, 7 },
+  { 157, 0 },
+  { 157, 2 },
+  { 193, 2 },
+  { 208, 1 },
+  { 208, 2 },
+  { 208, 3 },
+  { 208, 4 },
+  { 210, 2 },
+  { 210, 0 },
+  { 209, 0 },
+  { 209, 3 },
+  { 209, 2 },
+  { 211, 4 },
+  { 211, 0 },
+  { 202, 0 },
+  { 202, 3 },
+  { 214, 4 },
+  { 214, 2 },
+  { 215, 1 },
+  { 177, 1 },
+  { 177, 1 },
+  { 177, 0 },
+  { 200, 0 },
+  { 200, 3 },
+  { 201, 0 },
+  { 201, 2 },
+  { 203, 0 },
+  { 203, 2 },
+  { 203, 4 },
+  { 203, 4 },
+  { 147, 5 },
+  { 199, 0 },
+  { 199, 2 },
+  { 147, 7 },
+  { 217, 5 },
+  { 217, 3 },
+  { 147, 8 },
+  { 147, 5 },
+  { 147, 6 },
+  { 218, 2 },
+  { 218, 1 },
+  { 220, 3 },
+  { 220, 1 },
+  { 219, 0 },
+  { 219, 3 },
+  { 213, 3 },
+  { 213, 1 },
+  { 175, 1 },
+  { 175, 3 },
+  { 174, 1 },
+  { 175, 1 },
+  { 175, 1 },
+  { 175, 3 },
+  { 175, 5 },
+  { 174, 1 },
+  { 174, 1 },
+  { 175, 1 },
+  { 175, 1 },
+  { 175, 3 },
+  { 175, 6 },
+  { 175, 5 },
+  { 175, 4 },
+  { 174, 1 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 3 },
+  { 222, 1 },
+  { 222, 2 },
+  { 222, 1 },
+  { 222, 2 },
+  { 223, 2 },
+  { 223, 0 },
+  { 175, 4 },
+  { 175, 2 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 4 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 224, 1 },
+  { 224, 2 },
+  { 175, 5 },
+  { 225, 1 },
+  { 225, 2 },
+  { 175, 5 },
+  { 175, 3 },
+  { 175, 5 },
+  { 175, 4 },
+  { 175, 4 },
+  { 175, 5 },
+  { 227, 5 },
+  { 227, 4 },
+  { 228, 2 },
+  { 228, 0 },
+  { 226, 1 },
+  { 226, 0 },
+  { 221, 1 },
+  { 221, 0 },
+  { 216, 3 },
+  { 216, 1 },
+  { 147, 11 },
+  { 229, 1 },
+  { 229, 0 },
+  { 179, 0 },
+  { 179, 3 },
+  { 187, 5 },
+  { 187, 3 },
+  { 230, 0 },
+  { 230, 2 },
+  { 147, 4 },
+  { 147, 1 },
+  { 147, 2 },
+  { 147, 3 },
+  { 147, 5 },
+  { 147, 6 },
+  { 147, 5 },
+  { 147, 6 },
+  { 231, 1 },
+  { 231, 1 },
+  { 231, 1 },
+  { 231, 1 },
+  { 231, 1 },
+  { 170, 2 },
+  { 171, 2 },
+  { 233, 1 },
+  { 232, 1 },
+  { 232, 0 },
+  { 147, 5 },
+  { 234, 11 },
+  { 236, 1 },
+  { 236, 1 },
+  { 236, 2 },
+  { 236, 0 },
+  { 237, 1 },
+  { 237, 1 },
+  { 237, 3 },
+  { 238, 0 },
+  { 238, 3 },
+  { 239, 0 },
+  { 239, 2 },
+  { 235, 3 },
+  { 235, 2 },
+  { 241, 1 },
+  { 241, 3 },
+  { 242, 0 },
+  { 242, 3 },
+  { 242, 2 },
+  { 240, 7 },
+  { 240, 8 },
+  { 240, 5 },
+  { 240, 5 },
+  { 240, 1 },
+  { 175, 4 },
+  { 175, 6 },
+  { 191, 1 },
+  { 191, 1 },
+  { 191, 1 },
+  { 147, 4 },
+  { 147, 6 },
+  { 147, 3 },
+  { 244, 0 },
+  { 244, 2 },
+  { 243, 1 },
+  { 243, 0 },
+  { 147, 1 },
+  { 147, 3 },
+  { 147, 1 },
+  { 147, 3 },
+  { 147, 6 },
+  { 147, 6 },
+  { 245, 1 },
+  { 246, 0 },
+  { 246, 1 },
+  { 147, 1 },
+  { 147, 4 },
+  { 247, 7 },
+  { 248, 1 },
+  { 248, 3 },
+  { 249, 0 },
+  { 249, 2 },
+  { 250, 1 },
+  { 250, 3 },
+  { 251, 1 },
+  { 252, 0 },
+  { 252, 4 },
+  { 252, 2 },
+};
 
-  int rc = SQLITE_OK;
-  Table *pTab;
-  char *zErr = 0;
+static void yy_accept(yyParser*);  /* Forward Declaration */
 
-  sqlite3_mutex_enter(db->mutex);
-  pTab = db->pVTab;
-  if( !pTab ){
-    sqlite3Error(db, SQLITE_MISUSE, 0);
-    sqlite3_mutex_leave(db->mutex);
-    return SQLITE_MISUSE;
+/*
+** Perform a reduce action and the shift that must immediately
+** follow the reduce.
+*/
+static void yy_reduce(
+  yyParser *yypParser,         /* The parser */
+  int yyruleno                 /* Number of the rule by which to reduce */
+){
+  int yygoto;                     /* The next state */
+  int yyact;                      /* The next action */
+  YYMINORTYPE yygotominor;        /* The LHS of the rule reduced */
+  yyStackEntry *yymsp;            /* The top of the parser's stack */
+  int yysize;                     /* Amount to pop the stack */
+  sqlite3ParserARG_FETCH;
+  yymsp = &yypParser->yystack[yypParser->yyidx];
+#ifndef NDEBUG
+  if( yyTraceFILE && yyruleno>=0 
+        && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
+    fprintf(yyTraceFILE, "%sReduce [%s].\n", yyTracePrompt,
+      yyRuleName[yyruleno]);
   }
-  assert(pTab->isVirtual && pTab->nCol==0 && pTab->aCol==0);
-
-  memset(&sParse, 0, sizeof(Parse));
-  sParse.declareVtab = 1;
-  sParse.db = db;
+#endif /* NDEBUG */
 
-  if( 
-      SQLITE_OK == sqlite3RunParser(&sParse, zCreateTable, &zErr) && 
-      sParse.pNewTable && 
-      !sParse.pNewTable->pSelect && 
-      !sParse.pNewTable->isVirtual 
-  ){
-    pTab->aCol = sParse.pNewTable->aCol;
-    pTab->nCol = sParse.pNewTable->nCol;
-    sParse.pNewTable->nCol = 0;
-    sParse.pNewTable->aCol = 0;
-    db->pVTab = 0;
-  } else {
-    sqlite3Error(db, SQLITE_ERROR, zErr);
-    sqlite3_free(zErr);
-    rc = SQLITE_ERROR;
-  }
-  sParse.declareVtab = 0;
+  /* Silence complaints from purify about yygotominor being uninitialized
+  ** in some cases when it is copied into the stack after the following
+  ** switch.  yygotominor is uninitialized when a rule reduces that does
+  ** not set the value of its left-hand side nonterminal.  Leaving the
+  ** value of the nonterminal uninitialized is utterly harmless as long
+  ** as the value is never used.  So really the only thing this code
+  ** accomplishes is to quieten purify.  
+  **
+  ** 2007-01-16:  The wireshark project (www.wireshark.org) reports that
+  ** without this code, their parser segfaults.  I'm not sure what there
+  ** parser is doing to make this happen.  This is the second bug report
+  ** from wireshark this week.  Clearly they are stressing Lemon in ways
+  ** that it has not been previously stressed...  (SQLite ticket #2172)
+  */
+  /*memset(&yygotominor, 0, sizeof(yygotominor));*/
+  yygotominor = yyzerominor;
 
-  sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
-  sqlite3DeleteTable(sParse.pNewTable);
-  sParse.pNewTable = 0;
 
-  assert( (rc&0xff)==rc );
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
+  switch( yyruleno ){
+  /* Beginning here are the reduction cases.  A typical example
+  ** follows:
+  **   case 0:
+  **  #line <lineno> <grammarfile>
+  **     { ... }           // User supplied code
+  **  #line <lineno> <thisfile>
+  **     break;
+  */
+      case 5: /* explain ::= */
+{ sqlite3BeginParse(pParse, 0); }
+        break;
+      case 6: /* explain ::= EXPLAIN */
+{ sqlite3BeginParse(pParse, 1); }
+        break;
+      case 7: /* explain ::= EXPLAIN QUERY PLAN */
+{ sqlite3BeginParse(pParse, 2); }
+        break;
+      case 8: /* cmdx ::= cmd */
+{ sqlite3FinishCoding(pParse); }
+        break;
+      case 9: /* cmd ::= BEGIN transtype trans_opt */
+{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy328);}
+        break;
+      case 13: /* transtype ::= */
+{yygotominor.yy328 = TK_DEFERRED;}
+        break;
+      case 14: /* transtype ::= DEFERRED */
+      case 15: /* transtype ::= IMMEDIATE */ yytestcase(yyruleno==15);
+      case 16: /* transtype ::= EXCLUSIVE */ yytestcase(yyruleno==16);
+      case 114: /* multiselect_op ::= UNION */ yytestcase(yyruleno==114);
+      case 116: /* multiselect_op ::= EXCEPT|INTERSECT */ yytestcase(yyruleno==116);
+{yygotominor.yy328 = yymsp[0].major;}
+        break;
+      case 17: /* cmd ::= COMMIT trans_opt */
+      case 18: /* cmd ::= END trans_opt */ yytestcase(yyruleno==18);
+{sqlite3CommitTransaction(pParse);}
+        break;
+      case 19: /* cmd ::= ROLLBACK trans_opt */
+{sqlite3RollbackTransaction(pParse);}
+        break;
+      case 22: /* cmd ::= SAVEPOINT nm */
+{
+  sqlite3Savepoint(pParse, SAVEPOINT_BEGIN, &yymsp[0].minor.yy0);
+}
+        break;
+      case 23: /* cmd ::= RELEASE savepoint_opt nm */
+{
+  sqlite3Savepoint(pParse, SAVEPOINT_RELEASE, &yymsp[0].minor.yy0);
+}
+        break;
+      case 24: /* cmd ::= ROLLBACK trans_opt TO savepoint_opt nm */
+{
+  sqlite3Savepoint(pParse, SAVEPOINT_ROLLBACK, &yymsp[0].minor.yy0);
+}
+        break;
+      case 26: /* create_table ::= createkw temp TABLE ifnotexists nm dbnm */
+{
+   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy328,0,0,yymsp[-2].minor.yy328);
+}
+        break;
+      case 27: /* createkw ::= CREATE */
+{
+  pParse->db->lookaside.bEnabled = 0;
+  yygotominor.yy0 = yymsp[0].minor.yy0;
+}
+        break;
+      case 28: /* ifnotexists ::= */
+      case 31: /* temp ::= */ yytestcase(yyruleno==31);
+      case 70: /* autoinc ::= */ yytestcase(yyruleno==70);
+      case 82: /* defer_subclause ::= NOT DEFERRABLE init_deferred_pred_opt */ yytestcase(yyruleno==82);
+      case 84: /* init_deferred_pred_opt ::= */ yytestcase(yyruleno==84);
+      case 86: /* init_deferred_pred_opt ::= INITIALLY IMMEDIATE */ yytestcase(yyruleno==86);
+      case 97: /* defer_subclause_opt ::= */ yytestcase(yyruleno==97);
+      case 108: /* ifexists ::= */ yytestcase(yyruleno==108);
+      case 119: /* distinct ::= ALL */ yytestcase(yyruleno==119);
+      case 120: /* distinct ::= */ yytestcase(yyruleno==120);
+      case 222: /* between_op ::= BETWEEN */ yytestcase(yyruleno==222);
+      case 225: /* in_op ::= IN */ yytestcase(yyruleno==225);
+{yygotominor.yy328 = 0;}
+        break;
+      case 29: /* ifnotexists ::= IF NOT EXISTS */
+      case 30: /* temp ::= TEMP */ yytestcase(yyruleno==30);
+      case 71: /* autoinc ::= AUTOINCR */ yytestcase(yyruleno==71);
+      case 85: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */ yytestcase(yyruleno==85);
+      case 107: /* ifexists ::= IF EXISTS */ yytestcase(yyruleno==107);
+      case 118: /* distinct ::= DISTINCT */ yytestcase(yyruleno==118);
+      case 223: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==223);
+      case 226: /* in_op ::= NOT IN */ yytestcase(yyruleno==226);
+{yygotominor.yy328 = 1;}
+        break;
+      case 32: /* create_table_args ::= LP columnlist conslist_opt RP */
+{
+  sqlite3EndTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0);
+}
+        break;
+      case 33: /* create_table_args ::= AS select */
+{
+  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy3);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+}
+        break;
+      case 36: /* column ::= columnid type carglist */
+{
+  yygotominor.yy0.z = yymsp[-2].minor.yy0.z;
+  yygotominor.yy0.n = (int)(pParse->sLastToken.z-yymsp[-2].minor.yy0.z) + pParse->sLastToken.n;
+}
+        break;
+      case 37: /* columnid ::= nm */
+{
+  sqlite3AddColumn(pParse,&yymsp[0].minor.yy0);
+  yygotominor.yy0 = yymsp[0].minor.yy0;
+}
+        break;
+      case 38: /* id ::= ID */
+      case 39: /* id ::= INDEXED */ yytestcase(yyruleno==39);
+      case 40: /* ids ::= ID|STRING */ yytestcase(yyruleno==40);
+      case 41: /* nm ::= id */ yytestcase(yyruleno==41);
+      case 42: /* nm ::= STRING */ yytestcase(yyruleno==42);
+      case 43: /* nm ::= JOIN_KW */ yytestcase(yyruleno==43);
+      case 46: /* typetoken ::= typename */ yytestcase(yyruleno==46);
+      case 49: /* typename ::= ids */ yytestcase(yyruleno==49);
+      case 126: /* as ::= AS nm */ yytestcase(yyruleno==126);
+      case 127: /* as ::= ids */ yytestcase(yyruleno==127);
+      case 137: /* dbnm ::= DOT nm */ yytestcase(yyruleno==137);
+      case 146: /* indexed_opt ::= INDEXED BY nm */ yytestcase(yyruleno==146);
+      case 251: /* collate ::= COLLATE ids */ yytestcase(yyruleno==251);
+      case 260: /* nmnum ::= plus_num */ yytestcase(yyruleno==260);
+      case 261: /* nmnum ::= nm */ yytestcase(yyruleno==261);
+      case 262: /* nmnum ::= ON */ yytestcase(yyruleno==262);
+      case 263: /* nmnum ::= DELETE */ yytestcase(yyruleno==263);
+      case 264: /* nmnum ::= DEFAULT */ yytestcase(yyruleno==264);
+      case 265: /* plus_num ::= plus_opt number */ yytestcase(yyruleno==265);
+      case 266: /* minus_num ::= MINUS number */ yytestcase(yyruleno==266);
+      case 267: /* number ::= INTEGER|FLOAT */ yytestcase(yyruleno==267);
+      case 285: /* trnm ::= nm */ yytestcase(yyruleno==285);
+{yygotominor.yy0 = yymsp[0].minor.yy0;}
+        break;
+      case 45: /* type ::= typetoken */
+{sqlite3AddColumnType(pParse,&yymsp[0].minor.yy0);}
+        break;
+      case 47: /* typetoken ::= typename LP signed RP */
+{
+  yygotominor.yy0.z = yymsp[-3].minor.yy0.z;
+  yygotominor.yy0.n = (int)(&yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-3].minor.yy0.z);
+}
+        break;
+      case 48: /* typetoken ::= typename LP signed COMMA signed RP */
+{
+  yygotominor.yy0.z = yymsp[-5].minor.yy0.z;
+  yygotominor.yy0.n = (int)(&yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-5].minor.yy0.z);
+}
+        break;
+      case 50: /* typename ::= typename ids */
+{yygotominor.yy0.z=yymsp[-1].minor.yy0.z; yygotominor.yy0.n=yymsp[0].minor.yy0.n+(int)(yymsp[0].minor.yy0.z-yymsp[-1].minor.yy0.z);}
+        break;
+      case 57: /* ccons ::= DEFAULT term */
+      case 59: /* ccons ::= DEFAULT PLUS term */ yytestcase(yyruleno==59);
+{sqlite3AddDefaultValue(pParse,&yymsp[0].minor.yy346);}
+        break;
+      case 58: /* ccons ::= DEFAULT LP expr RP */
+{sqlite3AddDefaultValue(pParse,&yymsp[-1].minor.yy346);}
+        break;
+      case 60: /* ccons ::= DEFAULT MINUS term */
+{
+  ExprSpan v;
+  v.pExpr = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy346.pExpr, 0, 0);
+  v.zStart = yymsp[-1].minor.yy0.z;
+  v.zEnd = yymsp[0].minor.yy346.zEnd;
+  sqlite3AddDefaultValue(pParse,&v);
+}
+        break;
+      case 61: /* ccons ::= DEFAULT id */
+{
+  ExprSpan v;
+  spanExpr(&v, pParse, TK_STRING, &yymsp[0].minor.yy0);
+  sqlite3AddDefaultValue(pParse,&v);
+}
+        break;
+      case 63: /* ccons ::= NOT NULL onconf */
+{sqlite3AddNotNull(pParse, yymsp[0].minor.yy328);}
+        break;
+      case 64: /* ccons ::= PRIMARY KEY sortorder onconf autoinc */
+{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy328,yymsp[0].minor.yy328,yymsp[-2].minor.yy328);}
+        break;
+      case 65: /* ccons ::= UNIQUE onconf */
+{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy328,0,0,0,0);}
+        break;
+      case 66: /* ccons ::= CHECK LP expr RP */
+{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy346.pExpr);}
+        break;
+      case 67: /* ccons ::= REFERENCES nm idxlist_opt refargs */
+{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy14,yymsp[0].minor.yy328);}
+        break;
+      case 68: /* ccons ::= defer_subclause */
+{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy328);}
+        break;
+      case 69: /* ccons ::= COLLATE ids */
+{sqlite3AddCollateType(pParse, &yymsp[0].minor.yy0);}
+        break;
+      case 72: /* refargs ::= */
+{ yygotominor.yy328 = OE_None * 0x000101; }
+        break;
+      case 73: /* refargs ::= refargs refarg */
+{ yygotominor.yy328 = (yymsp[-1].minor.yy328 & ~yymsp[0].minor.yy429.mask) | yymsp[0].minor.yy429.value; }
+        break;
+      case 74: /* refarg ::= MATCH nm */
+{ yygotominor.yy429.value = 0;     yygotominor.yy429.mask = 0x000000; }
+        break;
+      case 75: /* refarg ::= ON DELETE refact */
+{ yygotominor.yy429.value = yymsp[0].minor.yy328;     yygotominor.yy429.mask = 0x0000ff; }
+        break;
+      case 76: /* refarg ::= ON UPDATE refact */
+{ yygotominor.yy429.value = yymsp[0].minor.yy328<<8;  yygotominor.yy429.mask = 0x00ff00; }
+        break;
+      case 77: /* refact ::= SET NULL */
+{ yygotominor.yy328 = OE_SetNull; }
+        break;
+      case 78: /* refact ::= SET DEFAULT */
+{ yygotominor.yy328 = OE_SetDflt; }
+        break;
+      case 79: /* refact ::= CASCADE */
+{ yygotominor.yy328 = OE_Cascade; }
+        break;
+      case 80: /* refact ::= RESTRICT */
+{ yygotominor.yy328 = OE_Restrict; }
+        break;
+      case 81: /* refact ::= NO ACTION */
+{ yygotominor.yy328 = OE_None; }
+        break;
+      case 83: /* defer_subclause ::= DEFERRABLE init_deferred_pred_opt */
+      case 98: /* defer_subclause_opt ::= defer_subclause */ yytestcase(yyruleno==98);
+      case 100: /* onconf ::= ON CONFLICT resolvetype */ yytestcase(yyruleno==100);
+      case 103: /* resolvetype ::= raisetype */ yytestcase(yyruleno==103);
+{yygotominor.yy328 = yymsp[0].minor.yy328;}
+        break;
+      case 87: /* conslist_opt ::= */
+{yygotominor.yy0.n = 0; yygotominor.yy0.z = 0;}
+        break;
+      case 88: /* conslist_opt ::= COMMA conslist */
+{yygotominor.yy0 = yymsp[-1].minor.yy0;}
+        break;
+      case 93: /* tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf */
+{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy14,yymsp[0].minor.yy328,yymsp[-2].minor.yy328,0);}
+        break;
+      case 94: /* tcons ::= UNIQUE LP idxlist RP onconf */
+{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy14,yymsp[0].minor.yy328,0,0,0,0);}
+        break;
+      case 95: /* tcons ::= CHECK LP expr RP onconf */
+{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy346.pExpr);}
+        break;
+      case 96: /* tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt */
+{
+    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy14, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy14, yymsp[-1].minor.yy328);
+    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy328);
+}
+        break;
+      case 99: /* onconf ::= */
+{yygotominor.yy328 = OE_Default;}
+        break;
+      case 101: /* orconf ::= */
+{yygotominor.yy186 = OE_Default;}
+        break;
+      case 102: /* orconf ::= OR resolvetype */
+{yygotominor.yy186 = (u8)yymsp[0].minor.yy328;}
+        break;
+      case 104: /* resolvetype ::= IGNORE */
+{yygotominor.yy328 = OE_Ignore;}
+        break;
+      case 105: /* resolvetype ::= REPLACE */
+{yygotominor.yy328 = OE_Replace;}
+        break;
+      case 106: /* cmd ::= DROP TABLE ifexists fullname */
+{
+  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 0, yymsp[-1].minor.yy328);
+}
+        break;
+      case 109: /* cmd ::= createkw temp VIEW ifnotexists nm dbnm AS select */
+{
+  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy3, yymsp[-6].minor.yy328, yymsp[-4].minor.yy328);
+}
+        break;
+      case 110: /* cmd ::= DROP VIEW ifexists fullname */
+{
+  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 1, yymsp[-1].minor.yy328);
+}
+        break;
+      case 111: /* cmd ::= select */
+{
+  SelectDest dest = {SRT_Output, 0, 0, 0, 0};
+  sqlite3Select(pParse, yymsp[0].minor.yy3, &dest);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+}
+        break;
+      case 112: /* select ::= oneselect */
+{yygotominor.yy3 = yymsp[0].minor.yy3;}
+        break;
+      case 113: /* select ::= select multiselect_op oneselect */
+{
+  if( yymsp[0].minor.yy3 ){
+    yymsp[0].minor.yy3->op = (u8)yymsp[-1].minor.yy328;
+    yymsp[0].minor.yy3->pPrior = yymsp[-2].minor.yy3;
+  }else{
+    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy3);
+  }
+  yygotominor.yy3 = yymsp[0].minor.yy3;
+}
+        break;
+      case 115: /* multiselect_op ::= UNION ALL */
+{yygotominor.yy328 = TK_ALL;}
+        break;
+      case 117: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
+{
+  yygotominor.yy3 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy14,yymsp[-5].minor.yy65,yymsp[-4].minor.yy132,yymsp[-3].minor.yy14,yymsp[-2].minor.yy132,yymsp[-1].minor.yy14,yymsp[-7].minor.yy328,yymsp[0].minor.yy476.pLimit,yymsp[0].minor.yy476.pOffset);
+}
+        break;
+      case 121: /* sclp ::= selcollist COMMA */
+      case 247: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==247);
+{yygotominor.yy14 = yymsp[-1].minor.yy14;}
+        break;
+      case 122: /* sclp ::= */
+      case 150: /* orderby_opt ::= */ yytestcase(yyruleno==150);
+      case 158: /* groupby_opt ::= */ yytestcase(yyruleno==158);
+      case 240: /* exprlist ::= */ yytestcase(yyruleno==240);
+      case 246: /* idxlist_opt ::= */ yytestcase(yyruleno==246);
+{yygotominor.yy14 = 0;}
+        break;
+      case 123: /* selcollist ::= sclp expr as */
+{
+   yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-2].minor.yy14, yymsp[-1].minor.yy346.pExpr);
+   if( yymsp[0].minor.yy0.n>0 ) sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[0].minor.yy0, 1);
+   sqlite3ExprListSetSpan(pParse,yygotominor.yy14,&yymsp[-1].minor.yy346);
+}
+        break;
+      case 124: /* selcollist ::= sclp STAR */
+{
+  Expr *p = sqlite3Expr(pParse->db, TK_ALL, 0);
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy14, p);
+}
+        break;
+      case 125: /* selcollist ::= sclp nm DOT STAR */
+{
+  Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, &yymsp[0].minor.yy0);
+  Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
+  Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14, pDot);
+}
+        break;
+      case 128: /* as ::= */
+{yygotominor.yy0.n = 0;}
+        break;
+      case 129: /* from ::= */
+{yygotominor.yy65 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy65));}
+        break;
+      case 130: /* from ::= FROM seltablist */
+{
+  yygotominor.yy65 = yymsp[0].minor.yy65;
+  sqlite3SrcListShiftJoinType(yygotominor.yy65);
 }
-
-/*
-** This function is invoked by the vdbe to call the xDestroy method
-** of the virtual table named zTab in database iDb. This occurs
-** when a DROP TABLE is mentioned.
-**
-** This call is a no-op if zTab is not a virtual table.
-*/
-SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab)
+        break;
+      case 131: /* stl_prefix ::= seltablist joinop */
 {
-  int rc = SQLITE_OK;
-  Table *pTab;
-
-  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
-  assert(pTab);
-  if( pTab->pVtab ){
-    int (*xDestroy)(sqlite3_vtab *pVTab) = pTab->pMod->pModule->xDestroy;
-    rc = sqlite3SafetyOff(db);
-    assert( rc==SQLITE_OK );
-    if( xDestroy ){
-      rc = xDestroy(pTab->pVtab);
-    }
-    (void)sqlite3SafetyOn(db);
-    if( rc==SQLITE_OK ){
-      int i;
-      for(i=0; i<db->nVTrans; i++){
-        if( db->aVTrans[i]==pTab->pVtab ){
-          db->aVTrans[i] = db->aVTrans[--db->nVTrans];
-          break;
-        }
-      }
-      pTab->pVtab = 0;
-    }
-  }
-
-  return rc;
+   yygotominor.yy65 = yymsp[-1].minor.yy65;
+   if( ALWAYS(yygotominor.yy65 && yygotominor.yy65->nSrc>0) ) yygotominor.yy65->a[yygotominor.yy65->nSrc-1].jointype = (u8)yymsp[0].minor.yy328;
 }
-
-/*
-** This function invokes either the xRollback or xCommit method
-** of each of the virtual tables in the sqlite3.aVTrans array. The method
-** called is identified by the second argument, "offset", which is
-** the offset of the method to call in the sqlite3_module structure.
-**
-** The array is cleared after invoking the callbacks. 
-*/
-static void callFinaliser(sqlite3 *db, int offset){
-  int i;
-  if( db->aVTrans ){
-    for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
-      sqlite3_vtab *pVtab = db->aVTrans[i];
-      int (*x)(sqlite3_vtab *);
-      x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
-      if( x ) x(pVtab);
-      sqlite3VtabUnlock(db, pVtab);
-    }
-    sqlite3_free(db->aVTrans);
-    db->nVTrans = 0;
-    db->aVTrans = 0;
-  }
+        break;
+      case 132: /* stl_prefix ::= */
+{yygotominor.yy65 = 0;}
+        break;
+      case 133: /* seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt */
+{
+  yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+  sqlite3SrcListIndexedBy(pParse, yygotominor.yy65, &yymsp[-2].minor.yy0);
 }
-
-/*
-** If argument rc2 is not SQLITE_OK, then return it and do nothing. 
-** Otherwise, invoke the xSync method of all virtual tables in the 
-** sqlite3.aVTrans array. Return the error code for the first error 
-** that occurs, or SQLITE_OK if all xSync operations are successful.
-*/
-SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, int rc2){
-  int i;
-  int rc = SQLITE_OK;
-  int rcsafety;
-  sqlite3_vtab **aVTrans = db->aVTrans;
-  if( rc2!=SQLITE_OK ) return rc2;
-
-  rc = sqlite3SafetyOff(db);
-  db->aVTrans = 0;
-  for(i=0; rc==SQLITE_OK && i<db->nVTrans && aVTrans[i]; i++){
-    sqlite3_vtab *pVtab = aVTrans[i];
-    int (*x)(sqlite3_vtab *);
-    x = pVtab->pModule->xSync;
-    if( x ){
-      rc = x(pVtab);
+        break;
+      case 134: /* seltablist ::= stl_prefix LP select RP as on_opt using_opt */
+{
+    yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy3,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+  }
+        break;
+      case 135: /* seltablist ::= stl_prefix LP seltablist RP as on_opt using_opt */
+{
+    if( yymsp[-6].minor.yy65==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy132==0 && yymsp[0].minor.yy408==0 ){
+      yygotominor.yy65 = yymsp[-4].minor.yy65;
+    }else{
+      Select *pSubquery;
+      sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy65);
+      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy65,0,0,0,0,0,0,0);
+      yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
     }
   }
-  db->aVTrans = aVTrans;
-  rcsafety = sqlite3SafetyOn(db);
-
-  if( rc==SQLITE_OK ){
-    rc = rcsafety;
+        break;
+      case 136: /* dbnm ::= */
+      case 145: /* indexed_opt ::= */ yytestcase(yyruleno==145);
+{yygotominor.yy0.z=0; yygotominor.yy0.n=0;}
+        break;
+      case 138: /* fullname ::= nm dbnm */
+{yygotominor.yy65 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
+        break;
+      case 139: /* joinop ::= COMMA|JOIN */
+{ yygotominor.yy328 = JT_INNER; }
+        break;
+      case 140: /* joinop ::= JOIN_KW JOIN */
+{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
+        break;
+      case 141: /* joinop ::= JOIN_KW nm JOIN */
+{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
+        break;
+      case 142: /* joinop ::= JOIN_KW nm nm JOIN */
+{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
+        break;
+      case 143: /* on_opt ::= ON expr */
+      case 154: /* sortitem ::= expr */ yytestcase(yyruleno==154);
+      case 161: /* having_opt ::= HAVING expr */ yytestcase(yyruleno==161);
+      case 168: /* where_opt ::= WHERE expr */ yytestcase(yyruleno==168);
+      case 235: /* case_else ::= ELSE expr */ yytestcase(yyruleno==235);
+      case 237: /* case_operand ::= expr */ yytestcase(yyruleno==237);
+{yygotominor.yy132 = yymsp[0].minor.yy346.pExpr;}
+        break;
+      case 144: /* on_opt ::= */
+      case 160: /* having_opt ::= */ yytestcase(yyruleno==160);
+      case 167: /* where_opt ::= */ yytestcase(yyruleno==167);
+      case 236: /* case_else ::= */ yytestcase(yyruleno==236);
+      case 238: /* case_operand ::= */ yytestcase(yyruleno==238);
+{yygotominor.yy132 = 0;}
+        break;
+      case 147: /* indexed_opt ::= NOT INDEXED */
+{yygotominor.yy0.z=0; yygotominor.yy0.n=1;}
+        break;
+      case 148: /* using_opt ::= USING LP inscollist RP */
+      case 180: /* inscollist_opt ::= LP inscollist RP */ yytestcase(yyruleno==180);
+{yygotominor.yy408 = yymsp[-1].minor.yy408;}
+        break;
+      case 149: /* using_opt ::= */
+      case 179: /* inscollist_opt ::= */ yytestcase(yyruleno==179);
+{yygotominor.yy408 = 0;}
+        break;
+      case 151: /* orderby_opt ::= ORDER BY sortlist */
+      case 159: /* groupby_opt ::= GROUP BY nexprlist */ yytestcase(yyruleno==159);
+      case 239: /* exprlist ::= nexprlist */ yytestcase(yyruleno==239);
+{yygotominor.yy14 = yymsp[0].minor.yy14;}
+        break;
+      case 152: /* sortlist ::= sortlist COMMA sortitem sortorder */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14,yymsp[-1].minor.yy132);
+  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+}
+        break;
+      case 153: /* sortlist ::= sortitem sortorder */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy132);
+  if( yygotominor.yy14 && ALWAYS(yygotominor.yy14->a) ) yygotominor.yy14->a[0].sortOrder = (u8)yymsp[0].minor.yy328;
+}
+        break;
+      case 155: /* sortorder ::= ASC */
+      case 157: /* sortorder ::= */ yytestcase(yyruleno==157);
+{yygotominor.yy328 = SQLITE_SO_ASC;}
+        break;
+      case 156: /* sortorder ::= DESC */
+{yygotominor.yy328 = SQLITE_SO_DESC;}
+        break;
+      case 162: /* limit_opt ::= */
+{yygotominor.yy476.pLimit = 0; yygotominor.yy476.pOffset = 0;}
+        break;
+      case 163: /* limit_opt ::= LIMIT expr */
+{yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr; yygotominor.yy476.pOffset = 0;}
+        break;
+      case 164: /* limit_opt ::= LIMIT expr OFFSET expr */
+{yygotominor.yy476.pLimit = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pOffset = yymsp[0].minor.yy346.pExpr;}
+        break;
+      case 165: /* limit_opt ::= LIMIT expr COMMA expr */
+{yygotominor.yy476.pOffset = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr;}
+        break;
+      case 166: /* cmd ::= DELETE FROM fullname indexed_opt where_opt */
+{
+  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy65, &yymsp[-1].minor.yy0);
+  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy65,yymsp[0].minor.yy132);
+}
+        break;
+      case 169: /* cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt */
+{
+  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy65, &yymsp[-3].minor.yy0);
+  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy14,"set list"); 
+  sqlite3Update(pParse,yymsp[-4].minor.yy65,yymsp[-1].minor.yy14,yymsp[0].minor.yy132,yymsp[-5].minor.yy186);
+}
+        break;
+      case 170: /* setlist ::= setlist COMMA nm EQ expr */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-4].minor.yy14, yymsp[0].minor.yy346.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+}
+        break;
+      case 171: /* setlist ::= nm EQ expr */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse, 0, yymsp[0].minor.yy346.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+}
+        break;
+      case 172: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
+{sqlite3Insert(pParse, yymsp[-5].minor.yy65, yymsp[-1].minor.yy14, 0, yymsp[-4].minor.yy408, yymsp[-7].minor.yy186);}
+        break;
+      case 173: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
+{sqlite3Insert(pParse, yymsp[-2].minor.yy65, 0, yymsp[0].minor.yy3, yymsp[-1].minor.yy408, yymsp[-4].minor.yy186);}
+        break;
+      case 174: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
+{sqlite3Insert(pParse, yymsp[-3].minor.yy65, 0, 0, yymsp[-2].minor.yy408, yymsp[-5].minor.yy186);}
+        break;
+      case 175: /* insert_cmd ::= INSERT orconf */
+{yygotominor.yy186 = yymsp[0].minor.yy186;}
+        break;
+      case 176: /* insert_cmd ::= REPLACE */
+{yygotominor.yy186 = OE_Replace;}
+        break;
+      case 177: /* itemlist ::= itemlist COMMA expr */
+      case 241: /* nexprlist ::= nexprlist COMMA expr */ yytestcase(yyruleno==241);
+{yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy14,yymsp[0].minor.yy346.pExpr);}
+        break;
+      case 178: /* itemlist ::= expr */
+      case 242: /* nexprlist ::= expr */ yytestcase(yyruleno==242);
+{yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy346.pExpr);}
+        break;
+      case 181: /* inscollist ::= inscollist COMMA nm */
+{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy408,&yymsp[0].minor.yy0);}
+        break;
+      case 182: /* inscollist ::= nm */
+{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
+        break;
+      case 183: /* expr ::= term */
+      case 211: /* escape ::= ESCAPE expr */ yytestcase(yyruleno==211);
+{yygotominor.yy346 = yymsp[0].minor.yy346;}
+        break;
+      case 184: /* expr ::= LP expr RP */
+{yygotominor.yy346.pExpr = yymsp[-1].minor.yy346.pExpr; spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);}
+        break;
+      case 185: /* term ::= NULL */
+      case 190: /* term ::= INTEGER|FLOAT|BLOB */ yytestcase(yyruleno==190);
+      case 191: /* term ::= STRING */ yytestcase(yyruleno==191);
+{spanExpr(&yygotominor.yy346, pParse, yymsp[0].major, &yymsp[0].minor.yy0);}
+        break;
+      case 186: /* expr ::= id */
+      case 187: /* expr ::= JOIN_KW */ yytestcase(yyruleno==187);
+{spanExpr(&yygotominor.yy346, pParse, TK_ID, &yymsp[0].minor.yy0);}
+        break;
+      case 188: /* expr ::= nm DOT nm */
+{
+  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
+  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
+  spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
+}
+        break;
+      case 189: /* expr ::= nm DOT nm DOT nm */
+{
+  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-4].minor.yy0);
+  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
+  Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
+  Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
+  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+}
+        break;
+      case 192: /* expr ::= REGISTER */
+{
+  /* When doing a nested parse, one can include terms in an expression
+  ** that look like this:   #1 #2 ...  These terms refer to registers
+  ** in the virtual machine.  #N is the N-th register. */
+  if( pParse->nested==0 ){
+    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &yymsp[0].minor.yy0);
+    yygotominor.yy346.pExpr = 0;
+  }else{
+    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, &yymsp[0].minor.yy0);
+    if( yygotominor.yy346.pExpr ) sqlite3GetInt32(&yymsp[0].minor.yy0.z[1], &yygotominor.yy346.pExpr->iTable);
   }
-  return rc;
+  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
-
-/*
-** Invoke the xRollback method of all virtual tables in the 
-** sqlite3.aVTrans array. Then clear the array itself.
-*/
-SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db){
-  callFinaliser(db, offsetof(sqlite3_module,xRollback));
-  return SQLITE_OK;
+        break;
+      case 193: /* expr ::= VARIABLE */
+{
+  spanExpr(&yygotominor.yy346, pParse, TK_VARIABLE, &yymsp[0].minor.yy0);
+  sqlite3ExprAssignVarNumber(pParse, yygotominor.yy346.pExpr);
+  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
-
-/*
-** Invoke the xCommit method of all virtual tables in the 
-** sqlite3.aVTrans array. Then clear the array itself.
-*/
-SQLITE_PRIVATE int sqlite3VtabCommit(sqlite3 *db){
-  callFinaliser(db, offsetof(sqlite3_module,xCommit));
-  return SQLITE_OK;
+        break;
+      case 194: /* expr ::= expr COLLATE ids */
+{
+  yygotominor.yy346.pExpr = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy346.pExpr, &yymsp[0].minor.yy0);
+  yygotominor.yy346.zStart = yymsp[-2].minor.yy346.zStart;
+  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
-
-/*
-** If the virtual table pVtab supports the transaction interface
-** (xBegin/xRollback/xCommit and optionally xSync) and a transaction is
-** not currently open, invoke the xBegin method now.
-**
-** If the xBegin call is successful, place the sqlite3_vtab pointer
-** in the sqlite3.aVTrans array.
-*/
-SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *db, sqlite3_vtab *pVtab){
-  int rc = SQLITE_OK;
-  const sqlite3_module *pModule;
-
-  /* Special case: If db->aVTrans is NULL and db->nVTrans is greater
-  ** than zero, then this function is being called from within a
-  ** virtual module xSync() callback. It is illegal to write to 
-  ** virtual module tables in this case, so return SQLITE_LOCKED.
-  */
-  if( 0==db->aVTrans && db->nVTrans>0 ){
-    return SQLITE_LOCKED;
+        break;
+      case 195: /* expr ::= CAST LP expr AS typetoken RP */
+{
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy346.pExpr, 0, &yymsp[-1].minor.yy0);
+  spanSet(&yygotominor.yy346,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
+}
+        break;
+      case 196: /* expr ::= ID LP distinct exprlist RP */
+{
+  if( yymsp[-1].minor.yy14 && yymsp[-1].minor.yy14->nExpr>pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){
+    sqlite3ErrorMsg(pParse, "too many arguments on function %T", &yymsp[-4].minor.yy0);
   }
-  if( !pVtab ){
-    return SQLITE_OK;
-  } 
-  pModule = pVtab->pModule;
-
-  if( pModule->xBegin ){
-    int i;
-
-
-    /* If pVtab is already in the aVTrans array, return early */
-    for(i=0; (i<db->nVTrans) && 0!=db->aVTrans[i]; i++){
-      if( db->aVTrans[i]==pVtab ){
-        return SQLITE_OK;
-      }
-    }
-
-    /* Invoke the xBegin method */
-    rc = pModule->xBegin(pVtab);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-
-    rc = addToVTrans(db, pVtab);
+  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy14, &yymsp[-4].minor.yy0);
+  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  if( yymsp[-2].minor.yy328 && yygotominor.yy346.pExpr ){
+    yygotominor.yy346.pExpr->flags |= EP_Distinct;
   }
-  return rc;
 }
-
-/*
-** The first parameter (pDef) is a function implementation.  The
-** second parameter (pExpr) is the first argument to this function.
-** If pExpr is a column in a virtual table, then let the virtual
-** table implementation have an opportunity to overload the function.
-**
-** This routine is used to allow virtual table implementations to
-** overload MATCH, LIKE, GLOB, and REGEXP operators.
-**
-** Return either the pDef argument (indicating no change) or a 
-** new FuncDef structure that is marked as ephemeral using the
-** SQLITE_FUNC_EPHEM flag.
-*/
-SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
-  sqlite3 *db,    /* Database connection for reporting malloc problems */
-  FuncDef *pDef,  /* Function to possibly overload */
-  int nArg,       /* Number of arguments to the function */
-  Expr *pExpr     /* First argument to the function */
-){
-  Table *pTab;
-  sqlite3_vtab *pVtab;
-  sqlite3_module *pMod;
-  void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
-  void *pArg;
-  FuncDef *pNew;
-  int rc = 0;
-  char *zLowerName;
-  unsigned char *z;
-
-
-  /* Check to see the left operand is a column in a virtual table */
-  if( pExpr==0 ) return pDef;
-  if( pExpr->op!=TK_COLUMN ) return pDef;
-  pTab = pExpr->pTab;
-  if( pTab==0 ) return pDef;
-  if( !pTab->isVirtual ) return pDef;
-  pVtab = pTab->pVtab;
-  assert( pVtab!=0 );
-  assert( pVtab->pModule!=0 );
-  pMod = (sqlite3_module *)pVtab->pModule;
-  if( pMod->xFindFunction==0 ) return pDef;
- 
-  /* Call the xFindFunction method on the virtual table implementation
-  ** to see if the implementation wants to overload this function 
-  */
-  zLowerName = sqlite3DbStrDup(db, pDef->zName);
-  if( zLowerName ){
-    for(z=(unsigned char*)zLowerName; *z; z++){
-      *z = sqlite3UpperToLower[*z];
-    }
-    rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
-    sqlite3_free(zLowerName);
-  }
-  if( rc==0 ){
-    return pDef;
+        break;
+      case 197: /* expr ::= ID LP STAR RP */
+{
+  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
+  spanSet(&yygotominor.yy346,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
+}
+        break;
+      case 198: /* term ::= CTIME_KW */
+{
+  /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
+  ** treated as functions that return constants */
+  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
+  if( yygotominor.yy346.pExpr ){
+    yygotominor.yy346.pExpr->op = TK_CONST_FUNC;  
   }
-
-  /* Create a new ephemeral function definition for the overloaded
-  ** function */
-  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) + strlen(pDef->zName) );
-  if( pNew==0 ){
-    return pDef;
+  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+}
+        break;
+      case 199: /* expr ::= expr AND expr */
+      case 200: /* expr ::= expr OR expr */ yytestcase(yyruleno==200);
+      case 201: /* expr ::= expr LT|GT|GE|LE expr */ yytestcase(yyruleno==201);
+      case 202: /* expr ::= expr EQ|NE expr */ yytestcase(yyruleno==202);
+      case 203: /* expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr */ yytestcase(yyruleno==203);
+      case 204: /* expr ::= expr PLUS|MINUS expr */ yytestcase(yyruleno==204);
+      case 205: /* expr ::= expr STAR|SLASH|REM expr */ yytestcase(yyruleno==205);
+      case 206: /* expr ::= expr CONCAT expr */ yytestcase(yyruleno==206);
+{spanBinaryExpr(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);}
+        break;
+      case 207: /* likeop ::= LIKE_KW */
+      case 209: /* likeop ::= MATCH */ yytestcase(yyruleno==209);
+{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 0;}
+        break;
+      case 208: /* likeop ::= NOT LIKE_KW */
+      case 210: /* likeop ::= NOT MATCH */ yytestcase(yyruleno==210);
+{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 1;}
+        break;
+      case 212: /* escape ::= */
+{memset(&yygotominor.yy346,0,sizeof(yygotominor.yy346));}
+        break;
+      case 213: /* expr ::= expr likeop expr escape */
+{
+  ExprList *pList;
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy346.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy346.pExpr);
+  if( yymsp[0].minor.yy346.pExpr ){
+    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
   }
-  *pNew = *pDef;
-  memcpy(pNew->zName, pDef->zName, strlen(pDef->zName)+1);
-  pNew->xFunc = xFunc;
-  pNew->pUserData = pArg;
-  pNew->flags |= SQLITE_FUNC_EPHEM;
-  return pNew;
+  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy96.eOperator);
+  if( yymsp[-2].minor.yy96.not ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
+  yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
+  yygotominor.yy346.zEnd = yymsp[-1].minor.yy346.zEnd;
+  if( yygotominor.yy346.pExpr ) yygotominor.yy346.pExpr->flags |= EP_InfixFunc;
 }
-
-/*
-** Make sure virtual table pTab is contained in the pParse->apVirtualLock[]
-** array so that an OP_VBegin will get generated for it.  Add pTab to the
-** array if it is missing.  If pTab is already in the array, this routine
-** is a no-op.
-*/
-SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse *pParse, Table *pTab){
-  int i, n;
-  assert( IsVirtual(pTab) );
-  for(i=0; i<pParse->nVtabLock; i++){
-    if( pTab==pParse->apVtabLock[i] ) return;
+        break;
+      case 214: /* expr ::= expr ISNULL|NOTNULL */
+{spanUnaryPostfix(&yygotominor.yy346,pParse,yymsp[0].major,&yymsp[-1].minor.yy346,&yymsp[0].minor.yy0);}
+        break;
+      case 215: /* expr ::= expr NOT NULL */
+{spanUnaryPostfix(&yygotominor.yy346,pParse,TK_NOTNULL,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy0);}
+        break;
+      case 216: /* expr ::= expr IS expr */
+{
+  spanBinaryExpr(&yygotominor.yy346,pParse,TK_IS,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);
+  if( pParse->db->mallocFailed==0  && yymsp[0].minor.yy346.pExpr->op==TK_NULL ){
+    yygotominor.yy346.pExpr->op = TK_ISNULL;
   }
-  n = (pParse->nVtabLock+1)*sizeof(pParse->apVtabLock[0]);
-  pParse->apVtabLock = sqlite3_realloc(pParse->apVtabLock, n);
-  if( pParse->apVtabLock ){
-    pParse->apVtabLock[pParse->nVtabLock++] = pTab;
-  }else{
-    pParse->db->mallocFailed = 1;
+}
+        break;
+      case 217: /* expr ::= expr IS NOT expr */
+{
+  spanBinaryExpr(&yygotominor.yy346,pParse,TK_ISNOT,&yymsp[-3].minor.yy346,&yymsp[0].minor.yy346);
+  if( pParse->db->mallocFailed==0  && yymsp[0].minor.yy346.pExpr->op==TK_NULL ){
+    yygotominor.yy346.pExpr->op = TK_NOTNULL;
   }
 }
-
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-/************** End of vtab.c ************************************************/
-/************** Begin file where.c *******************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This module contains C code that generates VDBE code used to process
-** the WHERE clause of SQL statements.  This module is reponsible for
-** generating the code that loops through a table looking for applicable
-** rows.  Indices are selected and used to speed the search when doing
-** so is applicable.  Because this module is responsible for selecting
-** indices, you might also think of this module as the "query optimizer".
-**
-** $Id: where.c,v 1.302 2008/04/19 14:40:44 drh Exp $
-*/
-
-/*
-** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
-*/
-#define BMS  (sizeof(Bitmask)*8)
-
-/*
-** Trace output macros
-*/
-#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
-SQLITE_PRIVATE int sqlite3WhereTrace = 0;
-# define WHERETRACE(X)  if(sqlite3WhereTrace) sqlite3DebugPrintf X
-#else
-# define WHERETRACE(X)
-#endif
-
-/* Forward reference
-*/
-typedef struct WhereClause WhereClause;
-typedef struct ExprMaskSet ExprMaskSet;
-
-/*
-** The query generator uses an array of instances of this structure to
-** help it analyze the subexpressions of the WHERE clause.  Each WHERE
-** clause subexpression is separated from the others by an AND operator.
-**
-** All WhereTerms are collected into a single WhereClause structure.  
-** The following identity holds:
-**
-**        WhereTerm.pWC->a[WhereTerm.idx] == WhereTerm
-**
-** When a term is of the form:
-**
-**              X <op> <expr>
-**
-** where X is a column name and <op> is one of certain operators,
-** then WhereTerm.leftCursor and WhereTerm.leftColumn record the
-** cursor number and column number for X.  WhereTerm.operator records
-** the <op> using a bitmask encoding defined by WO_xxx below.  The
-** use of a bitmask encoding for the operator allows us to search
-** quickly for terms that match any of several different operators.
-**
-** prereqRight and prereqAll record sets of cursor numbers,
-** but they do so indirectly.  A single ExprMaskSet structure translates
-** cursor number into bits and the translated bit is stored in the prereq
-** fields.  The translation is used in order to maximize the number of
-** bits that will fit in a Bitmask.  The VDBE cursor numbers might be
-** spread out over the non-negative integers.  For example, the cursor
-** numbers might be 3, 8, 9, 10, 20, 23, 41, and 45.  The ExprMaskSet
-** translates these sparse cursor numbers into consecutive integers
-** beginning with 0 in order to make the best possible use of the available
-** bits in the Bitmask.  So, in the example above, the cursor numbers
-** would be mapped into integers 0 through 7.
-*/
-typedef struct WhereTerm WhereTerm;
-struct WhereTerm {
-  Expr *pExpr;            /* Pointer to the subexpression */
-  i16 iParent;            /* Disable pWC->a[iParent] when this term disabled */
-  i16 leftCursor;         /* Cursor number of X in "X <op> <expr>" */
-  i16 leftColumn;         /* Column number of X in "X <op> <expr>" */
-  u16 eOperator;          /* A WO_xx value describing <op> */
-  u8 flags;               /* Bit flags.  See below */
-  u8 nChild;              /* Number of children that must disable us */
-  WhereClause *pWC;       /* The clause this term is part of */
-  Bitmask prereqRight;    /* Bitmask of tables used by pRight */
-  Bitmask prereqAll;      /* Bitmask of tables referenced by p */
-};
-
-/*
-** Allowed values of WhereTerm.flags
-*/
-#define TERM_DYNAMIC    0x01   /* Need to call sqlite3ExprDelete(pExpr) */
-#define TERM_VIRTUAL    0x02   /* Added by the optimizer.  Do not code */
-#define TERM_CODED      0x04   /* This term is already coded */
-#define TERM_COPIED     0x08   /* Has a child */
-#define TERM_OR_OK      0x10   /* Used during OR-clause processing */
-
-/*
-** An instance of the following structure holds all information about a
-** WHERE clause.  Mostly this is a container for one or more WhereTerms.
-*/
-struct WhereClause {
-  Parse *pParse;           /* The parser context */
-  ExprMaskSet *pMaskSet;   /* Mapping of table indices to bitmasks */
-  int nTerm;               /* Number of terms */
-  int nSlot;               /* Number of entries in a[] */
-  WhereTerm *a;            /* Each a[] describes a term of the WHERE cluase */
-  WhereTerm aStatic[10];   /* Initial static space for a[] */
-};
-
-/*
-** An instance of the following structure keeps track of a mapping
-** between VDBE cursor numbers and bits of the bitmasks in WhereTerm.
-**
-** The VDBE cursor numbers are small integers contained in 
-** SrcList_item.iCursor and Expr.iTable fields.  For any given WHERE 
-** clause, the cursor numbers might not begin with 0 and they might
-** contain gaps in the numbering sequence.  But we want to make maximum
-** use of the bits in our bitmasks.  This structure provides a mapping
-** from the sparse cursor numbers into consecutive integers beginning
-** with 0.
-**
-** If ExprMaskSet.ix[A]==B it means that The A-th bit of a Bitmask
-** corresponds VDBE cursor number B.  The A-th bit of a bitmask is 1<<A.
-**
-** For example, if the WHERE clause expression used these VDBE
-** cursors:  4, 5, 8, 29, 57, 73.  Then the  ExprMaskSet structure
-** would map those cursor numbers into bits 0 through 5.
-**
-** Note that the mapping is not necessarily ordered.  In the example
-** above, the mapping might go like this:  4->3, 5->1, 8->2, 29->0,
-** 57->5, 73->4.  Or one of 719 other combinations might be used. It
-** does not really matter.  What is important is that sparse cursor
-** numbers all get mapped into bit numbers that begin with 0 and contain
-** no gaps.
-*/
-struct ExprMaskSet {
-  int n;                        /* Number of assigned cursor values */
-  int ix[sizeof(Bitmask)*8];    /* Cursor assigned to each bit */
-};
-
-
-/*
-** Bitmasks for the operators that indices are able to exploit.  An
-** OR-ed combination of these values can be used when searching for
-** terms in the where clause.
-*/
-#define WO_IN     1
-#define WO_EQ     2
-#define WO_LT     (WO_EQ<<(TK_LT-TK_EQ))
-#define WO_LE     (WO_EQ<<(TK_LE-TK_EQ))
-#define WO_GT     (WO_EQ<<(TK_GT-TK_EQ))
-#define WO_GE     (WO_EQ<<(TK_GE-TK_EQ))
-#define WO_MATCH  64
-#define WO_ISNULL 128
-
-/*
-** Value for flags returned by bestIndex().  
-**
-** The least significant byte is reserved as a mask for WO_ values above.
-** The WhereLevel.flags field is usually set to WO_IN|WO_EQ|WO_ISNULL.
-** But if the table is the right table of a left join, WhereLevel.flags
-** is set to WO_IN|WO_EQ.  The WhereLevel.flags field can then be used as
-** the "op" parameter to findTerm when we are resolving equality constraints.
-** ISNULL constraints will then not be used on the right table of a left
-** join.  Tickets #2177 and #2189.
-*/
-#define WHERE_ROWID_EQ     0x000100   /* rowid=EXPR or rowid IN (...) */
-#define WHERE_ROWID_RANGE  0x000200   /* rowid<EXPR and/or rowid>EXPR */
-#define WHERE_COLUMN_EQ    0x001000   /* x=EXPR or x IN (...) */
-#define WHERE_COLUMN_RANGE 0x002000   /* x<EXPR and/or x>EXPR */
-#define WHERE_COLUMN_IN    0x004000   /* x IN (...) */
-#define WHERE_TOP_LIMIT    0x010000   /* x<EXPR or x<=EXPR constraint */
-#define WHERE_BTM_LIMIT    0x020000   /* x>EXPR or x>=EXPR constraint */
-#define WHERE_IDX_ONLY     0x080000   /* Use index only - omit table */
-#define WHERE_ORDERBY      0x100000   /* Output will appear in correct order */
-#define WHERE_REVERSE      0x200000   /* Scan in reverse order */
-#define WHERE_UNIQUE       0x400000   /* Selects no more than one row */
-#define WHERE_VIRTUALTABLE 0x800000   /* Use virtual-table processing */
-
-/*
-** Initialize a preallocated WhereClause structure.
-*/
-static void whereClauseInit(
-  WhereClause *pWC,        /* The WhereClause to be initialized */
-  Parse *pParse,           /* The parsing context */
-  ExprMaskSet *pMaskSet    /* Mapping from table indices to bitmasks */
-){
-  pWC->pParse = pParse;
-  pWC->pMaskSet = pMaskSet;
-  pWC->nTerm = 0;
-  pWC->nSlot = ArraySize(pWC->aStatic);
-  pWC->a = pWC->aStatic;
+        break;
+      case 218: /* expr ::= NOT expr */
+      case 219: /* expr ::= BITNOT expr */ yytestcase(yyruleno==219);
+{spanUnaryPrefix(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
+        break;
+      case 220: /* expr ::= MINUS expr */
+{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UMINUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
+        break;
+      case 221: /* expr ::= PLUS expr */
+{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UPLUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
+        break;
+      case 224: /* expr ::= expr between_op expr AND expr */
+{
+  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy346.pExpr, 0, 0);
+  if( yygotominor.yy346.pExpr ){
+    yygotominor.yy346.pExpr->x.pList = pList;
+  }else{
+    sqlite3ExprListDelete(pParse->db, pList);
+  } 
+  if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
+  yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
+  yygotominor.yy346.zEnd = yymsp[0].minor.yy346.zEnd;
 }
-
-/*
-** Deallocate a WhereClause structure.  The WhereClause structure
-** itself is not freed.  This routine is the inverse of whereClauseInit().
-*/
-static void whereClauseClear(WhereClause *pWC){
-  int i;
-  WhereTerm *a;
-  for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
-    if( a->flags & TERM_DYNAMIC ){
-      sqlite3ExprDelete(a->pExpr);
+        break;
+      case 227: /* expr ::= expr in_op LP exprlist RP */
+{
+    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
+    if( yygotominor.yy346.pExpr ){
+      yygotominor.yy346.pExpr->x.pList = yymsp[-1].minor.yy14;
+      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    }else{
+      sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy14);
     }
+    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
+    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
+    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
-  if( pWC->a!=pWC->aStatic ){
-    sqlite3_free(pWC->a);
-  }
-}
-
-/*
-** Add a new entries to the WhereClause structure.  Increase the allocated
-** space as necessary.
-**
-** If the flags argument includes TERM_DYNAMIC, then responsibility
-** for freeing the expression p is assumed by the WhereClause object.
-**
-** WARNING:  This routine might reallocate the space used to store
-** WhereTerms.  All pointers to WhereTerms should be invalided after
-** calling this routine.  Such pointers may be reinitialized by referencing
-** the pWC->a[] array.
-*/
-static int whereClauseInsert(WhereClause *pWC, Expr *p, int flags){
-  WhereTerm *pTerm;
-  int idx;
-  if( pWC->nTerm>=pWC->nSlot ){
-    WhereTerm *pOld = pWC->a;
-    pWC->a = sqlite3_malloc( sizeof(pWC->a[0])*pWC->nSlot*2 );
-    if( pWC->a==0 ){
-      pWC->pParse->db->mallocFailed = 1;
-      if( flags & TERM_DYNAMIC ){
-        sqlite3ExprDelete(p);
-      }
-      pWC->a = pOld;
-      return 0;
-    }
-    memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
-    if( pOld!=pWC->aStatic ){
-      sqlite3_free(pOld);
+        break;
+      case 228: /* expr ::= LP select RP */
+{
+    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
+    if( yygotominor.yy346.pExpr ){
+      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
+      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    }else{
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
     }
-    pWC->nSlot *= 2;
+    yygotominor.yy346.zStart = yymsp[-2].minor.yy0.z;
+    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
-  pTerm = &pWC->a[idx = pWC->nTerm];
-  pWC->nTerm++;
-  pTerm->pExpr = p;
-  pTerm->flags = flags;
-  pTerm->pWC = pWC;
-  pTerm->iParent = -1;
-  return idx;
-}
-
-/*
-** This routine identifies subexpressions in the WHERE clause where
-** each subexpression is separated by the AND operator or some other
-** operator specified in the op parameter.  The WhereClause structure
-** is filled with pointers to subexpressions.  For example:
-**
-**    WHERE  a=='hello' AND coalesce(b,11)<10 AND (c+12!=d OR c==22)
-**           \________/     \_______________/     \________________/
-**            slot[0]            slot[1]               slot[2]
-**
-** The original WHERE clause in pExpr is unaltered.  All this routine
-** does is make slot[] entries point to substructure within pExpr.
-**
-** In the previous sentence and in the diagram, "slot[]" refers to
-** the WhereClause.a[] array.  This array grows as needed to contain
-** all terms of the WHERE clause.
-*/
-static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
-  if( pExpr==0 ) return;
-  if( pExpr->op!=op ){
-    whereClauseInsert(pWC, pExpr, 0);
-  }else{
-    whereSplit(pWC, pExpr->pLeft, op);
-    whereSplit(pWC, pExpr->pRight, op);
+        break;
+      case 229: /* expr ::= expr in_op LP select RP */
+{
+    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
+    if( yygotominor.yy346.pExpr ){
+      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
+      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    }else{
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+    }
+    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
+    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
+    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
-}
-
-/*
-** Initialize an expression mask set
-*/
-#define initMaskSet(P)  memset(P, 0, sizeof(*P))
-
-/*
-** Return the bitmask for the given cursor number.  Return 0 if
-** iCursor is not in the set.
-*/
-static Bitmask getMask(ExprMaskSet *pMaskSet, int iCursor){
-  int i;
-  for(i=0; i<pMaskSet->n; i++){
-    if( pMaskSet->ix[i]==iCursor ){
-      return ((Bitmask)1)<<i;
+        break;
+      case 230: /* expr ::= expr in_op nm dbnm */
+{
+    SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);
+    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy346.pExpr, 0, 0);
+    if( yygotominor.yy346.pExpr ){
+      yygotominor.yy346.pExpr->x.pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
+      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    }else{
+      sqlite3SrcListDelete(pParse->db, pSrc);
     }
+    if( yymsp[-2].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
+    yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
+    yygotominor.yy346.zEnd = yymsp[0].minor.yy0.z ? &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] : &yymsp[-1].minor.yy0.z[yymsp[-1].minor.yy0.n];
   }
-  return 0;
+        break;
+      case 231: /* expr ::= EXISTS LP select RP */
+{
+    Expr *p = yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
+    if( p ){
+      p->x.pSelect = yymsp[-1].minor.yy3;
+      ExprSetProperty(p, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, p);
+    }else{
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+    }
+    yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
+    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  }
+        break;
+      case 232: /* expr ::= CASE case_operand case_exprlist case_else END */
+{
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy132, yymsp[-1].minor.yy132, 0);
+  if( yygotominor.yy346.pExpr ){
+    yygotominor.yy346.pExpr->x.pList = yymsp[-2].minor.yy14;
+    sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+  }else{
+    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy14);
+  }
+  yygotominor.yy346.zStart = yymsp[-4].minor.yy0.z;
+  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
-
-/*
-** Create a new mask for cursor iCursor.
-**
-** There is one cursor per table in the FROM clause.  The number of
-** tables in the FROM clause is limited by a test early in the
-** sqlite3WhereBegin() routine.  So we know that the pMaskSet->ix[]
-** array will never overflow.
-*/
-static void createMask(ExprMaskSet *pMaskSet, int iCursor){
-  assert( pMaskSet->n < ArraySize(pMaskSet->ix) );
-  pMaskSet->ix[pMaskSet->n++] = iCursor;
+        break;
+      case 233: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, yymsp[-2].minor.yy346.pExpr);
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
 }
-
-/*
-** This routine walks (recursively) an expression tree and generates
-** a bitmask indicating which tables are used in that expression
-** tree.
-**
-** In order for this routine to work, the calling function must have
-** previously invoked sqlite3ExprResolveNames() on the expression.  See
-** the header comment on that routine for additional information.
-** The sqlite3ExprResolveNames() routines looks for column names and
-** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
-** the VDBE cursor number of the table.  This routine just has to
-** translate the cursor numbers into bitmask values and OR all
-** the bitmasks together.
-*/
-static Bitmask exprListTableUsage(ExprMaskSet*, ExprList*);
-static Bitmask exprSelectTableUsage(ExprMaskSet*, Select*);
-static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
-  Bitmask mask = 0;
-  if( p==0 ) return 0;
-  if( p->op==TK_COLUMN ){
-    mask = getMask(pMaskSet, p->iTable);
-    return mask;
+        break;
+      case 234: /* case_exprlist ::= WHEN expr THEN expr */
+{
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
+}
+        break;
+      case 243: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
+{
+  sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy0, &yymsp[-5].minor.yy0, 
+                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy14, yymsp[-9].minor.yy328,
+                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy328);
+}
+        break;
+      case 244: /* uniqueflag ::= UNIQUE */
+      case 298: /* raisetype ::= ABORT */ yytestcase(yyruleno==298);
+{yygotominor.yy328 = OE_Abort;}
+        break;
+      case 245: /* uniqueflag ::= */
+{yygotominor.yy328 = OE_None;}
+        break;
+      case 248: /* idxlist ::= idxlist COMMA nm collate sortorder */
+{
+  Expr *p = 0;
+  if( yymsp[-1].minor.yy0.n>0 ){
+    p = sqlite3Expr(pParse->db, TK_COLUMN, 0);
+    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
   }
-  mask = exprTableUsage(pMaskSet, p->pRight);
-  mask |= exprTableUsage(pMaskSet, p->pLeft);
-  mask |= exprListTableUsage(pMaskSet, p->pList);
-  mask |= exprSelectTableUsage(pMaskSet, p->pSelect);
-  return mask;
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, p);
+  sqlite3ExprListSetName(pParse,yygotominor.yy14,&yymsp[-2].minor.yy0,1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
+  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
 }
-static Bitmask exprListTableUsage(ExprMaskSet *pMaskSet, ExprList *pList){
-  int i;
-  Bitmask mask = 0;
-  if( pList ){
-    for(i=0; i<pList->nExpr; i++){
-      mask |= exprTableUsage(pMaskSet, pList->a[i].pExpr);
-    }
+        break;
+      case 249: /* idxlist ::= nm collate sortorder */
+{
+  Expr *p = 0;
+  if( yymsp[-1].minor.yy0.n>0 ){
+    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
+    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
   }
-  return mask;
+  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, p);
+  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
+  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
 }
-static Bitmask exprSelectTableUsage(ExprMaskSet *pMaskSet, Select *pS){
-  Bitmask mask = 0;
-  while( pS ){
-    mask |= exprListTableUsage(pMaskSet, pS->pEList);
-    mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
-    mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
-    mask |= exprTableUsage(pMaskSet, pS->pWhere);
-    mask |= exprTableUsage(pMaskSet, pS->pHaving);
-    pS = pS->pPrior;
+        break;
+      case 250: /* collate ::= */
+{yygotominor.yy0.z = 0; yygotominor.yy0.n = 0;}
+        break;
+      case 252: /* cmd ::= DROP INDEX ifexists fullname */
+{sqlite3DropIndex(pParse, yymsp[0].minor.yy65, yymsp[-1].minor.yy328);}
+        break;
+      case 253: /* cmd ::= VACUUM */
+      case 254: /* cmd ::= VACUUM nm */ yytestcase(yyruleno==254);
+{sqlite3Vacuum(pParse);}
+        break;
+      case 255: /* cmd ::= PRAGMA nm dbnm */
+{sqlite3Pragma(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0,0);}
+        break;
+      case 256: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
+{sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,0);}
+        break;
+      case 257: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
+{sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,0);}
+        break;
+      case 258: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
+{sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,1);}
+        break;
+      case 259: /* cmd ::= PRAGMA nm dbnm LP minus_num RP */
+{sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,1);}
+        break;
+      case 270: /* cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END */
+{
+  Token all;
+  all.z = yymsp[-3].minor.yy0.z;
+  all.n = (int)(yymsp[0].minor.yy0.z - yymsp[-3].minor.yy0.z) + yymsp[0].minor.yy0.n;
+  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy473, &all);
+}
+        break;
+      case 271: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
+{
+  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy328, yymsp[-4].minor.yy378.a, yymsp[-4].minor.yy378.b, yymsp[-2].minor.yy65, yymsp[0].minor.yy132, yymsp[-10].minor.yy328, yymsp[-8].minor.yy328);
+  yygotominor.yy0 = (yymsp[-6].minor.yy0.n==0?yymsp[-7].minor.yy0:yymsp[-6].minor.yy0);
+}
+        break;
+      case 272: /* trigger_time ::= BEFORE */
+      case 275: /* trigger_time ::= */ yytestcase(yyruleno==275);
+{ yygotominor.yy328 = TK_BEFORE; }
+        break;
+      case 273: /* trigger_time ::= AFTER */
+{ yygotominor.yy328 = TK_AFTER;  }
+        break;
+      case 274: /* trigger_time ::= INSTEAD OF */
+{ yygotominor.yy328 = TK_INSTEAD;}
+        break;
+      case 276: /* trigger_event ::= DELETE|INSERT */
+      case 277: /* trigger_event ::= UPDATE */ yytestcase(yyruleno==277);
+{yygotominor.yy378.a = yymsp[0].major; yygotominor.yy378.b = 0;}
+        break;
+      case 278: /* trigger_event ::= UPDATE OF inscollist */
+{yygotominor.yy378.a = TK_UPDATE; yygotominor.yy378.b = yymsp[0].minor.yy408;}
+        break;
+      case 281: /* when_clause ::= */
+      case 303: /* key_opt ::= */ yytestcase(yyruleno==303);
+{ yygotominor.yy132 = 0; }
+        break;
+      case 282: /* when_clause ::= WHEN expr */
+      case 304: /* key_opt ::= KEY expr */ yytestcase(yyruleno==304);
+{ yygotominor.yy132 = yymsp[0].minor.yy346.pExpr; }
+        break;
+      case 283: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
+{
+  assert( yymsp[-2].minor.yy473!=0 );
+  yymsp[-2].minor.yy473->pLast->pNext = yymsp[-1].minor.yy473;
+  yymsp[-2].minor.yy473->pLast = yymsp[-1].minor.yy473;
+  yygotominor.yy473 = yymsp[-2].minor.yy473;
+}
+        break;
+      case 284: /* trigger_cmd_list ::= trigger_cmd SEMI */
+{ 
+  assert( yymsp[-1].minor.yy473!=0 );
+  yymsp[-1].minor.yy473->pLast = yymsp[-1].minor.yy473;
+  yygotominor.yy473 = yymsp[-1].minor.yy473;
+}
+        break;
+      case 286: /* trnm ::= nm DOT nm */
+{
+  yygotominor.yy0 = yymsp[0].minor.yy0;
+  sqlite3ErrorMsg(pParse, 
+        "qualified table names are not allowed on INSERT, UPDATE, and DELETE "
+        "statements within triggers");
+}
+        break;
+      case 288: /* tridxby ::= INDEXED BY nm */
+{
+  sqlite3ErrorMsg(pParse,
+        "the INDEXED BY clause is not allowed on UPDATE or DELETE statements "
+        "within triggers");
+}
+        break;
+      case 289: /* tridxby ::= NOT INDEXED */
+{
+  sqlite3ErrorMsg(pParse,
+        "the NOT INDEXED clause is not allowed on UPDATE or DELETE statements "
+        "within triggers");
+}
+        break;
+      case 290: /* trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt */
+{ yygotominor.yy473 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-4].minor.yy0, yymsp[-1].minor.yy14, yymsp[0].minor.yy132, yymsp[-5].minor.yy186); }
+        break;
+      case 291: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP */
+{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy408, yymsp[-1].minor.yy14, 0, yymsp[-7].minor.yy186);}
+        break;
+      case 292: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select */
+{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy408, 0, yymsp[0].minor.yy3, yymsp[-4].minor.yy186);}
+        break;
+      case 293: /* trigger_cmd ::= DELETE FROM trnm tridxby where_opt */
+{yygotominor.yy473 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[0].minor.yy132);}
+        break;
+      case 294: /* trigger_cmd ::= select */
+{yygotominor.yy473 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy3); }
+        break;
+      case 295: /* expr ::= RAISE LP IGNORE RP */
+{
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
+  if( yygotominor.yy346.pExpr ){
+    yygotominor.yy346.pExpr->affinity = OE_Ignore;
   }
-  return mask;
+  yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
+  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
-
-/*
-** Return TRUE if the given operator is one of the operators that is
-** allowed for an indexable WHERE clause term.  The allowed operators are
-** "=", "<", ">", "<=", ">=", and "IN".
-*/
-static int allowedOp(int op){
-  assert( TK_GT>TK_EQ && TK_GT<TK_GE );
-  assert( TK_LT>TK_EQ && TK_LT<TK_GE );
-  assert( TK_LE>TK_EQ && TK_LE<TK_GE );
-  assert( TK_GE==TK_EQ+4 );
-  return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
+        break;
+      case 296: /* expr ::= RAISE LP raisetype COMMA nm RP */
+{
+  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
+  if( yygotominor.yy346.pExpr ) {
+    yygotominor.yy346.pExpr->affinity = (char)yymsp[-3].minor.yy328;
+  }
+  yygotominor.yy346.zStart = yymsp[-5].minor.yy0.z;
+  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
-
-/*
-** Swap two objects of type T.
-*/
-#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
-
-/*
-** Commute a comparision operator.  Expressions of the form "X op Y"
-** are converted into "Y op X".
-**
-** If a collation sequence is associated with either the left or right
-** side of the comparison, it remains associated with the same side after
-** the commutation. So "Y collate NOCASE op X" becomes 
-** "X collate NOCASE op Y". This is because any collation sequence on
-** the left hand side of a comparison overrides any collation sequence 
-** attached to the right. For the same reason the EP_ExpCollate flag
-** is not commuted.
-*/
-static void exprCommute(Expr *pExpr){
-  u16 expRight = (pExpr->pRight->flags & EP_ExpCollate);
-  u16 expLeft = (pExpr->pLeft->flags & EP_ExpCollate);
-  assert( allowedOp(pExpr->op) && pExpr->op!=TK_IN );
-  SWAP(CollSeq*,pExpr->pRight->pColl,pExpr->pLeft->pColl);
-  pExpr->pRight->flags = (pExpr->pRight->flags & ~EP_ExpCollate) | expLeft;
-  pExpr->pLeft->flags = (pExpr->pLeft->flags & ~EP_ExpCollate) | expRight;
-  SWAP(Expr*,pExpr->pRight,pExpr->pLeft);
-  if( pExpr->op>=TK_GT ){
-    assert( TK_LT==TK_GT+2 );
-    assert( TK_GE==TK_LE+2 );
-    assert( TK_GT>TK_EQ );
-    assert( TK_GT<TK_LE );
-    assert( pExpr->op>=TK_GT && pExpr->op<=TK_GE );
-    pExpr->op = ((pExpr->op-TK_GT)^2)+TK_GT;
+        break;
+      case 297: /* raisetype ::= ROLLBACK */
+{yygotominor.yy328 = OE_Rollback;}
+        break;
+      case 299: /* raisetype ::= FAIL */
+{yygotominor.yy328 = OE_Fail;}
+        break;
+      case 300: /* cmd ::= DROP TRIGGER ifexists fullname */
+{
+  sqlite3DropTrigger(pParse,yymsp[0].minor.yy65,yymsp[-1].minor.yy328);
+}
+        break;
+      case 301: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
+{
+  sqlite3Attach(pParse, yymsp[-3].minor.yy346.pExpr, yymsp[-1].minor.yy346.pExpr, yymsp[0].minor.yy132);
+}
+        break;
+      case 302: /* cmd ::= DETACH database_kw_opt expr */
+{
+  sqlite3Detach(pParse, yymsp[0].minor.yy346.pExpr);
+}
+        break;
+      case 307: /* cmd ::= REINDEX */
+{sqlite3Reindex(pParse, 0, 0);}
+        break;
+      case 308: /* cmd ::= REINDEX nm dbnm */
+{sqlite3Reindex(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
+        break;
+      case 309: /* cmd ::= ANALYZE */
+{sqlite3Analyze(pParse, 0, 0);}
+        break;
+      case 310: /* cmd ::= ANALYZE nm dbnm */
+{sqlite3Analyze(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
+        break;
+      case 311: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
+{
+  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy65,&yymsp[0].minor.yy0);
+}
+        break;
+      case 312: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
+{
+  sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy0);
+}
+        break;
+      case 313: /* add_column_fullname ::= fullname */
+{
+  pParse->db->lookaside.bEnabled = 0;
+  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy65);
+}
+        break;
+      case 316: /* cmd ::= create_vtab */
+{sqlite3VtabFinishParse(pParse,0);}
+        break;
+      case 317: /* cmd ::= create_vtab LP vtabarglist RP */
+{sqlite3VtabFinishParse(pParse,&yymsp[0].minor.yy0);}
+        break;
+      case 318: /* create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm */
+{
+    sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, &yymsp[0].minor.yy0);
+}
+        break;
+      case 321: /* vtabarg ::= */
+{sqlite3VtabArgInit(pParse);}
+        break;
+      case 323: /* vtabargtoken ::= ANY */
+      case 324: /* vtabargtoken ::= lp anylist RP */ yytestcase(yyruleno==324);
+      case 325: /* lp ::= LP */ yytestcase(yyruleno==325);
+{sqlite3VtabArgExtend(pParse,&yymsp[0].minor.yy0);}
+        break;
+      default:
+      /* (0) input ::= cmdlist */ yytestcase(yyruleno==0);
+      /* (1) cmdlist ::= cmdlist ecmd */ yytestcase(yyruleno==1);
+      /* (2) cmdlist ::= ecmd */ yytestcase(yyruleno==2);
+      /* (3) ecmd ::= SEMI */ yytestcase(yyruleno==3);
+      /* (4) ecmd ::= explain cmdx SEMI */ yytestcase(yyruleno==4);
+      /* (10) trans_opt ::= */ yytestcase(yyruleno==10);
+      /* (11) trans_opt ::= TRANSACTION */ yytestcase(yyruleno==11);
+      /* (12) trans_opt ::= TRANSACTION nm */ yytestcase(yyruleno==12);
+      /* (20) savepoint_opt ::= SAVEPOINT */ yytestcase(yyruleno==20);
+      /* (21) savepoint_opt ::= */ yytestcase(yyruleno==21);
+      /* (25) cmd ::= create_table create_table_args */ yytestcase(yyruleno==25);
+      /* (34) columnlist ::= columnlist COMMA column */ yytestcase(yyruleno==34);
+      /* (35) columnlist ::= column */ yytestcase(yyruleno==35);
+      /* (44) type ::= */ yytestcase(yyruleno==44);
+      /* (51) signed ::= plus_num */ yytestcase(yyruleno==51);
+      /* (52) signed ::= minus_num */ yytestcase(yyruleno==52);
+      /* (53) carglist ::= carglist carg */ yytestcase(yyruleno==53);
+      /* (54) carglist ::= */ yytestcase(yyruleno==54);
+      /* (55) carg ::= CONSTRAINT nm ccons */ yytestcase(yyruleno==55);
+      /* (56) carg ::= ccons */ yytestcase(yyruleno==56);
+      /* (62) ccons ::= NULL onconf */ yytestcase(yyruleno==62);
+      /* (89) conslist ::= conslist COMMA tcons */ yytestcase(yyruleno==89);
+      /* (90) conslist ::= conslist tcons */ yytestcase(yyruleno==90);
+      /* (91) conslist ::= tcons */ yytestcase(yyruleno==91);
+      /* (92) tcons ::= CONSTRAINT nm */ yytestcase(yyruleno==92);
+      /* (268) plus_opt ::= PLUS */ yytestcase(yyruleno==268);
+      /* (269) plus_opt ::= */ yytestcase(yyruleno==269);
+      /* (279) foreach_clause ::= */ yytestcase(yyruleno==279);
+      /* (280) foreach_clause ::= FOR EACH ROW */ yytestcase(yyruleno==280);
+      /* (287) tridxby ::= */ yytestcase(yyruleno==287);
+      /* (305) database_kw_opt ::= DATABASE */ yytestcase(yyruleno==305);
+      /* (306) database_kw_opt ::= */ yytestcase(yyruleno==306);
+      /* (314) kwcolumn_opt ::= */ yytestcase(yyruleno==314);
+      /* (315) kwcolumn_opt ::= COLUMNKW */ yytestcase(yyruleno==315);
+      /* (319) vtabarglist ::= vtabarg */ yytestcase(yyruleno==319);
+      /* (320) vtabarglist ::= vtabarglist COMMA vtabarg */ yytestcase(yyruleno==320);
+      /* (322) vtabarg ::= vtabarg vtabargtoken */ yytestcase(yyruleno==322);
+      /* (326) anylist ::= */ yytestcase(yyruleno==326);
+      /* (327) anylist ::= anylist LP anylist RP */ yytestcase(yyruleno==327);
+      /* (328) anylist ::= anylist ANY */ yytestcase(yyruleno==328);
+        break;
+  };
+  yygoto = yyRuleInfo[yyruleno].lhs;
+  yysize = yyRuleInfo[yyruleno].nrhs;
+  yypParser->yyidx -= yysize;
+  yyact = yy_find_reduce_action(yymsp[-yysize].stateno,(YYCODETYPE)yygoto);
+  if( yyact < YYNSTATE ){
+#ifdef NDEBUG
+    /* If we are not debugging and the reduce action popped at least
+    ** one element off the stack, then we can push the new element back
+    ** onto the stack here, and skip the stack overflow test in yy_shift().
+    ** That gives a significant speed improvement. */
+    if( yysize ){
+      yypParser->yyidx++;
+      yymsp -= yysize-1;
+      yymsp->stateno = (YYACTIONTYPE)yyact;
+      yymsp->major = (YYCODETYPE)yygoto;
+      yymsp->minor = yygotominor;
+    }else
+#endif
+    {
+      yy_shift(yypParser,yyact,yygoto,&yygotominor);
+    }
+  }else{
+    assert( yyact == YYNSTATE + YYNRULE + 1 );
+    yy_accept(yypParser);
   }
 }
 
 /*
-** Translate from TK_xx operator to WO_xx bitmask.
+** The following code executes when the parse fails
 */
-static int operatorMask(int op){
-  int c;
-  assert( allowedOp(op) );
-  if( op==TK_IN ){
-    c = WO_IN;
-  }else if( op==TK_ISNULL ){
-    c = WO_ISNULL;
-  }else{
-    c = WO_EQ<<(op-TK_EQ);
+#ifndef YYNOERRORRECOVERY
+static void yy_parse_failed(
+  yyParser *yypParser           /* The parser */
+){
+  sqlite3ParserARG_FETCH;
+#ifndef NDEBUG
+  if( yyTraceFILE ){
+    fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt);
   }
-  assert( op!=TK_ISNULL || c==WO_ISNULL );
-  assert( op!=TK_IN || c==WO_IN );
-  assert( op!=TK_EQ || c==WO_EQ );
-  assert( op!=TK_LT || c==WO_LT );
-  assert( op!=TK_LE || c==WO_LE );
-  assert( op!=TK_GT || c==WO_GT );
-  assert( op!=TK_GE || c==WO_GE );
-  return c;
+#endif
+  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
+  /* Here code is inserted which will be executed whenever the
+  ** parser fails */
+  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
 }
+#endif /* YYNOERRORRECOVERY */
 
 /*
-** Search for a term in the WHERE clause that is of the form "X <op> <expr>"
-** where X is a reference to the iColumn of table iCur and <op> is one of
-** the WO_xx operator codes specified by the op parameter.
-** Return a pointer to the term.  Return 0 if not found.
+** The following code executes when a syntax error first occurs.
 */
-static WhereTerm *findTerm(
-  WhereClause *pWC,     /* The WHERE clause to be searched */
-  int iCur,             /* Cursor number of LHS */
-  int iColumn,          /* Column number of LHS */
-  Bitmask notReady,     /* RHS must not overlap with this mask */
-  u16 op,               /* Mask of WO_xx values describing operator */
-  Index *pIdx           /* Must be compatible with this index, if not NULL */
+static void yy_syntax_error(
+  yyParser *yypParser,           /* The parser */
+  int yymajor,                   /* The major type of the error token */
+  YYMINORTYPE yyminor            /* The minor type of the error token */
 ){
-  WhereTerm *pTerm;
-  int k;
-  for(pTerm=pWC->a, k=pWC->nTerm; k; k--, pTerm++){
-    if( pTerm->leftCursor==iCur
-       && (pTerm->prereqRight & notReady)==0
-       && pTerm->leftColumn==iColumn
-       && (pTerm->eOperator & op)!=0
-    ){
-      if( iCur>=0 && pIdx && pTerm->eOperator!=WO_ISNULL ){
-        Expr *pX = pTerm->pExpr;
-        CollSeq *pColl;
-        char idxaff;
-        int j;
-        Parse *pParse = pWC->pParse;
-
-        idxaff = pIdx->pTable->aCol[iColumn].affinity;
-        if( !sqlite3IndexAffinityOk(pX, idxaff) ) continue;
-
-        /* Figure out the collation sequence required from an index for
-        ** it to be useful for optimising expression pX. Store this
-        ** value in variable pColl.
-        */
-        assert(pX->pLeft);
-        pColl = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
-        if( !pColl ){
-          pColl = pParse->db->pDfltColl;
-        }
+  sqlite3ParserARG_FETCH;
+#define TOKEN (yyminor.yy0)
 
-        for(j=0; j<pIdx->nColumn && pIdx->aiColumn[j]!=iColumn; j++){}
-        assert( j<pIdx->nColumn );
-        if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
-      }
-      return pTerm;
-    }
-  }
-  return 0;
+  UNUSED_PARAMETER(yymajor);  /* Silence some compiler warnings */
+  assert( TOKEN.z[0] );  /* The tokenizer always gives us a token */
+  sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &TOKEN);
+  pParse->parseError = 1;
+  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
 }
 
-/* Forward reference */
-static void exprAnalyze(SrcList*, WhereClause*, int);
-
 /*
-** Call exprAnalyze on all terms in a WHERE clause.  
-**
-**
+** The following is executed when the parser accepts
 */
-static void exprAnalyzeAll(
-  SrcList *pTabList,       /* the FROM clause */
-  WhereClause *pWC         /* the WHERE clause to be analyzed */
+static void yy_accept(
+  yyParser *yypParser           /* The parser */
 ){
-  int i;
-  for(i=pWC->nTerm-1; i>=0; i--){
-    exprAnalyze(pTabList, pWC, i);
+  sqlite3ParserARG_FETCH;
+#ifndef NDEBUG
+  if( yyTraceFILE ){
+    fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt);
   }
+#endif
+  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
+  /* Here code is inserted which will be executed whenever the
+  ** parser accepts */
+  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
 }
 
-#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
-/*
-** Check to see if the given expression is a LIKE or GLOB operator that
-** can be optimized using inequality constraints.  Return TRUE if it is
-** so and false if not.
+/* The main parser program.
+** The first argument is a pointer to a structure obtained from
+** "sqlite3ParserAlloc" which describes the current state of the parser.
+** The second argument is the major token number.  The third is
+** the minor token.  The fourth optional argument is whatever the
+** user wants (and specified in the grammar) and is available for
+** use by the action routines.
 **
-** In order for the operator to be optimizible, the RHS must be a string
-** literal that does not begin with a wildcard.  
+** Inputs:
+** <ul>
+** <li> A pointer to the parser (an opaque structure.)
+** <li> The major token number.
+** <li> The minor token number.
+** <li> An option argument of a grammar-specified type.
+** </ul>
+**
+** Outputs:
+** None.
 */
-static int isLikeOrGlob(
-  sqlite3 *db,      /* The database */
-  Expr *pExpr,      /* Test this expression */
-  int *pnPattern,   /* Number of non-wildcard prefix characters */
-  int *pisComplete, /* True if the only wildcard is % in the last character */
-  int *pnoCase      /* True if uppercase is equivalent to lowercase */
+SQLITE_PRIVATE void sqlite3Parser(
+  void *yyp,                   /* The parser */
+  int yymajor,                 /* The major token code number */
+  sqlite3ParserTOKENTYPE yyminor       /* The value for the token */
+  sqlite3ParserARG_PDECL               /* Optional %extra_argument parameter */
 ){
-  const char *z;
-  Expr *pRight, *pLeft;
-  ExprList *pList;
-  int c, cnt;
-  char wc[3];
-  CollSeq *pColl;
+  YYMINORTYPE yyminorunion;
+  int yyact;            /* The parser action. */
+  int yyendofinput;     /* True if we are at the end of input */
+#ifdef YYERRORSYMBOL
+  int yyerrorhit = 0;   /* True if yymajor has invoked an error */
+#endif
+  yyParser *yypParser;  /* The parser */
 
-  if( !sqlite3IsLikeFunction(db, pExpr, pnoCase, wc) ){
-    return 0;
+  /* (re)initialize the parser, if necessary */
+  yypParser = (yyParser*)yyp;
+  if( yypParser->yyidx<0 ){
+#if YYSTACKDEPTH<=0
+    if( yypParser->yystksz <=0 ){
+      /*memset(&yyminorunion, 0, sizeof(yyminorunion));*/
+      yyminorunion = yyzerominor;
+      yyStackOverflow(yypParser, &yyminorunion);
+      return;
+    }
+#endif
+    yypParser->yyidx = 0;
+    yypParser->yyerrcnt = -1;
+    yypParser->yystack[0].stateno = 0;
+    yypParser->yystack[0].major = 0;
   }
-#ifdef SQLITE_EBCDIC
-  if( *pnoCase ) return 0;
+  yyminorunion.yy0 = yyminor;
+  yyendofinput = (yymajor==0);
+  sqlite3ParserARG_STORE;
+
+#ifndef NDEBUG
+  if( yyTraceFILE ){
+    fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]);
+  }
+#endif
+
+  do{
+    yyact = yy_find_shift_action(yypParser,(YYCODETYPE)yymajor);
+    if( yyact<YYNSTATE ){
+      assert( !yyendofinput );  /* Impossible to shift the $ token */
+      yy_shift(yypParser,yyact,yymajor,&yyminorunion);
+      yypParser->yyerrcnt--;
+      yymajor = YYNOCODE;
+    }else if( yyact < YYNSTATE + YYNRULE ){
+      yy_reduce(yypParser,yyact-YYNSTATE);
+    }else{
+      assert( yyact == YY_ERROR_ACTION );
+#ifdef YYERRORSYMBOL
+      int yymx;
+#endif
+#ifndef NDEBUG
+      if( yyTraceFILE ){
+        fprintf(yyTraceFILE,"%sSyntax Error!\n",yyTracePrompt);
+      }
+#endif
+#ifdef YYERRORSYMBOL
+      /* A syntax error has occurred.
+      ** The response to an error depends upon whether or not the
+      ** grammar defines an error token "ERROR".  
+      **
+      ** This is what we do if the grammar does define ERROR:
+      **
+      **  * Call the %syntax_error function.
+      **
+      **  * Begin popping the stack until we enter a state where
+      **    it is legal to shift the error symbol, then shift
+      **    the error symbol.
+      **
+      **  * Set the error count to three.
+      **
+      **  * Begin accepting and shifting new tokens.  No new error
+      **    processing will occur until three tokens have been
+      **    shifted successfully.
+      **
+      */
+      if( yypParser->yyerrcnt<0 ){
+        yy_syntax_error(yypParser,yymajor,yyminorunion);
+      }
+      yymx = yypParser->yystack[yypParser->yyidx].major;
+      if( yymx==YYERRORSYMBOL || yyerrorhit ){
+#ifndef NDEBUG
+        if( yyTraceFILE ){
+          fprintf(yyTraceFILE,"%sDiscard input token %s\n",
+             yyTracePrompt,yyTokenName[yymajor]);
+        }
+#endif
+        yy_destructor(yypParser, (YYCODETYPE)yymajor,&yyminorunion);
+        yymajor = YYNOCODE;
+      }else{
+         while(
+          yypParser->yyidx >= 0 &&
+          yymx != YYERRORSYMBOL &&
+          (yyact = yy_find_reduce_action(
+                        yypParser->yystack[yypParser->yyidx].stateno,
+                        YYERRORSYMBOL)) >= YYNSTATE
+        ){
+          yy_pop_parser_stack(yypParser);
+        }
+        if( yypParser->yyidx < 0 || yymajor==0 ){
+          yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
+          yy_parse_failed(yypParser);
+          yymajor = YYNOCODE;
+        }else if( yymx!=YYERRORSYMBOL ){
+          YYMINORTYPE u2;
+          u2.YYERRSYMDT = 0;
+          yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2);
+        }
+      }
+      yypParser->yyerrcnt = 3;
+      yyerrorhit = 1;
+#elif defined(YYNOERRORRECOVERY)
+      /* If the YYNOERRORRECOVERY macro is defined, then do not attempt to
+      ** do any kind of error recovery.  Instead, simply invoke the syntax
+      ** error routine and continue going as if nothing had happened.
+      **
+      ** Applications can set this macro (for example inside %include) if
+      ** they intend to abandon the parse upon the first syntax error seen.
+      */
+      yy_syntax_error(yypParser,yymajor,yyminorunion);
+      yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
+      yymajor = YYNOCODE;
+      
+#else  /* YYERRORSYMBOL is not defined */
+      /* This is what we do if the grammar does not define ERROR:
+      **
+      **  * Report an error message, and throw away the input token.
+      **
+      **  * If the input token is $, then fail the parse.
+      **
+      ** As before, subsequent error messages are suppressed until
+      ** three input tokens have been successfully shifted.
+      */
+      if( yypParser->yyerrcnt<=0 ){
+        yy_syntax_error(yypParser,yymajor,yyminorunion);
+      }
+      yypParser->yyerrcnt = 3;
+      yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
+      if( yyendofinput ){
+        yy_parse_failed(yypParser);
+      }
+      yymajor = YYNOCODE;
 #endif
-  pList = pExpr->pList;
-  pRight = pList->a[0].pExpr;
-  if( pRight->op!=TK_STRING
-   && (pRight->op!=TK_REGISTER || pRight->iColumn!=TK_STRING) ){
-    return 0;
-  }
-  pLeft = pList->a[1].pExpr;
-  if( pLeft->op!=TK_COLUMN ){
-    return 0;
-  }
-  pColl = pLeft->pColl;
-  assert( pColl!=0 || pLeft->iColumn==-1 );
-  if( pColl==0 ){
-    /* No collation is defined for the ROWID.  Use the default. */
-    pColl = db->pDfltColl;
-  }
-  if( (pColl->type!=SQLITE_COLL_BINARY || *pnoCase) &&
-      (pColl->type!=SQLITE_COLL_NOCASE || !*pnoCase) ){
-    return 0;
-  }
-  sqlite3DequoteExpr(db, pRight);
-  z = (char *)pRight->token.z;
-  cnt = 0;
-  if( z ){
-    while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){ cnt++; }
-  }
-  if( cnt==0 || 255==(u8)z[cnt] ){
-    return 0;
-  }
-  *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
-  *pnPattern = cnt;
-  return 1;
+    }
+  }while( yymajor!=YYNOCODE && yypParser->yyidx>=0 );
+  return;
 }
-#endif /* SQLITE_OMIT_LIKE_OPTIMIZATION */
 
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
+/************** End of parse.c ***********************************************/
+/************** Begin file tokenize.c ****************************************/
 /*
-** Check to see if the given expression is of the form
+** 2001 September 15
 **
-**         column MATCH expr
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** If it is then return TRUE.  If not, return FALSE.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** An tokenizer for SQL
+**
+** This file contains C code that splits an SQL input string up into
+** individual tokens and sends those tokens one-by-one over to the
+** parser for analysis.
+**
+** $Id: tokenize.c,v 1.163 2009/07/03 22:54:37 drh Exp $
 */
-static int isMatchOfColumn(
-  Expr *pExpr      /* Test this expression */
-){
-  ExprList *pList;
-
-  if( pExpr->op!=TK_FUNCTION ){
-    return 0;
-  }
-  if( pExpr->token.n!=5 ||
-       sqlite3StrNICmp((const char*)pExpr->token.z,"match",5)!=0 ){
-    return 0;
-  }
-  pList = pExpr->pList;
-  if( pList->nExpr!=2 ){
-    return 0;
-  }
-  if( pList->a[1].pExpr->op != TK_COLUMN ){
-    return 0;
-  }
-  return 1;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
 /*
-** If the pBase expression originated in the ON or USING clause of
-** a join, then transfer the appropriate markings over to derived.
+** The charMap() macro maps alphabetic characters into their
+** lower-case ASCII equivalent.  On ASCII machines, this is just
+** an upper-to-lower case map.  On EBCDIC machines we also need
+** to adjust the encoding.  Only alphabetic characters and underscores
+** need to be translated.
 */
-static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
-  pDerived->flags |= pBase->flags & EP_FromJoin;
-  pDerived->iRightJoinTable = pBase->iRightJoinTable;
-}
+#ifdef SQLITE_ASCII
+# define charMap(X) sqlite3UpperToLower[(unsigned char)X]
+#endif
+#ifdef SQLITE_EBCDIC
+# define charMap(X) ebcdicToAscii[(unsigned char)X]
+const unsigned char ebcdicToAscii[] = {
+/* 0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 0x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 1x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 2x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 3x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 4x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 5x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 95,  0,  0,  /* 6x */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 7x */
+   0, 97, 98, 99,100,101,102,103,104,105,  0,  0,  0,  0,  0,  0,  /* 8x */
+   0,106,107,108,109,110,111,112,113,114,  0,  0,  0,  0,  0,  0,  /* 9x */
+   0,  0,115,116,117,118,119,120,121,122,  0,  0,  0,  0,  0,  0,  /* Ax */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* Bx */
+   0, 97, 98, 99,100,101,102,103,104,105,  0,  0,  0,  0,  0,  0,  /* Cx */
+   0,106,107,108,109,110,111,112,113,114,  0,  0,  0,  0,  0,  0,  /* Dx */
+   0,  0,115,116,117,118,119,120,121,122,  0,  0,  0,  0,  0,  0,  /* Ex */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* Fx */
+};
+#endif
 
-#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
 /*
-** Return TRUE if the given term of an OR clause can be converted
-** into an IN clause.  The iCursor and iColumn define the left-hand
-** side of the IN clause.
-**
-** The context is that we have multiple OR-connected equality terms
-** like this:
-**
-**           a=<expr1> OR  a=<expr2> OR b=<expr3>  OR ...
+** The sqlite3KeywordCode function looks up an identifier to determine if
+** it is a keyword.  If it is a keyword, the token code of that keyword is 
+** returned.  If the input is not a keyword, TK_ID is returned.
 **
-** The pOrTerm input to this routine corresponds to a single term of
-** this OR clause.  In order for the term to be a condidate for
-** conversion to an IN operator, the following must be true:
+** The implementation of this routine was generated by a program,
+** mkkeywordhash.h, located in the tool subdirectory of the distribution.
+** The output of the mkkeywordhash.c program is written into a file
+** named keywordhash.h and then included into this source file by
+** the #include below.
+*/
+/************** Include keywordhash.h in the middle of tokenize.c ************/
+/************** Begin file keywordhash.h *************************************/
+/***** This file contains automatically generated code ******
 **
-**     *  The left-hand side of the term must be the column which
-**        is identified by iCursor and iColumn.
+** The code in this file has been automatically generated by
 **
-**     *  If the right-hand side is also a column, then the affinities
-**        of both right and left sides must be such that no type
-**        conversions are required on the right.  (Ticket #2249)
+**     $Header: /home/drh/sqlite/trans/cvs/sqlite/sqlite/tool/mkkeywordhash.c,v 1.38 2009/06/09 14:27:41 drh Exp $
 **
-** If both of these conditions are true, then return true.  Otherwise
-** return false.
+** The code in this file implements a function that determines whether
+** or not a given identifier is really an SQL keyword.  The same thing
+** might be implemented more directly using a hand-written hash table.
+** But by using this automatically generated code, the size of the code
+** is substantially reduced.  This is important for embedded applications
+** on platforms with limited memory.
 */
-static int orTermIsOptCandidate(WhereTerm *pOrTerm, int iCursor, int iColumn){
-  int affLeft, affRight;
-  assert( pOrTerm->eOperator==WO_EQ );
-  if( pOrTerm->leftCursor!=iCursor ){
-    return 0;
-  }
-  if( pOrTerm->leftColumn!=iColumn ){
-    return 0;
-  }
-  affRight = sqlite3ExprAffinity(pOrTerm->pExpr->pRight);
-  if( affRight==0 ){
-    return 1;
-  }
-  affLeft = sqlite3ExprAffinity(pOrTerm->pExpr->pLeft);
-  if( affRight!=affLeft ){
-    return 0;
+/* Hash score: 175 */
+static int keywordCode(const char *z, int n){
+  /* zText[] encodes 811 bytes of keywords in 541 bytes */
+  /*   REINDEXEDESCAPEACHECKEYBEFOREIGNOREGEXPLAINSTEADDATABASELECT       */
+  /*   ABLEFTHENDEFERRABLELSEXCEPTRANSACTIONATURALTERAISEXCLUSIVE         */
+  /*   XISTSAVEPOINTERSECTRIGGEREFERENCESCONSTRAINTOFFSETEMPORARY         */
+  /*   UNIQUERYATTACHAVINGROUPDATEBEGINNERELEASEBETWEENOTNULLIKE          */
+  /*   CASCADELETECASECOLLATECREATECURRENT_DATEDETACHIMMEDIATEJOIN        */
+  /*   SERTMATCHPLANALYZEPRAGMABORTVALUESVIRTUALIMITWHENWHERENAME         */
+  /*   AFTEREPLACEANDEFAULTAUTOINCREMENTCASTCOLUMNCOMMITCONFLICTCROSS     */
+  /*   CURRENT_TIMESTAMPRIMARYDEFERREDISTINCTDROPFAILFROMFULLGLOBYIF      */
+  /*   ISNULLORDERESTRICTOUTERIGHTROLLBACKROWUNIONUSINGVACUUMVIEW         */
+  /*   INITIALLY                                                          */
+  static const char zText[540] = {
+    'R','E','I','N','D','E','X','E','D','E','S','C','A','P','E','A','C','H',
+    'E','C','K','E','Y','B','E','F','O','R','E','I','G','N','O','R','E','G',
+    'E','X','P','L','A','I','N','S','T','E','A','D','D','A','T','A','B','A',
+    'S','E','L','E','C','T','A','B','L','E','F','T','H','E','N','D','E','F',
+    'E','R','R','A','B','L','E','L','S','E','X','C','E','P','T','R','A','N',
+    'S','A','C','T','I','O','N','A','T','U','R','A','L','T','E','R','A','I',
+    'S','E','X','C','L','U','S','I','V','E','X','I','S','T','S','A','V','E',
+    'P','O','I','N','T','E','R','S','E','C','T','R','I','G','G','E','R','E',
+    'F','E','R','E','N','C','E','S','C','O','N','S','T','R','A','I','N','T',
+    'O','F','F','S','E','T','E','M','P','O','R','A','R','Y','U','N','I','Q',
+    'U','E','R','Y','A','T','T','A','C','H','A','V','I','N','G','R','O','U',
+    'P','D','A','T','E','B','E','G','I','N','N','E','R','E','L','E','A','S',
+    'E','B','E','T','W','E','E','N','O','T','N','U','L','L','I','K','E','C',
+    'A','S','C','A','D','E','L','E','T','E','C','A','S','E','C','O','L','L',
+    'A','T','E','C','R','E','A','T','E','C','U','R','R','E','N','T','_','D',
+    'A','T','E','D','E','T','A','C','H','I','M','M','E','D','I','A','T','E',
+    'J','O','I','N','S','E','R','T','M','A','T','C','H','P','L','A','N','A',
+    'L','Y','Z','E','P','R','A','G','M','A','B','O','R','T','V','A','L','U',
+    'E','S','V','I','R','T','U','A','L','I','M','I','T','W','H','E','N','W',
+    'H','E','R','E','N','A','M','E','A','F','T','E','R','E','P','L','A','C',
+    'E','A','N','D','E','F','A','U','L','T','A','U','T','O','I','N','C','R',
+    'E','M','E','N','T','C','A','S','T','C','O','L','U','M','N','C','O','M',
+    'M','I','T','C','O','N','F','L','I','C','T','C','R','O','S','S','C','U',
+    'R','R','E','N','T','_','T','I','M','E','S','T','A','M','P','R','I','M',
+    'A','R','Y','D','E','F','E','R','R','E','D','I','S','T','I','N','C','T',
+    'D','R','O','P','F','A','I','L','F','R','O','M','F','U','L','L','G','L',
+    'O','B','Y','I','F','I','S','N','U','L','L','O','R','D','E','R','E','S',
+    'T','R','I','C','T','O','U','T','E','R','I','G','H','T','R','O','L','L',
+    'B','A','C','K','R','O','W','U','N','I','O','N','U','S','I','N','G','V',
+    'A','C','U','U','M','V','I','E','W','I','N','I','T','I','A','L','L','Y',
+  };
+  static const unsigned char aHash[127] = {
+      72, 101, 114,  70,   0,  44,   0,   0,  78,   0,  73,   0,   0,
+      42,  12,  74,  15,   0, 113,  81,  50, 108,   0,  19,   0,   0,
+     118,   0, 116, 111,   0,  22,  89,   0,   9,   0,   0,  66,  67,
+       0,  65,   6,   0,  48,  86,  98,   0, 115,  97,   0,   0,  45,
+       0,  99,  24,   0,  17,   0, 119,  49,  23,   0,   5, 106,  25,
+      92,   0,   0, 121, 102,  56, 120,  53,  28,  51,   0,  87,   0,
+      96,  26,   0,  95,   0,   0,   0,  91,  88,  93,  84, 105,  14,
+      39, 104,   0,  77,   0,  18,  85, 107,  32,   0, 117,  76, 109,
+      59,  46,  80,   0,   0,  90,  40,   0, 112,   0,  36,   0,   0,
+      29,   0,  82,  58,  60,   0,  20,  57,   0,  52,
+  };
+  static const unsigned char aNext[121] = {
+       0,   0,   0,   0,   4,   0,   0,   0,   0,   0,   0,   0,   0,
+       0,   2,   0,   0,   0,   0,   0,   0,  13,   0,   0,   0,   0,
+       0,   7,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+       0,   0,   0,   0,   0,  33,  21,   0,   0,   0,  43,   3,  47,
+       0,   0,   0,   0,  30,  54,   0,   0,  38,   0,   0,   0,   1,
+      62,   0,   0,  63,   0,  41,   0,   0,   0,   0,   0,   0,   0,
+      61,   0,   0,   0,   0,  31,  55,  16,  34,  10,   0,   0,   0,
+       0,   0,   0,   0,  11,  68,  75,   0,   8,   0, 100,  94,   0,
+     103,   0,  83,   0,  71,   0,   0, 110,  27,  37,  69,  79,   0,
+      35,  64,   0,   0,
+  };
+  static const unsigned char aLen[121] = {
+       7,   7,   5,   4,   6,   4,   5,   3,   6,   7,   3,   6,   6,
+       7,   7,   3,   8,   2,   6,   5,   4,   4,   3,  10,   4,   6,
+      11,   6,   2,   7,   5,   5,   9,   6,   9,   9,   7,  10,  10,
+       4,   6,   2,   3,   4,   9,   2,   6,   5,   6,   6,   5,   6,
+       5,   5,   7,   7,   7,   2,   3,   4,   4,   7,   3,   6,   4,
+       7,   6,  12,   6,   9,   4,   6,   5,   4,   7,   6,   5,   6,
+       7,   5,   4,   5,   6,   5,   7,   3,   7,  13,   2,   2,   4,
+       6,   6,   8,   5,  17,  12,   7,   8,   8,   2,   4,   4,   4,
+       4,   4,   2,   2,   6,   5,   8,   5,   5,   8,   3,   5,   5,
+       6,   4,   9,   3,
+  };
+  static const unsigned short int aOffset[121] = {
+       0,   2,   2,   8,   9,  14,  16,  20,  23,  25,  25,  29,  33,
+      36,  41,  46,  48,  53,  54,  59,  62,  65,  67,  69,  78,  81,
+      86,  91,  95,  96, 101, 105, 109, 117, 122, 128, 136, 142, 152,
+     159, 162, 162, 165, 167, 167, 171, 176, 179, 184, 189, 194, 197,
+     203, 206, 210, 217, 223, 223, 223, 226, 229, 233, 234, 238, 244,
+     248, 255, 261, 273, 279, 288, 290, 296, 301, 303, 310, 315, 320,
+     326, 332, 337, 341, 344, 350, 354, 361, 363, 370, 372, 374, 383,
+     387, 393, 399, 407, 412, 412, 428, 435, 442, 443, 450, 454, 458,
+     462, 466, 469, 471, 473, 479, 483, 491, 495, 500, 508, 511, 516,
+     521, 527, 531, 536,
+  };
+  static const unsigned char aCode[121] = {
+    TK_REINDEX,    TK_INDEXED,    TK_INDEX,      TK_DESC,       TK_ESCAPE,     
+    TK_EACH,       TK_CHECK,      TK_KEY,        TK_BEFORE,     TK_FOREIGN,    
+    TK_FOR,        TK_IGNORE,     TK_LIKE_KW,    TK_EXPLAIN,    TK_INSTEAD,    
+    TK_ADD,        TK_DATABASE,   TK_AS,         TK_SELECT,     TK_TABLE,      
+    TK_JOIN_KW,    TK_THEN,       TK_END,        TK_DEFERRABLE, TK_ELSE,       
+    TK_EXCEPT,     TK_TRANSACTION,TK_ACTION,     TK_ON,         TK_JOIN_KW,    
+    TK_ALTER,      TK_RAISE,      TK_EXCLUSIVE,  TK_EXISTS,     TK_SAVEPOINT,  
+    TK_INTERSECT,  TK_TRIGGER,    TK_REFERENCES, TK_CONSTRAINT, TK_INTO,       
+    TK_OFFSET,     TK_OF,         TK_SET,        TK_TEMP,       TK_TEMP,       
+    TK_OR,         TK_UNIQUE,     TK_QUERY,      TK_ATTACH,     TK_HAVING,     
+    TK_GROUP,      TK_UPDATE,     TK_BEGIN,      TK_JOIN_KW,    TK_RELEASE,    
+    TK_BETWEEN,    TK_NOTNULL,    TK_NO,         TK_NOT,        TK_NULL,       
+    TK_LIKE_KW,    TK_CASCADE,    TK_ASC,        TK_DELETE,     TK_CASE,       
+    TK_COLLATE,    TK_CREATE,     TK_CTIME_KW,   TK_DETACH,     TK_IMMEDIATE,  
+    TK_JOIN,       TK_INSERT,     TK_MATCH,      TK_PLAN,       TK_ANALYZE,    
+    TK_PRAGMA,     TK_ABORT,      TK_VALUES,     TK_VIRTUAL,    TK_LIMIT,      
+    TK_WHEN,       TK_WHERE,      TK_RENAME,     TK_AFTER,      TK_REPLACE,    
+    TK_AND,        TK_DEFAULT,    TK_AUTOINCR,   TK_TO,         TK_IN,         
+    TK_CAST,       TK_COLUMNKW,   TK_COMMIT,     TK_CONFLICT,   TK_JOIN_KW,    
+    TK_CTIME_KW,   TK_CTIME_KW,   TK_PRIMARY,    TK_DEFERRED,   TK_DISTINCT,   
+    TK_IS,         TK_DROP,       TK_FAIL,       TK_FROM,       TK_JOIN_KW,    
+    TK_LIKE_KW,    TK_BY,         TK_IF,         TK_ISNULL,     TK_ORDER,      
+    TK_RESTRICT,   TK_JOIN_KW,    TK_JOIN_KW,    TK_ROLLBACK,   TK_ROW,        
+    TK_UNION,      TK_USING,      TK_VACUUM,     TK_VIEW,       TK_INITIALLY,  
+    TK_ALL,        
+  };
+  int h, i;
+  if( n<2 ) return TK_ID;
+  h = ((charMap(z[0])*4) ^
+      (charMap(z[n-1])*3) ^
+      n) % 127;
+  for(i=((int)aHash[h])-1; i>=0; i=((int)aNext[i])-1){
+    if( aLen[i]==n && sqlite3StrNICmp(&zText[aOffset[i]],z,n)==0 ){
+      testcase( i==0 ); /* REINDEX */
+      testcase( i==1 ); /* INDEXED */
+      testcase( i==2 ); /* INDEX */
+      testcase( i==3 ); /* DESC */
+      testcase( i==4 ); /* ESCAPE */
+      testcase( i==5 ); /* EACH */
+      testcase( i==6 ); /* CHECK */
+      testcase( i==7 ); /* KEY */
+      testcase( i==8 ); /* BEFORE */
+      testcase( i==9 ); /* FOREIGN */
+      testcase( i==10 ); /* FOR */
+      testcase( i==11 ); /* IGNORE */
+      testcase( i==12 ); /* REGEXP */
+      testcase( i==13 ); /* EXPLAIN */
+      testcase( i==14 ); /* INSTEAD */
+      testcase( i==15 ); /* ADD */
+      testcase( i==16 ); /* DATABASE */
+      testcase( i==17 ); /* AS */
+      testcase( i==18 ); /* SELECT */
+      testcase( i==19 ); /* TABLE */
+      testcase( i==20 ); /* LEFT */
+      testcase( i==21 ); /* THEN */
+      testcase( i==22 ); /* END */
+      testcase( i==23 ); /* DEFERRABLE */
+      testcase( i==24 ); /* ELSE */
+      testcase( i==25 ); /* EXCEPT */
+      testcase( i==26 ); /* TRANSACTION */
+      testcase( i==27 ); /* ACTION */
+      testcase( i==28 ); /* ON */
+      testcase( i==29 ); /* NATURAL */
+      testcase( i==30 ); /* ALTER */
+      testcase( i==31 ); /* RAISE */
+      testcase( i==32 ); /* EXCLUSIVE */
+      testcase( i==33 ); /* EXISTS */
+      testcase( i==34 ); /* SAVEPOINT */
+      testcase( i==35 ); /* INTERSECT */
+      testcase( i==36 ); /* TRIGGER */
+      testcase( i==37 ); /* REFERENCES */
+      testcase( i==38 ); /* CONSTRAINT */
+      testcase( i==39 ); /* INTO */
+      testcase( i==40 ); /* OFFSET */
+      testcase( i==41 ); /* OF */
+      testcase( i==42 ); /* SET */
+      testcase( i==43 ); /* TEMP */
+      testcase( i==44 ); /* TEMPORARY */
+      testcase( i==45 ); /* OR */
+      testcase( i==46 ); /* UNIQUE */
+      testcase( i==47 ); /* QUERY */
+      testcase( i==48 ); /* ATTACH */
+      testcase( i==49 ); /* HAVING */
+      testcase( i==50 ); /* GROUP */
+      testcase( i==51 ); /* UPDATE */
+      testcase( i==52 ); /* BEGIN */
+      testcase( i==53 ); /* INNER */
+      testcase( i==54 ); /* RELEASE */
+      testcase( i==55 ); /* BETWEEN */
+      testcase( i==56 ); /* NOTNULL */
+      testcase( i==57 ); /* NO */
+      testcase( i==58 ); /* NOT */
+      testcase( i==59 ); /* NULL */
+      testcase( i==60 ); /* LIKE */
+      testcase( i==61 ); /* CASCADE */
+      testcase( i==62 ); /* ASC */
+      testcase( i==63 ); /* DELETE */
+      testcase( i==64 ); /* CASE */
+      testcase( i==65 ); /* COLLATE */
+      testcase( i==66 ); /* CREATE */
+      testcase( i==67 ); /* CURRENT_DATE */
+      testcase( i==68 ); /* DETACH */
+      testcase( i==69 ); /* IMMEDIATE */
+      testcase( i==70 ); /* JOIN */
+      testcase( i==71 ); /* INSERT */
+      testcase( i==72 ); /* MATCH */
+      testcase( i==73 ); /* PLAN */
+      testcase( i==74 ); /* ANALYZE */
+      testcase( i==75 ); /* PRAGMA */
+      testcase( i==76 ); /* ABORT */
+      testcase( i==77 ); /* VALUES */
+      testcase( i==78 ); /* VIRTUAL */
+      testcase( i==79 ); /* LIMIT */
+      testcase( i==80 ); /* WHEN */
+      testcase( i==81 ); /* WHERE */
+      testcase( i==82 ); /* RENAME */
+      testcase( i==83 ); /* AFTER */
+      testcase( i==84 ); /* REPLACE */
+      testcase( i==85 ); /* AND */
+      testcase( i==86 ); /* DEFAULT */
+      testcase( i==87 ); /* AUTOINCREMENT */
+      testcase( i==88 ); /* TO */
+      testcase( i==89 ); /* IN */
+      testcase( i==90 ); /* CAST */
+      testcase( i==91 ); /* COLUMN */
+      testcase( i==92 ); /* COMMIT */
+      testcase( i==93 ); /* CONFLICT */
+      testcase( i==94 ); /* CROSS */
+      testcase( i==95 ); /* CURRENT_TIMESTAMP */
+      testcase( i==96 ); /* CURRENT_TIME */
+      testcase( i==97 ); /* PRIMARY */
+      testcase( i==98 ); /* DEFERRED */
+      testcase( i==99 ); /* DISTINCT */
+      testcase( i==100 ); /* IS */
+      testcase( i==101 ); /* DROP */
+      testcase( i==102 ); /* FAIL */
+      testcase( i==103 ); /* FROM */
+      testcase( i==104 ); /* FULL */
+      testcase( i==105 ); /* GLOB */
+      testcase( i==106 ); /* BY */
+      testcase( i==107 ); /* IF */
+      testcase( i==108 ); /* ISNULL */
+      testcase( i==109 ); /* ORDER */
+      testcase( i==110 ); /* RESTRICT */
+      testcase( i==111 ); /* OUTER */
+      testcase( i==112 ); /* RIGHT */
+      testcase( i==113 ); /* ROLLBACK */
+      testcase( i==114 ); /* ROW */
+      testcase( i==115 ); /* UNION */
+      testcase( i==116 ); /* USING */
+      testcase( i==117 ); /* VACUUM */
+      testcase( i==118 ); /* VIEW */
+      testcase( i==119 ); /* INITIALLY */
+      testcase( i==120 ); /* ALL */
+      return aCode[i];
+    }
   }
-  return 1;
+  return TK_ID;
 }
+SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char *z, int n){
+  return keywordCode((char*)z, n);
+}
+
+/************** End of keywordhash.h *****************************************/
+/************** Continuing where we left off in tokenize.c *******************/
+
 
 /*
-** Return true if the given term of an OR clause can be ignored during
-** a check to make sure all OR terms are candidates for optimization.
-** In other words, return true if a call to the orTermIsOptCandidate()
-** above returned false but it is not necessary to disqualify the
-** optimization.
-**
-** Suppose the original OR phrase was this:
-**
-**           a=4  OR  a=11  OR  a=b
+** If X is a character that can be used in an identifier then
+** IdChar(X) will be true.  Otherwise it is false.
 **
-** During analysis, the third term gets flipped around and duplicate
-** so that we are left with this:
+** For ASCII, any character with the high-order bit set is
+** allowed in an identifier.  For 7-bit characters, 
+** sqlite3IsIdChar[X] must be 1.
 **
-**           a=4  OR  a=11  OR  a=b  OR  b=a
+** For EBCDIC, the rules are more complex but have the same
+** end result.
 **
-** Since the last two terms are duplicates, only one of them
-** has to qualify in order for the whole phrase to qualify.  When
-** this routine is called, we know that pOrTerm did not qualify.
-** This routine merely checks to see if pOrTerm has a duplicate that
-** might qualify.  If there is a duplicate that has not yet been
-** disqualified, then return true.  If there are no duplicates, or
-** the duplicate has also been disqualifed, return false.
+** Ticket #1066.  the SQL standard does not allow '$' in the
+** middle of identfiers.  But many SQL implementations do. 
+** SQLite will allow '$' in identifiers for compatibility.
+** But the feature is undocumented.
 */
-static int orTermHasOkDuplicate(WhereClause *pOr, WhereTerm *pOrTerm){
-  if( pOrTerm->flags & TERM_COPIED ){
-    /* This is the original term.  The duplicate is to the left had
-    ** has not yet been analyzed and thus has not yet been disqualified. */
-    return 1;
-  }
-  if( (pOrTerm->flags & TERM_VIRTUAL)!=0
-     && (pOr->a[pOrTerm->iParent].flags & TERM_OR_OK)!=0 ){
-    /* This is a duplicate term.  The original qualified so this one
-    ** does not have to. */
-    return 1;
-  }
-  /* This is either a singleton term or else it is a duplicate for
-  ** which the original did not qualify.  Either way we are done for. */
-  return 0;
-}
-#endif /* !SQLITE_OMIT_OR_OPTIMIZATION && !SQLITE_OMIT_SUBQUERY */
+#ifdef SQLITE_ASCII
+SQLITE_PRIVATE const char sqlite3IsAsciiIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* 2x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
+};
+#define IdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && sqlite3IsAsciiIdChar[c-0x20]))
+#endif
+#ifdef SQLITE_EBCDIC
+SQLITE_PRIVATE const char sqlite3IsEbcdicIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 4x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0,  /* 5x */
+    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0,  /* 6x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,  /* 7x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0,  /* 8x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0,  /* 9x */
+    1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0,  /* Ax */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* Bx */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Cx */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Dx */
+    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Ex */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0,  /* Fx */
+};
+#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
+#endif
+
 
 /*
-** The input to this routine is an WhereTerm structure with only the
-** "pExpr" field filled in.  The job of this routine is to analyze the
-** subexpression and populate all the other fields of the WhereTerm
-** structure.
-**
-** If the expression is of the form "<expr> <op> X" it gets commuted
-** to the standard form of "X <op> <expr>".  If the expression is of
-** the form "X <op> Y" where both X and Y are columns, then the original
-** expression is unchanged and a new virtual expression of the form
-** "Y <op> X" is added to the WHERE clause and analyzed separately.
+** Return the length of the token that begins at z[0]. 
+** Store the token type in *tokenType before returning.
 */
-static void exprAnalyze(
-  SrcList *pSrc,            /* the FROM clause */
-  WhereClause *pWC,         /* the WHERE clause */
-  int idxTerm               /* Index of the term to be analyzed */
-){
-  WhereTerm *pTerm;
-  ExprMaskSet *pMaskSet;
-  Expr *pExpr;
-  Bitmask prereqLeft;
-  Bitmask prereqAll;
-  Bitmask extraRight = 0;
-  int nPattern;
-  int isComplete;
-  int noCase;
-  int op;
-  Parse *pParse = pWC->pParse;
-  sqlite3 *db = pParse->db;
-
-  if( db->mallocFailed ){
-    return;
-  }
-  pTerm = &pWC->a[idxTerm];
-  pMaskSet = pWC->pMaskSet;
-  pExpr = pTerm->pExpr;
-  prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
-  op = pExpr->op;
-  if( op==TK_IN ){
-    assert( pExpr->pRight==0 );
-    pTerm->prereqRight = exprListTableUsage(pMaskSet, pExpr->pList)
-                          | exprSelectTableUsage(pMaskSet, pExpr->pSelect);
-  }else if( op==TK_ISNULL ){
-    pTerm->prereqRight = 0;
-  }else{
-    pTerm->prereqRight = exprTableUsage(pMaskSet, pExpr->pRight);
-  }
-  prereqAll = exprTableUsage(pMaskSet, pExpr);
-  if( ExprHasProperty(pExpr, EP_FromJoin) ){
-    Bitmask x = getMask(pMaskSet, pExpr->iRightJoinTable);
-    prereqAll |= x;
-    extraRight = x-1;  /* ON clause terms may not be used with an index
-                       ** on left table of a LEFT JOIN.  Ticket #3015 */
-  }
-  pTerm->prereqAll = prereqAll;
-  pTerm->leftCursor = -1;
-  pTerm->iParent = -1;
-  pTerm->eOperator = 0;
-  if( allowedOp(op) && (pTerm->prereqRight & prereqLeft)==0 ){
-    Expr *pLeft = pExpr->pLeft;
-    Expr *pRight = pExpr->pRight;
-    if( pLeft->op==TK_COLUMN ){
-      pTerm->leftCursor = pLeft->iTable;
-      pTerm->leftColumn = pLeft->iColumn;
-      pTerm->eOperator = operatorMask(op);
+SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
+  int i, c;
+  switch( *z ){
+    case ' ': case '\t': case '\n': case '\f': case '\r': {
+      testcase( z[0]==' ' );
+      testcase( z[0]=='\t' );
+      testcase( z[0]=='\n' );
+      testcase( z[0]=='\f' );
+      testcase( z[0]=='\r' );
+      for(i=1; sqlite3Isspace(z[i]); i++){}
+      *tokenType = TK_SPACE;
+      return i;
     }
-    if( pRight && pRight->op==TK_COLUMN ){
-      WhereTerm *pNew;
-      Expr *pDup;
-      if( pTerm->leftCursor>=0 ){
-        int idxNew;
-        pDup = sqlite3ExprDup(db, pExpr);
-        if( db->mallocFailed ){
-          sqlite3ExprDelete(pDup);
-          return;
-        }
-        idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
-        if( idxNew==0 ) return;
-        pNew = &pWC->a[idxNew];
-        pNew->iParent = idxTerm;
-        pTerm = &pWC->a[idxTerm];
-        pTerm->nChild = 1;
-        pTerm->flags |= TERM_COPIED;
+    case '-': {
+      if( z[1]=='-' ){
+        for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
+        *tokenType = TK_SPACE;
+        return i;
+      }
+      *tokenType = TK_MINUS;
+      return 1;
+    }
+    case '(': {
+      *tokenType = TK_LP;
+      return 1;
+    }
+    case ')': {
+      *tokenType = TK_RP;
+      return 1;
+    }
+    case ';': {
+      *tokenType = TK_SEMI;
+      return 1;
+    }
+    case '+': {
+      *tokenType = TK_PLUS;
+      return 1;
+    }
+    case '*': {
+      *tokenType = TK_STAR;
+      return 1;
+    }
+    case '/': {
+      if( z[1]!='*' || z[2]==0 ){
+        *tokenType = TK_SLASH;
+        return 1;
+      }
+      for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
+      if( c ) i++;
+      *tokenType = TK_SPACE;
+      return i;
+    }
+    case '%': {
+      *tokenType = TK_REM;
+      return 1;
+    }
+    case '=': {
+      *tokenType = TK_EQ;
+      return 1 + (z[1]=='=');
+    }
+    case '<': {
+      if( (c=z[1])=='=' ){
+        *tokenType = TK_LE;
+        return 2;
+      }else if( c=='>' ){
+        *tokenType = TK_NE;
+        return 2;
+      }else if( c=='<' ){
+        *tokenType = TK_LSHIFT;
+        return 2;
       }else{
-        pDup = pExpr;
-        pNew = pTerm;
+        *tokenType = TK_LT;
+        return 1;
       }
-      exprCommute(pDup);
-      pLeft = pDup->pLeft;
-      pNew->leftCursor = pLeft->iTable;
-      pNew->leftColumn = pLeft->iColumn;
-      pNew->prereqRight = prereqLeft;
-      pNew->prereqAll = prereqAll;
-      pNew->eOperator = operatorMask(pDup->op);
     }
-  }
-
-#ifndef SQLITE_OMIT_BETWEEN_OPTIMIZATION
-  /* If a term is the BETWEEN operator, create two new virtual terms
-  ** that define the range that the BETWEEN implements.
-  */
-  else if( pExpr->op==TK_BETWEEN ){
-    ExprList *pList = pExpr->pList;
-    int i;
-    static const u8 ops[] = {TK_GE, TK_LE};
-    assert( pList!=0 );
-    assert( pList->nExpr==2 );
-    for(i=0; i<2; i++){
-      Expr *pNewExpr;
-      int idxNew;
-      pNewExpr = sqlite3Expr(db, ops[i], sqlite3ExprDup(db, pExpr->pLeft),
-                             sqlite3ExprDup(db, pList->a[i].pExpr), 0);
-      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
-      exprAnalyze(pSrc, pWC, idxNew);
-      pTerm = &pWC->a[idxTerm];
-      pWC->a[idxNew].iParent = idxTerm;
+    case '>': {
+      if( (c=z[1])=='=' ){
+        *tokenType = TK_GE;
+        return 2;
+      }else if( c=='>' ){
+        *tokenType = TK_RSHIFT;
+        return 2;
+      }else{
+        *tokenType = TK_GT;
+        return 1;
+      }
     }
-    pTerm->nChild = 2;
-  }
-#endif /* SQLITE_OMIT_BETWEEN_OPTIMIZATION */
-
-#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
-  /* Attempt to convert OR-connected terms into an IN operator so that
-  ** they can make use of indices.  Example:
-  **
-  **      x = expr1  OR  expr2 = x  OR  x = expr3
-  **
-  ** is converted into
-  **
-  **      x IN (expr1,expr2,expr3)
-  **
-  ** This optimization must be omitted if OMIT_SUBQUERY is defined because
-  ** the compiler for the the IN operator is part of sub-queries.
-  */
-  else if( pExpr->op==TK_OR ){
-    int ok;
-    int i, j;
-    int iColumn, iCursor;
-    WhereClause sOr;
-    WhereTerm *pOrTerm;
-
-    assert( (pTerm->flags & TERM_DYNAMIC)==0 );
-    whereClauseInit(&sOr, pWC->pParse, pMaskSet);
-    whereSplit(&sOr, pExpr, TK_OR);
-    exprAnalyzeAll(pSrc, &sOr);
-    assert( sOr.nTerm>=2 );
-    j = 0;
-    if( db->mallocFailed ) goto or_not_possible;
-    do{
-      assert( j<sOr.nTerm );
-      iColumn = sOr.a[j].leftColumn;
-      iCursor = sOr.a[j].leftCursor;
-      ok = iCursor>=0;
-      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
-        if( pOrTerm->eOperator!=WO_EQ ){
-          goto or_not_possible;
+    case '!': {
+      if( z[1]!='=' ){
+        *tokenType = TK_ILLEGAL;
+        return 2;
+      }else{
+        *tokenType = TK_NE;
+        return 2;
+      }
+    }
+    case '|': {
+      if( z[1]!='|' ){
+        *tokenType = TK_BITOR;
+        return 1;
+      }else{
+        *tokenType = TK_CONCAT;
+        return 2;
+      }
+    }
+    case ',': {
+      *tokenType = TK_COMMA;
+      return 1;
+    }
+    case '&': {
+      *tokenType = TK_BITAND;
+      return 1;
+    }
+    case '~': {
+      *tokenType = TK_BITNOT;
+      return 1;
+    }
+    case '`':
+    case '\'':
+    case '"': {
+      int delim = z[0];
+      testcase( delim=='`' );
+      testcase( delim=='\'' );
+      testcase( delim=='"' );
+      for(i=1; (c=z[i])!=0; i++){
+        if( c==delim ){
+          if( z[i+1]==delim ){
+            i++;
+          }else{
+            break;
+          }
         }
-        if( orTermIsOptCandidate(pOrTerm, iCursor, iColumn) ){
-          pOrTerm->flags |= TERM_OR_OK;
-        }else if( orTermHasOkDuplicate(&sOr, pOrTerm) ){
-          pOrTerm->flags &= ~TERM_OR_OK;
+      }
+      if( c=='\'' ){
+        *tokenType = TK_STRING;
+        return i+1;
+      }else if( c!=0 ){
+        *tokenType = TK_ID;
+        return i+1;
+      }else{
+        *tokenType = TK_ILLEGAL;
+        return i;
+      }
+    }
+    case '.': {
+#ifndef SQLITE_OMIT_FLOATING_POINT
+      if( !sqlite3Isdigit(z[1]) )
+#endif
+      {
+        *tokenType = TK_DOT;
+        return 1;
+      }
+      /* If the next character is a digit, this is a floating point
+      ** number that begins with ".".  Fall thru into the next case */
+    }
+    case '0': case '1': case '2': case '3': case '4':
+    case '5': case '6': case '7': case '8': case '9': {
+      testcase( z[0]=='0' );  testcase( z[0]=='1' );  testcase( z[0]=='2' );
+      testcase( z[0]=='3' );  testcase( z[0]=='4' );  testcase( z[0]=='5' );
+      testcase( z[0]=='6' );  testcase( z[0]=='7' );  testcase( z[0]=='8' );
+      testcase( z[0]=='9' );
+      *tokenType = TK_INTEGER;
+      for(i=0; sqlite3Isdigit(z[i]); i++){}
+#ifndef SQLITE_OMIT_FLOATING_POINT
+      if( z[i]=='.' ){
+        i++;
+        while( sqlite3Isdigit(z[i]) ){ i++; }
+        *tokenType = TK_FLOAT;
+      }
+      if( (z[i]=='e' || z[i]=='E') &&
+           ( sqlite3Isdigit(z[i+1]) 
+            || ((z[i+1]=='+' || z[i+1]=='-') && sqlite3Isdigit(z[i+2]))
+           )
+      ){
+        i += 2;
+        while( sqlite3Isdigit(z[i]) ){ i++; }
+        *tokenType = TK_FLOAT;
+      }
+#endif
+      while( IdChar(z[i]) ){
+        *tokenType = TK_ILLEGAL;
+        i++;
+      }
+      return i;
+    }
+    case '[': {
+      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
+      *tokenType = c==']' ? TK_ID : TK_ILLEGAL;
+      return i;
+    }
+    case '?': {
+      *tokenType = TK_VARIABLE;
+      for(i=1; sqlite3Isdigit(z[i]); i++){}
+      return i;
+    }
+    case '#': {
+      for(i=1; sqlite3Isdigit(z[i]); i++){}
+      if( i>1 ){
+        /* Parameters of the form #NNN (where NNN is a number) are used
+        ** internally by sqlite3NestedParse.  */
+        *tokenType = TK_REGISTER;
+        return i;
+      }
+      /* Fall through into the next case if the '#' is not followed by
+      ** a digit. Try to match #AAAA where AAAA is a parameter name. */
+    }
+#ifndef SQLITE_OMIT_TCL_VARIABLE
+    case '$':
+#endif
+    case '@':  /* For compatibility with MS SQL Server */
+    case ':': {
+      int n = 0;
+      testcase( z[0]=='$' );  testcase( z[0]=='@' );  testcase( z[0]==':' );
+      *tokenType = TK_VARIABLE;
+      for(i=1; (c=z[i])!=0; i++){
+        if( IdChar(c) ){
+          n++;
+#ifndef SQLITE_OMIT_TCL_VARIABLE
+        }else if( c=='(' && n>0 ){
+          do{
+            i++;
+          }while( (c=z[i])!=0 && !sqlite3Isspace(c) && c!=')' );
+          if( c==')' ){
+            i++;
+          }else{
+            *tokenType = TK_ILLEGAL;
+          }
+          break;
+        }else if( c==':' && z[i+1]==':' ){
+          i++;
+#endif
         }else{
-          ok = 0;
+          break;
         }
       }
-    }while( !ok && (sOr.a[j++].flags & TERM_COPIED)!=0 && j<2 );
-    if( ok ){
-      ExprList *pList = 0;
-      Expr *pNew, *pDup;
-      Expr *pLeft = 0;
-      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
-        if( (pOrTerm->flags & TERM_OR_OK)==0 ) continue;
-        pDup = sqlite3ExprDup(db, pOrTerm->pExpr->pRight);
-        pList = sqlite3ExprListAppend(pWC->pParse, pList, pDup, 0);
-        pLeft = pOrTerm->pExpr->pLeft;
-      }
-      assert( pLeft!=0 );
-      pDup = sqlite3ExprDup(db, pLeft);
-      pNew = sqlite3Expr(db, TK_IN, pDup, 0, 0);
-      if( pNew ){
-        int idxNew;
-        transferJoinMarkings(pNew, pExpr);
-        pNew->pList = pList;
-        idxNew = whereClauseInsert(pWC, pNew, TERM_VIRTUAL|TERM_DYNAMIC);
-        exprAnalyze(pSrc, pWC, idxNew);
-        pTerm = &pWC->a[idxTerm];
-        pWC->a[idxNew].iParent = idxTerm;
-        pTerm->nChild = 1;
-      }else{
-        sqlite3ExprListDelete(pList);
-      }
-    }
-or_not_possible:
-    whereClauseClear(&sOr);
-  }
-#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
-
-#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
-  /* Add constraints to reduce the search space on a LIKE or GLOB
-  ** operator.
-  **
-  ** A like pattern of the form "x LIKE 'abc%'" is changed into constraints
-  **
-  **          x>='abc' AND x<'abd' AND x LIKE 'abc%'
-  **
-  ** The last character of the prefix "abc" is incremented to form the
-  ** termination condidtion "abd".  This trick of incrementing the last
-  ** is not 255 and if the character set is not EBCDIC.  
-  */
-  if( isLikeOrGlob(db, pExpr, &nPattern, &isComplete, &noCase) ){
-    Expr *pLeft, *pRight;
-    Expr *pStr1, *pStr2;
-    Expr *pNewExpr1, *pNewExpr2;
-    int idxNew1, idxNew2;
-
-    pLeft = pExpr->pList->a[1].pExpr;
-    pRight = pExpr->pList->a[0].pExpr;
-    pStr1 = sqlite3PExpr(pParse, TK_STRING, 0, 0, 0);
-    if( pStr1 ){
-      sqlite3TokenCopy(db, &pStr1->token, &pRight->token);
-      pStr1->token.n = nPattern;
-      pStr1->flags = EP_Dequoted;
-    }
-    pStr2 = sqlite3ExprDup(db, pStr1);
-    if( !db->mallocFailed ){
-      u8 c, *pC;
-      assert( pStr2->token.dyn );
-      pC = (u8*)&pStr2->token.z[nPattern-1];
-      c = *pC;
-      if( noCase ) c = sqlite3UpperToLower[c];
-      *pC = c + 1;
-    }
-    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft), pStr1, 0);
-    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
-    exprAnalyze(pSrc, pWC, idxNew1);
-    pNewExpr2 = sqlite3PExpr(pParse, TK_LT, sqlite3ExprDup(db,pLeft), pStr2, 0);
-    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
-    exprAnalyze(pSrc, pWC, idxNew2);
-    pTerm = &pWC->a[idxTerm];
-    if( isComplete ){
-      pWC->a[idxNew1].iParent = idxTerm;
-      pWC->a[idxNew2].iParent = idxTerm;
-      pTerm->nChild = 2;
+      if( n==0 ) *tokenType = TK_ILLEGAL;
+      return i;
     }
-  }
-#endif /* SQLITE_OMIT_LIKE_OPTIMIZATION */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  /* Add a WO_MATCH auxiliary term to the constraint set if the
-  ** current expression is of the form:  column MATCH expr.
-  ** This information is used by the xBestIndex methods of
-  ** virtual tables.  The native query optimizer does not attempt
-  ** to do anything with MATCH functions.
-  */
-  if( isMatchOfColumn(pExpr) ){
-    int idxNew;
-    Expr *pRight, *pLeft;
-    WhereTerm *pNewTerm;
-    Bitmask prereqColumn, prereqExpr;
-
-    pRight = pExpr->pList->a[0].pExpr;
-    pLeft = pExpr->pList->a[1].pExpr;
-    prereqExpr = exprTableUsage(pMaskSet, pRight);
-    prereqColumn = exprTableUsage(pMaskSet, pLeft);
-    if( (prereqExpr & prereqColumn)==0 ){
-      Expr *pNewExpr;
-      pNewExpr = sqlite3Expr(db, TK_MATCH, 0, sqlite3ExprDup(db, pRight), 0);
-      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
-      pNewTerm = &pWC->a[idxNew];
-      pNewTerm->prereqRight = prereqExpr;
-      pNewTerm->leftCursor = pLeft->iTable;
-      pNewTerm->leftColumn = pLeft->iColumn;
-      pNewTerm->eOperator = WO_MATCH;
-      pNewTerm->iParent = idxTerm;
-      pTerm = &pWC->a[idxTerm];
-      pTerm->nChild = 1;
-      pTerm->flags |= TERM_COPIED;
-      pNewTerm->prereqAll = pTerm->prereqAll;
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+    case 'x': case 'X': {
+      testcase( z[0]=='x' ); testcase( z[0]=='X' );
+      if( z[1]=='\'' ){
+        *tokenType = TK_BLOB;
+        for(i=2; (c=z[i])!=0 && c!='\''; i++){
+          if( !sqlite3Isxdigit(c) ){
+            *tokenType = TK_ILLEGAL;
+          }
+        }
+        if( i%2 || !c ) *tokenType = TK_ILLEGAL;
+        if( c ) i++;
+        return i;
+      }
+      /* Otherwise fall through to the next case */
     }
-  }
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-  /* Prevent ON clause terms of a LEFT JOIN from being used to drive
-  ** an index for tables to the left of the join.
-  */
-  pTerm->prereqRight |= extraRight;
-}
-
-/*
-** Return TRUE if any of the expressions in pList->a[iFirst...] contain
-** a reference to any table other than the iBase table.
-*/
-static int referencesOtherTables(
-  ExprList *pList,          /* Search expressions in ths list */
-  ExprMaskSet *pMaskSet,    /* Mapping from tables to bitmaps */
-  int iFirst,               /* Be searching with the iFirst-th expression */
-  int iBase                 /* Ignore references to this table */
-){
-  Bitmask allowed = ~getMask(pMaskSet, iBase);
-  while( iFirst<pList->nExpr ){
-    if( (exprTableUsage(pMaskSet, pList->a[iFirst++].pExpr)&allowed)!=0 ){
-      return 1;
+#endif
+    default: {
+      if( !IdChar(*z) ){
+        break;
+      }
+      for(i=1; IdChar(z[i]); i++){}
+      *tokenType = keywordCode((char*)z, i);
+      return i;
     }
   }
-  return 0;
+  *tokenType = TK_ILLEGAL;
+  return 1;
 }
 
-
 /*
-** This routine decides if pIdx can be used to satisfy the ORDER BY
-** clause.  If it can, it returns 1.  If pIdx cannot satisfy the
-** ORDER BY clause, this routine returns 0.
-**
-** pOrderBy is an ORDER BY clause from a SELECT statement.  pTab is the
-** left-most table in the FROM clause of that same SELECT statement and
-** the table has a cursor number of "base".  pIdx is an index on pTab.
-**
-** nEqCol is the number of columns of pIdx that are used as equality
-** constraints.  Any of these columns may be missing from the ORDER BY
-** clause and the match can still be a success.
-**
-** All terms of the ORDER BY that match against the index must be either
-** ASC or DESC.  (Terms of the ORDER BY clause past the end of a UNIQUE
-** index do not need to satisfy this constraint.)  The *pbRev value is
-** set to 1 if the ORDER BY clause is all DESC and it is set to 0 if
-** the ORDER BY clause is all ASC.
+** Run the parser on the given SQL string.  The parser structure is
+** passed in.  An SQLITE_ status code is returned.  If an error occurs
+** then an and attempt is made to write an error message into 
+** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that
+** error message.
 */
-static int isSortingIndex(
-  Parse *pParse,          /* Parsing context */
-  ExprMaskSet *pMaskSet,  /* Mapping from table indices to bitmaps */
-  Index *pIdx,            /* The index we are testing */
-  int base,               /* Cursor number for the table to be sorted */
-  ExprList *pOrderBy,     /* The ORDER BY clause */
-  int nEqCol,             /* Number of index columns with == constraints */
-  int *pbRev              /* Set to 1 if ORDER BY is DESC */
-){
-  int i, j;                       /* Loop counters */
-  int sortOrder = 0;              /* XOR of index and ORDER BY sort direction */
-  int nTerm;                      /* Number of ORDER BY terms */
-  struct ExprList_item *pTerm;    /* A term of the ORDER BY clause */
-  sqlite3 *db = pParse->db;
-
-  assert( pOrderBy!=0 );
-  nTerm = pOrderBy->nExpr;
-  assert( nTerm>0 );
+SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
+  int nErr = 0;                   /* Number of errors encountered */
+  int i;                          /* Loop counter */
+  void *pEngine;                  /* The LEMON-generated LALR(1) parser */
+  int tokenType;                  /* type of the next token */
+  int lastTokenParsed = -1;       /* type of the previous token */
+  u8 enableLookaside;             /* Saved value of db->lookaside.bEnabled */
+  sqlite3 *db = pParse->db;       /* The database connection */
+  int mxSqlLen;                   /* Max length of an SQL string */
 
-  /* Match terms of the ORDER BY clause against columns of
-  ** the index.
-  **
-  ** Note that indices have pIdx->nColumn regular columns plus
-  ** one additional column containing the rowid.  The rowid column
-  ** of the index is also allowed to match against the ORDER BY
-  ** clause.
-  */
-  for(i=j=0, pTerm=pOrderBy->a; j<nTerm && i<=pIdx->nColumn; i++){
-    Expr *pExpr;       /* The expression of the ORDER BY pTerm */
-    CollSeq *pColl;    /* The collating sequence of pExpr */
-    int termSortOrder; /* Sort order for this term */
-    int iColumn;       /* The i-th column of the index.  -1 for rowid */
-    int iSortOrder;    /* 1 for DESC, 0 for ASC on the i-th index term */
-    const char *zColl; /* Name of the collating sequence for i-th index term */
 
-    pExpr = pTerm->pExpr;
-    if( pExpr->op!=TK_COLUMN || pExpr->iTable!=base ){
-      /* Can not use an index sort on anything that is not a column in the
-      ** left-most table of the FROM clause */
+  mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
+  if( db->activeVdbeCnt==0 ){
+    db->u1.isInterrupted = 0;
+  }
+  pParse->rc = SQLITE_OK;
+  pParse->zTail = zSql;
+  i = 0;
+  assert( pzErrMsg!=0 );
+  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc);
+  if( pEngine==0 ){
+    db->mallocFailed = 1;
+    return SQLITE_NOMEM;
+  }
+  assert( pParse->pNewTable==0 );
+  assert( pParse->pNewTrigger==0 );
+  assert( pParse->nVar==0 );
+  assert( pParse->nVarExpr==0 );
+  assert( pParse->nVarExprAlloc==0 );
+  assert( pParse->apVarExpr==0 );
+  enableLookaside = db->lookaside.bEnabled;
+  if( db->lookaside.pStart ) db->lookaside.bEnabled = 1;
+  while( !db->mallocFailed && zSql[i]!=0 ){
+    assert( i>=0 );
+    pParse->sLastToken.z = &zSql[i];
+    pParse->sLastToken.n = sqlite3GetToken((unsigned char*)&zSql[i],&tokenType);
+    i += pParse->sLastToken.n;
+    if( i>mxSqlLen ){
+      pParse->rc = SQLITE_TOOBIG;
       break;
     }
-    pColl = sqlite3ExprCollSeq(pParse, pExpr);
-    if( !pColl ){
-      pColl = db->pDfltColl;
-    }
-    if( i<pIdx->nColumn ){
-      iColumn = pIdx->aiColumn[i];
-      if( iColumn==pIdx->pTable->iPKey ){
-        iColumn = -1;
+    switch( tokenType ){
+      case TK_SPACE: {
+        if( db->u1.isInterrupted ){
+          sqlite3ErrorMsg(pParse, "interrupt");
+          pParse->rc = SQLITE_INTERRUPT;
+          goto abort_parse;
+        }
+        break;
       }
-      iSortOrder = pIdx->aSortOrder[i];
-      zColl = pIdx->azColl[i];
-    }else{
-      iColumn = -1;
-      iSortOrder = 0;
-      zColl = pColl->zName;
-    }
-    if( pExpr->iColumn!=iColumn || sqlite3StrICmp(pColl->zName, zColl) ){
-      /* Term j of the ORDER BY clause does not match column i of the index */
-      if( i<nEqCol ){
-        /* If an index column that is constrained by == fails to match an
-        ** ORDER BY term, that is OK.  Just ignore that column of the index
-        */
-        continue;
-      }else{
-        /* If an index column fails to match and is not constrained by ==
-        ** then the index cannot satisfy the ORDER BY constraint.
-        */
-        return 0;
+      case TK_ILLEGAL: {
+        sqlite3DbFree(db, *pzErrMsg);
+        *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"",
+                        &pParse->sLastToken);
+        nErr++;
+        goto abort_parse;
       }
-    }
-    assert( pIdx->aSortOrder!=0 );
-    assert( pTerm->sortOrder==0 || pTerm->sortOrder==1 );
-    assert( iSortOrder==0 || iSortOrder==1 );
-    termSortOrder = iSortOrder ^ pTerm->sortOrder;
-    if( i>nEqCol ){
-      if( termSortOrder!=sortOrder ){
-        /* Indices can only be used if all ORDER BY terms past the
-        ** equality constraints are all either DESC or ASC. */
-        return 0;
+      case TK_SEMI: {
+        pParse->zTail = &zSql[i];
+        /* Fall thru into the default case */
+      }
+      default: {
+        sqlite3Parser(pEngine, tokenType, pParse->sLastToken, pParse);
+        lastTokenParsed = tokenType;
+        if( pParse->rc!=SQLITE_OK ){
+          goto abort_parse;
+        }
+        break;
       }
-    }else{
-      sortOrder = termSortOrder;
-    }
-    j++;
-    pTerm++;
-    if( iColumn<0 && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
-      /* If the indexed column is the primary key and everything matches
-      ** so far and none of the ORDER BY terms to the right reference other
-      ** tables in the join, then we are assured that the index can be used 
-      ** to sort because the primary key is unique and so none of the other
-      ** columns will make any difference
-      */
-      j = nTerm;
     }
   }
-
-  *pbRev = sortOrder!=0;
-  if( j>=nTerm ){
-    /* All terms of the ORDER BY clause are covered by this index so
-    ** this index can be used for sorting. */
-    return 1;
-  }
-  if( pIdx->onError!=OE_None && i==pIdx->nColumn
-      && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
-    /* All terms of this index match some prefix of the ORDER BY clause
-    ** and the index is UNIQUE and no terms on the tail of the ORDER BY
-    ** clause reference other tables in a join.  If this is all true then
-    ** the order by clause is superfluous. */
-    return 1;
+abort_parse:
+  if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
+    if( lastTokenParsed!=TK_SEMI ){
+      sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
+      pParse->zTail = &zSql[i];
+    }
+    sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
   }
-  return 0;
-}
-
-/*
-** Check table to see if the ORDER BY clause in pOrderBy can be satisfied
-** by sorting in order of ROWID.  Return true if so and set *pbRev to be
-** true for reverse ROWID and false for forward ROWID order.
-*/
-static int sortableByRowid(
-  int base,               /* Cursor number for table to be sorted */
-  ExprList *pOrderBy,     /* The ORDER BY clause */
-  ExprMaskSet *pMaskSet,  /* Mapping from tables to bitmaps */
-  int *pbRev              /* Set to 1 if ORDER BY is DESC */
-){
-  Expr *p;
-
-  assert( pOrderBy!=0 );
-  assert( pOrderBy->nExpr>0 );
-  p = pOrderBy->a[0].pExpr;
-  if( p->op==TK_COLUMN && p->iTable==base && p->iColumn==-1
-    && !referencesOtherTables(pOrderBy, pMaskSet, 1, base) ){
-    *pbRev = pOrderBy->a[0].sortOrder;
-    return 1;
+#ifdef YYTRACKMAXSTACKDEPTH
+  sqlite3StatusSet(SQLITE_STATUS_PARSER_STACK,
+      sqlite3ParserStackPeak(pEngine)
+  );
+#endif /* YYDEBUG */
+  sqlite3ParserFree(pEngine, sqlite3_free);
+  db->lookaside.bEnabled = enableLookaside;
+  if( db->mallocFailed ){
+    pParse->rc = SQLITE_NOMEM;
   }
-  return 0;
-}
-
-/*
-** Prepare a crude estimate of the logarithm of the input value.
-** The results need not be exact.  This is only used for estimating
-** the total cost of performing operatings with O(logN) or O(NlogN)
-** complexity.  Because N is just a guess, it is no great tragedy if
-** logN is a little off.
-*/
-static double estLog(double N){
-  double logN = 1;
-  double x = 10;
-  while( N>x ){
-    logN += 1;
-    x *= 10;
+  if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
+    sqlite3SetString(&pParse->zErrMsg, db, "%s", sqlite3ErrStr(pParse->rc));
   }
-  return logN;
-}
-
-/*
-** Two routines for printing the content of an sqlite3_index_info
-** structure.  Used for testing and debugging only.  If neither
-** SQLITE_TEST or SQLITE_DEBUG are defined, then these routines
-** are no-ops.
-*/
-#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_DEBUG)
-static void TRACE_IDX_INPUTS(sqlite3_index_info *p){
-  int i;
-  if( !sqlite3WhereTrace ) return;
-  for(i=0; i<p->nConstraint; i++){
-    sqlite3DebugPrintf("  constraint[%d]: col=%d termid=%d op=%d usabled=%d\n",
-       i,
-       p->aConstraint[i].iColumn,
-       p->aConstraint[i].iTermOffset,
-       p->aConstraint[i].op,
-       p->aConstraint[i].usable);
+  assert( pzErrMsg!=0 );
+  if( pParse->zErrMsg ){
+    *pzErrMsg = pParse->zErrMsg;
+    pParse->zErrMsg = 0;
+    nErr++;
   }
-  for(i=0; i<p->nOrderBy; i++){
-    sqlite3DebugPrintf("  orderby[%d]: col=%d desc=%d\n",
-       i,
-       p->aOrderBy[i].iColumn,
-       p->aOrderBy[i].desc);
+  if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
+    sqlite3VdbeDelete(pParse->pVdbe);
+    pParse->pVdbe = 0;
   }
-}
-static void TRACE_IDX_OUTPUTS(sqlite3_index_info *p){
-  int i;
-  if( !sqlite3WhereTrace ) return;
-  for(i=0; i<p->nConstraint; i++){
-    sqlite3DebugPrintf("  usage[%d]: argvIdx=%d omit=%d\n",
-       i,
-       p->aConstraintUsage[i].argvIndex,
-       p->aConstraintUsage[i].omit);
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  if( pParse->nested==0 ){
+    sqlite3DbFree(db, pParse->aTableLock);
+    pParse->aTableLock = 0;
+    pParse->nTableLock = 0;
   }
-  sqlite3DebugPrintf("  idxNum=%d\n", p->idxNum);
-  sqlite3DebugPrintf("  idxStr=%s\n", p->idxStr);
-  sqlite3DebugPrintf("  orderByConsumed=%d\n", p->orderByConsumed);
-  sqlite3DebugPrintf("  estimatedCost=%g\n", p->estimatedCost);
-}
-#else
-#define TRACE_IDX_INPUTS(A)
-#define TRACE_IDX_OUTPUTS(A)
 #endif
-
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-/*
-** Compute the best index for a virtual table.
-**
-** The best index is computed by the xBestIndex method of the virtual
-** table module.  This routine is really just a wrapper that sets up
-** the sqlite3_index_info structure that is used to communicate with
-** xBestIndex.
-**
-** In a join, this routine might be called multiple times for the
-** same virtual table.  The sqlite3_index_info structure is created
-** and initialized on the first invocation and reused on all subsequent
-** invocations.  The sqlite3_index_info structure is also used when
-** code is generated to access the virtual table.  The whereInfoDelete() 
-** routine takes care of freeing the sqlite3_index_info structure after
-** everybody has finished with it.
-*/
-static double bestVirtualIndex(
-  Parse *pParse,                 /* The parsing context */
-  WhereClause *pWC,              /* The WHERE clause */
-  struct SrcList_item *pSrc,     /* The FROM clause term to search */
-  Bitmask notReady,              /* Mask of cursors that are not available */
-  ExprList *pOrderBy,            /* The order by clause */
-  int orderByUsable,             /* True if we can potential sort */
-  sqlite3_index_info **ppIdxInfo /* Index information passed to xBestIndex */
-){
-  Table *pTab = pSrc->pTab;
-  sqlite3_index_info *pIdxInfo;
-  struct sqlite3_index_constraint *pIdxCons;
-  struct sqlite3_index_orderby *pIdxOrderBy;
-  struct sqlite3_index_constraint_usage *pUsage;
-  WhereTerm *pTerm;
-  int i, j;
-  int nOrderBy;
-  int rc;
-
-  /* If the sqlite3_index_info structure has not been previously
-  ** allocated and initialized for this virtual table, then allocate
-  ** and initialize it now
-  */
-  pIdxInfo = *ppIdxInfo;
-  if( pIdxInfo==0 ){
-    WhereTerm *pTerm;
-    int nTerm;
-    WHERETRACE(("Recomputing index info for %s...\n", pTab->zName));
-
-    /* Count the number of possible WHERE clause constraints referring
-    ** to this virtual table */
-    for(i=nTerm=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
-      if( pTerm->leftCursor != pSrc->iCursor ) continue;
-      if( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
-      testcase( pTerm->eOperator==WO_IN );
-      testcase( pTerm->eOperator==WO_ISNULL );
-      if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
-      nTerm++;
-    }
-
-    /* If the ORDER BY clause contains only columns in the current 
-    ** virtual table then allocate space for the aOrderBy part of
-    ** the sqlite3_index_info structure.
-    */
-    nOrderBy = 0;
-    if( pOrderBy ){
-      for(i=0; i<pOrderBy->nExpr; i++){
-        Expr *pExpr = pOrderBy->a[i].pExpr;
-        if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break;
-      }
-      if( i==pOrderBy->nExpr ){
-        nOrderBy = pOrderBy->nExpr;
-      }
-    }
+  sqlite3DbFree(db, pParse->apVtabLock);
+#endif
 
-    /* Allocate the sqlite3_index_info structure
-    */
-    pIdxInfo = sqlite3DbMallocZero(pParse->db, sizeof(*pIdxInfo)
-                             + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
-                             + sizeof(*pIdxOrderBy)*nOrderBy );
-    if( pIdxInfo==0 ){
-      sqlite3ErrorMsg(pParse, "out of memory");
-      return 0.0;
-    }
-    *ppIdxInfo = pIdxInfo;
-
-    /* Initialize the structure.  The sqlite3_index_info structure contains
-    ** many fields that are declared "const" to prevent xBestIndex from
-    ** changing them.  We have to do some funky casting in order to
-    ** initialize those fields.
+  if( !IN_DECLARE_VTAB ){
+    /* If the pParse->declareVtab flag is set, do not delete any table 
+    ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
+    ** will take responsibility for freeing the Table structure.
     */
-    pIdxCons = (struct sqlite3_index_constraint*)&pIdxInfo[1];
-    pIdxOrderBy = (struct sqlite3_index_orderby*)&pIdxCons[nTerm];
-    pUsage = (struct sqlite3_index_constraint_usage*)&pIdxOrderBy[nOrderBy];
-    *(int*)&pIdxInfo->nConstraint = nTerm;
-    *(int*)&pIdxInfo->nOrderBy = nOrderBy;
-    *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint = pIdxCons;
-    *(struct sqlite3_index_orderby**)&pIdxInfo->aOrderBy = pIdxOrderBy;
-    *(struct sqlite3_index_constraint_usage**)&pIdxInfo->aConstraintUsage =
-                                                                     pUsage;
-
-    for(i=j=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
-      if( pTerm->leftCursor != pSrc->iCursor ) continue;
-      if( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
-      testcase( pTerm->eOperator==WO_IN );
-      testcase( pTerm->eOperator==WO_ISNULL );
-      if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
-      pIdxCons[j].iColumn = pTerm->leftColumn;
-      pIdxCons[j].iTermOffset = i;
-      pIdxCons[j].op = pTerm->eOperator;
-      /* The direct assignment in the previous line is possible only because
-      ** the WO_ and SQLITE_INDEX_CONSTRAINT_ codes are identical.  The
-      ** following asserts verify this fact. */
-      assert( WO_EQ==SQLITE_INDEX_CONSTRAINT_EQ );
-      assert( WO_LT==SQLITE_INDEX_CONSTRAINT_LT );
-      assert( WO_LE==SQLITE_INDEX_CONSTRAINT_LE );
-      assert( WO_GT==SQLITE_INDEX_CONSTRAINT_GT );
-      assert( WO_GE==SQLITE_INDEX_CONSTRAINT_GE );
-      assert( WO_MATCH==SQLITE_INDEX_CONSTRAINT_MATCH );
-      assert( pTerm->eOperator & (WO_EQ|WO_LT|WO_LE|WO_GT|WO_GE|WO_MATCH) );
-      j++;
-    }
-    for(i=0; i<nOrderBy; i++){
-      Expr *pExpr = pOrderBy->a[i].pExpr;
-      pIdxOrderBy[i].iColumn = pExpr->iColumn;
-      pIdxOrderBy[i].desc = pOrderBy->a[i].sortOrder;
-    }
-  }
-
-  /* At this point, the sqlite3_index_info structure that pIdxInfo points
-  ** to will have been initialized, either during the current invocation or
-  ** during some prior invocation.  Now we just have to customize the
-  ** details of pIdxInfo for the current invocation and pass it to
-  ** xBestIndex.
-  */
-
-  /* The module name must be defined. Also, by this point there must
-  ** be a pointer to an sqlite3_vtab structure. Otherwise
-  ** sqlite3ViewGetColumnNames() would have picked up the error. 
-  */
-  assert( pTab->azModuleArg && pTab->azModuleArg[0] );
-  assert( pTab->pVtab );
-#if 0
-  if( pTab->pVtab==0 ){
-    sqlite3ErrorMsg(pParse, "undefined module %s for table %s",
-        pTab->azModuleArg[0], pTab->zName);
-    return 0.0;
+    sqlite3DeleteTable(pParse->pNewTable);
   }
-#endif
 
-  /* Set the aConstraint[].usable fields and initialize all 
-  ** output variables to zero.
-  **
-  ** aConstraint[].usable is true for constraints where the right-hand
-  ** side contains only references to tables to the left of the current
-  ** table.  In other words, if the constraint is of the form:
-  **
-  **           column = expr
-  **
-  ** and we are evaluating a join, then the constraint on column is 
-  ** only valid if all tables referenced in expr occur to the left
-  ** of the table containing column.
-  **
-  ** The aConstraints[] array contains entries for all constraints
-  ** on the current table.  That way we only have to compute it once
-  ** even though we might try to pick the best index multiple times.
-  ** For each attempt at picking an index, the order of tables in the
-  ** join might be different so we have to recompute the usable flag
-  ** each time.
-  */
-  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
-  pUsage = pIdxInfo->aConstraintUsage;
-  for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
-    j = pIdxCons->iTermOffset;
-    pTerm = &pWC->a[j];
-    pIdxCons->usable =  (pTerm->prereqRight & notReady)==0;
+  sqlite3DeleteTrigger(db, pParse->pNewTrigger);
+  sqlite3DbFree(db, pParse->apVarExpr);
+  sqlite3DbFree(db, pParse->aAlias);
+  while( pParse->pAinc ){
+    AutoincInfo *p = pParse->pAinc;
+    pParse->pAinc = p->pNext;
+    sqlite3DbFree(db, p);
   }
-  memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
-  if( pIdxInfo->needToFreeIdxStr ){
-    sqlite3_free(pIdxInfo->idxStr);
+  while( pParse->pZombieTab ){
+    Table *p = pParse->pZombieTab;
+    pParse->pZombieTab = p->pNextZombie;
+    sqlite3DeleteTable(p);
   }
-  pIdxInfo->idxStr = 0;
-  pIdxInfo->idxNum = 0;
-  pIdxInfo->needToFreeIdxStr = 0;
-  pIdxInfo->orderByConsumed = 0;
-  pIdxInfo->estimatedCost = SQLITE_BIG_DBL / 2.0;
-  nOrderBy = pIdxInfo->nOrderBy;
-  if( pIdxInfo->nOrderBy && !orderByUsable ){
-    *(int*)&pIdxInfo->nOrderBy = 0;
+  if( nErr>0 && pParse->rc==SQLITE_OK ){
+    pParse->rc = SQLITE_ERROR;
   }
+  return nErr;
+}
 
-  (void)sqlite3SafetyOff(pParse->db);
-  WHERETRACE(("xBestIndex for %s\n", pTab->zName));
-  TRACE_IDX_INPUTS(pIdxInfo);
-  rc = pTab->pVtab->pModule->xBestIndex(pTab->pVtab, pIdxInfo);
-  TRACE_IDX_OUTPUTS(pIdxInfo);
-  (void)sqlite3SafetyOn(pParse->db);
+/************** End of tokenize.c ********************************************/
+/************** Begin file complete.c ****************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** An tokenizer for SQL
+**
+** This file contains C code that implements the sqlite3_complete() API.
+** This code used to be part of the tokenizer.c source file.  But by
+** separating it out, the code will be automatically omitted from
+** static links that do not use it.
+**
+** $Id: complete.c,v 1.8 2009/04/28 04:46:42 drh Exp $
+*/
+#ifndef SQLITE_OMIT_COMPLETE
 
-  for(i=0; i<pIdxInfo->nConstraint; i++){
-    if( !pIdxInfo->aConstraint[i].usable && pUsage[i].argvIndex>0 ){
-      sqlite3ErrorMsg(pParse, 
-          "table %s: xBestIndex returned an invalid plan", pTab->zName);
-      return 0.0;
-    }
-  }
+/*
+** This is defined in tokenize.c.  We just have to import the definition.
+*/
+#ifndef SQLITE_AMALGAMATION
+#ifdef SQLITE_ASCII
+SQLITE_PRIVATE const char sqlite3IsAsciiIdChar[];
+#define IdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && sqlite3IsAsciiIdChar[c-0x20]))
+#endif
+#ifdef SQLITE_EBCDIC
+SQLITE_PRIVATE const char sqlite3IsEbcdicIdChar[];
+#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
+#endif
+#endif /* SQLITE_AMALGAMATION */
 
-  if( rc!=SQLITE_OK ){
-    if( rc==SQLITE_NOMEM ){
-      pParse->db->mallocFailed = 1;
-    }else {
-      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
-    }
-  }
-  *(int*)&pIdxInfo->nOrderBy = nOrderBy;
 
-  return pIdxInfo->estimatedCost;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
+/*
+** Token types used by the sqlite3_complete() routine.  See the header
+** comments on that procedure for additional information.
+*/
+#define tkSEMI    0
+#define tkWS      1
+#define tkOTHER   2
+#define tkEXPLAIN 3
+#define tkCREATE  4
+#define tkTEMP    5
+#define tkTRIGGER 6
+#define tkEND     7
 
 /*
-** Find the best index for accessing a particular table.  Return a pointer
-** to the index, flags that describe how the index should be used, the
-** number of equality constraints, and the "cost" for this index.
+** Return TRUE if the given SQL string ends in a semicolon.
 **
-** The lowest cost index wins.  The cost is an estimate of the amount of
-** CPU and disk I/O need to process the request using the selected index.
-** Factors that influence cost include:
+** Special handling is require for CREATE TRIGGER statements.
+** Whenever the CREATE TRIGGER keywords are seen, the statement
+** must end with ";END;".
 **
-**    *  The estimated number of rows that will be retrieved.  (The
-**       fewer the better.)
+** This implementation uses a state machine with 7 states:
 **
-**    *  Whether or not sorting must occur.
+**   (0) START     At the beginning or end of an SQL statement.  This routine
+**                 returns 1 if it ends in the START state and 0 if it ends
+**                 in any other state.
 **
-**    *  Whether or not there must be separate lookups in the
-**       index and in the main table.
+**   (1) NORMAL    We are in the middle of statement which ends with a single
+**                 semicolon.
+**
+**   (2) EXPLAIN   The keyword EXPLAIN has been seen at the beginning of 
+**                 a statement.
+**
+**   (3) CREATE    The keyword CREATE has been seen at the beginning of a
+**                 statement, possibly preceeded by EXPLAIN and/or followed by
+**                 TEMP or TEMPORARY
+**
+**   (4) TRIGGER   We are in the middle of a trigger definition that must be
+**                 ended by a semicolon, the keyword END, and another semicolon.
+**
+**   (5) SEMI      We've seen the first semicolon in the ";END;" that occurs at
+**                 the end of a trigger definition.
+**
+**   (6) END       We've seen the ";END" of the ";END;" that occurs at the end
+**                 of a trigger difinition.
+**
+** Transitions between states above are determined by tokens extracted
+** from the input.  The following tokens are significant:
+**
+**   (0) tkSEMI      A semicolon.
+**   (1) tkWS        Whitespace
+**   (2) tkOTHER     Any other SQL token.
+**   (3) tkEXPLAIN   The "explain" keyword.
+**   (4) tkCREATE    The "create" keyword.
+**   (5) tkTEMP      The "temp" or "temporary" keyword.
+**   (6) tkTRIGGER   The "trigger" keyword.
+**   (7) tkEND       The "end" keyword.
+**
+** Whitespace never causes a state transition and is always ignored.
 **
+** If we compile with SQLITE_OMIT_TRIGGER, all of the computation needed
+** to recognize the end of a trigger can be omitted.  All we have to do
+** is look for a semicolon that is not part of an string or comment.
 */
-static double bestIndex(
-  Parse *pParse,              /* The parsing context */
-  WhereClause *pWC,           /* The WHERE clause */
-  struct SrcList_item *pSrc,  /* The FROM clause term to search */
-  Bitmask notReady,           /* Mask of cursors that are not available */
-  ExprList *pOrderBy,         /* The order by clause */
-  Index **ppIndex,            /* Make *ppIndex point to the best index */
-  int *pFlags,                /* Put flags describing this choice in *pFlags */
-  int *pnEq                   /* Put the number of == or IN constraints here */
-){
-  WhereTerm *pTerm;
-  Index *bestIdx = 0;         /* Index that gives the lowest cost */
-  double lowestCost;          /* The cost of using bestIdx */
-  int bestFlags = 0;          /* Flags associated with bestIdx */
-  int bestNEq = 0;            /* Best value for nEq */
-  int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
-  Index *pProbe;              /* An index we are evaluating */
-  int rev;                    /* True to scan in reverse order */
-  int flags;                  /* Flags associated with pProbe */
-  int nEq;                    /* Number of == or IN constraints */
-  int eqTermMask;             /* Mask of valid equality operators */
-  double cost;                /* Cost of using pProbe */
-
-  WHERETRACE(("bestIndex: tbl=%s notReady=%x\n", pSrc->pTab->zName, notReady));
-  lowestCost = SQLITE_BIG_DBL;
-  pProbe = pSrc->pTab->pIndex;
-
-  /* If the table has no indices and there are no terms in the where
-  ** clause that refer to the ROWID, then we will never be able to do
-  ** anything other than a full table scan on this table.  We might as
-  ** well put it first in the join order.  That way, perhaps it can be
-  ** referenced by other tables in the join.
-  */
-  if( pProbe==0 &&
-     findTerm(pWC, iCur, -1, 0, WO_EQ|WO_IN|WO_LT|WO_LE|WO_GT|WO_GE,0)==0 &&
-     (pOrderBy==0 || !sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev)) ){
-    *pFlags = 0;
-    *ppIndex = 0;
-    *pnEq = 0;
-    return 0.0;
-  }
-
-  /* Check for a rowid=EXPR or rowid IN (...) constraints
-  */
-  pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
-  if( pTerm ){
-    Expr *pExpr;
-    *ppIndex = 0;
-    bestFlags = WHERE_ROWID_EQ;
-    if( pTerm->eOperator & WO_EQ ){
-      /* Rowid== is always the best pick.  Look no further.  Because only
-      ** a single row is generated, output is always in sorted order */
-      *pFlags = WHERE_ROWID_EQ | WHERE_UNIQUE;
-      *pnEq = 1;
-      WHERETRACE(("... best is rowid\n"));
-      return 0.0;
-    }else if( (pExpr = pTerm->pExpr)->pList!=0 ){
-      /* Rowid IN (LIST): cost is NlogN where N is the number of list
-      ** elements.  */
-      lowestCost = pExpr->pList->nExpr;
-      lowestCost *= estLog(lowestCost);
-    }else{
-      /* Rowid IN (SELECT): cost is NlogN where N is the number of rows
-      ** in the result of the inner select.  We have no way to estimate
-      ** that value so make a wild guess. */
-      lowestCost = 200;
-    }
-    WHERETRACE(("... rowid IN cost: %.9g\n", lowestCost));
-  }
+SQLITE_API int sqlite3_complete(const char *zSql){
+  u8 state = 0;   /* Current state, using numbers defined in header comment */
+  u8 token;       /* Value of the next token */
 
-  /* Estimate the cost of a table scan.  If we do not know how many
-  ** entries are in the table, use 1 million as a guess.
+#ifndef SQLITE_OMIT_TRIGGER
+  /* A complex statement machine used to detect the end of a CREATE TRIGGER
+  ** statement.  This is the normal case.
   */
-  cost = pProbe ? pProbe->aiRowEst[0] : 1000000;
-  WHERETRACE(("... table scan base cost: %.9g\n", cost));
-  flags = WHERE_ROWID_RANGE;
-
-  /* Check for constraints on a range of rowids in a table scan.
+  static const u8 trans[7][8] = {
+                     /* Token:                                                */
+     /* State:       **  SEMI  WS  OTHER EXPLAIN  CREATE  TEMP  TRIGGER  END  */
+     /* 0   START: */ {    0,  0,     1,      2,      3,    1,       1,   1,  },
+     /* 1  NORMAL: */ {    0,  1,     1,      1,      1,    1,       1,   1,  },
+     /* 2 EXPLAIN: */ {    0,  2,     2,      1,      3,    1,       1,   1,  },
+     /* 3  CREATE: */ {    0,  3,     1,      1,      1,    3,       4,   1,  },
+     /* 4 TRIGGER: */ {    5,  4,     4,      4,      4,    4,       4,   4,  },
+     /* 5    SEMI: */ {    5,  5,     4,      4,      4,    4,       4,   6,  },
+     /* 6     END: */ {    0,  6,     4,      4,      4,    4,       4,   4,  },
+  };
+#else
+  /* If triggers are not suppored by this compile then the statement machine
+  ** used to detect the end of a statement is much simplier
   */
-  pTerm = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE|WO_GT|WO_GE, 0);
-  if( pTerm ){
-    if( findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0) ){
-      flags |= WHERE_TOP_LIMIT;
-      cost /= 3;  /* Guess that rowid<EXPR eliminates two-thirds or rows */
-    }
-    if( findTerm(pWC, iCur, -1, notReady, WO_GT|WO_GE, 0) ){
-      flags |= WHERE_BTM_LIMIT;
-      cost /= 3;  /* Guess that rowid>EXPR eliminates two-thirds of rows */
-    }
-    WHERETRACE(("... rowid range reduces cost to %.9g\n", cost));
-  }else{
-    flags = 0;
-  }
+  static const u8 trans[2][3] = {
+                     /* Token:           */
+     /* State:       **  SEMI  WS  OTHER */
+     /* 0   START: */ {    0,  0,     1, },
+     /* 1  NORMAL: */ {    0,  1,     1, },
+  };
+#endif /* SQLITE_OMIT_TRIGGER */
 
-  /* If the table scan does not satisfy the ORDER BY clause, increase
-  ** the cost by NlogN to cover the expense of sorting. */
-  if( pOrderBy ){
-    if( sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev) ){
-      flags |= WHERE_ORDERBY|WHERE_ROWID_RANGE;
-      if( rev ){
-        flags |= WHERE_REVERSE;
+  while( *zSql ){
+    switch( *zSql ){
+      case ';': {  /* A semicolon */
+        token = tkSEMI;
+        break;
       }
-    }else{
-      cost += cost*estLog(cost);
-      WHERETRACE(("... sorting increases cost to %.9g\n", cost));
-    }
-  }
-  if( cost<lowestCost ){
-    lowestCost = cost;
-    bestFlags = flags;
-  }
-
-  /* If the pSrc table is the right table of a LEFT JOIN then we may not
-  ** use an index to satisfy IS NULL constraints on that table.  This is
-  ** because columns might end up being NULL if the table does not match -
-  ** a circumstance which the index cannot help us discover.  Ticket #2177.
-  */
-  if( (pSrc->jointype & JT_LEFT)!=0 ){
-    eqTermMask = WO_EQ|WO_IN;
-  }else{
-    eqTermMask = WO_EQ|WO_IN|WO_ISNULL;
-  }
-
-  /* Look at each index.
-  */
-  for(; pProbe; pProbe=pProbe->pNext){
-    int i;                       /* Loop counter */
-    double inMultiplier = 1;
-
-    WHERETRACE(("... index %s:\n", pProbe->zName));
-
-    /* Count the number of columns in the index that are satisfied
-    ** by x=EXPR constraints or x IN (...) constraints.
-    */
-    flags = 0;
-    for(i=0; i<pProbe->nColumn; i++){
-      int j = pProbe->aiColumn[i];
-      pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pProbe);
-      if( pTerm==0 ) break;
-      flags |= WHERE_COLUMN_EQ;
-      if( pTerm->eOperator & WO_IN ){
-        Expr *pExpr = pTerm->pExpr;
-        flags |= WHERE_COLUMN_IN;
-        if( pExpr->pSelect!=0 ){
-          inMultiplier *= 25;
-        }else if( pExpr->pList!=0 ){
-          inMultiplier *= pExpr->pList->nExpr + 1;
-        }
+      case ' ':
+      case '\r':
+      case '\t':
+      case '\n':
+      case '\f': {  /* White space is ignored */
+        token = tkWS;
+        break;
       }
-    }
-    cost = pProbe->aiRowEst[i] * inMultiplier * estLog(inMultiplier);
-    nEq = i;
-    if( pProbe->onError!=OE_None && (flags & WHERE_COLUMN_IN)==0
-         && nEq==pProbe->nColumn ){
-      flags |= WHERE_UNIQUE;
-    }
-    WHERETRACE(("...... nEq=%d inMult=%.9g cost=%.9g\n",nEq,inMultiplier,cost));
-
-    /* Look for range constraints
-    */
-    if( nEq<pProbe->nColumn ){
-      int j = pProbe->aiColumn[nEq];
-      pTerm = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pProbe);
-      if( pTerm ){
-        flags |= WHERE_COLUMN_RANGE;
-        if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pProbe) ){
-          flags |= WHERE_TOP_LIMIT;
-          cost /= 3;
-        }
-        if( findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pProbe) ){
-          flags |= WHERE_BTM_LIMIT;
-          cost /= 3;
+      case '/': {   /* C-style comments */
+        if( zSql[1]!='*' ){
+          token = tkOTHER;
+          break;
         }
-        WHERETRACE(("...... range reduces cost to %.9g\n", cost));
+        zSql += 2;
+        while( zSql[0] && (zSql[0]!='*' || zSql[1]!='/') ){ zSql++; }
+        if( zSql[0]==0 ) return 0;
+        zSql++;
+        token = tkWS;
+        break;
       }
-    }
-
-    /* Add the additional cost of sorting if that is a factor.
-    */
-    if( pOrderBy ){
-      if( (flags & WHERE_COLUMN_IN)==0 &&
-           isSortingIndex(pParse,pWC->pMaskSet,pProbe,iCur,pOrderBy,nEq,&rev) ){
-        if( flags==0 ){
-          flags = WHERE_COLUMN_RANGE;
-        }
-        flags |= WHERE_ORDERBY;
-        if( rev ){
-          flags |= WHERE_REVERSE;
+      case '-': {   /* SQL-style comments from "--" to end of line */
+        if( zSql[1]!='-' ){
+          token = tkOTHER;
+          break;
         }
-      }else{
-        cost += cost*estLog(cost);
-        WHERETRACE(("...... orderby increases cost to %.9g\n", cost));
+        while( *zSql && *zSql!='\n' ){ zSql++; }
+        if( *zSql==0 ) return state==0;
+        token = tkWS;
+        break;
       }
-    }
-
-    /* Check to see if we can get away with using just the index without
-    ** ever reading the table.  If that is the case, then halve the
-    ** cost of this index.
-    */
-    if( flags && pSrc->colUsed < (((Bitmask)1)<<(BMS-1)) ){
-      Bitmask m = pSrc->colUsed;
-      int j;
-      for(j=0; j<pProbe->nColumn; j++){
-        int x = pProbe->aiColumn[j];
-        if( x<BMS-1 ){
-          m &= ~(((Bitmask)1)<<x);
-        }
+      case '[': {   /* Microsoft-style identifiers in [...] */
+        zSql++;
+        while( *zSql && *zSql!=']' ){ zSql++; }
+        if( *zSql==0 ) return 0;
+        token = tkOTHER;
+        break;
       }
-      if( m==0 ){
-        flags |= WHERE_IDX_ONLY;
-        cost /= 2;
-        WHERETRACE(("...... idx-only reduces cost to %.9g\n", cost));
+      case '`':     /* Grave-accent quoted symbols used by MySQL */
+      case '"':     /* single- and double-quoted strings */
+      case '\'': {
+        int c = *zSql;
+        zSql++;
+        while( *zSql && *zSql!=c ){ zSql++; }
+        if( *zSql==0 ) return 0;
+        token = tkOTHER;
+        break;
+      }
+      default: {
+        int c;
+        if( IdChar((u8)*zSql) ){
+          /* Keywords and unquoted identifiers */
+          int nId;
+          for(nId=1; IdChar(zSql[nId]); nId++){}
+#ifdef SQLITE_OMIT_TRIGGER
+          token = tkOTHER;
+#else
+          switch( *zSql ){
+            case 'c': case 'C': {
+              if( nId==6 && sqlite3StrNICmp(zSql, "create", 6)==0 ){
+                token = tkCREATE;
+              }else{
+                token = tkOTHER;
+              }
+              break;
+            }
+            case 't': case 'T': {
+              if( nId==7 && sqlite3StrNICmp(zSql, "trigger", 7)==0 ){
+                token = tkTRIGGER;
+              }else if( nId==4 && sqlite3StrNICmp(zSql, "temp", 4)==0 ){
+                token = tkTEMP;
+              }else if( nId==9 && sqlite3StrNICmp(zSql, "temporary", 9)==0 ){
+                token = tkTEMP;
+              }else{
+                token = tkOTHER;
+              }
+              break;
+            }
+            case 'e':  case 'E': {
+              if( nId==3 && sqlite3StrNICmp(zSql, "end", 3)==0 ){
+                token = tkEND;
+              }else
+#ifndef SQLITE_OMIT_EXPLAIN
+              if( nId==7 && sqlite3StrNICmp(zSql, "explain", 7)==0 ){
+                token = tkEXPLAIN;
+              }else
+#endif
+              {
+                token = tkOTHER;
+              }
+              break;
+            }
+            default: {
+              token = tkOTHER;
+              break;
+            }
+          }
+#endif /* SQLITE_OMIT_TRIGGER */
+          zSql += nId-1;
+        }else{
+          /* Operators and special symbols */
+          token = tkOTHER;
+        }
+        break;
       }
     }
-
-    /* If this index has achieved the lowest cost so far, then use it.
-    */
-    if( flags && cost < lowestCost ){
-      bestIdx = pProbe;
-      lowestCost = cost;
-      bestFlags = flags;
-      bestNEq = nEq;
-    }
+    state = trans[state][token];
+    zSql++;
   }
-
-  /* Report the best result
-  */
-  *ppIndex = bestIdx;
-  WHERETRACE(("best index is %s, cost=%.9g, flags=%x, nEq=%d\n",
-        bestIdx ? bestIdx->zName : "(none)", lowestCost, bestFlags, bestNEq));
-  *pFlags = bestFlags | eqTermMask;
-  *pnEq = bestNEq;
-  return lowestCost;
+  return state==0;
 }
 
+#ifndef SQLITE_OMIT_UTF16
+/*
+** This routine is the same as the sqlite3_complete() routine described
+** above, except that the parameter is required to be UTF-16 encoded, not
+** UTF-8.
+*/
+SQLITE_API int sqlite3_complete16(const void *zSql){
+  sqlite3_value *pVal;
+  char const *zSql8;
+  int rc = SQLITE_NOMEM;
+
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
+  pVal = sqlite3ValueNew(0);
+  sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC);
+  zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8);
+  if( zSql8 ){
+    rc = sqlite3_complete(zSql8);
+  }else{
+    rc = SQLITE_NOMEM;
+  }
+  sqlite3ValueFree(pVal);
+  return sqlite3ApiExit(0, rc);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+#endif /* SQLITE_OMIT_COMPLETE */
 
+/************** End of complete.c ********************************************/
+/************** Begin file main.c ********************************************/
 /*
-** Disable a term in the WHERE clause.  Except, do not disable the term
-** if it controls a LEFT OUTER JOIN and it did not originate in the ON
-** or USING clause of that join.
-**
-** Consider the term t2.z='ok' in the following queries:
+** 2001 September 15
 **
-**   (1)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x WHERE t2.z='ok'
-**   (2)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x AND t2.z='ok'
-**   (3)  SELECT * FROM t1, t2 WHERE t1.a=t2.x AND t2.z='ok'
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** The t2.z='ok' is disabled in the in (2) because it originates
-** in the ON clause.  The term is disabled in (3) because it is not part
-** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** Disabling a term causes that term to not be tested in the inner loop
-** of the join.  Disabling is an optimization.  When terms are satisfied
-** by indices, we disable them to prevent redundant tests in the inner
-** loop.  We would get the correct results if nothing were ever disabled,
-** but joins might run a little slower.  The trick is to disable as much
-** as we can without disabling too much.  If we disabled in (1), we'd get
-** the wrong answer.  See ticket #813.
+*************************************************************************
+** Main file for the SQLite library.  The routines in this file
+** implement the programmer interface to the library.  Routines in
+** other files are for internal use by SQLite and should not be
+** accessed by users of the library.
 */
-static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
-  if( pTerm
-      && (pTerm->flags & TERM_CODED)==0
-      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
-  ){
-    pTerm->flags |= TERM_CODED;
-    if( pTerm->iParent>=0 ){
-      WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
-      if( (--pOther->nChild)==0 ){
-        disableTerm(pLevel, pOther);
-      }
-    }
-  }
-}
 
+#ifdef SQLITE_ENABLE_FTS3
+/************** Include fts3.h in the middle of main.c ***********************/
+/************** Begin file fts3.h ********************************************/
 /*
-** Apply the affinities associated with the first n columns of index
-** pIdx to the values in the n registers starting at base.
+** 2006 Oct 10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file is used by programs that want to link against the
+** FTS3 library.  All it does is declare the sqlite3Fts3Init() interface.
 */
-static void codeApplyAffinity(Parse *pParse, int base, int n, Index *pIdx){
-  if( n>0 ){
-    Vdbe *v = pParse->pVdbe;
-    assert( v!=0 );
-    sqlite3VdbeAddOp2(v, OP_Affinity, base, n);
-    sqlite3IndexAffinityStr(v, pIdx);
-    sqlite3ExprCacheAffinityChange(pParse, base, n);
-  }
-}
 
+#if 0
+extern "C" {
+#endif  /* __cplusplus */
+
+SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db);
+
+#if 0
+}  /* extern "C" */
+#endif  /* __cplusplus */
 
+/************** End of fts3.h ************************************************/
+/************** Continuing where we left off in main.c ***********************/
+#endif
+#ifdef SQLITE_ENABLE_RTREE
+/************** Include rtree.h in the middle of main.c **********************/
+/************** Begin file rtree.h *******************************************/
 /*
-** Generate code for a single equality term of the WHERE clause.  An equality
-** term can be either X=expr or X IN (...).   pTerm is the term to be 
-** coded.
+** 2008 May 26
 **
-** The current value for the constraint is left in register iReg.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** For a constraint of the form X=expr, the expression is evaluated and its
-** result is left on the stack.  For constraints of the form X IN (...)
-** this routine sets up a loop that will iterate over all values of X.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file is used by programs that want to link against the
+** RTREE library.  All it does is declare the sqlite3RtreeInit() interface.
 */
-static int codeEqualityTerm(
-  Parse *pParse,      /* The parsing context */
-  WhereTerm *pTerm,   /* The term of the WHERE clause to be coded */
-  WhereLevel *pLevel, /* When level of the FROM clause we are working on */
-  int iTarget         /* Attempt to leave results in this register */
-){
-  Expr *pX = pTerm->pExpr;
-  Vdbe *v = pParse->pVdbe;
-  int iReg;                  /* Register holding results */
 
-  if( iTarget<=0 ){
-    iReg = iTarget = sqlite3GetTempReg(pParse);
-  }
-  if( pX->op==TK_EQ ){
-    iReg = sqlite3ExprCodeTarget(pParse, pX->pRight, iTarget);
-  }else if( pX->op==TK_ISNULL ){
-    iReg = iTarget;
-    sqlite3VdbeAddOp2(v, OP_Null, 0, iReg);
-#ifndef SQLITE_OMIT_SUBQUERY
-  }else{
-    int eType;
-    int iTab;
-    struct InLoop *pIn;
+#if 0
+extern "C" {
+#endif  /* __cplusplus */
 
-    assert( pX->op==TK_IN );
-    iReg = iTarget;
-    eType = sqlite3FindInIndex(pParse, pX, 1);
-    iTab = pX->iTable;
-    sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
-    VdbeComment((v, "%.*s", pX->span.n, pX->span.z));
-    if( pLevel->nIn==0 ){
-      pLevel->nxt = sqlite3VdbeMakeLabel(v);
-    }
-    pLevel->nIn++;
-    pLevel->aInLoop = sqlite3DbReallocOrFree(pParse->db, pLevel->aInLoop,
-                                    sizeof(pLevel->aInLoop[0])*pLevel->nIn);
-    pIn = pLevel->aInLoop;
-    if( pIn ){
-      pIn += pLevel->nIn - 1;
-      pIn->iCur = iTab;
-      if( eType==IN_INDEX_ROWID ){
-        pIn->topAddr = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iReg);
-      }else{
-        pIn->topAddr = sqlite3VdbeAddOp3(v, OP_Column, iTab, 0, iReg);
-      }
-      sqlite3VdbeAddOp1(v, OP_IsNull, iReg);
-    }else{
-      pLevel->nIn = 0;
-    }
-#endif
-  }
-  disableTerm(pLevel, pTerm);
-  return iReg;
-}
+SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db);
+
+#if 0
+}  /* extern "C" */
+#endif  /* __cplusplus */
 
+/************** End of rtree.h ***********************************************/
+/************** Continuing where we left off in main.c ***********************/
+#endif
+#ifdef SQLITE_ENABLE_ICU
+/************** Include sqliteicu.h in the middle of main.c ******************/
+/************** Begin file sqliteicu.h ***************************************/
 /*
-** Generate code that will evaluate all == and IN constraints for an
-** index.  The values for all constraints are left on the stack.
+** 2008 May 26
 **
-** For example, consider table t1(a,b,c,d,e,f) with index i1(a,b,c).
-** Suppose the WHERE clause is this:  a==5 AND b IN (1,2,3) AND c>5 AND c<10
-** The index has as many as three equality constraints, but in this
-** example, the third "c" value is an inequality.  So only two 
-** constraints are coded.  This routine will generate code to evaluate
-** a==5 and b IN (1,2,3).  The current values for a and b will be left
-** on the stack - a is the deepest and b the shallowest.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** In the example above nEq==2.  But this subroutine works for any value
-** of nEq including 0.  If nEq==0, this routine is nearly a no-op.
-** The only thing it does is allocate the pLevel->iMem memory cell.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** This routine always allocates at least one memory cell and puts
-** the address of that memory cell in pLevel->iMem.  The code that
-** calls this routine will use pLevel->iMem to store the termination
-** key value of the loop.  If one or more IN operators appear, then
-** this routine allocates an additional nEq memory cells for internal
-** use.
+******************************************************************************
+**
+** This header file is used by programs that want to link against the
+** ICU extension.  All it does is declare the sqlite3IcuInit() interface.
 */
-static int codeAllEqualityTerms(
-  Parse *pParse,        /* Parsing context */
-  WhereLevel *pLevel,   /* Which nested loop of the FROM we are coding */
-  WhereClause *pWC,     /* The WHERE clause */
-  Bitmask notReady,     /* Which parts of FROM have not yet been coded */
-  int nExtraReg         /* Number of extra registers to allocate */
-){
-  int nEq = pLevel->nEq;        /* The number of == or IN constraints to code */
-  Vdbe *v = pParse->pVdbe;      /* The virtual machine under construction */
-  Index *pIdx = pLevel->pIdx;   /* The index being used for this loop */
-  int iCur = pLevel->iTabCur;   /* The cursor of the table */
-  WhereTerm *pTerm;             /* A single constraint term */
-  int j;                        /* Loop counter */
-  int regBase;                  /* Base register */
 
-  /* Figure out how many memory cells we will need then allocate them.
-  ** We always need at least one used to store the loop terminator
-  ** value.  If there are IN operators we'll need one for each == or
-  ** IN constraint.
-  */
-  pLevel->iMem = pParse->nMem + 1;
-  regBase = pParse->nMem + 2;
-  pParse->nMem += pLevel->nEq + 2 + nExtraReg;
+#if 0
+extern "C" {
+#endif  /* __cplusplus */
 
-  /* Evaluate the equality constraints
-  */
-  assert( pIdx->nColumn>=nEq );
-  for(j=0; j<nEq; j++){
-    int r1;
-    int k = pIdx->aiColumn[j];
-    pTerm = findTerm(pWC, iCur, k, notReady, pLevel->flags, pIdx);
-    if( pTerm==0 ) break;
-    assert( (pTerm->flags & TERM_CODED)==0 );
-    r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
-    if( r1!=regBase+j ){
-      sqlite3VdbeAddOp2(v, OP_SCopy, r1, regBase+j);
-    }
-    testcase( pTerm->eOperator & WO_ISNULL );
-    testcase( pTerm->eOperator & WO_IN );
-    if( (pTerm->eOperator & (WO_ISNULL|WO_IN))==0 ){
-      sqlite3VdbeAddOp2(v, OP_IsNull, regBase+j, pLevel->brk);
-    }
-  }
-  return regBase;
-}
+SQLITE_PRIVATE int sqlite3IcuInit(sqlite3 *db);
 
-#if defined(SQLITE_TEST)
+#if 0
+}  /* extern "C" */
+#endif  /* __cplusplus */
+
+
+/************** End of sqliteicu.h *******************************************/
+/************** Continuing where we left off in main.c ***********************/
+#endif
+
+/*
+** The version of the library
+*/
+#ifndef SQLITE_AMALGAMATION
+SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
+#endif
+SQLITE_API const char *sqlite3_libversion(void){ return sqlite3_version; }
+SQLITE_API const char *sqlite3_sourceid(void){ return SQLITE_SOURCE_ID; }
+SQLITE_API int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
+SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
+
+#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
 /*
-** The following variable holds a text description of query plan generated
-** by the most recent call to sqlite3WhereBegin().  Each call to WhereBegin
-** overwrites the previous.  This information is used for testing and
-** analysis only.
+** If the following function pointer is not NULL and if
+** SQLITE_ENABLE_IOTRACE is enabled, then messages describing
+** I/O active are written using this function.  These messages
+** are intended for debugging activity only.
 */
-SQLITE_API char sqlite3_query_plan[BMS*2*40];  /* Text of the join */
-static int nQPlan = 0;              /* Next free slow in _query_plan[] */
-
-#endif /* SQLITE_TEST */
-
+SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*, ...) = 0;
+#endif
 
 /*
-** Free a WhereInfo structure
+** If the following global variable points to a string which is the
+** name of a directory, then that directory will be used to store
+** temporary files.
+**
+** See also the "PRAGMA temp_store_directory" SQL command.
 */
-static void whereInfoFree(WhereInfo *pWInfo){
-  if( pWInfo ){
-    int i;
-    for(i=0; i<pWInfo->nLevel; i++){
-      sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
-      if( pInfo ){
-        assert( pInfo->needToFreeIdxStr==0 );
-        sqlite3_free(pInfo);
-      }
-    }
-    sqlite3_free(pWInfo);
-  }
-}
-
+SQLITE_API char *sqlite3_temp_directory = 0;
 
 /*
-** Generate the beginning of the loop used for WHERE clause processing.
-** The return value is a pointer to an opaque structure that contains
-** information needed to terminate the loop.  Later, the calling routine
-** should invoke sqlite3WhereEnd() with the return value of this function
-** in order to complete the WHERE clause processing.
-**
-** If an error occurs, this routine returns NULL.
-**
-** The basic idea is to do a nested loop, one loop for each table in
-** the FROM clause of a select.  (INSERT and UPDATE statements are the
-** same as a SELECT with only a single table in the FROM clause.)  For
-** example, if the SQL is this:
-**
-**       SELECT * FROM t1, t2, t3 WHERE ...;
-**
-** Then the code generated is conceptually like the following:
-**
-**      foreach row1 in t1 do       \    Code generated
-**        foreach row2 in t2 do      |-- by sqlite3WhereBegin()
-**          foreach row3 in t3 do   /
-**            ...
-**          end                     \    Code generated
-**        end                        |-- by sqlite3WhereEnd()
-**      end                         /
-**
-** Note that the loops might not be nested in the order in which they
-** appear in the FROM clause if a different order is better able to make
-** use of indices.  Note also that when the IN operator appears in
-** the WHERE clause, it might result in additional nested loops for
-** scanning through all values on the right-hand side of the IN.
-**
-** There are Btree cursors associated with each table.  t1 uses cursor
-** number pTabList->a[0].iCursor.  t2 uses the cursor pTabList->a[1].iCursor.
-** And so forth.  This routine generates code to open those VDBE cursors
-** and sqlite3WhereEnd() generates the code to close them.
-**
-** The code that sqlite3WhereBegin() generates leaves the cursors named
-** in pTabList pointing at their appropriate entries.  The [...] code
-** can use OP_Column and OP_Rowid opcodes on these cursors to extract
-** data from the various tables of the loop.
-**
-** If the WHERE clause is empty, the foreach loops must each scan their
-** entire tables.  Thus a three-way join is an O(N^3) operation.  But if
-** the tables have indices and there are terms in the WHERE clause that
-** refer to those indices, a complete table scan can be avoided and the
-** code will run much faster.  Most of the work of this routine is checking
-** to see if there are indices that can be used to speed up the loop.
-**
-** Terms of the WHERE clause are also used to limit which rows actually
-** make it to the "..." in the middle of the loop.  After each "foreach",
-** terms of the WHERE clause that use only terms in that loop and outer
-** loops are evaluated and if false a jump is made around all subsequent
-** inner loops (or around the "..." if the test occurs within the inner-
-** most loop)
+** Initialize SQLite.  
 **
-** OUTER JOINS
+** This routine must be called to initialize the memory allocation,
+** VFS, and mutex subsystems prior to doing any serious work with
+** SQLite.  But as long as you do not compile with SQLITE_OMIT_AUTOINIT
+** this routine will be called automatically by key routines such as
+** sqlite3_open().  
 **
-** An outer join of tables t1 and t2 is conceptally coded as follows:
+** This routine is a no-op except on its very first call for the process,
+** or for the first call after a call to sqlite3_shutdown.
 **
-**    foreach row1 in t1 do
-**      flag = 0
-**      foreach row2 in t2 do
-**        start:
-**          ...
-**          flag = 1
-**      end
-**      if flag==0 then
-**        move the row2 cursor to a null row
-**        goto start
-**      fi
-**    end
+** The first thread to call this routine runs the initialization to
+** completion.  If subsequent threads call this routine before the first
+** thread has finished the initialization process, then the subsequent
+** threads must block until the first thread finishes with the initialization.
 **
-** ORDER BY CLAUSE PROCESSING
+** The first thread might call this routine recursively.  Recursive
+** calls to this routine should not block, of course.  Otherwise the
+** initialization process would never complete.
 **
-** *ppOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
-** if there is one.  If there is no ORDER BY clause or if this routine
-** is called from an UPDATE or DELETE statement, then ppOrderBy is NULL.
+** Let X be the first thread to enter this routine.  Let Y be some other
+** thread.  Then while the initial invocation of this routine by X is
+** incomplete, it is required that:
 **
-** If an index can be used so that the natural output order of the table
-** scan is correct for the ORDER BY clause, then that index is used and
-** *ppOrderBy is set to NULL.  This is an optimization that prevents an
-** unnecessary sort of the result set if an index appropriate for the
-** ORDER BY clause already exists.
+**    *  Calls to this routine from Y must block until the outer-most
+**       call by X completes.
 **
-** If the where clause loops cannot be arranged to provide the correct
-** output order, then the *ppOrderBy is unchanged.
+**    *  Recursive calls to this routine from thread X return immediately
+**       without blocking.
 */
-SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
-  Parse *pParse,        /* The parser context */
-  SrcList *pTabList,    /* A list of all tables to be scanned */
-  Expr *pWhere,         /* The WHERE clause */
-  ExprList **ppOrderBy, /* An ORDER BY clause, or NULL */
-  u8 wflags             /* One of the WHERE_* flags defined in sqliteInt.h */
-){
-  int i;                     /* Loop counter */
-  WhereInfo *pWInfo;         /* Will become the return value of this function */
-  Vdbe *v = pParse->pVdbe;   /* The virtual database engine */
-  int brk, cont = 0;         /* Addresses used during code generation */
-  Bitmask notReady;          /* Cursors that are not yet positioned */
-  WhereTerm *pTerm;          /* A single term in the WHERE clause */
-  ExprMaskSet maskSet;       /* The expression mask set */
-  WhereClause wc;            /* The WHERE clause is divided into these terms */
-  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
-  WhereLevel *pLevel;             /* A single level in the pWInfo list */
-  int iFrom;                      /* First unused FROM clause element */
-  int andFlags;              /* AND-ed combination of all wc.a[].flags */
-  sqlite3 *db;               /* Database connection */
-  ExprList *pOrderBy = 0;
-
-  /* The number of tables in the FROM clause is limited by the number of
-  ** bits in a Bitmask 
-  */
-  if( pTabList->nSrc>BMS ){
-    sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
-    return 0;
-  }
+SQLITE_API int sqlite3_initialize(void){
+  sqlite3_mutex *pMaster;                      /* The main static mutex */
+  int rc;                                      /* Result code */
 
-  if( ppOrderBy ){
-    pOrderBy = *ppOrderBy;
+#ifdef SQLITE_OMIT_WSD
+  rc = sqlite3_wsd_init(4096, 24);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
+#endif
 
-  /* Split the WHERE clause into separate subexpressions where each
-  ** subexpression is separated by an AND operator.
-  */
-  initMaskSet(&maskSet);
-  whereClauseInit(&wc, pParse, &maskSet);
-  sqlite3ExprCodeConstants(pParse, pWhere);
-  whereSplit(&wc, pWhere, TK_AND);
-    
-  /* Allocate and initialize the WhereInfo structure that will become the
-  ** return value.
+  /* If SQLite is already completely initialized, then this call
+  ** to sqlite3_initialize() should be a no-op.  But the initialization
+  ** must be complete.  So isInit must not be set until the very end
+  ** of this routine.
   */
-  db = pParse->db;
-  pWInfo = sqlite3DbMallocZero(db,  
-                      sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
-  if( db->mallocFailed ){
-    goto whereBeginNoMem;
-  }
-  pWInfo->nLevel = pTabList->nSrc;
-  pWInfo->pParse = pParse;
-  pWInfo->pTabList = pTabList;
-  pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
+  if( sqlite3GlobalConfig.isInit ) return SQLITE_OK;
 
-  /* Special case: a WHERE clause that is constant.  Evaluate the
-  ** expression and either jump over all of the code or fall thru.
+  /* Make sure the mutex subsystem is initialized.  If unable to 
+  ** initialize the mutex subsystem, return early with the error.
+  ** If the system is so sick that we are unable to allocate a mutex,
+  ** there is not much SQLite is going to be able to do.
+  **
+  ** The mutex subsystem must take care of serializing its own
+  ** initialization.
   */
-  if( pWhere && (pTabList->nSrc==0 || sqlite3ExprIsConstantNotJoin(pWhere)) ){
-    sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, SQLITE_JUMPIFNULL);
-    pWhere = 0;
-  }
+  rc = sqlite3MutexInit();
+  if( rc ) return rc;
 
-  /* Assign a bit from the bitmask to every term in the FROM clause.
-  **
-  ** When assigning bitmask values to FROM clause cursors, it must be
-  ** the case that if X is the bitmask for the N-th FROM clause term then
-  ** the bitmask for all FROM clause terms to the left of the N-th term
-  ** is (X-1).   An expression from the ON clause of a LEFT JOIN can use
-  ** its Expr.iRightJoinTable value to find the bitmask of the right table
-  ** of the join.  Subtracting one from the right table bitmask gives a
-  ** bitmask for all tables to the left of the join.  Knowing the bitmask
-  ** for all tables to the left of a left join is important.  Ticket #3015.
+  /* Initialize the malloc() system and the recursive pInitMutex mutex.
+  ** This operation is protected by the STATIC_MASTER mutex.  Note that
+  ** MutexAlloc() is called for a static mutex prior to initializing the
+  ** malloc subsystem - this implies that the allocation of a static
+  ** mutex must not require support from the malloc subsystem.
   */
-  for(i=0; i<pTabList->nSrc; i++){
-    createMask(&maskSet, pTabList->a[i].iCursor);
+  pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+  sqlite3_mutex_enter(pMaster);
+  sqlite3GlobalConfig.isMutexInit = 1;
+  if( !sqlite3GlobalConfig.isMallocInit ){
+    rc = sqlite3MallocInit();
   }
-#ifndef NDEBUG
-  {
-    Bitmask toTheLeft = 0;
-    for(i=0; i<pTabList->nSrc; i++){
-      Bitmask m = getMask(&maskSet, pTabList->a[i].iCursor);
-      assert( (m-1)==toTheLeft );
-      toTheLeft |= m;
+  if( rc==SQLITE_OK ){
+    sqlite3GlobalConfig.isMallocInit = 1;
+    if( !sqlite3GlobalConfig.pInitMutex ){
+      sqlite3GlobalConfig.pInitMutex =
+           sqlite3MutexAlloc(SQLITE_MUTEX_RECURSIVE);
+      if( sqlite3GlobalConfig.bCoreMutex && !sqlite3GlobalConfig.pInitMutex ){
+        rc = SQLITE_NOMEM;
+      }
     }
   }
-#endif
+  if( rc==SQLITE_OK ){
+    sqlite3GlobalConfig.nRefInitMutex++;
+  }
+  sqlite3_mutex_leave(pMaster);
 
-  /* Analyze all of the subexpressions.  Note that exprAnalyze() might
-  ** add new virtual terms onto the end of the WHERE clause.  We do not
-  ** want to analyze these virtual terms, so start analyzing at the end
-  ** and work forward so that the added virtual terms are never processed.
-  */
-  exprAnalyzeAll(pTabList, &wc);
-  if( db->mallocFailed ){
-    goto whereBeginNoMem;
+  /* If rc is not SQLITE_OK at this point, then either the malloc
+  ** subsystem could not be initialized or the system failed to allocate
+  ** the pInitMutex mutex. Return an error in either case.  */
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
 
-  /* Chose the best index to use for each table in the FROM clause.
-  **
-  ** This loop fills in the following fields:
-  **
-  **   pWInfo->a[].pIdx      The index to use for this level of the loop.
-  **   pWInfo->a[].flags     WHERE_xxx flags associated with pIdx
-  **   pWInfo->a[].nEq       The number of == and IN constraints
-  **   pWInfo->a[].iFrom     When term of the FROM clause is being coded
-  **   pWInfo->a[].iTabCur   The VDBE cursor for the database table
-  **   pWInfo->a[].iIdxCur   The VDBE cursor for the index
-  **
-  ** This loop also figures out the nesting order of tables in the FROM
-  ** clause.
+  /* Do the rest of the initialization under the recursive mutex so
+  ** that we will be able to handle recursive calls into
+  ** sqlite3_initialize().  The recursive calls normally come through
+  ** sqlite3_os_init() when it invokes sqlite3_vfs_register(), but other
+  ** recursive calls might also be possible.
   */
-  notReady = ~(Bitmask)0;
-  pTabItem = pTabList->a;
-  pLevel = pWInfo->a;
-  andFlags = ~0;
-  WHERETRACE(("*** Optimizer Start ***\n"));
-  for(i=iFrom=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
-    Index *pIdx;                /* Index for FROM table at pTabItem */
-    int flags;                  /* Flags asssociated with pIdx */
-    int nEq;                    /* Number of == or IN constraints */
-    double cost;                /* The cost for pIdx */
-    int j;                      /* For looping over FROM tables */
-    Index *pBest = 0;           /* The best index seen so far */
-    int bestFlags = 0;          /* Flags associated with pBest */
-    int bestNEq = 0;            /* nEq associated with pBest */
-    double lowestCost;          /* Cost of the pBest */
-    int bestJ = 0;              /* The value of j */
-    Bitmask m;                  /* Bitmask value for j or bestJ */
-    int once = 0;               /* True when first table is seen */
-    sqlite3_index_info *pIndex; /* Current virtual index */
-
-    lowestCost = SQLITE_BIG_DBL;
-    for(j=iFrom, pTabItem=&pTabList->a[j]; j<pTabList->nSrc; j++, pTabItem++){
-      int doNotReorder;  /* True if this table should not be reordered */
-
-      doNotReorder =  (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0;
-      if( once && doNotReorder ) break;
-      m = getMask(&maskSet, pTabItem->iCursor);
-      if( (m & notReady)==0 ){
-        if( j==iFrom ) iFrom++;
-        continue;
-      }
-      assert( pTabItem->pTab );
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      if( IsVirtual(pTabItem->pTab) ){
-        sqlite3_index_info **ppIdxInfo = &pWInfo->a[j].pIdxInfo;
-        cost = bestVirtualIndex(pParse, &wc, pTabItem, notReady,
-                                ppOrderBy ? *ppOrderBy : 0, i==0,
-                                ppIdxInfo);
-        flags = WHERE_VIRTUALTABLE;
-        pIndex = *ppIdxInfo;
-        if( pIndex && pIndex->orderByConsumed ){
-          flags = WHERE_VIRTUALTABLE | WHERE_ORDERBY;
-        }
-        pIdx = 0;
-        nEq = 0;
-        if( (SQLITE_BIG_DBL/2.0)<cost ){
-          /* The cost is not allowed to be larger than SQLITE_BIG_DBL (the
-          ** inital value of lowestCost in this loop. If it is, then
-          ** the (cost<lowestCost) test below will never be true and
-          ** pLevel->pBestIdx never set.
-          */ 
-          cost = (SQLITE_BIG_DBL/2.0);
-        }
-      }else 
-#endif
-      {
-        cost = bestIndex(pParse, &wc, pTabItem, notReady,
-                         (i==0 && ppOrderBy) ? *ppOrderBy : 0,
-                         &pIdx, &flags, &nEq);
-        pIndex = 0;
-      }
-      if( cost<lowestCost ){
-        once = 1;
-        lowestCost = cost;
-        pBest = pIdx;
-        bestFlags = flags;
-        bestNEq = nEq;
-        bestJ = j;
-        pLevel->pBestIdx = pIndex;
-      }
-      if( doNotReorder ) break;
-    }
-    WHERETRACE(("*** Optimizer choose table %d for loop %d\n", bestJ,
-           pLevel-pWInfo->a));
-    if( (bestFlags & WHERE_ORDERBY)!=0 ){
-      *ppOrderBy = 0;
+  sqlite3_mutex_enter(sqlite3GlobalConfig.pInitMutex);
+  if( sqlite3GlobalConfig.isInit==0 && sqlite3GlobalConfig.inProgress==0 ){
+    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+    sqlite3GlobalConfig.inProgress = 1;
+    memset(pHash, 0, sizeof(sqlite3GlobalFunctions));
+    sqlite3RegisterGlobalFunctions();
+    if( sqlite3GlobalConfig.isPCacheInit==0 ){
+      rc = sqlite3PcacheInitialize();
     }
-    andFlags &= bestFlags;
-    pLevel->flags = bestFlags;
-    pLevel->pIdx = pBest;
-    pLevel->nEq = bestNEq;
-    pLevel->aInLoop = 0;
-    pLevel->nIn = 0;
-    if( pBest ){
-      pLevel->iIdxCur = pParse->nTab++;
-    }else{
-      pLevel->iIdxCur = -1;
+    if( rc==SQLITE_OK ){
+      sqlite3GlobalConfig.isPCacheInit = 1;
+      rc = sqlite3OsInit();
+    }
+    if( rc==SQLITE_OK ){
+      sqlite3PCacheBufferSetup( sqlite3GlobalConfig.pPage, 
+          sqlite3GlobalConfig.szPage, sqlite3GlobalConfig.nPage);
+      sqlite3GlobalConfig.isInit = 1;
     }
-    notReady &= ~getMask(&maskSet, pTabList->a[bestJ].iCursor);
-    pLevel->iFrom = bestJ;
+    sqlite3GlobalConfig.inProgress = 0;
   }
-  WHERETRACE(("*** Optimizer Finished ***\n"));
+  sqlite3_mutex_leave(sqlite3GlobalConfig.pInitMutex);
 
-  /* If the total query only selects a single row, then the ORDER BY
-  ** clause is irrelevant.
+  /* Go back under the static mutex and clean up the recursive
+  ** mutex to prevent a resource leak.
   */
-  if( (andFlags & WHERE_UNIQUE)!=0 && ppOrderBy ){
-    *ppOrderBy = 0;
+  sqlite3_mutex_enter(pMaster);
+  sqlite3GlobalConfig.nRefInitMutex--;
+  if( sqlite3GlobalConfig.nRefInitMutex<=0 ){
+    assert( sqlite3GlobalConfig.nRefInitMutex==0 );
+    sqlite3_mutex_free(sqlite3GlobalConfig.pInitMutex);
+    sqlite3GlobalConfig.pInitMutex = 0;
   }
+  sqlite3_mutex_leave(pMaster);
 
-  /* If the caller is an UPDATE or DELETE statement that is requesting
-  ** to use a one-pass algorithm, determine if this is appropriate.
-  ** The one-pass algorithm only works if the WHERE clause constraints
-  ** the statement to update a single row.
+  /* The following is just a sanity check to make sure SQLite has
+  ** been compiled correctly.  It is important to run this code, but
+  ** we don't want to run it too often and soak up CPU cycles for no
+  ** reason.  So we run it once during initialization.
   */
-  assert( (wflags & WHERE_ONEPASS_DESIRED)==0 || pWInfo->nLevel==1 );
-  if( (wflags & WHERE_ONEPASS_DESIRED)!=0 && (andFlags & WHERE_UNIQUE)!=0 ){
-    pWInfo->okOnePass = 1;
-    pWInfo->a[0].flags &= ~WHERE_IDX_ONLY;
+#ifndef NDEBUG
+#ifndef SQLITE_OMIT_FLOATING_POINT
+  /* This section of code's only "output" is via assert() statements. */
+  if ( rc==SQLITE_OK ){
+    u64 x = (((u64)1)<<63)-1;
+    double y;
+    assert(sizeof(x)==8);
+    assert(sizeof(x)==sizeof(y));
+    memcpy(&y, &x, 8);
+    assert( sqlite3IsNaN(y) );
   }
+#endif
+#endif
 
-  /* Open all tables in the pTabList and any indices selected for
-  ** searching those tables.
-  */
-  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
-  for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
-    Table *pTab;     /* Table to open */
-    Index *pIx;      /* Index used to access pTab (if any) */
-    int iDb;         /* Index of database containing table/index */
-    int iIdxCur = pLevel->iIdxCur;
+  return rc;
+}
 
-#ifndef SQLITE_OMIT_EXPLAIN
-    if( pParse->explain==2 ){
-      char *zMsg;
-      struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
-      zMsg = sqlite3MPrintf(db, "TABLE %s", pItem->zName);
-      if( pItem->zAlias ){
-        zMsg = sqlite3MPrintf(db, "%z AS %s", zMsg, pItem->zAlias);
-      }
-      if( (pIx = pLevel->pIdx)!=0 ){
-        zMsg = sqlite3MPrintf(db, "%z WITH INDEX %s", zMsg, pIx->zName);
-      }else if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
-        zMsg = sqlite3MPrintf(db, "%z USING PRIMARY KEY", zMsg);
-      }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      else if( pLevel->pBestIdx ){
-        sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
-        zMsg = sqlite3MPrintf(db, "%z VIRTUAL TABLE INDEX %d:%s", zMsg,
-                    pBestIdx->idxNum, pBestIdx->idxStr);
-      }
+/*
+** Undo the effects of sqlite3_initialize().  Must not be called while
+** there are outstanding database connections or memory allocations or
+** while any part of SQLite is otherwise in use in any thread.  This
+** routine is not threadsafe.  But it is safe to invoke this routine
+** on when SQLite is already shut down.  If SQLite is already shut down
+** when this routine is invoked, then this routine is a harmless no-op.
+*/
+SQLITE_API int sqlite3_shutdown(void){
+  if( sqlite3GlobalConfig.isInit ){
+    sqlite3_os_end();
+    sqlite3_reset_auto_extension();
+    sqlite3GlobalConfig.isInit = 0;
+  }
+  if( sqlite3GlobalConfig.isPCacheInit ){
+    sqlite3PcacheShutdown();
+    sqlite3GlobalConfig.isPCacheInit = 0;
+  }
+  if( sqlite3GlobalConfig.isMallocInit ){
+    sqlite3MallocEnd();
+    sqlite3GlobalConfig.isMallocInit = 0;
+  }
+  if( sqlite3GlobalConfig.isMutexInit ){
+    sqlite3MutexEnd();
+    sqlite3GlobalConfig.isMutexInit = 0;
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** This API allows applications to modify the global configuration of
+** the SQLite library at run-time.
+**
+** This routine should only be called when there are no outstanding
+** database connections or memory allocations.  This routine is not
+** threadsafe.  Failure to heed these warnings can lead to unpredictable
+** behavior.
+*/
+SQLITE_API int sqlite3_config(int op, ...){
+  va_list ap;
+  int rc = SQLITE_OK;
+
+  /* sqlite3_config() shall return SQLITE_MISUSE if it is invoked while
+  ** the SQLite library is in use. */
+  if( sqlite3GlobalConfig.isInit ) return SQLITE_MISUSE;
+
+  va_start(ap, op);
+  switch( op ){
+
+    /* Mutex configuration options are only available in a threadsafe
+    ** compile. 
+    */
+#if SQLITE_THREADSAFE
+    case SQLITE_CONFIG_SINGLETHREAD: {
+      /* Disable all mutexing */
+      sqlite3GlobalConfig.bCoreMutex = 0;
+      sqlite3GlobalConfig.bFullMutex = 0;
+      break;
+    }
+    case SQLITE_CONFIG_MULTITHREAD: {
+      /* Disable mutexing of database connections */
+      /* Enable mutexing of core data structures */
+      sqlite3GlobalConfig.bCoreMutex = 1;
+      sqlite3GlobalConfig.bFullMutex = 0;
+      break;
+    }
+    case SQLITE_CONFIG_SERIALIZED: {
+      /* Enable all mutexing */
+      sqlite3GlobalConfig.bCoreMutex = 1;
+      sqlite3GlobalConfig.bFullMutex = 1;
+      break;
+    }
+    case SQLITE_CONFIG_MUTEX: {
+      /* Specify an alternative mutex implementation */
+      sqlite3GlobalConfig.mutex = *va_arg(ap, sqlite3_mutex_methods*);
+      break;
+    }
+    case SQLITE_CONFIG_GETMUTEX: {
+      /* Retrieve the current mutex implementation */
+      *va_arg(ap, sqlite3_mutex_methods*) = sqlite3GlobalConfig.mutex;
+      break;
+    }
 #endif
-      if( pLevel->flags & WHERE_ORDERBY ){
-        zMsg = sqlite3MPrintf(db, "%z ORDER BY", zMsg);
+
+
+    case SQLITE_CONFIG_MALLOC: {
+      /* Specify an alternative malloc implementation */
+      sqlite3GlobalConfig.m = *va_arg(ap, sqlite3_mem_methods*);
+      break;
+    }
+    case SQLITE_CONFIG_GETMALLOC: {
+      /* Retrieve the current malloc() implementation */
+      if( sqlite3GlobalConfig.m.xMalloc==0 ) sqlite3MemSetDefault();
+      *va_arg(ap, sqlite3_mem_methods*) = sqlite3GlobalConfig.m;
+      break;
+    }
+    case SQLITE_CONFIG_MEMSTATUS: {
+      /* Enable or disable the malloc status collection */
+      sqlite3GlobalConfig.bMemstat = va_arg(ap, int);
+      break;
+    }
+    case SQLITE_CONFIG_SCRATCH: {
+      /* Designate a buffer for scratch memory space */
+      sqlite3GlobalConfig.pScratch = va_arg(ap, void*);
+      sqlite3GlobalConfig.szScratch = va_arg(ap, int);
+      sqlite3GlobalConfig.nScratch = va_arg(ap, int);
+      break;
+    }
+    case SQLITE_CONFIG_PAGECACHE: {
+      /* Designate a buffer for page cache memory space */
+      sqlite3GlobalConfig.pPage = va_arg(ap, void*);
+      sqlite3GlobalConfig.szPage = va_arg(ap, int);
+      sqlite3GlobalConfig.nPage = va_arg(ap, int);
+      break;
+    }
+
+    case SQLITE_CONFIG_PCACHE: {
+      /* Specify an alternative page cache implementation */
+      sqlite3GlobalConfig.pcache = *va_arg(ap, sqlite3_pcache_methods*);
+      break;
+    }
+
+    case SQLITE_CONFIG_GETPCACHE: {
+      if( sqlite3GlobalConfig.pcache.xInit==0 ){
+        sqlite3PCacheSetDefault();
       }
-      sqlite3VdbeAddOp4(v, OP_Explain, i, pLevel->iFrom, 0, zMsg, P4_DYNAMIC);
+      *va_arg(ap, sqlite3_pcache_methods*) = sqlite3GlobalConfig.pcache;
+      break;
     }
-#endif /* SQLITE_OMIT_EXPLAIN */
-    pTabItem = &pTabList->a[pLevel->iFrom];
-    pTab = pTabItem->pTab;
-    iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-    if( pTab->isEphem || pTab->pSelect ) continue;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( pLevel->pBestIdx ){
-      int iCur = pTabItem->iCursor;
-      sqlite3VdbeAddOp4(v, OP_VOpen, iCur, 0, 0,
-                        (const char*)pTab->pVtab, P4_VTAB);
-    }else
+
+#if defined(SQLITE_ENABLE_MEMSYS3) || defined(SQLITE_ENABLE_MEMSYS5)
+    case SQLITE_CONFIG_HEAP: {
+      /* Designate a buffer for heap memory space */
+      sqlite3GlobalConfig.pHeap = va_arg(ap, void*);
+      sqlite3GlobalConfig.nHeap = va_arg(ap, int);
+      sqlite3GlobalConfig.mnReq = va_arg(ap, int);
+
+      if( sqlite3GlobalConfig.pHeap==0 ){
+        /* If the heap pointer is NULL, then restore the malloc implementation
+        ** back to NULL pointers too.  This will cause the malloc to go
+        ** back to its default implementation when sqlite3_initialize() is
+        ** run.
+        */
+        memset(&sqlite3GlobalConfig.m, 0, sizeof(sqlite3GlobalConfig.m));
+      }else{
+        /* The heap pointer is not NULL, then install one of the
+        ** mem5.c/mem3.c methods. If neither ENABLE_MEMSYS3 nor
+        ** ENABLE_MEMSYS5 is defined, return an error.
+        */
+#ifdef SQLITE_ENABLE_MEMSYS3
+        sqlite3GlobalConfig.m = *sqlite3MemGetMemsys3();
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS5
+        sqlite3GlobalConfig.m = *sqlite3MemGetMemsys5();
 #endif
-    if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
-      int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
-      sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
-      if( !pWInfo->okOnePass && pTab->nCol<(sizeof(Bitmask)*8) ){
-        Bitmask b = pTabItem->colUsed;
-        int n = 0;
-        for(; b; b=b>>1, n++){}
-        sqlite3VdbeChangeP2(v, sqlite3VdbeCurrentAddr(v)-2, n);
-        assert( n<=pTab->nCol );
       }
-    }else{
-      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
+      break;
     }
-    pLevel->iTabCur = pTabItem->iCursor;
-    if( (pIx = pLevel->pIdx)!=0 ){
-      KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
-      assert( pIx->pSchema==pTab->pSchema );
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIx->nColumn+1);
-      sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
-                        (char*)pKey, P4_KEYINFO_HANDOFF);
-      VdbeComment((v, "%s", pIx->zName));
+#endif
+
+    case SQLITE_CONFIG_LOOKASIDE: {
+      sqlite3GlobalConfig.szLookaside = va_arg(ap, int);
+      sqlite3GlobalConfig.nLookaside = va_arg(ap, int);
+      break;
+    }
+
+    default: {
+      rc = SQLITE_ERROR;
+      break;
     }
-    sqlite3CodeVerifySchema(pParse, iDb);
   }
-  pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
+  va_end(ap);
+  return rc;
+}
 
-  /* Generate the code to do the search.  Each iteration of the for
-  ** loop below generates code for a single nested loop of the VM
-  ** program.
-  */
-  notReady = ~(Bitmask)0;
-  for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
-    int j;
-    int iCur = pTabItem->iCursor;  /* The VDBE cursor for the table */
-    Index *pIdx;       /* The index we will be using */
-    int nxt;           /* Where to jump to continue with the next IN case */
-    int iIdxCur;       /* The VDBE cursor for the index */
-    int omitTable;     /* True if we use the index only */
-    int bRev;          /* True if we need to scan in reverse order */
+/*
+** Set up the lookaside buffers for a database connection.
+** Return SQLITE_OK on success.  
+** If lookaside is already active, return SQLITE_BUSY.
+**
+** The sz parameter is the number of bytes in each lookaside slot.
+** The cnt parameter is the number of slots.  If pStart is NULL the
+** space for the lookaside memory is obtained from sqlite3_malloc().
+** If pStart is not NULL then it is sz*cnt bytes of memory to use for
+** the lookaside memory.
+*/
+static int setupLookaside(sqlite3 *db, void *pBuf, int sz, int cnt){
+  void *pStart;
+  if( db->lookaside.nOut ){
+    return SQLITE_BUSY;
+  }
+  /* Free any existing lookaside buffer for this handle before
+  ** allocating a new one so we don't have to have space for 
+  ** both at the same time.
+  */
+  if( db->lookaside.bMalloced ){
+    sqlite3_free(db->lookaside.pStart);
+  }
+  /* The size of a lookaside slot needs to be larger than a pointer
+  ** to be useful.
+  */
+  if( sz<=(int)sizeof(LookasideSlot*) ) sz = 0;
+  if( cnt<0 ) cnt = 0;
+  if( sz==0 || cnt==0 ){
+    sz = 0;
+    pStart = 0;
+  }else if( pBuf==0 ){
+    sz = ROUND8(sz);
+    sqlite3BeginBenignMalloc();
+    pStart = sqlite3Malloc( sz*cnt );
+    sqlite3EndBenignMalloc();
+  }else{
+    sz = ROUNDDOWN8(sz);
+    pStart = pBuf;
+  }
+  db->lookaside.pStart = pStart;
+  db->lookaside.pFree = 0;
+  db->lookaside.sz = (u16)sz;
+  if( pStart ){
+    int i;
+    LookasideSlot *p;
+    assert( sz > (int)sizeof(LookasideSlot*) );
+    p = (LookasideSlot*)pStart;
+    for(i=cnt-1; i>=0; i--){
+      p->pNext = db->lookaside.pFree;
+      db->lookaside.pFree = p;
+      p = (LookasideSlot*)&((u8*)p)[sz];
+    }
+    db->lookaside.pEnd = p;
+    db->lookaside.bEnabled = 1;
+    db->lookaside.bMalloced = pBuf==0 ?1:0;
+  }else{
+    db->lookaside.pEnd = 0;
+    db->lookaside.bEnabled = 0;
+    db->lookaside.bMalloced = 0;
+  }
+  return SQLITE_OK;
+}
 
-    pTabItem = &pTabList->a[pLevel->iFrom];
-    iCur = pTabItem->iCursor;
-    pIdx = pLevel->pIdx;
-    iIdxCur = pLevel->iIdxCur;
-    bRev = (pLevel->flags & WHERE_REVERSE)!=0;
-    omitTable = (pLevel->flags & WHERE_IDX_ONLY)!=0;
+/*
+** Return the mutex associated with a database connection.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3 *db){
+  return db->mutex;
+}
 
-    /* Create labels for the "break" and "continue" instructions
-    ** for the current loop.  Jump to brk to break out of a loop.
-    ** Jump to cont to go immediately to the next iteration of the
-    ** loop.
-    **
-    ** When there is an IN operator, we also have a "nxt" label that
-    ** means to continue with the next IN value combination.  When
-    ** there are no IN operators in the constraints, the "nxt" label
-    ** is the same as "brk".
-    */
-    brk = pLevel->brk = pLevel->nxt = sqlite3VdbeMakeLabel(v);
-    cont = pLevel->cont = sqlite3VdbeMakeLabel(v);
+/*
+** Configuration settings for an individual database connection
+*/
+SQLITE_API int sqlite3_db_config(sqlite3 *db, int op, ...){
+  va_list ap;
+  int rc;
+  va_start(ap, op);
+  switch( op ){
+    case SQLITE_DBCONFIG_LOOKASIDE: {
+      void *pBuf = va_arg(ap, void*);
+      int sz = va_arg(ap, int);
+      int cnt = va_arg(ap, int);
+      rc = setupLookaside(db, pBuf, sz, cnt);
+      break;
+    }
+    default: {
+      rc = SQLITE_ERROR;
+      break;
+    }
+  }
+  va_end(ap);
+  return rc;
+}
 
-    /* If this is the right table of a LEFT OUTER JOIN, allocate and
-    ** initialize a memory cell that records if this table matches any
-    ** row of the left table of the join.
-    */
-    if( pLevel->iFrom>0 && (pTabItem[0].jointype & JT_LEFT)!=0 ){
-      pLevel->iLeftJoin = ++pParse->nMem;
-      sqlite3VdbeAddOp2(v, OP_Integer, 0, pLevel->iLeftJoin);
-      VdbeComment((v, "init LEFT JOIN no-match flag"));
+
+/*
+** Return true if the buffer z[0..n-1] contains all spaces.
+*/
+static int allSpaces(const char *z, int n){
+  while( n>0 && z[n-1]==' ' ){ n--; }
+  return n==0;
+}
+
+/*
+** This is the default collating function named "BINARY" which is always
+** available.
+**
+** If the padFlag argument is not NULL then space padding at the end
+** of strings is ignored.  This implements the RTRIM collation.
+*/
+static int binCollFunc(
+  void *padFlag,
+  int nKey1, const void *pKey1,
+  int nKey2, const void *pKey2
+){
+  int rc, n;
+  n = nKey1<nKey2 ? nKey1 : nKey2;
+  rc = memcmp(pKey1, pKey2, n);
+  if( rc==0 ){
+    if( padFlag
+     && allSpaces(((char*)pKey1)+n, nKey1-n)
+     && allSpaces(((char*)pKey2)+n, nKey2-n)
+    ){
+      /* Leave rc unchanged at 0 */
+    }else{
+      rc = nKey1 - nKey2;
     }
+  }
+  return rc;
+}
 
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( pLevel->pBestIdx ){
-      /* Case 0:  The table is a virtual-table.  Use the VFilter and VNext
-      **          to access the data.
-      */
-      int j;
-      int iReg;   /* P3 Value for OP_VFilter */
-      sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
-      int nConstraint = pBestIdx->nConstraint;
-      struct sqlite3_index_constraint_usage *aUsage =
-                                                  pBestIdx->aConstraintUsage;
-      const struct sqlite3_index_constraint *aConstraint =
-                                                  pBestIdx->aConstraint;
-
-      iReg = sqlite3GetTempRange(pParse, nConstraint+2);
-      for(j=1; j<=nConstraint; j++){
-        int k;
-        for(k=0; k<nConstraint; k++){
-          if( aUsage[k].argvIndex==j ){
-            int iTerm = aConstraint[k].iTermOffset;
-            sqlite3ExprCode(pParse, wc.a[iTerm].pExpr->pRight, iReg+j+1);
-            break;
-          }
-        }
-        if( k==nConstraint ) break;
-      }
-      sqlite3VdbeAddOp2(v, OP_Integer, pBestIdx->idxNum, iReg);
-      sqlite3VdbeAddOp2(v, OP_Integer, j-1, iReg+1);
-      sqlite3VdbeAddOp4(v, OP_VFilter, iCur, brk, iReg, pBestIdx->idxStr,
-                        pBestIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
-      sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
-      pBestIdx->needToFreeIdxStr = 0;
-      for(j=0; j<pBestIdx->nConstraint; j++){
-        if( aUsage[j].omit ){
-          int iTerm = aConstraint[j].iTermOffset;
-          disableTerm(pLevel, &wc.a[iTerm]);
-        }
-      }
-      pLevel->op = OP_VNext;
-      pLevel->p1 = iCur;
-      pLevel->p2 = sqlite3VdbeCurrentAddr(v);
-    }else
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
+/*
+** Another built-in collating sequence: NOCASE. 
+**
+** This collating sequence is intended to be used for "case independant
+** comparison". SQLite's knowledge of upper and lower case equivalents
+** extends only to the 26 characters used in the English language.
+**
+** At the moment there is only a UTF-8 implementation.
+*/
+static int nocaseCollatingFunc(
+  void *NotUsed,
+  int nKey1, const void *pKey1,
+  int nKey2, const void *pKey2
+){
+  int r = sqlite3StrNICmp(
+      (const char *)pKey1, (const char *)pKey2, (nKey1<nKey2)?nKey1:nKey2);
+  UNUSED_PARAMETER(NotUsed);
+  if( 0==r ){
+    r = nKey1-nKey2;
+  }
+  return r;
+}
 
-    if( pLevel->flags & WHERE_ROWID_EQ ){
-      /* Case 1:  We can directly reference a single row using an
-      **          equality comparison against the ROWID field.  Or
-      **          we reference multiple rows using a "rowid IN (...)"
-      **          construct.
-      */
-      int r1;
-      pTerm = findTerm(&wc, iCur, -1, notReady, WO_EQ|WO_IN, 0);
-      assert( pTerm!=0 );
-      assert( pTerm->pExpr!=0 );
-      assert( pTerm->leftCursor==iCur );
-      assert( omitTable==0 );
-      r1 = codeEqualityTerm(pParse, pTerm, pLevel, 0);
-      nxt = pLevel->nxt;
-      sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, nxt);
-      sqlite3VdbeAddOp3(v, OP_NotExists, iCur, nxt, r1);
-      VdbeComment((v, "pk"));
-      pLevel->op = OP_Noop;
-    }else if( pLevel->flags & WHERE_ROWID_RANGE ){
-      /* Case 2:  We have an inequality comparison against the ROWID field.
-      */
-      int testOp = OP_Noop;
-      int start;
-      WhereTerm *pStart, *pEnd;
-
-      assert( omitTable==0 );
-      pStart = findTerm(&wc, iCur, -1, notReady, WO_GT|WO_GE, 0);
-      pEnd = findTerm(&wc, iCur, -1, notReady, WO_LT|WO_LE, 0);
-      if( bRev ){
-        pTerm = pStart;
-        pStart = pEnd;
-        pEnd = pTerm;
-      }
-      if( pStart ){
-        Expr *pX;
-        int r1, regFree1;
-        pX = pStart->pExpr;
-        assert( pX!=0 );
-        assert( pStart->leftCursor==iCur );
-        r1 = sqlite3ExprCodeTemp(pParse, pX->pRight, &regFree1);
-        sqlite3VdbeAddOp3(v, OP_ForceInt, r1, brk, 
-                             pX->op==TK_LE || pX->op==TK_GT);
-        sqlite3VdbeAddOp3(v, bRev ? OP_MoveLt : OP_MoveGe, iCur, brk, r1);
-        VdbeComment((v, "pk"));
-        sqlite3ReleaseTempReg(pParse, regFree1);
-        disableTerm(pLevel, pStart);
-      }else{
-        sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iCur, brk);
-      }
-      if( pEnd ){
-        Expr *pX;
-        pX = pEnd->pExpr;
-        assert( pX!=0 );
-        assert( pEnd->leftCursor==iCur );
-        pLevel->iMem = ++pParse->nMem;
-        sqlite3ExprCode(pParse, pX->pRight, pLevel->iMem);
-        if( pX->op==TK_LT || pX->op==TK_GT ){
-          testOp = bRev ? OP_Le : OP_Ge;
-        }else{
-          testOp = bRev ? OP_Lt : OP_Gt;
-        }
-        disableTerm(pLevel, pEnd);
-      }
-      start = sqlite3VdbeCurrentAddr(v);
-      pLevel->op = bRev ? OP_Prev : OP_Next;
-      pLevel->p1 = iCur;
-      pLevel->p2 = start;
-      if( testOp!=OP_Noop ){
-        int r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp2(v, OP_Rowid, iCur, r1);
-        /* sqlite3VdbeAddOp2(v, OP_SCopy, pLevel->iMem, 0); */
-        sqlite3VdbeAddOp3(v, testOp, pLevel->iMem, brk, r1);
-        sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC | SQLITE_JUMPIFNULL);
-        sqlite3ReleaseTempReg(pParse, r1);
-      }
-    }else if( pLevel->flags & (WHERE_COLUMN_RANGE|WHERE_COLUMN_EQ) ){
-      /* Case 3: A scan using an index.
-      **
-      **         The WHERE clause may contain zero or more equality 
-      **         terms ("==" or "IN" operators) that refer to the N
-      **         left-most columns of the index. It may also contain
-      **         inequality constraints (>, <, >= or <=) on the indexed
-      **         column that immediately follows the N equalities. Only 
-      **         the right-most column can be an inequality - the rest must
-      **         use the "==" and "IN" operators. For example, if the 
-      **         index is on (x,y,z), then the following clauses are all 
-      **         optimized:
-      **
-      **            x=5
-      **            x=5 AND y=10
-      **            x=5 AND y<10
-      **            x=5 AND y>5 AND y<10
-      **            x=5 AND y=5 AND z<=10
-      **
-      **         The z<10 term of the following cannot be used, only
-      **         the x=5 term:
-      **
-      **            x=5 AND z<10
-      **
-      **         N may be zero if there are inequality constraints.
-      **         If there are no inequality constraints, then N is at
-      **         least one.
-      **
-      **         This case is also used when there are no WHERE clause
-      **         constraints but an index is selected anyway, in order
-      **         to force the output order to conform to an ORDER BY.
-      */  
-      int aStartOp[] = {
-        0,
-        0,
-        OP_Rewind,           /* 2: (!start_constraints && startEq &&  !bRev) */
-        OP_Last,             /* 3: (!start_constraints && startEq &&   bRev) */
-        OP_MoveGt,           /* 4: (start_constraints  && !startEq && !bRev) */
-        OP_MoveLt,           /* 5: (start_constraints  && !startEq &&  bRev) */
-        OP_MoveGe,           /* 6: (start_constraints  &&  startEq && !bRev) */
-        OP_MoveLe            /* 7: (start_constraints  &&  startEq &&  bRev) */
-      };
-      int aEndOp[] = {
-        OP_Noop,             /* 0: (!end_constraints) */
-        OP_IdxGE,            /* 1: (end_constraints && !bRev) */
-        OP_IdxLT             /* 2: (end_constraints && bRev) */
-      };
-      int nEq = pLevel->nEq;
-      int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
-      int regBase;                 /* Base register holding constraint values */
-      int r1;                      /* Temp register */
-      WhereTerm *pRangeStart = 0;  /* Inequality constraint at range start */
-      WhereTerm *pRangeEnd = 0;    /* Inequality constraint at range end */
-      int startEq;                 /* True if range start uses ==, >= or <= */
-      int endEq;                   /* True if range end uses ==, >= or <= */
-      int start_constraints;       /* Start of range is constrained */
-      int k = pIdx->aiColumn[nEq]; /* Column for inequality constraints */
-      int nConstraint;             /* Number of constraint terms */
-      int op;
-
-      /* Generate code to evaluate all constraint terms using == or IN
-      ** and store the values of those terms in an array of registers
-      ** starting at regBase.
-      */
-      regBase = codeAllEqualityTerms(pParse, pLevel, &wc, notReady, 2);
-      nxt = pLevel->nxt;
-
-      /* If this loop satisfies a sort order (pOrderBy) request that 
-      ** was passed to this function to implement a "SELECT min(x) ..." 
-      ** query, then the caller will only allow the loop to run for
-      ** a single iteration. This means that the first row returned
-      ** should not have a NULL value stored in 'x'. If column 'x' is
-      ** the first one after the nEq equality constraints in the index,
-      ** this requires some special handling.
-      */
-      if( (wflags&WHERE_ORDERBY_MIN)!=0
-       && (pLevel->flags&WHERE_ORDERBY)
-       && (pIdx->nColumn>nEq)
-       && (pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq])
-      ){
-        isMinQuery = 1;
-      }
+/*
+** Return the ROWID of the most recent insert
+*/
+SQLITE_API sqlite_int64 sqlite3_last_insert_rowid(sqlite3 *db){
+  return db->lastRowid;
+}
+
+/*
+** Return the number of changes in the most recent call to sqlite3_exec().
+*/
+SQLITE_API int sqlite3_changes(sqlite3 *db){
+  return db->nChange;
+}
+
+/*
+** Return the number of changes since the database handle was opened.
+*/
+SQLITE_API int sqlite3_total_changes(sqlite3 *db){
+  return db->nTotalChange;
+}
+
+/*
+** Close all open savepoints. This function only manipulates fields of the
+** database handle object, it does not close any savepoints that may be open
+** at the b-tree/pager level.
+*/
+SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *db){
+  while( db->pSavepoint ){
+    Savepoint *pTmp = db->pSavepoint;
+    db->pSavepoint = pTmp->pNext;
+    sqlite3DbFree(db, pTmp);
+  }
+  db->nSavepoint = 0;
+  db->nStatement = 0;
+  db->isTransactionSavepoint = 0;
+}
+
+/*
+** Close an existing SQLite database
+*/
+SQLITE_API int sqlite3_close(sqlite3 *db){
+  HashElem *i;
+  int j;
 
-      /* Find any inequality constraint terms for the start and end 
-      ** of the range. 
-      */
-      if( pLevel->flags & WHERE_TOP_LIMIT ){
-        pRangeEnd = findTerm(&wc, iCur, k, notReady, (WO_LT|WO_LE), pIdx);
-      }
-      if( pLevel->flags & WHERE_BTM_LIMIT ){
-        pRangeStart = findTerm(&wc, iCur, k, notReady, (WO_GT|WO_GE), pIdx);
-      }
+  if( !db ){
+    return SQLITE_OK;
+  }
+  if( !sqlite3SafetyCheckSickOrOk(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
 
-      /* If we are doing a reverse order scan on an ascending index, or
-      ** a forward order scan on a descending index, interchange the 
-      ** start and end terms (pRangeStart and pRangeEnd).
-      */
-      if( bRev==(pIdx->aSortOrder[nEq]==SQLITE_SO_ASC) ){
-        SWAP(WhereTerm *, pRangeEnd, pRangeStart);
-      }
-
-      testcase( pRangeStart && pRangeStart->eOperator & WO_LE );
-      testcase( pRangeStart && pRangeStart->eOperator & WO_GE );
-      testcase( pRangeEnd && pRangeEnd->eOperator & WO_LE );
-      testcase( pRangeEnd && pRangeEnd->eOperator & WO_GE );
-      startEq = !pRangeStart || pRangeStart->eOperator & (WO_LE|WO_GE);
-      endEq =   !pRangeEnd || pRangeEnd->eOperator & (WO_LE|WO_GE);
-      start_constraints = pRangeStart || nEq>0;
-
-      /* Seek the index cursor to the start of the range. */
-      nConstraint = nEq;
-      if( pRangeStart ){
-        int dcc = pParse->disableColCache;
-        if( pRangeEnd ){
-          pParse->disableColCache = 1;
-        }
-        sqlite3ExprCode(pParse, pRangeStart->pExpr->pRight, regBase+nEq);
-        pParse->disableColCache = dcc;
-        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
-        nConstraint++;
-      }else if( isMinQuery ){
-        sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
-        nConstraint++;
-        startEq = 0;
-        start_constraints = 1;
-      }
-      codeApplyAffinity(pParse, regBase, nConstraint, pIdx);
-      op = aStartOp[(start_constraints<<2) + (startEq<<1) + bRev];
-      assert( op!=0 );
-      testcase( op==OP_Rewind );
-      testcase( op==OP_Last );
-      testcase( op==OP_MoveGt );
-      testcase( op==OP_MoveGe );
-      testcase( op==OP_MoveLe );
-      testcase( op==OP_MoveLt );
-      sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase, 
-                        (char*)nConstraint, P4_INT32);
-
-      /* Load the value for the inequality constraint at the end of the
-      ** range (if any).
-      */
-      nConstraint = nEq;
-      if( pRangeEnd ){
-        sqlite3ExprCode(pParse, pRangeEnd->pExpr->pRight, regBase+nEq);
-        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
-        codeApplyAffinity(pParse, regBase, nEq+1, pIdx);
-        nConstraint++;
-      }
-
-      /* Top of the loop body */
-      pLevel->p2 = sqlite3VdbeCurrentAddr(v);
-
-      /* Check if the index cursor is past the end of the range. */
-      op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
-      testcase( op==OP_Noop );
-      testcase( op==OP_IdxGE );
-      testcase( op==OP_IdxLT );
-      sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase,
-                        (char*)nConstraint, P4_INT32);
-      sqlite3VdbeChangeP5(v, endEq!=bRev);
-
-      /* If there are inequality constraints, check that the value
-      ** of the table column that the inequality contrains is not NULL.
-      ** If it is, jump to the next iteration of the loop.
-      */
-      r1 = sqlite3GetTempReg(pParse);
-      testcase( pLevel->flags & WHERE_BTM_LIMIT );
-      testcase( pLevel->flags & WHERE_TOP_LIMIT );
-      if( pLevel->flags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT) ){
-        sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
-        sqlite3VdbeAddOp2(v, OP_IsNull, r1, cont);
-      }
+  sqlite3ResetInternalSchema(db, 0);
 
-      /* Seek the table cursor, if required */
-      if( !omitTable ){
-        sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, r1);
-        sqlite3VdbeAddOp3(v, OP_MoveGe, iCur, 0, r1);  /* Deferred seek */
-      }
-      sqlite3ReleaseTempReg(pParse, r1);
+  /* If a transaction is open, the ResetInternalSchema() call above
+  ** will not have called the xDisconnect() method on any virtual
+  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
+  ** call will do so. We need to do this before the check for active
+  ** SQL statements below, as the v-table implementation may be storing
+  ** some prepared statements internally.
+  */
+  sqlite3VtabRollback(db);
 
-      /* Record the instruction used to terminate the loop. Disable 
-      ** WHERE clause terms made redundant by the index range scan.
-      */
-      pLevel->op = bRev ? OP_Prev : OP_Next;
-      pLevel->p1 = iIdxCur;
-      disableTerm(pLevel, pRangeStart);
-      disableTerm(pLevel, pRangeEnd);
-    }else{
-      /* Case 4:  There is no usable index.  We must do a complete
-      **          scan of the entire table.
-      */
-      assert( omitTable==0 );
-      assert( bRev==0 );
-      pLevel->op = OP_Next;
-      pLevel->p1 = iCur;
-      pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, OP_Rewind, iCur, brk);
-    }
-    notReady &= ~getMask(&maskSet, iCur);
+  /* If there are any outstanding VMs, return SQLITE_BUSY. */
+  if( db->pVdbe ){
+    sqlite3Error(db, SQLITE_BUSY, 
+        "unable to close due to unfinalised statements");
+    sqlite3_mutex_leave(db->mutex);
+    return SQLITE_BUSY;
+  }
+  assert( sqlite3SafetyCheckSickOrOk(db) );
 
-    /* Insert code to test every subexpression that can be completely
-    ** computed using the current set of tables.
-    */
-    for(pTerm=wc.a, j=wc.nTerm; j>0; j--, pTerm++){
-      Expr *pE;
-      testcase( pTerm->flags & TERM_VIRTUAL );
-      testcase( pTerm->flags & TERM_CODED );
-      if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
-      if( (pTerm->prereqAll & notReady)!=0 ) continue;
-      pE = pTerm->pExpr;
-      assert( pE!=0 );
-      if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
-        continue;
-      }
-      sqlite3ExprIfFalse(pParse, pE, cont, SQLITE_JUMPIFNULL);
-      pTerm->flags |= TERM_CODED;
+  for(j=0; j<db->nDb; j++){
+    Btree *pBt = db->aDb[j].pBt;
+    if( pBt && sqlite3BtreeIsInBackup(pBt) ){
+      sqlite3Error(db, SQLITE_BUSY, 
+          "unable to close due to unfinished backup operation");
+      sqlite3_mutex_leave(db->mutex);
+      return SQLITE_BUSY;
     }
+  }
 
-    /* For a LEFT OUTER JOIN, generate code that will record the fact that
-    ** at least one row of the right table has matched the left table.  
-    */
-    if( pLevel->iLeftJoin ){
-      pLevel->top = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, pLevel->iLeftJoin);
-      VdbeComment((v, "record LEFT JOIN hit"));
-      sqlite3ExprClearColumnCache(pParse, pLevel->iTabCur);
-      sqlite3ExprClearColumnCache(pParse, pLevel->iIdxCur);
-      for(pTerm=wc.a, j=0; j<wc.nTerm; j++, pTerm++){
-        testcase( pTerm->flags & TERM_VIRTUAL );
-        testcase( pTerm->flags & TERM_CODED );
-        if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
-        if( (pTerm->prereqAll & notReady)!=0 ) continue;
-        assert( pTerm->pExpr );
-        sqlite3ExprIfFalse(pParse, pTerm->pExpr, cont, SQLITE_JUMPIFNULL);
-        pTerm->flags |= TERM_CODED;
+  /* Free any outstanding Savepoint structures. */
+  sqlite3CloseSavepoints(db);
+
+  for(j=0; j<db->nDb; j++){
+    struct Db *pDb = &db->aDb[j];
+    if( pDb->pBt ){
+      sqlite3BtreeClose(pDb->pBt);
+      pDb->pBt = 0;
+      if( j!=1 ){
+        pDb->pSchema = 0;
       }
     }
   }
+  sqlite3ResetInternalSchema(db, 0);
 
-#ifdef SQLITE_TEST  /* For testing and debugging use only */
-  /* Record in the query plan information about the current table
-  ** and the index used to access it (if any).  If the table itself
-  ** is not used, its name is just '{}'.  If no index is used
-  ** the index is listed as "{}".  If the primary key is used the
-  ** index name is '*'.
+  /* Tell the code in notify.c that the connection no longer holds any
+  ** locks and does not require any further unlock-notify callbacks.
   */
-  for(i=0; i<pTabList->nSrc; i++){
-    char *z;
-    int n;
-    pLevel = &pWInfo->a[i];
-    pTabItem = &pTabList->a[pLevel->iFrom];
-    z = pTabItem->zAlias;
-    if( z==0 ) z = pTabItem->pTab->zName;
-    n = strlen(z);
-    if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){
-      if( pLevel->flags & WHERE_IDX_ONLY ){
-        memcpy(&sqlite3_query_plan[nQPlan], "{}", 2);
-        nQPlan += 2;
-      }else{
-        memcpy(&sqlite3_query_plan[nQPlan], z, n);
-        nQPlan += n;
+  sqlite3ConnectionClosed(db);
+
+  assert( db->nDb<=2 );
+  assert( db->aDb==db->aDbStatic );
+  for(j=0; j<ArraySize(db->aFunc.a); j++){
+    FuncDef *pNext, *pHash, *p;
+    for(p=db->aFunc.a[j]; p; p=pHash){
+      pHash = p->pHash;
+      while( p ){
+        pNext = p->pNext;
+        sqlite3DbFree(db, p);
+        p = pNext;
       }
-      sqlite3_query_plan[nQPlan++] = ' ';
     }
-    testcase( pLevel->flags & WHERE_ROWID_EQ );
-    testcase( pLevel->flags & WHERE_ROWID_RANGE );
-    if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
-      memcpy(&sqlite3_query_plan[nQPlan], "* ", 2);
-      nQPlan += 2;
-    }else if( pLevel->pIdx==0 ){
-      memcpy(&sqlite3_query_plan[nQPlan], "{} ", 3);
-      nQPlan += 3;
-    }else{
-      n = strlen(pLevel->pIdx->zName);
-      if( n+nQPlan < sizeof(sqlite3_query_plan)-2 ){
-        memcpy(&sqlite3_query_plan[nQPlan], pLevel->pIdx->zName, n);
-        nQPlan += n;
-        sqlite3_query_plan[nQPlan++] = ' ';
+  }
+  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
+    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
+    /* Invoke any destructors registered for collation sequence user data. */
+    for(j=0; j<3; j++){
+      if( pColl[j].xDel ){
+        pColl[j].xDel(pColl[j].pUser);
       }
     }
+    sqlite3DbFree(db, pColl);
   }
-  while( nQPlan>0 && sqlite3_query_plan[nQPlan-1]==' ' ){
-    sqlite3_query_plan[--nQPlan] = 0;
+  sqlite3HashClear(&db->aCollSeq);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
+    Module *pMod = (Module *)sqliteHashData(i);
+    if( pMod->xDestroy ){
+      pMod->xDestroy(pMod->pAux);
+    }
+    sqlite3DbFree(db, pMod);
   }
-  sqlite3_query_plan[nQPlan] = 0;
-  nQPlan = 0;
-#endif /* SQLITE_TEST // Testing and debugging use only */
+  sqlite3HashClear(&db->aModule);
+#endif
 
-  /* Record the continuation address in the WhereInfo structure.  Then
-  ** clean up and return.
-  */
-  pWInfo->iContinue = cont;
-  whereClauseClear(&wc);
-  return pWInfo;
+  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
+  if( db->pErr ){
+    sqlite3ValueFree(db->pErr);
+  }
+  sqlite3CloseExtensions(db);
 
-  /* Jump here if malloc fails */
-whereBeginNoMem:
-  whereClauseClear(&wc);
-  whereInfoFree(pWInfo);
-  return 0;
+  db->magic = SQLITE_MAGIC_ERROR;
+
+  /* The temp-database schema is allocated differently from the other schema
+  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
+  ** So it needs to be freed here. Todo: Why not roll the temp schema into
+  ** the same sqliteMalloc() as the one that allocates the database 
+  ** structure?
+  */
+  sqlite3DbFree(db, db->aDb[1].pSchema);
+  sqlite3_mutex_leave(db->mutex);
+  db->magic = SQLITE_MAGIC_CLOSED;
+  sqlite3_mutex_free(db->mutex);
+  assert( db->lookaside.nOut==0 );  /* Fails on a lookaside memory leak */
+  if( db->lookaside.bMalloced ){
+    sqlite3_free(db->lookaside.pStart);
+  }
+  sqlite3_free(db);
+  return SQLITE_OK;
 }
 
 /*
-** Generate the end of the WHERE loop.  See comments on 
-** sqlite3WhereBegin() for additional information.
+** Rollback all database files.
 */
-SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
-  Vdbe *v = pWInfo->pParse->pVdbe;
+SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db){
   int i;
-  WhereLevel *pLevel;
-  SrcList *pTabList = pWInfo->pTabList;
-
-  /* Generate loop termination code.
-  */
-  sqlite3ExprClearColumnCache(pWInfo->pParse, -1);
-  for(i=pTabList->nSrc-1; i>=0; i--){
-    pLevel = &pWInfo->a[i];
-    sqlite3VdbeResolveLabel(v, pLevel->cont);
-    if( pLevel->op!=OP_Noop ){
-      sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2);
-    }
-    if( pLevel->nIn ){
-      struct InLoop *pIn;
-      int j;
-      sqlite3VdbeResolveLabel(v, pLevel->nxt);
-      for(j=pLevel->nIn, pIn=&pLevel->aInLoop[j-1]; j>0; j--, pIn--){
-        sqlite3VdbeJumpHere(v, pIn->topAddr+1);
-        sqlite3VdbeAddOp2(v, OP_Next, pIn->iCur, pIn->topAddr);
-        sqlite3VdbeJumpHere(v, pIn->topAddr-1);
-      }
-      sqlite3_free(pLevel->aInLoop);
-    }
-    sqlite3VdbeResolveLabel(v, pLevel->brk);
-    if( pLevel->iLeftJoin ){
-      int addr;
-      addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin);
-      sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);
-      if( pLevel->iIdxCur>=0 ){
-        sqlite3VdbeAddOp1(v, OP_NullRow, pLevel->iIdxCur);
+  int inTrans = 0;
+  assert( sqlite3_mutex_held(db->mutex) );
+  sqlite3BeginBenignMalloc();
+  for(i=0; i<db->nDb; i++){
+    if( db->aDb[i].pBt ){
+      if( sqlite3BtreeIsInTrans(db->aDb[i].pBt) ){
+        inTrans = 1;
       }
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->top);
-      sqlite3VdbeJumpHere(v, addr);
+      sqlite3BtreeRollback(db->aDb[i].pBt);
+      db->aDb[i].inTrans = 0;
     }
   }
+  sqlite3VtabRollback(db);
+  sqlite3EndBenignMalloc();
 
-  /* The "break" point is here, just past the end of the outer loop.
-  ** Set it.
-  */
-  sqlite3VdbeResolveLabel(v, pWInfo->iBreak);
-
-  /* Close all of the cursors that were opened by sqlite3WhereBegin.
-  */
-  for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
-    struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
-    Table *pTab = pTabItem->pTab;
-    assert( pTab!=0 );
-    if( pTab->isEphem || pTab->pSelect ) continue;
-    if( !pWInfo->okOnePass && (pLevel->flags & WHERE_IDX_ONLY)==0 ){
-      sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
-    }
-    if( pLevel->pIdx!=0 ){
-      sqlite3VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);
-    }
+  if( db->flags&SQLITE_InternChanges ){
+    sqlite3ExpirePreparedStatements(db);
+    sqlite3ResetInternalSchema(db, 0);
+  }
 
-    /* If this scan uses an index, make code substitutions to read data
-    ** from the index in preference to the table. Sometimes, this means
-    ** the table need never be read from. This is a performance boost,
-    ** as the vdbe level waits until the table is read before actually
-    ** seeking the table cursor to the record corresponding to the current
-    ** position in the index.
-    ** 
-    ** Calls to the code generator in between sqlite3WhereBegin and
-    ** sqlite3WhereEnd will have created code that references the table
-    ** directly.  This loop scans all that code looking for opcodes
-    ** that reference the table and converts them into opcodes that
-    ** reference the index.
-    */
-    if( pLevel->pIdx ){
-      int k, j, last;
-      VdbeOp *pOp;
-      Index *pIdx = pLevel->pIdx;
-      int useIndexOnly = pLevel->flags & WHERE_IDX_ONLY;
+  /* Any deferred constraint violations have now been resolved. */
+  db->nDeferredCons = 0;
 
-      assert( pIdx!=0 );
-      pOp = sqlite3VdbeGetOp(v, pWInfo->iTop);
-      last = sqlite3VdbeCurrentAddr(v);
-      for(k=pWInfo->iTop; k<last; k++, pOp++){
-        if( pOp->p1!=pLevel->iTabCur ) continue;
-        if( pOp->opcode==OP_Column ){
-          for(j=0; j<pIdx->nColumn; j++){
-            if( pOp->p2==pIdx->aiColumn[j] ){
-              pOp->p2 = j;
-              pOp->p1 = pLevel->iIdxCur;
-              break;
-            }
-          }
-          assert(!useIndexOnly || j<pIdx->nColumn);
-        }else if( pOp->opcode==OP_Rowid ){
-          pOp->p1 = pLevel->iIdxCur;
-          pOp->opcode = OP_IdxRowid;
-        }else if( pOp->opcode==OP_NullRow && useIndexOnly ){
-          pOp->opcode = OP_Noop;
-        }
-      }
-    }
+  /* If one has been configured, invoke the rollback-hook callback */
+  if( db->xRollbackCallback && (inTrans || !db->autoCommit) ){
+    db->xRollbackCallback(db->pRollbackArg);
   }
-
-  /* Final cleanup
-  */
-  whereInfoFree(pWInfo);
-  return;
 }
 
-/************** End of where.c ***********************************************/
-/************** Begin file parse.c *******************************************/
-/* Driver template for the LEMON parser generator.
-** The author disclaims copyright to this source code.
-*/
-/* First off, code is include which follows the "include" declaration
-** in the input file. */
-
-
-/*
-** An instance of this structure holds information about the
-** LIMIT clause of a SELECT statement.
-*/
-struct LimitVal {
-  Expr *pLimit;    /* The LIMIT expression.  NULL if there is no limit */
-  Expr *pOffset;   /* The OFFSET expression.  NULL if there is none */
-};
-
-/*
-** An instance of this structure is used to store the LIKE,
-** GLOB, NOT LIKE, and NOT GLOB operators.
-*/
-struct LikeOp {
-  Token eOperator;  /* "like" or "glob" or "regexp" */
-  int not;         /* True if the NOT keyword is present */
-};
-
 /*
-** An instance of the following structure describes the event of a
-** TRIGGER.  "a" is the event type, one of TK_UPDATE, TK_INSERT,
-** TK_DELETE, or TK_INSTEAD.  If the event is of the form
-**
-**      UPDATE ON (a,b,c)
-**
-** Then the "b" IdList records the list "a,b,c".
+** Return a static string that describes the kind of error specified in the
+** argument.
 */
-struct TrigEvent { int a; IdList * b; };
+SQLITE_PRIVATE const char *sqlite3ErrStr(int rc){
+  static const char* const aMsg[] = {
+    /* SQLITE_OK          */ "not an error",
+    /* SQLITE_ERROR       */ "SQL logic error or missing database",
+    /* SQLITE_INTERNAL    */ 0,
+    /* SQLITE_PERM        */ "access permission denied",
+    /* SQLITE_ABORT       */ "callback requested query abort",
+    /* SQLITE_BUSY        */ "database is locked",
+    /* SQLITE_LOCKED      */ "database table is locked",
+    /* SQLITE_NOMEM       */ "out of memory",
+    /* SQLITE_READONLY    */ "attempt to write a readonly database",
+    /* SQLITE_INTERRUPT   */ "interrupted",
+    /* SQLITE_IOERR       */ "disk I/O error",
+    /* SQLITE_CORRUPT     */ "database disk image is malformed",
+    /* SQLITE_NOTFOUND    */ 0,
+    /* SQLITE_FULL        */ "database or disk is full",
+    /* SQLITE_CANTOPEN    */ "unable to open database file",
+    /* SQLITE_PROTOCOL    */ 0,
+    /* SQLITE_EMPTY       */ "table contains no data",
+    /* SQLITE_SCHEMA      */ "database schema has changed",
+    /* SQLITE_TOOBIG      */ "string or blob too big",
+    /* SQLITE_CONSTRAINT  */ "constraint failed",
+    /* SQLITE_MISMATCH    */ "datatype mismatch",
+    /* SQLITE_MISUSE      */ "library routine called out of sequence",
+    /* SQLITE_NOLFS       */ "large file support is disabled",
+    /* SQLITE_AUTH        */ "authorization denied",
+    /* SQLITE_FORMAT      */ "auxiliary database format error",
+    /* SQLITE_RANGE       */ "bind or column index out of range",
+    /* SQLITE_NOTADB      */ "file is encrypted or is not a database",
+  };
+  rc &= 0xff;
+  if( ALWAYS(rc>=0) && rc<(int)(sizeof(aMsg)/sizeof(aMsg[0])) && aMsg[rc]!=0 ){
+    return aMsg[rc];
+  }else{
+    return "unknown error";
+  }
+}
 
 /*
-** An instance of this structure holds the ATTACH key and the key type.
+** This routine implements a busy callback that sleeps and tries
+** again until a timeout value is reached.  The timeout value is
+** an integer number of milliseconds passed in as the first
+** argument.
 */
-struct AttachKey { int type;  Token key; };
+static int sqliteDefaultBusyCallback(
+ void *ptr,               /* Database connection */
+ int count                /* Number of times table has been busy */
+){
+#if SQLITE_OS_WIN || (defined(HAVE_USLEEP) && HAVE_USLEEP)
+  static const u8 delays[] =
+     { 1, 2, 5, 10, 15, 20, 25, 25,  25,  50,  50, 100 };
+  static const u8 totals[] =
+     { 0, 1, 3,  8, 18, 33, 53, 78, 103, 128, 178, 228 };
+# define NDELAY (sizeof(delays)/sizeof(delays[0]))
+  sqlite3 *db = (sqlite3 *)ptr;
+  int timeout = db->busyTimeout;
+  int delay, prior;
 
-/* Next is all token values, in a form suitable for use by makeheaders.
-** This section will be null unless lemon is run with the -m switch.
-*/
-/* 
-** These constants (all generated automatically by the parser generator)
-** specify the various kinds of tokens (terminals) that the parser
-** understands. 
-**
-** Each symbol here is a terminal symbol in the grammar.
-*/
-/* Make sure the INTERFACE macro is defined.
-*/
-#ifndef INTERFACE
-# define INTERFACE 1
-#endif
-/* The next thing included is series of defines which control
-** various aspects of the generated parser.
-**    YYCODETYPE         is the data type used for storing terminal
-**                       and nonterminal numbers.  "unsigned char" is
-**                       used if there are fewer than 250 terminals
-**                       and nonterminals.  "int" is used otherwise.
-**    YYNOCODE           is a number of type YYCODETYPE which corresponds
-**                       to no legal terminal or nonterminal number.  This
-**                       number is used to fill in empty slots of the hash 
-**                       table.
-**    YYFALLBACK         If defined, this indicates that one or more tokens
-**                       have fall-back values which should be used if the
-**                       original value of the token will not parse.
-**    YYACTIONTYPE       is the data type used for storing terminal
-**                       and nonterminal numbers.  "unsigned char" is
-**                       used if there are fewer than 250 rules and
-**                       states combined.  "int" is used otherwise.
-**    sqlite3ParserTOKENTYPE     is the data type used for minor tokens given 
-**                       directly to the parser from the tokenizer.
-**    YYMINORTYPE        is the data type used for all minor tokens.
-**                       This is typically a union of many types, one of
-**                       which is sqlite3ParserTOKENTYPE.  The entry in the union
-**                       for base tokens is called "yy0".
-**    YYSTACKDEPTH       is the maximum depth of the parser's stack.  If
-**                       zero the stack is dynamically sized using realloc()
-**    sqlite3ParserARG_SDECL     A static variable declaration for the %extra_argument
-**    sqlite3ParserARG_PDECL     A parameter declaration for the %extra_argument
-**    sqlite3ParserARG_STORE     Code to store %extra_argument into yypParser
-**    sqlite3ParserARG_FETCH     Code to extract %extra_argument from yypParser
-**    YYNSTATE           the combined number of states.
-**    YYNRULE            the number of rules in the grammar
-**    YYERRORSYMBOL      is the code number of the error symbol.  If not
-**                       defined, then do no error processing.
-*/
-#define YYCODETYPE unsigned char
-#define YYNOCODE 248
-#define YYACTIONTYPE unsigned short int
-#define YYWILDCARD 59
-#define sqlite3ParserTOKENTYPE Token
-typedef union {
-  sqlite3ParserTOKENTYPE yy0;
-  int yy46;
-  struct LikeOp yy72;
-  Expr* yy172;
-  ExprList* yy174;
-  Select* yy219;
-  struct LimitVal yy234;
-  TriggerStep* yy243;
-  struct TrigEvent yy370;
-  SrcList* yy373;
-  struct {int value; int mask;} yy405;
-  Token yy410;
-  IdList* yy432;
-} YYMINORTYPE;
-#ifndef YYSTACKDEPTH
-#define YYSTACKDEPTH 100
+  assert( count>=0 );
+  if( count < NDELAY ){
+    delay = delays[count];
+    prior = totals[count];
+  }else{
+    delay = delays[NDELAY-1];
+    prior = totals[NDELAY-1] + delay*(count-(NDELAY-1));
+  }
+  if( prior + delay > timeout ){
+    delay = timeout - prior;
+    if( delay<=0 ) return 0;
+  }
+  sqlite3OsSleep(db->pVfs, delay*1000);
+  return 1;
+#else
+  sqlite3 *db = (sqlite3 *)ptr;
+  int timeout = ((sqlite3 *)ptr)->busyTimeout;
+  if( (count+1)*1000 > timeout ){
+    return 0;
+  }
+  sqlite3OsSleep(db->pVfs, 1000000);
+  return 1;
 #endif
-#define sqlite3ParserARG_SDECL Parse *pParse;
-#define sqlite3ParserARG_PDECL ,Parse *pParse
-#define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
-#define sqlite3ParserARG_STORE yypParser->pParse = pParse
-#define YYNSTATE 589
-#define YYNRULE 313
-#define YYFALLBACK 1
-#define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
-#define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
-#define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)
-
-/* The yyzerominor constant is used to initialize instances of
-** YYMINORTYPE objects to zero. */
-static const YYMINORTYPE yyzerominor;
-
-/* Next are that tables used to determine what action to take based on the
-** current state and lookahead token.  These tables are used to implement
-** functions that take a state number and lookahead value and return an
-** action integer.  
-**
-** Suppose the action integer is N.  Then the action is determined as
-** follows
-**
-**   0 <= N < YYNSTATE                  Shift N.  That is, push the lookahead
-**                                      token onto the stack and goto state N.
-**
-**   YYNSTATE <= N < YYNSTATE+YYNRULE   Reduce by rule N-YYNSTATE.
-**
-**   N == YYNSTATE+YYNRULE              A syntax error has occurred.
-**
-**   N == YYNSTATE+YYNRULE+1            The parser accepts its input.
-**
-**   N == YYNSTATE+YYNRULE+2            No such action.  Denotes unused
-**                                      slots in the yy_action[] table.
-**
-** The action table is constructed as a single large table named yy_action[].
-** Given state S and lookahead X, the action is computed as
-**
-**      yy_action[ yy_shift_ofst[S] + X ]
-**
-** If the index value yy_shift_ofst[S]+X is out of range or if the value
-** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
-** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
-** and that yy_default[S] should be used instead.  
-**
-** The formula above is for computing the action when the lookahead is
-** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
-** a reduce action) then the yy_reduce_ofst[] array is used in place of
-** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
-** YY_SHIFT_USE_DFLT.
-**
-** The following are the tables generated in this section:
-**
-**  yy_action[]        A single table containing all actions.
-**  yy_lookahead[]     A table containing the lookahead for each entry in
-**                     yy_action.  Used to detect hash collisions.
-**  yy_shift_ofst[]    For each state, the offset into yy_action for
-**                     shifting terminals.
-**  yy_reduce_ofst[]   For each state, the offset into yy_action for
-**                     shifting non-terminals after a reduce.
-**  yy_default[]       Default action for each state.
-*/
-static const YYACTIONTYPE yy_action[] = {
- /*     0 */   292,  903,  124,  588,  409,  172,    2,  418,   61,   61,
- /*    10 */    61,   61,  519,   63,   63,   63,   63,   64,   64,   65,
- /*    20 */    65,   65,   66,  210,  447,  212,  425,  431,   68,   63,
- /*    30 */    63,   63,   63,   64,   64,   65,   65,   65,   66,  210,
- /*    40 */   391,  388,  396,  451,   60,   59,  297,  435,  436,  432,
- /*    50 */   432,   62,   62,   61,   61,   61,   61,  263,   63,   63,
- /*    60 */    63,   63,   64,   64,   65,   65,   65,   66,  210,  292,
- /*    70 */   493,  494,  418,  489,  208,   82,   67,  420,   69,  154,
- /*    80 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*    90 */   210,   67,  462,   69,  154,  425,  431,  574,  264,   58,
- /*   100 */    64,   64,   65,   65,   65,   66,  210,  397,  398,  422,
- /*   110 */   422,  422,  292,   60,   59,  297,  435,  436,  432,  432,
- /*   120 */    62,   62,   61,   61,   61,   61,  317,   63,   63,   63,
- /*   130 */    63,   64,   64,   65,   65,   65,   66,  210,  425,  431,
- /*   140 */    94,   65,   65,   65,   66,  210,  396,  210,  414,   34,
- /*   150 */    56,  298,  442,  443,  410,  418,   60,   59,  297,  435,
- /*   160 */   436,  432,  432,   62,   62,   61,   61,   61,   61,  208,
- /*   170 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*   180 */   210,  292,  372,  524,  295,  572,  113,  408,  522,  451,
- /*   190 */   331,  317,  407,   20,  244,  340,  519,  396,  478,  531,
- /*   200 */   505,  447,  212,  571,  570,  245,  530,  425,  431,  149,
- /*   210 */   150,  397,  398,  414,   41,  211,  151,  533,  488,  489,
- /*   220 */   418,  568,  569,  420,  292,   60,   59,  297,  435,  436,
- /*   230 */   432,  432,   62,   62,   61,   61,   61,   61,  317,   63,
- /*   240 */    63,   63,   63,   64,   64,   65,   65,   65,   66,  210,
- /*   250 */   425,  431,  447,  333,  215,  422,  422,  422,  363,  299,
- /*   260 */   414,   41,  397,  398,  366,  567,  211,  292,   60,   59,
- /*   270 */   297,  435,  436,  432,  432,   62,   62,   61,   61,   61,
- /*   280 */    61,  396,   63,   63,   63,   63,   64,   64,   65,   65,
- /*   290 */    65,   66,  210,  425,  431,  491,  300,  524,  474,   66,
- /*   300 */   210,  214,  474,  229,  411,  286,  534,   20,  449,  523,
- /*   310 */   168,   60,   59,  297,  435,  436,  432,  432,   62,   62,
- /*   320 */    61,   61,   61,   61,  474,   63,   63,   63,   63,   64,
- /*   330 */    64,   65,   65,   65,   66,  210,  209,  480,  317,   77,
- /*   340 */   292,  239,  300,   55,  484,  490,  397,  398,  181,  547,
- /*   350 */   494,  345,  348,  349,   67,  152,   69,  154,  339,  524,
- /*   360 */   414,   35,  350,  241,  221,  370,  425,  431,  579,   20,
- /*   370 */   164,  118,  243,  343,  248,  344,  176,  322,  442,  443,
- /*   380 */   414,    3,   80,  252,   60,   59,  297,  435,  436,  432,
- /*   390 */   432,   62,   62,   61,   61,   61,   61,  174,   63,   63,
- /*   400 */    63,   63,   64,   64,   65,   65,   65,   66,  210,  292,
- /*   410 */   221,  550,  236,  487,  510,  353,  317,  118,  243,  343,
- /*   420 */   248,  344,  176,  181,  317,  532,  345,  348,  349,  252,
- /*   430 */   223,  415,  155,  464,  511,  425,  431,  350,  414,   34,
- /*   440 */   465,  211,  177,  175,  160,  525,  414,   34,  338,  549,
- /*   450 */   449,  323,  168,   60,   59,  297,  435,  436,  432,  432,
- /*   460 */    62,   62,   61,   61,   61,   61,  415,   63,   63,   63,
- /*   470 */    63,   64,   64,   65,   65,   65,   66,  210,  292,  542,
- /*   480 */   335,  517,  504,  541,  456,  572,  302,   19,  331,  144,
- /*   490 */   317,  390,  317,  330,    2,  362,  457,  294,  483,  373,
- /*   500 */   269,  268,  252,  571,  425,  431,  589,  391,  388,  458,
- /*   510 */   208,  495,  414,   49,  414,   49,  303,  586,  894,  230,
- /*   520 */   894,  496,   60,   59,  297,  435,  436,  432,  432,   62,
- /*   530 */    62,   61,   61,   61,   61,  201,   63,   63,   63,   63,
- /*   540 */    64,   64,   65,   65,   65,   66,  210,  292,  317,  181,
- /*   550 */   439,  255,  345,  348,  349,  370,  153,  583,  308,  251,
- /*   560 */   309,  452,   76,  350,   78,  382,  211,  426,  427,  415,
- /*   570 */   414,   27,  319,  425,  431,  440,    1,   22,  586,  893,
- /*   580 */   396,  893,  544,  478,  320,  263,  438,  438,  429,  430,
- /*   590 */   415,   60,   59,  297,  435,  436,  432,  432,   62,   62,
- /*   600 */    61,   61,   61,   61,  237,   63,   63,   63,   63,   64,
- /*   610 */    64,   65,   65,   65,   66,  210,  292,  428,  583,  374,
- /*   620 */   224,   93,  517,    9,  159,  396,  557,  396,  456,   67,
- /*   630 */   396,   69,  154,  399,  400,  401,  320,  328,  438,  438,
- /*   640 */   457,  336,  425,  431,  361,  397,  398,  320,  433,  438,
- /*   650 */   438,  582,  291,  458,  238,  327,  318,  222,  546,  292,
- /*   660 */    60,   59,  297,  435,  436,  432,  432,   62,   62,   61,
- /*   670 */    61,   61,   61,  225,   63,   63,   63,   63,   64,   64,
- /*   680 */    65,   65,   65,   66,  210,  425,  431,  482,  313,  392,
- /*   690 */   397,  398,  397,  398,  207,  397,  398,  825,  273,  517,
- /*   700 */   251,  200,  292,   60,   59,  297,  435,  436,  432,  432,
- /*   710 */    62,   62,   61,   61,   61,   61,  470,   63,   63,   63,
- /*   720 */    63,   64,   64,   65,   65,   65,   66,  210,  425,  431,
- /*   730 */   171,  160,  263,  263,  304,  415,  276,  395,  274,  263,
- /*   740 */   517,  517,  263,  517,  192,  292,   60,   70,  297,  435,
- /*   750 */   436,  432,  432,   62,   62,   61,   61,   61,   61,  379,
- /*   760 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*   770 */   210,  425,  431,  384,  559,  305,  306,  251,  415,  320,
- /*   780 */   560,  438,  438,  561,  540,  360,  540,  387,  292,  196,
- /*   790 */    59,  297,  435,  436,  432,  432,   62,   62,   61,   61,
- /*   800 */    61,   61,  371,   63,   63,   63,   63,   64,   64,   65,
- /*   810 */    65,   65,   66,  210,  425,  431,  396,  275,  251,  251,
- /*   820 */   172,  250,  418,  415,  386,  367,  178,  179,  180,  469,
- /*   830 */   311,  123,  156,    5,  297,  435,  436,  432,  432,   62,
- /*   840 */    62,   61,   61,   61,   61,  317,   63,   63,   63,   63,
- /*   850 */    64,   64,   65,   65,   65,   66,  210,   72,  324,  194,
- /*   860 */     4,  317,  263,  317,  296,  263,  415,  414,   28,  317,
- /*   870 */   257,  317,  321,   72,  324,  317,    4,  119,  165,  177,
- /*   880 */   296,  397,  398,  414,   23,  414,   32,  418,  321,  326,
- /*   890 */   421,  414,   53,  414,   52,  317,  158,  414,   98,  451,
- /*   900 */   317,  263,  317,  277,  317,  326,  378,  471,  261,  317,
- /*   910 */   259,   18,  478,  445,  445,  451,  317,  414,   96,   75,
- /*   920 */    74,  469,  414,  101,  414,  102,  414,  112,   73,  315,
- /*   930 */   316,  414,  114,  420,  294,   75,   74,  481,  414,   16,
- /*   940 */   381,  317,  279,  467,   73,  315,  316,   72,  324,  420,
- /*   950 */     4,  208,  317,  183,  296,  317,  186,  128,   84,  208,
- /*   960 */     8,  341,  321,  414,   99,  422,  422,  422,  423,  424,
- /*   970 */    11,  623,  380,  307,  414,   33,  413,  414,   97,  326,
- /*   980 */   412,  422,  422,  422,  423,  424,   11,  415,  413,  451,
- /*   990 */   415,  162,  412,  317,  499,  500,  226,  227,  228,  104,
- /*  1000 */   448,  476,  317,  173,  507,  317,  509,  508,  317,   75,
- /*  1010 */    74,  329,  205,   21,  281,  414,   24,  418,   73,  315,
- /*  1020 */   316,  282,  317,  420,  414,   54,  460,  414,  115,  317,
- /*  1030 */   414,  116,  502,  203,  147,  549,  514,  468,  128,  202,
- /*  1040 */   317,  473,  204,  317,  414,  117,  317,  477,  317,  584,
- /*  1050 */   317,  414,   25,  317,  249,  422,  422,  422,  423,  424,
- /*  1060 */    11,  506,  414,   36,  512,  414,   37,  317,  414,   26,
- /*  1070 */   414,   38,  414,   39,  526,  414,   40,  317,  254,  317,
- /*  1080 */   128,  317,  418,  317,  256,  377,  278,  268,  585,  414,
- /*  1090 */    42,  293,  317,  352,  317,  128,  208,  513,  258,  414,
- /*  1100 */    43,  414,   44,  414,   29,  414,   30,  545,  260,  128,
- /*  1110 */   317,  553,  317,  173,  414,   45,  414,   46,  317,  262,
- /*  1120 */   383,  554,  317,   91,  564,  317,   91,  317,  581,  189,
- /*  1130 */   290,  357,  414,   47,  414,   48,  267,  365,  368,  369,
- /*  1140 */   414,   31,  270,  271,  414,   10,  272,  414,   50,  414,
- /*  1150 */    51,  556,  566,  280,  283,  284,  578,  146,  419,  405,
- /*  1160 */   231,  505,  444,  325,  516,  463,  163,  446,  552,  394,
- /*  1170 */   466,  563,  246,  515,  518,  520,  402,  403,  404,    7,
- /*  1180 */   314,   84,  232,  334,  347,   83,  332,   57,  170,   79,
- /*  1190 */   213,  461,  125,   85,  337,  342,  492,  502,  497,  301,
- /*  1200 */   498,  416,  105,  219,  247,  218,  503,  501,  233,  220,
- /*  1210 */   287,  234,  527,  528,  235,  529,  417,  521,  354,  288,
- /*  1220 */   184,  121,  185,  240,  535,  475,  242,  356,  187,  479,
- /*  1230 */   188,  358,  537,   88,  190,  548,  364,  193,  132,  376,
- /*  1240 */   555,  375,  133,  134,  135,  310,  562,  138,  136,  575,
- /*  1250 */   576,  577,  580,  100,  393,  406,  217,  142,  624,  625,
- /*  1260 */   103,  141,  265,  166,  167,  434,   71,  453,  441,  437,
- /*  1270 */   450,  143,  538,  157,  120,  454,  161,  472,  455,  169,
- /*  1280 */   459,   81,    6,   12,   13,   92,   95,  126,  216,  127,
- /*  1290 */   111,  485,  486,   17,   86,  346,  106,  122,  253,  107,
- /*  1300 */    87,  108,  182,  245,  355,  145,  351,  536,  129,  359,
- /*  1310 */   312,  130,  543,  173,  539,  266,  191,  109,  289,  551,
- /*  1320 */   195,   14,  131,  198,  197,  558,  137,  199,  139,  140,
- /*  1330 */    15,  565,   89,   90,  573,  110,  385,  206,  148,  389,
- /*  1340 */   285,  587,
-};
-static const YYCODETYPE yy_lookahead[] = {
- /*     0 */    16,  139,  140,  141,  168,   21,  144,   23,   69,   70,
- /*    10 */    71,   72,  176,   74,   75,   76,   77,   78,   79,   80,
- /*    20 */    81,   82,   83,   84,   78,   79,   42,   43,   73,   74,
- /*    30 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
- /*    40 */     1,    2,   23,   58,   60,   61,   62,   63,   64,   65,
- /*    50 */    66,   67,   68,   69,   70,   71,   72,  147,   74,   75,
- /*    60 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
- /*    70 */   185,  186,   88,   88,  110,   22,  217,   92,  219,  220,
- /*    80 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*    90 */    84,  217,  218,  219,  220,   42,   43,  238,  188,   46,
- /*   100 */    78,   79,   80,   81,   82,   83,   84,   88,   89,  124,
- /*   110 */   125,  126,   16,   60,   61,   62,   63,   64,   65,   66,
- /*   120 */    67,   68,   69,   70,   71,   72,  147,   74,   75,   76,
- /*   130 */    77,   78,   79,   80,   81,   82,   83,   84,   42,   43,
- /*   140 */    44,   80,   81,   82,   83,   84,   23,   84,  169,  170,
- /*   150 */    19,  164,  165,  166,   23,   23,   60,   61,   62,   63,
- /*   160 */    64,   65,   66,   67,   68,   69,   70,   71,   72,  110,
- /*   170 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*   180 */    84,   16,  123,  147,  150,  147,   21,  167,  168,   58,
- /*   190 */   211,  147,  156,  157,   92,  216,  176,   23,  147,  176,
- /*   200 */   177,   78,   79,  165,  166,  103,  183,   42,   43,   78,
- /*   210 */    79,   88,   89,  169,  170,  228,  180,  181,  169,   88,
- /*   220 */    88,   98,   99,   92,   16,   60,   61,   62,   63,   64,
- /*   230 */    65,   66,   67,   68,   69,   70,   71,   72,  147,   74,
- /*   240 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
- /*   250 */    42,   43,   78,  209,  210,  124,  125,  126,  224,  208,
- /*   260 */   169,  170,   88,   89,  230,  227,  228,   16,   60,   61,
- /*   270 */    62,   63,   64,   65,   66,   67,   68,   69,   70,   71,
- /*   280 */    72,   23,   74,   75,   76,   77,   78,   79,   80,   81,
- /*   290 */    82,   83,   84,   42,   43,  160,   16,  147,  161,   83,
- /*   300 */    84,  210,  161,  153,  169,  158,  156,  157,  161,  162,
- /*   310 */   163,   60,   61,   62,   63,   64,   65,   66,   67,   68,
- /*   320 */    69,   70,   71,   72,  161,   74,   75,   76,   77,   78,
- /*   330 */    79,   80,   81,   82,   83,   84,  192,  200,  147,  131,
- /*   340 */    16,  200,   16,  199,   20,  169,   88,   89,   90,  185,
- /*   350 */   186,   93,   94,   95,  217,   22,  219,  220,  147,  147,
- /*   360 */   169,  170,  104,  200,   84,  147,   42,   43,  156,  157,
- /*   370 */    90,   91,   92,   93,   94,   95,   96,  164,  165,  166,
- /*   380 */   169,  170,  131,  103,   60,   61,   62,   63,   64,   65,
- /*   390 */    66,   67,   68,   69,   70,   71,   72,  155,   74,   75,
- /*   400 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
- /*   410 */    84,   11,  221,   20,   30,   16,  147,   91,   92,   93,
- /*   420 */    94,   95,   96,   90,  147,  181,   93,   94,   95,  103,
- /*   430 */   212,  189,  155,   27,   50,   42,   43,  104,  169,  170,
- /*   440 */    34,  228,   43,  201,  202,  181,  169,  170,  206,   49,
- /*   450 */   161,  162,  163,   60,   61,   62,   63,   64,   65,   66,
- /*   460 */    67,   68,   69,   70,   71,   72,  189,   74,   75,   76,
- /*   470 */    77,   78,   79,   80,   81,   82,   83,   84,   16,   25,
- /*   480 */   211,  147,   20,   29,   12,  147,  102,   19,  211,   21,
- /*   490 */   147,  141,  147,  216,  144,   41,   24,   98,   20,   99,
- /*   500 */   100,  101,  103,  165,   42,   43,    0,    1,    2,   37,
- /*   510 */   110,   39,  169,  170,  169,  170,  182,   19,   20,  190,
- /*   520 */    22,   49,   60,   61,   62,   63,   64,   65,   66,   67,
- /*   530 */    68,   69,   70,   71,   72,  155,   74,   75,   76,   77,
- /*   540 */    78,   79,   80,   81,   82,   83,   84,   16,  147,   90,
- /*   550 */    20,   20,   93,   94,   95,  147,  155,   59,  215,  225,
- /*   560 */   215,   20,  130,  104,  132,  227,  228,   42,   43,  189,
- /*   570 */   169,  170,   16,   42,   43,   20,   19,   22,   19,   20,
- /*   580 */    23,   22,   18,  147,  106,  147,  108,  109,   63,   64,
- /*   590 */   189,   60,   61,   62,   63,   64,   65,   66,   67,   68,
- /*   600 */    69,   70,   71,   72,  147,   74,   75,   76,   77,   78,
- /*   610 */    79,   80,   81,   82,   83,   84,   16,   92,   59,   55,
- /*   620 */   212,   21,  147,   19,  147,   23,  188,   23,   12,  217,
- /*   630 */    23,  219,  220,    7,    8,    9,  106,  186,  108,  109,
- /*   640 */    24,  147,   42,   43,  208,   88,   89,  106,   92,  108,
- /*   650 */   109,  244,  245,   37,  147,   39,  147,  182,   94,   16,
- /*   660 */    60,   61,   62,   63,   64,   65,   66,   67,   68,   69,
- /*   670 */    70,   71,   72,  145,   74,   75,   76,   77,   78,   79,
- /*   680 */    80,   81,   82,   83,   84,   42,   43,   80,  142,  143,
- /*   690 */    88,   89,   88,   89,  148,   88,   89,  133,   14,  147,
- /*   700 */   225,  155,   16,   60,   61,   62,   63,   64,   65,   66,
- /*   710 */    67,   68,   69,   70,   71,   72,  114,   74,   75,   76,
- /*   720 */    77,   78,   79,   80,   81,   82,   83,   84,   42,   43,
- /*   730 */   201,  202,  147,  147,  182,  189,   52,  147,   54,  147,
- /*   740 */   147,  147,  147,  147,  155,   16,   60,   61,   62,   63,
- /*   750 */    64,   65,   66,   67,   68,   69,   70,   71,   72,  213,
- /*   760 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*   770 */    84,   42,   43,  188,  188,  182,  182,  225,  189,  106,
- /*   780 */   188,  108,  109,  188,   99,  100,  101,  241,   16,  155,
- /*   790 */    61,   62,   63,   64,   65,   66,   67,   68,   69,   70,
- /*   800 */    71,   72,  213,   74,   75,   76,   77,   78,   79,   80,
- /*   810 */    81,   82,   83,   84,   42,   43,   23,  133,  225,  225,
- /*   820 */    21,  225,   23,  189,  239,  236,   99,  100,  101,   22,
- /*   830 */   242,  243,  155,  191,   62,   63,   64,   65,   66,   67,
- /*   840 */    68,   69,   70,   71,   72,  147,   74,   75,   76,   77,
- /*   850 */    78,   79,   80,   81,   82,   83,   84,   16,   17,   22,
- /*   860 */    19,  147,  147,  147,   23,  147,  189,  169,  170,  147,
- /*   870 */    14,  147,   31,   16,   17,  147,   19,  147,   19,   43,
- /*   880 */    23,   88,   89,  169,  170,  169,  170,   88,   31,   48,
- /*   890 */   147,  169,  170,  169,  170,  147,   89,  169,  170,   58,
- /*   900 */   147,  147,  147,  188,  147,   48,  188,  114,   52,  147,
- /*   910 */    54,   19,  147,  124,  125,   58,  147,  169,  170,   78,
- /*   920 */    79,  114,  169,  170,  169,  170,  169,  170,   87,   88,
- /*   930 */    89,  169,  170,   92,   98,   78,   79,   80,  169,  170,
- /*   940 */    91,  147,  188,   22,   87,   88,   89,   16,   17,   92,
- /*   950 */    19,  110,  147,  155,   23,  147,  155,   22,  121,  110,
- /*   960 */    68,   80,   31,  169,  170,  124,  125,  126,  127,  128,
- /*   970 */   129,  112,  123,  208,  169,  170,  107,  169,  170,   48,
- /*   980 */   111,  124,  125,  126,  127,  128,  129,  189,  107,   58,
- /*   990 */   189,    5,  111,  147,    7,    8,   10,   11,   12,   13,
- /*  1000 */   161,   20,  147,   22,  178,  147,   91,   92,  147,   78,
- /*  1010 */    79,  147,   26,   19,   28,  169,  170,   23,   87,   88,
- /*  1020 */    89,   35,  147,   92,  169,  170,  147,  169,  170,  147,
- /*  1030 */   169,  170,   97,   47,  113,   49,   20,  203,   22,   53,
- /*  1040 */   147,  147,   56,  147,  169,  170,  147,  147,  147,   20,
- /*  1050 */   147,  169,  170,  147,  147,  124,  125,  126,  127,  128,
- /*  1060 */   129,  147,  169,  170,  178,  169,  170,  147,  169,  170,
- /*  1070 */   169,  170,  169,  170,  147,  169,  170,  147,   20,  147,
- /*  1080 */    22,  147,   88,  147,  147,   99,  100,  101,   59,  169,
- /*  1090 */   170,  105,  147,   20,  147,   22,  110,  178,  147,  169,
- /*  1100 */   170,  169,  170,  169,  170,  169,  170,   20,  147,   22,
- /*  1110 */   147,   20,  147,   22,  169,  170,  169,  170,  147,  147,
- /*  1120 */   134,   20,  147,   22,   20,  147,   22,  147,   20,  232,
- /*  1130 */    22,  233,  169,  170,  169,  170,  147,  147,  147,  147,
- /*  1140 */   169,  170,  147,  147,  169,  170,  147,  169,  170,  169,
- /*  1150 */   170,  147,  147,  147,  147,  147,  147,  191,  161,  149,
- /*  1160 */   193,  177,  229,  223,  161,  172,    6,  229,  194,  146,
- /*  1170 */   172,  194,  172,  172,  172,  161,  146,  146,  146,   22,
- /*  1180 */   154,  121,  194,  118,  173,  119,  116,  120,  112,  130,
- /*  1190 */   222,  152,  152,   98,  115,   98,  171,   97,  171,   40,
- /*  1200 */   179,  189,   19,   84,  171,  226,  171,  173,  195,  226,
- /*  1210 */   174,  196,  171,  171,  197,  171,  198,  179,   15,  174,
- /*  1220 */   151,   60,  151,  204,  152,  205,  204,  152,  151,  205,
- /*  1230 */   152,   38,  152,  130,  151,  184,  152,  184,   19,   15,
- /*  1240 */   194,  152,  187,  187,  187,  152,  194,  184,  187,   33,
- /*  1250 */   152,  152,  137,  159,    1,   20,  175,  214,  112,  112,
- /*  1260 */   175,  214,  234,  112,  112,   92,   19,   11,   20,  107,
- /*  1270 */    20,   19,  235,   19,   32,   20,  112,  114,   20,   22,
- /*  1280 */    20,   22,  117,   22,  117,  237,  237,   19,   44,   20,
- /*  1290 */   240,   20,   20,  231,   19,   44,   19,  243,   20,   19,
- /*  1300 */    19,   19,   96,  103,   16,   21,   44,   17,   98,   36,
- /*  1310 */   246,   45,   45,   22,   51,  133,   98,   19,    5,    1,
- /*  1320 */   122,   19,  102,   14,  113,   17,  113,  115,  102,  122,
- /*  1330 */    19,  123,   68,   68,   20,   14,   57,  135,   19,    3,
- /*  1340 */   136,    4,
-};
-#define YY_SHIFT_USE_DFLT (-62)
-#define YY_SHIFT_MAX 389
-static const short yy_shift_ofst[] = {
- /*     0 */    39,  841,  986,  -16,  841,  931,  931,  258,  123,  -36,
- /*    10 */    96,  931,  931,  931,  931,  931,  -45,  400,  174,   19,
- /*    20 */   132,  -54,  -54,   53,  165,  208,  251,  324,  393,  462,
- /*    30 */   531,  600,  643,  686,  643,  643,  643,  643,  643,  643,
- /*    40 */   643,  643,  643,  643,  643,  643,  643,  643,  643,  643,
- /*    50 */   643,  643,  729,  772,  772,  857,  931,  931,  931,  931,
- /*    60 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    70 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    80 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    90 */   931,  931,  931,  931,  931,  931,  -61,  -61,    6,    6,
- /*   100 */   280,   22,   61,  399,  564,   19,   19,   19,   19,   19,
- /*   110 */    19,   19,  216,  132,   63,  -62,  -62,  -62,  131,  326,
- /*   120 */   472,  472,  498,  559,  506,  799,   19,  799,   19,   19,
- /*   130 */    19,   19,   19,   19,   19,   19,   19,   19,   19,   19,
- /*   140 */    19,  849,   59,  -36,  -36,  -36,  -62,  -62,  -62,  -15,
- /*   150 */   -15,  333,  459,  478,  557,  530,  541,  616,  602,  793,
- /*   160 */   604,  607,  626,   19,   19,  881,   19,   19,  994,   19,
- /*   170 */    19,  807,   19,   19,  673,  807,   19,   19,  384,  384,
- /*   180 */   384,   19,   19,  673,   19,   19,  673,   19,  454,  685,
- /*   190 */    19,   19,  673,   19,   19,   19,  673,   19,   19,   19,
- /*   200 */   673,  673,   19,   19,   19,   19,   19,  468,  869,  921,
- /*   210 */   132,  789,  789,  432,  406,  406,  406,  836,  406,  132,
- /*   220 */   406,  132,  935,  837,  837, 1160, 1160, 1160, 1160, 1157,
- /*   230 */   -36, 1060, 1065, 1066, 1070, 1067, 1059, 1076, 1076, 1095,
- /*   240 */  1079, 1095, 1079, 1097, 1097, 1159, 1097, 1100, 1097, 1183,
- /*   250 */  1119, 1119, 1159, 1097, 1097, 1097, 1183, 1203, 1076, 1203,
- /*   260 */  1076, 1203, 1076, 1076, 1193, 1103, 1203, 1076, 1161, 1161,
- /*   270 */  1219, 1060, 1076, 1224, 1224, 1224, 1224, 1060, 1161, 1219,
- /*   280 */  1076, 1216, 1216, 1076, 1076, 1115,  -62,  -62,  -62,  -62,
- /*   290 */   -62,  -62,  525,  684,  727,  856,  859,  556,  555,  981,
- /*   300 */   102,  987,  915, 1016, 1058, 1073, 1087, 1091, 1101, 1104,
- /*   310 */   892, 1108, 1029, 1253, 1235, 1146, 1147, 1151, 1152, 1173,
- /*   320 */  1162, 1247, 1248, 1250, 1252, 1256, 1254, 1255, 1257, 1258,
- /*   330 */  1260, 1259, 1165, 1261, 1167, 1259, 1163, 1268, 1269, 1164,
- /*   340 */  1271, 1272, 1242, 1244, 1275, 1251, 1277, 1278, 1280, 1281,
- /*   350 */  1262, 1282, 1206, 1200, 1288, 1290, 1284, 1210, 1273, 1263,
- /*   360 */  1266, 1291, 1267, 1182, 1218, 1298, 1313, 1318, 1220, 1264,
- /*   370 */  1265, 1198, 1302, 1211, 1309, 1212, 1308, 1213, 1226, 1207,
- /*   380 */  1311, 1208, 1314, 1321, 1279, 1202, 1204, 1319, 1336, 1337,
-};
-#define YY_REDUCE_USE_DFLT (-165)
-#define YY_REDUCE_MAX 291
-static const short yy_reduce_ofst[] = {
- /*     0 */  -138,  277,  546,  137,  401,  -21,   44,   36,   38,  242,
- /*    10 */  -141,  191,   91,  269,  343,  345, -126,  589,  338,  150,
- /*    20 */   147,  -13,  213,  412,  412,  412,  412,  412,  412,  412,
- /*    30 */   412,  412,  412,  412,  412,  412,  412,  412,  412,  412,
- /*    40 */   412,  412,  412,  412,  412,  412,  412,  412,  412,  412,
- /*    50 */   412,  412,  412,  412,  412,  211,  698,  714,  716,  722,
- /*    60 */   724,  728,  748,  753,  755,  757,  762,  769,  794,  805,
- /*    70 */   808,  846,  855,  858,  861,  875,  882,  893,  896,  899,
- /*    80 */   901,  903,  906,  920,  930,  932,  934,  936,  945,  947,
- /*    90 */   963,  965,  971,  975,  978,  980,  412,  412,  412,  412,
- /*   100 */    20,  412,  412,   23,   34,  334,  475,  552,  593,  594,
- /*   110 */   585,  212,  412,  289,  412,  412,  412,  412,  135, -164,
- /*   120 */  -115,  164,  407,  407,  350,  141,   51,  163,  596,  -90,
- /*   130 */   436,  218,  765,  438,  586,  592,  595,  715,  718,  408,
- /*   140 */   754,  380,  634,  677,  798,  801,  144,  529,  588,   49,
- /*   150 */   176,  244,  264,  329,  457,  329,  329,  451,  477,  494,
- /*   160 */   507,  509,  528,  590,  730,  642,  509,  743,  839,  864,
- /*   170 */   879,  834,  894,  900,  329,  834,  907,  914,  826,  886,
- /*   180 */   919,  927,  937,  329,  951,  961,  329,  972,  897,  898,
- /*   190 */   989,  990,  329,  991,  992,  995,  329,  996,  999, 1004,
- /*   200 */   329,  329, 1005, 1006, 1007, 1008, 1009, 1010,  966,  967,
- /*   210 */   997,  933,  938,  940,  993,  998, 1000,  984, 1001, 1003,
- /*   220 */  1002, 1014, 1011,  974,  977, 1023, 1030, 1031, 1032, 1026,
- /*   230 */  1012,  988, 1013, 1015, 1017, 1018,  968, 1039, 1040, 1019,
- /*   240 */  1020, 1022, 1024, 1025, 1027, 1021, 1033, 1034, 1035, 1036,
- /*   250 */   979,  983, 1038, 1041, 1042, 1044, 1045, 1069, 1072, 1071,
- /*   260 */  1075, 1077, 1078, 1080, 1028, 1037, 1083, 1084, 1051, 1053,
- /*   270 */  1043, 1046, 1089, 1055, 1056, 1057, 1061, 1052, 1063, 1047,
- /*   280 */  1093, 1048, 1049, 1098, 1099, 1050, 1094, 1081, 1085, 1062,
- /*   290 */  1054, 1064,
-};
-static const YYACTIONTYPE yy_default[] = {
- /*     0 */   595,  820,  902,  710,  902,  820,  902,  902,  848,  714,
- /*    10 */   877,  818,  902,  902,  902,  902,  792,  902,  848,  902,
- /*    20 */   626,  848,  848,  743,  902,  902,  902,  902,  902,  902,
- /*    30 */   902,  902,  744,  902,  822,  817,  813,  815,  814,  821,
- /*    40 */   745,  734,  741,  748,  726,  861,  750,  751,  757,  758,
- /*    50 */   878,  876,  780,  779,  798,  902,  902,  902,  902,  902,
- /*    60 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*    70 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*    80 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*    90 */   902,  902,  902,  902,  902,  902,  782,  804,  781,  791,
- /*   100 */   619,  783,  784,  679,  614,  902,  902,  902,  902,  902,
- /*   110 */   902,  902,  785,  902,  786,  799,  800,  801,  902,  902,
- /*   120 */   902,  902,  902,  902,  595,  710,  902,  710,  902,  902,
- /*   130 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   140 */   902,  902,  902,  902,  902,  902,  704,  714,  895,  902,
- /*   150 */   902,  670,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   160 */   902,  902,  602,  600,  902,  702,  902,  902,  628,  902,
- /*   170 */   902,  712,  902,  902,  717,  718,  902,  902,  902,  902,
- /*   180 */   902,  902,  902,  616,  902,  902,  691,  902,  854,  902,
- /*   190 */   902,  902,  868,  902,  902,  902,  866,  902,  902,  902,
- /*   200 */   693,  753,  834,  902,  881,  883,  902,  902,  702,  711,
- /*   210 */   902,  902,  902,  816,  737,  737,  737,  649,  737,  902,
- /*   220 */   737,  902,  652,  747,  747,  599,  599,  599,  599,  669,
- /*   230 */   902,  747,  738,  740,  730,  742,  902,  719,  719,  727,
- /*   240 */   729,  727,  729,  681,  681,  666,  681,  652,  681,  826,
- /*   250 */   831,  831,  666,  681,  681,  681,  826,  611,  719,  611,
- /*   260 */   719,  611,  719,  719,  858,  860,  611,  719,  683,  683,
- /*   270 */   759,  747,  719,  690,  690,  690,  690,  747,  683,  759,
- /*   280 */   719,  880,  880,  719,  719,  888,  636,  654,  654,  863,
- /*   290 */   895,  900,  902,  902,  902,  902,  766,  902,  902,  902,
- /*   300 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   310 */   841,  902,  902,  902,  902,  771,  767,  902,  768,  902,
- /*   320 */   696,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   330 */   902,  819,  902,  731,  902,  739,  902,  902,  902,  902,
- /*   340 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   350 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   360 */   856,  857,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   370 */   902,  902,  902,  902,  902,  902,  902,  902,  902,  902,
- /*   380 */   902,  902,  902,  902,  887,  902,  902,  890,  596,  902,
- /*   390 */   590,  593,  592,  594,  598,  601,  623,  624,  625,  603,
- /*   400 */   604,  605,  606,  607,  608,  609,  615,  617,  635,  637,
- /*   410 */   621,  639,  700,  701,  763,  694,  695,  699,  622,  774,
- /*   420 */   765,  769,  770,  772,  773,  787,  788,  790,  796,  803,
- /*   430 */   806,  789,  794,  795,  797,  802,  805,  697,  698,  809,
- /*   440 */   629,  630,  633,  634,  844,  846,  845,  847,  632,  631,
- /*   450 */   775,  778,  811,  812,  869,  870,  871,  872,  873,  807,
- /*   460 */   720,  810,  793,  732,  735,  736,  733,  703,  713,  722,
- /*   470 */   723,  724,  725,  708,  709,  715,  728,  761,  762,  716,
- /*   480 */   705,  706,  707,  808,  764,  776,  777,  640,  641,  771,
- /*   490 */   642,  643,  644,  682,  685,  686,  687,  645,  664,  667,
- /*   500 */   668,  646,  653,  647,  648,  655,  656,  657,  660,  661,
- /*   510 */   662,  663,  658,  659,  827,  828,  832,  830,  829,  650,
- /*   520 */   651,  665,  638,  627,  620,  671,  674,  675,  676,  677,
- /*   530 */   678,  680,  672,  673,  618,  610,  612,  721,  850,  859,
- /*   540 */   855,  851,  852,  853,  613,  823,  824,  684,  755,  756,
- /*   550 */   849,  862,  864,  760,  865,  867,  892,  688,  689,  692,
- /*   560 */   833,  874,  746,  749,  752,  754,  835,  836,  837,  838,
- /*   570 */   839,  842,  843,  840,  875,  879,  882,  884,  885,  886,
- /*   580 */   889,  891,  896,  897,  898,  901,  899,  597,  591,
-};
-#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
+}
 
-/* The next table maps tokens into fallback tokens.  If a construct
-** like the following:
-** 
-**      %fallback ID X Y Z.
+/*
+** Invoke the given busy handler.
 **
-** appears in the grammer, then ID becomes a fallback token for X, Y,
-** and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
-** but it does not parse, the type of the token is changed to ID and
-** the parse is retried before an error is thrown.
+** This routine is called when an operation failed with a lock.
+** If this routine returns non-zero, the lock is retried.  If it
+** returns 0, the operation aborts with an SQLITE_BUSY error.
 */
-#ifdef YYFALLBACK
-static const YYCODETYPE yyFallback[] = {
-    0,  /*          $ => nothing */
-    0,  /*       SEMI => nothing */
-   23,  /*    EXPLAIN => ID */
-   23,  /*      QUERY => ID */
-   23,  /*       PLAN => ID */
-   23,  /*      BEGIN => ID */
-    0,  /* TRANSACTION => nothing */
-   23,  /*   DEFERRED => ID */
-   23,  /*  IMMEDIATE => ID */
-   23,  /*  EXCLUSIVE => ID */
-    0,  /*     COMMIT => nothing */
-   23,  /*        END => ID */
-    0,  /*   ROLLBACK => nothing */
-    0,  /*     CREATE => nothing */
-    0,  /*      TABLE => nothing */
-   23,  /*         IF => ID */
-    0,  /*        NOT => nothing */
-    0,  /*     EXISTS => nothing */
-   23,  /*       TEMP => ID */
-    0,  /*         LP => nothing */
-    0,  /*         RP => nothing */
-    0,  /*         AS => nothing */
-    0,  /*      COMMA => nothing */
-    0,  /*         ID => nothing */
-   23,  /*      ABORT => ID */
-   23,  /*      AFTER => ID */
-   23,  /*    ANALYZE => ID */
-   23,  /*        ASC => ID */
-   23,  /*     ATTACH => ID */
-   23,  /*     BEFORE => ID */
-   23,  /*    CASCADE => ID */
-   23,  /*       CAST => ID */
-   23,  /*   CONFLICT => ID */
-   23,  /*   DATABASE => ID */
-   23,  /*       DESC => ID */
-   23,  /*     DETACH => ID */
-   23,  /*       EACH => ID */
-   23,  /*       FAIL => ID */
-   23,  /*        FOR => ID */
-   23,  /*     IGNORE => ID */
-   23,  /*  INITIALLY => ID */
-   23,  /*    INSTEAD => ID */
-   23,  /*    LIKE_KW => ID */
-   23,  /*      MATCH => ID */
-   23,  /*        KEY => ID */
-   23,  /*         OF => ID */
-   23,  /*     OFFSET => ID */
-   23,  /*     PRAGMA => ID */
-   23,  /*      RAISE => ID */
-   23,  /*    REPLACE => ID */
-   23,  /*   RESTRICT => ID */
-   23,  /*        ROW => ID */
-   23,  /*    TRIGGER => ID */
-   23,  /*     VACUUM => ID */
-   23,  /*       VIEW => ID */
-   23,  /*    VIRTUAL => ID */
-   23,  /*    REINDEX => ID */
-   23,  /*     RENAME => ID */
-   23,  /*   CTIME_KW => ID */
-    0,  /*        ANY => nothing */
-    0,  /*         OR => nothing */
-    0,  /*        AND => nothing */
-    0,  /*         IS => nothing */
-    0,  /*    BETWEEN => nothing */
-    0,  /*         IN => nothing */
-    0,  /*     ISNULL => nothing */
-    0,  /*    NOTNULL => nothing */
-    0,  /*         NE => nothing */
-    0,  /*         EQ => nothing */
-    0,  /*         GT => nothing */
-    0,  /*         LE => nothing */
-    0,  /*         LT => nothing */
-    0,  /*         GE => nothing */
-    0,  /*     ESCAPE => nothing */
-    0,  /*     BITAND => nothing */
-    0,  /*      BITOR => nothing */
-    0,  /*     LSHIFT => nothing */
-    0,  /*     RSHIFT => nothing */
-    0,  /*       PLUS => nothing */
-    0,  /*      MINUS => nothing */
-    0,  /*       STAR => nothing */
-    0,  /*      SLASH => nothing */
-    0,  /*        REM => nothing */
-    0,  /*     CONCAT => nothing */
-    0,  /*    COLLATE => nothing */
-    0,  /*     UMINUS => nothing */
-    0,  /*      UPLUS => nothing */
-    0,  /*     BITNOT => nothing */
-    0,  /*     STRING => nothing */
-    0,  /*    JOIN_KW => nothing */
-    0,  /* CONSTRAINT => nothing */
-    0,  /*    DEFAULT => nothing */
-    0,  /*       NULL => nothing */
-    0,  /*    PRIMARY => nothing */
-    0,  /*     UNIQUE => nothing */
-    0,  /*      CHECK => nothing */
-    0,  /* REFERENCES => nothing */
-    0,  /*   AUTOINCR => nothing */
-    0,  /*         ON => nothing */
-    0,  /*     DELETE => nothing */
-    0,  /*     UPDATE => nothing */
-    0,  /*     INSERT => nothing */
-    0,  /*        SET => nothing */
-    0,  /* DEFERRABLE => nothing */
-    0,  /*    FOREIGN => nothing */
-    0,  /*       DROP => nothing */
-    0,  /*      UNION => nothing */
-    0,  /*        ALL => nothing */
-    0,  /*     EXCEPT => nothing */
-    0,  /*  INTERSECT => nothing */
-    0,  /*     SELECT => nothing */
-    0,  /*   DISTINCT => nothing */
-    0,  /*        DOT => nothing */
-    0,  /*       FROM => nothing */
-    0,  /*       JOIN => nothing */
-    0,  /*      USING => nothing */
-    0,  /*      ORDER => nothing */
-    0,  /*         BY => nothing */
-    0,  /*      GROUP => nothing */
-    0,  /*     HAVING => nothing */
-    0,  /*      LIMIT => nothing */
-    0,  /*      WHERE => nothing */
-    0,  /*       INTO => nothing */
-    0,  /*     VALUES => nothing */
-    0,  /*    INTEGER => nothing */
-    0,  /*      FLOAT => nothing */
-    0,  /*       BLOB => nothing */
-    0,  /*   REGISTER => nothing */
-    0,  /*   VARIABLE => nothing */
-    0,  /*       CASE => nothing */
-    0,  /*       WHEN => nothing */
-    0,  /*       THEN => nothing */
-    0,  /*       ELSE => nothing */
-    0,  /*      INDEX => nothing */
-    0,  /*      ALTER => nothing */
-    0,  /*         TO => nothing */
-    0,  /*        ADD => nothing */
-    0,  /*   COLUMNKW => nothing */
-};
-#endif /* YYFALLBACK */
+SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler *p){
+  int rc;
+  if( NEVER(p==0) || p->xFunc==0 || p->nBusy<0 ) return 0;
+  rc = p->xFunc(p->pArg, p->nBusy);
+  if( rc==0 ){
+    p->nBusy = -1;
+  }else{
+    p->nBusy++;
+  }
+  return rc; 
+}
 
-/* The following structure represents a single element of the
-** parser's stack.  Information stored includes:
-**
-**   +  The state number for the parser at this level of the stack.
-**
-**   +  The value of the token stored at this level of the stack.
-**      (In other words, the "major" token.)
-**
-**   +  The semantic value stored at this level of the stack.  This is
-**      the information used by the action routines in the grammar.
-**      It is sometimes called the "minor" token.
+/*
+** This routine sets the busy callback for an Sqlite database to the
+** given callback function with the given argument.
 */
-struct yyStackEntry {
-  int stateno;       /* The state-number */
-  int major;         /* The major token value.  This is the code
-                     ** number for the token at this stack level */
-  YYMINORTYPE minor; /* The user-supplied minor token value.  This
-                     ** is the value of the token  */
-};
-typedef struct yyStackEntry yyStackEntry;
+SQLITE_API int sqlite3_busy_handler(
+  sqlite3 *db,
+  int (*xBusy)(void*,int),
+  void *pArg
+){
+  sqlite3_mutex_enter(db->mutex);
+  db->busyHandler.xFunc = xBusy;
+  db->busyHandler.pArg = pArg;
+  db->busyHandler.nBusy = 0;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
 
-/* The state of the parser is completely contained in an instance of
-** the following structure */
-struct yyParser {
-  int yyidx;                    /* Index of top element in stack */
-  int yyerrcnt;                 /* Shifts left before out of the error */
-  sqlite3ParserARG_SDECL                /* A place to hold %extra_argument */
-#if YYSTACKDEPTH<=0
-  int yystksz;                  /* Current side of the stack */
-  yyStackEntry *yystack;        /* The parser's stack */
-#else
-  yyStackEntry yystack[YYSTACKDEPTH];  /* The parser's stack */
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+/*
+** This routine sets the progress callback for an Sqlite database to the
+** given callback function with the given argument. The progress callback will
+** be invoked every nOps opcodes.
+*/
+SQLITE_API void sqlite3_progress_handler(
+  sqlite3 *db, 
+  int nOps,
+  int (*xProgress)(void*), 
+  void *pArg
+){
+  sqlite3_mutex_enter(db->mutex);
+  if( nOps>0 ){
+    db->xProgress = xProgress;
+    db->nProgressOps = nOps;
+    db->pProgressArg = pArg;
+  }else{
+    db->xProgress = 0;
+    db->nProgressOps = 0;
+    db->pProgressArg = 0;
+  }
+  sqlite3_mutex_leave(db->mutex);
+}
 #endif
-};
-typedef struct yyParser yyParser;
 
-#ifndef NDEBUG
-static FILE *yyTraceFILE = 0;
-static char *yyTracePrompt = 0;
-#endif /* NDEBUG */
 
-#ifndef NDEBUG
-/* 
-** Turn parser tracing on by giving a stream to which to write the trace
-** and a prompt to preface each trace message.  Tracing is turned off
-** by making either argument NULL 
-**
-** Inputs:
-** <ul>
-** <li> A FILE* to which trace output should be written.
-**      If NULL, then tracing is turned off.
-** <li> A prefix string written at the beginning of every
-**      line of trace output.  If NULL, then tracing is
-**      turned off.
-** </ul>
-**
-** Outputs:
-** None.
+/*
+** This routine installs a default busy handler that waits for the
+** specified number of milliseconds before returning 0.
 */
-SQLITE_PRIVATE void sqlite3ParserTrace(FILE *TraceFILE, char *zTracePrompt){
-  yyTraceFILE = TraceFILE;
-  yyTracePrompt = zTracePrompt;
-  if( yyTraceFILE==0 ) yyTracePrompt = 0;
-  else if( yyTracePrompt==0 ) yyTraceFILE = 0;
+SQLITE_API int sqlite3_busy_timeout(sqlite3 *db, int ms){
+  if( ms>0 ){
+    db->busyTimeout = ms;
+    sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)db);
+  }else{
+    sqlite3_busy_handler(db, 0, 0);
+  }
+  return SQLITE_OK;
 }
-#endif /* NDEBUG */
-
-#ifndef NDEBUG
-/* For tracing shifts, the names of all terminals and nonterminals
-** are required.  The following table supplies these names */
-static const char *const yyTokenName[] = { 
-  "$",             "SEMI",          "EXPLAIN",       "QUERY",       
-  "PLAN",          "BEGIN",         "TRANSACTION",   "DEFERRED",    
-  "IMMEDIATE",     "EXCLUSIVE",     "COMMIT",        "END",         
-  "ROLLBACK",      "CREATE",        "TABLE",         "IF",          
-  "NOT",           "EXISTS",        "TEMP",          "LP",          
-  "RP",            "AS",            "COMMA",         "ID",          
-  "ABORT",         "AFTER",         "ANALYZE",       "ASC",         
-  "ATTACH",        "BEFORE",        "CASCADE",       "CAST",        
-  "CONFLICT",      "DATABASE",      "DESC",          "DETACH",      
-  "EACH",          "FAIL",          "FOR",           "IGNORE",      
-  "INITIALLY",     "INSTEAD",       "LIKE_KW",       "MATCH",       
-  "KEY",           "OF",            "OFFSET",        "PRAGMA",      
-  "RAISE",         "REPLACE",       "RESTRICT",      "ROW",         
-  "TRIGGER",       "VACUUM",        "VIEW",          "VIRTUAL",     
-  "REINDEX",       "RENAME",        "CTIME_KW",      "ANY",         
-  "OR",            "AND",           "IS",            "BETWEEN",     
-  "IN",            "ISNULL",        "NOTNULL",       "NE",          
-  "EQ",            "GT",            "LE",            "LT",          
-  "GE",            "ESCAPE",        "BITAND",        "BITOR",       
-  "LSHIFT",        "RSHIFT",        "PLUS",          "MINUS",       
-  "STAR",          "SLASH",         "REM",           "CONCAT",      
-  "COLLATE",       "UMINUS",        "UPLUS",         "BITNOT",      
-  "STRING",        "JOIN_KW",       "CONSTRAINT",    "DEFAULT",     
-  "NULL",          "PRIMARY",       "UNIQUE",        "CHECK",       
-  "REFERENCES",    "AUTOINCR",      "ON",            "DELETE",      
-  "UPDATE",        "INSERT",        "SET",           "DEFERRABLE",  
-  "FOREIGN",       "DROP",          "UNION",         "ALL",         
-  "EXCEPT",        "INTERSECT",     "SELECT",        "DISTINCT",    
-  "DOT",           "FROM",          "JOIN",          "USING",       
-  "ORDER",         "BY",            "GROUP",         "HAVING",      
-  "LIMIT",         "WHERE",         "INTO",          "VALUES",      
-  "INTEGER",       "FLOAT",         "BLOB",          "REGISTER",    
-  "VARIABLE",      "CASE",          "WHEN",          "THEN",        
-  "ELSE",          "INDEX",         "ALTER",         "TO",          
-  "ADD",           "COLUMNKW",      "error",         "input",       
-  "cmdlist",       "ecmd",          "cmdx",          "cmd",         
-  "explain",       "transtype",     "trans_opt",     "nm",          
-  "create_table",  "create_table_args",  "temp",          "ifnotexists", 
-  "dbnm",          "columnlist",    "conslist_opt",  "select",      
-  "column",        "columnid",      "type",          "carglist",    
-  "id",            "ids",           "typetoken",     "typename",    
-  "signed",        "plus_num",      "minus_num",     "carg",        
-  "ccons",         "term",          "expr",          "onconf",      
-  "sortorder",     "autoinc",       "idxlist_opt",   "refargs",     
-  "defer_subclause",  "refarg",        "refact",        "init_deferred_pred_opt",
-  "conslist",      "tcons",         "idxlist",       "defer_subclause_opt",
-  "orconf",        "resolvetype",   "raisetype",     "ifexists",    
-  "fullname",      "oneselect",     "multiselect_op",  "distinct",    
-  "selcollist",    "from",          "where_opt",     "groupby_opt", 
-  "having_opt",    "orderby_opt",   "limit_opt",     "sclp",        
-  "as",            "seltablist",    "stl_prefix",    "joinop",      
-  "on_opt",        "using_opt",     "seltablist_paren",  "joinop2",     
-  "inscollist",    "sortlist",      "sortitem",      "nexprlist",   
-  "setlist",       "insert_cmd",    "inscollist_opt",  "itemlist",    
-  "exprlist",      "likeop",        "escape",        "between_op",  
-  "in_op",         "case_operand",  "case_exprlist",  "case_else",   
-  "uniqueflag",    "idxitem",       "collate",       "nmnum",       
-  "plus_opt",      "number",        "trigger_decl",  "trigger_cmd_list",
-  "trigger_time",  "trigger_event",  "foreach_clause",  "when_clause", 
-  "trigger_cmd",   "database_kw_opt",  "key_opt",       "add_column_fullname",
-  "kwcolumn_opt",  "create_vtab",   "vtabarglist",   "vtabarg",     
-  "vtabargtoken",  "lp",            "anylist",     
-};
-#endif /* NDEBUG */
 
-#ifndef NDEBUG
-/* For tracing reduce actions, the names of all rules are required.
+/*
+** Cause any pending operation to stop at its earliest opportunity.
 */
-static const char *const yyRuleName[] = {
- /*   0 */ "input ::= cmdlist",
- /*   1 */ "cmdlist ::= cmdlist ecmd",
- /*   2 */ "cmdlist ::= ecmd",
- /*   3 */ "cmdx ::= cmd",
- /*   4 */ "ecmd ::= SEMI",
- /*   5 */ "ecmd ::= explain cmdx SEMI",
- /*   6 */ "explain ::=",
- /*   7 */ "explain ::= EXPLAIN",
- /*   8 */ "explain ::= EXPLAIN QUERY PLAN",
- /*   9 */ "cmd ::= BEGIN transtype trans_opt",
- /*  10 */ "trans_opt ::=",
- /*  11 */ "trans_opt ::= TRANSACTION",
- /*  12 */ "trans_opt ::= TRANSACTION nm",
- /*  13 */ "transtype ::=",
- /*  14 */ "transtype ::= DEFERRED",
- /*  15 */ "transtype ::= IMMEDIATE",
- /*  16 */ "transtype ::= EXCLUSIVE",
- /*  17 */ "cmd ::= COMMIT trans_opt",
- /*  18 */ "cmd ::= END trans_opt",
- /*  19 */ "cmd ::= ROLLBACK trans_opt",
- /*  20 */ "cmd ::= create_table create_table_args",
- /*  21 */ "create_table ::= CREATE temp TABLE ifnotexists nm dbnm",
- /*  22 */ "ifnotexists ::=",
- /*  23 */ "ifnotexists ::= IF NOT EXISTS",
- /*  24 */ "temp ::= TEMP",
- /*  25 */ "temp ::=",
- /*  26 */ "create_table_args ::= LP columnlist conslist_opt RP",
- /*  27 */ "create_table_args ::= AS select",
- /*  28 */ "columnlist ::= columnlist COMMA column",
- /*  29 */ "columnlist ::= column",
- /*  30 */ "column ::= columnid type carglist",
- /*  31 */ "columnid ::= nm",
- /*  32 */ "id ::= ID",
- /*  33 */ "ids ::= ID|STRING",
- /*  34 */ "nm ::= ID",
- /*  35 */ "nm ::= STRING",
- /*  36 */ "nm ::= JOIN_KW",
- /*  37 */ "type ::=",
- /*  38 */ "type ::= typetoken",
- /*  39 */ "typetoken ::= typename",
- /*  40 */ "typetoken ::= typename LP signed RP",
- /*  41 */ "typetoken ::= typename LP signed COMMA signed RP",
- /*  42 */ "typename ::= ids",
- /*  43 */ "typename ::= typename ids",
- /*  44 */ "signed ::= plus_num",
- /*  45 */ "signed ::= minus_num",
- /*  46 */ "carglist ::= carglist carg",
- /*  47 */ "carglist ::=",
- /*  48 */ "carg ::= CONSTRAINT nm ccons",
- /*  49 */ "carg ::= ccons",
- /*  50 */ "ccons ::= DEFAULT term",
- /*  51 */ "ccons ::= DEFAULT LP expr RP",
- /*  52 */ "ccons ::= DEFAULT PLUS term",
- /*  53 */ "ccons ::= DEFAULT MINUS term",
- /*  54 */ "ccons ::= DEFAULT id",
- /*  55 */ "ccons ::= NULL onconf",
- /*  56 */ "ccons ::= NOT NULL onconf",
- /*  57 */ "ccons ::= PRIMARY KEY sortorder onconf autoinc",
- /*  58 */ "ccons ::= UNIQUE onconf",
- /*  59 */ "ccons ::= CHECK LP expr RP",
- /*  60 */ "ccons ::= REFERENCES nm idxlist_opt refargs",
- /*  61 */ "ccons ::= defer_subclause",
- /*  62 */ "ccons ::= COLLATE ids",
- /*  63 */ "autoinc ::=",
- /*  64 */ "autoinc ::= AUTOINCR",
- /*  65 */ "refargs ::=",
- /*  66 */ "refargs ::= refargs refarg",
- /*  67 */ "refarg ::= MATCH nm",
- /*  68 */ "refarg ::= ON DELETE refact",
- /*  69 */ "refarg ::= ON UPDATE refact",
- /*  70 */ "refarg ::= ON INSERT refact",
- /*  71 */ "refact ::= SET NULL",
- /*  72 */ "refact ::= SET DEFAULT",
- /*  73 */ "refact ::= CASCADE",
- /*  74 */ "refact ::= RESTRICT",
- /*  75 */ "defer_subclause ::= NOT DEFERRABLE init_deferred_pred_opt",
- /*  76 */ "defer_subclause ::= DEFERRABLE init_deferred_pred_opt",
- /*  77 */ "init_deferred_pred_opt ::=",
- /*  78 */ "init_deferred_pred_opt ::= INITIALLY DEFERRED",
- /*  79 */ "init_deferred_pred_opt ::= INITIALLY IMMEDIATE",
- /*  80 */ "conslist_opt ::=",
- /*  81 */ "conslist_opt ::= COMMA conslist",
- /*  82 */ "conslist ::= conslist COMMA tcons",
- /*  83 */ "conslist ::= conslist tcons",
- /*  84 */ "conslist ::= tcons",
- /*  85 */ "tcons ::= CONSTRAINT nm",
- /*  86 */ "tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf",
- /*  87 */ "tcons ::= UNIQUE LP idxlist RP onconf",
- /*  88 */ "tcons ::= CHECK LP expr RP onconf",
- /*  89 */ "tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt",
- /*  90 */ "defer_subclause_opt ::=",
- /*  91 */ "defer_subclause_opt ::= defer_subclause",
- /*  92 */ "onconf ::=",
- /*  93 */ "onconf ::= ON CONFLICT resolvetype",
- /*  94 */ "orconf ::=",
- /*  95 */ "orconf ::= OR resolvetype",
- /*  96 */ "resolvetype ::= raisetype",
- /*  97 */ "resolvetype ::= IGNORE",
- /*  98 */ "resolvetype ::= REPLACE",
- /*  99 */ "cmd ::= DROP TABLE ifexists fullname",
- /* 100 */ "ifexists ::= IF EXISTS",
- /* 101 */ "ifexists ::=",
- /* 102 */ "cmd ::= CREATE temp VIEW ifnotexists nm dbnm AS select",
- /* 103 */ "cmd ::= DROP VIEW ifexists fullname",
- /* 104 */ "cmd ::= select",
- /* 105 */ "select ::= oneselect",
- /* 106 */ "select ::= select multiselect_op oneselect",
- /* 107 */ "multiselect_op ::= UNION",
- /* 108 */ "multiselect_op ::= UNION ALL",
- /* 109 */ "multiselect_op ::= EXCEPT|INTERSECT",
- /* 110 */ "oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt",
- /* 111 */ "distinct ::= DISTINCT",
- /* 112 */ "distinct ::= ALL",
- /* 113 */ "distinct ::=",
- /* 114 */ "sclp ::= selcollist COMMA",
- /* 115 */ "sclp ::=",
- /* 116 */ "selcollist ::= sclp expr as",
- /* 117 */ "selcollist ::= sclp STAR",
- /* 118 */ "selcollist ::= sclp nm DOT STAR",
- /* 119 */ "as ::= AS nm",
- /* 120 */ "as ::= ids",
- /* 121 */ "as ::=",
- /* 122 */ "from ::=",
- /* 123 */ "from ::= FROM seltablist",
- /* 124 */ "stl_prefix ::= seltablist joinop",
- /* 125 */ "stl_prefix ::=",
- /* 126 */ "seltablist ::= stl_prefix nm dbnm as on_opt using_opt",
- /* 127 */ "seltablist ::= stl_prefix LP seltablist_paren RP as on_opt using_opt",
- /* 128 */ "seltablist_paren ::= select",
- /* 129 */ "seltablist_paren ::= seltablist",
- /* 130 */ "dbnm ::=",
- /* 131 */ "dbnm ::= DOT nm",
- /* 132 */ "fullname ::= nm dbnm",
- /* 133 */ "joinop ::= COMMA|JOIN",
- /* 134 */ "joinop ::= JOIN_KW JOIN",
- /* 135 */ "joinop ::= JOIN_KW nm JOIN",
- /* 136 */ "joinop ::= JOIN_KW nm nm JOIN",
- /* 137 */ "on_opt ::= ON expr",
- /* 138 */ "on_opt ::=",
- /* 139 */ "using_opt ::= USING LP inscollist RP",
- /* 140 */ "using_opt ::=",
- /* 141 */ "orderby_opt ::=",
- /* 142 */ "orderby_opt ::= ORDER BY sortlist",
- /* 143 */ "sortlist ::= sortlist COMMA sortitem sortorder",
- /* 144 */ "sortlist ::= sortitem sortorder",
- /* 145 */ "sortitem ::= expr",
- /* 146 */ "sortorder ::= ASC",
- /* 147 */ "sortorder ::= DESC",
- /* 148 */ "sortorder ::=",
- /* 149 */ "groupby_opt ::=",
- /* 150 */ "groupby_opt ::= GROUP BY nexprlist",
- /* 151 */ "having_opt ::=",
- /* 152 */ "having_opt ::= HAVING expr",
- /* 153 */ "limit_opt ::=",
- /* 154 */ "limit_opt ::= LIMIT expr",
- /* 155 */ "limit_opt ::= LIMIT expr OFFSET expr",
- /* 156 */ "limit_opt ::= LIMIT expr COMMA expr",
- /* 157 */ "cmd ::= DELETE FROM fullname where_opt",
- /* 158 */ "where_opt ::=",
- /* 159 */ "where_opt ::= WHERE expr",
- /* 160 */ "cmd ::= UPDATE orconf fullname SET setlist where_opt",
- /* 161 */ "setlist ::= setlist COMMA nm EQ expr",
- /* 162 */ "setlist ::= nm EQ expr",
- /* 163 */ "cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP",
- /* 164 */ "cmd ::= insert_cmd INTO fullname inscollist_opt select",
- /* 165 */ "cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES",
- /* 166 */ "insert_cmd ::= INSERT orconf",
- /* 167 */ "insert_cmd ::= REPLACE",
- /* 168 */ "itemlist ::= itemlist COMMA expr",
- /* 169 */ "itemlist ::= expr",
- /* 170 */ "inscollist_opt ::=",
- /* 171 */ "inscollist_opt ::= LP inscollist RP",
- /* 172 */ "inscollist ::= inscollist COMMA nm",
- /* 173 */ "inscollist ::= nm",
- /* 174 */ "expr ::= term",
- /* 175 */ "expr ::= LP expr RP",
- /* 176 */ "term ::= NULL",
- /* 177 */ "expr ::= ID",
- /* 178 */ "expr ::= JOIN_KW",
- /* 179 */ "expr ::= nm DOT nm",
- /* 180 */ "expr ::= nm DOT nm DOT nm",
- /* 181 */ "term ::= INTEGER|FLOAT|BLOB",
- /* 182 */ "term ::= STRING",
- /* 183 */ "expr ::= REGISTER",
- /* 184 */ "expr ::= VARIABLE",
- /* 185 */ "expr ::= expr COLLATE ids",
- /* 186 */ "expr ::= CAST LP expr AS typetoken RP",
- /* 187 */ "expr ::= ID LP distinct exprlist RP",
- /* 188 */ "expr ::= ID LP STAR RP",
- /* 189 */ "term ::= CTIME_KW",
- /* 190 */ "expr ::= expr AND expr",
- /* 191 */ "expr ::= expr OR expr",
- /* 192 */ "expr ::= expr LT|GT|GE|LE expr",
- /* 193 */ "expr ::= expr EQ|NE expr",
- /* 194 */ "expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr",
- /* 195 */ "expr ::= expr PLUS|MINUS expr",
- /* 196 */ "expr ::= expr STAR|SLASH|REM expr",
- /* 197 */ "expr ::= expr CONCAT expr",
- /* 198 */ "likeop ::= LIKE_KW",
- /* 199 */ "likeop ::= NOT LIKE_KW",
- /* 200 */ "likeop ::= MATCH",
- /* 201 */ "likeop ::= NOT MATCH",
- /* 202 */ "escape ::= ESCAPE expr",
- /* 203 */ "escape ::=",
- /* 204 */ "expr ::= expr likeop expr escape",
- /* 205 */ "expr ::= expr ISNULL|NOTNULL",
- /* 206 */ "expr ::= expr IS NULL",
- /* 207 */ "expr ::= expr NOT NULL",
- /* 208 */ "expr ::= expr IS NOT NULL",
- /* 209 */ "expr ::= NOT expr",
- /* 210 */ "expr ::= BITNOT expr",
- /* 211 */ "expr ::= MINUS expr",
- /* 212 */ "expr ::= PLUS expr",
- /* 213 */ "between_op ::= BETWEEN",
- /* 214 */ "between_op ::= NOT BETWEEN",
- /* 215 */ "expr ::= expr between_op expr AND expr",
- /* 216 */ "in_op ::= IN",
- /* 217 */ "in_op ::= NOT IN",
- /* 218 */ "expr ::= expr in_op LP exprlist RP",
- /* 219 */ "expr ::= LP select RP",
- /* 220 */ "expr ::= expr in_op LP select RP",
- /* 221 */ "expr ::= expr in_op nm dbnm",
- /* 222 */ "expr ::= EXISTS LP select RP",
- /* 223 */ "expr ::= CASE case_operand case_exprlist case_else END",
- /* 224 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
- /* 225 */ "case_exprlist ::= WHEN expr THEN expr",
- /* 226 */ "case_else ::= ELSE expr",
- /* 227 */ "case_else ::=",
- /* 228 */ "case_operand ::= expr",
- /* 229 */ "case_operand ::=",
- /* 230 */ "exprlist ::= nexprlist",
- /* 231 */ "exprlist ::=",
- /* 232 */ "nexprlist ::= nexprlist COMMA expr",
- /* 233 */ "nexprlist ::= expr",
- /* 234 */ "cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
- /* 235 */ "uniqueflag ::= UNIQUE",
- /* 236 */ "uniqueflag ::=",
- /* 237 */ "idxlist_opt ::=",
- /* 238 */ "idxlist_opt ::= LP idxlist RP",
- /* 239 */ "idxlist ::= idxlist COMMA idxitem collate sortorder",
- /* 240 */ "idxlist ::= idxitem collate sortorder",
- /* 241 */ "idxitem ::= nm",
- /* 242 */ "collate ::=",
- /* 243 */ "collate ::= COLLATE ids",
- /* 244 */ "cmd ::= DROP INDEX ifexists fullname",
- /* 245 */ "cmd ::= VACUUM",
- /* 246 */ "cmd ::= VACUUM nm",
- /* 247 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
- /* 248 */ "cmd ::= PRAGMA nm dbnm EQ ON",
- /* 249 */ "cmd ::= PRAGMA nm dbnm EQ DELETE",
- /* 250 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
- /* 251 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
- /* 252 */ "cmd ::= PRAGMA nm dbnm",
- /* 253 */ "nmnum ::= plus_num",
- /* 254 */ "nmnum ::= nm",
- /* 255 */ "plus_num ::= plus_opt number",
- /* 256 */ "minus_num ::= MINUS number",
- /* 257 */ "number ::= INTEGER|FLOAT",
- /* 258 */ "plus_opt ::= PLUS",
- /* 259 */ "plus_opt ::=",
- /* 260 */ "cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END",
- /* 261 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
- /* 262 */ "trigger_time ::= BEFORE",
- /* 263 */ "trigger_time ::= AFTER",
- /* 264 */ "trigger_time ::= INSTEAD OF",
- /* 265 */ "trigger_time ::=",
- /* 266 */ "trigger_event ::= DELETE|INSERT",
- /* 267 */ "trigger_event ::= UPDATE",
- /* 268 */ "trigger_event ::= UPDATE OF inscollist",
- /* 269 */ "foreach_clause ::=",
- /* 270 */ "foreach_clause ::= FOR EACH ROW",
- /* 271 */ "when_clause ::=",
- /* 272 */ "when_clause ::= WHEN expr",
- /* 273 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
- /* 274 */ "trigger_cmd_list ::=",
- /* 275 */ "trigger_cmd ::= UPDATE orconf nm SET setlist where_opt",
- /* 276 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP",
- /* 277 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt select",
- /* 278 */ "trigger_cmd ::= DELETE FROM nm where_opt",
- /* 279 */ "trigger_cmd ::= select",
- /* 280 */ "expr ::= RAISE LP IGNORE RP",
- /* 281 */ "expr ::= RAISE LP raisetype COMMA nm RP",
- /* 282 */ "raisetype ::= ROLLBACK",
- /* 283 */ "raisetype ::= ABORT",
- /* 284 */ "raisetype ::= FAIL",
- /* 285 */ "cmd ::= DROP TRIGGER ifexists fullname",
- /* 286 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
- /* 287 */ "cmd ::= DETACH database_kw_opt expr",
- /* 288 */ "key_opt ::=",
- /* 289 */ "key_opt ::= KEY expr",
- /* 290 */ "database_kw_opt ::= DATABASE",
- /* 291 */ "database_kw_opt ::=",
- /* 292 */ "cmd ::= REINDEX",
- /* 293 */ "cmd ::= REINDEX nm dbnm",
- /* 294 */ "cmd ::= ANALYZE",
- /* 295 */ "cmd ::= ANALYZE nm dbnm",
- /* 296 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
- /* 297 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
- /* 298 */ "add_column_fullname ::= fullname",
- /* 299 */ "kwcolumn_opt ::=",
- /* 300 */ "kwcolumn_opt ::= COLUMNKW",
- /* 301 */ "cmd ::= create_vtab",
- /* 302 */ "cmd ::= create_vtab LP vtabarglist RP",
- /* 303 */ "create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm",
- /* 304 */ "vtabarglist ::= vtabarg",
- /* 305 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
- /* 306 */ "vtabarg ::=",
- /* 307 */ "vtabarg ::= vtabarg vtabargtoken",
- /* 308 */ "vtabargtoken ::= ANY",
- /* 309 */ "vtabargtoken ::= lp anylist RP",
- /* 310 */ "lp ::= LP",
- /* 311 */ "anylist ::=",
- /* 312 */ "anylist ::= anylist ANY",
-};
-#endif /* NDEBUG */
+SQLITE_API void sqlite3_interrupt(sqlite3 *db){
+  db->u1.isInterrupted = 1;
+}
 
 
-#if YYSTACKDEPTH<=0
 /*
-** Try to increase the size of the parser stack.
+** This function is exactly the same as sqlite3_create_function(), except
+** that it is designed to be called by internal code. The difference is
+** that if a malloc() fails in sqlite3_create_function(), an error code
+** is returned and the mallocFailed flag cleared. 
 */
-static void yyGrowStack(yyParser *p){
-  int newSize;
-  yyStackEntry *pNew;
+SQLITE_PRIVATE int sqlite3CreateFunc(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int enc,
+  void *pUserData,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*)
+){
+  FuncDef *p;
+  int nName;
 
-  newSize = p->yystksz*2 + 100;
-  pNew = realloc(p->yystack, newSize*sizeof(pNew[0]));
-  if( pNew ){
-    p->yystack = pNew;
-    p->yystksz = newSize;
-#ifndef NDEBUG
-    if( yyTraceFILE ){
-      fprintf(yyTraceFILE,"%sStack grows to %d entries!\n",
-              yyTracePrompt, p->yystksz);
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( zFunctionName==0 ||
+      (xFunc && (xFinal || xStep)) || 
+      (!xFunc && (xFinal && !xStep)) ||
+      (!xFunc && (!xFinal && xStep)) ||
+      (nArg<-1 || nArg>SQLITE_MAX_FUNCTION_ARG) ||
+      (255<(nName = sqlite3Strlen30( zFunctionName))) ){
+    return SQLITE_MISUSE;
+  }
+  
+#ifndef SQLITE_OMIT_UTF16
+  /* If SQLITE_UTF16 is specified as the encoding type, transform this
+  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
+  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
+  **
+  ** If SQLITE_ANY is specified, add three versions of the function
+  ** to the hash table.
+  */
+  if( enc==SQLITE_UTF16 ){
+    enc = SQLITE_UTF16NATIVE;
+  }else if( enc==SQLITE_ANY ){
+    int rc;
+    rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF8,
+         pUserData, xFunc, xStep, xFinal);
+    if( rc==SQLITE_OK ){
+      rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF16LE,
+          pUserData, xFunc, xStep, xFinal);
+    }
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
+    enc = SQLITE_UTF16BE;
+  }
+#else
+  enc = SQLITE_UTF8;
 #endif
+  
+  /* Check if an existing function is being overridden or deleted. If so,
+  ** and there are active VMs, then return SQLITE_BUSY. If a function
+  ** is being overridden/deleted but there are no active VMs, allow the
+  ** operation to continue but invalidate all precompiled statements.
+  */
+  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 0);
+  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
+    if( db->activeVdbeCnt ){
+      sqlite3Error(db, SQLITE_BUSY, 
+        "unable to delete/modify user-function due to active statements");
+      assert( !db->mallocFailed );
+      return SQLITE_BUSY;
+    }else{
+      sqlite3ExpirePreparedStatements(db);
+    }
+  }
+
+  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 1);
+  assert(p || db->mallocFailed);
+  if( !p ){
+    return SQLITE_NOMEM;
   }
+  p->flags = 0;
+  p->xFunc = xFunc;
+  p->xStep = xStep;
+  p->xFinalize = xFinal;
+  p->pUserData = pUserData;
+  p->nArg = (u16)nArg;
+  return SQLITE_OK;
+}
+
+/*
+** Create new user functions.
+*/
+SQLITE_API int sqlite3_create_function(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int enc,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_API int sqlite3_create_function16(
+  sqlite3 *db,
+  const void *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*)
+){
+  int rc;
+  char *zFunc8;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1);
+  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
+  sqlite3DbFree(db, zFunc8);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 #endif
 
-/* 
-** This function allocates a new parser.
-** The only argument is a pointer to a function which works like
-** malloc.
+
+/*
+** Declare that a function has been overloaded by a virtual table.
 **
-** Inputs:
-** A pointer to the function used to allocate memory.
+** If the function already exists as a regular global function, then
+** this routine is a no-op.  If the function does not exist, then create
+** a new one that always throws a run-time error.  
 **
-** Outputs:
-** A pointer to a parser.  This pointer is used in subsequent calls
-** to sqlite3Parser and sqlite3ParserFree.
+** When virtual tables intend to provide an overloaded function, they
+** should call this routine to make sure the global function exists.
+** A global function must exist in order for name resolution to work
+** properly.
 */
-SQLITE_PRIVATE void *sqlite3ParserAlloc(void *(*mallocProc)(size_t)){
-  yyParser *pParser;
-  pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) );
-  if( pParser ){
-    pParser->yyidx = -1;
-#if YYSTACKDEPTH<=0
-    yyGrowStack(pParser);
-#endif
+SQLITE_API int sqlite3_overload_function(
+  sqlite3 *db,
+  const char *zName,
+  int nArg
+){
+  int nName = sqlite3Strlen30(zName);
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
+    sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
+                      0, sqlite3InvalidFunction, 0, 0);
   }
-  return pParser;
+  rc = sqlite3ApiExit(db, SQLITE_OK);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 
-/* The following function deletes the value associated with a
-** symbol.  The symbol can be either a terminal or nonterminal.
-** "yymajor" is the symbol code, and "yypminor" is a pointer to
-** the value.
+#ifndef SQLITE_OMIT_TRACE
+/*
+** Register a trace function.  The pArg from the previously registered trace
+** is returned.  
+**
+** A NULL trace function means that no tracing is executes.  A non-NULL
+** trace is a pointer to a function that is invoked at the start of each
+** SQL statement.
 */
-static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
-  switch( yymajor ){
-    /* Here is inserted the actions which take place when a
-    ** terminal or non-terminal is destroyed.  This can happen
-    ** when the symbol is popped from the stack during a
-    ** reduce or during error processing or when a parser is 
-    ** being destroyed before it is finished parsing.
-    **
-    ** Note: during a reduce, the only symbols destroyed are those
-    ** which appear on the RHS of the rule, but which are not used
-    ** inside the C code.
-    */
-    case 155: /* select */
-{
-sqlite3SelectDelete((yypminor->yy219));
-}
-      break;
-    case 169: /* term */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 170: /* expr */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 174: /* idxlist_opt */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 182: /* idxlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 188: /* fullname */
-{
-sqlite3SrcListDelete((yypminor->yy373));
-}
-      break;
-    case 189: /* oneselect */
-{
-sqlite3SelectDelete((yypminor->yy219));
-}
-      break;
-    case 192: /* selcollist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 193: /* from */
-{
-sqlite3SrcListDelete((yypminor->yy373));
-}
-      break;
-    case 194: /* where_opt */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 195: /* groupby_opt */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 196: /* having_opt */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 197: /* orderby_opt */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 199: /* sclp */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 201: /* seltablist */
-{
-sqlite3SrcListDelete((yypminor->yy373));
-}
-      break;
-    case 202: /* stl_prefix */
-{
-sqlite3SrcListDelete((yypminor->yy373));
-}
-      break;
-    case 204: /* on_opt */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 205: /* using_opt */
-{
-sqlite3IdListDelete((yypminor->yy432));
-}
-      break;
-    case 206: /* seltablist_paren */
-{
-sqlite3SelectDelete((yypminor->yy219));
-}
-      break;
-    case 208: /* inscollist */
-{
-sqlite3IdListDelete((yypminor->yy432));
-}
-      break;
-    case 209: /* sortlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 210: /* sortitem */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 211: /* nexprlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 212: /* setlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 214: /* inscollist_opt */
-{
-sqlite3IdListDelete((yypminor->yy432));
-}
-      break;
-    case 215: /* itemlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 216: /* exprlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
-}
-      break;
-    case 218: /* escape */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 221: /* case_operand */
-{
-sqlite3ExprDelete((yypminor->yy172));
-}
-      break;
-    case 222: /* case_exprlist */
-{
-sqlite3ExprListDelete((yypminor->yy174));
+SQLITE_API void *sqlite3_trace(sqlite3 *db, void (*xTrace)(void*,const char*), void *pArg){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pTraceArg;
+  db->xTrace = xTrace;
+  db->pTraceArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
 }
-      break;
-    case 223: /* case_else */
-{
-sqlite3ExprDelete((yypminor->yy172));
+/*
+** Register a profile function.  The pArg from the previously registered 
+** profile function is returned.  
+**
+** A NULL profile function means that no profiling is executes.  A non-NULL
+** profile is a pointer to a function that is invoked at the conclusion of
+** each SQL statement that is run.
+*/
+SQLITE_API void *sqlite3_profile(
+  sqlite3 *db,
+  void (*xProfile)(void*,const char*,sqlite_uint64),
+  void *pArg
+){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pProfileArg;
+  db->xProfile = xProfile;
+  db->pProfileArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
 }
-      break;
-    case 231: /* trigger_cmd_list */
-{
-sqlite3DeleteTriggerStep((yypminor->yy243));
+#endif /* SQLITE_OMIT_TRACE */
+
+/*** EXPERIMENTAL ***
+**
+** Register a function to be invoked when a transaction comments.
+** If the invoked function returns non-zero, then the commit becomes a
+** rollback.
+*/
+SQLITE_API void *sqlite3_commit_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  int (*xCallback)(void*),  /* Function to invoke on each commit */
+  void *pArg                /* Argument to the function */
+){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pCommitArg;
+  db->xCommitCallback = xCallback;
+  db->pCommitArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
 }
-      break;
-    case 233: /* trigger_event */
-{
-sqlite3IdListDelete((yypminor->yy370).b);
+
+/*
+** Register a callback to be invoked each time a row is updated,
+** inserted or deleted using this database connection.
+*/
+SQLITE_API void *sqlite3_update_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  void (*xCallback)(void*,int,char const *,char const *,sqlite_int64),
+  void *pArg                /* Argument to the function */
+){
+  void *pRet;
+  sqlite3_mutex_enter(db->mutex);
+  pRet = db->pUpdateArg;
+  db->xUpdateCallback = xCallback;
+  db->pUpdateArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pRet;
 }
-      break;
-    case 235: /* when_clause */
-{
-sqlite3ExprDelete((yypminor->yy172));
+
+/*
+** Register a callback to be invoked each time a transaction is rolled
+** back by this database connection.
+*/
+SQLITE_API void *sqlite3_rollback_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  void (*xCallback)(void*), /* Callback function */
+  void *pArg                /* Argument to the function */
+){
+  void *pRet;
+  sqlite3_mutex_enter(db->mutex);
+  pRet = db->pRollbackArg;
+  db->xRollbackCallback = xCallback;
+  db->pRollbackArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pRet;
 }
-      break;
-    case 236: /* trigger_cmd */
-{
-sqlite3DeleteTriggerStep((yypminor->yy243));
+
+/*
+** This function returns true if main-memory should be used instead of
+** a temporary file for transient pager files and statement journals.
+** The value returned depends on the value of db->temp_store (runtime
+** parameter) and the compile time value of SQLITE_TEMP_STORE. The
+** following table describes the relationship between these two values
+** and this functions return value.
+**
+**   SQLITE_TEMP_STORE     db->temp_store     Location of temporary database
+**   -----------------     --------------     ------------------------------
+**   0                     any                file      (return 0)
+**   1                     1                  file      (return 0)
+**   1                     2                  memory    (return 1)
+**   1                     0                  file      (return 0)
+**   2                     1                  file      (return 0)
+**   2                     2                  memory    (return 1)
+**   2                     0                  memory    (return 1)
+**   3                     any                memory    (return 1)
+*/
+SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3 *db){
+#if SQLITE_TEMP_STORE==1
+  return ( db->temp_store==2 );
+#endif
+#if SQLITE_TEMP_STORE==2
+  return ( db->temp_store!=1 );
+#endif
+#if SQLITE_TEMP_STORE==3
+  return 1;
+#endif
+#if SQLITE_TEMP_STORE<1 || SQLITE_TEMP_STORE>3
+  return 0;
+#endif
 }
-      break;
-    case 238: /* key_opt */
-{
-sqlite3ExprDelete((yypminor->yy172));
+
+/*
+** This routine is called to create a connection to a database BTree
+** driver.  If zFilename is the name of a file, then that file is
+** opened and used.  If zFilename is the magic name ":memory:" then
+** the database is stored in memory (and is thus forgotten as soon as
+** the connection is closed.)  If zFilename is NULL then the database
+** is a "virtual" database for transient use only and is deleted as
+** soon as the connection is closed.
+**
+** A virtual database can be either a disk file (that is automatically
+** deleted when the file is closed) or it an be held entirely in memory.
+** The sqlite3TempInMemory() function is used to determine which.
+*/
+SQLITE_PRIVATE int sqlite3BtreeFactory(
+  const sqlite3 *db,        /* Main database when opening aux otherwise 0 */
+  const char *zFilename,    /* Name of the file containing the BTree database */
+  int omitJournal,          /* if TRUE then do not journal this file */
+  int nCache,               /* How many pages in the page cache */
+  int vfsFlags,             /* Flags passed through to vfsOpen */
+  Btree **ppBtree           /* Pointer to new Btree object written here */
+){
+  int btFlags = 0;
+  int rc;
+  
+  assert( sqlite3_mutex_held(db->mutex) );
+  assert( ppBtree != 0);
+  if( omitJournal ){
+    btFlags |= BTREE_OMIT_JOURNAL;
+  }
+  if( db->flags & SQLITE_NoReadlock ){
+    btFlags |= BTREE_NO_READLOCK;
+  }
+#ifndef SQLITE_OMIT_MEMORYDB
+  if( zFilename==0 && sqlite3TempInMemory(db) ){
+    zFilename = ":memory:";
+  }
+#endif
+
+  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (zFilename==0 || *zFilename==0) ){
+    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
+  }
+  rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
+
+  /* If the B-Tree was successfully opened, set the pager-cache size to the
+  ** default value. Except, if the call to BtreeOpen() returned a handle
+  ** open on an existing shared pager-cache, do not change the pager-cache 
+  ** size.
+  */
+  if( rc==SQLITE_OK && 0==sqlite3BtreeSchema(*ppBtree, 0, 0) ){
+    sqlite3BtreeSetCacheSize(*ppBtree, nCache);
+  }
+  return rc;
 }
-      break;
-    default:  break;   /* If no destructor action specified: do nothing */
+
+/*
+** Return UTF-8 encoded English language explanation of the most recent
+** error.
+*/
+SQLITE_API const char *sqlite3_errmsg(sqlite3 *db){
+  const char *z;
+  if( !db ){
+    return sqlite3ErrStr(SQLITE_NOMEM);
+  }
+  if( !sqlite3SafetyCheckSickOrOk(db) ){
+    return sqlite3ErrStr(SQLITE_MISUSE);
+  }
+  sqlite3_mutex_enter(db->mutex);
+  if( db->mallocFailed ){
+    z = sqlite3ErrStr(SQLITE_NOMEM);
+  }else{
+    z = (char*)sqlite3_value_text(db->pErr);
+    assert( !db->mallocFailed );
+    if( z==0 ){
+      z = sqlite3ErrStr(db->errCode);
+    }
   }
+  sqlite3_mutex_leave(db->mutex);
+  return z;
 }
 
+#ifndef SQLITE_OMIT_UTF16
 /*
-** Pop the parser's stack once.
-**
-** If there is a destructor routine associated with the token which
-** is popped from the stack, then call it.
-**
-** Return the major token number for the symbol popped.
+** Return UTF-16 encoded English language explanation of the most recent
+** error.
 */
-static int yy_pop_parser_stack(yyParser *pParser){
-  YYCODETYPE yymajor;
-  yyStackEntry *yytos = &pParser->yystack[pParser->yyidx];
+SQLITE_API const void *sqlite3_errmsg16(sqlite3 *db){
+  static const u16 outOfMem[] = {
+    'o', 'u', 't', ' ', 'o', 'f', ' ', 'm', 'e', 'm', 'o', 'r', 'y', 0
+  };
+  static const u16 misuse[] = {
+    'l', 'i', 'b', 'r', 'a', 'r', 'y', ' ', 
+    'r', 'o', 'u', 't', 'i', 'n', 'e', ' ', 
+    'c', 'a', 'l', 'l', 'e', 'd', ' ', 
+    'o', 'u', 't', ' ', 
+    'o', 'f', ' ', 
+    's', 'e', 'q', 'u', 'e', 'n', 'c', 'e', 0
+  };
 
-  if( pParser->yyidx<0 ) return 0;
-#ifndef NDEBUG
-  if( yyTraceFILE && pParser->yyidx>=0 ){
-    fprintf(yyTraceFILE,"%sPopping %s\n",
-      yyTracePrompt,
-      yyTokenName[yytos->major]);
+  const void *z;
+  if( !db ){
+    return (void *)outOfMem;
   }
-#endif
-  yymajor = yytos->major;
-  yy_destructor( yymajor, &yytos->minor);
-  pParser->yyidx--;
-  return yymajor;
+  if( !sqlite3SafetyCheckSickOrOk(db) ){
+    return (void *)misuse;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  if( db->mallocFailed ){
+    z = (void *)outOfMem;
+  }else{
+    z = sqlite3_value_text16(db->pErr);
+    if( z==0 ){
+      sqlite3ValueSetStr(db->pErr, -1, sqlite3ErrStr(db->errCode),
+           SQLITE_UTF8, SQLITE_STATIC);
+      z = sqlite3_value_text16(db->pErr);
+    }
+    /* A malloc() may have failed within the call to sqlite3_value_text16()
+    ** above. If this is the case, then the db->mallocFailed flag needs to
+    ** be cleared before returning. Do this directly, instead of via
+    ** sqlite3ApiExit(), to avoid setting the database handle error message.
+    */
+    db->mallocFailed = 0;
+  }
+  sqlite3_mutex_leave(db->mutex);
+  return z;
 }
+#endif /* SQLITE_OMIT_UTF16 */
 
-/* 
-** Deallocate and destroy a parser.  Destructors are all called for
-** all stack elements before shutting the parser down.
-**
-** Inputs:
-** <ul>
-** <li>  A pointer to the parser.  This should be a pointer
-**       obtained from sqlite3ParserAlloc.
-** <li>  A pointer to a function used to reclaim memory obtained
-**       from malloc.
-** </ul>
+/*
+** Return the most recent error code generated by an SQLite routine. If NULL is
+** passed to this function, we assume a malloc() failed during sqlite3_open().
 */
-SQLITE_PRIVATE void sqlite3ParserFree(
-  void *p,                    /* The parser to be deleted */
-  void (*freeProc)(void*)     /* Function used to reclaim memory */
-){
-  yyParser *pParser = (yyParser*)p;
-  if( pParser==0 ) return;
-  while( pParser->yyidx>=0 ) yy_pop_parser_stack(pParser);
-#if YYSTACKDEPTH<=0
-  free(pParser->yystack);
-#endif
-  (*freeProc)((void*)pParser);
+SQLITE_API int sqlite3_errcode(sqlite3 *db){
+  if( db && !sqlite3SafetyCheckSickOrOk(db) ){
+    return SQLITE_MISUSE;
+  }
+  if( !db || db->mallocFailed ){
+    return SQLITE_NOMEM;
+  }
+  return db->errCode & db->errMask;
+}
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db){
+  if( db && !sqlite3SafetyCheckSickOrOk(db) ){
+    return SQLITE_MISUSE;
+  }
+  if( !db || db->mallocFailed ){
+    return SQLITE_NOMEM;
+  }
+  return db->errCode;
 }
 
 /*
-** Find the appropriate action for a parser given the terminal
-** look-ahead token iLookAhead.
-**
-** If the look-ahead token is YYNOCODE, then check to see if the action is
-** independent of the look-ahead.  If it is, return the action, otherwise
-** return YY_NO_ACTION.
+** Create a new collating function for database "db".  The name is zName
+** and the encoding is enc.
 */
-static int yy_find_shift_action(
-  yyParser *pParser,        /* The parser */
-  YYCODETYPE iLookAhead     /* The look-ahead token */
+static int createCollation(
+  sqlite3* db,
+  const char *zName, 
+  u8 enc,
+  u8 collType,
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*),
+  void(*xDel)(void*)
 ){
-  int i;
-  int stateno = pParser->yystack[pParser->yyidx].stateno;
- 
-  if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
-    return yy_default[stateno];
+  CollSeq *pColl;
+  int enc2;
+  int nName = sqlite3Strlen30(zName);
+  
+  assert( sqlite3_mutex_held(db->mutex) );
+
+  /* If SQLITE_UTF16 is specified as the encoding type, transform this
+  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
+  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
+  */
+  enc2 = enc;
+  testcase( enc2==SQLITE_UTF16 );
+  testcase( enc2==SQLITE_UTF16_ALIGNED );
+  if( enc2==SQLITE_UTF16 || enc2==SQLITE_UTF16_ALIGNED ){
+    enc2 = SQLITE_UTF16NATIVE;
   }
-  assert( iLookAhead!=YYNOCODE );
-  i += iLookAhead;
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
-    if( iLookAhead>0 ){
-#ifdef YYFALLBACK
-      int iFallback;            /* Fallback token */
-      if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
-             && (iFallback = yyFallback[iLookAhead])!=0 ){
-#ifndef NDEBUG
-        if( yyTraceFILE ){
-          fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
-             yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
-        }
-#endif
-        return yy_find_shift_action(pParser, iFallback);
-      }
-#endif
-#ifdef YYWILDCARD
-      {
-        int j = i - iLookAhead + YYWILDCARD;
-        if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
-#ifndef NDEBUG
-          if( yyTraceFILE ){
-            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
-               yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]);
+  if( enc2<SQLITE_UTF8 || enc2>SQLITE_UTF16BE ){
+    return SQLITE_MISUSE;
+  }
+
+  /* Check if this call is removing or replacing an existing collation 
+  ** sequence. If so, and there are active VMs, return busy. If there
+  ** are no active VMs, invalidate any pre-compiled statements.
+  */
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 0);
+  if( pColl && pColl->xCmp ){
+    if( db->activeVdbeCnt ){
+      sqlite3Error(db, SQLITE_BUSY, 
+        "unable to delete/modify collation sequence due to active statements");
+      return SQLITE_BUSY;
+    }
+    sqlite3ExpirePreparedStatements(db);
+
+    /* If collation sequence pColl was created directly by a call to
+    ** sqlite3_create_collation, and not generated by synthCollSeq(),
+    ** then any copies made by synthCollSeq() need to be invalidated.
+    ** Also, collation destructor - CollSeq.xDel() - function may need
+    ** to be called.
+    */ 
+    if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
+      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
+      int j;
+      for(j=0; j<3; j++){
+        CollSeq *p = &aColl[j];
+        if( p->enc==pColl->enc ){
+          if( p->xDel ){
+            p->xDel(p->pUser);
           }
-#endif /* NDEBUG */
-          return yy_action[j];
+          p->xCmp = 0;
         }
       }
-#endif /* YYWILDCARD */
     }
-    return yy_default[stateno];
-  }else{
-    return yy_action[i];
   }
+
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 1);
+  if( pColl ){
+    pColl->xCmp = xCompare;
+    pColl->pUser = pCtx;
+    pColl->xDel = xDel;
+    pColl->enc = (u8)(enc2 | (enc & SQLITE_UTF16_ALIGNED));
+    pColl->type = collType;
+  }
+  sqlite3Error(db, SQLITE_OK, 0);
+  return SQLITE_OK;
 }
 
+
 /*
-** Find the appropriate action for a parser given the non-terminal
-** look-ahead token iLookAhead.
-**
-** If the look-ahead token is YYNOCODE, then check to see if the action is
-** independent of the look-ahead.  If it is, return the action, otherwise
-** return YY_NO_ACTION.
+** This array defines hard upper bounds on limit values.  The
+** initializer must be kept in sync with the SQLITE_LIMIT_*
+** #defines in sqlite3.h.
 */
-static int yy_find_reduce_action(
-  int stateno,              /* Current state number */
-  YYCODETYPE iLookAhead     /* The look-ahead token */
-){
-  int i;
-#ifdef YYERRORSYMBOL
-  if( stateno>YY_REDUCE_MAX ){
-    return yy_default[stateno];
-  }
-#else
-  assert( stateno<=YY_REDUCE_MAX );
-#endif
-  i = yy_reduce_ofst[stateno];
-  assert( i!=YY_REDUCE_USE_DFLT );
-  assert( iLookAhead!=YYNOCODE );
-  i += iLookAhead;
-#ifdef YYERRORSYMBOL
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
-    return yy_default[stateno];
-  }
-#else
-  assert( i>=0 && i<YY_SZ_ACTTAB );
-  assert( yy_lookahead[i]==iLookAhead );
-#endif
-  return yy_action[i];
-}
+static const int aHardLimit[] = {
+  SQLITE_MAX_LENGTH,
+  SQLITE_MAX_SQL_LENGTH,
+  SQLITE_MAX_COLUMN,
+  SQLITE_MAX_EXPR_DEPTH,
+  SQLITE_MAX_COMPOUND_SELECT,
+  SQLITE_MAX_VDBE_OP,
+  SQLITE_MAX_FUNCTION_ARG,
+  SQLITE_MAX_ATTACHED,
+  SQLITE_MAX_LIKE_PATTERN_LENGTH,
+  SQLITE_MAX_VARIABLE_NUMBER,
+  SQLITE_MAX_TRIGGER_DEPTH,
+};
 
 /*
-** The following routine is called if the stack overflows.
+** Make sure the hard limits are set to reasonable values
 */
-static void yyStackOverflow(yyParser *yypParser, YYMINORTYPE *yypMinor){
-   sqlite3ParserARG_FETCH;
-   yypParser->yyidx--;
-#ifndef NDEBUG
-   if( yyTraceFILE ){
-     fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt);
-   }
+#if SQLITE_MAX_LENGTH<100
+# error SQLITE_MAX_LENGTH must be at least 100
+#endif
+#if SQLITE_MAX_SQL_LENGTH<100
+# error SQLITE_MAX_SQL_LENGTH must be at least 100
+#endif
+#if SQLITE_MAX_SQL_LENGTH>SQLITE_MAX_LENGTH
+# error SQLITE_MAX_SQL_LENGTH must not be greater than SQLITE_MAX_LENGTH
+#endif
+#if SQLITE_MAX_COMPOUND_SELECT<2
+# error SQLITE_MAX_COMPOUND_SELECT must be at least 2
+#endif
+#if SQLITE_MAX_VDBE_OP<40
+# error SQLITE_MAX_VDBE_OP must be at least 40
+#endif
+#if SQLITE_MAX_FUNCTION_ARG<0 || SQLITE_MAX_FUNCTION_ARG>1000
+# error SQLITE_MAX_FUNCTION_ARG must be between 0 and 1000
+#endif
+#if SQLITE_MAX_ATTACHED<0 || SQLITE_MAX_ATTACHED>30
+# error SQLITE_MAX_ATTACHED must be between 0 and 30
+#endif
+#if SQLITE_MAX_LIKE_PATTERN_LENGTH<1
+# error SQLITE_MAX_LIKE_PATTERN_LENGTH must be at least 1
+#endif
+#if SQLITE_MAX_VARIABLE_NUMBER<1
+# error SQLITE_MAX_VARIABLE_NUMBER must be at least 1
+#endif
+#if SQLITE_MAX_COLUMN>32767
+# error SQLITE_MAX_COLUMN must not exceed 32767
+#endif
+#if SQLITE_MAX_TRIGGER_DEPTH<1
+# error SQLITE_MAX_TRIGGER_DEPTH must be at least 1
 #endif
-   while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
-   /* Here code is inserted which will execute if the parser
-   ** stack every overflows */
 
-  sqlite3ErrorMsg(pParse, "parser stack overflow");
-  pParse->parseError = 1;
-   sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument var */
-}
 
 /*
-** Perform a shift action.
+** Change the value of a limit.  Report the old value.
+** If an invalid limit index is supplied, report -1.
+** Make no changes but still report the old value if the
+** new limit is negative.
+**
+** A new lower limit does not shrink existing constructs.
+** It merely prevents new constructs that exceed the limit
+** from forming.
 */
-static void yy_shift(
-  yyParser *yypParser,          /* The parser to be shifted */
-  int yyNewState,               /* The new state to shift in */
-  int yyMajor,                  /* The major token to shift in */
-  YYMINORTYPE *yypMinor         /* Pointer ot the minor token to shift in */
-){
-  yyStackEntry *yytos;
-  yypParser->yyidx++;
-#if YYSTACKDEPTH>0 
-  if( yypParser->yyidx>=YYSTACKDEPTH ){
-    yyStackOverflow(yypParser, yypMinor);
-    return;
+SQLITE_API int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
+  int oldLimit;
+  if( limitId<0 || limitId>=SQLITE_N_LIMIT ){
+    return -1;
   }
-#else
-  if( yypParser->yyidx>=yypParser->yystksz ){
-    yyGrowStack(yypParser);
-    if( yypParser->yyidx>=yypParser->yystksz ){
-      yyStackOverflow(yypParser, yypMinor);
-      return;
+  oldLimit = db->aLimit[limitId];
+  if( newLimit>=0 ){
+    if( newLimit>aHardLimit[limitId] ){
+      newLimit = aHardLimit[limitId];
     }
+    db->aLimit[limitId] = newLimit;
   }
-#endif
-  yytos = &yypParser->yystack[yypParser->yyidx];
-  yytos->stateno = yyNewState;
-  yytos->major = yyMajor;
-  yytos->minor = *yypMinor;
-#ifndef NDEBUG
-  if( yyTraceFILE && yypParser->yyidx>0 ){
-    int i;
-    fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState);
-    fprintf(yyTraceFILE,"%sStack:",yyTracePrompt);
-    for(i=1; i<=yypParser->yyidx; i++)
-      fprintf(yyTraceFILE," %s",yyTokenName[yypParser->yystack[i].major]);
-    fprintf(yyTraceFILE,"\n");
-  }
-#endif
+  return oldLimit;
 }
 
-/* The following table contains information about every rule that
-** is used during the reduce.
+/*
+** This routine does the work of opening a database on behalf of
+** sqlite3_open() and sqlite3_open16(). The database filename "zFilename"  
+** is UTF-8 encoded.
 */
-static const struct {
-  YYCODETYPE lhs;         /* Symbol on the left-hand side of the rule */
-  unsigned char nrhs;     /* Number of right-hand side symbols in the rule */
-} yyRuleInfo[] = {
-  { 139, 1 },
-  { 140, 2 },
-  { 140, 1 },
-  { 142, 1 },
-  { 141, 1 },
-  { 141, 3 },
-  { 144, 0 },
-  { 144, 1 },
-  { 144, 3 },
-  { 143, 3 },
-  { 146, 0 },
-  { 146, 1 },
-  { 146, 2 },
-  { 145, 0 },
-  { 145, 1 },
-  { 145, 1 },
-  { 145, 1 },
-  { 143, 2 },
-  { 143, 2 },
-  { 143, 2 },
-  { 143, 2 },
-  { 148, 6 },
-  { 151, 0 },
-  { 151, 3 },
-  { 150, 1 },
-  { 150, 0 },
-  { 149, 4 },
-  { 149, 2 },
-  { 153, 3 },
-  { 153, 1 },
-  { 156, 3 },
-  { 157, 1 },
-  { 160, 1 },
-  { 161, 1 },
-  { 147, 1 },
-  { 147, 1 },
-  { 147, 1 },
-  { 158, 0 },
-  { 158, 1 },
-  { 162, 1 },
-  { 162, 4 },
-  { 162, 6 },
-  { 163, 1 },
-  { 163, 2 },
-  { 164, 1 },
-  { 164, 1 },
-  { 159, 2 },
-  { 159, 0 },
-  { 167, 3 },
-  { 167, 1 },
-  { 168, 2 },
-  { 168, 4 },
-  { 168, 3 },
-  { 168, 3 },
-  { 168, 2 },
-  { 168, 2 },
-  { 168, 3 },
-  { 168, 5 },
-  { 168, 2 },
-  { 168, 4 },
-  { 168, 4 },
-  { 168, 1 },
-  { 168, 2 },
-  { 173, 0 },
-  { 173, 1 },
-  { 175, 0 },
-  { 175, 2 },
-  { 177, 2 },
-  { 177, 3 },
-  { 177, 3 },
-  { 177, 3 },
-  { 178, 2 },
-  { 178, 2 },
-  { 178, 1 },
-  { 178, 1 },
-  { 176, 3 },
-  { 176, 2 },
-  { 179, 0 },
-  { 179, 2 },
-  { 179, 2 },
-  { 154, 0 },
-  { 154, 2 },
-  { 180, 3 },
-  { 180, 2 },
-  { 180, 1 },
-  { 181, 2 },
-  { 181, 7 },
-  { 181, 5 },
-  { 181, 5 },
-  { 181, 10 },
-  { 183, 0 },
-  { 183, 1 },
-  { 171, 0 },
-  { 171, 3 },
-  { 184, 0 },
-  { 184, 2 },
-  { 185, 1 },
-  { 185, 1 },
-  { 185, 1 },
-  { 143, 4 },
-  { 187, 2 },
-  { 187, 0 },
-  { 143, 8 },
-  { 143, 4 },
-  { 143, 1 },
-  { 155, 1 },
-  { 155, 3 },
-  { 190, 1 },
-  { 190, 2 },
-  { 190, 1 },
-  { 189, 9 },
-  { 191, 1 },
-  { 191, 1 },
-  { 191, 0 },
-  { 199, 2 },
-  { 199, 0 },
-  { 192, 3 },
-  { 192, 2 },
-  { 192, 4 },
-  { 200, 2 },
-  { 200, 1 },
-  { 200, 0 },
-  { 193, 0 },
-  { 193, 2 },
-  { 202, 2 },
-  { 202, 0 },
-  { 201, 6 },
-  { 201, 7 },
-  { 206, 1 },
-  { 206, 1 },
-  { 152, 0 },
-  { 152, 2 },
-  { 188, 2 },
-  { 203, 1 },
-  { 203, 2 },
-  { 203, 3 },
-  { 203, 4 },
-  { 204, 2 },
-  { 204, 0 },
-  { 205, 4 },
-  { 205, 0 },
-  { 197, 0 },
-  { 197, 3 },
-  { 209, 4 },
-  { 209, 2 },
-  { 210, 1 },
-  { 172, 1 },
-  { 172, 1 },
-  { 172, 0 },
-  { 195, 0 },
-  { 195, 3 },
-  { 196, 0 },
-  { 196, 2 },
-  { 198, 0 },
-  { 198, 2 },
-  { 198, 4 },
-  { 198, 4 },
-  { 143, 4 },
-  { 194, 0 },
-  { 194, 2 },
-  { 143, 6 },
-  { 212, 5 },
-  { 212, 3 },
-  { 143, 8 },
-  { 143, 5 },
-  { 143, 6 },
-  { 213, 2 },
-  { 213, 1 },
-  { 215, 3 },
-  { 215, 1 },
-  { 214, 0 },
-  { 214, 3 },
-  { 208, 3 },
-  { 208, 1 },
-  { 170, 1 },
-  { 170, 3 },
-  { 169, 1 },
-  { 170, 1 },
-  { 170, 1 },
-  { 170, 3 },
-  { 170, 5 },
-  { 169, 1 },
-  { 169, 1 },
-  { 170, 1 },
-  { 170, 1 },
-  { 170, 3 },
-  { 170, 6 },
-  { 170, 5 },
-  { 170, 4 },
-  { 169, 1 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 217, 1 },
-  { 217, 2 },
-  { 217, 1 },
-  { 217, 2 },
-  { 218, 2 },
-  { 218, 0 },
-  { 170, 4 },
-  { 170, 2 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 4 },
-  { 170, 2 },
-  { 170, 2 },
-  { 170, 2 },
-  { 170, 2 },
-  { 219, 1 },
-  { 219, 2 },
-  { 170, 5 },
-  { 220, 1 },
-  { 220, 2 },
-  { 170, 5 },
-  { 170, 3 },
-  { 170, 5 },
-  { 170, 4 },
-  { 170, 4 },
-  { 170, 5 },
-  { 222, 5 },
-  { 222, 4 },
-  { 223, 2 },
-  { 223, 0 },
-  { 221, 1 },
-  { 221, 0 },
-  { 216, 1 },
-  { 216, 0 },
-  { 211, 3 },
-  { 211, 1 },
-  { 143, 11 },
-  { 224, 1 },
-  { 224, 0 },
-  { 174, 0 },
-  { 174, 3 },
-  { 182, 5 },
-  { 182, 3 },
-  { 225, 1 },
-  { 226, 0 },
-  { 226, 2 },
-  { 143, 4 },
-  { 143, 1 },
-  { 143, 2 },
-  { 143, 5 },
-  { 143, 5 },
-  { 143, 5 },
-  { 143, 5 },
-  { 143, 6 },
-  { 143, 3 },
-  { 227, 1 },
-  { 227, 1 },
-  { 165, 2 },
-  { 166, 2 },
-  { 229, 1 },
-  { 228, 1 },
-  { 228, 0 },
-  { 143, 5 },
-  { 230, 11 },
-  { 232, 1 },
-  { 232, 1 },
-  { 232, 2 },
-  { 232, 0 },
-  { 233, 1 },
-  { 233, 1 },
-  { 233, 3 },
-  { 234, 0 },
-  { 234, 3 },
-  { 235, 0 },
-  { 235, 2 },
-  { 231, 3 },
-  { 231, 0 },
-  { 236, 6 },
-  { 236, 8 },
-  { 236, 5 },
-  { 236, 4 },
-  { 236, 1 },
-  { 170, 4 },
-  { 170, 6 },
-  { 186, 1 },
-  { 186, 1 },
-  { 186, 1 },
-  { 143, 4 },
-  { 143, 6 },
-  { 143, 3 },
-  { 238, 0 },
-  { 238, 2 },
-  { 237, 1 },
-  { 237, 0 },
-  { 143, 1 },
-  { 143, 3 },
-  { 143, 1 },
-  { 143, 3 },
-  { 143, 6 },
-  { 143, 6 },
-  { 239, 1 },
-  { 240, 0 },
-  { 240, 1 },
-  { 143, 1 },
-  { 143, 4 },
-  { 241, 7 },
-  { 242, 1 },
-  { 242, 3 },
-  { 243, 0 },
-  { 243, 2 },
-  { 244, 1 },
-  { 244, 3 },
-  { 245, 1 },
-  { 246, 0 },
-  { 246, 2 },
-};
+static int openDatabase(
+  const char *zFilename, /* Database filename UTF-8 encoded */
+  sqlite3 **ppDb,        /* OUT: Returned database handle */
+  unsigned flags,        /* Operational flags */
+  const char *zVfs       /* Name of the VFS to use */
+){
+  sqlite3 *db;
+  int rc;
+  int isThreadsafe;
+
+  *ppDb = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
+
+  if( sqlite3GlobalConfig.bCoreMutex==0 ){
+    isThreadsafe = 0;
+  }else if( flags & SQLITE_OPEN_NOMUTEX ){
+    isThreadsafe = 0;
+  }else if( flags & SQLITE_OPEN_FULLMUTEX ){
+    isThreadsafe = 1;
+  }else{
+    isThreadsafe = sqlite3GlobalConfig.bFullMutex;
+  }
+  if( flags & SQLITE_OPEN_PRIVATECACHE ){
+    flags &= ~SQLITE_OPEN_SHAREDCACHE;
+  }else if( sqlite3GlobalConfig.sharedCacheEnabled ){
+    flags |= SQLITE_OPEN_SHAREDCACHE;
+  }
+
+  /* Remove harmful bits from the flags parameter
+  **
+  ** The SQLITE_OPEN_NOMUTEX and SQLITE_OPEN_FULLMUTEX flags were
+  ** dealt with in the previous code block.  Besides these, the only
+  ** valid input flags for sqlite3_open_v2() are SQLITE_OPEN_READONLY,
+  ** SQLITE_OPEN_READWRITE, and SQLITE_OPEN_CREATE.  Silently mask
+  ** off all other flags.
+  */
+  flags &=  ~( SQLITE_OPEN_DELETEONCLOSE |
+               SQLITE_OPEN_EXCLUSIVE |
+               SQLITE_OPEN_MAIN_DB |
+               SQLITE_OPEN_TEMP_DB | 
+               SQLITE_OPEN_TRANSIENT_DB | 
+               SQLITE_OPEN_MAIN_JOURNAL | 
+               SQLITE_OPEN_TEMP_JOURNAL | 
+               SQLITE_OPEN_SUBJOURNAL | 
+               SQLITE_OPEN_MASTER_JOURNAL |
+               SQLITE_OPEN_NOMUTEX |
+               SQLITE_OPEN_FULLMUTEX
+             );
 
-static void yy_accept(yyParser*);  /* Forward Declaration */
+  /* Allocate the sqlite data structure */
+  db = sqlite3MallocZero( sizeof(sqlite3) );
+  if( db==0 ) goto opendb_out;
+  if( isThreadsafe ){
+    db->mutex = sqlite3MutexAlloc(SQLITE_MUTEX_RECURSIVE);
+    if( db->mutex==0 ){
+      sqlite3_free(db);
+      db = 0;
+      goto opendb_out;
+    }
+  }
+  sqlite3_mutex_enter(db->mutex);
+  db->errMask = 0xff;
+  db->nDb = 2;
+  db->magic = SQLITE_MAGIC_BUSY;
+  db->aDb = db->aDbStatic;
 
-/*
-** Perform a reduce action and the shift that must immediately
-** follow the reduce.
-*/
-static void yy_reduce(
-  yyParser *yypParser,         /* The parser */
-  int yyruleno                 /* Number of the rule by which to reduce */
-){
-  int yygoto;                     /* The next state */
-  int yyact;                      /* The next action */
-  YYMINORTYPE yygotominor;        /* The LHS of the rule reduced */
-  yyStackEntry *yymsp;            /* The top of the parser's stack */
-  int yysize;                     /* Amount to pop the stack */
-  sqlite3ParserARG_FETCH;
-  yymsp = &yypParser->yystack[yypParser->yyidx];
-#ifndef NDEBUG
-  if( yyTraceFILE && yyruleno>=0 
-        && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
-    fprintf(yyTraceFILE, "%sReduce [%s].\n", yyTracePrompt,
-      yyRuleName[yyruleno]);
+  assert( sizeof(db->aLimit)==sizeof(aHardLimit) );
+  memcpy(db->aLimit, aHardLimit, sizeof(db->aLimit));
+  db->autoCommit = 1;
+  db->nextAutovac = -1;
+  db->nextPagesize = 0;
+  db->flags |= SQLITE_ShortColNames
+#if SQLITE_DEFAULT_FILE_FORMAT<4
+                 | SQLITE_LegacyFileFmt
+#endif
+#ifdef SQLITE_ENABLE_LOAD_EXTENSION
+                 | SQLITE_LoadExtension
+#endif
+#if SQLITE_DEFAULT_RECURSIVE_TRIGGERS
+                 | SQLITE_RecTriggers
+#endif
+      ;
+  sqlite3HashInit(&db->aCollSeq);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3HashInit(&db->aModule);
+#endif
+
+  db->pVfs = sqlite3_vfs_find(zVfs);
+  if( !db->pVfs ){
+    rc = SQLITE_ERROR;
+    sqlite3Error(db, rc, "no such vfs: %s", zVfs);
+    goto opendb_out;
   }
-#endif /* NDEBUG */
 
-  /* Silence complaints from purify about yygotominor being uninitialized
-  ** in some cases when it is copied into the stack after the following
-  ** switch.  yygotominor is uninitialized when a rule reduces that does
-  ** not set the value of its left-hand side nonterminal.  Leaving the
-  ** value of the nonterminal uninitialized is utterly harmless as long
-  ** as the value is never used.  So really the only thing this code
-  ** accomplishes is to quieten purify.  
-  **
-  ** 2007-01-16:  The wireshark project (www.wireshark.org) reports that
-  ** without this code, their parser segfaults.  I'm not sure what there
-  ** parser is doing to make this happen.  This is the second bug report
-  ** from wireshark this week.  Clearly they are stressing Lemon in ways
-  ** that it has not been previously stressed...  (SQLite ticket #2172)
+  /* Add the default collation sequence BINARY. BINARY works for both UTF-8
+  ** and UTF-16, so add a version for each to avoid any unnecessary
+  ** conversions. The only error that can occur here is a malloc() failure.
   */
-  /*memset(&yygotominor, 0, sizeof(yygotominor));*/
-  yygotominor = yyzerominor;
+  createCollation(db, "BINARY", SQLITE_UTF8, SQLITE_COLL_BINARY, 0,
+                  binCollFunc, 0);
+  createCollation(db, "BINARY", SQLITE_UTF16BE, SQLITE_COLL_BINARY, 0,
+                  binCollFunc, 0);
+  createCollation(db, "BINARY", SQLITE_UTF16LE, SQLITE_COLL_BINARY, 0,
+                  binCollFunc, 0);
+  createCollation(db, "RTRIM", SQLITE_UTF8, SQLITE_COLL_USER, (void*)1,
+                  binCollFunc, 0);
+  if( db->mallocFailed ){
+    goto opendb_out;
+  }
+  db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 0);
+  assert( db->pDfltColl!=0 );
 
+  /* Also add a UTF-8 case-insensitive collation sequence. */
+  createCollation(db, "NOCASE", SQLITE_UTF8, SQLITE_COLL_NOCASE, 0,
+                  nocaseCollatingFunc, 0);
 
-  switch( yyruleno ){
-  /* Beginning here are the reduction cases.  A typical example
-  ** follows:
-  **   case 0:
-  **  #line <lineno> <grammarfile>
-  **     { ... }           // User supplied code
-  **  #line <lineno> <thisfile>
-  **     break;
+  /* Open the backend database driver */
+  db->openFlags = flags;
+  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE, 
+                           flags | SQLITE_OPEN_MAIN_DB,
+                           &db->aDb[0].pBt);
+  if( rc!=SQLITE_OK ){
+    if( rc==SQLITE_IOERR_NOMEM ){
+      rc = SQLITE_NOMEM;
+    }
+    sqlite3Error(db, rc, 0);
+    goto opendb_out;
+  }
+  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
+  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);
+
+
+  /* The default safety_level for the main database is 'full'; for the temp
+  ** database it is 'NONE'. This matches the pager layer defaults.  
   */
-      case 0: /* input ::= cmdlist */
-      case 1: /* cmdlist ::= cmdlist ecmd */
-      case 2: /* cmdlist ::= ecmd */
-      case 4: /* ecmd ::= SEMI */
-      case 5: /* ecmd ::= explain cmdx SEMI */
-      case 10: /* trans_opt ::= */
-      case 11: /* trans_opt ::= TRANSACTION */
-      case 12: /* trans_opt ::= TRANSACTION nm */
-      case 20: /* cmd ::= create_table create_table_args */
-      case 28: /* columnlist ::= columnlist COMMA column */
-      case 29: /* columnlist ::= column */
-      case 37: /* type ::= */
-      case 44: /* signed ::= plus_num */
-      case 45: /* signed ::= minus_num */
-      case 46: /* carglist ::= carglist carg */
-      case 47: /* carglist ::= */
-      case 48: /* carg ::= CONSTRAINT nm ccons */
-      case 49: /* carg ::= ccons */
-      case 55: /* ccons ::= NULL onconf */
-      case 82: /* conslist ::= conslist COMMA tcons */
-      case 83: /* conslist ::= conslist tcons */
-      case 84: /* conslist ::= tcons */
-      case 85: /* tcons ::= CONSTRAINT nm */
-      case 258: /* plus_opt ::= PLUS */
-      case 259: /* plus_opt ::= */
-      case 269: /* foreach_clause ::= */
-      case 270: /* foreach_clause ::= FOR EACH ROW */
-      case 290: /* database_kw_opt ::= DATABASE */
-      case 291: /* database_kw_opt ::= */
-      case 299: /* kwcolumn_opt ::= */
-      case 300: /* kwcolumn_opt ::= COLUMNKW */
-      case 304: /* vtabarglist ::= vtabarg */
-      case 305: /* vtabarglist ::= vtabarglist COMMA vtabarg */
-      case 307: /* vtabarg ::= vtabarg vtabargtoken */
-      case 311: /* anylist ::= */
-{
-}
-        break;
-      case 3: /* cmdx ::= cmd */
-{ sqlite3FinishCoding(pParse); }
-        break;
-      case 6: /* explain ::= */
-{ sqlite3BeginParse(pParse, 0); }
-        break;
-      case 7: /* explain ::= EXPLAIN */
-{ sqlite3BeginParse(pParse, 1); }
-        break;
-      case 8: /* explain ::= EXPLAIN QUERY PLAN */
-{ sqlite3BeginParse(pParse, 2); }
-        break;
-      case 9: /* cmd ::= BEGIN transtype trans_opt */
-{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy46);}
-        break;
-      case 13: /* transtype ::= */
-{yygotominor.yy46 = TK_DEFERRED;}
-        break;
-      case 14: /* transtype ::= DEFERRED */
-      case 15: /* transtype ::= IMMEDIATE */
-      case 16: /* transtype ::= EXCLUSIVE */
-      case 107: /* multiselect_op ::= UNION */
-      case 109: /* multiselect_op ::= EXCEPT|INTERSECT */
-{yygotominor.yy46 = yymsp[0].major;}
-        break;
-      case 17: /* cmd ::= COMMIT trans_opt */
-      case 18: /* cmd ::= END trans_opt */
-{sqlite3CommitTransaction(pParse);}
-        break;
-      case 19: /* cmd ::= ROLLBACK trans_opt */
-{sqlite3RollbackTransaction(pParse);}
-        break;
-      case 21: /* create_table ::= CREATE temp TABLE ifnotexists nm dbnm */
-{
-   sqlite3StartTable(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410,yymsp[-4].minor.yy46,0,0,yymsp[-2].minor.yy46);
-}
-        break;
-      case 22: /* ifnotexists ::= */
-      case 25: /* temp ::= */
-      case 63: /* autoinc ::= */
-      case 77: /* init_deferred_pred_opt ::= */
-      case 79: /* init_deferred_pred_opt ::= INITIALLY IMMEDIATE */
-      case 90: /* defer_subclause_opt ::= */
-      case 101: /* ifexists ::= */
-      case 112: /* distinct ::= ALL */
-      case 113: /* distinct ::= */
-      case 213: /* between_op ::= BETWEEN */
-      case 216: /* in_op ::= IN */
-{yygotominor.yy46 = 0;}
-        break;
-      case 23: /* ifnotexists ::= IF NOT EXISTS */
-      case 24: /* temp ::= TEMP */
-      case 64: /* autoinc ::= AUTOINCR */
-      case 78: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */
-      case 100: /* ifexists ::= IF EXISTS */
-      case 111: /* distinct ::= DISTINCT */
-      case 214: /* between_op ::= NOT BETWEEN */
-      case 217: /* in_op ::= NOT IN */
-{yygotominor.yy46 = 1;}
-        break;
-      case 26: /* create_table_args ::= LP columnlist conslist_opt RP */
-{
-  sqlite3EndTable(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy0,0);
-}
-        break;
-      case 27: /* create_table_args ::= AS select */
-{
-  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy219);
-  sqlite3SelectDelete(yymsp[0].minor.yy219);
-}
-        break;
-      case 30: /* column ::= columnid type carglist */
-{
-  yygotominor.yy410.z = yymsp[-2].minor.yy410.z;
-  yygotominor.yy410.n = (pParse->sLastToken.z-yymsp[-2].minor.yy410.z) + pParse->sLastToken.n;
-}
-        break;
-      case 31: /* columnid ::= nm */
-{
-  sqlite3AddColumn(pParse,&yymsp[0].minor.yy410);
-  yygotominor.yy410 = yymsp[0].minor.yy410;
-}
-        break;
-      case 32: /* id ::= ID */
-      case 33: /* ids ::= ID|STRING */
-      case 34: /* nm ::= ID */
-      case 35: /* nm ::= STRING */
-      case 36: /* nm ::= JOIN_KW */
-      case 257: /* number ::= INTEGER|FLOAT */
-{yygotominor.yy410 = yymsp[0].minor.yy0;}
-        break;
-      case 38: /* type ::= typetoken */
-{sqlite3AddColumnType(pParse,&yymsp[0].minor.yy410);}
-        break;
-      case 39: /* typetoken ::= typename */
-      case 42: /* typename ::= ids */
-      case 119: /* as ::= AS nm */
-      case 120: /* as ::= ids */
-      case 131: /* dbnm ::= DOT nm */
-      case 241: /* idxitem ::= nm */
-      case 243: /* collate ::= COLLATE ids */
-      case 253: /* nmnum ::= plus_num */
-      case 254: /* nmnum ::= nm */
-      case 255: /* plus_num ::= plus_opt number */
-      case 256: /* minus_num ::= MINUS number */
-{yygotominor.yy410 = yymsp[0].minor.yy410;}
-        break;
-      case 40: /* typetoken ::= typename LP signed RP */
-{
-  yygotominor.yy410.z = yymsp[-3].minor.yy410.z;
-  yygotominor.yy410.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-3].minor.yy410.z;
-}
-        break;
-      case 41: /* typetoken ::= typename LP signed COMMA signed RP */
-{
-  yygotominor.yy410.z = yymsp[-5].minor.yy410.z;
-  yygotominor.yy410.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-5].minor.yy410.z;
-}
-        break;
-      case 43: /* typename ::= typename ids */
-{yygotominor.yy410.z=yymsp[-1].minor.yy410.z; yygotominor.yy410.n=yymsp[0].minor.yy410.n+(yymsp[0].minor.yy410.z-yymsp[-1].minor.yy410.z);}
-        break;
-      case 50: /* ccons ::= DEFAULT term */
-      case 52: /* ccons ::= DEFAULT PLUS term */
-{sqlite3AddDefaultValue(pParse,yymsp[0].minor.yy172);}
-        break;
-      case 51: /* ccons ::= DEFAULT LP expr RP */
-{sqlite3AddDefaultValue(pParse,yymsp[-1].minor.yy172);}
-        break;
-      case 53: /* ccons ::= DEFAULT MINUS term */
-{
-  Expr *p = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy172, 0, 0);
-  sqlite3AddDefaultValue(pParse,p);
-}
-        break;
-      case 54: /* ccons ::= DEFAULT id */
-{
-  Expr *p = sqlite3PExpr(pParse, TK_STRING, 0, 0, &yymsp[0].minor.yy410);
-  sqlite3AddDefaultValue(pParse,p);
-}
-        break;
-      case 56: /* ccons ::= NOT NULL onconf */
-{sqlite3AddNotNull(pParse, yymsp[0].minor.yy46);}
-        break;
-      case 57: /* ccons ::= PRIMARY KEY sortorder onconf autoinc */
-{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy46,yymsp[0].minor.yy46,yymsp[-2].minor.yy46);}
-        break;
-      case 58: /* ccons ::= UNIQUE onconf */
-{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy46,0,0,0,0);}
-        break;
-      case 59: /* ccons ::= CHECK LP expr RP */
-{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy172);}
-        break;
-      case 60: /* ccons ::= REFERENCES nm idxlist_opt refargs */
-{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy410,yymsp[-1].minor.yy174,yymsp[0].minor.yy46);}
-        break;
-      case 61: /* ccons ::= defer_subclause */
-{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy46);}
-        break;
-      case 62: /* ccons ::= COLLATE ids */
-{sqlite3AddCollateType(pParse, &yymsp[0].minor.yy410);}
-        break;
-      case 65: /* refargs ::= */
-{ yygotominor.yy46 = OE_Restrict * 0x010101; }
-        break;
-      case 66: /* refargs ::= refargs refarg */
-{ yygotominor.yy46 = (yymsp[-1].minor.yy46 & yymsp[0].minor.yy405.mask) | yymsp[0].minor.yy405.value; }
-        break;
-      case 67: /* refarg ::= MATCH nm */
-{ yygotominor.yy405.value = 0;     yygotominor.yy405.mask = 0x000000; }
-        break;
-      case 68: /* refarg ::= ON DELETE refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46;     yygotominor.yy405.mask = 0x0000ff; }
-        break;
-      case 69: /* refarg ::= ON UPDATE refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46<<8;  yygotominor.yy405.mask = 0x00ff00; }
-        break;
-      case 70: /* refarg ::= ON INSERT refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46<<16; yygotominor.yy405.mask = 0xff0000; }
-        break;
-      case 71: /* refact ::= SET NULL */
-{ yygotominor.yy46 = OE_SetNull; }
-        break;
-      case 72: /* refact ::= SET DEFAULT */
-{ yygotominor.yy46 = OE_SetDflt; }
-        break;
-      case 73: /* refact ::= CASCADE */
-{ yygotominor.yy46 = OE_Cascade; }
-        break;
-      case 74: /* refact ::= RESTRICT */
-{ yygotominor.yy46 = OE_Restrict; }
-        break;
-      case 75: /* defer_subclause ::= NOT DEFERRABLE init_deferred_pred_opt */
-      case 76: /* defer_subclause ::= DEFERRABLE init_deferred_pred_opt */
-      case 91: /* defer_subclause_opt ::= defer_subclause */
-      case 93: /* onconf ::= ON CONFLICT resolvetype */
-      case 95: /* orconf ::= OR resolvetype */
-      case 96: /* resolvetype ::= raisetype */
-      case 166: /* insert_cmd ::= INSERT orconf */
-{yygotominor.yy46 = yymsp[0].minor.yy46;}
-        break;
-      case 80: /* conslist_opt ::= */
-{yygotominor.yy410.n = 0; yygotominor.yy410.z = 0;}
-        break;
-      case 81: /* conslist_opt ::= COMMA conslist */
-{yygotominor.yy410 = yymsp[-1].minor.yy0;}
-        break;
-      case 86: /* tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf */
-{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy174,yymsp[0].minor.yy46,yymsp[-2].minor.yy46,0);}
-        break;
-      case 87: /* tcons ::= UNIQUE LP idxlist RP onconf */
-{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy174,yymsp[0].minor.yy46,0,0,0,0);}
-        break;
-      case 88: /* tcons ::= CHECK LP expr RP onconf */
-{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy172);}
-        break;
-      case 89: /* tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt */
-{
-    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy174, &yymsp[-3].minor.yy410, yymsp[-2].minor.yy174, yymsp[-1].minor.yy46);
-    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy46);
-}
-        break;
-      case 92: /* onconf ::= */
-      case 94: /* orconf ::= */
-{yygotominor.yy46 = OE_Default;}
-        break;
-      case 97: /* resolvetype ::= IGNORE */
-{yygotominor.yy46 = OE_Ignore;}
-        break;
-      case 98: /* resolvetype ::= REPLACE */
-      case 167: /* insert_cmd ::= REPLACE */
-{yygotominor.yy46 = OE_Replace;}
-        break;
-      case 99: /* cmd ::= DROP TABLE ifexists fullname */
-{
-  sqlite3DropTable(pParse, yymsp[0].minor.yy373, 0, yymsp[-1].minor.yy46);
-}
-        break;
-      case 102: /* cmd ::= CREATE temp VIEW ifnotexists nm dbnm AS select */
-{
-  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy410, &yymsp[-2].minor.yy410, yymsp[0].minor.yy219, yymsp[-6].minor.yy46, yymsp[-4].minor.yy46);
-}
-        break;
-      case 103: /* cmd ::= DROP VIEW ifexists fullname */
-{
-  sqlite3DropTable(pParse, yymsp[0].minor.yy373, 1, yymsp[-1].minor.yy46);
-}
-        break;
-      case 104: /* cmd ::= select */
-{
-  SelectDest dest = {SRT_Callback, 0, 0, 0, 0};
-  sqlite3Select(pParse, yymsp[0].minor.yy219, &dest, 0, 0, 0, 0);
-  sqlite3SelectDelete(yymsp[0].minor.yy219);
-}
-        break;
-      case 105: /* select ::= oneselect */
-      case 128: /* seltablist_paren ::= select */
-{yygotominor.yy219 = yymsp[0].minor.yy219;}
-        break;
-      case 106: /* select ::= select multiselect_op oneselect */
-{
-  if( yymsp[0].minor.yy219 ){
-    yymsp[0].minor.yy219->op = yymsp[-1].minor.yy46;
-    yymsp[0].minor.yy219->pPrior = yymsp[-2].minor.yy219;
-  }else{
-    sqlite3SelectDelete(yymsp[-2].minor.yy219);
+  db->aDb[0].zName = "main";
+  db->aDb[0].safety_level = 3;
+  db->aDb[1].zName = "temp";
+  db->aDb[1].safety_level = 1;
+
+  db->magic = SQLITE_MAGIC_OPEN;
+  if( db->mallocFailed ){
+    goto opendb_out;
   }
-  yygotominor.yy219 = yymsp[0].minor.yy219;
-}
-        break;
-      case 108: /* multiselect_op ::= UNION ALL */
-{yygotominor.yy46 = TK_ALL;}
-        break;
-      case 110: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
-{
-  yygotominor.yy219 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy174,yymsp[-5].minor.yy373,yymsp[-4].minor.yy172,yymsp[-3].minor.yy174,yymsp[-2].minor.yy172,yymsp[-1].minor.yy174,yymsp[-7].minor.yy46,yymsp[0].minor.yy234.pLimit,yymsp[0].minor.yy234.pOffset);
-}
-        break;
-      case 114: /* sclp ::= selcollist COMMA */
-      case 238: /* idxlist_opt ::= LP idxlist RP */
-{yygotominor.yy174 = yymsp[-1].minor.yy174;}
-        break;
-      case 115: /* sclp ::= */
-      case 141: /* orderby_opt ::= */
-      case 149: /* groupby_opt ::= */
-      case 231: /* exprlist ::= */
-      case 237: /* idxlist_opt ::= */
-{yygotominor.yy174 = 0;}
-        break;
-      case 116: /* selcollist ::= sclp expr as */
-{
-   yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy174,yymsp[-1].minor.yy172,yymsp[0].minor.yy410.n?&yymsp[0].minor.yy410:0);
-}
-        break;
-      case 117: /* selcollist ::= sclp STAR */
-{
-  Expr *p = sqlite3PExpr(pParse, TK_ALL, 0, 0, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy174, p, 0);
-}
-        break;
-      case 118: /* selcollist ::= sclp nm DOT STAR */
-{
-  Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, 0);
-  Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
-  Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy174, pDot, 0);
-}
-        break;
-      case 121: /* as ::= */
-{yygotominor.yy410.n = 0;}
-        break;
-      case 122: /* from ::= */
-{yygotominor.yy373 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy373));}
-        break;
-      case 123: /* from ::= FROM seltablist */
-{
-  yygotominor.yy373 = yymsp[0].minor.yy373;
-  sqlite3SrcListShiftJoinType(yygotominor.yy373);
-}
-        break;
-      case 124: /* stl_prefix ::= seltablist joinop */
-{
-   yygotominor.yy373 = yymsp[-1].minor.yy373;
-   if( yygotominor.yy373 && yygotominor.yy373->nSrc>0 ) yygotominor.yy373->a[yygotominor.yy373->nSrc-1].jointype = yymsp[0].minor.yy46;
-}
-        break;
-      case 125: /* stl_prefix ::= */
-{yygotominor.yy373 = 0;}
-        break;
-      case 126: /* seltablist ::= stl_prefix nm dbnm as on_opt using_opt */
-{
-  yygotominor.yy373 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-5].minor.yy373,&yymsp[-4].minor.yy410,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,0,yymsp[-1].minor.yy172,yymsp[0].minor.yy432);
-}
-        break;
-      case 127: /* seltablist ::= stl_prefix LP seltablist_paren RP as on_opt using_opt */
-{
-    yygotominor.yy373 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy373,0,0,&yymsp[-2].minor.yy410,yymsp[-4].minor.yy219,yymsp[-1].minor.yy172,yymsp[0].minor.yy432);
+
+  /* Register all built-in functions, but do not attempt to read the
+  ** database schema yet. This is delayed until the first time the database
+  ** is accessed.
+  */
+  sqlite3Error(db, SQLITE_OK, 0);
+  sqlite3RegisterBuiltinFunctions(db);
+
+  /* Load automatic extensions - extensions that have been registered
+  ** using the sqlite3_automatic_extension() API.
+  */
+  sqlite3AutoLoadExtensions(db);
+  rc = sqlite3_errcode(db);
+  if( rc!=SQLITE_OK ){
+    goto opendb_out;
   }
-        break;
-      case 129: /* seltablist_paren ::= seltablist */
-{
-     sqlite3SrcListShiftJoinType(yymsp[0].minor.yy373);
-     yygotominor.yy219 = sqlite3SelectNew(pParse,0,yymsp[0].minor.yy373,0,0,0,0,0,0,0);
+
+#ifdef SQLITE_ENABLE_FTS1
+  if( !db->mallocFailed ){
+    extern int sqlite3Fts1Init(sqlite3*);
+    rc = sqlite3Fts1Init(db);
   }
-        break;
-      case 130: /* dbnm ::= */
-{yygotominor.yy410.z=0; yygotominor.yy410.n=0;}
-        break;
-      case 132: /* fullname ::= nm dbnm */
-{yygotominor.yy373 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410);}
-        break;
-      case 133: /* joinop ::= COMMA|JOIN */
-{ yygotominor.yy46 = JT_INNER; }
-        break;
-      case 134: /* joinop ::= JOIN_KW JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
-        break;
-      case 135: /* joinop ::= JOIN_KW nm JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy410,0); }
-        break;
-      case 136: /* joinop ::= JOIN_KW nm nm JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy410,&yymsp[-1].minor.yy410); }
-        break;
-      case 137: /* on_opt ::= ON expr */
-      case 145: /* sortitem ::= expr */
-      case 152: /* having_opt ::= HAVING expr */
-      case 159: /* where_opt ::= WHERE expr */
-      case 174: /* expr ::= term */
-      case 202: /* escape ::= ESCAPE expr */
-      case 226: /* case_else ::= ELSE expr */
-      case 228: /* case_operand ::= expr */
-{yygotominor.yy172 = yymsp[0].minor.yy172;}
-        break;
-      case 138: /* on_opt ::= */
-      case 151: /* having_opt ::= */
-      case 158: /* where_opt ::= */
-      case 203: /* escape ::= */
-      case 227: /* case_else ::= */
-      case 229: /* case_operand ::= */
-{yygotominor.yy172 = 0;}
-        break;
-      case 139: /* using_opt ::= USING LP inscollist RP */
-      case 171: /* inscollist_opt ::= LP inscollist RP */
-{yygotominor.yy432 = yymsp[-1].minor.yy432;}
-        break;
-      case 140: /* using_opt ::= */
-      case 170: /* inscollist_opt ::= */
-{yygotominor.yy432 = 0;}
-        break;
-      case 142: /* orderby_opt ::= ORDER BY sortlist */
-      case 150: /* groupby_opt ::= GROUP BY nexprlist */
-      case 230: /* exprlist ::= nexprlist */
-{yygotominor.yy174 = yymsp[0].minor.yy174;}
-        break;
-      case 143: /* sortlist ::= sortlist COMMA sortitem sortorder */
-{
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy174,yymsp[-1].minor.yy172,0);
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
-}
-        break;
-      case 144: /* sortlist ::= sortitem sortorder */
-{
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy172,0);
-  if( yygotominor.yy174 && yygotominor.yy174->a ) yygotominor.yy174->a[0].sortOrder = yymsp[0].minor.yy46;
-}
-        break;
-      case 146: /* sortorder ::= ASC */
-      case 148: /* sortorder ::= */
-{yygotominor.yy46 = SQLITE_SO_ASC;}
-        break;
-      case 147: /* sortorder ::= DESC */
-{yygotominor.yy46 = SQLITE_SO_DESC;}
-        break;
-      case 153: /* limit_opt ::= */
-{yygotominor.yy234.pLimit = 0; yygotominor.yy234.pOffset = 0;}
-        break;
-      case 154: /* limit_opt ::= LIMIT expr */
-{yygotominor.yy234.pLimit = yymsp[0].minor.yy172; yygotominor.yy234.pOffset = 0;}
-        break;
-      case 155: /* limit_opt ::= LIMIT expr OFFSET expr */
-{yygotominor.yy234.pLimit = yymsp[-2].minor.yy172; yygotominor.yy234.pOffset = yymsp[0].minor.yy172;}
-        break;
-      case 156: /* limit_opt ::= LIMIT expr COMMA expr */
-{yygotominor.yy234.pOffset = yymsp[-2].minor.yy172; yygotominor.yy234.pLimit = yymsp[0].minor.yy172;}
-        break;
-      case 157: /* cmd ::= DELETE FROM fullname where_opt */
-{sqlite3DeleteFrom(pParse,yymsp[-1].minor.yy373,yymsp[0].minor.yy172);}
-        break;
-      case 160: /* cmd ::= UPDATE orconf fullname SET setlist where_opt */
-{
-  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy174,"set list"); 
-  sqlite3Update(pParse,yymsp[-3].minor.yy373,yymsp[-1].minor.yy174,yymsp[0].minor.yy172,yymsp[-4].minor.yy46);
-}
-        break;
-      case 161: /* setlist ::= setlist COMMA nm EQ expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174,yymsp[0].minor.yy172,&yymsp[-2].minor.yy410);}
-        break;
-      case 162: /* setlist ::= nm EQ expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy172,&yymsp[-2].minor.yy410);}
-        break;
-      case 163: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
-{sqlite3Insert(pParse, yymsp[-5].minor.yy373, yymsp[-1].minor.yy174, 0, yymsp[-4].minor.yy432, yymsp[-7].minor.yy46);}
-        break;
-      case 164: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
-{sqlite3Insert(pParse, yymsp[-2].minor.yy373, 0, yymsp[0].minor.yy219, yymsp[-1].minor.yy432, yymsp[-4].minor.yy46);}
-        break;
-      case 165: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
-{sqlite3Insert(pParse, yymsp[-3].minor.yy373, 0, 0, yymsp[-2].minor.yy432, yymsp[-5].minor.yy46);}
-        break;
-      case 168: /* itemlist ::= itemlist COMMA expr */
-      case 232: /* nexprlist ::= nexprlist COMMA expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy174,yymsp[0].minor.yy172,0);}
-        break;
-      case 169: /* itemlist ::= expr */
-      case 233: /* nexprlist ::= expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy172,0);}
-        break;
-      case 172: /* inscollist ::= inscollist COMMA nm */
-{yygotominor.yy432 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy432,&yymsp[0].minor.yy410);}
-        break;
-      case 173: /* inscollist ::= nm */
-{yygotominor.yy432 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy410);}
-        break;
-      case 175: /* expr ::= LP expr RP */
-{yygotominor.yy172 = yymsp[-1].minor.yy172; sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0); }
-        break;
-      case 176: /* term ::= NULL */
-      case 181: /* term ::= INTEGER|FLOAT|BLOB */
-      case 182: /* term ::= STRING */
-{yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[0].major, 0, 0, &yymsp[0].minor.yy0);}
-        break;
-      case 177: /* expr ::= ID */
-      case 178: /* expr ::= JOIN_KW */
-{yygotominor.yy172 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);}
-        break;
-      case 179: /* expr ::= nm DOT nm */
-{
-  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
-  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy410);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
-}
-        break;
-      case 180: /* expr ::= nm DOT nm DOT nm */
-{
-  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-4].minor.yy410);
-  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
-  Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy410);
-  Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
-}
-        break;
-      case 183: /* expr ::= REGISTER */
-{yygotominor.yy172 = sqlite3RegisterExpr(pParse, &yymsp[0].minor.yy0);}
-        break;
-      case 184: /* expr ::= VARIABLE */
-{
-  Token *pToken = &yymsp[0].minor.yy0;
-  Expr *pExpr = yygotominor.yy172 = sqlite3PExpr(pParse, TK_VARIABLE, 0, 0, pToken);
-  sqlite3ExprAssignVarNumber(pParse, pExpr);
-}
-        break;
-      case 185: /* expr ::= expr COLLATE ids */
-{
-  yygotominor.yy172 = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy172, &yymsp[0].minor.yy410);
-}
-        break;
-      case 186: /* expr ::= CAST LP expr AS typetoken RP */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy172, 0, &yymsp[-1].minor.yy410);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
-}
-        break;
-      case 187: /* expr ::= ID LP distinct exprlist RP */
-{
-  if( yymsp[-1].minor.yy174 && yymsp[-1].minor.yy174->nExpr>SQLITE_MAX_FUNCTION_ARG ){
-    sqlite3ErrorMsg(pParse, "too many arguments on function %T", &yymsp[-4].minor.yy0);
+#endif
+
+#ifdef SQLITE_ENABLE_FTS2
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    extern int sqlite3Fts2Init(sqlite3*);
+    rc = sqlite3Fts2Init(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_FTS3
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    rc = sqlite3Fts3Init(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_ICU
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    rc = sqlite3IcuInit(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_RTREE
+  if( !db->mallocFailed && rc==SQLITE_OK){
+    rc = sqlite3RtreeInit(db);
   }
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy174, &yymsp[-4].minor.yy0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
-  if( yymsp[-2].minor.yy46 && yygotominor.yy172 ){
-    yygotominor.yy172->flags |= EP_Distinct;
+#endif
+
+  sqlite3Error(db, rc, 0);
+
+  /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
+  ** mode.  -DSQLITE_DEFAULT_LOCKING_MODE=0 make NORMAL the default locking
+  ** mode.  Doing nothing at all also makes NORMAL the default.
+  */
+#ifdef SQLITE_DEFAULT_LOCKING_MODE
+  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
+  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
+                          SQLITE_DEFAULT_LOCKING_MODE);
+#endif
+
+  /* Enable the lookaside-malloc subsystem */
+  setupLookaside(db, 0, sqlite3GlobalConfig.szLookaside,
+                        sqlite3GlobalConfig.nLookaside);
+
+opendb_out:
+  if( db ){
+    assert( db->mutex!=0 || isThreadsafe==0 || sqlite3GlobalConfig.bFullMutex==0 );
+    sqlite3_mutex_leave(db->mutex);
+  }
+  rc = sqlite3_errcode(db);
+  if( rc==SQLITE_NOMEM ){
+    sqlite3_close(db);
+    db = 0;
+  }else if( rc!=SQLITE_OK ){
+    db->magic = SQLITE_MAGIC_SICK;
   }
+  *ppDb = db;
+  return sqlite3ApiExit(0, rc);
 }
-        break;
-      case 188: /* expr ::= ID LP STAR RP */
-{
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
+
+/*
+** Open a new database handle.
+*/
+SQLITE_API int sqlite3_open(
+  const char *zFilename, 
+  sqlite3 **ppDb 
+){
+  return openDatabase(zFilename, ppDb,
+                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
 }
-        break;
-      case 189: /* term ::= CTIME_KW */
-{
-  /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
-  ** treated as functions that return constants */
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->op = TK_CONST_FUNC;  
-    yygotominor.yy172->span = yymsp[0].minor.yy0;
-  }
+SQLITE_API int sqlite3_open_v2(
+  const char *filename,   /* Database filename (UTF-8) */
+  sqlite3 **ppDb,         /* OUT: SQLite db handle */
+  int flags,              /* Flags */
+  const char *zVfs        /* Name of VFS module to use */
+){
+  return openDatabase(filename, ppDb, flags, zVfs);
 }
-        break;
-      case 190: /* expr ::= expr AND expr */
-      case 191: /* expr ::= expr OR expr */
-      case 192: /* expr ::= expr LT|GT|GE|LE expr */
-      case 193: /* expr ::= expr EQ|NE expr */
-      case 194: /* expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr */
-      case 195: /* expr ::= expr PLUS|MINUS expr */
-      case 196: /* expr ::= expr STAR|SLASH|REM expr */
-      case 197: /* expr ::= expr CONCAT expr */
-{yygotominor.yy172 = sqlite3PExpr(pParse,yymsp[-1].major,yymsp[-2].minor.yy172,yymsp[0].minor.yy172,0);}
-        break;
-      case 198: /* likeop ::= LIKE_KW */
-      case 200: /* likeop ::= MATCH */
-{yygotominor.yy72.eOperator = yymsp[0].minor.yy0; yygotominor.yy72.not = 0;}
-        break;
-      case 199: /* likeop ::= NOT LIKE_KW */
-      case 201: /* likeop ::= NOT MATCH */
-{yygotominor.yy72.eOperator = yymsp[0].minor.yy0; yygotominor.yy72.not = 1;}
-        break;
-      case 204: /* expr ::= expr likeop expr escape */
-{
-  ExprList *pList;
-  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy172, 0);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy172, 0);
-  if( yymsp[0].minor.yy172 ){
-    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy172, 0);
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Open a new database handle.
+*/
+SQLITE_API int sqlite3_open16(
+  const void *zFilename, 
+  sqlite3 **ppDb
+){
+  char const *zFilename8;   /* zFilename encoded in UTF-8 instead of UTF-16 */
+  sqlite3_value *pVal;
+  int rc;
+
+  assert( zFilename );
+  assert( ppDb );
+  *ppDb = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
+  pVal = sqlite3ValueNew(0);
+  sqlite3ValueSetStr(pVal, -1, zFilename, SQLITE_UTF16NATIVE, SQLITE_STATIC);
+  zFilename8 = sqlite3ValueText(pVal, SQLITE_UTF8);
+  if( zFilename8 ){
+    rc = openDatabase(zFilename8, ppDb,
+                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
+    assert( *ppDb || rc==SQLITE_NOMEM );
+    if( rc==SQLITE_OK && !DbHasProperty(*ppDb, 0, DB_SchemaLoaded) ){
+      ENC(*ppDb) = SQLITE_UTF16NATIVE;
+    }
+  }else{
+    rc = SQLITE_NOMEM;
   }
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy72.eOperator);
-  if( yymsp[-2].minor.yy72.not ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172, &yymsp[-3].minor.yy172->span, &yymsp[-1].minor.yy172->span);
-  if( yygotominor.yy172 ) yygotominor.yy172->flags |= EP_InfixFunc;
+  sqlite3ValueFree(pVal);
+
+  return sqlite3ApiExit(0, rc);
 }
-        break;
-      case 205: /* expr ::= expr ISNULL|NOTNULL */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[0].major, yymsp[-1].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy172->span,&yymsp[0].minor.yy0);
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** Register a new collation sequence with the database handle db.
+*/
+SQLITE_API int sqlite3_create_collation(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  rc = createCollation(db, zName, (u8)enc, SQLITE_COLL_USER, pCtx, xCompare, 0);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
-        break;
-      case 206: /* expr ::= expr IS NULL */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_ISNULL, yymsp[-2].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy172->span,&yymsp[0].minor.yy0);
+
+/*
+** Register a new collation sequence with the database handle db.
+*/
+SQLITE_API int sqlite3_create_collation_v2(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*),
+  void(*xDel)(void*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  rc = createCollation(db, zName, (u8)enc, SQLITE_COLL_USER, pCtx, xCompare, xDel);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
-        break;
-      case 207: /* expr ::= expr NOT NULL */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-2].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy172->span,&yymsp[0].minor.yy0);
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Register a new collation sequence with the database handle db.
+*/
+SQLITE_API int sqlite3_create_collation16(
+  sqlite3* db, 
+  const void *zName,
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+){
+  int rc = SQLITE_OK;
+  char *zName8;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  zName8 = sqlite3Utf16to8(db, zName, -1);
+  if( zName8 ){
+    rc = createCollation(db, zName8, (u8)enc, SQLITE_COLL_USER, pCtx, xCompare, 0);
+    sqlite3DbFree(db, zName8);
+  }
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** Register a collation sequence factory callback with the database handle
+** db. Replace any previously installed collation sequence factory.
+*/
+SQLITE_API int sqlite3_collation_needed(
+  sqlite3 *db, 
+  void *pCollNeededArg, 
+  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*)
+){
+  sqlite3_mutex_enter(db->mutex);
+  db->xCollNeeded = xCollNeeded;
+  db->xCollNeeded16 = 0;
+  db->pCollNeededArg = pCollNeededArg;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
 }
-        break;
-      case 208: /* expr ::= expr IS NOT NULL */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-3].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy172->span,&yymsp[0].minor.yy0);
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Register a collation sequence factory callback with the database handle
+** db. Replace any previously installed collation sequence factory.
+*/
+SQLITE_API int sqlite3_collation_needed16(
+  sqlite3 *db, 
+  void *pCollNeededArg, 
+  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*)
+){
+  sqlite3_mutex_enter(db->mutex);
+  db->xCollNeeded = 0;
+  db->xCollNeeded16 = xCollNeeded16;
+  db->pCollNeededArg = pCollNeededArg;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
 }
-        break;
-      case 209: /* expr ::= NOT expr */
-      case 210: /* expr ::= BITNOT expr */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[-1].major, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+#endif /* SQLITE_OMIT_UTF16 */
+
+#ifndef SQLITE_OMIT_GLOBALRECOVER
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** This function is now an anachronism. It used to be used to recover from a
+** malloc() failure, but SQLite now does this automatically.
+*/
+SQLITE_API int sqlite3_global_recover(void){
+  return SQLITE_OK;
 }
-        break;
-      case 211: /* expr ::= MINUS expr */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+#endif
+#endif
+
+/*
+** Test to see whether or not the database connection is in autocommit
+** mode.  Return TRUE if it is and FALSE if not.  Autocommit mode is on
+** by default.  Autocommit is disabled by a BEGIN statement and reenabled
+** by the next COMMIT or ROLLBACK.
+**
+******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
+*/
+SQLITE_API int sqlite3_get_autocommit(sqlite3 *db){
+  return db->autoCommit;
 }
-        break;
-      case 212: /* expr ::= PLUS expr */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_UPLUS, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+
+#ifdef SQLITE_DEBUG
+/*
+** The following routine is subtituted for constant SQLITE_CORRUPT in
+** debugging builds.  This provides a way to set a breakpoint for when
+** corruption is first detected.
+*/
+SQLITE_PRIVATE int sqlite3Corrupt(void){
+  return SQLITE_CORRUPT;
 }
-        break;
-      case 215: /* expr ::= expr between_op expr AND expr */
-{
-  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy172, 0);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy172, 0);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy172, 0, 0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->pList = pList;
-  }else{
-    sqlite3ExprListDelete(pList);
-  } 
-  if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy172->span);
+#endif
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** This is a convenience routine that makes sure that all thread-specific
+** data for this thread has been deallocated.
+**
+** SQLite no longer uses thread-specific data so this routine is now a
+** no-op.  It is retained for historical compatibility.
+*/
+SQLITE_API void sqlite3_thread_cleanup(void){
 }
-        break;
-      case 218: /* expr ::= expr in_op LP exprlist RP */
-{
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pList = yymsp[-1].minor.yy174;
-      sqlite3ExprSetHeight(yygotominor.yy172);
-    }else{
-      sqlite3ExprListDelete(yymsp[-1].minor.yy174);
-    }
-    if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy0);
+#endif
+
+/*
+** Return meta information about a specific column of a database table.
+** See comment in sqlite3.h (sqlite.h.in) for details.
+*/
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+SQLITE_API int sqlite3_table_column_metadata(
+  sqlite3 *db,                /* Connection handle */
+  const char *zDbName,        /* Database name or NULL */
+  const char *zTableName,     /* Table name */
+  const char *zColumnName,    /* Column name */
+  char const **pzDataType,    /* OUTPUT: Declared data type */
+  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
+  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
+  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
+  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
+){
+  int rc;
+  char *zErrMsg = 0;
+  Table *pTab = 0;
+  Column *pCol = 0;
+  int iCol;
+
+  char const *zDataType = 0;
+  char const *zCollSeq = 0;
+  int notnull = 0;
+  int primarykey = 0;
+  int autoinc = 0;
+
+  /* Ensure the database schema has been loaded */
+  sqlite3_mutex_enter(db->mutex);
+  (void)sqlite3SafetyOn(db);
+  sqlite3BtreeEnterAll(db);
+  rc = sqlite3Init(db, &zErrMsg);
+  if( SQLITE_OK!=rc ){
+    goto error_out;
   }
-        break;
-      case 219: /* expr ::= LP select RP */
-{
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = yymsp[-1].minor.yy219;
-      sqlite3ExprSetHeight(yygotominor.yy172);
-    }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
-    }
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
+
+  /* Locate the table in question */
+  pTab = sqlite3FindTable(db, zTableName, zDbName);
+  if( !pTab || pTab->pSelect ){
+    pTab = 0;
+    goto error_out;
   }
-        break;
-      case 220: /* expr ::= expr in_op LP select RP */
-{
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = yymsp[-1].minor.yy219;
-      sqlite3ExprSetHeight(yygotominor.yy172);
-    }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
+
+  /* Find the column for which info is requested */
+  if( sqlite3IsRowid(zColumnName) ){
+    iCol = pTab->iPKey;
+    if( iCol>=0 ){
+      pCol = &pTab->aCol[iCol];
     }
-    if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy0);
-  }
+  }else{
+    for(iCol=0; iCol<pTab->nCol; iCol++){
+      pCol = &pTab->aCol[iCol];
+      if( 0==sqlite3StrICmp(pCol->zName, zColumnName) ){
         break;
-      case 221: /* expr ::= expr in_op nm dbnm */
-{
-    SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410);
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
-      sqlite3ExprSetHeight(yygotominor.yy172);
-    }else{
-      sqlite3SrcListDelete(pSrc);
+      }
     }
-    if( yymsp[-2].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy172->span,yymsp[0].minor.yy410.z?&yymsp[0].minor.yy410:&yymsp[-1].minor.yy410);
-  }
-        break;
-      case 222: /* expr ::= EXISTS LP select RP */
-{
-    Expr *p = yygotominor.yy172 = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
-    if( p ){
-      p->pSelect = yymsp[-1].minor.yy219;
-      sqlite3ExprSpan(p,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
-      sqlite3ExprSetHeight(yygotominor.yy172);
-    }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
+    if( iCol==pTab->nCol ){
+      pTab = 0;
+      goto error_out;
     }
   }
-        break;
-      case 223: /* expr ::= CASE case_operand case_exprlist case_else END */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy172, yymsp[-1].minor.yy172, 0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->pList = yymsp[-2].minor.yy174;
-    sqlite3ExprSetHeight(yygotominor.yy172);
+
+  /* The following block stores the meta information that will be returned
+  ** to the caller in local variables zDataType, zCollSeq, notnull, primarykey
+  ** and autoinc. At this point there are two possibilities:
+  ** 
+  **     1. The specified column name was rowid", "oid" or "_rowid_" 
+  **        and there is no explicitly declared IPK column. 
+  **
+  **     2. The table is not a view and the column name identified an 
+  **        explicitly declared column. Copy meta information from *pCol.
+  */ 
+  if( pCol ){
+    zDataType = pCol->zType;
+    zCollSeq = pCol->zColl;
+    notnull = pCol->notNull!=0;
+    primarykey  = pCol->isPrimKey!=0;
+    autoinc = pTab->iPKey==iCol && (pTab->tabFlags & TF_Autoincrement)!=0;
   }else{
-    sqlite3ExprListDelete(yymsp[-2].minor.yy174);
+    zDataType = "INTEGER";
+    primarykey = 1;
   }
-  sqlite3ExprSpan(yygotominor.yy172, &yymsp[-4].minor.yy0, &yymsp[0].minor.yy0);
-}
-        break;
-      case 224: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
-{
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174, yymsp[-2].minor.yy172, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yygotominor.yy174, yymsp[0].minor.yy172, 0);
-}
-        break;
-      case 225: /* case_exprlist ::= WHEN expr THEN expr */
-{
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy172, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yygotominor.yy174, yymsp[0].minor.yy172, 0);
-}
-        break;
-      case 234: /* cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
-{
-  sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy410, &yymsp[-5].minor.yy410, 
-                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy410,0), yymsp[-1].minor.yy174, yymsp[-9].minor.yy46,
-                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy46);
-}
-        break;
-      case 235: /* uniqueflag ::= UNIQUE */
-      case 283: /* raisetype ::= ABORT */
-{yygotominor.yy46 = OE_Abort;}
-        break;
-      case 236: /* uniqueflag ::= */
-{yygotominor.yy46 = OE_None;}
-        break;
-      case 239: /* idxlist ::= idxlist COMMA idxitem collate sortorder */
-{
-  Expr *p = 0;
-  if( yymsp[-1].minor.yy410.n>0 ){
-    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy410);
+  if( !zCollSeq ){
+    zCollSeq = "BINARY";
   }
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174, p, &yymsp[-2].minor.yy410);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy174, "index");
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
-}
-        break;
-      case 240: /* idxlist ::= idxitem collate sortorder */
-{
-  Expr *p = 0;
-  if( yymsp[-1].minor.yy410.n>0 ){
-    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy410);
+
+error_out:
+  sqlite3BtreeLeaveAll(db);
+  (void)sqlite3SafetyOff(db);
+
+  /* Whether the function call succeeded or failed, set the output parameters
+  ** to whatever their local counterparts contain. If an error did occur,
+  ** this has the effect of zeroing all output parameters.
+  */
+  if( pzDataType ) *pzDataType = zDataType;
+  if( pzCollSeq ) *pzCollSeq = zCollSeq;
+  if( pNotNull ) *pNotNull = notnull;
+  if( pPrimaryKey ) *pPrimaryKey = primarykey;
+  if( pAutoinc ) *pAutoinc = autoinc;
+
+  if( SQLITE_OK==rc && !pTab ){
+    sqlite3DbFree(db, zErrMsg);
+    zErrMsg = sqlite3MPrintf(db, "no such table column: %s.%s", zTableName,
+        zColumnName);
+    rc = SQLITE_ERROR;
   }
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0, p, &yymsp[-2].minor.yy410);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy174, "index");
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
-}
-        break;
-      case 242: /* collate ::= */
-{yygotominor.yy410.z = 0; yygotominor.yy410.n = 0;}
-        break;
-      case 244: /* cmd ::= DROP INDEX ifexists fullname */
-{sqlite3DropIndex(pParse, yymsp[0].minor.yy373, yymsp[-1].minor.yy46);}
-        break;
-      case 245: /* cmd ::= VACUUM */
-      case 246: /* cmd ::= VACUUM nm */
-{sqlite3Vacuum(pParse);}
-        break;
-      case 247: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
-{sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy410,0);}
-        break;
-      case 248: /* cmd ::= PRAGMA nm dbnm EQ ON */
-      case 249: /* cmd ::= PRAGMA nm dbnm EQ DELETE */
-{sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy0,0);}
-        break;
-      case 250: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
-{
-  sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy410,1);
+  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
+  sqlite3DbFree(db, zErrMsg);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
-        break;
-      case 251: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
-{sqlite3Pragma(pParse,&yymsp[-4].minor.yy410,&yymsp[-3].minor.yy410,&yymsp[-1].minor.yy410,0);}
-        break;
-      case 252: /* cmd ::= PRAGMA nm dbnm */
-{sqlite3Pragma(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410,0,0);}
-        break;
-      case 260: /* cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END */
-{
-  Token all;
-  all.z = yymsp[-3].minor.yy410.z;
-  all.n = (yymsp[0].minor.yy0.z - yymsp[-3].minor.yy410.z) + yymsp[0].minor.yy0.n;
-  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy243, &all);
+#endif
+
+/*
+** Sleep for a little while.  Return the amount of time slept.
+*/
+SQLITE_API int sqlite3_sleep(int ms){
+  sqlite3_vfs *pVfs;
+  int rc;
+  pVfs = sqlite3_vfs_find(0);
+  if( pVfs==0 ) return 0;
+
+  /* This function works in milliseconds, but the underlying OsSleep() 
+  ** API uses microseconds. Hence the 1000's.
+  */
+  rc = (sqlite3OsSleep(pVfs, 1000*ms)/1000);
+  return rc;
 }
-        break;
-      case 261: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
-{
-  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy410, &yymsp[-6].minor.yy410, yymsp[-5].minor.yy46, yymsp[-4].minor.yy370.a, yymsp[-4].minor.yy370.b, yymsp[-2].minor.yy373, yymsp[0].minor.yy172, yymsp[-10].minor.yy46, yymsp[-8].minor.yy46);
-  yygotominor.yy410 = (yymsp[-6].minor.yy410.n==0?yymsp[-7].minor.yy410:yymsp[-6].minor.yy410);
+
+/*
+** Enable or disable the extended result codes.
+*/
+SQLITE_API int sqlite3_extended_result_codes(sqlite3 *db, int onoff){
+  sqlite3_mutex_enter(db->mutex);
+  db->errMask = onoff ? 0xffffffff : 0xff;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
 }
-        break;
-      case 262: /* trigger_time ::= BEFORE */
-      case 265: /* trigger_time ::= */
-{ yygotominor.yy46 = TK_BEFORE; }
-        break;
-      case 263: /* trigger_time ::= AFTER */
-{ yygotominor.yy46 = TK_AFTER;  }
-        break;
-      case 264: /* trigger_time ::= INSTEAD OF */
-{ yygotominor.yy46 = TK_INSTEAD;}
-        break;
-      case 266: /* trigger_event ::= DELETE|INSERT */
-      case 267: /* trigger_event ::= UPDATE */
-{yygotominor.yy370.a = yymsp[0].major; yygotominor.yy370.b = 0;}
-        break;
-      case 268: /* trigger_event ::= UPDATE OF inscollist */
-{yygotominor.yy370.a = TK_UPDATE; yygotominor.yy370.b = yymsp[0].minor.yy432;}
-        break;
-      case 271: /* when_clause ::= */
-      case 288: /* key_opt ::= */
-{ yygotominor.yy172 = 0; }
-        break;
-      case 272: /* when_clause ::= WHEN expr */
-      case 289: /* key_opt ::= KEY expr */
-{ yygotominor.yy172 = yymsp[0].minor.yy172; }
-        break;
-      case 273: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
-{
-  if( yymsp[-2].minor.yy243 ){
-    yymsp[-2].minor.yy243->pLast->pNext = yymsp[-1].minor.yy243;
+
+/*
+** Invoke the xFileControl method on a particular database.
+*/
+SQLITE_API int sqlite3_file_control(sqlite3 *db, const char *zDbName, int op, void *pArg){
+  int rc = SQLITE_ERROR;
+  int iDb;
+  sqlite3_mutex_enter(db->mutex);
+  if( zDbName==0 ){
+    iDb = 0;
   }else{
-    yymsp[-2].minor.yy243 = yymsp[-1].minor.yy243;
+    for(iDb=0; iDb<db->nDb; iDb++){
+      if( strcmp(db->aDb[iDb].zName, zDbName)==0 ) break;
+    }
   }
-  yymsp[-2].minor.yy243->pLast = yymsp[-1].minor.yy243;
-  yygotominor.yy243 = yymsp[-2].minor.yy243;
-}
-        break;
-      case 274: /* trigger_cmd_list ::= */
-{ yygotominor.yy243 = 0; }
-        break;
-      case 275: /* trigger_cmd ::= UPDATE orconf nm SET setlist where_opt */
-{ yygotominor.yy243 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-3].minor.yy410, yymsp[-1].minor.yy174, yymsp[0].minor.yy172, yymsp[-4].minor.yy46); }
-        break;
-      case 276: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP */
-{yygotominor.yy243 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy410, yymsp[-4].minor.yy432, yymsp[-1].minor.yy174, 0, yymsp[-7].minor.yy46);}
-        break;
-      case 277: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt select */
-{yygotominor.yy243 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy410, yymsp[-1].minor.yy432, 0, yymsp[0].minor.yy219, yymsp[-4].minor.yy46);}
-        break;
-      case 278: /* trigger_cmd ::= DELETE FROM nm where_opt */
-{yygotominor.yy243 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-1].minor.yy410, yymsp[0].minor.yy172);}
-        break;
-      case 279: /* trigger_cmd ::= select */
-{yygotominor.yy243 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy219); }
-        break;
-      case 280: /* expr ::= RAISE LP IGNORE RP */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->iColumn = OE_Ignore;
-    sqlite3ExprSpan(yygotominor.yy172, &yymsp[-3].minor.yy0, &yymsp[0].minor.yy0);
+  if( iDb<db->nDb ){
+    Btree *pBtree = db->aDb[iDb].pBt;
+    if( pBtree ){
+      Pager *pPager;
+      sqlite3_file *fd;
+      sqlite3BtreeEnter(pBtree);
+      pPager = sqlite3BtreePager(pBtree);
+      assert( pPager!=0 );
+      fd = sqlite3PagerFile(pPager);
+      assert( fd!=0 );
+      if( fd->pMethods ){
+        rc = sqlite3OsFileControl(fd, op, pArg);
+      }
+      sqlite3BtreeLeave(pBtree);
+    }
   }
+  sqlite3_mutex_leave(db->mutex);
+  return rc;   
 }
-        break;
-      case 281: /* expr ::= RAISE LP raisetype COMMA nm RP */
-{
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy410); 
-  if( yygotominor.yy172 ) {
-    yygotominor.yy172->iColumn = yymsp[-3].minor.yy46;
-    sqlite3ExprSpan(yygotominor.yy172, &yymsp[-5].minor.yy0, &yymsp[0].minor.yy0);
+
+/*
+** Interface to the testing logic.
+*/
+SQLITE_API int sqlite3_test_control(int op, ...){
+  int rc = 0;
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+  va_list ap;
+  va_start(ap, op);
+  switch( op ){
+
+    /*
+    ** Save the current state of the PRNG.
+    */
+    case SQLITE_TESTCTRL_PRNG_SAVE: {
+      sqlite3PrngSaveState();
+      break;
+    }
+
+    /*
+    ** Restore the state of the PRNG to the last state saved using
+    ** PRNG_SAVE.  If PRNG_SAVE has never before been called, then
+    ** this verb acts like PRNG_RESET.
+    */
+    case SQLITE_TESTCTRL_PRNG_RESTORE: {
+      sqlite3PrngRestoreState();
+      break;
+    }
+
+    /*
+    ** Reset the PRNG back to its uninitialized state.  The next call
+    ** to sqlite3_randomness() will reseed the PRNG using a single call
+    ** to the xRandomness method of the default VFS.
+    */
+    case SQLITE_TESTCTRL_PRNG_RESET: {
+      sqlite3PrngResetState();
+      break;
+    }
+
+    /*
+    **  sqlite3_test_control(BITVEC_TEST, size, program)
+    **
+    ** Run a test against a Bitvec object of size.  The program argument
+    ** is an array of integers that defines the test.  Return -1 on a
+    ** memory allocation error, 0 on success, or non-zero for an error.
+    ** See the sqlite3BitvecBuiltinTest() for additional information.
+    */
+    case SQLITE_TESTCTRL_BITVEC_TEST: {
+      int sz = va_arg(ap, int);
+      int *aProg = va_arg(ap, int*);
+      rc = sqlite3BitvecBuiltinTest(sz, aProg);
+      break;
+    }
+
+    /*
+    **  sqlite3_test_control(BENIGN_MALLOC_HOOKS, xBegin, xEnd)
+    **
+    ** Register hooks to call to indicate which malloc() failures 
+    ** are benign.
+    */
+    case SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS: {
+      typedef void (*void_function)(void);
+      void_function xBenignBegin;
+      void_function xBenignEnd;
+      xBenignBegin = va_arg(ap, void_function);
+      xBenignEnd = va_arg(ap, void_function);
+      sqlite3BenignMallocHooks(xBenignBegin, xBenignEnd);
+      break;
+    }
+
+    /*
+    **  sqlite3_test_control(SQLITE_TESTCTRL_PENDING_BYTE, unsigned int X)
+    **
+    ** Set the PENDING byte to the value in the argument, if X>0.
+    ** Make no changes if X==0.  Return the value of the pending byte
+    ** as it existing before this routine was called.
+    **
+    ** IMPORTANT:  Changing the PENDING byte from 0x40000000 results in
+    ** an incompatible database file format.  Changing the PENDING byte
+    ** while any database connection is open results in undefined and
+    ** dileterious behavior.
+    */
+    case SQLITE_TESTCTRL_PENDING_BYTE: {
+      unsigned int newVal = va_arg(ap, unsigned int);
+      rc = sqlite3PendingByte;
+      if( newVal ) sqlite3PendingByte = newVal;
+      break;
+    }
+
+    /*
+    **  sqlite3_test_control(SQLITE_TESTCTRL_ASSERT, int X)
+    **
+    ** This action provides a run-time test to see whether or not
+    ** assert() was enabled at compile-time.  If X is true and assert()
+    ** is enabled, then the return value is true.  If X is true and
+    ** assert() is disabled, then the return value is zero.  If X is
+    ** false and assert() is enabled, then the assertion fires and the
+    ** process aborts.  If X is false and assert() is disabled, then the
+    ** return value is zero.
+    */
+    case SQLITE_TESTCTRL_ASSERT: {
+      volatile int x = 0;
+      assert( (x = va_arg(ap,int))!=0 );
+      rc = x;
+      break;
+    }
+
+
+    /*
+    **  sqlite3_test_control(SQLITE_TESTCTRL_ALWAYS, int X)
+    **
+    ** This action provides a run-time test to see how the ALWAYS and
+    ** NEVER macros were defined at compile-time.
+    **
+    ** The return value is ALWAYS(X).  
+    **
+    ** The recommended test is X==2.  If the return value is 2, that means
+    ** ALWAYS() and NEVER() are both no-op pass-through macros, which is the
+    ** default setting.  If the return value is 1, then ALWAYS() is either
+    ** hard-coded to true or else it asserts if its argument is false.
+    ** The first behavior (hard-coded to true) is the case if
+    ** SQLITE_TESTCTRL_ASSERT shows that assert() is disabled and the second
+    ** behavior (assert if the argument to ALWAYS() is false) is the case if
+    ** SQLITE_TESTCTRL_ASSERT shows that assert() is enabled.
+    **
+    ** The run-time test procedure might look something like this:
+    **
+    **    if( sqlite3_test_control(SQLITE_TESTCTRL_ALWAYS, 2)==2 ){
+    **      // ALWAYS() and NEVER() are no-op pass-through macros
+    **    }else if( sqlite3_test_control(SQLITE_TESTCTRL_ASSERT, 1) ){
+    **      // ALWAYS(x) asserts that x is true. NEVER(x) asserts x is false.
+    **    }else{
+    **      // ALWAYS(x) is a constant 1.  NEVER(x) is a constant 0.
+    **    }
+    */
+    case SQLITE_TESTCTRL_ALWAYS: {
+      int x = va_arg(ap,int);
+      rc = ALWAYS(x);
+      break;
+    }
+
+    /*   sqlite3_test_control(SQLITE_TESTCTRL_RESERVE, sqlite3 *db, int N)
+    **
+    ** Set the nReserve size to N for the main database on the database
+    ** connection db.
+    */
+    case SQLITE_TESTCTRL_RESERVE: {
+      sqlite3 *db = va_arg(ap, sqlite3*);
+      int x = va_arg(ap,int);
+      sqlite3_mutex_enter(db->mutex);
+      sqlite3BtreeSetPageSize(db->aDb[0].pBt, 0, x, 0);
+      sqlite3_mutex_leave(db->mutex);
+      break;
+    }
+
   }
+  va_end(ap);
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
+  return rc;
 }
-        break;
-      case 282: /* raisetype ::= ROLLBACK */
-{yygotominor.yy46 = OE_Rollback;}
-        break;
-      case 284: /* raisetype ::= FAIL */
-{yygotominor.yy46 = OE_Fail;}
-        break;
-      case 285: /* cmd ::= DROP TRIGGER ifexists fullname */
-{
-  sqlite3DropTrigger(pParse,yymsp[0].minor.yy373,yymsp[-1].minor.yy46);
-}
-        break;
-      case 286: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
-{
-  sqlite3Attach(pParse, yymsp[-3].minor.yy172, yymsp[-1].minor.yy172, yymsp[0].minor.yy172);
-}
-        break;
-      case 287: /* cmd ::= DETACH database_kw_opt expr */
-{
-  sqlite3Detach(pParse, yymsp[0].minor.yy172);
-}
-        break;
-      case 292: /* cmd ::= REINDEX */
-{sqlite3Reindex(pParse, 0, 0);}
-        break;
-      case 293: /* cmd ::= REINDEX nm dbnm */
-{sqlite3Reindex(pParse, &yymsp[-1].minor.yy410, &yymsp[0].minor.yy410);}
-        break;
-      case 294: /* cmd ::= ANALYZE */
-{sqlite3Analyze(pParse, 0, 0);}
-        break;
-      case 295: /* cmd ::= ANALYZE nm dbnm */
-{sqlite3Analyze(pParse, &yymsp[-1].minor.yy410, &yymsp[0].minor.yy410);}
-        break;
-      case 296: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
-{
-  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy373,&yymsp[0].minor.yy410);
-}
-        break;
-      case 297: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
-{
-  sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy410);
-}
-        break;
-      case 298: /* add_column_fullname ::= fullname */
-{
-  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy373);
-}
-        break;
-      case 301: /* cmd ::= create_vtab */
-{sqlite3VtabFinishParse(pParse,0);}
-        break;
-      case 302: /* cmd ::= create_vtab LP vtabarglist RP */
-{sqlite3VtabFinishParse(pParse,&yymsp[0].minor.yy0);}
-        break;
-      case 303: /* create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm */
-{
-    sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy410, &yymsp[-2].minor.yy410, &yymsp[0].minor.yy410);
+
+/************** End of main.c ************************************************/
+/************** Begin file notify.c ******************************************/
+/*
+** 2009 March 3
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains the implementation of the sqlite3_unlock_notify()
+** API method and its associated functionality.
+**
+** $Id: notify.c,v 1.4 2009/04/07 22:06:57 drh Exp $
+*/
+
+/* Omit this entire file if SQLITE_ENABLE_UNLOCK_NOTIFY is not defined. */
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+
+/*
+** Public interfaces:
+**
+**   sqlite3ConnectionBlocked()
+**   sqlite3ConnectionUnlocked()
+**   sqlite3ConnectionClosed()
+**   sqlite3_unlock_notify()
+*/
+
+#define assertMutexHeld() \
+  assert( sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)) )
+
+/*
+** Head of a linked list of all sqlite3 objects created by this process
+** for which either sqlite3.pBlockingConnection or sqlite3.pUnlockConnection
+** is not NULL. This variable may only accessed while the STATIC_MASTER
+** mutex is held.
+*/
+static sqlite3 *SQLITE_WSD sqlite3BlockedList = 0;
+
+#ifndef NDEBUG
+/*
+** This function is a complex assert() that verifies the following 
+** properties of the blocked connections list:
+**
+**   1) Each entry in the list has a non-NULL value for either 
+**      pUnlockConnection or pBlockingConnection, or both.
+**
+**   2) All entries in the list that share a common value for 
+**      xUnlockNotify are grouped together.
+**
+**   3) If the argument db is not NULL, then none of the entries in the
+**      blocked connections list have pUnlockConnection or pBlockingConnection
+**      set to db. This is used when closing connection db.
+*/
+static void checkListProperties(sqlite3 *db){
+  sqlite3 *p;
+  for(p=sqlite3BlockedList; p; p=p->pNextBlocked){
+    int seen = 0;
+    sqlite3 *p2;
+
+    /* Verify property (1) */
+    assert( p->pUnlockConnection || p->pBlockingConnection );
+
+    /* Verify property (2) */
+    for(p2=sqlite3BlockedList; p2!=p; p2=p2->pNextBlocked){
+      if( p2->xUnlockNotify==p->xUnlockNotify ) seen = 1;
+      assert( p2->xUnlockNotify==p->xUnlockNotify || !seen );
+      assert( db==0 || p->pUnlockConnection!=db );
+      assert( db==0 || p->pBlockingConnection!=db );
+    }
+  }
 }
-        break;
-      case 306: /* vtabarg ::= */
-{sqlite3VtabArgInit(pParse);}
-        break;
-      case 308: /* vtabargtoken ::= ANY */
-      case 309: /* vtabargtoken ::= lp anylist RP */
-      case 310: /* lp ::= LP */
-      case 312: /* anylist ::= anylist ANY */
-{sqlite3VtabArgExtend(pParse,&yymsp[0].minor.yy0);}
-        break;
-  };
-  yygoto = yyRuleInfo[yyruleno].lhs;
-  yysize = yyRuleInfo[yyruleno].nrhs;
-  yypParser->yyidx -= yysize;
-  yyact = yy_find_reduce_action(yymsp[-yysize].stateno,yygoto);
-  if( yyact < YYNSTATE ){
-#ifdef NDEBUG
-    /* If we are not debugging and the reduce action popped at least
-    ** one element off the stack, then we can push the new element back
-    ** onto the stack here, and skip the stack overflow test in yy_shift().
-    ** That gives a significant speed improvement. */
-    if( yysize ){
-      yypParser->yyidx++;
-      yymsp -= yysize-1;
-      yymsp->stateno = yyact;
-      yymsp->major = yygoto;
-      yymsp->minor = yygotominor;
-    }else
+#else
+# define checkListProperties(x)
 #endif
-    {
-      yy_shift(yypParser,yyact,yygoto,&yygotominor);
+
+/*
+** Remove connection db from the blocked connections list. If connection
+** db is not currently a part of the list, this function is a no-op.
+*/
+static void removeFromBlockedList(sqlite3 *db){
+  sqlite3 **pp;
+  assertMutexHeld();
+  for(pp=&sqlite3BlockedList; *pp; pp = &(*pp)->pNextBlocked){
+    if( *pp==db ){
+      *pp = (*pp)->pNextBlocked;
+      break;
     }
-  }else{
-    assert( yyact == YYNSTATE + YYNRULE + 1 );
-    yy_accept(yypParser);
   }
 }
 
 /*
-** The following code executes when the parse fails
+** Add connection db to the blocked connections list. It is assumed
+** that it is not already a part of the list.
 */
-static void yy_parse_failed(
-  yyParser *yypParser           /* The parser */
-){
-  sqlite3ParserARG_FETCH;
-#ifndef NDEBUG
-  if( yyTraceFILE ){
-    fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt);
-  }
-#endif
-  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
-  /* Here code is inserted which will be executed whenever the
-  ** parser fails */
-  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
+static void addToBlockedList(sqlite3 *db){
+  sqlite3 **pp;
+  assertMutexHeld();
+  for(
+    pp=&sqlite3BlockedList; 
+    *pp && (*pp)->xUnlockNotify!=db->xUnlockNotify; 
+    pp=&(*pp)->pNextBlocked
+  );
+  db->pNextBlocked = *pp;
+  *pp = db;
 }
 
 /*
-** The following code executes when a syntax error first occurs.
+** Obtain the STATIC_MASTER mutex.
 */
-static void yy_syntax_error(
-  yyParser *yypParser,           /* The parser */
-  int yymajor,                   /* The major type of the error token */
-  YYMINORTYPE yyminor            /* The minor type of the error token */
-){
-  sqlite3ParserARG_FETCH;
-#define TOKEN (yyminor.yy0)
-
-  assert( TOKEN.z[0] );  /* The tokenizer always gives us a token */
-  sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &TOKEN);
-  pParse->parseError = 1;
-  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
+static void enterMutex(void){
+  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+  checkListProperties(0);
 }
 
 /*
-** The following is executed when the parser accepts
+** Release the STATIC_MASTER mutex.
 */
-static void yy_accept(
-  yyParser *yypParser           /* The parser */
-){
-  sqlite3ParserARG_FETCH;
-#ifndef NDEBUG
-  if( yyTraceFILE ){
-    fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt);
-  }
-#endif
-  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
-  /* Here code is inserted which will be executed whenever the
-  ** parser accepts */
-  sqlite3ParserARG_STORE; /* Suppress warning about unused %extra_argument variable */
+static void leaveMutex(void){
+  assertMutexHeld();
+  checkListProperties(0);
+  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
 }
 
-/* The main parser program.
-** The first argument is a pointer to a structure obtained from
-** "sqlite3ParserAlloc" which describes the current state of the parser.
-** The second argument is the major token number.  The third is
-** the minor token.  The fourth optional argument is whatever the
-** user wants (and specified in the grammar) and is available for
-** use by the action routines.
+/*
+** Register an unlock-notify callback.
 **
-** Inputs:
-** <ul>
-** <li> A pointer to the parser (an opaque structure.)
-** <li> The major token number.
-** <li> The minor token number.
-** <li> An option argument of a grammar-specified type.
-** </ul>
+** This is called after connection "db" has attempted some operation
+** but has received an SQLITE_LOCKED error because another connection
+** (call it pOther) in the same process was busy using the same shared
+** cache.  pOther is found by looking at db->pBlockingConnection.
 **
-** Outputs:
-** None.
+** If there is no blocking connection, the callback is invoked immediately,
+** before this routine returns.
+**
+** If pOther is already blocked on db, then report SQLITE_LOCKED, to indicate
+** a deadlock.
+**
+** Otherwise, make arrangements to invoke xNotify when pOther drops
+** its locks.
+**
+** Each call to this routine overrides any prior callbacks registered
+** on the same "db".  If xNotify==0 then any prior callbacks are immediately
+** cancelled.
 */
-SQLITE_PRIVATE void sqlite3Parser(
-  void *yyp,                   /* The parser */
-  int yymajor,                 /* The major token code number */
-  sqlite3ParserTOKENTYPE yyminor       /* The value for the token */
-  sqlite3ParserARG_PDECL               /* Optional %extra_argument parameter */
+SQLITE_API int sqlite3_unlock_notify(
+  sqlite3 *db,
+  void (*xNotify)(void **, int),
+  void *pArg
 ){
-  YYMINORTYPE yyminorunion;
-  int yyact;            /* The parser action. */
-  int yyendofinput;     /* True if we are at the end of input */
-#ifdef YYERRORSYMBOL
-  int yyerrorhit = 0;   /* True if yymajor has invoked an error */
-#endif
-  yyParser *yypParser;  /* The parser */
+  int rc = SQLITE_OK;
 
-  /* (re)initialize the parser, if necessary */
-  yypParser = (yyParser*)yyp;
-  if( yypParser->yyidx<0 ){
-#if YYSTACKDEPTH<=0
-    if( yypParser->yystksz <=0 ){
-      /*memset(&yyminorunion, 0, sizeof(yyminorunion));*/
-      yyminorunion = yyzerominor;
-      yyStackOverflow(yypParser, &yyminorunion);
-      return;
+  sqlite3_mutex_enter(db->mutex);
+  enterMutex();
+
+  if( xNotify==0 ){
+    removeFromBlockedList(db);
+    db->pUnlockConnection = 0;
+    db->xUnlockNotify = 0;
+    db->pUnlockArg = 0;
+  }else if( 0==db->pBlockingConnection ){
+    /* The blocking transaction has been concluded. Or there never was a 
+    ** blocking transaction. In either case, invoke the notify callback
+    ** immediately. 
+    */
+    xNotify(&pArg, 1);
+  }else{
+    sqlite3 *p;
+
+    for(p=db->pBlockingConnection; p && p!=db; p=p->pUnlockConnection){}
+    if( p ){
+      rc = SQLITE_LOCKED;              /* Deadlock detected. */
+    }else{
+      db->pUnlockConnection = db->pBlockingConnection;
+      db->xUnlockNotify = xNotify;
+      db->pUnlockArg = pArg;
+      removeFromBlockedList(db);
+      addToBlockedList(db);
     }
-#endif
-    yypParser->yyidx = 0;
-    yypParser->yyerrcnt = -1;
-    yypParser->yystack[0].stateno = 0;
-    yypParser->yystack[0].major = 0;
   }
-  yyminorunion.yy0 = yyminor;
-  yyendofinput = (yymajor==0);
-  sqlite3ParserARG_STORE;
 
-#ifndef NDEBUG
-  if( yyTraceFILE ){
-    fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]);
+  leaveMutex();
+  assert( !db->mallocFailed );
+  sqlite3Error(db, rc, (rc?"database is deadlocked":0));
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/*
+** This function is called while stepping or preparing a statement 
+** associated with connection db. The operation will return SQLITE_LOCKED
+** to the user because it requires a lock that will not be available
+** until connection pBlocker concludes its current transaction.
+*/
+SQLITE_PRIVATE void sqlite3ConnectionBlocked(sqlite3 *db, sqlite3 *pBlocker){
+  enterMutex();
+  if( db->pBlockingConnection==0 && db->pUnlockConnection==0 ){
+    addToBlockedList(db);
   }
-#endif
+  db->pBlockingConnection = pBlocker;
+  leaveMutex();
+}
 
-  do{
-    yyact = yy_find_shift_action(yypParser,yymajor);
-    if( yyact<YYNSTATE ){
-      assert( !yyendofinput );  /* Impossible to shift the $ token */
-      yy_shift(yypParser,yyact,yymajor,&yyminorunion);
-      yypParser->yyerrcnt--;
-      yymajor = YYNOCODE;
-    }else if( yyact < YYNSTATE + YYNRULE ){
-      yy_reduce(yypParser,yyact-YYNSTATE);
-    }else{
-      assert( yyact == YY_ERROR_ACTION );
-#ifdef YYERRORSYMBOL
-      int yymx;
-#endif
-#ifndef NDEBUG
-      if( yyTraceFILE ){
-        fprintf(yyTraceFILE,"%sSyntax Error!\n",yyTracePrompt);
-      }
-#endif
-#ifdef YYERRORSYMBOL
-      /* A syntax error has occurred.
-      ** The response to an error depends upon whether or not the
-      ** grammar defines an error token "ERROR".  
-      **
-      ** This is what we do if the grammar does define ERROR:
-      **
-      **  * Call the %syntax_error function.
-      **
-      **  * Begin popping the stack until we enter a state where
-      **    it is legal to shift the error symbol, then shift
-      **    the error symbol.
-      **
-      **  * Set the error count to three.
-      **
-      **  * Begin accepting and shifting new tokens.  No new error
-      **    processing will occur until three tokens have been
-      **    shifted successfully.
-      **
-      */
-      if( yypParser->yyerrcnt<0 ){
-        yy_syntax_error(yypParser,yymajor,yyminorunion);
+/*
+** This function is called when
+** the transaction opened by database db has just finished. Locks held 
+** by database connection db have been released.
+**
+** This function loops through each entry in the blocked connections
+** list and does the following:
+**
+**   1) If the sqlite3.pBlockingConnection member of a list entry is
+**      set to db, then set pBlockingConnection=0.
+**
+**   2) If the sqlite3.pUnlockConnection member of a list entry is
+**      set to db, then invoke the configured unlock-notify callback and
+**      set pUnlockConnection=0.
+**
+**   3) If the two steps above mean that pBlockingConnection==0 and
+**      pUnlockConnection==0, remove the entry from the blocked connections
+**      list.
+*/
+SQLITE_PRIVATE void sqlite3ConnectionUnlocked(sqlite3 *db){
+  void (*xUnlockNotify)(void **, int) = 0; /* Unlock-notify cb to invoke */
+  int nArg = 0;                            /* Number of entries in aArg[] */
+  sqlite3 **pp;                            /* Iterator variable */
+  void **aArg;               /* Arguments to the unlock callback */
+  void **aDyn = 0;           /* Dynamically allocated space for aArg[] */
+  void *aStatic[16];         /* Starter space for aArg[].  No malloc required */
+
+  aArg = aStatic;
+  enterMutex();         /* Enter STATIC_MASTER mutex */
+
+  /* This loop runs once for each entry in the blocked-connections list. */
+  for(pp=&sqlite3BlockedList; *pp; /* no-op */ ){
+    sqlite3 *p = *pp;
+
+    /* Step 1. */
+    if( p->pBlockingConnection==db ){
+      p->pBlockingConnection = 0;
+    }
+
+    /* Step 2. */
+    if( p->pUnlockConnection==db ){
+      assert( p->xUnlockNotify );
+      if( p->xUnlockNotify!=xUnlockNotify && nArg!=0 ){
+        xUnlockNotify(aArg, nArg);
+        nArg = 0;
       }
-      yymx = yypParser->yystack[yypParser->yyidx].major;
-      if( yymx==YYERRORSYMBOL || yyerrorhit ){
-#ifndef NDEBUG
-        if( yyTraceFILE ){
-          fprintf(yyTraceFILE,"%sDiscard input token %s\n",
-             yyTracePrompt,yyTokenName[yymajor]);
-        }
-#endif
-        yy_destructor(yymajor,&yyminorunion);
-        yymajor = YYNOCODE;
-      }else{
-         while(
-          yypParser->yyidx >= 0 &&
-          yymx != YYERRORSYMBOL &&
-          (yyact = yy_find_reduce_action(
-                        yypParser->yystack[yypParser->yyidx].stateno,
-                        YYERRORSYMBOL)) >= YYNSTATE
-        ){
-          yy_pop_parser_stack(yypParser);
-        }
-        if( yypParser->yyidx < 0 || yymajor==0 ){
-          yy_destructor(yymajor,&yyminorunion);
-          yy_parse_failed(yypParser);
-          yymajor = YYNOCODE;
-        }else if( yymx!=YYERRORSYMBOL ){
-          YYMINORTYPE u2;
-          u2.YYERRSYMDT = 0;
-          yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2);
+
+      sqlite3BeginBenignMalloc();
+      assert( aArg==aDyn || (aDyn==0 && aArg==aStatic) );
+      assert( nArg<=(int)ArraySize(aStatic) || aArg==aDyn );
+      if( (!aDyn && nArg==(int)ArraySize(aStatic))
+       || (aDyn && nArg==(int)(sqlite3DbMallocSize(db, aDyn)/sizeof(void*)))
+      ){
+        /* The aArg[] array needs to grow. */
+        void **pNew = (void **)sqlite3Malloc(nArg*sizeof(void *)*2);
+        if( pNew ){
+          memcpy(pNew, aArg, nArg*sizeof(void *));
+          sqlite3_free(aDyn);
+          aDyn = aArg = pNew;
+        }else{
+          /* This occurs when the array of context pointers that need to
+          ** be passed to the unlock-notify callback is larger than the
+          ** aStatic[] array allocated on the stack and the attempt to 
+          ** allocate a larger array from the heap has failed.
+          **
+          ** This is a difficult situation to handle. Returning an error
+          ** code to the caller is insufficient, as even if an error code
+          ** is returned the transaction on connection db will still be
+          ** closed and the unlock-notify callbacks on blocked connections
+          ** will go unissued. This might cause the application to wait
+          ** indefinitely for an unlock-notify callback that will never 
+          ** arrive.
+          **
+          ** Instead, invoke the unlock-notify callback with the context
+          ** array already accumulated. We can then clear the array and
+          ** begin accumulating any further context pointers without 
+          ** requiring any dynamic allocation. This is sub-optimal because
+          ** it means that instead of one callback with a large array of
+          ** context pointers the application will receive two or more
+          ** callbacks with smaller arrays of context pointers, which will
+          ** reduce the applications ability to prioritize multiple 
+          ** connections. But it is the best that can be done under the
+          ** circumstances.
+          */
+          xUnlockNotify(aArg, nArg);
+          nArg = 0;
         }
       }
-      yypParser->yyerrcnt = 3;
-      yyerrorhit = 1;
-#else  /* YYERRORSYMBOL is not defined */
-      /* This is what we do if the grammar does not define ERROR:
-      **
-      **  * Report an error message, and throw away the input token.
-      **
-      **  * If the input token is $, then fail the parse.
-      **
-      ** As before, subsequent error messages are suppressed until
-      ** three input tokens have been successfully shifted.
-      */
-      if( yypParser->yyerrcnt<=0 ){
-        yy_syntax_error(yypParser,yymajor,yyminorunion);
-      }
-      yypParser->yyerrcnt = 3;
-      yy_destructor(yymajor,&yyminorunion);
-      if( yyendofinput ){
-        yy_parse_failed(yypParser);
-      }
-      yymajor = YYNOCODE;
-#endif
+      sqlite3EndBenignMalloc();
+
+      aArg[nArg++] = p->pUnlockArg;
+      xUnlockNotify = p->xUnlockNotify;
+      p->pUnlockConnection = 0;
+      p->xUnlockNotify = 0;
+      p->pUnlockArg = 0;
     }
-  }while( yymajor!=YYNOCODE && yypParser->yyidx>=0 );
-  return;
+
+    /* Step 3. */
+    if( p->pBlockingConnection==0 && p->pUnlockConnection==0 ){
+      /* Remove connection p from the blocked connections list. */
+      *pp = p->pNextBlocked;
+      p->pNextBlocked = 0;
+    }else{
+      pp = &p->pNextBlocked;
+    }
+  }
+
+  if( nArg!=0 ){
+    xUnlockNotify(aArg, nArg);
+  }
+  sqlite3_free(aDyn);
+  leaveMutex();         /* Leave STATIC_MASTER mutex */
 }
 
-/************** End of parse.c ***********************************************/
-/************** Begin file tokenize.c ****************************************/
 /*
-** 2001 September 15
+** This is called when the database connection passed as an argument is 
+** being closed. The connection is removed from the blocked list.
+*/
+SQLITE_PRIVATE void sqlite3ConnectionClosed(sqlite3 *db){
+  sqlite3ConnectionUnlocked(db);
+  enterMutex();
+  removeFromBlockedList(db);
+  checkListProperties(db);
+  leaveMutex();
+}
+#endif
+
+/************** End of notify.c **********************************************/
+/************** Begin file fts3.c ********************************************/
+/*
+** 2006 Oct 10
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -76173,10275 +97113,12746 @@ SQLITE_PRIVATE void sqlite3Parser(
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-*************************************************************************
-** An tokenizer for SQL
-**
-** This file contains C code that splits an SQL input string up into
-** individual tokens and sends those tokens one-by-one over to the
-** parser for analysis.
+******************************************************************************
 **
-** $Id: tokenize.c,v 1.142 2008/04/28 18:46:43 drh Exp $
+** This is an SQLite module implementing full-text search.
 */
 
 /*
-** The charMap() macro maps alphabetic characters into their
-** lower-case ASCII equivalent.  On ASCII machines, this is just
-** an upper-to-lower case map.  On EBCDIC machines we also need
-** to adjust the encoding.  Only alphabetic characters and underscores
-** need to be translated.
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
 */
-#ifdef SQLITE_ASCII
-# define charMap(X) sqlite3UpperToLower[(unsigned char)X]
-#endif
-#ifdef SQLITE_EBCDIC
-# define charMap(X) ebcdicToAscii[(unsigned char)X]
-const unsigned char ebcdicToAscii[] = {
-/* 0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 0x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 1x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 2x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 3x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 4x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 5x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 95,  0,  0,  /* 6x */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* 7x */
-   0, 97, 98, 99,100,101,102,103,104,105,  0,  0,  0,  0,  0,  0,  /* 8x */
-   0,106,107,108,109,110,111,112,113,114,  0,  0,  0,  0,  0,  0,  /* 9x */
-   0,  0,115,116,117,118,119,120,121,122,  0,  0,  0,  0,  0,  0,  /* Ax */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* Bx */
-   0, 97, 98, 99,100,101,102,103,104,105,  0,  0,  0,  0,  0,  0,  /* Cx */
-   0,106,107,108,109,110,111,112,113,114,  0,  0,  0,  0,  0,  0,  /* Dx */
-   0,  0,115,116,117,118,119,120,121,122,  0,  0,  0,  0,  0,  0,  /* Ex */
-   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  /* Fx */
-};
+
+/* TODO(shess) Consider exporting this comment to an HTML file or the
+** wiki.
+*/
+/* The full-text index is stored in a series of b+tree (-like)
+** structures called segments which map terms to doclists.  The
+** structures are like b+trees in layout, but are constructed from the
+** bottom up in optimal fashion and are not updatable.  Since trees
+** are built from the bottom up, things will be described from the
+** bottom up.
+**
+**
+**** Varints ****
+** The basic unit of encoding is a variable-length integer called a
+** varint.  We encode variable-length integers in little-endian order
+** using seven bits * per byte as follows:
+**
+** KEY:
+**         A = 0xxxxxxx    7 bits of data and one flag bit
+**         B = 1xxxxxxx    7 bits of data and one flag bit
+**
+**  7 bits - A
+** 14 bits - BA
+** 21 bits - BBA
+** and so on.
+**
+** This is identical to how sqlite encodes varints (see util.c).
+**
+**
+**** Document lists ****
+** A doclist (document list) holds a docid-sorted list of hits for a
+** given term.  Doclists hold docids, and can optionally associate
+** token positions and offsets with docids.
+**
+** A DL_POSITIONS_OFFSETS doclist is stored like this:
+**
+** array {
+**   varint docid;
+**   array {                (position list for column 0)
+**     varint position;     (delta from previous position plus POS_BASE)
+**     varint startOffset;  (delta from previous startOffset)
+**     varint endOffset;    (delta from startOffset)
+**   }
+**   array {
+**     varint POS_COLUMN;   (marks start of position list for new column)
+**     varint column;       (index of new column)
+**     array {
+**       varint position;   (delta from previous position plus POS_BASE)
+**       varint startOffset;(delta from previous startOffset)
+**       varint endOffset;  (delta from startOffset)
+**     }
+**   }
+**   varint POS_END;        (marks end of positions for this document.
+** }
+**
+** Here, array { X } means zero or more occurrences of X, adjacent in
+** memory.  A "position" is an index of a token in the token stream
+** generated by the tokenizer, while an "offset" is a byte offset,
+** both based at 0.  Note that POS_END and POS_COLUMN occur in the
+** same logical place as the position element, and act as sentinals
+** ending a position list array.
+**
+** A DL_POSITIONS doclist omits the startOffset and endOffset
+** information.  A DL_DOCIDS doclist omits both the position and
+** offset information, becoming an array of varint-encoded docids.
+**
+** On-disk data is stored as type DL_DEFAULT, so we don't serialize
+** the type.  Due to how deletion is implemented in the segmentation
+** system, on-disk doclists MUST store at least positions.
+**
+**
+**** Segment leaf nodes ****
+** Segment leaf nodes store terms and doclists, ordered by term.  Leaf
+** nodes are written using LeafWriter, and read using LeafReader (to
+** iterate through a single leaf node's data) and LeavesReader (to
+** iterate through a segment's entire leaf layer).  Leaf nodes have
+** the format:
+**
+** varint iHeight;             (height from leaf level, always 0)
+** varint nTerm;               (length of first term)
+** char pTerm[nTerm];          (content of first term)
+** varint nDoclist;            (length of term's associated doclist)
+** char pDoclist[nDoclist];    (content of doclist)
+** array {
+**                             (further terms are delta-encoded)
+**   varint nPrefix;           (length of prefix shared with previous term)
+**   varint nSuffix;           (length of unshared suffix)
+**   char pTermSuffix[nSuffix];(unshared suffix of next term)
+**   varint nDoclist;          (length of term's associated doclist)
+**   char pDoclist[nDoclist];  (content of doclist)
+** }
+**
+** Here, array { X } means zero or more occurrences of X, adjacent in
+** memory.
+**
+** Leaf nodes are broken into blocks which are stored contiguously in
+** the %_segments table in sorted order.  This means that when the end
+** of a node is reached, the next term is in the node with the next
+** greater node id.
+**
+** New data is spilled to a new leaf node when the current node
+** exceeds LEAF_MAX bytes (default 2048).  New data which itself is
+** larger than STANDALONE_MIN (default 1024) is placed in a standalone
+** node (a leaf node with a single term and doclist).  The goal of
+** these settings is to pack together groups of small doclists while
+** making it efficient to directly access large doclists.  The
+** assumption is that large doclists represent terms which are more
+** likely to be query targets.
+**
+** TODO(shess) It may be useful for blocking decisions to be more
+** dynamic.  For instance, it may make more sense to have a 2.5k leaf
+** node rather than splitting into 2k and .5k nodes.  My intuition is
+** that this might extend through 2x or 4x the pagesize.
+**
+**
+**** Segment interior nodes ****
+** Segment interior nodes store blockids for subtree nodes and terms
+** to describe what data is stored by the each subtree.  Interior
+** nodes are written using InteriorWriter, and read using
+** InteriorReader.  InteriorWriters are created as needed when
+** SegmentWriter creates new leaf nodes, or when an interior node
+** itself grows too big and must be split.  The format of interior
+** nodes:
+**
+** varint iHeight;           (height from leaf level, always >0)
+** varint iBlockid;          (block id of node's leftmost subtree)
+** optional {
+**   varint nTerm;           (length of first term)
+**   char pTerm[nTerm];      (content of first term)
+**   array {
+**                                (further terms are delta-encoded)
+**     varint nPrefix;            (length of shared prefix with previous term)
+**     varint nSuffix;            (length of unshared suffix)
+**     char pTermSuffix[nSuffix]; (unshared suffix of next term)
+**   }
+** }
+**
+** Here, optional { X } means an optional element, while array { X }
+** means zero or more occurrences of X, adjacent in memory.
+**
+** An interior node encodes n terms separating n+1 subtrees.  The
+** subtree blocks are contiguous, so only the first subtree's blockid
+** is encoded.  The subtree at iBlockid will contain all terms less
+** than the first term encoded (or all terms if no term is encoded).
+** Otherwise, for terms greater than or equal to pTerm[i] but less
+** than pTerm[i+1], the subtree for that term will be rooted at
+** iBlockid+i.  Interior nodes only store enough term data to
+** distinguish adjacent children (if the rightmost term of the left
+** child is "something", and the leftmost term of the right child is
+** "wicked", only "w" is stored).
+**
+** New data is spilled to a new interior node at the same height when
+** the current node exceeds INTERIOR_MAX bytes (default 2048).
+** INTERIOR_MIN_TERMS (default 7) keeps large terms from monopolizing
+** interior nodes and making the tree too skinny.  The interior nodes
+** at a given height are naturally tracked by interior nodes at
+** height+1, and so on.
+**
+**
+**** Segment directory ****
+** The segment directory in table %_segdir stores meta-information for
+** merging and deleting segments, and also the root node of the
+** segment's tree.
+**
+** The root node is the top node of the segment's tree after encoding
+** the entire segment, restricted to ROOT_MAX bytes (default 1024).
+** This could be either a leaf node or an interior node.  If the top
+** node requires more than ROOT_MAX bytes, it is flushed to %_segments
+** and a new root interior node is generated (which should always fit
+** within ROOT_MAX because it only needs space for 2 varints, the
+** height and the blockid of the previous root).
+**
+** The meta-information in the segment directory is:
+**   level               - segment level (see below)
+**   idx                 - index within level
+**                       - (level,idx uniquely identify a segment)
+**   start_block         - first leaf node
+**   leaves_end_block    - last leaf node
+**   end_block           - last block (including interior nodes)
+**   root                - contents of root node
+**
+** If the root node is a leaf node, then start_block,
+** leaves_end_block, and end_block are all 0.
+**
+**
+**** Segment merging ****
+** To amortize update costs, segments are grouped into levels and
+** merged in batches.  Each increase in level represents exponentially
+** more documents.
+**
+** New documents (actually, document updates) are tokenized and
+** written individually (using LeafWriter) to a level 0 segment, with
+** incrementing idx.  When idx reaches MERGE_COUNT (default 16), all
+** level 0 segments are merged into a single level 1 segment.  Level 1
+** is populated like level 0, and eventually MERGE_COUNT level 1
+** segments are merged to a single level 2 segment (representing
+** MERGE_COUNT^2 updates), and so on.
+**
+** A segment merge traverses all segments at a given level in
+** parallel, performing a straightforward sorted merge.  Since segment
+** leaf nodes are written in to the %_segments table in order, this
+** merge traverses the underlying sqlite disk structures efficiently.
+** After the merge, all segment blocks from the merged level are
+** deleted.
+**
+** MERGE_COUNT controls how often we merge segments.  16 seems to be
+** somewhat of a sweet spot for insertion performance.  32 and 64 show
+** very similar performance numbers to 16 on insertion, though they're
+** a tiny bit slower (perhaps due to more overhead in merge-time
+** sorting).  8 is about 20% slower than 16, 4 about 50% slower than
+** 16, 2 about 66% slower than 16.
+**
+** At query time, high MERGE_COUNT increases the number of segments
+** which need to be scanned and merged.  For instance, with 100k docs
+** inserted:
+**
+**    MERGE_COUNT   segments
+**       16           25
+**        8           12
+**        4           10
+**        2            6
+**
+** This appears to have only a moderate impact on queries for very
+** frequent terms (which are somewhat dominated by segment merge
+** costs), and infrequent and non-existent terms still seem to be fast
+** even with many segments.
+**
+** TODO(shess) That said, it would be nice to have a better query-side
+** argument for MERGE_COUNT of 16.  Also, it is possible/likely that
+** optimizations to things like doclist merging will swing the sweet
+** spot around.
+**
+**
+**
+**** Handling of deletions and updates ****
+** Since we're using a segmented structure, with no docid-oriented
+** index into the term index, we clearly cannot simply update the term
+** index when a document is deleted or updated.  For deletions, we
+** write an empty doclist (varint(docid) varint(POS_END)), for updates
+** we simply write the new doclist.  Segment merges overwrite older
+** data for a particular docid with newer data, so deletes or updates
+** will eventually overtake the earlier data and knock it out.  The
+** query logic likewise merges doclists so that newer data knocks out
+** older data.
+**
+** TODO(shess) Provide a VACUUM type operation to clear out all
+** deletions and duplications.  This would basically be a forced merge
+** into a single segment.
+*/
+
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+
+#if defined(SQLITE_ENABLE_FTS3) && !defined(SQLITE_CORE)
+# define SQLITE_CORE 1
 #endif
 
+
+/************** Include fts3_expr.h in the middle of fts3.c ******************/
+/************** Begin file fts3_expr.h ***************************************/
 /*
-** The sqlite3KeywordCode function looks up an identifier to determine if
-** it is a keyword.  If it is a keyword, the token code of that keyword is 
-** returned.  If the input is not a keyword, TK_ID is returned.
+** 2008 Nov 28
 **
-** The implementation of this routine was generated by a program,
-** mkkeywordhash.h, located in the tool subdirectory of the distribution.
-** The output of the mkkeywordhash.c program is written into a file
-** named keywordhash.h and then included into this source file by
-** the #include below.
-*/
-/************** Include keywordhash.h in the middle of tokenize.c ************/
-/************** Begin file keywordhash.h *************************************/
-/***** This file contains automatically generated code ******
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** The code in this file has been automatically generated by
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-**     $Header: /sqlite/sqlite/tool/mkkeywordhash.c,v 1.31 2007/07/30 18:26:20 rse Exp $
+******************************************************************************
 **
-** The code in this file implements a function that determines whether
-** or not a given identifier is really an SQL keyword.  The same thing
-** might be implemented more directly using a hand-written hash table.
-** But by using this automatically generated code, the size of the code
-** is substantially reduced.  This is important for embedded applications
-** on platforms with limited memory.
 */
-/* Hash score: 165 */
-static int keywordCode(const char *z, int n){
-  /* zText[] encodes 775 bytes of keywords in 526 bytes */
-  static const char zText[526] =
-    "BEFOREIGNOREGEXPLAINSTEADDESCAPEACHECKEYCONSTRAINTERSECTABLEFT"
-    "HENDATABASELECTRANSACTIONATURALTERAISELSEXCEPTRIGGEREFERENCES"
-    "UNIQUERYATTACHAVINGROUPDATEMPORARYBEGINNEREINDEXCLUSIVEXISTSBETWEEN"
-    "OTNULLIKECASCADEFERRABLECASECOLLATECREATECURRENT_DATEDELETEDETACH"
-    "IMMEDIATEJOINSERTMATCHPLANALYZEPRAGMABORTVALUESVIRTUALIMITWHEN"
-    "WHERENAMEAFTEREPLACEANDEFAULTAUTOINCREMENTCASTCOLUMNCOMMITCONFLICT"
-    "CROSSCURRENT_TIMESTAMPRIMARYDEFERREDISTINCTDROPFAILFROMFULLGLOB"
-    "YIFINTOFFSETISNULLORDERESTRICTOUTERIGHTROLLBACKROWUNIONUSINGVACUUM"
-    "VIEWINITIALLY";
-  static const unsigned char aHash[127] = {
-      63,  92, 109,  61,   0,  38,   0,   0,  69,   0,  64,   0,   0,
-     102,   4,  65,   7,   0, 108,  72, 103,  99,   0,  22,   0,   0,
-     113,   0, 111, 106,   0,  18,  80,   0,   1,   0,   0,  56,  57,
-       0,  55,  11,   0,  33,  77,  89,   0, 110,  88,   0,   0,  45,
-       0,  90,  54,   0,  20,   0, 114,  34,  19,   0,  10,  97,  28,
-      83,   0,   0, 116,  93,  47, 115,  41,  12,  44,   0,  78,   0,
-      87,  29,   0,  86,   0,   0,   0,  82,  79,  84,  75,  96,   6,
-      14,  95,   0,  68,   0,  21,  76,  98,  27,   0, 112,  67, 104,
-      49,  40,  71,   0,   0,  81, 100,   0, 107,   0,  15,   0,   0,
-      24,   0,  73,  42,  50,   0,  16,  48,   0,  37,
-  };
-  static const unsigned char aNext[116] = {
-       0,   0,   0,   0,   0,   0,   0,   0,   0,   9,   0,   0,   0,
-       0,   0,   0,   0,   5,   0,   0,   0,   0,   0,   0,   0,   0,
-       0,   0,   0,   0,   0,   0,   0,   0,   0,   0,  32,   0,   0,
-      17,   0,   0,   0,  36,  39,   0,   0,  25,   0,   0,  31,   0,
-       0,   0,  43,  52,   0,   0,   0,  53,   0,   0,   0,   0,   0,
-       0,   0,   0,   0,  51,   0,   0,   0,   0,  26,   0,   8,  46,
-       2,   0,   0,   0,   0,   0,   0,   0,   3,  58,  66,   0,  13,
-       0,  91,  85,   0,  94,   0,  74,   0,   0,  62,   0,  35, 101,
-       0,   0, 105,  23,  30,  60,  70,   0,   0,  59,   0,   0,
-  };
-  static const unsigned char aLen[116] = {
-       6,   7,   3,   6,   6,   7,   7,   3,   4,   6,   4,   5,   3,
-      10,   9,   5,   4,   4,   3,   8,   2,   6,  11,   2,   7,   5,
-       5,   4,   6,   7,  10,   6,   5,   6,   6,   5,   6,   4,   9,
-       2,   5,   5,   7,   5,   9,   6,   7,   7,   3,   4,   4,   7,
-       3,  10,   4,   7,   6,  12,   6,   6,   9,   4,   6,   5,   4,
-       7,   6,   5,   6,   7,   5,   4,   5,   6,   5,   7,   3,   7,
-      13,   2,   2,   4,   6,   6,   8,   5,  17,  12,   7,   8,   8,
-       2,   4,   4,   4,   4,   4,   2,   2,   4,   6,   2,   3,   6,
-       5,   8,   5,   5,   8,   3,   5,   5,   6,   4,   9,   3,
-  };
-  static const unsigned short int aOffset[116] = {
-       0,   2,   2,   6,  10,  13,  18,  23,  25,  26,  31,  33,  37,
-      40,  47,  55,  58,  61,  63,  65,  70,  71,  76,  85,  86,  91,
-      95,  99, 102, 107, 113, 123, 126, 131, 136, 141, 144, 148, 148,
-     152, 157, 160, 164, 166, 169, 177, 183, 189, 189, 192, 195, 199,
-     200, 204, 214, 218, 225, 231, 243, 249, 255, 264, 266, 272, 277,
-     279, 286, 291, 296, 302, 308, 313, 317, 320, 326, 330, 337, 339,
-     346, 348, 350, 359, 363, 369, 375, 383, 388, 388, 404, 411, 418,
-     419, 426, 430, 434, 438, 442, 445, 447, 449, 452, 452, 455, 458,
-     464, 468, 476, 480, 485, 493, 496, 501, 506, 512, 516, 521,
-  };
-  static const unsigned char aCode[116] = {
-    TK_BEFORE,     TK_FOREIGN,    TK_FOR,        TK_IGNORE,     TK_LIKE_KW,    
-    TK_EXPLAIN,    TK_INSTEAD,    TK_ADD,        TK_DESC,       TK_ESCAPE,     
-    TK_EACH,       TK_CHECK,      TK_KEY,        TK_CONSTRAINT, TK_INTERSECT,  
-    TK_TABLE,      TK_JOIN_KW,    TK_THEN,       TK_END,        TK_DATABASE,   
-    TK_AS,         TK_SELECT,     TK_TRANSACTION,TK_ON,         TK_JOIN_KW,    
-    TK_ALTER,      TK_RAISE,      TK_ELSE,       TK_EXCEPT,     TK_TRIGGER,    
-    TK_REFERENCES, TK_UNIQUE,     TK_QUERY,      TK_ATTACH,     TK_HAVING,     
-    TK_GROUP,      TK_UPDATE,     TK_TEMP,       TK_TEMP,       TK_OR,         
-    TK_BEGIN,      TK_JOIN_KW,    TK_REINDEX,    TK_INDEX,      TK_EXCLUSIVE,  
-    TK_EXISTS,     TK_BETWEEN,    TK_NOTNULL,    TK_NOT,        TK_NULL,       
-    TK_LIKE_KW,    TK_CASCADE,    TK_ASC,        TK_DEFERRABLE, TK_CASE,       
-    TK_COLLATE,    TK_CREATE,     TK_CTIME_KW,   TK_DELETE,     TK_DETACH,     
-    TK_IMMEDIATE,  TK_JOIN,       TK_INSERT,     TK_MATCH,      TK_PLAN,       
-    TK_ANALYZE,    TK_PRAGMA,     TK_ABORT,      TK_VALUES,     TK_VIRTUAL,    
-    TK_LIMIT,      TK_WHEN,       TK_WHERE,      TK_RENAME,     TK_AFTER,      
-    TK_REPLACE,    TK_AND,        TK_DEFAULT,    TK_AUTOINCR,   TK_TO,         
-    TK_IN,         TK_CAST,       TK_COLUMNKW,   TK_COMMIT,     TK_CONFLICT,   
-    TK_JOIN_KW,    TK_CTIME_KW,   TK_CTIME_KW,   TK_PRIMARY,    TK_DEFERRED,   
-    TK_DISTINCT,   TK_IS,         TK_DROP,       TK_FAIL,       TK_FROM,       
-    TK_JOIN_KW,    TK_LIKE_KW,    TK_BY,         TK_IF,         TK_INTO,       
-    TK_OFFSET,     TK_OF,         TK_SET,        TK_ISNULL,     TK_ORDER,      
-    TK_RESTRICT,   TK_JOIN_KW,    TK_JOIN_KW,    TK_ROLLBACK,   TK_ROW,        
-    TK_UNION,      TK_USING,      TK_VACUUM,     TK_VIEW,       TK_INITIALLY,  
-    TK_ALL,        
-  };
-  int h, i;
-  if( n<2 ) return TK_ID;
-  h = ((charMap(z[0])*4) ^
-      (charMap(z[n-1])*3) ^
-      n) % 127;
-  for(i=((int)aHash[h])-1; i>=0; i=((int)aNext[i])-1){
-    if( aLen[i]==n && sqlite3StrNICmp(&zText[aOffset[i]],z,n)==0 ){
-      return aCode[i];
-    }
-  }
-  return TK_ID;
-}
-SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char *z, int n){
-  return keywordCode((char*)z, n);
-}
-
-/************** End of keywordhash.h *****************************************/
-/************** Continuing where we left off in tokenize.c *******************/
-
 
+/************** Include fts3_tokenizer.h in the middle of fts3_expr.h ********/
+/************** Begin file fts3_tokenizer.h **********************************/
 /*
-** If X is a character that can be used in an identifier then
-** IdChar(X) will be true.  Otherwise it is false.
+** 2006 July 10
 **
-** For ASCII, any character with the high-order bit set is
-** allowed in an identifier.  For 7-bit characters, 
-** sqlite3IsIdChar[X] must be 1.
+** The author disclaims copyright to this source code.
 **
-** For EBCDIC, the rules are more complex but have the same
-** end result.
+*************************************************************************
+** Defines the interface to tokenizers used by fulltext-search.  There
+** are three basic components:
 **
-** Ticket #1066.  the SQL standard does not allow '$' in the
-** middle of identfiers.  But many SQL implementations do. 
-** SQLite will allow '$' in identifiers for compatibility.
-** But the feature is undocumented.
+** sqlite3_tokenizer_module is a singleton defining the tokenizer
+** interface functions.  This is essentially the class structure for
+** tokenizers.
+**
+** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
+** including customization information defined at creation time.
+**
+** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
+** tokens from a particular input.
 */
-#ifdef SQLITE_ASCII
-SQLITE_PRIVATE const char sqlite3IsAsciiIdChar[] = {
-/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
-    0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* 2x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
-};
-#define IdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && sqlite3IsAsciiIdChar[c-0x20]))
-#endif
-#ifdef SQLITE_EBCDIC
-SQLITE_PRIVATE const char sqlite3IsEbcdicIdChar[] = {
-/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
-    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 4x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0,  /* 5x */
-    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0,  /* 6x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,  /* 7x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0,  /* 8x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0,  /* 9x */
-    1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0,  /* Ax */
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* Bx */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Cx */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Dx */
-    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Ex */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0,  /* Fx */
-};
-#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
-#endif
-
+#ifndef _FTS3_TOKENIZER_H_
+#define _FTS3_TOKENIZER_H_
 
-/*
-** Return the length of the token that begins at z[0]. 
-** Store the token type in *tokenType before returning.
+/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
+** If tokenizers are to be allowed to call sqlite3_*() functions, then
+** we will need a way to register the API consistently.
 */
-SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
-  int i, c;
-  switch( *z ){
-    case ' ': case '\t': case '\n': case '\f': case '\r': {
-      for(i=1; isspace(z[i]); i++){}
-      *tokenType = TK_SPACE;
-      return i;
-    }
-    case '-': {
-      if( z[1]=='-' ){
-        for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
-        *tokenType = TK_COMMENT;
-        return i;
-      }
-      *tokenType = TK_MINUS;
-      return 1;
-    }
-    case '(': {
-      *tokenType = TK_LP;
-      return 1;
-    }
-    case ')': {
-      *tokenType = TK_RP;
-      return 1;
-    }
-    case ';': {
-      *tokenType = TK_SEMI;
-      return 1;
-    }
-    case '+': {
-      *tokenType = TK_PLUS;
-      return 1;
-    }
-    case '*': {
-      *tokenType = TK_STAR;
-      return 1;
-    }
-    case '/': {
-      if( z[1]!='*' || z[2]==0 ){
-        *tokenType = TK_SLASH;
-        return 1;
-      }
-      for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
-      if( c ) i++;
-      *tokenType = TK_COMMENT;
-      return i;
-    }
-    case '%': {
-      *tokenType = TK_REM;
-      return 1;
-    }
-    case '=': {
-      *tokenType = TK_EQ;
-      return 1 + (z[1]=='=');
-    }
-    case '<': {
-      if( (c=z[1])=='=' ){
-        *tokenType = TK_LE;
-        return 2;
-      }else if( c=='>' ){
-        *tokenType = TK_NE;
-        return 2;
-      }else if( c=='<' ){
-        *tokenType = TK_LSHIFT;
-        return 2;
-      }else{
-        *tokenType = TK_LT;
-        return 1;
-      }
-    }
-    case '>': {
-      if( (c=z[1])=='=' ){
-        *tokenType = TK_GE;
-        return 2;
-      }else if( c=='>' ){
-        *tokenType = TK_RSHIFT;
-        return 2;
-      }else{
-        *tokenType = TK_GT;
-        return 1;
-      }
-    }
-    case '!': {
-      if( z[1]!='=' ){
-        *tokenType = TK_ILLEGAL;
-        return 2;
-      }else{
-        *tokenType = TK_NE;
-        return 2;
-      }
-    }
-    case '|': {
-      if( z[1]!='|' ){
-        *tokenType = TK_BITOR;
-        return 1;
-      }else{
-        *tokenType = TK_CONCAT;
-        return 2;
-      }
-    }
-    case ',': {
-      *tokenType = TK_COMMA;
-      return 1;
-    }
-    case '&': {
-      *tokenType = TK_BITAND;
-      return 1;
-    }
-    case '~': {
-      *tokenType = TK_BITNOT;
-      return 1;
-    }
-    case '`':
-    case '\'':
-    case '"': {
-      int delim = z[0];
-      for(i=1; (c=z[i])!=0; i++){
-        if( c==delim ){
-          if( z[i+1]==delim ){
-            i++;
-          }else{
-            break;
-          }
-        }
-      }
-      if( c ){
-        *tokenType = TK_STRING;
-        return i+1;
-      }else{
-        *tokenType = TK_ILLEGAL;
-        return i;
-      }
-    }
-    case '.': {
-#ifndef SQLITE_OMIT_FLOATING_POINT
-      if( !isdigit(z[1]) )
-#endif
-      {
-        *tokenType = TK_DOT;
-        return 1;
-      }
-      /* If the next character is a digit, this is a floating point
-      ** number that begins with ".".  Fall thru into the next case */
-    }
-    case '0': case '1': case '2': case '3': case '4':
-    case '5': case '6': case '7': case '8': case '9': {
-      *tokenType = TK_INTEGER;
-      for(i=0; isdigit(z[i]); i++){}
-#ifndef SQLITE_OMIT_FLOATING_POINT
-      if( z[i]=='.' ){
-        i++;
-        while( isdigit(z[i]) ){ i++; }
-        *tokenType = TK_FLOAT;
-      }
-      if( (z[i]=='e' || z[i]=='E') &&
-           ( isdigit(z[i+1]) 
-            || ((z[i+1]=='+' || z[i+1]=='-') && isdigit(z[i+2]))
-           )
-      ){
-        i += 2;
-        while( isdigit(z[i]) ){ i++; }
-        *tokenType = TK_FLOAT;
-      }
-#endif
-      while( IdChar(z[i]) ){
-        *tokenType = TK_ILLEGAL;
-        i++;
-      }
-      return i;
-    }
-    case '[': {
-      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
-      *tokenType = c==']' ? TK_ID : TK_ILLEGAL;
-      return i;
-    }
-    case '?': {
-      *tokenType = TK_VARIABLE;
-      for(i=1; isdigit(z[i]); i++){}
-      return i;
-    }
-    case '#': {
-      for(i=1; isdigit(z[i]); i++){}
-      if( i>1 ){
-        /* Parameters of the form #NNN (where NNN is a number) are used
-        ** internally by sqlite3NestedParse.  */
-        *tokenType = TK_REGISTER;
-        return i;
-      }
-      /* Fall through into the next case if the '#' is not followed by
-      ** a digit. Try to match #AAAA where AAAA is a parameter name. */
-    }
-#ifndef SQLITE_OMIT_TCL_VARIABLE
-    case '$':
-#endif
-    case '@':  /* For compatibility with MS SQL Server */
-    case ':': {
-      int n = 0;
-      *tokenType = TK_VARIABLE;
-      for(i=1; (c=z[i])!=0; i++){
-        if( IdChar(c) ){
-          n++;
-#ifndef SQLITE_OMIT_TCL_VARIABLE
-        }else if( c=='(' && n>0 ){
-          do{
-            i++;
-          }while( (c=z[i])!=0 && !isspace(c) && c!=')' );
-          if( c==')' ){
-            i++;
-          }else{
-            *tokenType = TK_ILLEGAL;
-          }
-          break;
-        }else if( c==':' && z[i+1]==':' ){
-          i++;
-#endif
-        }else{
-          break;
-        }
-      }
-      if( n==0 ) *tokenType = TK_ILLEGAL;
-      return i;
-    }
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-    case 'x': case 'X': {
-      if( z[1]=='\'' ){
-        *tokenType = TK_BLOB;
-        for(i=2; (c=z[i])!=0 && c!='\''; i++){
-          if( !isxdigit(c) ){
-            *tokenType = TK_ILLEGAL;
-          }
-        }
-        if( i%2 || !c ) *tokenType = TK_ILLEGAL;
-        if( c ) i++;
-        return i;
-      }
-      /* Otherwise fall through to the next case */
-    }
-#endif
-    default: {
-      if( !IdChar(*z) ){
-        break;
-      }
-      for(i=1; IdChar(z[i]); i++){}
-      *tokenType = keywordCode((char*)z, i);
-      return i;
-    }
-  }
-  *tokenType = TK_ILLEGAL;
-  return 1;
-}
 
 /*
-** Run the parser on the given SQL string.  The parser structure is
-** passed in.  An SQLITE_ status code is returned.  If an error occurs
-** and pzErrMsg!=NULL then an error message might be written into 
-** memory obtained from sqlite3_malloc() and *pzErrMsg made to point to that
-** error message.  Or maybe not.
+** Structures used by the tokenizer interface. When a new tokenizer
+** implementation is registered, the caller provides a pointer to
+** an sqlite3_tokenizer_module containing pointers to the callback
+** functions that make up an implementation.
+**
+** When an fts3 table is created, it passes any arguments passed to
+** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
+** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
+** implementation. The xCreate() function in turn returns an 
+** sqlite3_tokenizer structure representing the specific tokenizer to
+** be used for the fts3 table (customized by the tokenizer clause arguments).
+**
+** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
+** method is called. It returns an sqlite3_tokenizer_cursor object
+** that may be used to tokenize a specific input buffer based on
+** the tokenization rules supplied by a specific sqlite3_tokenizer
+** object.
 */
-SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
-  int nErr = 0;
-  int i;
-  void *pEngine;
-  int tokenType;
-  int lastTokenParsed = -1;
-  sqlite3 *db = pParse->db;
-  int mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
+typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
+typedef struct sqlite3_tokenizer sqlite3_tokenizer;
+typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
 
-  if( db->activeVdbeCnt==0 ){
-    db->u1.isInterrupted = 0;
-  }
-  pParse->rc = SQLITE_OK;
-  pParse->zTail = pParse->zSql = zSql;
-  i = 0;
-  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3_malloc);
-  if( pEngine==0 ){
-    db->mallocFailed = 1;
-    return SQLITE_NOMEM;
-  }
-  assert( pParse->sLastToken.dyn==0 );
-  assert( pParse->pNewTable==0 );
-  assert( pParse->pNewTrigger==0 );
-  assert( pParse->nVar==0 );
-  assert( pParse->nVarExpr==0 );
-  assert( pParse->nVarExprAlloc==0 );
-  assert( pParse->apVarExpr==0 );
-  while( !db->mallocFailed && zSql[i]!=0 ){
-    assert( i>=0 );
-    pParse->sLastToken.z = (u8*)&zSql[i];
-    assert( pParse->sLastToken.dyn==0 );
-    pParse->sLastToken.n = sqlite3GetToken((unsigned char*)&zSql[i],&tokenType);
-    i += pParse->sLastToken.n;
-    if( i>mxSqlLen ){
-      pParse->rc = SQLITE_TOOBIG;
-      break;
-    }
-    switch( tokenType ){
-      case TK_SPACE:
-      case TK_COMMENT: {
-        if( db->u1.isInterrupted ){
-          pParse->rc = SQLITE_INTERRUPT;
-          sqlite3SetString(pzErrMsg, "interrupt", (char*)0);
-          goto abort_parse;
-        }
-        break;
-      }
-      case TK_ILLEGAL: {
-        if( pzErrMsg ){
-          sqlite3_free(*pzErrMsg);
-          *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"",
-                          &pParse->sLastToken);
-        }
-        nErr++;
-        goto abort_parse;
-      }
-      case TK_SEMI: {
-        pParse->zTail = &zSql[i];
-        /* Fall thru into the default case */
-      }
-      default: {
-        sqlite3Parser(pEngine, tokenType, pParse->sLastToken, pParse);
-        lastTokenParsed = tokenType;
-        if( pParse->rc!=SQLITE_OK ){
-          goto abort_parse;
-        }
-        break;
-      }
-    }
-  }
-abort_parse:
-  if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
-    if( lastTokenParsed!=TK_SEMI ){
-      sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
-      pParse->zTail = &zSql[i];
-    }
-    sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
-  }
-  sqlite3ParserFree(pEngine, sqlite3_free);
-  if( db->mallocFailed ){
-    pParse->rc = SQLITE_NOMEM;
-  }
-  if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
-    sqlite3SetString(&pParse->zErrMsg, sqlite3ErrStr(pParse->rc), (char*)0);
-  }
-  if( pParse->zErrMsg ){
-    if( pzErrMsg && *pzErrMsg==0 ){
-      *pzErrMsg = pParse->zErrMsg;
-    }else{
-      sqlite3_free(pParse->zErrMsg);
-    }
-    pParse->zErrMsg = 0;
-    nErr++;
-  }
-  if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
-    sqlite3VdbeDelete(pParse->pVdbe);
-    pParse->pVdbe = 0;
-  }
-#ifndef SQLITE_OMIT_SHARED_CACHE
-  if( pParse->nested==0 ){
-    sqlite3_free(pParse->aTableLock);
-    pParse->aTableLock = 0;
-    pParse->nTableLock = 0;
-  }
-#endif
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3_free(pParse->apVtabLock);
-#endif
+struct sqlite3_tokenizer_module {
+
+  /*
+  ** Structure version. Should always be set to 0.
+  */
+  int iVersion;
+
+  /*
+  ** Create a new tokenizer. The values in the argv[] array are the
+  ** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
+  ** TABLE statement that created the fts3 table. For example, if
+  ** the following SQL is executed:
+  **
+  **   CREATE .. USING fts3( ... , tokenizer <tokenizer-name> arg1 arg2)
+  **
+  ** then argc is set to 2, and the argv[] array contains pointers
+  ** to the strings "arg1" and "arg2".
+  **
+  ** This method should return either SQLITE_OK (0), or an SQLite error 
+  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
+  ** to point at the newly created tokenizer structure. The generic
+  ** sqlite3_tokenizer.pModule variable should not be initialised by
+  ** this callback. The caller will do so.
+  */
+  int (*xCreate)(
+    int argc,                           /* Size of argv array */
+    const char *const*argv,             /* Tokenizer argument strings */
+    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
+  );
+
+  /*
+  ** Destroy an existing tokenizer. The fts3 module calls this method
+  ** exactly once for each successful call to xCreate().
+  */
+  int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
+
+  /*
+  ** Create a tokenizer cursor to tokenize an input buffer. The caller
+  ** is responsible for ensuring that the input buffer remains valid
+  ** until the cursor is closed (using the xClose() method). 
+  */
+  int (*xOpen)(
+    sqlite3_tokenizer *pTokenizer,       /* Tokenizer object */
+    const char *pInput, int nBytes,      /* Input buffer */
+    sqlite3_tokenizer_cursor **ppCursor  /* OUT: Created tokenizer cursor */
+  );
 
-  if( !IN_DECLARE_VTAB ){
-    /* If the pParse->declareVtab flag is set, do not delete any table 
-    ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
-    ** will take responsibility for freeing the Table structure.
-    */
-    sqlite3DeleteTable(pParse->pNewTable);
-  }
+  /*
+  ** Destroy an existing tokenizer cursor. The fts3 module calls this 
+  ** method exactly once for each successful call to xOpen().
+  */
+  int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
 
-  sqlite3DeleteTrigger(pParse->pNewTrigger);
-  sqlite3_free(pParse->apVarExpr);
-  if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
-    pParse->rc = SQLITE_ERROR;
-  }
-  return nErr;
-}
+  /*
+  ** Retrieve the next token from the tokenizer cursor pCursor. This
+  ** method should either return SQLITE_OK and set the values of the
+  ** "OUT" variables identified below, or SQLITE_DONE to indicate that
+  ** the end of the buffer has been reached, or an SQLite error code.
+  **
+  ** *ppToken should be set to point at a buffer containing the 
+  ** normalized version of the token (i.e. after any case-folding and/or
+  ** stemming has been performed). *pnBytes should be set to the length
+  ** of this buffer in bytes. The input text that generated the token is
+  ** identified by the byte offsets returned in *piStartOffset and
+  ** *piEndOffset. *piStartOffset should be set to the index of the first
+  ** byte of the token in the input buffer. *piEndOffset should be set
+  ** to the index of the first byte just past the end of the token in
+  ** the input buffer.
+  **
+  ** The buffer *ppToken is set to point at is managed by the tokenizer
+  ** implementation. It is only required to be valid until the next call
+  ** to xNext() or xClose(). 
+  */
+  /* TODO(shess) current implementation requires pInput to be
+  ** nul-terminated.  This should either be fixed, or pInput/nBytes
+  ** should be converted to zInput.
+  */
+  int (*xNext)(
+    sqlite3_tokenizer_cursor *pCursor,   /* Tokenizer cursor */
+    const char **ppToken, int *pnBytes,  /* OUT: Normalized text for token */
+    int *piStartOffset,  /* OUT: Byte offset of token in input buffer */
+    int *piEndOffset,    /* OUT: Byte offset of end of token in input buffer */
+    int *piPosition      /* OUT: Number of tokens returned before this one */
+  );
+};
+
+struct sqlite3_tokenizer {
+  const sqlite3_tokenizer_module *pModule;  /* The module for this tokenizer */
+  /* Tokenizer implementations will typically add additional fields */
+};
+
+struct sqlite3_tokenizer_cursor {
+  sqlite3_tokenizer *pTokenizer;       /* Tokenizer for this cursor. */
+  /* Tokenizer implementations will typically add additional fields */
+};
+
+#endif /* _FTS3_TOKENIZER_H_ */
+
+/************** End of fts3_tokenizer.h **************************************/
+/************** Continuing where we left off in fts3_expr.h ******************/
 
-/************** End of tokenize.c ********************************************/
-/************** Begin file complete.c ****************************************/
 /*
-** 2001 September 15
+** The following describes the syntax supported by the fts3 MATCH
+** operator in a similar format to that used by the lemon parser
+** generator. This module does not use actually lemon, it uses a
+** custom parser.
 **
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+**   query ::= andexpr (OR andexpr)*.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+**   andexpr ::= notexpr (AND? notexpr)*.
 **
-*************************************************************************
-** An tokenizer for SQL
+**   notexpr ::= nearexpr (NOT nearexpr|-TOKEN)*.
+**   notexpr ::= LP query RP.
 **
-** This file contains C code that implements the sqlite3_complete() API.
-** This code used to be part of the tokenizer.c source file.  But by
-** separating it out, the code will be automatically omitted from
-** static links that do not use it.
+**   nearexpr ::= phrase (NEAR distance_opt nearexpr)*.
+**
+**   distance_opt ::= .
+**   distance_opt ::= / INTEGER.
 **
-** $Id: complete.c,v 1.6 2007/08/27 23:26:59 drh Exp $
+**   phrase ::= TOKEN.
+**   phrase ::= COLUMN:TOKEN.
+**   phrase ::= "TOKEN TOKEN TOKEN...".
 */
-#ifndef SQLITE_OMIT_COMPLETE
+
+typedef struct Fts3Expr Fts3Expr;
+typedef struct Fts3Phrase Fts3Phrase;
 
 /*
-** This is defined in tokenize.c.  We just have to import the definition.
+** A "phrase" is a sequence of one or more tokens that must match in
+** sequence.  A single token is the base case and the most common case.
+** For a sequence of tokens contained in "...", nToken will be the number
+** of tokens in the string.
 */
-#ifndef SQLITE_AMALGAMATION
-#ifdef SQLITE_ASCII
-SQLITE_PRIVATE const char sqlite3IsAsciiIdChar[];
-#define IdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && sqlite3IsAsciiIdChar[c-0x20]))
-#endif
-#ifdef SQLITE_EBCDIC
-SQLITE_PRIVATE const char sqlite3IsEbcdicIdChar[];
-#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
-#endif
-#endif /* SQLITE_AMALGAMATION */
-
+struct Fts3Phrase {
+  int nToken;          /* Number of tokens in the phrase */
+  int iColumn;         /* Index of column this phrase must match */
+  int isNot;           /* Phrase prefixed by unary not (-) operator */
+  struct PhraseToken {
+    char *z;              /* Text of the token */
+    int n;                /* Number of bytes in buffer pointed to by z */
+    int isPrefix;         /* True if token ends in with a "*" character */
+  } aToken[1];         /* One entry for each token in the phrase */
+};
 
 /*
-** Token types used by the sqlite3_complete() routine.  See the header
-** comments on that procedure for additional information.
+** A tree of these objects forms the RHS of a MATCH operator.
 */
-#define tkSEMI    0
-#define tkWS      1
-#define tkOTHER   2
-#define tkEXPLAIN 3
-#define tkCREATE  4
-#define tkTEMP    5
-#define tkTRIGGER 6
-#define tkEND     7
+struct Fts3Expr {
+  int eType;                 /* One of the FTSQUERY_XXX values defined below */
+  int nNear;                 /* Valid if eType==FTSQUERY_NEAR */
+  Fts3Expr *pParent;         /* pParent->pLeft==this or pParent->pRight==this */
+  Fts3Expr *pLeft;           /* Left operand */
+  Fts3Expr *pRight;          /* Right operand */
+  Fts3Phrase *pPhrase;       /* Valid if eType==FTSQUERY_PHRASE */
+};
+
+SQLITE_PRIVATE int sqlite3Fts3ExprParse(sqlite3_tokenizer *, char **, int, int, 
+                         const char *, int, Fts3Expr **);
+SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *);
 
 /*
-** Return TRUE if the given SQL string ends in a semicolon.
+** Candidate values for Fts3Query.eType. Note that the order of the first
+** four values is in order of precedence when parsing expressions. For 
+** example, the following:
 **
-** Special handling is require for CREATE TRIGGER statements.
-** Whenever the CREATE TRIGGER keywords are seen, the statement
-** must end with ";END;".
+**   "a OR b AND c NOT d NEAR e"
 **
-** This implementation uses a state machine with 7 states:
+** is equivalent to:
 **
-**   (0) START     At the beginning or end of an SQL statement.  This routine
-**                 returns 1 if it ends in the START state and 0 if it ends
-**                 in any other state.
+**   "a OR (b AND (c NOT (d NEAR e)))"
+*/
+#define FTSQUERY_NEAR   1
+#define FTSQUERY_NOT    2
+#define FTSQUERY_AND    3
+#define FTSQUERY_OR     4
+#define FTSQUERY_PHRASE 5
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE void sqlite3Fts3ExprInitTestInterface(sqlite3 *db);
+#endif
+
+/************** End of fts3_expr.h *******************************************/
+/************** Continuing where we left off in fts3.c ***********************/
+/************** Include fts3_hash.h in the middle of fts3.c ******************/
+/************** Begin file fts3_hash.h ***************************************/
+/*
+** 2001 September 22
 **
-**   (1) NORMAL    We are in the middle of statement which ends with a single
-**                 semicolon.
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-**   (2) EXPLAIN   The keyword EXPLAIN has been seen at the beginning of 
-**                 a statement.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-**   (3) CREATE    The keyword CREATE has been seen at the beginning of a
-**                 statement, possibly preceeded by EXPLAIN and/or followed by
-**                 TEMP or TEMPORARY
+*************************************************************************
+** This is the header file for the generic hash-table implemenation
+** used in SQLite.  We've modified it slightly to serve as a standalone
+** hash table implementation for the full-text indexing module.
 **
-**   (4) TRIGGER   We are in the middle of a trigger definition that must be
-**                 ended by a semicolon, the keyword END, and another semicolon.
+*/
+#ifndef _FTS3_HASH_H_
+#define _FTS3_HASH_H_
+
+/* Forward declarations of structures. */
+typedef struct fts3Hash fts3Hash;
+typedef struct fts3HashElem fts3HashElem;
+
+/* A complete hash table is an instance of the following structure.
+** The internals of this structure are intended to be opaque -- client
+** code should not attempt to access or modify the fields of this structure
+** directly.  Change this structure only by using the routines below.
+** However, many of the "procedures" and "functions" for modifying and
+** accessing this structure are really macros, so we can't really make
+** this structure opaque.
+*/
+struct fts3Hash {
+  char keyClass;          /* HASH_INT, _POINTER, _STRING, _BINARY */
+  char copyKey;           /* True if copy of key made on insert */
+  int count;              /* Number of entries in this table */
+  fts3HashElem *first;    /* The first element of the array */
+  int htsize;             /* Number of buckets in the hash table */
+  struct _fts3ht {        /* the hash table */
+    int count;               /* Number of entries with this hash */
+    fts3HashElem *chain;     /* Pointer to first entry with this hash */
+  } *ht;
+};
+
+/* Each element in the hash table is an instance of the following 
+** structure.  All elements are stored on a single doubly-linked list.
 **
-**   (5) SEMI      We've seen the first semicolon in the ";END;" that occurs at
-**                 the end of a trigger definition.
+** Again, this structure is intended to be opaque, but it can't really
+** be opaque because it is used by macros.
+*/
+struct fts3HashElem {
+  fts3HashElem *next, *prev; /* Next and previous elements in the table */
+  void *data;                /* Data associated with this element */
+  void *pKey; int nKey;      /* Key associated with this element */
+};
+
+/*
+** There are 2 different modes of operation for a hash table:
 **
-**   (6) END       We've seen the ";END" of the ";END;" that occurs at the end
-**                 of a trigger difinition.
+**   FTS3_HASH_STRING        pKey points to a string that is nKey bytes long
+**                           (including the null-terminator, if any).  Case
+**                           is respected in comparisons.
 **
-** Transitions between states above are determined by tokens extracted
-** from the input.  The following tokens are significant:
+**   FTS3_HASH_BINARY        pKey points to binary data nKey bytes long. 
+**                           memcmp() is used to compare keys.
 **
-**   (0) tkSEMI      A semicolon.
-**   (1) tkWS        Whitespace
-**   (2) tkOTHER     Any other SQL token.
-**   (3) tkEXPLAIN   The "explain" keyword.
-**   (4) tkCREATE    The "create" keyword.
-**   (5) tkTEMP      The "temp" or "temporary" keyword.
-**   (6) tkTRIGGER   The "trigger" keyword.
-**   (7) tkEND       The "end" keyword.
+** A copy of the key is made if the copyKey parameter to fts3HashInit is 1.  
+*/
+#define FTS3_HASH_STRING    1
+#define FTS3_HASH_BINARY    2
+
+/*
+** Access routines.  To delete, insert a NULL pointer.
+*/
+SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash*, int keytype, int copyKey);
+SQLITE_PRIVATE void *sqlite3Fts3HashInsert(fts3Hash*, const void *pKey, int nKey, void *pData);
+SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash*, const void *pKey, int nKey);
+SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash*);
+
+/*
+** Shorthand for the functions above
+*/
+#define fts3HashInit   sqlite3Fts3HashInit
+#define fts3HashInsert sqlite3Fts3HashInsert
+#define fts3HashFind   sqlite3Fts3HashFind
+#define fts3HashClear  sqlite3Fts3HashClear
+
+/*
+** Macros for looping over all elements of a hash table.  The idiom is
+** like this:
 **
-** Whitespace never causes a state transition and is always ignored.
+**   fts3Hash h;
+**   fts3HashElem *p;
+**   ...
+**   for(p=fts3HashFirst(&h); p; p=fts3HashNext(p)){
+**     SomeStructure *pData = fts3HashData(p);
+**     // do something with pData
+**   }
+*/
+#define fts3HashFirst(H)  ((H)->first)
+#define fts3HashNext(E)   ((E)->next)
+#define fts3HashData(E)   ((E)->data)
+#define fts3HashKey(E)    ((E)->pKey)
+#define fts3HashKeysize(E) ((E)->nKey)
+
+/*
+** Number of entries in a hash table
+*/
+#define fts3HashCount(H)  ((H)->count)
+
+#endif /* _FTS3_HASH_H_ */
+
+/************** End of fts3_hash.h *******************************************/
+/************** Continuing where we left off in fts3.c ***********************/
+#ifndef SQLITE_CORE 
+  SQLITE_EXTENSION_INIT1
+#endif
+
+
+/* TODO(shess) MAN, this thing needs some refactoring.  At minimum, it
+** would be nice to order the file better, perhaps something along the
+** lines of:
 **
-** If we compile with SQLITE_OMIT_TRIGGER, all of the computation needed
-** to recognize the end of a trigger can be omitted.  All we have to do
-** is look for a semicolon that is not part of an string or comment.
+**  - utility functions
+**  - table setup functions
+**  - table update functions
+**  - table query functions
+**
+** Put the query functions last because they're likely to reference
+** typedefs or functions from the table update section.
 */
-SQLITE_API int sqlite3_complete(const char *zSql){
-  u8 state = 0;   /* Current state, using numbers defined in header comment */
-  u8 token;       /* Value of the next token */
 
-#ifndef SQLITE_OMIT_TRIGGER
-  /* A complex statement machine used to detect the end of a CREATE TRIGGER
-  ** statement.  This is the normal case.
-  */
-  static const u8 trans[7][8] = {
-                     /* Token:                                                */
-     /* State:       **  SEMI  WS  OTHER EXPLAIN  CREATE  TEMP  TRIGGER  END  */
-     /* 0   START: */ {    0,  0,     1,      2,      3,    1,       1,   1,  },
-     /* 1  NORMAL: */ {    0,  1,     1,      1,      1,    1,       1,   1,  },
-     /* 2 EXPLAIN: */ {    0,  2,     1,      1,      3,    1,       1,   1,  },
-     /* 3  CREATE: */ {    0,  3,     1,      1,      1,    3,       4,   1,  },
-     /* 4 TRIGGER: */ {    5,  4,     4,      4,      4,    4,       4,   4,  },
-     /* 5    SEMI: */ {    5,  5,     4,      4,      4,    4,       4,   6,  },
-     /* 6     END: */ {    0,  6,     4,      4,      4,    4,       4,   4,  },
-  };
+#if 0
+# define FTSTRACE(A)  printf A; fflush(stdout)
 #else
-  /* If triggers are not suppored by this compile then the statement machine
-  ** used to detect the end of a statement is much simplier
-  */
-  static const u8 trans[2][3] = {
-                     /* Token:           */
-     /* State:       **  SEMI  WS  OTHER */
-     /* 0   START: */ {    0,  0,     1, },
-     /* 1  NORMAL: */ {    0,  1,     1, },
-  };
-#endif /* SQLITE_OMIT_TRIGGER */
+# define FTSTRACE(A)
+#endif
 
-  while( *zSql ){
-    switch( *zSql ){
-      case ';': {  /* A semicolon */
-        token = tkSEMI;
-        break;
-      }
-      case ' ':
-      case '\r':
-      case '\t':
-      case '\n':
-      case '\f': {  /* White space is ignored */
-        token = tkWS;
-        break;
-      }
-      case '/': {   /* C-style comments */
-        if( zSql[1]!='*' ){
-          token = tkOTHER;
-          break;
-        }
-        zSql += 2;
-        while( zSql[0] && (zSql[0]!='*' || zSql[1]!='/') ){ zSql++; }
-        if( zSql[0]==0 ) return 0;
-        zSql++;
-        token = tkWS;
-        break;
-      }
-      case '-': {   /* SQL-style comments from "--" to end of line */
-        if( zSql[1]!='-' ){
-          token = tkOTHER;
-          break;
-        }
-        while( *zSql && *zSql!='\n' ){ zSql++; }
-        if( *zSql==0 ) return state==0;
-        token = tkWS;
-        break;
-      }
-      case '[': {   /* Microsoft-style identifiers in [...] */
-        zSql++;
-        while( *zSql && *zSql!=']' ){ zSql++; }
-        if( *zSql==0 ) return 0;
-        token = tkOTHER;
-        break;
-      }
-      case '`':     /* Grave-accent quoted symbols used by MySQL */
-      case '"':     /* single- and double-quoted strings */
-      case '\'': {
-        int c = *zSql;
-        zSql++;
-        while( *zSql && *zSql!=c ){ zSql++; }
-        if( *zSql==0 ) return 0;
-        token = tkOTHER;
-        break;
-      }
-      default: {
-        int c;
-        if( IdChar((u8)*zSql) ){
-          /* Keywords and unquoted identifiers */
-          int nId;
-          for(nId=1; IdChar(zSql[nId]); nId++){}
-#ifdef SQLITE_OMIT_TRIGGER
-          token = tkOTHER;
+/* It is not safe to call isspace(), tolower(), or isalnum() on
+** hi-bit-set characters.  This is the same solution used in the
+** tokenizer.
+*/
+/* TODO(shess) The snippet-generation code should be using the
+** tokenizer-generated tokens rather than doing its own local
+** tokenization.
+*/
+/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
+static int safe_isspace(char c){
+  return (c&0x80)==0 ? isspace(c) : 0;
+}
+static int safe_tolower(char c){
+  return (c&0x80)==0 ? tolower(c) : c;
+}
+static int safe_isalnum(char c){
+  return (c&0x80)==0 ? isalnum(c) : 0;
+}
+
+typedef enum DocListType {
+  DL_DOCIDS,              /* docids only */
+  DL_POSITIONS,           /* docids + positions */
+  DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
+} DocListType;
+
+/*
+** By default, only positions and not offsets are stored in the doclists.
+** To change this so that offsets are stored too, compile with
+**
+**          -DDL_DEFAULT=DL_POSITIONS_OFFSETS
+**
+** If DL_DEFAULT is set to DL_DOCIDS, your table can only be inserted
+** into (no deletes or updates).
+*/
+#ifndef DL_DEFAULT
+# define DL_DEFAULT DL_POSITIONS
+#endif
+
+enum {
+  POS_END = 0,        /* end of this position list */
+  POS_COLUMN,         /* followed by new column number */
+  POS_BASE
+};
+
+/* MERGE_COUNT controls how often we merge segments (see comment at
+** top of file).
+*/
+#define MERGE_COUNT 16
+
+/* utility functions */
+
+/* CLEAR() and SCRAMBLE() abstract memset() on a pointer to a single
+** record to prevent errors of the form:
+**
+** my_function(SomeType *b){
+**   memset(b, '\0', sizeof(b));  // sizeof(b)!=sizeof(*b)
+** }
+*/
+/* TODO(shess) Obvious candidates for a header file. */
+#define CLEAR(b) memset(b, '\0', sizeof(*(b)))
+
+#ifndef NDEBUG
+#  define SCRAMBLE(b) memset(b, 0x55, sizeof(*(b)))
 #else
-          switch( *zSql ){
-            case 'c': case 'C': {
-              if( nId==6 && sqlite3StrNICmp(zSql, "create", 6)==0 ){
-                token = tkCREATE;
-              }else{
-                token = tkOTHER;
-              }
-              break;
-            }
-            case 't': case 'T': {
-              if( nId==7 && sqlite3StrNICmp(zSql, "trigger", 7)==0 ){
-                token = tkTRIGGER;
-              }else if( nId==4 && sqlite3StrNICmp(zSql, "temp", 4)==0 ){
-                token = tkTEMP;
-              }else if( nId==9 && sqlite3StrNICmp(zSql, "temporary", 9)==0 ){
-                token = tkTEMP;
-              }else{
-                token = tkOTHER;
-              }
-              break;
-            }
-            case 'e':  case 'E': {
-              if( nId==3 && sqlite3StrNICmp(zSql, "end", 3)==0 ){
-                token = tkEND;
-              }else
-#ifndef SQLITE_OMIT_EXPLAIN
-              if( nId==7 && sqlite3StrNICmp(zSql, "explain", 7)==0 ){
-                token = tkEXPLAIN;
-              }else
+#  define SCRAMBLE(b)
 #endif
-              {
-                token = tkOTHER;
-              }
-              break;
-            }
-            default: {
-              token = tkOTHER;
-              break;
-            }
-          }
-#endif /* SQLITE_OMIT_TRIGGER */
-          zSql += nId-1;
-        }else{
-          /* Operators and special symbols */
-          token = tkOTHER;
-        }
-        break;
-      }
+
+/* We may need up to VARINT_MAX bytes to store an encoded 64-bit integer. */
+#define VARINT_MAX 10
+
+/* Write a 64-bit variable-length integer to memory starting at p[0].
+ * The length of data written will be between 1 and VARINT_MAX bytes.
+ * The number of bytes written is returned. */
+static int fts3PutVarint(char *p, sqlite_int64 v){
+  unsigned char *q = (unsigned char *) p;
+  sqlite_uint64 vu = v;
+  do{
+    *q++ = (unsigned char) ((vu & 0x7f) | 0x80);
+    vu >>= 7;
+  }while( vu!=0 );
+  q[-1] &= 0x7f;  /* turn off high bit in final byte */
+  assert( q - (unsigned char *)p <= VARINT_MAX );
+  return (int) (q - (unsigned char *)p);
+}
+
+/* Read a 64-bit variable-length integer from memory starting at p[0].
+ * Return the number of bytes read, or 0 on error.
+ * The value is stored in *v. */
+static int fts3GetVarint(const char *p, sqlite_int64 *v){
+  const unsigned char *q = (const unsigned char *) p;
+  sqlite_uint64 x = 0, y = 1;
+  while( (*q & 0x80) == 0x80 ){
+    x += y * (*q++ & 0x7f);
+    y <<= 7;
+    if( q - (unsigned char *)p >= VARINT_MAX ){  /* bad data */
+      assert( 0 );
+      return 0;
     }
-    state = trans[state][token];
-    zSql++;
   }
-  return state==0;
+  x += y * (*q++);
+  *v = (sqlite_int64) x;
+  return (int) (q - (unsigned char *)p);
+}
+
+static int fts3GetVarint32(const char *p, int *pi){
+ sqlite_int64 i;
+ int ret = fts3GetVarint(p, &i);
+ *pi = (int) i;
+ assert( *pi==i );
+ return ret;
 }
 
-#ifndef SQLITE_OMIT_UTF16
-/*
-** This routine is the same as the sqlite3_complete() routine described
-** above, except that the parameter is required to be UTF-16 encoded, not
-** UTF-8.
+/*******************************************************************/
+/* DataBuffer is used to collect data into a buffer in piecemeal
+** fashion.  It implements the usual distinction between amount of
+** data currently stored (nData) and buffer capacity (nCapacity).
+**
+** dataBufferInit - create a buffer with given initial capacity.
+** dataBufferReset - forget buffer's data, retaining capacity.
+** dataBufferDestroy - free buffer's data.
+** dataBufferSwap - swap contents of two buffers.
+** dataBufferExpand - expand capacity without adding data.
+** dataBufferAppend - append data.
+** dataBufferAppend2 - append two pieces of data at once.
+** dataBufferReplace - replace buffer's data.
 */
-SQLITE_API int sqlite3_complete16(const void *zSql){
-  sqlite3_value *pVal;
-  char const *zSql8;
-  int rc = SQLITE_NOMEM;
+typedef struct DataBuffer {
+  char *pData;          /* Pointer to malloc'ed buffer. */
+  int nCapacity;        /* Size of pData buffer. */
+  int nData;            /* End of data loaded into pData. */
+} DataBuffer;
 
-  pVal = sqlite3ValueNew(0);
-  sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC);
-  zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8);
-  if( zSql8 ){
-    rc = sqlite3_complete(zSql8);
+static void dataBufferInit(DataBuffer *pBuffer, int nCapacity){
+  assert( nCapacity>=0 );
+  pBuffer->nData = 0;
+  pBuffer->nCapacity = nCapacity;
+  pBuffer->pData = nCapacity==0 ? NULL : sqlite3_malloc(nCapacity);
+}
+static void dataBufferReset(DataBuffer *pBuffer){
+  pBuffer->nData = 0;
+}
+static void dataBufferDestroy(DataBuffer *pBuffer){
+  if( pBuffer->pData!=NULL ) sqlite3_free(pBuffer->pData);
+  SCRAMBLE(pBuffer);
+}
+static void dataBufferSwap(DataBuffer *pBuffer1, DataBuffer *pBuffer2){
+  DataBuffer tmp = *pBuffer1;
+  *pBuffer1 = *pBuffer2;
+  *pBuffer2 = tmp;
+}
+static void dataBufferExpand(DataBuffer *pBuffer, int nAddCapacity){
+  assert( nAddCapacity>0 );
+  /* TODO(shess) Consider expanding more aggressively.  Note that the
+  ** underlying malloc implementation may take care of such things for
+  ** us already.
+  */
+  if( pBuffer->nData+nAddCapacity>pBuffer->nCapacity ){
+    pBuffer->nCapacity = pBuffer->nData+nAddCapacity;
+    pBuffer->pData = sqlite3_realloc(pBuffer->pData, pBuffer->nCapacity);
   }
-  sqlite3ValueFree(pVal);
-  return sqlite3ApiExit(0, rc);
 }
-#endif /* SQLITE_OMIT_UTF16 */
-#endif /* SQLITE_OMIT_COMPLETE */
+static void dataBufferAppend(DataBuffer *pBuffer,
+                             const char *pSource, int nSource){
+  assert( nSource>0 && pSource!=NULL );
+  dataBufferExpand(pBuffer, nSource);
+  memcpy(pBuffer->pData+pBuffer->nData, pSource, nSource);
+  pBuffer->nData += nSource;
+}
+static void dataBufferAppend2(DataBuffer *pBuffer,
+                              const char *pSource1, int nSource1,
+                              const char *pSource2, int nSource2){
+  assert( nSource1>0 && pSource1!=NULL );
+  assert( nSource2>0 && pSource2!=NULL );
+  dataBufferExpand(pBuffer, nSource1+nSource2);
+  memcpy(pBuffer->pData+pBuffer->nData, pSource1, nSource1);
+  memcpy(pBuffer->pData+pBuffer->nData+nSource1, pSource2, nSource2);
+  pBuffer->nData += nSource1+nSource2;
+}
+static void dataBufferReplace(DataBuffer *pBuffer,
+                              const char *pSource, int nSource){
+  dataBufferReset(pBuffer);
+  dataBufferAppend(pBuffer, pSource, nSource);
+}
 
-/************** End of complete.c ********************************************/
-/************** Begin file main.c ********************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** Main file for the SQLite library.  The routines in this file
-** implement the programmer interface to the library.  Routines in
-** other files are for internal use by SQLite and should not be
-** accessed by users of the library.
-**
-** $Id: main.c,v 1.439 2008/05/13 13:27:34 drh Exp $
-*/
-#ifdef SQLITE_ENABLE_FTS3
-/************** Include fts3.h in the middle of main.c ***********************/
-/************** Begin file fts3.h ********************************************/
-/*
-** 2006 Oct 10
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This header file is used by programs that want to link against the
-** FTS3 library.  All it does is declare the sqlite3Fts3Init() interface.
-*/
+/* StringBuffer is a null-terminated version of DataBuffer. */
+typedef struct StringBuffer {
+  DataBuffer b;            /* Includes null terminator. */
+} StringBuffer;
 
-#if 0
-extern "C" {
-#endif  /* __cplusplus */
+static void initStringBuffer(StringBuffer *sb){
+  dataBufferInit(&sb->b, 100);
+  dataBufferReplace(&sb->b, "", 1);
+}
+static int stringBufferLength(StringBuffer *sb){
+  return sb->b.nData-1;
+}
+static char *stringBufferData(StringBuffer *sb){
+  return sb->b.pData;
+}
+static void stringBufferDestroy(StringBuffer *sb){
+  dataBufferDestroy(&sb->b);
+}
 
-SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db);
+static void nappend(StringBuffer *sb, const char *zFrom, int nFrom){
+  assert( sb->b.nData>0 );
+  if( nFrom>0 ){
+    sb->b.nData--;
+    dataBufferAppend2(&sb->b, zFrom, nFrom, "", 1);
+  }
+}
+static void append(StringBuffer *sb, const char *zFrom){
+  nappend(sb, zFrom, strlen(zFrom));
+}
 
-#if 0
-}  /* extern "C" */
-#endif  /* __cplusplus */
+/* Append a list of strings separated by commas. */
+static void appendList(StringBuffer *sb, int nString, char **azString){
+  int i;
+  for(i=0; i<nString; ++i){
+    if( i>0 ) append(sb, ", ");
+    append(sb, azString[i]);
+  }
+}
 
-/************** End of fts3.h ************************************************/
-/************** Continuing where we left off in main.c ***********************/
-#endif
+static int endsInWhiteSpace(StringBuffer *p){
+  return stringBufferLength(p)>0 &&
+    safe_isspace(stringBufferData(p)[stringBufferLength(p)-1]);
+}
 
-/*
-** The version of the library
+/* If the StringBuffer ends in something other than white space, add a
+** single space character to the end.
 */
-SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
-SQLITE_API const char *sqlite3_libversion(void){ return sqlite3_version; }
-SQLITE_API int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
-SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
+static void appendWhiteSpace(StringBuffer *p){
+  if( stringBufferLength(p)==0 ) return;
+  if( !endsInWhiteSpace(p) ) append(p, " ");
+}
 
-#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
-/*
-** If the following function pointer is not NULL and if
-** SQLITE_ENABLE_IOTRACE is enabled, then messages describing
-** I/O active are written using this function.  These messages
-** are intended for debugging activity only.
-*/
-SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*, ...) = 0;
-#endif
+/* Remove white space from the end of the StringBuffer */
+static void trimWhiteSpace(StringBuffer *p){
+  while( endsInWhiteSpace(p) ){
+    p->b.pData[--p->b.nData-1] = '\0';
+  }
+}
 
-/*
-** If the following global variable points to a string which is the
-** name of a directory, then that directory will be used to store
-** temporary files.
+/*******************************************************************/
+/* DLReader is used to read document elements from a doclist.  The
+** current docid is cached, so dlrDocid() is fast.  DLReader does not
+** own the doclist buffer.
 **
-** See also the "PRAGMA temp_store_directory" SQL command.
+** dlrAtEnd - true if there's no more data to read.
+** dlrDocid - docid of current document.
+** dlrDocData - doclist data for current document (including docid).
+** dlrDocDataBytes - length of same.
+** dlrAllDataBytes - length of all remaining data.
+** dlrPosData - position data for current document.
+** dlrPosDataLen - length of pos data for current document (incl POS_END).
+** dlrStep - step to current document.
+** dlrInit - initial for doclist of given type against given data.
+** dlrDestroy - clean up.
+**
+** Expected usage is something like:
+**
+**   DLReader reader;
+**   dlrInit(&reader, pData, nData);
+**   while( !dlrAtEnd(&reader) ){
+**     // calls to dlrDocid() and kin.
+**     dlrStep(&reader);
+**   }
+**   dlrDestroy(&reader);
 */
-SQLITE_API char *sqlite3_temp_directory = 0;
+typedef struct DLReader {
+  DocListType iType;
+  const char *pData;
+  int nData;
 
-/*
-** Routine needed to support the testcase() macro.
+  sqlite_int64 iDocid;
+  int nElement;
+} DLReader;
+
+static int dlrAtEnd(DLReader *pReader){
+  assert( pReader->nData>=0 );
+  return pReader->nData==0;
+}
+static sqlite_int64 dlrDocid(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->iDocid;
+}
+static const char *dlrDocData(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->pData;
+}
+static int dlrDocDataBytes(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nElement;
+}
+static int dlrAllDataBytes(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nData;
+}
+/* TODO(shess) Consider adding a field to track iDocid varint length
+** to make these two functions faster.  This might matter (a tiny bit)
+** for queries.
 */
-#ifdef SQLITE_COVERAGE_TEST
-SQLITE_PRIVATE void sqlite3Coverage(int x){
-  static int dummy = 0;
-  dummy += x;
+static const char *dlrPosData(DLReader *pReader){
+  sqlite_int64 iDummy;
+  int n = fts3GetVarint(pReader->pData, &iDummy);
+  assert( !dlrAtEnd(pReader) );
+  return pReader->pData+n;
 }
-#endif
+static int dlrPosDataLen(DLReader *pReader){
+  sqlite_int64 iDummy;
+  int n = fts3GetVarint(pReader->pData, &iDummy);
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nElement-n;
+}
+static void dlrStep(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
 
+  /* Skip past current doclist element. */
+  assert( pReader->nElement<=pReader->nData );
+  pReader->pData += pReader->nElement;
+  pReader->nData -= pReader->nElement;
 
-/*
-** Return true if the buffer z[0..n-1] contains all spaces.
-*/
-static int allSpaces(const char *z, int n){
-  while( n>0 && z[n-1]==' ' ){ n--; }
-  return n==0;
+  /* If there is more data, read the next doclist element. */
+  if( pReader->nData!=0 ){
+    sqlite_int64 iDocidDelta;
+    int iDummy, n = fts3GetVarint(pReader->pData, &iDocidDelta);
+    pReader->iDocid += iDocidDelta;
+    if( pReader->iType>=DL_POSITIONS ){
+      assert( n<pReader->nData );
+      while( 1 ){
+        n += fts3GetVarint32(pReader->pData+n, &iDummy);
+        assert( n<=pReader->nData );
+        if( iDummy==POS_END ) break;
+        if( iDummy==POS_COLUMN ){
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          assert( n<pReader->nData );
+        }else if( pReader->iType==DL_POSITIONS_OFFSETS ){
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          assert( n<pReader->nData );
+        }
+      }
+    }
+    pReader->nElement = n;
+    assert( pReader->nElement<=pReader->nData );
+  }
+}
+static void dlrInit(DLReader *pReader, DocListType iType,
+                    const char *pData, int nData){
+  assert( pData!=NULL && nData!=0 );
+  pReader->iType = iType;
+  pReader->pData = pData;
+  pReader->nData = nData;
+  pReader->nElement = 0;
+  pReader->iDocid = 0;
+
+  /* Load the first element's data.  There must be a first element. */
+  dlrStep(pReader);
+}
+static void dlrDestroy(DLReader *pReader){
+  SCRAMBLE(pReader);
 }
 
-/*
-** This is the default collating function named "BINARY" which is always
-** available.
-**
-** If the padFlag argument is not NULL then space padding at the end
-** of strings is ignored.  This implements the RTRIM collation.
+#ifndef NDEBUG
+/* Verify that the doclist can be validly decoded.  Also returns the
+** last docid found because it is convenient in other assertions for
+** DLWriter.
 */
-static int binCollFunc(
-  void *padFlag,
-  int nKey1, const void *pKey1,
-  int nKey2, const void *pKey2
-){
-  int rc, n;
-  n = nKey1<nKey2 ? nKey1 : nKey2;
-  rc = memcmp(pKey1, pKey2, n);
-  if( rc==0 ){
-    if( padFlag
-     && allSpaces(((char*)pKey1)+n, nKey1-n)
-     && allSpaces(((char*)pKey2)+n, nKey2-n)
-    ){
-      /* Leave rc unchanged at 0 */
-    }else{
-      rc = nKey1 - nKey2;
+static void docListValidate(DocListType iType, const char *pData, int nData,
+                            sqlite_int64 *pLastDocid){
+  sqlite_int64 iPrevDocid = 0;
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
+  while( nData!=0 ){
+    sqlite_int64 iDocidDelta;
+    int n = fts3GetVarint(pData, &iDocidDelta);
+    iPrevDocid += iDocidDelta;
+    if( iType>DL_DOCIDS ){
+      int iDummy;
+      while( 1 ){
+        n += fts3GetVarint32(pData+n, &iDummy);
+        if( iDummy==POS_END ) break;
+        if( iDummy==POS_COLUMN ){
+          n += fts3GetVarint32(pData+n, &iDummy);
+        }else if( iType>DL_POSITIONS ){
+          n += fts3GetVarint32(pData+n, &iDummy);
+          n += fts3GetVarint32(pData+n, &iDummy);
+        }
+        assert( n<=nData );
+      }
     }
+    assert( n<=nData );
+    pData += n;
+    nData -= n;
   }
-  return rc;
+  if( pLastDocid ) *pLastDocid = iPrevDocid;
 }
+#define ASSERT_VALID_DOCLIST(i, p, n, o) docListValidate(i, p, n, o)
+#else
+#define ASSERT_VALID_DOCLIST(i, p, n, o) assert( 1 )
+#endif
 
-/*
-** Another built-in collating sequence: NOCASE. 
+/*******************************************************************/
+/* DLWriter is used to write doclist data to a DataBuffer.  DLWriter
+** always appends to the buffer and does not own it.
 **
-** This collating sequence is intended to be used for "case independant
-** comparison". SQLite's knowledge of upper and lower case equivalents
-** extends only to the 26 characters used in the English language.
+** dlwInit - initialize to write a given type doclistto a buffer.
+** dlwDestroy - clear the writer's memory.  Does not free buffer.
+** dlwAppend - append raw doclist data to buffer.
+** dlwCopy - copy next doclist from reader to writer.
+** dlwAdd - construct doclist element and append to buffer.
+**    Only apply dlwAdd() to DL_DOCIDS doclists (else use PLWriter).
+*/
+typedef struct DLWriter {
+  DocListType iType;
+  DataBuffer *b;
+  sqlite_int64 iPrevDocid;
+#ifndef NDEBUG
+  int has_iPrevDocid;
+#endif
+} DLWriter;
+
+static void dlwInit(DLWriter *pWriter, DocListType iType, DataBuffer *b){
+  pWriter->b = b;
+  pWriter->iType = iType;
+  pWriter->iPrevDocid = 0;
+#ifndef NDEBUG
+  pWriter->has_iPrevDocid = 0;
+#endif
+}
+static void dlwDestroy(DLWriter *pWriter){
+  SCRAMBLE(pWriter);
+}
+/* iFirstDocid is the first docid in the doclist in pData.  It is
+** needed because pData may point within a larger doclist, in which
+** case the first item would be delta-encoded.
 **
-** At the moment there is only a UTF-8 implementation.
+** iLastDocid is the final docid in the doclist in pData.  It is
+** needed to create the new iPrevDocid for future delta-encoding.  The
+** code could decode the passed doclist to recreate iLastDocid, but
+** the only current user (docListMerge) already has decoded this
+** information.
 */
-static int nocaseCollatingFunc(
-  void *NotUsed,
-  int nKey1, const void *pKey1,
-  int nKey2, const void *pKey2
-){
-  int r = sqlite3StrNICmp(
-      (const char *)pKey1, (const char *)pKey2, (nKey1<nKey2)?nKey1:nKey2);
-  if( 0==r ){
-    r = nKey1-nKey2;
+/* TODO(shess) This has become just a helper for docListMerge.
+** Consider a refactor to make this cleaner.
+*/
+static void dlwAppend(DLWriter *pWriter,
+                      const char *pData, int nData,
+                      sqlite_int64 iFirstDocid, sqlite_int64 iLastDocid){
+  sqlite_int64 iDocid = 0;
+  char c[VARINT_MAX];
+  int nFirstOld, nFirstNew;     /* Old and new varint len of first docid. */
+#ifndef NDEBUG
+  sqlite_int64 iLastDocidDelta;
+#endif
+
+  /* Recode the initial docid as delta from iPrevDocid. */
+  nFirstOld = fts3GetVarint(pData, &iDocid);
+  assert( nFirstOld<nData || (nFirstOld==nData && pWriter->iType==DL_DOCIDS) );
+  nFirstNew = fts3PutVarint(c, iFirstDocid-pWriter->iPrevDocid);
+
+  /* Verify that the incoming doclist is valid AND that it ends with
+  ** the expected docid.  This is essential because we'll trust this
+  ** docid in future delta-encoding.
+  */
+  ASSERT_VALID_DOCLIST(pWriter->iType, pData, nData, &iLastDocidDelta);
+  assert( iLastDocid==iFirstDocid-iDocid+iLastDocidDelta );
+
+  /* Append recoded initial docid and everything else.  Rest of docids
+  ** should have been delta-encoded from previous initial docid.
+  */
+  if( nFirstOld<nData ){
+    dataBufferAppend2(pWriter->b, c, nFirstNew,
+                      pData+nFirstOld, nData-nFirstOld);
+  }else{
+    dataBufferAppend(pWriter->b, c, nFirstNew);
   }
-  return r;
+  pWriter->iPrevDocid = iLastDocid;
+}
+static void dlwCopy(DLWriter *pWriter, DLReader *pReader){
+  dlwAppend(pWriter, dlrDocData(pReader), dlrDocDataBytes(pReader),
+            dlrDocid(pReader), dlrDocid(pReader));
+}
+static void dlwAdd(DLWriter *pWriter, sqlite_int64 iDocid){
+  char c[VARINT_MAX];
+  int n = fts3PutVarint(c, iDocid-pWriter->iPrevDocid);
+
+  /* Docids must ascend. */
+  assert( !pWriter->has_iPrevDocid || iDocid>pWriter->iPrevDocid );
+  assert( pWriter->iType==DL_DOCIDS );
+
+  dataBufferAppend(pWriter->b, c, n);
+  pWriter->iPrevDocid = iDocid;
+#ifndef NDEBUG
+  pWriter->has_iPrevDocid = 1;
+#endif
 }
 
-/*
-** Return the ROWID of the most recent insert
-*/
-SQLITE_API sqlite_int64 sqlite3_last_insert_rowid(sqlite3 *db){
-  return db->lastRowid;
-}
+/*******************************************************************/
+/* PLReader is used to read data from a document's position list.  As
+** the caller steps through the list, data is cached so that varints
+** only need to be decoded once.
+**
+** plrInit, plrDestroy - create/destroy a reader.
+** plrColumn, plrPosition, plrStartOffset, plrEndOffset - accessors
+** plrAtEnd - at end of stream, only call plrDestroy once true.
+** plrStep - step to the next element.
+*/
+typedef struct PLReader {
+  /* These refer to the next position's data.  nData will reach 0 when
+  ** reading the last position, so plrStep() signals EOF by setting
+  ** pData to NULL.
+  */
+  const char *pData;
+  int nData;
+
+  DocListType iType;
+  int iColumn;         /* the last column read */
+  int iPosition;       /* the last position read */
+  int iStartOffset;    /* the last start offset read */
+  int iEndOffset;      /* the last end offset read */
+} PLReader;
 
-/*
-** Return the number of changes in the most recent call to sqlite3_exec().
-*/
-SQLITE_API int sqlite3_changes(sqlite3 *db){
-  return db->nChange;
+static int plrAtEnd(PLReader *pReader){
+  return pReader->pData==NULL;
 }
-
-/*
-** Return the number of changes since the database handle was opened.
-*/
-SQLITE_API int sqlite3_total_changes(sqlite3 *db){
-  return db->nTotalChange;
+static int plrColumn(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iColumn;
+}
+static int plrPosition(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iPosition;
+}
+static int plrStartOffset(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iStartOffset;
+}
+static int plrEndOffset(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iEndOffset;
 }
+static void plrStep(PLReader *pReader){
+  int i, n;
 
-/*
-** Close an existing SQLite database
-*/
-SQLITE_API int sqlite3_close(sqlite3 *db){
-  HashElem *i;
-  int j;
+  assert( !plrAtEnd(pReader) );
 
-  if( !db ){
-    return SQLITE_OK;
-  }
-  if( !sqlite3SafetyCheckSickOrOk(db) ){
-    return SQLITE_MISUSE;
+  if( pReader->nData==0 ){
+    pReader->pData = NULL;
+    return;
   }
-  sqlite3_mutex_enter(db->mutex);
 
-#ifdef SQLITE_SSE
-  {
-    extern void sqlite3SseCleanup(sqlite3*);
-    sqlite3SseCleanup(db);
+  n = fts3GetVarint32(pReader->pData, &i);
+  if( i==POS_COLUMN ){
+    n += fts3GetVarint32(pReader->pData+n, &pReader->iColumn);
+    pReader->iPosition = 0;
+    pReader->iStartOffset = 0;
+    n += fts3GetVarint32(pReader->pData+n, &i);
   }
-#endif 
-
-  sqlite3ResetInternalSchema(db, 0);
-
-  /* If a transaction is open, the ResetInternalSchema() call above
-  ** will not have called the xDisconnect() method on any virtual
-  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
-  ** call will do so. We need to do this before the check for active
-  ** SQL statements below, as the v-table implementation may be storing
-  ** some prepared statements internally.
-  */
-  sqlite3VtabRollback(db);
+  /* Should never see adjacent column changes. */
+  assert( i!=POS_COLUMN );
 
-  /* If there are any outstanding VMs, return SQLITE_BUSY. */
-  if( db->pVdbe ){
-    sqlite3Error(db, SQLITE_BUSY, 
-        "Unable to close due to unfinalised statements");
-    sqlite3_mutex_leave(db->mutex);
-    return SQLITE_BUSY;
+  if( i==POS_END ){
+    pReader->nData = 0;
+    pReader->pData = NULL;
+    return;
   }
-  assert( sqlite3SafetyCheckSickOrOk(db) );
 
-  for(j=0; j<db->nDb; j++){
-    struct Db *pDb = &db->aDb[j];
-    if( pDb->pBt ){
-      sqlite3BtreeClose(pDb->pBt);
-      pDb->pBt = 0;
-      if( j!=1 ){
-        pDb->pSchema = 0;
-      }
-    }
-  }
-  sqlite3ResetInternalSchema(db, 0);
-  assert( db->nDb<=2 );
-  assert( db->aDb==db->aDbStatic );
-  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
-    FuncDef *pFunc, *pNext;
-    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
-      pNext = pFunc->pNext;
-      sqlite3_free(pFunc);
-    }
+  pReader->iPosition += i-POS_BASE;
+  if( pReader->iType==DL_POSITIONS_OFFSETS ){
+    n += fts3GetVarint32(pReader->pData+n, &i);
+    pReader->iStartOffset += i;
+    n += fts3GetVarint32(pReader->pData+n, &i);
+    pReader->iEndOffset = pReader->iStartOffset+i;
   }
+  assert( n<=pReader->nData );
+  pReader->pData += n;
+  pReader->nData -= n;
+}
 
-  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
-    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
-    /* Invoke any destructors registered for collation sequence user data. */
-    for(j=0; j<3; j++){
-      if( pColl[j].xDel ){
-        pColl[j].xDel(pColl[j].pUser);
-      }
-    }
-    sqlite3_free(pColl);
-  }
-  sqlite3HashClear(&db->aCollSeq);
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
-    Module *pMod = (Module *)sqliteHashData(i);
-    if( pMod->xDestroy ){
-      pMod->xDestroy(pMod->pAux);
-    }
-    sqlite3_free(pMod);
-  }
-  sqlite3HashClear(&db->aModule);
-#endif
+static void plrInit(PLReader *pReader, DLReader *pDLReader){
+  pReader->pData = dlrPosData(pDLReader);
+  pReader->nData = dlrPosDataLen(pDLReader);
+  pReader->iType = pDLReader->iType;
+  pReader->iColumn = 0;
+  pReader->iPosition = 0;
+  pReader->iStartOffset = 0;
+  pReader->iEndOffset = 0;
+  plrStep(pReader);
+}
+static void plrDestroy(PLReader *pReader){
+  SCRAMBLE(pReader);
+}
 
-  sqlite3HashClear(&db->aFunc);
-  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
-  if( db->pErr ){
-    sqlite3ValueFree(db->pErr);
-  }
-  sqlite3CloseExtensions(db);
+/*******************************************************************/
+/* PLWriter is used in constructing a document's position list.  As a
+** convenience, if iType is DL_DOCIDS, PLWriter becomes a no-op.
+** PLWriter writes to the associated DLWriter's buffer.
+**
+** plwInit - init for writing a document's poslist.
+** plwDestroy - clear a writer.
+** plwAdd - append position and offset information.
+** plwCopy - copy next position's data from reader to writer.
+** plwTerminate - add any necessary doclist terminator.
+**
+** Calling plwAdd() after plwTerminate() may result in a corrupt
+** doclist.
+*/
+/* TODO(shess) Until we've written the second item, we can cache the
+** first item's information.  Then we'd have three states:
+**
+** - initialized with docid, no positions.
+** - docid and one position.
+** - docid and multiple positions.
+**
+** Only the last state needs to actually write to dlw->b, which would
+** be an improvement in the DLCollector case.
+*/
+typedef struct PLWriter {
+  DLWriter *dlw;
 
-  db->magic = SQLITE_MAGIC_ERROR;
+  int iColumn;    /* the last column written */
+  int iPos;       /* the last position written */
+  int iOffset;    /* the last start offset written */
+} PLWriter;
 
-  /* The temp-database schema is allocated differently from the other schema
-  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
-  ** So it needs to be freed here. Todo: Why not roll the temp schema into
-  ** the same sqliteMalloc() as the one that allocates the database 
-  ** structure?
+/* TODO(shess) In the case where the parent is reading these values
+** from a PLReader, we could optimize to a copy if that PLReader has
+** the same type as pWriter.
+*/
+static void plwAdd(PLWriter *pWriter, int iColumn, int iPos,
+                   int iStartOffset, int iEndOffset){
+  /* Worst-case space for POS_COLUMN, iColumn, iPosDelta,
+  ** iStartOffsetDelta, and iEndOffsetDelta.
   */
-  sqlite3_free(db->aDb[1].pSchema);
-  sqlite3_mutex_leave(db->mutex);
-  db->magic = SQLITE_MAGIC_CLOSED;
-  sqlite3_mutex_free(db->mutex);
-  sqlite3_free(db);
-  return SQLITE_OK;
-}
+  char c[5*VARINT_MAX];
+  int n = 0;
 
-/*
-** Rollback all database files.
-*/
-SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db){
-  int i;
-  int inTrans = 0;
-  assert( sqlite3_mutex_held(db->mutex) );
-  sqlite3FaultBeginBenign(SQLITE_FAULTINJECTOR_MALLOC);
-  for(i=0; i<db->nDb; i++){
-    if( db->aDb[i].pBt ){
-      if( sqlite3BtreeIsInTrans(db->aDb[i].pBt) ){
-        inTrans = 1;
-      }
-      sqlite3BtreeRollback(db->aDb[i].pBt);
-      db->aDb[i].inTrans = 0;
-    }
-  }
-  sqlite3VtabRollback(db);
-  sqlite3FaultEndBenign(SQLITE_FAULTINJECTOR_MALLOC);
+  /* Ban plwAdd() after plwTerminate(). */
+  assert( pWriter->iPos!=-1 );
 
-  if( db->flags&SQLITE_InternChanges ){
-    sqlite3ExpirePreparedStatements(db);
-    sqlite3ResetInternalSchema(db, 0);
-  }
+  if( pWriter->dlw->iType==DL_DOCIDS ) return;
 
-  /* If one has been configured, invoke the rollback-hook callback */
-  if( db->xRollbackCallback && (inTrans || !db->autoCommit) ){
-    db->xRollbackCallback(db->pRollbackArg);
+  if( iColumn!=pWriter->iColumn ){
+    n += fts3PutVarint(c+n, POS_COLUMN);
+    n += fts3PutVarint(c+n, iColumn);
+    pWriter->iColumn = iColumn;
+    pWriter->iPos = 0;
+    pWriter->iOffset = 0;
   }
-}
-
-/*
-** Return a static string that describes the kind of error specified in the
-** argument.
-*/
-SQLITE_PRIVATE const char *sqlite3ErrStr(int rc){
-  const char *z;
-  switch( rc & 0xff ){
-    case SQLITE_ROW:
-    case SQLITE_DONE:
-    case SQLITE_OK:         z = "not an error";                          break;
-    case SQLITE_ERROR:      z = "SQL logic error or missing database";   break;
-    case SQLITE_PERM:       z = "access permission denied";              break;
-    case SQLITE_ABORT:      z = "callback requested query abort";        break;
-    case SQLITE_BUSY:       z = "database is locked";                    break;
-    case SQLITE_LOCKED:     z = "database table is locked";              break;
-    case SQLITE_NOMEM:      z = "out of memory";                         break;
-    case SQLITE_READONLY:   z = "attempt to write a readonly database";  break;
-    case SQLITE_INTERRUPT:  z = "interrupted";                           break;
-    case SQLITE_IOERR:      z = "disk I/O error";                        break;
-    case SQLITE_CORRUPT:    z = "database disk image is malformed";      break;
-    case SQLITE_FULL:       z = "database or disk is full";              break;
-    case SQLITE_CANTOPEN:   z = "unable to open database file";          break;
-    case SQLITE_EMPTY:      z = "table contains no data";                break;
-    case SQLITE_SCHEMA:     z = "database schema has changed";           break;
-    case SQLITE_TOOBIG:     z = "String or BLOB exceeded size limit";    break;
-    case SQLITE_CONSTRAINT: z = "constraint failed";                     break;
-    case SQLITE_MISMATCH:   z = "datatype mismatch";                     break;
-    case SQLITE_MISUSE:     z = "library routine called out of sequence";break;
-    case SQLITE_NOLFS:      z = "large file support is disabled";        break;
-    case SQLITE_AUTH:       z = "authorization denied";                  break;
-    case SQLITE_FORMAT:     z = "auxiliary database format error";       break;
-    case SQLITE_RANGE:      z = "bind or column index out of range";     break;
-    case SQLITE_NOTADB:     z = "file is encrypted or is not a database";break;
-    default:                z = "unknown error";                         break;
+  assert( iPos>=pWriter->iPos );
+  n += fts3PutVarint(c+n, POS_BASE+(iPos-pWriter->iPos));
+  pWriter->iPos = iPos;
+  if( pWriter->dlw->iType==DL_POSITIONS_OFFSETS ){
+    assert( iStartOffset>=pWriter->iOffset );
+    n += fts3PutVarint(c+n, iStartOffset-pWriter->iOffset);
+    pWriter->iOffset = iStartOffset;
+    assert( iEndOffset>=iStartOffset );
+    n += fts3PutVarint(c+n, iEndOffset-iStartOffset);
   }
-  return z;
+  dataBufferAppend(pWriter->dlw->b, c, n);
 }
+static void plwCopy(PLWriter *pWriter, PLReader *pReader){
+  plwAdd(pWriter, plrColumn(pReader), plrPosition(pReader),
+         plrStartOffset(pReader), plrEndOffset(pReader));
+}
+static void plwInit(PLWriter *pWriter, DLWriter *dlw, sqlite_int64 iDocid){
+  char c[VARINT_MAX];
+  int n;
 
-/*
-** This routine implements a busy callback that sleeps and tries
-** again until a timeout value is reached.  The timeout value is
-** an integer number of milliseconds passed in as the first
-** argument.
-*/
-static int sqliteDefaultBusyCallback(
- void *ptr,               /* Database connection */
- int count                /* Number of times table has been busy */
-){
-#if OS_WIN || (defined(HAVE_USLEEP) && HAVE_USLEEP)
-  static const u8 delays[] =
-     { 1, 2, 5, 10, 15, 20, 25, 25,  25,  50,  50, 100 };
-  static const u8 totals[] =
-     { 0, 1, 3,  8, 18, 33, 53, 78, 103, 128, 178, 228 };
-# define NDELAY (sizeof(delays)/sizeof(delays[0]))
-  sqlite3 *db = (sqlite3 *)ptr;
-  int timeout = db->busyTimeout;
-  int delay, prior;
+  pWriter->dlw = dlw;
 
-  assert( count>=0 );
-  if( count < NDELAY ){
-    delay = delays[count];
-    prior = totals[count];
-  }else{
-    delay = delays[NDELAY-1];
-    prior = totals[NDELAY-1] + delay*(count-(NDELAY-1));
-  }
-  if( prior + delay > timeout ){
-    delay = timeout - prior;
-    if( delay<=0 ) return 0;
-  }
-  sqlite3OsSleep(db->pVfs, delay*1000);
-  return 1;
-#else
-  sqlite3 *db = (sqlite3 *)ptr;
-  int timeout = ((sqlite3 *)ptr)->busyTimeout;
-  if( (count+1)*1000 > timeout ){
-    return 0;
+  /* Docids must ascend. */
+  assert( !pWriter->dlw->has_iPrevDocid || iDocid>pWriter->dlw->iPrevDocid );
+  n = fts3PutVarint(c, iDocid-pWriter->dlw->iPrevDocid);
+  dataBufferAppend(pWriter->dlw->b, c, n);
+  pWriter->dlw->iPrevDocid = iDocid;
+#ifndef NDEBUG
+  pWriter->dlw->has_iPrevDocid = 1;
+#endif
+
+  pWriter->iColumn = 0;
+  pWriter->iPos = 0;
+  pWriter->iOffset = 0;
+}
+/* TODO(shess) Should plwDestroy() also terminate the doclist?  But
+** then plwDestroy() would no longer be just a destructor, it would
+** also be doing work, which isn't consistent with the overall idiom.
+** Another option would be for plwAdd() to always append any necessary
+** terminator, so that the output is always correct.  But that would
+** add incremental work to the common case with the only benefit being
+** API elegance.  Punt for now.
+*/
+static void plwTerminate(PLWriter *pWriter){
+  if( pWriter->dlw->iType>DL_DOCIDS ){
+    char c[VARINT_MAX];
+    int n = fts3PutVarint(c, POS_END);
+    dataBufferAppend(pWriter->dlw->b, c, n);
   }
-  sqlite3OsSleep(db->pVfs, 1000000);
-  return 1;
+#ifndef NDEBUG
+  /* Mark as terminated for assert in plwAdd(). */
+  pWriter->iPos = -1;
 #endif
 }
+static void plwDestroy(PLWriter *pWriter){
+  SCRAMBLE(pWriter);
+}
 
-/*
-** Invoke the given busy handler.
+/*******************************************************************/
+/* DLCollector wraps PLWriter and DLWriter to provide a
+** dynamically-allocated doclist area to use during tokenization.
 **
-** This routine is called when an operation failed with a lock.
-** If this routine returns non-zero, the lock is retried.  If it
-** returns 0, the operation aborts with an SQLITE_BUSY error.
+** dlcNew - malloc up and initialize a collector.
+** dlcDelete - destroy a collector and all contained items.
+** dlcAddPos - append position and offset information.
+** dlcAddDoclist - add the collected doclist to the given buffer.
+** dlcNext - terminate the current document and open another.
 */
-SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler *p){
-  int rc;
-  if( p==0 || p->xFunc==0 || p->nBusy<0 ) return 0;
-  rc = p->xFunc(p->pArg, p->nBusy);
-  if( rc==0 ){
-    p->nBusy = -1;
+typedef struct DLCollector {
+  DataBuffer b;
+  DLWriter dlw;
+  PLWriter plw;
+} DLCollector;
+
+/* TODO(shess) This could also be done by calling plwTerminate() and
+** dataBufferAppend().  I tried that, expecting nominal performance
+** differences, but it seemed to pretty reliably be worth 1% to code
+** it this way.  I suspect it is the incremental malloc overhead (some
+** percentage of the plwTerminate() calls will cause a realloc), so
+** this might be worth revisiting if the DataBuffer implementation
+** changes.
+*/
+static void dlcAddDoclist(DLCollector *pCollector, DataBuffer *b){
+  if( pCollector->dlw.iType>DL_DOCIDS ){
+    char c[VARINT_MAX];
+    int n = fts3PutVarint(c, POS_END);
+    dataBufferAppend2(b, pCollector->b.pData, pCollector->b.nData, c, n);
   }else{
-    p->nBusy++;
+    dataBufferAppend(b, pCollector->b.pData, pCollector->b.nData);
   }
-  return rc; 
+}
+static void dlcNext(DLCollector *pCollector, sqlite_int64 iDocid){
+  plwTerminate(&pCollector->plw);
+  plwDestroy(&pCollector->plw);
+  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
+}
+static void dlcAddPos(DLCollector *pCollector, int iColumn, int iPos,
+                      int iStartOffset, int iEndOffset){
+  plwAdd(&pCollector->plw, iColumn, iPos, iStartOffset, iEndOffset);
 }
 
-/*
-** This routine sets the busy callback for an Sqlite database to the
-** given callback function with the given argument.
-*/
-SQLITE_API int sqlite3_busy_handler(
-  sqlite3 *db,
-  int (*xBusy)(void*,int),
-  void *pArg
-){
-  sqlite3_mutex_enter(db->mutex);
-  db->busyHandler.xFunc = xBusy;
-  db->busyHandler.pArg = pArg;
-  db->busyHandler.nBusy = 0;
-  sqlite3_mutex_leave(db->mutex);
-  return SQLITE_OK;
+static DLCollector *dlcNew(sqlite_int64 iDocid, DocListType iType){
+  DLCollector *pCollector = sqlite3_malloc(sizeof(DLCollector));
+  dataBufferInit(&pCollector->b, 0);
+  dlwInit(&pCollector->dlw, iType, &pCollector->b);
+  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
+  return pCollector;
+}
+static void dlcDelete(DLCollector *pCollector){
+  plwDestroy(&pCollector->plw);
+  dlwDestroy(&pCollector->dlw);
+  dataBufferDestroy(&pCollector->b);
+  SCRAMBLE(pCollector);
+  sqlite3_free(pCollector);
 }
 
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-/*
-** This routine sets the progress callback for an Sqlite database to the
-** given callback function with the given argument. The progress callback will
-** be invoked every nOps opcodes.
+
+/* Copy the doclist data of iType in pData/nData into *out, trimming
+** unnecessary data as we go.  Only columns matching iColumn are
+** copied, all columns copied if iColumn is -1.  Elements with no
+** matching columns are dropped.  The output is an iOutType doclist.
 */
-SQLITE_API void sqlite3_progress_handler(
-  sqlite3 *db, 
-  int nOps,
-  int (*xProgress)(void*), 
-  void *pArg
-){
-  if( sqlite3SafetyCheckOk(db) ){
-    sqlite3_mutex_enter(db->mutex);
-    if( nOps>0 ){
-      db->xProgress = xProgress;
-      db->nProgressOps = nOps;
-      db->pProgressArg = pArg;
-    }else{
-      db->xProgress = 0;
-      db->nProgressOps = 0;
-      db->pProgressArg = 0;
+/* NOTE(shess) This code is only valid after all doclists are merged.
+** If this is run before merges, then doclist items which represent
+** deletion will be trimmed, and will thus not effect a deletion
+** during the merge.
+*/
+static void docListTrim(DocListType iType, const char *pData, int nData,
+                        int iColumn, DocListType iOutType, DataBuffer *out){
+  DLReader dlReader;
+  DLWriter dlWriter;
+
+  assert( iOutType<=iType );
+
+  dlrInit(&dlReader, iType, pData, nData);
+  dlwInit(&dlWriter, iOutType, out);
+
+  while( !dlrAtEnd(&dlReader) ){
+    PLReader plReader;
+    PLWriter plWriter;
+    int match = 0;
+
+    plrInit(&plReader, &dlReader);
+
+    while( !plrAtEnd(&plReader) ){
+      if( iColumn==-1 || plrColumn(&plReader)==iColumn ){
+        if( !match ){
+          plwInit(&plWriter, &dlWriter, dlrDocid(&dlReader));
+          match = 1;
+        }
+        plwAdd(&plWriter, plrColumn(&plReader), plrPosition(&plReader),
+               plrStartOffset(&plReader), plrEndOffset(&plReader));
+      }
+      plrStep(&plReader);
     }
-    sqlite3_mutex_leave(db->mutex);
+    if( match ){
+      plwTerminate(&plWriter);
+      plwDestroy(&plWriter);
+    }
+
+    plrDestroy(&plReader);
+    dlrStep(&dlReader);
   }
+  dlwDestroy(&dlWriter);
+  dlrDestroy(&dlReader);
 }
-#endif
-
 
-/*
-** This routine installs a default busy handler that waits for the
-** specified number of milliseconds before returning 0.
+/* Used by docListMerge() to keep doclists in the ascending order by
+** docid, then ascending order by age (so the newest comes first).
 */
-SQLITE_API int sqlite3_busy_timeout(sqlite3 *db, int ms){
-  if( ms>0 ){
-    db->busyTimeout = ms;
-    sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)db);
-  }else{
-    sqlite3_busy_handler(db, 0, 0);
+typedef struct OrderedDLReader {
+  DLReader *pReader;
+
+  /* TODO(shess) If we assume that docListMerge pReaders is ordered by
+  ** age (which we do), then we could use pReader comparisons to break
+  ** ties.
+  */
+  int idx;
+} OrderedDLReader;
+
+/* Order eof to end, then by docid asc, idx desc. */
+static int orderedDLReaderCmp(OrderedDLReader *r1, OrderedDLReader *r2){
+  if( dlrAtEnd(r1->pReader) ){
+    if( dlrAtEnd(r2->pReader) ) return 0;  /* Both atEnd(). */
+    return 1;                              /* Only r1 atEnd(). */
   }
-  return SQLITE_OK;
+  if( dlrAtEnd(r2->pReader) ) return -1;   /* Only r2 atEnd(). */
+
+  if( dlrDocid(r1->pReader)<dlrDocid(r2->pReader) ) return -1;
+  if( dlrDocid(r1->pReader)>dlrDocid(r2->pReader) ) return 1;
+
+  /* Descending on idx. */
+  return r2->idx-r1->idx;
 }
 
-/*
-** Cause any pending operation to stop at its earliest opportunity.
+/* Bubble p[0] to appropriate place in p[1..n-1].  Assumes that
+** p[1..n-1] is already sorted.
 */
-SQLITE_API void sqlite3_interrupt(sqlite3 *db){
-  if( sqlite3SafetyCheckOk(db) ){
-    db->u1.isInterrupted = 1;
+/* TODO(shess) Is this frequent enough to warrant a binary search?
+** Before implementing that, instrument the code to check.  In most
+** current usage, I expect that p[0] will be less than p[1] a very
+** high proportion of the time.
+*/
+static void orderedDLReaderReorder(OrderedDLReader *p, int n){
+  while( n>1 && orderedDLReaderCmp(p, p+1)>0 ){
+    OrderedDLReader tmp = p[0];
+    p[0] = p[1];
+    p[1] = tmp;
+    n--;
+    p++;
   }
 }
 
-
-/*
-** This function is exactly the same as sqlite3_create_function(), except
-** that it is designed to be called by internal code. The difference is
-** that if a malloc() fails in sqlite3_create_function(), an error code
-** is returned and the mallocFailed flag cleared. 
+/* Given an array of doclist readers, merge their doclist elements
+** into out in sorted order (by docid), dropping elements from older
+** readers when there is a duplicate docid.  pReaders is assumed to be
+** ordered by age, oldest first.
 */
-SQLITE_PRIVATE int sqlite3CreateFunc(
-  sqlite3 *db,
-  const char *zFunctionName,
-  int nArg,
-  int enc,
-  void *pUserData,
-  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
-  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
-  void (*xFinal)(sqlite3_context*)
-){
-  FuncDef *p;
-  int nName;
+/* TODO(shess) nReaders must be <= MERGE_COUNT.  This should probably
+** be fixed.
+*/
+static void docListMerge(DataBuffer *out,
+                         DLReader *pReaders, int nReaders){
+  OrderedDLReader readers[MERGE_COUNT];
+  DLWriter writer;
+  int i, n;
+  const char *pStart = 0;
+  int nStart = 0;
+  sqlite_int64 iFirstDocid = 0, iLastDocid = 0;
 
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( zFunctionName==0 ||
-      (xFunc && (xFinal || xStep)) || 
-      (!xFunc && (xFinal && !xStep)) ||
-      (!xFunc && (!xFinal && xStep)) ||
-      (nArg<-1 || nArg>127) ||
-      (255<(nName = strlen(zFunctionName))) ){
-    sqlite3Error(db, SQLITE_ERROR, "bad parameters");
-    return SQLITE_ERROR;
+  assert( nReaders>0 );
+  if( nReaders==1 ){
+    dataBufferAppend(out, dlrDocData(pReaders), dlrAllDataBytes(pReaders));
+    return;
   }
-  
-#ifndef SQLITE_OMIT_UTF16
-  /* If SQLITE_UTF16 is specified as the encoding type, transform this
-  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
-  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
-  **
-  ** If SQLITE_ANY is specified, add three versions of the function
-  ** to the hash table.
-  */
-  if( enc==SQLITE_UTF16 ){
-    enc = SQLITE_UTF16NATIVE;
-  }else if( enc==SQLITE_ANY ){
-    int rc;
-    rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF8,
-         pUserData, xFunc, xStep, xFinal);
-    if( rc==SQLITE_OK ){
-      rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF16LE,
-          pUserData, xFunc, xStep, xFinal);
-    }
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    enc = SQLITE_UTF16BE;
+
+  assert( nReaders<=MERGE_COUNT );
+  n = 0;
+  for(i=0; i<nReaders; i++){
+    assert( pReaders[i].iType==pReaders[0].iType );
+    readers[i].pReader = pReaders+i;
+    readers[i].idx = i;
+    n += dlrAllDataBytes(&pReaders[i]);
   }
-#else
-  enc = SQLITE_UTF8;
-#endif
-  
-  /* Check if an existing function is being overridden or deleted. If so,
-  ** and there are active VMs, then return SQLITE_BUSY. If a function
-  ** is being overridden/deleted but there are no active VMs, allow the
-  ** operation to continue but invalidate all precompiled statements.
+  /* Conservatively size output to sum of inputs.  Output should end
+  ** up strictly smaller than input.
   */
-  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 0);
-  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
-    if( db->activeVdbeCnt ){
-      sqlite3Error(db, SQLITE_BUSY, 
-        "Unable to delete/modify user-function due to active statements");
-      assert( !db->mallocFailed );
-      return SQLITE_BUSY;
+  dataBufferExpand(out, n);
+
+  /* Get the readers into sorted order. */
+  while( i-->0 ){
+    orderedDLReaderReorder(readers+i, nReaders-i);
+  }
+
+  dlwInit(&writer, pReaders[0].iType, out);
+  while( !dlrAtEnd(readers[0].pReader) ){
+    sqlite_int64 iDocid = dlrDocid(readers[0].pReader);
+
+    /* If this is a continuation of the current buffer to copy, extend
+    ** that buffer.  memcpy() seems to be more efficient if it has a
+    ** lots of data to copy.
+    */
+    if( dlrDocData(readers[0].pReader)==pStart+nStart ){
+      nStart += dlrDocDataBytes(readers[0].pReader);
     }else{
-      sqlite3ExpirePreparedStatements(db);
+      if( pStart!=0 ){
+        dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
+      }
+      pStart = dlrDocData(readers[0].pReader);
+      nStart = dlrDocDataBytes(readers[0].pReader);
+      iFirstDocid = iDocid;
     }
-  }
+    iLastDocid = iDocid;
+    dlrStep(readers[0].pReader);
 
-  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
-  assert(p || db->mallocFailed);
-  if( !p ){
-    return SQLITE_NOMEM;
+    /* Drop all of the older elements with the same docid. */
+    for(i=1; i<nReaders &&
+             !dlrAtEnd(readers[i].pReader) &&
+             dlrDocid(readers[i].pReader)==iDocid; i++){
+      dlrStep(readers[i].pReader);
+    }
+
+    /* Get the readers back into order. */
+    while( i-->0 ){
+      orderedDLReaderReorder(readers+i, nReaders-i);
+    }
   }
-  p->flags = 0;
-  p->xFunc = xFunc;
-  p->xStep = xStep;
-  p->xFinalize = xFinal;
-  p->pUserData = pUserData;
-  p->nArg = nArg;
-  return SQLITE_OK;
+
+  /* Copy over any remaining elements. */
+  if( nStart>0 ) dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
+  dlwDestroy(&writer);
 }
 
-/*
-** Create new user functions.
+/* Helper function for posListUnion().  Compares the current position
+** between left and right, returning as standard C idiom of <0 if
+** left<right, >0 if left>right, and 0 if left==right.  "End" always
+** compares greater.
 */
-SQLITE_API int sqlite3_create_function(
-  sqlite3 *db,
-  const char *zFunctionName,
-  int nArg,
-  int enc,
-  void *p,
-  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
-  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
-  void (*xFinal)(sqlite3_context*)
-){
-  int rc;
-  sqlite3_mutex_enter(db->mutex);
-  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
+static int posListCmp(PLReader *pLeft, PLReader *pRight){
+  assert( pLeft->iType==pRight->iType );
+  if( pLeft->iType==DL_DOCIDS ) return 0;
 
-#ifndef SQLITE_OMIT_UTF16
-SQLITE_API int sqlite3_create_function16(
-  sqlite3 *db,
-  const void *zFunctionName,
-  int nArg,
-  int eTextRep,
-  void *p,
-  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
-  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
-  void (*xFinal)(sqlite3_context*)
-){
-  int rc;
-  char *zFunc8;
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1);
-  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
-  sqlite3_free(zFunc8);
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
-#endif
+  if( plrAtEnd(pLeft) ) return plrAtEnd(pRight) ? 0 : 1;
+  if( plrAtEnd(pRight) ) return -1;
 
+  if( plrColumn(pLeft)<plrColumn(pRight) ) return -1;
+  if( plrColumn(pLeft)>plrColumn(pRight) ) return 1;
 
-/*
-** Declare that a function has been overloaded by a virtual table.
-**
-** If the function already exists as a regular global function, then
-** this routine is a no-op.  If the function does not exist, then create
-** a new one that always throws a run-time error.  
-**
-** When virtual tables intend to provide an overloaded function, they
-** should call this routine to make sure the global function exists.
-** A global function must exist in order for name resolution to work
-** properly.
-*/
-SQLITE_API int sqlite3_overload_function(
-  sqlite3 *db,
-  const char *zName,
-  int nArg
-){
-  int nName = strlen(zName);
-  int rc;
-  sqlite3_mutex_enter(db->mutex);
-  if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
-    sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
-                      0, sqlite3InvalidFunction, 0, 0);
-  }
-  rc = sqlite3ApiExit(db, SQLITE_OK);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
+  if( plrPosition(pLeft)<plrPosition(pRight) ) return -1;
+  if( plrPosition(pLeft)>plrPosition(pRight) ) return 1;
+  if( pLeft->iType==DL_POSITIONS ) return 0;
 
-#ifndef SQLITE_OMIT_TRACE
-/*
-** Register a trace function.  The pArg from the previously registered trace
-** is returned.  
-**
-** A NULL trace function means that no tracing is executes.  A non-NULL
-** trace is a pointer to a function that is invoked at the start of each
-** SQL statement.
-*/
-SQLITE_API void *sqlite3_trace(sqlite3 *db, void (*xTrace)(void*,const char*), void *pArg){
-  void *pOld;
-  sqlite3_mutex_enter(db->mutex);
-  pOld = db->pTraceArg;
-  db->xTrace = xTrace;
-  db->pTraceArg = pArg;
-  sqlite3_mutex_leave(db->mutex);
-  return pOld;
-}
-/*
-** Register a profile function.  The pArg from the previously registered 
-** profile function is returned.  
-**
-** A NULL profile function means that no profiling is executes.  A non-NULL
-** profile is a pointer to a function that is invoked at the conclusion of
-** each SQL statement that is run.
-*/
-SQLITE_API void *sqlite3_profile(
-  sqlite3 *db,
-  void (*xProfile)(void*,const char*,sqlite_uint64),
-  void *pArg
-){
-  void *pOld;
-  sqlite3_mutex_enter(db->mutex);
-  pOld = db->pProfileArg;
-  db->xProfile = xProfile;
-  db->pProfileArg = pArg;
-  sqlite3_mutex_leave(db->mutex);
-  return pOld;
-}
-#endif /* SQLITE_OMIT_TRACE */
+  if( plrStartOffset(pLeft)<plrStartOffset(pRight) ) return -1;
+  if( plrStartOffset(pLeft)>plrStartOffset(pRight) ) return 1;
 
-/*** EXPERIMENTAL ***
-**
-** Register a function to be invoked when a transaction comments.
-** If the invoked function returns non-zero, then the commit becomes a
-** rollback.
-*/
-SQLITE_API void *sqlite3_commit_hook(
-  sqlite3 *db,              /* Attach the hook to this database */
-  int (*xCallback)(void*),  /* Function to invoke on each commit */
-  void *pArg                /* Argument to the function */
-){
-  void *pOld;
-  sqlite3_mutex_enter(db->mutex);
-  pOld = db->pCommitArg;
-  db->xCommitCallback = xCallback;
-  db->pCommitArg = pArg;
-  sqlite3_mutex_leave(db->mutex);
-  return pOld;
-}
+  if( plrEndOffset(pLeft)<plrEndOffset(pRight) ) return -1;
+  if( plrEndOffset(pLeft)>plrEndOffset(pRight) ) return 1;
 
-/*
-** Register a callback to be invoked each time a row is updated,
-** inserted or deleted using this database connection.
-*/
-SQLITE_API void *sqlite3_update_hook(
-  sqlite3 *db,              /* Attach the hook to this database */
-  void (*xCallback)(void*,int,char const *,char const *,sqlite_int64),
-  void *pArg                /* Argument to the function */
-){
-  void *pRet;
-  sqlite3_mutex_enter(db->mutex);
-  pRet = db->pUpdateArg;
-  db->xUpdateCallback = xCallback;
-  db->pUpdateArg = pArg;
-  sqlite3_mutex_leave(db->mutex);
-  return pRet;
+  return 0;
 }
 
-/*
-** Register a callback to be invoked each time a transaction is rolled
-** back by this database connection.
+/* Write the union of position lists in pLeft and pRight to pOut.
+** "Union" in this case meaning "All unique position tuples".  Should
+** work with any doclist type, though both inputs and the output
+** should be the same type.
 */
-SQLITE_API void *sqlite3_rollback_hook(
-  sqlite3 *db,              /* Attach the hook to this database */
-  void (*xCallback)(void*), /* Callback function */
-  void *pArg                /* Argument to the function */
-){
-  void *pRet;
-  sqlite3_mutex_enter(db->mutex);
-  pRet = db->pRollbackArg;
-  db->xRollbackCallback = xCallback;
-  db->pRollbackArg = pArg;
-  sqlite3_mutex_leave(db->mutex);
-  return pRet;
+static void posListUnion(DLReader *pLeft, DLReader *pRight, DLWriter *pOut){
+  PLReader left, right;
+  PLWriter writer;
+
+  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
+  assert( pLeft->iType==pRight->iType );
+  assert( pLeft->iType==pOut->iType );
+
+  plrInit(&left, pLeft);
+  plrInit(&right, pRight);
+  plwInit(&writer, pOut, dlrDocid(pLeft));
+
+  while( !plrAtEnd(&left) || !plrAtEnd(&right) ){
+    int c = posListCmp(&left, &right);
+    if( c<0 ){
+      plwCopy(&writer, &left);
+      plrStep(&left);
+    }else if( c>0 ){
+      plwCopy(&writer, &right);
+      plrStep(&right);
+    }else{
+      plwCopy(&writer, &left);
+      plrStep(&left);
+      plrStep(&right);
+    }
+  }
+
+  plwTerminate(&writer);
+  plwDestroy(&writer);
+  plrDestroy(&left);
+  plrDestroy(&right);
 }
 
-/*
-** This routine is called to create a connection to a database BTree
-** driver.  If zFilename is the name of a file, then that file is
-** opened and used.  If zFilename is the magic name ":memory:" then
-** the database is stored in memory (and is thus forgotten as soon as
-** the connection is closed.)  If zFilename is NULL then the database
-** is a "virtual" database for transient use only and is deleted as
-** soon as the connection is closed.
-**
-** A virtual database can be either a disk file (that is automatically
-** deleted when the file is closed) or it an be held entirely in memory,
-** depending on the values of the TEMP_STORE compile-time macro and the
-** db->temp_store variable, according to the following chart:
-**
-**       TEMP_STORE     db->temp_store     Location of temporary database
-**       ----------     --------------     ------------------------------
-**           0               any             file
-**           1                1              file
-**           1                2              memory
-**           1                0              file
-**           2                1              file
-**           2                2              memory
-**           2                0              memory
-**           3               any             memory
+/* Write the union of doclists in pLeft and pRight to pOut.  For
+** docids in common between the inputs, the union of the position
+** lists is written.  Inputs and outputs are always type DL_DEFAULT.
 */
-SQLITE_PRIVATE int sqlite3BtreeFactory(
-  const sqlite3 *db,        /* Main database when opening aux otherwise 0 */
-  const char *zFilename,    /* Name of the file containing the BTree database */
-  int omitJournal,          /* if TRUE then do not journal this file */
-  int nCache,               /* How many pages in the page cache */
-  int vfsFlags,             /* Flags passed through to vfsOpen */
-  Btree **ppBtree           /* Pointer to new Btree object written here */
+static void docListUnion(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  DataBuffer *pOut      /* Write the combined doclist here */
 ){
-  int btFlags = 0;
-  int rc;
-  
-  assert( sqlite3_mutex_held(db->mutex) );
-  assert( ppBtree != 0);
-  if( omitJournal ){
-    btFlags |= BTREE_OMIT_JOURNAL;
-  }
-  if( db->flags & SQLITE_NoReadlock ){
-    btFlags |= BTREE_NO_READLOCK;
+  DLReader left, right;
+  DLWriter writer;
+
+  if( nLeft==0 ){
+    if( nRight!=0) dataBufferAppend(pOut, pRight, nRight);
+    return;
   }
-  if( zFilename==0 ){
-#if TEMP_STORE==0
-    /* Do nothing */
-#endif
-#ifndef SQLITE_OMIT_MEMORYDB
-#if TEMP_STORE==1
-    if( db->temp_store==2 ) zFilename = ":memory:";
-#endif
-#if TEMP_STORE==2
-    if( db->temp_store!=1 ) zFilename = ":memory:";
-#endif
-#if TEMP_STORE==3
-    zFilename = ":memory:";
-#endif
-#endif /* SQLITE_OMIT_MEMORYDB */
+  if( nRight==0 ){
+    dataBufferAppend(pOut, pLeft, nLeft);
+    return;
   }
 
-  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (zFilename==0 || *zFilename==0) ){
-    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
-  }
-  rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
-  if( rc==SQLITE_OK ){
-    sqlite3BtreeSetCacheSize(*ppBtree, nCache);
+  dlrInit(&left, DL_DEFAULT, pLeft, nLeft);
+  dlrInit(&right, DL_DEFAULT, pRight, nRight);
+  dlwInit(&writer, DL_DEFAULT, pOut);
+
+  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
+    if( dlrAtEnd(&right) ){
+      dlwCopy(&writer, &left);
+      dlrStep(&left);
+    }else if( dlrAtEnd(&left) ){
+      dlwCopy(&writer, &right);
+      dlrStep(&right);
+    }else if( dlrDocid(&left)<dlrDocid(&right) ){
+      dlwCopy(&writer, &left);
+      dlrStep(&left);
+    }else if( dlrDocid(&left)>dlrDocid(&right) ){
+      dlwCopy(&writer, &right);
+      dlrStep(&right);
+    }else{
+      posListUnion(&left, &right, &writer);
+      dlrStep(&left);
+      dlrStep(&right);
+    }
   }
-  return rc;
+
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
 }
 
-/*
-** Return UTF-8 encoded English language explanation of the most recent
-** error.
+/* 
+** This function is used as part of the implementation of phrase and
+** NEAR matching.
+**
+** pLeft and pRight are DLReaders positioned to the same docid in
+** lists of type DL_POSITION. This function writes an entry to the
+** DLWriter pOut for each position in pRight that is less than
+** (nNear+1) greater (but not equal to or smaller) than a position 
+** in pLeft. For example, if nNear is 0, and the positions contained
+** by pLeft and pRight are:
+**
+**    pLeft:  5 10 15 20
+**    pRight: 6  9 17 21
+**
+** then the docid is added to pOut. If pOut is of type DL_POSITIONS,
+** then a positionids "6" and "21" are also added to pOut.
+**
+** If boolean argument isSaveLeft is true, then positionids are copied
+** from pLeft instead of pRight. In the example above, the positions "5"
+** and "20" would be added instead of "6" and "21".
 */
-SQLITE_API const char *sqlite3_errmsg(sqlite3 *db){
-  const char *z;
-  if( !db ){
-    return sqlite3ErrStr(SQLITE_NOMEM);
-  }
-  if( !sqlite3SafetyCheckSickOrOk(db) || db->errCode==SQLITE_MISUSE ){
-    return sqlite3ErrStr(SQLITE_MISUSE);
+static void posListPhraseMerge(
+  DLReader *pLeft, 
+  DLReader *pRight,
+  int nNear,
+  int isSaveLeft,
+  DLWriter *pOut
+){
+  PLReader left, right;
+  PLWriter writer;
+  int match = 0;
+
+  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
+  assert( pOut->iType!=DL_POSITIONS_OFFSETS );
+
+  plrInit(&left, pLeft);
+  plrInit(&right, pRight);
+
+  while( !plrAtEnd(&left) && !plrAtEnd(&right) ){
+    if( plrColumn(&left)<plrColumn(&right) ){
+      plrStep(&left);
+    }else if( plrColumn(&left)>plrColumn(&right) ){
+      plrStep(&right);
+    }else if( plrPosition(&left)>=plrPosition(&right) ){
+      plrStep(&right);
+    }else{
+      if( (plrPosition(&right)-plrPosition(&left))<=(nNear+1) ){
+        if( !match ){
+          plwInit(&writer, pOut, dlrDocid(pLeft));
+          match = 1;
+        }
+        if( !isSaveLeft ){
+          plwAdd(&writer, plrColumn(&right), plrPosition(&right), 0, 0);
+        }else{
+          plwAdd(&writer, plrColumn(&left), plrPosition(&left), 0, 0);
+        }
+        plrStep(&right);
+      }else{
+        plrStep(&left);
+      }
+    }
   }
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  z = (char*)sqlite3_value_text(db->pErr);
-  if( z==0 ){
-    z = sqlite3ErrStr(db->errCode);
+
+  if( match ){
+    plwTerminate(&writer);
+    plwDestroy(&writer);
   }
-  sqlite3_mutex_leave(db->mutex);
-  return z;
+
+  plrDestroy(&left);
+  plrDestroy(&right);
 }
 
-#ifndef SQLITE_OMIT_UTF16
 /*
-** Return UTF-16 encoded English language explanation of the most recent
-** error.
+** Compare the values pointed to by the PLReaders passed as arguments. 
+** Return -1 if the value pointed to by pLeft is considered less than
+** the value pointed to by pRight, +1 if it is considered greater
+** than it, or 0 if it is equal. i.e.
+**
+**     (*pLeft - *pRight)
+**
+** A PLReader that is in the EOF condition is considered greater than
+** any other. If neither argument is in EOF state, the return value of
+** plrColumn() is used. If the plrColumn() values are equal, the
+** comparison is on the basis of plrPosition().
 */
-SQLITE_API const void *sqlite3_errmsg16(sqlite3 *db){
-  /* Because all the characters in the string are in the unicode
-  ** range 0x00-0xFF, if we pad the big-endian string with a 
-  ** zero byte, we can obtain the little-endian string with
-  ** &big_endian[1].
-  */
-  static const char outOfMemBe[] = {
-    0, 'o', 0, 'u', 0, 't', 0, ' ', 
-    0, 'o', 0, 'f', 0, ' ', 
-    0, 'm', 0, 'e', 0, 'm', 0, 'o', 0, 'r', 0, 'y', 0, 0, 0
-  };
-  static const char misuseBe [] = {
-    0, 'l', 0, 'i', 0, 'b', 0, 'r', 0, 'a', 0, 'r', 0, 'y', 0, ' ', 
-    0, 'r', 0, 'o', 0, 'u', 0, 't', 0, 'i', 0, 'n', 0, 'e', 0, ' ', 
-    0, 'c', 0, 'a', 0, 'l', 0, 'l', 0, 'e', 0, 'd', 0, ' ', 
-    0, 'o', 0, 'u', 0, 't', 0, ' ', 
-    0, 'o', 0, 'f', 0, ' ', 
-    0, 's', 0, 'e', 0, 'q', 0, 'u', 0, 'e', 0, 'n', 0, 'c', 0, 'e', 0, 0, 0
-  };
+static int plrCompare(PLReader *pLeft, PLReader *pRight){
+  assert(!plrAtEnd(pLeft) || !plrAtEnd(pRight));
 
-  const void *z;
-  if( !db ){
-    return (void *)(&outOfMemBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
-  }
-  if( !sqlite3SafetyCheckSickOrOk(db) || db->errCode==SQLITE_MISUSE ){
-    return (void *)(&misuseBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
-  }
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  z = sqlite3_value_text16(db->pErr);
-  if( z==0 ){
-    sqlite3ValueSetStr(db->pErr, -1, sqlite3ErrStr(db->errCode),
-         SQLITE_UTF8, SQLITE_STATIC);
-    z = sqlite3_value_text16(db->pErr);
+  if( plrAtEnd(pRight) || plrAtEnd(pLeft) ){
+    return (plrAtEnd(pRight) ? -1 : 1);
   }
-  sqlite3ApiExit(0, 0);
-  sqlite3_mutex_leave(db->mutex);
-  return z;
-}
-#endif /* SQLITE_OMIT_UTF16 */
-
-/*
-** Return the most recent error code generated by an SQLite routine. If NULL is
-** passed to this function, we assume a malloc() failed during sqlite3_open().
-*/
-SQLITE_API int sqlite3_errcode(sqlite3 *db){
-  if( db && !sqlite3SafetyCheckSickOrOk(db) ){
-    return SQLITE_MISUSE;
+  if( plrColumn(pLeft)!=plrColumn(pRight) ){
+    return ((plrColumn(pLeft)<plrColumn(pRight)) ? -1 : 1);
   }
-  if( !db || db->mallocFailed ){
-    return SQLITE_NOMEM;
+  if( plrPosition(pLeft)!=plrPosition(pRight) ){
+    return ((plrPosition(pLeft)<plrPosition(pRight)) ? -1 : 1);
   }
-  return db->errCode & db->errMask;
+  return 0;
 }
 
-/*
-** Create a new collating function for database "db".  The name is zName
-** and the encoding is enc.
+/* We have two doclists with positions:  pLeft and pRight. Depending
+** on the value of the nNear parameter, perform either a phrase
+** intersection (if nNear==0) or a NEAR intersection (if nNear>0)
+** and write the results into pOut.
+**
+** A phrase intersection means that two documents only match
+** if pLeft.iPos+1==pRight.iPos.
+**
+** A NEAR intersection means that two documents only match if 
+** (abs(pLeft.iPos-pRight.iPos)<nNear).
+**
+** If a NEAR intersection is requested, then the nPhrase argument should
+** be passed the number of tokens in the two operands to the NEAR operator
+** combined. For example:
+**
+**       Query syntax               nPhrase
+**      ------------------------------------
+**       "A B C" NEAR "D E"         5
+**       A NEAR B                   2
+**
+** iType controls the type of data written to pOut.  If iType is
+** DL_POSITIONS, the positions are those from pRight.
 */
-static int createCollation(
-  sqlite3* db, 
-  const char *zName, 
-  int enc, 
-  void* pCtx,
-  int(*xCompare)(void*,int,const void*,int,const void*),
-  void(*xDel)(void*)
+static void docListPhraseMerge(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  int nNear,            /* 0 for a phrase merge, non-zero for a NEAR merge */
+  int nPhrase,          /* Number of tokens in left+right operands to NEAR */
+  DocListType iType,    /* Type of doclist to write to pOut */
+  DataBuffer *pOut      /* Write the combined doclist here */
 ){
-  CollSeq *pColl;
-  int enc2;
-  
-  assert( sqlite3_mutex_held(db->mutex) );
+  DLReader left, right;
+  DLWriter writer;
 
-  /* If SQLITE_UTF16 is specified as the encoding type, transform this
-  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
-  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
-  */
-  enc2 = enc & ~SQLITE_UTF16_ALIGNED;
-  if( enc2==SQLITE_UTF16 ){
-    enc2 = SQLITE_UTF16NATIVE;
-  }
+  if( nLeft==0 || nRight==0 ) return;
 
-  if( (enc2&~3)!=0 ){
-    sqlite3Error(db, SQLITE_ERROR, "unknown encoding");
-    return SQLITE_ERROR;
-  }
+  assert( iType!=DL_POSITIONS_OFFSETS );
 
-  /* Check if this call is removing or replacing an existing collation 
-  ** sequence. If so, and there are active VMs, return busy. If there
-  ** are no active VMs, invalidate any pre-compiled statements.
-  */
-  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 0);
-  if( pColl && pColl->xCmp ){
-    if( db->activeVdbeCnt ){
-      sqlite3Error(db, SQLITE_BUSY, 
-        "Unable to delete/modify collation sequence due to active statements");
-      return SQLITE_BUSY;
-    }
-    sqlite3ExpirePreparedStatements(db);
+  dlrInit(&left, DL_POSITIONS, pLeft, nLeft);
+  dlrInit(&right, DL_POSITIONS, pRight, nRight);
+  dlwInit(&writer, iType, pOut);
 
-    /* If collation sequence pColl was created directly by a call to
-    ** sqlite3_create_collation, and not generated by synthCollSeq(),
-    ** then any copies made by synthCollSeq() need to be invalidated.
-    ** Also, collation destructor - CollSeq.xDel() - function may need
-    ** to be called.
-    */ 
-    if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
-      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName, strlen(zName));
-      int j;
-      for(j=0; j<3; j++){
-        CollSeq *p = &aColl[j];
-        if( p->enc==pColl->enc ){
-          if( p->xDel ){
-            p->xDel(p->pUser);
-          }
-          p->xCmp = 0;
-        }
-      }
-    }
-  }
+  while( !dlrAtEnd(&left) && !dlrAtEnd(&right) ){
+    if( dlrDocid(&left)<dlrDocid(&right) ){
+      dlrStep(&left);
+    }else if( dlrDocid(&right)<dlrDocid(&left) ){
+      dlrStep(&right);
+    }else{
+      if( nNear==0 ){
+        posListPhraseMerge(&left, &right, 0, 0, &writer);
+      }else{
+        /* This case occurs when two terms (simple terms or phrases) are
+         * connected by a NEAR operator, span (nNear+1). i.e.
+         *
+         *     '"terrible company" NEAR widget'
+         */
+        DataBuffer one = {0, 0, 0};
+        DataBuffer two = {0, 0, 0};
 
-  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 1);
-  if( pColl ){
-    pColl->xCmp = xCompare;
-    pColl->pUser = pCtx;
-    pColl->xDel = xDel;
-    pColl->enc = enc2 | (enc & SQLITE_UTF16_ALIGNED);
-  }
-  sqlite3Error(db, SQLITE_OK, 0);
-  return SQLITE_OK;
-}
+        DLWriter dlwriter2;
+        DLReader dr1 = {0, 0, 0, 0, 0}; 
+        DLReader dr2 = {0, 0, 0, 0, 0};
 
+        dlwInit(&dlwriter2, iType, &one);
+        posListPhraseMerge(&right, &left, nNear-3+nPhrase, 1, &dlwriter2);
+        dlwInit(&dlwriter2, iType, &two);
+        posListPhraseMerge(&left, &right, nNear-1, 0, &dlwriter2);
 
-/*
-** This array defines hard upper bounds on limit values.  The
-** initializer must be kept in sync with the SQLITE_LIMIT_*
-** #defines in sqlite3.h.
-*/
-static const int aHardLimit[] = {
-  SQLITE_MAX_LENGTH,
-  SQLITE_MAX_SQL_LENGTH,
-  SQLITE_MAX_COLUMN,
-  SQLITE_MAX_EXPR_DEPTH,
-  SQLITE_MAX_COMPOUND_SELECT,
-  SQLITE_MAX_VDBE_OP,
-  SQLITE_MAX_FUNCTION_ARG,
-  SQLITE_MAX_ATTACHED,
-  SQLITE_MAX_LIKE_PATTERN_LENGTH,
-  SQLITE_MAX_VARIABLE_NUMBER,
-};
+        if( one.nData) dlrInit(&dr1, iType, one.pData, one.nData);
+        if( two.nData) dlrInit(&dr2, iType, two.pData, two.nData);
 
-/*
-** Make sure the hard limits are set to reasonable values
-*/
-#if SQLITE_MAX_LENGTH<100
-# error SQLITE_MAX_LENGTH must be at least 100
-#endif
-#if SQLITE_MAX_SQL_LENGTH<100
-# error SQLITE_MAX_SQL_LENGTH must be at least 100
-#endif
-#if SQLITE_MAX_SQL_LENGTH>SQLITE_MAX_LENGTH
-# error SQLITE_MAX_SQL_LENGTH must not be greater than SQLITE_MAX_LENGTH
-#endif
-#if SQLITE_MAX_COMPOUND_SELECT<2
-# error SQLITE_MAX_COMPOUND_SELECT must be at least 2
-#endif
-#if SQLITE_MAX_VDBE_OP<40
-# error SQLITE_MAX_VDBE_OP must be at least 40
-#endif
-#if SQLITE_MAX_FUNCTION_ARG<0 || SQLITE_MAX_FUNCTION_ARG>255
-# error SQLITE_MAX_FUNCTION_ARG must be between 0 and 255
-#endif
-#if SQLITE_MAX_ATTACH<0 || SQLITE_MAX_ATTACH>30
-# error SQLITE_MAX_ATTACH must be between 0 and 30
-#endif
-#if SQLITE_MAX_LIKE_PATTERN_LENGTH<1
-# error SQLITE_MAX_LIKE_PATTERN_LENGTH must be at least 1
-#endif
-#if SQLITE_MAX_VARIABLE_NUMBER<1
-# error SQLITE_MAX_VARIABLE_NUMBER must be at least 1
-#endif
+        if( !dlrAtEnd(&dr1) || !dlrAtEnd(&dr2) ){
+          PLReader pr1 = {0};
+          PLReader pr2 = {0};
 
+          PLWriter plwriter;
+          plwInit(&plwriter, &writer, dlrDocid(dlrAtEnd(&dr1)?&dr2:&dr1));
 
-/*
-** Change the value of a limit.  Report the old value.
-** If an invalid limit index is supplied, report -1.
-** Make no changes but still report the old value if the
-** new limit is negative.
-**
-** A new lower limit does not shrink existing constructs.
-** It merely prevents new constructs that exceed the limit
-** from forming.
-*/
-SQLITE_API int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
-  int oldLimit;
-  if( limitId<0 || limitId>=SQLITE_N_LIMIT ){
-    return -1;
-  }
-  oldLimit = db->aLimit[limitId];
-  if( newLimit>=0 ){
-    if( newLimit>aHardLimit[limitId] ){
-      newLimit = aHardLimit[limitId];
+          if( one.nData ) plrInit(&pr1, &dr1);
+          if( two.nData ) plrInit(&pr2, &dr2);
+          while( !plrAtEnd(&pr1) || !plrAtEnd(&pr2) ){
+            int iCompare = plrCompare(&pr1, &pr2);
+            switch( iCompare ){
+              case -1:
+                plwCopy(&plwriter, &pr1);
+                plrStep(&pr1);
+                break;
+              case 1:
+                plwCopy(&plwriter, &pr2);
+                plrStep(&pr2);
+                break;
+              case 0:
+                plwCopy(&plwriter, &pr1);
+                plrStep(&pr1);
+                plrStep(&pr2);
+                break;
+            }
+          }
+          plwTerminate(&plwriter);
+        }
+        dataBufferDestroy(&one);
+        dataBufferDestroy(&two);
+      }
+      dlrStep(&left);
+      dlrStep(&right);
     }
-    db->aLimit[limitId] = newLimit;
   }
-  return oldLimit;
+
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
 }
 
-/*
-** This routine does the work of opening a database on behalf of
-** sqlite3_open() and sqlite3_open16(). The database filename "zFilename"  
-** is UTF-8 encoded.
+/* We have two DL_DOCIDS doclists:  pLeft and pRight.
+** Write the intersection of these two doclists into pOut as a
+** DL_DOCIDS doclist.
 */
-static int openDatabase(
-  const char *zFilename, /* Database filename UTF-8 encoded */
-  sqlite3 **ppDb,        /* OUT: Returned database handle */
-  unsigned flags,        /* Operational flags */
-  const char *zVfs       /* Name of the VFS to use */
+static void docListAndMerge(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  DataBuffer *pOut      /* Write the combined doclist here */
 ){
-  sqlite3 *db;
-  int rc;
-  CollSeq *pColl;
-
-  /* Remove harmful bits from the flags parameter */
-  flags &=  ~( SQLITE_OPEN_DELETEONCLOSE |
-               SQLITE_OPEN_MAIN_DB |
-               SQLITE_OPEN_TEMP_DB | 
-               SQLITE_OPEN_TRANSIENT_DB | 
-               SQLITE_OPEN_MAIN_JOURNAL | 
-               SQLITE_OPEN_TEMP_JOURNAL | 
-               SQLITE_OPEN_SUBJOURNAL | 
-               SQLITE_OPEN_MASTER_JOURNAL
-             );
-
-  /* Allocate the sqlite data structure */
-  db = sqlite3MallocZero( sizeof(sqlite3) );
-  if( db==0 ) goto opendb_out;
-  db->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
-  if( db->mutex==0 ){
-    sqlite3_free(db);
-    db = 0;
-    goto opendb_out;
-  }
-  sqlite3_mutex_enter(db->mutex);
-  db->errMask = 0xff;
-  db->priorNewRowid = 0;
-  db->nDb = 2;
-  db->magic = SQLITE_MAGIC_BUSY;
-  db->aDb = db->aDbStatic;
-  assert( sizeof(db->aLimit)==sizeof(aHardLimit) );
-  memcpy(db->aLimit, aHardLimit, sizeof(db->aLimit));
-  db->autoCommit = 1;
-  db->nextAutovac = -1;
-  db->nextPagesize = 0;
-  db->flags |= SQLITE_ShortColNames
-#if SQLITE_DEFAULT_FILE_FORMAT<4
-                 | SQLITE_LegacyFileFmt
-#endif
-#ifdef SQLITE_ENABLE_LOAD_EXTENSION
-                 | SQLITE_LoadExtension
-#endif
-      ;
-  sqlite3HashInit(&db->aFunc, SQLITE_HASH_STRING, 0);
-  sqlite3HashInit(&db->aCollSeq, SQLITE_HASH_STRING, 0);
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3HashInit(&db->aModule, SQLITE_HASH_STRING, 0);
-#endif
-
-  db->pVfs = sqlite3_vfs_find(zVfs);
-  if( !db->pVfs ){
-    rc = SQLITE_ERROR;
-    db->magic = SQLITE_MAGIC_SICK;
-    sqlite3Error(db, rc, "no such vfs: %s", zVfs);
-    goto opendb_out;
-  }
-
-  /* Add the default collation sequence BINARY. BINARY works for both UTF-8
-  ** and UTF-16, so add a version for each to avoid any unnecessary
-  ** conversions. The only error that can occur here is a malloc() failure.
-  */
-  createCollation(db, "BINARY", SQLITE_UTF8, 0, binCollFunc, 0);
-  createCollation(db, "BINARY", SQLITE_UTF16BE, 0, binCollFunc, 0);
-  createCollation(db, "BINARY", SQLITE_UTF16LE, 0, binCollFunc, 0);
-  createCollation(db, "RTRIM", SQLITE_UTF8, (void*)1, binCollFunc, 0);
-  if( db->mallocFailed ){
-    db->magic = SQLITE_MAGIC_SICK;
-    goto opendb_out;
-  }
-  db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
-  assert( db->pDfltColl!=0 );
+  DLReader left, right;
+  DLWriter writer;
 
-  /* Also add a UTF-8 case-insensitive collation sequence. */
-  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);
+  if( nLeft==0 || nRight==0 ) return;
 
-  /* Set flags on the built-in collating sequences */
-  db->pDfltColl->type = SQLITE_COLL_BINARY;
-  pColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "NOCASE", 6, 0);
-  if( pColl ){
-    pColl->type = SQLITE_COLL_NOCASE;
-  }
+  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
+  dlrInit(&right, DL_DOCIDS, pRight, nRight);
+  dlwInit(&writer, DL_DOCIDS, pOut);
 
-  /* Open the backend database driver */
-  db->openFlags = flags;
-  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE, 
-                           flags | SQLITE_OPEN_MAIN_DB,
-                           &db->aDb[0].pBt);
-  if( rc!=SQLITE_OK ){
-    sqlite3Error(db, rc, 0);
-    db->magic = SQLITE_MAGIC_SICK;
-    goto opendb_out;
+  while( !dlrAtEnd(&left) && !dlrAtEnd(&right) ){
+    if( dlrDocid(&left)<dlrDocid(&right) ){
+      dlrStep(&left);
+    }else if( dlrDocid(&right)<dlrDocid(&left) ){
+      dlrStep(&right);
+    }else{
+      dlwAdd(&writer, dlrDocid(&left));
+      dlrStep(&left);
+      dlrStep(&right);
+    }
   }
-  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
-  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);
-
-
-  /* The default safety_level for the main database is 'full'; for the temp
-  ** database it is 'NONE'. This matches the pager layer defaults.  
-  */
-  db->aDb[0].zName = "main";
-  db->aDb[0].safety_level = 3;
-#ifndef SQLITE_OMIT_TEMPDB
-  db->aDb[1].zName = "temp";
-  db->aDb[1].safety_level = 1;
-#endif
 
-  db->magic = SQLITE_MAGIC_OPEN;
-  if( db->mallocFailed ){
-    goto opendb_out;
-  }
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
+}
 
-  /* Register all built-in functions, but do not attempt to read the
-  ** database schema yet. This is delayed until the first time the database
-  ** is accessed.
-  */
-  sqlite3Error(db, SQLITE_OK, 0);
-  sqlite3RegisterBuiltinFunctions(db);
+/* We have two DL_DOCIDS doclists:  pLeft and pRight.
+** Write the union of these two doclists into pOut as a
+** DL_DOCIDS doclist.
+*/
+static void docListOrMerge(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  DataBuffer *pOut      /* Write the combined doclist here */
+){
+  DLReader left, right;
+  DLWriter writer;
 
-  /* Load automatic extensions - extensions that have been registered
-  ** using the sqlite3_automatic_extension() API.
-  */
-  (void)sqlite3AutoLoadExtensions(db);
-  if( sqlite3_errcode(db)!=SQLITE_OK ){
-    goto opendb_out;
+  if( nLeft==0 ){
+    if( nRight!=0 ) dataBufferAppend(pOut, pRight, nRight);
+    return;
   }
-
-#ifdef SQLITE_ENABLE_FTS1
-  if( !db->mallocFailed ){
-    extern int sqlite3Fts1Init(sqlite3*);
-    rc = sqlite3Fts1Init(db);
+  if( nRight==0 ){
+    dataBufferAppend(pOut, pLeft, nLeft);
+    return;
   }
-#endif
 
-#ifdef SQLITE_ENABLE_FTS2
-  if( !db->mallocFailed && rc==SQLITE_OK ){
-    extern int sqlite3Fts2Init(sqlite3*);
-    rc = sqlite3Fts2Init(db);
-  }
-#endif
+  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
+  dlrInit(&right, DL_DOCIDS, pRight, nRight);
+  dlwInit(&writer, DL_DOCIDS, pOut);
 
-#ifdef SQLITE_ENABLE_FTS3
-  if( !db->mallocFailed && rc==SQLITE_OK ){
-    rc = sqlite3Fts3Init(db);
+  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
+    if( dlrAtEnd(&right) ){
+      dlwAdd(&writer, dlrDocid(&left));
+      dlrStep(&left);
+    }else if( dlrAtEnd(&left) ){
+      dlwAdd(&writer, dlrDocid(&right));
+      dlrStep(&right);
+    }else if( dlrDocid(&left)<dlrDocid(&right) ){
+      dlwAdd(&writer, dlrDocid(&left));
+      dlrStep(&left);
+    }else if( dlrDocid(&right)<dlrDocid(&left) ){
+      dlwAdd(&writer, dlrDocid(&right));
+      dlrStep(&right);
+    }else{
+      dlwAdd(&writer, dlrDocid(&left));
+      dlrStep(&left);
+      dlrStep(&right);
+    }
   }
-#endif
 
-#ifdef SQLITE_ENABLE_ICU
-  if( !db->mallocFailed && rc==SQLITE_OK ){
-    extern int sqlite3IcuInit(sqlite3*);
-    rc = sqlite3IcuInit(db);
-  }
-#endif
-  sqlite3Error(db, rc, 0);
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
+}
 
-  /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
-  ** mode.  -DSQLITE_DEFAULT_LOCKING_MODE=0 make NORMAL the default locking
-  ** mode.  Doing nothing at all also makes NORMAL the default.
-  */
-#ifdef SQLITE_DEFAULT_LOCKING_MODE
-  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
-  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
-                          SQLITE_DEFAULT_LOCKING_MODE);
-#endif
+/* We have two DL_DOCIDS doclists:  pLeft and pRight.
+** Write into pOut as DL_DOCIDS doclist containing all documents that
+** occur in pLeft but not in pRight.
+*/
+static void docListExceptMerge(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  DataBuffer *pOut      /* Write the combined doclist here */
+){
+  DLReader left, right;
+  DLWriter writer;
 
-opendb_out:
-  if( db ){
-    assert( db->mutex!=0 );
-    sqlite3_mutex_leave(db->mutex);
+  if( nLeft==0 ) return;
+  if( nRight==0 ){
+    dataBufferAppend(pOut, pLeft, nLeft);
+    return;
   }
-  if( SQLITE_NOMEM==(rc = sqlite3_errcode(db)) ){
-    sqlite3_close(db);
-    db = 0;
+
+  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
+  dlrInit(&right, DL_DOCIDS, pRight, nRight);
+  dlwInit(&writer, DL_DOCIDS, pOut);
+
+  while( !dlrAtEnd(&left) ){
+    while( !dlrAtEnd(&right) && dlrDocid(&right)<dlrDocid(&left) ){
+      dlrStep(&right);
+    }
+    if( dlrAtEnd(&right) || dlrDocid(&left)<dlrDocid(&right) ){
+      dlwAdd(&writer, dlrDocid(&left));
+    }
+    dlrStep(&left);
   }
-  *ppDb = db;
-  return sqlite3ApiExit(0, rc);
+
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
 }
 
-/*
-** Open a new database handle.
-*/
-SQLITE_API int sqlite3_open(
-  const char *zFilename, 
-  sqlite3 **ppDb 
-){
-  return openDatabase(zFilename, ppDb,
-                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
+static char *string_dup_n(const char *s, int n){
+  char *str = sqlite3_malloc(n + 1);
+  memcpy(str, s, n);
+  str[n] = '\0';
+  return str;
 }
-SQLITE_API int sqlite3_open_v2(
-  const char *filename,   /* Database filename (UTF-8) */
-  sqlite3 **ppDb,         /* OUT: SQLite db handle */
-  int flags,              /* Flags */
-  const char *zVfs        /* Name of VFS module to use */
-){
-  return openDatabase(filename, ppDb, flags, zVfs);
+
+/* Duplicate a string; the caller must free() the returned string.
+ * (We don't use strdup() since it is not part of the standard C library and
+ * may not be available everywhere.) */
+static char *string_dup(const char *s){
+  return string_dup_n(s, strlen(s));
 }
 
-#ifndef SQLITE_OMIT_UTF16
-/*
-** Open a new database handle.
-*/
-SQLITE_API int sqlite3_open16(
-  const void *zFilename, 
-  sqlite3 **ppDb
-){
-  char const *zFilename8;   /* zFilename encoded in UTF-8 instead of UTF-16 */
-  sqlite3_value *pVal;
-  int rc = SQLITE_NOMEM;
+/* Format a string, replacing each occurrence of the % character with
+ * zDb.zName.  This may be more convenient than sqlite_mprintf()
+ * when one string is used repeatedly in a format string.
+ * The caller must free() the returned string. */
+static char *string_format(const char *zFormat,
+                           const char *zDb, const char *zName){
+  const char *p;
+  size_t len = 0;
+  size_t nDb = strlen(zDb);
+  size_t nName = strlen(zName);
+  size_t nFullTableName = nDb+1+nName;
+  char *result;
+  char *r;
 
-  assert( zFilename );
-  assert( ppDb );
-  *ppDb = 0;
-  pVal = sqlite3ValueNew(0);
-  sqlite3ValueSetStr(pVal, -1, zFilename, SQLITE_UTF16NATIVE, SQLITE_STATIC);
-  zFilename8 = sqlite3ValueText(pVal, SQLITE_UTF8);
-  if( zFilename8 ){
-    rc = openDatabase(zFilename8, ppDb,
-                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
-    assert( *ppDb || rc==SQLITE_NOMEM );
-    if( rc==SQLITE_OK && !DbHasProperty(*ppDb, 0, DB_SchemaLoaded) ){
-      ENC(*ppDb) = SQLITE_UTF16NATIVE;
-    }
+  /* first compute length needed */
+  for(p = zFormat ; *p ; ++p){
+    len += (*p=='%' ? nFullTableName : 1);
   }
-  sqlite3ValueFree(pVal);
+  len += 1;  /* for null terminator */
 
-  return sqlite3ApiExit(0, rc);
+  r = result = sqlite3_malloc(len);
+  for(p = zFormat; *p; ++p){
+    if( *p=='%' ){
+      memcpy(r, zDb, nDb);
+      r += nDb;
+      *r++ = '.';
+      memcpy(r, zName, nName);
+      r += nName;
+    } else {
+      *r++ = *p;
+    }
+  }
+  *r++ = '\0';
+  assert( r == result + len );
+  return result;
 }
-#endif /* SQLITE_OMIT_UTF16 */
 
-/*
-** Register a new collation sequence with the database handle db.
-*/
-SQLITE_API int sqlite3_create_collation(
-  sqlite3* db, 
-  const char *zName, 
-  int enc, 
-  void* pCtx,
-  int(*xCompare)(void*,int,const void*,int,const void*)
-){
+static int sql_exec(sqlite3 *db, const char *zDb, const char *zName,
+                    const char *zFormat){
+  char *zCommand = string_format(zFormat, zDb, zName);
   int rc;
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  rc = createCollation(db, zName, enc, pCtx, xCompare, 0);
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
+  FTSTRACE(("FTS3 sql: %s\n", zCommand));
+  rc = sqlite3_exec(db, zCommand, NULL, 0, NULL);
+  sqlite3_free(zCommand);
   return rc;
 }
 
-/*
-** Register a new collation sequence with the database handle db.
-*/
-SQLITE_API int sqlite3_create_collation_v2(
-  sqlite3* db, 
-  const char *zName, 
-  int enc, 
-  void* pCtx,
-  int(*xCompare)(void*,int,const void*,int,const void*),
-  void(*xDel)(void*)
-){
+static int sql_prepare(sqlite3 *db, const char *zDb, const char *zName,
+                       sqlite3_stmt **ppStmt, const char *zFormat){
+  char *zCommand = string_format(zFormat, zDb, zName);
   int rc;
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  rc = createCollation(db, zName, enc, pCtx, xCompare, xDel);
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
+  FTSTRACE(("FTS3 prepare: %s\n", zCommand));
+  rc = sqlite3_prepare_v2(db, zCommand, -1, ppStmt, NULL);
+  sqlite3_free(zCommand);
   return rc;
 }
 
-#ifndef SQLITE_OMIT_UTF16
-/*
-** Register a new collation sequence with the database handle db.
-*/
-SQLITE_API int sqlite3_create_collation16(
-  sqlite3* db, 
-  const char *zName, 
-  int enc, 
-  void* pCtx,
-  int(*xCompare)(void*,int,const void*,int,const void*)
-){
-  int rc = SQLITE_OK;
-  char *zName8;
-  sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
-  zName8 = sqlite3Utf16to8(db, zName, -1);
-  if( zName8 ){
-    rc = createCollation(db, zName8, enc, pCtx, xCompare, 0);
-    sqlite3_free(zName8);
-  }
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
-}
-#endif /* SQLITE_OMIT_UTF16 */
+/* end utility functions */
 
-/*
-** Register a collation sequence factory callback with the database handle
-** db. Replace any previously installed collation sequence factory.
-*/
-SQLITE_API int sqlite3_collation_needed(
-  sqlite3 *db, 
-  void *pCollNeededArg, 
-  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*)
-){
-  sqlite3_mutex_enter(db->mutex);
-  db->xCollNeeded = xCollNeeded;
-  db->xCollNeeded16 = 0;
-  db->pCollNeededArg = pCollNeededArg;
-  sqlite3_mutex_leave(db->mutex);
-  return SQLITE_OK;
-}
+/* Forward reference */
+typedef struct fulltext_vtab fulltext_vtab;
 
-#ifndef SQLITE_OMIT_UTF16
 /*
-** Register a collation sequence factory callback with the database handle
-** db. Replace any previously installed collation sequence factory.
+** An instance of the following structure keeps track of generated
+** matching-word offset information and snippets.
 */
-SQLITE_API int sqlite3_collation_needed16(
-  sqlite3 *db, 
-  void *pCollNeededArg, 
-  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*)
-){
-  sqlite3_mutex_enter(db->mutex);
-  db->xCollNeeded = 0;
-  db->xCollNeeded16 = xCollNeeded16;
-  db->pCollNeededArg = pCollNeededArg;
-  sqlite3_mutex_leave(db->mutex);
-  return SQLITE_OK;
-}
-#endif /* SQLITE_OMIT_UTF16 */
+typedef struct Snippet {
+  int nMatch;     /* Total number of matches */
+  int nAlloc;     /* Space allocated for aMatch[] */
+  struct snippetMatch { /* One entry for each matching term */
+    char snStatus;       /* Status flag for use while constructing snippets */
+    short int iCol;      /* The column that contains the match */
+    short int iTerm;     /* The index in Query.pTerms[] of the matching term */
+    int iToken;          /* The index of the matching document token */
+    short int nByte;     /* Number of bytes in the term */
+    int iStart;          /* The offset to the first character of the term */
+  } *aMatch;      /* Points to space obtained from malloc */
+  char *zOffset;  /* Text rendering of aMatch[] */
+  int nOffset;    /* strlen(zOffset) */
+  char *zSnippet; /* Snippet text */
+  int nSnippet;   /* strlen(zSnippet) */
+} Snippet;
 
-#ifndef SQLITE_OMIT_GLOBALRECOVER
-/*
-** This function is now an anachronism. It used to be used to recover from a
-** malloc() failure, but SQLite now does this automatically.
-*/
-SQLITE_API int sqlite3_global_recover(void){
-  return SQLITE_OK;
-}
-#endif
 
-/*
-** Test to see whether or not the database connection is in autocommit
-** mode.  Return TRUE if it is and FALSE if not.  Autocommit mode is on
-** by default.  Autocommit is disabled by a BEGIN statement and reenabled
-** by the next COMMIT or ROLLBACK.
-**
-******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
+typedef enum QueryType {
+  QUERY_GENERIC,   /* table scan */
+  QUERY_DOCID,     /* lookup by docid */
+  QUERY_FULLTEXT   /* QUERY_FULLTEXT + [i] is a full-text search for column i*/
+} QueryType;
+
+typedef enum fulltext_statement {
+  CONTENT_INSERT_STMT,
+  CONTENT_SELECT_STMT,
+  CONTENT_UPDATE_STMT,
+  CONTENT_DELETE_STMT,
+  CONTENT_EXISTS_STMT,
+
+  BLOCK_INSERT_STMT,
+  BLOCK_SELECT_STMT,
+  BLOCK_DELETE_STMT,
+  BLOCK_DELETE_ALL_STMT,
+
+  SEGDIR_MAX_INDEX_STMT,
+  SEGDIR_SET_STMT,
+  SEGDIR_SELECT_LEVEL_STMT,
+  SEGDIR_SPAN_STMT,
+  SEGDIR_DELETE_STMT,
+  SEGDIR_SELECT_SEGMENT_STMT,
+  SEGDIR_SELECT_ALL_STMT,
+  SEGDIR_DELETE_ALL_STMT,
+  SEGDIR_COUNT_STMT,
+
+  MAX_STMT                     /* Always at end! */
+} fulltext_statement;
+
+/* These must exactly match the enum above. */
+/* TODO(shess): Is there some risk that a statement will be used in two
+** cursors at once, e.g.  if a query joins a virtual table to itself?
+** If so perhaps we should move some of these to the cursor object.
 */
-SQLITE_API int sqlite3_get_autocommit(sqlite3 *db){
-  return db->autoCommit;
-}
+static const char *const fulltext_zStatement[MAX_STMT] = {
+  /* CONTENT_INSERT */ NULL,  /* generated in contentInsertStatement() */
+  /* CONTENT_SELECT */ NULL,  /* generated in contentSelectStatement() */
+  /* CONTENT_UPDATE */ NULL,  /* generated in contentUpdateStatement() */
+  /* CONTENT_DELETE */ "delete from %_content where docid = ?",
+  /* CONTENT_EXISTS */ "select docid from %_content limit 1",
+
+  /* BLOCK_INSERT */
+  "insert into %_segments (blockid, block) values (null, ?)",
+  /* BLOCK_SELECT */ "select block from %_segments where blockid = ?",
+  /* BLOCK_DELETE */ "delete from %_segments where blockid between ? and ?",
+  /* BLOCK_DELETE_ALL */ "delete from %_segments",
+
+  /* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
+  /* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
+  /* SEGDIR_SELECT_LEVEL */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " where level = ? order by idx",
+  /* SEGDIR_SPAN */
+  "select min(start_block), max(end_block) from %_segdir "
+  " where level = ? and start_block <> 0",
+  /* SEGDIR_DELETE */ "delete from %_segdir where level = ?",
+
+  /* NOTE(shess): The first three results of the following two
+  ** statements must match.
+  */
+  /* SEGDIR_SELECT_SEGMENT */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " where level = ? and idx = ?",
+  /* SEGDIR_SELECT_ALL */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " order by level desc, idx asc",
+  /* SEGDIR_DELETE_ALL */ "delete from %_segdir",
+  /* SEGDIR_COUNT */ "select count(*), ifnull(max(level),0) from %_segdir",
+};
 
-#ifdef SQLITE_DEBUG
 /*
-** The following routine is subtituted for constant SQLITE_CORRUPT in
-** debugging builds.  This provides a way to set a breakpoint for when
-** corruption is first detected.
+** A connection to a fulltext index is an instance of the following
+** structure.  The xCreate and xConnect methods create an instance
+** of this structure and xDestroy and xDisconnect free that instance.
+** All other methods receive a pointer to the structure as one of their
+** arguments.
 */
-SQLITE_PRIVATE int sqlite3Corrupt(void){
-  return SQLITE_CORRUPT;
-}
-#endif
+struct fulltext_vtab {
+  sqlite3_vtab base;               /* Base class used by SQLite core */
+  sqlite3 *db;                     /* The database connection */
+  const char *zDb;                 /* logical database name */
+  const char *zName;               /* virtual table name */
+  int nColumn;                     /* number of columns in virtual table */
+  char **azColumn;                 /* column names.  malloced */
+  char **azContentColumn;          /* column names in content table; malloced */
+  sqlite3_tokenizer *pTokenizer;   /* tokenizer for inserts and queries */
+
+  /* Precompiled statements which we keep as long as the table is
+  ** open.
+  */
+  sqlite3_stmt *pFulltextStatements[MAX_STMT];
+
+  /* Precompiled statements used for segment merges.  We run a
+  ** separate select across the leaf level of each tree being merged.
+  */
+  sqlite3_stmt *pLeafSelectStmts[MERGE_COUNT];
+  /* The statement used to prepare pLeafSelectStmts. */
+#define LEAF_SELECT \
+  "select block from %_segments where blockid between ? and ? order by blockid"
+
+  /* These buffer pending index updates during transactions.
+  ** nPendingData estimates the memory size of the pending data.  It
+  ** doesn't include the hash-bucket overhead, nor any malloc
+  ** overhead.  When nPendingData exceeds kPendingThreshold, the
+  ** buffer is flushed even before the transaction closes.
+  ** pendingTerms stores the data, and is only valid when nPendingData
+  ** is >=0 (nPendingData<0 means pendingTerms has not been
+  ** initialized).  iPrevDocid is the last docid written, used to make
+  ** certain we're inserting in sorted order.
+  */
+  int nPendingData;
+#define kPendingThreshold (1*1024*1024)
+  sqlite_int64 iPrevDocid;
+  fts3Hash pendingTerms;
+};
 
 /*
-** This is a convenience routine that makes sure that all thread-specific
-** data for this thread has been deallocated.
-**
-** SQLite no longer uses thread-specific data so this routine is now a
-** no-op.  It is retained for historical compatibility.
+** When the core wants to do a query, it create a cursor using a
+** call to xOpen.  This structure is an instance of a cursor.  It
+** is destroyed by xClose.
 */
-SQLITE_API void sqlite3_thread_cleanup(void){
+typedef struct fulltext_cursor {
+  sqlite3_vtab_cursor base;        /* Base class used by SQLite core */
+  QueryType iCursorType;           /* Copy of sqlite3_index_info.idxNum */
+  sqlite3_stmt *pStmt;             /* Prepared statement in use by the cursor */
+  int eof;                         /* True if at End Of Results */
+  Fts3Expr *pExpr;                 /* Parsed MATCH query string */
+  Snippet snippet;                 /* Cached snippet for the current row */
+  int iColumn;                     /* Column being searched */
+  DataBuffer result;               /* Doclist results from fulltextQuery */
+  DLReader reader;                 /* Result reader if result not empty */
+} fulltext_cursor;
+
+static fulltext_vtab *cursor_vtab(fulltext_cursor *c){
+  return (fulltext_vtab *) c->base.pVtab;
 }
 
-/*
-** Return meta information about a specific column of a database table.
-** See comment in sqlite3.h (sqlite.h.in) for details.
-*/
-#ifdef SQLITE_ENABLE_COLUMN_METADATA
-SQLITE_API int sqlite3_table_column_metadata(
-  sqlite3 *db,                /* Connection handle */
-  const char *zDbName,        /* Database name or NULL */
-  const char *zTableName,     /* Table name */
-  const char *zColumnName,    /* Column name */
-  char const **pzDataType,    /* OUTPUT: Declared data type */
-  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
-  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
-  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
-  int *pAutoinc               /* OUTPUT: True if colums is auto-increment */
-){
-  int rc;
-  char *zErrMsg = 0;
-  Table *pTab = 0;
-  Column *pCol = 0;
-  int iCol;
+static const sqlite3_module fts3Module;   /* forward declaration */
 
-  char const *zDataType = 0;
-  char const *zCollSeq = 0;
-  int notnull = 0;
-  int primarykey = 0;
-  int autoinc = 0;
+/* Return a dynamically generated statement of the form
+ *   insert into %_content (docid, ...) values (?, ...)
+ */
+static const char *contentInsertStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  int i;
 
-  /* Ensure the database schema has been loaded */
-  sqlite3_mutex_enter(db->mutex);
-  (void)sqlite3SafetyOn(db);
-  sqlite3BtreeEnterAll(db);
-  rc = sqlite3Init(db, &zErrMsg);
-  sqlite3BtreeLeaveAll(db);
-  if( SQLITE_OK!=rc ){
-    goto error_out;
-  }
+  initStringBuffer(&sb);
+  append(&sb, "insert into %_content (docid, ");
+  appendList(&sb, v->nColumn, v->azContentColumn);
+  append(&sb, ") values (?");
+  for(i=0; i<v->nColumn; ++i)
+    append(&sb, ", ?");
+  append(&sb, ")");
+  return stringBufferData(&sb);
+}
 
-  /* Locate the table in question */
-  pTab = sqlite3FindTable(db, zTableName, zDbName);
-  if( !pTab || pTab->pSelect ){
-    pTab = 0;
-    goto error_out;
-  }
+/* Return a dynamically generated statement of the form
+ *   select <content columns> from %_content where docid = ?
+ */
+static const char *contentSelectStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  initStringBuffer(&sb);
+  append(&sb, "SELECT ");
+  appendList(&sb, v->nColumn, v->azContentColumn);
+  append(&sb, " FROM %_content WHERE docid = ?");
+  return stringBufferData(&sb);
+}
 
-  /* Find the column for which info is requested */
-  if( sqlite3IsRowid(zColumnName) ){
-    iCol = pTab->iPKey;
-    if( iCol>=0 ){
-      pCol = &pTab->aCol[iCol];
-    }
-  }else{
-    for(iCol=0; iCol<pTab->nCol; iCol++){
-      pCol = &pTab->aCol[iCol];
-      if( 0==sqlite3StrICmp(pCol->zName, zColumnName) ){
-        break;
-      }
-    }
-    if( iCol==pTab->nCol ){
-      pTab = 0;
-      goto error_out;
+/* Return a dynamically generated statement of the form
+ *   update %_content set [col_0] = ?, [col_1] = ?, ...
+ *                    where docid = ?
+ */
+static const char *contentUpdateStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  int i;
+
+  initStringBuffer(&sb);
+  append(&sb, "update %_content set ");
+  for(i=0; i<v->nColumn; ++i) {
+    if( i>0 ){
+      append(&sb, ", ");
     }
+    append(&sb, v->azContentColumn[i]);
+    append(&sb, " = ?");
   }
+  append(&sb, " where docid = ?");
+  return stringBufferData(&sb);
+}
 
-  /* The following block stores the meta information that will be returned
-  ** to the caller in local variables zDataType, zCollSeq, notnull, primarykey
-  ** and autoinc. At this point there are two possibilities:
-  ** 
-  **     1. The specified column name was rowid", "oid" or "_rowid_" 
-  **        and there is no explicitly declared IPK column. 
-  **
-  **     2. The table is not a view and the column name identified an 
-  **        explicitly declared column. Copy meta information from *pCol.
-  */ 
-  if( pCol ){
-    zDataType = pCol->zType;
-    zCollSeq = pCol->zColl;
-    notnull = (pCol->notNull?1:0);
-    primarykey  = (pCol->isPrimKey?1:0);
-    autoinc = ((pTab->iPKey==iCol && pTab->autoInc)?1:0);
-  }else{
-    zDataType = "INTEGER";
-    primarykey = 1;
-  }
-  if( !zCollSeq ){
-    zCollSeq = "BINARY";
+/* Puts a freshly-prepared statement determined by iStmt in *ppStmt.
+** If the indicated statement has never been prepared, it is prepared
+** and cached, otherwise the cached version is reset.
+*/
+static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt,
+                             sqlite3_stmt **ppStmt){
+  assert( iStmt<MAX_STMT );
+  if( v->pFulltextStatements[iStmt]==NULL ){
+    const char *zStmt;
+    int rc;
+    switch( iStmt ){
+      case CONTENT_INSERT_STMT:
+        zStmt = contentInsertStatement(v); break;
+      case CONTENT_SELECT_STMT:
+        zStmt = contentSelectStatement(v); break;
+      case CONTENT_UPDATE_STMT:
+        zStmt = contentUpdateStatement(v); break;
+      default:
+        zStmt = fulltext_zStatement[iStmt];
+    }
+    rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt],
+                         zStmt);
+    if( zStmt != fulltext_zStatement[iStmt]) sqlite3_free((void *) zStmt);
+    if( rc!=SQLITE_OK ) return rc;
+  } else {
+    int rc = sqlite3_reset(v->pFulltextStatements[iStmt]);
+    if( rc!=SQLITE_OK ) return rc;
   }
 
-error_out:
-  (void)sqlite3SafetyOff(db);
-
-  /* Whether the function call succeeded or failed, set the output parameters
-  ** to whatever their local counterparts contain. If an error did occur,
-  ** this has the effect of zeroing all output parameters.
-  */
-  if( pzDataType ) *pzDataType = zDataType;
-  if( pzCollSeq ) *pzCollSeq = zCollSeq;
-  if( pNotNull ) *pNotNull = notnull;
-  if( pPrimaryKey ) *pPrimaryKey = primarykey;
-  if( pAutoinc ) *pAutoinc = autoinc;
-
-  if( SQLITE_OK==rc && !pTab ){
-    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
-        zColumnName, 0);
-    rc = SQLITE_ERROR;
-  }
-  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
-  sqlite3_free(zErrMsg);
-  rc = sqlite3ApiExit(db, rc);
-  sqlite3_mutex_leave(db->mutex);
-  return rc;
+  *ppStmt = v->pFulltextStatements[iStmt];
+  return SQLITE_OK;
 }
-#endif
 
-/*
-** Sleep for a little while.  Return the amount of time slept.
+/* Like sqlite3_step(), but convert SQLITE_DONE to SQLITE_OK and
+** SQLITE_ROW to SQLITE_ERROR.  Useful for statements like UPDATE,
+** where we expect no results.
 */
-SQLITE_API int sqlite3_sleep(int ms){
-  sqlite3_vfs *pVfs;
-  int rc;
-  pVfs = sqlite3_vfs_find(0);
-
-  /* This function works in milliseconds, but the underlying OsSleep() 
-  ** API uses microseconds. Hence the 1000's.
-  */
-  rc = (sqlite3OsSleep(pVfs, 1000*ms)/1000);
-  return rc;
+static int sql_single_step(sqlite3_stmt *s){
+  int rc = sqlite3_step(s);
+  return (rc==SQLITE_DONE) ? SQLITE_OK : rc;
 }
 
-/*
-** Enable or disable the extended result codes.
+/* Like sql_get_statement(), but for special replicated LEAF_SELECT
+** statements.  idx -1 is a special case for an uncached version of
+** the statement (used in the optimize implementation).
 */
-SQLITE_API int sqlite3_extended_result_codes(sqlite3 *db, int onoff){
-  sqlite3_mutex_enter(db->mutex);
-  db->errMask = onoff ? 0xffffffff : 0xff;
-  sqlite3_mutex_leave(db->mutex);
+/* TODO(shess) Write version for generic statements and then share
+** that between the cached-statement functions.
+*/
+static int sql_get_leaf_statement(fulltext_vtab *v, int idx,
+                                  sqlite3_stmt **ppStmt){
+  assert( idx>=-1 && idx<MERGE_COUNT );
+  if( idx==-1 ){
+    return sql_prepare(v->db, v->zDb, v->zName, ppStmt, LEAF_SELECT);
+  }else if( v->pLeafSelectStmts[idx]==NULL ){
+    int rc = sql_prepare(v->db, v->zDb, v->zName, &v->pLeafSelectStmts[idx],
+                         LEAF_SELECT);
+    if( rc!=SQLITE_OK ) return rc;
+  }else{
+    int rc = sqlite3_reset(v->pLeafSelectStmts[idx]);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  *ppStmt = v->pLeafSelectStmts[idx];
   return SQLITE_OK;
 }
 
-/*
-** Invoke the xFileControl method on a particular database.
+/* insert into %_content (docid, ...) values ([docid], [pValues])
+** If the docid contains SQL NULL, then a unique docid will be
+** generated.
 */
-SQLITE_API int sqlite3_file_control(sqlite3 *db, const char *zDbName, int op, void *pArg){
-  int rc = SQLITE_ERROR;
-  int iDb;
-  sqlite3_mutex_enter(db->mutex);
-  if( zDbName==0 ){
-    iDb = 0;
-  }else{
-    for(iDb=0; iDb<db->nDb; iDb++){
-      if( strcmp(db->aDb[iDb].zName, zDbName)==0 ) break;
-    }
+static int content_insert(fulltext_vtab *v, sqlite3_value *docid,
+                          sqlite3_value **pValues){
+  sqlite3_stmt *s;
+  int i;
+  int rc = sql_get_statement(v, CONTENT_INSERT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_value(s, 1, docid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  for(i=0; i<v->nColumn; ++i){
+    rc = sqlite3_bind_value(s, 2+i, pValues[i]);
+    if( rc!=SQLITE_OK ) return rc;
   }
-  if( iDb<db->nDb ){
-    Btree *pBtree = db->aDb[iDb].pBt;
-    if( pBtree ){
-      Pager *pPager;
-      sqlite3_file *fd;
-      sqlite3BtreeEnter(pBtree);
-      pPager = sqlite3BtreePager(pBtree);
-      assert( pPager!=0 );
-      fd = sqlite3PagerFile(pPager);
-      assert( fd!=0 );
-      if( fd->pMethods ){
-        rc = sqlite3OsFileControl(fd, op, pArg);
-      }
-      sqlite3BtreeLeave(pBtree);
-    }
+
+  return sql_single_step(s);
+}
+
+/* update %_content set col0 = pValues[0], col1 = pValues[1], ...
+ *                  where docid = [iDocid] */
+static int content_update(fulltext_vtab *v, sqlite3_value **pValues,
+                          sqlite_int64 iDocid){
+  sqlite3_stmt *s;
+  int i;
+  int rc = sql_get_statement(v, CONTENT_UPDATE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  for(i=0; i<v->nColumn; ++i){
+    rc = sqlite3_bind_value(s, 1+i, pValues[i]);
+    if( rc!=SQLITE_OK ) return rc;
   }
-  sqlite3_mutex_leave(db->mutex);
-  return rc;   
+
+  rc = sqlite3_bind_int64(s, 1+v->nColumn, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
 }
 
-/*
-** Interface to the testing logic.
-*/
-SQLITE_API int sqlite3_test_control(int op, ...){
-  int rc = 0;
-#ifndef SQLITE_OMIT_BUILTIN_TEST
-  va_list ap;
-  va_start(ap, op);
-  switch( op ){
-    /*
-    ** sqlite3_test_control(FAULT_CONFIG, fault_id, nDelay, nRepeat)
-    **
-    ** Configure a fault injector.  The specific fault injector is
-    ** identified by the fault_id argument.  (ex: SQLITE_FAULTINJECTOR_MALLOC)
-    ** The fault will occur after a delay of nDelay calls.  The fault
-    ** will repeat nRepeat times.
-    */
-    case SQLITE_TESTCTRL_FAULT_CONFIG: {
-      int id = va_arg(ap, int);
-      int nDelay = va_arg(ap, int);
-      int nRepeat = va_arg(ap, int);
-      sqlite3FaultConfig(id, nDelay, nRepeat);
-      break;
-    }
+static void freeStringArray(int nString, const char **pString){
+  int i;
 
-    /*
-    ** sqlite3_test_control(FAULT_FAILURES, fault_id)
-    **
-    ** Return the number of faults (both hard and benign faults) that have
-    ** occurred since the injector identified by fault_id) was last configured.
-    */
-    case SQLITE_TESTCTRL_FAULT_FAILURES: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultFailures(id);
-      break;
-    }
+  for (i=0 ; i < nString ; ++i) {
+    if( pString[i]!=NULL ) sqlite3_free((void *) pString[i]);
+  }
+  sqlite3_free((void *) pString);
+}
 
-    /*
-    ** sqlite3_test_control(FAULT_BENIGN_FAILURES, fault_id)
-    **
-    ** Return the number of benign faults that have occurred since the
-    ** injector identified by fault_id was last configured.
-    */
-    case SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultBenignFailures(id);
-      break;
-    }
+/* select * from %_content where docid = [iDocid]
+ * The caller must delete the returned array and all strings in it.
+ * null fields will be NULL in the returned array.
+ *
+ * TODO: Perhaps we should return pointer/length strings here for consistency
+ * with other code which uses pointer/length. */
+static int content_select(fulltext_vtab *v, sqlite_int64 iDocid,
+                          const char ***pValues){
+  sqlite3_stmt *s;
+  const char **values;
+  int i;
+  int rc;
 
-    /*
-    ** sqlite3_test_control(FAULT_PENDING, fault_id)
-    **
-    ** Return the number of successes that will occur before the next
-    ** scheduled failure on fault injector fault_id.
-    ** If no failures are scheduled, return -1.
-    */
-    case SQLITE_TESTCTRL_FAULT_PENDING: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultPending(id);
-      break;
-    }
+  *pValues = NULL;
 
-    /*
-    ** Save the current state of the PRNG.
-    */
-    case SQLITE_TESTCTRL_PRNG_SAVE: {
-      sqlite3PrngSaveState();
-      break;
-    }
+  rc = sql_get_statement(v, CONTENT_SELECT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-    /*
-    ** Restore the state of the PRNG to the last state saved using
-    ** PRNG_SAVE.  If PRNG_SAVE has never before been called, then
-    ** this verb acts like PRNG_RESET.
-    */
-    case SQLITE_TESTCTRL_PRNG_RESTORE: {
-      sqlite3PrngRestoreState();
-      break;
-    }
+  rc = sqlite3_bind_int64(s, 1, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
 
-    /*
-    ** Reset the PRNG back to its uninitialized state.  The next call
-    ** to sqlite3_randomness() will reseed the PRNG using a single call
-    ** to the xRandomness method of the default VFS.
-    */
-    case SQLITE_TESTCTRL_PRNG_RESET: {
-      sqlite3PrngResetState();
-      break;
-    }
+  rc = sqlite3_step(s);
+  if( rc!=SQLITE_ROW ) return rc;
 
-    /*
-    **  sqlite3_test_control(BITVEC_TEST, size, program)
-    **
-    ** Run a test against a Bitvec object of size.  The program argument
-    ** is an array of integers that defines the test.  Return -1 on a
-    ** memory allocation error, 0 on success, or non-zero for an error.
-    ** See the sqlite3BitvecBuiltinTest() for additional information.
-    */
-    case SQLITE_TESTCTRL_BITVEC_TEST: {
-      int sz = va_arg(ap, int);
-      int *aProg = va_arg(ap, int*);
-      rc = sqlite3BitvecBuiltinTest(sz, aProg);
-      break;
+  values = (const char **) sqlite3_malloc(v->nColumn * sizeof(const char *));
+  for(i=0; i<v->nColumn; ++i){
+    if( sqlite3_column_type(s, i)==SQLITE_NULL ){
+      values[i] = NULL;
+    }else{
+      values[i] = string_dup((char*)sqlite3_column_text(s, i));
     }
   }
-  va_end(ap);
-#endif /* SQLITE_OMIT_BUILTIN_TEST */
-  return rc;
-}
-
-/************** End of main.c ************************************************/
-/************** Begin file fts3.c ********************************************/
-/*
-** 2006 Oct 10
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This is an SQLite module implementing full-text search.
-*/
 
-/*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
-*/
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ){
+    *pValues = values;
+    return SQLITE_OK;
+  }
 
-/* TODO(shess) Consider exporting this comment to an HTML file or the
-** wiki.
-*/
-/* The full-text index is stored in a series of b+tree (-like)
-** structures called segments which map terms to doclists.  The
-** structures are like b+trees in layout, but are constructed from the
-** bottom up in optimal fashion and are not updatable.  Since trees
-** are built from the bottom up, things will be described from the
-** bottom up.
-**
-**
-**** Varints ****
-** The basic unit of encoding is a variable-length integer called a
-** varint.  We encode variable-length integers in little-endian order
-** using seven bits * per byte as follows:
-**
-** KEY:
-**         A = 0xxxxxxx    7 bits of data and one flag bit
-**         B = 1xxxxxxx    7 bits of data and one flag bit
-**
-**  7 bits - A
-** 14 bits - BA
-** 21 bits - BBA
-** and so on.
-**
-** This is identical to how sqlite encodes varints (see util.c).
-**
-**
-**** Document lists ****
-** A doclist (document list) holds a docid-sorted list of hits for a
-** given term.  Doclists hold docids, and can optionally associate
-** token positions and offsets with docids.
-**
-** A DL_POSITIONS_OFFSETS doclist is stored like this:
-**
-** array {
-**   varint docid;
-**   array {                (position list for column 0)
-**     varint position;     (delta from previous position plus POS_BASE)
-**     varint startOffset;  (delta from previous startOffset)
-**     varint endOffset;    (delta from startOffset)
-**   }
-**   array {
-**     varint POS_COLUMN;   (marks start of position list for new column)
-**     varint column;       (index of new column)
-**     array {
-**       varint position;   (delta from previous position plus POS_BASE)
-**       varint startOffset;(delta from previous startOffset)
-**       varint endOffset;  (delta from startOffset)
-**     }
-**   }
-**   varint POS_END;        (marks end of positions for this document.
-** }
-**
-** Here, array { X } means zero or more occurrences of X, adjacent in
-** memory.  A "position" is an index of a token in the token stream
-** generated by the tokenizer, while an "offset" is a byte offset,
-** both based at 0.  Note that POS_END and POS_COLUMN occur in the
-** same logical place as the position element, and act as sentinals
-** ending a position list array.
-**
-** A DL_POSITIONS doclist omits the startOffset and endOffset
-** information.  A DL_DOCIDS doclist omits both the position and
-** offset information, becoming an array of varint-encoded docids.
-**
-** On-disk data is stored as type DL_DEFAULT, so we don't serialize
-** the type.  Due to how deletion is implemented in the segmentation
-** system, on-disk doclists MUST store at least positions.
-**
-**
-**** Segment leaf nodes ****
-** Segment leaf nodes store terms and doclists, ordered by term.  Leaf
-** nodes are written using LeafWriter, and read using LeafReader (to
-** iterate through a single leaf node's data) and LeavesReader (to
-** iterate through a segment's entire leaf layer).  Leaf nodes have
-** the format:
-**
-** varint iHeight;             (height from leaf level, always 0)
-** varint nTerm;               (length of first term)
-** char pTerm[nTerm];          (content of first term)
-** varint nDoclist;            (length of term's associated doclist)
-** char pDoclist[nDoclist];    (content of doclist)
-** array {
-**                             (further terms are delta-encoded)
-**   varint nPrefix;           (length of prefix shared with previous term)
-**   varint nSuffix;           (length of unshared suffix)
-**   char pTermSuffix[nSuffix];(unshared suffix of next term)
-**   varint nDoclist;          (length of term's associated doclist)
-**   char pDoclist[nDoclist];  (content of doclist)
-** }
-**
-** Here, array { X } means zero or more occurrences of X, adjacent in
-** memory.
-**
-** Leaf nodes are broken into blocks which are stored contiguously in
-** the %_segments table in sorted order.  This means that when the end
-** of a node is reached, the next term is in the node with the next
-** greater node id.
-**
-** New data is spilled to a new leaf node when the current node
-** exceeds LEAF_MAX bytes (default 2048).  New data which itself is
-** larger than STANDALONE_MIN (default 1024) is placed in a standalone
-** node (a leaf node with a single term and doclist).  The goal of
-** these settings is to pack together groups of small doclists while
-** making it efficient to directly access large doclists.  The
-** assumption is that large doclists represent terms which are more
-** likely to be query targets.
-**
-** TODO(shess) It may be useful for blocking decisions to be more
-** dynamic.  For instance, it may make more sense to have a 2.5k leaf
-** node rather than splitting into 2k and .5k nodes.  My intuition is
-** that this might extend through 2x or 4x the pagesize.
-**
-**
-**** Segment interior nodes ****
-** Segment interior nodes store blockids for subtree nodes and terms
-** to describe what data is stored by the each subtree.  Interior
-** nodes are written using InteriorWriter, and read using
-** InteriorReader.  InteriorWriters are created as needed when
-** SegmentWriter creates new leaf nodes, or when an interior node
-** itself grows too big and must be split.  The format of interior
-** nodes:
-**
-** varint iHeight;           (height from leaf level, always >0)
-** varint iBlockid;          (block id of node's leftmost subtree)
-** optional {
-**   varint nTerm;           (length of first term)
-**   char pTerm[nTerm];      (content of first term)
-**   array {
-**                                (further terms are delta-encoded)
-**     varint nPrefix;            (length of shared prefix with previous term)
-**     varint nSuffix;            (length of unshared suffix)
-**     char pTermSuffix[nSuffix]; (unshared suffix of next term)
-**   }
-** }
-**
-** Here, optional { X } means an optional element, while array { X }
-** means zero or more occurrences of X, adjacent in memory.
-**
-** An interior node encodes n terms separating n+1 subtrees.  The
-** subtree blocks are contiguous, so only the first subtree's blockid
-** is encoded.  The subtree at iBlockid will contain all terms less
-** than the first term encoded (or all terms if no term is encoded).
-** Otherwise, for terms greater than or equal to pTerm[i] but less
-** than pTerm[i+1], the subtree for that term will be rooted at
-** iBlockid+i.  Interior nodes only store enough term data to
-** distinguish adjacent children (if the rightmost term of the left
-** child is "something", and the leftmost term of the right child is
-** "wicked", only "w" is stored).
-**
-** New data is spilled to a new interior node at the same height when
-** the current node exceeds INTERIOR_MAX bytes (default 2048).
-** INTERIOR_MIN_TERMS (default 7) keeps large terms from monopolizing
-** interior nodes and making the tree too skinny.  The interior nodes
-** at a given height are naturally tracked by interior nodes at
-** height+1, and so on.
-**
-**
-**** Segment directory ****
-** The segment directory in table %_segdir stores meta-information for
-** merging and deleting segments, and also the root node of the
-** segment's tree.
-**
-** The root node is the top node of the segment's tree after encoding
-** the entire segment, restricted to ROOT_MAX bytes (default 1024).
-** This could be either a leaf node or an interior node.  If the top
-** node requires more than ROOT_MAX bytes, it is flushed to %_segments
-** and a new root interior node is generated (which should always fit
-** within ROOT_MAX because it only needs space for 2 varints, the
-** height and the blockid of the previous root).
-**
-** The meta-information in the segment directory is:
-**   level               - segment level (see below)
-**   idx                 - index within level
-**                       - (level,idx uniquely identify a segment)
-**   start_block         - first leaf node
-**   leaves_end_block    - last leaf node
-**   end_block           - last block (including interior nodes)
-**   root                - contents of root node
-**
-** If the root node is a leaf node, then start_block,
-** leaves_end_block, and end_block are all 0.
-**
-**
-**** Segment merging ****
-** To amortize update costs, segments are groups into levels and
-** merged in matches.  Each increase in level represents exponentially
-** more documents.
-**
-** New documents (actually, document updates) are tokenized and
-** written individually (using LeafWriter) to a level 0 segment, with
-** incrementing idx.  When idx reaches MERGE_COUNT (default 16), all
-** level 0 segments are merged into a single level 1 segment.  Level 1
-** is populated like level 0, and eventually MERGE_COUNT level 1
-** segments are merged to a single level 2 segment (representing
-** MERGE_COUNT^2 updates), and so on.
-**
-** A segment merge traverses all segments at a given level in
-** parallel, performing a straightforward sorted merge.  Since segment
-** leaf nodes are written in to the %_segments table in order, this
-** merge traverses the underlying sqlite disk structures efficiently.
-** After the merge, all segment blocks from the merged level are
-** deleted.
-**
-** MERGE_COUNT controls how often we merge segments.  16 seems to be
-** somewhat of a sweet spot for insertion performance.  32 and 64 show
-** very similar performance numbers to 16 on insertion, though they're
-** a tiny bit slower (perhaps due to more overhead in merge-time
-** sorting).  8 is about 20% slower than 16, 4 about 50% slower than
-** 16, 2 about 66% slower than 16.
-**
-** At query time, high MERGE_COUNT increases the number of segments
-** which need to be scanned and merged.  For instance, with 100k docs
-** inserted:
-**
-**    MERGE_COUNT   segments
-**       16           25
-**        8           12
-**        4           10
-**        2            6
-**
-** This appears to have only a moderate impact on queries for very
-** frequent terms (which are somewhat dominated by segment merge
-** costs), and infrequent and non-existent terms still seem to be fast
-** even with many segments.
-**
-** TODO(shess) That said, it would be nice to have a better query-side
-** argument for MERGE_COUNT of 16.  Also, it is possible/likely that
-** optimizations to things like doclist merging will swing the sweet
-** spot around.
-**
-**
-**
-**** Handling of deletions and updates ****
-** Since we're using a segmented structure, with no docid-oriented
-** index into the term index, we clearly cannot simply update the term
-** index when a document is deleted or updated.  For deletions, we
-** write an empty doclist (varint(docid) varint(POS_END)), for updates
-** we simply write the new doclist.  Segment merges overwrite older
-** data for a particular docid with newer data, so deletes or updates
-** will eventually overtake the earlier data and knock it out.  The
-** query logic likewise merges doclists so that newer data knocks out
-** older data.
-**
-** TODO(shess) Provide a VACUUM type operation to clear out all
-** deletions and duplications.  This would basically be a forced merge
-** into a single segment.
+  freeStringArray(v->nColumn, values);
+  return rc;
+}
+
+/* delete from %_content where docid = [iDocid ] */
+static int content_delete(fulltext_vtab *v, sqlite_int64 iDocid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, CONTENT_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 1, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Returns SQLITE_ROW if any rows exist in %_content, SQLITE_DONE if
+** no rows exist, and any error in case of failure.
 */
+static int content_exists(fulltext_vtab *v){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, CONTENT_EXISTS_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+  rc = sqlite3_step(s);
+  if( rc!=SQLITE_ROW ) return rc;
 
-#if defined(SQLITE_ENABLE_FTS3) && !defined(SQLITE_CORE)
-# define SQLITE_CORE 1
-#endif
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_ROW;
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  return rc;
+}
+
+/* insert into %_segments values ([pData])
+**   returns assigned blockid in *piBlockid
+*/
+static int block_insert(fulltext_vtab *v, const char *pData, int nData,
+                        sqlite_int64 *piBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, BLOCK_INSERT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
+  rc = sqlite3_bind_blob(s, 1, pData, nData, SQLITE_STATIC);
+  if( rc!=SQLITE_OK ) return rc;
 
-/************** Include fts3_hash.h in the middle of fts3.c ******************/
-/************** Begin file fts3_hash.h ***************************************/
-/*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the header file for the generic hash-table implemenation
-** used in SQLite.  We've modified it slightly to serve as a standalone
-** hash table implementation for the full-text indexing module.
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+
+  /* blockid column is an alias for rowid. */
+  *piBlockid = sqlite3_last_insert_rowid(v->db);
+  return SQLITE_OK;
+}
+
+/* delete from %_segments
+**   where blockid between [iStartBlockid] and [iEndBlockid]
 **
+** Deletes the range of blocks, inclusive, used to delete the blocks
+** which form a segment.
 */
-#ifndef _FTS3_HASH_H_
-#define _FTS3_HASH_H_
+static int block_delete(fulltext_vtab *v,
+                        sqlite_int64 iStartBlockid, sqlite_int64 iEndBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, BLOCK_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* Forward declarations of structures. */
-typedef struct fts3Hash fts3Hash;
-typedef struct fts3HashElem fts3HashElem;
+  rc = sqlite3_bind_int64(s, 1, iStartBlockid);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* A complete hash table is an instance of the following structure.
-** The internals of this structure are intended to be opaque -- client
-** code should not attempt to access or modify the fields of this structure
-** directly.  Change this structure only by using the routines below.
-** However, many of the "procedures" and "functions" for modifying and
-** accessing this structure are really macros, so we can't really make
-** this structure opaque.
+  rc = sqlite3_bind_int64(s, 2, iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Returns SQLITE_ROW with *pidx set to the maximum segment idx found
+** at iLevel.  Returns SQLITE_DONE if there are no segments at
+** iLevel.  Otherwise returns an error.
 */
-struct fts3Hash {
-  char keyClass;          /* HASH_INT, _POINTER, _STRING, _BINARY */
-  char copyKey;           /* True if copy of key made on insert */
-  int count;              /* Number of entries in this table */
-  fts3HashElem *first;    /* The first element of the array */
-  int htsize;             /* Number of buckets in the hash table */
-  struct _fts3ht {        /* the hash table */
-    int count;               /* Number of entries with this hash */
-    fts3HashElem *chain;     /* Pointer to first entry with this hash */
-  } *ht;
-};
+static int segdir_max_index(fulltext_vtab *v, int iLevel, int *pidx){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_MAX_INDEX_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* Each element in the hash table is an instance of the following 
-** structure.  All elements are stored on a single doubly-linked list.
-**
-** Again, this structure is intended to be opaque, but it can't really
-** be opaque because it is used by macros.
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  /* Should always get at least one row due to how max() works. */
+  if( rc==SQLITE_DONE ) return SQLITE_DONE;
+  if( rc!=SQLITE_ROW ) return rc;
+
+  /* NULL means that there were no inputs to max(). */
+  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
+    rc = sqlite3_step(s);
+    if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+    return rc;
+  }
+
+  *pidx = sqlite3_column_int(s, 0);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+  return SQLITE_ROW;
+}
+
+/* insert into %_segdir values (
+**   [iLevel], [idx],
+**   [iStartBlockid], [iLeavesEndBlockid], [iEndBlockid],
+**   [pRootData]
+** )
 */
-struct fts3HashElem {
-  fts3HashElem *next, *prev; /* Next and previous elements in the table */
-  void *data;                /* Data associated with this element */
-  void *pKey; int nKey;      /* Key associated with this element */
-};
+static int segdir_set(fulltext_vtab *v, int iLevel, int idx,
+                      sqlite_int64 iStartBlockid,
+                      sqlite_int64 iLeavesEndBlockid,
+                      sqlite_int64 iEndBlockid,
+                      const char *pRootData, int nRootData){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SET_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int(s, 2, idx);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 3, iStartBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 4, iLeavesEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 5, iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_blob(s, 6, pRootData, nRootData, SQLITE_STATIC);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Queries %_segdir for the block span of the segments in level
+** iLevel.  Returns SQLITE_DONE if there are no blocks for iLevel,
+** SQLITE_ROW if there are blocks, else an error.
+*/
+static int segdir_span(fulltext_vtab *v, int iLevel,
+                       sqlite_int64 *piStartBlockid,
+                       sqlite_int64 *piEndBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SPAN_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_DONE;  /* Should never happen */
+  if( rc!=SQLITE_ROW ) return rc;
+
+  /* This happens if all segments at this level are entirely inline. */
+  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
+    /* We expect only one row.  We must execute another sqlite3_step()
+     * to complete the iteration; otherwise the table will remain locked. */
+    int rc2 = sqlite3_step(s);
+    if( rc2==SQLITE_ROW ) return SQLITE_ERROR;
+    return rc2;
+  }
+
+  *piStartBlockid = sqlite3_column_int64(s, 0);
+  *piEndBlockid = sqlite3_column_int64(s, 1);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+  return SQLITE_ROW;
+}
+
+/* Delete the segment blocks and segment directory records for all
+** segments at iLevel.
+*/
+static int segdir_delete(fulltext_vtab *v, int iLevel){
+  sqlite3_stmt *s;
+  sqlite_int64 iStartBlockid, iEndBlockid;
+  int rc = segdir_span(v, iLevel, &iStartBlockid, &iEndBlockid);
+  if( rc!=SQLITE_ROW && rc!=SQLITE_DONE ) return rc;
+
+  if( rc==SQLITE_ROW ){
+    rc = block_delete(v, iStartBlockid, iEndBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  /* Delete the segment directory itself. */
+  rc = sql_get_statement(v, SEGDIR_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Delete entire fts index, SQLITE_OK on success, relevant error on
+** failure.
+*/
+static int segdir_delete_all(fulltext_vtab *v){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_DELETE_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sql_single_step(s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sql_get_statement(v, BLOCK_DELETE_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Returns SQLITE_OK with *pnSegments set to the number of entries in
+** %_segdir and *piMaxLevel set to the highest level which has a
+** segment.  Otherwise returns the SQLite error which caused failure.
+*/
+static int segdir_count(fulltext_vtab *v, int *pnSegments, int *piMaxLevel){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_COUNT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  /* TODO(shess): This case should not be possible?  Should stronger
+  ** measures be taken if it happens?
+  */
+  if( rc==SQLITE_DONE ){
+    *pnSegments = 0;
+    *piMaxLevel = 0;
+    return SQLITE_OK;
+  }
+  if( rc!=SQLITE_ROW ) return rc;
+
+  *pnSegments = sqlite3_column_int(s, 0);
+  *piMaxLevel = sqlite3_column_int(s, 1);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_OK;
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  return rc;
+}
+
+/* TODO(shess) clearPendingTerms() is far down the file because
+** writeZeroSegment() is far down the file because LeafWriter is far
+** down the file.  Consider refactoring the code to move the non-vtab
+** code above the vtab code so that we don't need this forward
+** reference.
+*/
+static int clearPendingTerms(fulltext_vtab *v);
 
 /*
-** There are 2 different modes of operation for a hash table:
-**
-**   FTS3_HASH_STRING        pKey points to a string that is nKey bytes long
-**                           (including the null-terminator, if any).  Case
-**                           is respected in comparisons.
+** Free the memory used to contain a fulltext_vtab structure.
+*/
+static void fulltext_vtab_destroy(fulltext_vtab *v){
+  int iStmt, i;
+
+  FTSTRACE(("FTS3 Destroy %p\n", v));
+  for( iStmt=0; iStmt<MAX_STMT; iStmt++ ){
+    if( v->pFulltextStatements[iStmt]!=NULL ){
+      sqlite3_finalize(v->pFulltextStatements[iStmt]);
+      v->pFulltextStatements[iStmt] = NULL;
+    }
+  }
+
+  for( i=0; i<MERGE_COUNT; i++ ){
+    if( v->pLeafSelectStmts[i]!=NULL ){
+      sqlite3_finalize(v->pLeafSelectStmts[i]);
+      v->pLeafSelectStmts[i] = NULL;
+    }
+  }
+
+  if( v->pTokenizer!=NULL ){
+    v->pTokenizer->pModule->xDestroy(v->pTokenizer);
+    v->pTokenizer = NULL;
+  }
+
+  clearPendingTerms(v);
+
+  sqlite3_free(v->azColumn);
+  for(i = 0; i < v->nColumn; ++i) {
+    sqlite3_free(v->azContentColumn[i]);
+  }
+  sqlite3_free(v->azContentColumn);
+  sqlite3_free(v);
+}
+
+/*
+** Token types for parsing the arguments to xConnect or xCreate.
+*/
+#define TOKEN_EOF         0    /* End of file */
+#define TOKEN_SPACE       1    /* Any kind of whitespace */
+#define TOKEN_ID          2    /* An identifier */
+#define TOKEN_STRING      3    /* A string literal */
+#define TOKEN_PUNCT       4    /* A single punctuation character */
+
+/*
+** If X is a character that can be used in an identifier then
+** ftsIdChar(X) will be true.  Otherwise it is false.
 **
-**   FTS3_HASH_BINARY        pKey points to binary data nKey bytes long. 
-**                           memcmp() is used to compare keys.
+** For ASCII, any character with the high-order bit set is
+** allowed in an identifier.  For 7-bit characters, 
+** isFtsIdChar[X] must be 1.
 **
-** A copy of the key is made if the copyKey parameter to fts3HashInit is 1.  
+** Ticket #1066.  the SQL standard does not allow '$' in the
+** middle of identfiers.  But many SQL implementations do. 
+** SQLite will allow '$' in identifiers for compatibility.
+** But the feature is undocumented.
 */
-#define FTS3_HASH_STRING    1
-#define FTS3_HASH_BINARY    2
+static const char isFtsIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* 2x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
+};
+#define ftsIdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && isFtsIdChar[c-0x20]))
+
 
 /*
-** Access routines.  To delete, insert a NULL pointer.
+** Return the length of the token that begins at z[0]. 
+** Store the token type in *tokenType before returning.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash*, int keytype, int copyKey);
-SQLITE_PRIVATE void *sqlite3Fts3HashInsert(fts3Hash*, const void *pKey, int nKey, void *pData);
-SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash*, const void *pKey, int nKey);
-SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash*);
+static int ftsGetToken(const char *z, int *tokenType){
+  int i, c;
+  switch( *z ){
+    case 0: {
+      *tokenType = TOKEN_EOF;
+      return 0;
+    }
+    case ' ': case '\t': case '\n': case '\f': case '\r': {
+      for(i=1; safe_isspace(z[i]); i++){}
+      *tokenType = TOKEN_SPACE;
+      return i;
+    }
+    case '`':
+    case '\'':
+    case '"': {
+      int delim = z[0];
+      for(i=1; (c=z[i])!=0; i++){
+        if( c==delim ){
+          if( z[i+1]==delim ){
+            i++;
+          }else{
+            break;
+          }
+        }
+      }
+      *tokenType = TOKEN_STRING;
+      return i + (c!=0);
+    }
+    case '[': {
+      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
+      *tokenType = TOKEN_ID;
+      return i;
+    }
+    default: {
+      if( !ftsIdChar(*z) ){
+        break;
+      }
+      for(i=1; ftsIdChar(z[i]); i++){}
+      *tokenType = TOKEN_ID;
+      return i;
+    }
+  }
+  *tokenType = TOKEN_PUNCT;
+  return 1;
+}
 
 /*
-** Shorthand for the functions above
+** A token extracted from a string is an instance of the following
+** structure.
 */
-#define fts3HashInit   sqlite3Fts3HashInit
-#define fts3HashInsert sqlite3Fts3HashInsert
-#define fts3HashFind   sqlite3Fts3HashFind
-#define fts3HashClear  sqlite3Fts3HashClear
+typedef struct FtsToken {
+  const char *z;       /* Pointer to token text.  Not '\000' terminated */
+  short int n;         /* Length of the token text in bytes. */
+} FtsToken;
 
 /*
-** Macros for looping over all elements of a hash table.  The idiom is
-** like this:
+** Given a input string (which is really one of the argv[] parameters
+** passed into xConnect or xCreate) split the string up into tokens.
+** Return an array of pointers to '\000' terminated strings, one string
+** for each non-whitespace token.
 **
-**   fts3Hash h;
-**   fts3HashElem *p;
-**   ...
-**   for(p=fts3HashFirst(&h); p; p=fts3HashNext(p)){
-**     SomeStructure *pData = fts3HashData(p);
-**     // do something with pData
-**   }
+** The returned array is terminated by a single NULL pointer.
+**
+** Space to hold the returned array is obtained from a single
+** malloc and should be freed by passing the return value to free().
+** The individual strings within the token list are all a part of
+** the single memory allocation and will all be freed at once.
 */
-#define fts3HashFirst(H)  ((H)->first)
-#define fts3HashNext(E)   ((E)->next)
-#define fts3HashData(E)   ((E)->data)
-#define fts3HashKey(E)    ((E)->pKey)
-#define fts3HashKeysize(E) ((E)->nKey)
+static char **tokenizeString(const char *z, int *pnToken){
+  int nToken = 0;
+  FtsToken *aToken = sqlite3_malloc( strlen(z) * sizeof(aToken[0]) );
+  int n = 1;
+  int e, i;
+  int totalSize = 0;
+  char **azToken;
+  char *zCopy;
+  while( n>0 ){
+    n = ftsGetToken(z, &e);
+    if( e!=TOKEN_SPACE ){
+      aToken[nToken].z = z;
+      aToken[nToken].n = n;
+      nToken++;
+      totalSize += n+1;
+    }
+    z += n;
+  }
+  azToken = (char**)sqlite3_malloc( nToken*sizeof(char*) + totalSize );
+  zCopy = (char*)&azToken[nToken];
+  nToken--;
+  for(i=0; i<nToken; i++){
+    azToken[i] = zCopy;
+    n = aToken[i].n;
+    memcpy(zCopy, aToken[i].z, n);
+    zCopy[n] = 0;
+    zCopy += n+1;
+  }
+  azToken[nToken] = 0;
+  sqlite3_free(aToken);
+  *pnToken = nToken;
+  return azToken;
+}
 
 /*
-** Number of entries in a hash table
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters.  The conversion is done in-place.  If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** Examples:
+**
+**     "abc"   becomes   abc
+**     'xyz'   becomes   xyz
+**     [pqr]   becomes   pqr
+**     `mno`   becomes   mno
 */
-#define fts3HashCount(H)  ((H)->count)
-
-#endif /* _FTS3_HASH_H_ */
+static void dequoteString(char *z){
+  int quote;
+  int i, j;
+  if( z==0 ) return;
+  quote = z[0];
+  switch( quote ){
+    case '\'':  break;
+    case '"':   break;
+    case '`':   break;                /* For MySQL compatibility */
+    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
+    default:    return;
+  }
+  for(i=1, j=0; z[i]; i++){
+    if( z[i]==quote ){
+      if( z[i+1]==quote ){
+        z[j++] = quote;
+        i++;
+      }else{
+        z[j++] = 0;
+        break;
+      }
+    }else{
+      z[j++] = z[i];
+    }
+  }
+}
 
-/************** End of fts3_hash.h *******************************************/
-/************** Continuing where we left off in fts3.c ***********************/
-/************** Include fts3_tokenizer.h in the middle of fts3.c *************/
-/************** Begin file fts3_tokenizer.h **********************************/
 /*
-** 2006 July 10
-**
-** The author disclaims copyright to this source code.
+** The input azIn is a NULL-terminated list of tokens.  Remove the first
+** token and all punctuation tokens.  Remove the quotes from
+** around string literal tokens.
 **
-*************************************************************************
-** Defines the interface to tokenizers used by fulltext-search.  There
-** are three basic components:
+** Example:
 **
-** sqlite3_tokenizer_module is a singleton defining the tokenizer
-** interface functions.  This is essentially the class structure for
-** tokenizers.
+**     input:      tokenize chinese ( 'simplifed' , 'mixed' )
+**     output:     chinese simplifed mixed
 **
-** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
-** including customization information defined at creation time.
+** Another example:
 **
-** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
-** tokens from a particular input.
+**     input:      delimiters ( '[' , ']' , '...' )
+**     output:     [ ] ...
 */
-#ifndef _FTS3_TOKENIZER_H_
-#define _FTS3_TOKENIZER_H_
+static void tokenListToIdList(char **azIn){
+  int i, j;
+  if( azIn ){
+    for(i=0, j=-1; azIn[i]; i++){
+      if( safe_isalnum(azIn[i][0]) || azIn[i][1] ){
+        dequoteString(azIn[i]);
+        if( j>=0 ){
+          azIn[j] = azIn[i];
+        }
+        j++;
+      }
+    }
+    azIn[j] = 0;
+  }
+}
 
-/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
-** If tokenizers are to be allowed to call sqlite3_*() functions, then
-** we will need a way to register the API consistently.
-*/
 
 /*
-** Structures used by the tokenizer interface. When a new tokenizer
-** implementation is registered, the caller provides a pointer to
-** an sqlite3_tokenizer_module containing pointers to the callback
-** functions that make up an implementation.
+** Find the first alphanumeric token in the string zIn.  Null-terminate
+** this token.  Remove any quotation marks.  And return a pointer to
+** the result.
+*/
+static char *firstToken(char *zIn, char **pzTail){
+  int n, ttype;
+  while(1){
+    n = ftsGetToken(zIn, &ttype);
+    if( ttype==TOKEN_SPACE ){
+      zIn += n;
+    }else if( ttype==TOKEN_EOF ){
+      *pzTail = zIn;
+      return 0;
+    }else{
+      zIn[n] = 0;
+      *pzTail = &zIn[1];
+      dequoteString(zIn);
+      return zIn;
+    }
+  }
+  /*NOTREACHED*/
+}
+
+/* Return true if...
 **
-** When an fts3 table is created, it passes any arguments passed to
-** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
-** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
-** implementation. The xCreate() function in turn returns an 
-** sqlite3_tokenizer structure representing the specific tokenizer to
-** be used for the fts3 table (customized by the tokenizer clause arguments).
+**   *  s begins with the string t, ignoring case
+**   *  s is longer than t
+**   *  The first character of s beyond t is not a alphanumeric
+** 
+** Ignore leading space in *s.
 **
-** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
-** method is called. It returns an sqlite3_tokenizer_cursor object
-** that may be used to tokenize a specific input buffer based on
-** the tokenization rules supplied by a specific sqlite3_tokenizer
-** object.
+** To put it another way, return true if the first token of
+** s[] is t[].
 */
-typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
-typedef struct sqlite3_tokenizer sqlite3_tokenizer;
-typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
+static int startsWith(const char *s, const char *t){
+  while( safe_isspace(*s) ){ s++; }
+  while( *t ){
+    if( safe_tolower(*s++)!=safe_tolower(*t++) ) return 0;
+  }
+  return *s!='_' && !safe_isalnum(*s);
+}
 
-struct sqlite3_tokenizer_module {
+/*
+** An instance of this structure defines the "spec" of a
+** full text index.  This structure is populated by parseSpec
+** and use by fulltextConnect and fulltextCreate.
+*/
+typedef struct TableSpec {
+  const char *zDb;         /* Logical database name */
+  const char *zName;       /* Name of the full-text index */
+  int nColumn;             /* Number of columns to be indexed */
+  char **azColumn;         /* Original names of columns to be indexed */
+  char **azContentColumn;  /* Column names for %_content */
+  char **azTokenizer;      /* Name of tokenizer and its arguments */
+} TableSpec;
 
-  /*
-  ** Structure version. Should always be set to 0.
-  */
-  int iVersion;
+/*
+** Reclaim all of the memory used by a TableSpec
+*/
+static void clearTableSpec(TableSpec *p) {
+  sqlite3_free(p->azColumn);
+  sqlite3_free(p->azContentColumn);
+  sqlite3_free(p->azTokenizer);
+}
 
-  /*
-  ** Create a new tokenizer. The values in the argv[] array are the
-  ** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
-  ** TABLE statement that created the fts3 table. For example, if
-  ** the following SQL is executed:
-  **
-  **   CREATE .. USING fts3( ... , tokenizer <tokenizer-name> arg1 arg2)
-  **
-  ** then argc is set to 2, and the argv[] array contains pointers
-  ** to the strings "arg1" and "arg2".
-  **
-  ** This method should return either SQLITE_OK (0), or an SQLite error 
-  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
-  ** to point at the newly created tokenizer structure. The generic
-  ** sqlite3_tokenizer.pModule variable should not be initialised by
-  ** this callback. The caller will do so.
-  */
-  int (*xCreate)(
-    int argc,                           /* Size of argv array */
-    const char *const*argv,             /* Tokenizer argument strings */
-    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
-  );
+/* Parse a CREATE VIRTUAL TABLE statement, which looks like this:
+ *
+ * CREATE VIRTUAL TABLE email
+ *        USING fts3(subject, body, tokenize mytokenizer(myarg))
+ *
+ * We return parsed information in a TableSpec structure.
+ * 
+ */
+static int parseSpec(TableSpec *pSpec, int argc, const char *const*argv,
+                     char**pzErr){
+  int i, n;
+  char *z, *zDummy;
+  char **azArg;
+  const char *zTokenizer = 0;    /* argv[] entry describing the tokenizer */
 
-  /*
-  ** Destroy an existing tokenizer. The fts3 module calls this method
-  ** exactly once for each successful call to xCreate().
+  assert( argc>=3 );
+  /* Current interface:
+  ** argv[0] - module name
+  ** argv[1] - database name
+  ** argv[2] - table name
+  ** argv[3..] - columns, optionally followed by tokenizer specification
+  **             and snippet delimiters specification.
   */
-  int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
 
-  /*
-  ** Create a tokenizer cursor to tokenize an input buffer. The caller
-  ** is responsible for ensuring that the input buffer remains valid
-  ** until the cursor is closed (using the xClose() method). 
+  /* Make a copy of the complete argv[][] array in a single allocation.
+  ** The argv[][] array is read-only and transient.  We can write to the
+  ** copy in order to modify things and the copy is persistent.
   */
-  int (*xOpen)(
-    sqlite3_tokenizer *pTokenizer,       /* Tokenizer object */
-    const char *pInput, int nBytes,      /* Input buffer */
-    sqlite3_tokenizer_cursor **ppCursor  /* OUT: Created tokenizer cursor */
-  );
+  CLEAR(pSpec);
+  for(i=n=0; i<argc; i++){
+    n += strlen(argv[i]) + 1;
+  }
+  azArg = sqlite3_malloc( sizeof(char*)*argc + n );
+  if( azArg==0 ){
+    return SQLITE_NOMEM;
+  }
+  z = (char*)&azArg[argc];
+  for(i=0; i<argc; i++){
+    azArg[i] = z;
+    strcpy(z, argv[i]);
+    z += strlen(z)+1;
+  }
 
-  /*
-  ** Destroy an existing tokenizer cursor. The fts3 module calls this 
-  ** method exactly once for each successful call to xOpen().
+  /* Identify the column names and the tokenizer and delimiter arguments
+  ** in the argv[][] array.
   */
-  int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
+  pSpec->zDb = azArg[1];
+  pSpec->zName = azArg[2];
+  pSpec->nColumn = 0;
+  pSpec->azColumn = azArg;
+  zTokenizer = "tokenize simple";
+  for(i=3; i<argc; ++i){
+    if( startsWith(azArg[i],"tokenize") ){
+      zTokenizer = azArg[i];
+    }else{
+      z = azArg[pSpec->nColumn] = firstToken(azArg[i], &zDummy);
+      pSpec->nColumn++;
+    }
+  }
+  if( pSpec->nColumn==0 ){
+    azArg[0] = "content";
+    pSpec->nColumn = 1;
+  }
 
   /*
-  ** Retrieve the next token from the tokenizer cursor pCursor. This
-  ** method should either return SQLITE_OK and set the values of the
-  ** "OUT" variables identified below, or SQLITE_DONE to indicate that
-  ** the end of the buffer has been reached, or an SQLite error code.
+  ** Construct the list of content column names.
   **
-  ** *ppToken should be set to point at a buffer containing the 
-  ** normalized version of the token (i.e. after any case-folding and/or
-  ** stemming has been performed). *pnBytes should be set to the length
-  ** of this buffer in bytes. The input text that generated the token is
-  ** identified by the byte offsets returned in *piStartOffset and
-  ** *piEndOffset.
+  ** Each content column name will be of the form cNNAAAA
+  ** where NN is the column number and AAAA is the sanitized
+  ** column name.  "sanitized" means that special characters are
+  ** converted to "_".  The cNN prefix guarantees that all column
+  ** names are unique.
   **
-  ** The buffer *ppToken is set to point at is managed by the tokenizer
-  ** implementation. It is only required to be valid until the next call
-  ** to xNext() or xClose(). 
+  ** The AAAA suffix is not strictly necessary.  It is included
+  ** for the convenience of people who might examine the generated
+  ** %_content table and wonder what the columns are used for.
   */
-  /* TODO(shess) current implementation requires pInput to be
-  ** nul-terminated.  This should either be fixed, or pInput/nBytes
-  ** should be converted to zInput.
+  pSpec->azContentColumn = sqlite3_malloc( pSpec->nColumn * sizeof(char *) );
+  if( pSpec->azContentColumn==0 ){
+    clearTableSpec(pSpec);
+    return SQLITE_NOMEM;
+  }
+  for(i=0; i<pSpec->nColumn; i++){
+    char *p;
+    pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]);
+    for (p = pSpec->azContentColumn[i]; *p ; ++p) {
+      if( !safe_isalnum(*p) ) *p = '_';
+    }
+  }
+
+  /*
+  ** Parse the tokenizer specification string.
   */
-  int (*xNext)(
-    sqlite3_tokenizer_cursor *pCursor,   /* Tokenizer cursor */
-    const char **ppToken, int *pnBytes,  /* OUT: Normalized text for token */
-    int *piStartOffset,  /* OUT: Byte offset of token in input buffer */
-    int *piEndOffset,    /* OUT: Byte offset of end of token in input buffer */
-    int *piPosition      /* OUT: Number of tokens returned before this one */
-  );
-};
+  pSpec->azTokenizer = tokenizeString(zTokenizer, &n);
+  tokenListToIdList(pSpec->azTokenizer);
 
-struct sqlite3_tokenizer {
-  const sqlite3_tokenizer_module *pModule;  /* The module for this tokenizer */
-  /* Tokenizer implementations will typically add additional fields */
-};
+  return SQLITE_OK;
+}
 
-struct sqlite3_tokenizer_cursor {
-  sqlite3_tokenizer *pTokenizer;       /* Tokenizer for this cursor. */
-  /* Tokenizer implementations will typically add additional fields */
-};
+/*
+** Generate a CREATE TABLE statement that describes the schema of
+** the virtual table.  Return a pointer to this schema string.
+**
+** Space is obtained from sqlite3_mprintf() and should be freed
+** using sqlite3_free().
+*/
+static char *fulltextSchema(
+  int nColumn,                  /* Number of columns */
+  const char *const* azColumn,  /* List of columns */
+  const char *zTableName        /* Name of the table */
+){
+  int i;
+  char *zSchema, *zNext;
+  const char *zSep = "(";
+  zSchema = sqlite3_mprintf("CREATE TABLE x");
+  for(i=0; i<nColumn; i++){
+    zNext = sqlite3_mprintf("%s%s%Q", zSchema, zSep, azColumn[i]);
+    sqlite3_free(zSchema);
+    zSchema = zNext;
+    zSep = ",";
+  }
+  zNext = sqlite3_mprintf("%s,%Q HIDDEN", zSchema, zTableName);
+  sqlite3_free(zSchema);
+  zSchema = zNext;
+  zNext = sqlite3_mprintf("%s,docid HIDDEN)", zSchema);
+  sqlite3_free(zSchema);
+  return zNext;
+}
 
-#endif /* _FTS3_TOKENIZER_H_ */
+/*
+** Build a new sqlite3_vtab structure that will describe the
+** fulltext index defined by spec.
+*/
+static int constructVtab(
+  sqlite3 *db,              /* The SQLite database connection */
+  fts3Hash *pHash,          /* Hash table containing tokenizers */
+  TableSpec *spec,          /* Parsed spec information from parseSpec() */
+  sqlite3_vtab **ppVTab,    /* Write the resulting vtab structure here */
+  char **pzErr              /* Write any error message here */
+){
+  int rc;
+  int n;
+  fulltext_vtab *v = 0;
+  const sqlite3_tokenizer_module *m = NULL;
+  char *schema;
 
-/************** End of fts3_tokenizer.h **************************************/
-/************** Continuing where we left off in fts3.c ***********************/
-#ifndef SQLITE_CORE 
-  SQLITE_EXTENSION_INIT1
-#endif
+  char const *zTok;         /* Name of tokenizer to use for this fts table */
+  int nTok;                 /* Length of zTok, including nul terminator */
 
+  v = (fulltext_vtab *) sqlite3_malloc(sizeof(fulltext_vtab));
+  if( v==0 ) return SQLITE_NOMEM;
+  CLEAR(v);
+  /* sqlite will initialize v->base */
+  v->db = db;
+  v->zDb = spec->zDb;       /* Freed when azColumn is freed */
+  v->zName = spec->zName;   /* Freed when azColumn is freed */
+  v->nColumn = spec->nColumn;
+  v->azContentColumn = spec->azContentColumn;
+  spec->azContentColumn = 0;
+  v->azColumn = spec->azColumn;
+  spec->azColumn = 0;
 
-/* TODO(shess) MAN, this thing needs some refactoring.  At minimum, it
-** would be nice to order the file better, perhaps something along the
-** lines of:
-**
-**  - utility functions
-**  - table setup functions
-**  - table update functions
-**  - table query functions
-**
-** Put the query functions last because they're likely to reference
-** typedefs or functions from the table update section.
-*/
+  if( spec->azTokenizer==0 ){
+    return SQLITE_NOMEM;
+  }
 
-#if 0
-# define FTSTRACE(A)  printf A; fflush(stdout)
-#else
-# define FTSTRACE(A)
-#endif
+  zTok = spec->azTokenizer[0]; 
+  if( !zTok ){
+    zTok = "simple";
+  }
+  nTok = strlen(zTok)+1;
 
-/*
-** Default span for NEAR operators.
-*/
-#define SQLITE_FTS3_DEFAULT_NEAR_PARAM 10
+  m = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zTok, nTok);
+  if( !m ){
+    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", spec->azTokenizer[0]);
+    rc = SQLITE_ERROR;
+    goto err;
+  }
 
-/* It is not safe to call isspace(), tolower(), or isalnum() on
-** hi-bit-set characters.  This is the same solution used in the
-** tokenizer.
-*/
-/* TODO(shess) The snippet-generation code should be using the
-** tokenizer-generated tokens rather than doing its own local
-** tokenization.
-*/
-/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
-static int safe_isspace(char c){
-  return (c&0x80)==0 ? isspace(c) : 0;
-}
-static int safe_tolower(char c){
-  return (c&0x80)==0 ? tolower(c) : c;
-}
-static int safe_isalnum(char c){
-  return (c&0x80)==0 ? isalnum(c) : 0;
+  for(n=0; spec->azTokenizer[n]; n++){}
+  if( n ){
+    rc = m->xCreate(n-1, (const char*const*)&spec->azTokenizer[1],
+                    &v->pTokenizer);
+  }else{
+    rc = m->xCreate(0, 0, &v->pTokenizer);
+  }
+  if( rc!=SQLITE_OK ) goto err;
+  v->pTokenizer->pModule = m;
+
+  /* TODO: verify the existence of backing tables foo_content, foo_term */
+
+  schema = fulltextSchema(v->nColumn, (const char*const*)v->azColumn,
+                          spec->zName);
+  rc = sqlite3_declare_vtab(db, schema);
+  sqlite3_free(schema);
+  if( rc!=SQLITE_OK ) goto err;
+
+  memset(v->pFulltextStatements, 0, sizeof(v->pFulltextStatements));
+
+  /* Indicate that the buffer is not live. */
+  v->nPendingData = -1;
+
+  *ppVTab = &v->base;
+  FTSTRACE(("FTS3 Connect %p\n", v));
+
+  return rc;
+
+err:
+  fulltext_vtab_destroy(v);
+  return rc;
 }
 
-typedef enum DocListType {
-  DL_DOCIDS,              /* docids only */
-  DL_POSITIONS,           /* docids + positions */
-  DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
-} DocListType;
+static int fulltextConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVTab,
+  char **pzErr
+){
+  TableSpec spec;
+  int rc = parseSpec(&spec, argc, argv, pzErr);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** By default, only positions and not offsets are stored in the doclists.
-** To change this so that offsets are stored too, compile with
-**
-**          -DDL_DEFAULT=DL_POSITIONS_OFFSETS
-**
-** If DL_DEFAULT is set to DL_DOCIDS, your table can only be inserted
-** into (no deletes or updates).
+  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
+  clearTableSpec(&spec);
+  return rc;
+}
+
+/* The %_content table holds the text of each document, with
+** the docid column exposed as the SQLite rowid for the table.
 */
-#ifndef DL_DEFAULT
-# define DL_DEFAULT DL_POSITIONS
-#endif
+/* TODO(shess) This comment needs elaboration to match the updated
+** code.  Work it into the top-of-file comment at that time.
+*/
+static int fulltextCreate(sqlite3 *db, void *pAux,
+                          int argc, const char * const *argv,
+                          sqlite3_vtab **ppVTab, char **pzErr){
+  int rc;
+  TableSpec spec;
+  StringBuffer schema;
+  FTSTRACE(("FTS3 Create\n"));
 
-enum {
-  POS_END = 0,        /* end of this position list */
-  POS_COLUMN,         /* followed by new column number */
-  POS_BASE
-};
+  rc = parseSpec(&spec, argc, argv, pzErr);
+  if( rc!=SQLITE_OK ) return rc;
+
+  initStringBuffer(&schema);
+  append(&schema, "CREATE TABLE %_content(");
+  append(&schema, "  docid INTEGER PRIMARY KEY,");
+  appendList(&schema, spec.nColumn, spec.azContentColumn);
+  append(&schema, ")");
+  rc = sql_exec(db, spec.zDb, spec.zName, stringBufferData(&schema));
+  stringBufferDestroy(&schema);
+  if( rc!=SQLITE_OK ) goto out;
+
+  rc = sql_exec(db, spec.zDb, spec.zName,
+                "create table %_segments("
+                "  blockid INTEGER PRIMARY KEY,"
+                "  block blob"
+                ");"
+                );
+  if( rc!=SQLITE_OK ) goto out;
+
+  rc = sql_exec(db, spec.zDb, spec.zName,
+                "create table %_segdir("
+                "  level integer,"
+                "  idx integer,"
+                "  start_block integer,"
+                "  leaves_end_block integer,"
+                "  end_block integer,"
+                "  root blob,"
+                "  primary key(level, idx)"
+                ");");
+  if( rc!=SQLITE_OK ) goto out;
 
-/* MERGE_COUNT controls how often we merge segments (see comment at
-** top of file).
-*/
-#define MERGE_COUNT 16
+  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
 
-/* utility functions */
+out:
+  clearTableSpec(&spec);
+  return rc;
+}
 
-/* CLEAR() and SCRAMBLE() abstract memset() on a pointer to a single
-** record to prevent errors of the form:
-**
-** my_function(SomeType *b){
-**   memset(b, '\0', sizeof(b));  // sizeof(b)!=sizeof(*b)
-** }
-*/
-/* TODO(shess) Obvious candidates for a header file. */
-#define CLEAR(b) memset(b, '\0', sizeof(*(b)))
+/* Decide how to handle an SQL query. */
+static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
+  fulltext_vtab *v = (fulltext_vtab *)pVTab;
+  int i;
+  FTSTRACE(("FTS3 BestIndex\n"));
 
-#ifndef NDEBUG
-#  define SCRAMBLE(b) memset(b, 0x55, sizeof(*(b)))
-#else
-#  define SCRAMBLE(b)
-#endif
+  for(i=0; i<pInfo->nConstraint; ++i){
+    const struct sqlite3_index_constraint *pConstraint;
+    pConstraint = &pInfo->aConstraint[i];
+    if( pConstraint->usable ) {
+      if( (pConstraint->iColumn==-1 || pConstraint->iColumn==v->nColumn+1) &&
+          pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+        pInfo->idxNum = QUERY_DOCID;      /* lookup by docid */
+        FTSTRACE(("FTS3 QUERY_DOCID\n"));
+      } else if( pConstraint->iColumn>=0 && pConstraint->iColumn<=v->nColumn &&
+                 pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
+        /* full-text search */
+        pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn;
+        FTSTRACE(("FTS3 QUERY_FULLTEXT %d\n", pConstraint->iColumn));
+      } else continue;
 
-/* We may need up to VARINT_MAX bytes to store an encoded 64-bit integer. */
-#define VARINT_MAX 10
+      pInfo->aConstraintUsage[i].argvIndex = 1;
+      pInfo->aConstraintUsage[i].omit = 1;
 
-/* Write a 64-bit variable-length integer to memory starting at p[0].
- * The length of data written will be between 1 and VARINT_MAX bytes.
- * The number of bytes written is returned. */
-static int fts3PutVarint(char *p, sqlite_int64 v){
-  unsigned char *q = (unsigned char *) p;
-  sqlite_uint64 vu = v;
-  do{
-    *q++ = (unsigned char) ((vu & 0x7f) | 0x80);
-    vu >>= 7;
-  }while( vu!=0 );
-  q[-1] &= 0x7f;  /* turn off high bit in final byte */
-  assert( q - (unsigned char *)p <= VARINT_MAX );
-  return (int) (q - (unsigned char *)p);
-}
+      /* An arbitrary value for now.
+       * TODO: Perhaps docid matches should be considered cheaper than
+       * full-text searches. */
+      pInfo->estimatedCost = 1.0;   
 
-/* Read a 64-bit variable-length integer from memory starting at p[0].
- * Return the number of bytes read, or 0 on error.
- * The value is stored in *v. */
-static int fts3GetVarint(const char *p, sqlite_int64 *v){
-  const unsigned char *q = (const unsigned char *) p;
-  sqlite_uint64 x = 0, y = 1;
-  while( (*q & 0x80) == 0x80 ){
-    x += y * (*q++ & 0x7f);
-    y <<= 7;
-    if( q - (unsigned char *)p >= VARINT_MAX ){  /* bad data */
-      assert( 0 );
-      return 0;
+      return SQLITE_OK;
     }
   }
-  x += y * (*q++);
-  *v = (sqlite_int64) x;
-  return (int) (q - (unsigned char *)p);
+  pInfo->idxNum = QUERY_GENERIC;
+  return SQLITE_OK;
 }
 
-static int fts3GetVarint32(const char *p, int *pi){
- sqlite_int64 i;
- int ret = fts3GetVarint(p, &i);
- *pi = (int) i;
- assert( *pi==i );
- return ret;
+static int fulltextDisconnect(sqlite3_vtab *pVTab){
+  FTSTRACE(("FTS3 Disconnect %p\n", pVTab));
+  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
+  return SQLITE_OK;
 }
 
-/*******************************************************************/
-/* DataBuffer is used to collect data into a buffer in piecemeal
-** fashion.  It implements the usual distinction between amount of
-** data currently stored (nData) and buffer capacity (nCapacity).
-**
-** dataBufferInit - create a buffer with given initial capacity.
-** dataBufferReset - forget buffer's data, retaining capacity.
-** dataBufferDestroy - free buffer's data.
-** dataBufferSwap - swap contents of two buffers.
-** dataBufferExpand - expand capacity without adding data.
-** dataBufferAppend - append data.
-** dataBufferAppend2 - append two pieces of data at once.
-** dataBufferReplace - replace buffer's data.
-*/
-typedef struct DataBuffer {
-  char *pData;          /* Pointer to malloc'ed buffer. */
-  int nCapacity;        /* Size of pData buffer. */
-  int nData;            /* End of data loaded into pData. */
-} DataBuffer;
-
-static void dataBufferInit(DataBuffer *pBuffer, int nCapacity){
-  assert( nCapacity>=0 );
-  pBuffer->nData = 0;
-  pBuffer->nCapacity = nCapacity;
-  pBuffer->pData = nCapacity==0 ? NULL : sqlite3_malloc(nCapacity);
-}
-static void dataBufferReset(DataBuffer *pBuffer){
-  pBuffer->nData = 0;
-}
-static void dataBufferDestroy(DataBuffer *pBuffer){
-  if( pBuffer->pData!=NULL ) sqlite3_free(pBuffer->pData);
-  SCRAMBLE(pBuffer);
-}
-static void dataBufferSwap(DataBuffer *pBuffer1, DataBuffer *pBuffer2){
-  DataBuffer tmp = *pBuffer1;
-  *pBuffer1 = *pBuffer2;
-  *pBuffer2 = tmp;
-}
-static void dataBufferExpand(DataBuffer *pBuffer, int nAddCapacity){
-  assert( nAddCapacity>0 );
-  /* TODO(shess) Consider expanding more aggressively.  Note that the
-  ** underlying malloc implementation may take care of such things for
-  ** us already.
-  */
-  if( pBuffer->nData+nAddCapacity>pBuffer->nCapacity ){
-    pBuffer->nCapacity = pBuffer->nData+nAddCapacity;
-    pBuffer->pData = sqlite3_realloc(pBuffer->pData, pBuffer->nCapacity);
-  }
-}
-static void dataBufferAppend(DataBuffer *pBuffer,
-                             const char *pSource, int nSource){
-  assert( nSource>0 && pSource!=NULL );
-  dataBufferExpand(pBuffer, nSource);
-  memcpy(pBuffer->pData+pBuffer->nData, pSource, nSource);
-  pBuffer->nData += nSource;
-}
-static void dataBufferAppend2(DataBuffer *pBuffer,
-                              const char *pSource1, int nSource1,
-                              const char *pSource2, int nSource2){
-  assert( nSource1>0 && pSource1!=NULL );
-  assert( nSource2>0 && pSource2!=NULL );
-  dataBufferExpand(pBuffer, nSource1+nSource2);
-  memcpy(pBuffer->pData+pBuffer->nData, pSource1, nSource1);
-  memcpy(pBuffer->pData+pBuffer->nData+nSource1, pSource2, nSource2);
-  pBuffer->nData += nSource1+nSource2;
-}
-static void dataBufferReplace(DataBuffer *pBuffer,
-                              const char *pSource, int nSource){
-  dataBufferReset(pBuffer);
-  dataBufferAppend(pBuffer, pSource, nSource);
-}
+static int fulltextDestroy(sqlite3_vtab *pVTab){
+  fulltext_vtab *v = (fulltext_vtab *)pVTab;
+  int rc;
 
-/* StringBuffer is a null-terminated version of DataBuffer. */
-typedef struct StringBuffer {
-  DataBuffer b;            /* Includes null terminator. */
-} StringBuffer;
+  FTSTRACE(("FTS3 Destroy %p\n", pVTab));
+  rc = sql_exec(v->db, v->zDb, v->zName,
+                "drop table if exists %_content;"
+                "drop table if exists %_segments;"
+                "drop table if exists %_segdir;"
+                );
+  if( rc!=SQLITE_OK ) return rc;
 
-static void initStringBuffer(StringBuffer *sb){
-  dataBufferInit(&sb->b, 100);
-  dataBufferReplace(&sb->b, "", 1);
-}
-static int stringBufferLength(StringBuffer *sb){
-  return sb->b.nData-1;
-}
-static char *stringBufferData(StringBuffer *sb){
-  return sb->b.pData;
-}
-static void stringBufferDestroy(StringBuffer *sb){
-  dataBufferDestroy(&sb->b);
+  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
+  return SQLITE_OK;
 }
 
-static void nappend(StringBuffer *sb, const char *zFrom, int nFrom){
-  assert( sb->b.nData>0 );
-  if( nFrom>0 ){
-    sb->b.nData--;
-    dataBufferAppend2(&sb->b, zFrom, nFrom, "", 1);
+static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  fulltext_cursor *c;
+
+  c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
+  if( c ){
+    memset(c, 0, sizeof(fulltext_cursor));
+    /* sqlite will initialize c->base */
+    *ppCursor = &c->base;
+    FTSTRACE(("FTS3 Open %p: %p\n", pVTab, c));
+    return SQLITE_OK;
+  }else{
+    return SQLITE_NOMEM;
   }
 }
-static void append(StringBuffer *sb, const char *zFrom){
-  nappend(sb, zFrom, strlen(zFrom));
+
+/* Free all of the dynamically allocated memory held by the
+** Snippet
+*/
+static void snippetClear(Snippet *p){
+  sqlite3_free(p->aMatch);
+  sqlite3_free(p->zOffset);
+  sqlite3_free(p->zSnippet);
+  CLEAR(p);
 }
 
-/* Append a list of strings separated by commas. */
-static void appendList(StringBuffer *sb, int nString, char **azString){
+/*
+** Append a single entry to the p->aMatch[] log.
+*/
+static void snippetAppendMatch(
+  Snippet *p,               /* Append the entry to this snippet */
+  int iCol, int iTerm,      /* The column and query term */
+  int iToken,               /* Matching token in document */
+  int iStart, int nByte     /* Offset and size of the match */
+){
   int i;
-  for(i=0; i<nString; ++i){
-    if( i>0 ) append(sb, ", ");
-    append(sb, azString[i]);
+  struct snippetMatch *pMatch;
+  if( p->nMatch+1>=p->nAlloc ){
+    p->nAlloc = p->nAlloc*2 + 10;
+    p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
+    if( p->aMatch==0 ){
+      p->nMatch = 0;
+      p->nAlloc = 0;
+      return;
+    }
   }
+  i = p->nMatch++;
+  pMatch = &p->aMatch[i];
+  pMatch->iCol = iCol;
+  pMatch->iTerm = iTerm;
+  pMatch->iToken = iToken;
+  pMatch->iStart = iStart;
+  pMatch->nByte = nByte;
 }
 
-static int endsInWhiteSpace(StringBuffer *p){
-  return stringBufferLength(p)>0 &&
-    safe_isspace(stringBufferData(p)[stringBufferLength(p)-1]);
+/*
+** Sizing information for the circular buffer used in snippetOffsetsOfColumn()
+*/
+#define FTS3_ROTOR_SZ   (32)
+#define FTS3_ROTOR_MASK (FTS3_ROTOR_SZ-1)
+
+/*
+** Function to iterate through the tokens of a compiled expression.
+**
+** Except, skip all tokens on the right-hand side of a NOT operator.
+** This function is used to find tokens as part of snippet and offset
+** generation and we do nt want snippets and offsets to report matches
+** for tokens on the RHS of a NOT.
+*/
+static int fts3NextExprToken(Fts3Expr **ppExpr, int *piToken){
+  Fts3Expr *p = *ppExpr;
+  int iToken = *piToken;
+  if( iToken<0 ){
+    /* In this case the expression p is the root of an expression tree.
+    ** Move to the first token in the expression tree.
+    */
+    while( p->pLeft ){
+      p = p->pLeft;
+    }
+    iToken = 0;
+  }else{
+    assert(p && p->eType==FTSQUERY_PHRASE );
+    if( iToken<(p->pPhrase->nToken-1) ){
+      iToken++;
+    }else{
+      iToken = 0;
+      while( p->pParent && p->pParent->pLeft!=p ){
+        assert( p->pParent->pRight==p );
+        p = p->pParent;
+      }
+      p = p->pParent;
+      if( p ){
+        assert( p->pRight!=0 );
+        p = p->pRight;
+        while( p->pLeft ){
+          p = p->pLeft;
+        }
+      }
+    }
+  }
+
+  *ppExpr = p;
+  *piToken = iToken;
+  return p?1:0;
 }
 
-/* If the StringBuffer ends in something other than white space, add a
-** single space character to the end.
+/*
+** Return TRUE if the expression node pExpr is located beneath the
+** RHS of a NOT operator.
 */
-static void appendWhiteSpace(StringBuffer *p){
-  if( stringBufferLength(p)==0 ) return;
-  if( !endsInWhiteSpace(p) ) append(p, " ");
+static int fts3ExprBeneathNot(Fts3Expr *p){
+  Fts3Expr *pParent;
+  while( p ){
+    pParent = p->pParent;
+    if( pParent && pParent->eType==FTSQUERY_NOT && pParent->pRight==p ){
+      return 1;
+    }
+    p = pParent;
+  }
+  return 0;
 }
 
-/* Remove white space from the end of the StringBuffer */
-static void trimWhiteSpace(StringBuffer *p){
-  while( endsInWhiteSpace(p) ){
-    p->b.pData[--p->b.nData-1] = '\0';
+/*
+** Add entries to pSnippet->aMatch[] for every match that occurs against
+** document zDoc[0..nDoc-1] which is stored in column iColumn.
+*/
+static void snippetOffsetsOfColumn(
+  fulltext_cursor *pCur,         /* The fulltest search cursor */
+  Snippet *pSnippet,             /* The Snippet object to be filled in */
+  int iColumn,                   /* Index of fulltext table column */
+  const char *zDoc,              /* Text of the fulltext table column */
+  int nDoc                       /* Length of zDoc in bytes */
+){
+  const sqlite3_tokenizer_module *pTModule;  /* The tokenizer module */
+  sqlite3_tokenizer *pTokenizer;             /* The specific tokenizer */
+  sqlite3_tokenizer_cursor *pTCursor;        /* Tokenizer cursor */
+  fulltext_vtab *pVtab;                /* The full text index */
+  int nColumn;                         /* Number of columns in the index */
+  int i, j;                            /* Loop counters */
+  int rc;                              /* Return code */
+  unsigned int match, prevMatch;       /* Phrase search bitmasks */
+  const char *zToken;                  /* Next token from the tokenizer */
+  int nToken;                          /* Size of zToken */
+  int iBegin, iEnd, iPos;              /* Offsets of beginning and end */
+
+  /* The following variables keep a circular buffer of the last
+  ** few tokens */
+  unsigned int iRotor = 0;             /* Index of current token */
+  int iRotorBegin[FTS3_ROTOR_SZ];      /* Beginning offset of token */
+  int iRotorLen[FTS3_ROTOR_SZ];        /* Length of token */
+
+  pVtab = cursor_vtab(pCur);
+  nColumn = pVtab->nColumn;
+  pTokenizer = pVtab->pTokenizer;
+  pTModule = pTokenizer->pModule;
+  rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor);
+  if( rc ) return;
+  pTCursor->pTokenizer = pTokenizer;
+
+  prevMatch = 0;
+  while( !pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos) ){
+    Fts3Expr *pIter = pCur->pExpr;
+    int iIter = -1;
+    iRotorBegin[iRotor&FTS3_ROTOR_MASK] = iBegin;
+    iRotorLen[iRotor&FTS3_ROTOR_MASK] = iEnd-iBegin;
+    match = 0;
+    for(i=0; i<(FTS3_ROTOR_SZ-1) && fts3NextExprToken(&pIter, &iIter); i++){
+      int nPhrase;                    /* Number of tokens in current phrase */
+      struct PhraseToken *pToken;     /* Current token */
+      int iCol;                       /* Column index */
+
+      if( fts3ExprBeneathNot(pIter) ) continue;
+      nPhrase = pIter->pPhrase->nToken;
+      pToken = &pIter->pPhrase->aToken[iIter];
+      iCol = pIter->pPhrase->iColumn;
+      if( iCol>=0 && iCol<nColumn && iCol!=iColumn ) continue;
+      if( pToken->n>nToken ) continue;
+      if( !pToken->isPrefix && pToken->n<nToken ) continue;
+      assert( pToken->n<=nToken );
+      if( memcmp(pToken->z, zToken, pToken->n) ) continue;
+      if( iIter>0 && (prevMatch & (1<<i))==0 ) continue;
+      match |= 1<<i;
+      if( i==(FTS3_ROTOR_SZ-2) || nPhrase==iIter+1 ){
+        for(j=nPhrase-1; j>=0; j--){
+          int k = (iRotor-j) & FTS3_ROTOR_MASK;
+          snippetAppendMatch(pSnippet, iColumn, i-j, iPos-j,
+                iRotorBegin[k], iRotorLen[k]);
+        }
+      }
+    }
+    prevMatch = match<<1;
+    iRotor++;
   }
+  pTModule->xClose(pTCursor);  
 }
 
-/*******************************************************************/
-/* DLReader is used to read document elements from a doclist.  The
-** current docid is cached, so dlrDocid() is fast.  DLReader does not
-** own the doclist buffer.
+/*
+** Remove entries from the pSnippet structure to account for the NEAR
+** operator. When this is called, pSnippet contains the list of token 
+** offsets produced by treating all NEAR operators as AND operators.
+** This function removes any entries that should not be present after
+** accounting for the NEAR restriction. For example, if the queried
+** document is:
 **
-** dlrAtEnd - true if there's no more data to read.
-** dlrDocid - docid of current document.
-** dlrDocData - doclist data for current document (including docid).
-** dlrDocDataBytes - length of same.
-** dlrAllDataBytes - length of all remaining data.
-** dlrPosData - position data for current document.
-** dlrPosDataLen - length of pos data for current document (incl POS_END).
-** dlrStep - step to current document.
-** dlrInit - initial for doclist of given type against given data.
-** dlrDestroy - clean up.
+**     "A B C D E A"
 **
-** Expected usage is something like:
+** and the query is:
+** 
+**     A NEAR/0 E
 **
-**   DLReader reader;
-**   dlrInit(&reader, pData, nData);
-**   while( !dlrAtEnd(&reader) ){
-**     // calls to dlrDocid() and kin.
-**     dlrStep(&reader);
-**   }
-**   dlrDestroy(&reader);
+** then when this function is called the Snippet contains token offsets
+** 0, 4 and 5. This function removes the "0" entry (because the first A
+** is not near enough to an E).
+**
+** When this function is called, the value pointed to by parameter piLeft is
+** the integer id of the left-most token in the expression tree headed by
+** pExpr. This function increments *piLeft by the total number of tokens
+** in the expression tree headed by pExpr.
+**
+** Return 1 if any trimming occurs.  Return 0 if no trimming is required.
 */
-typedef struct DLReader {
-  DocListType iType;
-  const char *pData;
-  int nData;
+static int trimSnippetOffsets(
+  Fts3Expr *pExpr,      /* The search expression */
+  Snippet *pSnippet,    /* The set of snippet offsets to be trimmed */
+  int *piLeft           /* Index of left-most token in pExpr */
+){
+  if( pExpr ){
+    if( trimSnippetOffsets(pExpr->pLeft, pSnippet, piLeft) ){
+      return 1;
+    }
 
-  sqlite_int64 iDocid;
-  int nElement;
-} DLReader;
+    switch( pExpr->eType ){
+      case FTSQUERY_PHRASE:
+        *piLeft += pExpr->pPhrase->nToken;
+        break;
+      case FTSQUERY_NEAR: {
+        /* The right-hand-side of a NEAR operator is always a phrase. The
+        ** left-hand-side is either a phrase or an expression tree that is 
+        ** itself headed by a NEAR operator. The following initializations
+        ** set local variable iLeft to the token number of the left-most
+        ** token in the right-hand phrase, and iRight to the right most
+        ** token in the same phrase. For example, if we had:
+        **
+        **     <col> MATCH '"abc def" NEAR/2 "ghi jkl"'
+        **
+        ** then iLeft will be set to 2 (token number of ghi) and nToken will
+        ** be set to 4.
+        */
+        Fts3Expr *pLeft = pExpr->pLeft;
+        Fts3Expr *pRight = pExpr->pRight;
+        int iLeft = *piLeft;
+        int nNear = pExpr->nNear;
+        int nToken = pRight->pPhrase->nToken;
+        int jj, ii;
+        if( pLeft->eType==FTSQUERY_NEAR ){
+          pLeft = pLeft->pRight;
+        }
+        assert( pRight->eType==FTSQUERY_PHRASE );
+        assert( pLeft->eType==FTSQUERY_PHRASE );
+        nToken += pLeft->pPhrase->nToken;
+
+        for(ii=0; ii<pSnippet->nMatch; ii++){
+          struct snippetMatch *p = &pSnippet->aMatch[ii];
+          if( p->iTerm==iLeft ){
+            int isOk = 0;
+            /* Snippet ii is an occurence of query term iLeft in the document.
+            ** It occurs at position (p->iToken) of the document. We now
+            ** search for an instance of token (iLeft-1) somewhere in the 
+            ** range (p->iToken - nNear)...(p->iToken + nNear + nToken) within 
+            ** the set of snippetMatch structures. If one is found, proceed. 
+            ** If one cannot be found, then remove snippets ii..(ii+N-1) 
+            ** from the matching snippets, where N is the number of tokens 
+            ** in phrase pRight->pPhrase.
+            */
+            for(jj=0; isOk==0 && jj<pSnippet->nMatch; jj++){
+              struct snippetMatch *p2 = &pSnippet->aMatch[jj];
+              if( p2->iTerm==(iLeft-1) ){
+                if( p2->iToken>=(p->iToken-nNear-1) 
+                 && p2->iToken<(p->iToken+nNear+nToken) 
+                ){
+                  isOk = 1;
+                }
+              }
+            }
+            if( !isOk ){
+              int kk;
+              for(kk=0; kk<pRight->pPhrase->nToken; kk++){
+                pSnippet->aMatch[kk+ii].iTerm = -2;
+              }
+              return 1;
+            }
+          }
+          if( p->iTerm==(iLeft-1) ){
+            int isOk = 0;
+            for(jj=0; isOk==0 && jj<pSnippet->nMatch; jj++){
+              struct snippetMatch *p2 = &pSnippet->aMatch[jj];
+              if( p2->iTerm==iLeft ){
+                if( p2->iToken<=(p->iToken+nNear+1) 
+                 && p2->iToken>(p->iToken-nNear-nToken) 
+                ){
+                  isOk = 1;
+                }
+              }
+            }
+            if( !isOk ){
+              int kk;
+              for(kk=0; kk<pLeft->pPhrase->nToken; kk++){
+                pSnippet->aMatch[ii-kk].iTerm = -2;
+              }
+              return 1;
+            }
+          }
+        }
+        break;
+      }
+    }
 
-static int dlrAtEnd(DLReader *pReader){
-  assert( pReader->nData>=0 );
-  return pReader->nData==0;
-}
-static sqlite_int64 dlrDocid(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->iDocid;
+    if( trimSnippetOffsets(pExpr->pRight, pSnippet, piLeft) ){
+      return 1;
+    }
+  }
+  return 0;
 }
-static const char *dlrDocData(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->pData;
+
+/*
+** Compute all offsets for the current row of the query.  
+** If the offsets have already been computed, this routine is a no-op.
+*/
+static void snippetAllOffsets(fulltext_cursor *p){
+  int nColumn;
+  int iColumn, i;
+  int iFirst, iLast;
+  int iTerm = 0;
+  fulltext_vtab *pFts = cursor_vtab(p);
+
+  if( p->snippet.nMatch || p->pExpr==0 ){
+    return;
+  }
+  nColumn = pFts->nColumn;
+  iColumn = (p->iCursorType - QUERY_FULLTEXT);
+  if( iColumn<0 || iColumn>=nColumn ){
+    /* Look for matches over all columns of the full-text index */
+    iFirst = 0;
+    iLast = nColumn-1;
+  }else{
+    /* Look for matches in the iColumn-th column of the index only */
+    iFirst = iColumn;
+    iLast = iColumn;
+  }
+  for(i=iFirst; i<=iLast; i++){
+    const char *zDoc;
+    int nDoc;
+    zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1);
+    nDoc = sqlite3_column_bytes(p->pStmt, i+1);
+    snippetOffsetsOfColumn(p, &p->snippet, i, zDoc, nDoc);
+  }
+
+  while( trimSnippetOffsets(p->pExpr, &p->snippet, &iTerm) ){
+    iTerm = 0;
+  }
 }
-static int dlrDocDataBytes(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nElement;
+
+/*
+** Convert the information in the aMatch[] array of the snippet
+** into the string zOffset[0..nOffset-1]. This string is used as
+** the return of the SQL offsets() function.
+*/
+static void snippetOffsetText(Snippet *p){
+  int i;
+  int cnt = 0;
+  StringBuffer sb;
+  char zBuf[200];
+  if( p->zOffset ) return;
+  initStringBuffer(&sb);
+  for(i=0; i<p->nMatch; i++){
+    struct snippetMatch *pMatch = &p->aMatch[i];
+    if( pMatch->iTerm>=0 ){
+      /* If snippetMatch.iTerm is less than 0, then the match was 
+      ** discarded as part of processing the NEAR operator (see the 
+      ** trimSnippetOffsetsForNear() function for details). Ignore 
+      ** it in this case
+      */
+      zBuf[0] = ' ';
+      sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d",
+          pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte);
+      append(&sb, zBuf);
+      cnt++;
+    }
+  }
+  p->zOffset = stringBufferData(&sb);
+  p->nOffset = stringBufferLength(&sb);
 }
-static int dlrAllDataBytes(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nData;
+
+/*
+** zDoc[0..nDoc-1] is phrase of text.  aMatch[0..nMatch-1] are a set
+** of matching words some of which might be in zDoc.  zDoc is column
+** number iCol.
+**
+** iBreak is suggested spot in zDoc where we could begin or end an
+** excerpt.  Return a value similar to iBreak but possibly adjusted
+** to be a little left or right so that the break point is better.
+*/
+static int wordBoundary(
+  int iBreak,                   /* The suggested break point */
+  const char *zDoc,             /* Document text */
+  int nDoc,                     /* Number of bytes in zDoc[] */
+  struct snippetMatch *aMatch,  /* Matching words */
+  int nMatch,                   /* Number of entries in aMatch[] */
+  int iCol                      /* The column number for zDoc[] */
+){
+  int i;
+  if( iBreak<=10 ){
+    return 0;
+  }
+  if( iBreak>=nDoc-10 ){
+    return nDoc;
+  }
+  for(i=0; i<nMatch && aMatch[i].iCol<iCol; i++){}
+  while( i<nMatch && aMatch[i].iStart+aMatch[i].nByte<iBreak ){ i++; }
+  if( i<nMatch ){
+    if( aMatch[i].iStart<iBreak+10 ){
+      return aMatch[i].iStart;
+    }
+    if( i>0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){
+      return aMatch[i-1].iStart;
+    }
+  }
+  for(i=1; i<=10; i++){
+    if( safe_isspace(zDoc[iBreak-i]) ){
+      return iBreak - i + 1;
+    }
+    if( safe_isspace(zDoc[iBreak+i]) ){
+      return iBreak + i + 1;
+    }
+  }
+  return iBreak;
 }
-/* TODO(shess) Consider adding a field to track iDocid varint length
-** to make these two functions faster.  This might matter (a tiny bit)
-** for queries.
+
+
+
+/*
+** Allowed values for Snippet.aMatch[].snStatus
 */
-static const char *dlrPosData(DLReader *pReader){
-  sqlite_int64 iDummy;
-  int n = fts3GetVarint(pReader->pData, &iDummy);
-  assert( !dlrAtEnd(pReader) );
-  return pReader->pData+n;
-}
-static int dlrPosDataLen(DLReader *pReader){
-  sqlite_int64 iDummy;
-  int n = fts3GetVarint(pReader->pData, &iDummy);
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nElement-n;
-}
-static void dlrStep(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
+#define SNIPPET_IGNORE  0   /* It is ok to omit this match from the snippet */
+#define SNIPPET_DESIRED 1   /* We want to include this match in the snippet */
 
-  /* Skip past current doclist element. */
-  assert( pReader->nElement<=pReader->nData );
-  pReader->pData += pReader->nElement;
-  pReader->nData -= pReader->nElement;
+/*
+** Generate the text of a snippet.
+*/
+static void snippetText(
+  fulltext_cursor *pCursor,   /* The cursor we need the snippet for */
+  const char *zStartMark,     /* Markup to appear before each match */
+  const char *zEndMark,       /* Markup to appear after each match */
+  const char *zEllipsis       /* Ellipsis mark */
+){
+  int i, j;
+  struct snippetMatch *aMatch;
+  int nMatch;
+  int nDesired;
+  StringBuffer sb;
+  int tailCol;
+  int tailOffset;
+  int iCol;
+  int nDoc;
+  const char *zDoc;
+  int iStart, iEnd;
+  int tailEllipsis = 0;
+  int iMatch;
+  
 
-  /* If there is more data, read the next doclist element. */
-  if( pReader->nData!=0 ){
-    sqlite_int64 iDocidDelta;
-    int iDummy, n = fts3GetVarint(pReader->pData, &iDocidDelta);
-    pReader->iDocid += iDocidDelta;
-    if( pReader->iType>=DL_POSITIONS ){
-      assert( n<pReader->nData );
-      while( 1 ){
-        n += fts3GetVarint32(pReader->pData+n, &iDummy);
-        assert( n<=pReader->nData );
-        if( iDummy==POS_END ) break;
-        if( iDummy==POS_COLUMN ){
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          assert( n<pReader->nData );
-        }else if( pReader->iType==DL_POSITIONS_OFFSETS ){
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          assert( n<pReader->nData );
-        }
+  sqlite3_free(pCursor->snippet.zSnippet);
+  pCursor->snippet.zSnippet = 0;
+  aMatch = pCursor->snippet.aMatch;
+  nMatch = pCursor->snippet.nMatch;
+  initStringBuffer(&sb);
+
+  for(i=0; i<nMatch; i++){
+    aMatch[i].snStatus = SNIPPET_IGNORE;
+  }
+  nDesired = 0;
+  for(i=0; i<FTS3_ROTOR_SZ; i++){
+    for(j=0; j<nMatch; j++){
+      if( aMatch[j].iTerm==i ){
+        aMatch[j].snStatus = SNIPPET_DESIRED;
+        nDesired++;
+        break;
       }
     }
-    pReader->nElement = n;
-    assert( pReader->nElement<=pReader->nData );
   }
-}
-static void dlrInit(DLReader *pReader, DocListType iType,
-                    const char *pData, int nData){
-  assert( pData!=NULL && nData!=0 );
-  pReader->iType = iType;
-  pReader->pData = pData;
-  pReader->nData = nData;
-  pReader->nElement = 0;
-  pReader->iDocid = 0;
-
-  /* Load the first element's data.  There must be a first element. */
-  dlrStep(pReader);
-}
-static void dlrDestroy(DLReader *pReader){
-  SCRAMBLE(pReader);
-}
 
-#ifndef NDEBUG
-/* Verify that the doclist can be validly decoded.  Also returns the
-** last docid found because it is convenient in other assertions for
-** DLWriter.
-*/
-static void docListValidate(DocListType iType, const char *pData, int nData,
-                            sqlite_int64 *pLastDocid){
-  sqlite_int64 iPrevDocid = 0;
-  assert( nData>0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
-  while( nData!=0 ){
-    sqlite_int64 iDocidDelta;
-    int n = fts3GetVarint(pData, &iDocidDelta);
-    iPrevDocid += iDocidDelta;
-    if( iType>DL_DOCIDS ){
-      int iDummy;
-      while( 1 ){
-        n += fts3GetVarint32(pData+n, &iDummy);
-        if( iDummy==POS_END ) break;
-        if( iDummy==POS_COLUMN ){
-          n += fts3GetVarint32(pData+n, &iDummy);
-        }else if( iType>DL_POSITIONS ){
-          n += fts3GetVarint32(pData+n, &iDummy);
-          n += fts3GetVarint32(pData+n, &iDummy);
+  iMatch = 0;
+  tailCol = -1;
+  tailOffset = 0;
+  for(i=0; i<nMatch && nDesired>0; i++){
+    if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue;
+    nDesired--;
+    iCol = aMatch[i].iCol;
+    zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1);
+    nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1);
+    iStart = aMatch[i].iStart - 40;
+    iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol);
+    if( iStart<=10 ){
+      iStart = 0;
+    }
+    if( iCol==tailCol && iStart<=tailOffset+20 ){
+      iStart = tailOffset;
+    }
+    if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){
+      trimWhiteSpace(&sb);
+      appendWhiteSpace(&sb);
+      append(&sb, zEllipsis);
+      appendWhiteSpace(&sb);
+    }
+    iEnd = aMatch[i].iStart + aMatch[i].nByte + 40;
+    iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol);
+    if( iEnd>=nDoc-10 ){
+      iEnd = nDoc;
+      tailEllipsis = 0;
+    }else{
+      tailEllipsis = 1;
+    }
+    while( iMatch<nMatch && aMatch[iMatch].iCol<iCol ){ iMatch++; }
+    while( iStart<iEnd ){
+      while( iMatch<nMatch && aMatch[iMatch].iStart<iStart
+             && aMatch[iMatch].iCol<=iCol ){
+        iMatch++;
+      }
+      if( iMatch<nMatch && aMatch[iMatch].iStart<iEnd
+             && aMatch[iMatch].iCol==iCol ){
+        nappend(&sb, &zDoc[iStart], aMatch[iMatch].iStart - iStart);
+        iStart = aMatch[iMatch].iStart;
+        append(&sb, zStartMark);
+        nappend(&sb, &zDoc[iStart], aMatch[iMatch].nByte);
+        append(&sb, zEndMark);
+        iStart += aMatch[iMatch].nByte;
+        for(j=iMatch+1; j<nMatch; j++){
+          if( aMatch[j].iTerm==aMatch[iMatch].iTerm
+              && aMatch[j].snStatus==SNIPPET_DESIRED ){
+            nDesired--;
+            aMatch[j].snStatus = SNIPPET_IGNORE;
+          }
         }
-        assert( n<=nData );
+      }else{
+        nappend(&sb, &zDoc[iStart], iEnd - iStart);
+        iStart = iEnd;
       }
     }
-    assert( n<=nData );
-    pData += n;
-    nData -= n;
+    tailCol = iCol;
+    tailOffset = iEnd;
   }
-  if( pLastDocid ) *pLastDocid = iPrevDocid;
+  trimWhiteSpace(&sb);
+  if( tailEllipsis ){
+    appendWhiteSpace(&sb);
+    append(&sb, zEllipsis);
+  }
+  pCursor->snippet.zSnippet = stringBufferData(&sb);
+  pCursor->snippet.nSnippet = stringBufferLength(&sb);
 }
-#define ASSERT_VALID_DOCLIST(i, p, n, o) docListValidate(i, p, n, o)
-#else
-#define ASSERT_VALID_DOCLIST(i, p, n, o) assert( 1 )
-#endif
 
-/*******************************************************************/
-/* DLWriter is used to write doclist data to a DataBuffer.  DLWriter
-** always appends to the buffer and does not own it.
-**
-** dlwInit - initialize to write a given type doclistto a buffer.
-** dlwDestroy - clear the writer's memory.  Does not free buffer.
-** dlwAppend - append raw doclist data to buffer.
-** dlwCopy - copy next doclist from reader to writer.
-** dlwAdd - construct doclist element and append to buffer.
-**    Only apply dlwAdd() to DL_DOCIDS doclists (else use PLWriter).
-*/
-typedef struct DLWriter {
-  DocListType iType;
-  DataBuffer *b;
-  sqlite_int64 iPrevDocid;
-#ifndef NDEBUG
-  int has_iPrevDocid;
-#endif
-} DLWriter;
 
-static void dlwInit(DLWriter *pWriter, DocListType iType, DataBuffer *b){
-  pWriter->b = b;
-  pWriter->iType = iType;
-  pWriter->iPrevDocid = 0;
-#ifndef NDEBUG
-  pWriter->has_iPrevDocid = 0;
-#endif
-}
-static void dlwDestroy(DLWriter *pWriter){
-  SCRAMBLE(pWriter);
-}
-/* iFirstDocid is the first docid in the doclist in pData.  It is
-** needed because pData may point within a larger doclist, in which
-** case the first item would be delta-encoded.
-**
-** iLastDocid is the final docid in the doclist in pData.  It is
-** needed to create the new iPrevDocid for future delta-encoding.  The
-** code could decode the passed doclist to recreate iLastDocid, but
-** the only current user (docListMerge) already has decoded this
-** information.
-*/
-/* TODO(shess) This has become just a helper for docListMerge.
-** Consider a refactor to make this cleaner.
+/*
+** Close the cursor.  For additional information see the documentation
+** on the xClose method of the virtual table interface.
 */
-static void dlwAppend(DLWriter *pWriter,
-                      const char *pData, int nData,
-                      sqlite_int64 iFirstDocid, sqlite_int64 iLastDocid){
-  sqlite_int64 iDocid = 0;
-  char c[VARINT_MAX];
-  int nFirstOld, nFirstNew;     /* Old and new varint len of first docid. */
-#ifndef NDEBUG
-  sqlite_int64 iLastDocidDelta;
-#endif
+static int fulltextClose(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  FTSTRACE(("FTS3 Close %p\n", c));
+  sqlite3_finalize(c->pStmt);
+  sqlite3Fts3ExprFree(c->pExpr);
+  snippetClear(&c->snippet);
+  if( c->result.nData!=0 ){
+    dlrDestroy(&c->reader);
+  }
+  dataBufferDestroy(&c->result);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
 
-  /* Recode the initial docid as delta from iPrevDocid. */
-  nFirstOld = fts3GetVarint(pData, &iDocid);
-  assert( nFirstOld<nData || (nFirstOld==nData && pWriter->iType==DL_DOCIDS) );
-  nFirstNew = fts3PutVarint(c, iFirstDocid-pWriter->iPrevDocid);
+static int fulltextNext(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  int rc;
 
-  /* Verify that the incoming doclist is valid AND that it ends with
-  ** the expected docid.  This is essential because we'll trust this
-  ** docid in future delta-encoding.
-  */
-  ASSERT_VALID_DOCLIST(pWriter->iType, pData, nData, &iLastDocidDelta);
-  assert( iLastDocid==iFirstDocid-iDocid+iLastDocidDelta );
+  FTSTRACE(("FTS3 Next %p\n", pCursor));
+  snippetClear(&c->snippet);
+  if( c->iCursorType < QUERY_FULLTEXT ){
+    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
+    rc = sqlite3_step(c->pStmt);
+    switch( rc ){
+      case SQLITE_ROW:
+        c->eof = 0;
+        return SQLITE_OK;
+      case SQLITE_DONE:
+        c->eof = 1;
+        return SQLITE_OK;
+      default:
+        c->eof = 1;
+        return rc;
+    }
+  } else {  /* full-text query */
+    rc = sqlite3_reset(c->pStmt);
+    if( rc!=SQLITE_OK ) return rc;
 
-  /* Append recoded initial docid and everything else.  Rest of docids
-  ** should have been delta-encoded from previous initial docid.
-  */
-  if( nFirstOld<nData ){
-    dataBufferAppend2(pWriter->b, c, nFirstNew,
-                      pData+nFirstOld, nData-nFirstOld);
-  }else{
-    dataBufferAppend(pWriter->b, c, nFirstNew);
+    if( c->result.nData==0 || dlrAtEnd(&c->reader) ){
+      c->eof = 1;
+      return SQLITE_OK;
+    }
+    rc = sqlite3_bind_int64(c->pStmt, 1, dlrDocid(&c->reader));
+    dlrStep(&c->reader);
+    if( rc!=SQLITE_OK ) return rc;
+    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
+    rc = sqlite3_step(c->pStmt);
+    if( rc==SQLITE_ROW ){   /* the case we expect */
+      c->eof = 0;
+      return SQLITE_OK;
+    }
+    /* an error occurred; abort */
+    return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
   }
-  pWriter->iPrevDocid = iLastDocid;
-}
-static void dlwCopy(DLWriter *pWriter, DLReader *pReader){
-  dlwAppend(pWriter, dlrDocData(pReader), dlrDocDataBytes(pReader),
-            dlrDocid(pReader), dlrDocid(pReader));
 }
-static void dlwAdd(DLWriter *pWriter, sqlite_int64 iDocid){
-  char c[VARINT_MAX];
-  int n = fts3PutVarint(c, iDocid-pWriter->iPrevDocid);
 
-  /* Docids must ascend. */
-  assert( !pWriter->has_iPrevDocid || iDocid>pWriter->iPrevDocid );
-  assert( pWriter->iType==DL_DOCIDS );
 
-  dataBufferAppend(pWriter->b, c, n);
-  pWriter->iPrevDocid = iDocid;
-#ifndef NDEBUG
-  pWriter->has_iPrevDocid = 1;
-#endif
-}
+/* TODO(shess) If we pushed LeafReader to the top of the file, or to
+** another file, term_select() could be pushed above
+** docListOfTerm().
+*/
+static int termSelect(fulltext_vtab *v, int iColumn,
+                      const char *pTerm, int nTerm, int isPrefix,
+                      DocListType iType, DataBuffer *out);
 
-/*******************************************************************/
-/* PLReader is used to read data from a document's position list.  As
-** the caller steps through the list, data is cached so that varints
-** only need to be decoded once.
+/* 
+** Return a DocList corresponding to the phrase *pPhrase.
 **
-** plrInit, plrDestroy - create/destroy a reader.
-** plrColumn, plrPosition, plrStartOffset, plrEndOffset - accessors
-** plrAtEnd - at end of stream, only call plrDestroy once true.
-** plrStep - step to the next element.
+** The resulting DL_DOCIDS doclist is stored in pResult, which is
+** overwritten.
 */
-typedef struct PLReader {
-  /* These refer to the next position's data.  nData will reach 0 when
-  ** reading the last position, so plrStep() signals EOF by setting
-  ** pData to NULL.
-  */
-  const char *pData;
-  int nData;
+static int docListOfPhrase(
+  fulltext_vtab *pTab,   /* The full text index */
+  Fts3Phrase *pPhrase,   /* Phrase to return a doclist corresponding to */
+  DocListType eListType, /* Either DL_DOCIDS or DL_POSITIONS */
+  DataBuffer *pResult    /* Write the result here */
+){
+  int ii;
+  int rc = SQLITE_OK;
+  int iCol = pPhrase->iColumn;
+  DocListType eType = eListType;
+  assert( eType==DL_POSITIONS || eType==DL_DOCIDS );
+  if( pPhrase->nToken>1 ){
+    eType = DL_POSITIONS;
+  }
 
-  DocListType iType;
-  int iColumn;         /* the last column read */
-  int iPosition;       /* the last position read */
-  int iStartOffset;    /* the last start offset read */
-  int iEndOffset;      /* the last end offset read */
-} PLReader;
+  /* This code should never be called with buffered updates. */
+  assert( pTab->nPendingData<0 );
 
-static int plrAtEnd(PLReader *pReader){
-  return pReader->pData==NULL;
-}
-static int plrColumn(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iColumn;
-}
-static int plrPosition(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iPosition;
-}
-static int plrStartOffset(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iStartOffset;
-}
-static int plrEndOffset(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iEndOffset;
+  for(ii=0; rc==SQLITE_OK && ii<pPhrase->nToken; ii++){
+    DataBuffer tmp;
+    struct PhraseToken *p = &pPhrase->aToken[ii];
+    rc = termSelect(pTab, iCol, p->z, p->n, p->isPrefix, eType, &tmp);
+    if( rc==SQLITE_OK ){
+      if( ii==0 ){
+        *pResult = tmp;
+      }else{
+        DataBuffer res = *pResult;
+        dataBufferInit(pResult, 0);
+        if( ii==(pPhrase->nToken-1) ){
+          eType = eListType;
+        }
+        docListPhraseMerge(
+          res.pData, res.nData, tmp.pData, tmp.nData, 0, 0, eType, pResult
+        );
+        dataBufferDestroy(&res);
+        dataBufferDestroy(&tmp);
+      }
+    }
+  }
+
+  return rc;
 }
-static void plrStep(PLReader *pReader){
-  int i, n;
 
-  assert( !plrAtEnd(pReader) );
+/*
+** Evaluate the full-text expression pExpr against fts3 table pTab. Write
+** the results into pRes.
+*/
+static int evalFts3Expr(
+  fulltext_vtab *pTab,           /* Fts3 Virtual table object */
+  Fts3Expr *pExpr,               /* Parsed fts3 expression */
+  DataBuffer *pRes               /* OUT: Write results of the expression here */
+){
+  int rc = SQLITE_OK;
 
-  if( pReader->nData==0 ){
-    pReader->pData = NULL;
-    return;
-  }
+  /* Initialize the output buffer. If this is an empty query (pExpr==0), 
+  ** this is all that needs to be done. Empty queries produce empty 
+  ** result sets.
+  */
+  dataBufferInit(pRes, 0);
 
-  n = fts3GetVarint32(pReader->pData, &i);
-  if( i==POS_COLUMN ){
-    n += fts3GetVarint32(pReader->pData+n, &pReader->iColumn);
-    pReader->iPosition = 0;
-    pReader->iStartOffset = 0;
-    n += fts3GetVarint32(pReader->pData+n, &i);
-  }
-  /* Should never see adjacent column changes. */
-  assert( i!=POS_COLUMN );
+  if( pExpr ){
+    if( pExpr->eType==FTSQUERY_PHRASE ){
+      DocListType eType = DL_DOCIDS;
+      if( pExpr->pParent && pExpr->pParent->eType==FTSQUERY_NEAR ){
+        eType = DL_POSITIONS;
+      }
+      rc = docListOfPhrase(pTab, pExpr->pPhrase, eType, pRes);
+    }else{
+      DataBuffer lhs;
+      DataBuffer rhs;
 
-  if( i==POS_END ){
-    pReader->nData = 0;
-    pReader->pData = NULL;
-    return;
+      dataBufferInit(&rhs, 0);
+      if( SQLITE_OK==(rc = evalFts3Expr(pTab, pExpr->pLeft, &lhs)) 
+       && SQLITE_OK==(rc = evalFts3Expr(pTab, pExpr->pRight, &rhs)) 
+      ){
+        switch( pExpr->eType ){
+          case FTSQUERY_NEAR: {
+            int nToken;
+            Fts3Expr *pLeft;
+            DocListType eType = DL_DOCIDS;
+            if( pExpr->pParent && pExpr->pParent->eType==FTSQUERY_NEAR ){
+              eType = DL_POSITIONS;
+            }
+            pLeft = pExpr->pLeft;
+            while( pLeft->eType==FTSQUERY_NEAR ){ 
+              pLeft=pLeft->pRight;
+            }
+            assert( pExpr->pRight->eType==FTSQUERY_PHRASE );
+            assert( pLeft->eType==FTSQUERY_PHRASE );
+            nToken = pLeft->pPhrase->nToken + pExpr->pRight->pPhrase->nToken;
+            docListPhraseMerge(lhs.pData, lhs.nData, rhs.pData, rhs.nData, 
+                pExpr->nNear+1, nToken, eType, pRes
+            );
+            break;
+          }
+          case FTSQUERY_NOT: {
+            docListExceptMerge(lhs.pData, lhs.nData, rhs.pData, rhs.nData,pRes);
+            break;
+          }
+          case FTSQUERY_AND: {
+            docListAndMerge(lhs.pData, lhs.nData, rhs.pData, rhs.nData, pRes);
+            break;
+          }
+          case FTSQUERY_OR: {
+            docListOrMerge(lhs.pData, lhs.nData, rhs.pData, rhs.nData, pRes);
+            break;
+          }
+        }
+      }
+      dataBufferDestroy(&lhs);
+      dataBufferDestroy(&rhs);
+    }
   }
 
-  pReader->iPosition += i-POS_BASE;
-  if( pReader->iType==DL_POSITIONS_OFFSETS ){
-    n += fts3GetVarint32(pReader->pData+n, &i);
-    pReader->iStartOffset += i;
-    n += fts3GetVarint32(pReader->pData+n, &i);
-    pReader->iEndOffset = pReader->iStartOffset+i;
-  }
-  assert( n<=pReader->nData );
-  pReader->pData += n;
-  pReader->nData -= n;
+  return rc;
 }
 
-static void plrInit(PLReader *pReader, DLReader *pDLReader){
-  pReader->pData = dlrPosData(pDLReader);
-  pReader->nData = dlrPosDataLen(pDLReader);
-  pReader->iType = pDLReader->iType;
-  pReader->iColumn = 0;
-  pReader->iPosition = 0;
-  pReader->iStartOffset = 0;
-  pReader->iEndOffset = 0;
-  plrStep(pReader);
-}
-static void plrDestroy(PLReader *pReader){
-  SCRAMBLE(pReader);
+/* TODO(shess) Refactor the code to remove this forward decl. */
+static int flushPendingTerms(fulltext_vtab *v);
+
+/* Perform a full-text query using the search expression in
+** zInput[0..nInput-1].  Return a list of matching documents
+** in pResult.
+**
+** Queries must match column iColumn.  Or if iColumn>=nColumn
+** they are allowed to match against any column.
+*/
+static int fulltextQuery(
+  fulltext_vtab *v,      /* The full text index */
+  int iColumn,           /* Match against this column by default */
+  const char *zInput,    /* The query string */
+  int nInput,            /* Number of bytes in zInput[] */
+  DataBuffer *pResult,   /* Write the result doclist here */
+  Fts3Expr **ppExpr        /* Put parsed query string here */
+){
+  int rc;
+
+  /* TODO(shess) Instead of flushing pendingTerms, we could query for
+  ** the relevant term and merge the doclist into what we receive from
+  ** the database.  Wait and see if this is a common issue, first.
+  **
+  ** A good reason not to flush is to not generate update-related
+  ** error codes from here.
+  */
+
+  /* Flush any buffered updates before executing the query. */
+  rc = flushPendingTerms(v);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
+  /* Parse the query passed to the MATCH operator. */
+  rc = sqlite3Fts3ExprParse(v->pTokenizer, 
+      v->azColumn, v->nColumn, iColumn, zInput, nInput, ppExpr
+  );
+  if( rc!=SQLITE_OK ){
+    assert( 0==(*ppExpr) );
+    return rc;
+  }
+
+  return evalFts3Expr(v, *ppExpr, pResult);
 }
 
-/*******************************************************************/
-/* PLWriter is used in constructing a document's position list.  As a
-** convenience, if iType is DL_DOCIDS, PLWriter becomes a no-op.
-** PLWriter writes to the associated DLWriter's buffer.
-**
-** plwInit - init for writing a document's poslist.
-** plwDestroy - clear a writer.
-** plwAdd - append position and offset information.
-** plwCopy - copy next position's data from reader to writer.
-** plwTerminate - add any necessary doclist terminator.
+/*
+** This is the xFilter interface for the virtual table.  See
+** the virtual table xFilter method documentation for additional
+** information.
 **
-** Calling plwAdd() after plwTerminate() may result in a corrupt
-** doclist.
-*/
-/* TODO(shess) Until we've written the second item, we can cache the
-** first item's information.  Then we'd have three states:
+** If idxNum==QUERY_GENERIC then do a full table scan against
+** the %_content table.
 **
-** - initialized with docid, no positions.
-** - docid and one position.
-** - docid and multiple positions.
+** If idxNum==QUERY_DOCID then do a docid lookup for a single entry
+** in the %_content table.
 **
-** Only the last state needs to actually write to dlw->b, which would
-** be an improvement in the DLCollector case.
+** If idxNum>=QUERY_FULLTEXT then use the full text index.  The
+** column on the left-hand side of the MATCH operator is column
+** number idxNum-QUERY_FULLTEXT, 0 indexed.  argv[0] is the right-hand
+** side of the MATCH operator.
 */
-typedef struct PLWriter {
-  DLWriter *dlw;
-
-  int iColumn;    /* the last column written */
-  int iPos;       /* the last position written */
-  int iOffset;    /* the last start offset written */
-} PLWriter;
-
-/* TODO(shess) In the case where the parent is reading these values
-** from a PLReader, we could optimize to a copy if that PLReader has
-** the same type as pWriter.
+/* TODO(shess) Upgrade the cursor initialization and destruction to
+** account for fulltextFilter() being called multiple times on the
+** same cursor.  The current solution is very fragile.  Apply fix to
+** fts3 as appropriate.
 */
-static void plwAdd(PLWriter *pWriter, int iColumn, int iPos,
-                   int iStartOffset, int iEndOffset){
-  /* Worst-case space for POS_COLUMN, iColumn, iPosDelta,
-  ** iStartOffsetDelta, and iEndOffsetDelta.
-  */
-  char c[5*VARINT_MAX];
-  int n = 0;
-
-  /* Ban plwAdd() after plwTerminate(). */
-  assert( pWriter->iPos!=-1 );
+static int fulltextFilter(
+  sqlite3_vtab_cursor *pCursor,     /* The cursor used for this query */
+  int idxNum, const char *idxStr,   /* Which indexing scheme to use */
+  int argc, sqlite3_value **argv    /* Arguments for the indexing scheme */
+){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  fulltext_vtab *v = cursor_vtab(c);
+  int rc;
 
-  if( pWriter->dlw->iType==DL_DOCIDS ) return;
+  FTSTRACE(("FTS3 Filter %p\n",pCursor));
 
-  if( iColumn!=pWriter->iColumn ){
-    n += fts3PutVarint(c+n, POS_COLUMN);
-    n += fts3PutVarint(c+n, iColumn);
-    pWriter->iColumn = iColumn;
-    pWriter->iPos = 0;
-    pWriter->iOffset = 0;
-  }
-  assert( iPos>=pWriter->iPos );
-  n += fts3PutVarint(c+n, POS_BASE+(iPos-pWriter->iPos));
-  pWriter->iPos = iPos;
-  if( pWriter->dlw->iType==DL_POSITIONS_OFFSETS ){
-    assert( iStartOffset>=pWriter->iOffset );
-    n += fts3PutVarint(c+n, iStartOffset-pWriter->iOffset);
-    pWriter->iOffset = iStartOffset;
-    assert( iEndOffset>=iStartOffset );
-    n += fts3PutVarint(c+n, iEndOffset-iStartOffset);
+  /* If the cursor has a statement that was not prepared according to
+  ** idxNum, clear it.  I believe all calls to fulltextFilter with a
+  ** given cursor will have the same idxNum , but in this case it's
+  ** easy to be safe.
+  */
+  if( c->pStmt && c->iCursorType!=idxNum ){
+    sqlite3_finalize(c->pStmt);
+    c->pStmt = NULL;
+  }
+
+  /* Get a fresh statement appropriate to idxNum. */
+  /* TODO(shess): Add a prepared-statement cache in the vt structure.
+  ** The cache must handle multiple open cursors.  Easier to cache the
+  ** statement variants at the vt to reduce malloc/realloc/free here.
+  ** Or we could have a StringBuffer variant which allowed stack
+  ** construction for small values.
+  */
+  if( !c->pStmt ){
+    StringBuffer sb;
+    initStringBuffer(&sb);
+    append(&sb, "SELECT docid, ");
+    appendList(&sb, v->nColumn, v->azContentColumn);
+    append(&sb, " FROM %_content");
+    if( idxNum!=QUERY_GENERIC ) append(&sb, " WHERE docid = ?");
+    rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt,
+                     stringBufferData(&sb));
+    stringBufferDestroy(&sb);
+    if( rc!=SQLITE_OK ) return rc;
+    c->iCursorType = idxNum;
+  }else{
+    sqlite3_reset(c->pStmt);
+    assert( c->iCursorType==idxNum );
   }
-  dataBufferAppend(pWriter->dlw->b, c, n);
-}
-static void plwCopy(PLWriter *pWriter, PLReader *pReader){
-  plwAdd(pWriter, plrColumn(pReader), plrPosition(pReader),
-         plrStartOffset(pReader), plrEndOffset(pReader));
-}
-static void plwInit(PLWriter *pWriter, DLWriter *dlw, sqlite_int64 iDocid){
-  char c[VARINT_MAX];
-  int n;
 
-  pWriter->dlw = dlw;
+  switch( idxNum ){
+    case QUERY_GENERIC:
+      break;
 
-  /* Docids must ascend. */
-  assert( !pWriter->dlw->has_iPrevDocid || iDocid>pWriter->dlw->iPrevDocid );
-  n = fts3PutVarint(c, iDocid-pWriter->dlw->iPrevDocid);
-  dataBufferAppend(pWriter->dlw->b, c, n);
-  pWriter->dlw->iPrevDocid = iDocid;
-#ifndef NDEBUG
-  pWriter->dlw->has_iPrevDocid = 1;
-#endif
+    case QUERY_DOCID:
+      rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
+      if( rc!=SQLITE_OK ) return rc;
+      break;
 
-  pWriter->iColumn = 0;
-  pWriter->iPos = 0;
-  pWriter->iOffset = 0;
-}
-/* TODO(shess) Should plwDestroy() also terminate the doclist?  But
-** then plwDestroy() would no longer be just a destructor, it would
-** also be doing work, which isn't consistent with the overall idiom.
-** Another option would be for plwAdd() to always append any necessary
-** terminator, so that the output is always correct.  But that would
-** add incremental work to the common case with the only benefit being
-** API elegance.  Punt for now.
-*/
-static void plwTerminate(PLWriter *pWriter){
-  if( pWriter->dlw->iType>DL_DOCIDS ){
-    char c[VARINT_MAX];
-    int n = fts3PutVarint(c, POS_END);
-    dataBufferAppend(pWriter->dlw->b, c, n);
+    default:   /* full-text search */
+    {
+      int iCol = idxNum-QUERY_FULLTEXT;
+      const char *zQuery = (const char *)sqlite3_value_text(argv[0]);
+      assert( idxNum<=QUERY_FULLTEXT+v->nColumn);
+      assert( argc==1 );
+      if( c->result.nData!=0 ){
+        /* This case happens if the same cursor is used repeatedly. */
+        dlrDestroy(&c->reader);
+        dataBufferReset(&c->result);
+      }else{
+        dataBufferInit(&c->result, 0);
+      }
+      rc = fulltextQuery(v, iCol, zQuery, -1, &c->result, &c->pExpr);
+      if( rc!=SQLITE_OK ) return rc;
+      if( c->result.nData!=0 ){
+        dlrInit(&c->reader, DL_DOCIDS, c->result.pData, c->result.nData);
+      }
+      break;
+    }
   }
-#ifndef NDEBUG
-  /* Mark as terminated for assert in plwAdd(). */
-  pWriter->iPos = -1;
-#endif
-}
-static void plwDestroy(PLWriter *pWriter){
-  SCRAMBLE(pWriter);
+
+  return fulltextNext(pCursor);
 }
 
-/*******************************************************************/
-/* DLCollector wraps PLWriter and DLWriter to provide a
-** dynamically-allocated doclist area to use during tokenization.
-**
-** dlcNew - malloc up and initialize a collector.
-** dlcDelete - destroy a collector and all contained items.
-** dlcAddPos - append position and offset information.
-** dlcAddDoclist - add the collected doclist to the given buffer.
-** dlcNext - terminate the current document and open another.
+/* This is the xEof method of the virtual table.  The SQLite core
+** calls this routine to find out if it has reached the end of
+** a query's results set.
 */
-typedef struct DLCollector {
-  DataBuffer b;
-  DLWriter dlw;
-  PLWriter plw;
-} DLCollector;
+static int fulltextEof(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  return c->eof;
+}
 
-/* TODO(shess) This could also be done by calling plwTerminate() and
-** dataBufferAppend().  I tried that, expecting nominal performance
-** differences, but it seemed to pretty reliably be worth 1% to code
-** it this way.  I suspect it is the incremental malloc overhead (some
-** percentage of the plwTerminate() calls will cause a realloc), so
-** this might be worth revisiting if the DataBuffer implementation
-** changes.
+/* This is the xColumn method of the virtual table.  The SQLite
+** core calls this method during a query when it needs the value
+** of a column from the virtual table.  This method needs to use
+** one of the sqlite3_result_*() routines to store the requested
+** value back in the pContext.
 */
-static void dlcAddDoclist(DLCollector *pCollector, DataBuffer *b){
-  if( pCollector->dlw.iType>DL_DOCIDS ){
-    char c[VARINT_MAX];
-    int n = fts3PutVarint(c, POS_END);
-    dataBufferAppend2(b, pCollector->b.pData, pCollector->b.nData, c, n);
-  }else{
-    dataBufferAppend(b, pCollector->b.pData, pCollector->b.nData);
+static int fulltextColumn(sqlite3_vtab_cursor *pCursor,
+                          sqlite3_context *pContext, int idxCol){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  fulltext_vtab *v = cursor_vtab(c);
+
+  if( idxCol<v->nColumn ){
+    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1);
+    sqlite3_result_value(pContext, pVal);
+  }else if( idxCol==v->nColumn ){
+    /* The extra column whose name is the same as the table.
+    ** Return a blob which is a pointer to the cursor
+    */
+    sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT);
+  }else if( idxCol==v->nColumn+1 ){
+    /* The docid column, which is an alias for rowid. */
+    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, 0);
+    sqlite3_result_value(pContext, pVal);
   }
-}
-static void dlcNext(DLCollector *pCollector, sqlite_int64 iDocid){
-  plwTerminate(&pCollector->plw);
-  plwDestroy(&pCollector->plw);
-  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
-}
-static void dlcAddPos(DLCollector *pCollector, int iColumn, int iPos,
-                      int iStartOffset, int iEndOffset){
-  plwAdd(&pCollector->plw, iColumn, iPos, iStartOffset, iEndOffset);
+  return SQLITE_OK;
 }
 
-static DLCollector *dlcNew(sqlite_int64 iDocid, DocListType iType){
-  DLCollector *pCollector = sqlite3_malloc(sizeof(DLCollector));
-  dataBufferInit(&pCollector->b, 0);
-  dlwInit(&pCollector->dlw, iType, &pCollector->b);
-  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
-  return pCollector;
-}
-static void dlcDelete(DLCollector *pCollector){
-  plwDestroy(&pCollector->plw);
-  dlwDestroy(&pCollector->dlw);
-  dataBufferDestroy(&pCollector->b);
-  SCRAMBLE(pCollector);
-  sqlite3_free(pCollector);
-}
+/* This is the xRowid method.  The SQLite core calls this routine to
+** retrieve the rowid for the current row of the result set.  fts3
+** exposes %_content.docid as the rowid for the virtual table.  The
+** rowid should be written to *pRowid.
+*/
+static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
 
+  *pRowid = sqlite3_column_int64(c->pStmt, 0);
+  return SQLITE_OK;
+}
 
-/* Copy the doclist data of iType in pData/nData into *out, trimming
-** unnecessary data as we go.  Only columns matching iColumn are
-** copied, all columns copied if iColumn is -1.  Elements with no
-** matching columns are dropped.  The output is an iOutType doclist.
-*/
-/* NOTE(shess) This code is only valid after all doclists are merged.
-** If this is run before merges, then doclist items which represent
-** deletion will be trimmed, and will thus not effect a deletion
-** during the merge.
+/* Add all terms in [zText] to pendingTerms table.  If [iColumn] > 0,
+** we also store positions and offsets in the hash table using that
+** column number.
 */
-static void docListTrim(DocListType iType, const char *pData, int nData,
-                        int iColumn, DocListType iOutType, DataBuffer *out){
-  DLReader dlReader;
-  DLWriter dlWriter;
+static int buildTerms(fulltext_vtab *v, sqlite_int64 iDocid,
+                      const char *zText, int iColumn){
+  sqlite3_tokenizer *pTokenizer = v->pTokenizer;
+  sqlite3_tokenizer_cursor *pCursor;
+  const char *pToken;
+  int nTokenBytes;
+  int iStartOffset, iEndOffset, iPosition;
+  int rc;
 
-  assert( iOutType<=iType );
+  rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
+  if( rc!=SQLITE_OK ) return rc;
 
-  dlrInit(&dlReader, iType, pData, nData);
-  dlwInit(&dlWriter, iOutType, out);
+  pCursor->pTokenizer = pTokenizer;
+  while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
+                                                   &pToken, &nTokenBytes,
+                                                   &iStartOffset, &iEndOffset,
+                                                   &iPosition)) ){
+    DLCollector *p;
+    int nData;                   /* Size of doclist before our update. */
 
-  while( !dlrAtEnd(&dlReader) ){
-    PLReader plReader;
-    PLWriter plWriter;
-    int match = 0;
+    /* Positions can't be negative; we use -1 as a terminator
+     * internally.  Token can't be NULL or empty. */
+    if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){
+      rc = SQLITE_ERROR;
+      break;
+    }
 
-    plrInit(&plReader, &dlReader);
+    p = fts3HashFind(&v->pendingTerms, pToken, nTokenBytes);
+    if( p==NULL ){
+      nData = 0;
+      p = dlcNew(iDocid, DL_DEFAULT);
+      fts3HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);
 
-    while( !plrAtEnd(&plReader) ){
-      if( iColumn==-1 || plrColumn(&plReader)==iColumn ){
-        if( !match ){
-          plwInit(&plWriter, &dlWriter, dlrDocid(&dlReader));
-          match = 1;
-        }
-        plwAdd(&plWriter, plrColumn(&plReader), plrPosition(&plReader),
-               plrStartOffset(&plReader), plrEndOffset(&plReader));
-      }
-      plrStep(&plReader);
+      /* Overhead for our hash table entry, the key, and the value. */
+      v->nPendingData += sizeof(struct fts3HashElem)+sizeof(*p)+nTokenBytes;
+    }else{
+      nData = p->b.nData;
+      if( p->dlw.iPrevDocid!=iDocid ) dlcNext(p, iDocid);
     }
-    if( match ){
-      plwTerminate(&plWriter);
-      plwDestroy(&plWriter);
+    if( iColumn>=0 ){
+      dlcAddPos(p, iColumn, iPosition, iStartOffset, iEndOffset);
     }
 
-    plrDestroy(&plReader);
-    dlrStep(&dlReader);
+    /* Accumulate data added by dlcNew or dlcNext, and dlcAddPos. */
+    v->nPendingData += p->b.nData-nData;
   }
-  dlwDestroy(&dlWriter);
-  dlrDestroy(&dlReader);
-}
-
-/* Used by docListMerge() to keep doclists in the ascending order by
-** docid, then ascending order by age (so the newest comes first).
-*/
-typedef struct OrderedDLReader {
-  DLReader *pReader;
 
-  /* TODO(shess) If we assume that docListMerge pReaders is ordered by
-  ** age (which we do), then we could use pReader comparisons to break
-  ** ties.
+  /* TODO(shess) Check return?  Should this be able to cause errors at
+  ** this point?  Actually, same question about sqlite3_finalize(),
+  ** though one could argue that failure there means that the data is
+  ** not durable.  *ponder*
   */
-  int idx;
-} OrderedDLReader;
-
-/* Order eof to end, then by docid asc, idx desc. */
-static int orderedDLReaderCmp(OrderedDLReader *r1, OrderedDLReader *r2){
-  if( dlrAtEnd(r1->pReader) ){
-    if( dlrAtEnd(r2->pReader) ) return 0;  /* Both atEnd(). */
-    return 1;                              /* Only r1 atEnd(). */
-  }
-  if( dlrAtEnd(r2->pReader) ) return -1;   /* Only r2 atEnd(). */
-
-  if( dlrDocid(r1->pReader)<dlrDocid(r2->pReader) ) return -1;
-  if( dlrDocid(r1->pReader)>dlrDocid(r2->pReader) ) return 1;
-
-  /* Descending on idx. */
-  return r2->idx-r1->idx;
+  pTokenizer->pModule->xClose(pCursor);
+  if( SQLITE_DONE == rc ) return SQLITE_OK;
+  return rc;
 }
 
-/* Bubble p[0] to appropriate place in p[1..n-1].  Assumes that
-** p[1..n-1] is already sorted.
-*/
-/* TODO(shess) Is this frequent enough to warrant a binary search?
-** Before implementing that, instrument the code to check.  In most
-** current usage, I expect that p[0] will be less than p[1] a very
-** high proportion of the time.
-*/
-static void orderedDLReaderReorder(OrderedDLReader *p, int n){
-  while( n>1 && orderedDLReaderCmp(p, p+1)>0 ){
-    OrderedDLReader tmp = p[0];
-    p[0] = p[1];
-    p[1] = tmp;
-    n--;
-    p++;
+/* Add doclists for all terms in [pValues] to pendingTerms table. */
+static int insertTerms(fulltext_vtab *v, sqlite_int64 iDocid,
+                       sqlite3_value **pValues){
+  int i;
+  for(i = 0; i < v->nColumn ; ++i){
+    char *zText = (char*)sqlite3_value_text(pValues[i]);
+    int rc = buildTerms(v, iDocid, zText, i);
+    if( rc!=SQLITE_OK ) return rc;
   }
+  return SQLITE_OK;
 }
 
-/* Given an array of doclist readers, merge their doclist elements
-** into out in sorted order (by docid), dropping elements from older
-** readers when there is a duplicate docid.  pReaders is assumed to be
-** ordered by age, oldest first.
-*/
-/* TODO(shess) nReaders must be <= MERGE_COUNT.  This should probably
-** be fixed.
+/* Add empty doclists for all terms in the given row's content to
+** pendingTerms.
 */
-static void docListMerge(DataBuffer *out,
-                         DLReader *pReaders, int nReaders){
-  OrderedDLReader readers[MERGE_COUNT];
-  DLWriter writer;
-  int i, n;
-  const char *pStart = 0;
-  int nStart = 0;
-  sqlite_int64 iFirstDocid = 0, iLastDocid = 0;
+static int deleteTerms(fulltext_vtab *v, sqlite_int64 iDocid){
+  const char **pValues;
+  int i, rc;
 
-  assert( nReaders>0 );
-  if( nReaders==1 ){
-    dataBufferAppend(out, dlrDocData(pReaders), dlrAllDataBytes(pReaders));
-    return;
-  }
+  /* TODO(shess) Should we allow such tables at all? */
+  if( DL_DEFAULT==DL_DOCIDS ) return SQLITE_ERROR;
 
-  assert( nReaders<=MERGE_COUNT );
-  n = 0;
-  for(i=0; i<nReaders; i++){
-    assert( pReaders[i].iType==pReaders[0].iType );
-    readers[i].pReader = pReaders+i;
-    readers[i].idx = i;
-    n += dlrAllDataBytes(&pReaders[i]);
-  }
-  /* Conservatively size output to sum of inputs.  Output should end
-  ** up strictly smaller than input.
-  */
-  dataBufferExpand(out, n);
+  rc = content_select(v, iDocid, &pValues);
+  if( rc!=SQLITE_OK ) return rc;
 
-  /* Get the readers into sorted order. */
-  while( i-->0 ){
-    orderedDLReaderReorder(readers+i, nReaders-i);
+  for(i = 0 ; i < v->nColumn; ++i) {
+    rc = buildTerms(v, iDocid, pValues[i], -1);
+    if( rc!=SQLITE_OK ) break;
   }
 
-  dlwInit(&writer, pReaders[0].iType, out);
-  while( !dlrAtEnd(readers[0].pReader) ){
-    sqlite_int64 iDocid = dlrDocid(readers[0].pReader);
+  freeStringArray(v->nColumn, pValues);
+  return SQLITE_OK;
+}
 
-    /* If this is a continuation of the current buffer to copy, extend
-    ** that buffer.  memcpy() seems to be more efficient if it has a
-    ** lots of data to copy.
-    */
-    if( dlrDocData(readers[0].pReader)==pStart+nStart ){
-      nStart += dlrDocDataBytes(readers[0].pReader);
-    }else{
-      if( pStart!=0 ){
-        dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
-      }
-      pStart = dlrDocData(readers[0].pReader);
-      nStart = dlrDocDataBytes(readers[0].pReader);
-      iFirstDocid = iDocid;
-    }
-    iLastDocid = iDocid;
-    dlrStep(readers[0].pReader);
+/* TODO(shess) Refactor the code to remove this forward decl. */
+static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid);
 
-    /* Drop all of the older elements with the same docid. */
-    for(i=1; i<nReaders &&
-             !dlrAtEnd(readers[i].pReader) &&
-             dlrDocid(readers[i].pReader)==iDocid; i++){
-      dlrStep(readers[i].pReader);
-    }
+/* Insert a row into the %_content table; set *piDocid to be the ID of the
+** new row.  Add doclists for terms to pendingTerms.
+*/
+static int index_insert(fulltext_vtab *v, sqlite3_value *pRequestDocid,
+                        sqlite3_value **pValues, sqlite_int64 *piDocid){
+  int rc;
 
-    /* Get the readers back into order. */
-    while( i-->0 ){
-      orderedDLReaderReorder(readers+i, nReaders-i);
-    }
-  }
+  rc = content_insert(v, pRequestDocid, pValues);  /* execute an SQL INSERT */
+  if( rc!=SQLITE_OK ) return rc;
 
-  /* Copy over any remaining elements. */
-  if( nStart>0 ) dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
-  dlwDestroy(&writer);
+  /* docid column is an alias for rowid. */
+  *piDocid = sqlite3_last_insert_rowid(v->db);
+  rc = initPendingTerms(v, *piDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return insertTerms(v, *piDocid, pValues);
 }
 
-/* Helper function for posListUnion().  Compares the current position
-** between left and right, returning as standard C idiom of <0 if
-** left<right, >0 if left>right, and 0 if left==right.  "End" always
-** compares greater.
+/* Delete a row from the %_content table; add empty doclists for terms
+** to pendingTerms.
 */
-static int posListCmp(PLReader *pLeft, PLReader *pRight){
-  assert( pLeft->iType==pRight->iType );
-  if( pLeft->iType==DL_DOCIDS ) return 0;
+static int index_delete(fulltext_vtab *v, sqlite_int64 iRow){
+  int rc = initPendingTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
 
-  if( plrAtEnd(pLeft) ) return plrAtEnd(pRight) ? 0 : 1;
-  if( plrAtEnd(pRight) ) return -1;
+  rc = deleteTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
 
-  if( plrColumn(pLeft)<plrColumn(pRight) ) return -1;
-  if( plrColumn(pLeft)>plrColumn(pRight) ) return 1;
+  return content_delete(v, iRow);  /* execute an SQL DELETE */
+}
 
-  if( plrPosition(pLeft)<plrPosition(pRight) ) return -1;
-  if( plrPosition(pLeft)>plrPosition(pRight) ) return 1;
-  if( pLeft->iType==DL_POSITIONS ) return 0;
+/* Update a row in the %_content table; add delete doclists to
+** pendingTerms for old terms not in the new data, add insert doclists
+** to pendingTerms for terms in the new data.
+*/
+static int index_update(fulltext_vtab *v, sqlite_int64 iRow,
+                        sqlite3_value **pValues){
+  int rc = initPendingTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
 
-  if( plrStartOffset(pLeft)<plrStartOffset(pRight) ) return -1;
-  if( plrStartOffset(pLeft)>plrStartOffset(pRight) ) return 1;
+  /* Generate an empty doclist for each term that previously appeared in this
+   * row. */
+  rc = deleteTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
 
-  if( plrEndOffset(pLeft)<plrEndOffset(pRight) ) return -1;
-  if( plrEndOffset(pLeft)>plrEndOffset(pRight) ) return 1;
+  rc = content_update(v, pValues, iRow);  /* execute an SQL UPDATE */
+  if( rc!=SQLITE_OK ) return rc;
 
-  return 0;
+  /* Now add positions for terms which appear in the updated row. */
+  return insertTerms(v, iRow, pValues);
 }
 
-/* Write the union of position lists in pLeft and pRight to pOut.
-** "Union" in this case meaning "All unique position tuples".  Should
-** work with any doclist type, though both inputs and the output
-** should be the same type.
+/*******************************************************************/
+/* InteriorWriter is used to collect terms and block references into
+** interior nodes in %_segments.  See commentary at top of file for
+** format.
 */
-static void posListUnion(DLReader *pLeft, DLReader *pRight, DLWriter *pOut){
-  PLReader left, right;
-  PLWriter writer;
-
-  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
-  assert( pLeft->iType==pRight->iType );
-  assert( pLeft->iType==pOut->iType );
 
-  plrInit(&left, pLeft);
-  plrInit(&right, pRight);
-  plwInit(&writer, pOut, dlrDocid(pLeft));
+/* How large interior nodes can grow. */
+#define INTERIOR_MAX 2048
 
-  while( !plrAtEnd(&left) || !plrAtEnd(&right) ){
-    int c = posListCmp(&left, &right);
-    if( c<0 ){
-      plwCopy(&writer, &left);
-      plrStep(&left);
-    }else if( c>0 ){
-      plwCopy(&writer, &right);
-      plrStep(&right);
-    }else{
-      plwCopy(&writer, &left);
-      plrStep(&left);
-      plrStep(&right);
-    }
-  }
+/* Minimum number of terms per interior node (except the root). This
+** prevents large terms from making the tree too skinny - must be >0
+** so that the tree always makes progress.  Note that the min tree
+** fanout will be INTERIOR_MIN_TERMS+1.
+*/
+#define INTERIOR_MIN_TERMS 7
+#if INTERIOR_MIN_TERMS<1
+# error INTERIOR_MIN_TERMS must be greater than 0.
+#endif
 
-  plwTerminate(&writer);
-  plwDestroy(&writer);
-  plrDestroy(&left);
-  plrDestroy(&right);
-}
+/* ROOT_MAX controls how much data is stored inline in the segment
+** directory.
+*/
+/* TODO(shess) Push ROOT_MAX down to whoever is writing things.  It's
+** only here so that interiorWriterRootInfo() and leafWriterRootInfo()
+** can both see it, but if the caller passed it in, we wouldn't even
+** need a define.
+*/
+#define ROOT_MAX 1024
+#if ROOT_MAX<VARINT_MAX*2
+# error ROOT_MAX must have enough space for a header.
+#endif
 
-/* Write the union of doclists in pLeft and pRight to pOut.  For
-** docids in common between the inputs, the union of the position
-** lists is written.  Inputs and outputs are always type DL_DEFAULT.
+/* InteriorBlock stores a linked-list of interior blocks while a lower
+** layer is being constructed.
 */
-static void docListUnion(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
+typedef struct InteriorBlock {
+  DataBuffer term;           /* Leftmost term in block's subtree. */
+  DataBuffer data;           /* Accumulated data for the block. */
+  struct InteriorBlock *next;
+} InteriorBlock;
 
-  if( nLeft==0 ){
-    if( nRight!=0) dataBufferAppend(pOut, pRight, nRight);
-    return;
-  }
-  if( nRight==0 ){
-    dataBufferAppend(pOut, pLeft, nLeft);
-    return;
-  }
+static InteriorBlock *interiorBlockNew(int iHeight, sqlite_int64 iChildBlock,
+                                       const char *pTerm, int nTerm){
+  InteriorBlock *block = sqlite3_malloc(sizeof(InteriorBlock));
+  char c[VARINT_MAX+VARINT_MAX];
+  int n;
 
-  dlrInit(&left, DL_DEFAULT, pLeft, nLeft);
-  dlrInit(&right, DL_DEFAULT, pRight, nRight);
-  dlwInit(&writer, DL_DEFAULT, pOut);
+  if( block ){
+    memset(block, 0, sizeof(*block));
+    dataBufferInit(&block->term, 0);
+    dataBufferReplace(&block->term, pTerm, nTerm);
 
-  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
-    if( dlrAtEnd(&right) ){
-      dlwCopy(&writer, &left);
-      dlrStep(&left);
-    }else if( dlrAtEnd(&left) ){
-      dlwCopy(&writer, &right);
-      dlrStep(&right);
-    }else if( dlrDocid(&left)<dlrDocid(&right) ){
-      dlwCopy(&writer, &left);
-      dlrStep(&left);
-    }else if( dlrDocid(&left)>dlrDocid(&right) ){
-      dlwCopy(&writer, &right);
-      dlrStep(&right);
-    }else{
-      posListUnion(&left, &right, &writer);
-      dlrStep(&left);
-      dlrStep(&right);
-    }
+    n = fts3PutVarint(c, iHeight);
+    n += fts3PutVarint(c+n, iChildBlock);
+    dataBufferInit(&block->data, INTERIOR_MAX);
+    dataBufferReplace(&block->data, c, n);
   }
-
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+  return block;
 }
 
-/* 
-** This function is used as part of the implementation of phrase and
-** NEAR matching.
-**
-** pLeft and pRight are DLReaders positioned to the same docid in
-** lists of type DL_POSITION. This function writes an entry to the
-** DLWriter pOut for each position in pRight that is less than
-** (nNear+1) greater (but not equal to or smaller) than a position 
-** in pLeft. For example, if nNear is 0, and the positions contained
-** by pLeft and pRight are:
-**
-**    pLeft:  5 10 15 20
-**    pRight: 6  9 17 21
-**
-** then the docid is added to pOut. If pOut is of type DL_POSITIONS,
-** then a positionids "6" and "21" are also added to pOut.
-**
-** If boolean argument isSaveLeft is true, then positionids are copied
-** from pLeft instead of pRight. In the example above, the positions "5"
-** and "20" would be added instead of "6" and "21".
-*/
-static void posListPhraseMerge(
-  DLReader *pLeft, 
-  DLReader *pRight,
-  int nNear,
-  int isSaveLeft,
-  DLWriter *pOut
-){
-  PLReader left, right;
-  PLWriter writer;
-  int match = 0;
+#ifndef NDEBUG
+/* Verify that the data is readable as an interior node. */
+static void interiorBlockValidate(InteriorBlock *pBlock){
+  const char *pData = pBlock->data.pData;
+  int nData = pBlock->data.nData;
+  int n, iDummy;
+  sqlite_int64 iBlockid;
 
-  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
-  assert( pOut->iType!=DL_POSITIONS_OFFSETS );
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
 
-  plrInit(&left, pLeft);
-  plrInit(&right, pRight);
+  /* Must lead with height of node as a varint(n), n>0 */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( n>0 );
+  assert( iDummy>0 );
+  assert( n<nData );
+  pData += n;
+  nData -= n;
 
-  while( !plrAtEnd(&left) && !plrAtEnd(&right) ){
-    if( plrColumn(&left)<plrColumn(&right) ){
-      plrStep(&left);
-    }else if( plrColumn(&left)>plrColumn(&right) ){
-      plrStep(&right);
-    }else if( plrPosition(&left)>=plrPosition(&right) ){
-      plrStep(&right);
-    }else{
-      if( (plrPosition(&right)-plrPosition(&left))<=(nNear+1) ){
-        if( !match ){
-          plwInit(&writer, pOut, dlrDocid(pLeft));
-          match = 1;
-        }
-        if( !isSaveLeft ){
-          plwAdd(&writer, plrColumn(&right), plrPosition(&right), 0, 0);
-        }else{
-          plwAdd(&writer, plrColumn(&left), plrPosition(&left), 0, 0);
-        }
-        plrStep(&right);
-      }else{
-        plrStep(&left);
-      }
+  /* Must contain iBlockid. */
+  n = fts3GetVarint(pData, &iBlockid);
+  assert( n>0 );
+  assert( n<=nData );
+  pData += n;
+  nData -= n;
+
+  /* Zero or more terms of positive length */
+  if( nData!=0 ){
+    /* First term is not delta-encoded. */
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0);
+    assert( n+iDummy<=nData );
+    pData += n+iDummy;
+    nData -= n+iDummy;
+
+    /* Following terms delta-encoded. */
+    while( nData!=0 ){
+      /* Length of shared prefix. */
+      n = fts3GetVarint32(pData, &iDummy);
+      assert( n>0 );
+      assert( iDummy>=0 );
+      assert( n<nData );
+      pData += n;
+      nData -= n;
+
+      /* Length and data of distinct suffix. */
+      n = fts3GetVarint32(pData, &iDummy);
+      assert( n>0 );
+      assert( iDummy>0 );
+      assert( n+iDummy>0);
+      assert( n+iDummy<=nData );
+      pData += n+iDummy;
+      nData -= n+iDummy;
     }
   }
+}
+#define ASSERT_VALID_INTERIOR_BLOCK(x) interiorBlockValidate(x)
+#else
+#define ASSERT_VALID_INTERIOR_BLOCK(x) assert( 1 )
+#endif
 
-  if( match ){
-    plwTerminate(&writer);
-    plwDestroy(&writer);
-  }
+typedef struct InteriorWriter {
+  int iHeight;                   /* from 0 at leaves. */
+  InteriorBlock *first, *last;
+  struct InteriorWriter *parentWriter;
 
-  plrDestroy(&left);
-  plrDestroy(&right);
-}
+  DataBuffer term;               /* Last term written to block "last". */
+  sqlite_int64 iOpeningChildBlock; /* First child block in block "last". */
+#ifndef NDEBUG
+  sqlite_int64 iLastChildBlock;  /* for consistency checks. */
+#endif
+} InteriorWriter;
 
-/*
-** Compare the values pointed to by the PLReaders passed as arguments. 
-** Return -1 if the value pointed to by pLeft is considered less than
-** the value pointed to by pRight, +1 if it is considered greater
-** than it, or 0 if it is equal. i.e.
-**
-**     (*pLeft - *pRight)
-**
-** A PLReader that is in the EOF condition is considered greater than
-** any other. If neither argument is in EOF state, the return value of
-** plrColumn() is used. If the plrColumn() values are equal, the
-** comparison is on the basis of plrPosition().
+/* Initialize an interior node where pTerm[nTerm] marks the leftmost
+** term in the tree.  iChildBlock is the leftmost child block at the
+** next level down the tree.
 */
-static int plrCompare(PLReader *pLeft, PLReader *pRight){
-  assert(!plrAtEnd(pLeft) || !plrAtEnd(pRight));
+static void interiorWriterInit(int iHeight, const char *pTerm, int nTerm,
+                               sqlite_int64 iChildBlock,
+                               InteriorWriter *pWriter){
+  InteriorBlock *block;
+  assert( iHeight>0 );
+  CLEAR(pWriter);
 
-  if( plrAtEnd(pRight) || plrAtEnd(pLeft) ){
-    return (plrAtEnd(pRight) ? -1 : 1);
-  }
-  if( plrColumn(pLeft)!=plrColumn(pRight) ){
-    return ((plrColumn(pLeft)<plrColumn(pRight)) ? -1 : 1);
-  }
-  if( plrPosition(pLeft)!=plrPosition(pRight) ){
-    return ((plrPosition(pLeft)<plrPosition(pRight)) ? -1 : 1);
-  }
-  return 0;
+  pWriter->iHeight = iHeight;
+  pWriter->iOpeningChildBlock = iChildBlock;
+#ifndef NDEBUG
+  pWriter->iLastChildBlock = iChildBlock;
+#endif
+  block = interiorBlockNew(iHeight, iChildBlock, pTerm, nTerm);
+  pWriter->last = pWriter->first = block;
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+  dataBufferInit(&pWriter->term, 0);
 }
 
-/* We have two doclists with positions:  pLeft and pRight. Depending
-** on the value of the nNear parameter, perform either a phrase
-** intersection (if nNear==0) or a NEAR intersection (if nNear>0)
-** and write the results into pOut.
-**
-** A phrase intersection means that two documents only match
-** if pLeft.iPos+1==pRight.iPos.
-**
-** A NEAR intersection means that two documents only match if 
-** (abs(pLeft.iPos-pRight.iPos)<nNear).
-**
-** If a NEAR intersection is requested, then the nPhrase argument should
-** be passed the number of tokens in the two operands to the NEAR operator
-** combined. For example:
-**
-**       Query syntax               nPhrase
-**      ------------------------------------
-**       "A B C" NEAR "D E"         5
-**       A NEAR B                   2
-**
-** iType controls the type of data written to pOut.  If iType is
-** DL_POSITIONS, the positions are those from pRight.
+/* Append the child node rooted at iChildBlock to the interior node,
+** with pTerm[nTerm] as the leftmost term in iChildBlock's subtree.
 */
-static void docListPhraseMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  int nNear,            /* 0 for a phrase merge, non-zero for a NEAR merge */
-  int nPhrase,          /* Number of tokens in left+right operands to NEAR */
-  DocListType iType,    /* Type of doclist to write to pOut */
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
-
-  if( nLeft==0 || nRight==0 ) return;
-
-  assert( iType!=DL_POSITIONS_OFFSETS );
-
-  dlrInit(&left, DL_POSITIONS, pLeft, nLeft);
-  dlrInit(&right, DL_POSITIONS, pRight, nRight);
-  dlwInit(&writer, iType, pOut);
+static void interiorWriterAppend(InteriorWriter *pWriter,
+                                 const char *pTerm, int nTerm,
+                                 sqlite_int64 iChildBlock){
+  char c[VARINT_MAX+VARINT_MAX];
+  int n, nPrefix = 0;
 
-  while( !dlrAtEnd(&left) && !dlrAtEnd(&right) ){
-    if( dlrDocid(&left)<dlrDocid(&right) ){
-      dlrStep(&left);
-    }else if( dlrDocid(&right)<dlrDocid(&left) ){
-      dlrStep(&right);
-    }else{
-      if( nNear==0 ){
-        posListPhraseMerge(&left, &right, 0, 0, &writer);
-      }else{
-        /* This case occurs when two terms (simple terms or phrases) are
-         * connected by a NEAR operator, span (nNear+1). i.e.
-         *
-         *     '"terrible company" NEAR widget'
-         */
-        DataBuffer one = {0, 0, 0};
-        DataBuffer two = {0, 0, 0};
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
 
-        DLWriter dlwriter2;
-        DLReader dr1 = {0, 0, 0, 0, 0}; 
-        DLReader dr2 = {0, 0, 0, 0, 0};
+  /* The first term written into an interior node is actually
+  ** associated with the second child added (the first child was added
+  ** in interiorWriterInit, or in the if clause at the bottom of this
+  ** function).  That term gets encoded straight up, with nPrefix left
+  ** at 0.
+  */
+  if( pWriter->term.nData==0 ){
+    n = fts3PutVarint(c, nTerm);
+  }else{
+    while( nPrefix<pWriter->term.nData &&
+           pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
+      nPrefix++;
+    }
 
-        dlwInit(&dlwriter2, iType, &one);
-        posListPhraseMerge(&right, &left, nNear-3+nPhrase, 1, &dlwriter2);
-        dlwInit(&dlwriter2, iType, &two);
-        posListPhraseMerge(&left, &right, nNear-1, 0, &dlwriter2);
+    n = fts3PutVarint(c, nPrefix);
+    n += fts3PutVarint(c+n, nTerm-nPrefix);
+  }
 
-        if( one.nData) dlrInit(&dr1, iType, one.pData, one.nData);
-        if( two.nData) dlrInit(&dr2, iType, two.pData, two.nData);
+#ifndef NDEBUG
+  pWriter->iLastChildBlock++;
+#endif
+  assert( pWriter->iLastChildBlock==iChildBlock );
 
-        if( !dlrAtEnd(&dr1) || !dlrAtEnd(&dr2) ){
-          PLReader pr1 = {0};
-          PLReader pr2 = {0};
+  /* Overflow to a new block if the new term makes the current block
+  ** too big, and the current block already has enough terms.
+  */
+  if( pWriter->last->data.nData+n+nTerm-nPrefix>INTERIOR_MAX &&
+      iChildBlock-pWriter->iOpeningChildBlock>INTERIOR_MIN_TERMS ){
+    pWriter->last->next = interiorBlockNew(pWriter->iHeight, iChildBlock,
+                                           pTerm, nTerm);
+    pWriter->last = pWriter->last->next;
+    pWriter->iOpeningChildBlock = iChildBlock;
+    dataBufferReset(&pWriter->term);
+  }else{
+    dataBufferAppend2(&pWriter->last->data, c, n,
+                      pTerm+nPrefix, nTerm-nPrefix);
+    dataBufferReplace(&pWriter->term, pTerm, nTerm);
+  }
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+}
 
-          PLWriter plwriter;
-          plwInit(&plwriter, &writer, dlrDocid(dlrAtEnd(&dr1)?&dr2:&dr1));
+/* Free the space used by pWriter, including the linked-list of
+** InteriorBlocks, and parentWriter, if present.
+*/
+static int interiorWriterDestroy(InteriorWriter *pWriter){
+  InteriorBlock *block = pWriter->first;
 
-          if( one.nData ) plrInit(&pr1, &dr1);
-          if( two.nData ) plrInit(&pr2, &dr2);
-          while( !plrAtEnd(&pr1) || !plrAtEnd(&pr2) ){
-            int iCompare = plrCompare(&pr1, &pr2);
-            switch( iCompare ){
-              case -1:
-                plwCopy(&plwriter, &pr1);
-                plrStep(&pr1);
-                break;
-              case 1:
-                plwCopy(&plwriter, &pr2);
-                plrStep(&pr2);
-                break;
-              case 0:
-                plwCopy(&plwriter, &pr1);
-                plrStep(&pr1);
-                plrStep(&pr2);
-                break;
-            }
-          }
-          plwTerminate(&plwriter);
-        }
-        dataBufferDestroy(&one);
-        dataBufferDestroy(&two);
-      }
-      dlrStep(&left);
-      dlrStep(&right);
-    }
+  while( block!=NULL ){
+    InteriorBlock *b = block;
+    block = block->next;
+    dataBufferDestroy(&b->term);
+    dataBufferDestroy(&b->data);
+    sqlite3_free(b);
   }
-
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+  if( pWriter->parentWriter!=NULL ){
+    interiorWriterDestroy(pWriter->parentWriter);
+    sqlite3_free(pWriter->parentWriter);
+  }
+  dataBufferDestroy(&pWriter->term);
+  SCRAMBLE(pWriter);
+  return SQLITE_OK;
 }
 
-/* We have two DL_DOCIDS doclists:  pLeft and pRight.
-** Write the intersection of these two doclists into pOut as a
-** DL_DOCIDS doclist.
+/* If pWriter can fit entirely in ROOT_MAX, return it as the root info
+** directly, leaving *piEndBlockid unchanged.  Otherwise, flush
+** pWriter to %_segments, building a new layer of interior nodes, and
+** recursively ask for their root into.
 */
-static void docListAndMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
+static int interiorWriterRootInfo(fulltext_vtab *v, InteriorWriter *pWriter,
+                                  char **ppRootInfo, int *pnRootInfo,
+                                  sqlite_int64 *piEndBlockid){
+  InteriorBlock *block = pWriter->first;
+  sqlite_int64 iBlockid = 0;
+  int rc;
+
+  /* If we can fit the segment inline */
+  if( block==pWriter->last && block->data.nData<ROOT_MAX ){
+    *ppRootInfo = block->data.pData;
+    *pnRootInfo = block->data.nData;
+    return SQLITE_OK;
+  }
+
+  /* Flush the first block to %_segments, and create a new level of
+  ** interior node.
+  */
+  ASSERT_VALID_INTERIOR_BLOCK(block);
+  rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+  *piEndBlockid = iBlockid;
 
-  if( nLeft==0 || nRight==0 ) return;
+  pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
+  interiorWriterInit(pWriter->iHeight+1,
+                     block->term.pData, block->term.nData,
+                     iBlockid, pWriter->parentWriter);
 
-  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
-  dlrInit(&right, DL_DOCIDS, pRight, nRight);
-  dlwInit(&writer, DL_DOCIDS, pOut);
+  /* Flush additional blocks and append to the higher interior
+  ** node.
+  */
+  for(block=block->next; block!=NULL; block=block->next){
+    ASSERT_VALID_INTERIOR_BLOCK(block);
+    rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+    *piEndBlockid = iBlockid;
 
-  while( !dlrAtEnd(&left) && !dlrAtEnd(&right) ){
-    if( dlrDocid(&left)<dlrDocid(&right) ){
-      dlrStep(&left);
-    }else if( dlrDocid(&right)<dlrDocid(&left) ){
-      dlrStep(&right);
-    }else{
-      dlwAdd(&writer, dlrDocid(&left));
-      dlrStep(&left);
-      dlrStep(&right);
-    }
+    interiorWriterAppend(pWriter->parentWriter,
+                         block->term.pData, block->term.nData, iBlockid);
   }
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+  /* Parent node gets the chance to be the root. */
+  return interiorWriterRootInfo(v, pWriter->parentWriter,
+                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/* We have two DL_DOCIDS doclists:  pLeft and pRight.
-** Write the union of these two doclists into pOut as a
-** DL_DOCIDS doclist.
+/****************************************************************/
+/* InteriorReader is used to read off the data from an interior node
+** (see comment at top of file for the format).
 */
-static void docListOrMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
-
-  if( nLeft==0 ){
-    if( nRight!=0 ) dataBufferAppend(pOut, pRight, nRight);
-    return;
-  }
-  if( nRight==0 ){
-    dataBufferAppend(pOut, pLeft, nLeft);
-    return;
-  }
+typedef struct InteriorReader {
+  const char *pData;
+  int nData;
 
-  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
-  dlrInit(&right, DL_DOCIDS, pRight, nRight);
-  dlwInit(&writer, DL_DOCIDS, pOut);
+  DataBuffer term;          /* previous term, for decoding term delta. */
 
-  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
-    if( dlrAtEnd(&right) ){
-      dlwAdd(&writer, dlrDocid(&left));
-      dlrStep(&left);
-    }else if( dlrAtEnd(&left) ){
-      dlwAdd(&writer, dlrDocid(&right));
-      dlrStep(&right);
-    }else if( dlrDocid(&left)<dlrDocid(&right) ){
-      dlwAdd(&writer, dlrDocid(&left));
-      dlrStep(&left);
-    }else if( dlrDocid(&right)<dlrDocid(&left) ){
-      dlwAdd(&writer, dlrDocid(&right));
-      dlrStep(&right);
-    }else{
-      dlwAdd(&writer, dlrDocid(&left));
-      dlrStep(&left);
-      dlrStep(&right);
-    }
-  }
+  sqlite_int64 iBlockid;
+} InteriorReader;
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+static void interiorReaderDestroy(InteriorReader *pReader){
+  dataBufferDestroy(&pReader->term);
+  SCRAMBLE(pReader);
 }
 
-/* We have two DL_DOCIDS doclists:  pLeft and pRight.
-** Write into pOut as DL_DOCIDS doclist containing all documents that
-** occur in pLeft but not in pRight.
+/* TODO(shess) The assertions are great, but what if we're in NDEBUG
+** and the blob is empty or otherwise contains suspect data?
 */
-static void docListExceptMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
+static void interiorReaderInit(const char *pData, int nData,
+                               InteriorReader *pReader){
+  int n, nTerm;
 
-  if( nLeft==0 ) return;
-  if( nRight==0 ){
-    dataBufferAppend(pOut, pLeft, nLeft);
-    return;
-  }
+  /* Require at least the leading flag byte */
+  assert( nData>0 );
+  assert( pData[0]!='\0' );
 
-  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
-  dlrInit(&right, DL_DOCIDS, pRight, nRight);
-  dlwInit(&writer, DL_DOCIDS, pOut);
+  CLEAR(pReader);
 
-  while( !dlrAtEnd(&left) ){
-    while( !dlrAtEnd(&right) && dlrDocid(&right)<dlrDocid(&left) ){
-      dlrStep(&right);
-    }
-    if( dlrAtEnd(&right) || dlrDocid(&left)<dlrDocid(&right) ){
-      dlwAdd(&writer, dlrDocid(&left));
-    }
-    dlrStep(&left);
+  /* Decode the base blockid, and set the cursor to the first term. */
+  n = fts3GetVarint(pData+1, &pReader->iBlockid);
+  assert( 1+n<=nData );
+  pReader->pData = pData+1+n;
+  pReader->nData = nData-(1+n);
+
+  /* A single-child interior node (such as when a leaf node was too
+  ** large for the segment directory) won't have any terms.
+  ** Otherwise, decode the first term.
+  */
+  if( pReader->nData==0 ){
+    dataBufferInit(&pReader->term, 0);
+  }else{
+    n = fts3GetVarint32(pReader->pData, &nTerm);
+    dataBufferInit(&pReader->term, nTerm);
+    dataBufferReplace(&pReader->term, pReader->pData+n, nTerm);
+    assert( n+nTerm<=pReader->nData );
+    pReader->pData += n+nTerm;
+    pReader->nData -= n+nTerm;
   }
+}
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+static int interiorReaderAtEnd(InteriorReader *pReader){
+  return pReader->term.nData==0;
 }
 
-static char *string_dup_n(const char *s, int n){
-  char *str = sqlite3_malloc(n + 1);
-  memcpy(str, s, n);
-  str[n] = '\0';
-  return str;
+static sqlite_int64 interiorReaderCurrentBlockid(InteriorReader *pReader){
+  return pReader->iBlockid;
 }
 
-/* Duplicate a string; the caller must free() the returned string.
- * (We don't use strdup() since it is not part of the standard C library and
- * may not be available everywhere.) */
-static char *string_dup(const char *s){
-  return string_dup_n(s, strlen(s));
+static int interiorReaderTermBytes(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
+  return pReader->term.nData;
+}
+static const char *interiorReaderTerm(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
+  return pReader->term.pData;
 }
 
-/* Format a string, replacing each occurrence of the % character with
- * zDb.zName.  This may be more convenient than sqlite_mprintf()
- * when one string is used repeatedly in a format string.
- * The caller must free() the returned string. */
-static char *string_format(const char *zFormat,
-                           const char *zDb, const char *zName){
-  const char *p;
-  size_t len = 0;
-  size_t nDb = strlen(zDb);
-  size_t nName = strlen(zName);
-  size_t nFullTableName = nDb+1+nName;
-  char *result;
-  char *r;
+/* Step forward to the next term in the node. */
+static void interiorReaderStep(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
 
-  /* first compute length needed */
-  for(p = zFormat ; *p ; ++p){
-    len += (*p=='%' ? nFullTableName : 1);
-  }
-  len += 1;  /* for null terminator */
+  /* If the last term has been read, signal eof, else construct the
+  ** next term.
+  */
+  if( pReader->nData==0 ){
+    dataBufferReset(&pReader->term);
+  }else{
+    int n, nPrefix, nSuffix;
 
-  r = result = sqlite3_malloc(len);
-  for(p = zFormat; *p; ++p){
-    if( *p=='%' ){
-      memcpy(r, zDb, nDb);
-      r += nDb;
-      *r++ = '.';
-      memcpy(r, zName, nName);
-      r += nName;
-    } else {
-      *r++ = *p;
-    }
-  }
-  *r++ = '\0';
-  assert( r == result + len );
-  return result;
-}
+    n = fts3GetVarint32(pReader->pData, &nPrefix);
+    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
 
-static int sql_exec(sqlite3 *db, const char *zDb, const char *zName,
-                    const char *zFormat){
-  char *zCommand = string_format(zFormat, zDb, zName);
-  int rc;
-  FTSTRACE(("FTS3 sql: %s\n", zCommand));
-  rc = sqlite3_exec(db, zCommand, NULL, 0, NULL);
-  sqlite3_free(zCommand);
-  return rc;
-}
+    /* Truncate the current term and append suffix data. */
+    pReader->term.nData = nPrefix;
+    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
 
-static int sql_prepare(sqlite3 *db, const char *zDb, const char *zName,
-                       sqlite3_stmt **ppStmt, const char *zFormat){
-  char *zCommand = string_format(zFormat, zDb, zName);
-  int rc;
-  FTSTRACE(("FTS3 prepare: %s\n", zCommand));
-  rc = sqlite3_prepare_v2(db, zCommand, -1, ppStmt, NULL);
-  sqlite3_free(zCommand);
-  return rc;
+    assert( n+nSuffix<=pReader->nData );
+    pReader->pData += n+nSuffix;
+    pReader->nData -= n+nSuffix;
+  }
+  pReader->iBlockid++;
 }
 
-/* end utility functions */
+/* Compare the current term to pTerm[nTerm], returning strcmp-style
+** results.  If isPrefix, equality means equal through nTerm bytes.
+*/
+static int interiorReaderTermCmp(InteriorReader *pReader,
+                                 const char *pTerm, int nTerm, int isPrefix){
+  const char *pReaderTerm = interiorReaderTerm(pReader);
+  int nReaderTerm = interiorReaderTermBytes(pReader);
+  int c, n = nReaderTerm<nTerm ? nReaderTerm : nTerm;
 
-/* Forward reference */
-typedef struct fulltext_vtab fulltext_vtab;
+  if( n==0 ){
+    if( nReaderTerm>0 ) return -1;
+    if( nTerm>0 ) return 1;
+    return 0;
+  }
 
-/* A single term in a query is represented by an instances of
-** the following structure. Each word which may match against
-** document content is a term. Operators, like NEAR or OR, are
-** not terms. Query terms are organized as a flat list stored
-** in the Query.pTerms array.
-**
-** If the QueryTerm.nPhrase variable is non-zero, then the QueryTerm
-** is the first in a contiguous string of terms that are either part
-** of the same phrase, or connected by the NEAR operator.
-**
-** If the QueryTerm.nNear variable is non-zero, then the token is followed 
-** by a NEAR operator with span set to (nNear-1). For example, the 
-** following query:
-**
-** The QueryTerm.iPhrase variable stores the index of the token within
-** its phrase, indexed starting at 1, or 1 if the token is not part 
-** of any phrase.
-**
-** For example, the data structure used to represent the following query:
-**
-**     ... MATCH 'sqlite NEAR/5 google NEAR/2 "search engine"'
+  c = memcmp(pReaderTerm, pTerm, n);
+  if( c!=0 ) return c;
+  if( isPrefix && n==nTerm ) return 0;
+  return nReaderTerm - nTerm;
+}
+
+/****************************************************************/
+/* LeafWriter is used to collect terms and associated doclist data
+** into leaf blocks in %_segments (see top of file for format info).
+** Expected usage is:
 **
-** is:
+** LeafWriter writer;
+** leafWriterInit(0, 0, &writer);
+** while( sorted_terms_left_to_process ){
+**   // data is doclist data for that term.
+**   rc = leafWriterStep(v, &writer, pTerm, nTerm, pData, nData);
+**   if( rc!=SQLITE_OK ) goto err;
+** }
+** rc = leafWriterFinalize(v, &writer);
+**err:
+** leafWriterDestroy(&writer);
+** return rc;
 **
-**     {nPhrase=4, iPhrase=1, nNear=6, pTerm="sqlite"},
-**     {nPhrase=0, iPhrase=1, nNear=3, pTerm="google"},
-**     {nPhrase=0, iPhrase=1, nNear=0, pTerm="search"},
-**     {nPhrase=0, iPhrase=2, nNear=0, pTerm="engine"},
+** leafWriterStep() may write a collected leaf out to %_segments.
+** leafWriterFinalize() finishes writing any buffered data and stores
+** a root node in %_segdir.  leafWriterDestroy() frees all buffers and
+** InteriorWriters allocated as part of writing this segment.
 **
-** compiling the FTS3 syntax to Query structures is done by the parseQuery()
-** function.
+** TODO(shess) Document leafWriterStepMerge().
 */
-typedef struct QueryTerm {
-  short int nPhrase; /* How many following terms are part of the same phrase */
-  short int iPhrase; /* This is the i-th term of a phrase. */
-  short int iColumn; /* Column of the index that must match this term */
-  signed char nNear; /* term followed by a NEAR operator with span=(nNear-1) */
-  signed char isOr;  /* this term is preceded by "OR" */
-  signed char isNot; /* this term is preceded by "-" */
-  signed char isPrefix; /* this term is followed by "*" */
-  char *pTerm;       /* text of the term.  '\000' terminated.  malloced */
-  int nTerm;         /* Number of bytes in pTerm[] */
-} QueryTerm;
-
 
-/* A query string is parsed into a Query structure.
- *
- * We could, in theory, allow query strings to be complicated
- * nested expressions with precedence determined by parentheses.
- * But none of the major search engines do this.  (Perhaps the
- * feeling is that an parenthesized expression is two complex of
- * an idea for the average user to grasp.)  Taking our lead from
- * the major search engines, we will allow queries to be a list
- * of terms (with an implied AND operator) or phrases in double-quotes,
- * with a single optional "-" before each non-phrase term to designate
- * negation and an optional OR connector.
- *
- * OR binds more tightly than the implied AND, which is what the
- * major search engines seem to do.  So, for example:
- * 
- *    [one two OR three]     ==>    one AND (two OR three)
- *    [one OR two three]     ==>    (one OR two) AND three
- *
- * A "-" before a term matches all entries that lack that term.
- * The "-" must occur immediately before the term with in intervening
- * space.  This is how the search engines do it.
- *
- * A NOT term cannot be the right-hand operand of an OR.  If this
- * occurs in the query string, the NOT is ignored:
- *
- *    [one OR -two]          ==>    one OR two
- *
- */
-typedef struct Query {
-  fulltext_vtab *pFts;  /* The full text index */
-  int nTerms;           /* Number of terms in the query */
-  QueryTerm *pTerms;    /* Array of terms.  Space obtained from malloc() */
-  int nextIsOr;         /* Set the isOr flag on the next inserted term */
-  int nextIsNear;       /* Set the isOr flag on the next inserted term */
-  int nextColumn;       /* Next word parsed must be in this column */
-  int dfltColumn;       /* The default column */
-} Query;
+/* Put terms with data this big in their own block. */
+#define STANDALONE_MIN 1024
 
+/* Keep leaf blocks below this size. */
+#define LEAF_MAX 2048
 
-/*
-** An instance of the following structure keeps track of generated
-** matching-word offset information and snippets.
-*/
-typedef struct Snippet {
-  int nMatch;     /* Total number of matches */
-  int nAlloc;     /* Space allocated for aMatch[] */
-  struct snippetMatch { /* One entry for each matching term */
-    char snStatus;       /* Status flag for use while constructing snippets */
-    short int iCol;      /* The column that contains the match */
-    short int iTerm;     /* The index in Query.pTerms[] of the matching term */
-    int iToken;          /* The index of the matching document token */
-    short int nByte;     /* Number of bytes in the term */
-    int iStart;          /* The offset to the first character of the term */
-  } *aMatch;      /* Points to space obtained from malloc */
-  char *zOffset;  /* Text rendering of aMatch[] */
-  int nOffset;    /* strlen(zOffset) */
-  char *zSnippet; /* Snippet text */
-  int nSnippet;   /* strlen(zSnippet) */
-} Snippet;
+typedef struct LeafWriter {
+  int iLevel;
+  int idx;
+  sqlite_int64 iStartBlockid;     /* needed to create the root info */
+  sqlite_int64 iEndBlockid;       /* when we're done writing. */
 
+  DataBuffer term;                /* previous encoded term */
+  DataBuffer data;                /* encoding buffer */
 
-typedef enum QueryType {
-  QUERY_GENERIC,   /* table scan */
-  QUERY_DOCID,     /* lookup by docid */
-  QUERY_FULLTEXT   /* QUERY_FULLTEXT + [i] is a full-text search for column i*/
-} QueryType;
+  /* bytes of first term in the current node which distinguishes that
+  ** term from the last term of the previous node.
+  */
+  int nTermDistinct;
 
-typedef enum fulltext_statement {
-  CONTENT_INSERT_STMT,
-  CONTENT_SELECT_STMT,
-  CONTENT_UPDATE_STMT,
-  CONTENT_DELETE_STMT,
+  InteriorWriter parentWriter;    /* if we overflow */
+  int has_parent;
+} LeafWriter;
 
-  BLOCK_INSERT_STMT,
-  BLOCK_SELECT_STMT,
-  BLOCK_DELETE_STMT,
+static void leafWriterInit(int iLevel, int idx, LeafWriter *pWriter){
+  CLEAR(pWriter);
+  pWriter->iLevel = iLevel;
+  pWriter->idx = idx;
 
-  SEGDIR_MAX_INDEX_STMT,
-  SEGDIR_SET_STMT,
-  SEGDIR_SELECT_STMT,
-  SEGDIR_SPAN_STMT,
-  SEGDIR_DELETE_STMT,
-  SEGDIR_SELECT_ALL_STMT,
+  dataBufferInit(&pWriter->term, 32);
 
-  MAX_STMT                     /* Always at end! */
-} fulltext_statement;
+  /* Start out with a reasonably sized block, though it can grow. */
+  dataBufferInit(&pWriter->data, LEAF_MAX);
+}
 
-/* These must exactly match the enum above. */
-/* TODO(shess): Is there some risk that a statement will be used in two
-** cursors at once, e.g.  if a query joins a virtual table to itself?
-** If so perhaps we should move some of these to the cursor object.
-*/
-static const char *const fulltext_zStatement[MAX_STMT] = {
-  /* CONTENT_INSERT */ NULL,  /* generated in contentInsertStatement() */
-  /* CONTENT_SELECT */ NULL,  /* generated in contentSelectStatement() */
-  /* CONTENT_UPDATE */ NULL,  /* generated in contentUpdateStatement() */
-  /* CONTENT_DELETE */ "delete from %_content where docid = ?",
+#ifndef NDEBUG
+/* Verify that the data is readable as a leaf node. */
+static void leafNodeValidate(const char *pData, int nData){
+  int n, iDummy;
 
-  /* BLOCK_INSERT */
-  "insert into %_segments (blockid, block) values (null, ?)",
-  /* BLOCK_SELECT */ "select block from %_segments where blockid = ?",
-  /* BLOCK_DELETE */ "delete from %_segments where blockid between ? and ?",
+  if( nData==0 ) return;
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
 
-  /* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
-  /* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
-  /* SEGDIR_SELECT */
-  "select start_block, leaves_end_block, root from %_segdir "
-  " where level = ? order by idx",
-  /* SEGDIR_SPAN */
-  "select min(start_block), max(end_block) from %_segdir "
-  " where level = ? and start_block <> 0",
-  /* SEGDIR_DELETE */ "delete from %_segdir where level = ?",
-  /* SEGDIR_SELECT_ALL */
-  "select root, leaves_end_block from %_segdir order by level desc, idx",
-};
+  /* Must lead with a varint(0) */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( iDummy==0 );
+  assert( n>0 );
+  assert( n<nData );
+  pData += n;
+  nData -= n;
 
-/*
-** A connection to a fulltext index is an instance of the following
-** structure.  The xCreate and xConnect methods create an instance
-** of this structure and xDestroy and xDisconnect free that instance.
-** All other methods receive a pointer to the structure as one of their
-** arguments.
-*/
-struct fulltext_vtab {
-  sqlite3_vtab base;               /* Base class used by SQLite core */
-  sqlite3 *db;                     /* The database connection */
-  const char *zDb;                 /* logical database name */
-  const char *zName;               /* virtual table name */
-  int nColumn;                     /* number of columns in virtual table */
-  char **azColumn;                 /* column names.  malloced */
-  char **azContentColumn;          /* column names in content table; malloced */
-  sqlite3_tokenizer *pTokenizer;   /* tokenizer for inserts and queries */
+  /* Leading term length and data must fit in buffer. */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( n>0 );
+  assert( iDummy>0 );
+  assert( n+iDummy>0 );
+  assert( n+iDummy<nData );
+  pData += n+iDummy;
+  nData -= n+iDummy;
 
-  /* Precompiled statements which we keep as long as the table is
-  ** open.
-  */
-  sqlite3_stmt *pFulltextStatements[MAX_STMT];
+  /* Leading term's doclist length and data must fit. */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( n>0 );
+  assert( iDummy>0 );
+  assert( n+iDummy>0 );
+  assert( n+iDummy<=nData );
+  ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
+  pData += n+iDummy;
+  nData -= n+iDummy;
 
-  /* Precompiled statements used for segment merges.  We run a
-  ** separate select across the leaf level of each tree being merged.
-  */
-  sqlite3_stmt *pLeafSelectStmts[MERGE_COUNT];
-  /* The statement used to prepare pLeafSelectStmts. */
-#define LEAF_SELECT \
-  "select block from %_segments where blockid between ? and ? order by blockid"
+  /* Verify that trailing terms and doclists also are readable. */
+  while( nData!=0 ){
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>=0 );
+    assert( n<nData );
+    pData += n;
+    nData -= n;
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0 );
+    assert( n+iDummy<nData );
+    pData += n+iDummy;
+    nData -= n+iDummy;
 
-  /* These buffer pending index updates during transactions.
-  ** nPendingData estimates the memory size of the pending data.  It
-  ** doesn't include the hash-bucket overhead, nor any malloc
-  ** overhead.  When nPendingData exceeds kPendingThreshold, the
-  ** buffer is flushed even before the transaction closes.
-  ** pendingTerms stores the data, and is only valid when nPendingData
-  ** is >=0 (nPendingData<0 means pendingTerms has not been
-  ** initialized).  iPrevDocid is the last docid written, used to make
-  ** certain we're inserting in sorted order.
-  */
-  int nPendingData;
-#define kPendingThreshold (1*1024*1024)
-  sqlite_int64 iPrevDocid;
-  fts3Hash pendingTerms;
-};
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0 );
+    assert( n+iDummy<=nData );
+    ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
+    pData += n+iDummy;
+    nData -= n+iDummy;
+  }
+}
+#define ASSERT_VALID_LEAF_NODE(p, n) leafNodeValidate(p, n)
+#else
+#define ASSERT_VALID_LEAF_NODE(p, n) assert( 1 )
+#endif
 
-/*
-** When the core wants to do a query, it create a cursor using a
-** call to xOpen.  This structure is an instance of a cursor.  It
-** is destroyed by xClose.
-*/
-typedef struct fulltext_cursor {
-  sqlite3_vtab_cursor base;        /* Base class used by SQLite core */
-  QueryType iCursorType;           /* Copy of sqlite3_index_info.idxNum */
-  sqlite3_stmt *pStmt;             /* Prepared statement in use by the cursor */
-  int eof;                         /* True if at End Of Results */
-  Query q;                         /* Parsed query string */
-  Snippet snippet;                 /* Cached snippet for the current row */
-  int iColumn;                     /* Column being searched */
-  DataBuffer result;               /* Doclist results from fulltextQuery */
-  DLReader reader;                 /* Result reader if result not empty */
-} fulltext_cursor;
+/* Flush the current leaf node to %_segments, and adding the resulting
+** blockid and the starting term to the interior node which will
+** contain it.
+*/
+static int leafWriterInternalFlush(fulltext_vtab *v, LeafWriter *pWriter,
+                                   int iData, int nData){
+  sqlite_int64 iBlockid = 0;
+  const char *pStartingTerm;
+  int nStartingTerm, rc, n;
 
-static struct fulltext_vtab *cursor_vtab(fulltext_cursor *c){
-  return (fulltext_vtab *) c->base.pVtab;
-}
+  /* Must have the leading varint(0) flag, plus at least some
+  ** valid-looking data.
+  */
+  assert( nData>2 );
+  assert( iData>=0 );
+  assert( iData+nData<=pWriter->data.nData );
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData+iData, nData);
 
-static const sqlite3_module fts3Module;   /* forward declaration */
+  rc = block_insert(v, pWriter->data.pData+iData, nData, &iBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+  assert( iBlockid!=0 );
 
-/* Return a dynamically generated statement of the form
- *   insert into %_content (docid, ...) values (?, ...)
- */
-static const char *contentInsertStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  int i;
+  /* Reconstruct the first term in the leaf for purposes of building
+  ** the interior node.
+  */
+  n = fts3GetVarint32(pWriter->data.pData+iData+1, &nStartingTerm);
+  pStartingTerm = pWriter->data.pData+iData+1+n;
+  assert( pWriter->data.nData>iData+1+n+nStartingTerm );
+  assert( pWriter->nTermDistinct>0 );
+  assert( pWriter->nTermDistinct<=nStartingTerm );
+  nStartingTerm = pWriter->nTermDistinct;
 
-  initStringBuffer(&sb);
-  append(&sb, "insert into %_content (docid, ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, ") values (?");
-  for(i=0; i<v->nColumn; ++i)
-    append(&sb, ", ?");
-  append(&sb, ")");
-  return stringBufferData(&sb);
-}
+  if( pWriter->has_parent ){
+    interiorWriterAppend(&pWriter->parentWriter,
+                         pStartingTerm, nStartingTerm, iBlockid);
+  }else{
+    interiorWriterInit(1, pStartingTerm, nStartingTerm, iBlockid,
+                       &pWriter->parentWriter);
+    pWriter->has_parent = 1;
+  }
 
-/* Return a dynamically generated statement of the form
- *   select <content columns> from %_content where docid = ?
- */
-static const char *contentSelectStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  initStringBuffer(&sb);
-  append(&sb, "SELECT ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, " FROM %_content WHERE docid = ?");
-  return stringBufferData(&sb);
+  /* Track the span of this segment's leaf nodes. */
+  if( pWriter->iEndBlockid==0 ){
+    pWriter->iEndBlockid = pWriter->iStartBlockid = iBlockid;
+  }else{
+    pWriter->iEndBlockid++;
+    assert( iBlockid==pWriter->iEndBlockid );
+  }
+
+  return SQLITE_OK;
 }
+static int leafWriterFlush(fulltext_vtab *v, LeafWriter *pWriter){
+  int rc = leafWriterInternalFlush(v, pWriter, 0, pWriter->data.nData);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* Return a dynamically generated statement of the form
- *   update %_content set [col_0] = ?, [col_1] = ?, ...
- *                    where docid = ?
- */
-static const char *contentUpdateStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  int i;
+  /* Re-initialize the output buffer. */
+  dataBufferReset(&pWriter->data);
 
-  initStringBuffer(&sb);
-  append(&sb, "update %_content set ");
-  for(i=0; i<v->nColumn; ++i) {
-    if( i>0 ){
-      append(&sb, ", ");
-    }
-    append(&sb, v->azContentColumn[i]);
-    append(&sb, " = ?");
-  }
-  append(&sb, " where docid = ?");
-  return stringBufferData(&sb);
+  return SQLITE_OK;
 }
 
-/* Puts a freshly-prepared statement determined by iStmt in *ppStmt.
-** If the indicated statement has never been prepared, it is prepared
-** and cached, otherwise the cached version is reset.
+/* Fetch the root info for the segment.  If the entire leaf fits
+** within ROOT_MAX, then it will be returned directly, otherwise it
+** will be flushed and the root info will be returned from the
+** interior node.  *piEndBlockid is set to the blockid of the last
+** interior or leaf node written to disk (0 if none are written at
+** all).
 */
-static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt,
-                             sqlite3_stmt **ppStmt){
-  assert( iStmt<MAX_STMT );
-  if( v->pFulltextStatements[iStmt]==NULL ){
-    const char *zStmt;
-    int rc;
-    switch( iStmt ){
-      case CONTENT_INSERT_STMT:
-        zStmt = contentInsertStatement(v); break;
-      case CONTENT_SELECT_STMT:
-        zStmt = contentSelectStatement(v); break;
-      case CONTENT_UPDATE_STMT:
-        zStmt = contentUpdateStatement(v); break;
-      default:
-        zStmt = fulltext_zStatement[iStmt];
-    }
-    rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt],
-                         zStmt);
-    if( zStmt != fulltext_zStatement[iStmt]) sqlite3_free((void *) zStmt);
-    if( rc!=SQLITE_OK ) return rc;
-  } else {
-    int rc = sqlite3_reset(v->pFulltextStatements[iStmt]);
+static int leafWriterRootInfo(fulltext_vtab *v, LeafWriter *pWriter,
+                              char **ppRootInfo, int *pnRootInfo,
+                              sqlite_int64 *piEndBlockid){
+  /* we can fit the segment entirely inline */
+  if( !pWriter->has_parent && pWriter->data.nData<ROOT_MAX ){
+    *ppRootInfo = pWriter->data.pData;
+    *pnRootInfo = pWriter->data.nData;
+    *piEndBlockid = 0;
+    return SQLITE_OK;
+  }
+
+  /* Flush remaining leaf data. */
+  if( pWriter->data.nData>0 ){
+    int rc = leafWriterFlush(v, pWriter);
     if( rc!=SQLITE_OK ) return rc;
   }
 
-  *ppStmt = v->pFulltextStatements[iStmt];
-  return SQLITE_OK;
+  /* We must have flushed a leaf at some point. */
+  assert( pWriter->has_parent );
+
+  /* Tenatively set the end leaf blockid as the end blockid.  If the
+  ** interior node can be returned inline, this will be the final
+  ** blockid, otherwise it will be overwritten by
+  ** interiorWriterRootInfo().
+  */
+  *piEndBlockid = pWriter->iEndBlockid;
+
+  return interiorWriterRootInfo(v, &pWriter->parentWriter,
+                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/* Like sqlite3_step(), but convert SQLITE_DONE to SQLITE_OK and
-** SQLITE_ROW to SQLITE_ERROR.  Useful for statements like UPDATE,
-** where we expect no results.
+/* Collect the rootInfo data and store it into the segment directory.
+** This has the effect of flushing the segment's leaf data to
+** %_segments, and also flushing any interior nodes to %_segments.
 */
-static int sql_single_step(sqlite3_stmt *s){
-  int rc = sqlite3_step(s);
-  return (rc==SQLITE_DONE) ? SQLITE_OK : rc;
+static int leafWriterFinalize(fulltext_vtab *v, LeafWriter *pWriter){
+  sqlite_int64 iEndBlockid;
+  char *pRootInfo;
+  int rc, nRootInfo;
+
+  rc = leafWriterRootInfo(v, pWriter, &pRootInfo, &nRootInfo, &iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  /* Don't bother storing an entirely empty segment. */
+  if( iEndBlockid==0 && nRootInfo==0 ) return SQLITE_OK;
+
+  return segdir_set(v, pWriter->iLevel, pWriter->idx,
+                    pWriter->iStartBlockid, pWriter->iEndBlockid,
+                    iEndBlockid, pRootInfo, nRootInfo);
 }
 
-/* Like sql_get_statement(), but for special replicated LEAF_SELECT
-** statements.
-*/
-/* TODO(shess) Write version for generic statements and then share
-** that between the cached-statement functions.
+static void leafWriterDestroy(LeafWriter *pWriter){
+  if( pWriter->has_parent ) interiorWriterDestroy(&pWriter->parentWriter);
+  dataBufferDestroy(&pWriter->term);
+  dataBufferDestroy(&pWriter->data);
+}
+
+/* Encode a term into the leafWriter, delta-encoding as appropriate.
+** Returns the length of the new term which distinguishes it from the
+** previous term, which can be used to set nTermDistinct when a node
+** boundary is crossed.
 */
-static int sql_get_leaf_statement(fulltext_vtab *v, int idx,
-                                  sqlite3_stmt **ppStmt){
-  assert( idx>=0 && idx<MERGE_COUNT );
-  if( v->pLeafSelectStmts[idx]==NULL ){
-    int rc = sql_prepare(v->db, v->zDb, v->zName, &v->pLeafSelectStmts[idx],
-                         LEAF_SELECT);
-    if( rc!=SQLITE_OK ) return rc;
+static int leafWriterEncodeTerm(LeafWriter *pWriter,
+                                const char *pTerm, int nTerm){
+  char c[VARINT_MAX+VARINT_MAX];
+  int n, nPrefix = 0;
+
+  assert( nTerm>0 );
+  while( nPrefix<pWriter->term.nData &&
+         pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
+    nPrefix++;
+    /* Failing this implies that the terms weren't in order. */
+    assert( nPrefix<nTerm );
+  }
+
+  if( pWriter->data.nData==0 ){
+    /* Encode the node header and leading term as:
+    **  varint(0)
+    **  varint(nTerm)
+    **  char pTerm[nTerm]
+    */
+    n = fts3PutVarint(c, '\0');
+    n += fts3PutVarint(c+n, nTerm);
+    dataBufferAppend2(&pWriter->data, c, n, pTerm, nTerm);
   }else{
-    int rc = sqlite3_reset(v->pLeafSelectStmts[idx]);
-    if( rc!=SQLITE_OK ) return rc;
+    /* Delta-encode the term as:
+    **  varint(nPrefix)
+    **  varint(nSuffix)
+    **  char pTermSuffix[nSuffix]
+    */
+    n = fts3PutVarint(c, nPrefix);
+    n += fts3PutVarint(c+n, nTerm-nPrefix);
+    dataBufferAppend2(&pWriter->data, c, n, pTerm+nPrefix, nTerm-nPrefix);
   }
+  dataBufferReplace(&pWriter->term, pTerm, nTerm);
 
-  *ppStmt = v->pLeafSelectStmts[idx];
-  return SQLITE_OK;
+  return nPrefix+1;
 }
 
-/* insert into %_content (docid, ...) values ([docid], [pValues])
-** If the docid contains SQL NULL, then a unique docid will be
-** generated.
+/* Used to avoid a memmove when a large amount of doclist data is in
+** the buffer.  This constructs a node and term header before
+** iDoclistData and flushes the resulting complete node using
+** leafWriterInternalFlush().
 */
-static int content_insert(fulltext_vtab *v, sqlite3_value *docid,
-                          sqlite3_value **pValues){
-  sqlite3_stmt *s;
-  int i;
-  int rc = sql_get_statement(v, CONTENT_INSERT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static int leafWriterInlineFlush(fulltext_vtab *v, LeafWriter *pWriter,
+                                 const char *pTerm, int nTerm,
+                                 int iDoclistData){
+  char c[VARINT_MAX+VARINT_MAX];
+  int iData, n = fts3PutVarint(c, 0);
+  n += fts3PutVarint(c+n, nTerm);
 
-  rc = sqlite3_bind_value(s, 1, docid);
-  if( rc!=SQLITE_OK ) return rc;
+  /* There should always be room for the header.  Even if pTerm shared
+  ** a substantial prefix with the previous term, the entire prefix
+  ** could be constructed from earlier data in the doclist, so there
+  ** should be room.
+  */
+  assert( iDoclistData>=n+nTerm );
 
-  for(i=0; i<v->nColumn; ++i){
-    rc = sqlite3_bind_value(s, 2+i, pValues[i]);
-    if( rc!=SQLITE_OK ) return rc;
-  }
+  iData = iDoclistData-(n+nTerm);
+  memcpy(pWriter->data.pData+iData, c, n);
+  memcpy(pWriter->data.pData+iData+n, pTerm, nTerm);
 
-  return sql_single_step(s);
+  return leafWriterInternalFlush(v, pWriter, iData, pWriter->data.nData-iData);
 }
 
-/* update %_content set col0 = pValues[0], col1 = pValues[1], ...
- *                  where docid = [iDocid] */
-static int content_update(fulltext_vtab *v, sqlite3_value **pValues,
-                          sqlite_int64 iDocid){
-  sqlite3_stmt *s;
-  int i;
-  int rc = sql_get_statement(v, CONTENT_UPDATE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
+** %_segments.
+*/
+static int leafWriterStepMerge(fulltext_vtab *v, LeafWriter *pWriter,
+                               const char *pTerm, int nTerm,
+                               DLReader *pReaders, int nReaders){
+  char c[VARINT_MAX+VARINT_MAX];
+  int iTermData = pWriter->data.nData, iDoclistData;
+  int i, nData, n, nActualData, nActual, rc, nTermDistinct;
 
-  for(i=0; i<v->nColumn; ++i){
-    rc = sqlite3_bind_value(s, 1+i, pValues[i]);
-    if( rc!=SQLITE_OK ) return rc;
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
+  nTermDistinct = leafWriterEncodeTerm(pWriter, pTerm, nTerm);
+
+  /* Remember nTermDistinct if opening a new node. */
+  if( iTermData==0 ) pWriter->nTermDistinct = nTermDistinct;
+
+  iDoclistData = pWriter->data.nData;
+
+  /* Estimate the length of the merged doclist so we can leave space
+  ** to encode it.
+  */
+  for(i=0, nData=0; i<nReaders; i++){
+    nData += dlrAllDataBytes(&pReaders[i]);
   }
+  n = fts3PutVarint(c, nData);
+  dataBufferAppend(&pWriter->data, c, n);
 
-  rc = sqlite3_bind_int64(s, 1+v->nColumn, iDocid);
-  if( rc!=SQLITE_OK ) return rc;
+  docListMerge(&pWriter->data, pReaders, nReaders);
+  ASSERT_VALID_DOCLIST(DL_DEFAULT,
+                       pWriter->data.pData+iDoclistData+n,
+                       pWriter->data.nData-iDoclistData-n, NULL);
 
-  return sql_single_step(s);
-}
+  /* The actual amount of doclist data at this point could be smaller
+  ** than the length we encoded.  Additionally, the space required to
+  ** encode this length could be smaller.  For small doclists, this is
+  ** not a big deal, we can just use memmove() to adjust things.
+  */
+  nActualData = pWriter->data.nData-(iDoclistData+n);
+  nActual = fts3PutVarint(c, nActualData);
+  assert( nActualData<=nData );
+  assert( nActual<=n );
 
-static void freeStringArray(int nString, const char **pString){
-  int i;
+  /* If the new doclist is big enough for force a standalone leaf
+  ** node, we can immediately flush it inline without doing the
+  ** memmove().
+  */
+  /* TODO(shess) This test matches leafWriterStep(), which does this
+  ** test before it knows the cost to varint-encode the term and
+  ** doclist lengths.  At some point, change to
+  ** pWriter->data.nData-iTermData>STANDALONE_MIN.
+  */
+  if( nTerm+nActualData>STANDALONE_MIN ){
+    /* Push leaf node from before this term. */
+    if( iTermData>0 ){
+      rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
+      if( rc!=SQLITE_OK ) return rc;
 
-  for (i=0 ; i < nString ; ++i) {
-    if( pString[i]!=NULL ) sqlite3_free((void *) pString[i]);
+      pWriter->nTermDistinct = nTermDistinct;
+    }
+
+    /* Fix the encoded doclist length. */
+    iDoclistData += n - nActual;
+    memcpy(pWriter->data.pData+iDoclistData, c, nActual);
+
+    /* Push the standalone leaf node. */
+    rc = leafWriterInlineFlush(v, pWriter, pTerm, nTerm, iDoclistData);
+    if( rc!=SQLITE_OK ) return rc;
+
+    /* Leave the node empty. */
+    dataBufferReset(&pWriter->data);
+
+    return rc;
   }
-  sqlite3_free((void *) pString);
-}
 
-/* select * from %_content where docid = [iDocid]
- * The caller must delete the returned array and all strings in it.
- * null fields will be NULL in the returned array.
- *
- * TODO: Perhaps we should return pointer/length strings here for consistency
- * with other code which uses pointer/length. */
-static int content_select(fulltext_vtab *v, sqlite_int64 iDocid,
-                          const char ***pValues){
-  sqlite3_stmt *s;
-  const char **values;
-  int i;
-  int rc;
+  /* At this point, we know that the doclist was small, so do the
+  ** memmove if indicated.
+  */
+  if( nActual<n ){
+    memmove(pWriter->data.pData+iDoclistData+nActual,
+            pWriter->data.pData+iDoclistData+n,
+            pWriter->data.nData-(iDoclistData+n));
+    pWriter->data.nData -= n-nActual;
+  }
 
-  *pValues = NULL;
+  /* Replace written length with actual length. */
+  memcpy(pWriter->data.pData+iDoclistData, c, nActual);
 
-  rc = sql_get_statement(v, CONTENT_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+  /* If the node is too large, break things up. */
+  /* TODO(shess) This test matches leafWriterStep(), which does this
+  ** test before it knows the cost to varint-encode the term and
+  ** doclist lengths.  At some point, change to
+  ** pWriter->data.nData>LEAF_MAX.
+  */
+  if( iTermData+nTerm+nActualData>LEAF_MAX ){
+    /* Flush out the leading data as a node */
+    rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
+    if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_int64(s, 1, iDocid);
-  if( rc!=SQLITE_OK ) return rc;
+    pWriter->nTermDistinct = nTermDistinct;
 
-  rc = sqlite3_step(s);
-  if( rc!=SQLITE_ROW ) return rc;
+    /* Rebuild header using the current term */
+    n = fts3PutVarint(pWriter->data.pData, 0);
+    n += fts3PutVarint(pWriter->data.pData+n, nTerm);
+    memcpy(pWriter->data.pData+n, pTerm, nTerm);
+    n += nTerm;
 
-  values = (const char **) sqlite3_malloc(v->nColumn * sizeof(const char *));
-  for(i=0; i<v->nColumn; ++i){
-    if( sqlite3_column_type(s, i)==SQLITE_NULL ){
-      values[i] = NULL;
-    }else{
-      values[i] = string_dup((char*)sqlite3_column_text(s, i));
-    }
+    /* There should always be room, because the previous encoding
+    ** included all data necessary to construct the term.
+    */
+    assert( n<iDoclistData );
+    /* So long as STANDALONE_MIN is half or less of LEAF_MAX, the
+    ** following memcpy() is safe (as opposed to needing a memmove).
+    */
+    assert( 2*STANDALONE_MIN<=LEAF_MAX );
+    assert( n+pWriter->data.nData-iDoclistData<iDoclistData );
+    memcpy(pWriter->data.pData+n,
+           pWriter->data.pData+iDoclistData,
+           pWriter->data.nData-iDoclistData);
+    pWriter->data.nData -= iDoclistData-n;
   }
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
 
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ){
-    *pValues = values;
-    return SQLITE_OK;
-  }
+  return SQLITE_OK;
+}
+
+/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
+** %_segments.
+*/
+/* TODO(shess) Revise writeZeroSegment() so that doclists are
+** constructed directly in pWriter->data.
+*/
+static int leafWriterStep(fulltext_vtab *v, LeafWriter *pWriter,
+                          const char *pTerm, int nTerm,
+                          const char *pData, int nData){
+  int rc;
+  DLReader reader;
+
+  dlrInit(&reader, DL_DEFAULT, pData, nData);
+  rc = leafWriterStepMerge(v, pWriter, pTerm, nTerm, &reader, 1);
+  dlrDestroy(&reader);
 
-  freeStringArray(v->nColumn, values);
   return rc;
 }
 
-/* delete from %_content where docid = [iDocid ] */
-static int content_delete(fulltext_vtab *v, sqlite_int64 iDocid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, CONTENT_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_int64(s, 1, iDocid);
-  if( rc!=SQLITE_OK ) return rc;
+/****************************************************************/
+/* LeafReader is used to iterate over an individual leaf node. */
+typedef struct LeafReader {
+  DataBuffer term;          /* copy of current term. */
 
-  return sql_single_step(s);
-}
+  const char *pData;        /* data for current term. */
+  int nData;
+} LeafReader;
 
-/* insert into %_segments values ([pData])
-**   returns assigned blockid in *piBlockid
-*/
-static int block_insert(fulltext_vtab *v, const char *pData, int nData,
-                        sqlite_int64 *piBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, BLOCK_INSERT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static void leafReaderDestroy(LeafReader *pReader){
+  dataBufferDestroy(&pReader->term);
+  SCRAMBLE(pReader);
+}
 
-  rc = sqlite3_bind_blob(s, 1, pData, nData, SQLITE_STATIC);
-  if( rc!=SQLITE_OK ) return rc;
+static int leafReaderAtEnd(LeafReader *pReader){
+  return pReader->nData<=0;
+}
 
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
+/* Access the current term. */
+static int leafReaderTermBytes(LeafReader *pReader){
+  return pReader->term.nData;
+}
+static const char *leafReaderTerm(LeafReader *pReader){
+  assert( pReader->term.nData>0 );
+  return pReader->term.pData;
+}
 
-  /* blockid column is an alias for rowid. */
-  *piBlockid = sqlite3_last_insert_rowid(v->db);
-  return SQLITE_OK;
+/* Access the doclist data for the current term. */
+static int leafReaderDataBytes(LeafReader *pReader){
+  int nData;
+  assert( pReader->term.nData>0 );
+  fts3GetVarint32(pReader->pData, &nData);
+  return nData;
+}
+static const char *leafReaderData(LeafReader *pReader){
+  int n, nData;
+  assert( pReader->term.nData>0 );
+  n = fts3GetVarint32(pReader->pData, &nData);
+  return pReader->pData+n;
 }
 
-/* delete from %_segments
-**   where blockid between [iStartBlockid] and [iEndBlockid]
-**
-** Deletes the range of blocks, inclusive, used to delete the blocks
-** which form a segment.
-*/
-static int block_delete(fulltext_vtab *v,
-                        sqlite_int64 iStartBlockid, sqlite_int64 iEndBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, BLOCK_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static void leafReaderInit(const char *pData, int nData,
+                           LeafReader *pReader){
+  int nTerm, n;
+
+  assert( nData>0 );
+  assert( pData[0]=='\0' );
 
-  rc = sqlite3_bind_int64(s, 1, iStartBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  CLEAR(pReader);
 
-  rc = sqlite3_bind_int64(s, 2, iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Read the first term, skipping the header byte. */
+  n = fts3GetVarint32(pData+1, &nTerm);
+  dataBufferInit(&pReader->term, nTerm);
+  dataBufferReplace(&pReader->term, pData+1+n, nTerm);
 
-  return sql_single_step(s);
+  /* Position after the first term. */
+  assert( 1+n+nTerm<nData );
+  pReader->pData = pData+1+n+nTerm;
+  pReader->nData = nData-1-n-nTerm;
 }
 
-/* Returns SQLITE_ROW with *pidx set to the maximum segment idx found
-** at iLevel.  Returns SQLITE_DONE if there are no segments at
-** iLevel.  Otherwise returns an error.
-*/
-static int segdir_max_index(fulltext_vtab *v, int iLevel, int *pidx){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_MAX_INDEX_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/* Step the reader forward to the next term. */
+static void leafReaderStep(LeafReader *pReader){
+  int n, nData, nPrefix, nSuffix;
+  assert( !leafReaderAtEnd(pReader) );
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Skip previous entry's data block. */
+  n = fts3GetVarint32(pReader->pData, &nData);
+  assert( n+nData<=pReader->nData );
+  pReader->pData += n+nData;
+  pReader->nData -= n+nData;
 
-  rc = sqlite3_step(s);
-  /* Should always get at least one row due to how max() works. */
-  if( rc==SQLITE_DONE ) return SQLITE_DONE;
-  if( rc!=SQLITE_ROW ) return rc;
+  if( !leafReaderAtEnd(pReader) ){
+    /* Construct the new term using a prefix from the old term plus a
+    ** suffix from the leaf data.
+    */
+    n = fts3GetVarint32(pReader->pData, &nPrefix);
+    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
+    assert( n+nSuffix<pReader->nData );
+    pReader->term.nData = nPrefix;
+    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
 
-  /* NULL means that there were no inputs to max(). */
-  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
-    rc = sqlite3_step(s);
-    if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-    return rc;
+    pReader->pData += n+nSuffix;
+    pReader->nData -= n+nSuffix;
   }
-
-  *pidx = sqlite3_column_int(s, 0);
-
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
-  return SQLITE_ROW;
 }
 
-/* insert into %_segdir values (
-**   [iLevel], [idx],
-**   [iStartBlockid], [iLeavesEndBlockid], [iEndBlockid],
-**   [pRootData]
-** )
+/* strcmp-style comparison of pReader's current term against pTerm.
+** If isPrefix, equality means equal through nTerm bytes.
 */
-static int segdir_set(fulltext_vtab *v, int iLevel, int idx,
-                      sqlite_int64 iStartBlockid,
-                      sqlite_int64 iLeavesEndBlockid,
-                      sqlite_int64 iEndBlockid,
-                      const char *pRootData, int nRootData){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SET_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+static int leafReaderTermCmp(LeafReader *pReader,
+                             const char *pTerm, int nTerm, int isPrefix){
+  int c, n = pReader->term.nData<nTerm ? pReader->term.nData : nTerm;
+  if( n==0 ){
+    if( pReader->term.nData>0 ) return -1;
+    if(nTerm>0 ) return 1;
+    return 0;
+  }
 
-  rc = sqlite3_bind_int(s, 2, idx);
-  if( rc!=SQLITE_OK ) return rc;
+  c = memcmp(pReader->term.pData, pTerm, n);
+  if( c!=0 ) return c;
+  if( isPrefix && n==nTerm ) return 0;
+  return pReader->term.nData - nTerm;
+}
 
-  rc = sqlite3_bind_int64(s, 3, iStartBlockid);
-  if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_int64(s, 4, iLeavesEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+/****************************************************************/
+/* LeavesReader wraps LeafReader to allow iterating over the entire
+** leaf layer of the tree.
+*/
+typedef struct LeavesReader {
+  int idx;                  /* Index within the segment. */
 
-  rc = sqlite3_bind_int64(s, 5, iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  sqlite3_stmt *pStmt;      /* Statement we're streaming leaves from. */
+  int eof;                  /* we've seen SQLITE_DONE from pStmt. */
 
-  rc = sqlite3_bind_blob(s, 6, pRootData, nRootData, SQLITE_STATIC);
-  if( rc!=SQLITE_OK ) return rc;
+  LeafReader leafReader;    /* reader for the current leaf. */
+  DataBuffer rootData;      /* root data for inline. */
+} LeavesReader;
 
-  return sql_single_step(s);
+/* Access the current term. */
+static int leavesReaderTermBytes(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderTermBytes(&pReader->leafReader);
+}
+static const char *leavesReaderTerm(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderTerm(&pReader->leafReader);
 }
 
-/* Queries %_segdir for the block span of the segments in level
-** iLevel.  Returns SQLITE_DONE if there are no blocks for iLevel,
-** SQLITE_ROW if there are blocks, else an error.
-*/
-static int segdir_span(fulltext_vtab *v, int iLevel,
-                       sqlite_int64 *piStartBlockid,
-                       sqlite_int64 *piEndBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SPAN_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/* Access the doclist data for the current term. */
+static int leavesReaderDataBytes(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderDataBytes(&pReader->leafReader);
+}
+static const char *leavesReaderData(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderData(&pReader->leafReader);
+}
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+static int leavesReaderAtEnd(LeavesReader *pReader){
+  return pReader->eof;
+}
 
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ) return SQLITE_DONE;  /* Should never happen */
-  if( rc!=SQLITE_ROW ) return rc;
+/* loadSegmentLeaves() may not read all the way to SQLITE_DONE, thus
+** leaving the statement handle open, which locks the table.
+*/
+/* TODO(shess) This "solution" is not satisfactory.  Really, there
+** should be check-in function for all statement handles which
+** arranges to call sqlite3_reset().  This most likely will require
+** modification to control flow all over the place, though, so for now
+** just punt.
+**
+** Note the the current system assumes that segment merges will run to
+** completion, which is why this particular probably hasn't arisen in
+** this case.  Probably a brittle assumption.
+*/
+static int leavesReaderReset(LeavesReader *pReader){
+  return sqlite3_reset(pReader->pStmt);
+}
 
-  /* This happens if all segments at this level are entirely inline. */
-  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
-    /* We expect only one row.  We must execute another sqlite3_step()
-     * to complete the iteration; otherwise the table will remain locked. */
-    int rc2 = sqlite3_step(s);
-    if( rc2==SQLITE_ROW ) return SQLITE_ERROR;
-    return rc2;
+static void leavesReaderDestroy(LeavesReader *pReader){
+  /* If idx is -1, that means we're using a non-cached statement
+  ** handle in the optimize() case, so we need to release it.
+  */
+  if( pReader->pStmt!=NULL && pReader->idx==-1 ){
+    sqlite3_finalize(pReader->pStmt);
   }
-
-  *piStartBlockid = sqlite3_column_int64(s, 0);
-  *piEndBlockid = sqlite3_column_int64(s, 1);
-
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
-  return SQLITE_ROW;
+  leafReaderDestroy(&pReader->leafReader);
+  dataBufferDestroy(&pReader->rootData);
+  SCRAMBLE(pReader);
 }
 
-/* Delete the segment blocks and segment directory records for all
-** segments at iLevel.
+/* Initialize pReader with the given root data (if iStartBlockid==0
+** the leaf data was entirely contained in the root), or from the
+** stream of blocks between iStartBlockid and iEndBlockid, inclusive.
 */
-static int segdir_delete(fulltext_vtab *v, int iLevel){
-  sqlite3_stmt *s;
-  sqlite_int64 iStartBlockid, iEndBlockid;
-  int rc = segdir_span(v, iLevel, &iStartBlockid, &iEndBlockid);
-  if( rc!=SQLITE_ROW && rc!=SQLITE_DONE ) return rc;
+static int leavesReaderInit(fulltext_vtab *v,
+                            int idx,
+                            sqlite_int64 iStartBlockid,
+                            sqlite_int64 iEndBlockid,
+                            const char *pRootData, int nRootData,
+                            LeavesReader *pReader){
+  CLEAR(pReader);
+  pReader->idx = idx;
 
-  if( rc==SQLITE_ROW ){
-    rc = block_delete(v, iStartBlockid, iEndBlockid);
+  dataBufferInit(&pReader->rootData, 0);
+  if( iStartBlockid==0 ){
+    /* Entire leaf level fit in root data. */
+    dataBufferReplace(&pReader->rootData, pRootData, nRootData);
+    leafReaderInit(pReader->rootData.pData, pReader->rootData.nData,
+                   &pReader->leafReader);
+  }else{
+    sqlite3_stmt *s;
+    int rc = sql_get_leaf_statement(v, idx, &s);
     if( rc!=SQLITE_OK ) return rc;
-  }
 
-  /* Delete the segment directory itself. */
-  rc = sql_get_statement(v, SEGDIR_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+    rc = sqlite3_bind_int64(s, 1, iStartBlockid);
+    if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_int64(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+    rc = sqlite3_bind_int64(s, 2, iEndBlockid);
+    if( rc!=SQLITE_OK ) return rc;
 
-  return sql_single_step(s);
-}
+    rc = sqlite3_step(s);
+    if( rc==SQLITE_DONE ){
+      pReader->eof = 1;
+      return SQLITE_OK;
+    }
+    if( rc!=SQLITE_ROW ) return rc;
 
-/* TODO(shess) clearPendingTerms() is far down the file because
-** writeZeroSegment() is far down the file because LeafWriter is far
-** down the file.  Consider refactoring the code to move the non-vtab
-** code above the vtab code so that we don't need this forward
-** reference.
-*/
-static int clearPendingTerms(fulltext_vtab *v);
+    pReader->pStmt = s;
+    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
+                   sqlite3_column_bytes(pReader->pStmt, 0),
+                   &pReader->leafReader);
+  }
+  return SQLITE_OK;
+}
 
-/*
-** Free the memory used to contain a fulltext_vtab structure.
+/* Step the current leaf forward to the next term.  If we reach the
+** end of the current leaf, step forward to the next leaf block.
 */
-static void fulltext_vtab_destroy(fulltext_vtab *v){
-  int iStmt, i;
+static int leavesReaderStep(fulltext_vtab *v, LeavesReader *pReader){
+  assert( !leavesReaderAtEnd(pReader) );
+  leafReaderStep(&pReader->leafReader);
 
-  FTSTRACE(("FTS3 Destroy %p\n", v));
-  for( iStmt=0; iStmt<MAX_STMT; iStmt++ ){
-    if( v->pFulltextStatements[iStmt]!=NULL ){
-      sqlite3_finalize(v->pFulltextStatements[iStmt]);
-      v->pFulltextStatements[iStmt] = NULL;
+  if( leafReaderAtEnd(&pReader->leafReader) ){
+    int rc;
+    if( pReader->rootData.pData ){
+      pReader->eof = 1;
+      return SQLITE_OK;
     }
-  }
-
-  for( i=0; i<MERGE_COUNT; i++ ){
-    if( v->pLeafSelectStmts[i]!=NULL ){
-      sqlite3_finalize(v->pLeafSelectStmts[i]);
-      v->pLeafSelectStmts[i] = NULL;
+    rc = sqlite3_step(pReader->pStmt);
+    if( rc!=SQLITE_ROW ){
+      pReader->eof = 1;
+      return rc==SQLITE_DONE ? SQLITE_OK : rc;
     }
+    leafReaderDestroy(&pReader->leafReader);
+    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
+                   sqlite3_column_bytes(pReader->pStmt, 0),
+                   &pReader->leafReader);
   }
+  return SQLITE_OK;
+}
 
-  if( v->pTokenizer!=NULL ){
-    v->pTokenizer->pModule->xDestroy(v->pTokenizer);
-    v->pTokenizer = NULL;
+/* Order LeavesReaders by their term, ignoring idx.  Readers at eof
+** always sort to the end.
+*/
+static int leavesReaderTermCmp(LeavesReader *lr1, LeavesReader *lr2){
+  if( leavesReaderAtEnd(lr1) ){
+    if( leavesReaderAtEnd(lr2) ) return 0;
+    return 1;
   }
+  if( leavesReaderAtEnd(lr2) ) return -1;
 
-  clearPendingTerms(v);
-
-  sqlite3_free(v->azColumn);
-  for(i = 0; i < v->nColumn; ++i) {
-    sqlite3_free(v->azContentColumn[i]);
-  }
-  sqlite3_free(v->azContentColumn);
-  sqlite3_free(v);
+  return leafReaderTermCmp(&lr1->leafReader,
+                           leavesReaderTerm(lr2), leavesReaderTermBytes(lr2),
+                           0);
 }
 
-/*
-** Token types for parsing the arguments to xConnect or xCreate.
-*/
-#define TOKEN_EOF         0    /* End of file */
-#define TOKEN_SPACE       1    /* Any kind of whitespace */
-#define TOKEN_ID          2    /* An identifier */
-#define TOKEN_STRING      3    /* A string literal */
-#define TOKEN_PUNCT       4    /* A single punctuation character */
-
-/*
-** If X is a character that can be used in an identifier then
-** ftsIdChar(X) will be true.  Otherwise it is false.
-**
-** For ASCII, any character with the high-order bit set is
-** allowed in an identifier.  For 7-bit characters, 
-** isFtsIdChar[X] must be 1.
-**
-** Ticket #1066.  the SQL standard does not allow '$' in the
-** middle of identfiers.  But many SQL implementations do. 
-** SQLite will allow '$' in identifiers for compatibility.
-** But the feature is undocumented.
+/* Similar to leavesReaderTermCmp(), with additional ordering by idx
+** so that older segments sort before newer segments.
 */
-static const char isFtsIdChar[] = {
-/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
-    0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* 2x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
-};
-#define ftsIdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && isFtsIdChar[c-0x20]))
-
+static int leavesReaderCmp(LeavesReader *lr1, LeavesReader *lr2){
+  int c = leavesReaderTermCmp(lr1, lr2);
+  if( c!=0 ) return c;
+  return lr1->idx-lr2->idx;
+}
 
-/*
-** Return the length of the token that begins at z[0]. 
-** Store the token type in *tokenType before returning.
+/* Assume that pLr[1]..pLr[nLr] are sorted.  Bubble pLr[0] into its
+** sorted position.
 */
-static int ftsGetToken(const char *z, int *tokenType){
-  int i, c;
-  switch( *z ){
-    case 0: {
-      *tokenType = TOKEN_EOF;
-      return 0;
-    }
-    case ' ': case '\t': case '\n': case '\f': case '\r': {
-      for(i=1; safe_isspace(z[i]); i++){}
-      *tokenType = TOKEN_SPACE;
-      return i;
-    }
-    case '`':
-    case '\'':
-    case '"': {
-      int delim = z[0];
-      for(i=1; (c=z[i])!=0; i++){
-        if( c==delim ){
-          if( z[i+1]==delim ){
-            i++;
-          }else{
-            break;
-          }
-        }
-      }
-      *tokenType = TOKEN_STRING;
-      return i + (c!=0);
-    }
-    case '[': {
-      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
-      *tokenType = TOKEN_ID;
-      return i;
-    }
-    default: {
-      if( !ftsIdChar(*z) ){
-        break;
-      }
-      for(i=1; ftsIdChar(z[i]); i++){}
-      *tokenType = TOKEN_ID;
-      return i;
-    }
+static void leavesReaderReorder(LeavesReader *pLr, int nLr){
+  while( nLr>1 && leavesReaderCmp(pLr, pLr+1)>0 ){
+    LeavesReader tmp = pLr[0];
+    pLr[0] = pLr[1];
+    pLr[1] = tmp;
+    nLr--;
+    pLr++;
   }
-  *tokenType = TOKEN_PUNCT;
-  return 1;
 }
 
-/*
-** A token extracted from a string is an instance of the following
-** structure.
+/* Initializes pReaders with the segments from level iLevel, returning
+** the number of segments in *piReaders.  Leaves pReaders in sorted
+** order.
 */
-typedef struct FtsToken {
-  const char *z;       /* Pointer to token text.  Not '\000' terminated */
-  short int n;         /* Length of the token text in bytes. */
-} FtsToken;
+static int leavesReadersInit(fulltext_vtab *v, int iLevel,
+                             LeavesReader *pReaders, int *piReaders){
+  sqlite3_stmt *s;
+  int i, rc = sql_get_statement(v, SEGDIR_SELECT_LEVEL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Given a input string (which is really one of the argv[] parameters
-** passed into xConnect or xCreate) split the string up into tokens.
-** Return an array of pointers to '\000' terminated strings, one string
-** for each non-whitespace token.
-**
-** The returned array is terminated by a single NULL pointer.
-**
-** Space to hold the returned array is obtained from a single
-** malloc and should be freed by passing the return value to free().
-** The individual strings within the token list are all a part of
-** the single memory allocation and will all be freed at once.
-*/
-static char **tokenizeString(const char *z, int *pnToken){
-  int nToken = 0;
-  FtsToken *aToken = sqlite3_malloc( strlen(z) * sizeof(aToken[0]) );
-  int n = 1;
-  int e, i;
-  int totalSize = 0;
-  char **azToken;
-  char *zCopy;
-  while( n>0 ){
-    n = ftsGetToken(z, &e);
-    if( e!=TOKEN_SPACE ){
-      aToken[nToken].z = z;
-      aToken[nToken].n = n;
-      nToken++;
-      totalSize += n+1;
-    }
-    z += n;
-  }
-  azToken = (char**)sqlite3_malloc( nToken*sizeof(char*) + totalSize );
-  zCopy = (char*)&azToken[nToken];
-  nToken--;
-  for(i=0; i<nToken; i++){
-    azToken[i] = zCopy;
-    n = aToken[i].n;
-    memcpy(zCopy, aToken[i].z, n);
-    zCopy[n] = 0;
-    zCopy += n+1;
-  }
-  azToken[nToken] = 0;
-  sqlite3_free(aToken);
-  *pnToken = nToken;
-  return azToken;
-}
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Convert an SQL-style quoted string into a normal string by removing
-** the quote characters.  The conversion is done in-place.  If the
-** input does not begin with a quote character, then this routine
-** is a no-op.
-**
-** Examples:
-**
-**     "abc"   becomes   abc
-**     'xyz'   becomes   xyz
-**     [pqr]   becomes   pqr
-**     `mno`   becomes   mno
-*/
-static void dequoteString(char *z){
-  int quote;
-  int i, j;
-  if( z==0 ) return;
-  quote = z[0];
-  switch( quote ){
-    case '\'':  break;
-    case '"':   break;
-    case '`':   break;                /* For MySQL compatibility */
-    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
-    default:    return;
+  i = 0;
+  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+    sqlite_int64 iStart = sqlite3_column_int64(s, 0);
+    sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
+    const char *pRootData = sqlite3_column_blob(s, 2);
+    int nRootData = sqlite3_column_bytes(s, 2);
+
+    assert( i<MERGE_COUNT );
+    rc = leavesReaderInit(v, i, iStart, iEnd, pRootData, nRootData,
+                          &pReaders[i]);
+    if( rc!=SQLITE_OK ) break;
+
+    i++;
   }
-  for(i=1, j=0; z[i]; i++){
-    if( z[i]==quote ){
-      if( z[i+1]==quote ){
-        z[j++] = quote;
-        i++;
-      }else{
-        z[j++] = 0;
-        break;
-      }
-    }else{
-      z[j++] = z[i];
+  if( rc!=SQLITE_DONE ){
+    while( i-->0 ){
+      leavesReaderDestroy(&pReaders[i]);
     }
+    return rc;
+  }
+
+  *piReaders = i;
+
+  /* Leave our results sorted by term, then age. */
+  while( i-- ){
+    leavesReaderReorder(pReaders+i, *piReaders-i);
   }
+  return SQLITE_OK;
 }
 
-/*
-** The input azIn is a NULL-terminated list of tokens.  Remove the first
-** token and all punctuation tokens.  Remove the quotes from
-** around string literal tokens.
-**
-** Example:
-**
-**     input:      tokenize chinese ( 'simplifed' , 'mixed' )
-**     output:     chinese simplifed mixed
-**
-** Another example:
-**
-**     input:      delimiters ( '[' , ']' , '...' )
-**     output:     [ ] ...
+/* Merge doclists from pReaders[nReaders] into a single doclist, which
+** is written to pWriter.  Assumes pReaders is ordered oldest to
+** newest.
 */
-static void tokenListToIdList(char **azIn){
-  int i, j;
-  if( azIn ){
-    for(i=0, j=-1; azIn[i]; i++){
-      if( safe_isalnum(azIn[i][0]) || azIn[i][1] ){
-        dequoteString(azIn[i]);
-        if( j>=0 ){
-          azIn[j] = azIn[i];
-        }
-        j++;
-      }
-    }
-    azIn[j] = 0;
+/* TODO(shess) Consider putting this inline in segmentMerge(). */
+static int leavesReadersMerge(fulltext_vtab *v,
+                              LeavesReader *pReaders, int nReaders,
+                              LeafWriter *pWriter){
+  DLReader dlReaders[MERGE_COUNT];
+  const char *pTerm = leavesReaderTerm(pReaders);
+  int i, nTerm = leavesReaderTermBytes(pReaders);
+
+  assert( nReaders<=MERGE_COUNT );
+
+  for(i=0; i<nReaders; i++){
+    dlrInit(&dlReaders[i], DL_DEFAULT,
+            leavesReaderData(pReaders+i),
+            leavesReaderDataBytes(pReaders+i));
   }
+
+  return leafWriterStepMerge(v, pWriter, pTerm, nTerm, dlReaders, nReaders);
 }
 
+/* Forward ref due to mutual recursion with segdirNextIndex(). */
+static int segmentMerge(fulltext_vtab *v, int iLevel);
 
-/*
-** Find the first alphanumeric token in the string zIn.  Null-terminate
-** this token.  Remove any quotation marks.  And return a pointer to
-** the result.
+/* Put the next available index at iLevel into *pidx.  If iLevel
+** already has MERGE_COUNT segments, they are merged to a higher
+** level to make room.
 */
-static char *firstToken(char *zIn, char **pzTail){
-  int n, ttype;
-  while(1){
-    n = ftsGetToken(zIn, &ttype);
-    if( ttype==TOKEN_SPACE ){
-      zIn += n;
-    }else if( ttype==TOKEN_EOF ){
-      *pzTail = zIn;
-      return 0;
+static int segdirNextIndex(fulltext_vtab *v, int iLevel, int *pidx){
+  int rc = segdir_max_index(v, iLevel, pidx);
+  if( rc==SQLITE_DONE ){              /* No segments at iLevel. */
+    *pidx = 0;
+  }else if( rc==SQLITE_ROW ){
+    if( *pidx==(MERGE_COUNT-1) ){
+      rc = segmentMerge(v, iLevel);
+      if( rc!=SQLITE_OK ) return rc;
+      *pidx = 0;
     }else{
-      zIn[n] = 0;
-      *pzTail = &zIn[1];
-      dequoteString(zIn);
-      return zIn;
+      (*pidx)++;
     }
+  }else{
+    return rc;
   }
-  /*NOTREACHED*/
+  return SQLITE_OK;
 }
 
-/* Return true if...
-**
-**   *  s begins with the string t, ignoring case
-**   *  s is longer than t
-**   *  The first character of s beyond t is not a alphanumeric
-** 
-** Ignore leading space in *s.
-**
-** To put it another way, return true if the first token of
-** s[] is t[].
+/* Merge MERGE_COUNT segments at iLevel into a new segment at
+** iLevel+1.  If iLevel+1 is already full of segments, those will be
+** merged to make room.
 */
-static int startsWith(const char *s, const char *t){
-  while( safe_isspace(*s) ){ s++; }
-  while( *t ){
-    if( safe_tolower(*s++)!=safe_tolower(*t++) ) return 0;
-  }
-  return *s!='_' && !safe_isalnum(*s);
-}
+static int segmentMerge(fulltext_vtab *v, int iLevel){
+  LeafWriter writer;
+  LeavesReader lrs[MERGE_COUNT];
+  int i, rc, idx = 0;
 
-/*
-** An instance of this structure defines the "spec" of a
-** full text index.  This structure is populated by parseSpec
-** and use by fulltextConnect and fulltextCreate.
-*/
-typedef struct TableSpec {
-  const char *zDb;         /* Logical database name */
-  const char *zName;       /* Name of the full-text index */
-  int nColumn;             /* Number of columns to be indexed */
-  char **azColumn;         /* Original names of columns to be indexed */
-  char **azContentColumn;  /* Column names for %_content */
-  char **azTokenizer;      /* Name of tokenizer and its arguments */
-} TableSpec;
+  /* Determine the next available segment index at the next level,
+  ** merging as necessary.
+  */
+  rc = segdirNextIndex(v, iLevel+1, &idx);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Reclaim all of the memory used by a TableSpec
-*/
-static void clearTableSpec(TableSpec *p) {
-  sqlite3_free(p->azColumn);
-  sqlite3_free(p->azContentColumn);
-  sqlite3_free(p->azTokenizer);
-}
+  /* TODO(shess) This assumes that we'll always see exactly
+  ** MERGE_COUNT segments to merge at a given level.  That will be
+  ** broken if we allow the developer to request preemptive or
+  ** deferred merging.
+  */
+  memset(&lrs, '\0', sizeof(lrs));
+  rc = leavesReadersInit(v, iLevel, lrs, &i);
+  if( rc!=SQLITE_OK ) return rc;
+  assert( i==MERGE_COUNT );
 
-/* Parse a CREATE VIRTUAL TABLE statement, which looks like this:
- *
- * CREATE VIRTUAL TABLE email
- *        USING fts3(subject, body, tokenize mytokenizer(myarg))
- *
- * We return parsed information in a TableSpec structure.
- * 
- */
-static int parseSpec(TableSpec *pSpec, int argc, const char *const*argv,
-                     char**pzErr){
-  int i, n;
-  char *z, *zDummy;
-  char **azArg;
-  const char *zTokenizer = 0;    /* argv[] entry describing the tokenizer */
+  leafWriterInit(iLevel+1, idx, &writer);
 
-  assert( argc>=3 );
-  /* Current interface:
-  ** argv[0] - module name
-  ** argv[1] - database name
-  ** argv[2] - table name
-  ** argv[3..] - columns, optionally followed by tokenizer specification
-  **             and snippet delimiters specification.
+  /* Since leavesReaderReorder() pushes readers at eof to the end,
+  ** when the first reader is empty, all will be empty.
   */
+  while( !leavesReaderAtEnd(lrs) ){
+    /* Figure out how many readers share their next term. */
+    for(i=1; i<MERGE_COUNT && !leavesReaderAtEnd(lrs+i); i++){
+      if( 0!=leavesReaderTermCmp(lrs, lrs+i) ) break;
+    }
 
-  /* Make a copy of the complete argv[][] array in a single allocation.
-  ** The argv[][] array is read-only and transient.  We can write to the
-  ** copy in order to modify things and the copy is persistent.
-  */
-  CLEAR(pSpec);
-  for(i=n=0; i<argc; i++){
-    n += strlen(argv[i]) + 1;
+    rc = leavesReadersMerge(v, lrs, i, &writer);
+    if( rc!=SQLITE_OK ) goto err;
+
+    /* Step forward those that were merged. */
+    while( i-->0 ){
+      rc = leavesReaderStep(v, lrs+i);
+      if( rc!=SQLITE_OK ) goto err;
+
+      /* Reorder by term, then by age. */
+      leavesReaderReorder(lrs+i, MERGE_COUNT-i);
+    }
   }
-  azArg = sqlite3_malloc( sizeof(char*)*argc + n );
-  if( azArg==0 ){
-    return SQLITE_NOMEM;
+
+  for(i=0; i<MERGE_COUNT; i++){
+    leavesReaderDestroy(&lrs[i]);
   }
-  z = (char*)&azArg[argc];
-  for(i=0; i<argc; i++){
-    azArg[i] = z;
-    strcpy(z, argv[i]);
-    z += strlen(z)+1;
+
+  rc = leafWriterFinalize(v, &writer);
+  leafWriterDestroy(&writer);
+  if( rc!=SQLITE_OK ) return rc;
+
+  /* Delete the merged segment data. */
+  return segdir_delete(v, iLevel);
+
+ err:
+  for(i=0; i<MERGE_COUNT; i++){
+    leavesReaderDestroy(&lrs[i]);
   }
+  leafWriterDestroy(&writer);
+  return rc;
+}
 
-  /* Identify the column names and the tokenizer and delimiter arguments
-  ** in the argv[][] array.
+/* Accumulate the union of *acc and *pData into *acc. */
+static void docListAccumulateUnion(DataBuffer *acc,
+                                   const char *pData, int nData) {
+  DataBuffer tmp = *acc;
+  dataBufferInit(acc, tmp.nData+nData);
+  docListUnion(tmp.pData, tmp.nData, pData, nData, acc);
+  dataBufferDestroy(&tmp);
+}
+
+/* TODO(shess) It might be interesting to explore different merge
+** strategies, here.  For instance, since this is a sorted merge, we
+** could easily merge many doclists in parallel.  With some
+** comprehension of the storage format, we could merge all of the
+** doclists within a leaf node directly from the leaf node's storage.
+** It may be worthwhile to merge smaller doclists before larger
+** doclists, since they can be traversed more quickly - but the
+** results may have less overlap, making them more expensive in a
+** different way.
+*/
+
+/* Scan pReader for pTerm/nTerm, and merge the term's doclist over
+** *out (any doclists with duplicate docids overwrite those in *out).
+** Internal function for loadSegmentLeaf().
+*/
+static int loadSegmentLeavesInt(fulltext_vtab *v, LeavesReader *pReader,
+                                const char *pTerm, int nTerm, int isPrefix,
+                                DataBuffer *out){
+  /* doclist data is accumulated into pBuffers similar to how one does
+  ** increment in binary arithmetic.  If index 0 is empty, the data is
+  ** stored there.  If there is data there, it is merged and the
+  ** results carried into position 1, with further merge-and-carry
+  ** until an empty position is found.
   */
-  pSpec->zDb = azArg[1];
-  pSpec->zName = azArg[2];
-  pSpec->nColumn = 0;
-  pSpec->azColumn = azArg;
-  zTokenizer = "tokenize simple";
-  for(i=3; i<argc; ++i){
-    if( startsWith(azArg[i],"tokenize") ){
-      zTokenizer = azArg[i];
-    }else{
-      z = azArg[pSpec->nColumn] = firstToken(azArg[i], &zDummy);
-      pSpec->nColumn++;
+  DataBuffer *pBuffers = NULL;
+  int nBuffers = 0, nMaxBuffers = 0, rc;
+
+  assert( nTerm>0 );
+
+  for(rc=SQLITE_OK; rc==SQLITE_OK && !leavesReaderAtEnd(pReader);
+      rc=leavesReaderStep(v, pReader)){
+    /* TODO(shess) Really want leavesReaderTermCmp(), but that name is
+    ** already taken to compare the terms of two LeavesReaders.  Think
+    ** on a better name.  [Meanwhile, break encapsulation rather than
+    ** use a confusing name.]
+    */
+    int c = leafReaderTermCmp(&pReader->leafReader, pTerm, nTerm, isPrefix);
+    if( c>0 ) break;      /* Past any possible matches. */
+    if( c==0 ){
+      const char *pData = leavesReaderData(pReader);
+      int iBuffer, nData = leavesReaderDataBytes(pReader);
+
+      /* Find the first empty buffer. */
+      for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
+        if( 0==pBuffers[iBuffer].nData ) break;
+      }
+
+      /* Out of buffers, add an empty one. */
+      if( iBuffer==nBuffers ){
+        if( nBuffers==nMaxBuffers ){
+          DataBuffer *p;
+          nMaxBuffers += 20;
+
+          /* Manual realloc so we can handle NULL appropriately. */
+          p = sqlite3_malloc(nMaxBuffers*sizeof(*pBuffers));
+          if( p==NULL ){
+            rc = SQLITE_NOMEM;
+            break;
+          }
+
+          if( nBuffers>0 ){
+            assert(pBuffers!=NULL);
+            memcpy(p, pBuffers, nBuffers*sizeof(*pBuffers));
+            sqlite3_free(pBuffers);
+          }
+          pBuffers = p;
+        }
+        dataBufferInit(&(pBuffers[nBuffers]), 0);
+        nBuffers++;
+      }
+
+      /* At this point, must have an empty at iBuffer. */
+      assert(iBuffer<nBuffers && pBuffers[iBuffer].nData==0);
+
+      /* If empty was first buffer, no need for merge logic. */
+      if( iBuffer==0 ){
+        dataBufferReplace(&(pBuffers[0]), pData, nData);
+      }else{
+        /* pAcc is the empty buffer the merged data will end up in. */
+        DataBuffer *pAcc = &(pBuffers[iBuffer]);
+        DataBuffer *p = &(pBuffers[0]);
+
+        /* Handle position 0 specially to avoid need to prime pAcc
+        ** with pData/nData.
+        */
+        dataBufferSwap(p, pAcc);
+        docListAccumulateUnion(pAcc, pData, nData);
+
+        /* Accumulate remaining doclists into pAcc. */
+        for(++p; p<pAcc; ++p){
+          docListAccumulateUnion(pAcc, p->pData, p->nData);
+
+          /* dataBufferReset() could allow a large doclist to blow up
+          ** our memory requirements.
+          */
+          if( p->nCapacity<1024 ){
+            dataBufferReset(p);
+          }else{
+            dataBufferDestroy(p);
+            dataBufferInit(p, 0);
+          }
+        }
+      }
     }
   }
-  if( pSpec->nColumn==0 ){
-    azArg[0] = "content";
-    pSpec->nColumn = 1;
-  }
 
-  /*
-  ** Construct the list of content column names.
-  **
-  ** Each content column name will be of the form cNNAAAA
-  ** where NN is the column number and AAAA is the sanitized
-  ** column name.  "sanitized" means that special characters are
-  ** converted to "_".  The cNN prefix guarantees that all column
-  ** names are unique.
-  **
-  ** The AAAA suffix is not strictly necessary.  It is included
-  ** for the convenience of people who might examine the generated
-  ** %_content table and wonder what the columns are used for.
-  */
-  pSpec->azContentColumn = sqlite3_malloc( pSpec->nColumn * sizeof(char *) );
-  if( pSpec->azContentColumn==0 ){
-    clearTableSpec(pSpec);
-    return SQLITE_NOMEM;
-  }
-  for(i=0; i<pSpec->nColumn; i++){
-    char *p;
-    pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]);
-    for (p = pSpec->azContentColumn[i]; *p ; ++p) {
-      if( !safe_isalnum(*p) ) *p = '_';
+  /* Union all the doclists together into *out. */
+  /* TODO(shess) What if *out is big?  Sigh. */
+  if( rc==SQLITE_OK && nBuffers>0 ){
+    int iBuffer;
+    for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
+      if( pBuffers[iBuffer].nData>0 ){
+        if( out->nData==0 ){
+          dataBufferSwap(out, &(pBuffers[iBuffer]));
+        }else{
+          docListAccumulateUnion(out, pBuffers[iBuffer].pData,
+                                 pBuffers[iBuffer].nData);
+        }
+      }
     }
   }
 
-  /*
-  ** Parse the tokenizer specification string.
-  */
-  pSpec->azTokenizer = tokenizeString(zTokenizer, &n);
-  tokenListToIdList(pSpec->azTokenizer);
+  while( nBuffers-- ){
+    dataBufferDestroy(&(pBuffers[nBuffers]));
+  }
+  if( pBuffers!=NULL ) sqlite3_free(pBuffers);
 
-  return SQLITE_OK;
+  return rc;
 }
 
-/*
-** Generate a CREATE TABLE statement that describes the schema of
-** the virtual table.  Return a pointer to this schema string.
-**
-** Space is obtained from sqlite3_mprintf() and should be freed
-** using sqlite3_free().
-*/
-static char *fulltextSchema(
-  int nColumn,                  /* Number of columns */
-  const char *const* azColumn,  /* List of columns */
-  const char *zTableName        /* Name of the table */
-){
-  int i;
-  char *zSchema, *zNext;
-  const char *zSep = "(";
-  zSchema = sqlite3_mprintf("CREATE TABLE x");
-  for(i=0; i<nColumn; i++){
-    zNext = sqlite3_mprintf("%s%s%Q", zSchema, zSep, azColumn[i]);
-    sqlite3_free(zSchema);
-    zSchema = zNext;
-    zSep = ",";
-  }
-  zNext = sqlite3_mprintf("%s,%Q HIDDEN", zSchema, zTableName);
-  sqlite3_free(zSchema);
-  zSchema = zNext;
-  zNext = sqlite3_mprintf("%s,docid HIDDEN)", zSchema);
-  sqlite3_free(zSchema);
-  return zNext;
+/* Call loadSegmentLeavesInt() with pData/nData as input. */
+static int loadSegmentLeaf(fulltext_vtab *v, const char *pData, int nData,
+                           const char *pTerm, int nTerm, int isPrefix,
+                           DataBuffer *out){
+  LeavesReader reader;
+  int rc;
+
+  assert( nData>1 );
+  assert( *pData=='\0' );
+  rc = leavesReaderInit(v, 0, 0, 0, pData, nData, &reader);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
+  leavesReaderReset(&reader);
+  leavesReaderDestroy(&reader);
+  return rc;
 }
 
-/*
-** Build a new sqlite3_vtab structure that will describe the
-** fulltext index defined by spec.
+/* Call loadSegmentLeavesInt() with the leaf nodes from iStartLeaf to
+** iEndLeaf (inclusive) as input, and merge the resulting doclist into
+** out.
 */
-static int constructVtab(
-  sqlite3 *db,              /* The SQLite database connection */
-  fts3Hash *pHash,          /* Hash table containing tokenizers */
-  TableSpec *spec,          /* Parsed spec information from parseSpec() */
-  sqlite3_vtab **ppVTab,    /* Write the resulting vtab structure here */
-  char **pzErr              /* Write any error message here */
-){
+static int loadSegmentLeaves(fulltext_vtab *v,
+                             sqlite_int64 iStartLeaf, sqlite_int64 iEndLeaf,
+                             const char *pTerm, int nTerm, int isPrefix,
+                             DataBuffer *out){
   int rc;
-  int n;
-  fulltext_vtab *v = 0;
-  const sqlite3_tokenizer_module *m = NULL;
-  char *schema;
+  LeavesReader reader;
 
-  char const *zTok;         /* Name of tokenizer to use for this fts table */
-  int nTok;                 /* Length of zTok, including nul terminator */
+  assert( iStartLeaf<=iEndLeaf );
+  rc = leavesReaderInit(v, 0, iStartLeaf, iEndLeaf, NULL, 0, &reader);
+  if( rc!=SQLITE_OK ) return rc;
 
-  v = (fulltext_vtab *) sqlite3_malloc(sizeof(fulltext_vtab));
-  if( v==0 ) return SQLITE_NOMEM;
-  CLEAR(v);
-  /* sqlite will initialize v->base */
-  v->db = db;
-  v->zDb = spec->zDb;       /* Freed when azColumn is freed */
-  v->zName = spec->zName;   /* Freed when azColumn is freed */
-  v->nColumn = spec->nColumn;
-  v->azContentColumn = spec->azContentColumn;
-  spec->azContentColumn = 0;
-  v->azColumn = spec->azColumn;
-  spec->azColumn = 0;
+  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
+  leavesReaderReset(&reader);
+  leavesReaderDestroy(&reader);
+  return rc;
+}
+
+/* Taking pData/nData as an interior node, find the sequence of child
+** nodes which could include pTerm/nTerm/isPrefix.  Note that the
+** interior node terms logically come between the blocks, so there is
+** one more blockid than there are terms (that block contains terms >=
+** the last interior-node term).
+*/
+/* TODO(shess) The calling code may already know that the end child is
+** not worth calculating, because the end may be in a later sibling
+** node.  Consider whether breaking symmetry is worthwhile.  I suspect
+** it is not worthwhile.
+*/
+static void getChildrenContaining(const char *pData, int nData,
+                                  const char *pTerm, int nTerm, int isPrefix,
+                                  sqlite_int64 *piStartChild,
+                                  sqlite_int64 *piEndChild){
+  InteriorReader reader;
 
-  if( spec->azTokenizer==0 ){
-    return SQLITE_NOMEM;
-  }
+  assert( nData>1 );
+  assert( *pData!='\0' );
+  interiorReaderInit(pData, nData, &reader);
 
-  zTok = spec->azTokenizer[0]; 
-  if( !zTok ){
-    zTok = "simple";
+  /* Scan for the first child which could contain pTerm/nTerm. */
+  while( !interiorReaderAtEnd(&reader) ){
+    if( interiorReaderTermCmp(&reader, pTerm, nTerm, 0)>0 ) break;
+    interiorReaderStep(&reader);
   }
-  nTok = strlen(zTok)+1;
+  *piStartChild = interiorReaderCurrentBlockid(&reader);
 
-  m = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zTok, nTok);
-  if( !m ){
-    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", spec->azTokenizer[0]);
-    rc = SQLITE_ERROR;
-    goto err;
+  /* Keep scanning to find a term greater than our term, using prefix
+  ** comparison if indicated.  If isPrefix is false, this will be the
+  ** same blockid as the starting block.
+  */
+  while( !interiorReaderAtEnd(&reader) ){
+    if( interiorReaderTermCmp(&reader, pTerm, nTerm, isPrefix)>0 ) break;
+    interiorReaderStep(&reader);
   }
+  *piEndChild = interiorReaderCurrentBlockid(&reader);
 
-  for(n=0; spec->azTokenizer[n]; n++){}
-  if( n ){
-    rc = m->xCreate(n-1, (const char*const*)&spec->azTokenizer[1],
-                    &v->pTokenizer);
-  }else{
-    rc = m->xCreate(0, 0, &v->pTokenizer);
-  }
-  if( rc!=SQLITE_OK ) goto err;
-  v->pTokenizer->pModule = m;
+  interiorReaderDestroy(&reader);
 
-  /* TODO: verify the existence of backing tables foo_content, foo_term */
+  /* Children must ascend, and if !prefix, both must be the same. */
+  assert( *piEndChild>=*piStartChild );
+  assert( isPrefix || *piStartChild==*piEndChild );
+}
 
-  schema = fulltextSchema(v->nColumn, (const char*const*)v->azColumn,
-                          spec->zName);
-  rc = sqlite3_declare_vtab(db, schema);
-  sqlite3_free(schema);
-  if( rc!=SQLITE_OK ) goto err;
+/* Read block at iBlockid and pass it with other params to
+** getChildrenContaining().
+*/
+static int loadAndGetChildrenContaining(
+  fulltext_vtab *v,
+  sqlite_int64 iBlockid,
+  const char *pTerm, int nTerm, int isPrefix,
+  sqlite_int64 *piStartChild, sqlite_int64 *piEndChild
+){
+  sqlite3_stmt *s = NULL;
+  int rc;
 
-  memset(v->pFulltextStatements, 0, sizeof(v->pFulltextStatements));
+  assert( iBlockid!=0 );
+  assert( pTerm!=NULL );
+  assert( nTerm!=0 );        /* TODO(shess) Why not allow this? */
+  assert( piStartChild!=NULL );
+  assert( piEndChild!=NULL );
 
-  /* Indicate that the buffer is not live. */
-  v->nPendingData = -1;
+  rc = sql_get_statement(v, BLOCK_SELECT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-  *ppVTab = &v->base;
-  FTSTRACE(("FTS3 Connect %p\n", v));
+  rc = sqlite3_bind_int64(s, 1, iBlockid);
+  if( rc!=SQLITE_OK ) return rc;
 
-  return rc;
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_ERROR;
+  if( rc!=SQLITE_ROW ) return rc;
 
-err:
-  fulltext_vtab_destroy(v);
-  return rc;
+  getChildrenContaining(sqlite3_column_blob(s, 0), sqlite3_column_bytes(s, 0),
+                        pTerm, nTerm, isPrefix, piStartChild, piEndChild);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain
+   * locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+
+  return SQLITE_OK;
 }
 
-static int fulltextConnect(
-  sqlite3 *db,
-  void *pAux,
-  int argc, const char *const*argv,
-  sqlite3_vtab **ppVTab,
-  char **pzErr
-){
-  TableSpec spec;
-  int rc = parseSpec(&spec, argc, argv, pzErr);
-  if( rc!=SQLITE_OK ) return rc;
+/* Traverse the tree represented by pData[nData] looking for
+** pTerm[nTerm], placing its doclist into *out.  This is internal to
+** loadSegment() to make error-handling cleaner.
+*/
+static int loadSegmentInt(fulltext_vtab *v, const char *pData, int nData,
+                          sqlite_int64 iLeavesEnd,
+                          const char *pTerm, int nTerm, int isPrefix,
+                          DataBuffer *out){
+  /* Special case where root is a leaf. */
+  if( *pData=='\0' ){
+    return loadSegmentLeaf(v, pData, nData, pTerm, nTerm, isPrefix, out);
+  }else{
+    int rc;
+    sqlite_int64 iStartChild, iEndChild;
 
-  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
-  clearTableSpec(&spec);
-  return rc;
+    /* Process pData as an interior node, then loop down the tree
+    ** until we find the set of leaf nodes to scan for the term.
+    */
+    getChildrenContaining(pData, nData, pTerm, nTerm, isPrefix,
+                          &iStartChild, &iEndChild);
+    while( iStartChild>iLeavesEnd ){
+      sqlite_int64 iNextStart, iNextEnd;
+      rc = loadAndGetChildrenContaining(v, iStartChild, pTerm, nTerm, isPrefix,
+                                        &iNextStart, &iNextEnd);
+      if( rc!=SQLITE_OK ) return rc;
+
+      /* If we've branched, follow the end branch, too. */
+      if( iStartChild!=iEndChild ){
+        sqlite_int64 iDummy;
+        rc = loadAndGetChildrenContaining(v, iEndChild, pTerm, nTerm, isPrefix,
+                                          &iDummy, &iNextEnd);
+        if( rc!=SQLITE_OK ) return rc;
+      }
+
+      assert( iNextStart<=iNextEnd );
+      iStartChild = iNextStart;
+      iEndChild = iNextEnd;
+    }
+    assert( iStartChild<=iLeavesEnd );
+    assert( iEndChild<=iLeavesEnd );
+
+    /* Scan through the leaf segments for doclists. */
+    return loadSegmentLeaves(v, iStartChild, iEndChild,
+                             pTerm, nTerm, isPrefix, out);
+  }
 }
 
-/* The %_content table holds the text of each document, with
-** the docid column exposed as the SQLite rowid for the table.
+/* Call loadSegmentInt() to collect the doclist for pTerm/nTerm, then
+** merge its doclist over *out (any duplicate doclists read from the
+** segment rooted at pData will overwrite those in *out).
 */
-/* TODO(shess) This comment needs elaboration to match the updated
-** code.  Work it into the top-of-file comment at that time.
+/* TODO(shess) Consider changing this to determine the depth of the
+** leaves using either the first characters of interior nodes (when
+** ==1, we're one level above the leaves), or the first character of
+** the root (which will describe the height of the tree directly).
+** Either feels somewhat tricky to me.
 */
-static int fulltextCreate(sqlite3 *db, void *pAux,
-                          int argc, const char * const *argv,
-                          sqlite3_vtab **ppVTab, char **pzErr){
+/* TODO(shess) The current merge is likely to be slow for large
+** doclists (though it should process from newest/smallest to
+** oldest/largest, so it may not be that bad).  It might be useful to
+** modify things to allow for N-way merging.  This could either be
+** within a segment, with pairwise merges across segments, or across
+** all segments at once.
+*/
+static int loadSegment(fulltext_vtab *v, const char *pData, int nData,
+                       sqlite_int64 iLeavesEnd,
+                       const char *pTerm, int nTerm, int isPrefix,
+                       DataBuffer *out){
+  DataBuffer result;
   int rc;
-  TableSpec spec;
-  StringBuffer schema;
-  FTSTRACE(("FTS3 Create\n"));
-
-  rc = parseSpec(&spec, argc, argv, pzErr);
-  if( rc!=SQLITE_OK ) return rc;
-
-  initStringBuffer(&schema);
-  append(&schema, "CREATE TABLE %_content(");
-  append(&schema, "  docid INTEGER PRIMARY KEY,");
-  appendList(&schema, spec.nColumn, spec.azContentColumn);
-  append(&schema, ")");
-  rc = sql_exec(db, spec.zDb, spec.zName, stringBufferData(&schema));
-  stringBufferDestroy(&schema);
-  if( rc!=SQLITE_OK ) goto out;
 
-  rc = sql_exec(db, spec.zDb, spec.zName,
-                "create table %_segments("
-                "  blockid INTEGER PRIMARY KEY,"
-                "  block blob"
-                ");"
-                );
-  if( rc!=SQLITE_OK ) goto out;
+  assert( nData>1 );
 
-  rc = sql_exec(db, spec.zDb, spec.zName,
-                "create table %_segdir("
-                "  level integer,"
-                "  idx integer,"
-                "  start_block integer,"
-                "  leaves_end_block integer,"
-                "  end_block integer,"
-                "  root blob,"
-                "  primary key(level, idx)"
-                ");");
-  if( rc!=SQLITE_OK ) goto out;
+  /* This code should never be called with buffered updates. */
+  assert( v->nPendingData<0 );
 
-  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
+  dataBufferInit(&result, 0);
+  rc = loadSegmentInt(v, pData, nData, iLeavesEnd,
+                      pTerm, nTerm, isPrefix, &result);
+  if( rc==SQLITE_OK && result.nData>0 ){
+    if( out->nData==0 ){
+      DataBuffer tmp = *out;
+      *out = result;
+      result = tmp;
+    }else{
+      DataBuffer merged;
+      DLReader readers[2];
 
-out:
-  clearTableSpec(&spec);
+      dlrInit(&readers[0], DL_DEFAULT, out->pData, out->nData);
+      dlrInit(&readers[1], DL_DEFAULT, result.pData, result.nData);
+      dataBufferInit(&merged, out->nData+result.nData);
+      docListMerge(&merged, readers, 2);
+      dataBufferDestroy(out);
+      *out = merged;
+      dlrDestroy(&readers[0]);
+      dlrDestroy(&readers[1]);
+    }
+  }
+  dataBufferDestroy(&result);
   return rc;
 }
 
-/* Decide how to handle an SQL query. */
-static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
-  fulltext_vtab *v = (fulltext_vtab *)pVTab;
-  int i;
-  FTSTRACE(("FTS3 BestIndex\n"));
-
-  for(i=0; i<pInfo->nConstraint; ++i){
-    const struct sqlite3_index_constraint *pConstraint;
-    pConstraint = &pInfo->aConstraint[i];
-    if( pConstraint->usable ) {
-      if( (pConstraint->iColumn==-1 || pConstraint->iColumn==v->nColumn+1) &&
-          pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
-        pInfo->idxNum = QUERY_DOCID;      /* lookup by docid */
-        FTSTRACE(("FTS3 QUERY_DOCID\n"));
-      } else if( pConstraint->iColumn>=0 && pConstraint->iColumn<=v->nColumn &&
-                 pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
-        /* full-text search */
-        pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn;
-        FTSTRACE(("FTS3 QUERY_FULLTEXT %d\n", pConstraint->iColumn));
-      } else continue;
+/* Scan the database and merge together the posting lists for the term
+** into *out.
+*/
+static int termSelect(
+  fulltext_vtab *v, 
+  int iColumn,
+  const char *pTerm, int nTerm,             /* Term to query for */
+  int isPrefix,                             /* True for a prefix search */
+  DocListType iType, 
+  DataBuffer *out                           /* Write results here */
+){
+  DataBuffer doclist;
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-      pInfo->aConstraintUsage[i].argvIndex = 1;
-      pInfo->aConstraintUsage[i].omit = 1;
+  /* This code should never be called with buffered updates. */
+  assert( v->nPendingData<0 );
 
-      /* An arbitrary value for now.
-       * TODO: Perhaps docid matches should be considered cheaper than
-       * full-text searches. */
-      pInfo->estimatedCost = 1.0;   
+  dataBufferInit(&doclist, 0);
+  dataBufferInit(out, 0);
 
-      return SQLITE_OK;
+  /* Traverse the segments from oldest to newest so that newer doclist
+  ** elements for given docids overwrite older elements.
+  */
+  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+    const char *pData = sqlite3_column_blob(s, 2);
+    const int nData = sqlite3_column_bytes(s, 2);
+    const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
+    rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, isPrefix,
+                     &doclist);
+    if( rc!=SQLITE_OK ) goto err;
+  }
+  if( rc==SQLITE_DONE ){
+    if( doclist.nData!=0 ){
+      /* TODO(shess) The old term_select_all() code applied the column
+      ** restrict as we merged segments, leading to smaller buffers.
+      ** This is probably worthwhile to bring back, once the new storage
+      ** system is checked in.
+      */
+      if( iColumn==v->nColumn) iColumn = -1;
+      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
+                  iColumn, iType, out);
     }
+    rc = SQLITE_OK;
   }
-  pInfo->idxNum = QUERY_GENERIC;
-  return SQLITE_OK;
+
+ err:
+  dataBufferDestroy(&doclist);
+  return rc;
 }
 
-static int fulltextDisconnect(sqlite3_vtab *pVTab){
-  FTSTRACE(("FTS3 Disconnect %p\n", pVTab));
-  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
-  return SQLITE_OK;
+/****************************************************************/
+/* Used to hold hashtable data for sorting. */
+typedef struct TermData {
+  const char *pTerm;
+  int nTerm;
+  DLCollector *pCollector;
+} TermData;
+
+/* Orders TermData elements in strcmp fashion ( <0 for less-than, 0
+** for equal, >0 for greater-than).
+*/
+static int termDataCmp(const void *av, const void *bv){
+  const TermData *a = (const TermData *)av;
+  const TermData *b = (const TermData *)bv;
+  int n = a->nTerm<b->nTerm ? a->nTerm : b->nTerm;
+  int c = memcmp(a->pTerm, b->pTerm, n);
+  if( c!=0 ) return c;
+  return a->nTerm-b->nTerm;
 }
 
-static int fulltextDestroy(sqlite3_vtab *pVTab){
-  fulltext_vtab *v = (fulltext_vtab *)pVTab;
-  int rc;
+/* Order pTerms data by term, then write a new level 0 segment using
+** LeafWriter.
+*/
+static int writeZeroSegment(fulltext_vtab *v, fts3Hash *pTerms){
+  fts3HashElem *e;
+  int idx, rc, i, n;
+  TermData *pData;
+  LeafWriter writer;
+  DataBuffer dl;
 
-  FTSTRACE(("FTS3 Destroy %p\n", pVTab));
-  rc = sql_exec(v->db, v->zDb, v->zName,
-                "drop table if exists %_content;"
-                "drop table if exists %_segments;"
-                "drop table if exists %_segdir;"
-                );
+  /* Determine the next index at level 0, merging as necessary. */
+  rc = segdirNextIndex(v, 0, &idx);
   if( rc!=SQLITE_OK ) return rc;
 
-  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
-  return SQLITE_OK;
-}
-
-static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
-  fulltext_cursor *c;
+  n = fts3HashCount(pTerms);
+  pData = sqlite3_malloc(n*sizeof(TermData));
 
-  c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
-  if( c ){
-    memset(c, 0, sizeof(fulltext_cursor));
-    /* sqlite will initialize c->base */
-    *ppCursor = &c->base;
-    FTSTRACE(("FTS3 Open %p: %p\n", pVTab, c));
-    return SQLITE_OK;
-  }else{
-    return SQLITE_NOMEM;
+  for(i = 0, e = fts3HashFirst(pTerms); e; i++, e = fts3HashNext(e)){
+    assert( i<n );
+    pData[i].pTerm = fts3HashKey(e);
+    pData[i].nTerm = fts3HashKeysize(e);
+    pData[i].pCollector = fts3HashData(e);
   }
-}
+  assert( i==n );
 
+  /* TODO(shess) Should we allow user-defined collation sequences,
+  ** here?  I think we only need that once we support prefix searches.
+  */
+  if( n>1 ) qsort(pData, n, sizeof(*pData), termDataCmp);
 
-/* Free all of the dynamically allocated memory held by *q
-*/
-static void queryClear(Query *q){
-  int i;
-  for(i = 0; i < q->nTerms; ++i){
-    sqlite3_free(q->pTerms[i].pTerm);
+  /* TODO(shess) Refactor so that we can write directly to the segment
+  ** DataBuffer, as happens for segment merges.
+  */
+  leafWriterInit(0, idx, &writer);
+  dataBufferInit(&dl, 0);
+  for(i=0; i<n; i++){
+    dataBufferReset(&dl);
+    dlcAddDoclist(pData[i].pCollector, &dl);
+    rc = leafWriterStep(v, &writer,
+                        pData[i].pTerm, pData[i].nTerm, dl.pData, dl.nData);
+    if( rc!=SQLITE_OK ) goto err;
   }
-  sqlite3_free(q->pTerms);
-  CLEAR(q);
-}
+  rc = leafWriterFinalize(v, &writer);
 
-/* Free all of the dynamically allocated memory held by the
-** Snippet
-*/
-static void snippetClear(Snippet *p){
-  sqlite3_free(p->aMatch);
-  sqlite3_free(p->zOffset);
-  sqlite3_free(p->zSnippet);
-  CLEAR(p);
+ err:
+  dataBufferDestroy(&dl);
+  sqlite3_free(pData);
+  leafWriterDestroy(&writer);
+  return rc;
 }
-/*
-** Append a single entry to the p->aMatch[] log.
-*/
-static void snippetAppendMatch(
-  Snippet *p,               /* Append the entry to this snippet */
-  int iCol, int iTerm,      /* The column and query term */
-  int iToken,               /* Matching token in document */
-  int iStart, int nByte     /* Offset and size of the match */
-){
-  int i;
-  struct snippetMatch *pMatch;
-  if( p->nMatch+1>=p->nAlloc ){
-    p->nAlloc = p->nAlloc*2 + 10;
-    p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
-    if( p->aMatch==0 ){
-      p->nMatch = 0;
-      p->nAlloc = 0;
-      return;
+
+/* If pendingTerms has data, free it. */
+static int clearPendingTerms(fulltext_vtab *v){
+  if( v->nPendingData>=0 ){
+    fts3HashElem *e;
+    for(e=fts3HashFirst(&v->pendingTerms); e; e=fts3HashNext(e)){
+      dlcDelete(fts3HashData(e));
     }
+    fts3HashClear(&v->pendingTerms);
+    v->nPendingData = -1;
   }
-  i = p->nMatch++;
-  pMatch = &p->aMatch[i];
-  pMatch->iCol = iCol;
-  pMatch->iTerm = iTerm;
-  pMatch->iToken = iToken;
-  pMatch->iStart = iStart;
-  pMatch->nByte = nByte;
+  return SQLITE_OK;
 }
 
-/*
-** Sizing information for the circular buffer used in snippetOffsetsOfColumn()
+/* If pendingTerms has data, flush it to a level-zero segment, and
+** free it.
 */
-#define FTS3_ROTOR_SZ   (32)
-#define FTS3_ROTOR_MASK (FTS3_ROTOR_SZ-1)
+static int flushPendingTerms(fulltext_vtab *v){
+  if( v->nPendingData>=0 ){
+    int rc = writeZeroSegment(v, &v->pendingTerms);
+    if( rc==SQLITE_OK ) clearPendingTerms(v);
+    return rc;
+  }
+  return SQLITE_OK;
+}
 
-/*
-** Add entries to pSnippet->aMatch[] for every match that occurs against
-** document zDoc[0..nDoc-1] which is stored in column iColumn.
+/* If pendingTerms is "too big", or docid is out of order, flush it.
+** Regardless, be certain that pendingTerms is initialized for use.
 */
-static void snippetOffsetsOfColumn(
-  Query *pQuery,
-  Snippet *pSnippet,
-  int iColumn,
-  const char *zDoc,
-  int nDoc
-){
-  const sqlite3_tokenizer_module *pTModule;  /* The tokenizer module */
-  sqlite3_tokenizer *pTokenizer;             /* The specific tokenizer */
-  sqlite3_tokenizer_cursor *pTCursor;        /* Tokenizer cursor */
-  fulltext_vtab *pVtab;                /* The full text index */
-  int nColumn;                         /* Number of columns in the index */
-  const QueryTerm *aTerm;              /* Query string terms */
-  int nTerm;                           /* Number of query string terms */  
-  int i, j;                            /* Loop counters */
-  int rc;                              /* Return code */
-  unsigned int match, prevMatch;       /* Phrase search bitmasks */
-  const char *zToken;                  /* Next token from the tokenizer */
-  int nToken;                          /* Size of zToken */
-  int iBegin, iEnd, iPos;              /* Offsets of beginning and end */
-
-  /* The following variables keep a circular buffer of the last
-  ** few tokens */
-  unsigned int iRotor = 0;             /* Index of current token */
-  int iRotorBegin[FTS3_ROTOR_SZ];      /* Beginning offset of token */
-  int iRotorLen[FTS3_ROTOR_SZ];        /* Length of token */
-
-  pVtab = pQuery->pFts;
-  nColumn = pVtab->nColumn;
-  pTokenizer = pVtab->pTokenizer;
-  pTModule = pTokenizer->pModule;
-  rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor);
-  if( rc ) return;
-  pTCursor->pTokenizer = pTokenizer;
-  aTerm = pQuery->pTerms;
-  nTerm = pQuery->nTerms;
-  if( nTerm>=FTS3_ROTOR_SZ ){
-    nTerm = FTS3_ROTOR_SZ - 1;
+static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid){
+  /* TODO(shess) Explore whether partially flushing the buffer on
+  ** forced-flush would provide better performance.  I suspect that if
+  ** we ordered the doclists by size and flushed the largest until the
+  ** buffer was half empty, that would let the less frequent terms
+  ** generate longer doclists.
+  */
+  if( iDocid<=v->iPrevDocid || v->nPendingData>kPendingThreshold ){
+    int rc = flushPendingTerms(v);
+    if( rc!=SQLITE_OK ) return rc;
   }
-  prevMatch = 0;
-  while(1){
-    rc = pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
-    if( rc ) break;
-    iRotorBegin[iRotor&FTS3_ROTOR_MASK] = iBegin;
-    iRotorLen[iRotor&FTS3_ROTOR_MASK] = iEnd-iBegin;
-    match = 0;
-    for(i=0; i<nTerm; i++){
-      int iCol;
-      iCol = aTerm[i].iColumn;
-      if( iCol>=0 && iCol<nColumn && iCol!=iColumn ) continue;
-      if( aTerm[i].nTerm>nToken ) continue;
-      if( !aTerm[i].isPrefix && aTerm[i].nTerm<nToken ) continue;
-      assert( aTerm[i].nTerm<=nToken );
-      if( memcmp(aTerm[i].pTerm, zToken, aTerm[i].nTerm) ) continue;
-      if( aTerm[i].iPhrase>1 && (prevMatch & (1<<i))==0 ) continue;
-      match |= 1<<i;
-      if( i==nTerm-1 || aTerm[i+1].iPhrase==1 ){
-        for(j=aTerm[i].iPhrase-1; j>=0; j--){
-          int k = (iRotor-j) & FTS3_ROTOR_MASK;
-          snippetAppendMatch(pSnippet, iColumn, i-j, iPos-j,
-                iRotorBegin[k], iRotorLen[k]);
-        }
-      }
-    }
-    prevMatch = match<<1;
-    iRotor++;
+  if( v->nPendingData<0 ){
+    fts3HashInit(&v->pendingTerms, FTS3_HASH_STRING, 1);
+    v->nPendingData = 0;
   }
-  pTModule->xClose(pTCursor);  
+  v->iPrevDocid = iDocid;
+  return SQLITE_OK;
 }
 
-/*
-** Remove entries from the pSnippet structure to account for the NEAR
-** operator. When this is called, pSnippet contains the list of token 
-** offsets produced by treating all NEAR operators as AND operators.
-** This function removes any entries that should not be present after
-** accounting for the NEAR restriction. For example, if the queried
-** document is:
-**
-**     "A B C D E A"
-**
-** and the query is:
-** 
-**     A NEAR/0 E
-**
-** then when this function is called the Snippet contains token offsets
-** 0, 4 and 5. This function removes the "0" entry (because the first A
-** is not near enough to an E).
-*/
-static void trimSnippetOffsetsForNear(Query *pQuery, Snippet *pSnippet){
-  int ii;
-  int iDir = 1;
-
-  while(iDir>-2) {
-    assert( iDir==1 || iDir==-1 );
-    for(ii=0; ii<pSnippet->nMatch; ii++){
-      int jj;
-      int nNear;
-      struct snippetMatch *pMatch = &pSnippet->aMatch[ii];
-      QueryTerm *pQueryTerm = &pQuery->pTerms[pMatch->iTerm];
+/* This function implements the xUpdate callback; it is the top-level entry
+ * point for inserting, deleting or updating a row in a full-text table. */
+static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg,
+                          sqlite_int64 *pRowid){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+  int rc;
 
-      if( (pMatch->iTerm+iDir)<0 
-       || (pMatch->iTerm+iDir)>=pQuery->nTerms
-      ){
-        continue;
-      }
-     
-      nNear = pQueryTerm->nNear;
-      if( iDir<0 ){
-        nNear = pQueryTerm[-1].nNear;
-      }
-  
-      if( pMatch->iTerm>=0 && nNear ){
-        int isOk = 0;
-        int iNextTerm = pMatch->iTerm+iDir;
-        int iPrevTerm = iNextTerm;
-
-        int iEndToken;
-        int iStartToken;
-
-        if( iDir<0 ){
-          int nPhrase = 1;
-          iStartToken = pMatch->iToken;
-          while( (pMatch->iTerm+nPhrase)<pQuery->nTerms 
-              && pQuery->pTerms[pMatch->iTerm+nPhrase].iPhrase>1 
-          ){
-            nPhrase++;
-          }
-          iEndToken = iStartToken + nPhrase - 1;
-        }else{
-          iEndToken   = pMatch->iToken;
-          iStartToken = pMatch->iToken+1-pQueryTerm->iPhrase;
-        }
+  FTSTRACE(("FTS3 Update %p\n", pVtab));
 
-        while( pQuery->pTerms[iNextTerm].iPhrase>1 ){
-          iNextTerm--;
-        }
-        while( (iPrevTerm+1)<pQuery->nTerms && 
-               pQuery->pTerms[iPrevTerm+1].iPhrase>1 
-        ){
-          iPrevTerm++;
-        }
-  
-        for(jj=0; isOk==0 && jj<pSnippet->nMatch; jj++){
-          struct snippetMatch *p = &pSnippet->aMatch[jj];
-          if( p->iCol==pMatch->iCol && ((
-               p->iTerm==iNextTerm && 
-               p->iToken>iEndToken && 
-               p->iToken<=iEndToken+nNear
-          ) || (
-               p->iTerm==iPrevTerm && 
-               p->iToken<iStartToken && 
-               p->iToken>=iStartToken-nNear
-          ))){
-            isOk = 1;
-          }
-        }
-        if( !isOk ){
-          for(jj=1-pQueryTerm->iPhrase; jj<=0; jj++){
-            pMatch[jj].iTerm = -1;
-          }
-          ii = -1;
-          iDir = 1;
+  if( nArg<2 ){
+    rc = index_delete(v, sqlite3_value_int64(ppArg[0]));
+    if( rc==SQLITE_OK ){
+      /* If we just deleted the last row in the table, clear out the
+      ** index data.
+      */
+      rc = content_exists(v);
+      if( rc==SQLITE_ROW ){
+        rc = SQLITE_OK;
+      }else if( rc==SQLITE_DONE ){
+        /* Clear the pending terms so we don't flush a useless level-0
+        ** segment when the transaction closes.
+        */
+        rc = clearPendingTerms(v);
+        if( rc==SQLITE_OK ){
+          rc = segdir_delete_all(v);
         }
       }
     }
-    iDir -= 2;
+  } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){
+    /* An update:
+     * ppArg[0] = old rowid
+     * ppArg[1] = new rowid
+     * ppArg[2..2+v->nColumn-1] = values
+     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
+     * ppArg[2+v->nColumn+1] = value for docid
+     */
+    sqlite_int64 rowid = sqlite3_value_int64(ppArg[0]);
+    if( sqlite3_value_type(ppArg[1]) != SQLITE_INTEGER ||
+        sqlite3_value_int64(ppArg[1]) != rowid ){
+      rc = SQLITE_ERROR;  /* we don't allow changing the rowid */
+    }else if( sqlite3_value_type(ppArg[2+v->nColumn+1]) != SQLITE_INTEGER ||
+              sqlite3_value_int64(ppArg[2+v->nColumn+1]) != rowid ){
+      rc = SQLITE_ERROR;  /* we don't allow changing the docid */
+    }else{
+      assert( nArg==2+v->nColumn+2);
+      rc = index_update(v, rowid, &ppArg[2]);
+    }
+  } else {
+    /* An insert:
+     * ppArg[1] = requested rowid
+     * ppArg[2..2+v->nColumn-1] = values
+     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
+     * ppArg[2+v->nColumn+1] = value for docid
+     */
+    sqlite3_value *pRequestDocid = ppArg[2+v->nColumn+1];
+    assert( nArg==2+v->nColumn+2);
+    if( SQLITE_NULL != sqlite3_value_type(pRequestDocid) &&
+        SQLITE_NULL != sqlite3_value_type(ppArg[1]) ){
+      /* TODO(shess) Consider allowing this to work if the values are
+      ** identical.  I'm inclined to discourage that usage, though,
+      ** given that both rowid and docid are special columns.  Better
+      ** would be to define one or the other as the default winner,
+      ** but should it be fts3-centric (docid) or SQLite-centric
+      ** (rowid)?
+      */
+      rc = SQLITE_ERROR;
+    }else{
+      if( SQLITE_NULL == sqlite3_value_type(pRequestDocid) ){
+        pRequestDocid = ppArg[1];
+      }
+      rc = index_insert(v, pRequestDocid, &ppArg[2], pRowid);
+    }
   }
+
+  return rc;
 }
 
-/*
-** Compute all offsets for the current row of the query.  
-** If the offsets have already been computed, this routine is a no-op.
-*/
-static void snippetAllOffsets(fulltext_cursor *p){
-  int nColumn;
-  int iColumn, i;
-  int iFirst, iLast;
-  fulltext_vtab *pFts;
+static int fulltextSync(sqlite3_vtab *pVtab){
+  FTSTRACE(("FTS3 xSync()\n"));
+  return flushPendingTerms((fulltext_vtab *)pVtab);
+}
 
-  if( p->snippet.nMatch ) return;
-  if( p->q.nTerms==0 ) return;
-  pFts = p->q.pFts;
-  nColumn = pFts->nColumn;
-  iColumn = (p->iCursorType - QUERY_FULLTEXT);
-  if( iColumn<0 || iColumn>=nColumn ){
-    iFirst = 0;
-    iLast = nColumn-1;
-  }else{
-    iFirst = iColumn;
-    iLast = iColumn;
-  }
-  for(i=iFirst; i<=iLast; i++){
-    const char *zDoc;
-    int nDoc;
-    zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1);
-    nDoc = sqlite3_column_bytes(p->pStmt, i+1);
-    snippetOffsetsOfColumn(&p->q, &p->snippet, i, zDoc, nDoc);
-  }
+static int fulltextBegin(sqlite3_vtab *pVtab){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+  FTSTRACE(("FTS3 xBegin()\n"));
+
+  /* Any buffered updates should have been cleared by the previous
+  ** transaction.
+  */
+  assert( v->nPendingData<0 );
+  return clearPendingTerms(v);
+}
+
+static int fulltextCommit(sqlite3_vtab *pVtab){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+  FTSTRACE(("FTS3 xCommit()\n"));
 
-  trimSnippetOffsetsForNear(&p->q, &p->snippet);
+  /* Buffered updates should have been cleared by fulltextSync(). */
+  assert( v->nPendingData<0 );
+  return clearPendingTerms(v);
+}
+
+static int fulltextRollback(sqlite3_vtab *pVtab){
+  FTSTRACE(("FTS3 xRollback()\n"));
+  return clearPendingTerms((fulltext_vtab *)pVtab);
 }
 
 /*
-** Convert the information in the aMatch[] array of the snippet
-** into the string zOffset[0..nOffset-1].
+** Implementation of the snippet() function for FTS3
 */
-static void snippetOffsetText(Snippet *p){
-  int i;
-  int cnt = 0;
-  StringBuffer sb;
-  char zBuf[200];
-  if( p->zOffset ) return;
-  initStringBuffer(&sb);
-  for(i=0; i<p->nMatch; i++){
-    struct snippetMatch *pMatch = &p->aMatch[i];
-    if( pMatch->iTerm>=0 ){
-      /* If snippetMatch.iTerm is less than 0, then the match was 
-      ** discarded as part of processing the NEAR operator (see the 
-      ** trimSnippetOffsetsForNear() function for details). Ignore 
-      ** it in this case
-      */
-      zBuf[0] = ' ';
-      sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d",
-          pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte);
-      append(&sb, zBuf);
-      cnt++;
+static void snippetFunc(
+  sqlite3_context *pContext,
+  int argc,
+  sqlite3_value **argv
+){
+  fulltext_cursor *pCursor;
+  if( argc<1 ) return;
+  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1);
+  }else{
+    const char *zStart = "<b>";
+    const char *zEnd = "</b>";
+    const char *zEllipsis = "<b>...</b>";
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    if( argc>=2 ){
+      zStart = (const char*)sqlite3_value_text(argv[1]);
+      if( argc>=3 ){
+        zEnd = (const char*)sqlite3_value_text(argv[2]);
+        if( argc>=4 ){
+          zEllipsis = (const char*)sqlite3_value_text(argv[3]);
+        }
+      }
     }
+    snippetAllOffsets(pCursor);
+    snippetText(pCursor, zStart, zEnd, zEllipsis);
+    sqlite3_result_text(pContext, pCursor->snippet.zSnippet,
+                        pCursor->snippet.nSnippet, SQLITE_STATIC);
   }
-  p->zOffset = stringBufferData(&sb);
-  p->nOffset = stringBufferLength(&sb);
 }
 
 /*
-** zDoc[0..nDoc-1] is phrase of text.  aMatch[0..nMatch-1] are a set
-** of matching words some of which might be in zDoc.  zDoc is column
-** number iCol.
-**
-** iBreak is suggested spot in zDoc where we could begin or end an
-** excerpt.  Return a value similar to iBreak but possibly adjusted
-** to be a little left or right so that the break point is better.
+** Implementation of the offsets() function for FTS3
 */
-static int wordBoundary(
-  int iBreak,                   /* The suggested break point */
-  const char *zDoc,             /* Document text */
-  int nDoc,                     /* Number of bytes in zDoc[] */
-  struct snippetMatch *aMatch,  /* Matching words */
-  int nMatch,                   /* Number of entries in aMatch[] */
-  int iCol                      /* The column number for zDoc[] */
+static void snippetOffsetsFunc(
+  sqlite3_context *pContext,
+  int argc,
+  sqlite3_value **argv
 ){
-  int i;
-  if( iBreak<=10 ){
-    return 0;
-  }
-  if( iBreak>=nDoc-10 ){
-    return nDoc;
-  }
-  for(i=0; i<nMatch && aMatch[i].iCol<iCol; i++){}
-  while( i<nMatch && aMatch[i].iStart+aMatch[i].nByte<iBreak ){ i++; }
-  if( i<nMatch ){
-    if( aMatch[i].iStart<iBreak+10 ){
-      return aMatch[i].iStart;
-    }
-    if( i>0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){
-      return aMatch[i-1].iStart;
-    }
-  }
-  for(i=1; i<=10; i++){
-    if( safe_isspace(zDoc[iBreak-i]) ){
-      return iBreak - i + 1;
-    }
-    if( safe_isspace(zDoc[iBreak+i]) ){
-      return iBreak + i + 1;
-    }
+  fulltext_cursor *pCursor;
+  if( argc<1 ) return;
+  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to offsets",-1);
+  }else{
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    snippetAllOffsets(pCursor);
+    snippetOffsetText(&pCursor->snippet);
+    sqlite3_result_text(pContext,
+                        pCursor->snippet.zOffset, pCursor->snippet.nOffset,
+                        SQLITE_STATIC);
   }
-  return iBreak;
 }
 
-
-
-/*
-** Allowed values for Snippet.aMatch[].snStatus
+/* OptLeavesReader is nearly identical to LeavesReader, except that
+** where LeavesReader is geared towards the merging of complete
+** segment levels (with exactly MERGE_COUNT segments), OptLeavesReader
+** is geared towards implementation of the optimize() function, and
+** can merge all segments simultaneously.  This version may be
+** somewhat less efficient than LeavesReader because it merges into an
+** accumulator rather than doing an N-way merge, but since segment
+** size grows exponentially (so segment count logrithmically) this is
+** probably not an immediate problem.
 */
-#define SNIPPET_IGNORE  0   /* It is ok to omit this match from the snippet */
-#define SNIPPET_DESIRED 1   /* We want to include this match in the snippet */
+/* TODO(shess): Prove that assertion, or extend the merge code to
+** merge tree fashion (like the prefix-searching code does).
+*/
+/* TODO(shess): OptLeavesReader and LeavesReader could probably be
+** merged with little or no loss of performance for LeavesReader.  The
+** merged code would need to handle >MERGE_COUNT segments, and would
+** also need to be able to optionally optimize away deletes.
+*/
+typedef struct OptLeavesReader {
+  /* Segment number, to order readers by age. */
+  int segment;
+  LeavesReader reader;
+} OptLeavesReader;
 
-/*
-** Generate the text of a snippet.
+static int optLeavesReaderAtEnd(OptLeavesReader *pReader){
+  return leavesReaderAtEnd(&pReader->reader);
+}
+static int optLeavesReaderTermBytes(OptLeavesReader *pReader){
+  return leavesReaderTermBytes(&pReader->reader);
+}
+static const char *optLeavesReaderData(OptLeavesReader *pReader){
+  return leavesReaderData(&pReader->reader);
+}
+static int optLeavesReaderDataBytes(OptLeavesReader *pReader){
+  return leavesReaderDataBytes(&pReader->reader);
+}
+static const char *optLeavesReaderTerm(OptLeavesReader *pReader){
+  return leavesReaderTerm(&pReader->reader);
+}
+static int optLeavesReaderStep(fulltext_vtab *v, OptLeavesReader *pReader){
+  return leavesReaderStep(v, &pReader->reader);
+}
+static int optLeavesReaderTermCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
+  return leavesReaderTermCmp(&lr1->reader, &lr2->reader);
+}
+/* Order by term ascending, segment ascending (oldest to newest), with
+** exhausted readers to the end.
 */
-static void snippetText(
-  fulltext_cursor *pCursor,   /* The cursor we need the snippet for */
-  const char *zStartMark,     /* Markup to appear before each match */
-  const char *zEndMark,       /* Markup to appear after each match */
-  const char *zEllipsis       /* Ellipsis mark */
-){
-  int i, j;
-  struct snippetMatch *aMatch;
-  int nMatch;
-  int nDesired;
-  StringBuffer sb;
-  int tailCol;
-  int tailOffset;
-  int iCol;
-  int nDoc;
-  const char *zDoc;
-  int iStart, iEnd;
-  int tailEllipsis = 0;
-  int iMatch;
-  
+static int optLeavesReaderCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
+  int c = optLeavesReaderTermCmp(lr1, lr2);
+  if( c!=0 ) return c;
+  return lr1->segment-lr2->segment;
+}
+/* Bubble pLr[0] to appropriate place in pLr[1..nLr-1].  Assumes that
+** pLr[1..nLr-1] is already sorted.
+*/
+static void optLeavesReaderReorder(OptLeavesReader *pLr, int nLr){
+  while( nLr>1 && optLeavesReaderCmp(pLr, pLr+1)>0 ){
+    OptLeavesReader tmp = pLr[0];
+    pLr[0] = pLr[1];
+    pLr[1] = tmp;
+    nLr--;
+    pLr++;
+  }
+}
 
-  sqlite3_free(pCursor->snippet.zSnippet);
-  pCursor->snippet.zSnippet = 0;
-  aMatch = pCursor->snippet.aMatch;
-  nMatch = pCursor->snippet.nMatch;
-  initStringBuffer(&sb);
+/* optimize() helper function.  Put the readers in order and iterate
+** through them, merging doclists for matching terms into pWriter.
+** Returns SQLITE_OK on success, or the SQLite error code which
+** prevented success.
+*/
+static int optimizeInternal(fulltext_vtab *v,
+                            OptLeavesReader *readers, int nReaders,
+                            LeafWriter *pWriter){
+  int i, rc = SQLITE_OK;
+  DataBuffer doclist, merged, tmp;
 
-  for(i=0; i<nMatch; i++){
-    aMatch[i].snStatus = SNIPPET_IGNORE;
-  }
-  nDesired = 0;
-  for(i=0; i<pCursor->q.nTerms; i++){
-    for(j=0; j<nMatch; j++){
-      if( aMatch[j].iTerm==i ){
-        aMatch[j].snStatus = SNIPPET_DESIRED;
-        nDesired++;
-        break;
-      }
-    }
+  /* Order the readers. */
+  i = nReaders;
+  while( i-- > 0 ){
+    optLeavesReaderReorder(&readers[i], nReaders-i);
   }
 
-  iMatch = 0;
-  tailCol = -1;
-  tailOffset = 0;
-  for(i=0; i<nMatch && nDesired>0; i++){
-    if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue;
-    nDesired--;
-    iCol = aMatch[i].iCol;
-    zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1);
-    nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1);
-    iStart = aMatch[i].iStart - 40;
-    iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol);
-    if( iStart<=10 ){
-      iStart = 0;
-    }
-    if( iCol==tailCol && iStart<=tailOffset+20 ){
-      iStart = tailOffset;
-    }
-    if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){
-      trimWhiteSpace(&sb);
-      appendWhiteSpace(&sb);
-      append(&sb, zEllipsis);
-      appendWhiteSpace(&sb);
+  dataBufferInit(&doclist, LEAF_MAX);
+  dataBufferInit(&merged, LEAF_MAX);
+
+  /* Exhausted readers bubble to the end, so when the first reader is
+  ** at eof, all are at eof.
+  */
+  while( !optLeavesReaderAtEnd(&readers[0]) ){
+
+    /* Figure out how many readers share the next term. */
+    for(i=1; i<nReaders && !optLeavesReaderAtEnd(&readers[i]); i++){
+      if( 0!=optLeavesReaderTermCmp(&readers[0], &readers[i]) ) break;
     }
-    iEnd = aMatch[i].iStart + aMatch[i].nByte + 40;
-    iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol);
-    if( iEnd>=nDoc-10 ){
-      iEnd = nDoc;
-      tailEllipsis = 0;
+
+    /* Special-case for no merge. */
+    if( i==1 ){
+      /* Trim deletions from the doclist. */
+      dataBufferReset(&merged);
+      docListTrim(DL_DEFAULT,
+                  optLeavesReaderData(&readers[0]),
+                  optLeavesReaderDataBytes(&readers[0]),
+                  -1, DL_DEFAULT, &merged);
     }else{
-      tailEllipsis = 1;
-    }
-    while( iMatch<nMatch && aMatch[iMatch].iCol<iCol ){ iMatch++; }
-    while( iStart<iEnd ){
-      while( iMatch<nMatch && aMatch[iMatch].iStart<iStart
-             && aMatch[iMatch].iCol<=iCol ){
-        iMatch++;
-      }
-      if( iMatch<nMatch && aMatch[iMatch].iStart<iEnd
-             && aMatch[iMatch].iCol==iCol ){
-        nappend(&sb, &zDoc[iStart], aMatch[iMatch].iStart - iStart);
-        iStart = aMatch[iMatch].iStart;
-        append(&sb, zStartMark);
-        nappend(&sb, &zDoc[iStart], aMatch[iMatch].nByte);
-        append(&sb, zEndMark);
-        iStart += aMatch[iMatch].nByte;
-        for(j=iMatch+1; j<nMatch; j++){
-          if( aMatch[j].iTerm==aMatch[iMatch].iTerm
-              && aMatch[j].snStatus==SNIPPET_DESIRED ){
-            nDesired--;
-            aMatch[j].snStatus = SNIPPET_IGNORE;
-          }
+      DLReader dlReaders[MERGE_COUNT];
+      int iReader, nReaders;
+
+      /* Prime the pipeline with the first reader's doclist.  After
+      ** one pass index 0 will reference the accumulated doclist.
+      */
+      dlrInit(&dlReaders[0], DL_DEFAULT,
+              optLeavesReaderData(&readers[0]),
+              optLeavesReaderDataBytes(&readers[0]));
+      iReader = 1;
+
+      assert( iReader<i );  /* Must execute the loop at least once. */
+      while( iReader<i ){
+        /* Merge 16 inputs per pass. */
+        for( nReaders=1; iReader<i && nReaders<MERGE_COUNT;
+             iReader++, nReaders++ ){
+          dlrInit(&dlReaders[nReaders], DL_DEFAULT,
+                  optLeavesReaderData(&readers[iReader]),
+                  optLeavesReaderDataBytes(&readers[iReader]));
         }
-      }else{
-        nappend(&sb, &zDoc[iStart], iEnd - iStart);
-        iStart = iEnd;
-      }
-    }
-    tailCol = iCol;
-    tailOffset = iEnd;
-  }
-  trimWhiteSpace(&sb);
-  if( tailEllipsis ){
-    appendWhiteSpace(&sb);
-    append(&sb, zEllipsis);
-  }
-  pCursor->snippet.zSnippet = stringBufferData(&sb);
-  pCursor->snippet.nSnippet = stringBufferLength(&sb);
-}
 
+        /* Merge doclists and swap result into accumulator. */
+        dataBufferReset(&merged);
+        docListMerge(&merged, dlReaders, nReaders);
+        tmp = merged;
+        merged = doclist;
+        doclist = tmp;
 
-/*
-** Close the cursor.  For additional information see the documentation
-** on the xClose method of the virtual table interface.
-*/
-static int fulltextClose(sqlite3_vtab_cursor *pCursor){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  FTSTRACE(("FTS3 Close %p\n", c));
-  sqlite3_finalize(c->pStmt);
-  queryClear(&c->q);
-  snippetClear(&c->snippet);
-  if( c->result.nData!=0 ) dlrDestroy(&c->reader);
-  dataBufferDestroy(&c->result);
-  sqlite3_free(c);
-  return SQLITE_OK;
-}
+        while( nReaders-- > 0 ){
+          dlrDestroy(&dlReaders[nReaders]);
+        }
 
-static int fulltextNext(sqlite3_vtab_cursor *pCursor){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  int rc;
+        /* Accumulated doclist to reader 0 for next pass. */
+        dlrInit(&dlReaders[0], DL_DEFAULT, doclist.pData, doclist.nData);
+      }
 
-  FTSTRACE(("FTS3 Next %p\n", pCursor));
-  snippetClear(&c->snippet);
-  if( c->iCursorType < QUERY_FULLTEXT ){
-    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
-    rc = sqlite3_step(c->pStmt);
-    switch( rc ){
-      case SQLITE_ROW:
-        c->eof = 0;
-        return SQLITE_OK;
-      case SQLITE_DONE:
-        c->eof = 1;
-        return SQLITE_OK;
-      default:
-        c->eof = 1;
-        return rc;
+      /* Destroy reader that was left in the pipeline. */
+      dlrDestroy(&dlReaders[0]);
+
+      /* Trim deletions from the doclist. */
+      dataBufferReset(&merged);
+      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
+                  -1, DL_DEFAULT, &merged);
     }
-  } else {  /* full-text query */
-    rc = sqlite3_reset(c->pStmt);
-    if( rc!=SQLITE_OK ) return rc;
 
-    if( c->result.nData==0 || dlrAtEnd(&c->reader) ){
-      c->eof = 1;
-      return SQLITE_OK;
+    /* Only pass doclists with hits (skip if all hits deleted). */
+    if( merged.nData>0 ){
+      rc = leafWriterStep(v, pWriter,
+                          optLeavesReaderTerm(&readers[0]),
+                          optLeavesReaderTermBytes(&readers[0]),
+                          merged.pData, merged.nData);
+      if( rc!=SQLITE_OK ) goto err;
     }
-    rc = sqlite3_bind_int64(c->pStmt, 1, dlrDocid(&c->reader));
-    dlrStep(&c->reader);
-    if( rc!=SQLITE_OK ) return rc;
-    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
-    rc = sqlite3_step(c->pStmt);
-    if( rc==SQLITE_ROW ){   /* the case we expect */
-      c->eof = 0;
-      return SQLITE_OK;
+
+    /* Step merged readers to next term and reorder. */
+    while( i-- > 0 ){
+      rc = optLeavesReaderStep(v, &readers[i]);
+      if( rc!=SQLITE_OK ) goto err;
+
+      optLeavesReaderReorder(&readers[i], nReaders-i);
     }
-    /* an error occurred; abort */
-    return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
   }
-}
-
 
-/* TODO(shess) If we pushed LeafReader to the top of the file, or to
-** another file, term_select() could be pushed above
-** docListOfTerm().
-*/
-static int termSelect(fulltext_vtab *v, int iColumn,
-                      const char *pTerm, int nTerm, int isPrefix,
-                      DocListType iType, DataBuffer *out);
+ err:
+  dataBufferDestroy(&doclist);
+  dataBufferDestroy(&merged);
+  return rc;
+}
 
-/* Return a DocList corresponding to the query term *pTerm.  If *pTerm
-** is the first term of a phrase query, go ahead and evaluate the phrase
-** query and return the doclist for the entire phrase query.
-**
-** The resulting DL_DOCIDS doclist is stored in pResult, which is
-** overwritten.
+/* Implement optimize() function for FTS3.  optimize(t) merges all
+** segments in the fts index into a single segment.  't' is the magic
+** table-named column.
 */
-static int docListOfTerm(
-  fulltext_vtab *v,    /* The full text index */
-  int iColumn,         /* column to restrict to.  No restriction if >=nColumn */
-  QueryTerm *pQTerm,   /* Term we are looking for, or 1st term of a phrase */
-  DataBuffer *pResult  /* Write the result here */
-){
-  DataBuffer left, right, new;
-  int i, rc;
-
-  /* No phrase search if no position info. */
-  assert( pQTerm->nPhrase==0 || DL_DEFAULT!=DL_DOCIDS );
+static void optimizeFunc(sqlite3_context *pContext,
+                         int argc, sqlite3_value **argv){
+  fulltext_cursor *pCursor;
+  if( argc>1 ){
+    sqlite3_result_error(pContext, "excess arguments to optimize()",-1);
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to optimize",-1);
+  }else{
+    fulltext_vtab *v;
+    int i, rc, iMaxLevel;
+    OptLeavesReader *readers;
+    int nReaders;
+    LeafWriter writer;
+    sqlite3_stmt *s;
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-  dataBufferInit(&left, 0);
-  rc = termSelect(v, iColumn, pQTerm->pTerm, pQTerm->nTerm, pQTerm->isPrefix,
-                  (0<pQTerm->nPhrase ? DL_POSITIONS : DL_DOCIDS), &left);
-  if( rc ) return rc;
-  for(i=1; i<=pQTerm->nPhrase && left.nData>0; i++){
-    /* If this token is connected to the next by a NEAR operator, and
-    ** the next token is the start of a phrase, then set nPhraseRight
-    ** to the number of tokens in the phrase. Otherwise leave it at 1.
-    */
-    int nPhraseRight = 1;
-    while( (i+nPhraseRight)<=pQTerm->nPhrase 
-        && pQTerm[i+nPhraseRight].nNear==0 
-    ){
-      nPhraseRight++;
-    }
+    /* Flush any buffered updates before optimizing. */
+    rc = flushPendingTerms(v);
+    if( rc!=SQLITE_OK ) goto err;
 
-    dataBufferInit(&right, 0);
-    rc = termSelect(v, iColumn, pQTerm[i].pTerm, pQTerm[i].nTerm,
-                    pQTerm[i].isPrefix, DL_POSITIONS, &right);
-    if( rc ){
-      dataBufferDestroy(&left);
-      return rc;
+    rc = segdir_count(v, &nReaders, &iMaxLevel);
+    if( rc!=SQLITE_OK ) goto err;
+    if( nReaders==0 || nReaders==1 ){
+      sqlite3_result_text(pContext, "Index already optimal", -1,
+                          SQLITE_STATIC);
+      return;
     }
-    dataBufferInit(&new, 0);
-    docListPhraseMerge(left.pData, left.nData, right.pData, right.nData,
-                       pQTerm[i-1].nNear, pQTerm[i-1].iPhrase + nPhraseRight,
-                       ((i<pQTerm->nPhrase) ? DL_POSITIONS : DL_DOCIDS),
-                       &new);
-    dataBufferDestroy(&left);
-    dataBufferDestroy(&right);
-    left = new;
-  }
-  *pResult = left;
-  return SQLITE_OK;
-}
 
-/* Add a new term pTerm[0..nTerm-1] to the query *q.
-*/
-static void queryAdd(Query *q, const char *pTerm, int nTerm){
-  QueryTerm *t;
-  ++q->nTerms;
-  q->pTerms = sqlite3_realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0]));
-  if( q->pTerms==0 ){
-    q->nTerms = 0;
-    return;
-  }
-  t = &q->pTerms[q->nTerms - 1];
-  CLEAR(t);
-  t->pTerm = sqlite3_malloc(nTerm+1);
-  memcpy(t->pTerm, pTerm, nTerm);
-  t->pTerm[nTerm] = 0;
-  t->nTerm = nTerm;
-  t->isOr = q->nextIsOr;
-  t->isPrefix = 0;
-  q->nextIsOr = 0;
-  t->iColumn = q->nextColumn;
-  q->nextColumn = q->dfltColumn;
-}
-
-/*
-** Check to see if the string zToken[0...nToken-1] matches any
-** column name in the virtual table.   If it does,
-** return the zero-indexed column number.  If not, return -1.
-*/
-static int checkColumnSpecifier(
-  fulltext_vtab *pVtab,    /* The virtual table */
-  const char *zToken,      /* Text of the token */
-  int nToken               /* Number of characters in the token */
-){
-  int i;
-  for(i=0; i<pVtab->nColumn; i++){
-    if( memcmp(pVtab->azColumn[i], zToken, nToken)==0
-        && pVtab->azColumn[i][nToken]==0 ){
-      return i;
-    }
-  }
-  return -1;
-}
+    rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
+    if( rc!=SQLITE_OK ) goto err;
 
-/*
-** Parse the text at pSegment[0..nSegment-1].  Add additional terms
-** to the query being assemblied in pQuery.
-**
-** inPhrase is true if pSegment[0..nSegement-1] is contained within
-** double-quotes.  If inPhrase is true, then the first term
-** is marked with the number of terms in the phrase less one and
-** OR and "-" syntax is ignored.  If inPhrase is false, then every
-** term found is marked with nPhrase=0 and OR and "-" syntax is significant.
-*/
-static int tokenizeSegment(
-  sqlite3_tokenizer *pTokenizer,          /* The tokenizer to use */
-  const char *pSegment, int nSegment,     /* Query expression being parsed */
-  int inPhrase,                           /* True if within "..." */
-  Query *pQuery                           /* Append results here */
-){
-  const sqlite3_tokenizer_module *pModule = pTokenizer->pModule;
-  sqlite3_tokenizer_cursor *pCursor;
-  int firstIndex = pQuery->nTerms;
-  int iCol;
-  int nTerm = 1;
-  
-  int rc = pModule->xOpen(pTokenizer, pSegment, nSegment, &pCursor);
-  if( rc!=SQLITE_OK ) return rc;
-  pCursor->pTokenizer = pTokenizer;
+    readers = sqlite3_malloc(nReaders*sizeof(readers[0]));
+    if( readers==NULL ) goto err;
 
-  while( 1 ){
-    const char *pToken;
-    int nToken, iBegin, iEnd, iPos;
+    /* Note that there will already be a segment at this position
+    ** until we call segdir_delete() on iMaxLevel.
+    */
+    leafWriterInit(iMaxLevel, 0, &writer);
 
-    rc = pModule->xNext(pCursor,
-                        &pToken, &nToken,
-                        &iBegin, &iEnd, &iPos);
-    if( rc!=SQLITE_OK ) break;
-    if( !inPhrase &&
-        pSegment[iEnd]==':' &&
-         (iCol = checkColumnSpecifier(pQuery->pFts, pToken, nToken))>=0 ){
-      pQuery->nextColumn = iCol;
-      continue;
-    }
-    if( !inPhrase && pQuery->nTerms>0 && nToken==2 
-     && pSegment[iBegin+0]=='O'
-     && pSegment[iBegin+1]=='R' 
-    ){
-      pQuery->nextIsOr = 1;
-      continue;
+    i = 0;
+    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+      sqlite_int64 iStart = sqlite3_column_int64(s, 0);
+      sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
+      const char *pRootData = sqlite3_column_blob(s, 2);
+      int nRootData = sqlite3_column_bytes(s, 2);
+
+      assert( i<nReaders );
+      rc = leavesReaderInit(v, -1, iStart, iEnd, pRootData, nRootData,
+                            &readers[i].reader);
+      if( rc!=SQLITE_OK ) break;
+
+      readers[i].segment = i;
+      i++;
     }
-    if( !inPhrase && pQuery->nTerms>0 && !pQuery->nextIsOr && nToken==4 
-      && pSegment[iBegin+0]=='N' 
-      && pSegment[iBegin+1]=='E' 
-      && pSegment[iBegin+2]=='A' 
-      && pSegment[iBegin+3]=='R' 
-    ){
-      QueryTerm *pTerm = &pQuery->pTerms[pQuery->nTerms-1];
-      if( (iBegin+6)<nSegment 
-       && pSegment[iBegin+4] == '/'
-       && pSegment[iBegin+5]>='0' && pSegment[iBegin+5]<='9'
-      ){
-        pTerm->nNear = (pSegment[iBegin+5] - '0');
-        nToken += 2;
-        if( pSegment[iBegin+6]>='0' && pSegment[iBegin+6]<=9 ){
-          pTerm->nNear = pTerm->nNear * 10 + (pSegment[iBegin+6] - '0');
-          iEnd++;
-        }
-        pModule->xNext(pCursor, &pToken, &nToken, &iBegin, &iEnd, &iPos);
-      } else {
-        pTerm->nNear = SQLITE_FTS3_DEFAULT_NEAR_PARAM;
-      }
-      pTerm->nNear++;
-      continue;
+
+    /* If we managed to successfully read them all, optimize them. */
+    if( rc==SQLITE_DONE ){
+      assert( i==nReaders );
+      rc = optimizeInternal(v, readers, nReaders, &writer);
     }
 
-    queryAdd(pQuery, pToken, nToken);
-    if( !inPhrase && iBegin>0 && pSegment[iBegin-1]=='-' ){
-      pQuery->pTerms[pQuery->nTerms-1].isNot = 1;
+    while( i-- > 0 ){
+      leavesReaderDestroy(&readers[i].reader);
     }
-    if( iEnd<nSegment && pSegment[iEnd]=='*' ){
-      pQuery->pTerms[pQuery->nTerms-1].isPrefix = 1;
+    sqlite3_free(readers);
+
+    /* If we've successfully gotten to here, delete the old segments
+    ** and flush the interior structure of the new segment.
+    */
+    if( rc==SQLITE_OK ){
+      for( i=0; i<=iMaxLevel; i++ ){
+        rc = segdir_delete(v, i);
+        if( rc!=SQLITE_OK ) break;
+      }
+
+      if( rc==SQLITE_OK ) rc = leafWriterFinalize(v, &writer);
     }
-    pQuery->pTerms[pQuery->nTerms-1].iPhrase = nTerm;
-    if( inPhrase ){
-      nTerm++;
+
+    leafWriterDestroy(&writer);
+
+    if( rc!=SQLITE_OK ) goto err;
+
+    sqlite3_result_text(pContext, "Index optimized", -1, SQLITE_STATIC);
+    return;
+
+    /* TODO(shess): Error-handling needs to be improved along the
+    ** lines of the dump_ functions.
+    */
+ err:
+    {
+      char buf[512];
+      sqlite3_snprintf(sizeof(buf), buf, "Error in optimize: %s",
+                       sqlite3_errmsg(sqlite3_context_db_handle(pContext)));
+      sqlite3_result_error(pContext, buf, -1);
     }
   }
+}
+
+#ifdef SQLITE_TEST
+/* Generate an error of the form "<prefix>: <msg>".  If msg is NULL,
+** pull the error from the context's db handle.
+*/
+static void generateError(sqlite3_context *pContext,
+                          const char *prefix, const char *msg){
+  char buf[512];
+  if( msg==NULL ) msg = sqlite3_errmsg(sqlite3_context_db_handle(pContext));
+  sqlite3_snprintf(sizeof(buf), buf, "%s: %s", prefix, msg);
+  sqlite3_result_error(pContext, buf, -1);
+}
+
+/* Helper function to collect the set of terms in the segment into
+** pTerms.  The segment is defined by the leaf nodes between
+** iStartBlockid and iEndBlockid, inclusive, or by the contents of
+** pRootData if iStartBlockid is 0 (in which case the entire segment
+** fit in a leaf).
+*/
+static int collectSegmentTerms(fulltext_vtab *v, sqlite3_stmt *s,
+                               fts3Hash *pTerms){
+  const sqlite_int64 iStartBlockid = sqlite3_column_int64(s, 0);
+  const sqlite_int64 iEndBlockid = sqlite3_column_int64(s, 1);
+  const char *pRootData = sqlite3_column_blob(s, 2);
+  const int nRootData = sqlite3_column_bytes(s, 2);
+  LeavesReader reader;
+  int rc = leavesReaderInit(v, 0, iStartBlockid, iEndBlockid,
+                            pRootData, nRootData, &reader);
+  if( rc!=SQLITE_OK ) return rc;
 
-  if( inPhrase && pQuery->nTerms>firstIndex ){
-    pQuery->pTerms[firstIndex].nPhrase = pQuery->nTerms - firstIndex - 1;
+  while( rc==SQLITE_OK && !leavesReaderAtEnd(&reader) ){
+    const char *pTerm = leavesReaderTerm(&reader);
+    const int nTerm = leavesReaderTermBytes(&reader);
+    void *oldValue = sqlite3Fts3HashFind(pTerms, pTerm, nTerm);
+    void *newValue = (void *)((char *)oldValue+1);
+
+    /* From the comment before sqlite3Fts3HashInsert in fts3_hash.c,
+    ** the data value passed is returned in case of malloc failure.
+    */
+    if( newValue==sqlite3Fts3HashInsert(pTerms, pTerm, nTerm, newValue) ){
+      rc = SQLITE_NOMEM;
+    }else{
+      rc = leavesReaderStep(v, &reader);
+    }
   }
 
-  return pModule->xClose(pCursor);
+  leavesReaderDestroy(&reader);
+  return rc;
 }
 
-/* Parse a query string, yielding a Query object pQuery.
-**
-** The calling function will need to queryClear() to clean up
-** the dynamically allocated memory held by pQuery.
-*/
-static int parseQuery(
-  fulltext_vtab *v,        /* The fulltext index */
-  const char *zInput,      /* Input text of the query string */
-  int nInput,              /* Size of the input text */
-  int dfltColumn,          /* Default column of the index to match against */
-  Query *pQuery            /* Write the parse results here. */
-){
-  int iInput, inPhrase = 0;
-  int ii;
-  QueryTerm *aTerm;
-
-  if( zInput==0 ) nInput = 0;
-  if( nInput<0 ) nInput = strlen(zInput);
-  pQuery->nTerms = 0;
-  pQuery->pTerms = NULL;
-  pQuery->nextIsOr = 0;
-  pQuery->nextColumn = dfltColumn;
-  pQuery->dfltColumn = dfltColumn;
-  pQuery->pFts = v;
-
-  for(iInput=0; iInput<nInput; ++iInput){
-    int i;
-    for(i=iInput; i<nInput && zInput[i]!='"'; ++i){}
-    if( i>iInput ){
-      tokenizeSegment(v->pTokenizer, zInput+iInput, i-iInput, inPhrase,
-                       pQuery);
-    }
-    iInput = i;
-    if( i<nInput ){
-      assert( zInput[i]=='"' );
-      inPhrase = !inPhrase;
-    }
+/* Helper function to build the result string for dump_terms(). */
+static int generateTermsResult(sqlite3_context *pContext, fts3Hash *pTerms){
+  int iTerm, nTerms, nResultBytes, iByte;
+  char *result;
+  TermData *pData;
+  fts3HashElem *e;
+
+  /* Iterate pTerms to generate an array of terms in pData for
+  ** sorting.
+  */
+  nTerms = fts3HashCount(pTerms);
+  assert( nTerms>0 );
+  pData = sqlite3_malloc(nTerms*sizeof(TermData));
+  if( pData==NULL ) return SQLITE_NOMEM;
+
+  nResultBytes = 0;
+  for(iTerm = 0, e = fts3HashFirst(pTerms); e; iTerm++, e = fts3HashNext(e)){
+    nResultBytes += fts3HashKeysize(e)+1;   /* Term plus trailing space */
+    assert( iTerm<nTerms );
+    pData[iTerm].pTerm = fts3HashKey(e);
+    pData[iTerm].nTerm = fts3HashKeysize(e);
+    pData[iTerm].pCollector = fts3HashData(e);  /* unused */
   }
+  assert( iTerm==nTerms );
 
-  if( inPhrase ){
-    /* unmatched quote */
-    queryClear(pQuery);
-    return SQLITE_ERROR;
+  assert( nResultBytes>0 );   /* nTerms>0, nResultsBytes must be, too. */
+  result = sqlite3_malloc(nResultBytes);
+  if( result==NULL ){
+    sqlite3_free(pData);
+    return SQLITE_NOMEM;
   }
 
-  /* Modify the values of the QueryTerm.nPhrase variables to account for
-  ** the NEAR operator. For the purposes of QueryTerm.nPhrase, phrases
-  ** and tokens connected by the NEAR operator are handled as a single
-  ** phrase. See comments above the QueryTerm structure for details.
-  */
-  aTerm = pQuery->pTerms;
-  for(ii=0; ii<pQuery->nTerms; ii++){
-    if( aTerm[ii].nNear || aTerm[ii].nPhrase ){
-      while (aTerm[ii+aTerm[ii].nPhrase].nNear) {
-        aTerm[ii].nPhrase += (1 + aTerm[ii+aTerm[ii].nPhrase+1].nPhrase);
-      }
-    }
+  if( nTerms>1 ) qsort(pData, nTerms, sizeof(*pData), termDataCmp);
+
+  /* Read the terms in order to build the result. */
+  iByte = 0;
+  for(iTerm=0; iTerm<nTerms; ++iTerm){
+    memcpy(result+iByte, pData[iTerm].pTerm, pData[iTerm].nTerm);
+    iByte += pData[iTerm].nTerm;
+    result[iByte++] = ' ';
   }
+  assert( iByte==nResultBytes );
+  assert( result[nResultBytes-1]==' ' );
+  result[nResultBytes-1] = '\0';
 
+  /* Passes away ownership of result. */
+  sqlite3_result_text(pContext, result, nResultBytes-1, sqlite3_free);
+  sqlite3_free(pData);
   return SQLITE_OK;
 }
 
-/* TODO(shess) Refactor the code to remove this forward decl. */
-static int flushPendingTerms(fulltext_vtab *v);
-
-/* Perform a full-text query using the search expression in
-** zInput[0..nInput-1].  Return a list of matching documents
-** in pResult.
-**
-** Queries must match column iColumn.  Or if iColumn>=nColumn
-** they are allowed to match against any column.
+/* Implements dump_terms() for use in inspecting the fts3 index from
+** tests.  TEXT result containing the ordered list of terms joined by
+** spaces.  dump_terms(t, level, idx) dumps the terms for the segment
+** specified by level, idx (in %_segdir), while dump_terms(t) dumps
+** all terms in the index.  In both cases t is the fts table's magic
+** table-named column.
 */
-static int fulltextQuery(
-  fulltext_vtab *v,      /* The full text index */
-  int iColumn,           /* Match against this column by default */
-  const char *zInput,    /* The query string */
-  int nInput,            /* Number of bytes in zInput[] */
-  DataBuffer *pResult,   /* Write the result doclist here */
-  Query *pQuery          /* Put parsed query string here */
+static void dumpTermsFunc(
+  sqlite3_context *pContext,
+  int argc, sqlite3_value **argv
 ){
-  int i, iNext, rc;
-  DataBuffer left, right, or, new;
-  int nNot = 0;
-  QueryTerm *aTerm;
-
-  /* TODO(shess) Instead of flushing pendingTerms, we could query for
-  ** the relevant term and merge the doclist into what we receive from
-  ** the database.  Wait and see if this is a common issue, first.
-  **
-  ** A good reason not to flush is to not generate update-related
-  ** error codes from here.
-  */
-
-  /* Flush any buffered updates before executing the query. */
-  rc = flushPendingTerms(v);
-  if( rc!=SQLITE_OK ) return rc;
-
-  /* TODO(shess) I think that the queryClear() calls below are not
-  ** necessary, because fulltextClose() already clears the query.
-  */
-  rc = parseQuery(v, zInput, nInput, iColumn, pQuery);
-  if( rc!=SQLITE_OK ) return rc;
+  fulltext_cursor *pCursor;
+  if( argc!=3 && argc!=1 ){
+    generateError(pContext, "dump_terms", "incorrect arguments");
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    generateError(pContext, "dump_terms", "illegal first argument");
+  }else{
+    fulltext_vtab *v;
+    fts3Hash terms;
+    sqlite3_stmt *s = NULL;
+    int rc;
 
-  /* Empty or NULL queries return no results. */
-  if( pQuery->nTerms==0 ){
-    dataBufferInit(pResult, 0);
-    return SQLITE_OK;
-  }
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-  /* Merge AND terms. */
-  /* TODO(shess) I think we can early-exit if( i>nNot && left.nData==0 ). */
-  aTerm = pQuery->pTerms;
-  for(i = 0; i<pQuery->nTerms; i=iNext){
-    if( aTerm[i].isNot ){
-      /* Handle all NOT terms in a separate pass */
-      nNot++;
-      iNext = i + aTerm[i].nPhrase+1;
-      continue;
+    /* If passed only the cursor column, get all segments.  Otherwise
+    ** get the segment described by the following two arguments.
+    */
+    if( argc==1 ){
+      rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
+    }else{
+      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[1]));
+        if( rc==SQLITE_OK ){
+          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[2]));
+        }
+      }
     }
-    iNext = i + aTerm[i].nPhrase + 1;
-    rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
-    if( rc ){
-      if( i!=nNot ) dataBufferDestroy(&left);
-      queryClear(pQuery);
-      return rc;
+
+    if( rc!=SQLITE_OK ){
+      generateError(pContext, "dump_terms", NULL);
+      return;
     }
-    while( iNext<pQuery->nTerms && aTerm[iNext].isOr ){
-      rc = docListOfTerm(v, aTerm[iNext].iColumn, &aTerm[iNext], &or);
-      iNext += aTerm[iNext].nPhrase + 1;
-      if( rc ){
-        if( i!=nNot ) dataBufferDestroy(&left);
-        dataBufferDestroy(&right);
-        queryClear(pQuery);
-        return rc;
-      }
-      dataBufferInit(&new, 0);
-      docListOrMerge(right.pData, right.nData, or.pData, or.nData, &new);
-      dataBufferDestroy(&right);
-      dataBufferDestroy(&or);
-      right = new;
+
+    /* Collect the terms for each segment. */
+    sqlite3Fts3HashInit(&terms, FTS3_HASH_STRING, 1);
+    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+      rc = collectSegmentTerms(v, s, &terms);
+      if( rc!=SQLITE_OK ) break;
     }
-    if( i==nNot ){           /* first term processed. */
-      left = right;
+
+    if( rc!=SQLITE_DONE ){
+      sqlite3_reset(s);
+      generateError(pContext, "dump_terms", NULL);
     }else{
-      dataBufferInit(&new, 0);
-      docListAndMerge(left.pData, left.nData, right.pData, right.nData, &new);
-      dataBufferDestroy(&right);
-      dataBufferDestroy(&left);
-      left = new;
+      const int nTerms = fts3HashCount(&terms);
+      if( nTerms>0 ){
+        rc = generateTermsResult(pContext, &terms);
+        if( rc==SQLITE_NOMEM ){
+          generateError(pContext, "dump_terms", "out of memory");
+        }else{
+          assert( rc==SQLITE_OK );
+        }
+      }else if( argc==3 ){
+        /* The specific segment asked for could not be found. */
+        generateError(pContext, "dump_terms", "segment not found");
+      }else{
+        /* No segments found. */
+        /* TODO(shess): It should be impossible to reach this.  This
+        ** case can only happen for an empty table, in which case
+        ** SQLite has no rows to call this function on.
+        */
+        sqlite3_result_null(pContext);
+      }
     }
+    sqlite3Fts3HashClear(&terms);
   }
+}
 
-  if( nNot==pQuery->nTerms ){
-    /* We do not yet know how to handle a query of only NOT terms */
-    return SQLITE_ERROR;
-  }
+/* Expand the DL_DEFAULT doclist in pData into a text result in
+** pContext.
+*/
+static void createDoclistResult(sqlite3_context *pContext,
+                                const char *pData, int nData){
+  DataBuffer dump;
+  DLReader dlReader;
 
-  /* Do the EXCEPT terms */
-  for(i=0; i<pQuery->nTerms;  i += aTerm[i].nPhrase + 1){
-    if( !aTerm[i].isNot ) continue;
-    rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
-    if( rc ){
-      queryClear(pQuery);
-      dataBufferDestroy(&left);
-      return rc;
+  assert( pData!=NULL && nData>0 );
+
+  dataBufferInit(&dump, 0);
+  dlrInit(&dlReader, DL_DEFAULT, pData, nData);
+  for( ; !dlrAtEnd(&dlReader); dlrStep(&dlReader) ){
+    char buf[256];
+    PLReader plReader;
+
+    plrInit(&plReader, &dlReader);
+    if( DL_DEFAULT==DL_DOCIDS || plrAtEnd(&plReader) ){
+      sqlite3_snprintf(sizeof(buf), buf, "[%lld] ", dlrDocid(&dlReader));
+      dataBufferAppend(&dump, buf, strlen(buf));
+    }else{
+      int iColumn = plrColumn(&plReader);
+
+      sqlite3_snprintf(sizeof(buf), buf, "[%lld %d[",
+                       dlrDocid(&dlReader), iColumn);
+      dataBufferAppend(&dump, buf, strlen(buf));
+
+      for( ; !plrAtEnd(&plReader); plrStep(&plReader) ){
+        if( plrColumn(&plReader)!=iColumn ){
+          iColumn = plrColumn(&plReader);
+          sqlite3_snprintf(sizeof(buf), buf, "] %d[", iColumn);
+          assert( dump.nData>0 );
+          dump.nData--;                     /* Overwrite trailing space. */
+          assert( dump.pData[dump.nData]==' ');
+          dataBufferAppend(&dump, buf, strlen(buf));
+        }
+        if( DL_DEFAULT==DL_POSITIONS_OFFSETS ){
+          sqlite3_snprintf(sizeof(buf), buf, "%d,%d,%d ",
+                           plrPosition(&plReader),
+                           plrStartOffset(&plReader), plrEndOffset(&plReader));
+        }else if( DL_DEFAULT==DL_POSITIONS ){
+          sqlite3_snprintf(sizeof(buf), buf, "%d ", plrPosition(&plReader));
+        }else{
+          assert( NULL=="Unhandled DL_DEFAULT value");
+        }
+        dataBufferAppend(&dump, buf, strlen(buf));
+      }
+      plrDestroy(&plReader);
+
+      assert( dump.nData>0 );
+      dump.nData--;                     /* Overwrite trailing space. */
+      assert( dump.pData[dump.nData]==' ');
+      dataBufferAppend(&dump, "]] ", 3);
     }
-    dataBufferInit(&new, 0);
-    docListExceptMerge(left.pData, left.nData, right.pData, right.nData, &new);
-    dataBufferDestroy(&right);
-    dataBufferDestroy(&left);
-    left = new;
   }
+  dlrDestroy(&dlReader);
 
-  *pResult = left;
-  return rc;
+  assert( dump.nData>0 );
+  dump.nData--;                     /* Overwrite trailing space. */
+  assert( dump.pData[dump.nData]==' ');
+  dump.pData[dump.nData] = '\0';
+  assert( dump.nData>0 );
+
+  /* Passes ownership of dump's buffer to pContext. */
+  sqlite3_result_text(pContext, dump.pData, dump.nData, sqlite3_free);
+  dump.pData = NULL;
+  dump.nData = dump.nCapacity = 0;
 }
 
-/*
-** This is the xFilter interface for the virtual table.  See
-** the virtual table xFilter method documentation for additional
-** information.
+/* Implements dump_doclist() for use in inspecting the fts3 index from
+** tests.  TEXT result containing a string representation of the
+** doclist for the indicated term.  dump_doclist(t, term, level, idx)
+** dumps the doclist for term from the segment specified by level, idx
+** (in %_segdir), while dump_doclist(t, term) dumps the logical
+** doclist for the term across all segments.  The per-segment doclist
+** can contain deletions, while the full-index doclist will not
+** (deletions are omitted).
 **
-** If idxNum==QUERY_GENERIC then do a full table scan against
-** the %_content table.
+** Result formats differ with the setting of DL_DEFAULTS.  Examples:
 **
-** If idxNum==QUERY_DOCID then do a docid lookup for a single entry
-** in the %_content table.
+** DL_DOCIDS: [1] [3] [7]
+** DL_POSITIONS: [1 0[0 4] 1[17]] [3 1[5]]
+** DL_POSITIONS_OFFSETS: [1 0[0,0,3 4,23,26] 1[17,102,105]] [3 1[5,20,23]]
 **
-** If idxNum>=QUERY_FULLTEXT then use the full text index.  The
-** column on the left-hand side of the MATCH operator is column
-** number idxNum-QUERY_FULLTEXT, 0 indexed.  argv[0] is the right-hand
-** side of the MATCH operator.
-*/
-/* TODO(shess) Upgrade the cursor initialization and destruction to
-** account for fulltextFilter() being called multiple times on the
-** same cursor.  The current solution is very fragile.  Apply fix to
-** fts3 as appropriate.
+** In each case the number after the outer '[' is the docid.  In the
+** latter two cases, the number before the inner '[' is the column
+** associated with the values within.  For DL_POSITIONS the numbers
+** within are the positions, for DL_POSITIONS_OFFSETS they are the
+** position, the start offset, and the end offset.
 */
-static int fulltextFilter(
-  sqlite3_vtab_cursor *pCursor,     /* The cursor used for this query */
-  int idxNum, const char *idxStr,   /* Which indexing scheme to use */
-  int argc, sqlite3_value **argv    /* Arguments for the indexing scheme */
+static void dumpDoclistFunc(
+  sqlite3_context *pContext,
+  int argc, sqlite3_value **argv
 ){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  fulltext_vtab *v = cursor_vtab(c);
-  int rc;
-  StringBuffer sb;
+  fulltext_cursor *pCursor;
+  if( argc!=2 && argc!=4 ){
+    generateError(pContext, "dump_doclist", "incorrect arguments");
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    generateError(pContext, "dump_doclist", "illegal first argument");
+  }else if( sqlite3_value_text(argv[1])==NULL ||
+            sqlite3_value_text(argv[1])[0]=='\0' ){
+    generateError(pContext, "dump_doclist", "empty second argument");
+  }else{
+    const char *pTerm = (const char *)sqlite3_value_text(argv[1]);
+    const int nTerm = strlen(pTerm);
+    fulltext_vtab *v;
+    int rc;
+    DataBuffer doclist;
 
-  FTSTRACE(("FTS3 Filter %p\n",pCursor));
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-  initStringBuffer(&sb);
-  append(&sb, "SELECT docid, ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, " FROM %_content");
-  if( idxNum!=QUERY_GENERIC ) append(&sb, " WHERE docid = ?");
-  sqlite3_finalize(c->pStmt);
-  rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt, stringBufferData(&sb));
-  stringBufferDestroy(&sb);
-  if( rc!=SQLITE_OK ) return rc;
+    dataBufferInit(&doclist, 0);
 
-  c->iCursorType = idxNum;
-  switch( idxNum ){
-    case QUERY_GENERIC:
-      break;
+    /* termSelect() yields the same logical doclist that queries are
+    ** run against.
+    */
+    if( argc==2 ){
+      rc = termSelect(v, v->nColumn, pTerm, nTerm, 0, DL_DEFAULT, &doclist);
+    }else{
+      sqlite3_stmt *s = NULL;
 
-    case QUERY_DOCID:
-      rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
-      if( rc!=SQLITE_OK ) return rc;
-      break;
+      /* Get our specific segment's information. */
+      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[2]));
+        if( rc==SQLITE_OK ){
+          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[3]));
+        }
+      }
 
-    default:   /* full-text search */
-    {
-      const char *zQuery = (const char *)sqlite3_value_text(argv[0]);
-      assert( idxNum<=QUERY_FULLTEXT+v->nColumn);
-      assert( argc==1 );
-      queryClear(&c->q);
-      if( c->result.nData!=0 ){
-        /* This case happens if the same cursor is used repeatedly. */
-        dlrDestroy(&c->reader);
-        dataBufferReset(&c->result);
-      }else{
-        dataBufferInit(&c->result, 0);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_step(s);
+
+        if( rc==SQLITE_DONE ){
+          dataBufferDestroy(&doclist);
+          generateError(pContext, "dump_doclist", "segment not found");
+          return;
+        }
+
+        /* Found a segment, load it into doclist. */
+        if( rc==SQLITE_ROW ){
+          const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
+          const char *pData = sqlite3_column_blob(s, 2);
+          const int nData = sqlite3_column_bytes(s, 2);
+
+          /* loadSegment() is used by termSelect() to load each
+          ** segment's data.
+          */
+          rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, 0,
+                           &doclist);
+          if( rc==SQLITE_OK ){
+            rc = sqlite3_step(s);
+
+            /* Should not have more than one matching segment. */
+            if( rc!=SQLITE_DONE ){
+              sqlite3_reset(s);
+              dataBufferDestroy(&doclist);
+              generateError(pContext, "dump_doclist", "invalid segdir");
+              return;
+            }
+            rc = SQLITE_OK;
+          }
+        }
       }
-      rc = fulltextQuery(v, idxNum-QUERY_FULLTEXT, zQuery, -1, &c->result, &c->q);
-      if( rc!=SQLITE_OK ) return rc;
-      if( c->result.nData!=0 ){
-        dlrInit(&c->reader, DL_DOCIDS, c->result.pData, c->result.nData);
+
+      sqlite3_reset(s);
+    }
+
+    if( rc==SQLITE_OK ){
+      if( doclist.nData>0 ){
+        createDoclistResult(pContext, doclist.pData, doclist.nData);
+      }else{
+        /* TODO(shess): This can happen if the term is not present, or
+        ** if all instances of the term have been deleted and this is
+        ** an all-index dump.  It may be interesting to distinguish
+        ** these cases.
+        */
+        sqlite3_result_text(pContext, "", 0, SQLITE_STATIC);
       }
-      break;
+    }else if( rc==SQLITE_NOMEM ){
+      /* Handle out-of-memory cases specially because if they are
+      ** generated in fts3 code they may not be reflected in the db
+      ** handle.
+      */
+      /* TODO(shess): Handle this more comprehensively.
+      ** sqlite3ErrStr() has what I need, but is internal.
+      */
+      generateError(pContext, "dump_doclist", "out of memory");
+    }else{
+      generateError(pContext, "dump_doclist", NULL);
     }
-  }
 
-  return fulltextNext(pCursor);
+    dataBufferDestroy(&doclist);
+  }
 }
+#endif
 
-/* This is the xEof method of the virtual table.  The SQLite core
-** calls this routine to find out if it has reached the end of
-** a query's results set.
+/*
+** This routine implements the xFindFunction method for the FTS3
+** virtual table.
 */
-static int fulltextEof(sqlite3_vtab_cursor *pCursor){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  return c->eof;
+static int fulltextFindFunction(
+  sqlite3_vtab *pVtab,
+  int nArg,
+  const char *zName,
+  void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
+  void **ppArg
+){
+  if( strcmp(zName,"snippet")==0 ){
+    *pxFunc = snippetFunc;
+    return 1;
+  }else if( strcmp(zName,"offsets")==0 ){
+    *pxFunc = snippetOffsetsFunc;
+    return 1;
+  }else if( strcmp(zName,"optimize")==0 ){
+    *pxFunc = optimizeFunc;
+    return 1;
+#ifdef SQLITE_TEST
+    /* NOTE(shess): These functions are present only for testing
+    ** purposes.  No particular effort is made to optimize their
+    ** execution or how they build their results.
+    */
+  }else if( strcmp(zName,"dump_terms")==0 ){
+    /* fprintf(stderr, "Found dump_terms\n"); */
+    *pxFunc = dumpTermsFunc;
+    return 1;
+  }else if( strcmp(zName,"dump_doclist")==0 ){
+    /* fprintf(stderr, "Found dump_doclist\n"); */
+    *pxFunc = dumpDoclistFunc;
+    return 1;
+#endif
+  }
+  return 0;
 }
 
-/* This is the xColumn method of the virtual table.  The SQLite
-** core calls this method during a query when it needs the value
-** of a column from the virtual table.  This method needs to use
-** one of the sqlite3_result_*() routines to store the requested
-** value back in the pContext.
+/*
+** Rename an fts3 table.
 */
-static int fulltextColumn(sqlite3_vtab_cursor *pCursor,
-                          sqlite3_context *pContext, int idxCol){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  fulltext_vtab *v = cursor_vtab(c);
-
-  if( idxCol<v->nColumn ){
-    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1);
-    sqlite3_result_value(pContext, pVal);
-  }else if( idxCol==v->nColumn ){
-    /* The extra column whose name is the same as the table.
-    ** Return a blob which is a pointer to the cursor
-    */
-    sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT);
-  }else if( idxCol==v->nColumn+1 ){
-    /* The docid column, which is an alias for rowid. */
-    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, 0);
-    sqlite3_result_value(pContext, pVal);
+static int fulltextRename(
+  sqlite3_vtab *pVtab,
+  const char *zName
+){
+  fulltext_vtab *p = (fulltext_vtab *)pVtab;
+  int rc = SQLITE_NOMEM;
+  char *zSql = sqlite3_mprintf(
+    "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';"
+    "ALTER TABLE %Q.'%q_segments' RENAME TO '%q_segments';"
+    "ALTER TABLE %Q.'%q_segdir'   RENAME TO '%q_segdir';"
+    , p->zDb, p->zName, zName 
+    , p->zDb, p->zName, zName 
+    , p->zDb, p->zName, zName
+  );
+  if( zSql ){
+    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
   }
-  return SQLITE_OK;
+  return rc;
 }
 
-/* This is the xRowid method.  The SQLite core calls this routine to
-** retrieve the rowid for the current row of the result set.  fts3
-** exposes %_content.docid as the rowid for the virtual table.  The
-** rowid should be written to *pRowid.
-*/
-static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+static const sqlite3_module fts3Module = {
+  /* iVersion      */ 0,
+  /* xCreate       */ fulltextCreate,
+  /* xConnect      */ fulltextConnect,
+  /* xBestIndex    */ fulltextBestIndex,
+  /* xDisconnect   */ fulltextDisconnect,
+  /* xDestroy      */ fulltextDestroy,
+  /* xOpen         */ fulltextOpen,
+  /* xClose        */ fulltextClose,
+  /* xFilter       */ fulltextFilter,
+  /* xNext         */ fulltextNext,
+  /* xEof          */ fulltextEof,
+  /* xColumn       */ fulltextColumn,
+  /* xRowid        */ fulltextRowid,
+  /* xUpdate       */ fulltextUpdate,
+  /* xBegin        */ fulltextBegin,
+  /* xSync         */ fulltextSync,
+  /* xCommit       */ fulltextCommit,
+  /* xRollback     */ fulltextRollback,
+  /* xFindFunction */ fulltextFindFunction,
+  /* xRename */       fulltextRename,
+};
 
-  *pRowid = sqlite3_column_int64(c->pStmt, 0);
-  return SQLITE_OK;
+static void hashDestroy(void *p){
+  fts3Hash *pHash = (fts3Hash *)p;
+  sqlite3Fts3HashClear(pHash);
+  sqlite3_free(pHash);
 }
 
-/* Add all terms in [zText] to pendingTerms table.  If [iColumn] > 0,
-** we also store positions and offsets in the hash table using that
-** column number.
+/*
+** The fts3 built-in tokenizers - "simple" and "porter" - are implemented
+** in files fts3_tokenizer1.c and fts3_porter.c respectively. The following
+** two forward declarations are for functions declared in these files
+** used to retrieve the respective implementations.
+**
+** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
+** to by the argument to point a the "simple" tokenizer implementation.
+** Function ...PorterTokenizerModule() sets *pModule to point to the
+** porter tokenizer/stemmer implementation.
 */
-static int buildTerms(fulltext_vtab *v, sqlite_int64 iDocid,
-                      const char *zText, int iColumn){
-  sqlite3_tokenizer *pTokenizer = v->pTokenizer;
-  sqlite3_tokenizer_cursor *pCursor;
-  const char *pToken;
-  int nTokenBytes;
-  int iStartOffset, iEndOffset, iPosition;
-  int rc;
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);
 
-  rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
-  if( rc!=SQLITE_OK ) return rc;
+SQLITE_PRIVATE int sqlite3Fts3InitHashTable(sqlite3 *, fts3Hash *, const char *);
 
-  pCursor->pTokenizer = pTokenizer;
-  while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
-                                                   &pToken, &nTokenBytes,
-                                                   &iStartOffset, &iEndOffset,
-                                                   &iPosition)) ){
-    DLCollector *p;
-    int nData;                   /* Size of doclist before our update. */
+/*
+** Initialise the fts3 extension. If this extension is built as part
+** of the sqlite library, then this function is called directly by
+** SQLite. If fts3 is built as a dynamically loadable extension, this
+** function is called by the sqlite3_extension_init() entry point.
+*/
+SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
+  int rc = SQLITE_OK;
+  fts3Hash *pHash = 0;
+  const sqlite3_tokenizer_module *pSimple = 0;
+  const sqlite3_tokenizer_module *pPorter = 0;
+  const sqlite3_tokenizer_module *pIcu = 0;
 
-    /* Positions can't be negative; we use -1 as a terminator
-     * internally.  Token can't be NULL or empty. */
-    if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){
-      rc = SQLITE_ERROR;
-      break;
-    }
+  sqlite3Fts3SimpleTokenizerModule(&pSimple);
+  sqlite3Fts3PorterTokenizerModule(&pPorter);
+#ifdef SQLITE_ENABLE_ICU
+  sqlite3Fts3IcuTokenizerModule(&pIcu);
+#endif
 
-    p = fts3HashFind(&v->pendingTerms, pToken, nTokenBytes);
-    if( p==NULL ){
-      nData = 0;
-      p = dlcNew(iDocid, DL_DEFAULT);
-      fts3HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);
+  /* Allocate and initialise the hash-table used to store tokenizers. */
+  pHash = sqlite3_malloc(sizeof(fts3Hash));
+  if( !pHash ){
+    rc = SQLITE_NOMEM;
+  }else{
+    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
+  }
 
-      /* Overhead for our hash table entry, the key, and the value. */
-      v->nPendingData += sizeof(struct fts3HashElem)+sizeof(*p)+nTokenBytes;
-    }else{
-      nData = p->b.nData;
-      if( p->dlw.iPrevDocid!=iDocid ) dlcNext(p, iDocid);
-    }
-    if( iColumn>=0 ){
-      dlcAddPos(p, iColumn, iPosition, iStartOffset, iEndOffset);
+  /* Load the built-in tokenizers into the hash table */
+  if( rc==SQLITE_OK ){
+    if( sqlite3Fts3HashInsert(pHash, "simple", 7, (void *)pSimple)
+     || sqlite3Fts3HashInsert(pHash, "porter", 7, (void *)pPorter) 
+     || (pIcu && sqlite3Fts3HashInsert(pHash, "icu", 4, (void *)pIcu))
+    ){
+      rc = SQLITE_NOMEM;
     }
-
-    /* Accumulate data added by dlcNew or dlcNext, and dlcAddPos. */
-    v->nPendingData += p->b.nData-nData;
   }
 
-  /* TODO(shess) Check return?  Should this be able to cause errors at
-  ** this point?  Actually, same question about sqlite3_finalize(),
-  ** though one could argue that failure there means that the data is
-  ** not durable.  *ponder*
-  */
-  pTokenizer->pModule->xClose(pCursor);
-  if( SQLITE_DONE == rc ) return SQLITE_OK;
-  return rc;
-}
+#ifdef SQLITE_TEST
+  sqlite3Fts3ExprInitTestInterface(db);
+#endif
 
-/* Add doclists for all terms in [pValues] to pendingTerms table. */
-static int insertTerms(fulltext_vtab *v, sqlite_int64 iDocid,
-                       sqlite3_value **pValues){
-  int i;
-  for(i = 0; i < v->nColumn ; ++i){
-    char *zText = (char*)sqlite3_value_text(pValues[i]);
-    int rc = buildTerms(v, iDocid, zText, i);
-    if( rc!=SQLITE_OK ) return rc;
+  /* Create the virtual table wrapper around the hash-table and overload 
+  ** the two scalar functions. If this is successful, register the
+  ** module with sqlite.
+  */
+  if( SQLITE_OK==rc 
+   && SQLITE_OK==(rc = sqlite3Fts3InitHashTable(db, pHash, "fts3_tokenizer"))
+   && SQLITE_OK==(rc = sqlite3_overload_function(db, "snippet", -1))
+   && SQLITE_OK==(rc = sqlite3_overload_function(db, "offsets", -1))
+   && SQLITE_OK==(rc = sqlite3_overload_function(db, "optimize", -1))
+#ifdef SQLITE_TEST
+   && SQLITE_OK==(rc = sqlite3_overload_function(db, "dump_terms", -1))
+   && SQLITE_OK==(rc = sqlite3_overload_function(db, "dump_doclist", -1))
+#endif
+  ){
+    return sqlite3_create_module_v2(
+        db, "fts3", &fts3Module, (void *)pHash, hashDestroy
+    );
   }
-  return SQLITE_OK;
-}
-
-/* Add empty doclists for all terms in the given row's content to
-** pendingTerms.
-*/
-static int deleteTerms(fulltext_vtab *v, sqlite_int64 iDocid){
-  const char **pValues;
-  int i, rc;
-
-  /* TODO(shess) Should we allow such tables at all? */
-  if( DL_DEFAULT==DL_DOCIDS ) return SQLITE_ERROR;
-
-  rc = content_select(v, iDocid, &pValues);
-  if( rc!=SQLITE_OK ) return rc;
 
-  for(i = 0 ; i < v->nColumn; ++i) {
-    rc = buildTerms(v, iDocid, pValues[i], -1);
-    if( rc!=SQLITE_OK ) break;
+  /* An error has occurred. Delete the hash table and return the error code. */
+  assert( rc!=SQLITE_OK );
+  if( pHash ){
+    sqlite3Fts3HashClear(pHash);
+    sqlite3_free(pHash);
   }
+  return rc;
+}
 
-  freeStringArray(v->nColumn, pValues);
-  return SQLITE_OK;
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db, 
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
+){
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3Fts3Init(db);
 }
+#endif
 
-/* TODO(shess) Refactor the code to remove this forward decl. */
-static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid);
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3.c ************************************************/
+/************** Begin file fts3_expr.c ***************************************/
+/*
+** 2008 Nov 28
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This module contains code that implements a parser for fts3 query strings
+** (the right-hand argument to the MATCH operator). Because the supported 
+** syntax is relatively simple, the whole tokenizer/parser system is
+** hand-coded. The public interface to this module is declared in source
+** code file "fts3_expr.h".
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-/* Insert a row into the %_content table; set *piDocid to be the ID of the
-** new row.  Add doclists for terms to pendingTerms.
+/*
+** By default, this module parses the legacy syntax that has been 
+** traditionally used by fts3. Or, if SQLITE_ENABLE_FTS3_PARENTHESIS
+** is defined, then it uses the new syntax. The differences between
+** the new and the old syntaxes are:
+**
+**  a) The new syntax supports parenthesis. The old does not.
+**
+**  b) The new syntax supports the AND and NOT operators. The old does not.
+**
+**  c) The old syntax supports the "-" token qualifier. This is not 
+**     supported by the new syntax (it is replaced by the NOT operator).
+**
+**  d) When using the old syntax, the OR operator has a greater precedence
+**     than an implicit AND. When using the new, both implicity and explicit
+**     AND operators have a higher precedence than OR.
+**
+** If compiled with SQLITE_TEST defined, then this module exports the
+** symbol "int sqlite3_fts3_enable_parentheses". Setting this variable
+** to zero causes the module to use the old syntax. If it is set to 
+** non-zero the new syntax is activated. This is so both syntaxes can
+** be tested using a single build of testfixture.
 */
-static int index_insert(fulltext_vtab *v, sqlite3_value *pRequestDocid,
-                        sqlite3_value **pValues, sqlite_int64 *piDocid){
-  int rc;
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_fts3_enable_parentheses = 0;
+#else
+# ifdef SQLITE_ENABLE_FTS3_PARENTHESIS 
+#  define sqlite3_fts3_enable_parentheses 1
+# else
+#  define sqlite3_fts3_enable_parentheses 0
+# endif
+#endif
 
-  rc = content_insert(v, pRequestDocid, pValues);  /* execute an SQL INSERT */
-  if( rc!=SQLITE_OK ) return rc;
+/*
+** Default span for NEAR operators.
+*/
+#define SQLITE_FTS3_DEFAULT_NEAR_PARAM 10
 
-  /* docid column is an alias for rowid. */
-  *piDocid = sqlite3_last_insert_rowid(v->db);
-  rc = initPendingTerms(v, *piDocid);
-  if( rc!=SQLITE_OK ) return rc;
 
-  return insertTerms(v, *piDocid, pValues);
-}
+typedef struct ParseContext ParseContext;
+struct ParseContext {
+  sqlite3_tokenizer *pTokenizer;      /* Tokenizer module */
+  const char **azCol;                 /* Array of column names for fts3 table */
+  int nCol;                           /* Number of entries in azCol[] */
+  int iDefaultCol;                    /* Default column to query */
+  sqlite3_context *pCtx;              /* Write error message here */
+  int nNest;                          /* Number of nested brackets */
+};
 
-/* Delete a row from the %_content table; add empty doclists for terms
-** to pendingTerms.
+/*
+** This function is equivalent to the standard isspace() function. 
+**
+** The standard isspace() can be awkward to use safely, because although it
+** is defined to accept an argument of type int, its behaviour when passed
+** an integer that falls outside of the range of the unsigned char type
+** is undefined (and sometimes, "undefined" means segfault). This wrapper
+** is defined to accept an argument of type char, and always returns 0 for
+** any values that fall outside of the range of the unsigned char type (i.e.
+** negative values).
 */
-static int index_delete(fulltext_vtab *v, sqlite_int64 iRow){
-  int rc = initPendingTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = deleteTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
-
-  return content_delete(v, iRow);  /* execute an SQL DELETE */
+static int fts3isspace(char c){
+  return (c&0x80)==0 ? isspace(c) : 0;
 }
 
-/* Update a row in the %_content table; add delete doclists to
-** pendingTerms for old terms not in the new data, add insert doclists
-** to pendingTerms for terms in the new data.
+/*
+** Extract the next token from buffer z (length n) using the tokenizer
+** and other information (column names etc.) in pParse. Create an Fts3Expr
+** structure of type FTSQUERY_PHRASE containing a phrase consisting of this
+** single token and set *ppExpr to point to it. If the end of the buffer is
+** reached before a token is found, set *ppExpr to zero. It is the
+** responsibility of the caller to eventually deallocate the allocated 
+** Fts3Expr structure (if any) by passing it to sqlite3_free().
+**
+** Return SQLITE_OK if successful, or SQLITE_NOMEM if a memory allocation
+** fails.
 */
-static int index_update(fulltext_vtab *v, sqlite_int64 iRow,
-                        sqlite3_value **pValues){
-  int rc = initPendingTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+static int getNextToken(
+  ParseContext *pParse,                   /* fts3 query parse context */
+  int iCol,                               /* Value for Fts3Phrase.iColumn */
+  const char *z, int n,                   /* Input string */
+  Fts3Expr **ppExpr,                      /* OUT: expression */
+  int *pnConsumed                         /* OUT: Number of bytes consumed */
+){
+  sqlite3_tokenizer *pTokenizer = pParse->pTokenizer;
+  sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
+  int rc;
+  sqlite3_tokenizer_cursor *pCursor;
+  Fts3Expr *pRet = 0;
+  int nConsumed = 0;
 
-  /* Generate an empty doclist for each term that previously appeared in this
-   * row. */
-  rc = deleteTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+  rc = pModule->xOpen(pTokenizer, z, n, &pCursor);
+  if( rc==SQLITE_OK ){
+    const char *zToken;
+    int nToken, iStart, iEnd, iPosition;
+    int nByte;                               /* total space to allocate */
 
-  rc = content_update(v, pValues, iRow);  /* execute an SQL UPDATE */
-  if( rc!=SQLITE_OK ) return rc;
+    pCursor->pTokenizer = pTokenizer;
+    rc = pModule->xNext(pCursor, &zToken, &nToken, &iStart, &iEnd, &iPosition);
 
-  /* Now add positions for terms which appear in the updated row. */
-  return insertTerms(v, iRow, pValues);
-}
+    if( rc==SQLITE_OK ){
+      nByte = sizeof(Fts3Expr) + sizeof(Fts3Phrase) + nToken;
+      pRet = (Fts3Expr *)sqlite3_malloc(nByte);
+      if( !pRet ){
+        rc = SQLITE_NOMEM;
+      }else{
+        memset(pRet, 0, nByte);
+        pRet->eType = FTSQUERY_PHRASE;
+        pRet->pPhrase = (Fts3Phrase *)&pRet[1];
+        pRet->pPhrase->nToken = 1;
+        pRet->pPhrase->iColumn = iCol;
+        pRet->pPhrase->aToken[0].n = nToken;
+        pRet->pPhrase->aToken[0].z = (char *)&pRet->pPhrase[1];
+        memcpy(pRet->pPhrase->aToken[0].z, zToken, nToken);
+
+        if( iEnd<n && z[iEnd]=='*' ){
+          pRet->pPhrase->aToken[0].isPrefix = 1;
+          iEnd++;
+        }
+        if( !sqlite3_fts3_enable_parentheses && iStart>0 && z[iStart-1]=='-' ){
+          pRet->pPhrase->isNot = 1;
+        }
+      }
+      nConsumed = iEnd;
+    }
 
-/*******************************************************************/
-/* InteriorWriter is used to collect terms and block references into
-** interior nodes in %_segments.  See commentary at top of file for
-** format.
-*/
+    pModule->xClose(pCursor);
+  }
+  
+  *pnConsumed = nConsumed;
+  *ppExpr = pRet;
+  return rc;
+}
 
-/* How large interior nodes can grow. */
-#define INTERIOR_MAX 2048
 
-/* Minimum number of terms per interior node (except the root). This
-** prevents large terms from making the tree too skinny - must be >0
-** so that the tree always makes progress.  Note that the min tree
-** fanout will be INTERIOR_MIN_TERMS+1.
+/*
+** Enlarge a memory allocation.  If an out-of-memory allocation occurs,
+** then free the old allocation.
 */
-#define INTERIOR_MIN_TERMS 7
-#if INTERIOR_MIN_TERMS<1
-# error INTERIOR_MIN_TERMS must be greater than 0.
-#endif
+void *fts3ReallocOrFree(void *pOrig, int nNew){
+  void *pRet = sqlite3_realloc(pOrig, nNew);
+  if( !pRet ){
+    sqlite3_free(pOrig);
+  }
+  return pRet;
+}
 
-/* ROOT_MAX controls how much data is stored inline in the segment
-** directory.
-*/
-/* TODO(shess) Push ROOT_MAX down to whoever is writing things.  It's
-** only here so that interiorWriterRootInfo() and leafWriterRootInfo()
-** can both see it, but if the caller passed it in, we wouldn't even
-** need a define.
+/*
+** Buffer zInput, length nInput, contains the contents of a quoted string
+** that appeared as part of an fts3 query expression. Neither quote character
+** is included in the buffer. This function attempts to tokenize the entire
+** input buffer and create an Fts3Expr structure of type FTSQUERY_PHRASE 
+** containing the results.
+**
+** If successful, SQLITE_OK is returned and *ppExpr set to point at the
+** allocated Fts3Expr structure. Otherwise, either SQLITE_NOMEM (out of memory
+** error) or SQLITE_ERROR (tokenization error) is returned and *ppExpr set
+** to 0.
 */
-#define ROOT_MAX 1024
-#if ROOT_MAX<VARINT_MAX*2
-# error ROOT_MAX must have enough space for a header.
-#endif
+static int getNextString(
+  ParseContext *pParse,                   /* fts3 query parse context */
+  const char *zInput, int nInput,         /* Input string */
+  Fts3Expr **ppExpr                       /* OUT: expression */
+){
+  sqlite3_tokenizer *pTokenizer = pParse->pTokenizer;
+  sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
+  int rc;
+  Fts3Expr *p = 0;
+  sqlite3_tokenizer_cursor *pCursor = 0;
+  char *zTemp = 0;
+  int nTemp = 0;
 
-/* InteriorBlock stores a linked-list of interior blocks while a lower
-** layer is being constructed.
-*/
-typedef struct InteriorBlock {
-  DataBuffer term;           /* Leftmost term in block's subtree. */
-  DataBuffer data;           /* Accumulated data for the block. */
-  struct InteriorBlock *next;
-} InteriorBlock;
+  rc = pModule->xOpen(pTokenizer, zInput, nInput, &pCursor);
+  if( rc==SQLITE_OK ){
+    int ii;
+    pCursor->pTokenizer = pTokenizer;
+    for(ii=0; rc==SQLITE_OK; ii++){
+      const char *zToken;
+      int nToken, iBegin, iEnd, iPos;
+      rc = pModule->xNext(pCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
+      if( rc==SQLITE_OK ){
+        int nByte = sizeof(Fts3Expr) + sizeof(Fts3Phrase);
+        p = fts3ReallocOrFree(p, nByte+ii*sizeof(struct PhraseToken));
+        zTemp = fts3ReallocOrFree(zTemp, nTemp + nToken);
+        if( !p || !zTemp ){
+          goto no_mem;
+        }
+        if( ii==0 ){
+          memset(p, 0, nByte);
+          p->pPhrase = (Fts3Phrase *)&p[1];
+        }
+        p->pPhrase = (Fts3Phrase *)&p[1];
+        p->pPhrase->nToken = ii+1;
+        p->pPhrase->aToken[ii].n = nToken;
+        memcpy(&zTemp[nTemp], zToken, nToken);
+        nTemp += nToken;
+        if( iEnd<nInput && zInput[iEnd]=='*' ){
+          p->pPhrase->aToken[ii].isPrefix = 1;
+        }else{
+          p->pPhrase->aToken[ii].isPrefix = 0;
+        }
+      }
+    }
 
-static InteriorBlock *interiorBlockNew(int iHeight, sqlite_int64 iChildBlock,
-                                       const char *pTerm, int nTerm){
-  InteriorBlock *block = sqlite3_malloc(sizeof(InteriorBlock));
-  char c[VARINT_MAX+VARINT_MAX];
-  int n;
+    pModule->xClose(pCursor);
+    pCursor = 0;
+  }
 
-  if( block ){
-    memset(block, 0, sizeof(*block));
-    dataBufferInit(&block->term, 0);
-    dataBufferReplace(&block->term, pTerm, nTerm);
+  if( rc==SQLITE_DONE ){
+    int jj;
+    char *zNew;
+    int nNew = 0;
+    int nByte = sizeof(Fts3Expr) + sizeof(Fts3Phrase);
+    nByte += (p?(p->pPhrase->nToken-1):0) * sizeof(struct PhraseToken);
+    p = fts3ReallocOrFree(p, nByte + nTemp);
+    if( !p ){
+      goto no_mem;
+    }
+    if( zTemp ){
+      zNew = &(((char *)p)[nByte]);
+      memcpy(zNew, zTemp, nTemp);
+    }else{
+      memset(p, 0, nByte+nTemp);
+    }
+    p->pPhrase = (Fts3Phrase *)&p[1];
+    for(jj=0; jj<p->pPhrase->nToken; jj++){
+      p->pPhrase->aToken[jj].z = &zNew[nNew];
+      nNew += p->pPhrase->aToken[jj].n;
+    }
+    sqlite3_free(zTemp);
+    p->eType = FTSQUERY_PHRASE;
+    p->pPhrase->iColumn = pParse->iDefaultCol;
+    rc = SQLITE_OK;
+  }
 
-    n = fts3PutVarint(c, iHeight);
-    n += fts3PutVarint(c+n, iChildBlock);
-    dataBufferInit(&block->data, INTERIOR_MAX);
-    dataBufferReplace(&block->data, c, n);
+  *ppExpr = p;
+  return rc;
+no_mem:
+
+  if( pCursor ){
+    pModule->xClose(pCursor);
   }
-  return block;
+  sqlite3_free(zTemp);
+  sqlite3_free(p);
+  *ppExpr = 0;
+  return SQLITE_NOMEM;
 }
 
-#ifndef NDEBUG
-/* Verify that the data is readable as an interior node. */
-static void interiorBlockValidate(InteriorBlock *pBlock){
-  const char *pData = pBlock->data.pData;
-  int nData = pBlock->data.nData;
-  int n, iDummy;
-  sqlite_int64 iBlockid;
-
-  assert( nData>0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
+/*
+** Function getNextNode(), which is called by fts3ExprParse(), may itself
+** call fts3ExprParse(). So this forward declaration is required.
+*/
+static int fts3ExprParse(ParseContext *, const char *, int, Fts3Expr **, int *);
 
-  /* Must lead with height of node as a varint(n), n>0 */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( n>0 );
-  assert( iDummy>0 );
-  assert( n<nData );
-  pData += n;
-  nData -= n;
+/*
+** The output variable *ppExpr is populated with an allocated Fts3Expr 
+** structure, or set to 0 if the end of the input buffer is reached.
+**
+** Returns an SQLite error code. SQLITE_OK if everything works, SQLITE_NOMEM
+** if a malloc failure occurs, or SQLITE_ERROR if a parse error is encountered.
+** If SQLITE_ERROR is returned, pContext is populated with an error message.
+*/
+static int getNextNode(
+  ParseContext *pParse,                   /* fts3 query parse context */
+  const char *z, int n,                   /* Input string */
+  Fts3Expr **ppExpr,                      /* OUT: expression */
+  int *pnConsumed                         /* OUT: Number of bytes consumed */
+){
+  static const struct Fts3Keyword {
+    char z[4];                            /* Keyword text */
+    unsigned char n;                      /* Length of the keyword */
+    unsigned char parenOnly;              /* Only valid in paren mode */
+    unsigned char eType;                  /* Keyword code */
+  } aKeyword[] = {
+    { "OR" ,  2, 0, FTSQUERY_OR   },
+    { "AND",  3, 1, FTSQUERY_AND  },
+    { "NOT",  3, 1, FTSQUERY_NOT  },
+    { "NEAR", 4, 0, FTSQUERY_NEAR }
+  };
+  int ii;
+  int iCol;
+  int iColLen;
+  int rc;
+  Fts3Expr *pRet = 0;
 
-  /* Must contain iBlockid. */
-  n = fts3GetVarint(pData, &iBlockid);
-  assert( n>0 );
-  assert( n<=nData );
-  pData += n;
-  nData -= n;
+  const char *zInput = z;
+  int nInput = n;
 
-  /* Zero or more terms of positive length */
-  if( nData!=0 ){
-    /* First term is not delta-encoded. */
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0);
-    assert( n+iDummy<=nData );
-    pData += n+iDummy;
-    nData -= n+iDummy;
+  /* Skip over any whitespace before checking for a keyword, an open or
+  ** close bracket, or a quoted string. 
+  */
+  while( nInput>0 && fts3isspace(*zInput) ){
+    nInput--;
+    zInput++;
+  }
+  if( nInput==0 ){
+    return SQLITE_DONE;
+  }
 
-    /* Following terms delta-encoded. */
-    while( nData!=0 ){
-      /* Length of shared prefix. */
-      n = fts3GetVarint32(pData, &iDummy);
-      assert( n>0 );
-      assert( iDummy>=0 );
-      assert( n<nData );
-      pData += n;
-      nData -= n;
+  /* See if we are dealing with a keyword. */
+  for(ii=0; ii<(int)(sizeof(aKeyword)/sizeof(struct Fts3Keyword)); ii++){
+    const struct Fts3Keyword *pKey = &aKeyword[ii];
 
-      /* Length and data of distinct suffix. */
-      n = fts3GetVarint32(pData, &iDummy);
-      assert( n>0 );
-      assert( iDummy>0 );
-      assert( n+iDummy>0);
-      assert( n+iDummy<=nData );
-      pData += n+iDummy;
-      nData -= n+iDummy;
+    if( (pKey->parenOnly & ~sqlite3_fts3_enable_parentheses)!=0 ){
+      continue;
     }
-  }
-}
-#define ASSERT_VALID_INTERIOR_BLOCK(x) interiorBlockValidate(x)
-#else
-#define ASSERT_VALID_INTERIOR_BLOCK(x) assert( 1 )
-#endif
-
-typedef struct InteriorWriter {
-  int iHeight;                   /* from 0 at leaves. */
-  InteriorBlock *first, *last;
-  struct InteriorWriter *parentWriter;
 
-  DataBuffer term;               /* Last term written to block "last". */
-  sqlite_int64 iOpeningChildBlock; /* First child block in block "last". */
-#ifndef NDEBUG
-  sqlite_int64 iLastChildBlock;  /* for consistency checks. */
-#endif
-} InteriorWriter;
+    if( nInput>=pKey->n && 0==memcmp(zInput, pKey->z, pKey->n) ){
+      int nNear = SQLITE_FTS3_DEFAULT_NEAR_PARAM;
+      int nKey = pKey->n;
+      char cNext;
 
-/* Initialize an interior node where pTerm[nTerm] marks the leftmost
-** term in the tree.  iChildBlock is the leftmost child block at the
-** next level down the tree.
-*/
-static void interiorWriterInit(int iHeight, const char *pTerm, int nTerm,
-                               sqlite_int64 iChildBlock,
-                               InteriorWriter *pWriter){
-  InteriorBlock *block;
-  assert( iHeight>0 );
-  CLEAR(pWriter);
+      /* If this is a "NEAR" keyword, check for an explicit nearness. */
+      if( pKey->eType==FTSQUERY_NEAR ){
+        assert( nKey==4 );
+        if( zInput[4]=='/' && zInput[5]>='0' && zInput[5]<='9' ){
+          nNear = 0;
+          for(nKey=5; zInput[nKey]>='0' && zInput[nKey]<='9'; nKey++){
+            nNear = nNear * 10 + (zInput[nKey] - '0');
+          }
+        }
+      }
 
-  pWriter->iHeight = iHeight;
-  pWriter->iOpeningChildBlock = iChildBlock;
-#ifndef NDEBUG
-  pWriter->iLastChildBlock = iChildBlock;
-#endif
-  block = interiorBlockNew(iHeight, iChildBlock, pTerm, nTerm);
-  pWriter->last = pWriter->first = block;
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
-  dataBufferInit(&pWriter->term, 0);
-}
+      /* At this point this is probably a keyword. But for that to be true,
+      ** the next byte must contain either whitespace, an open or close
+      ** parenthesis, a quote character, or EOF. 
+      */
+      cNext = zInput[nKey];
+      if( fts3isspace(cNext) 
+       || cNext=='"' || cNext=='(' || cNext==')' || cNext==0
+      ){
+        pRet = (Fts3Expr *)sqlite3_malloc(sizeof(Fts3Expr));
+        memset(pRet, 0, sizeof(Fts3Expr));
+        pRet->eType = pKey->eType;
+        pRet->nNear = nNear;
+        *ppExpr = pRet;
+        *pnConsumed = (zInput - z) + nKey;
+        return SQLITE_OK;
+      }
 
-/* Append the child node rooted at iChildBlock to the interior node,
-** with pTerm[nTerm] as the leftmost term in iChildBlock's subtree.
-*/
-static void interiorWriterAppend(InteriorWriter *pWriter,
-                                 const char *pTerm, int nTerm,
-                                 sqlite_int64 iChildBlock){
-  char c[VARINT_MAX+VARINT_MAX];
-  int n, nPrefix = 0;
+      /* Turns out that wasn't a keyword after all. This happens if the
+      ** user has supplied a token such as "ORacle". Continue.
+      */
+    }
+  }
 
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+  /* Check for an open bracket. */
+  if( sqlite3_fts3_enable_parentheses ){
+    if( *zInput=='(' ){
+      int nConsumed;
+      int rc;
+      pParse->nNest++;
+      rc = fts3ExprParse(pParse, &zInput[1], nInput-1, ppExpr, &nConsumed);
+      if( rc==SQLITE_OK && !*ppExpr ){
+        rc = SQLITE_DONE;
+      }
+      *pnConsumed = (zInput - z) + 1 + nConsumed;
+      return rc;
+    }
+  
+    /* Check for a close bracket. */
+    if( *zInput==')' ){
+      pParse->nNest--;
+      *pnConsumed = (zInput - z) + 1;
+      return SQLITE_DONE;
+    }
+  }
 
-  /* The first term written into an interior node is actually
-  ** associated with the second child added (the first child was added
-  ** in interiorWriterInit, or in the if clause at the bottom of this
-  ** function).  That term gets encoded straight up, with nPrefix left
-  ** at 0.
+  /* See if we are dealing with a quoted phrase. If this is the case, then
+  ** search for the closing quote and pass the whole string to getNextString()
+  ** for processing. This is easy to do, as fts3 has no syntax for escaping
+  ** a quote character embedded in a string.
   */
-  if( pWriter->term.nData==0 ){
-    n = fts3PutVarint(c, nTerm);
-  }else{
-    while( nPrefix<pWriter->term.nData &&
-           pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
-      nPrefix++;
+  if( *zInput=='"' ){
+    for(ii=1; ii<nInput && zInput[ii]!='"'; ii++);
+    *pnConsumed = (zInput - z) + ii + 1;
+    if( ii==nInput ){
+      return SQLITE_ERROR;
     }
-
-    n = fts3PutVarint(c, nPrefix);
-    n += fts3PutVarint(c+n, nTerm-nPrefix);
+    return getNextString(pParse, &zInput[1], ii-1, ppExpr);
   }
 
-#ifndef NDEBUG
-  pWriter->iLastChildBlock++;
-#endif
-  assert( pWriter->iLastChildBlock==iChildBlock );
 
-  /* Overflow to a new block if the new term makes the current block
-  ** too big, and the current block already has enough terms.
-  */
-  if( pWriter->last->data.nData+n+nTerm-nPrefix>INTERIOR_MAX &&
-      iChildBlock-pWriter->iOpeningChildBlock>INTERIOR_MIN_TERMS ){
-    pWriter->last->next = interiorBlockNew(pWriter->iHeight, iChildBlock,
-                                           pTerm, nTerm);
-    pWriter->last = pWriter->last->next;
-    pWriter->iOpeningChildBlock = iChildBlock;
-    dataBufferReset(&pWriter->term);
-  }else{
-    dataBufferAppend2(&pWriter->last->data, c, n,
-                      pTerm+nPrefix, nTerm-nPrefix);
-    dataBufferReplace(&pWriter->term, pTerm, nTerm);
+  /* If control flows to this point, this must be a regular token, or 
+  ** the end of the input. Read a regular token using the sqlite3_tokenizer
+  ** interface. Before doing so, figure out if there is an explicit
+  ** column specifier for the token. 
+  **
+  ** TODO: Strangely, it is not possible to associate a column specifier
+  ** with a quoted phrase, only with a single token. Not sure if this was
+  ** an implementation artifact or an intentional decision when fts3 was
+  ** first implemented. Whichever it was, this module duplicates the 
+  ** limitation.
+  */
+  iCol = pParse->iDefaultCol;
+  iColLen = 0;
+  for(ii=0; ii<pParse->nCol; ii++){
+    const char *zStr = pParse->azCol[ii];
+    int nStr = strlen(zStr);
+    if( nInput>nStr && zInput[nStr]==':' 
+     && sqlite3_strnicmp(zStr, zInput, nStr)==0 
+    ){
+      iCol = ii;
+      iColLen = ((zInput - z) + nStr + 1);
+      break;
+    }
   }
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+  rc = getNextToken(pParse, iCol, &z[iColLen], n-iColLen, ppExpr, pnConsumed);
+  *pnConsumed += iColLen;
+  return rc;
 }
 
-/* Free the space used by pWriter, including the linked-list of
-** InteriorBlocks, and parentWriter, if present.
+/*
+** The argument is an Fts3Expr structure for a binary operator (any type
+** except an FTSQUERY_PHRASE). Return an integer value representing the
+** precedence of the operator. Lower values have a higher precedence (i.e.
+** group more tightly). For example, in the C language, the == operator
+** groups more tightly than ||, and would therefore have a higher precedence.
+**
+** When using the new fts3 query syntax (when SQLITE_ENABLE_FTS3_PARENTHESIS
+** is defined), the order of the operators in precedence from highest to
+** lowest is:
+**
+**   NEAR
+**   NOT
+**   AND (including implicit ANDs)
+**   OR
+**
+** Note that when using the old query syntax, the OR operator has a higher
+** precedence than the AND operator.
 */
-static int interiorWriterDestroy(InteriorWriter *pWriter){
-  InteriorBlock *block = pWriter->first;
-
-  while( block!=NULL ){
-    InteriorBlock *b = block;
-    block = block->next;
-    dataBufferDestroy(&b->term);
-    dataBufferDestroy(&b->data);
-    sqlite3_free(b);
-  }
-  if( pWriter->parentWriter!=NULL ){
-    interiorWriterDestroy(pWriter->parentWriter);
-    sqlite3_free(pWriter->parentWriter);
+static int opPrecedence(Fts3Expr *p){
+  assert( p->eType!=FTSQUERY_PHRASE );
+  if( sqlite3_fts3_enable_parentheses ){
+    return p->eType;
+  }else if( p->eType==FTSQUERY_NEAR ){
+    return 1;
+  }else if( p->eType==FTSQUERY_OR ){
+    return 2;
   }
-  dataBufferDestroy(&pWriter->term);
-  SCRAMBLE(pWriter);
-  return SQLITE_OK;
+  assert( p->eType==FTSQUERY_AND );
+  return 3;
 }
 
-/* If pWriter can fit entirely in ROOT_MAX, return it as the root info
-** directly, leaving *piEndBlockid unchanged.  Otherwise, flush
-** pWriter to %_segments, building a new layer of interior nodes, and
-** recursively ask for their root into.
+/*
+** Argument ppHead contains a pointer to the current head of a query 
+** expression tree being parsed. pPrev is the expression node most recently
+** inserted into the tree. This function adds pNew, which is always a binary
+** operator node, into the expression tree based on the relative precedence
+** of pNew and the existing nodes of the tree. This may result in the head
+** of the tree changing, in which case *ppHead is set to the new root node.
 */
-static int interiorWriterRootInfo(fulltext_vtab *v, InteriorWriter *pWriter,
-                                  char **ppRootInfo, int *pnRootInfo,
-                                  sqlite_int64 *piEndBlockid){
-  InteriorBlock *block = pWriter->first;
-  sqlite_int64 iBlockid = 0;
-  int rc;
-
-  /* If we can fit the segment inline */
-  if( block==pWriter->last && block->data.nData<ROOT_MAX ){
-    *ppRootInfo = block->data.pData;
-    *pnRootInfo = block->data.nData;
-    return SQLITE_OK;
+static void insertBinaryOperator(
+  Fts3Expr **ppHead,       /* Pointer to the root node of a tree */
+  Fts3Expr *pPrev,         /* Node most recently inserted into the tree */
+  Fts3Expr *pNew           /* New binary node to insert into expression tree */
+){
+  Fts3Expr *pSplit = pPrev;
+  while( pSplit->pParent && opPrecedence(pSplit->pParent)<=opPrecedence(pNew) ){
+    pSplit = pSplit->pParent;
   }
 
-  /* Flush the first block to %_segments, and create a new level of
-  ** interior node.
-  */
-  ASSERT_VALID_INTERIOR_BLOCK(block);
-  rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-  *piEndBlockid = iBlockid;
-
-  pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
-  interiorWriterInit(pWriter->iHeight+1,
-                     block->term.pData, block->term.nData,
-                     iBlockid, pWriter->parentWriter);
-
-  /* Flush additional blocks and append to the higher interior
-  ** node.
-  */
-  for(block=block->next; block!=NULL; block=block->next){
-    ASSERT_VALID_INTERIOR_BLOCK(block);
-    rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
-    if( rc!=SQLITE_OK ) return rc;
-    *piEndBlockid = iBlockid;
-
-    interiorWriterAppend(pWriter->parentWriter,
-                         block->term.pData, block->term.nData, iBlockid);
+  if( pSplit->pParent ){
+    assert( pSplit->pParent->pRight==pSplit );
+    pSplit->pParent->pRight = pNew;
+    pNew->pParent = pSplit->pParent;
+  }else{
+    *ppHead = pNew;
   }
-
-  /* Parent node gets the chance to be the root. */
-  return interiorWriterRootInfo(v, pWriter->parentWriter,
-                                ppRootInfo, pnRootInfo, piEndBlockid);
+  pNew->pLeft = pSplit;
+  pSplit->pParent = pNew;
 }
 
-/****************************************************************/
-/* InteriorReader is used to read off the data from an interior node
-** (see comment at top of file for the format).
+/*
+** Parse the fts3 query expression found in buffer z, length n. This function
+** returns either when the end of the buffer is reached or an unmatched 
+** closing bracket - ')' - is encountered.
+**
+** If successful, SQLITE_OK is returned, *ppExpr is set to point to the
+** parsed form of the expression and *pnConsumed is set to the number of
+** bytes read from buffer z. Otherwise, *ppExpr is set to 0 and SQLITE_NOMEM
+** (out of memory error) or SQLITE_ERROR (parse error) is returned.
 */
-typedef struct InteriorReader {
-  const char *pData;
-  int nData;
-
-  DataBuffer term;          /* previous term, for decoding term delta. */
-
-  sqlite_int64 iBlockid;
-} InteriorReader;
+static int fts3ExprParse(
+  ParseContext *pParse,                   /* fts3 query parse context */
+  const char *z, int n,                   /* Text of MATCH query */
+  Fts3Expr **ppExpr,                      /* OUT: Parsed query structure */
+  int *pnConsumed                         /* OUT: Number of bytes consumed */
+){
+  Fts3Expr *pRet = 0;
+  Fts3Expr *pPrev = 0;
+  Fts3Expr *pNotBranch = 0;               /* Only used in legacy parse mode */
+  int nIn = n;
+  const char *zIn = z;
+  int rc = SQLITE_OK;
+  int isRequirePhrase = 1;
 
-static void interiorReaderDestroy(InteriorReader *pReader){
-  dataBufferDestroy(&pReader->term);
-  SCRAMBLE(pReader);
-}
+  while( rc==SQLITE_OK ){
+    Fts3Expr *p = 0;
+    int nByte = 0;
+    rc = getNextNode(pParse, zIn, nIn, &p, &nByte);
+    if( rc==SQLITE_OK ){
+      int isPhrase;
 
-/* TODO(shess) The assertions are great, but what if we're in NDEBUG
-** and the blob is empty or otherwise contains suspect data?
-*/
-static void interiorReaderInit(const char *pData, int nData,
-                               InteriorReader *pReader){
-  int n, nTerm;
+      if( !sqlite3_fts3_enable_parentheses 
+       && p->eType==FTSQUERY_PHRASE && p->pPhrase->isNot 
+      ){
+        /* Create an implicit NOT operator. */
+        Fts3Expr *pNot = sqlite3_malloc(sizeof(Fts3Expr));
+        if( !pNot ){
+          sqlite3Fts3ExprFree(p);
+          rc = SQLITE_NOMEM;
+          goto exprparse_out;
+        }
+        memset(pNot, 0, sizeof(Fts3Expr));
+        pNot->eType = FTSQUERY_NOT;
+        pNot->pRight = p;
+        if( pNotBranch ){
+          pNot->pLeft = pNotBranch;
+        }
+        pNotBranch = pNot;
+        p = pPrev;
+      }else{
+        int eType = p->eType;
+        assert( eType!=FTSQUERY_PHRASE || !p->pPhrase->isNot );
+        isPhrase = (eType==FTSQUERY_PHRASE || p->pLeft);
+
+        /* The isRequirePhrase variable is set to true if a phrase or
+        ** an expression contained in parenthesis is required. If a
+        ** binary operator (AND, OR, NOT or NEAR) is encounted when
+        ** isRequirePhrase is set, this is a syntax error.
+        */
+        if( !isPhrase && isRequirePhrase ){
+          sqlite3Fts3ExprFree(p);
+          rc = SQLITE_ERROR;
+          goto exprparse_out;
+        }
+  
+        if( isPhrase && !isRequirePhrase ){
+          /* Insert an implicit AND operator. */
+          Fts3Expr *pAnd;
+          assert( pRet && pPrev );
+          pAnd = sqlite3_malloc(sizeof(Fts3Expr));
+          if( !pAnd ){
+            sqlite3Fts3ExprFree(p);
+            rc = SQLITE_NOMEM;
+            goto exprparse_out;
+          }
+          memset(pAnd, 0, sizeof(Fts3Expr));
+          pAnd->eType = FTSQUERY_AND;
+          insertBinaryOperator(&pRet, pPrev, pAnd);
+          pPrev = pAnd;
+        }
 
-  /* Require at least the leading flag byte */
-  assert( nData>0 );
-  assert( pData[0]!='\0' );
+        /* This test catches attempts to make either operand of a NEAR
+        ** operator something other than a phrase. For example, either of
+        ** the following:
+        **
+        **    (bracketed expression) NEAR phrase
+        **    phrase NEAR (bracketed expression)
+        **
+        ** Return an error in either case.
+        */
+        if( pPrev && (
+            (eType==FTSQUERY_NEAR && !isPhrase && pPrev->eType!=FTSQUERY_PHRASE)
+         || (eType!=FTSQUERY_PHRASE && isPhrase && pPrev->eType==FTSQUERY_NEAR)
+        )){
+          sqlite3Fts3ExprFree(p);
+          rc = SQLITE_ERROR;
+          goto exprparse_out;
+        }
+  
+        if( isPhrase ){
+          if( pRet ){
+            assert( pPrev && pPrev->pLeft && pPrev->pRight==0 );
+            pPrev->pRight = p;
+            p->pParent = pPrev;
+          }else{
+            pRet = p;
+          }
+        }else{
+          insertBinaryOperator(&pRet, pPrev, p);
+        }
+        isRequirePhrase = !isPhrase;
+      }
+      assert( nByte>0 );
+    }
+    assert( rc!=SQLITE_OK || (nByte>0 && nByte<=nIn) );
+    nIn -= nByte;
+    zIn += nByte;
+    pPrev = p;
+  }
 
-  CLEAR(pReader);
+  if( rc==SQLITE_DONE && pRet && isRequirePhrase ){
+    rc = SQLITE_ERROR;
+  }
 
-  /* Decode the base blockid, and set the cursor to the first term. */
-  n = fts3GetVarint(pData+1, &pReader->iBlockid);
-  assert( 1+n<=nData );
-  pReader->pData = pData+1+n;
-  pReader->nData = nData-(1+n);
+  if( rc==SQLITE_DONE ){
+    rc = SQLITE_OK;
+    if( !sqlite3_fts3_enable_parentheses && pNotBranch ){
+      if( !pRet ){
+        rc = SQLITE_ERROR;
+      }else{
+        Fts3Expr *pIter = pNotBranch;
+        while( pIter->pLeft ){
+          pIter = pIter->pLeft;
+        }
+        pIter->pLeft = pRet;
+        pRet = pNotBranch;
+      }
+    }
+  }
+  *pnConsumed = n - nIn;
 
-  /* A single-child interior node (such as when a leaf node was too
-  ** large for the segment directory) won't have any terms.
-  ** Otherwise, decode the first term.
-  */
-  if( pReader->nData==0 ){
-    dataBufferInit(&pReader->term, 0);
-  }else{
-    n = fts3GetVarint32(pReader->pData, &nTerm);
-    dataBufferInit(&pReader->term, nTerm);
-    dataBufferReplace(&pReader->term, pReader->pData+n, nTerm);
-    assert( n+nTerm<=pReader->nData );
-    pReader->pData += n+nTerm;
-    pReader->nData -= n+nTerm;
+exprparse_out:
+  if( rc!=SQLITE_OK ){
+    sqlite3Fts3ExprFree(pRet);
+    sqlite3Fts3ExprFree(pNotBranch);
+    pRet = 0;
   }
+  *ppExpr = pRet;
+  return rc;
 }
 
-static int interiorReaderAtEnd(InteriorReader *pReader){
-  return pReader->term.nData==0;
-}
+/*
+** Parameters z and n contain a pointer to and length of a buffer containing
+** an fts3 query expression, respectively. This function attempts to parse the
+** query expression and create a tree of Fts3Expr structures representing the
+** parsed expression. If successful, *ppExpr is set to point to the head
+** of the parsed expression tree and SQLITE_OK is returned. If an error
+** occurs, either SQLITE_NOMEM (out-of-memory error) or SQLITE_ERROR (parse
+** error) is returned and *ppExpr is set to 0.
+**
+** If parameter n is a negative number, then z is assumed to point to a
+** nul-terminated string and the length is determined using strlen().
+**
+** The first parameter, pTokenizer, is passed the fts3 tokenizer module to
+** use to normalize query tokens while parsing the expression. The azCol[]
+** array, which is assumed to contain nCol entries, should contain the names
+** of each column in the target fts3 table, in order from left to right. 
+** Column names must be nul-terminated strings.
+**
+** The iDefaultCol parameter should be passed the index of the table column
+** that appears on the left-hand-side of the MATCH operator (the default
+** column to match against for tokens for which a column name is not explicitly
+** specified as part of the query string), or -1 if tokens may by default
+** match any table column.
+*/
+SQLITE_PRIVATE int sqlite3Fts3ExprParse(
+  sqlite3_tokenizer *pTokenizer,      /* Tokenizer module */
+  char **azCol,                       /* Array of column names for fts3 table */
+  int nCol,                           /* Number of entries in azCol[] */
+  int iDefaultCol,                    /* Default column to query */
+  const char *z, int n,               /* Text of MATCH query */
+  Fts3Expr **ppExpr                   /* OUT: Parsed query structure */
+){
+  int nParsed;
+  int rc;
+  ParseContext sParse;
+  sParse.pTokenizer = pTokenizer;
+  sParse.azCol = (const char **)azCol;
+  sParse.nCol = nCol;
+  sParse.iDefaultCol = iDefaultCol;
+  sParse.nNest = 0;
+  if( z==0 ){
+    *ppExpr = 0;
+    return SQLITE_OK;
+  }
+  if( n<0 ){
+    n = strlen(z);
+  }
+  rc = fts3ExprParse(&sParse, z, n, ppExpr, &nParsed);
 
-static sqlite_int64 interiorReaderCurrentBlockid(InteriorReader *pReader){
-  return pReader->iBlockid;
-}
+  /* Check for mismatched parenthesis */
+  if( rc==SQLITE_OK && sParse.nNest ){
+    rc = SQLITE_ERROR;
+    sqlite3Fts3ExprFree(*ppExpr);
+    *ppExpr = 0;
+  }
 
-static int interiorReaderTermBytes(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
-  return pReader->term.nData;
+  return rc;
 }
-static const char *interiorReaderTerm(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
-  return pReader->term.pData;
+
+/*
+** Free a parsed fts3 query expression allocated by sqlite3Fts3ExprParse().
+*/
+SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *p){
+  if( p ){
+    sqlite3Fts3ExprFree(p->pLeft);
+    sqlite3Fts3ExprFree(p->pRight);
+    sqlite3_free(p);
+  }
 }
 
-/* Step forward to the next term in the node. */
-static void interiorReaderStep(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
+/****************************************************************************
+*****************************************************************************
+** Everything after this point is just test code.
+*/
 
-  /* If the last term has been read, signal eof, else construct the
-  ** next term.
-  */
-  if( pReader->nData==0 ){
-    dataBufferReset(&pReader->term);
-  }else{
-    int n, nPrefix, nSuffix;
+#ifdef SQLITE_TEST
 
-    n = fts3GetVarint32(pReader->pData, &nPrefix);
-    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
 
-    /* Truncate the current term and append suffix data. */
-    pReader->term.nData = nPrefix;
-    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
+/*
+** Function to query the hash-table of tokenizers (see README.tokenizers).
+*/
+static int queryTestTokenizer(
+  sqlite3 *db, 
+  const char *zName,  
+  const sqlite3_tokenizer_module **pp
+){
+  int rc;
+  sqlite3_stmt *pStmt;
+  const char zSql[] = "SELECT fts3_tokenizer(?)";
 
-    assert( n+nSuffix<=pReader->nData );
-    pReader->pData += n+nSuffix;
-    pReader->nData -= n+nSuffix;
+  *pp = 0;
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
-  pReader->iBlockid++;
+
+  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
+  if( SQLITE_ROW==sqlite3_step(pStmt) ){
+    if( sqlite3_column_type(pStmt, 0)==SQLITE_BLOB ){
+      memcpy(pp, sqlite3_column_blob(pStmt, 0), sizeof(*pp));
+    }
+  }
+
+  return sqlite3_finalize(pStmt);
 }
 
-/* Compare the current term to pTerm[nTerm], returning strcmp-style
-** results.  If isPrefix, equality means equal through nTerm bytes.
+/*
+** This function is part of the test interface for the query parser. It
+** writes a text representation of the query expression pExpr into the
+** buffer pointed to by argument zBuf. It is assumed that zBuf is large 
+** enough to store the required text representation.
 */
-static int interiorReaderTermCmp(InteriorReader *pReader,
-                                 const char *pTerm, int nTerm, int isPrefix){
-  const char *pReaderTerm = interiorReaderTerm(pReader);
-  int nReaderTerm = interiorReaderTermBytes(pReader);
-  int c, n = nReaderTerm<nTerm ? nReaderTerm : nTerm;
+static void exprToString(Fts3Expr *pExpr, char *zBuf){
+  switch( pExpr->eType ){
+    case FTSQUERY_PHRASE: {
+      Fts3Phrase *pPhrase = pExpr->pPhrase;
+      int i;
+      zBuf += sprintf(zBuf, "PHRASE %d %d", pPhrase->iColumn, pPhrase->isNot);
+      for(i=0; i<pPhrase->nToken; i++){
+        zBuf += sprintf(zBuf," %.*s",pPhrase->aToken[i].n,pPhrase->aToken[i].z);
+        zBuf += sprintf(zBuf,"%s", (pPhrase->aToken[i].isPrefix?"+":""));
+      }
+      return;
+    }
 
-  if( n==0 ){
-    if( nReaderTerm>0 ) return -1;
-    if( nTerm>0 ) return 1;
-    return 0;
+    case FTSQUERY_NEAR:
+      zBuf += sprintf(zBuf, "NEAR/%d ", pExpr->nNear);
+      break;
+    case FTSQUERY_NOT:
+      zBuf += sprintf(zBuf, "NOT ");
+      break;
+    case FTSQUERY_AND:
+      zBuf += sprintf(zBuf, "AND ");
+      break;
+    case FTSQUERY_OR:
+      zBuf += sprintf(zBuf, "OR ");
+      break;
   }
 
-  c = memcmp(pReaderTerm, pTerm, n);
-  if( c!=0 ) return c;
-  if( isPrefix && n==nTerm ) return 0;
-  return nReaderTerm - nTerm;
+  zBuf += sprintf(zBuf, "{");
+  exprToString(pExpr->pLeft, zBuf);
+  zBuf += strlen(zBuf);
+  zBuf += sprintf(zBuf, "} ");
+
+  zBuf += sprintf(zBuf, "{");
+  exprToString(pExpr->pRight, zBuf);
+  zBuf += strlen(zBuf);
+  zBuf += sprintf(zBuf, "}");
 }
 
-/****************************************************************/
-/* LeafWriter is used to collect terms and associated doclist data
-** into leaf blocks in %_segments (see top of file for format info).
-** Expected usage is:
+/*
+** This is the implementation of a scalar SQL function used to test the 
+** expression parser. It should be called as follows:
 **
-** LeafWriter writer;
-** leafWriterInit(0, 0, &writer);
-** while( sorted_terms_left_to_process ){
-**   // data is doclist data for that term.
-**   rc = leafWriterStep(v, &writer, pTerm, nTerm, pData, nData);
-**   if( rc!=SQLITE_OK ) goto err;
-** }
-** rc = leafWriterFinalize(v, &writer);
-**err:
-** leafWriterDestroy(&writer);
-** return rc;
+**   fts3_exprtest(<tokenizer>, <expr>, <column 1>, ...);
 **
-** leafWriterStep() may write a collected leaf out to %_segments.
-** leafWriterFinalize() finishes writing any buffered data and stores
-** a root node in %_segdir.  leafWriterDestroy() frees all buffers and
-** InteriorWriters allocated as part of writing this segment.
+** The first argument, <tokenizer>, is the name of the fts3 tokenizer used
+** to parse the query expression (see README.tokenizers). The second argument
+** is the query expression to parse. Each subsequent argument is the name
+** of a column of the fts3 table that the query expression may refer to.
+** For example:
 **
-** TODO(shess) Document leafWriterStepMerge().
+**   SELECT fts3_exprtest('simple', 'Bill col2:Bloggs', 'col1', 'col2');
 */
+static void fts3ExprTest(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  sqlite3_tokenizer_module const *pModule = 0;
+  sqlite3_tokenizer *pTokenizer = 0;
+  int rc;
+  char **azCol = 0;
+  const char *zExpr;
+  int nExpr;
+  int nCol;
+  int ii;
+  Fts3Expr *pExpr;
+  sqlite3 *db = sqlite3_context_db_handle(context);
 
-/* Put terms with data this big in their own block. */
-#define STANDALONE_MIN 1024
-
-/* Keep leaf blocks below this size. */
-#define LEAF_MAX 2048
-
-typedef struct LeafWriter {
-  int iLevel;
-  int idx;
-  sqlite_int64 iStartBlockid;     /* needed to create the root info */
-  sqlite_int64 iEndBlockid;       /* when we're done writing. */
-
-  DataBuffer term;                /* previous encoded term */
-  DataBuffer data;                /* encoding buffer */
+  if( argc<3 ){
+    sqlite3_result_error(context, 
+        "Usage: fts3_exprtest(tokenizer, expr, col1, ...", -1
+    );
+    return;
+  }
 
-  /* bytes of first term in the current node which distinguishes that
-  ** term from the last term of the previous node.
-  */
-  int nTermDistinct;
+  rc = queryTestTokenizer(db,
+                          (const char *)sqlite3_value_text(argv[0]), &pModule);
+  if( rc==SQLITE_NOMEM ){
+    sqlite3_result_error_nomem(context);
+    goto exprtest_out;
+  }else if( !pModule ){
+    sqlite3_result_error(context, "No such tokenizer module", -1);
+    goto exprtest_out;
+  }
 
-  InteriorWriter parentWriter;    /* if we overflow */
-  int has_parent;
-} LeafWriter;
+  rc = pModule->xCreate(0, 0, &pTokenizer);
+  assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
+  if( rc==SQLITE_NOMEM ){
+    sqlite3_result_error_nomem(context);
+    goto exprtest_out;
+  }
+  pTokenizer->pModule = pModule;
 
-static void leafWriterInit(int iLevel, int idx, LeafWriter *pWriter){
-  CLEAR(pWriter);
-  pWriter->iLevel = iLevel;
-  pWriter->idx = idx;
+  zExpr = (const char *)sqlite3_value_text(argv[1]);
+  nExpr = sqlite3_value_bytes(argv[1]);
+  nCol = argc-2;
+  azCol = (char **)sqlite3_malloc(nCol*sizeof(char *));
+  if( !azCol ){
+    sqlite3_result_error_nomem(context);
+    goto exprtest_out;
+  }
+  for(ii=0; ii<nCol; ii++){
+    azCol[ii] = (char *)sqlite3_value_text(argv[ii+2]);
+  }
 
-  dataBufferInit(&pWriter->term, 32);
+  rc = sqlite3Fts3ExprParse(
+      pTokenizer, azCol, nCol, nCol, zExpr, nExpr, &pExpr
+  );
+  if( rc==SQLITE_NOMEM ){
+    sqlite3_result_error_nomem(context);
+    goto exprtest_out;
+  }else if( rc==SQLITE_OK ){
+    char zBuf[4096];
+    exprToString(pExpr, zBuf);
+    sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+    sqlite3Fts3ExprFree(pExpr);
+  }else{
+    sqlite3_result_error(context, "Error parsing expression", -1);
+  }
 
-  /* Start out with a reasonably sized block, though it can grow. */
-  dataBufferInit(&pWriter->data, LEAF_MAX);
+exprtest_out:
+  if( pModule && pTokenizer ){
+    rc = pModule->xDestroy(pTokenizer);
+  }
+  sqlite3_free(azCol);
 }
 
-#ifndef NDEBUG
-/* Verify that the data is readable as a leaf node. */
-static void leafNodeValidate(const char *pData, int nData){
-  int n, iDummy;
+/*
+** Register the query expression parser test function fts3_exprtest() 
+** with database connection db. 
+*/
+SQLITE_PRIVATE void sqlite3Fts3ExprInitTestInterface(sqlite3* db){
+  sqlite3_create_function(
+      db, "fts3_exprtest", -1, SQLITE_UTF8, 0, fts3ExprTest, 0, 0
+  );
+}
 
-  if( nData==0 ) return;
-  assert( nData>0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
+#endif
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-  /* Must lead with a varint(0) */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( iDummy==0 );
-  assert( n>0 );
-  assert( n<nData );
-  pData += n;
-  nData -= n;
+/************** End of fts3_expr.c *******************************************/
+/************** Begin file fts3_hash.c ***************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of generic hash-tables used in SQLite.
+** We've modified it slightly to serve as a standalone hash table
+** implementation for the full-text indexing module.
+*/
 
-  /* Leading term length and data must fit in buffer. */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( n>0 );
-  assert( iDummy>0 );
-  assert( n+iDummy>0 );
-  assert( n+iDummy<nData );
-  pData += n+iDummy;
-  nData -= n+iDummy;
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  /* Leading term's doclist length and data must fit. */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( n>0 );
-  assert( iDummy>0 );
-  assert( n+iDummy>0 );
-  assert( n+iDummy<=nData );
-  ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
-  pData += n+iDummy;
-  nData -= n+iDummy;
 
-  /* Verify that trailing terms and doclists also are readable. */
-  while( nData!=0 ){
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>=0 );
-    assert( n<nData );
-    pData += n;
-    nData -= n;
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0 );
-    assert( n+iDummy<nData );
-    pData += n+iDummy;
-    nData -= n+iDummy;
 
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0 );
-    assert( n+iDummy<=nData );
-    ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
-    pData += n+iDummy;
-    nData -= n+iDummy;
+/*
+** Malloc and Free functions
+*/
+static void *fts3HashMalloc(int n){
+  void *p = sqlite3_malloc(n);
+  if( p ){
+    memset(p, 0, n);
   }
+  return p;
+}
+static void fts3HashFree(void *p){
+  sqlite3_free(p);
 }
-#define ASSERT_VALID_LEAF_NODE(p, n) leafNodeValidate(p, n)
-#else
-#define ASSERT_VALID_LEAF_NODE(p, n) assert( 1 )
-#endif
 
-/* Flush the current leaf node to %_segments, and adding the resulting
-** blockid and the starting term to the interior node which will
-** contain it.
+/* Turn bulk memory into a hash table object by initializing the
+** fields of the Hash structure.
+**
+** "pNew" is a pointer to the hash table that is to be initialized.
+** keyClass is one of the constants 
+** FTS3_HASH_BINARY or FTS3_HASH_STRING.  The value of keyClass 
+** determines what kind of key the hash table will use.  "copyKey" is
+** true if the hash table should make its own private copy of keys and
+** false if it should just use the supplied pointer.
 */
-static int leafWriterInternalFlush(fulltext_vtab *v, LeafWriter *pWriter,
-                                   int iData, int nData){
-  sqlite_int64 iBlockid = 0;
-  const char *pStartingTerm;
-  int nStartingTerm, rc, n;
+SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash *pNew, int keyClass, int copyKey){
+  assert( pNew!=0 );
+  assert( keyClass>=FTS3_HASH_STRING && keyClass<=FTS3_HASH_BINARY );
+  pNew->keyClass = keyClass;
+  pNew->copyKey = copyKey;
+  pNew->first = 0;
+  pNew->count = 0;
+  pNew->htsize = 0;
+  pNew->ht = 0;
+}
 
-  /* Must have the leading varint(0) flag, plus at least some
-  ** valid-looking data.
-  */
-  assert( nData>2 );
-  assert( iData>=0 );
-  assert( iData+nData<=pWriter->data.nData );
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData+iData, nData);
+/* Remove all entries from a hash table.  Reclaim all memory.
+** Call this routine to delete a hash table or to reset a hash table
+** to the empty state.
+*/
+SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash *pH){
+  fts3HashElem *elem;         /* For looping over all elements of the table */
 
-  rc = block_insert(v, pWriter->data.pData+iData, nData, &iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-  assert( iBlockid!=0 );
+  assert( pH!=0 );
+  elem = pH->first;
+  pH->first = 0;
+  fts3HashFree(pH->ht);
+  pH->ht = 0;
+  pH->htsize = 0;
+  while( elem ){
+    fts3HashElem *next_elem = elem->next;
+    if( pH->copyKey && elem->pKey ){
+      fts3HashFree(elem->pKey);
+    }
+    fts3HashFree(elem);
+    elem = next_elem;
+  }
+  pH->count = 0;
+}
 
-  /* Reconstruct the first term in the leaf for purposes of building
-  ** the interior node.
-  */
-  n = fts3GetVarint32(pWriter->data.pData+iData+1, &nStartingTerm);
-  pStartingTerm = pWriter->data.pData+iData+1+n;
-  assert( pWriter->data.nData>iData+1+n+nStartingTerm );
-  assert( pWriter->nTermDistinct>0 );
-  assert( pWriter->nTermDistinct<=nStartingTerm );
-  nStartingTerm = pWriter->nTermDistinct;
+/*
+** Hash and comparison functions when the mode is FTS3_HASH_STRING
+*/
+static int fts3StrHash(const void *pKey, int nKey){
+  const char *z = (const char *)pKey;
+  int h = 0;
+  if( nKey<=0 ) nKey = (int) strlen(z);
+  while( nKey > 0  ){
+    h = (h<<3) ^ h ^ *z++;
+    nKey--;
+  }
+  return h & 0x7fffffff;
+}
+static int fts3StrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
+  if( n1!=n2 ) return 1;
+  return strncmp((const char*)pKey1,(const char*)pKey2,n1);
+}
 
-  if( pWriter->has_parent ){
-    interiorWriterAppend(&pWriter->parentWriter,
-                         pStartingTerm, nStartingTerm, iBlockid);
+/*
+** Hash and comparison functions when the mode is FTS3_HASH_BINARY
+*/
+static int fts3BinHash(const void *pKey, int nKey){
+  int h = 0;
+  const char *z = (const char *)pKey;
+  while( nKey-- > 0 ){
+    h = (h<<3) ^ h ^ *(z++);
+  }
+  return h & 0x7fffffff;
+}
+static int fts3BinCompare(const void *pKey1, int n1, const void *pKey2, int n2){
+  if( n1!=n2 ) return 1;
+  return memcmp(pKey1,pKey2,n1);
+}
+
+/*
+** Return a pointer to the appropriate hash function given the key class.
+**
+** The C syntax in this function definition may be unfamilar to some 
+** programmers, so we provide the following additional explanation:
+**
+** The name of the function is "ftsHashFunction".  The function takes a
+** single parameter "keyClass".  The return value of ftsHashFunction()
+** is a pointer to another function.  Specifically, the return value
+** of ftsHashFunction() is a pointer to a function that takes two parameters
+** with types "const void*" and "int" and returns an "int".
+*/
+static int (*ftsHashFunction(int keyClass))(const void*,int){
+  if( keyClass==FTS3_HASH_STRING ){
+    return &fts3StrHash;
   }else{
-    interiorWriterInit(1, pStartingTerm, nStartingTerm, iBlockid,
-                       &pWriter->parentWriter);
-    pWriter->has_parent = 1;
+    assert( keyClass==FTS3_HASH_BINARY );
+    return &fts3BinHash;
   }
+}
 
-  /* Track the span of this segment's leaf nodes. */
-  if( pWriter->iEndBlockid==0 ){
-    pWriter->iEndBlockid = pWriter->iStartBlockid = iBlockid;
+/*
+** Return a pointer to the appropriate hash function given the key class.
+**
+** For help in interpreted the obscure C code in the function definition,
+** see the header comment on the previous function.
+*/
+static int (*ftsCompareFunction(int keyClass))(const void*,int,const void*,int){
+  if( keyClass==FTS3_HASH_STRING ){
+    return &fts3StrCompare;
   }else{
-    pWriter->iEndBlockid++;
-    assert( iBlockid==pWriter->iEndBlockid );
+    assert( keyClass==FTS3_HASH_BINARY );
+    return &fts3BinCompare;
   }
+}
 
-  return SQLITE_OK;
+/* Link an element into the hash table
+*/
+static void fts3HashInsertElement(
+  fts3Hash *pH,            /* The complete hash table */
+  struct _fts3ht *pEntry,  /* The entry into which pNew is inserted */
+  fts3HashElem *pNew       /* The element to be inserted */
+){
+  fts3HashElem *pHead;     /* First element already in pEntry */
+  pHead = pEntry->chain;
+  if( pHead ){
+    pNew->next = pHead;
+    pNew->prev = pHead->prev;
+    if( pHead->prev ){ pHead->prev->next = pNew; }
+    else             { pH->first = pNew; }
+    pHead->prev = pNew;
+  }else{
+    pNew->next = pH->first;
+    if( pH->first ){ pH->first->prev = pNew; }
+    pNew->prev = 0;
+    pH->first = pNew;
+  }
+  pEntry->count++;
+  pEntry->chain = pNew;
 }
-static int leafWriterFlush(fulltext_vtab *v, LeafWriter *pWriter){
-  int rc = leafWriterInternalFlush(v, pWriter, 0, pWriter->data.nData);
-  if( rc!=SQLITE_OK ) return rc;
 
-  /* Re-initialize the output buffer. */
-  dataBufferReset(&pWriter->data);
 
-  return SQLITE_OK;
+/* Resize the hash table so that it cantains "new_size" buckets.
+** "new_size" must be a power of 2.  The hash table might fail 
+** to resize if sqliteMalloc() fails.
+*/
+static void fts3Rehash(fts3Hash *pH, int new_size){
+  struct _fts3ht *new_ht;          /* The new hash table */
+  fts3HashElem *elem, *next_elem;  /* For looping over existing elements */
+  int (*xHash)(const void*,int);   /* The hash function */
+
+  assert( (new_size & (new_size-1))==0 );
+  new_ht = (struct _fts3ht *)fts3HashMalloc( new_size*sizeof(struct _fts3ht) );
+  if( new_ht==0 ) return;
+  fts3HashFree(pH->ht);
+  pH->ht = new_ht;
+  pH->htsize = new_size;
+  xHash = ftsHashFunction(pH->keyClass);
+  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
+    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
+    next_elem = elem->next;
+    fts3HashInsertElement(pH, &new_ht[h], elem);
+  }
 }
 
-/* Fetch the root info for the segment.  If the entire leaf fits
-** within ROOT_MAX, then it will be returned directly, otherwise it
-** will be flushed and the root info will be returned from the
-** interior node.  *piEndBlockid is set to the blockid of the last
-** interior or leaf node written to disk (0 if none are written at
-** all).
+/* This function (for internal use only) locates an element in an
+** hash table that matches the given key.  The hash for this key has
+** already been computed and is passed as the 4th parameter.
 */
-static int leafWriterRootInfo(fulltext_vtab *v, LeafWriter *pWriter,
-                              char **ppRootInfo, int *pnRootInfo,
-                              sqlite_int64 *piEndBlockid){
-  /* we can fit the segment entirely inline */
-  if( !pWriter->has_parent && pWriter->data.nData<ROOT_MAX ){
-    *ppRootInfo = pWriter->data.pData;
-    *pnRootInfo = pWriter->data.nData;
-    *piEndBlockid = 0;
-    return SQLITE_OK;
+static fts3HashElem *fts3FindElementByHash(
+  const fts3Hash *pH, /* The pH to be searched */
+  const void *pKey,   /* The key we are searching for */
+  int nKey,
+  int h               /* The hash for this key. */
+){
+  fts3HashElem *elem;            /* Used to loop thru the element list */
+  int count;                     /* Number of elements left to test */
+  int (*xCompare)(const void*,int,const void*,int);  /* comparison function */
+
+  if( pH->ht ){
+    struct _fts3ht *pEntry = &pH->ht[h];
+    elem = pEntry->chain;
+    count = pEntry->count;
+    xCompare = ftsCompareFunction(pH->keyClass);
+    while( count-- && elem ){
+      if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
+        return elem;
+      }
+      elem = elem->next;
+    }
   }
+  return 0;
+}
 
-  /* Flush remaining leaf data. */
-  if( pWriter->data.nData>0 ){
-    int rc = leafWriterFlush(v, pWriter);
-    if( rc!=SQLITE_OK ) return rc;
+/* Remove a single entry from the hash table given a pointer to that
+** element and a hash on the element's key.
+*/
+static void fts3RemoveElementByHash(
+  fts3Hash *pH,         /* The pH containing "elem" */
+  fts3HashElem* elem,   /* The element to be removed from the pH */
+  int h                 /* Hash value for the element */
+){
+  struct _fts3ht *pEntry;
+  if( elem->prev ){
+    elem->prev->next = elem->next; 
+  }else{
+    pH->first = elem->next;
+  }
+  if( elem->next ){
+    elem->next->prev = elem->prev;
+  }
+  pEntry = &pH->ht[h];
+  if( pEntry->chain==elem ){
+    pEntry->chain = elem->next;
+  }
+  pEntry->count--;
+  if( pEntry->count<=0 ){
+    pEntry->chain = 0;
+  }
+  if( pH->copyKey && elem->pKey ){
+    fts3HashFree(elem->pKey);
+  }
+  fts3HashFree( elem );
+  pH->count--;
+  if( pH->count<=0 ){
+    assert( pH->first==0 );
+    assert( pH->count==0 );
+    fts3HashClear(pH);
   }
-
-  /* We must have flushed a leaf at some point. */
-  assert( pWriter->has_parent );
-
-  /* Tenatively set the end leaf blockid as the end blockid.  If the
-  ** interior node can be returned inline, this will be the final
-  ** blockid, otherwise it will be overwritten by
-  ** interiorWriterRootInfo().
-  */
-  *piEndBlockid = pWriter->iEndBlockid;
-
-  return interiorWriterRootInfo(v, &pWriter->parentWriter,
-                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/* Collect the rootInfo data and store it into the segment directory.
-** This has the effect of flushing the segment's leaf data to
-** %_segments, and also flushing any interior nodes to %_segments.
+/* Attempt to locate an element of the hash table pH with a key
+** that matches pKey,nKey.  Return the data for this element if it is
+** found, or NULL if there is no match.
 */
-static int leafWriterFinalize(fulltext_vtab *v, LeafWriter *pWriter){
-  sqlite_int64 iEndBlockid;
-  char *pRootInfo;
-  int rc, nRootInfo;
-
-  rc = leafWriterRootInfo(v, pWriter, &pRootInfo, &nRootInfo, &iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-
-  /* Don't bother storing an entirely empty segment. */
-  if( iEndBlockid==0 && nRootInfo==0 ) return SQLITE_OK;
-
-  return segdir_set(v, pWriter->iLevel, pWriter->idx,
-                    pWriter->iStartBlockid, pWriter->iEndBlockid,
-                    iEndBlockid, pRootInfo, nRootInfo);
-}
+SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash *pH, const void *pKey, int nKey){
+  int h;                 /* A hash on key */
+  fts3HashElem *elem;    /* The element that matches key */
+  int (*xHash)(const void*,int);  /* The hash function */
 
-static void leafWriterDestroy(LeafWriter *pWriter){
-  if( pWriter->has_parent ) interiorWriterDestroy(&pWriter->parentWriter);
-  dataBufferDestroy(&pWriter->term);
-  dataBufferDestroy(&pWriter->data);
+  if( pH==0 || pH->ht==0 ) return 0;
+  xHash = ftsHashFunction(pH->keyClass);
+  assert( xHash!=0 );
+  h = (*xHash)(pKey,nKey);
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  elem = fts3FindElementByHash(pH,pKey,nKey, h & (pH->htsize-1));
+  return elem ? elem->data : 0;
 }
 
-/* Encode a term into the leafWriter, delta-encoding as appropriate.
-** Returns the length of the new term which distinguishes it from the
-** previous term, which can be used to set nTermDistinct when a node
-** boundary is crossed.
+/* Insert an element into the hash table pH.  The key is pKey,nKey
+** and the data is "data".
+**
+** If no element exists with a matching key, then a new
+** element is created.  A copy of the key is made if the copyKey
+** flag is set.  NULL is returned.
+**
+** If another element already exists with the same key, then the
+** new data replaces the old data and the old data is returned.
+** The key is not copied in this instance.  If a malloc fails, then
+** the new data is returned and the hash table is unchanged.
+**
+** If the "data" parameter to this function is NULL, then the
+** element corresponding to "key" is removed from the hash table.
 */
-static int leafWriterEncodeTerm(LeafWriter *pWriter,
-                                const char *pTerm, int nTerm){
-  char c[VARINT_MAX+VARINT_MAX];
-  int n, nPrefix = 0;
+SQLITE_PRIVATE void *sqlite3Fts3HashInsert(
+  fts3Hash *pH,        /* The hash table to insert into */
+  const void *pKey,    /* The key */
+  int nKey,            /* Number of bytes in the key */
+  void *data           /* The data */
+){
+  int hraw;                 /* Raw hash value of the key */
+  int h;                    /* the hash of the key modulo hash table size */
+  fts3HashElem *elem;       /* Used to loop thru the element list */
+  fts3HashElem *new_elem;   /* New element added to the pH */
+  int (*xHash)(const void*,int);  /* The hash function */
 
-  assert( nTerm>0 );
-  while( nPrefix<pWriter->term.nData &&
-         pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
-    nPrefix++;
-    /* Failing this implies that the terms weren't in order. */
-    assert( nPrefix<nTerm );
+  assert( pH!=0 );
+  xHash = ftsHashFunction(pH->keyClass);
+  assert( xHash!=0 );
+  hraw = (*xHash)(pKey, nKey);
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  h = hraw & (pH->htsize-1);
+  elem = fts3FindElementByHash(pH,pKey,nKey,h);
+  if( elem ){
+    void *old_data = elem->data;
+    if( data==0 ){
+      fts3RemoveElementByHash(pH,elem,h);
+    }else{
+      elem->data = data;
+    }
+    return old_data;
   }
-
-  if( pWriter->data.nData==0 ){
-    /* Encode the node header and leading term as:
-    **  varint(0)
-    **  varint(nTerm)
-    **  char pTerm[nTerm]
-    */
-    n = fts3PutVarint(c, '\0');
-    n += fts3PutVarint(c+n, nTerm);
-    dataBufferAppend2(&pWriter->data, c, n, pTerm, nTerm);
+  if( data==0 ) return 0;
+  if( pH->htsize==0 ){
+    fts3Rehash(pH,8);
+    if( pH->htsize==0 ){
+      pH->count = 0;
+      return data;
+    }
+  }
+  new_elem = (fts3HashElem*)fts3HashMalloc( sizeof(fts3HashElem) );
+  if( new_elem==0 ) return data;
+  if( pH->copyKey && pKey!=0 ){
+    new_elem->pKey = fts3HashMalloc( nKey );
+    if( new_elem->pKey==0 ){
+      fts3HashFree(new_elem);
+      return data;
+    }
+    memcpy((void*)new_elem->pKey, pKey, nKey);
   }else{
-    /* Delta-encode the term as:
-    **  varint(nPrefix)
-    **  varint(nSuffix)
-    **  char pTermSuffix[nSuffix]
-    */
-    n = fts3PutVarint(c, nPrefix);
-    n += fts3PutVarint(c+n, nTerm-nPrefix);
-    dataBufferAppend2(&pWriter->data, c, n, pTerm+nPrefix, nTerm-nPrefix);
+    new_elem->pKey = (void*)pKey;
   }
-  dataBufferReplace(&pWriter->term, pTerm, nTerm);
-
-  return nPrefix+1;
+  new_elem->nKey = nKey;
+  pH->count++;
+  if( pH->count > pH->htsize ){
+    fts3Rehash(pH,pH->htsize*2);
+  }
+  assert( pH->htsize>0 );
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  h = hraw & (pH->htsize-1);
+  fts3HashInsertElement(pH, &pH->ht[h], new_elem);
+  new_elem->data = data;
+  return 0;
 }
 
-/* Used to avoid a memmove when a large amount of doclist data is in
-** the buffer.  This constructs a node and term header before
-** iDoclistData and flushes the resulting complete node using
-** leafWriterInternalFlush().
-*/
-static int leafWriterInlineFlush(fulltext_vtab *v, LeafWriter *pWriter,
-                                 const char *pTerm, int nTerm,
-                                 int iDoclistData){
-  char c[VARINT_MAX+VARINT_MAX];
-  int iData, n = fts3PutVarint(c, 0);
-  n += fts3PutVarint(c+n, nTerm);
-
-  /* There should always be room for the header.  Even if pTerm shared
-  ** a substantial prefix with the previous term, the entire prefix
-  ** could be constructed from earlier data in the doclist, so there
-  ** should be room.
-  */
-  assert( iDoclistData>=n+nTerm );
-
-  iData = iDoclistData-(n+nTerm);
-  memcpy(pWriter->data.pData+iData, c, n);
-  memcpy(pWriter->data.pData+iData+n, pTerm, nTerm);
-
-  return leafWriterInternalFlush(v, pWriter, iData, pWriter->data.nData-iData);
-}
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
-** %_segments.
+/************** End of fts3_hash.c *******************************************/
+/************** Begin file fts3_porter.c *************************************/
+/*
+** 2006 September 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Implementation of the full-text-search tokenizer that implements
+** a Porter stemmer.
 */
-static int leafWriterStepMerge(fulltext_vtab *v, LeafWriter *pWriter,
-                               const char *pTerm, int nTerm,
-                               DLReader *pReaders, int nReaders){
-  char c[VARINT_MAX+VARINT_MAX];
-  int iTermData = pWriter->data.nData, iDoclistData;
-  int i, nData, n, nActualData, nActual, rc, nTermDistinct;
-
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
-  nTermDistinct = leafWriterEncodeTerm(pWriter, pTerm, nTerm);
-
-  /* Remember nTermDistinct if opening a new node. */
-  if( iTermData==0 ) pWriter->nTermDistinct = nTermDistinct;
-
-  iDoclistData = pWriter->data.nData;
-
-  /* Estimate the length of the merged doclist so we can leave space
-  ** to encode it.
-  */
-  for(i=0, nData=0; i<nReaders; i++){
-    nData += dlrAllDataBytes(&pReaders[i]);
-  }
-  n = fts3PutVarint(c, nData);
-  dataBufferAppend(&pWriter->data, c, n);
 
-  docListMerge(&pWriter->data, pReaders, nReaders);
-  ASSERT_VALID_DOCLIST(DL_DEFAULT,
-                       pWriter->data.pData+iDoclistData+n,
-                       pWriter->data.nData-iDoclistData-n, NULL);
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  /* The actual amount of doclist data at this point could be smaller
-  ** than the length we encoded.  Additionally, the space required to
-  ** encode this length could be smaller.  For small doclists, this is
-  ** not a big deal, we can just use memmove() to adjust things.
-  */
-  nActualData = pWriter->data.nData-(iDoclistData+n);
-  nActual = fts3PutVarint(c, nActualData);
-  assert( nActualData<=nData );
-  assert( nActual<=n );
 
-  /* If the new doclist is big enough for force a standalone leaf
-  ** node, we can immediately flush it inline without doing the
-  ** memmove().
-  */
-  /* TODO(shess) This test matches leafWriterStep(), which does this
-  ** test before it knows the cost to varint-encode the term and
-  ** doclist lengths.  At some point, change to
-  ** pWriter->data.nData-iTermData>STANDALONE_MIN.
-  */
-  if( nTerm+nActualData>STANDALONE_MIN ){
-    /* Push leaf node from before this term. */
-    if( iTermData>0 ){
-      rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
-      if( rc!=SQLITE_OK ) return rc;
 
-      pWriter->nTermDistinct = nTermDistinct;
-    }
 
-    /* Fix the encoded doclist length. */
-    iDoclistData += n - nActual;
-    memcpy(pWriter->data.pData+iDoclistData, c, nActual);
+/*
+** Class derived from sqlite3_tokenizer
+*/
+typedef struct porter_tokenizer {
+  sqlite3_tokenizer base;      /* Base class */
+} porter_tokenizer;
 
-    /* Push the standalone leaf node. */
-    rc = leafWriterInlineFlush(v, pWriter, pTerm, nTerm, iDoclistData);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Class derived from sqlit3_tokenizer_cursor
+*/
+typedef struct porter_tokenizer_cursor {
+  sqlite3_tokenizer_cursor base;
+  const char *zInput;          /* input we are tokenizing */
+  int nInput;                  /* size of the input */
+  int iOffset;                 /* current position in zInput */
+  int iToken;                  /* index of next token to be returned */
+  char *zToken;                /* storage for current token */
+  int nAllocated;              /* space allocated to zToken buffer */
+} porter_tokenizer_cursor;
 
-    /* Leave the node empty. */
-    dataBufferReset(&pWriter->data);
 
-    return rc;
-  }
+/* Forward declaration */
+static const sqlite3_tokenizer_module porterTokenizerModule;
 
-  /* At this point, we know that the doclist was small, so do the
-  ** memmove if indicated.
-  */
-  if( nActual<n ){
-    memmove(pWriter->data.pData+iDoclistData+nActual,
-            pWriter->data.pData+iDoclistData+n,
-            pWriter->data.nData-(iDoclistData+n));
-    pWriter->data.nData -= n-nActual;
-  }
 
-  /* Replace written length with actual length. */
-  memcpy(pWriter->data.pData+iDoclistData, c, nActual);
+/*
+** Create a new tokenizer instance.
+*/
+static int porterCreate(
+  int argc, const char * const *argv,
+  sqlite3_tokenizer **ppTokenizer
+){
+  porter_tokenizer *t;
+  t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
+  if( t==NULL ) return SQLITE_NOMEM;
+  memset(t, 0, sizeof(*t));
+  *ppTokenizer = &t->base;
+  return SQLITE_OK;
+}
 
-  /* If the node is too large, break things up. */
-  /* TODO(shess) This test matches leafWriterStep(), which does this
-  ** test before it knows the cost to varint-encode the term and
-  ** doclist lengths.  At some point, change to
-  ** pWriter->data.nData>LEAF_MAX.
-  */
-  if( iTermData+nTerm+nActualData>LEAF_MAX ){
-    /* Flush out the leading data as a node */
-    rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Destroy a tokenizer
+*/
+static int porterDestroy(sqlite3_tokenizer *pTokenizer){
+  sqlite3_free(pTokenizer);
+  return SQLITE_OK;
+}
 
-    pWriter->nTermDistinct = nTermDistinct;
+/*
+** Prepare to begin tokenizing a particular string.  The input
+** string to be tokenized is zInput[0..nInput-1].  A cursor
+** used to incrementally tokenize this string is returned in 
+** *ppCursor.
+*/
+static int porterOpen(
+  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
+  const char *zInput, int nInput,        /* String to be tokenized */
+  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
+){
+  porter_tokenizer_cursor *c;
 
-    /* Rebuild header using the current term */
-    n = fts3PutVarint(pWriter->data.pData, 0);
-    n += fts3PutVarint(pWriter->data.pData+n, nTerm);
-    memcpy(pWriter->data.pData+n, pTerm, nTerm);
-    n += nTerm;
+  c = (porter_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
+  if( c==NULL ) return SQLITE_NOMEM;
 
-    /* There should always be room, because the previous encoding
-    ** included all data necessary to construct the term.
-    */
-    assert( n<iDoclistData );
-    /* So long as STANDALONE_MIN is half or less of LEAF_MAX, the
-    ** following memcpy() is safe (as opposed to needing a memmove).
-    */
-    assert( 2*STANDALONE_MIN<=LEAF_MAX );
-    assert( n+pWriter->data.nData-iDoclistData<iDoclistData );
-    memcpy(pWriter->data.pData+n,
-           pWriter->data.pData+iDoclistData,
-           pWriter->data.nData-iDoclistData);
-    pWriter->data.nData -= iDoclistData-n;
+  c->zInput = zInput;
+  if( zInput==0 ){
+    c->nInput = 0;
+  }else if( nInput<0 ){
+    c->nInput = (int)strlen(zInput);
+  }else{
+    c->nInput = nInput;
   }
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
+  c->iOffset = 0;                 /* start tokenizing at the beginning */
+  c->iToken = 0;
+  c->zToken = NULL;               /* no space allocated, yet. */
+  c->nAllocated = 0;
 
+  *ppCursor = &c->base;
   return SQLITE_OK;
 }
 
-/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
-** %_segments.
+/*
+** Close a tokenization cursor previously opened by a call to
+** porterOpen() above.
 */
-/* TODO(shess) Revise writeZeroSegment() so that doclists are
-** constructed directly in pWriter->data.
+static int porterClose(sqlite3_tokenizer_cursor *pCursor){
+  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
+  sqlite3_free(c->zToken);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
+/*
+** Vowel or consonant
 */
-static int leafWriterStep(fulltext_vtab *v, LeafWriter *pWriter,
-                          const char *pTerm, int nTerm,
-                          const char *pData, int nData){
-  int rc;
-  DLReader reader;
+static const char cType[] = {
+   0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,
+   1, 1, 1, 2, 1
+};
 
-  dlrInit(&reader, DL_DEFAULT, pData, nData);
-  rc = leafWriterStepMerge(v, pWriter, pTerm, nTerm, &reader, 1);
-  dlrDestroy(&reader);
+/*
+** isConsonant() and isVowel() determine if their first character in
+** the string they point to is a consonant or a vowel, according
+** to Porter ruls.  
+**
+** A consonate is any letter other than 'a', 'e', 'i', 'o', or 'u'.
+** 'Y' is a consonant unless it follows another consonant,
+** in which case it is a vowel.
+**
+** In these routine, the letters are in reverse order.  So the 'y' rule
+** is that 'y' is a consonant unless it is followed by another
+** consonent.
+*/
+static int isVowel(const char*);
+static int isConsonant(const char *z){
+  int j;
+  char x = *z;
+  if( x==0 ) return 0;
+  assert( x>='a' && x<='z' );
+  j = cType[x-'a'];
+  if( j<2 ) return j;
+  return z[1]==0 || isVowel(z + 1);
+}
+static int isVowel(const char *z){
+  int j;
+  char x = *z;
+  if( x==0 ) return 0;
+  assert( x>='a' && x<='z' );
+  j = cType[x-'a'];
+  if( j<2 ) return 1-j;
+  return isConsonant(z + 1);
+}
 
-  return rc;
+/*
+** Let any sequence of one or more vowels be represented by V and let
+** C be sequence of one or more consonants.  Then every word can be
+** represented as:
+**
+**           [C] (VC){m} [V]
+**
+** In prose:  A word is an optional consonant followed by zero or
+** vowel-consonant pairs followed by an optional vowel.  "m" is the
+** number of vowel consonant pairs.  This routine computes the value
+** of m for the first i bytes of a word.
+**
+** Return true if the m-value for z is 1 or more.  In other words,
+** return true if z contains at least one vowel that is followed
+** by a consonant.
+**
+** In this routine z[] is in reverse order.  So we are really looking
+** for an instance of of a consonant followed by a vowel.
+*/
+static int m_gt_0(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
 }
 
+/* Like mgt0 above except we are looking for a value of m which is
+** exactly 1
+*/
+static int m_eq_1(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 1;
+  while( isConsonant(z) ){ z++; }
+  return *z==0;
+}
 
-/****************************************************************/
-/* LeafReader is used to iterate over an individual leaf node. */
-typedef struct LeafReader {
-  DataBuffer term;          /* copy of current term. */
+/* Like mgt0 above except we are looking for a value of m>1 instead
+** or m>0
+*/
+static int m_gt_1(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
+}
 
-  const char *pData;        /* data for current term. */
-  int nData;
-} LeafReader;
+/*
+** Return TRUE if there is a vowel anywhere within z[0..n-1]
+*/
+static int hasVowel(const char *z){
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
+}
 
-static void leafReaderDestroy(LeafReader *pReader){
-  dataBufferDestroy(&pReader->term);
-  SCRAMBLE(pReader);
+/*
+** Return TRUE if the word ends in a double consonant.
+**
+** The text is reversed here. So we are really looking at
+** the first two characters of z[].
+*/
+static int doubleConsonant(const char *z){
+  return isConsonant(z) && z[0]==z[1] && isConsonant(z+1);
 }
 
-static int leafReaderAtEnd(LeafReader *pReader){
-  return pReader->nData<=0;
+/*
+** Return TRUE if the word ends with three letters which
+** are consonant-vowel-consonent and where the final consonant
+** is not 'w', 'x', or 'y'.
+**
+** The word is reversed here.  So we are really checking the
+** first three letters and the first one cannot be in [wxy].
+*/
+static int star_oh(const char *z){
+  return
+    z[0]!=0 && isConsonant(z) &&
+    z[0]!='w' && z[0]!='x' && z[0]!='y' &&
+    z[1]!=0 && isVowel(z+1) &&
+    z[2]!=0 && isConsonant(z+2);
 }
 
-/* Access the current term. */
-static int leafReaderTermBytes(LeafReader *pReader){
-  return pReader->term.nData;
-}
-static const char *leafReaderTerm(LeafReader *pReader){
-  assert( pReader->term.nData>0 );
-  return pReader->term.pData;
+/*
+** If the word ends with zFrom and xCond() is true for the stem
+** of the word that preceeds the zFrom ending, then change the 
+** ending to zTo.
+**
+** The input word *pz and zFrom are both in reverse order.  zTo
+** is in normal order. 
+**
+** Return TRUE if zFrom matches.  Return FALSE if zFrom does not
+** match.  Not that TRUE is returned even if xCond() fails and
+** no substitution occurs.
+*/
+static int stem(
+  char **pz,             /* The word being stemmed (Reversed) */
+  const char *zFrom,     /* If the ending matches this... (Reversed) */
+  const char *zTo,       /* ... change the ending to this (not reversed) */
+  int (*xCond)(const char*)   /* Condition that must be true */
+){
+  char *z = *pz;
+  while( *zFrom && *zFrom==*z ){ z++; zFrom++; }
+  if( *zFrom!=0 ) return 0;
+  if( xCond && !xCond(z) ) return 1;
+  while( *zTo ){
+    *(--z) = *(zTo++);
+  }
+  *pz = z;
+  return 1;
 }
 
-/* Access the doclist data for the current term. */
-static int leafReaderDataBytes(LeafReader *pReader){
-  int nData;
-  assert( pReader->term.nData>0 );
-  fts3GetVarint32(pReader->pData, &nData);
-  return nData;
-}
-static const char *leafReaderData(LeafReader *pReader){
-  int n, nData;
-  assert( pReader->term.nData>0 );
-  n = fts3GetVarint32(pReader->pData, &nData);
-  return pReader->pData+n;
+/*
+** This is the fallback stemmer used when the porter stemmer is
+** inappropriate.  The input word is copied into the output with
+** US-ASCII case folding.  If the input word is too long (more
+** than 20 bytes if it contains no digits or more than 6 bytes if
+** it contains digits) then word is truncated to 20 or 6 bytes
+** by taking 10 or 3 bytes from the beginning and end.
+*/
+static void copy_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
+  int i, mx, j;
+  int hasDigit = 0;
+  for(i=0; i<nIn; i++){
+    int c = zIn[i];
+    if( c>='A' && c<='Z' ){
+      zOut[i] = c - 'A' + 'a';
+    }else{
+      if( c>='0' && c<='9' ) hasDigit = 1;
+      zOut[i] = c;
+    }
+  }
+  mx = hasDigit ? 3 : 10;
+  if( nIn>mx*2 ){
+    for(j=mx, i=nIn-mx; i<nIn; i++, j++){
+      zOut[j] = zOut[i];
+    }
+    i = j;
+  }
+  zOut[i] = 0;
+  *pnOut = i;
 }
 
-static void leafReaderInit(const char *pData, int nData,
-                           LeafReader *pReader){
-  int nTerm, n;
 
-  assert( nData>0 );
-  assert( pData[0]=='\0' );
+/*
+** Stem the input word zIn[0..nIn-1].  Store the output in zOut.
+** zOut is at least big enough to hold nIn bytes.  Write the actual
+** size of the output word (exclusive of the '\0' terminator) into *pnOut.
+**
+** Any upper-case characters in the US-ASCII character set ([A-Z])
+** are converted to lower case.  Upper-case UTF characters are
+** unchanged.
+**
+** Words that are longer than about 20 bytes are stemmed by retaining
+** a few bytes from the beginning and the end of the word.  If the
+** word contains digits, 3 bytes are taken from the beginning and
+** 3 bytes from the end.  For long words without digits, 10 bytes
+** are taken from each end.  US-ASCII case folding still applies.
+** 
+** If the input word contains not digits but does characters not 
+** in [a-zA-Z] then no stemming is attempted and this routine just 
+** copies the input into the input into the output with US-ASCII
+** case folding.
+**
+** Stemming never increases the length of the word.  So there is
+** no chance of overflowing the zOut buffer.
+*/
+static void porter_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
+  int i, j, c;
+  char zReverse[28];
+  char *z, *z2;
+  if( nIn<3 || nIn>=sizeof(zReverse)-7 ){
+    /* The word is too big or too small for the porter stemmer.
+    ** Fallback to the copy stemmer */
+    copy_stemmer(zIn, nIn, zOut, pnOut);
+    return;
+  }
+  for(i=0, j=sizeof(zReverse)-6; i<nIn; i++, j--){
+    c = zIn[i];
+    if( c>='A' && c<='Z' ){
+      zReverse[j] = c + 'a' - 'A';
+    }else if( c>='a' && c<='z' ){
+      zReverse[j] = c;
+    }else{
+      /* The use of a character not in [a-zA-Z] means that we fallback
+      ** to the copy stemmer */
+      copy_stemmer(zIn, nIn, zOut, pnOut);
+      return;
+    }
+  }
+  memset(&zReverse[sizeof(zReverse)-5], 0, 5);
+  z = &zReverse[j+1];
 
-  CLEAR(pReader);
 
-  /* Read the first term, skipping the header byte. */
-  n = fts3GetVarint32(pData+1, &nTerm);
-  dataBufferInit(&pReader->term, nTerm);
-  dataBufferReplace(&pReader->term, pData+1+n, nTerm);
+  /* Step 1a */
+  if( z[0]=='s' ){
+    if(
+     !stem(&z, "sess", "ss", 0) &&
+     !stem(&z, "sei", "i", 0)  &&
+     !stem(&z, "ss", "ss", 0)
+    ){
+      z++;
+    }
+  }
 
-  /* Position after the first term. */
-  assert( 1+n+nTerm<nData );
-  pReader->pData = pData+1+n+nTerm;
-  pReader->nData = nData-1-n-nTerm;
-}
+  /* Step 1b */  
+  z2 = z;
+  if( stem(&z, "dee", "ee", m_gt_0) ){
+    /* Do nothing.  The work was all in the test */
+  }else if( 
+     (stem(&z, "gni", "", hasVowel) || stem(&z, "de", "", hasVowel))
+      && z!=z2
+  ){
+     if( stem(&z, "ta", "ate", 0) ||
+         stem(&z, "lb", "ble", 0) ||
+         stem(&z, "zi", "ize", 0) ){
+       /* Do nothing.  The work was all in the test */
+     }else if( doubleConsonant(z) && (*z!='l' && *z!='s' && *z!='z') ){
+       z++;
+     }else if( m_eq_1(z) && star_oh(z) ){
+       *(--z) = 'e';
+     }
+  }
 
-/* Step the reader forward to the next term. */
-static void leafReaderStep(LeafReader *pReader){
-  int n, nData, nPrefix, nSuffix;
-  assert( !leafReaderAtEnd(pReader) );
+  /* Step 1c */
+  if( z[0]=='y' && hasVowel(z+1) ){
+    z[0] = 'i';
+  }
 
-  /* Skip previous entry's data block. */
-  n = fts3GetVarint32(pReader->pData, &nData);
-  assert( n+nData<=pReader->nData );
-  pReader->pData += n+nData;
-  pReader->nData -= n+nData;
+  /* Step 2 */
+  switch( z[1] ){
+   case 'a':
+     stem(&z, "lanoita", "ate", m_gt_0) ||
+     stem(&z, "lanoit", "tion", m_gt_0);
+     break;
+   case 'c':
+     stem(&z, "icne", "ence", m_gt_0) ||
+     stem(&z, "icna", "ance", m_gt_0);
+     break;
+   case 'e':
+     stem(&z, "rezi", "ize", m_gt_0);
+     break;
+   case 'g':
+     stem(&z, "igol", "log", m_gt_0);
+     break;
+   case 'l':
+     stem(&z, "ilb", "ble", m_gt_0) ||
+     stem(&z, "illa", "al", m_gt_0) ||
+     stem(&z, "iltne", "ent", m_gt_0) ||
+     stem(&z, "ile", "e", m_gt_0) ||
+     stem(&z, "ilsuo", "ous", m_gt_0);
+     break;
+   case 'o':
+     stem(&z, "noitazi", "ize", m_gt_0) ||
+     stem(&z, "noita", "ate", m_gt_0) ||
+     stem(&z, "rota", "ate", m_gt_0);
+     break;
+   case 's':
+     stem(&z, "msila", "al", m_gt_0) ||
+     stem(&z, "ssenevi", "ive", m_gt_0) ||
+     stem(&z, "ssenluf", "ful", m_gt_0) ||
+     stem(&z, "ssensuo", "ous", m_gt_0);
+     break;
+   case 't':
+     stem(&z, "itila", "al", m_gt_0) ||
+     stem(&z, "itivi", "ive", m_gt_0) ||
+     stem(&z, "itilib", "ble", m_gt_0);
+     break;
+  }
 
-  if( !leafReaderAtEnd(pReader) ){
-    /* Construct the new term using a prefix from the old term plus a
-    ** suffix from the leaf data.
-    */
-    n = fts3GetVarint32(pReader->pData, &nPrefix);
-    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
-    assert( n+nSuffix<pReader->nData );
-    pReader->term.nData = nPrefix;
-    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
+  /* Step 3 */
+  switch( z[0] ){
+   case 'e':
+     stem(&z, "etaci", "ic", m_gt_0) ||
+     stem(&z, "evita", "", m_gt_0)   ||
+     stem(&z, "ezila", "al", m_gt_0);
+     break;
+   case 'i':
+     stem(&z, "itici", "ic", m_gt_0);
+     break;
+   case 'l':
+     stem(&z, "laci", "ic", m_gt_0) ||
+     stem(&z, "luf", "", m_gt_0);
+     break;
+   case 's':
+     stem(&z, "ssen", "", m_gt_0);
+     break;
+  }
 
-    pReader->pData += n+nSuffix;
-    pReader->nData -= n+nSuffix;
+  /* Step 4 */
+  switch( z[1] ){
+   case 'a':
+     if( z[0]=='l' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'c':
+     if( z[0]=='e' && z[2]=='n' && (z[3]=='a' || z[3]=='e')  && m_gt_1(z+4)  ){
+       z += 4;
+     }
+     break;
+   case 'e':
+     if( z[0]=='r' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'i':
+     if( z[0]=='c' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'l':
+     if( z[0]=='e' && z[2]=='b' && (z[3]=='a' || z[3]=='i') && m_gt_1(z+4) ){
+       z += 4;
+     }
+     break;
+   case 'n':
+     if( z[0]=='t' ){
+       if( z[2]=='a' ){
+         if( m_gt_1(z+3) ){
+           z += 3;
+         }
+       }else if( z[2]=='e' ){
+         stem(&z, "tneme", "", m_gt_1) ||
+         stem(&z, "tnem", "", m_gt_1) ||
+         stem(&z, "tne", "", m_gt_1);
+       }
+     }
+     break;
+   case 'o':
+     if( z[0]=='u' ){
+       if( m_gt_1(z+2) ){
+         z += 2;
+       }
+     }else if( z[3]=='s' || z[3]=='t' ){
+       stem(&z, "noi", "", m_gt_1);
+     }
+     break;
+   case 's':
+     if( z[0]=='m' && z[2]=='i' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
+   case 't':
+     stem(&z, "eta", "", m_gt_1) ||
+     stem(&z, "iti", "", m_gt_1);
+     break;
+   case 'u':
+     if( z[0]=='s' && z[2]=='o' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
+   case 'v':
+   case 'z':
+     if( z[0]=='e' && z[2]=='i' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
   }
-}
 
-/* strcmp-style comparison of pReader's current term against pTerm.
-** If isPrefix, equality means equal through nTerm bytes.
-*/
-static int leafReaderTermCmp(LeafReader *pReader,
-                             const char *pTerm, int nTerm, int isPrefix){
-  int c, n = pReader->term.nData<nTerm ? pReader->term.nData : nTerm;
-  if( n==0 ){
-    if( pReader->term.nData>0 ) return -1;
-    if(nTerm>0 ) return 1;
-    return 0;
+  /* Step 5a */
+  if( z[0]=='e' ){
+    if( m_gt_1(z+1) ){
+      z++;
+    }else if( m_eq_1(z+1) && !star_oh(z+1) ){
+      z++;
+    }
   }
 
-  c = memcmp(pReader->term.pData, pTerm, n);
-  if( c!=0 ) return c;
-  if( isPrefix && n==nTerm ) return 0;
-  return pReader->term.nData - nTerm;
-}
+  /* Step 5b */
+  if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
+    z++;
+  }
 
+  /* z[] is now the stemmed word in reverse order.  Flip it back
+  ** around into forward order and return.
+  */
+  *pnOut = i = strlen(z);
+  zOut[i] = 0;
+  while( *z ){
+    zOut[--i] = *(z++);
+  }
+}
 
-/****************************************************************/
-/* LeavesReader wraps LeafReader to allow iterating over the entire
-** leaf layer of the tree.
+/*
+** Characters that can be part of a token.  We assume any character
+** whose value is greater than 0x80 (any UTF character) can be
+** part of a token.  In other words, delimiters all must have
+** values of 0x7f or lower.
 */
-typedef struct LeavesReader {
-  int idx;                  /* Index within the segment. */
+static const char porterIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
+};
+#define isDelim(C) (((ch=C)&0x80)==0 && (ch<0x30 || !porterIdChar[ch-0x30]))
 
-  sqlite3_stmt *pStmt;      /* Statement we're streaming leaves from. */
-  int eof;                  /* we've seen SQLITE_DONE from pStmt. */
+/*
+** Extract the next token from a tokenization cursor.  The cursor must
+** have been opened by a prior call to porterOpen().
+*/
+static int porterNext(
+  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by porterOpen */
+  const char **pzToken,               /* OUT: *pzToken is the token text */
+  int *pnBytes,                       /* OUT: Number of bytes in token */
+  int *piStartOffset,                 /* OUT: Starting offset of token */
+  int *piEndOffset,                   /* OUT: Ending offset of token */
+  int *piPosition                     /* OUT: Position integer of token */
+){
+  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
+  const char *z = c->zInput;
 
-  LeafReader leafReader;    /* reader for the current leaf. */
-  DataBuffer rootData;      /* root data for inline. */
-} LeavesReader;
+  while( c->iOffset<c->nInput ){
+    int iStartOffset, ch;
 
-/* Access the current term. */
-static int leavesReaderTermBytes(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderTermBytes(&pReader->leafReader);
-}
-static const char *leavesReaderTerm(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderTerm(&pReader->leafReader);
-}
+    /* Scan past delimiter characters */
+    while( c->iOffset<c->nInput && isDelim(z[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-/* Access the doclist data for the current term. */
-static int leavesReaderDataBytes(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderDataBytes(&pReader->leafReader);
-}
-static const char *leavesReaderData(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderData(&pReader->leafReader);
-}
+    /* Count non-delimiter characters. */
+    iStartOffset = c->iOffset;
+    while( c->iOffset<c->nInput && !isDelim(z[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-static int leavesReaderAtEnd(LeavesReader *pReader){
-  return pReader->eof;
+    if( c->iOffset>iStartOffset ){
+      int n = c->iOffset-iStartOffset;
+      if( n>c->nAllocated ){
+        c->nAllocated = n+20;
+        c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
+        if( c->zToken==NULL ) return SQLITE_NOMEM;
+      }
+      porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
+      *pzToken = c->zToken;
+      *piStartOffset = iStartOffset;
+      *piEndOffset = c->iOffset;
+      *piPosition = c->iToken++;
+      return SQLITE_OK;
+    }
+  }
+  return SQLITE_DONE;
 }
 
-/* loadSegmentLeaves() may not read all the way to SQLITE_DONE, thus
-** leaving the statement handle open, which locks the table.
+/*
+** The set of routines that implement the porter-stemmer tokenizer
 */
-/* TODO(shess) This "solution" is not satisfactory.  Really, there
-** should be check-in function for all statement handles which
-** arranges to call sqlite3_reset().  This most likely will require
-** modification to control flow all over the place, though, so for now
-** just punt.
-**
-** Note the the current system assumes that segment merges will run to
-** completion, which is why this particular probably hasn't arisen in
-** this case.  Probably a brittle assumption.
+static const sqlite3_tokenizer_module porterTokenizerModule = {
+  0,
+  porterCreate,
+  porterDestroy,
+  porterOpen,
+  porterClose,
+  porterNext,
+};
+
+/*
+** Allocate a new porter tokenizer.  Return a pointer to the new
+** tokenizer in *ppModule
 */
-static int leavesReaderReset(LeavesReader *pReader){
-  return sqlite3_reset(pReader->pStmt);
+SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
+  sqlite3_tokenizer_module const**ppModule
+){
+  *ppModule = &porterTokenizerModule;
 }
 
-static void leavesReaderDestroy(LeavesReader *pReader){
-  leafReaderDestroy(&pReader->leafReader);
-  dataBufferDestroy(&pReader->rootData);
-  SCRAMBLE(pReader);
-}
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3_porter.c *****************************************/
+/************** Begin file fts3_tokenizer.c **********************************/
+/*
+** 2007 June 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This is part of an SQLite module implementing full-text search.
+** This particular file implements the generic tokenizer interface.
+*/
 
-/* Initialize pReader with the given root data (if iStartBlockid==0
-** the leaf data was entirely contained in the root), or from the
-** stream of blocks between iStartBlockid and iEndBlockid, inclusive.
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
 */
-static int leavesReaderInit(fulltext_vtab *v,
-                            int idx,
-                            sqlite_int64 iStartBlockid,
-                            sqlite_int64 iEndBlockid,
-                            const char *pRootData, int nRootData,
-                            LeavesReader *pReader){
-  CLEAR(pReader);
-  pReader->idx = idx;
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  dataBufferInit(&pReader->rootData, 0);
-  if( iStartBlockid==0 ){
-    /* Entire leaf level fit in root data. */
-    dataBufferReplace(&pReader->rootData, pRootData, nRootData);
-    leafReaderInit(pReader->rootData.pData, pReader->rootData.nData,
-                   &pReader->leafReader);
-  }else{
-    sqlite3_stmt *s;
-    int rc = sql_get_leaf_statement(v, idx, &s);
-    if( rc!=SQLITE_OK ) return rc;
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#endif
 
-    rc = sqlite3_bind_int64(s, 1, iStartBlockid);
-    if( rc!=SQLITE_OK ) return rc;
 
-    rc = sqlite3_bind_int64(s, 2, iEndBlockid);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Implementation of the SQL scalar function for accessing the underlying 
+** hash table. This function may be called as follows:
+**
+**   SELECT <function-name>(<key-name>);
+**   SELECT <function-name>(<key-name>, <pointer>);
+**
+** where <function-name> is the name passed as the second argument
+** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer').
+**
+** If the <pointer> argument is specified, it must be a blob value
+** containing a pointer to be stored as the hash data corresponding
+** to the string <key-name>. If <pointer> is not specified, then
+** the string <key-name> must already exist in the has table. Otherwise,
+** an error is returned.
+**
+** Whether or not the <pointer> argument is specified, the value returned
+** is a blob containing the pointer stored as the hash data corresponding
+** to string <key-name> (after the hash-table is updated, if applicable).
+*/
+static void scalarFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  fts3Hash *pHash;
+  void *pPtr = 0;
+  const unsigned char *zName;
+  int nName;
 
-    rc = sqlite3_step(s);
-    if( rc==SQLITE_DONE ){
-      pReader->eof = 1;
-      return SQLITE_OK;
-    }
-    if( rc!=SQLITE_ROW ) return rc;
+  assert( argc==1 || argc==2 );
 
-    pReader->pStmt = s;
-    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
-                   sqlite3_column_bytes(pReader->pStmt, 0),
-                   &pReader->leafReader);
-  }
-  return SQLITE_OK;
-}
+  pHash = (fts3Hash *)sqlite3_user_data(context);
 
-/* Step the current leaf forward to the next term.  If we reach the
-** end of the current leaf, step forward to the next leaf block.
-*/
-static int leavesReaderStep(fulltext_vtab *v, LeavesReader *pReader){
-  assert( !leavesReaderAtEnd(pReader) );
-  leafReaderStep(&pReader->leafReader);
+  zName = sqlite3_value_text(argv[0]);
+  nName = sqlite3_value_bytes(argv[0])+1;
 
-  if( leafReaderAtEnd(&pReader->leafReader) ){
-    int rc;
-    if( pReader->rootData.pData ){
-      pReader->eof = 1;
-      return SQLITE_OK;
+  if( argc==2 ){
+    void *pOld;
+    int n = sqlite3_value_bytes(argv[1]);
+    if( n!=sizeof(pPtr) ){
+      sqlite3_result_error(context, "argument type mismatch", -1);
+      return;
     }
-    rc = sqlite3_step(pReader->pStmt);
-    if( rc!=SQLITE_ROW ){
-      pReader->eof = 1;
-      return rc==SQLITE_DONE ? SQLITE_OK : rc;
+    pPtr = *(void **)sqlite3_value_blob(argv[1]);
+    pOld = sqlite3Fts3HashInsert(pHash, (void *)zName, nName, pPtr);
+    if( pOld==pPtr ){
+      sqlite3_result_error(context, "out of memory", -1);
+      return;
+    }
+  }else{
+    pPtr = sqlite3Fts3HashFind(pHash, zName, nName);
+    if( !pPtr ){
+      char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
+      sqlite3_result_error(context, zErr, -1);
+      sqlite3_free(zErr);
+      return;
     }
-    leafReaderDestroy(&pReader->leafReader);
-    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
-                   sqlite3_column_bytes(pReader->pStmt, 0),
-                   &pReader->leafReader);
   }
-  return SQLITE_OK;
+
+  sqlite3_result_blob(context, (void *)&pPtr, sizeof(pPtr), SQLITE_TRANSIENT);
 }
 
-/* Order LeavesReaders by their term, ignoring idx.  Readers at eof
-** always sort to the end.
-*/
-static int leavesReaderTermCmp(LeavesReader *lr1, LeavesReader *lr2){
-  if( leavesReaderAtEnd(lr1) ){
-    if( leavesReaderAtEnd(lr2) ) return 0;
-    return 1;
-  }
-  if( leavesReaderAtEnd(lr2) ) return -1;
+#ifdef SQLITE_TEST
 
-  return leafReaderTermCmp(&lr1->leafReader,
-                           leavesReaderTerm(lr2), leavesReaderTermBytes(lr2),
-                           0);
-}
 
-/* Similar to leavesReaderTermCmp(), with additional ordering by idx
-** so that older segments sort before newer segments.
+/*
+** Implementation of a special SQL scalar function for testing tokenizers 
+** designed to be used in concert with the Tcl testing framework. This
+** function must be called with two arguments:
+**
+**   SELECT <function-name>(<key-name>, <input-string>);
+**   SELECT <function-name>(<key-name>, <pointer>);
+**
+** where <function-name> is the name passed as the second argument
+** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
+** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
+**
+** The return value is a string that may be interpreted as a Tcl
+** list. For each token in the <input-string>, three elements are
+** added to the returned list. The first is the token position, the 
+** second is the token text (folded, stemmed, etc.) and the third is the
+** substring of <input-string> associated with the token. For example, 
+** using the built-in "simple" tokenizer:
+**
+**   SELECT fts_tokenizer_test('simple', 'I don't see how');
+**
+** will return the string:
+**
+**   "{0 i I 1 dont don't 2 see see 3 how how}"
+**   
 */
-static int leavesReaderCmp(LeavesReader *lr1, LeavesReader *lr2){
-  int c = leavesReaderTermCmp(lr1, lr2);
-  if( c!=0 ) return c;
-  return lr1->idx-lr2->idx;
-}
+static void testFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  fts3Hash *pHash;
+  sqlite3_tokenizer_module *p;
+  sqlite3_tokenizer *pTokenizer = 0;
+  sqlite3_tokenizer_cursor *pCsr = 0;
 
-/* Assume that pLr[1]..pLr[nLr] are sorted.  Bubble pLr[0] into its
-** sorted position.
-*/
-static void leavesReaderReorder(LeavesReader *pLr, int nLr){
-  while( nLr>1 && leavesReaderCmp(pLr, pLr+1)>0 ){
-    LeavesReader tmp = pLr[0];
-    pLr[0] = pLr[1];
-    pLr[1] = tmp;
-    nLr--;
-    pLr++;
-  }
-}
+  const char *zErr = 0;
 
-/* Initializes pReaders with the segments from level iLevel, returning
-** the number of segments in *piReaders.  Leaves pReaders in sorted
-** order.
-*/
-static int leavesReadersInit(fulltext_vtab *v, int iLevel,
-                             LeavesReader *pReaders, int *piReaders){
-  sqlite3_stmt *s;
-  int i, rc = sql_get_statement(v, SEGDIR_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+  const char *zName;
+  int nName;
+  const char *zInput;
+  int nInput;
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+  const char *zArg = 0;
 
-  i = 0;
-  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
-    sqlite_int64 iStart = sqlite3_column_int64(s, 0);
-    sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
-    const char *pRootData = sqlite3_column_blob(s, 2);
-    int nRootData = sqlite3_column_bytes(s, 2);
+  const char *zToken;
+  int nToken;
+  int iStart;
+  int iEnd;
+  int iPos;
 
-    assert( i<MERGE_COUNT );
-    rc = leavesReaderInit(v, i, iStart, iEnd, pRootData, nRootData,
-                          &pReaders[i]);
-    if( rc!=SQLITE_OK ) break;
+  Tcl_Obj *pRet;
 
-    i++;
-  }
-  if( rc!=SQLITE_DONE ){
-    while( i-->0 ){
-      leavesReaderDestroy(&pReaders[i]);
-    }
-    return rc;
+  assert( argc==2 || argc==3 );
+
+  nName = sqlite3_value_bytes(argv[0]);
+  zName = (const char *)sqlite3_value_text(argv[0]);
+  nInput = sqlite3_value_bytes(argv[argc-1]);
+  zInput = (const char *)sqlite3_value_text(argv[argc-1]);
+
+  if( argc==3 ){
+    zArg = (const char *)sqlite3_value_text(argv[1]);
   }
 
-  *piReaders = i;
+  pHash = (fts3Hash *)sqlite3_user_data(context);
+  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
 
-  /* Leave our results sorted by term, then age. */
-  while( i-- ){
-    leavesReaderReorder(pReaders+i, *piReaders-i);
+  if( !p ){
+    char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
+    sqlite3_result_error(context, zErr, -1);
+    sqlite3_free(zErr);
+    return;
   }
-  return SQLITE_OK;
-}
 
-/* Merge doclists from pReaders[nReaders] into a single doclist, which
-** is written to pWriter.  Assumes pReaders is ordered oldest to
-** newest.
-*/
-/* TODO(shess) Consider putting this inline in segmentMerge(). */
-static int leavesReadersMerge(fulltext_vtab *v,
-                              LeavesReader *pReaders, int nReaders,
-                              LeafWriter *pWriter){
-  DLReader dlReaders[MERGE_COUNT];
-  const char *pTerm = leavesReaderTerm(pReaders);
-  int i, nTerm = leavesReaderTermBytes(pReaders);
+  pRet = Tcl_NewObj();
+  Tcl_IncrRefCount(pRet);
 
-  assert( nReaders<=MERGE_COUNT );
+  if( SQLITE_OK!=p->xCreate(zArg ? 1 : 0, &zArg, &pTokenizer) ){
+    zErr = "error in xCreate()";
+    goto finish;
+  }
+  pTokenizer->pModule = p;
+  if( SQLITE_OK!=p->xOpen(pTokenizer, zInput, nInput, &pCsr) ){
+    zErr = "error in xOpen()";
+    goto finish;
+  }
+  pCsr->pTokenizer = pTokenizer;
 
-  for(i=0; i<nReaders; i++){
-    dlrInit(&dlReaders[i], DL_DEFAULT,
-            leavesReaderData(pReaders+i),
-            leavesReaderDataBytes(pReaders+i));
+  while( SQLITE_OK==p->xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
+    zToken = &zInput[iStart];
+    nToken = iEnd-iStart;
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
   }
 
-  return leafWriterStepMerge(v, pWriter, pTerm, nTerm, dlReaders, nReaders);
+  if( SQLITE_OK!=p->xClose(pCsr) ){
+    zErr = "error in xClose()";
+    goto finish;
+  }
+  if( SQLITE_OK!=p->xDestroy(pTokenizer) ){
+    zErr = "error in xDestroy()";
+    goto finish;
+  }
+
+finish:
+  if( zErr ){
+    sqlite3_result_error(context, zErr, -1);
+  }else{
+    sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
+  }
+  Tcl_DecrRefCount(pRet);
 }
 
-/* Forward ref due to mutual recursion with segdirNextIndex(). */
-static int segmentMerge(fulltext_vtab *v, int iLevel);
+static
+int registerTokenizer(
+  sqlite3 *db, 
+  char *zName, 
+  const sqlite3_tokenizer_module *p
+){
+  int rc;
+  sqlite3_stmt *pStmt;
+  const char zSql[] = "SELECT fts3_tokenizer(?, ?)";
 
-/* Put the next available index at iLevel into *pidx.  If iLevel
-** already has MERGE_COUNT segments, they are merged to a higher
-** level to make room.
-*/
-static int segdirNextIndex(fulltext_vtab *v, int iLevel, int *pidx){
-  int rc = segdir_max_index(v, iLevel, pidx);
-  if( rc==SQLITE_DONE ){              /* No segments at iLevel. */
-    *pidx = 0;
-  }else if( rc==SQLITE_ROW ){
-    if( *pidx==(MERGE_COUNT-1) ){
-      rc = segmentMerge(v, iLevel);
-      if( rc!=SQLITE_OK ) return rc;
-      *pidx = 0;
-    }else{
-      (*pidx)++;
-    }
-  }else{
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ){
     return rc;
   }
-  return SQLITE_OK;
-}
 
-/* Merge MERGE_COUNT segments at iLevel into a new segment at
-** iLevel+1.  If iLevel+1 is already full of segments, those will be
-** merged to make room.
-*/
-static int segmentMerge(fulltext_vtab *v, int iLevel){
-  LeafWriter writer;
-  LeavesReader lrs[MERGE_COUNT];
-  int i, rc, idx = 0;
+  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
+  sqlite3_bind_blob(pStmt, 2, &p, sizeof(p), SQLITE_STATIC);
+  sqlite3_step(pStmt);
 
-  /* Determine the next available segment index at the next level,
-  ** merging as necessary.
-  */
-  rc = segdirNextIndex(v, iLevel+1, &idx);
-  if( rc!=SQLITE_OK ) return rc;
+  return sqlite3_finalize(pStmt);
+}
 
-  /* TODO(shess) This assumes that we'll always see exactly
-  ** MERGE_COUNT segments to merge at a given level.  That will be
-  ** broken if we allow the developer to request preemptive or
-  ** deferred merging.
-  */
-  memset(&lrs, '\0', sizeof(lrs));
-  rc = leavesReadersInit(v, iLevel, lrs, &i);
-  if( rc!=SQLITE_OK ) return rc;
-  assert( i==MERGE_COUNT );
+static
+int queryTokenizer(
+  sqlite3 *db, 
+  char *zName,  
+  const sqlite3_tokenizer_module **pp
+){
+  int rc;
+  sqlite3_stmt *pStmt;
+  const char zSql[] = "SELECT fts3_tokenizer(?)";
 
-  leafWriterInit(iLevel+1, idx, &writer);
+  *pp = 0;
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
 
-  /* Since leavesReaderReorder() pushes readers at eof to the end,
-  ** when the first reader is empty, all will be empty.
-  */
-  while( !leavesReaderAtEnd(lrs) ){
-    /* Figure out how many readers share their next term. */
-    for(i=1; i<MERGE_COUNT && !leavesReaderAtEnd(lrs+i); i++){
-      if( 0!=leavesReaderTermCmp(lrs, lrs+i) ) break;
+  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
+  if( SQLITE_ROW==sqlite3_step(pStmt) ){
+    if( sqlite3_column_type(pStmt, 0)==SQLITE_BLOB ){
+      memcpy(pp, sqlite3_column_blob(pStmt, 0), sizeof(*pp));
     }
+  }
 
-    rc = leavesReadersMerge(v, lrs, i, &writer);
-    if( rc!=SQLITE_OK ) goto err;
+  return sqlite3_finalize(pStmt);
+}
 
-    /* Step forward those that were merged. */
-    while( i-->0 ){
-      rc = leavesReaderStep(v, lrs+i);
-      if( rc!=SQLITE_OK ) goto err;
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
 
-      /* Reorder by term, then by age. */
-      leavesReaderReorder(lrs+i, MERGE_COUNT-i);
-    }
-  }
+/*
+** Implementation of the scalar function fts3_tokenizer_internal_test().
+** This function is used for testing only, it is not included in the
+** build unless SQLITE_TEST is defined.
+**
+** The purpose of this is to test that the fts3_tokenizer() function
+** can be used as designed by the C-code in the queryTokenizer and
+** registerTokenizer() functions above. These two functions are repeated
+** in the README.tokenizer file as an example, so it is important to
+** test them.
+**
+** To run the tests, evaluate the fts3_tokenizer_internal_test() scalar
+** function with no arguments. An assert() will fail if a problem is
+** detected. i.e.:
+**
+**     SELECT fts3_tokenizer_internal_test();
+**
+*/
+static void intTestFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int rc;
+  const sqlite3_tokenizer_module *p1;
+  const sqlite3_tokenizer_module *p2;
+  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
 
-  for(i=0; i<MERGE_COUNT; i++){
-    leavesReaderDestroy(&lrs[i]);
-  }
+  /* Test the query function */
+  sqlite3Fts3SimpleTokenizerModule(&p1);
+  rc = queryTokenizer(db, "simple", &p2);
+  assert( rc==SQLITE_OK );
+  assert( p1==p2 );
+  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
+  assert( rc==SQLITE_ERROR );
+  assert( p2==0 );
+  assert( 0==strcmp(sqlite3_errmsg(db), "unknown tokenizer: nosuchtokenizer") );
 
-  rc = leafWriterFinalize(v, &writer);
-  leafWriterDestroy(&writer);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Test the storage function */
+  rc = registerTokenizer(db, "nosuchtokenizer", p1);
+  assert( rc==SQLITE_OK );
+  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
+  assert( rc==SQLITE_OK );
+  assert( p2==p1 );
 
-  /* Delete the merged segment data. */
-  return segdir_delete(v, iLevel);
+  sqlite3_result_text(context, "ok", -1, SQLITE_STATIC);
+}
 
- err:
-  for(i=0; i<MERGE_COUNT; i++){
-    leavesReaderDestroy(&lrs[i]);
+#endif
+
+/*
+** Set up SQL objects in database db used to access the contents of
+** the hash table pointed to by argument pHash. The hash table must
+** been initialised to use string keys, and to take a private copy 
+** of the key when a value is inserted. i.e. by a call similar to:
+**
+**    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
+**
+** This function adds a scalar function (see header comment above
+** scalarFunc() in this file for details) and, if ENABLE_TABLE is
+** defined at compilation time, a temporary virtual table (see header 
+** comment above struct HashTableVtab) to the database schema. Both 
+** provide read/write access to the contents of *pHash.
+**
+** The third argument to this function, zName, is used as the name
+** of both the scalar and, if created, the virtual table.
+*/
+SQLITE_PRIVATE int sqlite3Fts3InitHashTable(
+  sqlite3 *db, 
+  fts3Hash *pHash, 
+  const char *zName
+){
+  int rc = SQLITE_OK;
+  void *p = (void *)pHash;
+  const int any = SQLITE_ANY;
+  char *zTest = 0;
+  char *zTest2 = 0;
+
+#ifdef SQLITE_TEST
+  void *pdb = (void *)db;
+  zTest = sqlite3_mprintf("%s_test", zName);
+  zTest2 = sqlite3_mprintf("%s_internal_test", zName);
+  if( !zTest || !zTest2 ){
+    rc = SQLITE_NOMEM;
   }
-  leafWriterDestroy(&writer);
-  return rc;
-}
+#endif
 
-/* Accumulate the union of *acc and *pData into *acc. */
-static void docListAccumulateUnion(DataBuffer *acc,
-                                   const char *pData, int nData) {
-  DataBuffer tmp = *acc;
-  dataBufferInit(acc, tmp.nData+nData);
-  docListUnion(tmp.pData, tmp.nData, pData, nData, acc);
-  dataBufferDestroy(&tmp);
+  if( rc!=SQLITE_OK
+   || (rc = sqlite3_create_function(db, zName, 1, any, p, scalarFunc, 0, 0))
+   || (rc = sqlite3_create_function(db, zName, 2, any, p, scalarFunc, 0, 0))
+#ifdef SQLITE_TEST
+   || (rc = sqlite3_create_function(db, zTest, 2, any, p, testFunc, 0, 0))
+   || (rc = sqlite3_create_function(db, zTest, 3, any, p, testFunc, 0, 0))
+   || (rc = sqlite3_create_function(db, zTest2, 0, any, pdb, intTestFunc, 0, 0))
+#endif
+  );
+
+  sqlite3_free(zTest);
+  sqlite3_free(zTest2);
+  return rc;
 }
 
-/* TODO(shess) It might be interesting to explore different merge
-** strategies, here.  For instance, since this is a sorted merge, we
-** could easily merge many doclists in parallel.  With some
-** comprehension of the storage format, we could merge all of the
-** doclists within a leaf node directly from the leaf node's storage.
-** It may be worthwhile to merge smaller doclists before larger
-** doclists, since they can be traversed more quickly - but the
-** results may have less overlap, making them more expensive in a
-** different way.
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3_tokenizer.c **************************************/
+/************** Begin file fts3_tokenizer1.c *********************************/
+/*
+** 2006 Oct 10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** Implementation of the "simple" full-text-search tokenizer.
 */
 
-/* Scan pReader for pTerm/nTerm, and merge the term's doclist over
-** *out (any doclists with duplicate docids overwrite those in *out).
-** Internal function for loadSegmentLeaf().
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
 */
-static int loadSegmentLeavesInt(fulltext_vtab *v, LeavesReader *pReader,
-                                const char *pTerm, int nTerm, int isPrefix,
-                                DataBuffer *out){
-  /* doclist data is accumulated into pBuffers similar to how one does
-  ** increment in binary arithmetic.  If index 0 is empty, the data is
-  ** stored there.  If there is data there, it is merged and the
-  ** results carried into position 1, with further merge-and-carry
-  ** until an empty position is found.
-  */
-  DataBuffer *pBuffers = NULL;
-  int nBuffers = 0, nMaxBuffers = 0, rc;
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  assert( nTerm>0 );
 
-  for(rc=SQLITE_OK; rc==SQLITE_OK && !leavesReaderAtEnd(pReader);
-      rc=leavesReaderStep(v, pReader)){
-    /* TODO(shess) Really want leavesReaderTermCmp(), but that name is
-    ** already taken to compare the terms of two LeavesReaders.  Think
-    ** on a better name.  [Meanwhile, break encapsulation rather than
-    ** use a confusing name.]
-    */
-    int c = leafReaderTermCmp(&pReader->leafReader, pTerm, nTerm, isPrefix);
-    if( c>0 ) break;      /* Past any possible matches. */
-    if( c==0 ){
-      const char *pData = leavesReaderData(pReader);
-      int iBuffer, nData = leavesReaderDataBytes(pReader);
 
-      /* Find the first empty buffer. */
-      for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
-        if( 0==pBuffers[iBuffer].nData ) break;
-      }
 
-      /* Out of buffers, add an empty one. */
-      if( iBuffer==nBuffers ){
-        if( nBuffers==nMaxBuffers ){
-          DataBuffer *p;
-          nMaxBuffers += 20;
+typedef struct simple_tokenizer {
+  sqlite3_tokenizer base;
+  char delim[128];             /* flag ASCII delimiters */
+} simple_tokenizer;
 
-          /* Manual realloc so we can handle NULL appropriately. */
-          p = sqlite3_malloc(nMaxBuffers*sizeof(*pBuffers));
-          if( p==NULL ){
-            rc = SQLITE_NOMEM;
-            break;
-          }
+typedef struct simple_tokenizer_cursor {
+  sqlite3_tokenizer_cursor base;
+  const char *pInput;          /* input we are tokenizing */
+  int nBytes;                  /* size of the input */
+  int iOffset;                 /* current position in pInput */
+  int iToken;                  /* index of next token to be returned */
+  char *pToken;                /* storage for current token */
+  int nTokenAllocated;         /* space allocated to zToken buffer */
+} simple_tokenizer_cursor;
 
-          if( nBuffers>0 ){
-            assert(pBuffers!=NULL);
-            memcpy(p, pBuffers, nBuffers*sizeof(*pBuffers));
-            sqlite3_free(pBuffers);
-          }
-          pBuffers = p;
-        }
-        dataBufferInit(&(pBuffers[nBuffers]), 0);
-        nBuffers++;
-      }
 
-      /* At this point, must have an empty at iBuffer. */
-      assert(iBuffer<nBuffers && pBuffers[iBuffer].nData==0);
+/* Forward declaration */
+static const sqlite3_tokenizer_module simpleTokenizerModule;
 
-      /* If empty was first buffer, no need for merge logic. */
-      if( iBuffer==0 ){
-        dataBufferReplace(&(pBuffers[0]), pData, nData);
-      }else{
-        /* pAcc is the empty buffer the merged data will end up in. */
-        DataBuffer *pAcc = &(pBuffers[iBuffer]);
-        DataBuffer *p = &(pBuffers[0]);
+static int simpleDelim(simple_tokenizer *t, unsigned char c){
+  return c<0x80 && t->delim[c];
+}
 
-        /* Handle position 0 specially to avoid need to prime pAcc
-        ** with pData/nData.
-        */
-        dataBufferSwap(p, pAcc);
-        docListAccumulateUnion(pAcc, pData, nData);
+/*
+** Create a new tokenizer instance.
+*/
+static int simpleCreate(
+  int argc, const char * const *argv,
+  sqlite3_tokenizer **ppTokenizer
+){
+  simple_tokenizer *t;
 
-        /* Accumulate remaining doclists into pAcc. */
-        for(++p; p<pAcc; ++p){
-          docListAccumulateUnion(pAcc, p->pData, p->nData);
+  t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
+  if( t==NULL ) return SQLITE_NOMEM;
+  memset(t, 0, sizeof(*t));
 
-          /* dataBufferReset() could allow a large doclist to blow up
-          ** our memory requirements.
-          */
-          if( p->nCapacity<1024 ){
-            dataBufferReset(p);
-          }else{
-            dataBufferDestroy(p);
-            dataBufferInit(p, 0);
-          }
-        }
+  /* TODO(shess) Delimiters need to remain the same from run to run,
+  ** else we need to reindex.  One solution would be a meta-table to
+  ** track such information in the database, then we'd only want this
+  ** information on the initial create.
+  */
+  if( argc>1 ){
+    int i, n = strlen(argv[1]);
+    for(i=0; i<n; i++){
+      unsigned char ch = argv[1][i];
+      /* We explicitly don't support UTF-8 delimiters for now. */
+      if( ch>=0x80 ){
+        sqlite3_free(t);
+        return SQLITE_ERROR;
       }
+      t->delim[ch] = 1;
     }
-  }
-
-  /* Union all the doclists together into *out. */
-  /* TODO(shess) What if *out is big?  Sigh. */
-  if( rc==SQLITE_OK && nBuffers>0 ){
-    int iBuffer;
-    for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
-      if( pBuffers[iBuffer].nData>0 ){
-        if( out->nData==0 ){
-          dataBufferSwap(out, &(pBuffers[iBuffer]));
-        }else{
-          docListAccumulateUnion(out, pBuffers[iBuffer].pData,
-                                 pBuffers[iBuffer].nData);
-        }
-      }
+  } else {
+    /* Mark non-alphanumeric ASCII characters as delimiters */
+    int i;
+    for(i=1; i<0x80; i++){
+      t->delim[i] = !isalnum(i);
     }
   }
 
-  while( nBuffers-- ){
-    dataBufferDestroy(&(pBuffers[nBuffers]));
-  }
-  if( pBuffers!=NULL ) sqlite3_free(pBuffers);
-
-  return rc;
+  *ppTokenizer = &t->base;
+  return SQLITE_OK;
 }
 
-/* Call loadSegmentLeavesInt() with pData/nData as input. */
-static int loadSegmentLeaf(fulltext_vtab *v, const char *pData, int nData,
-                           const char *pTerm, int nTerm, int isPrefix,
-                           DataBuffer *out){
-  LeavesReader reader;
-  int rc;
-
-  assert( nData>1 );
-  assert( *pData=='\0' );
-  rc = leavesReaderInit(v, 0, 0, 0, pData, nData, &reader);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
-  leavesReaderReset(&reader);
-  leavesReaderDestroy(&reader);
-  return rc;
+/*
+** Destroy a tokenizer
+*/
+static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
+  sqlite3_free(pTokenizer);
+  return SQLITE_OK;
 }
 
-/* Call loadSegmentLeavesInt() with the leaf nodes from iStartLeaf to
-** iEndLeaf (inclusive) as input, and merge the resulting doclist into
-** out.
+/*
+** Prepare to begin tokenizing a particular string.  The input
+** string to be tokenized is pInput[0..nBytes-1].  A cursor
+** used to incrementally tokenize this string is returned in 
+** *ppCursor.
 */
-static int loadSegmentLeaves(fulltext_vtab *v,
-                             sqlite_int64 iStartLeaf, sqlite_int64 iEndLeaf,
-                             const char *pTerm, int nTerm, int isPrefix,
-                             DataBuffer *out){
-  int rc;
-  LeavesReader reader;
+static int simpleOpen(
+  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
+  const char *pInput, int nBytes,        /* String to be tokenized */
+  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
+){
+  simple_tokenizer_cursor *c;
 
-  assert( iStartLeaf<=iEndLeaf );
-  rc = leavesReaderInit(v, 0, iStartLeaf, iEndLeaf, NULL, 0, &reader);
-  if( rc!=SQLITE_OK ) return rc;
+  c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
+  if( c==NULL ) return SQLITE_NOMEM;
 
-  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
-  leavesReaderReset(&reader);
-  leavesReaderDestroy(&reader);
-  return rc;
+  c->pInput = pInput;
+  if( pInput==0 ){
+    c->nBytes = 0;
+  }else if( nBytes<0 ){
+    c->nBytes = (int)strlen(pInput);
+  }else{
+    c->nBytes = nBytes;
+  }
+  c->iOffset = 0;                 /* start tokenizing at the beginning */
+  c->iToken = 0;
+  c->pToken = NULL;               /* no space allocated, yet. */
+  c->nTokenAllocated = 0;
+
+  *ppCursor = &c->base;
+  return SQLITE_OK;
 }
 
-/* Taking pData/nData as an interior node, find the sequence of child
-** nodes which could include pTerm/nTerm/isPrefix.  Note that the
-** interior node terms logically come between the blocks, so there is
-** one more blockid than there are terms (that block contains terms >=
-** the last interior-node term).
+/*
+** Close a tokenization cursor previously opened by a call to
+** simpleOpen() above.
 */
-/* TODO(shess) The calling code may already know that the end child is
-** not worth calculating, because the end may be in a later sibling
-** node.  Consider whether breaking symmetry is worthwhile.  I suspect
-** it is not worthwhile.
+static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
+  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
+  sqlite3_free(c->pToken);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
+
+/*
+** Extract the next token from a tokenization cursor.  The cursor must
+** have been opened by a prior call to simpleOpen().
 */
-static void getChildrenContaining(const char *pData, int nData,
-                                  const char *pTerm, int nTerm, int isPrefix,
-                                  sqlite_int64 *piStartChild,
-                                  sqlite_int64 *piEndChild){
-  InteriorReader reader;
+static int simpleNext(
+  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by simpleOpen */
+  const char **ppToken,               /* OUT: *ppToken is the token text */
+  int *pnBytes,                       /* OUT: Number of bytes in token */
+  int *piStartOffset,                 /* OUT: Starting offset of token */
+  int *piEndOffset,                   /* OUT: Ending offset of token */
+  int *piPosition                     /* OUT: Position integer of token */
+){
+  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
+  simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer;
+  unsigned char *p = (unsigned char *)c->pInput;
 
-  assert( nData>1 );
-  assert( *pData!='\0' );
-  interiorReaderInit(pData, nData, &reader);
+  while( c->iOffset<c->nBytes ){
+    int iStartOffset;
 
-  /* Scan for the first child which could contain pTerm/nTerm. */
-  while( !interiorReaderAtEnd(&reader) ){
-    if( interiorReaderTermCmp(&reader, pTerm, nTerm, 0)>0 ) break;
-    interiorReaderStep(&reader);
-  }
-  *piStartChild = interiorReaderCurrentBlockid(&reader);
+    /* Scan past delimiter characters */
+    while( c->iOffset<c->nBytes && simpleDelim(t, p[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-  /* Keep scanning to find a term greater than our term, using prefix
-  ** comparison if indicated.  If isPrefix is false, this will be the
-  ** same blockid as the starting block.
-  */
-  while( !interiorReaderAtEnd(&reader) ){
-    if( interiorReaderTermCmp(&reader, pTerm, nTerm, isPrefix)>0 ) break;
-    interiorReaderStep(&reader);
-  }
-  *piEndChild = interiorReaderCurrentBlockid(&reader);
+    /* Count non-delimiter characters. */
+    iStartOffset = c->iOffset;
+    while( c->iOffset<c->nBytes && !simpleDelim(t, p[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-  interiorReaderDestroy(&reader);
+    if( c->iOffset>iStartOffset ){
+      int i, n = c->iOffset-iStartOffset;
+      if( n>c->nTokenAllocated ){
+        c->nTokenAllocated = n+20;
+        c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
+        if( c->pToken==NULL ) return SQLITE_NOMEM;
+      }
+      for(i=0; i<n; i++){
+        /* TODO(shess) This needs expansion to handle UTF-8
+        ** case-insensitivity.
+        */
+        unsigned char ch = p[iStartOffset+i];
+        c->pToken[i] = ch<0x80 ? tolower(ch) : ch;
+      }
+      *ppToken = c->pToken;
+      *pnBytes = n;
+      *piStartOffset = iStartOffset;
+      *piEndOffset = c->iOffset;
+      *piPosition = c->iToken++;
 
-  /* Children must ascend, and if !prefix, both must be the same. */
-  assert( *piEndChild>=*piStartChild );
-  assert( isPrefix || *piStartChild==*piEndChild );
+      return SQLITE_OK;
+    }
+  }
+  return SQLITE_DONE;
 }
 
-/* Read block at iBlockid and pass it with other params to
-** getChildrenContaining().
+/*
+** The set of routines that implement the simple tokenizer
 */
-static int loadAndGetChildrenContaining(
-  fulltext_vtab *v,
-  sqlite_int64 iBlockid,
-  const char *pTerm, int nTerm, int isPrefix,
-  sqlite_int64 *piStartChild, sqlite_int64 *piEndChild
+static const sqlite3_tokenizer_module simpleTokenizerModule = {
+  0,
+  simpleCreate,
+  simpleDestroy,
+  simpleOpen,
+  simpleClose,
+  simpleNext,
+};
+
+/*
+** Allocate a new simple tokenizer.  Return a pointer to the new
+** tokenizer in *ppModule
+*/
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(
+  sqlite3_tokenizer_module const**ppModule
 ){
-  sqlite3_stmt *s = NULL;
-  int rc;
+  *ppModule = &simpleTokenizerModule;
+}
 
-  assert( iBlockid!=0 );
-  assert( pTerm!=NULL );
-  assert( nTerm!=0 );        /* TODO(shess) Why not allow this? */
-  assert( piStartChild!=NULL );
-  assert( piEndChild!=NULL );
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-  rc = sql_get_statement(v, BLOCK_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/************** End of fts3_tokenizer1.c *************************************/
+/************** Begin file rtree.c *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code for implementations of the r-tree and r*-tree
+** algorithms packaged as an SQLite virtual table module.
+**
+** $Id: rtree.c,v 1.14 2009/08/06 18:36:47 danielk1977 Exp $
+*/
 
-  rc = sqlite3_bind_int64(s, 1, iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE)
 
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ) return SQLITE_ERROR;
-  if( rc!=SQLITE_ROW ) return rc;
+/*
+** This file contains an implementation of a couple of different variants
+** of the r-tree algorithm. See the README file for further details. The 
+** same data-structure is used for all, but the algorithms for insert and
+** delete operations vary. The variants used are selected at compile time 
+** by defining the following symbols:
+*/
 
-  getChildrenContaining(sqlite3_column_blob(s, 0), sqlite3_column_bytes(s, 0),
-                        pTerm, nTerm, isPrefix, piStartChild, piEndChild);
+/* Either, both or none of the following may be set to activate 
+** r*tree variant algorithms.
+*/
+#define VARIANT_RSTARTREE_CHOOSESUBTREE 0
+#define VARIANT_RSTARTREE_REINSERT      1
 
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain
-   * locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
+/* 
+** Exactly one of the following must be set to 1.
+*/
+#define VARIANT_GUTTMAN_QUADRATIC_SPLIT 0
+#define VARIANT_GUTTMAN_LINEAR_SPLIT    0
+#define VARIANT_RSTARTREE_SPLIT         1
 
-  return SQLITE_OK;
-}
+#define VARIANT_GUTTMAN_SPLIT \
+        (VARIANT_GUTTMAN_LINEAR_SPLIT||VARIANT_GUTTMAN_QUADRATIC_SPLIT)
 
-/* Traverse the tree represented by pData[nData] looking for
-** pTerm[nTerm], placing its doclist into *out.  This is internal to
-** loadSegment() to make error-handling cleaner.
-*/
-static int loadSegmentInt(fulltext_vtab *v, const char *pData, int nData,
-                          sqlite_int64 iLeavesEnd,
-                          const char *pTerm, int nTerm, int isPrefix,
-                          DataBuffer *out){
-  /* Special case where root is a leaf. */
-  if( *pData=='\0' ){
-    return loadSegmentLeaf(v, pData, nData, pTerm, nTerm, isPrefix, out);
-  }else{
-    int rc;
-    sqlite_int64 iStartChild, iEndChild;
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT
+  #define PickNext QuadraticPickNext
+  #define PickSeeds QuadraticPickSeeds
+  #define AssignCells splitNodeGuttman
+#endif
+#if VARIANT_GUTTMAN_LINEAR_SPLIT
+  #define PickNext LinearPickNext
+  #define PickSeeds LinearPickSeeds
+  #define AssignCells splitNodeGuttman
+#endif
+#if VARIANT_RSTARTREE_SPLIT
+  #define AssignCells splitNodeStartree
+#endif
 
-    /* Process pData as an interior node, then loop down the tree
-    ** until we find the set of leaf nodes to scan for the term.
-    */
-    getChildrenContaining(pData, nData, pTerm, nTerm, isPrefix,
-                          &iStartChild, &iEndChild);
-    while( iStartChild>iLeavesEnd ){
-      sqlite_int64 iNextStart, iNextEnd;
-      rc = loadAndGetChildrenContaining(v, iStartChild, pTerm, nTerm, isPrefix,
-                                        &iNextStart, &iNextEnd);
-      if( rc!=SQLITE_OK ) return rc;
 
-      /* If we've branched, follow the end branch, too. */
-      if( iStartChild!=iEndChild ){
-        sqlite_int64 iDummy;
-        rc = loadAndGetChildrenContaining(v, iEndChild, pTerm, nTerm, isPrefix,
-                                          &iDummy, &iNextEnd);
-        if( rc!=SQLITE_OK ) return rc;
-      }
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#else
+#endif
 
-      assert( iNextStart<=iNextEnd );
-      iStartChild = iNextStart;
-      iEndChild = iNextEnd;
-    }
-    assert( iStartChild<=iLeavesEnd );
-    assert( iEndChild<=iLeavesEnd );
 
-    /* Scan through the leaf segments for doclists. */
-    return loadSegmentLeaves(v, iStartChild, iEndChild,
-                             pTerm, nTerm, isPrefix, out);
-  }
-}
+#ifndef SQLITE_AMALGAMATION
+typedef sqlite3_int64 i64;
+typedef unsigned char u8;
+typedef unsigned int u32;
+#endif
 
-/* Call loadSegmentInt() to collect the doclist for pTerm/nTerm, then
-** merge its doclist over *out (any duplicate doclists read from the
-** segment rooted at pData will overwrite those in *out).
-*/
-/* TODO(shess) Consider changing this to determine the depth of the
-** leaves using either the first characters of interior nodes (when
-** ==1, we're one level above the leaves), or the first character of
-** the root (which will describe the height of the tree directly).
-** Either feels somewhat tricky to me.
-*/
-/* TODO(shess) The current merge is likely to be slow for large
-** doclists (though it should process from newest/smallest to
-** oldest/largest, so it may not be that bad).  It might be useful to
-** modify things to allow for N-way merging.  This could either be
-** within a segment, with pairwise merges across segments, or across
-** all segments at once.
-*/
-static int loadSegment(fulltext_vtab *v, const char *pData, int nData,
-                       sqlite_int64 iLeavesEnd,
-                       const char *pTerm, int nTerm, int isPrefix,
-                       DataBuffer *out){
-  DataBuffer result;
-  int rc;
+typedef struct Rtree Rtree;
+typedef struct RtreeCursor RtreeCursor;
+typedef struct RtreeNode RtreeNode;
+typedef struct RtreeCell RtreeCell;
+typedef struct RtreeConstraint RtreeConstraint;
+typedef union RtreeCoord RtreeCoord;
 
-  assert( nData>1 );
+/* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */
+#define RTREE_MAX_DIMENSIONS 5
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+/* Size of hash table Rtree.aHash. This hash table is not expected to
+** ever contain very many entries, so a fixed number of buckets is 
+** used.
+*/
+#define HASHSIZE 128
 
-  dataBufferInit(&result, 0);
-  rc = loadSegmentInt(v, pData, nData, iLeavesEnd,
-                      pTerm, nTerm, isPrefix, &result);
-  if( rc==SQLITE_OK && result.nData>0 ){
-    if( out->nData==0 ){
-      DataBuffer tmp = *out;
-      *out = result;
-      result = tmp;
-    }else{
-      DataBuffer merged;
-      DLReader readers[2];
+/* 
+** An rtree virtual-table object.
+*/
+struct Rtree {
+  sqlite3_vtab base;
+  sqlite3 *db;                /* Host database connection */
+  int iNodeSize;              /* Size in bytes of each node in the node table */
+  int nDim;                   /* Number of dimensions */
+  int nBytesPerCell;          /* Bytes consumed per cell */
+  int iDepth;                 /* Current depth of the r-tree structure */
+  char *zDb;                  /* Name of database containing r-tree table */
+  char *zName;                /* Name of r-tree table */ 
+  RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */ 
+  int nBusy;                  /* Current number of users of this structure */
+
+  /* List of nodes removed during a CondenseTree operation. List is
+  ** linked together via the pointer normally used for hash chains -
+  ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree 
+  ** headed by the node (leaf nodes have RtreeNode.iNode==0).
+  */
+  RtreeNode *pDeleted;
+  int iReinsertHeight;        /* Height of sub-trees Reinsert() has run on */
+
+  /* Statements to read/write/delete a record from xxx_node */
+  sqlite3_stmt *pReadNode;
+  sqlite3_stmt *pWriteNode;
+  sqlite3_stmt *pDeleteNode;
+
+  /* Statements to read/write/delete a record from xxx_rowid */
+  sqlite3_stmt *pReadRowid;
+  sqlite3_stmt *pWriteRowid;
+  sqlite3_stmt *pDeleteRowid;
+
+  /* Statements to read/write/delete a record from xxx_parent */
+  sqlite3_stmt *pReadParent;
+  sqlite3_stmt *pWriteParent;
+  sqlite3_stmt *pDeleteParent;
+
+  int eCoordType;
+};
 
-      dlrInit(&readers[0], DL_DEFAULT, out->pData, out->nData);
-      dlrInit(&readers[1], DL_DEFAULT, result.pData, result.nData);
-      dataBufferInit(&merged, out->nData+result.nData);
-      docListMerge(&merged, readers, 2);
-      dataBufferDestroy(out);
-      *out = merged;
-      dlrDestroy(&readers[0]);
-      dlrDestroy(&readers[1]);
-    }
-  }
-  dataBufferDestroy(&result);
-  return rc;
-}
+/* Possible values for eCoordType: */
+#define RTREE_COORD_REAL32 0
+#define RTREE_COORD_INT32  1
 
-/* Scan the database and merge together the posting lists for the term
-** into *out.
+/*
+** The minimum number of cells allowed for a node is a third of the 
+** maximum. In Gutman's notation:
+**
+**     m = M/3
+**
+** If an R*-tree "Reinsert" operation is required, the same number of
+** cells are removed from the overfull node and reinserted into the tree.
 */
-static int termSelect(fulltext_vtab *v, int iColumn,
-                      const char *pTerm, int nTerm, int isPrefix,
-                      DocListType iType, DataBuffer *out){
-  DataBuffer doclist;
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+#define RTREE_MINCELLS(p) ((((p)->iNodeSize-4)/(p)->nBytesPerCell)/3)
+#define RTREE_REINSERT(p) RTREE_MINCELLS(p)
+#define RTREE_MAXCELLS 51
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+/* 
+** An rtree cursor object.
+*/
+struct RtreeCursor {
+  sqlite3_vtab_cursor base;
+  RtreeNode *pNode;                 /* Node cursor is currently pointing at */
+  int iCell;                        /* Index of current cell in pNode */
+  int iStrategy;                    /* Copy of idxNum search parameter */
+  int nConstraint;                  /* Number of entries in aConstraint */
+  RtreeConstraint *aConstraint;     /* Search constraints. */
+};
 
-  dataBufferInit(&doclist, 0);
+union RtreeCoord {
+  float f;
+  int i;
+};
 
-  /* Traverse the segments from oldest to newest so that newer doclist
-  ** elements for given docids overwrite older elements.
-  */
-  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
-    const char *pData = sqlite3_column_blob(s, 0);
-    const int nData = sqlite3_column_bytes(s, 0);
-    const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
-    rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, isPrefix,
-                     &doclist);
-    if( rc!=SQLITE_OK ) goto err;
-  }
-  if( rc==SQLITE_DONE ){
-    if( doclist.nData!=0 ){
-      /* TODO(shess) The old term_select_all() code applied the column
-      ** restrict as we merged segments, leading to smaller buffers.
-      ** This is probably worthwhile to bring back, once the new storage
-      ** system is checked in.
-      */
-      if( iColumn==v->nColumn) iColumn = -1;
-      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
-                  iColumn, iType, out);
-    }
-    rc = SQLITE_OK;
-  }
+/*
+** The argument is an RtreeCoord. Return the value stored within the RtreeCoord
+** formatted as a double. This macro assumes that local variable pRtree points
+** to the Rtree structure associated with the RtreeCoord.
+*/
+#define DCOORD(coord) (                           \
+  (pRtree->eCoordType==RTREE_COORD_REAL32) ?      \
+    ((double)coord.f) :                           \
+    ((double)coord.i)                             \
+)
 
- err:
-  dataBufferDestroy(&doclist);
-  return rc;
-}
+/*
+** A search constraint.
+*/
+struct RtreeConstraint {
+  int iCoord;                       /* Index of constrained coordinate */
+  int op;                           /* Constraining operation */
+  double rValue;                    /* Constraint value. */
+};
 
-/****************************************************************/
-/* Used to hold hashtable data for sorting. */
-typedef struct TermData {
-  const char *pTerm;
-  int nTerm;
-  DLCollector *pCollector;
-} TermData;
+/* Possible values for RtreeConstraint.op */
+#define RTREE_EQ 0x41
+#define RTREE_LE 0x42
+#define RTREE_LT 0x43
+#define RTREE_GE 0x44
+#define RTREE_GT 0x45
 
-/* Orders TermData elements in strcmp fashion ( <0 for less-than, 0
-** for equal, >0 for greater-than).
+/* 
+** An rtree structure node.
+**
+** Data format (RtreeNode.zData):
+**
+**   1. If the node is the root node (node 1), then the first 2 bytes
+**      of the node contain the tree depth as a big-endian integer.
+**      For non-root nodes, the first 2 bytes are left unused.
+**
+**   2. The next 2 bytes contain the number of entries currently 
+**      stored in the node.
+**
+**   3. The remainder of the node contains the node entries. Each entry
+**      consists of a single 8-byte integer followed by an even number
+**      of 4-byte coordinates. For leaf nodes the integer is the rowid
+**      of a record. For internal nodes it is the node number of a
+**      child page.
 */
-static int termDataCmp(const void *av, const void *bv){
-  const TermData *a = (const TermData *)av;
-  const TermData *b = (const TermData *)bv;
-  int n = a->nTerm<b->nTerm ? a->nTerm : b->nTerm;
-  int c = memcmp(a->pTerm, b->pTerm, n);
-  if( c!=0 ) return c;
-  return a->nTerm-b->nTerm;
-}
+struct RtreeNode {
+  RtreeNode *pParent;               /* Parent node */
+  i64 iNode;
+  int nRef;
+  int isDirty;
+  u8 *zData;
+  RtreeNode *pNext;                 /* Next node in this hash chain */
+};
+#define NCELL(pNode) readInt16(&(pNode)->zData[2])
 
-/* Order pTerms data by term, then write a new level 0 segment using
-** LeafWriter.
+/* 
+** Structure to store a deserialized rtree record.
 */
-static int writeZeroSegment(fulltext_vtab *v, fts3Hash *pTerms){
-  fts3HashElem *e;
-  int idx, rc, i, n;
-  TermData *pData;
-  LeafWriter writer;
-  DataBuffer dl;
+struct RtreeCell {
+  i64 iRowid;
+  RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];
+};
 
-  /* Determine the next index at level 0, merging as necessary. */
-  rc = segdirNextIndex(v, 0, &idx);
-  if( rc!=SQLITE_OK ) return rc;
+#ifndef MAX
+# define MAX(x,y) ((x) < (y) ? (y) : (x))
+#endif
+#ifndef MIN
+# define MIN(x,y) ((x) > (y) ? (y) : (x))
+#endif
 
-  n = fts3HashCount(pTerms);
-  pData = sqlite3_malloc(n*sizeof(TermData));
+/*
+** Functions to deserialize a 16 bit integer, 32 bit real number and
+** 64 bit integer. The deserialized value is returned.
+*/
+static int readInt16(u8 *p){
+  return (p[0]<<8) + p[1];
+}
+static void readCoord(u8 *p, RtreeCoord *pCoord){
+  u32 i = (
+    (((u32)p[0]) << 24) + 
+    (((u32)p[1]) << 16) + 
+    (((u32)p[2]) <<  8) + 
+    (((u32)p[3]) <<  0)
+  );
+  *(u32 *)pCoord = i;
+}
+static i64 readInt64(u8 *p){
+  return (
+    (((i64)p[0]) << 56) + 
+    (((i64)p[1]) << 48) + 
+    (((i64)p[2]) << 40) + 
+    (((i64)p[3]) << 32) + 
+    (((i64)p[4]) << 24) + 
+    (((i64)p[5]) << 16) + 
+    (((i64)p[6]) <<  8) + 
+    (((i64)p[7]) <<  0)
+  );
+}
 
-  for(i = 0, e = fts3HashFirst(pTerms); e; i++, e = fts3HashNext(e)){
-    assert( i<n );
-    pData[i].pTerm = fts3HashKey(e);
-    pData[i].nTerm = fts3HashKeysize(e);
-    pData[i].pCollector = fts3HashData(e);
+/*
+** Functions to serialize a 16 bit integer, 32 bit real number and
+** 64 bit integer. The value returned is the number of bytes written
+** to the argument buffer (always 2, 4 and 8 respectively).
+*/
+static int writeInt16(u8 *p, int i){
+  p[0] = (i>> 8)&0xFF;
+  p[1] = (i>> 0)&0xFF;
+  return 2;
+}
+static int writeCoord(u8 *p, RtreeCoord *pCoord){
+  u32 i;
+  assert( sizeof(RtreeCoord)==4 );
+  assert( sizeof(u32)==4 );
+  i = *(u32 *)pCoord;
+  p[0] = (i>>24)&0xFF;
+  p[1] = (i>>16)&0xFF;
+  p[2] = (i>> 8)&0xFF;
+  p[3] = (i>> 0)&0xFF;
+  return 4;
+}
+static int writeInt64(u8 *p, i64 i){
+  p[0] = (i>>56)&0xFF;
+  p[1] = (i>>48)&0xFF;
+  p[2] = (i>>40)&0xFF;
+  p[3] = (i>>32)&0xFF;
+  p[4] = (i>>24)&0xFF;
+  p[5] = (i>>16)&0xFF;
+  p[6] = (i>> 8)&0xFF;
+  p[7] = (i>> 0)&0xFF;
+  return 8;
+}
+
+/*
+** Increment the reference count of node p.
+*/
+static void nodeReference(RtreeNode *p){
+  if( p ){
+    p->nRef++;
   }
-  assert( i==n );
-
-  /* TODO(shess) Should we allow user-defined collation sequences,
-  ** here?  I think we only need that once we support prefix searches.
-  */
-  if( n>1 ) qsort(pData, n, sizeof(*pData), termDataCmp);
+}
 
-  /* TODO(shess) Refactor so that we can write directly to the segment
-  ** DataBuffer, as happens for segment merges.
-  */
-  leafWriterInit(0, idx, &writer);
-  dataBufferInit(&dl, 0);
-  for(i=0; i<n; i++){
-    dataBufferReset(&dl);
-    dlcAddDoclist(pData[i].pCollector, &dl);
-    rc = leafWriterStep(v, &writer,
-                        pData[i].pTerm, pData[i].nTerm, dl.pData, dl.nData);
-    if( rc!=SQLITE_OK ) goto err;
+/*
+** Clear the content of node p (set all bytes to 0x00).
+*/
+static void nodeZero(Rtree *pRtree, RtreeNode *p){
+  if( p ){
+    memset(&p->zData[2], 0, pRtree->iNodeSize-2);
+    p->isDirty = 1;
   }
-  rc = leafWriterFinalize(v, &writer);
+}
 
- err:
-  dataBufferDestroy(&dl);
-  sqlite3_free(pData);
-  leafWriterDestroy(&writer);
-  return rc;
+/*
+** Given a node number iNode, return the corresponding key to use
+** in the Rtree.aHash table.
+*/
+static int nodeHash(i64 iNode){
+  return (
+    (iNode>>56) ^ (iNode>>48) ^ (iNode>>40) ^ (iNode>>32) ^ 
+    (iNode>>24) ^ (iNode>>16) ^ (iNode>> 8) ^ (iNode>> 0)
+  ) % HASHSIZE;
 }
 
-/* If pendingTerms has data, free it. */
-static int clearPendingTerms(fulltext_vtab *v){
-  if( v->nPendingData>=0 ){
-    fts3HashElem *e;
-    for(e=fts3HashFirst(&v->pendingTerms); e; e=fts3HashNext(e)){
-      dlcDelete(fts3HashData(e));
-    }
-    fts3HashClear(&v->pendingTerms);
-    v->nPendingData = -1;
-  }
-  return SQLITE_OK;
+/*
+** Search the node hash table for node iNode. If found, return a pointer
+** to it. Otherwise, return 0.
+*/
+static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){
+  RtreeNode *p;
+  assert( iNode!=0 );
+  for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext);
+  return p;
 }
 
-/* If pendingTerms has data, flush it to a level-zero segment, and
-** free it.
+/*
+** Add node pNode to the node hash table.
 */
-static int flushPendingTerms(fulltext_vtab *v){
-  if( v->nPendingData>=0 ){
-    int rc = writeZeroSegment(v, &v->pendingTerms);
-    if( rc==SQLITE_OK ) clearPendingTerms(v);
-    return rc;
+static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){
+  if( pNode ){
+    int iHash;
+    assert( pNode->pNext==0 );
+    iHash = nodeHash(pNode->iNode);
+    pNode->pNext = pRtree->aHash[iHash];
+    pRtree->aHash[iHash] = pNode;
   }
-  return SQLITE_OK;
 }
 
-/* If pendingTerms is "too big", or docid is out of order, flush it.
-** Regardless, be certain that pendingTerms is initialized for use.
+/*
+** Remove node pNode from the node hash table.
 */
-static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid){
-  /* TODO(shess) Explore whether partially flushing the buffer on
-  ** forced-flush would provide better performance.  I suspect that if
-  ** we ordered the doclists by size and flushed the largest until the
-  ** buffer was half empty, that would let the less frequent terms
-  ** generate longer doclists.
-  */
-  if( iDocid<=v->iPrevDocid || v->nPendingData>kPendingThreshold ){
-    int rc = flushPendingTerms(v);
-    if( rc!=SQLITE_OK ) return rc;
+static void nodeHashDelete(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode **pp;
+  if( pNode->iNode!=0 ){
+    pp = &pRtree->aHash[nodeHash(pNode->iNode)];
+    for( ; (*pp)!=pNode; pp = &(*pp)->pNext){ assert(*pp); }
+    *pp = pNode->pNext;
+    pNode->pNext = 0;
   }
-  if( v->nPendingData<0 ){
-    fts3HashInit(&v->pendingTerms, FTS3_HASH_STRING, 1);
-    v->nPendingData = 0;
+}
+
+/*
+** Allocate and return new r-tree node. Initially, (RtreeNode.iNode==0),
+** indicating that node has not yet been assigned a node number. It is
+** assigned a node number when nodeWrite() is called to write the
+** node contents out to the database.
+*/
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent, int zero){
+  RtreeNode *pNode;
+  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
+  if( pNode ){
+    memset(pNode, 0, sizeof(RtreeNode) + (zero?pRtree->iNodeSize:0));
+    pNode->zData = (u8 *)&pNode[1];
+    pNode->nRef = 1;
+    pNode->pParent = pParent;
+    pNode->isDirty = 1;
+    nodeReference(pParent);
   }
-  v->iPrevDocid = iDocid;
-  return SQLITE_OK;
+  return pNode;
 }
 
-/* This function implements the xUpdate callback; it is the top-level entry
- * point for inserting, deleting or updating a row in a full-text table. */
-static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg,
-                          sqlite_int64 *pRowid){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+/*
+** Obtain a reference to an r-tree node.
+*/
+static int
+nodeAcquire(
+  Rtree *pRtree,             /* R-tree structure */
+  i64 iNode,                 /* Node number to load */
+  RtreeNode *pParent,        /* Either the parent node or NULL */
+  RtreeNode **ppNode         /* OUT: Acquired node */
+){
   int rc;
+  RtreeNode *pNode;
 
-  FTSTRACE(("FTS3 Update %p\n", pVtab));
-
-  if( nArg<2 ){
-    rc = index_delete(v, sqlite3_value_int64(ppArg[0]));
-  } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){
-    /* An update:
-     * ppArg[0] = old rowid
-     * ppArg[1] = new rowid
-     * ppArg[2..2+v->nColumn-1] = values
-     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
-     * ppArg[2+v->nColumn+1] = value for docid
-     */
-    sqlite_int64 rowid = sqlite3_value_int64(ppArg[0]);
-    if( sqlite3_value_type(ppArg[1]) != SQLITE_INTEGER ||
-        sqlite3_value_int64(ppArg[1]) != rowid ){
-      rc = SQLITE_ERROR;  /* we don't allow changing the rowid */
-    }else if( sqlite3_value_type(ppArg[2+v->nColumn+1]) != SQLITE_INTEGER ||
-              sqlite3_value_int64(ppArg[2+v->nColumn+1]) != rowid ){
-      rc = SQLITE_ERROR;  /* we don't allow changing the docid */
-    }else{
-      assert( nArg==2+v->nColumn+2);
-      rc = index_update(v, rowid, &ppArg[2]);
-    }
-  } else {
-    /* An insert:
-     * ppArg[1] = requested rowid
-     * ppArg[2..2+v->nColumn-1] = values
-     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
-     * ppArg[2+v->nColumn+1] = value for docid
-     */
-    sqlite3_value *pRequestDocid = ppArg[2+v->nColumn+1];
-    assert( nArg==2+v->nColumn+2);
-    if( SQLITE_NULL != sqlite3_value_type(pRequestDocid) &&
-        SQLITE_NULL != sqlite3_value_type(ppArg[1]) ){
-      /* TODO(shess) Consider allowing this to work if the values are
-      ** identical.  I'm inclined to discourage that usage, though,
-      ** given that both rowid and docid are special columns.  Better
-      ** would be to define one or the other as the default winner,
-      ** but should it be fts3-centric (docid) or SQLite-centric
-      ** (rowid)?
-      */
-      rc = SQLITE_ERROR;
-    }else{
-      if( SQLITE_NULL == sqlite3_value_type(pRequestDocid) ){
-        pRequestDocid = ppArg[1];
-      }
-      rc = index_insert(v, pRequestDocid, &ppArg[2], pRowid);
+  /* Check if the requested node is already in the hash table. If so,
+  ** increase its reference count and return it.
+  */
+  if( (pNode = nodeHashLookup(pRtree, iNode)) ){
+    assert( !pParent || !pNode->pParent || pNode->pParent==pParent );
+    if( pParent && !pNode->pParent ){
+      nodeReference(pParent);
+      pNode->pParent = pParent;
     }
+    pNode->nRef++;
+    *ppNode = pNode;
+    return SQLITE_OK;
+  }
+
+  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
+  if( !pNode ){
+    *ppNode = 0;
+    return SQLITE_NOMEM;
   }
+  pNode->pParent = pParent;
+  pNode->zData = (u8 *)&pNode[1];
+  pNode->nRef = 1;
+  pNode->iNode = iNode;
+  pNode->isDirty = 0;
+  pNode->pNext = 0;
+
+  sqlite3_bind_int64(pRtree->pReadNode, 1, iNode);
+  rc = sqlite3_step(pRtree->pReadNode);
+  if( rc==SQLITE_ROW ){
+    const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0);
+    memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
+    nodeReference(pParent);
+  }else{
+    sqlite3_free(pNode);
+    pNode = 0;
+  }
+
+  *ppNode = pNode;
+  rc = sqlite3_reset(pRtree->pReadNode);
+
+  if( rc==SQLITE_OK && iNode==1 ){
+    pRtree->iDepth = readInt16(pNode->zData);
+  }
+
+  assert( (rc==SQLITE_OK && pNode) || (pNode==0 && rc!=SQLITE_OK) );
+  nodeHashInsert(pRtree, pNode);
 
   return rc;
 }
 
-static int fulltextSync(sqlite3_vtab *pVtab){
-  FTSTRACE(("FTS3 xSync()\n"));
-  return flushPendingTerms((fulltext_vtab *)pVtab);
+/*
+** Overwrite cell iCell of node pNode with the contents of pCell.
+*/
+static void nodeOverwriteCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode,  
+  RtreeCell *pCell, 
+  int iCell
+){
+  int ii;
+  u8 *p = &pNode->zData[4 + pRtree->nBytesPerCell*iCell];
+  p += writeInt64(p, pCell->iRowid);
+  for(ii=0; ii<(pRtree->nDim*2); ii++){
+    p += writeCoord(p, &pCell->aCoord[ii]);
+  }
+  pNode->isDirty = 1;
 }
 
-static int fulltextBegin(sqlite3_vtab *pVtab){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
-  FTSTRACE(("FTS3 xBegin()\n"));
-
-  /* Any buffered updates should have been cleared by the previous
-  ** transaction.
-  */
-  assert( v->nPendingData<0 );
-  return clearPendingTerms(v);
+/*
+** Remove cell the cell with index iCell from node pNode.
+*/
+static void nodeDeleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell){
+  u8 *pDst = &pNode->zData[4 + pRtree->nBytesPerCell*iCell];
+  u8 *pSrc = &pDst[pRtree->nBytesPerCell];
+  int nByte = (NCELL(pNode) - iCell - 1) * pRtree->nBytesPerCell;
+  memmove(pDst, pSrc, nByte);
+  writeInt16(&pNode->zData[2], NCELL(pNode)-1);
+  pNode->isDirty = 1;
 }
 
-static int fulltextCommit(sqlite3_vtab *pVtab){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
-  FTSTRACE(("FTS3 xCommit()\n"));
+/*
+** Insert the contents of cell pCell into node pNode. If the insert
+** is successful, return SQLITE_OK.
+**
+** If there is not enough free space in pNode, return SQLITE_FULL.
+*/
+static int
+nodeInsertCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  RtreeCell *pCell 
+){
+  int nCell;                    /* Current number of cells in pNode */
+  int nMaxCell;                 /* Maximum number of cells for pNode */
 
-  /* Buffered updates should have been cleared by fulltextSync(). */
-  assert( v->nPendingData<0 );
-  return clearPendingTerms(v);
+  nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell;
+  nCell = NCELL(pNode);
+
+  assert(nCell<=nMaxCell);
+
+  if( nCell<nMaxCell ){
+    nodeOverwriteCell(pRtree, pNode, pCell, nCell);
+    writeInt16(&pNode->zData[2], nCell+1);
+    pNode->isDirty = 1;
+  }
+
+  return (nCell==nMaxCell);
 }
 
-static int fulltextRollback(sqlite3_vtab *pVtab){
-  FTSTRACE(("FTS3 xRollback()\n"));
-  return clearPendingTerms((fulltext_vtab *)pVtab);
+/*
+** If the node is dirty, write it out to the database.
+*/
+static int
+nodeWrite(Rtree *pRtree, RtreeNode *pNode){
+  int rc = SQLITE_OK;
+  if( pNode->isDirty ){
+    sqlite3_stmt *p = pRtree->pWriteNode;
+    if( pNode->iNode ){
+      sqlite3_bind_int64(p, 1, pNode->iNode);
+    }else{
+      sqlite3_bind_null(p, 1);
+    }
+    sqlite3_bind_blob(p, 2, pNode->zData, pRtree->iNodeSize, SQLITE_STATIC);
+    sqlite3_step(p);
+    pNode->isDirty = 0;
+    rc = sqlite3_reset(p);
+    if( pNode->iNode==0 && rc==SQLITE_OK ){
+      pNode->iNode = sqlite3_last_insert_rowid(pRtree->db);
+      nodeHashInsert(pRtree, pNode);
+    }
+  }
+  return rc;
 }
 
 /*
-** Implementation of the snippet() function for FTS3
+** Release a reference to a node. If the node is dirty and the reference
+** count drops to zero, the node data is written to the database.
 */
-static void snippetFunc(
-  sqlite3_context *pContext,
-  int argc,
-  sqlite3_value **argv
-){
-  fulltext_cursor *pCursor;
-  if( argc<1 ) return;
-  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
-      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
-    sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1);
-  }else{
-    const char *zStart = "<b>";
-    const char *zEnd = "</b>";
-    const char *zEllipsis = "<b>...</b>";
-    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
-    if( argc>=2 ){
-      zStart = (const char*)sqlite3_value_text(argv[1]);
-      if( argc>=3 ){
-        zEnd = (const char*)sqlite3_value_text(argv[2]);
-        if( argc>=4 ){
-          zEllipsis = (const char*)sqlite3_value_text(argv[3]);
-        }
+static int
+nodeRelease(Rtree *pRtree, RtreeNode *pNode){
+  int rc = SQLITE_OK;
+  if( pNode ){
+    assert( pNode->nRef>0 );
+    pNode->nRef--;
+    if( pNode->nRef==0 ){
+      if( pNode->iNode==1 ){
+        pRtree->iDepth = -1;
       }
+      if( pNode->pParent ){
+        rc = nodeRelease(pRtree, pNode->pParent);
+      }
+      if( rc==SQLITE_OK ){
+        rc = nodeWrite(pRtree, pNode);
+      }
+      nodeHashDelete(pRtree, pNode);
+      sqlite3_free(pNode);
     }
-    snippetAllOffsets(pCursor);
-    snippetText(pCursor, zStart, zEnd, zEllipsis);
-    sqlite3_result_text(pContext, pCursor->snippet.zSnippet,
-                        pCursor->snippet.nSnippet, SQLITE_STATIC);
   }
+  return rc;
 }
 
 /*
-** Implementation of the offsets() function for FTS3
+** Return the 64-bit integer value associated with cell iCell of
+** node pNode. If pNode is a leaf node, this is a rowid. If it is
+** an internal node, then the 64-bit integer is a child page number.
 */
-static void snippetOffsetsFunc(
-  sqlite3_context *pContext,
-  int argc,
-  sqlite3_value **argv
+static i64 nodeGetRowid(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell
 ){
-  fulltext_cursor *pCursor;
-  if( argc<1 ) return;
-  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
-      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
-    sqlite3_result_error(pContext, "illegal first argument to offsets",-1);
-  }else{
-    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
-    snippetAllOffsets(pCursor);
-    snippetOffsetText(&pCursor->snippet);
-    sqlite3_result_text(pContext,
-                        pCursor->snippet.zOffset, pCursor->snippet.nOffset,
-                        SQLITE_STATIC);
-  }
+  assert( iCell<NCELL(pNode) );
+  return readInt64(&pNode->zData[4 + pRtree->nBytesPerCell*iCell]);
 }
 
 /*
-** This routine implements the xFindFunction method for the FTS3
-** virtual table.
+** Return coordinate iCoord from cell iCell in node pNode.
 */
-static int fulltextFindFunction(
-  sqlite3_vtab *pVtab,
-  int nArg,
-  const char *zName,
-  void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
-  void **ppArg
+static void nodeGetCoord(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell,
+  int iCoord,
+  RtreeCoord *pCoord           /* Space to write result to */
 ){
-  if( strcmp(zName,"snippet")==0 ){
-    *pxFunc = snippetFunc;
-    return 1;
-  }else if( strcmp(zName,"offsets")==0 ){
-    *pxFunc = snippetOffsetsFunc;
-    return 1;
-  }
-  return 0;
+  readCoord(&pNode->zData[12 + pRtree->nBytesPerCell*iCell + 4*iCoord], pCoord);
 }
 
 /*
-** Rename an fts3 table.
+** Deserialize cell iCell of node pNode. Populate the structure pointed
+** to by pCell with the results.
 */
-static int fulltextRename(
-  sqlite3_vtab *pVtab,
-  const char *zName
+static void nodeGetCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell,
+  RtreeCell *pCell
 ){
-  fulltext_vtab *p = (fulltext_vtab *)pVtab;
-  int rc = SQLITE_NOMEM;
-  char *zSql = sqlite3_mprintf(
-    "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';"
-    "ALTER TABLE %Q.'%q_segments' RENAME TO '%q_segments';"
-    "ALTER TABLE %Q.'%q_segdir'   RENAME TO '%q_segdir';"
-    , p->zDb, p->zName, zName 
-    , p->zDb, p->zName, zName 
-    , p->zDb, p->zName, zName
-  );
-  if( zSql ){
-    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
-    sqlite3_free(zSql);
+  int ii;
+  pCell->iRowid = nodeGetRowid(pRtree, pNode, iCell);
+  for(ii=0; ii<pRtree->nDim*2; ii++){
+    nodeGetCoord(pRtree, pNode, iCell, ii, &pCell->aCoord[ii]);
   }
-  return rc;
 }
 
-static const sqlite3_module fts3Module = {
-  /* iVersion      */ 0,
-  /* xCreate       */ fulltextCreate,
-  /* xConnect      */ fulltextConnect,
-  /* xBestIndex    */ fulltextBestIndex,
-  /* xDisconnect   */ fulltextDisconnect,
-  /* xDestroy      */ fulltextDestroy,
-  /* xOpen         */ fulltextOpen,
-  /* xClose        */ fulltextClose,
-  /* xFilter       */ fulltextFilter,
-  /* xNext         */ fulltextNext,
-  /* xEof          */ fulltextEof,
-  /* xColumn       */ fulltextColumn,
-  /* xRowid        */ fulltextRowid,
-  /* xUpdate       */ fulltextUpdate,
-  /* xBegin        */ fulltextBegin,
-  /* xSync         */ fulltextSync,
-  /* xCommit       */ fulltextCommit,
-  /* xRollback     */ fulltextRollback,
-  /* xFindFunction */ fulltextFindFunction,
-  /* xRename */       fulltextRename,
-};
 
-static void hashDestroy(void *p){
-  fts3Hash *pHash = (fts3Hash *)p;
-  sqlite3Fts3HashClear(pHash);
-  sqlite3_free(pHash);
+/* Forward declaration for the function that does the work of
+** the virtual table module xCreate() and xConnect() methods.
+*/
+static int rtreeInit(
+  sqlite3 *, void *, int, const char *const*, sqlite3_vtab **, char **, int
+);
+
+/* 
+** Rtree virtual table module xCreate method.
+*/
+static int rtreeCreate(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 1);
 }
 
-/*
-** The fts3 built-in tokenizers - "simple" and "porter" - are implemented
-** in files fts3_tokenizer1.c and fts3_porter.c respectively. The following
-** two forward declarations are for functions declared in these files
-** used to retrieve the respective implementations.
-**
-** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
-** to by the argument to point a the "simple" tokenizer implementation.
-** Function ...PorterTokenizerModule() sets *pModule to point to the
-** porter tokenizer/stemmer implementation.
+/* 
+** Rtree virtual table module xConnect method.
 */
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+static int rtreeConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 0);
+}
 
-SQLITE_PRIVATE int sqlite3Fts3InitHashTable(sqlite3 *, fts3Hash *, const char *);
+/*
+** Increment the r-tree reference count.
+*/
+static void rtreeReference(Rtree *pRtree){
+  pRtree->nBusy++;
+}
 
 /*
-** Initialise the fts3 extension. If this extension is built as part
-** of the sqlite library, then this function is called directly by
-** SQLite. If fts3 is built as a dynamically loadable extension, this
-** function is called by the sqlite3_extension_init() entry point.
+** Decrement the r-tree reference count. When the reference count reaches
+** zero the structure is deleted.
 */
-SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
-  int rc = SQLITE_OK;
-  fts3Hash *pHash = 0;
-  const sqlite3_tokenizer_module *pSimple = 0;
-  const sqlite3_tokenizer_module *pPorter = 0;
-  const sqlite3_tokenizer_module *pIcu = 0;
+static void rtreeRelease(Rtree *pRtree){
+  pRtree->nBusy--;
+  if( pRtree->nBusy==0 ){
+    sqlite3_finalize(pRtree->pReadNode);
+    sqlite3_finalize(pRtree->pWriteNode);
+    sqlite3_finalize(pRtree->pDeleteNode);
+    sqlite3_finalize(pRtree->pReadRowid);
+    sqlite3_finalize(pRtree->pWriteRowid);
+    sqlite3_finalize(pRtree->pDeleteRowid);
+    sqlite3_finalize(pRtree->pReadParent);
+    sqlite3_finalize(pRtree->pWriteParent);
+    sqlite3_finalize(pRtree->pDeleteParent);
+    sqlite3_free(pRtree);
+  }
+}
 
-  sqlite3Fts3SimpleTokenizerModule(&pSimple);
-  sqlite3Fts3PorterTokenizerModule(&pPorter);
-#ifdef SQLITE_ENABLE_ICU
-  sqlite3Fts3IcuTokenizerModule(&pIcu);
-#endif
+/* 
+** Rtree virtual table module xDisconnect method.
+*/
+static int rtreeDisconnect(sqlite3_vtab *pVtab){
+  rtreeRelease((Rtree *)pVtab);
+  return SQLITE_OK;
+}
 
-  /* Allocate and initialise the hash-table used to store tokenizers. */
-  pHash = sqlite3_malloc(sizeof(fts3Hash));
-  if( !pHash ){
+/* 
+** Rtree virtual table module xDestroy method.
+*/
+static int rtreeDestroy(sqlite3_vtab *pVtab){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc;
+  char *zCreate = sqlite3_mprintf(
+    "DROP TABLE '%q'.'%q_node';"
+    "DROP TABLE '%q'.'%q_rowid';"
+    "DROP TABLE '%q'.'%q_parent';",
+    pRtree->zDb, pRtree->zName, 
+    pRtree->zDb, pRtree->zName,
+    pRtree->zDb, pRtree->zName
+  );
+  if( !zCreate ){
     rc = SQLITE_NOMEM;
   }else{
-    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
+    rc = sqlite3_exec(pRtree->db, zCreate, 0, 0, 0);
+    sqlite3_free(zCreate);
   }
-
-  /* Load the built-in tokenizers into the hash table */
   if( rc==SQLITE_OK ){
-    if( sqlite3Fts3HashInsert(pHash, "simple", 7, (void *)pSimple)
-     || sqlite3Fts3HashInsert(pHash, "porter", 7, (void *)pPorter) 
-     || (pIcu && sqlite3Fts3HashInsert(pHash, "icu", 4, (void *)pIcu))
-    ){
-      rc = SQLITE_NOMEM;
-    }
+    rtreeRelease(pRtree);
   }
 
-  /* Create the virtual table wrapper around the hash-table and overload 
-  ** the two scalar functions. If this is successful, register the
-  ** module with sqlite.
-  */
-  if( SQLITE_OK==rc 
-   && SQLITE_OK==(rc = sqlite3Fts3InitHashTable(db, pHash, "fts3_tokenizer"))
-   && SQLITE_OK==(rc = sqlite3_overload_function(db, "snippet", -1))
-   && SQLITE_OK==(rc = sqlite3_overload_function(db, "offsets", -1))
-  ){
-    return sqlite3_create_module_v2(
-        db, "fts3", &fts3Module, (void *)pHash, hashDestroy
-    );
-  }
+  return rc;
+}
 
-  /* An error has occured. Delete the hash table and return the error code. */
-  assert( rc!=SQLITE_OK );
-  if( pHash ){
-    sqlite3Fts3HashClear(pHash);
-    sqlite3_free(pHash);
+/* 
+** Rtree virtual table module xOpen method.
+*/
+static int rtreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  int rc = SQLITE_NOMEM;
+  RtreeCursor *pCsr;
+
+  pCsr = (RtreeCursor *)sqlite3_malloc(sizeof(RtreeCursor));
+  if( pCsr ){
+    memset(pCsr, 0, sizeof(RtreeCursor));
+    pCsr->base.pVtab = pVTab;
+    rc = SQLITE_OK;
   }
+  *ppCursor = (sqlite3_vtab_cursor *)pCsr;
+
   return rc;
 }
 
-#if !SQLITE_CORE
-SQLITE_API int sqlite3_extension_init(
-  sqlite3 *db, 
-  char **pzErrMsg,
-  const sqlite3_api_routines *pApi
-){
-  SQLITE_EXTENSION_INIT2(pApi)
-  return sqlite3Fts3Init(db);
+/* 
+** Rtree virtual table module xClose method.
+*/
+static int rtreeClose(sqlite3_vtab_cursor *cur){
+  Rtree *pRtree = (Rtree *)(cur->pVtab);
+  int rc;
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+  sqlite3_free(pCsr->aConstraint);
+  rc = nodeRelease(pRtree, pCsr->pNode);
+  sqlite3_free(pCsr);
+  return rc;
 }
-#endif
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
-
-/************** End of fts3.c ************************************************/
-/************** Begin file fts3_hash.c ***************************************/
 /*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Rtree virtual table module xEof method.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the implementation of generic hash-tables used in SQLite.
-** We've modified it slightly to serve as a standalone hash table
-** implementation for the full-text indexing module.
+** Return non-zero if the cursor does not currently point to a valid 
+** record (i.e if the scan has finished), or zero otherwise.
 */
+static int rtreeEof(sqlite3_vtab_cursor *cur){
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+  return (pCsr->pNode==0);
+}
 
-/*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+/* 
+** Cursor pCursor currently points to a cell in a non-leaf page.
+** Return true if the sub-tree headed by the cell is filtered
+** (excluded) by the constraints in the pCursor->aConstraint[] 
+** array, or false otherwise.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
+  RtreeCell cell;
+  int ii;
+  int bRes = 0;
 
+  nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
+  for(ii=0; bRes==0 && ii<pCursor->nConstraint; ii++){
+    RtreeConstraint *p = &pCursor->aConstraint[ii];
+    double cell_min = DCOORD(cell.aCoord[(p->iCoord>>1)*2]);
+    double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
 
+    assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
+        || p->op==RTREE_GT || p->op==RTREE_EQ
+    );
 
-/*
-** Malloc and Free functions
-*/
-static void *fts3HashMalloc(int n){
-  void *p = sqlite3_malloc(n);
-  if( p ){
-    memset(p, 0, n);
+    switch( p->op ){
+      case RTREE_LE: case RTREE_LT: bRes = p->rValue<cell_min; break;
+      case RTREE_GE: case RTREE_GT: bRes = p->rValue>cell_max; break;
+      case RTREE_EQ: 
+        bRes = (p->rValue>cell_max || p->rValue<cell_min);
+        break;
+    }
   }
-  return p;
-}
-static void fts3HashFree(void *p){
-  sqlite3_free(p);
+
+  return bRes;
 }
 
-/* Turn bulk memory into a hash table object by initializing the
-** fields of the Hash structure.
+/* 
+** Return true if the cell that cursor pCursor currently points to
+** would be filtered (excluded) by the constraints in the 
+** pCursor->aConstraint[] array, or false otherwise.
 **
-** "pNew" is a pointer to the hash table that is to be initialized.
-** keyClass is one of the constants 
-** FTS3_HASH_BINARY or FTS3_HASH_STRING.  The value of keyClass 
-** determines what kind of key the hash table will use.  "copyKey" is
-** true if the hash table should make its own private copy of keys and
-** false if it should just use the supplied pointer.
+** This function assumes that the cell is part of a leaf node.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash *pNew, int keyClass, int copyKey){
-  assert( pNew!=0 );
-  assert( keyClass>=FTS3_HASH_STRING && keyClass<=FTS3_HASH_BINARY );
-  pNew->keyClass = keyClass;
-  pNew->copyKey = copyKey;
-  pNew->first = 0;
-  pNew->count = 0;
-  pNew->htsize = 0;
-  pNew->ht = 0;
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
+  RtreeCell cell;
+  int ii;
+
+  nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
+  for(ii=0; ii<pCursor->nConstraint; ii++){
+    RtreeConstraint *p = &pCursor->aConstraint[ii];
+    double coord = DCOORD(cell.aCoord[p->iCoord]);
+    int res;
+    assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
+        || p->op==RTREE_GT || p->op==RTREE_EQ
+    );
+    switch( p->op ){
+      case RTREE_LE: res = (coord<=p->rValue); break;
+      case RTREE_LT: res = (coord<p->rValue);  break;
+      case RTREE_GE: res = (coord>=p->rValue); break;
+      case RTREE_GT: res = (coord>p->rValue);  break;
+      case RTREE_EQ: res = (coord==p->rValue); break;
+    }
+
+    if( !res ) return 1;
+  }
+
+  return 0;
 }
 
-/* Remove all entries from a hash table.  Reclaim all memory.
-** Call this routine to delete a hash table or to reset a hash table
-** to the empty state.
+/*
+** Cursor pCursor currently points at a node that heads a sub-tree of
+** height iHeight (if iHeight==0, then the node is a leaf). Descend
+** to point to the left-most cell of the sub-tree that matches the 
+** configured constraints.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash *pH){
-  fts3HashElem *elem;         /* For looping over all elements of the table */
+static int descendToCell(
+  Rtree *pRtree, 
+  RtreeCursor *pCursor, 
+  int iHeight,
+  int *pEof                 /* OUT: Set to true if cannot descend */
+){
+  int isEof;
+  int rc;
+  int ii;
+  RtreeNode *pChild;
+  sqlite3_int64 iRowid;
 
-  assert( pH!=0 );
-  elem = pH->first;
-  pH->first = 0;
-  fts3HashFree(pH->ht);
-  pH->ht = 0;
-  pH->htsize = 0;
-  while( elem ){
-    fts3HashElem *next_elem = elem->next;
-    if( pH->copyKey && elem->pKey ){
-      fts3HashFree(elem->pKey);
+  RtreeNode *pSavedNode = pCursor->pNode;
+  int iSavedCell = pCursor->iCell;
+
+  assert( iHeight>=0 );
+
+  if( iHeight==0 ){
+    isEof = testRtreeEntry(pRtree, pCursor);
+  }else{
+    isEof = testRtreeCell(pRtree, pCursor);
+  }
+  if( isEof || iHeight==0 ){
+    *pEof = isEof;
+    return SQLITE_OK;
+  }
+
+  iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
+  rc = nodeAcquire(pRtree, iRowid, pCursor->pNode, &pChild);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
+  nodeRelease(pRtree, pCursor->pNode);
+  pCursor->pNode = pChild;
+  isEof = 1;
+  for(ii=0; isEof && ii<NCELL(pChild); ii++){
+    pCursor->iCell = ii;
+    rc = descendToCell(pRtree, pCursor, iHeight-1, &isEof);
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
-    fts3HashFree(elem);
-    elem = next_elem;
   }
-  pH->count = 0;
+
+  if( isEof ){
+    assert( pCursor->pNode==pChild );
+    nodeReference(pSavedNode);
+    nodeRelease(pRtree, pChild);
+    pCursor->pNode = pSavedNode;
+    pCursor->iCell = iSavedCell;
+  }
+
+  *pEof = isEof;
+  return SQLITE_OK;
 }
 
 /*
-** Hash and comparison functions when the mode is FTS3_HASH_STRING
+** One of the cells in node pNode is guaranteed to have a 64-bit 
+** integer value equal to iRowid. Return the index of this cell.
 */
-static int fts3StrHash(const void *pKey, int nKey){
-  const char *z = (const char *)pKey;
-  int h = 0;
-  if( nKey<=0 ) nKey = (int) strlen(z);
-  while( nKey > 0  ){
-    h = (h<<3) ^ h ^ *z++;
-    nKey--;
+static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
+  int ii;
+  for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
+    assert( ii<(NCELL(pNode)-1) );
   }
-  return h & 0x7fffffff;
-}
-static int fts3StrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return strncmp((const char*)pKey1,(const char*)pKey2,n1);
+  return ii;
 }
 
 /*
-** Hash and comparison functions when the mode is FTS3_HASH_BINARY
+** Return the index of the cell containing a pointer to node pNode
+** in its parent. If pNode is the root node, return -1.
 */
-static int fts3BinHash(const void *pKey, int nKey){
-  int h = 0;
-  const char *z = (const char *)pKey;
-  while( nKey-- > 0 ){
-    h = (h<<3) ^ h ^ *(z++);
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode *pParent = pNode->pParent;
+  if( pParent ){
+    return nodeRowidIndex(pRtree, pParent, pNode->iNode);
   }
-  return h & 0x7fffffff;
-}
-static int fts3BinCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return memcmp(pKey1,pKey2,n1);
+  return -1;
 }
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** The C syntax in this function definition may be unfamilar to some 
-** programmers, so we provide the following additional explanation:
-**
-** The name of the function is "ftsHashFunction".  The function takes a
-** single parameter "keyClass".  The return value of ftsHashFunction()
-** is a pointer to another function.  Specifically, the return value
-** of ftsHashFunction() is a pointer to a function that takes two parameters
-** with types "const void*" and "int" and returns an "int".
+/* 
+** Rtree virtual table module xNext method.
 */
-static int (*ftsHashFunction(int keyClass))(const void*,int){
-  if( keyClass==FTS3_HASH_STRING ){
-    return &fts3StrHash;
-  }else{
-    assert( keyClass==FTS3_HASH_BINARY );
-    return &fts3BinHash;
+static int rtreeNext(sqlite3_vtab_cursor *pVtabCursor){
+  Rtree *pRtree = (Rtree *)(pVtabCursor->pVtab);
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
+  int rc = SQLITE_OK;
+
+  if( pCsr->iStrategy==1 ){
+    /* This "scan" is a direct lookup by rowid. There is no next entry. */
+    nodeRelease(pRtree, pCsr->pNode);
+    pCsr->pNode = 0;
+  }
+
+  else if( pCsr->pNode ){
+    /* Move to the next entry that matches the configured constraints. */
+    int iHeight = 0;
+    while( pCsr->pNode ){
+      RtreeNode *pNode = pCsr->pNode;
+      int nCell = NCELL(pNode);
+      for(pCsr->iCell++; pCsr->iCell<nCell; pCsr->iCell++){
+        int isEof;
+        rc = descendToCell(pRtree, pCsr, iHeight, &isEof);
+        if( rc!=SQLITE_OK || !isEof ){
+          return rc;
+        }
+      }
+      pCsr->pNode = pNode->pParent;
+      pCsr->iCell = nodeParentIndex(pRtree, pNode);
+      nodeReference(pCsr->pNode);
+      nodeRelease(pRtree, pNode);
+      iHeight++;
+    }
   }
+
+  return rc;
 }
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** For help in interpreted the obscure C code in the function definition,
-** see the header comment on the previous function.
+/* 
+** Rtree virtual table module xRowid method.
 */
-static int (*ftsCompareFunction(int keyClass))(const void*,int,const void*,int){
-  if( keyClass==FTS3_HASH_STRING ){
-    return &fts3StrCompare;
+static int rtreeRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *pRowid){
+  Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
+
+  assert(pCsr->pNode);
+  *pRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
+
+  return SQLITE_OK;
+}
+
+/* 
+** Rtree virtual table module xColumn method.
+*/
+static int rtreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  Rtree *pRtree = (Rtree *)cur->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+
+  if( i==0 ){
+    i64 iRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
+    sqlite3_result_int64(ctx, iRowid);
   }else{
-    assert( keyClass==FTS3_HASH_BINARY );
-    return &fts3BinCompare;
+    RtreeCoord c;
+    nodeGetCoord(pRtree, pCsr->pNode, pCsr->iCell, i-1, &c);
+    if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+      sqlite3_result_double(ctx, c.f);
+    }else{
+      assert( pRtree->eCoordType==RTREE_COORD_INT32 );
+      sqlite3_result_int(ctx, c.i);
+    }
   }
+
+  return SQLITE_OK;
 }
 
-/* Link an element into the hash table
+/* 
+** Use nodeAcquire() to obtain the leaf node containing the record with 
+** rowid iRowid. If successful, set *ppLeaf to point to the node and
+** return SQLITE_OK. If there is no such record in the table, set
+** *ppLeaf to 0 and return SQLITE_OK. If an error occurs, set *ppLeaf
+** to zero and return an SQLite error code.
 */
-static void fts3HashInsertElement(
-  fts3Hash *pH,            /* The complete hash table */
-  struct _fts3ht *pEntry,  /* The entry into which pNew is inserted */
-  fts3HashElem *pNew       /* The element to be inserted */
-){
-  fts3HashElem *pHead;     /* First element already in pEntry */
-  pHead = pEntry->chain;
-  if( pHead ){
-    pNew->next = pHead;
-    pNew->prev = pHead->prev;
-    if( pHead->prev ){ pHead->prev->next = pNew; }
-    else             { pH->first = pNew; }
-    pHead->prev = pNew;
+static int findLeafNode(Rtree *pRtree, i64 iRowid, RtreeNode **ppLeaf){
+  int rc;
+  *ppLeaf = 0;
+  sqlite3_bind_int64(pRtree->pReadRowid, 1, iRowid);
+  if( sqlite3_step(pRtree->pReadRowid)==SQLITE_ROW ){
+    i64 iNode = sqlite3_column_int64(pRtree->pReadRowid, 0);
+    rc = nodeAcquire(pRtree, iNode, 0, ppLeaf);
+    sqlite3_reset(pRtree->pReadRowid);
   }else{
-    pNew->next = pH->first;
-    if( pH->first ){ pH->first->prev = pNew; }
-    pNew->prev = 0;
-    pH->first = pNew;
+    rc = sqlite3_reset(pRtree->pReadRowid);
   }
-  pEntry->count++;
-  pEntry->chain = pNew;
+  return rc;
 }
 
 
-/* Resize the hash table so that it cantains "new_size" buckets.
-** "new_size" must be a power of 2.  The hash table might fail 
-** to resize if sqliteMalloc() fails.
+/* 
+** Rtree virtual table module xFilter method.
 */
-static void fts3Rehash(fts3Hash *pH, int new_size){
-  struct _fts3ht *new_ht;          /* The new hash table */
-  fts3HashElem *elem, *next_elem;  /* For looping over existing elements */
-  int (*xHash)(const void*,int);   /* The hash function */
+static int rtreeFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
 
-  assert( (new_size & (new_size-1))==0 );
-  new_ht = (struct _fts3ht *)fts3HashMalloc( new_size*sizeof(struct _fts3ht) );
-  if( new_ht==0 ) return;
-  fts3HashFree(pH->ht);
-  pH->ht = new_ht;
-  pH->htsize = new_size;
-  xHash = ftsHashFunction(pH->keyClass);
-  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
-    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
-    next_elem = elem->next;
-    fts3HashInsertElement(pH, &new_ht[h], elem);
+  RtreeNode *pRoot = 0;
+  int ii;
+  int rc = SQLITE_OK;
+
+  rtreeReference(pRtree);
+
+  sqlite3_free(pCsr->aConstraint);
+  pCsr->aConstraint = 0;
+  pCsr->iStrategy = idxNum;
+
+  if( idxNum==1 ){
+    /* Special case - lookup by rowid. */
+    RtreeNode *pLeaf;        /* Leaf on which the required cell resides */
+    i64 iRowid = sqlite3_value_int64(argv[0]);
+    rc = findLeafNode(pRtree, iRowid, &pLeaf);
+    pCsr->pNode = pLeaf; 
+    if( pLeaf && rc==SQLITE_OK ){
+      pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
+    }
+  }else{
+    /* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array 
+    ** with the configured constraints. 
+    */
+    if( argc>0 ){
+      pCsr->aConstraint = sqlite3_malloc(sizeof(RtreeConstraint)*argc);
+      pCsr->nConstraint = argc;
+      if( !pCsr->aConstraint ){
+        rc = SQLITE_NOMEM;
+      }else{
+        assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
+        for(ii=0; ii<argc; ii++){
+          RtreeConstraint *p = &pCsr->aConstraint[ii];
+          p->op = idxStr[ii*2];
+          p->iCoord = idxStr[ii*2+1]-'a';
+          p->rValue = sqlite3_value_double(argv[ii]);
+        }
+      }
+    }
+  
+    if( rc==SQLITE_OK ){
+      pCsr->pNode = 0;
+      rc = nodeAcquire(pRtree, 1, 0, &pRoot);
+    }
+    if( rc==SQLITE_OK ){
+      int isEof = 1;
+      int nCell = NCELL(pRoot);
+      pCsr->pNode = pRoot;
+      for(pCsr->iCell=0; rc==SQLITE_OK && pCsr->iCell<nCell; pCsr->iCell++){
+        assert( pCsr->pNode==pRoot );
+        rc = descendToCell(pRtree, pCsr, pRtree->iDepth, &isEof);
+        if( !isEof ){
+          break;
+        }
+      }
+      if( rc==SQLITE_OK && isEof ){
+        assert( pCsr->pNode==pRoot );
+        nodeRelease(pRtree, pRoot);
+        pCsr->pNode = 0;
+      }
+      assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCell<NCELL(pCsr->pNode) );
+    }
   }
+
+  rtreeRelease(pRtree);
+  return rc;
 }
 
-/* This function (for internal use only) locates an element in an
-** hash table that matches the given key.  The hash for this key has
-** already been computed and is passed as the 4th parameter.
+/*
+** Rtree virtual table module xBestIndex method. There are three
+** table scan strategies to choose from (in order from most to 
+** least desirable):
+**
+**   idxNum     idxStr        Strategy
+**   ------------------------------------------------
+**     1        Unused        Direct lookup by rowid.
+**     2        See below     R-tree query.
+**     3        Unused        Full table scan.
+**   ------------------------------------------------
+**
+** If strategy 1 or 3 is used, then idxStr is not meaningful. If strategy
+** 2 is used, idxStr is formatted to contain 2 bytes for each 
+** constraint used. The first two bytes of idxStr correspond to 
+** the constraint in sqlite3_index_info.aConstraintUsage[] with
+** (argvIndex==1) etc.
+**
+** The first of each pair of bytes in idxStr identifies the constraint
+** operator as follows:
+**
+**   Operator    Byte Value
+**   ----------------------
+**      =        0x41 ('A')
+**     <=        0x42 ('B')
+**      <        0x43 ('C')
+**     >=        0x44 ('D')
+**      >        0x45 ('E')
+**   ----------------------
+**
+** The second of each pair of bytes identifies the coordinate column
+** to which the constraint applies. The leftmost coordinate column
+** is 'a', the second from the left 'b' etc.
 */
-static fts3HashElem *fts3FindElementByHash(
-  const fts3Hash *pH, /* The pH to be searched */
-  const void *pKey,   /* The key we are searching for */
-  int nKey,
-  int h               /* The hash for this key. */
-){
-  fts3HashElem *elem;            /* Used to loop thru the element list */
-  int count;                     /* Number of elements left to test */
-  int (*xCompare)(const void*,int,const void*,int);  /* comparison function */
+static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  int rc = SQLITE_OK;
+  int ii, cCol;
 
-  if( pH->ht ){
-    struct _fts3ht *pEntry = &pH->ht[h];
-    elem = pEntry->chain;
-    count = pEntry->count;
-    xCompare = ftsCompareFunction(pH->keyClass);
-    while( count-- && elem ){
-      if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
-        return elem;
+  int iIdx = 0;
+  char zIdxStr[RTREE_MAX_DIMENSIONS*8+1];
+  memset(zIdxStr, 0, sizeof(zIdxStr));
+
+  assert( pIdxInfo->idxStr==0 );
+  for(ii=0; ii<pIdxInfo->nConstraint; ii++){
+    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[ii];
+
+    if( p->usable && p->iColumn==0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+      /* We have an equality constraint on the rowid. Use strategy 1. */
+      int jj;
+      for(jj=0; jj<ii; jj++){
+        pIdxInfo->aConstraintUsage[jj].argvIndex = 0;
+        pIdxInfo->aConstraintUsage[jj].omit = 0;
+      }
+      pIdxInfo->idxNum = 1;
+      pIdxInfo->aConstraintUsage[ii].argvIndex = 1;
+      pIdxInfo->aConstraintUsage[jj].omit = 1;
+
+      /* This strategy involves a two rowid lookups on an B-Tree structures
+      ** and then a linear search of an R-Tree node. This should be 
+      ** considered almost as quick as a direct rowid lookup (for which 
+      ** sqlite uses an internal cost of 0.0).
+      */ 
+      pIdxInfo->estimatedCost = 10.0;
+      return SQLITE_OK;
+    }
+
+    if( p->usable && p->iColumn>0 ){
+      u8 op = 0;
+      switch( p->op ){
+        case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;
+        case SQLITE_INDEX_CONSTRAINT_GT: op = RTREE_GT; break;
+        case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break;
+        case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break;
+        case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break;
+      }
+      if( op ){
+        /* Make sure this particular constraint has not been used before.
+        ** If it has been used before, ignore it.
+        **
+        ** A <= or < can be used if there is a prior >= or >.
+        ** A >= or > can be used if there is a prior < or <=.
+        ** A <= or < is disqualified if there is a prior <=, <, or ==.
+        ** A >= or > is disqualified if there is a prior >=, >, or ==.
+        ** A == is disqualifed if there is any prior constraint.
+        */
+        int j, opmsk;
+        static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
+        assert( compatible[RTREE_EQ & 7]==0 );
+        assert( compatible[RTREE_LT & 7]==1 );
+        assert( compatible[RTREE_LE & 7]==1 );
+        assert( compatible[RTREE_GT & 7]==2 );
+        assert( compatible[RTREE_GE & 7]==2 );
+        cCol = p->iColumn - 1 + 'a';
+        opmsk = compatible[op & 7];
+        for(j=0; j<iIdx; j+=2){
+          if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
+            op = 0;
+            break;
+          }
+        }
+      }
+      if( op ){
+        assert( iIdx<sizeof(zIdxStr)-1 );
+        zIdxStr[iIdx++] = op;
+        zIdxStr[iIdx++] = cCol;
+        pIdxInfo->aConstraintUsage[ii].argvIndex = (iIdx/2);
+        pIdxInfo->aConstraintUsage[ii].omit = 1;
       }
-      elem = elem->next;
     }
   }
-  return 0;
+
+  pIdxInfo->idxNum = 2;
+  pIdxInfo->needToFreeIdxStr = 1;
+  if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){
+    return SQLITE_NOMEM;
+  }
+  assert( iIdx>=0 );
+  pIdxInfo->estimatedCost = (2000000.0 / (double)(iIdx + 1));
+  return rc;
 }
 
-/* Remove a single entry from the hash table given a pointer to that
-** element and a hash on the element's key.
+/*
+** Return the N-dimensional volumn of the cell stored in *p.
 */
-static void fts3RemoveElementByHash(
-  fts3Hash *pH,         /* The pH containing "elem" */
-  fts3HashElem* elem,   /* The element to be removed from the pH */
-  int h                 /* Hash value for the element */
-){
-  struct _fts3ht *pEntry;
-  if( elem->prev ){
-    elem->prev->next = elem->next; 
-  }else{
-    pH->first = elem->next;
-  }
-  if( elem->next ){
-    elem->next->prev = elem->prev;
-  }
-  pEntry = &pH->ht[h];
-  if( pEntry->chain==elem ){
-    pEntry->chain = elem->next;
+static float cellArea(Rtree *pRtree, RtreeCell *p){
+  float area = 1.0;
+  int ii;
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    area = area * (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii]));
   }
-  pEntry->count--;
-  if( pEntry->count<=0 ){
-    pEntry->chain = 0;
+  return area;
+}
+
+/*
+** Return the margin length of cell p. The margin length is the sum
+** of the objects size in each dimension.
+*/
+static float cellMargin(Rtree *pRtree, RtreeCell *p){
+  float margin = 0.0;
+  int ii;
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    margin += (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii]));
   }
-  if( pH->copyKey && elem->pKey ){
-    fts3HashFree(elem->pKey);
+  return margin;
+}
+
+/*
+** Store the union of cells p1 and p2 in p1.
+*/
+static void cellUnion(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){
+  int ii;
+  if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+    for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+      p1->aCoord[ii].f = MIN(p1->aCoord[ii].f, p2->aCoord[ii].f);
+      p1->aCoord[ii+1].f = MAX(p1->aCoord[ii+1].f, p2->aCoord[ii+1].f);
+    }
+  }else{
+    for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+      p1->aCoord[ii].i = MIN(p1->aCoord[ii].i, p2->aCoord[ii].i);
+      p1->aCoord[ii+1].i = MAX(p1->aCoord[ii+1].i, p2->aCoord[ii+1].i);
+    }
   }
-  fts3HashFree( elem );
-  pH->count--;
-  if( pH->count<=0 ){
-    assert( pH->first==0 );
-    assert( pH->count==0 );
-    fts3HashClear(pH);
+}
+
+/*
+** Return true if the area covered by p2 is a subset of the area covered
+** by p1. False otherwise.
+*/
+static int cellContains(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){
+  int ii;
+  int isInt = (pRtree->eCoordType==RTREE_COORD_INT32);
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    RtreeCoord *a1 = &p1->aCoord[ii];
+    RtreeCoord *a2 = &p2->aCoord[ii];
+    if( (!isInt && (a2[0].f<a1[0].f || a2[1].f>a1[1].f)) 
+     || ( isInt && (a2[0].i<a1[0].i || a2[1].i>a1[1].i)) 
+    ){
+      return 0;
+    }
   }
+  return 1;
 }
 
-/* Attempt to locate an element of the hash table pH with a key
-** that matches pKey,nKey.  Return the data for this element if it is
-** found, or NULL if there is no match.
+/*
+** Return the amount cell p would grow by if it were unioned with pCell.
 */
-SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash *pH, const void *pKey, int nKey){
-  int h;                 /* A hash on key */
-  fts3HashElem *elem;    /* The element that matches key */
-  int (*xHash)(const void*,int);  /* The hash function */
+static float cellGrowth(Rtree *pRtree, RtreeCell *p, RtreeCell *pCell){
+  float area;
+  RtreeCell cell;
+  memcpy(&cell, p, sizeof(RtreeCell));
+  area = cellArea(pRtree, &cell);
+  cellUnion(pRtree, &cell, pCell);
+  return (cellArea(pRtree, &cell)-area);
+}
 
-  if( pH==0 || pH->ht==0 ) return 0;
-  xHash = ftsHashFunction(pH->keyClass);
-  assert( xHash!=0 );
-  h = (*xHash)(pKey,nKey);
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  elem = fts3FindElementByHash(pH,pKey,nKey, h & (pH->htsize-1));
-  return elem ? elem->data : 0;
+#if VARIANT_RSTARTREE_CHOOSESUBTREE || VARIANT_RSTARTREE_SPLIT
+static float cellOverlap(
+  Rtree *pRtree, 
+  RtreeCell *p, 
+  RtreeCell *aCell, 
+  int nCell, 
+  int iExclude
+){
+  int ii;
+  float overlap = 0.0;
+  for(ii=0; ii<nCell; ii++){
+    if( ii!=iExclude ){
+      int jj;
+      float o = 1.0;
+      for(jj=0; jj<(pRtree->nDim*2); jj+=2){
+        double x1;
+        double x2;
+
+        x1 = MAX(DCOORD(p->aCoord[jj]), DCOORD(aCell[ii].aCoord[jj]));
+        x2 = MIN(DCOORD(p->aCoord[jj+1]), DCOORD(aCell[ii].aCoord[jj+1]));
+
+        if( x2<x1 ){
+          o = 0.0;
+          break;
+        }else{
+          o = o * (x2-x1);
+        }
+      }
+      overlap += o;
+    }
+  }
+  return overlap;
 }
+#endif
 
-/* Insert an element into the hash table pH.  The key is pKey,nKey
-** and the data is "data".
-**
-** If no element exists with a matching key, then a new
-** element is created.  A copy of the key is made if the copyKey
-** flag is set.  NULL is returned.
-**
-** If another element already exists with the same key, then the
-** new data replaces the old data and the old data is returned.
-** The key is not copied in this instance.  If a malloc fails, then
-** the new data is returned and the hash table is unchanged.
-**
-** If the "data" parameter to this function is NULL, then the
-** element corresponding to "key" is removed from the hash table.
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+static float cellOverlapEnlargement(
+  Rtree *pRtree, 
+  RtreeCell *p, 
+  RtreeCell *pInsert, 
+  RtreeCell *aCell, 
+  int nCell, 
+  int iExclude
+){
+  float before;
+  float after;
+  before = cellOverlap(pRtree, p, aCell, nCell, iExclude);
+  cellUnion(pRtree, p, pInsert);
+  after = cellOverlap(pRtree, p, aCell, nCell, iExclude);
+  return after-before;
+}
+#endif
+
+
+/*
+** This function implements the ChooseLeaf algorithm from Gutman[84].
+** ChooseSubTree in r*tree terminology.
 */
-SQLITE_PRIVATE void *sqlite3Fts3HashInsert(
-  fts3Hash *pH,        /* The hash table to insert into */
-  const void *pKey,    /* The key */
-  int nKey,            /* Number of bytes in the key */
-  void *data           /* The data */
+static int ChooseLeaf(
+  Rtree *pRtree,               /* Rtree table */
+  RtreeCell *pCell,            /* Cell to insert into rtree */
+  int iHeight,                 /* Height of sub-tree rooted at pCell */
+  RtreeNode **ppLeaf           /* OUT: Selected leaf page */
 ){
-  int hraw;                 /* Raw hash value of the key */
-  int h;                    /* the hash of the key modulo hash table size */
-  fts3HashElem *elem;       /* Used to loop thru the element list */
-  fts3HashElem *new_elem;   /* New element added to the pH */
-  int (*xHash)(const void*,int);  /* The hash function */
+  int rc;
+  int ii;
+  RtreeNode *pNode;
+  rc = nodeAcquire(pRtree, 1, 0, &pNode);
 
-  assert( pH!=0 );
-  xHash = ftsHashFunction(pH->keyClass);
-  assert( xHash!=0 );
-  hraw = (*xHash)(pKey, nKey);
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  h = hraw & (pH->htsize-1);
-  elem = fts3FindElementByHash(pH,pKey,nKey,h);
-  if( elem ){
-    void *old_data = elem->data;
-    if( data==0 ){
-      fts3RemoveElementByHash(pH,elem,h);
-    }else{
-      elem->data = data;
+  for(ii=0; rc==SQLITE_OK && ii<(pRtree->iDepth-iHeight); ii++){
+    int iCell;
+    sqlite3_int64 iBest;
+
+    float fMinGrowth;
+    float fMinArea;
+    float fMinOverlap;
+
+    int nCell = NCELL(pNode);
+    RtreeCell cell;
+    RtreeNode *pChild;
+
+    RtreeCell *aCell = 0;
+
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+    if( ii==(pRtree->iDepth-1) ){
+      int jj;
+      aCell = sqlite3_malloc(sizeof(RtreeCell)*nCell);
+      if( !aCell ){
+        rc = SQLITE_NOMEM;
+        nodeRelease(pRtree, pNode);
+        pNode = 0;
+        continue;
+      }
+      for(jj=0; jj<nCell; jj++){
+        nodeGetCell(pRtree, pNode, jj, &aCell[jj]);
+      }
     }
-    return old_data;
-  }
-  if( data==0 ) return 0;
-  new_elem = (fts3HashElem*)fts3HashMalloc( sizeof(fts3HashElem) );
-  if( new_elem==0 ) return data;
-  if( pH->copyKey && pKey!=0 ){
-    new_elem->pKey = fts3HashMalloc( nKey );
-    if( new_elem->pKey==0 ){
-      fts3HashFree(new_elem);
-      return data;
+#endif
+
+    /* Select the child node which will be enlarged the least if pCell
+    ** is inserted into it. Resolve ties by choosing the entry with
+    ** the smallest area.
+    */
+    for(iCell=0; iCell<nCell; iCell++){
+      float growth;
+      float area;
+      float overlap = 0.0;
+      nodeGetCell(pRtree, pNode, iCell, &cell);
+      growth = cellGrowth(pRtree, &cell, pCell);
+      area = cellArea(pRtree, &cell);
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+      if( ii==(pRtree->iDepth-1) ){
+        overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell);
+      }
+#endif
+      if( (iCell==0) 
+       || (overlap<fMinOverlap) 
+       || (overlap==fMinOverlap && growth<fMinGrowth)
+       || (overlap==fMinOverlap && growth==fMinGrowth && area<fMinArea)
+      ){
+        fMinOverlap = overlap;
+        fMinGrowth = growth;
+        fMinArea = area;
+        iBest = cell.iRowid;
+      }
     }
-    memcpy((void*)new_elem->pKey, pKey, nKey);
-  }else{
-    new_elem->pKey = (void*)pKey;
+
+    sqlite3_free(aCell);
+    rc = nodeAcquire(pRtree, iBest, pNode, &pChild);
+    nodeRelease(pRtree, pNode);
+    pNode = pChild;
   }
-  new_elem->nKey = nKey;
-  pH->count++;
-  if( pH->htsize==0 ){
-    fts3Rehash(pH,8);
-    if( pH->htsize==0 ){
-      pH->count = 0;
-      fts3HashFree(new_elem);
-      return data;
+
+  *ppLeaf = pNode;
+  return rc;
+}
+
+/*
+** A cell with the same content as pCell has just been inserted into
+** the node pNode. This function updates the bounding box cells in
+** all ancestor elements.
+*/
+static void AdjustTree(
+  Rtree *pRtree,                    /* Rtree table */
+  RtreeNode *pNode,                 /* Adjust ancestry of this node. */
+  RtreeCell *pCell                  /* This cell was just inserted */
+){
+  RtreeNode *p = pNode;
+  while( p->pParent ){
+    RtreeCell cell;
+    RtreeNode *pParent = p->pParent;
+    int iCell = nodeParentIndex(pRtree, p);
+
+    nodeGetCell(pRtree, pParent, iCell, &cell);
+    if( !cellContains(pRtree, &cell, pCell) ){
+      cellUnion(pRtree, &cell, pCell);
+      nodeOverwriteCell(pRtree, pParent, &cell, iCell);
     }
+ 
+    p = pParent;
   }
-  if( pH->count > pH->htsize ){
-    fts3Rehash(pH,pH->htsize*2);
-  }
-  assert( pH->htsize>0 );
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  h = hraw & (pH->htsize-1);
-  fts3HashInsertElement(pH, &pH->ht[h], new_elem);
-  new_elem->data = data;
-  return 0;
 }
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
-
-/************** End of fts3_hash.c *******************************************/
-/************** Begin file fts3_porter.c *************************************/
 /*
-** 2006 September 30
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** Implementation of the full-text-search tokenizer that implements
-** a Porter stemmer.
+** Write mapping (iRowid->iNode) to the <rtree>_rowid table.
 */
+static int rowidWrite(Rtree *pRtree, sqlite3_int64 iRowid, sqlite3_int64 iNode){
+  sqlite3_bind_int64(pRtree->pWriteRowid, 1, iRowid);
+  sqlite3_bind_int64(pRtree->pWriteRowid, 2, iNode);
+  sqlite3_step(pRtree->pWriteRowid);
+  return sqlite3_reset(pRtree->pWriteRowid);
+}
 
 /*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+** Write mapping (iNode->iPar) to the <rtree>_parent table.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+static int parentWrite(Rtree *pRtree, sqlite3_int64 iNode, sqlite3_int64 iPar){
+  sqlite3_bind_int64(pRtree->pWriteParent, 1, iNode);
+  sqlite3_bind_int64(pRtree->pWriteParent, 2, iPar);
+  sqlite3_step(pRtree->pWriteParent);
+  return sqlite3_reset(pRtree->pWriteParent);
+}
+
+static int rtreeInsertCell(Rtree *, RtreeNode *, RtreeCell *, int);
+
+#if VARIANT_GUTTMAN_LINEAR_SPLIT
+/*
+** Implementation of the linear variant of the PickNext() function from
+** Guttman[84].
+*/
+static RtreeCell *LinearPickNext(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  RtreeCell *pLeftBox, 
+  RtreeCell *pRightBox,
+  int *aiUsed
+){
+  int ii;
+  for(ii=0; aiUsed[ii]; ii++);
+  aiUsed[ii] = 1;
+  return &aCell[ii];
+}
+
+/*
+** Implementation of the linear variant of the PickSeeds() function from
+** Guttman[84].
+*/
+static void LinearPickSeeds(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  int *piLeftSeed, 
+  int *piRightSeed
+){
+  int i;
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  float maxNormalInnerWidth = 0.0;
+
+  /* Pick two "seed" cells from the array of cells. The algorithm used
+  ** here is the LinearPickSeeds algorithm from Gutman[1984]. The 
+  ** indices of the two seed cells in the array are stored in local
+  ** variables iLeftSeek and iRightSeed.
+  */
+  for(i=0; i<pRtree->nDim; i++){
+    float x1 = DCOORD(aCell[0].aCoord[i*2]);
+    float x2 = DCOORD(aCell[0].aCoord[i*2+1]);
+    float x3 = x1;
+    float x4 = x2;
+    int jj;
 
+    int iCellLeft = 0;
+    int iCellRight = 0;
 
+    for(jj=1; jj<nCell; jj++){
+      float left = DCOORD(aCell[jj].aCoord[i*2]);
+      float right = DCOORD(aCell[jj].aCoord[i*2+1]);
+
+      if( left<x1 ) x1 = left;
+      if( right>x4 ) x4 = right;
+      if( left>x3 ){
+        x3 = left;
+        iCellRight = jj;
+      }
+      if( right<x2 ){
+        x2 = right;
+        iCellLeft = jj;
+      }
+    }
+
+    if( x4!=x1 ){
+      float normalwidth = (x3 - x2) / (x4 - x1);
+      if( normalwidth>maxNormalInnerWidth ){
+        iLeftSeed = iCellLeft;
+        iRightSeed = iCellRight;
+      }
+    }
+  }
 
+  *piLeftSeed = iLeftSeed;
+  *piRightSeed = iRightSeed;
+}
+#endif /* VARIANT_GUTTMAN_LINEAR_SPLIT */
 
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT
 /*
-** Class derived from sqlite3_tokenizer
+** Implementation of the quadratic variant of the PickNext() function from
+** Guttman[84].
 */
-typedef struct porter_tokenizer {
-  sqlite3_tokenizer base;      /* Base class */
-} porter_tokenizer;
+static RtreeCell *QuadraticPickNext(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  RtreeCell *pLeftBox, 
+  RtreeCell *pRightBox,
+  int *aiUsed
+){
+  #define FABS(a) ((a)<0.0?-1.0*(a):(a))
+
+  int iSelect = -1;
+  float fDiff;
+  int ii;
+  for(ii=0; ii<nCell; ii++){
+    if( aiUsed[ii]==0 ){
+      float left = cellGrowth(pRtree, pLeftBox, &aCell[ii]);
+      float right = cellGrowth(pRtree, pLeftBox, &aCell[ii]);
+      float diff = FABS(right-left);
+      if( iSelect<0 || diff>fDiff ){
+        fDiff = diff;
+        iSelect = ii;
+      }
+    }
+  }
+  aiUsed[iSelect] = 1;
+  return &aCell[iSelect];
+}
 
 /*
-** Class derived from sqlit3_tokenizer_cursor
+** Implementation of the quadratic variant of the PickSeeds() function from
+** Guttman[84].
 */
-typedef struct porter_tokenizer_cursor {
-  sqlite3_tokenizer_cursor base;
-  const char *zInput;          /* input we are tokenizing */
-  int nInput;                  /* size of the input */
-  int iOffset;                 /* current position in zInput */
-  int iToken;                  /* index of next token to be returned */
-  char *zToken;                /* storage for current token */
-  int nAllocated;              /* space allocated to zToken buffer */
-} porter_tokenizer_cursor;
+static void QuadraticPickSeeds(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  int *piLeftSeed, 
+  int *piRightSeed
+){
+  int ii;
+  int jj;
 
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  float fWaste = 0.0;
 
-/* Forward declaration */
-static const sqlite3_tokenizer_module porterTokenizerModule;
+  for(ii=0; ii<nCell; ii++){
+    for(jj=ii+1; jj<nCell; jj++){
+      float right = cellArea(pRtree, &aCell[jj]);
+      float growth = cellGrowth(pRtree, &aCell[ii], &aCell[jj]);
+      float waste = growth - right;
+
+      if( waste>fWaste ){
+        iLeftSeed = ii;
+        iRightSeed = jj;
+        fWaste = waste;
+      }
+    }
+  }
 
+  *piLeftSeed = iLeftSeed;
+  *piRightSeed = iRightSeed;
+}
+#endif /* VARIANT_GUTTMAN_QUADRATIC_SPLIT */
 
 /*
-** Create a new tokenizer instance.
+** Arguments aIdx, aDistance and aSpare all point to arrays of size
+** nIdx. The aIdx array contains the set of integers from 0 to 
+** (nIdx-1) in no particular order. This function sorts the values
+** in aIdx according to the indexed values in aDistance. For
+** example, assuming the inputs:
+**
+**   aIdx      = { 0,   1,   2,   3 }
+**   aDistance = { 5.0, 2.0, 7.0, 6.0 }
+**
+** this function sets the aIdx array to contain:
+**
+**   aIdx      = { 0,   1,   2,   3 }
+**
+** The aSpare array is used as temporary working space by the
+** sorting algorithm.
 */
-static int porterCreate(
-  int argc, const char * const *argv,
-  sqlite3_tokenizer **ppTokenizer
+static void SortByDistance(
+  int *aIdx, 
+  int nIdx, 
+  float *aDistance, 
+  int *aSpare
 ){
-  porter_tokenizer *t;
-  t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
-  if( t==NULL ) return SQLITE_NOMEM;
-  memset(t, 0, sizeof(*t));
-  *ppTokenizer = &t->base;
-  return SQLITE_OK;
+  if( nIdx>1 ){
+    int iLeft = 0;
+    int iRight = 0;
+
+    int nLeft = nIdx/2;
+    int nRight = nIdx-nLeft;
+    int *aLeft = aIdx;
+    int *aRight = &aIdx[nLeft];
+
+    SortByDistance(aLeft, nLeft, aDistance, aSpare);
+    SortByDistance(aRight, nRight, aDistance, aSpare);
+
+    memcpy(aSpare, aLeft, sizeof(int)*nLeft);
+    aLeft = aSpare;
+
+    while( iLeft<nLeft || iRight<nRight ){
+      if( iLeft==nLeft ){
+        aIdx[iLeft+iRight] = aRight[iRight];
+        iRight++;
+      }else if( iRight==nRight ){
+        aIdx[iLeft+iRight] = aLeft[iLeft];
+        iLeft++;
+      }else{
+        float fLeft = aDistance[aLeft[iLeft]];
+        float fRight = aDistance[aRight[iRight]];
+        if( fLeft<fRight ){
+          aIdx[iLeft+iRight] = aLeft[iLeft];
+          iLeft++;
+        }else{
+          aIdx[iLeft+iRight] = aRight[iRight];
+          iRight++;
+        }
+      }
+    }
+
+#if 0
+    /* Check that the sort worked */
+    {
+      int jj;
+      for(jj=1; jj<nIdx; jj++){
+        float left = aDistance[aIdx[jj-1]];
+        float right = aDistance[aIdx[jj]];
+        assert( left<=right );
+      }
+    }
+#endif
+  }
 }
 
 /*
-** Destroy a tokenizer
+** Arguments aIdx, aCell and aSpare all point to arrays of size
+** nIdx. The aIdx array contains the set of integers from 0 to 
+** (nIdx-1) in no particular order. This function sorts the values
+** in aIdx according to dimension iDim of the cells in aCell. The
+** minimum value of dimension iDim is considered first, the
+** maximum used to break ties.
+**
+** The aSpare array is used as temporary working space by the
+** sorting algorithm.
 */
-static int porterDestroy(sqlite3_tokenizer *pTokenizer){
-  sqlite3_free(pTokenizer);
-  return SQLITE_OK;
+static void SortByDimension(
+  Rtree *pRtree,
+  int *aIdx, 
+  int nIdx, 
+  int iDim, 
+  RtreeCell *aCell, 
+  int *aSpare
+){
+  if( nIdx>1 ){
+
+    int iLeft = 0;
+    int iRight = 0;
+
+    int nLeft = nIdx/2;
+    int nRight = nIdx-nLeft;
+    int *aLeft = aIdx;
+    int *aRight = &aIdx[nLeft];
+
+    SortByDimension(pRtree, aLeft, nLeft, iDim, aCell, aSpare);
+    SortByDimension(pRtree, aRight, nRight, iDim, aCell, aSpare);
+
+    memcpy(aSpare, aLeft, sizeof(int)*nLeft);
+    aLeft = aSpare;
+    while( iLeft<nLeft || iRight<nRight ){
+      double xleft1 = DCOORD(aCell[aLeft[iLeft]].aCoord[iDim*2]);
+      double xleft2 = DCOORD(aCell[aLeft[iLeft]].aCoord[iDim*2+1]);
+      double xright1 = DCOORD(aCell[aRight[iRight]].aCoord[iDim*2]);
+      double xright2 = DCOORD(aCell[aRight[iRight]].aCoord[iDim*2+1]);
+      if( (iLeft!=nLeft) && ((iRight==nRight)
+       || (xleft1<xright1)
+       || (xleft1==xright1 && xleft2<xright2)
+      )){
+        aIdx[iLeft+iRight] = aLeft[iLeft];
+        iLeft++;
+      }else{
+        aIdx[iLeft+iRight] = aRight[iRight];
+        iRight++;
+      }
+    }
+
+#if 0
+    /* Check that the sort worked */
+    {
+      int jj;
+      for(jj=1; jj<nIdx; jj++){
+        float xleft1 = aCell[aIdx[jj-1]].aCoord[iDim*2];
+        float xleft2 = aCell[aIdx[jj-1]].aCoord[iDim*2+1];
+        float xright1 = aCell[aIdx[jj]].aCoord[iDim*2];
+        float xright2 = aCell[aIdx[jj]].aCoord[iDim*2+1];
+        assert( xleft1<=xright1 && (xleft1<xright1 || xleft2<=xright2) );
+      }
+    }
+#endif
+  }
 }
 
+#if VARIANT_RSTARTREE_SPLIT
 /*
-** Prepare to begin tokenizing a particular string.  The input
-** string to be tokenized is zInput[0..nInput-1].  A cursor
-** used to incrementally tokenize this string is returned in 
-** *ppCursor.
+** Implementation of the R*-tree variant of SplitNode from Beckman[1990].
 */
-static int porterOpen(
-  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
-  const char *zInput, int nInput,        /* String to be tokenized */
-  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
+static int splitNodeStartree(
+  Rtree *pRtree,
+  RtreeCell *aCell,
+  int nCell,
+  RtreeNode *pLeft,
+  RtreeNode *pRight,
+  RtreeCell *pBboxLeft,
+  RtreeCell *pBboxRight
 ){
-  porter_tokenizer_cursor *c;
+  int **aaSorted;
+  int *aSpare;
+  int ii;
 
-  c = (porter_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
-  if( c==NULL ) return SQLITE_NOMEM;
+  int iBestDim;
+  int iBestSplit;
+  float fBestMargin;
 
-  c->zInput = zInput;
-  if( zInput==0 ){
-    c->nInput = 0;
-  }else if( nInput<0 ){
-    c->nInput = (int)strlen(zInput);
-  }else{
-    c->nInput = nInput;
+  int nByte = (pRtree->nDim+1)*(sizeof(int*)+nCell*sizeof(int));
+
+  aaSorted = (int **)sqlite3_malloc(nByte);
+  if( !aaSorted ){
+    return SQLITE_NOMEM;
   }
-  c->iOffset = 0;                 /* start tokenizing at the beginning */
-  c->iToken = 0;
-  c->zToken = NULL;               /* no space allocated, yet. */
-  c->nAllocated = 0;
 
-  *ppCursor = &c->base;
+  aSpare = &((int *)&aaSorted[pRtree->nDim])[pRtree->nDim*nCell];
+  memset(aaSorted, 0, nByte);
+  for(ii=0; ii<pRtree->nDim; ii++){
+    int jj;
+    aaSorted[ii] = &((int *)&aaSorted[pRtree->nDim])[ii*nCell];
+    for(jj=0; jj<nCell; jj++){
+      aaSorted[ii][jj] = jj;
+    }
+    SortByDimension(pRtree, aaSorted[ii], nCell, ii, aCell, aSpare);
+  }
+
+  for(ii=0; ii<pRtree->nDim; ii++){
+    float margin = 0.0;
+    float fBestOverlap;
+    float fBestArea;
+    int iBestLeft;
+    int nLeft;
+
+    for(
+      nLeft=RTREE_MINCELLS(pRtree); 
+      nLeft<=(nCell-RTREE_MINCELLS(pRtree)); 
+      nLeft++
+    ){
+      RtreeCell left;
+      RtreeCell right;
+      int kk;
+      float overlap;
+      float area;
+
+      memcpy(&left, &aCell[aaSorted[ii][0]], sizeof(RtreeCell));
+      memcpy(&right, &aCell[aaSorted[ii][nCell-1]], sizeof(RtreeCell));
+      for(kk=1; kk<(nCell-1); kk++){
+        if( kk<nLeft ){
+          cellUnion(pRtree, &left, &aCell[aaSorted[ii][kk]]);
+        }else{
+          cellUnion(pRtree, &right, &aCell[aaSorted[ii][kk]]);
+        }
+      }
+      margin += cellMargin(pRtree, &left);
+      margin += cellMargin(pRtree, &right);
+      overlap = cellOverlap(pRtree, &left, &right, 1, -1);
+      area = cellArea(pRtree, &left) + cellArea(pRtree, &right);
+      if( (nLeft==RTREE_MINCELLS(pRtree))
+       || (overlap<fBestOverlap)
+       || (overlap==fBestOverlap && area<fBestArea)
+      ){
+        iBestLeft = nLeft;
+        fBestOverlap = overlap;
+        fBestArea = area;
+      }
+    }
+
+    if( ii==0 || margin<fBestMargin ){
+      iBestDim = ii;
+      fBestMargin = margin;
+      iBestSplit = iBestLeft;
+    }
+  }
+
+  memcpy(pBboxLeft, &aCell[aaSorted[iBestDim][0]], sizeof(RtreeCell));
+  memcpy(pBboxRight, &aCell[aaSorted[iBestDim][iBestSplit]], sizeof(RtreeCell));
+  for(ii=0; ii<nCell; ii++){
+    RtreeNode *pTarget = (ii<iBestSplit)?pLeft:pRight;
+    RtreeCell *pBbox = (ii<iBestSplit)?pBboxLeft:pBboxRight;
+    RtreeCell *pCell = &aCell[aaSorted[iBestDim][ii]];
+    nodeInsertCell(pRtree, pTarget, pCell);
+    cellUnion(pRtree, pBbox, pCell);
+  }
+
+  sqlite3_free(aaSorted);
   return SQLITE_OK;
 }
+#endif
 
+#if VARIANT_GUTTMAN_SPLIT
 /*
-** Close a tokenization cursor previously opened by a call to
-** porterOpen() above.
+** Implementation of the regular R-tree SplitNode from Guttman[1984].
 */
-static int porterClose(sqlite3_tokenizer_cursor *pCursor){
-  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
-  sqlite3_free(c->zToken);
-  sqlite3_free(c);
+static int splitNodeGuttman(
+  Rtree *pRtree,
+  RtreeCell *aCell,
+  int nCell,
+  RtreeNode *pLeft,
+  RtreeNode *pRight,
+  RtreeCell *pBboxLeft,
+  RtreeCell *pBboxRight
+){
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  int *aiUsed;
+  int i;
+
+  aiUsed = sqlite3_malloc(sizeof(int)*nCell);
+  if( !aiUsed ){
+    return SQLITE_NOMEM;
+  }
+  memset(aiUsed, 0, sizeof(int)*nCell);
+
+  PickSeeds(pRtree, aCell, nCell, &iLeftSeed, &iRightSeed);
+
+  memcpy(pBboxLeft, &aCell[iLeftSeed], sizeof(RtreeCell));
+  memcpy(pBboxRight, &aCell[iRightSeed], sizeof(RtreeCell));
+  nodeInsertCell(pRtree, pLeft, &aCell[iLeftSeed]);
+  nodeInsertCell(pRtree, pRight, &aCell[iRightSeed]);
+  aiUsed[iLeftSeed] = 1;
+  aiUsed[iRightSeed] = 1;
+
+  for(i=nCell-2; i>0; i--){
+    RtreeCell *pNext;
+    pNext = PickNext(pRtree, aCell, nCell, pBboxLeft, pBboxRight, aiUsed);
+    float diff =  
+      cellGrowth(pRtree, pBboxLeft, pNext) - 
+      cellGrowth(pRtree, pBboxRight, pNext)
+    ;
+    if( (RTREE_MINCELLS(pRtree)-NCELL(pRight)==i)
+     || (diff>0.0 && (RTREE_MINCELLS(pRtree)-NCELL(pLeft)!=i))
+    ){
+      nodeInsertCell(pRtree, pRight, pNext);
+      cellUnion(pRtree, pBboxRight, pNext);
+    }else{
+      nodeInsertCell(pRtree, pLeft, pNext);
+      cellUnion(pRtree, pBboxLeft, pNext);
+    }
+  }
+
+  sqlite3_free(aiUsed);
   return SQLITE_OK;
 }
-/*
-** Vowel or consonant
-*/
-static const char cType[] = {
-   0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,
-   1, 1, 1, 2, 1
-};
+#endif
 
-/*
-** isConsonant() and isVowel() determine if their first character in
-** the string they point to is a consonant or a vowel, according
-** to Porter ruls.  
-**
-** A consonate is any letter other than 'a', 'e', 'i', 'o', or 'u'.
-** 'Y' is a consonant unless it follows another consonant,
-** in which case it is a vowel.
-**
-** In these routine, the letters are in reverse order.  So the 'y' rule
-** is that 'y' is a consonant unless it is followed by another
-** consonent.
-*/
-static int isVowel(const char*);
-static int isConsonant(const char *z){
-  int j;
-  char x = *z;
-  if( x==0 ) return 0;
-  assert( x>='a' && x<='z' );
-  j = cType[x-'a'];
-  if( j<2 ) return j;
-  return z[1]==0 || isVowel(z + 1);
+static int updateMapping(
+  Rtree *pRtree, 
+  i64 iRowid, 
+  RtreeNode *pNode, 
+  int iHeight
+){
+  int (*xSetMapping)(Rtree *, sqlite3_int64, sqlite3_int64);
+  xSetMapping = ((iHeight==0)?rowidWrite:parentWrite);
+  if( iHeight>0 ){
+    RtreeNode *pChild = nodeHashLookup(pRtree, iRowid);
+    if( pChild ){
+      nodeRelease(pRtree, pChild->pParent);
+      nodeReference(pNode);
+      pChild->pParent = pNode;
+    }
+  }
+  return xSetMapping(pRtree, iRowid, pNode->iNode);
 }
-static int isVowel(const char *z){
-  int j;
-  char x = *z;
-  if( x==0 ) return 0;
-  assert( x>='a' && x<='z' );
-  j = cType[x-'a'];
-  if( j<2 ) return 1-j;
-  return isConsonant(z + 1);
+
+static int SplitNode(
+  Rtree *pRtree,
+  RtreeNode *pNode,
+  RtreeCell *pCell,
+  int iHeight
+){
+  int i;
+  int newCellIsRight = 0;
+
+  int rc = SQLITE_OK;
+  int nCell = NCELL(pNode);
+  RtreeCell *aCell;
+  int *aiUsed;
+
+  RtreeNode *pLeft = 0;
+  RtreeNode *pRight = 0;
+
+  RtreeCell leftbbox;
+  RtreeCell rightbbox;
+
+  /* Allocate an array and populate it with a copy of pCell and 
+  ** all cells from node pLeft. Then zero the original node.
+  */
+  aCell = sqlite3_malloc((sizeof(RtreeCell)+sizeof(int))*(nCell+1));
+  if( !aCell ){
+    rc = SQLITE_NOMEM;
+    goto splitnode_out;
+  }
+  aiUsed = (int *)&aCell[nCell+1];
+  memset(aiUsed, 0, sizeof(int)*(nCell+1));
+  for(i=0; i<nCell; i++){
+    nodeGetCell(pRtree, pNode, i, &aCell[i]);
+  }
+  nodeZero(pRtree, pNode);
+  memcpy(&aCell[nCell], pCell, sizeof(RtreeCell));
+  nCell++;
+
+  if( pNode->iNode==1 ){
+    pRight = nodeNew(pRtree, pNode, 1);
+    pLeft = nodeNew(pRtree, pNode, 1);
+    pRtree->iDepth++;
+    pNode->isDirty = 1;
+    writeInt16(pNode->zData, pRtree->iDepth);
+  }else{
+    pLeft = pNode;
+    pRight = nodeNew(pRtree, pLeft->pParent, 1);
+    nodeReference(pLeft);
+  }
+
+  if( !pLeft || !pRight ){
+    rc = SQLITE_NOMEM;
+    goto splitnode_out;
+  }
+
+  memset(pLeft->zData, 0, pRtree->iNodeSize);
+  memset(pRight->zData, 0, pRtree->iNodeSize);
+
+  rc = AssignCells(pRtree, aCell, nCell, pLeft, pRight, &leftbbox, &rightbbox);
+  if( rc!=SQLITE_OK ){
+    goto splitnode_out;
+  }
+
+  /* Ensure both child nodes have node numbers assigned to them. */
+  if( (0==pRight->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)))
+   || (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft)))
+  ){
+    goto splitnode_out;
+  }
+
+  rightbbox.iRowid = pRight->iNode;
+  leftbbox.iRowid = pLeft->iNode;
+
+  if( pNode->iNode==1 ){
+    rc = rtreeInsertCell(pRtree, pLeft->pParent, &leftbbox, iHeight+1);
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
+  }else{
+    RtreeNode *pParent = pLeft->pParent;
+    int iCell = nodeParentIndex(pRtree, pLeft);
+    nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
+    AdjustTree(pRtree, pParent, &leftbbox);
+  }
+  if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){
+    goto splitnode_out;
+  }
+
+  for(i=0; i<NCELL(pRight); i++){
+    i64 iRowid = nodeGetRowid(pRtree, pRight, i);
+    rc = updateMapping(pRtree, iRowid, pRight, iHeight);
+    if( iRowid==pCell->iRowid ){
+      newCellIsRight = 1;
+    }
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
+  }
+  if( pNode->iNode==1 ){
+    for(i=0; i<NCELL(pLeft); i++){
+      i64 iRowid = nodeGetRowid(pRtree, pLeft, i);
+      rc = updateMapping(pRtree, iRowid, pLeft, iHeight);
+      if( rc!=SQLITE_OK ){
+        goto splitnode_out;
+      }
+    }
+  }else if( newCellIsRight==0 ){
+    rc = updateMapping(pRtree, pCell->iRowid, pLeft, iHeight);
+  }
+
+  if( rc==SQLITE_OK ){
+    rc = nodeRelease(pRtree, pRight);
+    pRight = 0;
+  }
+  if( rc==SQLITE_OK ){
+    rc = nodeRelease(pRtree, pLeft);
+    pLeft = 0;
+  }
+
+splitnode_out:
+  nodeRelease(pRtree, pRight);
+  nodeRelease(pRtree, pLeft);
+  sqlite3_free(aCell);
+  return rc;
 }
 
-/*
-** Let any sequence of one or more vowels be represented by V and let
-** C be sequence of one or more consonants.  Then every word can be
-** represented as:
-**
-**           [C] (VC){m} [V]
-**
-** In prose:  A word is an optional consonant followed by zero or
-** vowel-consonant pairs followed by an optional vowel.  "m" is the
-** number of vowel consonant pairs.  This routine computes the value
-** of m for the first i bytes of a word.
-**
-** Return true if the m-value for z is 1 or more.  In other words,
-** return true if z contains at least one vowel that is followed
-** by a consonant.
-**
-** In this routine z[] is in reverse order.  So we are really looking
-** for an instance of of a consonant followed by a vowel.
-*/
-static int m_gt_0(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){
+  int rc = SQLITE_OK;
+  if( pLeaf->iNode!=1 && pLeaf->pParent==0 ){
+    sqlite3_bind_int64(pRtree->pReadParent, 1, pLeaf->iNode);
+    if( sqlite3_step(pRtree->pReadParent)==SQLITE_ROW ){
+      i64 iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
+      rc = nodeAcquire(pRtree, iNode, 0, &pLeaf->pParent);
+    }else{
+      rc = SQLITE_ERROR;
+    }
+    sqlite3_reset(pRtree->pReadParent);
+    if( rc==SQLITE_OK ){
+      rc = fixLeafParent(pRtree, pLeaf->pParent);
+    }
+  }
+  return rc;
 }
 
-/* Like mgt0 above except we are looking for a value of m which is
-** exactly 1
-*/
-static int m_eq_1(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 1;
-  while( isConsonant(z) ){ z++; }
-  return *z==0;
+static int deleteCell(Rtree *, RtreeNode *, int, int);
+
+static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){
+  int rc;
+  RtreeNode *pParent;
+  int iCell;
+
+  assert( pNode->nRef==1 );
+
+  /* Remove the entry in the parent cell. */
+  iCell = nodeParentIndex(pRtree, pNode);
+  pParent = pNode->pParent;
+  pNode->pParent = 0;
+  if( SQLITE_OK!=(rc = deleteCell(pRtree, pParent, iCell, iHeight+1)) 
+   || SQLITE_OK!=(rc = nodeRelease(pRtree, pParent))
+  ){
+    return rc;
+  }
+
+  /* Remove the xxx_node entry. */
+  sqlite3_bind_int64(pRtree->pDeleteNode, 1, pNode->iNode);
+  sqlite3_step(pRtree->pDeleteNode);
+  if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteNode)) ){
+    return rc;
+  }
+
+  /* Remove the xxx_parent entry. */
+  sqlite3_bind_int64(pRtree->pDeleteParent, 1, pNode->iNode);
+  sqlite3_step(pRtree->pDeleteParent);
+  if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteParent)) ){
+    return rc;
+  }
+  
+  /* Remove the node from the in-memory hash table and link it into
+  ** the Rtree.pDeleted list. Its contents will be re-inserted later on.
+  */
+  nodeHashDelete(pRtree, pNode);
+  pNode->iNode = iHeight;
+  pNode->pNext = pRtree->pDeleted;
+  pNode->nRef++;
+  pRtree->pDeleted = pNode;
+
+  return SQLITE_OK;
 }
 
-/* Like mgt0 above except we are looking for a value of m>1 instead
-** or m>0
-*/
-static int m_gt_1(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static void fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode *pParent = pNode->pParent;
+  if( pParent ){
+    int ii; 
+    int nCell = NCELL(pNode);
+    RtreeCell box;                            /* Bounding box for pNode */
+    nodeGetCell(pRtree, pNode, 0, &box);
+    for(ii=1; ii<nCell; ii++){
+      RtreeCell cell;
+      nodeGetCell(pRtree, pNode, ii, &cell);
+      cellUnion(pRtree, &box, &cell);
+    }
+    box.iRowid = pNode->iNode;
+    ii = nodeParentIndex(pRtree, pNode);
+    nodeOverwriteCell(pRtree, pParent, &box, ii);
+    fixBoundingBox(pRtree, pParent);
+  }
 }
 
 /*
-** Return TRUE if there is a vowel anywhere within z[0..n-1]
+** Delete the cell at index iCell of node pNode. After removing the
+** cell, adjust the r-tree data structure if required.
 */
-static int hasVowel(const char *z){
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){
+  int rc;
+
+  if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){
+    return rc;
+  }
+
+  /* Remove the cell from the node. This call just moves bytes around
+  ** the in-memory node image, so it cannot fail.
+  */
+  nodeDeleteCell(pRtree, pNode, iCell);
+
+  /* If the node is not the tree root and now has less than the minimum
+  ** number of cells, remove it from the tree. Otherwise, update the
+  ** cell in the parent node so that it tightly contains the updated
+  ** node.
+  */
+  if( pNode->iNode!=1 ){
+    RtreeNode *pParent = pNode->pParent;
+    if( (pParent->iNode!=1 || NCELL(pParent)!=1) 
+     && (NCELL(pNode)<RTREE_MINCELLS(pRtree))
+    ){
+      rc = removeNode(pRtree, pNode, iHeight);
+    }else{
+      fixBoundingBox(pRtree, pNode);
+    }
+  }
+
+  return rc;
 }
 
-/*
-** Return TRUE if the word ends in a double consonant.
-**
-** The text is reversed here. So we are really looking at
-** the first two characters of z[].
-*/
-static int doubleConsonant(const char *z){
-  return isConsonant(z) && z[0]==z[1] && isConsonant(z+1);
+static int Reinsert(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  RtreeCell *pCell, 
+  int iHeight
+){
+  int *aOrder;
+  int *aSpare;
+  RtreeCell *aCell;
+  float *aDistance;
+  int nCell;
+  float aCenterCoord[RTREE_MAX_DIMENSIONS];
+  int iDim;
+  int ii;
+  int rc = SQLITE_OK;
+
+  memset(aCenterCoord, 0, sizeof(float)*RTREE_MAX_DIMENSIONS);
+
+  nCell = NCELL(pNode)+1;
+
+  /* Allocate the buffers used by this operation. The allocation is
+  ** relinquished before this function returns.
+  */
+  aCell = (RtreeCell *)sqlite3_malloc(nCell * (
+    sizeof(RtreeCell) +         /* aCell array */
+    sizeof(int)       +         /* aOrder array */
+    sizeof(int)       +         /* aSpare array */
+    sizeof(float)               /* aDistance array */
+  ));
+  if( !aCell ){
+    return SQLITE_NOMEM;
+  }
+  aOrder    = (int *)&aCell[nCell];
+  aSpare    = (int *)&aOrder[nCell];
+  aDistance = (float *)&aSpare[nCell];
+
+  for(ii=0; ii<nCell; ii++){
+    if( ii==(nCell-1) ){
+      memcpy(&aCell[ii], pCell, sizeof(RtreeCell));
+    }else{
+      nodeGetCell(pRtree, pNode, ii, &aCell[ii]);
+    }
+    aOrder[ii] = ii;
+    for(iDim=0; iDim<pRtree->nDim; iDim++){
+      aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2]);
+      aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2+1]);
+    }
+  }
+  for(iDim=0; iDim<pRtree->nDim; iDim++){
+    aCenterCoord[iDim] = aCenterCoord[iDim]/((float)nCell*2.0);
+  }
+
+  for(ii=0; ii<nCell; ii++){
+    aDistance[ii] = 0.0;
+    for(iDim=0; iDim<pRtree->nDim; iDim++){
+      float coord = DCOORD(aCell[ii].aCoord[iDim*2+1]) - 
+          DCOORD(aCell[ii].aCoord[iDim*2]);
+      aDistance[ii] += (coord-aCenterCoord[iDim])*(coord-aCenterCoord[iDim]);
+    }
+  }
+
+  SortByDistance(aOrder, nCell, aDistance, aSpare);
+  nodeZero(pRtree, pNode);
+
+  for(ii=0; rc==SQLITE_OK && ii<(nCell-(RTREE_MINCELLS(pRtree)+1)); ii++){
+    RtreeCell *p = &aCell[aOrder[ii]];
+    nodeInsertCell(pRtree, pNode, p);
+    if( p->iRowid==pCell->iRowid ){
+      if( iHeight==0 ){
+        rc = rowidWrite(pRtree, p->iRowid, pNode->iNode);
+      }else{
+        rc = parentWrite(pRtree, p->iRowid, pNode->iNode);
+      }
+    }
+  }
+  if( rc==SQLITE_OK ){
+    fixBoundingBox(pRtree, pNode);
+  }
+  for(; rc==SQLITE_OK && ii<nCell; ii++){
+    /* Find a node to store this cell in. pNode->iNode currently contains
+    ** the height of the sub-tree headed by the cell.
+    */
+    RtreeNode *pInsert;
+    RtreeCell *p = &aCell[aOrder[ii]];
+    rc = ChooseLeaf(pRtree, p, iHeight, &pInsert);
+    if( rc==SQLITE_OK ){
+      int rc2;
+      rc = rtreeInsertCell(pRtree, pInsert, p, iHeight);
+      rc2 = nodeRelease(pRtree, pInsert);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+  }
+
+  sqlite3_free(aCell);
+  return rc;
 }
 
 /*
-** Return TRUE if the word ends with three letters which
-** are consonant-vowel-consonent and where the final consonant
-** is not 'w', 'x', or 'y'.
-**
-** The word is reversed here.  So we are really checking the
-** first three letters and the first one cannot be in [wxy].
+** Insert cell pCell into node pNode. Node pNode is the head of a 
+** subtree iHeight high (leaf nodes have iHeight==0).
 */
-static int star_oh(const char *z){
-  return
-    z[0]!=0 && isConsonant(z) &&
-    z[0]!='w' && z[0]!='x' && z[0]!='y' &&
-    z[1]!=0 && isVowel(z+1) &&
-    z[2]!=0 && isConsonant(z+2);
+static int rtreeInsertCell(
+  Rtree *pRtree,
+  RtreeNode *pNode,
+  RtreeCell *pCell,
+  int iHeight
+){
+  int rc = SQLITE_OK;
+  if( iHeight>0 ){
+    RtreeNode *pChild = nodeHashLookup(pRtree, pCell->iRowid);
+    if( pChild ){
+      nodeRelease(pRtree, pChild->pParent);
+      nodeReference(pNode);
+      pChild->pParent = pNode;
+    }
+  }
+  if( nodeInsertCell(pRtree, pNode, pCell) ){
+#if VARIANT_RSTARTREE_REINSERT
+    if( iHeight<=pRtree->iReinsertHeight || pNode->iNode==1){
+      rc = SplitNode(pRtree, pNode, pCell, iHeight);
+    }else{
+      pRtree->iReinsertHeight = iHeight;
+      rc = Reinsert(pRtree, pNode, pCell, iHeight);
+    }
+#else
+    rc = SplitNode(pRtree, pNode, pCell, iHeight);
+#endif
+  }else{
+    AdjustTree(pRtree, pNode, pCell);
+    if( iHeight==0 ){
+      rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
+    }else{
+      rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+    }
+  }
+  return rc;
+}
+
+static int reinsertNodeContent(Rtree *pRtree, RtreeNode *pNode){
+  int ii;
+  int rc = SQLITE_OK;
+  int nCell = NCELL(pNode);
+
+  for(ii=0; rc==SQLITE_OK && ii<nCell; ii++){
+    RtreeNode *pInsert;
+    RtreeCell cell;
+    nodeGetCell(pRtree, pNode, ii, &cell);
+
+    /* Find a node to store this cell in. pNode->iNode currently contains
+    ** the height of the sub-tree headed by the cell.
+    */
+    rc = ChooseLeaf(pRtree, &cell, pNode->iNode, &pInsert);
+    if( rc==SQLITE_OK ){
+      int rc2;
+      rc = rtreeInsertCell(pRtree, pInsert, &cell, pNode->iNode);
+      rc2 = nodeRelease(pRtree, pInsert);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+  }
+  return rc;
 }
 
 /*
-** If the word ends with zFrom and xCond() is true for the stem
-** of the word that preceeds the zFrom ending, then change the 
-** ending to zTo.
-**
-** The input word *pz and zFrom are both in reverse order.  zTo
-** is in normal order. 
-**
-** Return TRUE if zFrom matches.  Return FALSE if zFrom does not
-** match.  Not that TRUE is returned even if xCond() fails and
-** no substitution occurs.
+** Select a currently unused rowid for a new r-tree record.
 */
-static int stem(
-  char **pz,             /* The word being stemmed (Reversed) */
-  const char *zFrom,     /* If the ending matches this... (Reversed) */
-  const char *zTo,       /* ... change the ending to this (not reversed) */
-  int (*xCond)(const char*)   /* Condition that must be true */
-){
-  char *z = *pz;
-  while( *zFrom && *zFrom==*z ){ z++; zFrom++; }
-  if( *zFrom!=0 ) return 0;
-  if( xCond && !xCond(z) ) return 1;
-  while( *zTo ){
-    *(--z) = *(zTo++);
+static int newRowid(Rtree *pRtree, i64 *piRowid){
+  int rc;
+  sqlite3_bind_null(pRtree->pWriteRowid, 1);
+  sqlite3_bind_null(pRtree->pWriteRowid, 2);
+  sqlite3_step(pRtree->pWriteRowid);
+  rc = sqlite3_reset(pRtree->pWriteRowid);
+  *piRowid = sqlite3_last_insert_rowid(pRtree->db);
+  return rc;
+}
+
+#ifndef NDEBUG
+static int hashIsEmpty(Rtree *pRtree){
+  int ii;
+  for(ii=0; ii<HASHSIZE; ii++){
+    assert( !pRtree->aHash[ii] );
   }
-  *pz = z;
   return 1;
 }
+#endif
 
 /*
-** This is the fallback stemmer used when the porter stemmer is
-** inappropriate.  The input word is copied into the output with
-** US-ASCII case folding.  If the input word is too long (more
-** than 20 bytes if it contains no digits or more than 6 bytes if
-** it contains digits) then word is truncated to 20 or 6 bytes
-** by taking 10 or 3 bytes from the beginning and end.
+** The xUpdate method for rtree module virtual tables.
 */
-static void copy_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
-  int i, mx, j;
-  int hasDigit = 0;
-  for(i=0; i<nIn; i++){
-    int c = zIn[i];
-    if( c>='A' && c<='Z' ){
-      zOut[i] = c - 'A' + 'a';
+static int rtreeUpdate(
+  sqlite3_vtab *pVtab, 
+  int nData, 
+  sqlite3_value **azData, 
+  sqlite_int64 *pRowid
+){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc = SQLITE_OK;
+
+  rtreeReference(pRtree);
+
+  assert(nData>=1);
+  assert(hashIsEmpty(pRtree));
+
+  /* If azData[0] is not an SQL NULL value, it is the rowid of a
+  ** record to delete from the r-tree table. The following block does
+  ** just that.
+  */
+  if( sqlite3_value_type(azData[0])!=SQLITE_NULL ){
+    i64 iDelete;                /* The rowid to delete */
+    RtreeNode *pLeaf;           /* Leaf node containing record iDelete */
+    int iCell;                  /* Index of iDelete cell in pLeaf */
+    RtreeNode *pRoot;
+
+    /* Obtain a reference to the root node to initialise Rtree.iDepth */
+    rc = nodeAcquire(pRtree, 1, 0, &pRoot);
+
+    /* Obtain a reference to the leaf node that contains the entry 
+    ** about to be deleted. 
+    */
+    if( rc==SQLITE_OK ){
+      iDelete = sqlite3_value_int64(azData[0]);
+      rc = findLeafNode(pRtree, iDelete, &pLeaf);
+    }
+
+    /* Delete the cell in question from the leaf node. */
+    if( rc==SQLITE_OK ){
+      int rc2;
+      iCell = nodeRowidIndex(pRtree, pLeaf, iDelete);
+      rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      rc2 = nodeRelease(pRtree, pLeaf);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+
+    /* Delete the corresponding entry in the <rtree>_rowid table. */
+    if( rc==SQLITE_OK ){
+      sqlite3_bind_int64(pRtree->pDeleteRowid, 1, iDelete);
+      sqlite3_step(pRtree->pDeleteRowid);
+      rc = sqlite3_reset(pRtree->pDeleteRowid);
+    }
+
+    /* Check if the root node now has exactly one child. If so, remove
+    ** it, schedule the contents of the child for reinsertion and 
+    ** reduce the tree height by one.
+    **
+    ** This is equivalent to copying the contents of the child into
+    ** the root node (the operation that Gutman's paper says to perform 
+    ** in this scenario).
+    */
+    if( rc==SQLITE_OK && pRtree->iDepth>0 ){
+      if( rc==SQLITE_OK && NCELL(pRoot)==1 ){
+        RtreeNode *pChild;
+        i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
+        rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
+        if( rc==SQLITE_OK ){
+          rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
+        }
+        if( rc==SQLITE_OK ){
+          pRtree->iDepth--;
+          writeInt16(pRoot->zData, pRtree->iDepth);
+          pRoot->isDirty = 1;
+        }
+      }
+    }
+
+    /* Re-insert the contents of any underfull nodes removed from the tree. */
+    for(pLeaf=pRtree->pDeleted; pLeaf; pLeaf=pRtree->pDeleted){
+      if( rc==SQLITE_OK ){
+        rc = reinsertNodeContent(pRtree, pLeaf);
+      }
+      pRtree->pDeleted = pLeaf->pNext;
+      sqlite3_free(pLeaf);
+    }
+
+    /* Release the reference to the root node. */
+    if( rc==SQLITE_OK ){
+      rc = nodeRelease(pRtree, pRoot);
+    }else{
+      nodeRelease(pRtree, pRoot);
+    }
+  }
+
+  /* If the azData[] array contains more than one element, elements
+  ** (azData[2]..azData[argc-1]) contain a new record to insert into
+  ** the r-tree structure.
+  */
+  if( rc==SQLITE_OK && nData>1 ){
+    /* Insert a new record into the r-tree */
+    RtreeCell cell;
+    int ii;
+    RtreeNode *pLeaf;
+
+    /* Populate the cell.aCoord[] array. The first coordinate is azData[3]. */
+    assert( nData==(pRtree->nDim*2 + 3) );
+    if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+      for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+        cell.aCoord[ii].f = (float)sqlite3_value_double(azData[ii+3]);
+        cell.aCoord[ii+1].f = (float)sqlite3_value_double(azData[ii+4]);
+        if( cell.aCoord[ii].f>cell.aCoord[ii+1].f ){
+          rc = SQLITE_CONSTRAINT;
+          goto constraint;
+        }
+      }
     }else{
-      if( c>='0' && c<='9' ) hasDigit = 1;
-      zOut[i] = c;
+      for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+        cell.aCoord[ii].i = sqlite3_value_int(azData[ii+3]);
+        cell.aCoord[ii+1].i = sqlite3_value_int(azData[ii+4]);
+        if( cell.aCoord[ii].i>cell.aCoord[ii+1].i ){
+          rc = SQLITE_CONSTRAINT;
+          goto constraint;
+        }
+      }
     }
-  }
-  mx = hasDigit ? 3 : 10;
-  if( nIn>mx*2 ){
-    for(j=mx, i=nIn-mx; i<nIn; i++, j++){
-      zOut[j] = zOut[i];
+
+    /* Figure out the rowid of the new row. */
+    if( sqlite3_value_type(azData[2])==SQLITE_NULL ){
+      rc = newRowid(pRtree, &cell.iRowid);
+    }else{
+      cell.iRowid = sqlite3_value_int64(azData[2]);
+      sqlite3_bind_int64(pRtree->pReadRowid, 1, cell.iRowid);
+      if( SQLITE_ROW==sqlite3_step(pRtree->pReadRowid) ){
+        sqlite3_reset(pRtree->pReadRowid);
+        rc = SQLITE_CONSTRAINT;
+        goto constraint;
+      }
+      rc = sqlite3_reset(pRtree->pReadRowid);
+    }
+
+    if( rc==SQLITE_OK ){
+      rc = ChooseLeaf(pRtree, &cell, 0, &pLeaf);
+    }
+    if( rc==SQLITE_OK ){
+      int rc2;
+      pRtree->iReinsertHeight = -1;
+      rc = rtreeInsertCell(pRtree, pLeaf, &cell, 0);
+      rc2 = nodeRelease(pRtree, pLeaf);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
     }
-    i = j;
   }
-  zOut[i] = 0;
-  *pnOut = i;
-}
 
+constraint:
+  rtreeRelease(pRtree);
+  return rc;
+}
 
 /*
-** Stem the input word zIn[0..nIn-1].  Store the output in zOut.
-** zOut is at least big enough to hold nIn bytes.  Write the actual
-** size of the output word (exclusive of the '\0' terminator) into *pnOut.
-**
-** Any upper-case characters in the US-ASCII character set ([A-Z])
-** are converted to lower case.  Upper-case UTF characters are
-** unchanged.
-**
-** Words that are longer than about 20 bytes are stemmed by retaining
-** a few bytes from the beginning and the end of the word.  If the
-** word contains digits, 3 bytes are taken from the beginning and
-** 3 bytes from the end.  For long words without digits, 10 bytes
-** are taken from each end.  US-ASCII case folding still applies.
-** 
-** If the input word contains not digits but does characters not 
-** in [a-zA-Z] then no stemming is attempted and this routine just 
-** copies the input into the input into the output with US-ASCII
-** case folding.
-**
-** Stemming never increases the length of the word.  So there is
-** no chance of overflowing the zOut buffer.
+** The xRename method for rtree module virtual tables.
 */
-static void porter_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
-  int i, j, c;
-  char zReverse[28];
-  char *z, *z2;
-  if( nIn<3 || nIn>=sizeof(zReverse)-7 ){
-    /* The word is too big or too small for the porter stemmer.
-    ** Fallback to the copy stemmer */
-    copy_stemmer(zIn, nIn, zOut, pnOut);
-    return;
+static int rtreeRename(sqlite3_vtab *pVtab, const char *zNewName){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc = SQLITE_NOMEM;
+  char *zSql = sqlite3_mprintf(
+    "ALTER TABLE %Q.'%q_node'   RENAME TO \"%w_node\";"
+    "ALTER TABLE %Q.'%q_parent' RENAME TO \"%w_parent\";"
+    "ALTER TABLE %Q.'%q_rowid'  RENAME TO \"%w_rowid\";"
+    , pRtree->zDb, pRtree->zName, zNewName 
+    , pRtree->zDb, pRtree->zName, zNewName 
+    , pRtree->zDb, pRtree->zName, zNewName
+  );
+  if( zSql ){
+    rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
   }
-  for(i=0, j=sizeof(zReverse)-6; i<nIn; i++, j--){
-    c = zIn[i];
-    if( c>='A' && c<='Z' ){
-      zReverse[j] = c + 'a' - 'A';
-    }else if( c>='a' && c<='z' ){
-      zReverse[j] = c;
-    }else{
-      /* The use of a character not in [a-zA-Z] means that we fallback
-      ** to the copy stemmer */
-      copy_stemmer(zIn, nIn, zOut, pnOut);
-      return;
+  return rc;
+}
+
+static sqlite3_module rtreeModule = {
+  0,                         /* iVersion */
+  rtreeCreate,                /* xCreate - create a table */
+  rtreeConnect,               /* xConnect - connect to an existing table */
+  rtreeBestIndex,             /* xBestIndex - Determine search strategy */
+  rtreeDisconnect,            /* xDisconnect - Disconnect from a table */
+  rtreeDestroy,               /* xDestroy - Drop a table */
+  rtreeOpen,                  /* xOpen - open a cursor */
+  rtreeClose,                 /* xClose - close a cursor */
+  rtreeFilter,                /* xFilter - configure scan constraints */
+  rtreeNext,                  /* xNext - advance a cursor */
+  rtreeEof,                   /* xEof */
+  rtreeColumn,                /* xColumn - read data */
+  rtreeRowid,                 /* xRowid - read data */
+  rtreeUpdate,                /* xUpdate - write data */
+  0,                          /* xBegin - begin transaction */
+  0,                          /* xSync - sync transaction */
+  0,                          /* xCommit - commit transaction */
+  0,                          /* xRollback - rollback transaction */
+  0,                          /* xFindFunction - function overloading */
+  rtreeRename                 /* xRename - rename the table */
+};
+
+static int rtreeSqlInit(
+  Rtree *pRtree, 
+  sqlite3 *db, 
+  const char *zDb, 
+  const char *zPrefix, 
+  int isCreate
+){
+  int rc = SQLITE_OK;
+
+  #define N_STATEMENT 9
+  static const char *azSql[N_STATEMENT] = {
+    /* Read and write the xxx_node table */
+    "SELECT data FROM '%q'.'%q_node' WHERE nodeno = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_node' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_node' WHERE nodeno = :1",
+
+    /* Read and write the xxx_rowid table */
+    "SELECT nodeno FROM '%q'.'%q_rowid' WHERE rowid = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_rowid' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_rowid' WHERE rowid = :1",
+
+    /* Read and write the xxx_parent table */
+    "SELECT parentnode FROM '%q'.'%q_parent' WHERE nodeno = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_parent' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_parent' WHERE nodeno = :1"
+  };
+  sqlite3_stmt **appStmt[N_STATEMENT];
+  int i;
+
+  pRtree->db = db;
+
+  if( isCreate ){
+    char *zCreate = sqlite3_mprintf(
+"CREATE TABLE \"%w\".\"%w_node\"(nodeno INTEGER PRIMARY KEY, data BLOB);"
+"CREATE TABLE \"%w\".\"%w_rowid\"(rowid INTEGER PRIMARY KEY, nodeno INTEGER);"
+"CREATE TABLE \"%w\".\"%w_parent\"(nodeno INTEGER PRIMARY KEY, parentnode INTEGER);"
+"INSERT INTO '%q'.'%q_node' VALUES(1, zeroblob(%d))",
+      zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, pRtree->iNodeSize
+    );
+    if( !zCreate ){
+      return SQLITE_NOMEM;
+    }
+    rc = sqlite3_exec(db, zCreate, 0, 0, 0);
+    sqlite3_free(zCreate);
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
   }
-  memset(&zReverse[sizeof(zReverse)-5], 0, 5);
-  z = &zReverse[j+1];
 
+  appStmt[0] = &pRtree->pReadNode;
+  appStmt[1] = &pRtree->pWriteNode;
+  appStmt[2] = &pRtree->pDeleteNode;
+  appStmt[3] = &pRtree->pReadRowid;
+  appStmt[4] = &pRtree->pWriteRowid;
+  appStmt[5] = &pRtree->pDeleteRowid;
+  appStmt[6] = &pRtree->pReadParent;
+  appStmt[7] = &pRtree->pWriteParent;
+  appStmt[8] = &pRtree->pDeleteParent;
 
-  /* Step 1a */
-  if( z[0]=='s' ){
-    if(
-     !stem(&z, "sess", "ss", 0) &&
-     !stem(&z, "sei", "i", 0)  &&
-     !stem(&z, "ss", "ss", 0)
-    ){
-      z++;
+  for(i=0; i<N_STATEMENT && rc==SQLITE_OK; i++){
+    char *zSql = sqlite3_mprintf(azSql[i], zDb, zPrefix);
+    if( zSql ){
+      rc = sqlite3_prepare_v2(db, zSql, -1, appStmt[i], 0); 
+    }else{
+      rc = SQLITE_NOMEM;
     }
+    sqlite3_free(zSql);
   }
 
-  /* Step 1b */  
-  z2 = z;
-  if( stem(&z, "dee", "ee", m_gt_0) ){
-    /* Do nothing.  The work was all in the test */
-  }else if( 
-     (stem(&z, "gni", "", hasVowel) || stem(&z, "de", "", hasVowel))
-      && z!=z2
-  ){
-     if( stem(&z, "ta", "ate", 0) ||
-         stem(&z, "lb", "ble", 0) ||
-         stem(&z, "zi", "ize", 0) ){
-       /* Do nothing.  The work was all in the test */
-     }else if( doubleConsonant(z) && (*z!='l' && *z!='s' && *z!='z') ){
-       z++;
-     }else if( m_eq_1(z) && star_oh(z) ){
-       *(--z) = 'e';
-     }
-  }
+  return rc;
+}
 
-  /* Step 1c */
-  if( z[0]=='y' && hasVowel(z+1) ){
-    z[0] = 'i';
+/*
+** This routine queries database handle db for the page-size used by
+** database zDb. If successful, the page-size in bytes is written to
+** *piPageSize and SQLITE_OK returned. Otherwise, and an SQLite error 
+** code is returned.
+*/
+static int getPageSize(sqlite3 *db, const char *zDb, int *piPageSize){
+  int rc = SQLITE_NOMEM;
+  char *zSql;
+  sqlite3_stmt *pStmt = 0;
+
+  zSql = sqlite3_mprintf("PRAGMA %Q.page_size", zDb);
+  if( !zSql ){
+    return SQLITE_NOMEM;
   }
 
-  /* Step 2 */
-  switch( z[1] ){
-   case 'a':
-     stem(&z, "lanoita", "ate", m_gt_0) ||
-     stem(&z, "lanoit", "tion", m_gt_0);
-     break;
-   case 'c':
-     stem(&z, "icne", "ence", m_gt_0) ||
-     stem(&z, "icna", "ance", m_gt_0);
-     break;
-   case 'e':
-     stem(&z, "rezi", "ize", m_gt_0);
-     break;
-   case 'g':
-     stem(&z, "igol", "log", m_gt_0);
-     break;
-   case 'l':
-     stem(&z, "ilb", "ble", m_gt_0) ||
-     stem(&z, "illa", "al", m_gt_0) ||
-     stem(&z, "iltne", "ent", m_gt_0) ||
-     stem(&z, "ile", "e", m_gt_0) ||
-     stem(&z, "ilsuo", "ous", m_gt_0);
-     break;
-   case 'o':
-     stem(&z, "noitazi", "ize", m_gt_0) ||
-     stem(&z, "noita", "ate", m_gt_0) ||
-     stem(&z, "rota", "ate", m_gt_0);
-     break;
-   case 's':
-     stem(&z, "msila", "al", m_gt_0) ||
-     stem(&z, "ssenevi", "ive", m_gt_0) ||
-     stem(&z, "ssenluf", "ful", m_gt_0) ||
-     stem(&z, "ssensuo", "ous", m_gt_0);
-     break;
-   case 't':
-     stem(&z, "itila", "al", m_gt_0) ||
-     stem(&z, "itivi", "ive", m_gt_0) ||
-     stem(&z, "itilib", "ble", m_gt_0);
-     break;
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  sqlite3_free(zSql);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
 
-  /* Step 3 */
-  switch( z[0] ){
-   case 'e':
-     stem(&z, "etaci", "ic", m_gt_0) ||
-     stem(&z, "evita", "", m_gt_0)   ||
-     stem(&z, "ezila", "al", m_gt_0);
-     break;
-   case 'i':
-     stem(&z, "itici", "ic", m_gt_0);
-     break;
-   case 'l':
-     stem(&z, "laci", "ic", m_gt_0) ||
-     stem(&z, "luf", "", m_gt_0);
-     break;
-   case 's':
-     stem(&z, "ssen", "", m_gt_0);
-     break;
+  if( SQLITE_ROW==sqlite3_step(pStmt) ){
+    *piPageSize = sqlite3_column_int(pStmt, 0);
   }
+  return sqlite3_finalize(pStmt);
+}
 
-  /* Step 4 */
-  switch( z[1] ){
-   case 'a':
-     if( z[0]=='l' && m_gt_1(z+2) ){
-       z += 2;
-     }
-     break;
-   case 'c':
-     if( z[0]=='e' && z[2]=='n' && (z[3]=='a' || z[3]=='e')  && m_gt_1(z+4)  ){
-       z += 4;
-     }
-     break;
-   case 'e':
-     if( z[0]=='r' && m_gt_1(z+2) ){
-       z += 2;
-     }
-     break;
-   case 'i':
-     if( z[0]=='c' && m_gt_1(z+2) ){
-       z += 2;
-     }
-     break;
-   case 'l':
-     if( z[0]=='e' && z[2]=='b' && (z[3]=='a' || z[3]=='i') && m_gt_1(z+4) ){
-       z += 4;
-     }
-     break;
-   case 'n':
-     if( z[0]=='t' ){
-       if( z[2]=='a' ){
-         if( m_gt_1(z+3) ){
-           z += 3;
-         }
-       }else if( z[2]=='e' ){
-         stem(&z, "tneme", "", m_gt_1) ||
-         stem(&z, "tnem", "", m_gt_1) ||
-         stem(&z, "tne", "", m_gt_1);
-       }
-     }
-     break;
-   case 'o':
-     if( z[0]=='u' ){
-       if( m_gt_1(z+2) ){
-         z += 2;
-       }
-     }else if( z[3]=='s' || z[3]=='t' ){
-       stem(&z, "noi", "", m_gt_1);
-     }
-     break;
-   case 's':
-     if( z[0]=='m' && z[2]=='i' && m_gt_1(z+3) ){
-       z += 3;
-     }
-     break;
-   case 't':
-     stem(&z, "eta", "", m_gt_1) ||
-     stem(&z, "iti", "", m_gt_1);
-     break;
-   case 'u':
-     if( z[0]=='s' && z[2]=='o' && m_gt_1(z+3) ){
-       z += 3;
-     }
-     break;
-   case 'v':
-   case 'z':
-     if( z[0]=='e' && z[2]=='i' && m_gt_1(z+3) ){
-       z += 3;
-     }
-     break;
+/* 
+** This function is the implementation of both the xConnect and xCreate
+** methods of the r-tree virtual table.
+**
+**   argv[0]   -> module name
+**   argv[1]   -> database name
+**   argv[2]   -> table name
+**   argv[...] -> column names...
+*/
+static int rtreeInit(
+  sqlite3 *db,                        /* Database connection */
+  void *pAux,                         /* One of the RTREE_COORD_* constants */
+  int argc, const char *const*argv,   /* Parameters to CREATE TABLE statement */
+  sqlite3_vtab **ppVtab,              /* OUT: New virtual table */
+  char **pzErr,                       /* OUT: Error message, if any */
+  int isCreate                        /* True for xCreate, false for xConnect */
+){
+  int rc = SQLITE_OK;
+  int iPageSize = 0;
+  Rtree *pRtree;
+  int nDb;              /* Length of string argv[1] */
+  int nName;            /* Length of string argv[2] */
+  int eCoordType = (int)pAux;
+
+  const char *aErrMsg[] = {
+    0,                                                    /* 0 */
+    "Wrong number of columns for an rtree table",         /* 1 */
+    "Too few columns for an rtree table",                 /* 2 */
+    "Too many columns for an rtree table"                 /* 3 */
+  };
+
+  int iErr = (argc<6) ? 2 : argc>(RTREE_MAX_DIMENSIONS*2+4) ? 3 : argc%2;
+  if( aErrMsg[iErr] ){
+    *pzErr = sqlite3_mprintf("%s", aErrMsg[iErr]);
+    return SQLITE_ERROR;
   }
 
-  /* Step 5a */
-  if( z[0]=='e' ){
-    if( m_gt_1(z+1) ){
-      z++;
-    }else if( m_eq_1(z+1) && !star_oh(z+1) ){
-      z++;
-    }
+  rc = getPageSize(db, argv[1], &iPageSize);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
 
-  /* Step 5b */
-  if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
-    z++;
+  /* Allocate the sqlite3_vtab structure */
+  nDb = strlen(argv[1]);
+  nName = strlen(argv[2]);
+  pRtree = (Rtree *)sqlite3_malloc(sizeof(Rtree)+nDb+nName+2);
+  if( !pRtree ){
+    return SQLITE_NOMEM;
+  }
+  memset(pRtree, 0, sizeof(Rtree)+nDb+nName+2);
+  pRtree->nBusy = 1;
+  pRtree->base.pModule = &rtreeModule;
+  pRtree->zDb = (char *)&pRtree[1];
+  pRtree->zName = &pRtree->zDb[nDb+1];
+  pRtree->nDim = (argc-4)/2;
+  pRtree->nBytesPerCell = 8 + pRtree->nDim*4*2;
+  pRtree->eCoordType = eCoordType;
+  memcpy(pRtree->zDb, argv[1], nDb);
+  memcpy(pRtree->zName, argv[2], nName);
+
+  /* Figure out the node size to use. By default, use 64 bytes less than
+  ** the database page-size. This ensures that each node is stored on
+  ** a single database page.
+  **
+  ** If the databasd page-size is so large that more than RTREE_MAXCELLS
+  ** entries would fit in a single node, use a smaller node-size.
+  */
+  pRtree->iNodeSize = iPageSize-64;
+  if( (4+pRtree->nBytesPerCell*RTREE_MAXCELLS)<pRtree->iNodeSize ){
+    pRtree->iNodeSize = 4+pRtree->nBytesPerCell*RTREE_MAXCELLS;
   }
 
-  /* z[] is now the stemmed word in reverse order.  Flip it back
-  ** around into forward order and return.
+  /* Create/Connect to the underlying relational database schema. If
+  ** that is successful, call sqlite3_declare_vtab() to configure
+  ** the r-tree table schema.
   */
-  *pnOut = i = strlen(z);
-  zOut[i] = 0;
-  while( *z ){
-    zOut[--i] = *(z++);
+  if( (rc = rtreeSqlInit(pRtree, db, argv[1], argv[2], isCreate)) ){
+    *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
+  }else{
+    char *zSql = sqlite3_mprintf("CREATE TABLE x(%s", argv[3]);
+    char *zTmp;
+    int ii;
+    for(ii=4; zSql && ii<argc; ii++){
+      zTmp = zSql;
+      zSql = sqlite3_mprintf("%s, %s", zTmp, argv[ii]);
+      sqlite3_free(zTmp);
+    }
+    if( zSql ){
+      zTmp = zSql;
+      zSql = sqlite3_mprintf("%s);", zTmp);
+      sqlite3_free(zTmp);
+    }
+    if( !zSql ){
+      rc = SQLITE_NOMEM;
+    }else if( SQLITE_OK!=(rc = sqlite3_declare_vtab(db, zSql)) ){
+      *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
+    }
+    sqlite3_free(zSql);
+  }
+
+  if( rc==SQLITE_OK ){
+    *ppVtab = (sqlite3_vtab *)pRtree;
+  }else{
+    rtreeRelease(pRtree);
   }
+  return rc;
 }
 
-/*
-** Characters that can be part of a token.  We assume any character
-** whose value is greater than 0x80 (any UTF character) can be
-** part of a token.  In other words, delimiters all must have
-** values of 0x7f or lower.
-*/
-static const char porterIdChar[] = {
-/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
-    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
-};
-#define isDelim(C) (((ch=C)&0x80)==0 && (ch<0x30 || !porterIdChar[ch-0x30]))
 
 /*
-** Extract the next token from a tokenization cursor.  The cursor must
-** have been opened by a prior call to porterOpen().
+** Implementation of a scalar function that decodes r-tree nodes to
+** human readable strings. This can be used for debugging and analysis.
+**
+** The scalar function takes two arguments, a blob of data containing
+** an r-tree node, and the number of dimensions the r-tree indexes.
+** For a two-dimensional r-tree structure called "rt", to deserialize
+** all nodes, a statement like:
+**
+**   SELECT rtreenode(2, data) FROM rt_node;
+**
+** The human readable string takes the form of a Tcl list with one
+** entry for each cell in the r-tree node. Each entry is itself a
+** list, containing the 8-byte rowid/pageno followed by the 
+** <num-dimension>*2 coordinates.
 */
-static int porterNext(
-  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by porterOpen */
-  const char **pzToken,               /* OUT: *pzToken is the token text */
-  int *pnBytes,                       /* OUT: Number of bytes in token */
-  int *piStartOffset,                 /* OUT: Starting offset of token */
-  int *piEndOffset,                   /* OUT: Ending offset of token */
-  int *piPosition                     /* OUT: Position integer of token */
-){
-  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
-  const char *z = c->zInput;
-
-  while( c->iOffset<c->nInput ){
-    int iStartOffset, ch;
-
-    /* Scan past delimiter characters */
-    while( c->iOffset<c->nInput && isDelim(z[c->iOffset]) ){
-      c->iOffset++;
-    }
+static void rtreenode(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
+  char *zText = 0;
+  RtreeNode node;
+  Rtree tree;
+  int ii;
 
-    /* Count non-delimiter characters. */
-    iStartOffset = c->iOffset;
-    while( c->iOffset<c->nInput && !isDelim(z[c->iOffset]) ){
-      c->iOffset++;
+  memset(&node, 0, sizeof(RtreeNode));
+  memset(&tree, 0, sizeof(Rtree));
+  tree.nDim = sqlite3_value_int(apArg[0]);
+  tree.nBytesPerCell = 8 + 8 * tree.nDim;
+  node.zData = (u8 *)sqlite3_value_blob(apArg[1]);
+
+  for(ii=0; ii<NCELL(&node); ii++){
+    char zCell[512];
+    int nCell = 0;
+    RtreeCell cell;
+    int jj;
+
+    nodeGetCell(&tree, &node, ii, &cell);
+    sqlite3_snprintf(512-nCell,&zCell[nCell],"%d", cell.iRowid);
+    nCell = strlen(zCell);
+    for(jj=0; jj<tree.nDim*2; jj++){
+      sqlite3_snprintf(512-nCell,&zCell[nCell]," %f",(double)cell.aCoord[jj].f);
+      nCell = strlen(zCell);
+    }
+
+    if( zText ){
+      char *zTextNew = sqlite3_mprintf("%s {%s}", zText, zCell);
+      sqlite3_free(zText);
+      zText = zTextNew;
+    }else{
+      zText = sqlite3_mprintf("{%s}", zCell);
     }
+  }
+  
+  sqlite3_result_text(ctx, zText, -1, sqlite3_free);
+}
 
-    if( c->iOffset>iStartOffset ){
-      int n = c->iOffset-iStartOffset;
-      if( n>c->nAllocated ){
-        c->nAllocated = n+20;
-        c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
-        if( c->zToken==NULL ) return SQLITE_NOMEM;
-      }
-      porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
-      *pzToken = c->zToken;
-      *piStartOffset = iStartOffset;
-      *piEndOffset = c->iOffset;
-      *piPosition = c->iToken++;
-      return SQLITE_OK;
-    }
+static void rtreedepth(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
+  if( sqlite3_value_type(apArg[0])!=SQLITE_BLOB 
+   || sqlite3_value_bytes(apArg[0])<2
+  ){
+    sqlite3_result_error(ctx, "Invalid argument to rtreedepth()", -1); 
+  }else{
+    u8 *zBlob = (u8 *)sqlite3_value_blob(apArg[0]);
+    sqlite3_result_int(ctx, readInt16(zBlob));
   }
-  return SQLITE_DONE;
 }
 
 /*
-** The set of routines that implement the porter-stemmer tokenizer
+** Register the r-tree module with database handle db. This creates the
+** virtual table module "rtree" and the debugging/analysis scalar 
+** function "rtreenode".
 */
-static const sqlite3_tokenizer_module porterTokenizerModule = {
-  0,
-  porterCreate,
-  porterDestroy,
-  porterOpen,
-  porterClose,
-  porterNext,
-};
+SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db){
+  int rc = SQLITE_OK;
 
-/*
-** Allocate a new porter tokenizer.  Return a pointer to the new
-** tokenizer in *ppModule
-*/
-SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
-  sqlite3_tokenizer_module const**ppModule
+  if( rc==SQLITE_OK ){
+    int utf8 = SQLITE_UTF8;
+    rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
+  }
+  if( rc==SQLITE_OK ){
+    int utf8 = SQLITE_UTF8;
+    rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0);
+  }
+  if( rc==SQLITE_OK ){
+    void *c = (void *)RTREE_COORD_REAL32;
+    rc = sqlite3_create_module_v2(db, "rtree", &rtreeModule, c, 0);
+  }
+  if( rc==SQLITE_OK ){
+    void *c = (void *)RTREE_COORD_INT32;
+    rc = sqlite3_create_module_v2(db, "rtree_i32", &rtreeModule, c, 0);
+  }
+
+  return rc;
+}
+
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db,
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
 ){
-  *ppModule = &porterTokenizerModule;
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3RtreeInit(db);
 }
+#endif
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+#endif
 
-/************** End of fts3_porter.c *****************************************/
-/************** Begin file fts3_tokenizer.c **********************************/
+/************** End of rtree.c ***********************************************/
+/************** Begin file icu.c *********************************************/
 /*
-** 2007 June 22
+** 2007 May 6
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -86450,366 +109861,497 @@ SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-******************************************************************************
+*************************************************************************
+** $Id: icu.c,v 1.7 2007/12/13 21:54:11 drh Exp $
 **
-** This is part of an SQLite module implementing full-text search.
-** This particular file implements the generic tokenizer interface.
+** This file implements an integration between the ICU library 
+** ("International Components for Unicode", an open-source library 
+** for handling unicode data) and SQLite. The integration uses 
+** ICU to provide the following to SQLite:
+**
+**   * An implementation of the SQL regexp() function (and hence REGEXP
+**     operator) using the ICU uregex_XX() APIs.
+**
+**   * Implementations of the SQL scalar upper() and lower() functions
+**     for case mapping.
+**
+**   * Integration of ICU and SQLite collation seqences.
+**
+**   * An implementation of the LIKE operator that uses ICU to 
+**     provide case-independent matching.
+*/
+
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_ICU)
+
+/* Include ICU headers */
+#include <unicode/utypes.h>
+#include <unicode/uregex.h>
+#include <unicode/ustring.h>
+#include <unicode/ucol.h>
+
+
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#else
+#endif
+
+/*
+** Maximum length (in bytes) of the pattern in a LIKE or GLOB
+** operator.
+*/
+#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
+# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
+#endif
+
+/*
+** Version of sqlite3_free() that is always a function, never a macro.
+*/
+static void xFree(void *p){
+  sqlite3_free(p);
+}
+
+/*
+** Compare two UTF-8 strings for equality where the first string is
+** a "LIKE" expression. Return true (1) if they are the same and 
+** false (0) if they are different.
+*/
+static int icuLikeCompare(
+  const uint8_t *zPattern,   /* LIKE pattern */
+  const uint8_t *zString,    /* The UTF-8 string to compare against */
+  const UChar32 uEsc         /* The escape character */
+){
+  static const int MATCH_ONE = (UChar32)'_';
+  static const int MATCH_ALL = (UChar32)'%';
+
+  int iPattern = 0;       /* Current byte index in zPattern */
+  int iString = 0;        /* Current byte index in zString */
+
+  int prevEscape = 0;     /* True if the previous character was uEsc */
+
+  while( zPattern[iPattern]!=0 ){
+
+    /* Read (and consume) the next character from the input pattern. */
+    UChar32 uPattern;
+    U8_NEXT_UNSAFE(zPattern, iPattern, uPattern);
+    assert(uPattern!=0);
+
+    /* There are now 4 possibilities:
+    **
+    **     1. uPattern is an unescaped match-all character "%",
+    **     2. uPattern is an unescaped match-one character "_",
+    **     3. uPattern is an unescaped escape character, or
+    **     4. uPattern is to be handled as an ordinary character
+    */
+    if( !prevEscape && uPattern==MATCH_ALL ){
+      /* Case 1. */
+      uint8_t c;
+
+      /* Skip any MATCH_ALL or MATCH_ONE characters that follow a
+      ** MATCH_ALL. For each MATCH_ONE, skip one character in the 
+      ** test string.
+      */
+      while( (c=zPattern[iPattern]) == MATCH_ALL || c == MATCH_ONE ){
+        if( c==MATCH_ONE ){
+          if( zString[iString]==0 ) return 0;
+          U8_FWD_1_UNSAFE(zString, iString);
+        }
+        iPattern++;
+      }
+
+      if( zPattern[iPattern]==0 ) return 1;
+
+      while( zString[iString] ){
+        if( icuLikeCompare(&zPattern[iPattern], &zString[iString], uEsc) ){
+          return 1;
+        }
+        U8_FWD_1_UNSAFE(zString, iString);
+      }
+      return 0;
+
+    }else if( !prevEscape && uPattern==MATCH_ONE ){
+      /* Case 2. */
+      if( zString[iString]==0 ) return 0;
+      U8_FWD_1_UNSAFE(zString, iString);
+
+    }else if( !prevEscape && uPattern==uEsc){
+      /* Case 3. */
+      prevEscape = 1;
+
+    }else{
+      /* Case 4. */
+      UChar32 uString;
+      U8_NEXT_UNSAFE(zString, iString, uString);
+      uString = u_foldCase(uString, U_FOLD_CASE_DEFAULT);
+      uPattern = u_foldCase(uPattern, U_FOLD_CASE_DEFAULT);
+      if( uString!=uPattern ){
+        return 0;
+      }
+      prevEscape = 0;
+    }
+  }
+
+  return zString[iString]==0;
+}
+
+/*
+** Implementation of the like() SQL function.  This function implements
+** the build-in LIKE operator.  The first argument to the function is the
+** pattern and the second argument is the string.  So, the SQL statements:
+**
+**       A LIKE B
+**
+** is implemented as like(B, A). If there is an escape character E, 
+**
+**       A LIKE B ESCAPE E
+**
+** is mapped to like(B, A, E).
 */
+static void icuLikeFunc(
+  sqlite3_context *context, 
+  int argc, 
+  sqlite3_value **argv
+){
+  const unsigned char *zA = sqlite3_value_text(argv[0]);
+  const unsigned char *zB = sqlite3_value_text(argv[1]);
+  UChar32 uEsc = 0;
+
+  /* Limit the length of the LIKE or GLOB pattern to avoid problems
+  ** of deep recursion and N*N behavior in patternCompare().
+  */
+  if( sqlite3_value_bytes(argv[0])>SQLITE_MAX_LIKE_PATTERN_LENGTH ){
+    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
+    return;
+  }
+
+
+  if( argc==3 ){
+    /* The escape character string must consist of a single UTF-8 character.
+    ** Otherwise, return an error.
+    */
+    int nE= sqlite3_value_bytes(argv[2]);
+    const unsigned char *zE = sqlite3_value_text(argv[2]);
+    int i = 0;
+    if( zE==0 ) return;
+    U8_NEXT(zE, i, nE, uEsc);
+    if( i!=nE){
+      sqlite3_result_error(context, 
+          "ESCAPE expression must be a single character", -1);
+      return;
+    }
+  }
+
+  if( zA && zB ){
+    sqlite3_result_int(context, icuLikeCompare(zA, zB, uEsc));
+  }
+}
 
 /*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
+** This function is called when an ICU function called from within
+** the implementation of an SQL scalar function returns an error.
 **
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+** The scalar function context passed as the first argument is 
+** loaded with an error message based on the following two args.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
-
-#ifndef SQLITE_CORE
-  SQLITE_EXTENSION_INIT1
-#endif
+static void icuFunctionError(
+  sqlite3_context *pCtx,       /* SQLite scalar function context */
+  const char *zName,           /* Name of ICU function that failed */
+  UErrorCode e                 /* Error code returned by ICU function */
+){
+  char zBuf[128];
+  sqlite3_snprintf(128, zBuf, "ICU error: %s(): %s", zName, u_errorName(e));
+  zBuf[127] = '\0';
+  sqlite3_result_error(pCtx, zBuf, -1);
+}
 
+/*
+** Function to delete compiled regexp objects. Registered as
+** a destructor function with sqlite3_set_auxdata().
+*/
+static void icuRegexpDelete(void *p){
+  URegularExpression *pExpr = (URegularExpression *)p;
+  uregex_close(pExpr);
+}
 
 /*
-** Implementation of the SQL scalar function for accessing the underlying 
-** hash table. This function may be called as follows:
+** Implementation of SQLite REGEXP operator. This scalar function takes
+** two arguments. The first is a regular expression pattern to compile
+** the second is a string to match against that pattern. If either 
+** argument is an SQL NULL, then NULL Is returned. Otherwise, the result
+** is 1 if the string matches the pattern, or 0 otherwise.
 **
-**   SELECT <function-name>(<key-name>);
-**   SELECT <function-name>(<key-name>, <pointer>);
+** SQLite maps the regexp() function to the regexp() operator such
+** that the following two are equivalent:
 **
-** where <function-name> is the name passed as the second argument
-** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer').
+**     zString REGEXP zPattern
+**     regexp(zPattern, zString)
 **
-** If the <pointer> argument is specified, it must be a blob value
-** containing a pointer to be stored as the hash data corresponding
-** to the string <key-name>. If <pointer> is not specified, then
-** the string <key-name> must already exist in the has table. Otherwise,
-** an error is returned.
+** Uses the following ICU regexp APIs:
 **
-** Whether or not the <pointer> argument is specified, the value returned
-** is a blob containing the pointer stored as the hash data corresponding
-** to string <key-name> (after the hash-table is updated, if applicable).
+**     uregex_open()
+**     uregex_matches()
+**     uregex_close()
 */
-static void scalarFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  fts3Hash *pHash;
-  void *pPtr = 0;
-  const unsigned char *zName;
-  int nName;
+static void icuRegexpFunc(sqlite3_context *p, int nArg, sqlite3_value **apArg){
+  UErrorCode status = U_ZERO_ERROR;
+  URegularExpression *pExpr;
+  UBool res;
+  const UChar *zString = sqlite3_value_text16(apArg[1]);
 
-  assert( argc==1 || argc==2 );
-
-  pHash = (fts3Hash *)sqlite3_user_data(context);
-
-  zName = sqlite3_value_text(argv[0]);
-  nName = sqlite3_value_bytes(argv[0])+1;
+  /* If the left hand side of the regexp operator is NULL, 
+  ** then the result is also NULL. 
+  */
+  if( !zString ){
+    return;
+  }
 
-  if( argc==2 ){
-    void *pOld;
-    int n = sqlite3_value_bytes(argv[1]);
-    if( n!=sizeof(pPtr) ){
-      sqlite3_result_error(context, "argument type mismatch", -1);
-      return;
-    }
-    pPtr = *(void **)sqlite3_value_blob(argv[1]);
-    pOld = sqlite3Fts3HashInsert(pHash, (void *)zName, nName, pPtr);
-    if( pOld==pPtr ){
-      sqlite3_result_error(context, "out of memory", -1);
+  pExpr = sqlite3_get_auxdata(p, 0);
+  if( !pExpr ){
+    const UChar *zPattern = sqlite3_value_text16(apArg[0]);
+    if( !zPattern ){
       return;
     }
-  }else{
-    pPtr = sqlite3Fts3HashFind(pHash, zName, nName);
-    if( !pPtr ){
-      char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
-      sqlite3_result_error(context, zErr, -1);
-      sqlite3_free(zErr);
+    pExpr = uregex_open(zPattern, -1, 0, 0, &status);
+
+    if( U_SUCCESS(status) ){
+      sqlite3_set_auxdata(p, 0, pExpr, icuRegexpDelete);
+    }else{
+      assert(!pExpr);
+      icuFunctionError(p, "uregex_open", status);
       return;
     }
   }
 
-  sqlite3_result_blob(context, (void *)&pPtr, sizeof(pPtr), SQLITE_TRANSIENT);
-}
+  /* Configure the text that the regular expression operates on. */
+  uregex_setText(pExpr, zString, -1, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "uregex_setText", status);
+    return;
+  }
 
-#ifdef SQLITE_TEST
+  /* Attempt the match */
+  res = uregex_matches(pExpr, 0, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "uregex_matches", status);
+    return;
+  }
 
+  /* Set the text that the regular expression operates on to a NULL
+  ** pointer. This is not really necessary, but it is tidier than 
+  ** leaving the regular expression object configured with an invalid
+  ** pointer after this function returns.
+  */
+  uregex_setText(pExpr, 0, 0, &status);
+
+  /* Return 1 or 0. */
+  sqlite3_result_int(p, res ? 1 : 0);
+}
 
 /*
-** Implementation of a special SQL scalar function for testing tokenizers 
-** designed to be used in concert with the Tcl testing framework. This
-** function must be called with two arguments:
+** Implementations of scalar functions for case mapping - upper() and 
+** lower(). Function upper() converts its input to upper-case (ABC).
+** Function lower() converts to lower-case (abc).
 **
-**   SELECT <function-name>(<key-name>, <input-string>);
-**   SELECT <function-name>(<key-name>, <pointer>);
+** ICU provides two types of case mapping, "general" case mapping and
+** "language specific". Refer to ICU documentation for the differences
+** between the two.
 **
-** where <function-name> is the name passed as the second argument
-** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
-** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
+** To utilise "general" case mapping, the upper() or lower() scalar 
+** functions are invoked with one argument:
 **
-** The return value is a string that may be interpreted as a Tcl
-** list. For each token in the <input-string>, three elements are
-** added to the returned list. The first is the token position, the 
-** second is the token text (folded, stemmed, etc.) and the third is the
-** substring of <input-string> associated with the token. For example, 
-** using the built-in "simple" tokenizer:
+**     upper('ABC') -> 'abc'
+**     lower('abc') -> 'ABC'
 **
-**   SELECT fts_tokenizer_test('simple', 'I don't see how');
+** To access ICU "language specific" case mapping, upper() or lower()
+** should be invoked with two arguments. The second argument is the name
+** of the locale to use. Passing an empty string ("") or SQL NULL value
+** as the second argument is the same as invoking the 1 argument version
+** of upper() or lower().
 **
-** will return the string:
+**     lower('I', 'en_us') -> 'i'
+**     lower('I', 'tr_tr') -> 'ı' (small dotless i)
 **
-**   "{0 i I 1 dont don't 2 see see 3 how how}"
-**   
+** http://www.icu-project.org/userguide/posix.html#case_mappings
 */
-static void testFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  fts3Hash *pHash;
-  sqlite3_tokenizer_module *p;
-  sqlite3_tokenizer *pTokenizer = 0;
-  sqlite3_tokenizer_cursor *pCsr = 0;
-
-  const char *zErr = 0;
-
-  const char *zName;
-  int nName;
-  const char *zInput;
+static void icuCaseFunc16(sqlite3_context *p, int nArg, sqlite3_value **apArg){
+  const UChar *zInput;
+  UChar *zOutput;
   int nInput;
+  int nOutput;
 
-  const char *zArg = 0;
-
-  const char *zToken;
-  int nToken;
-  int iStart;
-  int iEnd;
-  int iPos;
-
-  Tcl_Obj *pRet;
-
-  assert( argc==2 || argc==3 );
-
-  nName = sqlite3_value_bytes(argv[0]);
-  zName = (const char *)sqlite3_value_text(argv[0]);
-  nInput = sqlite3_value_bytes(argv[argc-1]);
-  zInput = (const char *)sqlite3_value_text(argv[argc-1]);
+  UErrorCode status = U_ZERO_ERROR;
+  const char *zLocale = 0;
 
-  if( argc==3 ){
-    zArg = (const char *)sqlite3_value_text(argv[1]);
+  assert(nArg==1 || nArg==2);
+  if( nArg==2 ){
+    zLocale = (const char *)sqlite3_value_text(apArg[1]);
   }
 
-  pHash = (fts3Hash *)sqlite3_user_data(context);
-  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
-
-  if( !p ){
-    char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
-    sqlite3_result_error(context, zErr, -1);
-    sqlite3_free(zErr);
+  zInput = sqlite3_value_text16(apArg[0]);
+  if( !zInput ){
     return;
   }
+  nInput = sqlite3_value_bytes16(apArg[0]);
 
-  pRet = Tcl_NewObj();
-  Tcl_IncrRefCount(pRet);
-
-  if( SQLITE_OK!=p->xCreate(zArg ? 1 : 0, &zArg, &pTokenizer) ){
-    zErr = "error in xCreate()";
-    goto finish;
-  }
-  pTokenizer->pModule = p;
-  if( SQLITE_OK!=p->xOpen(pTokenizer, zInput, nInput, &pCsr) ){
-    zErr = "error in xOpen()";
-    goto finish;
-  }
-  pCsr->pTokenizer = pTokenizer;
-
-  while( SQLITE_OK==p->xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
-    zToken = &zInput[iStart];
-    nToken = iEnd-iStart;
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
-  }
-
-  if( SQLITE_OK!=p->xClose(pCsr) ){
-    zErr = "error in xClose()";
-    goto finish;
-  }
-  if( SQLITE_OK!=p->xDestroy(pTokenizer) ){
-    zErr = "error in xDestroy()";
-    goto finish;
+  nOutput = nInput * 2 + 2;
+  zOutput = sqlite3_malloc(nOutput);
+  if( !zOutput ){
+    return;
   }
 
-finish:
-  if( zErr ){
-    sqlite3_result_error(context, zErr, -1);
+  if( sqlite3_user_data(p) ){
+    u_strToUpper(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status);
   }else{
-    sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
+    u_strToLower(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status);
   }
-  Tcl_DecrRefCount(pRet);
-}
-
-static
-int registerTokenizer(
-  sqlite3 *db, 
-  char *zName, 
-  const sqlite3_tokenizer_module *p
-){
-  int rc;
-  sqlite3_stmt *pStmt;
-  const char zSql[] = "SELECT fts3_tokenizer(?, ?)";
 
-  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "u_strToLower()/u_strToUpper", status);
+    return;
   }
 
-  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
-  sqlite3_bind_blob(pStmt, 2, &p, sizeof(p), SQLITE_STATIC);
-  sqlite3_step(pStmt);
+  sqlite3_result_text16(p, zOutput, -1, xFree);
+}
 
-  return sqlite3_finalize(pStmt);
+/*
+** Collation sequence destructor function. The pCtx argument points to
+** a UCollator structure previously allocated using ucol_open().
+*/
+static void icuCollationDel(void *pCtx){
+  UCollator *p = (UCollator *)pCtx;
+  ucol_close(p);
 }
 
-static
-int queryTokenizer(
-  sqlite3 *db, 
-  char *zName,  
-  const sqlite3_tokenizer_module **pp
+/*
+** Collation sequence comparison function. The pCtx argument points to
+** a UCollator structure previously allocated using ucol_open().
+*/
+static int icuCollationColl(
+  void *pCtx,
+  int nLeft,
+  const void *zLeft,
+  int nRight,
+  const void *zRight
 ){
-  int rc;
-  sqlite3_stmt *pStmt;
-  const char zSql[] = "SELECT fts3_tokenizer(?)";
-
-  *pp = 0;
-  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-
-  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
-  if( SQLITE_ROW==sqlite3_step(pStmt) ){
-    if( sqlite3_column_type(pStmt, 0)==SQLITE_BLOB ){
-      memcpy(pp, sqlite3_column_blob(pStmt, 0), sizeof(*pp));
-    }
-  }
-
-  return sqlite3_finalize(pStmt);
+  UCollationResult res;
+  UCollator *p = (UCollator *)pCtx;
+  res = ucol_strcoll(p, (UChar *)zLeft, nLeft/2, (UChar *)zRight, nRight/2);
+  switch( res ){
+    case UCOL_LESS:    return -1;
+    case UCOL_GREATER: return +1;
+    case UCOL_EQUAL:   return 0;
+  }
+  assert(!"Unexpected return value from ucol_strcoll()");
+  return 0;
 }
 
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-
 /*
-** Implementation of the scalar function fts3_tokenizer_internal_test().
-** This function is used for testing only, it is not included in the
-** build unless SQLITE_TEST is defined.
-**
-** The purpose of this is to test that the fts3_tokenizer() function
-** can be used as designed by the C-code in the queryTokenizer and
-** registerTokenizer() functions above. These two functions are repeated
-** in the README.tokenizer file as an example, so it is important to
-** test them.
+** Implementation of the scalar function icu_load_collation().
 **
-** To run the tests, evaluate the fts3_tokenizer_internal_test() scalar
-** function with no arguments. An assert() will fail if a problem is
-** detected. i.e.:
+** This scalar function is used to add ICU collation based collation 
+** types to an SQLite database connection. It is intended to be called
+** as follows:
 **
-**     SELECT fts3_tokenizer_internal_test();
+**     SELECT icu_load_collation(<locale>, <collation-name>);
 **
+** Where <locale> is a string containing an ICU locale identifier (i.e.
+** "en_AU", "tr_TR" etc.) and <collation-name> is the name of the
+** collation sequence to create.
 */
-static void intTestFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+static void icuLoadCollation(
+  sqlite3_context *p, 
+  int nArg, 
+  sqlite3_value **apArg
 ){
-  int rc;
-  const sqlite3_tokenizer_module *p1;
-  const sqlite3_tokenizer_module *p2;
-  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-
-  /* Test the query function */
-  sqlite3Fts3SimpleTokenizerModule(&p1);
-  rc = queryTokenizer(db, "simple", &p2);
-  assert( rc==SQLITE_OK );
-  assert( p1==p2 );
-  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
-  assert( rc==SQLITE_ERROR );
-  assert( p2==0 );
-  assert( 0==strcmp(sqlite3_errmsg(db), "unknown tokenizer: nosuchtokenizer") );
+  sqlite3 *db = (sqlite3 *)sqlite3_user_data(p);
+  UErrorCode status = U_ZERO_ERROR;
+  const char *zLocale;      /* Locale identifier - (eg. "jp_JP") */
+  const char *zName;        /* SQL Collation sequence name (eg. "japanese") */
+  UCollator *pUCollator;    /* ICU library collation object */
+  int rc;                   /* Return code from sqlite3_create_collation_x() */
+
+  assert(nArg==2);
+  zLocale = (const char *)sqlite3_value_text(apArg[0]);
+  zName = (const char *)sqlite3_value_text(apArg[1]);
+
+  if( !zLocale || !zName ){
+    return;
+  }
 
-  /* Test the storage function */
-  rc = registerTokenizer(db, "nosuchtokenizer", p1);
-  assert( rc==SQLITE_OK );
-  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
-  assert( rc==SQLITE_OK );
-  assert( p2==p1 );
+  pUCollator = ucol_open(zLocale, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "ucol_open", status);
+    return;
+  }
+  assert(p);
 
-  sqlite3_result_text(context, "ok", -1, SQLITE_STATIC);
+  rc = sqlite3_create_collation_v2(db, zName, SQLITE_UTF16, (void *)pUCollator, 
+      icuCollationColl, icuCollationDel
+  );
+  if( rc!=SQLITE_OK ){
+    ucol_close(pUCollator);
+    sqlite3_result_error(p, "Error registering collation function", -1);
+  }
 }
 
-#endif
-
 /*
-** Set up SQL objects in database db used to access the contents of
-** the hash table pointed to by argument pHash. The hash table must
-** been initialised to use string keys, and to take a private copy 
-** of the key when a value is inserted. i.e. by a call similar to:
-**
-**    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
-**
-** This function adds a scalar function (see header comment above
-** scalarFunc() in this file for details) and, if ENABLE_TABLE is
-** defined at compilation time, a temporary virtual table (see header 
-** comment above struct HashTableVtab) to the database schema. Both 
-** provide read/write access to the contents of *pHash.
-**
-** The third argument to this function, zName, is used as the name
-** of both the scalar and, if created, the virtual table.
+** Register the ICU extension functions with database db.
 */
-SQLITE_PRIVATE int sqlite3Fts3InitHashTable(
-  sqlite3 *db, 
-  fts3Hash *pHash, 
-  const char *zName
-){
+SQLITE_PRIVATE int sqlite3IcuInit(sqlite3 *db){
+  struct IcuScalar {
+    const char *zName;                        /* Function name */
+    int nArg;                                 /* Number of arguments */
+    int enc;                                  /* Optimal text encoding */
+    void *pContext;                           /* sqlite3_user_data() context */
+    void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
+  } scalars[] = {
+    {"regexp",-1, SQLITE_ANY,          0, icuRegexpFunc},
+
+    {"lower",  1, SQLITE_UTF16,        0, icuCaseFunc16},
+    {"lower",  2, SQLITE_UTF16,        0, icuCaseFunc16},
+    {"upper",  1, SQLITE_UTF16, (void*)1, icuCaseFunc16},
+    {"upper",  2, SQLITE_UTF16, (void*)1, icuCaseFunc16},
+
+    {"lower",  1, SQLITE_UTF8,         0, icuCaseFunc16},
+    {"lower",  2, SQLITE_UTF8,         0, icuCaseFunc16},
+    {"upper",  1, SQLITE_UTF8,  (void*)1, icuCaseFunc16},
+    {"upper",  2, SQLITE_UTF8,  (void*)1, icuCaseFunc16},
+
+    {"like",   2, SQLITE_UTF8,         0, icuLikeFunc},
+    {"like",   3, SQLITE_UTF8,         0, icuLikeFunc},
+
+    {"icu_load_collation",  2, SQLITE_UTF8, (void*)db, icuLoadCollation},
+  };
+
   int rc = SQLITE_OK;
-  void *p = (void *)pHash;
-  const int any = SQLITE_ANY;
-  char *zTest = 0;
-  char *zTest2 = 0;
+  int i;
 
-#ifdef SQLITE_TEST
-  void *pdb = (void *)db;
-  zTest = sqlite3_mprintf("%s_test", zName);
-  zTest2 = sqlite3_mprintf("%s_internal_test", zName);
-  if( !zTest || !zTest2 ){
-    rc = SQLITE_NOMEM;
+  for(i=0; rc==SQLITE_OK && i<(sizeof(scalars)/sizeof(struct IcuScalar)); i++){
+    struct IcuScalar *p = &scalars[i];
+    rc = sqlite3_create_function(
+        db, p->zName, p->nArg, p->enc, p->pContext, p->xFunc, 0, 0
+    );
   }
-#endif
-
-  if( rc!=SQLITE_OK
-   || (rc = sqlite3_create_function(db, zName, 1, any, p, scalarFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zName, 2, any, p, scalarFunc, 0, 0))
-#ifdef SQLITE_TEST
-   || (rc = sqlite3_create_function(db, zTest, 2, any, p, testFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zTest, 3, any, p, testFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zTest2, 0, any, pdb, intTestFunc, 0, 0))
-#endif
-  );
 
-  sqlite3_free(zTest);
-  sqlite3_free(zTest2);
   return rc;
 }
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db, 
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
+){
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3IcuInit(db);
+}
+#endif
 
-/************** End of fts3_tokenizer.c **************************************/
-/************** Begin file fts3_tokenizer1.c *********************************/
+#endif
+
+/************** End of icu.c *************************************************/
+/************** Begin file fts3_icu.c ****************************************/
 /*
-** 2006 Oct 10
+** 2007 June 22
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -86818,94 +110360,77 @@ SQLITE_PRIVATE int sqlite3Fts3InitHashTable(
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-******************************************************************************
-**
-** Implementation of the "simple" full-text-search tokenizer.
+*************************************************************************
+** This file implements a tokenizer for fts3 based on the ICU library.
+** 
+** $Id: fts3_icu.c,v 1.3 2008/09/01 18:34:20 danielk1977 Exp $
 */
 
-/*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
-*/
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+#ifdef SQLITE_ENABLE_ICU
 
 
+#include <unicode/ubrk.h>
+#include <unicode/utf16.h>
 
+typedef struct IcuTokenizer IcuTokenizer;
+typedef struct IcuCursor IcuCursor;
 
-typedef struct simple_tokenizer {
+struct IcuTokenizer {
   sqlite3_tokenizer base;
-  char delim[128];             /* flag ASCII delimiters */
-} simple_tokenizer;
+  char *zLocale;
+};
 
-typedef struct simple_tokenizer_cursor {
+struct IcuCursor {
   sqlite3_tokenizer_cursor base;
-  const char *pInput;          /* input we are tokenizing */
-  int nBytes;                  /* size of the input */
-  int iOffset;                 /* current position in pInput */
-  int iToken;                  /* index of next token to be returned */
-  char *pToken;                /* storage for current token */
-  int nTokenAllocated;         /* space allocated to zToken buffer */
-} simple_tokenizer_cursor;
 
+  UBreakIterator *pIter;      /* ICU break-iterator object */
+  int nChar;                  /* Number of UChar elements in pInput */
+  UChar *aChar;               /* Copy of input using utf-16 encoding */
+  int *aOffset;               /* Offsets of each character in utf-8 input */
 
-/* Forward declaration */
-static const sqlite3_tokenizer_module simpleTokenizerModule;
+  int nBuffer;
+  char *zBuffer;
 
-static int simpleDelim(simple_tokenizer *t, unsigned char c){
-  return c<0x80 && t->delim[c];
-}
+  int iToken;
+};
 
 /*
 ** Create a new tokenizer instance.
 */
-static int simpleCreate(
-  int argc, const char * const *argv,
-  sqlite3_tokenizer **ppTokenizer
+static int icuCreate(
+  int argc,                            /* Number of entries in argv[] */
+  const char * const *argv,            /* Tokenizer creation arguments */
+  sqlite3_tokenizer **ppTokenizer      /* OUT: Created tokenizer */
 ){
-  simple_tokenizer *t;
+  IcuTokenizer *p;
+  int n = 0;
 
-  t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
-  if( t==NULL ) return SQLITE_NOMEM;
-  memset(t, 0, sizeof(*t));
+  if( argc>0 ){
+    n = strlen(argv[0])+1;
+  }
+  p = (IcuTokenizer *)sqlite3_malloc(sizeof(IcuTokenizer)+n);
+  if( !p ){
+    return SQLITE_NOMEM;
+  }
+  memset(p, 0, sizeof(IcuTokenizer));
 
-  /* TODO(shess) Delimiters need to remain the same from run to run,
-  ** else we need to reindex.  One solution would be a meta-table to
-  ** track such information in the database, then we'd only want this
-  ** information on the initial create.
-  */
-  if( argc>1 ){
-    int i, n = strlen(argv[1]);
-    for(i=0; i<n; i++){
-      unsigned char ch = argv[1][i];
-      /* We explicitly don't support UTF-8 delimiters for now. */
-      if( ch>=0x80 ){
-        sqlite3_free(t);
-        return SQLITE_ERROR;
-      }
-      t->delim[ch] = 1;
-    }
-  } else {
-    /* Mark non-alphanumeric ASCII characters as delimiters */
-    int i;
-    for(i=1; i<0x80; i++){
-      t->delim[i] = !isalnum(i);
-    }
+  if( n ){
+    p->zLocale = (char *)&p[1];
+    memcpy(p->zLocale, argv[0], n);
   }
 
-  *ppTokenizer = &t->base;
+  *ppTokenizer = (sqlite3_tokenizer *)p;
+
   return SQLITE_OK;
 }
 
 /*
 ** Destroy a tokenizer
 */
-static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
-  sqlite3_free(pTokenizer);
+static int icuDestroy(sqlite3_tokenizer *pTokenizer){
+  IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
+  sqlite3_free(p);
   return SQLITE_OK;
 }
 
@@ -86915,49 +110440,87 @@ static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
 ** used to incrementally tokenize this string is returned in 
 ** *ppCursor.
 */
-static int simpleOpen(
+static int icuOpen(
   sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
-  const char *pInput, int nBytes,        /* String to be tokenized */
+  const char *zInput,                    /* Input string */
+  int nInput,                            /* Length of zInput in bytes */
   sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
 ){
-  simple_tokenizer_cursor *c;
+  IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
+  IcuCursor *pCsr;
 
-  c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
-  if( c==NULL ) return SQLITE_NOMEM;
+  const int32_t opt = U_FOLD_CASE_DEFAULT;
+  UErrorCode status = U_ZERO_ERROR;
+  int nChar;
 
-  c->pInput = pInput;
-  if( pInput==0 ){
-    c->nBytes = 0;
-  }else if( nBytes<0 ){
-    c->nBytes = (int)strlen(pInput);
-  }else{
-    c->nBytes = nBytes;
+  UChar32 c;
+  int iInput = 0;
+  int iOut = 0;
+
+  *ppCursor = 0;
+
+  if( nInput<0 ){
+    nInput = strlen(zInput);
   }
-  c->iOffset = 0;                 /* start tokenizing at the beginning */
-  c->iToken = 0;
-  c->pToken = NULL;               /* no space allocated, yet. */
-  c->nTokenAllocated = 0;
+  nChar = nInput+1;
+  pCsr = (IcuCursor *)sqlite3_malloc(
+      sizeof(IcuCursor) +                /* IcuCursor */
+      nChar * sizeof(UChar) +            /* IcuCursor.aChar[] */
+      (nChar+1) * sizeof(int)            /* IcuCursor.aOffset[] */
+  );
+  if( !pCsr ){
+    return SQLITE_NOMEM;
+  }
+  memset(pCsr, 0, sizeof(IcuCursor));
+  pCsr->aChar = (UChar *)&pCsr[1];
+  pCsr->aOffset = (int *)&pCsr->aChar[nChar];
+
+  pCsr->aOffset[iOut] = iInput;
+  U8_NEXT(zInput, iInput, nInput, c); 
+  while( c>0 ){
+    int isError = 0;
+    c = u_foldCase(c, opt);
+    U16_APPEND(pCsr->aChar, iOut, nChar, c, isError);
+    if( isError ){
+      sqlite3_free(pCsr);
+      return SQLITE_ERROR;
+    }
+    pCsr->aOffset[iOut] = iInput;
 
-  *ppCursor = &c->base;
+    if( iInput<nInput ){
+      U8_NEXT(zInput, iInput, nInput, c);
+    }else{
+      c = 0;
+    }
+  }
+
+  pCsr->pIter = ubrk_open(UBRK_WORD, p->zLocale, pCsr->aChar, iOut, &status);
+  if( !U_SUCCESS(status) ){
+    sqlite3_free(pCsr);
+    return SQLITE_ERROR;
+  }
+  pCsr->nChar = iOut;
+
+  ubrk_first(pCsr->pIter);
+  *ppCursor = (sqlite3_tokenizer_cursor *)pCsr;
   return SQLITE_OK;
 }
 
 /*
-** Close a tokenization cursor previously opened by a call to
-** simpleOpen() above.
+** Close a tokenization cursor previously opened by a call to icuOpen().
 */
-static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
-  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
-  sqlite3_free(c->pToken);
-  sqlite3_free(c);
+static int icuClose(sqlite3_tokenizer_cursor *pCursor){
+  IcuCursor *pCsr = (IcuCursor *)pCursor;
+  ubrk_close(pCsr->pIter);
+  sqlite3_free(pCsr->zBuffer);
+  sqlite3_free(pCsr);
   return SQLITE_OK;
 }
 
 /*
-** Extract the next token from a tokenization cursor.  The cursor must
-** have been opened by a prior call to simpleOpen().
+** Extract the next token from a tokenization cursor.
 */
-static int simpleNext(
+static int icuNext(
   sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by simpleOpen */
   const char **ppToken,               /* OUT: *ppToken is the token text */
   int *pnBytes,                       /* OUT: Number of bytes in token */
@@ -86965,72 +110528,82 @@ static int simpleNext(
   int *piEndOffset,                   /* OUT: Ending offset of token */
   int *piPosition                     /* OUT: Position integer of token */
 ){
-  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
-  simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer;
-  unsigned char *p = (unsigned char *)c->pInput;
+  IcuCursor *pCsr = (IcuCursor *)pCursor;
 
-  while( c->iOffset<c->nBytes ){
-    int iStartOffset;
+  int iStart = 0;
+  int iEnd = 0;
+  int nByte = 0;
 
-    /* Scan past delimiter characters */
-    while( c->iOffset<c->nBytes && simpleDelim(t, p[c->iOffset]) ){
-      c->iOffset++;
-    }
+  while( iStart==iEnd ){
+    UChar32 c;
 
-    /* Count non-delimiter characters. */
-    iStartOffset = c->iOffset;
-    while( c->iOffset<c->nBytes && !simpleDelim(t, p[c->iOffset]) ){
-      c->iOffset++;
+    iStart = ubrk_current(pCsr->pIter);
+    iEnd = ubrk_next(pCsr->pIter);
+    if( iEnd==UBRK_DONE ){
+      return SQLITE_DONE;
     }
 
-    if( c->iOffset>iStartOffset ){
-      int i, n = c->iOffset-iStartOffset;
-      if( n>c->nTokenAllocated ){
-        c->nTokenAllocated = n+20;
-        c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
-        if( c->pToken==NULL ) return SQLITE_NOMEM;
-      }
-      for(i=0; i<n; i++){
-        /* TODO(shess) This needs expansion to handle UTF-8
-        ** case-insensitivity.
-        */
-        unsigned char ch = p[iStartOffset+i];
-        c->pToken[i] = ch<0x80 ? tolower(ch) : ch;
+    while( iStart<iEnd ){
+      int iWhite = iStart;
+      U8_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
+      if( u_isspace(c) ){
+        iStart = iWhite;
+      }else{
+        break;
       }
-      *ppToken = c->pToken;
-      *pnBytes = n;
-      *piStartOffset = iStartOffset;
-      *piEndOffset = c->iOffset;
-      *piPosition = c->iToken++;
-
-      return SQLITE_OK;
     }
+    assert(iStart<=iEnd);
   }
-  return SQLITE_DONE;
+
+  do {
+    UErrorCode status = U_ZERO_ERROR;
+    if( nByte ){
+      char *zNew = sqlite3_realloc(pCsr->zBuffer, nByte);
+      if( !zNew ){
+        return SQLITE_NOMEM;
+      }
+      pCsr->zBuffer = zNew;
+      pCsr->nBuffer = nByte;
+    }
+
+    u_strToUTF8(
+        pCsr->zBuffer, pCsr->nBuffer, &nByte,    /* Output vars */
+        &pCsr->aChar[iStart], iEnd-iStart,       /* Input vars */
+        &status                                  /* Output success/failure */
+    );
+  } while( nByte>pCsr->nBuffer );
+
+  *ppToken = pCsr->zBuffer;
+  *pnBytes = nByte;
+  *piStartOffset = pCsr->aOffset[iStart];
+  *piEndOffset = pCsr->aOffset[iEnd];
+  *piPosition = pCsr->iToken++;
+
+  return SQLITE_OK;
 }
 
 /*
 ** The set of routines that implement the simple tokenizer
 */
-static const sqlite3_tokenizer_module simpleTokenizerModule = {
-  0,
-  simpleCreate,
-  simpleDestroy,
-  simpleOpen,
-  simpleClose,
-  simpleNext,
+static const sqlite3_tokenizer_module icuTokenizerModule = {
+  0,                           /* iVersion */
+  icuCreate,                   /* xCreate  */
+  icuDestroy,                  /* xCreate  */
+  icuOpen,                     /* xOpen    */
+  icuClose,                    /* xClose   */
+  icuNext,                     /* xNext    */
 };
 
 /*
-** Allocate a new simple tokenizer.  Return a pointer to the new
-** tokenizer in *ppModule
+** Set *ppModule to point at the implementation of the ICU tokenizer.
 */
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(
+SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(
   sqlite3_tokenizer_module const**ppModule
 ){
-  *ppModule = &simpleTokenizerModule;
+  *ppModule = &icuTokenizerModule;
 }
 
+#endif /* defined(SQLITE_ENABLE_ICU) */
 #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-/************** End of fts3_tokenizer1.c *************************************/
+/************** End of fts3_icu.c ********************************************/
diff --git a/src/3rdparty/sqlite/sqlite3.h b/src/3rdparty/sqlite/sqlite3.h
index a492b6d..5216154 100644
--- a/src/3rdparty/sqlite/sqlite3.h
+++ b/src/3rdparty/sqlite/sqlite3.h
@@ -17,9 +17,9 @@
 **
 ** Some of the definitions that are in this file are marked as
 ** "experimental".  Experimental interfaces are normally new
-** features recently added to SQLite.  We do not anticipate changes 
-** to experimental interfaces but reserve to make minor changes if
-** experience from use "in the wild" suggest such changes are prudent.
+** features recently added to SQLite.  We do not anticipate changes
+** to experimental interfaces but reserve the right to make minor changes
+** if experience from use "in the wild" suggest such changes are prudent.
 **
 ** The official C-language API documentation for SQLite is derived
 ** from comments in this file.  This file is the authoritative source
@@ -29,8 +29,6 @@
 ** The makefile makes some minor changes to this file (such as inserting
 ** the version number) and changes its name to "sqlite3.h" as
 ** part of the build process.
-**
-** @(#) $Id: sqlite.h.in,v 1.312 2008/05/12 12:39:56 drh Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
@@ -51,9 +49,29 @@ extern "C" {
 # define SQLITE_EXTERN extern
 #endif
 
+#ifndef SQLITE_API
+# define SQLITE_API
+#endif
+
+
 /*
-** Make sure these symbols where not defined by some previous header
-** file.
+** These no-op macros are used in front of interfaces to mark those
+** interfaces as either deprecated or experimental.  New applications
+** should not use deprecated interfaces - they are support for backwards
+** compatibility only.  Application writers should be aware that
+** experimental interfaces are subject to change in point releases.
+**
+** These macros used to resolve to various kinds of compiler magic that
+** would generate warning messages when they were used.  But that
+** compiler magic ended up generating such a flurry of bug reports
+** that we have taken it all out and gone back to using simple
+** noop macros.
+*/
+#define SQLITE_DEPRECATED
+#define SQLITE_EXPERIMENTAL
+
+/*
+** Ensure these symbols were not defined by some previous header file.
 */
 #ifdef SQLITE_VERSION
 # undef SQLITE_VERSION
@@ -63,130 +81,143 @@ extern "C" {
 #endif
 
 /*
-** CAPI3REF: Compile-Time Library Version Numbers {F10010}
+** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
 **
 ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
 ** the sqlite3.h file specify the version of SQLite with which
 ** that header file is associated.
 **
-** The "version" of SQLite is a string of the form "X.Y.Z".
-** The phrase "alpha" or "beta" might be appended after the Z.
-** The X value is major version number always 3 in SQLite3.
-** The X value only changes when  backwards compatibility is
-** broken and we intend to never break
-** backwards compatibility.  The Y value is the minor version
-** number and only changes when
+** The "version" of SQLite is a string of the form "W.X.Y" or "W.X.Y.Z".
+** The W value is major version number and is always 3 in SQLite3.
+** The W value only changes when backwards compatibility is
+** broken and we intend to never break backwards compatibility.
+** The X value is the minor version number and only changes when
 ** there are major feature enhancements that are forwards compatible
-** but not backwards compatible.  The Z value is release number
-** and is incremented with
-** each release but resets back to 0 when Y is incremented.
+** but not backwards compatible.
+** The Y value is the release number and is incremented with
+** each release but resets back to 0 whenever X is incremented.
+** The Z value only appears on branch releases.
+**
+** The SQLITE_VERSION_NUMBER is an integer that is computed as
+** follows:
 **
-** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
+** <blockquote><pre>
+** SQLITE_VERSION_NUMBER = W*1000000 + X*1000 + Y
+** </pre></blockquote>
 **
-** INVARIANTS:
+** Since version 3.6.18, SQLite source code has been stored in the
+** <a href="http://www.fossil-scm.org/">fossil configuration management
+** system</a>.  The SQLITE_SOURCE_ID
+** macro is a string which identifies a particular check-in of SQLite
+** within its configuration management system.  The string contains the
+** date and time of the check-in (UTC) and an SHA1 hash of the entire
+** source tree.
 **
-** {F10011} The SQLITE_VERSION #define in the sqlite3.h header file
-**          evaluates to a string literal that is the SQLite version
-**          with which the header file is associated.
+** See also: [sqlite3_libversion()],
+** [sqlite3_libversion_number()], [sqlite3_sourceid()],
+** [sqlite_version()] and [sqlite_source_id()].
 **
-** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer
-**          with the value  (X*1000000 + Y*1000 + Z) where X, Y, and
-**          Z are the major version, minor version, and release number.
+** Requirements: [H10011] [H10014]
 */
-#define SQLITE_VERSION         "3.5.9"
-#define SQLITE_VERSION_NUMBER  3005009
+#define SQLITE_VERSION        "3.6.19"
+#define SQLITE_VERSION_NUMBER 3006019
+#define SQLITE_SOURCE_ID      "2009-10-14 11:33:55 c1d499afc50d54b376945b4efb65c56c787a073d"
 
 /*
-** CAPI3REF: Run-Time Library Version Numbers {F10020}
+** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
 ** KEYWORDS: sqlite3_version
 **
-** These features provide the same information as the [SQLITE_VERSION]
-** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
-** with the library instead of the header file.  Cautious programmers might
-** include a check in their application to verify that 
-** sqlite3_libversion_number() always returns the value 
-** [SQLITE_VERSION_NUMBER].
+** These interfaces provide the same information as the [SQLITE_VERSION],
+** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] #defines in the header,
+** but are associated with the library instead of the header file.  Cautious
+** programmers might include assert() statements in their application to
+** verify that values returned by these interfaces match the macros in
+** the header, and thus insure that the application is
+** compiled with matching library and header files.
+**
+** <blockquote><pre>
+** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
+** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
+** assert( strcmp(sqlite3_libversion,SQLITE_VERSION)==0 );
+** </pre></blockquote>
 **
 ** The sqlite3_libversion() function returns the same information as is
 ** in the sqlite3_version[] string constant.  The function is provided
 ** for use in DLLs since DLL users usually do not have direct access to string
-** constants within the DLL.
-**
-** INVARIANTS:
-**
-** {F10021} The [sqlite3_libversion_number()] interface returns an integer
-**          equal to [SQLITE_VERSION_NUMBER]. 
+** constants within the DLL.  Similarly, the sqlite3_sourceid() function
+** returns the same information as is in the [SQLITE_SOURCE_ID] #define of
+** the header file.
 **
-** {F10022} The [sqlite3_version] string constant contains the text of the
-**          [SQLITE_VERSION] string. 
+** See also: [sqlite_version()] and [sqlite_source_id()].
 **
-** {F10023} The [sqlite3_libversion()] function returns
-**          a pointer to the [sqlite3_version] string constant.
+** Requirements: [H10021] [H10022] [H10023]
 */
-SQLITE_EXTERN const char sqlite3_version[];
-const char *sqlite3_libversion(void);
-int sqlite3_libversion_number(void);
+SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
+SQLITE_API const char *sqlite3_libversion(void);
+SQLITE_API const char *sqlite3_sourceid(void);
+SQLITE_API int sqlite3_libversion_number(void);
 
 /*
-** CAPI3REF: Test To See If The Library Is Threadsafe {F10100}
+** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
 **
 ** SQLite can be compiled with or without mutexes.  When
-** the SQLITE_THREADSAFE C preprocessor macro is true, mutexes
-** are enabled and SQLite is threadsafe.  When that macro is false,
+** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
+** are enabled and SQLite is threadsafe.  When the
+** [SQLITE_THREADSAFE] macro is 0, 
 ** the mutexes are omitted.  Without the mutexes, it is not safe
-** to use SQLite from more than one thread.
+** to use SQLite concurrently from more than one thread.
 **
-** There is a measurable performance penalty for enabling mutexes.
+** Enabling mutexes incurs a measurable performance penalty.
 ** So if speed is of utmost importance, it makes sense to disable
 ** the mutexes.  But for maximum safety, mutexes should be enabled.
 ** The default behavior is for mutexes to be enabled.
 **
-** This interface can be used by a program to make sure that the
+** This interface can be used by an application to make sure that the
 ** version of SQLite that it is linking against was compiled with
-** the desired setting of the SQLITE_THREADSAFE macro.
+** the desired setting of the [SQLITE_THREADSAFE] macro.
 **
-** INVARIANTS:
+** This interface only reports on the compile-time mutex setting
+** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
+** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
+** can be fully or partially disabled using a call to [sqlite3_config()]
+** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
+** or [SQLITE_CONFIG_MUTEX].  The return value of this function shows
+** only the default compile-time setting, not any run-time changes
+** to that setting.
 **
-** {F10101} The [sqlite3_threadsafe()] function returns nonzero if
-**          SQLite was compiled with its mutexes enabled or zero
-**          if SQLite was compiled with mutexes disabled.
+** See the [threading mode] documentation for additional information.
+**
+** Requirements: [H10101] [H10102]
 */
-int sqlite3_threadsafe(void);
+SQLITE_API int sqlite3_threadsafe(void);
 
 /*
-** CAPI3REF: Database Connection Handle {F12000}
+** CAPI3REF: Database Connection Handle {H12000} <S40200>
 ** KEYWORDS: {database connection} {database connections}
 **
-** Each open SQLite database is represented by pointer to an instance of the
-** opaque structure named "sqlite3".  It is useful to think of an sqlite3
+** Each open SQLite database is represented by a pointer to an instance of
+** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
 ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
-** [sqlite3_open_v2()] interfaces are its constructors
-** and [sqlite3_close()] is its destructor.  There are many other interfaces
-** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and
-** [sqlite3_busy_timeout()] to name but three) that are methods on this
-** object.
+** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
+** is its destructor.  There are many other interfaces (such as
+** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
+** [sqlite3_busy_timeout()] to name but three) that are methods on an
+** sqlite3 object.
 */
 typedef struct sqlite3 sqlite3;
 
-
 /*
-** CAPI3REF: 64-Bit Integer Types {F10200}
+** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
 ** KEYWORDS: sqlite_int64 sqlite_uint64
 **
 ** Because there is no cross-platform way to specify 64-bit integer types
 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
 **
-** The sqlite3_int64 and sqlite3_uint64 are the preferred type
-** definitions.  The sqlite_int64 and sqlite_uint64 types are
-** supported for backwards compatibility only.
-**
-** INVARIANTS:
-**
-** {F10201} The [sqlite_int64] and [sqlite3_int64] types specify a
-**          64-bit signed integer.
+** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
+** The sqlite_int64 and sqlite_uint64 types are supported for backwards
+** compatibility only.
 **
-** {F10202} The [sqlite_uint64] and [sqlite3_uint64] types specify
-**          a 64-bit unsigned integer.
+** Requirements: [H10201] [H10202]
 */
 #ifdef SQLITE_INT64_TYPE
   typedef SQLITE_INT64_TYPE sqlite_int64;
@@ -203,52 +234,43 @@ typedef sqlite_uint64 sqlite3_uint64;
 
 /*
 ** If compiling for a processor that lacks floating point support,
-** substitute integer for floating-point
+** substitute integer for floating-point.
 */
 #ifdef SQLITE_OMIT_FLOATING_POINT
 # define double sqlite3_int64
 #endif
 
 /*
-** CAPI3REF: Closing A Database Connection {F12010}
-**
-** This routine is the destructor for the [sqlite3] object.  
-**
-** Applications should [sqlite3_finalize | finalize] all
-** [prepared statements] and
-** [sqlite3_blob_close | close] all [sqlite3_blob | BLOBs] 
-** associated with the [sqlite3] object prior
-** to attempting to close the [sqlite3] object.
-**
-** <todo>What happens to pending transactions?  Are they
-** rolled back, or abandoned?</todo>
-**
-** INVARIANTS:
+** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
 **
-** {F12011} The [sqlite3_close()] interface destroys an [sqlite3] object
-**          allocated by a prior call to [sqlite3_open()],
-**          [sqlite3_open16()], or [sqlite3_open_v2()].
+** This routine is the destructor for the [sqlite3] object.
 **
-** {F12012} The [sqlite3_close()] function releases all memory used by the
-**          connection and closes all open files.
+** Applications should [sqlite3_finalize | finalize] all [prepared statements]
+** and [sqlite3_blob_close | close] all [BLOB handles] associated with
+** the [sqlite3] object prior to attempting to close the object.
+** The [sqlite3_next_stmt()] interface can be used to locate all
+** [prepared statements] associated with a [database connection] if desired.
+** Typical code might look like this:
 **
-** {F12013} If the database connection contains
-**          [prepared statements] that have not been
-**          finalized by [sqlite3_finalize()], then [sqlite3_close()]
-**          returns [SQLITE_BUSY] and leaves the connection open.
-**
-** {F12014} Giving sqlite3_close() a NULL pointer is a harmless no-op.
+** <blockquote><pre>
+** sqlite3_stmt *pStmt;
+** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
+** &nbsp;   sqlite3_finalize(pStmt);
+** }
+** </pre></blockquote>
 **
-** LIMITATIONS:
+** If [sqlite3_close()] is invoked while a transaction is open,
+** the transaction is automatically rolled back.
 **
-** {U12015} The parameter to [sqlite3_close()] must be an [sqlite3] object
-**          pointer previously obtained from [sqlite3_open()] or the 
-**          equivalent, or NULL.
+** The C parameter to [sqlite3_close(C)] must be either a NULL
+** pointer or an [sqlite3] object pointer obtained
+** from [sqlite3_open()], [sqlite3_open16()], or
+** [sqlite3_open_v2()], and not previously closed.
 **
-** {U12016} The parameter to [sqlite3_close()] must not have been previously
-**          closed.
+** Requirements:
+** [H12011] [H12012] [H12013] [H12014] [H12015] [H12019]
 */
-int sqlite3_close(sqlite3 *);
+SQLITE_API int sqlite3_close(sqlite3 *);
 
 /*
 ** The type for a callback function.
@@ -258,115 +280,67 @@ int sqlite3_close(sqlite3 *);
 typedef int (*sqlite3_callback)(void*,int,char**, char**);
 
 /*
-** CAPI3REF: One-Step Query Execution Interface {F12100}
-**
-** The sqlite3_exec() interface is a convenient way of running
-** one or more SQL statements without a lot of C code.  The
-** SQL statements are passed in as the second parameter to
-** sqlite3_exec().  The statements are evaluated one by one
-** until either an error or an interrupt is encountered or
-** until they are all done.  The 3rd parameter is an optional
-** callback that is invoked once for each row of any query results
-** produced by the SQL statements.  The 5th parameter tells where
+** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
+**
+** The sqlite3_exec() interface is a convenient way of running one or more
+** SQL statements without having to write a lot of C code.  The UTF-8 encoded
+** SQL statements are passed in as the second parameter to sqlite3_exec().
+** The statements are evaluated one by one until either an error or
+** an interrupt is encountered, or until they are all done.  The 3rd parameter
+** is an optional callback that is invoked once for each row of any query
+** results produced by the SQL statements.  The 5th parameter tells where
 ** to write any error messages.
 **
+** The error message passed back through the 5th parameter is held
+** in memory obtained from [sqlite3_malloc()].  To avoid a memory leak,
+** the calling application should call [sqlite3_free()] on any error
+** message returned through the 5th parameter when it has finished using
+** the error message.
+**
+** If the SQL statement in the 2nd parameter is NULL or an empty string
+** or a string containing only whitespace and comments, then no SQL
+** statements are evaluated and the database is not changed.
+**
 ** The sqlite3_exec() interface is implemented in terms of
 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
-** The sqlite3_exec() routine does nothing that cannot be done
+** The sqlite3_exec() routine does nothing to the database that cannot be done
 ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
-** The sqlite3_exec() is just a convenient wrapper.
-**
-** INVARIANTS:
-** 
-** {F12101} The [sqlite3_exec()] interface evaluates zero or more UTF-8
-**          encoded, semicolon-separated, SQL statements in the
-**          zero-terminated string of its 2nd parameter within the
-**          context of the [sqlite3] object given in the 1st parameter.
 **
-** {F12104} The return value of [sqlite3_exec()] is SQLITE_OK if all
-**          SQL statements run successfully.
+** The first parameter to [sqlite3_exec()] must be an valid and open
+** [database connection].
 **
-** {F12105} The return value of [sqlite3_exec()] is an appropriate 
-**          non-zero error code if any SQL statement fails.
+** The database connection must not be closed while
+** [sqlite3_exec()] is running.
 **
-** {F12107} If one or more of the SQL statements handed to [sqlite3_exec()]
-**          return results and the 3rd parameter is not NULL, then
-**          the callback function specified by the 3rd parameter is
-**          invoked once for each row of result.
+** The calling function should use [sqlite3_free()] to free
+** the memory that *errmsg is left pointing at once the error
+** message is no longer needed.
 **
-** {F12110} If the callback returns a non-zero value then [sqlite3_exec()]
-**          will aborted the SQL statement it is currently evaluating,
-**          skip all subsequent SQL statements, and return [SQLITE_ABORT].
-**          <todo>What happens to *errmsg here?  Does the result code for
-**          sqlite3_errcode() get set?</todo>
+** The SQL statement text in the 2nd parameter to [sqlite3_exec()]
+** must remain unchanged while [sqlite3_exec()] is running.
 **
-** {F12113} The [sqlite3_exec()] routine will pass its 4th parameter through
-**          as the 1st parameter of the callback.
-**
-** {F12116} The [sqlite3_exec()] routine sets the 2nd parameter of its
-**          callback to be the number of columns in the current row of
-**          result.
-**
-** {F12119} The [sqlite3_exec()] routine sets the 3rd parameter of its 
-**          callback to be an array of pointers to strings holding the
-**          values for each column in the current result set row as
-**          obtained from [sqlite3_column_text()].
-**
-** {F12122} The [sqlite3_exec()] routine sets the 4th parameter of its
-**          callback to be an array of pointers to strings holding the
-**          names of result columns as obtained from [sqlite3_column_name()].
-**
-** {F12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
-**          [sqlite3_exec()] never invokes a callback.  All query
-**          results are silently discarded.
-**
-** {F12128} If an error occurs while parsing or evaluating any of the SQL
-**          statements handed to [sqlite3_exec()] then [sqlite3_exec()] will
-**          return an [error code] other than [SQLITE_OK].
-**
-** {F12131} If an error occurs while parsing or evaluating any of the SQL
-**          handed to [sqlite3_exec()] and if the 5th parameter (errmsg)
-**          to [sqlite3_exec()] is not NULL, then an error message is
-**          allocated using the equivalent of [sqlite3_mprintf()] and
-**          *errmsg is made to point to that message.
-**
-** {F12134} The [sqlite3_exec()] routine does not change the value of
-**          *errmsg if errmsg is NULL or if there are no errors.
-**
-** {F12137} The [sqlite3_exec()] function sets the error code and message
-**          accessible via [sqlite3_errcode()], [sqlite3_errmsg()], and
-**          [sqlite3_errmsg16()].
-**
-** LIMITATIONS:
-**
-** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open
-**          [database connection].
-**
-** {U12142} The database connection must not be closed while
-**          [sqlite3_exec()] is running.
-** 
-** {U12143} The calling function is should use [sqlite3_free()] to free
-**          the memory that *errmsg is left pointing at once the error
-**          message is no longer needed.
-**
-** {U12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
-**          must remain unchanged while [sqlite3_exec()] is running.
+** Requirements:
+** [H12101] [H12102] [H12104] [H12105] [H12107] [H12110] [H12113] [H12116]
+** [H12119] [H12122] [H12125] [H12131] [H12134] [H12137] [H12138]
 */
-int sqlite3_exec(
+SQLITE_API int sqlite3_exec(
   sqlite3*,                                  /* An open database */
-  const char *sql,                           /* SQL to be evaluted */
+  const char *sql,                           /* SQL to be evaluated */
   int (*callback)(void*,int,char**,char**),  /* Callback function */
   void *,                                    /* 1st argument to callback */
   char **errmsg                              /* Error msg written here */
 );
 
 /*
-** CAPI3REF: Result Codes {F10210}
+** CAPI3REF: Result Codes {H10210} <S10700>
 ** KEYWORDS: SQLITE_OK {error code} {error codes}
+** KEYWORDS: {result code} {result codes}
 **
 ** Many SQLite functions return an integer result code from the set shown
 ** here in order to indicates success or failure.
 **
+** New error codes may be added in future versions of SQLite.
+**
 ** See also: [SQLITE_IOERR_READ | extended result codes]
 */
 #define SQLITE_OK           0   /* Successful result */
@@ -402,20 +376,20 @@ int sqlite3_exec(
 /* end-of-error-codes */
 
 /*
-** CAPI3REF: Extended Result Codes {F10220}
+** CAPI3REF: Extended Result Codes {H10220} <S10700>
 ** KEYWORDS: {extended error code} {extended error codes}
-** KEYWORDS: {extended result codes}
+** KEYWORDS: {extended result code} {extended result codes}
 **
 ** In its default configuration, SQLite API routines return one of 26 integer
-** [SQLITE_OK | result codes].  However, experience has shown that
-** many of these result codes are too course-grained.  They do not provide as
+** [SQLITE_OK | result codes].  However, experience has shown that many of
+** these result codes are too coarse-grained.  They do not provide as
 ** much information about problems as programmers might like.  In an effort to
 ** address this, newer versions of SQLite (version 3.3.8 and later) include
 ** support for additional result codes that provide more detailed information
 ** about errors. The extended result codes are enabled or disabled
-** for each database connection using the [sqlite3_extended_result_codes()]
-** API.
-** 
+** on a per database connection basis using the
+** [sqlite3_extended_result_codes()] API.
+**
 ** Some of the available extended result codes are listed here.
 ** One may expect the number of extended result codes will be expand
 ** over time.  Software that uses extended result codes should expect
@@ -423,56 +397,53 @@ int sqlite3_exec(
 **
 ** The SQLITE_OK result code will never be extended.  It will always
 ** be exactly zero.
-** 
-** INVARIANTS:
-**
-** {F10223} The symbolic name for an extended result code always contains
-**          a related primary result code as a prefix.
-**
-** {F10224} Primary result code names contain a single "_" character.
-**
-** {F10225} Extended result code names contain two or more "_" characters.
-**
-** {F10226} The numeric value of an extended result code contains the
-**          numeric value of its corresponding primary result code in
-**          its least significant 8 bits.
 */
-#define SQLITE_IOERR_READ          (SQLITE_IOERR | (1<<8))
-#define SQLITE_IOERR_SHORT_READ    (SQLITE_IOERR | (2<<8))
-#define SQLITE_IOERR_WRITE         (SQLITE_IOERR | (3<<8))
-#define SQLITE_IOERR_FSYNC         (SQLITE_IOERR | (4<<8))
-#define SQLITE_IOERR_DIR_FSYNC     (SQLITE_IOERR | (5<<8))
-#define SQLITE_IOERR_TRUNCATE      (SQLITE_IOERR | (6<<8))
-#define SQLITE_IOERR_FSTAT         (SQLITE_IOERR | (7<<8))
-#define SQLITE_IOERR_UNLOCK        (SQLITE_IOERR | (8<<8))
-#define SQLITE_IOERR_RDLOCK        (SQLITE_IOERR | (9<<8))
-#define SQLITE_IOERR_DELETE        (SQLITE_IOERR | (10<<8))
-#define SQLITE_IOERR_BLOCKED       (SQLITE_IOERR | (11<<8))
-#define SQLITE_IOERR_NOMEM         (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
+#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
+#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
+#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
+#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
+#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
+#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
+#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
+#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
+#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
+#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
+#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
+#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
+#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
+#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
+#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
+#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED | (1<<8) )
 
 /*
-** CAPI3REF: Flags For File Open Operations {F10230}
+** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
 **
 ** These bit values are intended for use in the
 ** 3rd parameter to the [sqlite3_open_v2()] interface and
 ** in the 4th parameter to the xOpen method of the
 ** [sqlite3_vfs] object.
 */
-#define SQLITE_OPEN_READONLY         0x00000001
-#define SQLITE_OPEN_READWRITE        0x00000002
-#define SQLITE_OPEN_CREATE           0x00000004
-#define SQLITE_OPEN_DELETEONCLOSE    0x00000008
-#define SQLITE_OPEN_EXCLUSIVE        0x00000010
-#define SQLITE_OPEN_MAIN_DB          0x00000100
-#define SQLITE_OPEN_TEMP_DB          0x00000200
-#define SQLITE_OPEN_TRANSIENT_DB     0x00000400
-#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800
-#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000
-#define SQLITE_OPEN_SUBJOURNAL       0x00002000
-#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000
+#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
+#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
+#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
+#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
+#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
+#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
+#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
+#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
+#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
+#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
 
 /*
-** CAPI3REF: Device Characteristics {F10240}
+** CAPI3REF: Device Characteristics {H10240} <H11120>
 **
 ** The xDeviceCapabilities method of the [sqlite3_io_methods]
 ** object returns an integer which is a vector of the these
@@ -504,7 +475,7 @@ int sqlite3_exec(
 #define SQLITE_IOCAP_SEQUENTIAL      0x00000400
 
 /*
-** CAPI3REF: File Locking Levels {F10250}
+** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
 **
 ** SQLite uses one of these integer values as the second
 ** argument to calls it makes to the xLock() and xUnlock() methods
@@ -517,7 +488,7 @@ int sqlite3_exec(
 #define SQLITE_LOCK_EXCLUSIVE     4
 
 /*
-** CAPI3REF: Synchronization Type Flags {F10260}
+** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
 **
 ** When SQLite invokes the xSync() method of an
 ** [sqlite3_io_methods] object it uses a combination of
@@ -525,20 +496,21 @@ int sqlite3_exec(
 **
 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
 ** sync operation only needs to flush data to mass storage.  Inode
-** information need not be flushed. The SQLITE_SYNC_NORMAL flag means 
-** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means 
-** to use Mac OS-X style fullsync instead of fsync().
+** information need not be flushed. If the lower four bits of the flag
+** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
+** If the lower four bits equal SQLITE_SYNC_FULL, that means
+** to use Mac OS X style fullsync instead of fsync().
 */
 #define SQLITE_SYNC_NORMAL        0x00002
 #define SQLITE_SYNC_FULL          0x00003
 #define SQLITE_SYNC_DATAONLY      0x00010
 
-
 /*
-** CAPI3REF: OS Interface Open File Handle {F11110}
+** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
 **
-** An [sqlite3_file] object represents an open file in the OS
-** interface layer.  Individual OS interface implementations will
+** An [sqlite3_file] object represents an open file in the 
+** [sqlite3_vfs | OS interface layer].  Individual OS interface
+** implementations will
 ** want to subclass this object by appending additional fields
 ** for their own use.  The pMethods entry is a pointer to an
 ** [sqlite3_io_methods] object that defines methods for performing
@@ -550,19 +522,26 @@ struct sqlite3_file {
 };
 
 /*
-** CAPI3REF: OS Interface File Virtual Methods Object {F11120}
+** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
 **
-** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to
-** an instance of this object.  This object defines the
-** methods used to perform various operations against the open file.
+** Every file opened by the [sqlite3_vfs] xOpen method populates an
+** [sqlite3_file] object (or, more commonly, a subclass of the
+** [sqlite3_file] object) with a pointer to an instance of this object.
+** This object defines the methods used to perform various operations
+** against the open file represented by the [sqlite3_file] object.
+**
+** If the xOpen method sets the sqlite3_file.pMethods element 
+** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
+** may be invoked even if the xOpen reported that it failed.  The
+** only way to prevent a call to xClose following a failed xOpen
+** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
 **
 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
 ** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
-*  The second choice is an
-** OS-X style fullsync.  The SQLITE_SYNC_DATA flag may be ORed in to
-** indicate that only the data of the file and not its inode needs to be
-** synced.
-** 
+** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
+** flag may be ORed in to indicate that only the data of the file
+** and not its inode needs to be synced.
+**
 ** The integer values to xLock() and xUnlock() are one of
 ** <ul>
 ** <li> [SQLITE_LOCK_NONE],
@@ -571,26 +550,24 @@ struct sqlite3_file {
 ** <li> [SQLITE_LOCK_PENDING], or
 ** <li> [SQLITE_LOCK_EXCLUSIVE].
 ** </ul>
-** xLock() increases the lock. xUnlock() decreases the lock.  
-** The xCheckReservedLock() method looks
-** to see if any database connection, either in this
-** process or in some other process, is holding an RESERVED,
+** xLock() increases the lock. xUnlock() decreases the lock.
+** The xCheckReservedLock() method checks whether any database connection,
+** either in this process or in some other process, is holding a RESERVED,
 ** PENDING, or EXCLUSIVE lock on the file.  It returns true
-** if such a lock exists and false if not.
-** 
+** if such a lock exists and false otherwise.
+**
 ** The xFileControl() method is a generic interface that allows custom
 ** VFS implementations to directly control an open file using the
-** [sqlite3_file_control()] interface.  The second "op" argument
-** is an integer opcode.   The third
-** argument is a generic pointer which is intended to be a pointer
-** to a structure that may contain arguments or space in which to
+** [sqlite3_file_control()] interface.  The second "op" argument is an
+** integer opcode.  The third argument is a generic pointer intended to
+** point to a structure that may contain arguments or space in which to
 ** write return values.  Potential uses for xFileControl() might be
 ** functions to enable blocking locks with timeouts, to change the
 ** locking strategy (for example to use dot-file locks), to inquire
 ** about the status of a lock, or to break stale locks.  The SQLite
-** core reserves opcodes less than 100 for its own use. 
+** core reserves all opcodes less than 100 for its own use.
 ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
-** Applications that define a custom xFileControl method should use opcodes 
+** Applications that define a custom xFileControl method should use opcodes
 ** greater than 100 to avoid conflicts.
 **
 ** The xSectorSize() method returns the sector size of the
@@ -624,6 +601,12 @@ struct sqlite3_file {
 ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
 ** information is written to disk in the same order as calls
 ** to xWrite().
+**
+** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
+** in the unread portions of the buffer with zeros.  A VFS that
+** fails to zero-fill short reads might seem to work.  However,
+** failure to zero-fill short reads will eventually lead to
+** database corruption.
 */
 typedef struct sqlite3_io_methods sqlite3_io_methods;
 struct sqlite3_io_methods {
@@ -636,7 +619,7 @@ struct sqlite3_io_methods {
   int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
   int (*xLock)(sqlite3_file*, int);
   int (*xUnlock)(sqlite3_file*, int);
-  int (*xCheckReservedLock)(sqlite3_file*);
+  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
   int (*xFileControl)(sqlite3_file*, int op, void *pArg);
   int (*xSectorSize)(sqlite3_file*);
   int (*xDeviceCharacteristics)(sqlite3_file*);
@@ -644,10 +627,10 @@ struct sqlite3_io_methods {
 };
 
 /*
-** CAPI3REF: Standard File Control Opcodes {F11310}
+** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
 **
 ** These integer constants are opcodes for the xFileControl method
-** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()]
+** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
 ** interface.
 **
 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
@@ -659,9 +642,12 @@ struct sqlite3_io_methods {
 ** is defined.
 */
 #define SQLITE_FCNTL_LOCKSTATE        1
+#define SQLITE_GET_LOCKPROXYFILE      2
+#define SQLITE_SET_LOCKPROXYFILE      3
+#define SQLITE_LAST_ERRNO             4
 
 /*
-** CAPI3REF: Mutex Handle {F17110}
+** CAPI3REF: Mutex Handle {H17110} <S20130>
 **
 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
 ** abstract type for a mutex object.  The SQLite core never looks
@@ -673,15 +659,18 @@ struct sqlite3_io_methods {
 typedef struct sqlite3_mutex sqlite3_mutex;
 
 /*
-** CAPI3REF: OS Interface Object {F11140}
+** CAPI3REF: OS Interface Object {H11140} <S20100>
 **
-** An instance of this object defines the interface between the
-** SQLite core and the underlying operating system.  The "vfs"
+** An instance of the sqlite3_vfs object defines the interface between
+** the SQLite core and the underlying operating system.  The "vfs"
 ** in the name of the object stands for "virtual file system".
 **
-** The iVersion field is initially 1 but may be larger for future
-** versions of SQLite.  Additional fields may be appended to this
-** object when the iVersion value is increased.
+** The value of the iVersion field is initially 1 but may be larger in
+** future versions of SQLite.  Additional fields may be appended to this
+** object when the iVersion value is increased.  Note that the structure
+** of the sqlite3_vfs object changes in the transaction between
+** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
+** modified.
 **
 ** The szOsFile field is the size of the subclassed [sqlite3_file]
 ** structure used by this VFS.  mxPathname is the maximum length of
@@ -691,9 +680,10 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** the pNext pointer.  The [sqlite3_vfs_register()]
 ** and [sqlite3_vfs_unregister()] interfaces manage this list
 ** in a thread-safe way.  The [sqlite3_vfs_find()] interface
-** searches the list.
+** searches the list.  Neither the application code nor the VFS
+** implementation should use the pNext pointer.
 **
-** The pNext field is the only field in the sqlite3_vfs 
+** The pNext field is the only field in the sqlite3_vfs
 ** structure that SQLite will ever modify.  SQLite will only access
 ** or modify this field while holding a particular static mutex.
 ** The application should never modify anything within the sqlite3_vfs
@@ -702,23 +692,28 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** The zName field holds the name of the VFS module.  The name must
 ** be unique across all VFS modules.
 **
-** {F11141} SQLite will guarantee that the zFilename string passed to
-** xOpen() is a full pathname as generated by xFullPathname() and
-** that the string will be valid and unchanged until xClose() is
-** called.  {END} So the [sqlite3_file] can store a pointer to the
+** SQLite will guarantee that the zFilename parameter to xOpen
+** is either a NULL pointer or string obtained
+** from xFullPathname().  SQLite further guarantees that
+** the string will be valid and unchanged until xClose() is
+** called. Because of the previous sentence,
+** the [sqlite3_file] can safely store a pointer to the
 ** filename if it needs to remember the filename for some reason.
+** If the zFilename parameter is xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  Whenever the 
+** xFilename parameter is NULL it will also be the case that the
+** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
 **
-** {F11142} The flags argument to xOpen() includes all bits set in
+** The flags argument to xOpen() includes all bits set in
 ** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
 ** or [sqlite3_open16()] is used, then flags includes at least
-** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END}
+** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
 ** If xOpen() opens a file read-only then it sets *pOutFlags to
-** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be
-** set.
-** 
-** {F11143} SQLite will also add one of the following flags to the xOpen()
+** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
+**
+** SQLite will also add one of the following flags to the xOpen()
 ** call, depending on the object being opened:
-** 
+**
 ** <ul>
 ** <li>  [SQLITE_OPEN_MAIN_DB]
 ** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
@@ -727,62 +722,70 @@ typedef struct sqlite3_mutex sqlite3_mutex;
 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
-** </ul> {END}
+** </ul>
 **
 ** The file I/O implementation can use the object type flags to
-** changes the way it deals with files.  For example, an application
+** change the way it deals with files.  For example, an application
 ** that does not care about crash recovery or rollback might make
 ** the open of a journal file a no-op.  Writes to this journal would
-** also be no-ops, and any attempt to read the journal would return 
-** SQLITE_IOERR.  Or the implementation might recognize that a database 
-** file will be doing page-aligned sector reads and writes in a random 
+** also be no-ops, and any attempt to read the journal would return
+** SQLITE_IOERR.  Or the implementation might recognize that a database
+** file will be doing page-aligned sector reads and writes in a random
 ** order and set up its I/O subsystem accordingly.
-** 
-** SQLite might also add one of the following flags to the xOpen
-** method:
-** 
+**
+** SQLite might also add one of the following flags to the xOpen method:
+**
 ** <ul>
 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
 ** <li> [SQLITE_OPEN_EXCLUSIVE]
 ** </ul>
-** 
-** {F11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
-** deleted when it is closed.  {F11146} The [SQLITE_OPEN_DELETEONCLOSE]
-** will be set for TEMP  databases, journals and for subjournals. 
-** {F11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
-** for exclusive access.  This flag is set for all files except
-** for the main database file. {END}
-** 
-** {F11148} At least szOsFile bytes of memory are allocated by SQLite 
-** to hold the  [sqlite3_file] structure passed as the third 
-** argument to xOpen.  {END}  The xOpen method does not have to
-** allocate the structure; it should just fill it in.
-** 
-** {F11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 
-** to test for the existance of a file,
-** or [SQLITE_ACCESS_READWRITE] to test to see
-** if a file is readable and writable, or [SQLITE_ACCESS_READ]
-** to test to see if a file is at least readable.  {END} The file can be a 
+**
+** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
+** deleted when it is closed.  The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP  databases, journals and for subjournals.
+**
+** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** with the [SQLITE_OPEN_CREATE] flag, which are both directly
+** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
+** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
+** SQLITE_OPEN_CREATE, is used to indicate that file should always
+** be created, and that it is an error if it already exists.
+** It is <i>not</i> used to indicate the file should be opened 
+** for exclusive access.
+**
+** At least szOsFile bytes of memory are allocated by SQLite
+** to hold the  [sqlite3_file] structure passed as the third
+** argument to xOpen.  The xOpen method does not have to
+** allocate the structure; it should just fill it in.  Note that
+** the xOpen method must set the sqlite3_file.pMethods to either
+** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
+** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
+** element will be valid after xOpen returns regardless of the success
+** or failure of the xOpen call.
+**
+** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
+** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
+** to test whether a file is at least readable.   The file can be a
 ** directory.
-** 
-** {F11150} SQLite will always allocate at least mxPathname+1 bytes for
-** the output buffers for xGetTempname and xFullPathname. {F11151} The exact
-** size of the output buffer is also passed as a parameter to both 
-** methods. {END} If the output buffer is not large enough, SQLITE_CANTOPEN
-** should be returned. As this is handled as a fatal error by SQLite,
-** vfs implementations should endeavor to prevent this by setting 
-** mxPathname to a sufficiently large value.
-** 
+**
+** SQLite will always allocate at least mxPathname+1 bytes for the
+** output buffer xFullPathname.  The exact size of the output buffer
+** is also passed as a parameter to both  methods. If the output buffer
+** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
+** handled as a fatal error by SQLite, vfs implementations should endeavor
+** to prevent this by setting mxPathname to a sufficiently large value.
+**
 ** The xRandomness(), xSleep(), and xCurrentTime() interfaces
 ** are not strictly a part of the filesystem, but they are
 ** included in the VFS structure for completeness.
 ** The xRandomness() function attempts to return nBytes bytes
 ** of good-quality randomness into zOut.  The return value is
-** the actual number of bytes of randomness obtained.  The
-** xSleep() method causes the calling thread to sleep for at
+** the actual number of bytes of randomness obtained.
+** The xSleep() method causes the calling thread to sleep for at
 ** least the number of microseconds given.  The xCurrentTime()
-** method returns a Julian Day Number for the current date and
-** time.
+** method returns a Julian Day Number for the current date and time.
+**
 */
 typedef struct sqlite3_vfs sqlite3_vfs;
 struct sqlite3_vfs {
@@ -795,134 +798,540 @@ struct sqlite3_vfs {
   int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
                int flags, int *pOutFlags);
   int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
-  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
-  int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut);
+  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
   int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
   void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
   void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
-  void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
+  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
   void (*xDlClose)(sqlite3_vfs*, void*);
   int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
   int (*xSleep)(sqlite3_vfs*, int microseconds);
   int (*xCurrentTime)(sqlite3_vfs*, double*);
+  int (*xGetLastError)(sqlite3_vfs*, int, char *);
   /* New fields may be appended in figure versions.  The iVersion
   ** value will increment whenever this happens. */
 };
 
 /*
-** CAPI3REF: Flags for the xAccess VFS method {F11190}
+** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
 **
-** {F11191} These integer constants can be used as the third parameter to
+** These integer constants can be used as the third parameter to
 ** the xAccess method of an [sqlite3_vfs] object. {END}  They determine
-** what kind of permissions the xAccess method is
-** looking for.  {F11192} With SQLITE_ACCESS_EXISTS, the xAccess method
-** simply checks to see if the file exists. {F11193} With
-** SQLITE_ACCESS_READWRITE, the xAccess method checks to see
-** if the file is both readable and writable.  {F11194} With
-** SQLITE_ACCESS_READ the xAccess method
-** checks to see if the file is readable.
+** what kind of permissions the xAccess method is looking for.
+** With SQLITE_ACCESS_EXISTS, the xAccess method
+** simply checks whether the file exists.
+** With SQLITE_ACCESS_READWRITE, the xAccess method
+** checks whether the file is both readable and writable.
+** With SQLITE_ACCESS_READ, the xAccess method
+** checks whether the file is readable.
 */
 #define SQLITE_ACCESS_EXISTS    0
 #define SQLITE_ACCESS_READWRITE 1
 #define SQLITE_ACCESS_READ      2
 
 /*
-** CAPI3REF: Enable Or Disable Extended Result Codes {F12200}
+** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
+**
+** The sqlite3_initialize() routine initializes the
+** SQLite library.  The sqlite3_shutdown() routine
+** deallocates any resources that were allocated by sqlite3_initialize().
+**
+** A call to sqlite3_initialize() is an "effective" call if it is
+** the first time sqlite3_initialize() is invoked during the lifetime of
+** the process, or if it is the first time sqlite3_initialize() is invoked
+** following a call to sqlite3_shutdown().  Only an effective call
+** of sqlite3_initialize() does any initialization.  All other calls
+** are harmless no-ops.
+**
+** A call to sqlite3_shutdown() is an "effective" call if it is the first
+** call to sqlite3_shutdown() since the last sqlite3_initialize().  Only
+** an effective call to sqlite3_shutdown() does any deinitialization.
+** All other calls to sqlite3_shutdown() are harmless no-ops.
+**
+** Among other things, sqlite3_initialize() shall invoke
+** sqlite3_os_init().  Similarly, sqlite3_shutdown()
+** shall invoke sqlite3_os_end().
+**
+** The sqlite3_initialize() routine returns [SQLITE_OK] on success.
+** If for some reason, sqlite3_initialize() is unable to initialize
+** the library (perhaps it is unable to allocate a needed resource such
+** as a mutex) it returns an [error code] other than [SQLITE_OK].
+**
+** The sqlite3_initialize() routine is called internally by many other
+** SQLite interfaces so that an application usually does not need to
+** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
+** calls sqlite3_initialize() so the SQLite library will be automatically
+** initialized when [sqlite3_open()] is called if it has not be initialized
+** already.  However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
+** compile-time option, then the automatic calls to sqlite3_initialize()
+** are omitted and the application must call sqlite3_initialize() directly
+** prior to using any other SQLite interface.  For maximum portability,
+** it is recommended that applications always invoke sqlite3_initialize()
+** directly prior to using any other SQLite interface.  Future releases
+** of SQLite may require this.  In other words, the behavior exhibited
+** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
+** default behavior in some future release of SQLite.
+**
+** The sqlite3_os_init() routine does operating-system specific
+** initialization of the SQLite library.  The sqlite3_os_end()
+** routine undoes the effect of sqlite3_os_init().  Typical tasks
+** performed by these routines include allocation or deallocation
+** of static resources, initialization of global variables,
+** setting up a default [sqlite3_vfs] module, or setting up
+** a default configuration using [sqlite3_config()].
+**
+** The application should never invoke either sqlite3_os_init()
+** or sqlite3_os_end() directly.  The application should only invoke
+** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
+** interface is called automatically by sqlite3_initialize() and
+** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
+** implementations for sqlite3_os_init() and sqlite3_os_end()
+** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
+** When [custom builds | built for other platforms]
+** (using the [SQLITE_OS_OTHER=1] compile-time
+** option) the application must supply a suitable implementation for
+** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
+** implementation of sqlite3_os_init() or sqlite3_os_end()
+** must return [SQLITE_OK] on success and some other [error code] upon
+** failure.
+*/
+SQLITE_API int sqlite3_initialize(void);
+SQLITE_API int sqlite3_shutdown(void);
+SQLITE_API int sqlite3_os_init(void);
+SQLITE_API int sqlite3_os_end(void);
+
+/*
+** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
+** EXPERIMENTAL
+**
+** The sqlite3_config() interface is used to make global configuration
+** changes to SQLite in order to tune SQLite to the specific needs of
+** the application.  The default configuration is recommended for most
+** applications and so this routine is usually not necessary.  It is
+** provided to support rare applications with unusual needs.
+**
+** The sqlite3_config() interface is not threadsafe.  The application
+** must insure that no other SQLite interfaces are invoked by other
+** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** Note, however, that sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
+** The first argument to sqlite3_config() is an integer
+** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
+** what property of SQLite is to be configured.  Subsequent arguments
+** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
+** in the first argument.
+**
+** When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
+** If the option is unknown or SQLite is unable to set the option
+** then this routine returns a non-zero [error code].
+**
+** Requirements:
+** [H14103] [H14106] [H14120] [H14123] [H14126] [H14129] [H14132] [H14135]
+** [H14138] [H14141] [H14144] [H14147] [H14150] [H14153] [H14156] [H14159]
+** [H14162] [H14165] [H14168]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);
+
+/*
+** CAPI3REF: Configure database connections  {H14200} <S20000>
+** EXPERIMENTAL
+**
+** The sqlite3_db_config() interface is used to make configuration
+** changes to a [database connection].  The interface is similar to
+** [sqlite3_config()] except that the changes apply to a single
+** [database connection] (specified in the first argument).  The
+** sqlite3_db_config() interface can only be used immediately after
+** the database connection is created using [sqlite3_open()],
+** [sqlite3_open16()], or [sqlite3_open_v2()].  
+**
+** The second argument to sqlite3_db_config(D,V,...)  is the
+** configuration verb - an integer code that indicates what
+** aspect of the [database connection] is being configured.
+** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
+** New verbs are likely to be added in future releases of SQLite.
+** Additional arguments depend on the verb.
+**
+** Requirements:
+** [H14203] [H14206] [H14209] [H14212] [H14215]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
+** EXPERIMENTAL
+**
+** An instance of this object defines the interface between SQLite
+** and low-level memory allocation routines.
+**
+** This object is used in only one place in the SQLite interface.
+** A pointer to an instance of this object is the argument to
+** [sqlite3_config()] when the configuration option is
+** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
+** By creating an instance of this object
+** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
+** during configuration, an application can specify an alternative
+** memory allocation subsystem for SQLite to use for all of its
+** dynamic memory needs.
+**
+** Note that SQLite comes with several [built-in memory allocators]
+** that are perfectly adequate for the overwhelming majority of applications
+** and that this object is only useful to a tiny minority of applications
+** with specialized memory allocation requirements.  This object is
+** also used during testing of SQLite in order to specify an alternative
+** memory allocator that simulates memory out-of-memory conditions in
+** order to verify that SQLite recovers gracefully from such
+** conditions.
+**
+** The xMalloc and xFree methods must work like the
+** malloc() and free() functions from the standard C library.
+** The xRealloc method must work like realloc() from the standard C library
+** with the exception that if the second argument to xRealloc is zero,
+** xRealloc must be a no-op - it must not perform any allocation or
+** deallocation.  SQLite guaranteeds that the second argument to
+** xRealloc is always a value returned by a prior call to xRoundup.
+** And so in cases where xRoundup always returns a positive number,
+** xRealloc can perform exactly as the standard library realloc() and
+** still be in compliance with this specification.
+**
+** xSize should return the allocated size of a memory allocation
+** previously obtained from xMalloc or xRealloc.  The allocated size
+** is always at least as big as the requested size but may be larger.
+**
+** The xRoundup method returns what would be the allocated size of
+** a memory allocation given a particular requested size.  Most memory
+** allocators round up memory allocations at least to the next multiple
+** of 8.  Some allocators round up to a larger multiple or to a power of 2.
+** Every memory allocation request coming in through [sqlite3_malloc()]
+** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
+** that causes the corresponding memory allocation to fail.
+**
+** The xInit method initializes the memory allocator.  (For example,
+** it might allocate any require mutexes or initialize internal data
+** structures.  The xShutdown method is invoked (indirectly) by
+** [sqlite3_shutdown()] and should deallocate any resources acquired
+** by xInit.  The pAppData pointer is used as the only parameter to
+** xInit and xShutdown.
+**
+** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe.  The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  For all other methods, SQLite
+** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
+** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
+** it is by default) and so the methods are automatically serialized.
+** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
+** methods must be threadsafe or else make their own arrangements for
+** serialization.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+*/
+typedef struct sqlite3_mem_methods sqlite3_mem_methods;
+struct sqlite3_mem_methods {
+  void *(*xMalloc)(int);         /* Memory allocation function */
+  void (*xFree)(void*);          /* Free a prior allocation */
+  void *(*xRealloc)(void*,int);  /* Resize an allocation */
+  int (*xSize)(void*);           /* Return the size of an allocation */
+  int (*xRoundup)(int);          /* Round up request size to allocation size */
+  int (*xInit)(void*);           /* Initialize the memory allocator */
+  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
+  void *pAppData;                /* Argument to xInit() and xShutdown() */
+};
+
+/*
+** CAPI3REF: Configuration Options {H10160} <S20000>
+** EXPERIMENTAL
 **
-** The sqlite3_extended_result_codes() routine enables or disables the
-** [SQLITE_IOERR_READ | extended result codes] feature of SQLite.
-** The extended result codes are disabled by default for historical
-** compatibility.
+** These constants are the available integer configuration options that
+** can be passed as the first argument to the [sqlite3_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_config()] to make sure that
+** the call worked.  The [sqlite3_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
+** <dd>There are no arguments to this option.  This option disables
+** all mutexing and puts SQLite into a mode where it can only be used
+** by a single thread.</dd>
+**
+** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
+** <dd>There are no arguments to this option.  This option disables
+** mutexing on [database connection] and [prepared statement] objects.
+** The application is responsible for serializing access to
+** [database connections] and [prepared statements].  But other mutexes
+** are enabled so that SQLite will be safe to use in a multi-threaded
+** environment as long as no two threads attempt to use the same
+** [database connection] at the same time.  See the [threading mode]
+** documentation for additional information.</dd>
+**
+** <dt>SQLITE_CONFIG_SERIALIZED</dt>
+** <dd>There are no arguments to this option.  This option enables
+** all mutexes including the recursive
+** mutexes on [database connection] and [prepared statement] objects.
+** In this mode (which is the default when SQLite is compiled with
+** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
+** to [database connections] and [prepared statements] so that the
+** application is free to use the same [database connection] or the
+** same [prepared statement] in different threads at the same time.
+** See the [threading mode] documentation for additional information.</dd>
+**
+** <dt>SQLITE_CONFIG_MALLOC</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The argument specifies
+** alternative low-level memory allocation routines to be used in place of
+** the memory allocation routines built into SQLite.</dd>
+**
+** <dt>SQLITE_CONFIG_GETMALLOC</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
+** structure is filled with the currently defined memory allocation routines.
+** This option can be used to overload the default memory allocation
+** routines with a wrapper that simulations memory allocation failure or
+** tracks memory usage, for example.</dd>
+**
+** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
+** <dd>This option takes single argument of type int, interpreted as a 
+** boolean, which enables or disables the collection of memory allocation 
+** statistics. When disabled, the following SQLite interfaces become 
+** non-operational:
+**   <ul>
+**   <li> [sqlite3_memory_used()]
+**   <li> [sqlite3_memory_highwater()]
+**   <li> [sqlite3_soft_heap_limit()]
+**   <li> [sqlite3_status()]
+**   </ul>
+** </dd>
+**
+** <dt>SQLITE_CONFIG_SCRATCH</dt>
+** <dd>This option specifies a static memory buffer that SQLite can use for
+** scratch memory.  There are three arguments:  A pointer an 8-byte
+** aligned memory buffer from which the scrach allocations will be
+** drawn, the size of each scratch allocation (sz),
+** and the maximum number of scratch allocations (N).  The sz
+** argument must be a multiple of 16. The sz parameter should be a few bytes
+** larger than the actual scratch space required due to internal overhead.
+** The first argument should pointer to an 8-byte aligned buffer
+** of at least sz*N bytes of memory.
+** SQLite will use no more than one scratch buffer at once per thread, so
+** N should be set to the expected maximum number of threads.  The sz
+** parameter should be 6 times the size of the largest database page size.
+** Scratch buffers are used as part of the btree balance operation.  If
+** The btree balancer needs additional memory beyond what is provided by
+** scratch buffers or if no scratch buffer space is specified, then SQLite
+** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
+**
+** <dt>SQLITE_CONFIG_PAGECACHE</dt>
+** <dd>This option specifies a static memory buffer that SQLite can use for
+** the database page cache with the default page cache implemenation.  
+** This configuration should not be used if an application-define page
+** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
+** There are three arguments to this option: A pointer to 8-byte aligned
+** memory, the size of each page buffer (sz), and the number of pages (N).
+** The sz argument should be the size of the largest database page
+** (a power of two between 512 and 32768) plus a little extra for each
+** page header.  The page header size is 20 to 40 bytes depending on
+** the host architecture.  It is harmless, apart from the wasted memory,
+** to make sz a little too large.  The first
+** argument should point to an allocation of at least sz*N bytes of memory.
+** SQLite will use the memory provided by the first argument to satisfy its
+** memory needs for the first N pages that it adds to cache.  If additional
+** page cache memory is needed beyond what is provided by this option, then
+** SQLite goes to [sqlite3_malloc()] for the additional storage space.
+** The implementation might use one or more of the N buffers to hold 
+** memory accounting information. The pointer in the first argument must
+** be aligned to an 8-byte boundary or subsequent behavior of SQLite
+** will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_HEAP</dt>
+** <dd>This option specifies a static memory buffer that SQLite will use
+** for all of its dynamic memory allocation needs beyond those provided
+** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
+** There are three arguments: An 8-byte aligned pointer to the memory,
+** the number of bytes in the memory buffer, and the minimum allocation size.
+** If the first pointer (the memory pointer) is NULL, then SQLite reverts
+** to using its default memory allocator (the system malloc() implementation),
+** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  If the
+** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
+** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
+** allocator is engaged to handle all of SQLites memory allocation needs.
+** The first pointer (the memory pointer) must be aligned to an 8-byte
+** boundary or subsequent behavior of SQLite will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_MUTEX</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
+** alternative low-level mutex routines to be used in place
+** the mutex routines built into SQLite.</dd>
+**
+** <dt>SQLITE_CONFIG_GETMUTEX</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The
+** [sqlite3_mutex_methods]
+** structure is filled with the currently defined mutex routines.
+** This option can be used to overload the default mutex allocation
+** routines with a wrapper used to track mutex usage for performance
+** profiling or testing, for example.</dd>
+**
+** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
+** <dd>This option takes two arguments that determine the default
+** memory allocation lookaside optimization.  The first argument is the
+** size of each lookaside buffer slot and the second is the number of
+** slots allocated to each database connection.  This option sets the
+** <i>default</i> lookaside size.  The [SQLITE_DBCONFIG_LOOKASIDE]
+** verb to [sqlite3_db_config()] can be used to change the lookaside
+** configuration on individual connections.</dd>
+**
+** <dt>SQLITE_CONFIG_PCACHE</dt>
+** <dd>This option takes a single argument which is a pointer to
+** an [sqlite3_pcache_methods] object.  This object specifies the interface
+** to a custom page cache implementation.  SQLite makes a copy of the
+** object and uses it for page cache memory allocations.</dd>
+**
+** <dt>SQLITE_CONFIG_GETPCACHE</dt>
+** <dd>This option takes a single argument which is a pointer to an
+** [sqlite3_pcache_methods] object.  SQLite copies of the current
+** page cache implementation into that object.</dd>
 **
-** INVARIANTS:
+** </dl>
+*/
+#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
+#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
+#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
+#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
+#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
+#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
+#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
+#define SQLITE_CONFIG_PCACHE       14  /* sqlite3_pcache_methods* */
+#define SQLITE_CONFIG_GETPCACHE    15  /* sqlite3_pcache_methods* */
+
+/*
+** CAPI3REF: Configuration Options {H10170} <S20000>
+** EXPERIMENTAL
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked.  The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
+** <dd>This option takes three additional arguments that determine the 
+** [lookaside memory allocator] configuration for the [database connection].
+** The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to an memory buffer to use for lookaside memory.
+** The first argument may be NULL in which case SQLite will allocate the
+** lookaside buffer itself using [sqlite3_malloc()].  The second argument is the
+** size of each lookaside buffer slot and the third argument is the number of
+** slots.  The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments.  The buffer
+** must be aligned to an 8-byte boundary.  If the second argument is not
+** a multiple of 8, it is internally rounded down to the next smaller
+** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
 **
-** {F12201} Each new [database connection] has the 
-**          [extended result codes] feature
-**          disabled by default.
+** </dl>
+*/
+#define SQLITE_DBCONFIG_LOOKASIDE    1001  /* void* int int */
+
+
+/*
+** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
+**
+** The sqlite3_extended_result_codes() routine enables or disables the
+** [extended result codes] feature of SQLite. The extended result
+** codes are disabled by default for historical compatibility considerations.
 **
-** {F12202} The [sqlite3_extended_result_codes(D,F)] interface will enable
-**          [extended result codes] for the 
-**          [database connection] D if the F parameter
-**          is true, or disable them if F is false.
+** Requirements:
+** [H12201] [H12202]
 */
-int sqlite3_extended_result_codes(sqlite3*, int onoff);
+SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
 
 /*
-** CAPI3REF: Last Insert Rowid {F12220}
+** CAPI3REF: Last Insert Rowid {H12220} <S10700>
 **
 ** Each entry in an SQLite table has a unique 64-bit signed
-** integer key called the "rowid". The rowid is always available
+** integer key called the [ROWID | "rowid"]. The rowid is always available
 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
 ** names are not also used by explicitly declared columns. If
-** the table has a column of type INTEGER PRIMARY KEY then that column
+** the table has a column of type [INTEGER PRIMARY KEY] then that column
 ** is another alias for the rowid.
 **
-** This routine returns the rowid of the most recent
-** successful INSERT into the database from the database connection
-** shown in the first argument.  If no successful inserts
-** have ever occurred on this database connection, zero is returned.
+** This routine returns the [rowid] of the most recent
+** successful [INSERT] into the database from the [database connection]
+** in the first argument.  If no successful [INSERT]s
+** have ever occurred on that database connection, zero is returned.
 **
-** If an INSERT occurs within a trigger, then the rowid of the
-** inserted row is returned by this routine as long as the trigger
-** is running.  But once the trigger terminates, the value returned
-** by this routine reverts to the last value inserted before the
-** trigger fired.
+** If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
+** row is returned by this routine as long as the trigger is running.
+** But once the trigger terminates, the value returned by this routine
+** reverts to the last value inserted before the trigger fired.
 **
-** An INSERT that fails due to a constraint violation is not a
-** successful insert and does not change the value returned by this
+** An [INSERT] that fails due to a constraint violation is not a
+** successful [INSERT] and does not change the value returned by this
 ** routine.  Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
 ** and INSERT OR ABORT make no changes to the return value of this
-** routine when their insertion fails.  When INSERT OR REPLACE 
+** routine when their insertion fails.  When INSERT OR REPLACE
 ** encounters a constraint violation, it does not fail.  The
 ** INSERT continues to completion after deleting rows that caused
 ** the constraint problem so INSERT OR REPLACE will always change
-** the return value of this interface. 
+** the return value of this interface.
 **
-** For the purposes of this routine, an insert is considered to
+** For the purposes of this routine, an [INSERT] is considered to
 ** be successful even if it is subsequently rolled back.
 **
-** INVARIANTS:
-**
-** {F12221} The [sqlite3_last_insert_rowid()] function returns the
-**          rowid of the most recent successful insert done
-**          on the same database connection and within the same
-**          trigger context, or zero if there have
-**          been no qualifying inserts on that connection.
+** Requirements:
+** [H12221] [H12223]
 **
-** {F12223} The [sqlite3_last_insert_rowid()] function returns
-**          same value when called from the same trigger context
-**          immediately before and after a ROLLBACK.
-**
-** LIMITATIONS:
-**
-** {U12232} If a separate thread does a new insert on the same
-**          database connection while the [sqlite3_last_insert_rowid()]
-**          function is running and thus changes the last insert rowid,
-**          then the value returned by [sqlite3_last_insert_rowid()] is
-**          unpredictable and might not equal either the old or the new
-**          last insert rowid.
+** If a separate thread performs a new [INSERT] on the same
+** database connection while the [sqlite3_last_insert_rowid()]
+** function is running and thus changes the last insert [rowid],
+** then the value returned by [sqlite3_last_insert_rowid()] is
+** unpredictable and might not equal either the old or the new
+** last insert [rowid].
 */
-sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
+SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
 
 /*
-** CAPI3REF: Count The Number Of Rows Modified {F12240}
+** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
 **
 ** This function returns the number of database rows that were changed
 ** or inserted or deleted by the most recently completed SQL statement
-** on the connection specified by the first parameter.  Only
-** changes that are directly specified by the INSERT, UPDATE, or
-** DELETE statement are counted.  Auxiliary changes caused by
-** triggers are not counted. Use the [sqlite3_total_changes()] function
-** to find the total number of changes including changes caused by triggers.
+** on the [database connection] specified by the first parameter.
+** Only changes that are directly specified by the [INSERT], [UPDATE],
+** or [DELETE] statement are counted.  Auxiliary changes caused by
+** triggers or [foreign key actions] are not counted. Use the
+** [sqlite3_total_changes()] function to find the total number of changes
+** including changes caused by triggers and foreign key actions.
+**
+** Changes to a view that are simulated by an [INSTEAD OF trigger]
+** are not counted.  Only real table changes are counted.
 **
 ** A "row change" is a change to a single row of a single table
 ** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
-** are changed as side effects of REPLACE constraint resolution,
-** rollback, ABORT processing, DROP TABLE, or by any other
+** are changed as side effects of [REPLACE] constraint resolution,
+** rollback, ABORT processing, [DROP TABLE], or by any other
 ** mechanisms do not count as direct row changes.
 **
 ** A "trigger context" is a scope of execution that begins and
-** ends with the script of a trigger.  Most SQL statements are
+** ends with the script of a [CREATE TRIGGER | trigger]. 
+** Most SQL statements are
 ** evaluated outside of any trigger.  This is the "top level"
 ** trigger context.  If a trigger fires from the top level, a
 ** new trigger context is entered for the duration of that one
@@ -935,84 +1344,57 @@ sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
 ** most recent INSERT, UPDATE, or DELETE statement within the same
 ** trigger context.
 **
-** So when called from the top level, this function returns the
+** Thus, when called from the top level, this function returns the
 ** number of changes in the most recent INSERT, UPDATE, or DELETE
-** that also occurred at the top level.
-** Within the body of a trigger, the sqlite3_changes() interface
-** can be called to find the number of
+** that also occurred at the top level.  Within the body of a trigger,
+** the sqlite3_changes() interface can be called to find the number of
 ** changes in the most recently completed INSERT, UPDATE, or DELETE
 ** statement within the body of the same trigger.
-** However, the number returned does not include in changes
-** caused by subtriggers since they have their own context.
-**
-** SQLite implements the command "DELETE FROM table" without
-** a WHERE clause by dropping and recreating the table.  (This is much
-** faster than going through and deleting individual elements from the
-** table.)  Because of this optimization, the deletions in
-** "DELETE FROM table" are not row changes and will not be counted
-** by the sqlite3_changes() or [sqlite3_total_changes()] functions.
-** To get an accurate count of the number of rows deleted, use
-** "DELETE FROM table WHERE 1" instead.
-**
-** INVARIANTS:
-**
-** {F12241} The [sqlite3_changes()] function returns the number of
-**          row changes caused by the most recent INSERT, UPDATE,
-**          or DELETE statement on the same database connection and
-**          within the same trigger context, or zero if there have
-**          not been any qualifying row changes.
-**
-** LIMITATIONS:
-**
-** {U12252} If a separate thread makes changes on the same database connection
-**          while [sqlite3_changes()] is running then the value returned
-**          is unpredictable and unmeaningful.
-*/
-int sqlite3_changes(sqlite3*);
-
-/*
-** CAPI3REF: Total Number Of Rows Modified {F12260}
-***
-** This function returns the number of row changes caused
-** by INSERT, UPDATE or DELETE statements since the database handle
-** was opened.  The count includes all changes from all trigger
-** contexts.  But the count does not include changes used to
-** implement REPLACE constraints, do rollbacks or ABORT processing,
-** or DROP table processing.
-** The changes
-** are counted as soon as the statement that makes them is completed 
-** (when the statement handle is passed to [sqlite3_reset()] or 
-** [sqlite3_finalize()]).
+** However, the number returned does not include changes
+** caused by subtriggers since those have their own context.
 **
-** SQLite implements the command "DELETE FROM table" without
-** a WHERE clause by dropping and recreating the table.  (This is much
-** faster than going
-** through and deleting individual elements from the table.)  Because of
-** this optimization, the change count for "DELETE FROM table" will be
-** zero regardless of the number of elements that were originally in the
-** table. To get an accurate count of the number of rows deleted, use
-** "DELETE FROM table WHERE 1" instead.
+** See also the [sqlite3_total_changes()] interface and the
+** [count_changes pragma].
 **
-** See also the [sqlite3_changes()] interface.
+** Requirements:
+** [H12241] [H12243]
 **
-** INVARIANTS:
-** 
-** {F12261} The [sqlite3_total_changes()] returns the total number
-**          of row changes caused by INSERT, UPDATE, and/or DELETE
-**          statements on the same [database connection], in any
-**          trigger context, since the database connection was
-**          created.
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_changes()] is running then the value returned
+** is unpredictable and not meaningful.
+*/
+SQLITE_API int sqlite3_changes(sqlite3*);
+
+/*
+** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
+**
+** This function returns the number of row changes caused by [INSERT],
+** [UPDATE] or [DELETE] statements since the [database connection] was opened.
+** The count includes all changes from all [CREATE TRIGGER | trigger] 
+** contexts and changes made by [foreign key actions]. However,
+** the count does not include changes used to implement [REPLACE] constraints,
+** do rollbacks or ABORT processing, or [DROP TABLE] processing.  The
+** count does not include rows of views that fire an [INSTEAD OF trigger],
+** though if the INSTEAD OF trigger makes changes of its own, those changes 
+** are counted.
+** The changes are counted as soon as the statement that makes them is
+** completed (when the statement handle is passed to [sqlite3_reset()] or
+** [sqlite3_finalize()]).
+**
+** See also the [sqlite3_changes()] interface and the
+** [count_changes pragma].
 **
-** LIMITATIONS:
+** Requirements:
+** [H12261] [H12263]
 **
-** {U12264} If a separate thread makes changes on the same database connection
-**          while [sqlite3_total_changes()] is running then the value 
-**          returned is unpredictable and unmeaningful.
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_total_changes()] is running then the value
+** returned is unpredictable and not meaningful.
 */
-int sqlite3_total_changes(sqlite3*);
+SQLITE_API int sqlite3_total_changes(sqlite3*);
 
 /*
-** CAPI3REF: Interrupt A Long-Running Query {F12270}
+** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
 **
 ** This function causes any pending database operation to abort and
 ** return at its earliest opportunity. This routine is typically
@@ -1022,98 +1404,99 @@ int sqlite3_total_changes(sqlite3*);
 **
 ** It is safe to call this routine from a thread different from the
 ** thread that is currently running the database operation.  But it
-** is not safe to call this routine with a database connection that
+** is not safe to call this routine with a [database connection] that
 ** is closed or might close before sqlite3_interrupt() returns.
 **
-** If an SQL is very nearly finished at the time when sqlite3_interrupt()
-** is called, then it might not have an opportunity to be interrupted.
-** It might continue to completion.
-** An SQL operation that is interrupted will return
-** [SQLITE_INTERRUPT].  If the interrupted SQL operation is an
-** INSERT, UPDATE, or DELETE that is inside an explicit transaction, 
-** then the entire transaction will be rolled back automatically.
-** A call to sqlite3_interrupt() has no effect on SQL statements
-** that are started after sqlite3_interrupt() returns.
-**
-** INVARIANTS:
-**
-** {F12271} The [sqlite3_interrupt()] interface will force all running
-**          SQL statements associated with the same database connection
-**          to halt after processing at most one additional row of
-**          data.
-**
-** {F12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
-**          will return [SQLITE_INTERRUPT].
-**
-** LIMITATIONS:
-**
-** {U12279} If the database connection closes while [sqlite3_interrupt()]
-**          is running then bad things will likely happen.
+** If an SQL operation is very nearly finished at the time when
+** sqlite3_interrupt() is called, then it might not have an opportunity
+** to be interrupted and might continue to completion.
+**
+** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
+** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
+** that is inside an explicit transaction, then the entire transaction
+** will be rolled back automatically.
+**
+** The sqlite3_interrupt(D) call is in effect until all currently running
+** SQL statements on [database connection] D complete.  Any new SQL statements
+** that are started after the sqlite3_interrupt() call and before the 
+** running statements reaches zero are interrupted as if they had been
+** running prior to the sqlite3_interrupt() call.  New SQL statements
+** that are started after the running statement count reaches zero are
+** not effected by the sqlite3_interrupt().
+** A call to sqlite3_interrupt(D) that occurs when there are no running
+** SQL statements is a no-op and has no effect on SQL statements
+** that are started after the sqlite3_interrupt() call returns.
+**
+** Requirements:
+** [H12271] [H12272]
+**
+** If the database connection closes while [sqlite3_interrupt()]
+** is running then bad things will likely happen.
 */
-void sqlite3_interrupt(sqlite3*);
+SQLITE_API void sqlite3_interrupt(sqlite3*);
 
 /*
-** CAPI3REF: Determine If An SQL Statement Is Complete {F10510}
+** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
 **
-** These routines are useful for command-line input to determine if the
-** currently entered text seems to form complete a SQL statement or
+** These routines are useful during command-line input to determine if the
+** currently entered text seems to form a complete SQL statement or
 ** if additional input is needed before sending the text into
-** SQLite for parsing.  These routines return true if the input string
+** SQLite for parsing.  These routines return 1 if the input string
 ** appears to be a complete SQL statement.  A statement is judged to be
-** complete if it ends with a semicolon token and is not a fragment of a
-** CREATE TRIGGER statement.  Semicolons that are embedded within
+** complete if it ends with a semicolon token and is not a prefix of a
+** well-formed CREATE TRIGGER statement.  Semicolons that are embedded within
 ** string literals or quoted identifier names or comments are not
 ** independent tokens (they are part of the token in which they are
-** embedded) and thus do not count as a statement terminator.
+** embedded) and thus do not count as a statement terminator.  Whitespace
+** and comments that follow the final semicolon are ignored.
 **
-** These routines do not parse the SQL and
-** so will not detect syntactically incorrect SQL.
+** These routines return 0 if the statement is incomplete.  If a
+** memory allocation fails, then SQLITE_NOMEM is returned.
 **
-** INVARIANTS:
+** These routines do not parse the SQL statements thus
+** will not detect syntactically incorrect SQL.
 **
-** {F10511} The sqlite3_complete() and sqlite3_complete16() functions
-**          return true (non-zero) if and only if the last
-**          non-whitespace token in their input is a semicolon that
-**          is not in between the BEGIN and END of a CREATE TRIGGER
-**          statement.
+** If SQLite has not been initialized using [sqlite3_initialize()] prior 
+** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
+** automatically by sqlite3_complete16().  If that initialization fails,
+** then the return value from sqlite3_complete16() will be non-zero
+** regardless of whether or not the input SQL is complete.
 **
-** LIMITATIONS:
+** Requirements: [H10511] [H10512]
 **
-** {U10512} The input to sqlite3_complete() must be a zero-terminated
-**          UTF-8 string.
+** The input to [sqlite3_complete()] must be a zero-terminated
+** UTF-8 string.
 **
-** {U10513} The input to sqlite3_complete16() must be a zero-terminated
-**          UTF-16 string in native byte order.
+** The input to [sqlite3_complete16()] must be a zero-terminated
+** UTF-16 string in native byte order.
 */
-int sqlite3_complete(const char *sql);
-int sqlite3_complete16(const void *sql);
+SQLITE_API int sqlite3_complete(const char *sql);
+SQLITE_API int sqlite3_complete16(const void *sql);
 
 /*
-** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {F12310}
+** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
+**
+** This routine sets a callback function that might be invoked whenever
+** an attempt is made to open a database table that another thread
+** or process has locked.
 **
-** This routine identifies a callback function that might be
-** invoked whenever an attempt is made to open a database table 
-** that another thread or process has locked.
-** If the busy callback is NULL, then [SQLITE_BUSY]
-** or [SQLITE_IOERR_BLOCKED]
-** is returned immediately upon encountering the lock.
-** If the busy callback is not NULL, then the
-** callback will be invoked with two arguments.  The
-** first argument to the handler is a copy of the void* pointer which
-** is the third argument to this routine.  The second argument to
-** the handler is the number of times that the busy handler has
-** been invoked for this locking event.   If the
+** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
+** is returned immediately upon encountering the lock. If the busy callback
+** is not NULL, then the callback will be invoked with two arguments.
+**
+** The first argument to the handler is a copy of the void* pointer which
+** is the third argument to sqlite3_busy_handler().  The second argument to
+** the handler callback is the number of times that the busy handler has
+** been invoked for this locking event.  If the
 ** busy callback returns 0, then no additional attempts are made to
 ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
 ** If the callback returns non-zero, then another attempt
 ** is made to open the database for reading and the cycle repeats.
 **
-** The presence of a busy handler does not guarantee that
-** it will be invoked when there is lock contention.
-** If SQLite determines that invoking the busy handler could result in
-** a deadlock, it will go ahead and return [SQLITE_BUSY] or
-** [SQLITE_IOERR_BLOCKED] instead of invoking the
-** busy handler.
+** The presence of a busy handler does not guarantee that it will be invoked
+** when there is lock contention. If SQLite determines that invoking the busy
+** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
+** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
 ** Consider a scenario where one process is holding a read lock that
 ** it is trying to promote to a reserved lock and
 ** a second process is holding a reserved lock that it is trying
@@ -1138,82 +1521,52 @@ int sqlite3_complete16(const void *sql);
 ** code is promoted from the relatively benign [SQLITE_BUSY] to
 ** the more severe [SQLITE_IOERR_BLOCKED].  This error code promotion
 ** forces an automatic rollback of the changes.  See the
-** <a href="http://www.sqlite.org/cvstrac/wiki?p=CorruptionFollowingBusyError">
+** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
 ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
 ** this is important.
-**	
-** There can only be a single busy handler defined for each database
-** connection.  Setting a new busy handler clears any previous one. 
-** Note that calling [sqlite3_busy_timeout()] will also set or clear
-** the busy handler.
-**
-** INVARIANTS:
-**
-** {F12311} The [sqlite3_busy_handler()] function replaces the busy handler
-**          callback in the database connection identified by the 1st
-**          parameter with a new busy handler identified by the 2nd and 3rd
-**          parameters.
-**
-** {F12312} The default busy handler for new database connections is NULL.
 **
-** {F12314} When two or more database connection share a common cache,
-**          the busy handler for the database connection currently using
-**          the cache is invoked when the cache encounters a lock.
+** There can only be a single busy handler defined for each
+** [database connection].  Setting a new busy handler clears any
+** previously set handler.  Note that calling [sqlite3_busy_timeout()]
+** will also set or clear the busy handler.
 **
-** {F12316} If a busy handler callback returns zero, then the SQLite
-**          interface that provoked the locking event will return
-**          [SQLITE_BUSY].
-**
-** {F12318} SQLite will invokes the busy handler with two argument which
-**          are a copy of the pointer supplied by the 3rd parameter to
-**          [sqlite3_busy_handler()] and a count of the number of prior
-**          invocations of the busy handler for the same locking event.
-**
-** LIMITATIONS:
+** The busy callback should not take any actions which modify the
+** database connection that invoked the busy handler.  Any such actions
+** result in undefined behavior.
+** 
+** Requirements:
+** [H12311] [H12312] [H12314] [H12316] [H12318]
 **
-** {U12319} A busy handler should not call close the database connection
-**          or prepared statement that invoked the busy handler.
+** A busy handler must not close the database connection
+** or [prepared statement] that invoked the busy handler.
 */
-int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
+SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
 
 /*
-** CAPI3REF: Set A Busy Timeout {F12340}
+** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
 **
-** This routine sets a [sqlite3_busy_handler | busy handler]
-** that sleeps for a while when a
-** table is locked.  The handler will sleep multiple times until 
-** at least "ms" milliseconds of sleeping have been done. {F12343} After
-** "ms" milliseconds of sleeping, the handler returns 0 which
-** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
+** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
+** for a specified amount of time when a table is locked.  The handler
+** will sleep multiple times until at least "ms" milliseconds of sleeping
+** have accumulated. {H12343} After "ms" milliseconds of sleeping,
+** the handler returns 0 which causes [sqlite3_step()] to return
+** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
 **
 ** Calling this routine with an argument less than or equal to zero
 ** turns off all busy handlers.
 **
-** There can only be a single busy handler for a particular database
-** connection.  If another busy handler was defined  
-** (using [sqlite3_busy_handler()]) prior to calling
+** There can only be a single busy handler for a particular
+** [database connection] any any given moment.  If another busy handler
+** was defined  (using [sqlite3_busy_handler()]) prior to calling
 ** this routine, that other busy handler is cleared.
 **
-** INVARIANTS:
-**
-** {F12341} The [sqlite3_busy_timeout()] function overrides any prior
-**          [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
-**          on the same database connection.
-**
-** {F12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
-**          or equal to zero, then the busy handler is cleared so that
-**          all subsequent locking events immediately return [SQLITE_BUSY].
-**
-** {F12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
-**          number N, then a busy handler is set that repeatedly calls
-**          the xSleep() method in the VFS interface until either the
-**          lock clears or until the cumulative sleep time reported back
-**          by xSleep() exceeds N milliseconds.
+** Requirements:
+** [H12341] [H12343] [H12344]
 */
-int sqlite3_busy_timeout(sqlite3*, int ms);
+SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
 
 /*
-** CAPI3REF: Convenience Routines For Running Queries {F12370}
+** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
 **
 ** Definition: A <b>result table</b> is memory data structure created by the
 ** [sqlite3_get_table()] interface.  A result table records the
@@ -1224,16 +1577,14 @@ int sqlite3_busy_timeout(sqlite3*, int ms);
 ** numbers are obtained separately.  Let N be the number of rows
 ** and M be the number of columns.
 **
-** A result table is an array of pointers to zero-terminated
-** UTF-8 strings.  There are (N+1)*M elements in the array.  
-** The first M pointers point to zero-terminated strings that 
-** contain the names of the columns.
-** The remaining entries all point to query results.  NULL
-** values are give a NULL pointer.  All other values are in
-** their UTF-8 zero-terminated string representation as returned by
-** [sqlite3_column_text()].
+** A result table is an array of pointers to zero-terminated UTF-8 strings.
+** There are (N+1)*M elements in the array.  The first M pointers point
+** to zero-terminated strings that  contain the names of the columns.
+** The remaining entries all point to query results.  NULL values result
+** in NULL pointers.  All other values are in their UTF-8 zero-terminated
+** string representation as returned by [sqlite3_column_text()].
 **
-** A result table might consists of one or more memory allocations.
+** A result table might consist of one or more memory allocations.
 ** It is not safe to pass a result table directly to [sqlite3_free()].
 ** A result table should be deallocated using [sqlite3_free_table()].
 **
@@ -1268,11 +1619,11 @@ int sqlite3_busy_timeout(sqlite3*, int ms);
 ** string of its 2nd parameter.  It returns a result table to the
 ** pointer given in its 3rd parameter.
 **
-** After the calling function has finished using the result, it should 
-** pass the pointer to the result table to sqlite3_free_table() in order to 
-** release the memory that was malloc-ed.  Because of the way the 
+** After the calling function has finished using the result, it should
+** pass the pointer to the result table to sqlite3_free_table() in order to
+** release the memory that was malloced.  Because of the way the
 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
-** function must not try to call [sqlite3_free()] directly.  Only 
+** function must not try to call [sqlite3_free()] directly.  Only
 ** [sqlite3_free_table()] is able to release the memory properly and safely.
 **
 ** The sqlite3_get_table() interface is implemented as a wrapper around
@@ -1280,51 +1631,31 @@ int sqlite3_busy_timeout(sqlite3*, int ms);
 ** to any internal data structures of SQLite.  It uses only the public
 ** interface defined here.  As a consequence, errors that occur in the
 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
-** reflected in subsequent calls to [sqlite3_errcode()] or
-** [sqlite3_errmsg()].
-**
-** INVARIANTS:
-**
-** {F12371} If a [sqlite3_get_table()] fails a memory allocation, then
-**          it frees the result table under construction, aborts the
-**          query in process, skips any subsequent queries, sets the
-**          *resultp output pointer to NULL and returns [SQLITE_NOMEM].
-**
-** {F12373} If the ncolumn parameter to [sqlite3_get_table()] is not NULL
-**          then [sqlite3_get_table()] write the number of columns in the
-**          result set of the query into *ncolumn if the query is
-**          successful (if the function returns SQLITE_OK).
-**
-** {F12374} If the nrow parameter to [sqlite3_get_table()] is not NULL
-**          then [sqlite3_get_table()] write the number of rows in the
-**          result set of the query into *nrow if the query is
-**          successful (if the function returns SQLITE_OK).
-**
-** {F12376} The [sqlite3_get_table()] function sets its *ncolumn value
-**          to the number of columns in the result set of the query in the
-**          sql parameter, or to zero if the query in sql has an empty
-**          result set.
-*/
-int sqlite3_get_table(
-  sqlite3*,             /* An open database */
-  const char *sql,      /* SQL to be evaluated */
-  char ***pResult,      /* Results of the query */
-  int *nrow,            /* Number of result rows written here */
-  int *ncolumn,         /* Number of result columns written here */
-  char **errmsg         /* Error msg written here */
+** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
+**
+** Requirements:
+** [H12371] [H12373] [H12374] [H12376] [H12379] [H12382]
+*/
+SQLITE_API int sqlite3_get_table(
+  sqlite3 *db,          /* An open database */
+  const char *zSql,     /* SQL to be evaluated */
+  char ***pazResult,    /* Results of the query */
+  int *pnRow,           /* Number of result rows written here */
+  int *pnColumn,        /* Number of result columns written here */
+  char **pzErrmsg       /* Error msg written here */
 );
-void sqlite3_free_table(char **result);
+SQLITE_API void sqlite3_free_table(char **result);
 
 /*
-** CAPI3REF: Formatted String Printing Functions {F17400}
+** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
 **
-** These routines are workalikes of the "printf()" family of functions
+** These routines are work-alikes of the "printf()" family of functions
 ** from the standard C library.
 **
 ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
 ** results into memory obtained from [sqlite3_malloc()].
 ** The strings returned by these two routines should be
-** released by [sqlite3_free()].   Both routines return a
+** released by [sqlite3_free()].  Both routines return a
 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
 ** memory to hold the resulting string.
 **
@@ -1349,7 +1680,7 @@ void sqlite3_free_table(char **result);
 **
 ** These routines all implement some additional formatting
 ** options that are useful for constructing SQL statements.
-** All of the usual printf formatting options apply.  In addition, there
+** All of the usual printf() formatting options apply.  In addition, there
 ** is are "%q", "%Q", and "%z" options.
 **
 ** The %q option works like %s in that it substitutes a null-terminated
@@ -1358,7 +1689,7 @@ void sqlite3_free_table(char **result);
 ** character it escapes that character and allows it to be inserted into
 ** the string.
 **
-** For example, so some string variable contains text as follows:
+** For example, assume the string variable zText contains text as follows:
 **
 ** <blockquote><pre>
 **  char *zText = "It's a happy day!";
@@ -1386,14 +1717,13 @@ void sqlite3_free_table(char **result);
 **  INSERT INTO table1 VALUES('It's a happy day!');
 ** </pre></blockquote>
 **
-** This second example is an SQL syntax error.  As a general rule you
-** should always use %q instead of %s when inserting text into a string 
-** literal.
+** This second example is an SQL syntax error.  As a general rule you should
+** always use %q instead of %s when inserting text into a string literal.
 **
 ** The %Q option works like %q except it also adds single quotes around
-** the outside of the total string.  Or if the parameter in the argument
-** list is a NULL pointer, %Q substitutes the text "NULL" (without single
-** quotes) in place of the %Q option. {END}  So, for example, one could say:
+** the outside of the total string.  Additionally, if the parameter in the
+** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
+** single quotes) in place of the %Q option.  So, for example, one could say:
 **
 ** <blockquote><pre>
 **  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
@@ -1408,35 +1738,20 @@ void sqlite3_free_table(char **result);
 ** addition that after the string has been read and copied into
 ** the result, [sqlite3_free()] is called on the input string. {END}
 **
-** INVARIANTS:
-**
-** {F17403}  The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
-**           return either pointers to zero-terminated UTF-8 strings held in
-**           memory obtained from [sqlite3_malloc()] or NULL pointers if
-**           a call to [sqlite3_malloc()] fails.
-**
-** {F17406}  The [sqlite3_snprintf()] interface writes a zero-terminated
-**           UTF-8 string into the buffer pointed to by the second parameter
-**           provided that the first parameter is greater than zero.
-**
-** {F17407}  The [sqlite3_snprintf()] interface does not writes slots of
-**           its output buffer (the second parameter) outside the range
-**           of 0 through N-1 (where N is the first parameter)
-**           regardless of the length of the string
-**           requested by the format specification.
-**   
+** Requirements:
+** [H17403] [H17406] [H17407]
 */
-char *sqlite3_mprintf(const char*,...);
-char *sqlite3_vmprintf(const char*, va_list);
-char *sqlite3_snprintf(int,char*,const char*, ...);
+SQLITE_API char *sqlite3_mprintf(const char*,...);
+SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
+SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 
 /*
-** CAPI3REF: Memory Allocation Subsystem {F17300}
+** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
 **
 ** The SQLite core  uses these three routines for all of its own
 ** internal memory allocation needs. "Core" in the previous sentence
 ** does not include operating-system specific VFS implementation.  The
-** windows VFS uses native malloc and free for some operations.
+** Windows VFS uses native malloc() and free() for some operations.
 **
 ** The sqlite3_malloc() routine returns a pointer to a block
 ** of memory at least N bytes in length, where N is the parameter.
@@ -1454,7 +1769,7 @@ char *sqlite3_snprintf(int,char*,const char*, ...);
 ** memory might result in a segmentation fault or other severe error.
 ** Memory corruption, a segmentation fault, or other severe error
 ** might result if sqlite3_free() is called with a non-NULL pointer that
-** was not obtained from sqlite3_malloc() or sqlite3_free().
+** was not obtained from sqlite3_malloc() or sqlite3_realloc().
 **
 ** The sqlite3_realloc() interface attempts to resize a
 ** prior memory allocation to be at least N bytes, where N is the
@@ -1465,7 +1780,7 @@ char *sqlite3_snprintf(int,char*,const char*, ...);
 ** If the second parameter to sqlite3_realloc() is zero or
 ** negative then the behavior is exactly the same as calling
 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
-** Sqlite3_realloc() returns a pointer to a memory allocation
+** sqlite3_realloc() returns a pointer to a memory allocation
 ** of at least N bytes in size or NULL if sufficient memory is unavailable.
 ** If M is the size of the prior allocation, then min(N,M) bytes
 ** of the prior allocation are copied into the beginning of buffer returned
@@ -1476,128 +1791,66 @@ char *sqlite3_snprintf(int,char*,const char*, ...);
 ** The memory returned by sqlite3_malloc() and sqlite3_realloc()
 ** is always aligned to at least an 8 byte boundary. {END}
 **
-** The default implementation
-** of the memory allocation subsystem uses the malloc(), realloc()
-** and free() provided by the standard C library. {F17382} However, if 
-** SQLite is compiled with the following C preprocessor macro
-**
-** <blockquote> SQLITE_MEMORY_SIZE=<i>NNN</i> </blockquote>
-**
-** where <i>NNN</i> is an integer, then SQLite create a static
-** array of at least <i>NNN</i> bytes in size and use that array
-** for all of its dynamic memory allocation needs. {END}  Additional
-** memory allocator options may be added in future releases.
+** The default implementation of the memory allocation subsystem uses
+** the malloc(), realloc() and free() provided by the standard C library.
+** {H17382} However, if SQLite is compiled with the
+** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
+** is an integer), then SQLite create a static array of at least
+** <i>NNN</i> bytes in size and uses that array for all of its dynamic
+** memory allocation needs. {END}  Additional memory allocator options
+** may be added in future releases.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
 ** implementation of these routines to be omitted.  That capability
-** is no longer provided.  Only built-in memory allocators can be
-** used.
+** is no longer provided.  Only built-in memory allocators can be used.
 **
-** The windows OS interface layer calls
+** The Windows OS interface layer calls
 ** the system malloc() and free() directly when converting
 ** filenames between the UTF-8 encoding used by SQLite
-** and whatever filename encoding is used by the particular windows
+** and whatever filename encoding is used by the particular Windows
 ** installation.  Memory allocation errors are detected, but
 ** they are reported back as [SQLITE_CANTOPEN] or
 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
 **
-** INVARIANTS:
-**
-** {F17303}  The [sqlite3_malloc(N)] interface returns either a pointer to 
-**           newly checked-out block of at least N bytes of memory
-**           that is 8-byte aligned, 
-**           or it returns NULL if it is unable to fulfill the request.
-**
-** {F17304}  The [sqlite3_malloc(N)] interface returns a NULL pointer if
-**           N is less than or equal to zero.
-**
-** {F17305}  The [sqlite3_free(P)] interface releases memory previously
-**           returned from [sqlite3_malloc()] or [sqlite3_realloc()],
-**           making it available for reuse.
-**
-** {F17306}  A call to [sqlite3_free(NULL)] is a harmless no-op.
-**
-** {F17310}  A call to [sqlite3_realloc(0,N)] is equivalent to a call
-**           to [sqlite3_malloc(N)].
-**
-** {F17312}  A call to [sqlite3_realloc(P,0)] is equivalent to a call
-**           to [sqlite3_free(P)].
-**
-** {F17315}  The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
-**           and [sqlite3_free()] for all of its memory allocation and
-**           deallocation needs.
+** Requirements:
+** [H17303] [H17304] [H17305] [H17306] [H17310] [H17312] [H17315] [H17318]
+** [H17321] [H17322] [H17323]
 **
-** {F17318}  The [sqlite3_realloc(P,N)] interface returns either a pointer
-**           to a block of checked-out memory of at least N bytes in size
-**           that is 8-byte aligned, or a NULL pointer.
-**
-** {F17321}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
-**           copies the first K bytes of content from P into the newly allocated
-**           where K is the lessor of N and the size of the buffer P.
-**
-** {F17322}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
-**           releases the buffer P.
-**
-** {F17323}  When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
-**           not modified or released.
-**
-** LIMITATIONS:
-**
-** {U17350}  The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
-**           must be either NULL or else a pointer obtained from a prior
-**           invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that has
-**           not been released.
-**
-** {U17351}  The application must not read or write any part of 
-**           a block of memory after it has been released using
-**           [sqlite3_free()] or [sqlite3_realloc()].
+** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+** must be either NULL or else pointers obtained from a prior
+** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+** not yet been released.
 **
+** The application must not read or write any part of
+** a block of memory after it has been released using
+** [sqlite3_free()] or [sqlite3_realloc()].
 */
-void *sqlite3_malloc(int);
-void *sqlite3_realloc(void*, int);
-void sqlite3_free(void*);
+SQLITE_API void *sqlite3_malloc(int);
+SQLITE_API void *sqlite3_realloc(void*, int);
+SQLITE_API void sqlite3_free(void*);
 
 /*
-** CAPI3REF: Memory Allocator Statistics {F17370}
+** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
 **
 ** SQLite provides these two interfaces for reporting on the status
 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
-** the memory allocation subsystem included within the SQLite.
-**
-** INVARIANTS:
-**
-** {F17371} The [sqlite3_memory_used()] routine returns the
-**          number of bytes of memory currently outstanding 
-**          (malloced but not freed).
+** routines, which form the built-in memory allocation subsystem.
 **
-** {F17373} The [sqlite3_memory_highwater()] routine returns the maximum
-**          value of [sqlite3_memory_used()] 
-**          since the highwater mark was last reset.
-**
-** {F17374} The values returned by [sqlite3_memory_used()] and
-**          [sqlite3_memory_highwater()] include any overhead
-**          added by SQLite in its implementation of [sqlite3_malloc()],
-**          but not overhead added by the any underlying system library
-**          routines that [sqlite3_malloc()] may call.
-** 
-** {F17375} The memory highwater mark is reset to the current value of
-**          [sqlite3_memory_used()] if and only if the parameter to
-**          [sqlite3_memory_highwater()] is true.  The value returned
-**          by [sqlite3_memory_highwater(1)] is the highwater mark
-**          prior to the reset.
+** Requirements:
+** [H17371] [H17373] [H17374] [H17375]
 */
-sqlite3_int64 sqlite3_memory_used(void);
-sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 
 /*
-** CAPI3REF: Pseudo-Random Number Generator {F17390}
+** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
 **
 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
-** select random ROWIDs when inserting new records into a table that
-** already uses the largest possible ROWID.  The PRNG is also used for
+** select random [ROWID | ROWIDs] when inserting new records into a table that
+** already uses the largest possible [ROWID].  The PRNG is also used for
 ** the build-in random() and randomblob() SQL functions.  This interface allows
-** appliations to access the same PRNG for other purposes.
+** applications to access the same PRNG for other purposes.
 **
 ** A call to this routine stores N bytes of randomness into buffer P.
 **
@@ -1608,15 +1861,13 @@ sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 ** internally and without recourse to the [sqlite3_vfs] xRandomness
 ** method.
 **
-** INVARIANTS:
-**
-** {F17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
-**          high-quality pseudo-randomness into buffer P.
+** Requirements:
+** [H17392]
 */
-void sqlite3_randomness(int N, void *P);
+SQLITE_API void sqlite3_randomness(int N, void *P);
 
 /*
-** CAPI3REF: Compile-Time Authorization Callbacks {F12500}
+** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
 **
 ** This routine registers a authorizer callback with a particular
 ** [database connection], supplied in the first argument.
@@ -1629,36 +1880,39 @@ void sqlite3_randomness(int N, void *P);
 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
 ** specific action but allow the SQL statement to continue to be
 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
-** rejected with an error.   If the authorizer callback returns
+** rejected with an error.  If the authorizer callback returns
 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
-** then [sqlite3_prepare_v2()] or equivalent call that triggered
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
 ** the authorizer will fail with an error message.
 **
 ** When the callback returns [SQLITE_OK], that means the operation
 ** requested is ok.  When the callback returns [SQLITE_DENY], the
 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
 ** authorizer will fail with an error message explaining that
-** access is denied.  If the authorizer code is [SQLITE_READ]
+** access is denied. 
+**
+** The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. The third through sixth parameters
+** to the callback are zero-terminated strings that contain additional
+** details about the action to be authorized.
+**
+** If the action code is [SQLITE_READ]
 ** and the callback returns [SQLITE_IGNORE] then the
 ** [prepared statement] statement is constructed to substitute
 ** a NULL value in place of the table column that would have
 ** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
 ** return can be used to deny an untrusted user access to individual
 ** columns of a table.
-**
-** The first parameter to the authorizer callback is a copy of
-** the third parameter to the sqlite3_set_authorizer() interface.
-** The second parameter to the callback is an integer 
-** [SQLITE_COPY | action code] that specifies the particular action
-** to be authorized. The third through sixth
-** parameters to the callback are zero-terminated strings that contain 
-** additional details about the action to be authorized.
+** If the action code is [SQLITE_DELETE] and the callback returns
+** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
+** [truncate optimization] is disabled and all rows are deleted individually.
 **
 ** An authorizer is used when [sqlite3_prepare | preparing]
-** SQL statements from an untrusted
-** source, to ensure that the SQL statements do not try to access data
-** that they are not allowed to see, or that they do not try to
-** execute malicious statements that damage the database.  For
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database.  For
 ** example, an application may allow a user to enter arbitrary
 ** SQL queries for evaluation by a database.  But the application does
 ** not want the user to be able to make arbitrary changes to the
@@ -1676,70 +1930,34 @@ void sqlite3_randomness(int N, void *P);
 ** previous call.  Disable the authorizer by installing a NULL callback.
 ** The authorizer is disabled by default.
 **
-** Note that the authorizer callback is invoked only during 
-** [sqlite3_prepare()] or its variants.  Authorization is not
-** performed during statement evaluation in [sqlite3_step()].
-**
-** INVARIANTS:
-**
-** {F12501} The [sqlite3_set_authorizer(D,...)] interface registers a
-**          authorizer callback with database connection D.
-**
-** {F12502} The authorizer callback is invoked as SQL statements are
-**          being compiled
-**
-** {F12503} If the authorizer callback returns any value other than
-**          [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] then
-**          the [sqlite3_prepare_v2()] or equivalent call that caused
-**          the authorizer callback to run shall fail with an
-**          [SQLITE_ERROR] error code and an appropriate error message.
-**
-** {F12504} When the authorizer callback returns [SQLITE_OK], the operation
-**          described is coded normally.
-**
-** {F12505} When the authorizer callback returns [SQLITE_DENY], the
-**          [sqlite3_prepare_v2()] or equivalent call that caused the
-**          authorizer callback to run shall fail
-**          with an [SQLITE_ERROR] error code and an error message
-**          explaining that access is denied.
-**
-** {F12506} If the authorizer code (the 2nd parameter to the authorizer
-**          callback) is [SQLITE_READ] and the authorizer callback returns
-**          [SQLITE_IGNORE] then the prepared statement is constructed to
-**          insert a NULL value in place of the table column that would have
-**          been read if [SQLITE_OK] had been returned.
-**
-** {F12507} If the authorizer code (the 2nd parameter to the authorizer
-**          callback) is anything other than [SQLITE_READ], then
-**          a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY]. 
-**
-** {F12510} The first parameter to the authorizer callback is a copy of
-**          the third parameter to the [sqlite3_set_authorizer()] interface.
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12511} The second parameter to the callback is an integer 
-**          [SQLITE_COPY | action code] that specifies the particular action
-**          to be authorized.
+** When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be re-prepared during [sqlite3_step()] due to a 
+** schema change.  Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
 **
-** {F12512} The third through sixth parameters to the callback are
-**          zero-terminated strings that contain 
-**          additional details about the action to be authorized.
-**
-** {F12520} Each call to [sqlite3_set_authorizer()] overrides the
-**          any previously installed authorizer.
-**
-** {F12521} A NULL authorizer means that no authorization
-**          callback is invoked.
+** Note that the authorizer callback is invoked only during
+** [sqlite3_prepare()] or its variants.  Authorization is not
+** performed during statement evaluation in [sqlite3_step()], unless
+** as stated in the previous paragraph, sqlite3_step() invokes
+** sqlite3_prepare_v2() to reprepare a statement after a schema change.
 **
-** {F12522} The default authorizer is NULL.
+** Requirements:
+** [H12501] [H12502] [H12503] [H12504] [H12505] [H12506] [H12507] [H12510]
+** [H12511] [H12512] [H12520] [H12521] [H12522]
 */
-int sqlite3_set_authorizer(
+SQLITE_API int sqlite3_set_authorizer(
   sqlite3*,
   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
   void *pUserData
 );
 
 /*
-** CAPI3REF: Authorizer Return Codes {F12590}
+** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
 **
 ** The [sqlite3_set_authorizer | authorizer callback function] must
 ** return either [SQLITE_OK] or one of these two constants in order
@@ -1751,45 +1969,26 @@ int sqlite3_set_authorizer(
 #define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
 
 /*
-** CAPI3REF: Authorizer Action Codes {F12550}
+** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
 **
 ** The [sqlite3_set_authorizer()] interface registers a callback function
-** that is invoked to authorizer certain SQL statement actions.  The
+** that is invoked to authorize certain SQL statement actions.  The
 ** second parameter to the callback is an integer code that specifies
 ** what action is being authorized.  These are the integer action codes that
 ** the authorizer callback may be passed.
 **
-** These action code values signify what kind of operation is to be 
+** These action code values signify what kind of operation is to be
 ** authorized.  The 3rd and 4th parameters to the authorization
 ** callback function will be parameters or NULL depending on which of these
 ** codes is used as the second parameter.  The 5th parameter to the
-** authorizer callback is the name of the database ("main", "temp", 
+** authorizer callback is the name of the database ("main", "temp",
 ** etc.) if applicable.  The 6th parameter to the authorizer callback
 ** is the name of the inner-most trigger or view that is responsible for
-** the access attempt or NULL if this access attempt is directly from 
+** the access attempt or NULL if this access attempt is directly from
 ** top-level SQL code.
 **
-** INVARIANTS:
-**
-** {F12551} The second parameter to an 
-**          [sqlite3_set_authorizer | authorizer callback is always an integer
-**          [SQLITE_COPY | authorizer code] that specifies what action
-**          is being authorized.
-**
-** {F12552} The 3rd and 4th parameters to the 
-**          [sqlite3_set_authorizer | authorization callback function]
-**          will be parameters or NULL depending on which 
-**          [SQLITE_COPY | authorizer code] is used as the second parameter.
-**
-** {F12553} The 5th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
-**          of the database (example: "main", "temp", etc.) if applicable.
-**
-** {F12554} The 6th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
-**          of the inner-most trigger or view that is responsible for
-**          the access attempt or NULL if this access attempt is directly from 
-**          top-level SQL code.
+** Requirements:
+** [H12551] [H12552] [H12553] [H12554]
 */
 /******************************************* 3rd ************ 4th ***********/
 #define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
@@ -1813,7 +2012,7 @@ int sqlite3_set_authorizer(
 #define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
 #define SQLITE_READ                 20   /* Table Name      Column Name     */
 #define SQLITE_SELECT               21   /* NULL            NULL            */
-#define SQLITE_TRANSACTION          22   /* NULL            NULL            */
+#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
 #define SQLITE_UPDATE               23   /* Table Name      Column Name     */
 #define SQLITE_ATTACH               24   /* Filename        NULL            */
 #define SQLITE_DETACH               25   /* Database Name   NULL            */
@@ -1822,11 +2021,13 @@ int sqlite3_set_authorizer(
 #define SQLITE_ANALYZE              28   /* Table Name      NULL            */
 #define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
 #define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
-#define SQLITE_FUNCTION             31   /* Function Name   NULL            */
+#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
+#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
 #define SQLITE_COPY                  0   /* No longer used */
 
 /*
-** CAPI3REF: Tracing And Profiling Functions {F12280}
+** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
+** EXPERIMENTAL
 **
 ** These routines register callback functions that can be used for
 ** tracing and profiling the execution of SQL statements.
@@ -1835,255 +2036,146 @@ int sqlite3_set_authorizer(
 ** various times when an SQL statement is being run by [sqlite3_step()].
 ** The callback returns a UTF-8 rendering of the SQL statement text
 ** as the statement first begins executing.  Additional callbacks occur
-** as each triggersubprogram is entered.  The callbacks for triggers
+** as each triggered subprogram is entered.  The callbacks for triggers
 ** contain a UTF-8 SQL comment that identifies the trigger.
-** 
+**
 ** The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  The profile callback contains
 ** the original statement text and an estimate of wall-clock time
 ** of how long that statement took to run.
 **
-** The sqlite3_profile() API is currently considered experimental and
-** is subject to change or removal in a future release.
-**
-** The trigger reporting feature of the trace callback is considered
-** experimental and is subject to change or removal in future releases.
-** Future versions of SQLite might also add new trace callback 
-** invocations.
-**
-** INVARIANTS:
-**
-** {F12281} The callback function registered by [sqlite3_trace()] is
-**          whenever an SQL statement first begins to execute and
-**          whenever a trigger subprogram first begins to run.
-**
-** {F12282} Each call to [sqlite3_trace()] overrides the previously
-**          registered trace callback.
-**
-** {F12283} A NULL trace callback disables tracing.
-**
-** {F12284} The first argument to the trace callback is a copy of
-**          the pointer which was the 3rd argument to [sqlite3_trace()].
-**
-** {F12285} The second argument to the trace callback is a
-**          zero-terminated UTF8 string containing the original text
-**          of the SQL statement as it was passed into [sqlite3_prepare_v2()]
-**          or the equivalent, or an SQL comment indicating the beginning
-**          of a trigger subprogram.
-**
-** {F12287} The callback function registered by [sqlite3_profile()] is invoked
-**          as each SQL statement finishes.
-**
-** {F12288} The first parameter to the profile callback is a copy of
-**          the 3rd parameter to [sqlite3_profile()].
-**
-** {F12289} The second parameter to the profile callback is a
-**          zero-terminated UTF-8 string that contains the complete text of
-**          the SQL statement as it was processed by [sqlite3_prepare_v2()]
-**          or the equivalent.
-**
-** {F12290} The third parameter to the profile  callback is an estimate
-**          of the number of nanoseconds of wall-clock time required to
-**          run the SQL statement from start to finish.
+** Requirements:
+** [H12281] [H12282] [H12283] [H12284] [H12285] [H12287] [H12288] [H12289]
+** [H12290]
 */
-void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
-void *sqlite3_profile(sqlite3*,
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
    void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
 
 /*
-** CAPI3REF: Query Progress Callbacks {F12910}
+** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
 **
 ** This routine configures a callback function - the
 ** progress callback - that is invoked periodically during long
 ** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].   An example use for this 
+** [sqlite3_get_table()].  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
-** If the progress callback returns non-zero, the opertion is
+** If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
-** "Cancel" button on a GUI dialog box.
-**
-** INVARIANTS:
-**
-** {F12911} The callback function registered by [sqlite3_progress_handler()]
-**          is invoked periodically during long running calls to
-**          [sqlite3_step()].
-**
-** {F12912} The progress callback is invoked once for every N virtual
-**          machine opcodes, where N is the second argument to 
-**          the [sqlite3_progress_handler()] call that registered
-**          the callback.  <todo>What if N is less than 1?</todo>
-**
-** {F12913} The progress callback itself is identified by the third
-**          argument to [sqlite3_progress_handler()].
+** "Cancel" button on a GUI progress dialog box.
 **
-** {F12914} The fourth argument [sqlite3_progress_handler()] is a
-***         void pointer passed to the progress callback
-**          function each time it is invoked.
+** The progress handler must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12915} If a call to [sqlite3_step()] results in fewer than
-**          N opcodes being executed,
-**          then the progress callback is never invoked. {END}
-** 
-** {F12916} Every call to [sqlite3_progress_handler()]
-**          overwrites any previously registere progress handler.
-**
-** {F12917} If the progress handler callback is NULL then no progress
-**          handler is invoked.
+** Requirements:
+** [H12911] [H12912] [H12913] [H12914] [H12915] [H12916] [H12917] [H12918]
 **
-** {F12918} If the progress callback returns a result other than 0, then
-**          the behavior is a if [sqlite3_interrupt()] had been called.
 */
-void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
+SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 
 /*
-** CAPI3REF: Opening A New Database Connection {F12700}
-**
-** These routines open an SQLite database file whose name
-** is given by the filename argument.
-** The filename argument is interpreted as UTF-8
-** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
-** in the native byte order for [sqlite3_open16()].
-** An [sqlite3*] handle is usually returned in *ppDb, even
-** if an error occurs.  The only exception is if SQLite is unable
-** to allocate memory to hold the [sqlite3] object, a NULL will
-** be written into *ppDb instead of a pointer to the [sqlite3] object.
-** If the database is opened (and/or created)
-** successfully, then [SQLITE_OK] is returned.  Otherwise an
-** error code is returned.  The
-** [sqlite3_errmsg()] or [sqlite3_errmsg16()]  routines can be used to obtain
+** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
+**
+** These routines open an SQLite database file whose name is given by the
+** filename argument. The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs.  The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object. If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.  The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
 ** an English language description of the error.
 **
 ** The default encoding for the database will be UTF-8 if
-** [sqlite3_open()] or [sqlite3_open_v2()] is called and
-** UTF-16 in the native byte order if [sqlite3_open16()] is used.
+** sqlite3_open() or sqlite3_open_v2() is called and
+** UTF-16 in the native byte order if sqlite3_open16() is used.
 **
 ** Whether or not an error occurs when it is opened, resources
-** associated with the [sqlite3*] handle should be released by passing it
-** to [sqlite3_close()] when it is no longer required.
+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
 **
-** The [sqlite3_open_v2()] interface works like [sqlite3_open()] 
-** except that it acccepts two additional parameters for additional control
-** over the new database connection.  The flags parameter can be
-** one of:
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection.  The flags parameter can take one of
+** the following three values, optionally combined with the 
+** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
+** and/or [SQLITE_OPEN_PRIVATECACHE] flags:
 **
-** <ol>
-** <li>  [SQLITE_OPEN_READONLY]
-** <li>  [SQLITE_OPEN_READWRITE]
-** <li>  [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
-** </ol>
+** <dl>
+** <dt>[SQLITE_OPEN_READONLY]</dt>
+** <dd>The database is opened in read-only mode.  If the database does not
+** already exist, an error is returned.</dd>
+**
+** <dt>[SQLITE_OPEN_READWRITE]</dt>
+** <dd>The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system.  In either
+** case the database must already exist, otherwise an error is returned.</dd>
+**
+** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
+** <dd>The database is opened for reading and writing, and is creates it if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().</dd>
+** </dl>
+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above or one of the combinations shown above combined
+** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
+** then the behavior is undefined.
 **
-** The first value opens the database read-only. 
-** If the database does not previously exist, an error is returned.
-** The second option opens
-** the database for reading and writing if possible, or reading only if
-** if the file is write protected.  In either case the database
-** must already exist or an error is returned.  The third option
-** opens the database for reading and writing and creates it if it does
-** not already exist.
-** The third options is behavior that is always used for [sqlite3_open()]
-** and [sqlite3_open16()].
-**
-** If the 3rd parameter to [sqlite3_open_v2()] is not one of the
-** combinations shown above then the behavior is undefined.
-**
-** If the filename is ":memory:", then an private
-** in-memory database is created for the connection.  This in-memory
-** database will vanish when the database connection is closed.  Future
-** version of SQLite might make use of additional special filenames
-** that begin with the ":" character.  It is recommended that 
-** when a database filename really does begin with
-** ":" that you prefix the filename with a pathname like "./" to
-** avoid ambiguity.
-**
-** If the filename is an empty string, then a private temporary
+** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time.  If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+** The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
+** eligible to use [shared cache mode], regardless of whether or not shared
+** cache is enabled using [sqlite3_enable_shared_cache()].  The
+** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
+** participate in [shared cache mode] even if it is enabled.
+**
+** If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection.  This in-memory database will vanish when
+** the database connection is closed.  Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** If the filename is an empty string, then a private, temporary
 ** on-disk database will be created.  This private database will be
 ** automatically deleted as soon as the database connection is closed.
 **
 ** The fourth parameter to sqlite3_open_v2() is the name of the
-** [sqlite3_vfs] object that defines the operating system 
-** interface that the new database connection should use.  If the
-** fourth parameter is a NULL pointer then the default [sqlite3_vfs]
-** object is used.
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use.  If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
 **
-** <b>Note to windows users:</b>  The encoding used for the filename argument
-** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever
+** <b>Note to Windows users:</b>  The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
 ** codepage is currently defined.  Filenames containing international
 ** characters must be converted to UTF-8 prior to passing them into
-** [sqlite3_open()] or [sqlite3_open_v2()].
-**
-** INVARIANTS:
-**
-** {F12701} The [sqlite3_open()], [sqlite3_open16()], and
-**          [sqlite3_open_v2()] interfaces create a new
-**          [database connection] associated with
-**          the database file given in their first parameter.
-**
-** {F12702} The filename argument is interpreted as UTF-8
-**          for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
-**          in the native byte order for [sqlite3_open16()].
-**
-** {F12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()], 
-**          or [sqlite3_open_v2()] writes a pointer to a new
-**          [database connection] into *ppDb.
-**
-** {F12704} The [sqlite3_open()], [sqlite3_open16()], and
-**          [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
-**          or an appropriate [error code] on failure.
-**
-** {F12706} The default text encoding for a new database created using
-**          [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
-**
-** {F12707} The default text encoding for a new database created using
-**          [sqlite3_open16()] will be UTF-16.
+** sqlite3_open() or sqlite3_open_v2().
 **
-** {F12709} The [sqlite3_open(F,D)] interface is equivalent to
-**          [sqlite3_open_v2(F,D,G,0)] where the G parameter is
-**          [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
-**
-** {F12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_READONLY] then the database is opened
-**          for reading only.
-**
-** {F12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_READWRITE] then the database is opened
-**          reading and writing if possible, or for reading only if the
-**          file is write protected by the operating system.
-**
-** {F12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
-**          bit value [SQLITE_OPEN_CREATE] and the database does not
-**          previously exist, an error is returned.
-**
-** {F12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
-**          bit value [SQLITE_OPEN_CREATE] and the database does not
-**          previously exist, then an attempt is made to create and
-**          initialize the database.
-**
-** {F12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
-**          or [sqlite3_open_v2()] is ":memory:", then an private,
-**          ephemeral, in-memory database is created for the connection.
-**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
-**          in sqlite3_open_v2()?</todo>
-**
-** {F12719} If the filename is NULL or an empty string, then a private,
-**          ephermeral on-disk database will be created.
-**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
-**          in sqlite3_open_v2()?</todo>
-**
-** {F12721} The [database connection] created by 
-**          [sqlite3_open_v2(F,D,G,V)] will use the
-**          [sqlite3_vfs] object identified by the V parameter, or
-**          the default [sqlite3_vfs] object is V is a NULL pointer.
+** Requirements:
+** [H12701] [H12702] [H12703] [H12704] [H12706] [H12707] [H12709] [H12711]
+** [H12712] [H12713] [H12714] [H12717] [H12719] [H12721] [H12723]
 */
-int sqlite3_open(
+SQLITE_API int sqlite3_open(
   const char *filename,   /* Database filename (UTF-8) */
   sqlite3 **ppDb          /* OUT: SQLite db handle */
 );
-int sqlite3_open16(
+SQLITE_API int sqlite3_open16(
   const void *filename,   /* Database filename (UTF-16) */
   sqlite3 **ppDb          /* OUT: SQLite db handle */
 );
-int sqlite3_open_v2(
+SQLITE_API int sqlite3_open_v2(
   const char *filename,   /* Database filename (UTF-8) */
   sqlite3 **ppDb,         /* OUT: SQLite db handle */
   int flags,              /* Flags */
@@ -2091,68 +2183,61 @@ int sqlite3_open_v2(
 );
 
 /*
-** CAPI3REF: Error Codes And Messages {F12800}
+** CAPI3REF: Error Codes And Messages {H12800} <S60200>
 **
-** The sqlite3_errcode() interface returns the numeric
-** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code]
-** for the most recent failed sqlite3_* API call associated
-** with [sqlite3] handle 'db'. If a prior API call failed but the
-** most recent API call succeeded, the return value from sqlite3_errcode()
-** is undefined.
+** The sqlite3_errcode() interface returns the numeric [result code] or
+** [extended result code] for the most recent failed sqlite3_* API call
+** associated with a [database connection]. If a prior API call failed
+** but the most recent API call succeeded, the return value from
+** sqlite3_errcode() is undefined.  The sqlite3_extended_errcode()
+** interface is the same except that it always returns the 
+** [extended result code] even when extended result codes are
+** disabled.
 **
 ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
-** text that describes the error, as either UTF8 or UTF16 respectively.
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
 ** Memory to hold the error message string is managed internally.
-** The application does not need to worry with freeing the result.
+** The application does not need to worry about freeing the result.
 ** However, the error string might be overwritten or deallocated by
 ** subsequent calls to other SQLite interface functions.
 **
-** INVARIANTS:
-**
-** {F12801} The [sqlite3_errcode(D)] interface returns the numeric
-**          [SQLITE_OK | result code] or
-**          [SQLITE_IOERR_READ | extended result code]
-**          for the most recently failed interface call associated
-**          with [database connection] D.
-**
-** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
-**          interfaces return English-language text that describes
-**          the error in the mostly recently failed interface call,
-**          encoded as either UTF8 or UTF16 respectively.
-**
-** {F12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
-**          are valid until the next SQLite interface call.
-**
-** {F12808} Calls to API routines that do not return an error code
-**          (example: [sqlite3_data_count()]) do not
-**          change the error code or message returned by
-**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
-**
-** {F12809} Interfaces that are not associated with a specific
-**          [database connection] (examples:
-**          [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
-**          do not change the values returned by
-**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
+** When the serialized [threading mode] is in use, it might be the
+** case that a second error occurs on a separate thread in between
+** the time of the first error and the call to these interfaces.
+** When that happens, the second error will be reported since these
+** interfaces always report the most recent result.  To avoid
+** this, each thread can obtain exclusive use of the [database connection] D
+** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
+** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
+** all calls to the interfaces listed here are completed.
+**
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application.  In that case, the
+** error code and message may or may not be set.
+**
+** Requirements:
+** [H12801] [H12802] [H12803] [H12807] [H12808] [H12809]
 */
-int sqlite3_errcode(sqlite3 *db);
-const char *sqlite3_errmsg(sqlite3*);
-const void *sqlite3_errmsg16(sqlite3*);
+SQLITE_API int sqlite3_errcode(sqlite3 *db);
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
+SQLITE_API const char *sqlite3_errmsg(sqlite3*);
+SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
 
 /*
-** CAPI3REF: SQL Statement Object {F13000}
+** CAPI3REF: SQL Statement Object {H13000} <H13010>
 ** KEYWORDS: {prepared statement} {prepared statements}
 **
-** An instance of this object represent single SQL statements.  This
-** object is variously known as a "prepared statement" or a 
+** An instance of this object represents a single SQL statement.
+** This object is variously known as a "prepared statement" or a
 ** "compiled SQL statement" or simply as a "statement".
-** 
+**
 ** The life of a statement object goes something like this:
 **
 ** <ol>
 ** <li> Create the object using [sqlite3_prepare_v2()] or a related
 **      function.
-** <li> Bind values to host parameters using
-**      [sqlite3_bind_blob | sqlite3_bind_* interfaces].
+** <li> Bind values to [host parameters] using the sqlite3_bind_*()
+**      interfaces.
 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
 ** <li> Reset the statement using [sqlite3_reset()] then go back
 **      to step 2.  Do this zero or more times.
@@ -2165,7 +2250,7 @@ const void *sqlite3_errmsg16(sqlite3*);
 typedef struct sqlite3_stmt sqlite3_stmt;
 
 /*
-** CAPI3REF: Run-time Limits {F12760}
+** CAPI3REF: Run-time Limits {H12760} <S20600>
 **
 ** This interface allows the size of various constructs to be limited
 ** on a connection by connection basis.  The first parameter is the
@@ -2175,8 +2260,10 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** new limit for that construct.  The function returns the old limit.
 **
 ** If the new limit is a negative number, the limit is unchanged.
-** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
-** bound set by a compile-time C-preprocess macro named SQLITE_MAX_XYZ.
+** For the limit category of SQLITE_LIMIT_XYZ there is a 
+** [limits | hard upper bound]
+** set by a compile-time C preprocessor macro named 
+** [limits | SQLITE_MAX_XYZ].
 ** (The "_LIMIT_" in the name is changed to "_MAX_".)
 ** Attempts to increase a limit above its hard upper bound are
 ** silently truncated to the hard upper limit.
@@ -2184,55 +2271,42 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** Run time limits are intended for use in applications that manage
 ** both their own internal database and also databases that are controlled
 ** by untrusted external sources.  An example application might be a
-** webbrowser that has its own databases for storing history and
-** separate databases controlled by javascript applications downloaded
-** off the internet.  The internal databases can be given the
+** web browser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet.  The internal databases can be given the
 ** large, default limits.  Databases managed by external sources can
 ** be given much smaller limits designed to prevent a denial of service
-** attach.  Developers might also want to use the [sqlite3_set_authorizer()]
+** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
 ** interface to further control untrusted SQL.  The size of the database
 ** created by an untrusted script can be contained using the
 ** [max_page_count] [PRAGMA].
 **
-** This interface is currently considered experimental and is subject
-** to change or removal without prior notice.
-**
-** INVARIANTS:
+** New run-time limit categories may be added in future releases.
 **
-** {F12762} A successful call to [sqlite3_limit(D,C,V)] where V is
-**          positive changes the
-**          limit on the size of construct C in [database connection] D
-**          to the lessor of V and the hard upper bound on the size
-**          of C that is set at compile-time.
-**
-** {F12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
-**          leaves the state of [database connection] D unchanged.
-**
-** {F12769} A successful call to [sqlite3_limit(D,C,V)] returns the
-**          value of the limit on the size of construct C in
-**          in [database connection] D as it was prior to the call.
+** Requirements:
+** [H12762] [H12766] [H12769]
 */
-int sqlite3_limit(sqlite3*, int id, int newVal);
+SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 
 /*
-** CAPI3REF: Run-Time Limit Categories {F12790}
+** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
 ** KEYWORDS: {limit category} {limit categories}
-** 
-** These constants define various aspects of a [database connection]
-** that can be limited in size by calls to [sqlite3_limit()].
-** The meanings of the various limits are as follows:
+**
+** These constants define various performance limits
+** that can be lowered at run-time using [sqlite3_limit()].
+** The synopsis of the meanings of the various limits is shown below.
+** Additional information is available at [limits | Limits in SQLite].
 **
 ** <dl>
 ** <dt>SQLITE_LIMIT_LENGTH</dt>
-** <dd>The maximum size of any
-** string or blob or table row.<dd>
+** <dd>The maximum size of any string or BLOB or table row.<dd>
 **
 ** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
 ** <dd>The maximum length of an SQL statement.</dd>
 **
 ** <dt>SQLITE_LIMIT_COLUMN</dt>
 ** <dd>The maximum number of columns in a table definition or in the
-** result set of a SELECT or the maximum number of columns in an index
+** result set of a [SELECT] or the maximum number of columns in an index
 ** or in an ORDER BY or GROUP BY clause.</dd>
 **
 ** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
@@ -2249,15 +2323,18 @@ int sqlite3_limit(sqlite3*, int id, int newVal);
 ** <dd>The maximum number of arguments on a function.</dd>
 **
 ** <dt>SQLITE_LIMIT_ATTACHED</dt>
-** <dd>The maximum number of attached databases.</dd>
+** <dd>The maximum number of [ATTACH | attached databases].</dd>
 **
 ** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
-** <dd>The maximum length of the pattern argument to the LIKE or
-** GLOB operators.</dd>
+** <dd>The maximum length of the pattern argument to the [LIKE] or
+** [GLOB] operators.</dd>
 **
 ** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
 ** <dd>The maximum number of variables in an SQL statement that can
 ** be bound.</dd>
+**
+** <dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
+** <dd>The maximum depth of recursion for triggers.</dd>
 ** </dl>
 */
 #define SQLITE_LIMIT_LENGTH                    0
@@ -2270,54 +2347,55 @@ int sqlite3_limit(sqlite3*, int id, int newVal);
 #define SQLITE_LIMIT_ATTACHED                  7
 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
 #define SQLITE_LIMIT_VARIABLE_NUMBER           9
+#define SQLITE_LIMIT_TRIGGER_DEPTH            10
 
 /*
-** CAPI3REF: Compiling An SQL Statement {F13010}
+** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
+** KEYWORDS: {SQL statement compiler}
 **
 ** To execute an SQL query, it must first be compiled into a byte-code
-** program using one of these routines. 
+** program using one of these routines.
+**
+** The first argument, "db", is a [database connection] obtained from a
+** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
+** [sqlite3_open16()].  The database connection must not have been closed.
 **
-** The first argument "db" is an [database connection] 
-** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()]
-** or [sqlite3_open16()]. 
-** The second argument "zSql" is the statement to be compiled, encoded
+** The second argument, "zSql", is the statement to be compiled, encoded
 ** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
-** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
-** use UTF-16. {END}
-**
-** If the nByte argument is less
-** than zero, then zSql is read up to the first zero terminator.
-** If nByte is non-negative, then it is the maximum number of 
-** bytes read from zSql.  When nByte is non-negative, the
-** zSql string ends at either the first '\000' or '\u0000' character or 
+** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
+** use UTF-16.
+**
+** If the nByte argument is less than zero, then zSql is read up to the
+** first zero terminator. If nByte is non-negative, then it is the maximum
+** number of  bytes read from zSql.  When nByte is non-negative, the
+** zSql string ends at either the first '\000' or '\u0000' character or
 ** the nByte-th byte, whichever comes first. If the caller knows
 ** that the supplied string is nul-terminated, then there is a small
-** performance advantage to be had by passing an nByte parameter that 
-** is equal to the number of bytes in the input string <i>including</i> 
-** the nul-terminator bytes.{END}
+** performance advantage to be gained by passing an nByte parameter that
+** is equal to the number of bytes in the input string <i>including</i>
+** the nul-terminator bytes.
 **
-** *pzTail is made to point to the first byte past the end of the
-** first SQL statement in zSql.  These routines only compiles the first
-** statement in zSql, so *pzTail is left pointing to what remains
-** uncompiled.
+** If pzTail is not NULL then *pzTail is made to point to the first byte
+** past the end of the first SQL statement in zSql.  These routines only
+** compile the first statement in zSql, so *pzTail is left pointing to
+** what remains uncompiled.
 **
 ** *ppStmt is left pointing to a compiled [prepared statement] that can be
-** executed using [sqlite3_step()].  Or if there is an error, *ppStmt is
-** set to NULL.  If the input text contains no SQL (if the input
-** is and empty string or a comment) then *ppStmt is set to NULL.
-** {U13018} The calling procedure is responsible for deleting the
-** compiled SQL statement
-** using [sqlite3_finalize()] after it has finished with it.
+** executed using [sqlite3_step()].  If there is an error, *ppStmt is set
+** to NULL.  If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
+** ppStmt may not be NULL.
 **
-** On success, [SQLITE_OK] is returned.  Otherwise an 
-** [error code] is returned.
+** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
 **
 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
 ** recommended for all new programs. The two older interfaces are retained
 ** for backwards compatibility, but their use is discouraged.
 ** In the "v2" interfaces, the prepared statement
-** that is returned (the [sqlite3_stmt] object) contains a copy of the 
-** original SQL text. {END} This causes the [sqlite3_step()] interface to
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
 ** behave a differently in two ways:
 **
 ** <ol>
@@ -2326,83 +2404,48 @@ int sqlite3_limit(sqlite3*, int id, int newVal);
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
 ** statement and try to run it again.  If the schema has changed in
 ** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, 
-** [SQLITE_SCHEMA] is now a fatal error.  Calling
-** [sqlite3_prepare_v2()] again will not make the
+** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
+** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
 ** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return. {END}
+** of the parsing error that results in an [SQLITE_SCHEMA] return.
 ** </li>
 **
 ** <li>
-** When an error occurs, 
-** [sqlite3_step()] will return one of the detailed 
-** [error codes] or [extended error codes]. 
-** The legacy behavior was that [sqlite3_step()] would only return a generic
-** [SQLITE_ERROR] result code and you would have to make a second call to
-** [sqlite3_reset()] in order to find the underlying cause of the problem.
-** With the "v2" prepare interfaces, the underlying reason for the error is
-** returned immediately.
+** When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes].  The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and you would have to make a second call to [sqlite3_reset()] in order
+** to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
 ** </li>
 ** </ol>
 **
-** INVARIANTS:
-**
-** {F13011} The [sqlite3_prepare(db,zSql,...)] and
-**          [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
-**          text in their zSql parameter as UTF-8.
+** Requirements:
+** [H13011] [H13012] [H13013] [H13014] [H13015] [H13016] [H13019] [H13021]
 **
-** {F13012} The [sqlite3_prepare16(db,zSql,...)] and
-**          [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
-**          text in their zSql parameter as UTF-16 in the native byte order.
-**
-** {F13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is less than zero, then SQL text is
-**          read from zSql is read up to the first zero terminator.
-**
-** {F13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is non-negative, then at most nBytes bytes
-**          SQL text is read from zSql.
-**
-** {F13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
-**          if the zSql input text contains more than one SQL statement
-**          and pzTail is not NULL, then *pzTail is made to point to the
-**          first byte past the end of the first SQL statement in zSql.
-**          <todo>What does *pzTail point to if there is one statement?</todo>
-**
-** {F13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
-**          or one of its variants writes into *ppStmt a pointer to a new
-**          [prepared statement] or a pointer to NULL
-**          if zSql contains nothing other than whitespace or comments. 
-**
-** {F13019} The [sqlite3_prepare_v2()] interface and its variants return
-**          [SQLITE_OK] or an appropriate [error code] upon failure.
-**
-** {F13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
-**          variants returns an error (any value other than [SQLITE_OK])
-**          it first sets *ppStmt to NULL.
 */
-int sqlite3_prepare(
+SQLITE_API int sqlite3_prepare(
   sqlite3 *db,            /* Database handle */
   const char *zSql,       /* SQL statement, UTF-8 encoded */
   int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
-int sqlite3_prepare_v2(
+SQLITE_API int sqlite3_prepare_v2(
   sqlite3 *db,            /* Database handle */
   const char *zSql,       /* SQL statement, UTF-8 encoded */
   int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
-int sqlite3_prepare16(
+SQLITE_API int sqlite3_prepare16(
   sqlite3 *db,            /* Database handle */
   const void *zSql,       /* SQL statement, UTF-16 encoded */
   int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
-int sqlite3_prepare16_v2(
+SQLITE_API int sqlite3_prepare16_v2(
   sqlite3 *db,            /* Database handle */
   const void *zSql,       /* SQL statement, UTF-16 encoded */
   int nByte,              /* Maximum length of zSql in bytes. */
@@ -2411,85 +2454,78 @@ int sqlite3_prepare16_v2(
 );
 
 /*
-** CAPIREF: Retrieving Statement SQL {F13100}
-**
-** This intereface can be used to retrieve a saved copy of the original
-** SQL text used to create a [prepared statement].
-**
-** INVARIANTS:
+** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
 **
-** {F13101} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare_v2()] or
-**          [sqlite3_prepare16_v2()],
-**          then [sqlite3_sql()] function returns a pointer to a
-**          zero-terminated string containing a UTF-8 rendering
-**          of the original SQL statement.
+** This interface can be used to retrieve a saved copy of the original
+** SQL text used to create a [prepared statement] if that statement was
+** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
 **
-** {F13102} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare()] or
-**          [sqlite3_prepare16()],
-**          then [sqlite3_sql()] function returns a NULL pointer.
-**
-** {F13103} The string returned by [sqlite3_sql(S)] is valid until the
-**          [prepared statement] S is deleted using [sqlite3_finalize(S)].
+** Requirements:
+** [H13101] [H13102] [H13103]
 */
-const char *sqlite3_sql(sqlite3_stmt *pStmt);
+SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF:  Dynamically Typed Value Object  {F15000}
+** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
 **
 ** SQLite uses the sqlite3_value object to represent all values
-** that can be stored in a database table.
-** SQLite uses dynamic typing for the values it stores.  
-** Values stored in sqlite3_value objects can be
-** be integers, floating point values, strings, BLOBs, or NULL.
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores. Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
 **
 ** An sqlite3_value object may be either "protected" or "unprotected".
 ** Some interfaces require a protected sqlite3_value.  Other interfaces
 ** will accept either a protected or an unprotected sqlite3_value.
-** Every interface that accepts sqlite3_value arguments specifies 
+** Every interface that accepts sqlite3_value arguments specifies
 ** whether or not it requires a protected sqlite3_value.
 **
 ** The terms "protected" and "unprotected" refer to whether or not
 ** a mutex is held.  A internal mutex is held for a protected
 ** sqlite3_value object but no mutex is held for an unprotected
 ** sqlite3_value object.  If SQLite is compiled to be single-threaded
-** (with SQLITE_THREADSAFE=0 and with [sqlite3_threadsafe()] returning 0)
-** then there is no distinction between
-** protected and unprotected sqlite3_value objects and they can be
-** used interchangable.  However, for maximum code portability it
-** is recommended that applications make the distinction between
-** between protected and unprotected sqlite3_value objects even if
-** they are single threaded.
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes 
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably.  However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between between protected and unprotected
+** sqlite3_value objects even when not strictly required.
 **
 ** The sqlite3_value objects that are passed as parameters into the
-** implementation of application-defined SQL functions are protected.
+** implementation of [application-defined SQL functions] are protected.
 ** The sqlite3_value object returned by
 ** [sqlite3_column_value()] is unprotected.
 ** Unprotected sqlite3_value objects may only be used with
-** [sqlite3_result_value()] and [sqlite3_bind_value()].  All other
-** interfaces that use sqlite3_value require protected sqlite3_value objects.
+** [sqlite3_result_value()] and [sqlite3_bind_value()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
 */
 typedef struct Mem sqlite3_value;
 
 /*
-** CAPI3REF:  SQL Function Context Object {F16001}
+** CAPI3REF: SQL Function Context Object {H16001} <S20200>
 **
 ** The context in which an SQL function executes is stored in an
-** sqlite3_context object.  A pointer to an sqlite3_context
-** object is always first parameter to application-defined SQL functions.
+** sqlite3_context object.  A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
 */
 typedef struct sqlite3_context sqlite3_context;
 
 /*
-** CAPI3REF:  Binding Values To Prepared Statements {F13500}
+** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
 **
-** In the SQL strings input to [sqlite3_prepare_v2()] and its
-** variants, literals may be replace by a parameter in one
-** of these forms:
+** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a [parameter] that matches one of following
+** templates:
 **
 ** <ul>
 ** <li>  ?
@@ -2499,33 +2535,32 @@ typedef struct sqlite3_context sqlite3_context;
 ** <li>  $VVV
 ** </ul>
 **
-** In the parameter forms shown above NNN is an integer literal,
-** VVV alpha-numeric parameter name.
-** The values of these parameters (also called "host parameter names"
-** or "SQL parameters")
+** In the templates above, NNN represents an integer literal,
+** and VVV represents an alphanumeric identifer.  The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
-** The first argument to the sqlite3_bind_*() routines always
-** is a pointer to the [sqlite3_stmt] object returned from
-** [sqlite3_prepare_v2()] or its variants. The second
-** argument is the index of the parameter to be set. The
-** first parameter has an index of 1.  When the same named
-** parameter is used more than once, second and subsequent
-** occurrences have the same index as the first occurrence. 
+** The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** The second argument is the index of the SQL parameter to be set.
+** The leftmost SQL parameter has an index of 1.  When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
 ** The index for named parameters can be looked up using the
-** [sqlite3_bind_parameter_name()] API if desired.  The index
+** [sqlite3_bind_parameter_index()] API if desired.  The index
 ** for "?NNN" parameters is the value of NNN.
-** The NNN value must be between 1 and the compile-time
-** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999).
+** The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
 **
 ** The third argument is the value to bind to the parameter.
 **
-** In those
-** routines that have a fourth argument, its value is the number of bytes
-** in the parameter.  To be clear: the value is the number of <u>bytes</u>
-** in the value, not the number of characters. 
+** In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter.  To be clear: the value is the
+** number of <u>bytes</u> in the value, not the number of characters.
 ** If the fourth parameter is negative, the length of the string is
-** number of bytes up to the first zero terminator.
+** the number of bytes up to the first zero terminator.
 **
 ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
@@ -2537,12 +2572,12 @@ typedef struct sqlite3_context sqlite3_context;
 ** the sqlite3_bind_*() routine returns.
 **
 ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
-** is filled with zeros.  A zeroblob uses a fixed amount of memory
-** (just an integer to hold it size) while it is being processed.
-** Zeroblobs are intended to serve as place-holders for BLOBs whose
-** content is later written using 
-** [sqlite3_blob_open | increment BLOB I/O] routines. A negative
-** value for the zeroblob results in a zero-length BLOB.
+** is filled with zeroes.  A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** A negative value for the zeroblob results in a zero-length BLOB.
 **
 ** The sqlite3_bind_*() routines must be called after
 ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
@@ -2552,7 +2587,7 @@ typedef struct sqlite3_context sqlite3_context;
 **
 ** These routines return [SQLITE_OK] on success or an error code if
 ** anything goes wrong.  [SQLITE_RANGE] is returned if the parameter
-** index is out of range.  [SQLITE_NOMEM] is returned if malloc fails.
+** index is out of range.  [SQLITE_NOMEM] is returned if malloc() fails.
 ** [SQLITE_MISUSE] might be returned if these routines are called on a
 ** virtual machine that is the wrong state or which has already been finalized.
 ** Detection of misuse is unreliable.  Applications should not depend
@@ -2561,136 +2596,64 @@ typedef struct sqlite3_context sqlite3_context;
 ** panic rather than return SQLITE_MISUSE.
 **
 ** See also: [sqlite3_bind_parameter_count()],
-** [sqlite3_bind_parameter_name()], and
-** [sqlite3_bind_parameter_index()].
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13506} The [sqlite3_prepare | SQL statement compiler] recognizes
-**          tokens of the forms "?", "?NNN", "$VVV", ":VVV", and "@VVV"
-**          as SQL parameters, where NNN is any sequence of one or more
-**          digits and where VVV is any sequence of one or more 
-**          alphanumeric characters or "::" optionally followed by
-**          a string containing no spaces and contained within parentheses.
-**
-** {F13509} The initial value of an SQL parameter is NULL.
-**
-** {F13512} The index of an "?" SQL parameter is one larger than the
-**          largest index of SQL parameter to the left, or 1 if
-**          the "?" is the leftmost SQL parameter.
-**
-** {F13515} The index of an "?NNN" SQL parameter is the integer NNN.
-**
-** {F13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
-**          the same as the index of leftmost occurances of the same
-**          parameter, or one more than the largest index over all
-**          parameters to the left if this is the first occurrance
-**          of this parameter, or 1 if this is the leftmost parameter.
-**
-** {F13521} The [sqlite3_prepare | SQL statement compiler] fail with
-**          an [SQLITE_RANGE] error if the index of an SQL parameter
-**          is less than 1 or greater than SQLITE_MAX_VARIABLE_NUMBER.
-**
-** {F13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
-**          associate the value V with all SQL parameters having an
-**          index of N in the [prepared statement] S.
-**
-** {F13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
-**          override prior calls with the same values of S and N.
-**
-** {F13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
-**          persist across calls to [sqlite3_reset(S)].
-**
-** {F13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
-**          bytes of the blob or string pointed to by V, when L
-**          is non-negative.
-**
-** {F13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
-**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
-**          from V through the first zero character when L is negative.
-**
-** {F13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
-**          constant [SQLITE_STATIC], SQLite assumes that the value V
-**          is held in static unmanaged space that will not change
-**          during the lifetime of the binding.
-**
-** {F13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
-**          constant [SQLITE_TRANSIENT], the routine makes a 
-**          private copy of V value before it returns.
-**
-** {F13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
-**          [sqlite3_bind_text(S,N,V,L,D)], or
-**          [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
-**          a function, SQLite invokes that function to destroy the
-**          V value after it has finished using the V value.
-**
-** {F13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
-**          is a blob of L bytes, or a zero-length blob if L is negative.
-**
-** {F13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
-**          be either a [protected sqlite3_value] object or an
-**          [unprotected sqlite3_value] object.
-*/
-int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
-int sqlite3_bind_double(sqlite3_stmt*, int, double);
-int sqlite3_bind_int(sqlite3_stmt*, int, int);
-int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
-int sqlite3_bind_null(sqlite3_stmt*, int);
-int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
-int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
-int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
-int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
-
-/*
-** CAPI3REF: Number Of SQL Parameters {F13600}
-**
-** This routine can be used to find the number of SQL parameters
-** in a prepared statement.  SQL parameters are tokens of the
-** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
-** place-holders for values that are [sqlite3_bind_blob | bound]
-** to the parameters at a later time.
+** Requirements:
+** [H13506] [H13509] [H13512] [H13515] [H13518] [H13521] [H13524] [H13527]
+** [H13530] [H13533] [H13536] [H13539] [H13542] [H13545] [H13548] [H13551]
 **
-** This routine actually returns the index of the largest parameter.
-** For all forms except ?NNN, this will correspond to the number of
-** unique parameters.  If parameters of the ?NNN are used, there may
-** be gaps in the list.
-**
-** See also: [sqlite3_bind_blob|sqlite3_bind()],
+*/
+SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
+SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
+SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
+SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
+SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
+SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
+SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
+
+/*
+** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
+**
+** This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement].  SQL parameters are tokens of the
+** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
+** placeholders for values that are [sqlite3_bind_blob | bound]
+** to the parameters at a later time.
+**
+** This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters.  If parameters of the ?NNN are used,
+** there may be gaps in the list.
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
 ** [sqlite3_bind_parameter_name()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13601} The [sqlite3_bind_parameter_count(S)] interface returns
-**          the largest index of all SQL parameters in the
-**          [prepared statement] S, or 0 if S
-**          contains no SQL parameters.
+** Requirements:
+** [H13601]
 */
-int sqlite3_bind_parameter_count(sqlite3_stmt*);
+SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Name Of A Host Parameter {F13620}
+** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
 **
 ** This routine returns a pointer to the name of the n-th
-** SQL parameter in a [prepared statement].
+** [SQL parameter] in a [prepared statement].
 ** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
 ** respectively.
 ** In other words, the initial ":" or "$" or "@" or "?"
 ** is included as part of the name.
-** Parameters of the form "?" without a following integer have no name.
+** Parameters of the form "?" without a following integer have no name
+** and are also referred to as "anonymous parameters".
 **
 ** The first host parameter has an index of 1, not 0.
 **
 ** If the value n is out of range or if the n-th parameter is
 ** nameless, then NULL is returned.  The returned string is
-** always in the UTF-8 encoding even if the named parameter was
+** always in UTF-8 encoding even if the named parameter was
 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
 ** [sqlite3_prepare16_v2()].
 **
@@ -2698,18 +2661,13 @@ int sqlite3_bind_parameter_count(sqlite3_stmt*);
 ** [sqlite3_bind_parameter_count()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
-**          a UTF-8 rendering of the name of the SQL parameter in
-**          [prepared statement] S having index N, or
-**          NULL if there is no SQL parameter with index N or if the
-**          parameter with index N is an anonymous parameter "?".
+** Requirements:
+** [H13621]
 */
-const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
+SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 
 /*
-** CAPI3REF: Index Of A Parameter With A Given Name {F13640}
+** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
 **
 ** Return the index of an SQL parameter given its name.  The
 ** index value returned is suitable for use as the second
@@ -2722,64 +2680,49 @@ const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 ** [sqlite3_bind_parameter_count()], and
 ** [sqlite3_bind_parameter_index()].
 **
-** INVARIANTS:
-**
-** {F13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
-**          the index of SQL parameter in [prepared statement]
-**          S whose name matches the UTF-8 string N, or 0 if there is
-**          no match.
+** Requirements:
+** [H13641]
 */
-int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
+SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
 
 /*
-** CAPI3REF: Reset All Bindings On A Prepared Statement {F13660}
+** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
 **
-** Contrary to the intuition of many, [sqlite3_reset()] does not
-** reset the [sqlite3_bind_blob | bindings] on a 
-** [prepared statement].  Use this routine to
-** reset all host parameters to NULL.
+** Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** Use this routine to reset all host parameters to NULL.
 **
-** INVARIANTS:
-**
-** {F13661} The [sqlite3_clear_bindings(S)] interface resets all
-**          SQL parameter bindings in [prepared statement] S
-**          back to NULL.
+** Requirements:
+** [H13661]
 */
-int sqlite3_clear_bindings(sqlite3_stmt*);
+SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number Of Columns In A Result Set {F13710}
-**
-** Return the number of columns in the result set returned by the 
-** [prepared statement]. This routine returns 0
-** if pStmt is an SQL statement that does not return data (for 
-** example an UPDATE).
+** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
 **
-** INVARIANTS:
+** Return the number of columns in the result set returned by the
+** [prepared statement]. This routine returns 0 if pStmt is an SQL
+** statement that does not return data (for example an [UPDATE]).
 **
-** {F13711} The [sqlite3_column_count(S)] interface returns the number of
-**          columns in the result set generated by the
-**          [prepared statement] S, or 0 if S does not generate
-**          a result set.
+** Requirements:
+** [H13711]
 */
-int sqlite3_column_count(sqlite3_stmt *pStmt);
+SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Column Names In A Result Set {F13720}
+** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
 **
 ** These routines return the name assigned to a particular column
-** in the result set of a SELECT statement.  The sqlite3_column_name()
-** interface returns a pointer to a zero-terminated UTF8 string
+** in the result set of a [SELECT] statement.  The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
-** UTF16 string.  The first parameter is the
-** [prepared statement] that implements the SELECT statement.
-** The second parameter is the column number.  The left-most column is
-** number 0.
+** UTF-16 string.  The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. The second parameter is the
+** column number.  The leftmost column is number 0.
 **
-** The returned string pointer is valid until either the 
-** [prepared statement] is destroyed by [sqlite3_finalize()]
-** or until the next call sqlite3_column_name() or sqlite3_column_name16()
-** on the same column.
+** The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
 **
 ** If sqlite3_malloc() fails during the processing of either routine
 ** (for example during a conversion from UTF-8 to UTF-16) then a
@@ -2790,168 +2733,85 @@ int sqlite3_column_count(sqlite3_stmt *pStmt);
 ** then the name of the column is unspecified and may change from
 ** one release of SQLite to the next.
 **
-** INVARIANTS:
-**
-** {F13721} A successful invocation of the [sqlite3_column_name(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-8 string.
-**
-** {F13723} A successful invocation of the [sqlite3_column_name16(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-16 string in the native byte order.
-**
-** {F13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
-**          interfaces return a NULL pointer if they are unable to
-**          allocate memory memory to hold there normal return strings.
-**
-** {F13725} If the N parameter to [sqlite3_column_name(S,N)] or
-**          [sqlite3_column_name16(S,N)] is out of range, then the
-**          interfaces returns a NULL pointer.
-** 
-** {F13726} The strings returned by [sqlite3_column_name(S,N)] and
-**          [sqlite3_column_name16(S,N)] are valid until the next
-**          call to either routine with the same S and N parameters
-**          or until [sqlite3_finalize(S)] is called.
-**
-** {F13727} When a result column of a [SELECT] statement contains
-**          an AS clause, the name of that column is the indentifier
-**          to the right of the AS keyword.
+** Requirements:
+** [H13721] [H13723] [H13724] [H13725] [H13726] [H13727]
 */
-const char *sqlite3_column_name(sqlite3_stmt*, int N);
-const void *sqlite3_column_name16(sqlite3_stmt*, int N);
+SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
+SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
 
 /*
-** CAPI3REF: Source Of Data In A Query Result {F13740}
+** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
 **
 ** These routines provide a means to determine what column of what
-** table in which database a result of a SELECT statement comes from.
+** table in which database a result of a [SELECT] statement comes from.
 ** The name of the database or table or column can be returned as
-** either a UTF8 or UTF16 string.  The _database_ routines return
+** either a UTF-8 or UTF-16 string.  The _database_ routines return
 ** the database name, the _table_ routines return the table name, and
 ** the origin_ routines return the column name.
-** The returned string is valid until
-** the [prepared statement] is destroyed using
-** [sqlite3_finalize()] or until the same information is requested
+** The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the same information is requested
 ** again in a different encoding.
 **
 ** The names returned are the original un-aliased names of the
 ** database, table, and column.
 **
 ** The first argument to the following calls is a [prepared statement].
-** These functions return information about the Nth column returned by 
+** These functions return information about the Nth column returned by
 ** the statement, where N is the second function argument.
 **
-** If the Nth column returned by the statement is an expression
-** or subquery and is not a column value, then all of these functions
-** return NULL.  These routine might also return NULL if a memory
-** allocation error occurs.  Otherwise, they return the 
-** name of the attached database, table and column that query result
-** column was extracted from.
+** If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL.  These routine might also return NULL if a memory allocation error
+** occurs.  Otherwise, they return the name of the attached database, table
+** and column that query result column was extracted from.
 **
 ** As with all other SQLite APIs, those postfixed with "16" return
 ** UTF-16 encoded strings, the other functions return UTF-8. {END}
 **
-** These APIs are only available if the library was compiled with the 
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 **
-** {U13751}
+** {A13751}
 ** If two or more threads call one or more of these routines against the same
 ** prepared statement and column at the same time then the results are
 ** undefined.
 **
-** INVARIANTS:
-**
-** {F13741} The [sqlite3_column_database_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13742} The [sqlite3_column_database_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13743} The [sqlite3_column_table_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13744} The [sqlite3_column_table_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13745} The [sqlite3_column_origin_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13748} The return values from
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          are valid
-**          for the lifetime of the [prepared statement]
-**          or until the encoding is changed by another metadata
-**          interface call for the same prepared statement and column.
-**
-** LIMITATIONS:
-**
-** {U13751} If two or more threads call one or more
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          the same [prepared statement] and result column
-**          at the same time then the results are undefined.
-*/
-const char *sqlite3_column_database_name(sqlite3_stmt*,int);
-const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
-const char *sqlite3_column_table_name(sqlite3_stmt*,int);
-const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
-const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
-const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
-
-/*
-** CAPI3REF: Declared Datatype Of A Query Result {F13760}
-**
-** The first parameter is a [prepared statement]. 
-** If this statement is a SELECT statement and the Nth column of the 
-** returned result set of that SELECT is a table column (not an
+** Requirements:
+** [H13741] [H13742] [H13743] [H13744] [H13745] [H13746] [H13748]
+**
+** If two or more threads call one or more
+** [sqlite3_column_database_name | column metadata interfaces]
+** for the same [prepared statement] and result column
+** at the same time then the results are undefined.
+*/
+SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
+**
+** The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
 ** expression or subquery) then the declared type of the table
 ** column is returned.  If the Nth column of the result set is an
 ** expression or subquery, then a NULL pointer is returned.
-** The returned string is always UTF-8 encoded.  {END} 
-** For example, in the database schema:
+** The returned string is always UTF-8 encoded. {END}
+**
+** For example, given the database schema:
 **
 ** CREATE TABLE t1(c1 VARIANT);
 **
-** And the following statement compiled:
+** and the following statement to be compiled:
 **
 ** SELECT c1 + 1, c1 FROM t1;
 **
-** Then this routine would return the string "VARIANT" for the second
-** result column (i==1), and a NULL pointer for the first result column
-** (i==0).
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).
 **
 ** SQLite uses dynamic run-time typing.  So just because a column
 ** is declared to contain a particular type does not mean that the
@@ -2960,57 +2820,36 @@ const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 ** is associated with individual values, not with the containers
 ** used to hold those values.
 **
-** INVARIANTS:
-**
-** {F13761}  A successful call to [sqlite3_column_decltype(S,N)]
-**           returns a zero-terminated UTF-8 string containing the
-**           the declared datatype of the table column that appears
-**           as the Nth column (numbered from 0) of the result set to the
-**           [prepared statement] S.
-**
-** {F13762}  A successful call to [sqlite3_column_decltype16(S,N)]
-**           returns a zero-terminated UTF-16 native byte order string
-**           containing the declared datatype of the table column that appears
-**           as the Nth column (numbered from 0) of the result set to the
-**           [prepared statement] S.
-**
-** {F13763}  If N is less than 0 or N is greater than or equal to
-**           the number of columns in [prepared statement] S
-**           or if the Nth column of S is an expression or subquery rather
-**           than a table column or if a memory allocation failure
-**           occurs during encoding conversions, then
-**           calls to [sqlite3_column_decltype(S,N)] or
-**           [sqlite3_column_decltype16(S,N)] return NULL.
-*/
-const char *sqlite3_column_decltype(sqlite3_stmt*,int);
-const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
-
-/* 
-** CAPI3REF:  Evaluate An SQL Statement {F13200}
-**
-** After an [prepared statement] has been prepared with a call
-** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of
-** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()],
-** then this function must be called one or more times to evaluate the 
-** statement.
-**
-** The details of the behavior of this sqlite3_step() interface depend
+** Requirements:
+** [H13761] [H13762] [H13763]
+*/
+SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
+**
+** After a [prepared statement] has been prepared using either
+** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
+**
+** The details of the behavior of the sqlite3_step() interface depend
 ** on whether the statement was prepared using the newer "v2" interface
 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
 ** new "v2" interface is recommended for new applications but the legacy
 ** interface will continue to be supported.
 **
-** In the legacy interface, the return value will be either [SQLITE_BUSY], 
+** In the legacy interface, the return value will be either [SQLITE_BUSY],
 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
-** With the "v2" interface, any of the other [SQLITE_OK | result code]
-** or [SQLITE_IOERR_READ | extended result code] might be returned as
-** well.
+** With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
 **
 ** [SQLITE_BUSY] means that the database engine was unable to acquire the
-** database locks it needs to do its job.  If the statement is a COMMIT
+** database locks it needs to do its job.  If the statement is a [COMMIT]
 ** or occurs outside of an explicit transaction, then you can retry the
-** statement.  If the statement is not a COMMIT and occurs within a
+** statement.  If the statement is not a [COMMIT] and occurs within a
 ** explicit transaction then you should rollback the transaction before
 ** continuing.
 **
@@ -3019,16 +2858,15 @@ const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 ** machine without first calling [sqlite3_reset()] to reset the virtual
 ** machine back to its initial state.
 **
-** If the SQL statement being executed returns any data, then 
-** [SQLITE_ROW] is returned each time a new row of data is ready
-** for processing by the caller. The values may be accessed using
-** the [sqlite3_column_int | column access functions].
+** If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
 ** sqlite3_step() is called again to retrieve the next row of data.
-** 
+**
 ** [SQLITE_ERROR] means that a run-time error (such as a constraint
 ** violation) has occurred.  sqlite3_step() should not be called again on
 ** the VM. More information may be found by calling [sqlite3_errmsg()].
-** With the legacy interface, a more specific error code (example:
+** With the legacy interface, a more specific error code (for example,
 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
 ** can be obtained by calling [sqlite3_reset()] on the
 ** [prepared statement].  In the "v2" interface,
@@ -3036,80 +2874,43 @@ const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 **
 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
 ** Perhaps it was called on a [prepared statement] that has
-** already been [sqlite3_finalize | finalized] or on one that had 
+** already been [sqlite3_finalize | finalized] or on one that had
 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
 ** be the case that the same database connection is being used by two or
 ** more threads at the same moment in time.
 **
-** <b>Goofy Interface Alert:</b>
-** In the legacy interface, 
-** the sqlite3_step() API always returns a generic error code,
-** [SQLITE_ERROR], following any error other than [SQLITE_BUSY]
-** and [SQLITE_MISUSE].  You must call [sqlite3_reset()] or
-** [sqlite3_finalize()] in order to find one of the specific
-** [error codes] that better describes the error.
+** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
 ** We admit that this is a goofy design.  The problem has been fixed
 ** with the "v2" interface.  If you prepare all of your SQL statements
 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
-** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the 
-** more specific [error codes] are returned directly
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
 ** by sqlite3_step().  The use of the "v2" interface is recommended.
 **
-** INVARIANTS:
-**
-** {F13202}  If [prepared statement] S is ready to be
-**           run, then [sqlite3_step(S)] advances that prepared statement
-**           until to completion or until it is ready to return another
-**           row of the result set or an interrupt or run-time error occurs.
-**
-** {F15304}  When a call to [sqlite3_step(S)] causes the 
-**           [prepared statement] S to run to completion,
-**           the function returns [SQLITE_DONE].
-**
-** {F15306}  When a call to [sqlite3_step(S)] stops because it is ready
-**           to return another row of the result set, it returns
-**           [SQLITE_ROW].
-**
-** {F15308}  If a call to [sqlite3_step(S)] encounters an
-**           [sqlite3_interrupt|interrupt] or a run-time error,
-**           it returns an appropraite error code that is not one of
-**           [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
-**
-** {F15310}  If an [sqlite3_interrupt|interrupt] or run-time error
-**           occurs during a call to [sqlite3_step(S)]
-**           for a [prepared statement] S created using
-**           legacy interfaces [sqlite3_prepare()] or
-**           [sqlite3_prepare16()] then the function returns either
-**           [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
+** Requirements:
+** [H13202] [H15304] [H15306] [H15308] [H15310]
 */
-int sqlite3_step(sqlite3_stmt*);
+SQLITE_API int sqlite3_step(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number of columns in a result set {F13770}
-**
-** Return the number of values in the current row of the result set.
-**
-** INVARIANTS:
+** CAPI3REF: Number of columns in a result set {H13770} <S10700>
 **
-** {F13771}  After a call to [sqlite3_step(S)] that returns
-**           [SQLITE_ROW], the [sqlite3_data_count(S)] routine
-**           will return the same value as the
-**           [sqlite3_column_count(S)] function.
+** Returns the number of values in the current row of the result set.
 **
-** {F13772}  After [sqlite3_step(S)] has returned any value other than
-**           [SQLITE_ROW] or before [sqlite3_step(S)] has been 
-**           called on the [prepared statement] for
-**           the first time since it was [sqlite3_prepare|prepared]
-**           or [sqlite3_reset|reset], the [sqlite3_data_count(S)]
-**           routine returns zero.
+** Requirements:
+** [H13771] [H13772]
 */
-int sqlite3_data_count(sqlite3_stmt *pStmt);
+SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Fundamental Datatypes {F10265}
+** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
 ** KEYWORDS: SQLITE_TEXT
 **
-** {F10266}Every value in SQLite has one of five fundamental datatypes:
+** {H10266} Every value in SQLite has one of five fundamental datatypes:
 **
 ** <ul>
 ** <li> 64-bit signed integer
@@ -3123,7 +2924,7 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
 ** for a completely different meaning.  Software that links against both
-** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
 ** SQLITE_TEXT.
 */
 #define SQLITE_INTEGER  1
@@ -3138,33 +2939,31 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 #define SQLITE3_TEXT     3
 
 /*
-** CAPI3REF: Results Values From A Query {F13800}
+** CAPI3REF: Result Values From A Query {H13800} <S10700>
+** KEYWORDS: {column access functions}
 **
 ** These routines form the "result set query" interface.
 **
-** These routines return information about
-** a single column of the current result row of a query.  In every
-** case the first argument is a pointer to the 
-** [prepared statement] that is being
-** evaluated (the [sqlite3_stmt*] that was returned from 
-** [sqlite3_prepare_v2()] or one of its variants) and
-** the second argument is the index of the column for which information 
-** should be returned.  The left-most column of the result set
-** has an index of 0.
-**
-** If the SQL statement is not currently point to a valid row, or if the
-** the column index is out of range, the result is undefined. 
+** These routines return information about a single column of the current
+** result row of a query.  In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned.  The leftmost column of the result set has the index 0.
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
 ** These routines may only be called when the most recent call to
 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
-** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently.
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
 ** If any of these routines are called after [sqlite3_reset()] or
 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
 ** something other than [SQLITE_ROW], the results are undefined.
 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
 ** are called from a different thread while any of these routines
-** are pending, then the results are undefined.  
+** are pending, then the results are undefined.
 **
-** The sqlite3_column_type() routine returns 
+** The sqlite3_column_type() routine returns the
 ** [SQLITE_INTEGER | datatype code] for the initial data type
 ** of the result column.  The returned value is one of [SQLITE_INTEGER],
 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
@@ -3174,7 +2973,7 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** versions of SQLite may change the behavior of sqlite3_column_type()
 ** following a type conversion.
 **
-** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 
+** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
 ** routine returns the number of bytes in that BLOB or string.
 ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
 ** the string to UTF-8 and then returns the number of bytes.
@@ -3187,11 +2986,11 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  The return
-** value from sqlite3_column_blob() for a zero-length blob is an arbitrary
+** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
 ** pointer, possibly even a NULL pointer.
 **
 ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.  
+** but leaves the result in UTF-16 in native byte order instead of UTF-8.
 ** The zero terminator is not included in this count.
 **
 ** The object returned by [sqlite3_column_value()] is an
@@ -3199,15 +2998,14 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
 ** If the [unprotected sqlite3_value] object returned by
 ** [sqlite3_column_value()] is used in any other way, including calls
-** to routines like 
-** [sqlite3_value_int()], [sqlite3_value_text()], or [sqlite3_value_bytes()],
-** then the behavior is undefined.
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], then the behavior is undefined.
 **
 ** These routines attempt to convert the value where appropriate.  For
 ** example, if the internal representation is FLOAT and a text result
-** is requested, [sqlite3_snprintf()] is used internally to do the conversion
-** automatically.  The following table details the conversions that
-** are applied:
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically.  The following table details the conversions
+** that are applied:
 **
 ** <blockquote>
 ** <table border="1">
@@ -3219,7 +3017,7 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** <tr><td>  NULL    <td>   BLOB    <td> Result is NULL pointer
 ** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
 ** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
-** <tr><td> INTEGER  <td>   BLOB    <td> Same as for INTEGER->TEXT
+** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
 ** <tr><td>  FLOAT   <td> INTEGER   <td> Convert from float to integer
 ** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
 ** <tr><td>  FLOAT   <td>   BLOB    <td> Same as FLOAT->TEXT
@@ -3234,57 +3032,56 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** The table above makes reference to standard C library functions atoi()
 ** and atof().  SQLite does not really use these functions.  It has its
-** on equavalent internal routines.  The atoi() and atof() names are
+** own equivalent internal routines.  The atoi() and atof() names are
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
 ** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
-** sqlite3_column_text16() may be invalidated. 
+** sqlite3_column_text16() may be invalidated.
 ** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** <ul>
-** <li><p>  The initial content is a BLOB and sqlite3_column_text() 
-**          or sqlite3_column_text16() is called.  A zero-terminator might
-**          need to be added to the string.</p></li>
-**
-** <li><p>  The initial content is UTF-8 text and sqlite3_column_bytes16() or
-**          sqlite3_column_text16() is called.  The content must be converted
-**          to UTF-16.</p></li>
-**
-** <li><p>  The initial content is UTF-16 text and sqlite3_column_bytes() or
-**          sqlite3_column_text() is called.  The content must be converted
-**          to UTF-8.</p></li>
+** <li> The initial content is a BLOB and sqlite3_column_text() or
+**      sqlite3_column_text16() is called.  A zero-terminator might
+**      need to be added to the string.</li>
+** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
+**      sqlite3_column_text16() is called.  The content must be converted
+**      to UTF-16.</li>
+** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
+**      sqlite3_column_text() is called.  The content must be converted
+**      to UTF-8.</li>
 ** </ul>
 **
 ** Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
 ** that the prior pointer points to will have been modified.  Other kinds
-** of conversion are done in place when it is possible, but sometime it is
-** not possible and in those cases prior pointers are invalidated.  
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
 **
 ** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
-**  <ul>
+** <ul>
 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
-**  </ul>
+** </ul>
 **
-** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(),
-** or sqlite3_column_text16() first to force the result into the desired
-** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to
-** find the size of the result.  Do not mix call to sqlite3_column_text() or
-** sqlite3_column_blob() with calls to sqlite3_column_bytes16().  And do not
-** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes().
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
 **
 ** The pointers returned are valid until a type conversion occurs as
 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
 ** [sqlite3_finalize()] is called.  The memory space used to hold strings
-** and blobs is freed automatically.  Do <b>not</b> pass the pointers returned
-** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 
+** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
+** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
 ** [sqlite3_free()].
 **
 ** If a memory allocation error occurs during the evaluation of any
@@ -3293,255 +3090,153 @@ int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** pointer.  Subsequent calls to [sqlite3_errcode()] will return
 ** [SQLITE_NOMEM].
 **
-** INVARIANTS:
-**
-** {F13803} The [sqlite3_column_blob(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a blob and then returns a
-**          pointer to the converted value.
-**
-** {F13806} The [sqlite3_column_bytes(S,N)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_column_blob(S,N)] or
-**          [sqlite3_column_text(S,N)].
-**
-** {F13809} The [sqlite3_column_bytes16(S,N)] interface returns the
-**          number of bytes in the string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_column_text16(S,N)].
-**
-** {F13812} The [sqlite3_column_double(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a floating point value and
-**          returns a copy of that value.
-**
-** {F13815} The [sqlite3_column_int(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a 64-bit signed integer and
-**          returns the lower 32 bits of that integer.
-**
-** {F13818} The [sqlite3_column_int64(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a 64-bit signed integer and
-**          returns a copy of that integer.
-**
-** {F13821} The [sqlite3_column_text(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a zero-terminated UTF-8 
-**          string and returns a pointer to that string.
-**
-** {F13824} The [sqlite3_column_text16(S,N)] interface converts the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S into a zero-terminated 2-byte
-**          aligned UTF-16 native byte order
-**          string and returns a pointer to that string.
-**
-** {F13827} The [sqlite3_column_type(S,N)] interface returns
-**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
-**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
-**          the Nth column in the current row of the result set for
-**          [prepared statement] S.
-**
-** {F13830} The [sqlite3_column_value(S,N)] interface returns a
-**          pointer to an [unprotected sqlite3_value] object for the
-**          Nth column in the current row of the result set for
-**          [prepared statement] S.
-*/
-const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
-int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
-int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
-double sqlite3_column_double(sqlite3_stmt*, int iCol);
-int sqlite3_column_int(sqlite3_stmt*, int iCol);
-sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
-const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
-const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
-int sqlite3_column_type(sqlite3_stmt*, int iCol);
-sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
-
-/*
-** CAPI3REF: Destroy A Prepared Statement Object {F13300}
-**
-** The sqlite3_finalize() function is called to delete a 
-** [prepared statement]. If the statement was
-** executed successfully, or not executed at all, then SQLITE_OK is returned.
-** If execution of the statement failed then an 
-** [error code] or [extended error code]
-** is returned. 
+** Requirements:
+** [H13803] [H13806] [H13809] [H13812] [H13815] [H13818] [H13821] [H13824]
+** [H13827] [H13830]
+*/
+SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
+SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
+SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
+SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
+
+/*
+** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
+**
+** The sqlite3_finalize() function is called to delete a [prepared statement].
+** If the statement was executed successfully or not executed at all, then
+** SQLITE_OK is returned. If execution of the statement failed then an
+** [error code] or [extended error code] is returned.
 **
 ** This routine can be called at any point during the execution of the
-** [prepared statement].  If the virtual machine has not 
+** [prepared statement].  If the virtual machine has not
 ** completed execution when this routine is called, that is like
-** encountering an error or an interrupt.  (See [sqlite3_interrupt()].) 
-** Incomplete updates may be rolled back and transactions cancelled,  
-** depending on the circumstances, and the 
+** encountering an error or an [sqlite3_interrupt | interrupt].
+** Incomplete updates may be rolled back and transactions canceled,
+** depending on the circumstances, and the
 ** [error code] returned will be [SQLITE_ABORT].
 **
-** INVARIANTS:
-**
-** {F11302} The [sqlite3_finalize(S)] interface destroys the
-**          [prepared statement] S and releases all
-**          memory and file resources held by that object.
-**
-** {F11304} If the most recent call to [sqlite3_step(S)] for the
-**          [prepared statement] S returned an error,
-**          then [sqlite3_finalize(S)] returns that same error.
+** Requirements:
+** [H11302] [H11304]
 */
-int sqlite3_finalize(sqlite3_stmt *pStmt);
+SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Reset A Prepared Statement Object {F13330}
+** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
 **
-** The sqlite3_reset() function is called to reset a 
-** [prepared statement] object.
-** back to its initial state, ready to be re-executed.
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
 ** Any SQL statement variables that had values bound to them using
 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
 ** Use [sqlite3_clear_bindings()] to reset the bindings.
 **
-** {F11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
 **          back to the beginning of its program.
 **
-** {F11334} If the most recent call to [sqlite3_step(S)] for 
+** {H11334} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
 **          or if [sqlite3_step(S)] has never before been called on S,
 **          then [sqlite3_reset(S)] returns [SQLITE_OK].
 **
-** {F11336} If the most recent call to [sqlite3_step(S)] for
+** {H11336} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S indicated an error, then
 **          [sqlite3_reset(S)] returns an appropriate [error code].
 **
-** {F11338} The [sqlite3_reset(S)] interface does not change the values
-**          of any [sqlite3_bind_blob|bindings] on [prepared statement] S.
+** {H11338} The [sqlite3_reset(S)] interface does not change the values
+**          of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
 */
-int sqlite3_reset(sqlite3_stmt *pStmt);
+SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Create Or Redefine SQL Functions {F16100}
-** KEYWORDS: {function creation routines} 
-**
-** These two functions (collectively known as
-** "function creation routines") are used to add SQL functions or aggregates
-** or to redefine the behavior of existing SQL functions or aggregates.  The
-** difference only between the two is that the second parameter, the
-** name of the (scalar) function or aggregate, is encoded in UTF-8 for
-** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
+** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
+**
+** These two functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates.  The only difference between the
+** two is that the second parameter, the name of the (scalar) function or
+** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
+** for sqlite3_create_function16().
 **
 ** The first parameter is the [database connection] to which the SQL
-** function is to be added.  If a single
-** program uses more than one [database connection] internally, then SQL
-** functions must be added individually to each [database connection].
-**
-** The second parameter is the name of the SQL function to be created
-** or redefined.
-** The length of the name is limited to 255 bytes, exclusive of the 
-** zero-terminator.  Note that the name length limit is in bytes, not
-** characters.  Any attempt to create a function with a longer name
-** will result in an SQLITE_ERROR error.
+** function is to be added.  If a single program uses more than one database
+** connection internally, then SQL functions must be added individually to
+** each database connection.
 **
-** The third parameter is the number of arguments that the SQL function or
-** aggregate takes. If this parameter is negative, then the SQL function or
-** aggregate may take any number of arguments.
+** The second parameter is the name of the SQL function to be created or
+** redefined.  The length of the name is limited to 255 bytes, exclusive of
+** the zero-terminator.  Note that the name length limit is in bytes, not
+** characters.  Any attempt to create a function with a longer name
+** will result in [SQLITE_ERROR] being returned.
+**
+** The third parameter (nArg)
+** is the number of arguments that the SQL function or
+** aggregate takes. If this parameter is -1, then the SQL function or
+** aggregate may take any number of arguments between 0 and the limit
+** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
+** parameter is less than -1 or greater than 127 then the behavior is
+** undefined.
 **
-** The fourth parameter, eTextRep, specifies what 
+** The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
 ** its parameters.  Any SQL function implementation should be able to work
 ** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
-** more efficient with one encoding than another.  It is allowed to
+** more efficient with one encoding than another.  An application may
 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
 ** times with the same function but with different values of eTextRep.
 ** When multiple implementations of the same function are available, SQLite
 ** will pick the one that involves the least amount of data conversion.
-** If there is only a single implementation which does not care what
-** text encoding is used, then the fourth argument should be
-** [SQLITE_ANY].
+** If there is only a single implementation which does not care what text
+** encoding is used, then the fourth argument should be [SQLITE_ANY].
 **
-** The fifth parameter is an arbitrary pointer.  The implementation
-** of the function can gain access to this pointer using
-** [sqlite3_user_data()].
+** The fifth parameter is an arbitrary pointer.  The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].
 **
 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
-** pointers to C-language functions that implement the SQL
-** function or aggregate. A scalar SQL function requires an implementation of
-** the xFunc callback only, NULL pointers should be passed as the xStep
-** and xFinal parameters. An aggregate SQL function requires an implementation
-** of xStep and xFinal and NULL should be passed for xFunc. To delete an
-** existing SQL function or aggregate, pass NULL for all three function
-** callback.
+** pointers to C-language functions that implement the SQL function or
+** aggregate. A scalar SQL function requires an implementation of the xFunc
+** callback only, NULL pointers should be passed as the xStep and xFinal
+** parameters. An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL should be passed for xFunc. To delete an existing
+** SQL function or aggregate, pass NULL for all three function callbacks.
 **
 ** It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
-** arguments or differing perferred text encodings.  SQLite will use
-** the implementation most closely matches the way in which the
-** SQL function is used.
-**
-** INVARIANTS:
-**
-** {F16103} The [sqlite3_create_function16()] interface behaves exactly
-**          like [sqlite3_create_function()] in every way except that it
-**          interprets the zFunctionName argument as
-**          zero-terminated UTF-16 native byte order instead of as a
-**          zero-terminated UTF-8.
-**
-** {F16106} A successful invocation of
-**          the [sqlite3_create_function(D,X,N,E,...)] interface registers
-**          or replaces callback functions in [database connection] D
-**          used to implement the SQL function named X with N parameters
-**          and having a perferred text encoding of E.
-**
-** {F16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          replaces the P, F, S, and L values from any prior calls with
-**          the same D, X, N, and E values.
-**
-** {F16112} The [sqlite3_create_function(D,X,...)] interface fails with
-**          a return code of [SQLITE_ERROR] if the SQL function name X is
-**          longer than 255 bytes exclusive of the zero terminator.
-**
-** {F16118} Either F must be NULL and S and L are non-NULL or else F
-**          is non-NULL and S and L are NULL, otherwise
-**          [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
-**
-** {F16121} The [sqlite3_create_function(D,...)] interface fails with an
-**          error code of [SQLITE_BUSY] if there exist [prepared statements]
-**          associated with the [database connection] D.
-**
-** {F16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
-**          error code of [SQLITE_ERROR] if parameter N (specifying the number
-**          of arguments to the SQL function being registered) is less
-**          than -1 or greater than 127.
-**
-** {F16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
-**          named X when the number of arguments to the SQL function is
-**          exactly N.
-**
-** {F16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
-**          named X with any number of arguments.
-**
-** {F16133} When calls to [sqlite3_create_function(D,X,N,...)]
-**          specify multiple implementations of the same function X
-**          and when one implementation has N>=0 and the other has N=(-1)
-**          the implementation with a non-zero N is preferred.
-**
-** {F16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
-**          specify multiple implementations of the same function X with
-**          the same number of arguments N but with different
-**          encodings E, then the implementation where E matches the
-**          database encoding is preferred.
-**
-** {F16139} For an aggregate SQL function created using
-**          [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finializer
-**          function L will always be invoked exactly once if the
-**          step function S is called one or more times.
-**
-** {F16142} When SQLite invokes either the xFunc or xStep function of
-**          an application-defined SQL function or aggregate created
-**          by [sqlite3_create_function()] or [sqlite3_create_function16()],
-**          then the array of [sqlite3_value] objects passed as the
-**          third parameter are always [protected sqlite3_value] objects.
-*/
-int sqlite3_create_function(
+** arguments or differing preferred text encodings.  SQLite will use
+** the implementation that most closely matches the way in which the
+** SQL function is used.  A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg.  A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.  
+** A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** Built-in functions may be overloaded by new application-defined functions.
+** The first application-defined function with a given name overrides all
+** built-in functions in the same [database connection] with the same name.
+** Subsequent application-defined functions of the same name only override 
+** prior application-defined functions that are an exact match for the
+** number of parameters and preferred encoding.
+**
+** An application-defined function is permitted to call other
+** SQLite interfaces.  However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
+**
+** Requirements:
+** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127]
+** [H16130] [H16133] [H16136] [H16139] [H16142]
+*/
+SQLITE_API int sqlite3_create_function(
   sqlite3 *db,
   const char *zFunctionName,
   int nArg,
@@ -3551,7 +3246,7 @@ int sqlite3_create_function(
   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
   void (*xFinal)(sqlite3_context*)
 );
-int sqlite3_create_function16(
+SQLITE_API int sqlite3_create_function16(
   sqlite3 *db,
   const void *zFunctionName,
   int nArg,
@@ -3563,7 +3258,7 @@ int sqlite3_create_function16(
 );
 
 /*
-** CAPI3REF: Text Encodings {F10267}
+** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
 **
 ** These constant define integer codes that represent the various
 ** text encodings supported by SQLite.
@@ -3576,23 +3271,26 @@ int sqlite3_create_function16(
 #define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
 
 /*
-** CAPI3REF: Obsolete Functions
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
 **
-** These functions are all now obsolete.  In order to maintain
-** backwards compatibility with older code, we continue to support
-** these functions.  However, new development projects should avoid
+** These functions are [deprecated].  In order to maintain
+** backwards compatibility with older code, these functions continue 
+** to be supported.  However, new applications should avoid
 ** the use of these functions.  To help encourage people to avoid
-** using these functions, we are not going to tell you want they do.
+** using these functions, we are not going to tell you what they do.
 */
-int sqlite3_aggregate_count(sqlite3_context*);
-int sqlite3_expired(sqlite3_stmt*);
-int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
-int sqlite3_global_recover(void);
-void sqlite3_thread_cleanup(void);
-int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#endif
 
 /*
-** CAPI3REF: Obtaining SQL Function Parameter Values {F15100}
+** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
 **
 ** The C-language implementation of SQL functions and aggregates uses
 ** this set of interface routines to access the parameter values on
@@ -3610,279 +3308,164 @@ int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
 ** Any attempt to use these routines on an [unprotected sqlite3_value]
 ** object results in undefined behavior.
 **
-** These routines work just like the corresponding 
-** [sqlite3_column_blob | sqlite3_column_* routines] except that 
-** these routines take a single [protected sqlite3_value] object pointer
-** instead of an [sqlite3_stmt*] pointer and an integer column number.
+** These routines work just like the corresponding [column access functions]
+** except that  these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
 **
-** The sqlite3_value_text16() interface extracts a UTF16 string
+** The sqlite3_value_text16() interface extracts a UTF-16 string
 ** in the native byte-order of the host machine.  The
 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
-** extract UTF16 strings as big-endian and little-endian respectively.
+** extract UTF-16 strings as big-endian and little-endian respectively.
 **
 ** The sqlite3_value_numeric_type() interface attempts to apply
 ** numeric affinity to the value.  This means that an attempt is
 ** made to convert the value to an integer or floating point.  If
 ** such a conversion is possible without loss of information (in other
-** words if the value is a string that looks like a number)
-** then the conversion is done.  Otherwise no conversion occurs.  The 
-** [SQLITE_INTEGER | datatype] after conversion is returned.
+** words, if the value is a string that looks like a number)
+** then the conversion is performed.  Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.
 **
-** Please pay particular attention to the fact that the pointer that
-** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
-** or [sqlite3_value_text16()].  
+** or [sqlite3_value_text16()].
 **
 ** These routines must be called from the same thread as
 ** the SQL function that supplied the [sqlite3_value*] parameters.
 **
-**
-** INVARIANTS:
-**
-** {F15103} The [sqlite3_value_blob(V)] interface converts the
-**          [protected sqlite3_value] object V into a blob and then returns a
-**          pointer to the converted value.
-**
-** {F15106} The [sqlite3_value_bytes(V)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_value_blob(V)] or
-**          [sqlite3_value_text(V)].
-**
-** {F15109} The [sqlite3_value_bytes16(V)] interface returns the
-**          number of bytes in the string (exclusive of the
-**          zero terminator on the string) that was returned by the
-**          most recent call to [sqlite3_value_text16(V)],
-**          [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
-**
-** {F15112} The [sqlite3_value_double(V)] interface converts the
-**          [protected sqlite3_value] object V into a floating point value and
-**          returns a copy of that value.
-**
-** {F15115} The [sqlite3_value_int(V)] interface converts the
-**          [protected sqlite3_value] object V into a 64-bit signed integer and
-**          returns the lower 32 bits of that integer.
-**
-** {F15118} The [sqlite3_value_int64(V)] interface converts the
-**          [protected sqlite3_value] object V into a 64-bit signed integer and
-**          returns a copy of that integer.
-**
-** {F15121} The [sqlite3_value_text(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated UTF-8 
-**          string and returns a pointer to that string.
-**
-** {F15124} The [sqlite3_value_text16(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 native byte order
-**          string and returns a pointer to that string.
-**
-** {F15127} The [sqlite3_value_text16be(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 big-endian
-**          string and returns a pointer to that string.
-**
-** {F15130} The [sqlite3_value_text16le(V)] interface converts the
-**          [protected sqlite3_value] object V into a zero-terminated 2-byte
-**          aligned UTF-16 little-endian
-**          string and returns a pointer to that string.
-**
-** {F15133} The [sqlite3_value_type(V)] interface returns
-**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
-**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
-**          the [sqlite3_value] object V.
-**
-** {F15136} The [sqlite3_value_numeric_type(V)] interface converts
-**          the [protected sqlite3_value] object V into either an integer or
-**          a floating point value if it can do so without loss of
-**          information, and returns one of [SQLITE_NULL],
-**          [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
-**          [SQLITE_BLOB] as appropriate for
-**          the [protected sqlite3_value] object V after the conversion attempt.
-*/
-const void *sqlite3_value_blob(sqlite3_value*);
-int sqlite3_value_bytes(sqlite3_value*);
-int sqlite3_value_bytes16(sqlite3_value*);
-double sqlite3_value_double(sqlite3_value*);
-int sqlite3_value_int(sqlite3_value*);
-sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
-const unsigned char *sqlite3_value_text(sqlite3_value*);
-const void *sqlite3_value_text16(sqlite3_value*);
-const void *sqlite3_value_text16le(sqlite3_value*);
-const void *sqlite3_value_text16be(sqlite3_value*);
-int sqlite3_value_type(sqlite3_value*);
-int sqlite3_value_numeric_type(sqlite3_value*);
-
-/*
-** CAPI3REF: Obtain Aggregate Function Context {F16210}
+** Requirements:
+** [H15103] [H15106] [H15109] [H15112] [H15115] [H15118] [H15121] [H15124]
+** [H15127] [H15130] [H15133] [H15136]
+*/
+SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
+SQLITE_API double sqlite3_value_double(sqlite3_value*);
+SQLITE_API int sqlite3_value_int(sqlite3_value*);
+SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
+SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
+SQLITE_API int sqlite3_value_type(sqlite3_value*);
+SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
+
+/*
+** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
 **
 ** The implementation of aggregate SQL functions use this routine to allocate
-** a structure for storing their state.  
-** The first time the sqlite3_aggregate_context() routine is
-** is called for a particular aggregate, SQLite allocates nBytes of memory
-** zeros that memory, and returns a pointer to it.
-** On second and subsequent calls to sqlite3_aggregate_context()
-** for the same aggregate function index, the same buffer is returned.
-** The implementation
-** of the aggregate can use the returned buffer to accumulate data.
+** a structure for storing their state.
+**
+** The first time the sqlite3_aggregate_context() routine is called for a
+** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
+** memory, and returns a pointer to it. On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function index,
+** the same buffer is returned. The implementation of the aggregate can use
+** the returned buffer to accumulate data.
 **
 ** SQLite automatically frees the allocated buffer when the aggregate
 ** query concludes.
 **
-** The first parameter should be a copy of the 
-** [sqlite3_context | SQL function context] that is the first
-** parameter to the callback routine that implements the aggregate
-** function.
+** The first parameter should be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the callback routine that implements the aggregate function.
 **
 ** This routine must be called from the same thread in which
 ** the aggregate SQL function is running.
 **
-** INVARIANTS:
-**
-** {F16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
-**          a particular instance of an aggregate function (for a particular
-**          context C) causes SQLite to allocation N bytes of memory,
-**          zero that memory, and return a pointer to the allocationed
-**          memory.
-**
-** {F16213} If a memory allocation error occurs during
-**          [sqlite3_aggregate_context(C,N)] then the function returns 0.
-**
-** {F16215} Second and subsequent invocations of
-**          [sqlite3_aggregate_context(C,N)] for the same context pointer C
-**          ignore the N parameter and return a pointer to the same
-**          block of memory returned by the first invocation.
-**
-** {F16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
-**          automatically freed on the next call to [sqlite3_reset()]
-**          or [sqlite3_finalize()] for the [prepared statement] containing
-**          the aggregate function associated with context C.
+** Requirements:
+** [H16211] [H16213] [H16215] [H16217]
 */
-void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
+SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
 
 /*
-** CAPI3REF: User Data For Functions {F16240}
+** CAPI3REF: User Data For Functions {H16240} <S20200>
 **
 ** The sqlite3_user_data() interface returns a copy of
 ** the pointer that was the pUserData parameter (the 5th parameter)
-** of the the [sqlite3_create_function()]
+** of the [sqlite3_create_function()]
 ** and [sqlite3_create_function16()] routines that originally
 ** registered the application defined function. {END}
 **
 ** This routine must be called from the same thread in which
 ** the application-defined function is running.
 **
-** INVARIANTS:
-**
-** {F16243} The [sqlite3_user_data(C)] interface returns a copy of the
-**          P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
-**          registered the SQL function associated with 
-**          [sqlite3_context] C.
+** Requirements:
+** [H16243]
 */
-void *sqlite3_user_data(sqlite3_context*);
+SQLITE_API void *sqlite3_user_data(sqlite3_context*);
 
 /*
-** CAPI3REF: Database Connection For Functions {F16250}
+** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
 **
 ** The sqlite3_context_db_handle() interface returns a copy of
 ** the pointer to the [database connection] (the 1st parameter)
-** of the the [sqlite3_create_function()]
+** of the [sqlite3_create_function()]
 ** and [sqlite3_create_function16()] routines that originally
 ** registered the application defined function.
 **
-** INVARIANTS:
-**
-** {F16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
-**          D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
-**          registered the SQL function associated with 
-**          [sqlite3_context] C.
+** Requirements:
+** [H16253]
 */
-sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
 
 /*
-** CAPI3REF: Function Auxiliary Data {F16270}
+** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
 **
 ** The following two functions may be used by scalar SQL functions to
-** associate meta-data with argument values. If the same value is passed to
+** associate metadata with argument values. If the same value is passed to
 ** multiple invocations of the same SQL function during query execution, under
-** some circumstances the associated meta-data may be preserved. This may
+** some circumstances the associated metadata may be preserved. This may
 ** be used, for example, to add a regular-expression matching scalar
 ** function. The compiled version of the regular expression is stored as
-** meta-data associated with the SQL value passed as the regular expression
+** metadata associated with the SQL value passed as the regular expression
 ** pattern.  The compiled regular expression can be reused on multiple
 ** invocations of the same function so that the original pattern string
 ** does not need to be recompiled on each invocation.
 **
-** The sqlite3_get_auxdata() interface returns a pointer to the meta-data
+** The sqlite3_get_auxdata() interface returns a pointer to the metadata
 ** associated by the sqlite3_set_auxdata() function with the Nth argument
-** value to the application-defined function.
-** If no meta-data has been ever been set for the Nth
-** argument of the function, or if the cooresponding function parameter
-** has changed since the meta-data was set, then sqlite3_get_auxdata()
-** returns a NULL pointer.
-**
-** The sqlite3_set_auxdata() interface saves the meta-data
-** pointed to by its 3rd parameter as the meta-data for the N-th
+** value to the application-defined function. If no metadata has been ever
+** been set for the Nth argument of the function, or if the corresponding
+** function parameter has changed since the meta-data was set,
+** then sqlite3_get_auxdata() returns a NULL pointer.
+**
+** The sqlite3_set_auxdata() interface saves the metadata
+** pointed to by its 3rd parameter as the metadata for the N-th
 ** argument of the application-defined function.  Subsequent
 ** calls to sqlite3_get_auxdata() might return this data, if it has
-** not been destroyed. 
-** If it is not NULL, SQLite will invoke the destructor 
+** not been destroyed.
+** If it is not NULL, SQLite will invoke the destructor
 ** function given by the 4th parameter to sqlite3_set_auxdata() on
-** the meta-data when the corresponding function parameter changes
+** the metadata when the corresponding function parameter changes
 ** or when the SQL statement completes, whichever comes first.
 **
-** SQLite is free to call the destructor and drop meta-data on
-** any parameter of any function at any time.  The only guarantee
-** is that the destructor will be called before the metadata is
-** dropped.
+** SQLite is free to call the destructor and drop metadata on any
+** parameter of any function at any time.  The only guarantee is that
+** the destructor will be called before the metadata is dropped.
 **
-** In practice, meta-data is preserved between function calls for
+** In practice, metadata is preserved between function calls for
 ** expressions that are constant at compile time. This includes literal
 ** values and SQL variables.
 **
 ** These routines must be called from the same thread in which
 ** the SQL function is running.
 **
-** INVARIANTS:
-**
-** {F16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
-**          to metadata associated with the Nth parameter of the SQL function
-**          whose context is C, or NULL if there is no metadata associated
-**          with that parameter.
-**
-** {F16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
-**          pointer P to the Nth parameter of the SQL function with context
-**          C.
-**
-** {F16276} SQLite will invoke the destructor D with a single argument
-**          which is the metadata pointer P following a call to
-**          [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
-**          the metadata.
-**
-** {F16277} SQLite ceases to hold metadata for an SQL function parameter
-**          when the value of that parameter changes.
-**
-** {F16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
-**          is called for any prior metadata associated with the same function
-**          context C and parameter N.
-**
-** {F16279} SQLite will call destructors for any metadata it is holding
-**          in a particular [prepared statement] S when either
-**          [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
+** Requirements:
+** [H16272] [H16274] [H16276] [H16277] [H16278] [H16279]
 */
-void *sqlite3_get_auxdata(sqlite3_context*, int N);
-void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
+SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
+SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
 
 
 /*
-** CAPI3REF: Constants Defining Special Destructor Behavior {F10280}
+** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
 **
-** These are special value for the destructor that is passed in as the
+** These are special values for the destructor that is passed in as the
 ** final argument to routines like [sqlite3_result_blob()].  If the destructor
 ** argument is SQLITE_STATIC, it means that the content pointer is constant
-** and will never change.  It does not need to be destroyed.  The 
+** and will never change.  It does not need to be destroyed.  The
 ** SQLITE_TRANSIENT value means that the content will likely change in
 ** the near future and that SQLite should make its own private copy of
 ** the content before returning.
@@ -3895,30 +3478,28 @@ typedef void (*sqlite3_destructor_type)(void*);
 #define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
 
 /*
-** CAPI3REF: Setting The Result Of An SQL Function {F16400}
+** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
 **
 ** These routines are used by the xFunc or xFinal callbacks that
 ** implement SQL functions and aggregates.  See
 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
 ** for additional information.
 **
-** These functions work very much like the 
-** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used
-** to bind values to host parameters in prepared statements.
-** Refer to the
-** [sqlite3_bind_blob | sqlite3_bind_* documentation] for
-** additional information.
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
 **
 ** The sqlite3_result_blob() interface sets the result from
-** an application defined function to be the BLOB whose content is pointed
+** an application-defined function to be the BLOB whose content is pointed
 ** to by the second parameter and which is N bytes long where N is the
-** third parameter. 
-** The sqlite3_result_zeroblob() inerfaces set the result of
-** the application defined function to be a BLOB containing all zero
+** third parameter.
+**
+** The sqlite3_result_zeroblob() interfaces set the result of
+** the application-defined function to be a BLOB containing all zero
 ** bytes and N bytes in size, where N is the value of the 2nd parameter.
 **
 ** The sqlite3_result_double() interface sets the result from
-** an application defined function to be a floating point value specified
+** an application-defined function to be a floating point value specified
 ** by its 2nd argument.
 **
 ** The sqlite3_result_error() and sqlite3_result_error16() functions
@@ -3926,8 +3507,8 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite uses the string pointed to by the
 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
 ** as the text of an error message.  SQLite interprets the error
-** message string from sqlite3_result_error() as UTF8. SQLite
-** interprets the string from sqlite3_result_error16() as UTF16 in native
+** message string from sqlite3_result_error() as UTF-8. SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
 ** byte order.  If the third parameter to sqlite3_result_error()
 ** or sqlite3_result_error16() is negative then SQLite takes as the error
 ** message all text up through the first zero character.
@@ -3935,7 +3516,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** sqlite3_result_error16() is non-negative then SQLite takes that many
 ** bytes (not characters) from the 2nd parameter as the error message.
 ** The sqlite3_result_error() and sqlite3_result_error16()
-** routines make a copy private copy of the error message text before
+** routines make a private copy of the error message text before
 ** they return.  Hence, the calling function can deallocate or
 ** modify the text after they return without harm.
 ** The sqlite3_result_error_code() function changes the error code
@@ -3943,11 +3524,11 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the error code is SQLITE_ERROR.  A subsequent call to sqlite3_result_error()
 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
 **
-** The sqlite3_result_toobig() interface causes SQLite
-** to throw an error indicating that a string or BLOB is to long
-** to represent.  The sqlite3_result_nomem() interface
-** causes SQLite to throw an exception indicating that the a
-** memory allocation failed.
+** The sqlite3_result_toobig() interface causes SQLite to throw an error
+** indicating that a string or BLOB is to long to represent.
+**
+** The sqlite3_result_nomem() interface causes SQLite to throw an error
+** indicating that a memory allocation failed.
 **
 ** The sqlite3_result_int() interface sets the return value
 ** of the application-defined function to be the 32-bit signed integer
@@ -3959,7 +3540,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** The sqlite3_result_null() interface sets the return value
 ** of the application-defined function to be NULL.
 **
-** The sqlite3_result_text(), sqlite3_result_text16(), 
+** The sqlite3_result_text(), sqlite3_result_text16(),
 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
 ** set the return value of the application-defined function to be
 ** a text string which is represented as UTF-8, UTF-16 native byte order,
@@ -3967,7 +3548,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite takes the text result from the application from
 ** the 2nd parameter of the sqlite3_result_text* interfaces.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
-** is negative, then SQLite takes result text from the 2nd parameter 
+** is negative, then SQLite takes result text from the 2nd parameter
 ** through the first zero character.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
 ** is non-negative, then as many bytes (not characters) of the text
@@ -3975,13 +3556,13 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** function result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
-** function as the destructor on the text or blob result when it has
-** finished using that result.
-** If the 4th parameter to the sqlite3_result_text* interfaces
-** or sqlite3_result_blob is the special constant SQLITE_STATIC, then
-** SQLite assumes that the text or blob result is constant space and
-** does not copy the space or call a destructor when it has
+** function as the destructor on the text or BLOB result when it has
 ** finished using that result.
+** If the 4th parameter to the sqlite3_result_text* interfaces or to
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the content of the parameter nor call a destructor on the content
+** when it has finished using that result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
 ** then SQLite makes a copy of the result into space obtained from
@@ -3991,134 +3572,43 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the application-defined function to be a copy the
 ** [unprotected sqlite3_value] object specified by the 2nd parameter.  The
 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
-** so that [sqlite3_value] specified in the parameter may change or
+** so that the [sqlite3_value] specified in the parameter may change or
 ** be deallocated after sqlite3_result_value() returns without harm.
 ** A [protected sqlite3_value] object may always be used where an
 ** [unprotected sqlite3_value] object is required, so either
 ** kind of [sqlite3_value] object can be used with this interface.
 **
-** If these routines are called from within the different thread 
-** than the one containing the application-defined function that recieved
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
 ** the [sqlite3_context] pointer, the results are undefined.
 **
-** INVARIANTS:
-**
-** {F16403} The default return value from any SQL function is NULL.
-**
-** {F16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
-**          return value of function C to be a blob that is N bytes
-**          in length and with content pointed to by V.
-**
-** {F16409} The [sqlite3_result_double(C,V)] interface changes the
-**          return value of function C to be the floating point value V.
-**
-** {F16412} The [sqlite3_result_error(C,V,N)] interface changes the return
-**          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF8 error message copied from V up to the
-**          first zero byte or until N bytes are read if N is positive.
-**
-** {F16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
-**          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF16 native byte order error message
-**          copied from V up to the first zero terminator or until N bytes
-**          are read if N is positive.
-**
-** {F16418} The [sqlite3_result_error_toobig(C)] interface changes the return
-**          value of the function C to be an exception with error code
-**          [SQLITE_TOOBIG] and an appropriate error message.
-**
-** {F16421} The [sqlite3_result_error_nomem(C)] interface changes the return
-**          value of the function C to be an exception with error code
-**          [SQLITE_NOMEM] and an appropriate error message.
-**
-** {F16424} The [sqlite3_result_error_code(C,E)] interface changes the return
-**          value of the function C to be an exception with error code E.
-**          The error message text is unchanged.
-**
-** {F16427} The [sqlite3_result_int(C,V)] interface changes the
-**          return value of function C to be the 32-bit integer value V.
-**
-** {F16430} The [sqlite3_result_int64(C,V)] interface changes the
-**          return value of function C to be the 64-bit integer value V.
-**
-** {F16433} The [sqlite3_result_null(C)] interface changes the
-**          return value of function C to be NULL.
-**
-** {F16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF8 string
-**          V up to the first zero if N is negative
-**          or the first N bytes of V if N is non-negative.
-**
-** {F16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 native byte order
-**          string V up to the first zero if N is
-**          negative or the first N bytes of V if N is non-negative.
-**
-** {F16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 big-endian
-**          string V up to the first zero if N is
-**          is negative or the first N bytes or V if N is non-negative.
-**
-** {F16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 little-endian
-**          string V up to the first zero if N is
-**          negative or the first N bytes of V if N is non-negative.
-**
-** {F16448} The [sqlite3_result_value(C,V)] interface changes the
-**          return value of function C to be [unprotected sqlite3_value]
-**          object V.
-**
-** {F16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
-**          return value of function C to be an N-byte blob of all zeros.
-**
-** {F16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
-**          interfaces make a copy of their error message strings before
-**          returning.
-**
-** {F16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
-**          then no destructor is ever called on the pointer V and SQLite
-**          assumes that V is immutable.
-**
-** {F16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is the constant
-**          [SQLITE_TRANSIENT] then the interfaces makes a copy of the
-**          content of V and retains the copy.
-**
-** {F16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
-**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
-**          [sqlite3_result_text16be(C,V,N,D)], or
-**          [sqlite3_result_text16le(C,V,N,D)] is some value other than
-**          the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then 
-**          SQLite will invoke the destructor D with V as its only argument
-**          when it has finished with the V value.
-*/
-void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
-void sqlite3_result_double(sqlite3_context*, double);
-void sqlite3_result_error(sqlite3_context*, const char*, int);
-void sqlite3_result_error16(sqlite3_context*, const void*, int);
-void sqlite3_result_error_toobig(sqlite3_context*);
-void sqlite3_result_error_nomem(sqlite3_context*);
-void sqlite3_result_error_code(sqlite3_context*, int);
-void sqlite3_result_int(sqlite3_context*, int);
-void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
-void sqlite3_result_null(sqlite3_context*);
-void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
-void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
-void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
-void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
-void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
-void sqlite3_result_zeroblob(sqlite3_context*, int n);
-
-/*
-** CAPI3REF: Define New Collating Sequences {F16600}
+** Requirements:
+** [H16403] [H16406] [H16409] [H16412] [H16415] [H16418] [H16421] [H16424]
+** [H16427] [H16430] [H16433] [H16436] [H16439] [H16442] [H16445] [H16448]
+** [H16451] [H16454] [H16457] [H16460] [H16463]
+*/
+SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
+SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
+SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
+SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
+SQLITE_API void sqlite3_result_null(sqlite3_context*);
+SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
+SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
+
+/*
+** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
 **
 ** These functions are used to add new collation sequences to the
-** [sqlite3*] handle specified as the first argument. 
+** [database connection] specified as the first argument.
 **
 ** The name of the new collation sequence is specified as a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
@@ -4126,95 +3616,52 @@ void sqlite3_result_zeroblob(sqlite3_context*, int n);
 ** the name is passed as the second function argument.
 **
 ** The third argument may be one of the constants [SQLITE_UTF8],
-** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
+** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
 ** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian or UTF-16 big-endian respectively. The
-** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
+** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
+** third argument might also be [SQLITE_UTF16] to indicate that the routine
+** expects pointers to be UTF-16 strings in the native byte order, or the
+** argument can be [SQLITE_UTF16_ALIGNED] if the
 ** the routine expects pointers to 16-bit word aligned strings
-** of UTF16 in the native byte order of the host computer.
+** of UTF-16 in the native byte order.
 **
 ** A pointer to the user supplied routine must be passed as the fifth
 ** argument.  If it is NULL, this is the same as deleting the collation
 ** sequence (so that SQLite cannot call it anymore).
-** Each time the application
-** supplied function is invoked, it is passed a copy of the void* passed as
-** the fourth argument to sqlite3_create_collation() or
-** sqlite3_create_collation16() as its first parameter.
+** Each time the application supplied function is invoked, it is passed
+** as its first parameter a copy of the void* passed as the fourth argument
+** to sqlite3_create_collation() or sqlite3_create_collation16().
 **
 ** The remaining arguments to the application-supplied routine are two strings,
 ** each represented by a (length, data) pair and encoded in the encoding
 ** that was passed as the third argument when the collation sequence was
-** registered. {END} The application defined collation routine should
-** return negative, zero or positive if
-** the first string is less than, equal to, or greater than the second
-** string. i.e. (STRING1 - STRING2).
+** registered. {END}  The application defined collation routine should
+** return negative, zero or positive if the first string is less than,
+** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
 **
 ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** excapt that it takes an extra argument which is a destructor for
+** except that it takes an extra argument which is a destructor for
 ** the collation.  The destructor is called when the collation is
 ** destroyed and is passed a copy of the fourth parameter void* pointer
 ** of the sqlite3_create_collation_v2().
-** Collations are destroyed when
-** they are overridden by later calls to the collation creation functions
-** or when the [sqlite3*] database handle is closed using [sqlite3_close()].
-**
-** INVARIANTS:
-**
-** {F16603} A successful call to the
-**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
-**          registers function F as the comparison function used to
-**          implement collation X on [database connection] B for
-**          databases having encoding E.
-**
-** {F16604} SQLite understands the X parameter to
-**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
-**          UTF-8 string in which case is ignored for ASCII characters and
-**          is significant for non-ASCII characters.
-**
-** {F16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          with the same values for B, X, and E, override prior values
-**          of P, F, and D.
-**
-** {F16609} The destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          is not NULL then it is called with argument P when the
-**          collating function is dropped by SQLite.
+** Collations are destroyed when they are overridden by later calls to the
+** collation creation functions or when the [database connection] is closed
+** using [sqlite3_close()].
 **
-** {F16612} A collating function is dropped when it is overloaded.
+** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
 **
-** {F16615} A collating function is dropped when the database connection
-**          is closed using [sqlite3_close()].
-**
-** {F16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
-**          is passed through as the first parameter to the comparison
-**          function F for all subsequent invocations of F.
-**
-** {F16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
-**          the same as a call to [sqlite3_create_collation_v2()] with
-**          the same parameters and a NULL destructor.
-**
-** {F16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
-**          SQLite uses the comparison function F for all text comparison
-**          operations on [database connection] B on text values that
-**          use the collating sequence name X.
-**
-** {F16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
-**          as [sqlite3_create_collation(B,X,E,P,F)] except that the
-**          collation name X is understood as UTF-16 in native byte order
-**          instead of UTF-8.
-**
-** {F16630} When multiple comparison functions are available for the same
-**          collating sequence, SQLite chooses the one whose text encoding
-**          requires the least amount of conversion from the default
-**          text encoding of the database.
+** Requirements:
+** [H16603] [H16604] [H16606] [H16609] [H16612] [H16615] [H16618] [H16621]
+** [H16624] [H16627] [H16630]
 */
-int sqlite3_create_collation(
+SQLITE_API int sqlite3_create_collation(
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
   void*,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
-int sqlite3_create_collation_v2(
+SQLITE_API int sqlite3_create_collation_v2(
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
@@ -4222,68 +3669,49 @@ int sqlite3_create_collation_v2(
   int(*xCompare)(void*,int,const void*,int,const void*),
   void(*xDestroy)(void*)
 );
-int sqlite3_create_collation16(
+SQLITE_API int sqlite3_create_collation16(
   sqlite3*, 
-  const char *zName, 
+  const void *zName,
   int eTextRep, 
   void*,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
 /*
-** CAPI3REF: Collation Needed Callbacks {F16700}
+** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
 **
 ** To avoid having to register all collation sequences before a database
 ** can be used, a single callback function may be registered with the
-** database handle to be called whenever an undefined collation sequence is
-** required.
+** [database connection] to be called whenever an undefined collation
+** sequence is required.
 **
 ** If the function is registered using the sqlite3_collation_needed() API,
 ** then it is passed the names of undefined collation sequences as strings
-** encoded in UTF-8. {F16703} If sqlite3_collation_needed16() is used, the names
-** are passed as UTF-16 in machine native byte order. A call to either
-** function replaces any existing callback.
+** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** A call to either function replaces any existing callback.
 **
 ** When the callback is invoked, the first argument passed is a copy
 ** of the second argument to sqlite3_collation_needed() or
 ** sqlite3_collation_needed16().  The second argument is the database
-** handle.  The third argument is one of [SQLITE_UTF8],
-** [SQLITE_UTF16BE], or [SQLITE_UTF16LE], indicating the most
-** desirable form of the collation sequence function required.
-** The fourth parameter is the name of the
+** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required.  The fourth parameter is the name of the
 ** required collation sequence.
 **
 ** The callback function should register the desired collation using
 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
 ** [sqlite3_create_collation_v2()].
 **
-** INVARIANTS:
-**
-** {F16702} A successful call to [sqlite3_collation_needed(D,P,F)]
-**          or [sqlite3_collation_needed16(D,P,F)] causes
-**          the [database connection] D to invoke callback F with first
-**          parameter P whenever it needs a comparison function for a
-**          collating sequence that it does not know about.
-**
-** {F16704} Each successful call to [sqlite3_collation_needed()] or
-**          [sqlite3_collation_needed16()] overrides the callback registered
-**          on the same [database connection] by prior calls to either
-**          interface.
-**
-** {F16706} The name of the requested collating function passed in the
-**          4th parameter to the callback is in UTF-8 if the callback
-**          was registered using [sqlite3_collation_needed()] and
-**          is in UTF-16 native byte order if the callback was
-**          registered using [sqlite3_collation_needed16()].
-**
-** 
+** Requirements:
+** [H16702] [H16704] [H16706]
 */
-int sqlite3_collation_needed(
+SQLITE_API int sqlite3_collation_needed(
   sqlite3*, 
   void*, 
   void(*)(void*,sqlite3*,int eTextRep,const char*)
 );
-int sqlite3_collation_needed16(
+SQLITE_API int sqlite3_collation_needed16(
   sqlite3*, 
   void*,
   void(*)(void*,sqlite3*,int eTextRep,const void*)
@@ -4296,7 +3724,7 @@ int sqlite3_collation_needed16(
 ** The code to implement this API is not available in the public release
 ** of SQLite.
 */
-int sqlite3_key(
+SQLITE_API int sqlite3_key(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The key */
 );
@@ -4309,134 +3737,149 @@ int sqlite3_key(
 ** The code to implement this API is not available in the public release
 ** of SQLite.
 */
-int sqlite3_rekey(
+SQLITE_API int sqlite3_rekey(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The new key */
 );
 
 /*
-** CAPI3REF:  Suspend Execution For A Short Time {F10530}
+** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
 **
-** The sqlite3_sleep() function
-** causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** If the operating system does not support sleep requests with 
-** millisecond time resolution, then the time will be rounded up to 
-** the nearest second. The number of milliseconds of sleep actually 
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** SQLite implements this interface by calling the xSleep()
 ** method of the default [sqlite3_vfs] object.
 **
-** INVARIANTS:
-**
-** {F10533} The [sqlite3_sleep(M)] interface invokes the xSleep
-**          method of the default [sqlite3_vfs|VFS] in order to
-**          suspend execution of the current thread for at least
-**          M milliseconds.
-**
-** {F10536} The [sqlite3_sleep(M)] interface returns the number of
-**          milliseconds of sleep actually requested of the operating
-**          system, which might be larger than the parameter M.
+** Requirements: [H10533] [H10536]
 */
-int sqlite3_sleep(int);
+SQLITE_API int sqlite3_sleep(int);
 
 /*
-** CAPI3REF:  Name Of The Folder Holding Temporary Files {F10310}
+** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
 **
 ** If this global variable is made to point to a string which is
-** the name of a folder (a.ka. directory), then all temporary files
+** the name of a folder (a.k.a. directory), then all temporary files
 ** created by SQLite will be placed in that directory.  If this variable
-** is NULL pointer, then SQLite does a search for an appropriate temporary
-** file directory.
-**
-** It is not safe to modify this variable once a database connection
-** has been opened.  It is intended that this variable be set once
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time.  It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
 ** as part of process initialization and before any SQLite interface
-** routines have been call and remain unchanged thereafter.
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** The [temp_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc].  Furthermore,
+** the [temp_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from 
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [temp_store_directory pragma] should be avoided.
 */
-SQLITE_EXTERN char *sqlite3_temp_directory;
+SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
 
 /*
-** CAPI3REF:  Test To See If The Database Is In Auto-Commit Mode {F12930}
+** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
+** KEYWORDS: {autocommit mode}
 **
-** The sqlite3_get_autocommit() interfaces returns non-zero or
+** The sqlite3_get_autocommit() interface returns non-zero or
 ** zero if the given database connection is or is not in autocommit mode,
-** respectively.   Autocommit mode is on
-** by default.  Autocommit mode is disabled by a [BEGIN] statement.
-** Autocommit mode is reenabled by a [COMMIT] or [ROLLBACK].
+** respectively.  Autocommit mode is on by default.
+** Autocommit mode is disabled by a [BEGIN] statement.
+** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
 **
 ** If certain kinds of errors occur on a statement within a multi-statement
-** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR], 
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
 ** transaction might be rolled back automatically.  The only way to
-** find out if SQLite automatically rolled back the transaction after
+** find out whether SQLite automatically rolled back the transaction after
 ** an error is to use this function.
 **
-** INVARIANTS:
-**
-** {F12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
-**          zero if the [database connection] D is or is not in autocommit
-**          mode, respectively.
-**
-** {F12932} Autocommit mode is on by default.
+** If another thread changes the autocommit status of the database
+** connection while this routine is running, then the return value
+** is undefined.
 **
-** {F12933} Autocommit mode is disabled by a successful [BEGIN] statement.
+** Requirements: [H12931] [H12932] [H12933] [H12934]
+*/
+SQLITE_API int sqlite3_get_autocommit(sqlite3*);
+
+/*
+** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
 **
-** {F12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
-**          statement.
-** 
+** The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs.  The [database connection]
+** returned by sqlite3_db_handle is the same [database connection] that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
 **
-** LIMITATIONS:
-***
-** {U12936} If another thread changes the autocommit status of the database
-**          connection while this routine is running, then the return value
-**          is undefined.
+** Requirements: [H13123]
 */
-int sqlite3_get_autocommit(sqlite3*);
+SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 
 /*
-** CAPI3REF:  Find The Database Handle Of A Prepared Statement {F13120}
+** CAPI3REF: Find the next prepared statement {H13140} <S60600>
 **
-** The sqlite3_db_handle interface
-** returns the [sqlite3*] database handle to which a
-** [prepared statement] belongs.
-** The database handle returned by sqlite3_db_handle
-** is the same database handle that was
-** the first argument to the [sqlite3_prepare_v2()] or its variants
-** that was used to create the statement in the first place.
+** This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb.  If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb.  If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
 **
-** INVARIANTS:
+** The [database connection] pointer D in a call to
+** [sqlite3_next_stmt(D,S)] must refer to an open database
+** connection and in particular must not be a NULL pointer.
 **
-** {F13123} The [sqlite3_db_handle(S)] interface returns a pointer
-**          to the [database connection] associated with
-**          [prepared statement] S.
+** Requirements: [H13143] [H13146] [H13149] [H13152]
 */
-sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
-
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Commit And Rollback Notification Callbacks {F12950}
+** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
 **
 ** The sqlite3_commit_hook() interface registers a callback
-** function to be invoked whenever a transaction is committed.
+** function to be invoked whenever a transaction is [COMMIT | committed].
 ** Any callback set by a previous call to sqlite3_commit_hook()
 ** for the same database connection is overridden.
 ** The sqlite3_rollback_hook() interface registers a callback
-** function to be invoked whenever a transaction is committed.
+** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
 ** Any callback set by a previous call to sqlite3_commit_hook()
 ** for the same database connection is overridden.
-** The pArg argument is passed through
-** to the callback.  If the callback on a commit hook function 
-** returns non-zero, then the commit is converted into a rollback.
+** The pArg argument is passed through to the callback.
+** If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
 **
 ** If another function was previously registered, its
 ** pArg value is returned.  Otherwise NULL is returned.
 **
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
 ** Registering a NULL function disables the callback.
 **
-** For the purposes of this API, a transaction is said to have been 
+** When the commit hook callback routine returns zero, the [COMMIT]
+** operation is allowed to continue normally.  If the commit hook
+** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
+** The rollback hook is invoked on a rollback that results from a commit
+** hook returning non-zero, just as it would be with any other rollback.
+**
+** For the purposes of this API, a transaction is said to have been
 ** rolled back if an explicit "ROLLBACK" statement is executed, or
 ** an error or constraint causes an implicit rollback to occur.
 ** The rollback callback is not invoked if a transaction is
@@ -4445,206 +3888,137 @@ sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 ** rolled back because a commit callback returned non-zero.
 ** <todo> Check on this </todo>
 **
-** These are experimental interfaces and are subject to change.
-**
-** INVARIANTS:
-**
-** {F12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
-**          callback function F to be invoked with argument P whenever
-**          a transaction commits on [database connection] D.
+** See also the [sqlite3_update_hook()] interface.
 **
-** {F12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
-**
-** {F12953} Each call to [sqlite3_commit_hook()] overwrites the callback
-**          registered by prior calls.
-**
-** {F12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
-**          then the commit hook callback is cancelled and no callback
-**          is invoked when a transaction commits.
-**
-** {F12955} If the commit callback returns non-zero then the commit is
-**          converted into a rollback.
-**
-** {F12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
-**          callback function F to be invoked with argument P whenever
-**          a transaction rolls back on [database connection] D.
-**
-** {F12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
-**
-** {F12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
-**          registered by prior calls.
-**
-** {F12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
-**          then the rollback hook callback is cancelled and no callback
-**          is invoked when a transaction rolls back.
+** Requirements:
+** [H12951] [H12952] [H12953] [H12954] [H12955]
+** [H12961] [H12962] [H12963] [H12964]
 */
-void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
-void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
+SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
+SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
 
 /*
-** CAPI3REF: Data Change Notification Callbacks {F12970}
+** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
 **
-** The sqlite3_update_hook() interface
-** registers a callback function with the database connection identified by the 
-** first argument to be invoked whenever a row is updated, inserted or deleted.
-** Any callback set by a previous call to this function for the same 
-** database connection is overridden.
+** The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted.
+** Any callback set by a previous call to this function
+** for the same database connection is overridden.
 **
-** The second argument is a pointer to the function to invoke when a 
-** row is updated, inserted or deleted. 
-** The first argument to the callback is
-** a copy of the third argument to sqlite3_update_hook().
-** The second callback 
-** argument is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
-** depending on the operation that caused the callback to be invoked.
-** The third and 
-** fourth arguments to the callback contain pointers to the database and 
-** table name containing the affected row.
-** The final callback parameter is 
-** the rowid of the row.
-** In the case of an update, this is the rowid after 
-** the update takes place.
+** The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted.
+** The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** The final callback parameter is the [rowid] of the row.
+** In the case of an update, this is the [rowid] after the update takes place.
 **
 ** The update hook is not invoked when internal system tables are
 ** modified (i.e. sqlite_master and sqlite_sequence).
 **
-** If another function was previously registered, its pArg value
-** is returned.  Otherwise NULL is returned.
-**
-** INVARIANTS:
-**
-** {F12971} The [sqlite3_update_hook(D,F,P)] interface causes callback
-**          function F to be invoked with first parameter P whenever
-**          a table row is modified, inserted, or deleted on
-**          [database connection] D.
-**
-** {F12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
-**          of P for the previous call on the same [database connection] D,
-**          or NULL for the first call.
+** In the current implementation, the update hook
+** is not invoked when duplication rows are deleted because of an
+** [ON CONFLICT | ON CONFLICT REPLACE] clause.  Nor is the update hook
+** invoked when rows are deleted using the [truncate optimization].
+** The exceptions defined in this paragraph might change in a future
+** release of SQLite.
 **
-** {F12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
-**          is NULL then the no update callbacks are made.
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
-** {F12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
-**          to the same interface on the same [database connection] D.
-**
-** {F12979} The update hook callback is not invoked when internal system
-**          tables such as sqlite_master and sqlite_sequence are modified.
+** If another function was previously registered, its pArg value
+** is returned.  Otherwise NULL is returned.
 **
-** {F12981} The second parameter to the update callback 
-**          is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
-**          depending on the operation that caused the callback to be invoked.
+** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
+** interfaces.
 **
-** {F12983} The third and fourth arguments to the callback contain pointers
-**          to zero-terminated UTF-8 strings which are the names of the
-**          database and table that is being updated.
-
-** {F12985} The final callback parameter is the rowid of the row after
-**          the change occurs.
+** Requirements:
+** [H12971] [H12973] [H12975] [H12977] [H12979] [H12981] [H12983] [H12986]
 */
-void *sqlite3_update_hook(
+SQLITE_API void *sqlite3_update_hook(
   sqlite3*, 
   void(*)(void *,int ,char const *,char const *,sqlite3_int64),
   void*
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Shared Pager Cache {F10330}
+** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
+** KEYWORDS: {shared cache}
 **
 ** This routine enables or disables the sharing of the database cache
-** and schema data structures between connections to the same database.
-** Sharing is enabled if the argument is true and disabled if the argument
-** is false.
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.
 **
-** Cache sharing is enabled and disabled
-** for an entire process. {END} This is a change as of SQLite version 3.5.0.
-** In prior versions of SQLite, sharing was
-** enabled or disabled for each thread separately.
+** Cache sharing is enabled and disabled for an entire process.
+** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
 **
 ** The cache sharing mode set by this interface effects all subsequent
 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
 ** Existing database connections continue use the sharing mode
 ** that was in effect at the time they were opened.
 **
-** Virtual tables cannot be used with a shared cache.   When shared
+** Virtual tables cannot be used with a shared cache.  When shared
 ** cache is enabled, the [sqlite3_create_module()] API used to register
 ** virtual tables will always return an error.
 **
-** This routine returns [SQLITE_OK] if shared cache was
-** enabled or disabled successfully.  An [error code]
-** is returned otherwise.
+** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully.  An [error code] is returned otherwise.
 **
 ** Shared cache is disabled by default. But this might change in
 ** future releases of SQLite.  Applications that care about shared
 ** cache setting should set it explicitly.
 **
-** INVARIANTS:
-** 
-** {F10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
-**          will enable or disable shared cache mode for any subsequently
-**          created [database connection] in the same process.
-**
-** {F10336} When shared cache is enabled, the [sqlite3_create_module()]
-**          interface will always return an error.
+** See Also:  [SQLite Shared-Cache Mode]
 **
-** {F10337} The [sqlite3_enable_shared_cache(B)] interface returns
-**          [SQLITE_OK] if shared cache was enabled or disabled successfully.
-**
-** {F10339} Shared cache is disabled by default.
+** Requirements: [H10331] [H10336] [H10337] [H10339]
 */
-int sqlite3_enable_shared_cache(int);
+SQLITE_API int sqlite3_enable_shared_cache(int);
 
 /*
-** CAPI3REF:  Attempt To Free Heap Memory {F17340}
-**
-** The sqlite3_release_memory() interface attempts to
-** free N bytes of heap memory by deallocating non-essential memory
-** allocations held by the database labrary. {END}  Memory used
-** to cache database pages to improve performance is an example of
-** non-essential memory.  Sqlite3_release_memory() returns
-** the number of bytes actually freed, which might be more or less
-** than the amount requested.
+** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
 **
-** INVARIANTS:
+** The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library. {END}  Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
 **
-** {F17341} The [sqlite3_release_memory(N)] interface attempts to
-**          free N bytes of heap memory by deallocating non-essential
-**          memory allocations held by the database labrary.
-**
-** {F16342} The [sqlite3_release_memory(N)] returns the number
-**          of bytes actually freed, which might be more or less
-**          than the amount requested.
+** Requirements: [H17341] [H17342]
 */
-int sqlite3_release_memory(int);
+SQLITE_API int sqlite3_release_memory(int);
 
 /*
-** CAPI3REF:  Impose A Limit On Heap Size {F17350}
+** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
 **
-** The sqlite3_soft_heap_limit() interface
-** places a "soft" limit on the amount of heap memory that may be allocated
-** by SQLite. If an internal allocation is requested 
-** that would exceed the soft heap limit, [sqlite3_release_memory()] is
-** invoked one or more times to free up some space before the allocation
-** is made.
+** The sqlite3_soft_heap_limit() interface places a "soft" limit
+** on the amount of heap memory that may be allocated by SQLite.
+** If an internal allocation is requested that would exceed the
+** soft heap limit, [sqlite3_release_memory()] is invoked one or
+** more times to free up some space before the allocation is performed.
 **
-** The limit is called "soft", because if
-** [sqlite3_release_memory()] cannot
-** free sufficient memory to prevent the limit from being exceeded,
+** The limit is called "soft", because if [sqlite3_release_memory()]
+** cannot free sufficient memory to prevent the limit from being exceeded,
 ** the memory is allocated anyway and the current operation proceeds.
 **
 ** A negative or zero value for N means that there is no soft heap limit and
 ** [sqlite3_release_memory()] will only be called when memory is exhausted.
 ** The default value for the soft heap limit is zero.
 **
-** SQLite makes a best effort to honor the soft heap limit.  
-** But if the soft heap limit cannot honored, execution will
-** continue without error or notification.  This is why the limit is 
+** SQLite makes a best effort to honor the soft heap limit.
+** But if the soft heap limit cannot be honored, execution will
+** continue without error or notification.  This is why the limit is
 ** called a "soft" limit.  It is advisory only.
 **
 ** Prior to SQLite version 3.5.0, this routine only constrained the memory
@@ -4655,83 +4029,56 @@ int sqlite3_release_memory(int);
 ** version 3.5.0 there is no mechanism for limiting the heap usage for
 ** individual threads.
 **
-** INVARIANTS:
-**
-** {F16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
-**          of N bytes on the amount of heap memory that may be allocated
-**          using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
-**          in time.
-**
-** {F16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
-**          cause the total amount of allocated memory to exceed the
-**          soft heap limit, then [sqlite3_release_memory()] is invoked
-**          in an attempt to reduce the memory usage prior to proceeding
-**          with the memory allocation attempt.
-**
-** {F16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
-**          attempts to reduce memory usage through the soft heap limit
-**          mechanism continue even if the attempt to reduce memory
-**          usage is unsuccessful.
-**
-** {F16354} A negative or zero value for N in a call to
-**          [sqlite3_soft_heap_limit(N)] means that there is no soft
-**          heap limit and [sqlite3_release_memory()] will only be
-**          called when memory is completely exhausted.
-**
-** {F16355} The default value for the soft heap limit is zero.
-**
-** {F16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
-**          values set by all prior calls.
+** Requirements:
+** [H16351] [H16352] [H16353] [H16354] [H16355] [H16358]
 */
-void sqlite3_soft_heap_limit(int);
+SQLITE_API void sqlite3_soft_heap_limit(int);
 
 /*
-** CAPI3REF:  Extract Metadata About A Column Of A Table {F12850}
+** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
 **
-** This routine
-** returns meta-data about a specific column of a specific database
-** table accessible using the connection handle passed as the first function 
-** argument.
+** This routine returns metadata about a specific column of a specific
+** database table accessible using the [database connection] handle
+** passed as the first function argument.
 **
-** The column is identified by the second, third and fourth parameters to 
+** The column is identified by the second, third and fourth parameters to
 ** this function. The second parameter is either the name of the database
 ** (i.e. "main", "temp" or an attached database) containing the specified
 ** table or NULL. If it is NULL, then all attached databases are searched
-** for the table using the same algorithm as the database engine uses to 
+** for the table using the same algorithm used by the database engine to
 ** resolve unqualified table references.
 **
-** The third and fourth parameters to this function are the table and column 
-** name of the desired column, respectively. Neither of these parameters 
+** The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively. Neither of these parameters
 ** may be NULL.
 **
-** Meta information is returned by writing to the memory locations passed as
-** the 5th and subsequent parameters to this function. Any of these 
-** arguments may be NULL, in which case the corresponding element of meta 
-** information is ommitted.
+** Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
 **
-** <pre>
-** Parameter     Output Type      Description
-** -----------------------------------
-**
-**   5th         const char*      Data type
-**   6th         const char*      Name of the default collation sequence 
-**   7th         int              True if the column has a NOT NULL constraint
-**   8th         int              True if the column is part of the PRIMARY KEY
-**   9th         int              True if the column is AUTOINCREMENT
-** </pre>
+** <blockquote>
+** <table border="1">
+** <tr><th> Parameter <th> Output<br>Type <th>  Description
 **
+** <tr><td> 5th <td> const char* <td> Data type
+** <tr><td> 6th <td> const char* <td> Name of default collation sequence
+** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
+** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
+** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
+** </table>
+** </blockquote>
 **
-** The memory pointed to by the character pointers returned for the 
-** declaration type and collation sequence is valid only until the next 
-** call to any sqlite API function.
+** The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid only until the next
+** call to any SQLite API function.
 **
-** If the specified table is actually a view, then an error is returned.
+** If the specified table is actually a view, an [error code] is returned.
 **
-** If the specified column is "rowid", "oid" or "_rowid_" and an 
-** INTEGER PRIMARY KEY column has been explicitly declared, then the output 
+** If the specified column is "rowid", "oid" or "_rowid_" and an
+** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
 ** parameters are set for the explicitly declared column. If there is no
-** explicitly declared IPK column, then the output parameters are set as 
-** follows:
+** explicitly declared [INTEGER PRIMARY KEY] column, then the output
+** parameters are set as follows:
 **
 ** <pre>
 **     data type: "INTEGER"
@@ -4743,13 +4090,13 @@ void sqlite3_soft_heap_limit(int);
 **
 ** This function may load one or more schemas from database files. If an
 ** error occurs during this process, or if the requested table or column
-** cannot be found, an SQLITE error code is returned and an error message
-** left in the database handle (to be retrieved using sqlite3_errmsg()).
+** cannot be found, an [error code] is returned and an error message left
+** in the [database connection] (to be retrieved using sqlite3_errmsg()).
 **
 ** This API is only available if the library was compiled with the
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 */
-int sqlite3_table_column_metadata(
+SQLITE_API int sqlite3_table_column_metadata(
   sqlite3 *db,                /* Connection handle */
   const char *zDbName,        /* Database name or NULL */
   const char *zTableName,     /* Table name */
@@ -4762,29 +4109,32 @@ int sqlite3_table_column_metadata(
 );
 
 /*
-** CAPI3REF: Load An Extension {F12600}
+** CAPI3REF: Load An Extension {H12600} <S20500>
+**
+** This interface loads an SQLite extension library from the named file.
+**
+** {H12601} The sqlite3_load_extension() interface attempts to load an
+**          SQLite extension library contained in the file zFile.
 **
-** {F12601} The sqlite3_load_extension() interface
-** attempts to load an SQLite extension library contained in the file
-** zFile. {F12602} The entry point is zProc. {F12603} zProc may be 0
-** in which case the name of the entry point defaults
-** to "sqlite3_extension_init".
+** {H12602} The entry point is zProc.
 **
-** {F12604} The sqlite3_load_extension() interface shall
-** return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** {H12603} zProc may be 0, in which case the name of the entry point
+**          defaults to "sqlite3_extension_init".
 **
-** {F12605}
-** If an error occurs and pzErrMsg is not 0, then the
-** sqlite3_load_extension() interface shall attempt to fill *pzErrMsg with 
-** error message text stored in memory obtained from [sqlite3_malloc()].
-** {END}  The calling function should free this memory
-** by calling [sqlite3_free()].
+** {H12604} The sqlite3_load_extension() interface shall return
+**          [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
 **
-** {F12606}
-** Extension loading must be enabled using [sqlite3_enable_load_extension()]
-** prior to calling this API or an error will be returned.
+** {H12605} If an error occurs and pzErrMsg is not 0, then the
+**          [sqlite3_load_extension()] interface shall attempt to
+**          fill *pzErrMsg with error message text stored in memory
+**          obtained from [sqlite3_malloc()]. {END}  The calling function
+**          should free this memory by calling [sqlite3_free()].
+**
+** {H12606} Extension loading must be enabled using
+**          [sqlite3_enable_load_extension()] prior to calling this API,
+**          otherwise an error will be returned.
 */
-int sqlite3_load_extension(
+SQLITE_API int sqlite3_load_extension(
   sqlite3 *db,          /* Load the extension into this database connection */
   const char *zFile,    /* Name of the shared library containing extension */
   const char *zProc,    /* Entry point.  Derived from zFile if 0 */
@@ -4792,64 +4142,63 @@ int sqlite3_load_extension(
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Extension Loading {F12620}
+** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
 **
 ** So as not to open security holes in older applications that are
 ** unprepared to deal with extension loading, and as a means of disabling
-** extension loading while evaluating user-entered SQL, the following
-** API is provided to turn the [sqlite3_load_extension()] mechanism on and
-** off.  {F12622} It is off by default. {END} See ticket #1863.
+** extension loading while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
+**
+** Extension loading is off by default. See ticket #1863.
 **
-** {F12621} Call the sqlite3_enable_load_extension() routine
-** with onoff==1 to turn extension loading on
-** and call it with onoff==0 to turn it back off again. {END}
+** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
+**          to turn extension loading on and call it with onoff==0 to turn
+**          it back off again.
+**
+** {H12622} Extension loading is off by default.
 */
-int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
+SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Make Arrangements To Automatically Load An Extension {F12640}
-**
-** {F12641} This function
-** registers an extension entry point that is automatically invoked
-** whenever a new database connection is opened using
-** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()]. {END}
+** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
 **
 ** This API can be invoked at program startup in order to register
 ** one or more statically linked extensions that will be available
-** to all new database connections.
+** to all new [database connections]. {END}
 **
-** {F12642} Duplicate extensions are detected so calling this routine multiple
-** times with the same extension is harmless.
+** This routine stores a pointer to the extension in an array that is
+** obtained from [sqlite3_malloc()].  If you run a memory leak checker
+** on your program and it reports a leak because of this array, invoke
+** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
 **
-** {F12643} This routine stores a pointer to the extension in an array
-** that is obtained from sqlite_malloc(). {END} If you run a memory leak
-** checker on your program and it reports a leak because of this
-** array, then invoke [sqlite3_reset_auto_extension()] prior
-** to shutdown to free the memory.
+** {H12641} This function registers an extension entry point that is
+**          automatically invoked whenever a new [database connection]
+**          is opened using [sqlite3_open()], [sqlite3_open16()],
+**          or [sqlite3_open_v2()].
 **
-** {F12644} Automatic extensions apply across all threads. {END}
+** {H12642} Duplicate extensions are detected so calling this routine
+**          multiple times with the same extension is harmless.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12643} This routine stores a pointer to the extension in an array
+**          that is obtained from [sqlite3_malloc()].
+**
+** {H12644} Automatic extensions apply across all threads.
 */
-int sqlite3_auto_extension(void *xEntryPoint);
-
+SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
 /*
-** CAPI3REF: Reset Automatic Extension Loading {F12660}
+** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
 **
-** {F12661} This function disables all previously registered
-** automatic extensions. {END}  This
-** routine undoes the effect of all prior [sqlite3_auto_extension()]
-** calls.
+** This function disables all previously registered automatic
+** extensions. {END}  It undoes the effect of all prior
+** [sqlite3_auto_extension()] calls.
 **
-** {F12662} This call disabled automatic extensions in all threads. {END}
+** {H12661} This function disables all previously registered
+**          automatic extensions.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12662} This function disables automatic extensions in all threads.
 */
-void sqlite3_reset_auto_extension(void);
-
+SQLITE_API void sqlite3_reset_auto_extension(void);
 
 /*
 ****** EXPERIMENTAL - subject to change without notice **************
@@ -4858,7 +4207,7 @@ void sqlite3_reset_auto_extension(void);
 ** to be experimental.  The interface might change in incompatible ways.
 ** If this is a problem for you, do not use the interface at this time.
 **
-** When the virtual-table mechanism stablizes, we will declare the
+** When the virtual-table mechanism stabilizes, we will declare the
 ** interface fixed, support it indefinitely, and remove this comment.
 */
 
@@ -4871,12 +4220,21 @@ typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
 
 /*
-** CAPI3REF: Virtual Table Object {F18000}
-** KEYWORDS: sqlite3_module
-**
-** A module is a class of virtual tables.  Each module is defined
-** by an instance of the following structure.  This structure consists
-** mostly of methods for the module.
+** CAPI3REF: Virtual Table Object {H18000} <S20400>
+** KEYWORDS: sqlite3_module {virtual table module}
+** EXPERIMENTAL
+**
+** This structure, sometimes called a a "virtual table module", 
+** defines the implementation of a [virtual tables].  
+** This structure consists mostly of methods for the module.
+**
+** A virtual table module is created by filling in a persistent
+** instance of this structure and passing a pointer to that instance
+** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
+** The registration remains valid until it is replaced by a different
+** module or until the [database connection] closes.  The content
+** of this structure must not change while it is registered with
+** any database connection.
 */
 struct sqlite3_module {
   int iVersion;
@@ -4905,28 +4263,26 @@ struct sqlite3_module {
   int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
                        void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                        void **ppArg);
-
   int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
 };
 
 /*
-** CAPI3REF: Virtual Table Indexing Information {F18100}
+** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
 ** KEYWORDS: sqlite3_index_info
+** EXPERIMENTAL
 **
 ** The sqlite3_index_info structure and its substructures is used to
-** pass information into and receive the reply from the xBestIndex
-** method of an sqlite3_module.  The fields under **Inputs** are the
+** pass information into and receive the reply from the [xBestIndex]
+** method of a [virtual table module].  The fields under **Inputs** are the
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
 ** results into the **Outputs** fields.
 **
-** The aConstraint[] array records WHERE clause constraints of the
-** form:
+** The aConstraint[] array records WHERE clause constraints of the form:
 **
-**         column OP expr
+** <pre>column OP expr</pre>
 **
-** Where OP is =, &lt;, &lt;=, &gt;, or &gt;=.  
-** The particular operator is stored
-** in aConstraint[].op.  The index of the column is stored in 
+** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.  The particular operator is
+** stored in aConstraint[].op.  The index of the column is stored in
 ** aConstraint[].iColumn.  aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.
@@ -4940,17 +4296,19 @@ struct sqlite3_module {
 ** Information about the ORDER BY clause is stored in aOrderBy[].
 ** Each term of aOrderBy records a column of the ORDER BY clause.
 **
-** The xBestIndex method must fill aConstraintUsage[] with information
+** The [xBestIndex] method must fill aConstraintUsage[] with information
 ** about what parameters to pass to xFilter.  If argvIndex>0 then
 ** the right-hand side of the corresponding aConstraint[] is evaluated
 ** and becomes the argvIndex-th entry in argv.  If aConstraintUsage[].omit
 ** is true, then the constraint is assumed to be fully handled by the
 ** virtual table and is not checked again by SQLite.
 **
-** The idxNum and idxPtr values are recorded and passed into xFilter.
-** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
+** The idxNum and idxPtr values are recorded and passed into the
+** [xFilter] method.
+** [sqlite3_free()] is used to free idxPtr if and only iff
+** needToFreeIdxPtr is true.
 **
-** The orderByConsumed means that output from xFilter will occur in
+** The orderByConsumed means that output from [xFilter]/[xNext] will occur in
 ** the correct order to satisfy the ORDER BY clause so that no separate
 ** sorting step is required.
 **
@@ -4973,7 +4331,6 @@ struct sqlite3_index_info {
      int iColumn;              /* Column number */
      unsigned char desc;       /* True for DESC.  False for ASC. */
   } *aOrderBy;               /* The ORDER BY clause */
-
   /* Outputs */
   struct sqlite3_index_constraint_usage {
     int argvIndex;           /* if >0, constraint is part of argv to xFilter */
@@ -4993,70 +4350,89 @@ struct sqlite3_index_info {
 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18200}
-**
-** This routine is used to register a new module name with an SQLite
-** connection.  Module names must be registered before creating new
-** virtual tables on the module, or before using preexisting virtual
-** tables of the module.
+** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
+** EXPERIMENTAL
+**
+** This routine is used to register a new [virtual table module] name.
+** Module names must be registered before
+** creating a new [virtual table] using the module, or before using a
+** preexisting [virtual table] for the module.
+**
+** The module name is registered on the [database connection] specified
+** by the first parameter.  The name of the module is given by the 
+** second parameter.  The third parameter is a pointer to
+** the implementation of the [virtual table module].   The fourth
+** parameter is an arbitrary client data pointer that is passed through
+** into the [xCreate] and [xConnect] methods of the virtual table module
+** when a new virtual table is be being created or reinitialized.
+**
+** This interface has exactly the same effect as calling
+** [sqlite3_create_module_v2()] with a NULL client data destructor.
 */
-int sqlite3_create_module(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
-  const sqlite3_module *,    /* Methods for the module */
-  void *                     /* Client data for xCreate/xConnect */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData          /* Client data for xCreate/xConnect */
 );
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18210}
-**
-** This routine is identical to the sqlite3_create_module() method above,
-** except that it allows a destructor function to be specified. It is
-** even more experimental than the rest of the virtual tables API.
+** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
+** EXPERIMENTAL
+**
+** This routine is identical to the [sqlite3_create_module()] method,
+** except that it has an extra parameter to specify 
+** a destructor function for the client data pointer.  SQLite will
+** invoke the destructor function (if it is not NULL) when SQLite
+** no longer needs the pClientData pointer.  
 */
-int sqlite3_create_module_v2(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
-  const sqlite3_module *,    /* Methods for the module */
-  void *,                    /* Client data for xCreate/xConnect */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData,         /* Client data for xCreate/xConnect */
   void(*xDestroy)(void*)     /* Module destructor function */
 );
 
 /*
-** CAPI3REF: Virtual Table Instance Object {F18010}
+** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
 ** KEYWORDS: sqlite3_vtab
+** EXPERIMENTAL
 **
-** Every module implementation uses a subclass of the following structure
-** to describe a particular instance of the module.  Each subclass will
-** be tailored to the specific needs of the module implementation.   The
-** purpose of this superclass is to define certain fields that are common
-** to all module implementations.
+** Every [virtual table module] implementation uses a subclass
+** of the following structure to describe a particular instance
+** of the [virtual table].  Each subclass will
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
 **
 ** Virtual tables methods can set an error message by assigning a
-** string obtained from sqlite3_mprintf() to zErrMsg.  The method should
-** take care that any prior string is freed by a call to sqlite3_free()
+** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
 ** prior to assigning a new string to zErrMsg.  After the error message
 ** is delivered up to the client application, the string will be automatically
-** freed by sqlite3_free() and the zErrMsg field will be zeroed.  Note
-** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
-** since virtual tables are commonly implemented in loadable extensions which
-** do not have access to sqlite3MPrintf() or sqlite3Free().
+** freed by sqlite3_free() and the zErrMsg field will be zeroed.
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;  /* The module for this virtual table */
-  int nRef;                       /* Used internally */
+  int nRef;                       /* NO LONGER USED */
   char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
   /* Virtual table implementations will typically add additional fields */
 };
 
 /*
-** CAPI3REF: Virtual Table Cursor Object  {F18020}
-** KEYWORDS: sqlite3_vtab_cursor
+** CAPI3REF: Virtual Table Cursor Object  {H18020} <S20400>
+** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
+** EXPERIMENTAL
 **
-** Every module implementation uses a subclass of the following structure
-** to describe cursors that point into the virtual table and are used
+** Every [virtual table module] implementation uses a subclass of the
+** following structure to describe cursors that point into the
+** [virtual table] and are used
 ** to loop through the virtual table.  Cursors are created using the
-** xOpen method of the module.  Each module implementation will define
+** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
+** by the [sqlite3_module.xClose | xClose] method.  Cussors are used
+** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
+** of the module.  Each module implementation will define
 ** the content of a cursor structure to suit its own needs.
 **
 ** This superclass exists in order to define fields of the cursor that
@@ -5068,19 +4444,23 @@ struct sqlite3_vtab_cursor {
 };
 
 /*
-** CAPI3REF: Declare The Schema Of A Virtual Table {F18280}
+** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
+** EXPERIMENTAL
 **
-** The xCreate and xConnect methods of a module use the following API
+** The [xCreate] and [xConnect] methods of a
+** [virtual table module] call this interface
 ** to declare the format (the names and datatypes of the columns) of
 ** the virtual tables they implement.
 */
-int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
 
 /*
-** CAPI3REF: Overload A Function For A Virtual Table {F18300}
+** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
+** EXPERIMENTAL
 **
 ** Virtual tables can provide alternative implementations of functions
-** using the xFindFunction method.  But global versions of those functions
+** using the [xFindFunction] method of the [virtual table module].  
+** But global versions of those functions
 ** must exist in order to be overloaded.
 **
 ** This API makes sure a global version of a function with a particular
@@ -5088,13 +4468,10 @@ int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
 ** before this API is called, a new function is created.  The implementation
 ** of the new function always causes an exception to be thrown.  So
 ** the new function is not good for anything by itself.  Its only
-** purpose is to be a place-holder function that can be overloaded
-** by virtual tables.
-**
-** This API should be considered part of the virtual table interface,
-** which is experimental and subject to change.
+** purpose is to be a placeholder function that can be overloaded
+** by a [virtual table].
 */
-int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
 
 /*
 ** The interface to the virtual-table mechanism defined above (back up
@@ -5109,70 +4486,79 @@ int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
 */
 
 /*
-** CAPI3REF: A Handle To An Open BLOB {F17800}
+** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
+** KEYWORDS: {BLOB handle} {BLOB handles}
 **
 ** An instance of this object represents an open BLOB on which
-** incremental I/O can be preformed.
-** Objects of this type are created by
-** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
 ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
-** can be used to read or write small subsections of the blob.
-** The [sqlite3_blob_bytes()] interface returns the size of the
-** blob in bytes.
+** can be used to read or write small subsections of the BLOB.
+** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
 */
 typedef struct sqlite3_blob sqlite3_blob;
 
 /*
-** CAPI3REF: Open A BLOB For Incremental I/O {F17810}
+** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
 **
-** This interfaces opens a handle to the blob located
+** This interfaces opens a [BLOB handle | handle] to the BLOB located
 ** in row iRow, column zColumn, table zTable in database zDb;
-** in other words,  the same blob that would be selected by:
+** in other words, the same BLOB that would be selected by:
 **
 ** <pre>
-**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
+**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
 ** </pre> {END}
 **
-** If the flags parameter is non-zero, the blob is opened for 
-** read and write access. If it is zero, the blob is opened for read 
-** access.
+** If the flags parameter is non-zero, then the BLOB is opened for read
+** and write access. If it is zero, the BLOB is opened for read access.
+** It is not possible to open a column that is part of an index or primary 
+** key for writing. ^If [foreign key constraints] are enabled, it is 
+** not possible to open a column that is part of a [child key] for writing.
 **
 ** Note that the database name is not the filename that contains
 ** the database but rather the symbolic name of the database that
 ** is assigned when the database is connected using [ATTACH].
-** For the main database file, the database name is "main".  For
-** TEMP tables, the database name is "temp".
-**
-** On success, [SQLITE_OK] is returned and the new 
-** [sqlite3_blob | blob handle] is written to *ppBlob. 
-** Otherwise an error code is returned and 
-** any value written to *ppBlob should not be used by the caller.
-** This function sets the database-handle error code and message
-** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
-** 
-** INVARIANTS:
-**
-** {F17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
-**          interface opens an [sqlite3_blob] object P on the blob
-**          in column C of table T in database B on [database connection] D.
-**
-** {F17814} A successful invocation of [sqlite3_blob_open(D,...)] starts
-**          a new transaction on [database connection] D if that connection
-**          is not already in a transaction.
-**
-** {F17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface opens the blob
-**          for read and write access if and only if the F parameter
-**          is non-zero.
-**
-** {F17819} The [sqlite3_blob_open()] interface returns [SQLITE_OK] on 
-**          success and an appropriate [error code] on failure.
-**
-** {F17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+** For the main database file, the database name is "main".
+** For TEMP tables, the database name is "temp".
+**
+** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
+** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
+** to be a null pointer.
+** This function sets the [database connection] error code and message
+** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
+** functions.  Note that the *ppBlob variable is always initialized in a
+** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
+** regardless of the success or failure of this routine.
+**
+** If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.
+** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
+** Changes written into a BLOB prior to the BLOB expiring are not
+** rollback by the expiration of the BLOB.  Such changes will eventually
+** commit if the transaction continues to completion.
+**
+** Use the [sqlite3_blob_bytes()] interface to determine the size of
+** the opened blob.  The size of a blob may not be changed by this
+** interface.  Use the [UPDATE] SQL command to change the size of a
+** blob.
+**
+** The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
+** and the built-in [zeroblob] SQL function can be used, if desired,
+** to create an empty, zero-filled blob in which to read or write using
+** this interface.
+**
+** To avoid a resource leak, every open [BLOB handle] should eventually
+** be released by a call to [sqlite3_blob_close()].
+**
+** Requirements:
+** [H17813] [H17814] [H17816] [H17819] [H17821] [H17824]
 */
-int sqlite3_blob_open(
+SQLITE_API int sqlite3_blob_open(
   sqlite3*,
   const char *zDb,
   const char *zTable,
@@ -5183,158 +4569,125 @@ int sqlite3_blob_open(
 );
 
 /*
-** CAPI3REF:  Close A BLOB Handle {F17830}
+** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
 **
-** Close an open [sqlite3_blob | blob handle].
+** Closes an open [BLOB handle].
 **
 ** Closing a BLOB shall cause the current transaction to commit
 ** if there are no other BLOBs, no pending prepared statements, and the
-** database connection is in autocommit mode.
+** database connection is in [autocommit mode].
 ** If any writes were made to the BLOB, they might be held in cache
-** until the close operation if they will fit. {END}
+** until the close operation if they will fit.
+**
 ** Closing the BLOB often forces the changes
 ** out to disk and so if any I/O errors occur, they will likely occur
-** at the time when the BLOB is closed.  {F17833} Any errors that occur during
+** at the time when the BLOB is closed.  Any errors that occur during
 ** closing are reported as a non-zero return value.
 **
 ** The BLOB is closed unconditionally.  Even if this routine returns
 ** an error code, the BLOB is still closed.
 **
-** INVARIANTS:
-**
-** {F17833} The [sqlite3_blob_close(P)] interface closes an
-**          [sqlite3_blob] object P previously opened using
-**          [sqlite3_blob_open()].
-**
-** {F17836} Closing an [sqlite3_blob] object using
-**          [sqlite3_blob_close()] shall cause the current transaction to
-**          commit if there are no other open [sqlite3_blob] objects
-**          or [prepared statements] on the same [database connection] and
-**          the [database connection] is in
-**          [sqlite3_get_autocommit | autocommit mode].
+** Calling this routine with a null pointer (which as would be returned
+** by failed call to [sqlite3_blob_open()]) is a harmless no-op.
 **
-** {F17839} The [sqlite3_blob_close(P)] interfaces closes the 
-**          [sqlite3_blob] object P unconditionally, even if
-**          [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
-**          
+** Requirements:
+** [H17833] [H17836] [H17839]
 */
-int sqlite3_blob_close(sqlite3_blob *);
+SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Return The Size Of An Open BLOB {F17840}
+** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
 **
-** Return the size in bytes of the blob accessible via the open 
-** [sqlite3_blob] object in its only argument.
+** Returns the size in bytes of the BLOB accessible via the 
+** successfully opened [BLOB handle] in its only argument.  The
+** incremental blob I/O routines can only read or overwriting existing
+** blob content; they cannot change the size of a blob.
 **
-** INVARIANTS:
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17843} The [sqlite3_blob_bytes(P)] interface returns the size
-**          in bytes of the BLOB that the [sqlite3_blob] object P
-**          refers to.
+** Requirements:
+** [H17843]
 */
-int sqlite3_blob_bytes(sqlite3_blob *);
+SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Read Data From A BLOB Incrementally {F17850}
+** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
 **
-** This function is used to read data from an open 
-** [sqlite3_blob | blob-handle] into a caller supplied buffer.
-** N bytes of data are copied into buffer
-** Z from the open blob, starting at offset iOffset.
+** This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.
 **
-** If offset iOffset is less than N bytes from the end of the blob, 
+** If offset iOffset is less than N bytes from the end of the BLOB,
 ** [SQLITE_ERROR] is returned and no data is read.  If N or iOffset is
-** less than zero [SQLITE_ERROR] is returned and no data is read.
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
+** The size of the blob (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
+** An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
 **
-** INVARIANTS:
+** On success, SQLITE_OK is returned.
+** Otherwise, an [error code] or an [extended error code] is returned.
 **
-** {F17853} The [sqlite3_blob_read(P,Z,N,X)] interface reads N bytes
-**          beginning at offset X from
-**          the blob that [sqlite3_blob] object P refers to
-**          and writes those N bytes into buffer Z.
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
+** See also: [sqlite3_blob_write()].
 **
-** {F17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
-**
-** {F17862} The [sqlite3_blob_read(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully read into buffer Z.
-**
-** {F17865} If the requested read could not be completed,
-**          the [sqlite3_blob_read(P,Z,N,X)] interface returns an
-**          appropriate [error code] or [extended error code].
-**
-** {F17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error, where D is the
-**          database handle that was used to open blob handle P.
+** Requirements:
+** [H17853] [H17856] [H17859] [H17862] [H17863] [H17865] [H17868]
 */
-int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
+SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
 
 /*
-** CAPI3REF:  Write Data Into A BLOB Incrementally {F17870}
+** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
 **
-** This function is used to write data into an open 
-** [sqlite3_blob | blob-handle] from a user supplied buffer.
-** n bytes of data are copied from the buffer
-** pointed to by z into the open blob, starting at offset iOffset.
+** This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.
 **
-** If the [sqlite3_blob | blob-handle] passed as the first argument
-** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
-*** was zero), this function returns [SQLITE_READONLY].
+** If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
 **
-** This function may only modify the contents of the blob; it is
-** not possible to increase the size of a blob using this API.
-** If offset iOffset is less than n bytes from the end of the blob, 
-** [SQLITE_ERROR] is returned and no data is written.  If n is
+** This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written.  If N is
 ** less than zero [SQLITE_ERROR] is returned and no data is written.
+** The size of the BLOB (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
-**
-** INVARIANTS:
-**
-** {F17873} The [sqlite3_blob_write(P,Z,N,X)] interface writes N bytes
-**          from buffer Z into
-**          the blob that [sqlite3_blob] object P refers to
-**          beginning at an offset of X into the blob.
+** An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].  Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
 **
-** {F17875} The [sqlite3_blob_write(P,Z,N,X)] interface returns
-**          [SQLITE_READONLY] if the [sqlite3_blob] object P was
-**          [sqlite3_blob_open | opened] for reading only.
+** On success, SQLITE_OK is returned.
+** Otherwise, an  [error code] or an [extended error code] is returned.
 **
-** {F17876} In [sqlite3_blob_write(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
 **
-** {F17879} In [sqlite3_blob_write(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** See also: [sqlite3_blob_read()].
 **
-** {F17882} The [sqlite3_blob_write(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully written into blob.
-**
-** {F17885} If the requested write could not be completed,
-**          the [sqlite3_blob_write(P,Z,N,X)] interface returns an
-**          appropriate [error code] or [extended error code].
-**
-** {F17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
-**          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+** Requirements:
+** [H17873] [H17874] [H17875] [H17876] [H17877] [H17879] [H17882] [H17885]
+** [H17888]
 */
-int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
+SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
 
 /*
-** CAPI3REF:  Virtual File System Objects {F11200}
+** CAPI3REF: Virtual File System Objects {H11200} <S20100>
 **
 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
 ** that SQLite uses to interact
@@ -5343,12 +4696,11 @@ int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
 ** New VFSes can be registered and existing VFSes can be unregistered.
 ** The following interfaces are provided.
 **
-** The sqlite3_vfs_find() interface returns a pointer to 
-** a VFS given its name.  Names are case sensitive.
+** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** Names are case sensitive.
 ** Names are zero-terminated UTF-8 strings.
-** If there is no match, a NULL
-** pointer is returned.  If zVfsName is NULL then the default 
-** VFS is returned. 
+** If there is no match, a NULL pointer is returned.
+** If zVfsName is NULL then the default VFS is returned.
 **
 ** New VFSes are registered with sqlite3_vfs_register().
 ** Each new VFS becomes the default VFS if the makeDflt flag is set.
@@ -5358,51 +4710,27 @@ int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
 ** same name are registered, the behavior is undefined.  If a
 ** VFS is registered with a name that is NULL or an empty string,
 ** then the behavior is undefined.
-** 
+**
 ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
 ** If the default VFS is unregistered, another VFS is chosen as
 ** the default.  The choice for the new VFS is arbitrary.
 **
-** INVARIANTS:
-**
-** {F11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
-**          registered [sqlite3_vfs] object whose name exactly matches
-**          the zero-terminated UTF-8 string N, or it returns NULL if
-**          there is no match.
-**
-** {F11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
-**          the function returns a pointer to the default [sqlite3_vfs]
-**          object if there is one, or NULL if there is no default 
-**          [sqlite3_vfs] object.
-**
-** {F11209} The [sqlite3_vfs_register(P,F)] interface registers the
-**          well-formed [sqlite3_vfs] object P using the name given
-**          by the zName field of the object.
-**
-** {F11212} Using the [sqlite3_vfs_register(P,F)] interface to register
-**          the same [sqlite3_vfs] object multiple times is a harmless no-op.
-**
-** {F11215} The [sqlite3_vfs_register(P,F)] interface makes the
-**          the [sqlite3_vfs] object P the default [sqlite3_vfs] object
-**          if F is non-zero.
-**
-** {F11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
-**          [sqlite3_vfs] object P so that it is no longer returned by
-**          subsequent calls to [sqlite3_vfs_find()].
+** Requirements:
+** [H11203] [H11206] [H11209] [H11212] [H11215] [H11218]
 */
-sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
-int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
-int sqlite3_vfs_unregister(sqlite3_vfs*);
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 
 /*
-** CAPI3REF: Mutexes {F17000}
+** CAPI3REF: Mutexes {H17000} <S20000>
 **
 ** The SQLite core uses these routines for thread
-** synchronization.  Though they are intended for internal
+** synchronization. Though they are intended for internal
 ** use by SQLite, code that links against SQLite is
 ** permitted to use any of these routines.
 **
-** The SQLite source code contains multiple implementations 
+** The SQLite source code contains multiple implementations
 ** of these mutex routines.  An appropriate implementation
 ** is selected automatically at compile-time.  The following
 ** implementations are available in the SQLite core:
@@ -5414,25 +4742,24 @@ int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** <li>   SQLITE_MUTEX_NOOP
 ** </ul>
 **
-** The SQLITE_MUTEX_NOOP implementation is a set of routines 
-** that does no real locking and is appropriate for use in 
+** The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
 ** a single-threaded application.  The SQLITE_MUTEX_OS2,
 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
-** are appropriate for use on os/2, unix, and windows.
-** 
+** are appropriate for use on OS/2, Unix, and Windows.
+**
 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
-** implementation is included with the library.  The
-** mutex interface routines defined here become external
-** references in the SQLite library for which implementations
-** must be provided by the application.  This facility allows an
-** application that links against SQLite to provide its own mutex
-** implementation without having to modify the SQLite core.
-**
-** {F17011} The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it. {F17012} If it returns NULL
-** that means that a mutex could not be allocated. {F17013} SQLite
-** will unwind its stack and return an error. {F17014} The argument
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().
+**
+** {H17011} The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. {H17012} If it returns NULL
+** that means that a mutex could not be allocated. {H17013} SQLite
+** will unwind its stack and return an error. {H17014} The argument
 ** to sqlite3_mutex_alloc() is one of these integer constants:
 **
 ** <ul>
@@ -5444,152 +4771,249 @@ int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** <li>  SQLITE_MUTEX_STATIC_PRNG
 ** <li>  SQLITE_MUTEX_STATIC_LRU
 ** <li>  SQLITE_MUTEX_STATIC_LRU2
-** </ul> {END}
+** </ul>
 **
-** {F17015} The first two constants cause sqlite3_mutex_alloc() to create
+** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
 ** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
 ** The mutex implementation does not need to make a distinction
 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  {F17016} But SQLite will only request a recursive mutex in
+** not want to.  {H17016} But SQLite will only request a recursive mutex in
 ** cases where it really needs one.  {END} If a faster non-recursive mutex
 ** implementation is available on the host platform, the mutex subsystem
 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
 **
-** {F17017} The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex. {END}  Four static mutexes are
+** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. {END}  Six static mutexes are
 ** used by the current version of SQLite.  Future versions of SQLite
 ** may add additional static mutexes.  Static mutexes are for internal
 ** use by SQLite only.  Applications that use SQLite mutexes should
 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
 ** SQLITE_MUTEX_RECURSIVE.
 **
-** {F17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  {F17034} But for the static 
+** returns a different mutex on every call.  {H17034} But for the static
 ** mutex types, the same mutex is returned on every call that has
-** the same type number. {END}
+** the same type number.
 **
-** {F17019} The sqlite3_mutex_free() routine deallocates a previously
-** allocated dynamic mutex. {F17020} SQLite is careful to deallocate every
-** dynamic mutex that it allocates. {U17021} The dynamic mutexes must not be in 
-** use when they are deallocated. {U17022} Attempting to deallocate a static
-** mutex results in undefined behavior. {F17023} SQLite never deallocates
+** {H17019} The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
+** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
+** use when they are deallocated. {A17022} Attempting to deallocate a static
+** mutex results in undefined behavior. {H17023} SQLite never deallocates
 ** a static mutex. {END}
 **
 ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex. {F17024} If another thread is already within the mutex,
+** to enter a mutex. {H17024} If another thread is already within the mutex,
 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY. {F17025}  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  {F17026} Mutexes created using
+** SQLITE_BUSY. {H17025}  The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry.  {H17026} Mutexes created using
 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
-** {F17027} In such cases the,
+** {H17027} In such cases the,
 ** mutex must be exited an equal number of times before another thread
-** can enter.  {U17028} If the same thread tries to enter any other
+** can enter.  {A17028} If the same thread tries to enter any other
 ** kind of mutex more than once, the behavior is undefined.
-** {F17029} SQLite will never exhibit
-** such behavior in its own use of mutexes. {END}
+** {H17029} SQLite will never exhibit
+** such behavior in its own use of mutexes.
 **
-** Some systems (ex: windows95) do not the operation implemented by
-** sqlite3_mutex_try().  On those systems, sqlite3_mutex_try() will
-** always return SQLITE_BUSY.  {F17030} The SQLite core only ever uses
-** sqlite3_mutex_try() as an optimization so this is acceptable behavior. {END}
+** Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY.  {H17030} The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
 **
-** {F17031} The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  {U17032} The behavior
+** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread.  {A17032} The behavior
 ** is undefined if the mutex is not currently entered by the
-** calling thread or is not currently allocated.  {F17033} SQLite will
+** calling thread or is not currently allocated.  {H17033} SQLite will
 ** never do either. {END}
 **
+** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
 */
-sqlite3_mutex *sqlite3_mutex_alloc(int);
-void sqlite3_mutex_free(sqlite3_mutex*);
-void sqlite3_mutex_enter(sqlite3_mutex*);
-int sqlite3_mutex_try(sqlite3_mutex*);
-void sqlite3_mutex_leave(sqlite3_mutex*);
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Verifcation Routines {F17080}
+** CAPI3REF: Mutex Methods Object {H17120} <S20130>
+** EXPERIMENTAL
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the user has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the user
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** {H17001} The xMutexInit routine shall be called by SQLite once for each
+** effective call to [sqlite3_initialize()].
+**
+** The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
+** interface shall be invoked once for each call to [sqlite3_shutdown()].
+**
+** The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+** <ul>
+**   <li>  [sqlite3_mutex_alloc()] </li>
+**   <li>  [sqlite3_mutex_free()] </li>
+**   <li>  [sqlite3_mutex_enter()] </li>
+**   <li>  [sqlite3_mutex_try()] </li>
+**   <li>  [sqlite3_mutex_leave()] </li>
+**   <li>  [sqlite3_mutex_held()] </li>
+**   <li>  [sqlite3_mutex_notheld()] </li>
+** </ul>
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+**
+** The xMutexInit() method must be threadsafe.  It must be harmless to
+** invoke xMutexInit() mutiple times within the same process and without
+** intervening calls to xMutexEnd().  Second and subsequent calls to
+** xMutexInit() must be no-ops.
+**
+** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
+** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
+** allocation for a static mutex.  However xMutexAlloc() may use SQLite
+** memory allocation for a fast or recursive mutex.
+**
+** SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
+** called, but only if the prior call to xMutexInit returned SQLITE_OK.
+** If xMutexInit fails in any way, it is expected to clean up after itself
+** prior to returning.
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+  int (*xMutexInit)(void);
+  int (*xMutexEnd)(void);
+  sqlite3_mutex *(*xMutexAlloc)(int);
+  void (*xMutexFree)(sqlite3_mutex *);
+  void (*xMutexEnter)(sqlite3_mutex *);
+  int (*xMutexTry)(sqlite3_mutex *);
+  void (*xMutexLeave)(sqlite3_mutex *);
+  int (*xMutexHeld)(sqlite3_mutex *);
+  int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
 **
 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
-** are intended for use inside assert() statements. {F17081} The SQLite core
+** are intended for use inside assert() statements. {H17081} The SQLite core
 ** never uses these routines except inside an assert() and applications
-** are advised to follow the lead of the core.  {F17082} The core only
+** are advised to follow the lead of the core.  {H17082} The core only
 ** provides implementations for these routines when it is compiled
-** with the SQLITE_DEBUG flag.  {U17087} External mutex implementations
+** with the SQLITE_DEBUG flag.  {A17087} External mutex implementations
 ** are only required to provide these routines if SQLITE_DEBUG is
 ** defined and if NDEBUG is not defined.
 **
-** {F17083} These routines should return true if the mutex in their argument
-** is held or not held, respectively, by the calling thread. {END}
+** {H17083} These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
 **
 ** {X17084} The implementation is not required to provided versions of these
-** routines that actually work.
-** If the implementation does not provide working
-** versions of these routines, it should at least provide stubs
-** that always return true so that one does not get spurious
-** assertion failures. {END}
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
 **
-** {F17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
+** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
 ** the routine should return 1.  {END} This seems counter-intuitive since
 ** clearly the mutex cannot be held if it does not exist.  But the
 ** the reason the mutex does not exist is because the build is not
 ** using mutexes.  And we do not want the assert() containing the
 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
-** the appropriate thing to do.  {F17086} The sqlite3_mutex_notheld() 
+** the appropriate thing to do.  {H17086} The sqlite3_mutex_notheld()
 ** interface should also return 1 when given a NULL pointer.
 */
-int sqlite3_mutex_held(sqlite3_mutex*);
-int sqlite3_mutex_notheld(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Types {F17001}
+** CAPI3REF: Mutex Types {H17001} <H17000>
+**
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
 **
-** {F17002} The [sqlite3_mutex_alloc()] interface takes a single argument
-** which is one of these integer constants. {END}
+** The set of static mutexes may change from one SQLite release to the
+** next.  Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
 */
 #define SQLITE_MUTEX_FAST             0
 #define SQLITE_MUTEX_RECURSIVE        1
 #define SQLITE_MUTEX_STATIC_MASTER    2
 #define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
-#define SQLITE_MUTEX_STATIC_MEM2      4  /* sqlite3_release_memory() */
+#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
+#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
 #define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
 #define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
 #define SQLITE_MUTEX_STATIC_LRU2      7  /* lru page list */
 
 /*
-** CAPI3REF: Low-Level Control Of Database Files {F11300}
+** CAPI3REF: Retrieve the mutex for a database connection {H17002} <H17000>
+**
+** This interface returns a pointer the [sqlite3_mutex] object that 
+** serializes access to the [database connection] given in the argument
+** when the [threading mode] is Serialized.
+** If the [threading mode] is Single-thread or Multi-thread then this
+** routine returns a NULL pointer.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
+
+/*
+** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
 **
-** {F11301} The [sqlite3_file_control()] interface makes a direct call to the
+** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
 ** xFileControl method for the [sqlite3_io_methods] object associated
-** with a particular database identified by the second argument. {F11302} The
+** with a particular database identified by the second argument. {H11302} The
 ** name of the database is the name assigned to the database by the
 ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
-** database. {F11303} To control the main database file, use the name "main"
-** or a NULL pointer. {F11304} The third and fourth parameters to this routine
+** database. {H11303} To control the main database file, use the name "main"
+** or a NULL pointer. {H11304} The third and fourth parameters to this routine
 ** are passed directly through to the second and third parameters of
-** the xFileControl method.  {F11305} The return value of the xFileControl
+** the xFileControl method.  {H11305} The return value of the xFileControl
 ** method becomes the return value of this routine.
 **
-** {F11306} If the second parameter (zDbName) does not match the name of any
-** open database file, then SQLITE_ERROR is returned. {F11307} This error
+** {H11306} If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned. {H11307} This error
 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
-** or [sqlite3_errmsg()]. {U11308} The underlying xFileControl method might
-** also return SQLITE_ERROR.  {U11309} There is no way to distinguish between
+** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
+** also return SQLITE_ERROR.  {A11309} There is no way to distinguish between
 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
 ** xFileControl method. {END}
 **
 ** See also: [SQLITE_FCNTL_LOCKSTATE]
 */
-int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
+SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
 
 /*
-** CAPI3REF: Testing Interface {F11400}
+** CAPI3REF: Testing Interface {H11400} <S30800>
 **
 ** The sqlite3_test_control() interface is used to read out internal
 ** state of SQLite and to inject faults into SQLite for testing
-** purposes.  The first parameter a operation code that determines
+** purposes.  The first parameter is an operation code that determines
 ** the number, meaning, and operation of all subsequent parameters.
 **
 ** This interface is not for use by applications.  It exists solely
@@ -5601,28 +5025,728 @@ int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
 ** Unlike most of the SQLite API, this function is not guaranteed to
 ** operate consistently from one release to the next.
 */
-int sqlite3_test_control(int op, ...);
+SQLITE_API int sqlite3_test_control(int op, ...);
 
 /*
-** CAPI3REF: Testing Interface Operation Codes {F11410}
+** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
 **
 ** These constants are the valid operation code parameters used
 ** as the first argument to [sqlite3_test_control()].
 **
-** These parameters and their meansing are subject to change
+** These parameters and their meanings are subject to change
 ** without notice.  These values are for testing purposes only.
 ** Applications should not use any of these parameters or the
 ** [sqlite3_test_control()] interface.
 */
-#define SQLITE_TESTCTRL_FAULT_CONFIG             1
-#define SQLITE_TESTCTRL_FAULT_FAILURES           2
-#define SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES    3
-#define SQLITE_TESTCTRL_FAULT_PENDING            4
 #define SQLITE_TESTCTRL_PRNG_SAVE                5
 #define SQLITE_TESTCTRL_PRNG_RESTORE             6
 #define SQLITE_TESTCTRL_PRNG_RESET               7
 #define SQLITE_TESTCTRL_BITVEC_TEST              8
+#define SQLITE_TESTCTRL_FAULT_INSTALL            9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
+#define SQLITE_TESTCTRL_PENDING_BYTE            11
+#define SQLITE_TESTCTRL_ASSERT                  12
+#define SQLITE_TESTCTRL_ALWAYS                  13
+#define SQLITE_TESTCTRL_RESERVE                 14
 
+/*
+** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information
+** about the preformance of SQLite, and optionally to reset various
+** highwater marks.  The first argument is an integer code for
+** the specific parameter to measure.  Recognized integer codes
+** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
+** The current value of the parameter is returned into *pCurrent.
+** The highest recorded value is returned in *pHighwater.  If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written. Some parameters do not record the highest
+** value.  For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.
+** Other parameters record only the highwater mark and not the current
+** value.  For these latter parameters nothing is written into *pCurrent.
+**
+** This routine returns SQLITE_OK on success and a non-zero
+** [error code] on failure.
+**
+** This routine is threadsafe but is not atomic.  This routine can be
+** called while other threads are running the same or different SQLite
+** interfaces.  However the values returned in *pCurrent and
+** *pHighwater reflect the status of SQLite at different points in time
+** and it is possible that another thread might change the parameter
+** in between the times when *pCurrent and *pHighwater are written.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+
+
+/*
+** CAPI3REF: Status Parameters {H17250} <H17200>
+** EXPERIMENTAL
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+** <dl>
+** <dt>SQLITE_STATUS_MEMORY_USED</dt>
+** <dd>This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly.  The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library.  Scratch memory
+** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter.  The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
+**
+** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents).  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
+** <dd>This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using 
+** [SQLITE_CONFIG_PAGECACHE].  The
+** value returned is in pages, not in bytes.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of page cache
+** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.</dd>
+**
+** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
+** <dd>This parameter returns the number of allocations used out of the
+** [scratch memory allocator] configured using
+** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
+** in bytes.  Since a single thread may only have one scratch allocation
+** outstanding at time, this parameter also reports the number of threads
+** using scratch memory at the same time.</dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of scratch memory
+** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The values
+** returned include overflows because the requested allocation was too
+** larger (that is, because the requested allocation was larger than the
+** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
+** slots were available.
+** </dd>
+**
+** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [scratch memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>
+**
+** <dt>SQLITE_STATUS_PARSER_STACK</dt>
+** <dd>This parameter records the deepest parser stack.  It is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
+** </dl>
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED          0
+#define SQLITE_STATUS_PAGECACHE_USED       1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
+#define SQLITE_STATUS_SCRATCH_USED         3
+#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
+#define SQLITE_STATUS_MALLOC_SIZE          5
+#define SQLITE_STATUS_PARSER_STACK         6
+#define SQLITE_STATUS_PAGECACHE_SIZE       7
+#define SQLITE_STATUS_SCRATCH_SIZE         8
+
+/*
+** CAPI3REF: Database Connection Status {H17500} <S60200>
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information 
+** about a single [database connection].  The first argument is the
+** database connection object to be interrogated.  The second argument
+** is the parameter to interrogate.  Currently, the only allowed value
+** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
+** Additional options will likely appear in future releases of SQLite.
+**
+** The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr.  If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
+** EXPERIMENTAL
+**
+** These constants are the available integer "verbs" that can be passed as
+** the second argument to the [sqlite3_db_status()] interface.
+**
+** New verbs may be added in future releases of SQLite. Existing verbs
+** might be discontinued. Applications should check the return code from
+** [sqlite3_db_status()] to make sure that the call worked.
+** The [sqlite3_db_status()] interface will return a non-zero error code
+** if a discontinued or unsupported verb is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
+** <dd>This parameter returns the number of lookaside memory slots currently
+** checked out.</dd>
+** </dl>
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
+
+
+/*
+** CAPI3REF: Prepared Statement Status {H17550} <S60200>
+** EXPERIMENTAL
+**
+** Each prepared statement maintains various
+** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
+** of times it has performed specific operations.  These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements.  For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.  
+**
+** This interface is used to retrieve and reset counter values from
+** a [prepared statement].  The first argument is the prepared statement
+** object to be interrogated.  The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
+** to be interrogated. 
+** The current value of the requested counter is returned.
+** If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
+** EXPERIMENTAL
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+** <dl>
+** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
+** <dd>This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan.  Large numbers for this counter
+** may indicate opportunities for performance improvement through 
+** careful use of indices.</dd>
+**
+** <dt>SQLITE_STMTSTATUS_SORT</dt>
+** <dd>This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.</dd>
+**
+** </dl>
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
+#define SQLITE_STMTSTATUS_SORT              2
+
+/*
+** CAPI3REF: Custom Page Cache Object
+** EXPERIMENTAL
+**
+** The sqlite3_pcache type is opaque.  It is implemented by
+** the pluggable module.  The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+** EXPERIMENTAL
+**
+** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
+** register an alternative page cache implementation by passing in an 
+** instance of the sqlite3_pcache_methods structure. The majority of the 
+** heap memory used by SQLite is used by the page cache to cache data read 
+** from, or ready to be written to, the database file. By implementing a 
+** custom page cache using this API, an application can control more 
+** precisely the amount of memory consumed by SQLite, the way in which 
+** that memory is allocated and released, and the policies used to 
+** determine exactly which parts of a database file are cached and for 
+** how long.
+**
+** The contents of the sqlite3_pcache_methods structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config].  Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.
+**
+** The xInit() method is called once for each call to [sqlite3_initialize()]
+** (usually only once during the lifetime of the process). It is passed
+** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set
+** up global structures and mutexes required by the custom page cache 
+** implementation. 
+**
+** The xShutdown() method is called from within [sqlite3_shutdown()], 
+** if the application invokes this API. It can be used to clean up 
+** any outstanding resources before process shutdown, if required.
+**
+** SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe.  The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  All other methods must be threadsafe
+** in multithreaded applications.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** The xCreate() method is used to construct a new cache instance.  SQLite
+** will typically create one cache instance for each open database file,
+** though this is not guaranteed. The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache.  szPage will not be a power of two.  szPage
+** will the page size of the database file that is to be cached plus an
+** increment (here called "R") of about 100 or 200.  SQLite will use the
+** extra R bytes on each page to store metadata about the underlying
+** database page on disk.  The value of R depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** R is constant for a particular build of SQLite.  The second argument to
+** xCreate(), bPurgeable, is true if the cache being created will
+** be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory.  On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** In other words, a cache created with bPurgeable set to false will
+** never contain any unpinned pages.
+**
+** The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command. As with the bPurgeable parameter,
+** the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** The xPagecount() method should return the number of pages currently
+** stored in the cache.
+** 
+** The xFetch() method is used to fetch a page and return a pointer to it. 
+** A 'page', in this context, is a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. The
+** mimimum key value is 1. After it has been retrieved using xFetch, the page 
+** is considered to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation is determined by the value of the
+** createFlag parameter passed to xFetch, according to the following table:
+**
+** <table border=1 width=85% align=center>
+** <tr><th> createFlag <th> Behaviour when page is not already in cache
+** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
+** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
+**                 Otherwise return NULL.
+** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
+**                 NULL if allocating a new page is effectively impossible.
+** </table>
+**
+** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
+** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache. After
+** attempting to unpin pages, the xFetch() method will be invoked again with
+** a createFlag of 2.
+**
+** xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument. If the third parameter, discard, is non-zero,
+** then the page should be evicted from the cache. In this case SQLite 
+** assumes that the next time the page is retrieved from the cache using
+** the xFetch() method, it will be zeroed. If the discard parameter is
+** zero, then the page is considered to be unpinned. The cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache is not required to perform any reference counting. A single 
+** call to xUnpin() unpins the page regardless of the number of prior calls 
+** to xFetch().
+**
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument from oldKey to newKey. If the cache
+** previously contains an entry associated with newKey, it should be
+** discarded. Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods
+** functions.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+  void *pArg;
+  int (*xInit)(void*);
+  void (*xShutdown)(void*);
+  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+  int (*xPagecount)(sqlite3_pcache*);
+  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+  void (*xDestroy)(sqlite3_pcache*);
+};
+
+/*
+** CAPI3REF: Online Backup Object
+** EXPERIMENTAL
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation.  The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+** EXPERIMENTAL
+**
+** This API is used to overwrite the contents of one database with that
+** of another. It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files. 
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** Exclusive access is required to the destination database for the 
+** duration of the operation. However the source database is only
+** read-locked while it is actually being read, it is not locked
+** continuously for the entire operation. Thus, the backup may be
+** performed on a live database without preventing other users from
+** writing to the database for an extended period of time.
+** 
+** To perform a backup operation: 
+**   <ol>
+**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
+**         backup, 
+**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 
+**         the data between the two databases, and finally
+**     <li><b>sqlite3_backup_finish()</b> is called to release all resources 
+**         associated with the backup operation. 
+**   </ol>
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** <b>sqlite3_backup_init()</b>
+**
+** The first two arguments passed to [sqlite3_backup_init()] are the database
+** handle associated with the destination database and the database name 
+** used to attach the destination database to the handle. The database name
+** is "main" for the main database, "temp" for the temporary database, or
+** the name specified as part of the [ATTACH] statement if the destination is
+** an attached database. The third and fourth arguments passed to 
+** sqlite3_backup_init() identify the [database connection]
+** and database name used
+** to access the source database. The values passed for the source and 
+** destination [database connection] parameters must not be the same.
+**
+** If an error occurs within sqlite3_backup_init(), then NULL is returned
+** and an error code and error message written into the [database connection] 
+** passed as the first argument. They may be retrieved using the
+** [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()] functions.
+** Otherwise, if successful, a pointer to an [sqlite3_backup] object is
+** returned. This pointer may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup 
+** operation.
+**
+** <b>sqlite3_backup_step()</b>
+**
+** Function [sqlite3_backup_step()] is used to copy up to nPage pages between 
+** the source and destination databases, where nPage is the value of the 
+** second parameter passed to sqlite3_backup_step(). If nPage is a negative
+** value, all remaining source pages are copied. If the required pages are 
+** succesfully copied, but there are still more pages to copy before the 
+** backup is complete, it returns [SQLITE_OK]. If no error occured and there 
+** are no more pages to copy, then [SQLITE_DONE] is returned. If an error 
+** occurs, then an SQLite error code is returned. As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** As well as the case where the destination database file was opened for
+** read-only access, sqlite3_backup_step() may return [SQLITE_READONLY] if
+** the destination is an in-memory database with a different page size
+** from the source database.
+**
+** If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). If the 
+** busy-handler returns non-zero before the lock is available, then 
+** [SQLITE_BUSY] is returned to the caller. In this case the call to
+** sqlite3_backup_step() can be retried later. If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then 
+** there is no point in retrying the call to sqlite3_backup_step(). These 
+** errors are considered fatal. At this point the application must accept 
+** that the backup operation has failed and pass the backup operation handle 
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** Following the first call to sqlite3_backup_step(), an exclusive lock is
+** obtained on the destination file. It is not released until either 
+** sqlite3_backup_finish() is called or the backup operation is complete 
+** and sqlite3_backup_step() returns [SQLITE_DONE]. Additionally, each time 
+** a call to sqlite3_backup_step() is made a [shared lock] is obtained on
+** the source database file. This lock is released before the
+** sqlite3_backup_step() call returns. Because the source database is not
+** locked between calls to sqlite3_backup_step(), it may be modified mid-way
+** through the backup procedure. If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be transparently
+** restarted by the next call to sqlite3_backup_step(). If the source 
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is transparently 
+** updated at the same time.
+**
+** <b>sqlite3_backup_finish()</b>
+**
+** Once sqlite3_backup_step() has returned [SQLITE_DONE], or when the 
+** application wishes to abandon the backup operation, the [sqlite3_backup]
+** object should be passed to sqlite3_backup_finish(). This releases all
+** resources associated with the backup operation. If sqlite3_backup_step()
+** has not yet returned [SQLITE_DONE], then any active write-transaction on the
+** destination database is rolled back. The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** The value returned by sqlite3_backup_finish is [SQLITE_OK] if no error
+** occurred, regardless or whether or not sqlite3_backup_step() was called
+** a sufficient number of times to complete the backup operation. Or, if
+** an out-of-memory condition or IO error occured during a call to
+** sqlite3_backup_step() then [SQLITE_NOMEM] or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] error code
+** is returned. In this case the error code and an error message are
+** written to the destination [database connection].
+**
+** A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() is
+** not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
+**
+** Each call to sqlite3_backup_step() sets two values stored internally
+** by an [sqlite3_backup] object. The number of pages still to be backed
+** up, which may be queried by sqlite3_backup_remaining(), and the total
+** number of pages in the source database file, which may be queried by
+** sqlite3_backup_pagecount().
+**
+** The values returned by these functions are only updated by
+** sqlite3_backup_step(). If the source database is modified during a backup
+** operation, then the values are not updated to account for any extra
+** pages that need to be updated or the size of the source database file
+** changing.
+**
+** <b>Concurrent Usage of Database Handles</b>
+**
+** The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination database
+** connection handle is not passed to any other API (by any thread) after 
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish(). Unfortunately SQLite does not currently check
+** for this, if the application does use the destination [database connection]
+** for some other purpose during a backup operation, things may appear to
+** work correctly but in fact be subtly malfunctioning.  Use of the
+** destination database connection while a backup is in progress might
+** also cause a mutex deadlock.
+**
+** Furthermore, if running in [shared cache mode], the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the file-system file being 
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple 
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+  sqlite3 *pDest,                        /* Destination database handle */
+  const char *zDestName,                 /* Destination database name */
+  sqlite3 *pSource,                      /* Source database handle */
+  const char *zSourceName                /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+** EXPERIMENTAL
+**
+** When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 
+** This API may be used to register a callback that SQLite will invoke 
+** when the connection currently holding the required lock relinquishes it.
+** This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back. 
+**
+** When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. After an 
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as 
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().
+**
+** If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of 
+** the other connections to use as the blocking connection.
+**
+** There may be at most one unlock-notify callback registered by a 
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old. If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is cancelled. The blocked connections 
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** <b>Callback Invocation Details</b>
+**
+** When an unlock-notify callback is registered, the application provides a 
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions 
+** related to the set of unblocked database connections.
+**
+** <b>Deadlock Detection</b>
+**
+** Assuming that after registering for an unlock-notify callback a 
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. Any
+** number of levels of indirection are allowed.
+**
+** <b>The "DROP TABLE" Exception</b>
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just 
+** SQLITE_LOCKED.
+*/
+SQLITE_API int sqlite3_unlock_notify(
+  sqlite3 *pBlocked,                          /* Waiting connection */
+  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
+  void *pNotifyArg                            /* Argument to pass to xNotify */
+);
+
+
+/*
+** CAPI3REF: String Comparison
+** EXPERIMENTAL
+**
+** The [sqlite3_strnicmp()] API allows applications and extensions to
+** compare the contents of two buffers containing UTF-8 strings in a
+** case-indendent fashion, using the same definition of case independence 
+** that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
 
 /*
 ** Undo the hack that converts floating point types to integer for
@@ -5636,3 +5760,4 @@ int sqlite3_test_control(int op, ...);
 }  /* End of the 'extern "C"' block */
 #endif
 #endif
+
-- 
cgit v0.12


From c42bc88a9f366899747945a4478492cf765c7166 Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Wed, 21 Oct 2009 12:48:30 +1000
Subject: Trolltech modifications to SQLite.

* Include <qconfig.h> and rely on Qt's QT_NO_THREAD
  instdead of SQLite's THREADSAFE to toggle source code
  releated to threading in SQLite.

* compilation for Windows CE 6
  While for WinCE 5 localtime is declared but not defined
  in the libraries, for CE 6 they are not even declared.
  That usually makes sense but sqlite relies on it being
  present in time.h. As sqlite defines their own localtime
  for Windows CE, we "only" need to forward declare it
  earlier.

Conflicts:

	src/3rdparty/sqlite/sqlite3.c
---
 src/3rdparty/sqlite/sqlite3.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/3rdparty/sqlite/sqlite3.c b/src/3rdparty/sqlite/sqlite3.c
index 8ca6a82..e61cd38 100644
--- a/src/3rdparty/sqlite/sqlite3.c
+++ b/src/3rdparty/sqlite/sqlite3.c
@@ -11405,8 +11405,19 @@ static void clearYMD_HMS_TZ(DateTime *p){
 
 #ifndef SQLITE_OMIT_LOCALTIME
 /*
+** Windows CE does not declare the localtime
+** function as it is not defined anywhere.
+** Anyway we need the forward-declaration to be
+** able to define it later on.
+*/
+#if defined(_WIN32_WCE) && (_WIN32_WCE >= 0x600)
+struct tm *__cdecl localtime(const time_t *t);
+#endif
+
+/*
 ** Compute the difference (in milliseconds)
 ** between localtime and UTC (a.k.a. GMT)
+
 ** for the time value p where p is in UTC.
 */
 static sqlite3_int64 localtimeOffset(DateTime *p){
@@ -21387,6 +21398,8 @@ SQLITE_API int sqlite3_os_end(void){
 */
 #if SQLITE_OS_UNIX              /* This file is used on unix only */
 
+#include <qconfig.h>
+
 /*
 ** There are various methods for file locking used for concurrency
 ** control:
@@ -21476,7 +21489,7 @@ SQLITE_API int sqlite3_os_end(void){
 ** If we are to be thread-safe, include the pthreads header and define
 ** the SQLITE_UNIX_THREADS macro.
 */
-#if SQLITE_THREADSAFE
+#ifndef QT_NO_THREAD
 # define SQLITE_UNIX_THREADS 1
 #endif
 
@@ -26995,6 +27008,8 @@ SQLITE_API int sqlite3_os_end(void){
 ** desktops but not so well in embedded systems.
 */
 
+#include <qconfig.h>
+
 #include <winbase.h>
 
 #ifdef __CYGWIN__
@@ -27004,7 +27019,7 @@ SQLITE_API int sqlite3_os_end(void){
 /*
 ** Macros used to determine whether or not to use threads.
 */
-#if defined(THREADSAFE) && THREADSAFE
+#ifndef QT_NO_THREAD
 # define SQLITE_W32_THREADS 1
 #endif
 
-- 
cgit v0.12


From 0d61cf15358e1ff0b5125542ed4a9c4b7e96c141 Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Wed, 21 Oct 2009 12:51:12 +1000
Subject: Fixes: WebKit Windows CE build Details: Details: Make localtime a
 static function. This is needed for linking sqlite3.lib into webkit and it
 generally makes sense for our build of sqlite using the amalgamated build.

(cherry picked from commit 5e326c74239eecbd3e64df90ebbafaf51530d43d)
---
 src/3rdparty/sqlite/sqlite3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/3rdparty/sqlite/sqlite3.c b/src/3rdparty/sqlite/sqlite3.c
index e61cd38..90a64ba 100644
--- a/src/3rdparty/sqlite/sqlite3.c
+++ b/src/3rdparty/sqlite/sqlite3.c
@@ -27489,7 +27489,7 @@ static char *utf8ToMbcs(const char *zFilename){
 ** WindowsCE does not have a localtime() function.  So create a
 ** substitute.
 */
-struct tm *__cdecl localtime(const time_t *t)
+static struct tm *__cdecl localtime(const time_t *t)
 {
   static struct tm y;
   FILETIME uTm, lTm;
-- 
cgit v0.12


From 84cf05349fa3e106a498dc479f44bbd0cc402f2a Mon Sep 17 00:00:00 2001
From: Bill King <bill.king@nokia.com>
Date: Wed, 21 Oct 2009 14:14:18 +1000
Subject: VXWorks changes.

Forward port the vxworks changes from d7b688870aead912690188b324d370b920a7a600
---
 src/3rdparty/sqlite/sqlite3.c | 29 ++++++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/3rdparty/sqlite/sqlite3.c b/src/3rdparty/sqlite/sqlite3.c
index 90a64ba..46d3dfc 100644
--- a/src/3rdparty/sqlite/sqlite3.c
+++ b/src/3rdparty/sqlite/sqlite3.c
@@ -420,7 +420,7 @@
 **
 ** See also ticket #2741.
 */
-#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
+#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE && !defined(VXWORKS)
 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
 #endif
 
@@ -564,6 +564,13 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
+
+#ifdef VXWORKS
+# define SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+# define NO_GETTOD
+# include <ioLib.h>
+#endif
+
 #include <stdarg.h>     /* Needed for the definition of va_list */
 
 /*
@@ -21470,7 +21477,11 @@ SQLITE_API int sqlite3_os_end(void){
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
-#include <sys/time.h>
+#ifdef VXWORKS
+# include <sys/times.h>
+#else
+# include <sys/time.h>
+#endif
 #include <errno.h>
 
 #if SQLITE_ENABLE_LOCKING_STYLE
@@ -24411,7 +24422,11 @@ static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
     }
     return -1;
   }
-  got = write(id->h, pBuf, cnt);
+# ifndef VXWORKS
+   got = write(id->h, pBuf, cnt);
+# else
+  got = write(id->h, (char *)pBuf, cnt);
+# endif
 #endif
   TIMER_END;
   if( got<0 ){
@@ -25808,12 +25823,16 @@ static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
 #if !defined(SQLITE_TEST)
   {
     int pid, fd;
-    fd = open("/dev/urandom", O_RDONLY);
+    fd = open("/dev/urandom", O_RDONLY, 0);
     if( fd<0 ){
       time_t t;
       time(&t);
       memcpy(zBuf, &t, sizeof(t));
-      pid = getpid();
+#ifndef VXWORKS
+       pid = getpid();
+#else
+      pid = (int)taskIdCurrent();
+#endif
       memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid));
       assert( sizeof(t)+sizeof(pid)<=(size_t)nBuf );
       nBuf = sizeof(t) + sizeof(pid);
-- 
cgit v0.12


From efd2bbd159bb4810ed828c842f459e6fcb8eb783 Mon Sep 17 00:00:00 2001
From: Peter Yard <peter.yard@nokia.com>
Date: Wed, 21 Oct 2009 16:07:42 +1000
Subject: Included table for definition of plural forms for different
 languages.

---
 doc/src/internationalization/linguist-manual.qdoc | 337 +++++++++++++++++++++-
 1 file changed, 334 insertions(+), 3 deletions(-)

diff --git a/doc/src/internationalization/linguist-manual.qdoc b/doc/src/internationalization/linguist-manual.qdoc
index 065fb6b..5d388f1 100644
--- a/doc/src/internationalization/linguist-manual.qdoc
+++ b/doc/src/internationalization/linguist-manual.qdoc
@@ -327,7 +327,7 @@
     area}. The \l{Context Window} {context list} is normally shown
     on the left, and the \l{Sources and Forms Window} {source code},
     \l{Strings Window} {string list}, and either the \l{Phrases and 
-    Guesses Window} {prhrases and guesses}, or the \l{Warnings Window} 
+    Guesses Window} {phrases and guesses}, or the \l{Warnings Window}
     {warnings} are shown above and below the \l{The Translation Area}
     {translations area}.
 
@@ -355,7 +355,7 @@
     translation "guesses" have been read from phrase books
     (\menu{Phrases|Open Phrase Book...}).  The current string's
     current translation is also shown here. To select a guess, double
-    click it in the prases and guesses window or use the keyboard
+    click it in the phrases and guesses window or use the keyboard
     shortcut shown to the right of the guess.
 
     \QL can automatically check whether your translation strings pass
@@ -764,7 +764,7 @@
     and \e{N}.
 
     Each Ctrl key accelerator is shown in the \l{Strings Window}
-    {string list} as a separte string, e.g. \key{Ctrl+Enter}. Since
+    {string list} as a separate string, e.g. \key{Ctrl+Enter}. Since
     the string doesn't have a context to give it meaning, e.g. like
     the context of the phrase in which an Alt key accelerator appears,
     the translator must rely on the UI developer to include a
@@ -808,6 +808,337 @@
     of where argument \e{i} appears in the argument sequence in the
     source string.
 
+    \section2 Plurals
+
+    The problem of plurals in output is resolved by using an overload of
+    the \c tr() function with the signature
+    \code
+    QString  tr(const char *text, const char *comment, int n);
+    \endcode
+    Using built in comparisons for the value of \c n the tr() function will
+    translate the phrase to the plural form for the target language.
+
+    Different languages have various forms for plurals beyond simply
+    \e singular and \e plural. The rules for determining which form of the
+    plural to use are encoded as conditional tests. Below is a table
+    representing the numbers associated with the forms rather than the
+    conditional tests themselves.
+
+
+
+    \table 90%
+        \header
+            \o Language
+            \o Form 1
+            \o Form 2
+            \o Form 3
+            \o Form 4
+        \row
+            \o Arabic
+            \o 0, 1, 11-102, 111-202...
+            \o 2
+            \o 3-10, 103-110, 203-210...
+            \o
+        \row
+            \o Basque
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Bulgarian
+            \o 1
+            \o 0, 2-100, 101-
+            \o
+            \o 
+        \row
+            \o Catalan
+            \o 1
+            \o 11, 11 000-11 999, 11 000 000-11 999 999...
+            \o 0, 2-10, 12-10 999, 12-10 999 999...
+            \o 
+        \row
+            \o Chinese-CN
+            \o 0-
+            \o
+            \o
+            \o 
+        \row
+            \o Chinese-HK
+            \o 0-
+            \o
+            \o
+            \o 
+        \row
+            \o Chinese-TW
+            \o 0-
+            \o
+            \o
+            \o 
+        \row
+            \o Croation
+            \o 1, 21, 31, 41, 51, 61, 71, 81, 91, 101...
+            \o 2-4, 22-24, 32-34, 42-44...
+            \o 0, 5-20, 25-30, 35-40...
+            \o 
+        \row
+            \o Czech
+            \o 1
+            \o 2-4
+            \o 0, 5-
+            \o 
+        \row
+            \o Danish
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Dutch
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o English
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o English-US
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Estonian
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Finnish
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o French-CA
+            \o 0, 1
+            \o 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o French-FR
+            \o 0, 1
+            \o 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Galician
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o German
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Greek
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Hebrew
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o 
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Hungarian
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Icelandic
+            \o 1, 21, 31, 41, 51....101, 121, 131...
+            \o 0, 2-20, 22-30, 32-40...102-120...
+            \o 
+            \o 
+        \row
+            \o Indonesian
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Italian
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Japanese
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Korean
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Latvian
+            \o 0
+            \o 1, 21, 31, 41, 51, 61, 71, 81, 91, 101, 131, 141...
+            \o 2-20, 22-30, 32-40, 42-50...202-220, 222-230...
+            \o 
+        \row
+            \o Lithuanian
+            \o 1, 21, 31, 41, 51...101, 121, 131...
+            \o 2-9, 22-29, 32-39...102-109, 122-129, 132-139...
+            \o 0, 10-20, 30, 40, 50...110-120, 130, 140...
+            \o 
+        \row
+            \o Malay
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Norwegian
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Persian
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Polish
+            \o 1
+            \o 2-4, 22-24, 32-34...
+            \o 5-21, 25-31, 35-41...
+            \o 
+        \row
+            \o Portugese-BR
+            \o 0, 1
+            \o 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Portugese-PT
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Romanian
+            \o 1
+            \o 0, 2-19, 101-119, 201-219...
+            \o 20-100, 120-200, 220-300...
+            \o 
+        \row
+            \o Russian
+            \o 1, 21, 31, 41, 51, 61, 71, 81, 91, 101...
+            \o 2-4, 22-24, 32-34...
+            \o 0, 5-20, 25-30, 35-40...
+            \o 
+        \row
+            \o Serbian
+            \o 1, 21, 31, 41, 51, 61, 71, 81, 91, 101...
+            \o 2-4, 22-24, 32-34...
+            \o 0, 5-20, 25-30, 35-40...
+            \o 
+        \row
+            \o Slovak
+            \o 1
+            \o 2-4
+            \o 0, 5-20, 25-30, 35-40...
+            \o 
+        \row
+            \o Slovene
+            \o 1, 101, 201, 301...
+            \o 2, 102, 202, 302...
+            \o 3, 4, 103, 104, 203, 204, 303, 304...
+            \o 0, 5-100, 105-200, 205-300...
+        \row
+            \o Spanish-US
+            \o 1
+            \o 0, 2-
+            \o 
+            \o 
+        \row
+            \o Spanish-ES
+            \o 1
+            \o 0, 2-
+            \o 
+            \o 
+        \row
+            \o Swedish
+            \o 1
+            \o 0, 2-100, 101-
+            \o 
+            \o 
+        \row
+            \o Tagalog
+            \o 0, 1
+            \o 2, 3, 5, 7-8, 10-13, 15, 17-18, 20-23...101...1001
+            \o 4, 6, 9, 14, 16, 19, 24, 26, 29...104, 106, 109...
+            \o 
+        \row
+            \o Thai
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Turkish
+            \o 0-
+            \o 
+            \o 
+            \o 
+        \row
+            \o Ukrainian
+            \o 1, 21, 31, 41, 51, 61, 71, 81, 91, 101...
+            \o 2-4, 22-24, 32-34...
+            \o 0, 5-20, 25-30, 35-40...
+            \o 
+        \row
+            \o Urdu
+            \o 1
+            \o 0, 2-100, 101-
+            \o
+            \o 
+        \row
+            \o Vietnamese
+            \o 0-
+            \o 
+            \o 
+            \o 
+    \endtable
+
+    These rules are embedded within the Qt libraries, there is no need for
+    the developer to know them. Merely to use the correct \c tr() call.
+
+
     \section2 Reusing Translations
 
     If the translated text is similar to the source text, choose the
-- 
cgit v0.12


From a6af1538ea53408399fb29870a4ef16a92c7893a Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Mon, 19 Oct 2009 16:51:33 +0200
Subject: Switch from *-armv5 to *-armv6.

Change from armv5 to armv6 by default. This updates documentation, the
convenience scripts, and the Raptor/abld qmake generator to use armv6 instead.

Task-number: QTBUG-4891
Reviewed-by: Jason Barron
---
 README.s60                                         |   8 ++++----
 bin/createpackage.pl                               |   4 ++--
 bin/patch_capabilities.pl                          |   2 +-
 configure.exe                                      | Bin 2170880 -> 1169408 bytes
 .../snippets/code/doc_src_s60-introduction.qdoc    |   6 +++---
 qmake/generators/symbian/symmake_abld.cpp          |   6 +++---
 qmake/generators/symbian/symmake_sbsv2.cpp         |   6 +++---
 tools/configure/configureapp.cpp                   |   2 +-
 8 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/README.s60 b/README.s60
index 2137135..87259c1 100644
--- a/README.s60
+++ b/README.s60
@@ -148,7 +148,7 @@ many example programs in Qt's examples directory.
 
     To build Qt for the device, type:
 
-        make release-armv5
+        make release-armv6
  
     Congratulations, Qt is now ready to use.
 
@@ -159,7 +159,7 @@ many example programs in Qt's examples directory.
     a real device, you first have to install the Qt libraries on the device:
 
         cd src\s60installs
-        createpackage -i Qt_for_S60_template.pkg release-armv5 <certificate file> <certificate key file>
+        createpackage -i Qt_for_S60_template.pkg release-armv6 <certificate file> <certificate key file>
 
     Note: You will need to supply certificate that allows installation of 
           binaries with "All -Tcb" capability to your device.
@@ -167,9 +167,9 @@ many example programs in Qt's examples directory.
     Similarly, install fluidlauncher to the device:
 
         cd embedded\fluidlauncher
-        createpackage -i fluidlauncher_template.pkg release-armv5
+        createpackage -i fluidlauncher_template.pkg release-armv6
 
-    This will create a self-signed fluidlauncher_release-armv5.sis and install it to your device.
+    This will create a self-signed fluidlauncher_release-armv6.sis and install it to your device.
 
     To run the demos on the emulator simply navigate to the directory of the demo and run:
 
diff --git a/bin/createpackage.pl b/bin/createpackage.pl
index 7e87758..fe141d7 100755
--- a/bin/createpackage.pl
+++ b/bin/createpackage.pl
@@ -85,10 +85,10 @@ Where parameters are as follows:
      passphrase              = The certificate's private key file's passphrase
 
 Example:
-     createpackage.pl fluidlauncher_template.pkg release-armv5
+     createpackage.pl fluidlauncher_template.pkg release-armv6
      
 Example with certfile:
-     createpackage.pl -c=mycerts.txt fluidlauncher_template.pkg release-armv5
+     createpackage.pl -c=mycerts.txt fluidlauncher_template.pkg release-armv6
      
      Content of 'mycerts.txt' must be something like this:
         # This is comment line, also the empty lines are ignored
diff --git a/bin/patch_capabilities.pl b/bin/patch_capabilities.pl
index bfd34f0..e570632 100755
--- a/bin/patch_capabilities.pl
+++ b/bin/patch_capabilities.pl
@@ -53,7 +53,7 @@ sub Usage() {
     print("capabilities supported by self-signed certificates.\n");
     print("\n *** NOTE: If *_template.pkg file is given, 'target-platform' is REQUIRED. ***\n");
     print("\nUsage: patch_capabilities.pl pkg_filename <target-platform> [capability list]\n");
-    print("\nE.g. patch_capabilities.pl myapp_template.pkg release-armv5 \"All -TCB\"\n");
+    print("\nE.g. patch_capabilities.pl myapp_template.pkg release-armv6 \"All -TCB\"\n");
     exit();
 }
 
diff --git a/configure.exe b/configure.exe
index dabf10c..fc95f90 100755
Binary files a/configure.exe and b/configure.exe differ
diff --git a/doc/src/snippets/code/doc_src_s60-introduction.qdoc b/doc/src/snippets/code/doc_src_s60-introduction.qdoc
index 8949df6..c9c6fd9 100644
--- a/doc/src/snippets/code/doc_src_s60-introduction.qdoc
+++ b/doc/src/snippets/code/doc_src_s60-introduction.qdoc
@@ -50,16 +50,16 @@
 
 //! [2]
     qmake
-    make debug-winscw release-armv5
+    make debug-winscw release-armv6
     make sis
 //! [2]
 
 //! [3]
-   make sis QT_SIS_TARGET=debug-armv5
+   make sis QT_SIS_TARGET=debug-armv6
 //! [3]
 
 //! [4]
-   set QT_SIS_TARGET=debug-armv5
+   set QT_SIS_TARGET=debug-armv6
    make sis
 //! [4]
 
diff --git a/qmake/generators/symbian/symmake_abld.cpp b/qmake/generators/symbian/symmake_abld.cpp
index 4d1673b..692ead7 100644
--- a/qmake/generators/symbian/symmake_abld.cpp
+++ b/qmake/generators/symbian/symmake_abld.cpp
@@ -224,8 +224,8 @@ void SymbianAbldMakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, bool
     t << "first: default" << endl;
     if (debugPlatforms.contains("winscw"))
         t << "default: debug-winscw";
-    else if (debugPlatforms.contains("armv5"))
-        t << "default: debug-armv5";
+    else if (debugPlatforms.contains("armv6"))
+        t << "default: debug-armv6";
     else if (debugPlatforms.size())
         t << "default: debug-" << debugPlatforms.first();
     else
@@ -259,7 +259,7 @@ void SymbianAbldMakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, bool
         }
         t << endl;
 
-        // For more specific builds, targets are in this form: build-platform, e.g. release-armv5
+        // For more specific builds, targets are in this form: build-platform, e.g. release-armv6
         foreach(QString item, debugPlatforms) {
             t << "debug-" << item << ": $(ABLD)" << endl;
             t << "\t$(ABLD)" << testClause << " build " << item << " udeb" << endl;
diff --git a/qmake/generators/symbian/symmake_sbsv2.cpp b/qmake/generators/symbian/symmake_sbsv2.cpp
index cad2736..bcb93af 100644
--- a/qmake/generators/symbian/symmake_sbsv2.cpp
+++ b/qmake/generators/symbian/symmake_sbsv2.cpp
@@ -150,8 +150,8 @@ void SymbianSbsv2MakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, boo
     t << "first: default" << endl;
     if (debugPlatforms.contains("winscw"))
         t << "default: debug-winscw";
-    else if (debugPlatforms.contains("armv5"))
-        t << "default: debug-armv5";
+    else if (debugPlatforms.contains("armv6"))
+        t << "default: debug-armv6";
     else if (debugPlatforms.size())
         t << "default: debug-" << debugPlatforms.first();
     else
@@ -182,7 +182,7 @@ void SymbianSbsv2MakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, boo
         }
         t << endl;
 
-        // For more specific builds, targets are in this form: build-platform, e.g. release-armv5
+        // For more specific builds, targets are in this form: build-platform, e.g. release-armv6
         foreach(QString item, debugPlatforms) {
             t << "debug-" << item << ": " << BLD_INF_FILENAME << endl;
             t << "\t$(SBS) -c " << item << "_udeb" << testClause << endl;
diff --git a/tools/configure/configureapp.cpp b/tools/configure/configureapp.cpp
index f57f3a8..02375b3 100644
--- a/tools/configure/configureapp.cpp
+++ b/tools/configure/configureapp.cpp
@@ -1164,7 +1164,7 @@ void Configure::parseCmdLine()
     dictionary["QTBUILDINSTRUCTION"] = dictionary["MAKE"];
     if (dictionary.contains("XQMAKESPEC")) {
         if (dictionary["XQMAKESPEC"].startsWith("symbian")) {
-            dictionary["QTBUILDINSTRUCTION"] = QString("make debug-winscw|debug-armv5|release-armv5");
+            dictionary["QTBUILDINSTRUCTION"] = QString("make debug-winscw|debug-armv6|release-armv6");
         } else if (dictionary["XQMAKESPEC"].startsWith("wince")) {
             dictionary["QTBUILDINSTRUCTION"] =
                 QString("setcepaths.bat ") + dictionary["XQMAKESPEC"] + QString(" && ") + dictionary["MAKE"];
-- 
cgit v0.12


From 4b678fe08ec8de5a34d8b2ec2d9ec44276424636 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sami=20Meril=C3=A4?= <sami.merila@nokia.com>
Date: Wed, 21 Oct 2009 12:09:39 +0300
Subject: S60Style's tab widget is too small for touch use

TabWidget for S60Style is too small for touch use, it is rather hard to
accurately touch the tabpane to switch the active tab.
To fix this, we ask the native tabpane height from AVKON and set the
QTabWiget's pane height to native height (or bigger).

Task-number: QTBUG-4243
Reviewed-by: Alessandro Portale
---
 src/gui/styles/qs60style.cpp           | 14 ++++++++++----
 src/gui/styles/qs60style_p.h           |  2 ++
 src/gui/styles/qs60style_s60.cpp       | 20 ++++++++++++++++++++
 src/gui/styles/qs60style_simulated.cpp |  4 ++++
 4 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/src/gui/styles/qs60style.cpp b/src/gui/styles/qs60style.cpp
index 6d95336..4c6bc46 100644
--- a/src/gui/styles/qs60style.cpp
+++ b/src/gui/styles/qs60style.cpp
@@ -1844,8 +1844,8 @@ void QS60Style::drawControl(ControlElement element, const QStyleOption *option,
                 //todo: update to horizontal table graphic
                 QS60StylePrivate::drawSkinElement(QS60StylePrivate::SE_TableHeaderItem, painter, option->rect, flags | QS60StylePrivate::SF_PointWest);
             }
-        } else if (qobject_cast<const QFrame *>(widget)) { 
-            QCommonStyle::drawControl(element, option, painter, widget); 
+        } else if (qobject_cast<const QFrame *>(widget)) {
+            QCommonStyle::drawControl(element, option, painter, widget);
         }
         break;
     case CE_MenuScroller:
@@ -2216,6 +2216,12 @@ QSize QS60Style::sizeFromContents(ContentsType ct, const QStyleOption *opt,
             if (const QStyleOptionFrame *f = qstyleoption_cast<const QStyleOptionFrame *>(opt))
                 sz += QSize(2*f->lineWidth, 4*f->lineWidth);
             break;
+        case CT_TabBarTab:
+            QSize naviPaneSize = QS60StylePrivate::naviPaneSize();
+            sz = QCommonStyle::sizeFromContents( ct, opt, csz, widget);
+            if (naviPaneSize.height() > sz.height())
+                sz.setHeight(naviPaneSize.height());
+            break;
         default:
             sz = QCommonStyle::sizeFromContents( ct, opt, csz, widget);
             break;
@@ -2425,8 +2431,8 @@ QRect QS60Style::subControlRect(ComplexControl control, const QStyleOptionComple
                 case SC_ComboBoxArrow:
                     ret.setRect(
                         ret.x() + ret.width() - buttonMargin - buttonWidth,
-                        ret.y() + buttonMargin, 
-                        buttonWidth, 
+                        ret.y() + buttonMargin,
+                        buttonWidth,
                         height - 2*buttonMargin);
                     break;
                 case SC_ComboBoxEditField: {
diff --git a/src/gui/styles/qs60style_p.h b/src/gui/styles/qs60style_p.h
index 5422ff6..8e53eee 100644
--- a/src/gui/styles/qs60style_p.h
+++ b/src/gui/styles/qs60style_p.h
@@ -460,6 +460,8 @@ public:
     void handleSkinChange();
 #endif // Q_WS_S60
 
+    static QSize naviPaneSize();
+
 private:
     static void drawPart(QS60StyleEnums::SkinParts part, QPainter *painter,
         const QRect &rect, SkinElementFlags flags = KDefaultSkinElementFlags);
diff --git a/src/gui/styles/qs60style_s60.cpp b/src/gui/styles/qs60style_s60.cpp
index d760016..9765066 100644
--- a/src/gui/styles/qs60style_s60.cpp
+++ b/src/gui/styles/qs60style_s60.cpp
@@ -61,6 +61,7 @@
 #include <AknFontAccess.h>
 #include <AknLayoutFont.h>
 #include <aknutils.h>
+#include <aknnavi.h>
 
 #if !defined(QT_NO_STYLE_S60) || defined(QT_PLUGIN)
 
@@ -104,6 +105,7 @@ public:
     static bool disabledPartGraphic(QS60StyleEnums::SkinParts &part);
     static bool disabledFrameGraphic(QS60StylePrivate::SkinFrameElements &frame);
     static QPixmap generateMissingThemeGraphic(QS60StyleEnums::SkinParts &part, const QSize &size, QS60StylePrivate::SkinElementFlags flags);
+    static QSize naviPaneSize();
 
 private:
     static QPixmap createSkinnedGraphicsLX(QS60StyleEnums::SkinParts part,
@@ -1388,6 +1390,24 @@ void QS60StylePrivate::handleSkinChange()
         topLevelWidget->ensurePolished();
     }
 }
+
+QSize QS60StylePrivate::naviPaneSize()
+{
+    return QS60StyleModeSpecifics::naviPaneSize();
+}
+
+QSize QS60StyleModeSpecifics::naviPaneSize()
+{
+    CAknNavigationControlContainer* naviContainer;
+    if (S60->statusPane())
+        naviContainer = static_cast<CAknNavigationControlContainer*>
+            (S60->statusPane()->ControlL(TUid::Uid(EEikStatusPaneUidNavi)));
+    if (naviContainer)
+        return QSize(naviContainer->Size().iWidth, naviContainer->Size().iHeight);
+    else
+        return QSize(0,0);
+}
+
 #endif // Q_WS_S60
 
 QT_END_NAMESPACE
diff --git a/src/gui/styles/qs60style_simulated.cpp b/src/gui/styles/qs60style_simulated.cpp
index 89a9158..8a2616d 100644
--- a/src/gui/styles/qs60style_simulated.cpp
+++ b/src/gui/styles/qs60style_simulated.cpp
@@ -326,6 +326,10 @@ QPixmap QS60StylePrivate::backgroundTexture()
     return *m_background;
 }
 
+QSize QS60StylePrivate::naviPaneSize()
+{
+    return QSize(0, 0);
+}
 
 bool QS60StylePrivate::isTouchSupported()
 {
-- 
cgit v0.12


From ee8769ddaff1b69bfd1a959c3c58a96416736890 Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Wed, 21 Oct 2009 12:28:00 +0300
Subject: Fixed .make.cache write collision on symbian-sbsv2 builds

If a project was built for more than one target with single sbs
command, .make.cache generation could sometime fail because multiple
jobs attempted to write into it simultaneously. Now only one of the
specified targets will be used to generate .make.cache, making
collisions impossible.

Reviewed-by: Janne Anttila
---
 mkspecs/symbian-sbsv2/flm/qt/qmake_store_build.flm | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/mkspecs/symbian-sbsv2/flm/qt/qmake_store_build.flm b/mkspecs/symbian-sbsv2/flm/qt/qmake_store_build.flm
index 7fada1e..634fafa 100644
--- a/mkspecs/symbian-sbsv2/flm/qt/qmake_store_build.flm
+++ b/mkspecs/symbian-sbsv2/flm/qt/qmake_store_build.flm
@@ -9,6 +9,14 @@
 
 include $(FLMHOME)/metaflm.mk
 
+SINGLETON:=$(call sanitise,TSTORE_SINGLETON_$(EXTENSION_ROOT))
+
+ifeq ($($(SINGLETON)),)
+# Prevent duplicate targets from being created, as that can lead to build breaks
+# in multiprocessor systems if two or more targets try to write to .make.cache at
+# the same time.
+$(SINGLETON):=1
+
 STORE_BUILD_TARGET:=$(call sanitise,TSTORE_BUILD_$(PLATFORM_PATH)_$(CFG_PATH)_$(EXTENSION_ROOT))
 CACHE_FILENAME:=$(EXTENSION_ROOT)/.make.cache
 
@@ -37,4 +45,5 @@ endef
 
 $(eval $(qmake_store_build))
 $(eval $(call GenerateStandardCleanTarget,$(CACHE_FILENAME),''))
+endif
 
-- 
cgit v0.12


From f4a10959e579f6c8d77defa24107a5f6a02749b9 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Tue, 20 Oct 2009 15:19:37 +0200
Subject: don't remap VK_RETURN on Windows mobile if not in keypad navigation
 mode

Reviewed-by: TrustMe
---
 src/gui/kernel/qkeymapper_win.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/kernel/qkeymapper_win.cpp b/src/gui/kernel/qkeymapper_win.cpp
index be207df..f95efa2 100644
--- a/src/gui/kernel/qkeymapper_win.cpp
+++ b/src/gui/kernel/qkeymapper_win.cpp
@@ -438,10 +438,10 @@ static const Qt::KeyboardModifiers ModsTbl[] = {
 */
 inline int winceKeyBend(int keyCode)
 {
-#ifdef Q_OS_WINCE_WM
+#if defined(Q_OS_WINCE_WM) && defined(QT_KEYPAD_NAVIGATION)
     // remap return or action key to select key for windows mobile.
     // will be changed to a table remapping function in the next version (4.6/7).
-    if (keyCode == 13)
+    if (keyCode == VK_RETURN && QApplication::keypadNavigationEnabled())
         return Qt::Key_Select;
     else
         return KeyTbl[keyCode];
-- 
cgit v0.12


From 895046d54eee97d838dea1fdcb34a7dff3d91f98 Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Wed, 21 Oct 2009 12:07:46 +0200
Subject: Revert "Switch from *-armv5 to *-armv6."

This reverts commit a6af1538ea53408399fb29870a4ef16a92c7893a.

armv6 is not supported by public SDKs, due to armv6/urel not existing.
Such SDKs needs to be fixed by copying the armv5 files. Hence we revert,
and postpone until we have SDKs which actually support armv6, and until
we have a stronger insight into what advantages armv6 brings.
---
 README.s60                                         |   8 ++++----
 bin/createpackage.pl                               |   4 ++--
 bin/patch_capabilities.pl                          |   2 +-
 configure.exe                                      | Bin 1169408 -> 2170880 bytes
 .../snippets/code/doc_src_s60-introduction.qdoc    |   6 +++---
 qmake/generators/symbian/symmake_abld.cpp          |   6 +++---
 qmake/generators/symbian/symmake_sbsv2.cpp         |   6 +++---
 tools/configure/configureapp.cpp                   |   2 +-
 8 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/README.s60 b/README.s60
index 87259c1..2137135 100644
--- a/README.s60
+++ b/README.s60
@@ -148,7 +148,7 @@ many example programs in Qt's examples directory.
 
     To build Qt for the device, type:
 
-        make release-armv6
+        make release-armv5
  
     Congratulations, Qt is now ready to use.
 
@@ -159,7 +159,7 @@ many example programs in Qt's examples directory.
     a real device, you first have to install the Qt libraries on the device:
 
         cd src\s60installs
-        createpackage -i Qt_for_S60_template.pkg release-armv6 <certificate file> <certificate key file>
+        createpackage -i Qt_for_S60_template.pkg release-armv5 <certificate file> <certificate key file>
 
     Note: You will need to supply certificate that allows installation of 
           binaries with "All -Tcb" capability to your device.
@@ -167,9 +167,9 @@ many example programs in Qt's examples directory.
     Similarly, install fluidlauncher to the device:
 
         cd embedded\fluidlauncher
-        createpackage -i fluidlauncher_template.pkg release-armv6
+        createpackage -i fluidlauncher_template.pkg release-armv5
 
-    This will create a self-signed fluidlauncher_release-armv6.sis and install it to your device.
+    This will create a self-signed fluidlauncher_release-armv5.sis and install it to your device.
 
     To run the demos on the emulator simply navigate to the directory of the demo and run:
 
diff --git a/bin/createpackage.pl b/bin/createpackage.pl
index fe141d7..7e87758 100755
--- a/bin/createpackage.pl
+++ b/bin/createpackage.pl
@@ -85,10 +85,10 @@ Where parameters are as follows:
      passphrase              = The certificate's private key file's passphrase
 
 Example:
-     createpackage.pl fluidlauncher_template.pkg release-armv6
+     createpackage.pl fluidlauncher_template.pkg release-armv5
      
 Example with certfile:
-     createpackage.pl -c=mycerts.txt fluidlauncher_template.pkg release-armv6
+     createpackage.pl -c=mycerts.txt fluidlauncher_template.pkg release-armv5
      
      Content of 'mycerts.txt' must be something like this:
         # This is comment line, also the empty lines are ignored
diff --git a/bin/patch_capabilities.pl b/bin/patch_capabilities.pl
index e570632..bfd34f0 100755
--- a/bin/patch_capabilities.pl
+++ b/bin/patch_capabilities.pl
@@ -53,7 +53,7 @@ sub Usage() {
     print("capabilities supported by self-signed certificates.\n");
     print("\n *** NOTE: If *_template.pkg file is given, 'target-platform' is REQUIRED. ***\n");
     print("\nUsage: patch_capabilities.pl pkg_filename <target-platform> [capability list]\n");
-    print("\nE.g. patch_capabilities.pl myapp_template.pkg release-armv6 \"All -TCB\"\n");
+    print("\nE.g. patch_capabilities.pl myapp_template.pkg release-armv5 \"All -TCB\"\n");
     exit();
 }
 
diff --git a/configure.exe b/configure.exe
index fc95f90..dabf10c 100755
Binary files a/configure.exe and b/configure.exe differ
diff --git a/doc/src/snippets/code/doc_src_s60-introduction.qdoc b/doc/src/snippets/code/doc_src_s60-introduction.qdoc
index c9c6fd9..8949df6 100644
--- a/doc/src/snippets/code/doc_src_s60-introduction.qdoc
+++ b/doc/src/snippets/code/doc_src_s60-introduction.qdoc
@@ -50,16 +50,16 @@
 
 //! [2]
     qmake
-    make debug-winscw release-armv6
+    make debug-winscw release-armv5
     make sis
 //! [2]
 
 //! [3]
-   make sis QT_SIS_TARGET=debug-armv6
+   make sis QT_SIS_TARGET=debug-armv5
 //! [3]
 
 //! [4]
-   set QT_SIS_TARGET=debug-armv6
+   set QT_SIS_TARGET=debug-armv5
    make sis
 //! [4]
 
diff --git a/qmake/generators/symbian/symmake_abld.cpp b/qmake/generators/symbian/symmake_abld.cpp
index 692ead7..4d1673b 100644
--- a/qmake/generators/symbian/symmake_abld.cpp
+++ b/qmake/generators/symbian/symmake_abld.cpp
@@ -224,8 +224,8 @@ void SymbianAbldMakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, bool
     t << "first: default" << endl;
     if (debugPlatforms.contains("winscw"))
         t << "default: debug-winscw";
-    else if (debugPlatforms.contains("armv6"))
-        t << "default: debug-armv6";
+    else if (debugPlatforms.contains("armv5"))
+        t << "default: debug-armv5";
     else if (debugPlatforms.size())
         t << "default: debug-" << debugPlatforms.first();
     else
@@ -259,7 +259,7 @@ void SymbianAbldMakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, bool
         }
         t << endl;
 
-        // For more specific builds, targets are in this form: build-platform, e.g. release-armv6
+        // For more specific builds, targets are in this form: build-platform, e.g. release-armv5
         foreach(QString item, debugPlatforms) {
             t << "debug-" << item << ": $(ABLD)" << endl;
             t << "\t$(ABLD)" << testClause << " build " << item << " udeb" << endl;
diff --git a/qmake/generators/symbian/symmake_sbsv2.cpp b/qmake/generators/symbian/symmake_sbsv2.cpp
index bcb93af..cad2736 100644
--- a/qmake/generators/symbian/symmake_sbsv2.cpp
+++ b/qmake/generators/symbian/symmake_sbsv2.cpp
@@ -150,8 +150,8 @@ void SymbianSbsv2MakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, boo
     t << "first: default" << endl;
     if (debugPlatforms.contains("winscw"))
         t << "default: debug-winscw";
-    else if (debugPlatforms.contains("armv6"))
-        t << "default: debug-armv6";
+    else if (debugPlatforms.contains("armv5"))
+        t << "default: debug-armv5";
     else if (debugPlatforms.size())
         t << "default: debug-" << debugPlatforms.first();
     else
@@ -182,7 +182,7 @@ void SymbianSbsv2MakefileGenerator::writeWrapperMakefile(QFile& wrapperFile, boo
         }
         t << endl;
 
-        // For more specific builds, targets are in this form: build-platform, e.g. release-armv6
+        // For more specific builds, targets are in this form: build-platform, e.g. release-armv5
         foreach(QString item, debugPlatforms) {
             t << "debug-" << item << ": " << BLD_INF_FILENAME << endl;
             t << "\t$(SBS) -c " << item << "_udeb" << testClause << endl;
diff --git a/tools/configure/configureapp.cpp b/tools/configure/configureapp.cpp
index 02375b3..f57f3a8 100644
--- a/tools/configure/configureapp.cpp
+++ b/tools/configure/configureapp.cpp
@@ -1164,7 +1164,7 @@ void Configure::parseCmdLine()
     dictionary["QTBUILDINSTRUCTION"] = dictionary["MAKE"];
     if (dictionary.contains("XQMAKESPEC")) {
         if (dictionary["XQMAKESPEC"].startsWith("symbian")) {
-            dictionary["QTBUILDINSTRUCTION"] = QString("make debug-winscw|debug-armv6|release-armv6");
+            dictionary["QTBUILDINSTRUCTION"] = QString("make debug-winscw|debug-armv5|release-armv5");
         } else if (dictionary["XQMAKESPEC"].startsWith("wince")) {
             dictionary["QTBUILDINSTRUCTION"] =
                 QString("setcepaths.bat ") + dictionary["XQMAKESPEC"] + QString(" && ") + dictionary["MAKE"];
-- 
cgit v0.12


From 3ce94323a886abf6047135f188a6e10082a3e28d Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Wed, 21 Oct 2009 12:14:30 +0200
Subject: fix editable comboboxes in the Windows mobile style

In editable QComboBoxes we used cutting-edge technology to display the
text. But that's not always wanted. We actually want to see all pixels
of a string like "why oh why". The lower edge was cut off.

Reviewed-by: thartman
---
 src/gui/styles/qwindowsmobilestyle.cpp | 104 +++++++++++++++++++++++----------
 1 file changed, 73 insertions(+), 31 deletions(-)

diff --git a/src/gui/styles/qwindowsmobilestyle.cpp b/src/gui/styles/qwindowsmobilestyle.cpp
index a617102..5fa6251 100644
--- a/src/gui/styles/qwindowsmobilestyle.cpp
+++ b/src/gui/styles/qwindowsmobilestyle.cpp
@@ -5592,8 +5592,43 @@ void QWindowsMobileStyle::drawControl(ControlElement element, const QStyleOption
                          painter->drawLine(rect.bottomLeft(), rect.bottomRight());
              }
 #endif // QT_NO_SCROLLAREA
-            break; }
-
+            break;
+        }
+#ifndef QT_NO_COMBOBOX
+    case CE_ComboBoxLabel:
+        // This is copied from qcommonstyle.cpp with the difference, that
+        // the editRect isn't adjusted when calling drawItemText.
+        if (const QStyleOptionComboBox *cb = qstyleoption_cast<const QStyleOptionComboBox *>(option)) {
+            QRect editRect = proxy()->subControlRect(CC_ComboBox, cb, SC_ComboBoxEditField, widget);
+            painter->save();
+            painter->setClipRect(editRect);
+            if (!cb->currentIcon.isNull()) {
+                QIcon::Mode mode = cb->state & State_Enabled ? QIcon::Normal
+                                                             : QIcon::Disabled;
+                QPixmap pixmap = cb->currentIcon.pixmap(cb->iconSize, mode);
+                QRect iconRect(editRect);
+                iconRect.setWidth(cb->iconSize.width() + 4);
+                iconRect = alignedRect(cb->direction,
+                                       Qt::AlignLeft | Qt::AlignVCenter,
+                                       iconRect.size(), editRect);
+                if (cb->editable)
+                    painter->fillRect(iconRect, option->palette.brush(QPalette::Base));
+                proxy()->drawItemPixmap(painter, iconRect, Qt::AlignCenter, pixmap);
+
+                if (cb->direction == Qt::RightToLeft)
+                    editRect.translate(-4 - cb->iconSize.width(), 0);
+                else
+                    editRect.translate(cb->iconSize.width() + 4, 0);
+            }
+            if (!cb->currentText.isEmpty() && !cb->editable) {
+                proxy()->drawItemText(painter, editRect,
+                             visualAlignment(cb->direction, Qt::AlignLeft | Qt::AlignVCenter),
+                             cb->palette, cb->state & State_Enabled, cb->currentText);
+            }
+            painter->restore();
+        }
+        break;
+#endif // QT_NO_COMBOBOX
 #ifndef QT_NO_DOCKWIDGET
     case CE_DockWidgetTitle:
         if (const QStyleOptionDockWidget *dwOpt = qstyleoption_cast<const QStyleOptionDockWidget *>(option)) {
@@ -6154,24 +6189,24 @@ void QWindowsMobileStyle::drawComplexControl(ComplexControl control, const QStyl
                 qDrawPlainRect(painter, option->rect, option->palette.shadow().color(), proxy()->pixelMetric(PM_ComboBoxFrameWidth, option, widget), &editBrush);
             else
                 painter->fillRect(option->rect, editBrush);
-                State flags = State_None;
-                QRect ar = proxy()->subControlRect(CC_ComboBox, cmb, SC_ComboBoxArrow, widget);
-                if ((option->state & State_On)) {
-                  painter->fillRect(ar.adjusted(0, 0, 1, 1),cmb->palette.brush(QPalette::Shadow));
-                }
-                if (d->doubleControls)
-                  ar.adjust(5, 0, 5, 0);
-                else
-                  ar.adjust(2, 0, -2, 0);
-                if (option->state & State_Enabled)
-                    flags |= State_Enabled;
-                if (option->state & State_On)
-                    flags |= State_Sunken;
-                QStyleOption arrowOpt(0);
-                arrowOpt.rect = ar;
-                arrowOpt.palette = cmb->palette;
-                arrowOpt.state = flags;
-                proxy()->drawPrimitive(PrimitiveElement(PE_IndicatorArrowDownBig), &arrowOpt, painter, widget);
+            State flags = State_None;
+            QRect ar = proxy()->subControlRect(CC_ComboBox, cmb, SC_ComboBoxArrow, widget);
+            if ((option->state & State_On)) {
+                painter->fillRect(ar.adjusted(0, 0, 1, 1),cmb->palette.brush(QPalette::Shadow));
+            }
+            if (d->doubleControls)
+                ar.adjust(5, 0, 5, 0);
+            else
+                ar.adjust(2, 0, -2, 0);
+            if (option->state & State_Enabled)
+                flags |= State_Enabled;
+            if (option->state & State_On)
+                flags |= State_Sunken;
+            QStyleOption arrowOpt(0);
+            arrowOpt.rect = ar;
+            arrowOpt.palette = cmb->palette;
+            arrowOpt.state = flags;
+            proxy()->drawPrimitive(PrimitiveElement(PE_IndicatorArrowDownBig), &arrowOpt, painter, widget);
             if (cmb->subControls & SC_ComboBoxEditField) {
                 QRect re = proxy()->subControlRect(CC_ComboBox, cmb, SC_ComboBoxEditField, widget);
                 if (cmb->state & State_HasFocus && !cmb->editable)
@@ -6335,7 +6370,7 @@ QSize QWindowsMobileStyle::sizeFromContents(ContentsType type, const QStyleOptio
     case CT_ComboBox:
         if (const QStyleOptionComboBox *comboBox = qstyleoption_cast<const QStyleOptionComboBox *>(option)) {
             int fw = comboBox->frame ? proxy()->pixelMetric(PM_ComboBoxFrameWidth, option, widget) * 2 : 0;
-            newSize = QSize(newSize.width() + fw + 9, newSize.height() + fw-4); //Nine is a magic Number - See CommonStyle for real magic (23)
+            newSize = QSize(newSize.width() + fw + 9, newSize.height() + fw); //Nine is a magic Number - See CommonStyle for real magic (23)
         }
         break;
 #endif
@@ -6618,14 +6653,21 @@ QRect QWindowsMobileStyle::subControlRect(ComplexControl control, const QStyleOp
         switch (subControl) {
         case SC_ComboBoxArrow:
             rect.setRect(xpos, y + bmarg, he - 2*bmarg, he - 2*bmarg);
-            rect.setRect(xpos, y + bmarg, int((he - 2*bmarg)), he - 2*bmarg);
             break;
-         case SC_ComboBoxEditField:
-             rect.setRect(x + margin+4, y + margin+2, wi - 4 * margin - int((he - 2*bmarg) * 0.84f) -2, he - 2 * margin-4);
-             break;
-          case SC_ComboBoxFrame:
-              rect = comboBox->rect;
-              break;
+        case SC_ComboBoxEditField:
+            rect.setRect(x + margin, y + margin, wi - 2 * margin - int((he - 2*bmarg) * 0.84f), he - 2 * margin);
+            if (d->doubleControls) {
+                if (comboBox->editable)
+                    rect.adjust(2, 0, 0, 0);
+                else
+                    rect.adjust(4, 2, 0, -2);
+            } else if (!comboBox->editable) {
+                rect.adjust(2, 1, 0, -1);
+            }
+            break;
+        case SC_ComboBoxFrame:
+            rect = comboBox->rect;
+            break;
         default:
         break;
         }
@@ -6999,7 +7041,7 @@ int QWindowsMobileStyle::pixelMetric(PixelMetric pm, const QStyleOption *opt, co
        } else {
            d->doubleControls ? ret = 36 : ret = 18;
        }
-        break;        
+        break;
    case PM_ScrollBarExtent: {
        
        if (d->smartphone)
@@ -7055,7 +7097,7 @@ int QWindowsMobileStyle::pixelMetric(PixelMetric pm, const QStyleOption *opt, co
         break;
     case PM_TextCursorWidth:
         ret = 2;
-        break;        
+        break;
     case PM_TabBar_ScrollButtonOverlap:
         ret = 0;
         break;
@@ -7089,7 +7131,7 @@ int QWindowsMobileStyle::styleHint(StyleHint hint, const QStyleOption *opt, cons
 #endif
     case SH_ToolBar_Movable:
         ret = false;
-        break;    
+        break;
     case SH_ScrollBar_ContextMenu:
         ret = false;
         break;
-- 
cgit v0.12


From 5370e5ff5481a64a7d4a7c182155ce893740abe0 Mon Sep 17 00:00:00 2001
From: axis <qt-info@nokia.com>
Date: Tue, 20 Oct 2009 15:15:51 +0200
Subject: Cleaned up the API of the Symbian event hooks.

The two major points were:
- Replacing "s60" with "symbian" in all event handling functions,
  since there is nothing S60-specific about them.
- Replace the Symbian event types with the encapsulating
  QSymbianEvent container. This allows us to cope with more types of
  events in the future without having to add new virtual functions.

AutoTest: QWidget passed
Task:     QT-1156
RevBy:    Jason Barron
RevBy:    Shane Kearns
RevBy:    Sami Merila
---
 src/gui/inputmethod/qinputcontext.cpp  |  14 ++--
 src/gui/inputmethod/qinputcontext.h    |  13 ++-
 src/gui/kernel/qapplication.h          |  12 ++-
 src/gui/kernel/qapplication_p.h        |   5 ++
 src/gui/kernel/qapplication_s60.cpp    | 108 +++++++++++++++----------
 src/gui/kernel/symbian.pri             |   3 +
 src/gui/s60framework/qs60mainappui.cpp |  23 ++++--
 src/gui/styles/qs60style.h             |   2 +-
 src/gui/symbian/qsymbianevent.cpp      | 143 +++++++++++++++++++++++++++++++++
 src/gui/symbian/qsymbianevent.h        | 104 ++++++++++++++++++++++++
 src/gui/widgets/qmenu_symbian.cpp      |   8 +-
 src/gui/widgets/qmenubar_p.h           |   2 +-
 12 files changed, 361 insertions(+), 76 deletions(-)
 create mode 100644 src/gui/symbian/qsymbianevent.cpp
 create mode 100644 src/gui/symbian/qsymbianevent.h

diff --git a/src/gui/inputmethod/qinputcontext.cpp b/src/gui/inputmethod/qinputcontext.cpp
index 8ee417f..ea6ed35 100644
--- a/src/gui/inputmethod/qinputcontext.cpp
+++ b/src/gui/inputmethod/qinputcontext.cpp
@@ -467,32 +467,32 @@ bool QInputContext::x11FilterEvent(QWidget * /*keywidget*/, XEvent * /*event*/)
 }
 #endif // Q_WS_X11
 
-#ifdef Q_WS_S60
+#ifdef Q_OS_SYMBIAN
 /*!
     \since 4.6
 
     This function may be overridden only if input method is depending
-    on Symbian and you need raw TWsEvent. Otherwise, this function must not.
+    on Symbian and you need raw Symbian events. Otherwise, this function must not.
 
-    This function is designed to filter raw key events on S60, but
+    This function is designed to filter raw key events on Symbian, but
     other input methods may use this to implement some special
     features.
 
     Return true if the \a event has been consumed. Otherwise, the
     unfiltered \a event will be translated into QEvent and forwarded
-    to filterEvent(). Filtering at both s60FilterEvent() and
+    to filterEvent(). Filtering at both symbianFilterEvent() and
     filterEvent() in single input method is allowed.
 
     \a keywidget is a client widget into which a text is inputted. \a
-    event is inputted TWsEvent.
+    event is inputted QSymbianEvent.
 
     \sa filterEvent()
 */
-bool QInputContext::s60FilterEvent(QWidget * /*keywidget*/, TWsEvent * /*event*/)
+bool QInputContext::symbianFilterEvent(QWidget * /*keywidget*/, const QSymbianEvent * /*event*/)
 {
     return false;
 }
-#endif // Q_WS_S60
+#endif // Q_OS_SYMBIAN
 
 QT_END_NAMESPACE
 
diff --git a/src/gui/inputmethod/qinputcontext.h b/src/gui/inputmethod/qinputcontext.h
index 73b05d8..14096e3 100644
--- a/src/gui/inputmethod/qinputcontext.h
+++ b/src/gui/inputmethod/qinputcontext.h
@@ -67,10 +67,6 @@
 
 QT_BEGIN_HEADER
 
-#ifdef Q_WS_S60
-class TWsEvent;
-#endif
-
 QT_BEGIN_NAMESPACE
 
 QT_MODULE(Gui)
@@ -79,6 +75,9 @@ class QWidget;
 class QFont;
 class QPopupMenu;
 class QInputContextPrivate;
+#ifdef Q_OS_SYMBIAN
+class QSymbianEvent;
+#endif
 
 class Q_GUI_EXPORT QInputContext : public QObject
 {
@@ -108,9 +107,9 @@ public:
 #if defined(Q_WS_X11)
     virtual bool x11FilterEvent( QWidget *keywidget, XEvent *event );
 #endif // Q_WS_X11
-#if defined(Q_WS_S60)
-    virtual bool s60FilterEvent( QWidget *keywidget, TWsEvent *event );
-#endif // Q_WS_S60
+#if defined(Q_OS_SYMBIAN)
+    virtual bool symbianFilterEvent( QWidget *keywidget, const QSymbianEvent *event );
+#endif // Q_OS_SYMBIAN
     virtual bool filterEvent( const QEvent *event );
 
     void sendEvent(const QInputMethodEvent &event);
diff --git a/src/gui/kernel/qapplication.h b/src/gui/kernel/qapplication.h
index 12b398d..5a8e325 100644
--- a/src/gui/kernel/qapplication.h
+++ b/src/gui/kernel/qapplication.h
@@ -61,9 +61,6 @@
 
 QT_BEGIN_HEADER
 
-#if defined(Q_OS_SYMBIAN)
-class TWsEvent;
-#endif
 #if defined(Q_WS_S60)
 class CApaApplication;
 #endif
@@ -83,6 +80,9 @@ class QLocale;
 #if defined(Q_WS_QWS)
 class QDecoration;
 #endif
+#if defined(Q_OS_SYMBIAN)
+class QSymbianEvent;
+#endif
 
 class QApplication;
 class QApplicationPrivate;
@@ -241,10 +241,8 @@ public:
     int x11ProcessEvent(XEvent*);
 #endif
 #if defined(Q_OS_SYMBIAN)
-    int s60ProcessEvent(TWsEvent *event);
-    virtual bool s60EventFilter(TWsEvent *aEvent);
-    void symbianHandleCommand(int command);
-    void symbianResourceChange(int type);
+    int symbianProcessEvent(const QSymbianEvent *event);
+    virtual bool symbianEventFilter(const QSymbianEvent *event);
 #endif
 #if defined(Q_WS_QWS)
     virtual bool qwsEventFilter(QWSEvent *);
diff --git a/src/gui/kernel/qapplication_p.h b/src/gui/kernel/qapplication_p.h
index 2d3d18c..65f61e9 100644
--- a/src/gui/kernel/qapplication_p.h
+++ b/src/gui/kernel/qapplication_p.h
@@ -503,6 +503,11 @@ public:
     static void setNavigationMode(Qt::NavigationMode mode);
     static TUint resolveS60ScanCode(TInt scanCode, TUint keysym);
     QSet<WId> nativeWindows;
+
+    int symbianProcessWsEvent(const TWsEvent *event);
+    int symbianHandleCommand(int command);
+    int symbianResourceChange(int type);
+
 #endif
 #if defined(Q_WS_WIN) || defined(Q_WS_X11) || defined (Q_WS_QWS)
     void sendSyntheticEnterLeave(QWidget *widget);
diff --git a/src/gui/kernel/qapplication_s60.cpp b/src/gui/kernel/qapplication_s60.cpp
index 656bbc9..d6fdd02 100644
--- a/src/gui/kernel/qapplication_s60.cpp
+++ b/src/gui/kernel/qapplication_s60.cpp
@@ -42,6 +42,7 @@
 #include "qapplication_p.h"
 #include "qsessionmanager.h"
 #include "qevent.h"
+#include "qsymbianevent.h"
 #include "qeventdispatcher_s60_p.h"
 #include "qwidget.h"
 #include "qdesktopwidget.h"
@@ -1426,43 +1427,47 @@ void QApplication::beep()
     \warning This function is only available on Symbian.
     \since 4.6
 
-    This function processes an individual Symbian window server
+    This function processes an individual Symbian event
     \a event. It returns 1 if the event was handled, 0 if
     the \a event was not handled, and -1 if the event was
-    not handled because the event handle (\c{TWsEvent::Handle()})
-    is not known to Qt.
+    not handled because the event is not known to Qt.
  */
-int QApplication::s60ProcessEvent(TWsEvent *event)
+
+int QApplication::symbianProcessEvent(const QSymbianEvent *event)
 {
-    bool handled = s60EventFilter(event);
-    if (handled)
+    Q_D(QApplication);
+
+    QScopedLoopLevelCounter counter(d->threadData);
+
+    QWidget *w = qApp ? qApp->focusWidget() : 0;
+    if (w) {
+        QInputContext *ic = w->inputContext();
+        if (ic && ic->symbianFilterEvent(w, event))
+            return 1;
+    }
+
+    if (symbianEventFilter(event))
         return 1;
 
+    switch (event->type()) {
+    case QSymbianEvent::WindowServerEvent:
+        return d->symbianProcessWsEvent(event->windowServerEvent());
+    case QSymbianEvent::CommandEvent:
+        return d->symbianHandleCommand(event->command());
+    case QSymbianEvent::ResourceChangeEvent:
+        return d->symbianResourceChange(event->resourceChangeType());
+    default:
+        return -1;
+    }
+}
+
+int QApplicationPrivate::symbianProcessWsEvent(const TWsEvent *event)
+{
     // Qt event handling. Handle some events regardless of if the handle is in our
     // widget map or not.
     CCoeControl* control = reinterpret_cast<CCoeControl*>(event->Handle());
     const bool controlInMap = QWidgetPrivate::mapper && QWidgetPrivate::mapper->contains(control);
     switch (event->Type()) {
-#if !defined(QT_NO_IM) && defined(Q_WS_S60)
-    case EEventKey:
-    case EEventKeyUp:
-    case EEventKeyDown:
-    {
-        // The control doesn't seem to be any of our widgets, so rely on the focused
-        // widget instead. If the user needs the control, it can be found inside the
-        // event structure.
-        QWidget *w = qApp ? qApp->focusWidget() : 0;
-        if (w) {
-            QInputContext *ic = w->inputContext();
-            if (ic && ic->s60FilterEvent(w, event)) {
-                return 1;
-            } else {
-                return 0;
-            }
-        }
-        break;
-    }
-#endif
     case EEventPointerEnter:
         if (controlInMap)
             return 1; // Qt::Enter will be generated in HandlePointerL
@@ -1551,15 +1556,15 @@ int QApplication::s60ProcessEvent(TWsEvent *event)
 
   If you create an application that inherits QApplication and reimplement
   this function, you get direct access to events that the are received
-  from the Symbian window server. The events are passed in the TWsEvent
-  \a aEvent parameter.
+  from Symbian. The events are passed in the \a event parameter.
 
   Return true if you want to stop the event from being processed. Return
-  false for normal event dispatching. The default implementation
-  false, and does nothing with \a aEvent.
+  false for normal event dispatching. The default implementation returns
+  false, and does nothing with \a event.
  */
-bool QApplication::s60EventFilter(TWsEvent * /* aEvent */)
+bool QApplication::symbianEventFilter(const QSymbianEvent *event)
 {
+    Q_UNUSED(event);
     return false;
 }
 
@@ -1574,32 +1579,39 @@ bool QApplication::s60EventFilter(TWsEvent * /* aEvent */)
 
   \sa s60EventFilter(), s60ProcessEvent()
 */
-void QApplication::symbianHandleCommand(int command)
+int QApplicationPrivate::symbianHandleCommand(int command)
 {
-    QScopedLoopLevelCounter counter(d_func()->threadData);
+    Q_Q(QApplication);
+    int ret = 0;
+
     switch (command) {
 #ifdef Q_WS_S60
     case EAknSoftkeyExit: {
         QCloseEvent ev;
-        QApplication::sendSpontaneousEvent(this, &ev);
-        if (ev.isAccepted())
-            quit();
+        QApplication::sendSpontaneousEvent(q, &ev);
+        if (ev.isAccepted()) {
+            q->quit();
+            ret = 1;
+        }
         break;
     }
 #endif
     case EEikCmdExit:
-        quit();
+        q->quit();
+        ret = 1;
         break;
     default:
         bool handled = QSoftKeyManager::handleCommand(command);
+        if (handled)
+            ret = 1;
 #ifdef Q_WS_S60
-        if (!handled)
-            QMenuBarPrivate::symbianCommands(command);
-#else
-        Q_UNUSED(handled);
+        else
+            ret = QMenuBarPrivate::symbianCommands(command);
 #endif
         break;
     }
+
+    return ret;
 }
 
 /*!
@@ -1611,8 +1623,10 @@ void QApplication::symbianHandleCommand(int command)
   Currently, KEikDynamicLayoutVariantSwitch and
   KAknsMessageSkinChange are handled.
  */
-void QApplication::symbianResourceChange(int type)
+int QApplicationPrivate::symbianResourceChange(int type)
 {
+    int ret = 0;
+
     switch (type) {
 #ifdef Q_WS_S60
     case KEikDynamicLayoutVariantSwitch:
@@ -1631,22 +1645,28 @@ void QApplication::symbianResourceChange(int type)
 #endif
             s60Style = qobject_cast<QS60Style*>(QApplication::style());
 
-        if (s60Style)
+        if (s60Style) {
             s60Style->d_func()->handleDynamicLayoutVariantSwitch();
+            ret = 1;
+        }
 #endif
         }
         break;
 
 #ifndef QT_NO_STYLE_S60
     case KAknsMessageSkinChange:
-        if (QS60Style *s60Style = qobject_cast<QS60Style*>(QApplication::style()))
+        if (QS60Style *s60Style = qobject_cast<QS60Style*>(QApplication::style())) {
             s60Style->d_func()->handleSkinChange();
+            ret = 1;
+        }
         break;
 #endif
 #endif // Q_WS_S60
     default:
         break;
     }
+
+    return ret;
 }
 
 #ifndef QT_NO_WHEELEVENT
diff --git a/src/gui/kernel/symbian.pri b/src/gui/kernel/symbian.pri
index 5497ccb..69422dd 100644
--- a/src/gui/kernel/symbian.pri
+++ b/src/gui/kernel/symbian.pri
@@ -1,4 +1,7 @@
 symbian {
     contains(QT_CONFIG, s60): LIBS+= $$QMAKE_LIBS_S60
     RESOURCES += symbian/symbianresources.qrc
+
+    HEADERS += symbian/qsymbianevent.h
+    SOURCES += symbian/qsymbianevent.cpp
 }
diff --git a/src/gui/s60framework/qs60mainappui.cpp b/src/gui/s60framework/qs60mainappui.cpp
index e630253..4ad78f9 100644
--- a/src/gui/s60framework/qs60mainappui.cpp
+++ b/src/gui/s60framework/qs60mainappui.cpp
@@ -50,6 +50,7 @@
 
 #include "qs60mainappui.h"
 #include <QtGui/qapplication.h>
+#include <QtGui/qsymbianevent.h>
 #include <QtGui/qmenu.h>
 #include <private/qmenu_p.h>
 #include <private/qt_s60_p.h>
@@ -134,8 +135,10 @@ QS60MainAppUi::~QS60MainAppUi()
  */
 void QS60MainAppUi::HandleCommandL(TInt command)
 {
-    if (qApp)
-        QT_TRYCATCH_LEAVING(qApp->symbianHandleCommand(command));
+    if (qApp) {
+        QSymbianEvent event(QSymbianEvent::CommandEvent, command);
+        QT_TRYCATCH_LEAVING(qApp->symbianProcessEvent(&event));
+    }
 }
 
 /*!
@@ -151,8 +154,10 @@ void QS60MainAppUi::HandleResourceChangeL(TInt type)
 {
     CAknAppUi::HandleResourceChangeL(type);
 
-    if (qApp)
-        QT_TRYCATCH_LEAVING(qApp->symbianResourceChange(type));
+    if (qApp) {
+        QSymbianEvent event(QSymbianEvent::ResourceChangeEvent, type);
+        QT_TRYCATCH_LEAVING(qApp->symbianProcessEvent(&event));
+    }
 }
 
 /*!
@@ -164,16 +169,18 @@ void QS60MainAppUi::HandleResourceChangeL(TInt type)
  * If you override this function, you should call the base class implementation if you do not
  * handle the event.
  */
-void QS60MainAppUi::HandleWsEventL(const TWsEvent& event, CCoeControl *destination)
+void QS60MainAppUi::HandleWsEventL(const TWsEvent& wsEvent, CCoeControl *destination)
 {
     int result = 0;
-    if (qApp)
+    if (qApp) {
+        QSymbianEvent event(&wsEvent);
         QT_TRYCATCH_LEAVING(
-            result = qApp->s60ProcessEvent(const_cast<TWsEvent*>(&event))
+            result = qApp->symbianProcessEvent(&event)
         );
+    }
 
     if (result <= 0)
-        CAknAppUi::HandleWsEventL(event, destination);
+        CAknAppUi::HandleWsEventL(wsEvent, destination);
 }
 
 
diff --git a/src/gui/styles/qs60style.h b/src/gui/styles/qs60style.h
index 6be3197..ab10792 100644
--- a/src/gui/styles/qs60style.h
+++ b/src/gui/styles/qs60style.h
@@ -101,7 +101,7 @@ protected Q_SLOTS:
 private:
     Q_DISABLE_COPY(QS60Style)
     friend class QStyleFactory;
-    friend class QApplication;
+    friend class QApplicationPrivate;
 };
 
 #endif // QT_NO_STYLE_S60
diff --git a/src/gui/symbian/qsymbianevent.cpp b/src/gui/symbian/qsymbianevent.cpp
new file mode 100644
index 0000000..af2c861
--- /dev/null
+++ b/src/gui/symbian/qsymbianevent.cpp
@@ -0,0 +1,143 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qsymbianevent.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QSymbianEvent
+    \brief The QSymbianEvent class contains a Symbian event of any type.
+    \since 4.6
+
+    The class is used as a generic container type for all types of Symbian
+    events.
+
+    \note This class is only available on Symbian.
+
+    \sa QApplication::symbianEventFilter()
+*/
+
+/*!
+    \enum QSymbianEvent::Type
+
+    \value InvalidEvent        The event is not valid.
+    \value WindowServerEvent   Indicates an event of type \c TWsEvent.
+    \value CommandEvent        Indicates that the event is a Symbian command.
+    \value ResourceChangeEvent Indicates that the event is a Symbian resource change type.
+*/
+
+/*!
+    \fn QSymbianEvent::type()
+
+    Returns the event type contained in the QSymbianEvent instance.
+*/
+
+/*!
+    \fn QSymbianEvent::isValid()
+
+    Returns whether this QSymbianEvent instance contains a valid event.
+*/
+
+/*!
+    Constructs a QSymbianEvent containing the given window server event
+    \a windowServerEvent.
+*/
+QSymbianEvent::QSymbianEvent(const TWsEvent *windowServerEvent)
+    : m_type(WindowServerEvent)
+    , m_eventPtr(windowServerEvent)
+{
+}
+
+/*!
+    Constructs a QSymbianEvent containing the given event value
+    \a value. The type of event is controlled by the \a eventType parameter.
+*/
+QSymbianEvent::QSymbianEvent(QSymbianEvent::Type eventType, int value)
+{
+    switch (eventType) {
+    case CommandEvent:
+    case ResourceChangeEvent:
+        m_type = eventType;
+        m_eventValue = value;
+        break;
+    default:
+        m_type = InvalidEvent;
+        m_eventValue = 0;
+        break;
+    }
+}
+
+/*!
+    Destroys the QSymbianEvent.
+*/
+QSymbianEvent::~QSymbianEvent()
+{
+}
+
+/*!
+    Returns the window server event contained in the class instance, or 0 if the event type
+    is not \c WindowServerEvent.
+*/
+const TWsEvent *QSymbianEvent::windowServerEvent() const
+{
+    return (m_type == WindowServerEvent) ? static_cast<const TWsEvent *>(m_eventPtr) : 0;
+}
+
+/*!
+    Returns the command contained in the class instance, or 0 if the event type
+    is not \c CommandEvent.
+*/
+int QSymbianEvent::command() const
+{
+    return (m_type == CommandEvent) ? m_eventValue : 0;
+}
+
+/*!
+    Returns the resource change type contained in the class instance, or 0 if the event type
+    is not \c ResourceChangeEvent.
+*/
+int QSymbianEvent::resourceChangeType() const
+{
+    return (m_type == ResourceChangeEvent) ? m_eventValue : 0;
+}
+
+QT_END_NAMESPACE
diff --git a/src/gui/symbian/qsymbianevent.h b/src/gui/symbian/qsymbianevent.h
new file mode 100644
index 0000000..74aa5d0
--- /dev/null
+++ b/src/gui/symbian/qsymbianevent.h
@@ -0,0 +1,104 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QSYMBIANEVENT_H
+#define QSYMBIANEVENT_H
+
+#include <QtCore/qglobal.h>
+
+#ifdef Q_OS_SYMBIAN
+
+class TWsEvent;
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+QT_MODULE(Gui)
+
+class Q_GUI_EXPORT QSymbianEvent
+{
+public:
+    enum Type {
+        InvalidEvent,
+        WindowServerEvent,
+        CommandEvent,
+        ResourceChangeEvent
+    };
+
+    QSymbianEvent(const TWsEvent *windowServerEvent);
+    QSymbianEvent(Type eventType, int value);
+    ~QSymbianEvent();
+
+    Type type() const;
+    bool isValid() const;
+
+    const TWsEvent *windowServerEvent() const;
+    int command() const;
+    int resourceChangeType() const;
+
+private:
+    Type m_type;
+    union {
+        const void *m_eventPtr;
+        int m_eventValue;
+
+        qint64 m_reserved;
+    };
+};
+
+inline QSymbianEvent::Type QSymbianEvent::type() const
+{
+    return m_type;
+}
+
+inline bool QSymbianEvent::isValid() const
+{
+    return m_type != InvalidEvent;
+}
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // Q_OS_SYMBIAN
+
+#endif // QSYMBIANEVENT_H
diff --git a/src/gui/widgets/qmenu_symbian.cpp b/src/gui/widgets/qmenu_symbian.cpp
index d757f98..94c4177 100644
--- a/src/gui/widgets/qmenu_symbian.cpp
+++ b/src/gui/widgets/qmenu_symbian.cpp
@@ -243,11 +243,14 @@ void qt_symbian_show_submenu( CEikMenuPane* menuPane, int id)
 }
 #endif // Q_WS_S60
 
-void QMenuBarPrivate::symbianCommands(int command)
+int QMenuBarPrivate::symbianCommands(int command)
 {
+    int ret = 0;
+
     if (command == contexMenuCommand && !widgetWithContextMenu.isNull()) {
         QContextMenuEvent* event = new QContextMenuEvent(QContextMenuEvent::Keyboard, QPoint(0,0));
         QCoreApplication::postEvent(widgetWithContextMenu, event);
+        ret = 1;
     }
 
     int size = nativeMenuBars.size();
@@ -258,8 +261,11 @@ void QMenuBarPrivate::symbianCommands(int command)
 
         emit nativeMenuBars.at(i)->triggered(menu->action);
         menu->action->activate(QAction::Trigger);
+        ret = 1;
         break;
     }
+
+    return ret;
 }
 
 void QMenuBarPrivate::symbianCreateMenuBar(QWidget *parent)
diff --git a/src/gui/widgets/qmenubar_p.h b/src/gui/widgets/qmenubar_p.h
index 7815969..da2b8d7 100644
--- a/src/gui/widgets/qmenubar_p.h
+++ b/src/gui/widgets/qmenubar_p.h
@@ -266,7 +266,7 @@ public:
         void insertNativeMenuItems(const QList<QAction*> &actions);
 
     } *symbian_menubar;
-    static void symbianCommands(int command);
+    static int symbianCommands(int command);
 
 #endif
 };
-- 
cgit v0.12


From 522fc01a18b9eae80b733befb98a948f0fbbba06 Mon Sep 17 00:00:00 2001
From: Shane Kearns <shane.kearns@sosco.com>
Date: Wed, 21 Oct 2009 13:52:07 +0200
Subject: Make Symbian emulator behave the same as device for mouse &
 touchscreen

Emulator HAL reports that it supports mouse but not touch.
Since Qt is changing behaviour based on these values, the emulator works
differently from the device.

To workaround, the emulator HAL values are ignored and following used:
5.0: mouse 0, touch 1
3.x: mouse 0, touch 0

The mouse can still be used to interact with the emulator, as pointer
events are still delivered.

Task-number: QTBUG-4803
Task-number: QTBUG-4616
Reviewed-by: Sami Merila
---
 src/gui/kernel/qapplication_s60.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/gui/kernel/qapplication_s60.cpp b/src/gui/kernel/qapplication_s60.cpp
index d6fdd02..689429e 100644
--- a/src/gui/kernel/qapplication_s60.cpp
+++ b/src/gui/kernel/qapplication_s60.cpp
@@ -1092,6 +1092,13 @@ void qt_init(QApplicationPrivate * /* priv */, int)
     err = HAL::Get(HALData::EPen, touch);
     if (err != KErrNone || touchIsUnsupportedOnSystem)
         touch = 0;
+#ifdef __WINS__
+    if(QSysInfo::symbianVersion() <= QSysInfo::SV_9_4) {
+        //for symbian SDK emulator, force values to match typical devices.
+        mouse = 0;
+        touch = touchIsUnsupportedOnSystem ? 0 : 1;
+    }
+#endif
     if (mouse || machineUID == KMachineUidSamsungI8510) {
         S60->hasTouchscreen = false;
         S60->virtualMouseRequired = false;
-- 
cgit v0.12


From 8e9b7dc23c7fde1d9970cd83b3283260b881f5e9 Mon Sep 17 00:00:00 2001
From: ck <qt-info@nokia.com>
Date: Wed, 21 Oct 2009 15:33:15 +0200
Subject: Assistant: More useful error messages for help collections.

---
 tools/assistant/lib/qhelpcollectionhandler.cpp | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/tools/assistant/lib/qhelpcollectionhandler.cpp b/tools/assistant/lib/qhelpcollectionhandler.cpp
index f59b227..4aa7ab6 100644
--- a/tools/assistant/lib/qhelpcollectionhandler.cpp
+++ b/tools/assistant/lib/qhelpcollectionhandler.cpp
@@ -76,7 +76,8 @@ bool QHelpCollectionHandler::isDBOpened()
 {
     if (m_dbOpened)
         return true;
-    emit error(tr("The collection file is not set up yet!"));
+    emit error(tr("The collection file '%1' is not set up yet!").
+               arg(m_collectionFile));
     return false;
 }
 
@@ -134,7 +135,8 @@ bool QHelpCollectionHandler::copyCollectionFile(const QString &fileName)
 
     QFileInfo fi(fileName);
     if (fi.exists()) {
-        emit error(tr("The specified collection file already exists!"));
+        emit error(tr("The collection file '%1' already exists!").
+                   arg(fileName));
         return false;
     }
 
@@ -281,7 +283,7 @@ bool QHelpCollectionHandler::removeCustomFilter(const QString &filterName)
         filterNameId = m_query.value(0).toInt();
 
     if (filterNameId < 0) {
-        emit error(tr("Unknown filter!"));
+        emit error(tr("Unknown filter '%1'!").arg(filterName));
         return false;
     }
 
@@ -386,7 +388,7 @@ bool QHelpCollectionHandler::registerDocumentation(const QString &fileName)
 
     QString ns = reader.namespaceName();
     if (ns.isEmpty()) {
-        emit error(tr("Invalid documentation file!"));
+        emit error(tr("Invalid documentation file '%1'!").arg(fileName));
         return false;
     }
 
@@ -553,7 +555,7 @@ int QHelpCollectionHandler::registerNamespace(const QString &nspace, const QStri
     if (m_query.exec())
         namespaceId = m_query.lastInsertId().toInt();
     if (namespaceId < 1) {
-        emit error(tr("Cannot register namespace!"));
+        emit error(tr("Cannot register namespace '%1'!").arg(nspace));
         return -1;
     }
     return namespaceId;
@@ -577,7 +579,7 @@ void QHelpCollectionHandler::optimizeDatabase(const QString &fileName)
         db.setDatabaseName(fileName);
         if (!db.open()) {
             QSqlDatabase::removeDatabase(QLatin1String("optimize"));
-            emit error(tr("Cannot open database to optimize!"));
+            emit error(tr("Cannot open database '%1' to optimize!").arg(fileName));
             return;
         }
 
-- 
cgit v0.12


From e7e687f737c19eda884448b6991836a102f0f3f4 Mon Sep 17 00:00:00 2001
From: Gareth Stockwell <gareth.stockwell@accenture.com>
Date: Wed, 21 Oct 2009 14:14:26 +0100
Subject: Fixed logical error in winIdChanged auto test.

The test (see 02fbfdbd) previously asserted that changing the parent
of a native widget caused a WinIdChange event on Symbian, but not on
other platforms.  The test now asserts that:

1. Changing the parent of a native widget causes a WinIdChange
event on all platforms.
2. Changing the grandparent of a native widget causes a WinIdChange
event only on Symbian.

Reviewed-by: Paul Olav Tvete
---
 tests/auto/qwidget/tst_qwidget.cpp | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/auto/qwidget/tst_qwidget.cpp b/tests/auto/qwidget/tst_qwidget.cpp
index a03f112..050d1c5 100644
--- a/tests/auto/qwidget/tst_qwidget.cpp
+++ b/tests/auto/qwidget/tst_qwidget.cpp
@@ -4391,12 +4391,27 @@ void tst_QWidget::winIdChangeEvent()
 
     {
         // Changing parent of a native widget
+        // Should cause winId of child to change, on all platforms
         QWidget parent1, parent2;
         WinIdChangeWidget child(&parent1);
         const WId winIdBefore = child.winId();
         QCOMPARE(child.m_winIdChangeEventCount, 1);
         child.setParent(&parent2);
         const WId winIdAfter = child.internalWinId();
+        QVERIFY(winIdBefore != winIdAfter);
+        QCOMPARE(child.m_winIdChangeEventCount, 2);
+    }
+
+    {
+        // Changing grandparent of a native widget
+        // Should cause winId of grandchild to change only on Symbian
+        QWidget grandparent1, grandparent2;
+        QWidget parent(&grandparent1);
+        WinIdChangeWidget child(&parent);
+        const WId winIdBefore = child.winId();
+        QCOMPARE(child.m_winIdChangeEventCount, 1);
+        parent.setParent(&grandparent2);
+        const WId winIdAfter = child.internalWinId();
 #ifdef Q_OS_SYMBIAN
         QVERIFY(winIdBefore != winIdAfter);
         QCOMPARE(child.m_winIdChangeEventCount, 2);
-- 
cgit v0.12


From bc2de3fbcc3f19c80938bdea17f01aa7da9f055e Mon Sep 17 00:00:00 2001
From: Frans Englich <frans.englich@nokia.com>
Date: Wed, 21 Oct 2009 16:53:03 +0200
Subject: Listen on hasVideoChanged() instead of only checking hasVideo().

This means that when the backend's knowledge about the content's video
capability changes outside the LoadingState, it still work. This
apparently matters for the Helix backend. Patch supplied by Adookkattil
Saleem (Nokia-D/Dallas).

Reviewed-by: Gareth Stockwell
Reviewed-by: Frans Englich
---
 demos/qmediaplayer/mediaplayer.cpp | 8 ++++++--
 demos/qmediaplayer/mediaplayer.h   | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/demos/qmediaplayer/mediaplayer.cpp b/demos/qmediaplayer/mediaplayer.cpp
index e1ceb0e..624bab7 100644
--- a/demos/qmediaplayer/mediaplayer.cpp
+++ b/demos/qmediaplayer/mediaplayer.cpp
@@ -321,6 +321,7 @@ MediaPlayer::MediaPlayer(const QString &filePath,
     connect(&m_MediaObject, SIGNAL(finished()), this, SLOT(finished()));
     connect(&m_MediaObject, SIGNAL(stateChanged(Phonon::State, Phonon::State)), this, SLOT(stateChanged(Phonon::State, Phonon::State)));
     connect(&m_MediaObject, SIGNAL(bufferStatus(int)), this, SLOT(bufferStatus(int)));
+    connect(&m_MediaObject, SIGNAL(hasVideoChanged(bool)), this, SLOT(hasVideoChanged(bool)));
 
     rewindButton->setEnabled(false);
     playButton->setEnabled(false);
@@ -339,8 +340,6 @@ void MediaPlayer::stateChanged(Phonon::State newstate, Phonon::State oldstate)
     Q_UNUSED(oldstate);
 
     if (oldstate == Phonon::LoadingState) {
-        m_videoWindow.setVisible(m_MediaObject.hasVideo());
-        info->setVisible(!m_MediaObject.hasVideo());        
         QRect videoHintRect = QRect(QPoint(0, 0), m_videoWindow.sizeHint());
         QRect newVideoRect = QApplication::desktop()->screenGeometry().intersected(videoHintRect);
         if (!m_hasSmallScreen) {
@@ -846,3 +845,8 @@ void MediaPlayer::aspectChanged(QAction *act)
         m_videoWidget->setAspectRatio(Phonon::VideoWidget::AspectRatioAuto);    
 }
 
+void MediaPlayer::hasVideoChanged(bool bHasVideo)
+{
+    info->setVisible(!bHasVideo);
+    m_videoWindow.setVisible(bHasVideo);
+}
diff --git a/demos/qmediaplayer/mediaplayer.h b/demos/qmediaplayer/mediaplayer.h
index 40ffa40..83f14e8 100644
--- a/demos/qmediaplayer/mediaplayer.h
+++ b/demos/qmediaplayer/mediaplayer.h
@@ -93,6 +93,7 @@ public slots:
     void playPause();
     void scaleChanged(QAction *);
     void aspectChanged(QAction *);
+    void hasVideoChanged(bool);
 
 private slots:
     void setAspect(int);
-- 
cgit v0.12


From d043b59fedc41c774cc68eb49d9900dc6d36f3e5 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@nokia.com>
Date: Wed, 21 Oct 2009 18:27:40 +0200
Subject: windowsmobilelify embedded demos

Reviewed-by: aportale
---
 demos/embedded/digiflip/digiflip.cpp     | 8 ++++----
 demos/embedded/flickable/main.cpp        | 2 +-
 demos/embedded/lightmaps/lightmaps.cpp   | 4 ++--
 demos/embedded/raycasting/raycasting.cpp | 6 ++++--
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/demos/embedded/digiflip/digiflip.cpp b/demos/embedded/digiflip/digiflip.cpp
index 2edb752..9d6265d 100644
--- a/demos/embedded/digiflip/digiflip.cpp
+++ b/demos/embedded/digiflip/digiflip.cpp
@@ -117,7 +117,7 @@ protected:
     QPixmap drawDigits(int n, const QRect &rect) {
 
         int scaleFactor = 2;
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
         if (rect.height() > 240)
             scaleFactor = 1;
 #endif
@@ -192,7 +192,7 @@ protected:
 
     void paintFlip() {
         QPainter p(this);
-#if !defined(Q_OS_SYMBIAN)
+#if !defined(Q_OS_SYMBIAN) && !defined(Q_OS_WINCE_WM)
         p.setRenderHint(QPainter::SmoothPixmapTransform, true);
         p.setRenderHint(QPainter::Antialiasing, true);
 #endif
@@ -319,7 +319,7 @@ public:
         connect(slideAction, SIGNAL(triggered()), SLOT(chooseSlide()));
         connect(flipAction, SIGNAL(triggered()), SLOT(chooseFlip()));
         connect(rotateAction, SIGNAL(triggered()), SLOT(chooseRotate()));
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
         menuBar()->addAction(slideAction);
         menuBar()->addAction(flipAction);
         menuBar()->addAction(rotateAction);
@@ -414,7 +414,7 @@ int main(int argc, char *argv[])
     QApplication app(argc, argv);
 
     DigiFlip time;
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
     time.showMaximized();
 #else
     time.resize(320, 240);
diff --git a/demos/embedded/flickable/main.cpp b/demos/embedded/flickable/main.cpp
index 403085a..eb2c3c0 100644
--- a/demos/embedded/flickable/main.cpp
+++ b/demos/embedded/flickable/main.cpp
@@ -222,7 +222,7 @@ int main(int argc, char *argv[])
 
     ColorList list;
     list.setWindowTitle("Kinetic Scrolling");
-#ifdef Q_OS_SYMBIAN
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
     list.showMaximized();
 #else
     list.resize(320, 320);
diff --git a/demos/embedded/lightmaps/lightmaps.cpp b/demos/embedded/lightmaps/lightmaps.cpp
index 52297d2..ea34ae6 100644
--- a/demos/embedded/lightmaps/lightmaps.cpp
+++ b/demos/embedded/lightmaps/lightmaps.cpp
@@ -510,7 +510,7 @@ public:
         connect(nightModeAction, SIGNAL(triggered()), map, SLOT(toggleNightMode()));
         connect(osmAction, SIGNAL(triggered()), SLOT(aboutOsm()));
 
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
         menuBar()->addAction(osloAction);
         menuBar()->addAction(berlinAction);
         menuBar()->addAction(jakartaAction);
@@ -568,7 +568,7 @@ int main(int argc, char **argv)
 
     MapZoom w;
     w.setWindowTitle("OpenStreetMap");
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
     w.showMaximized();
 #else
     w.resize(600, 450);
diff --git a/demos/embedded/raycasting/raycasting.cpp b/demos/embedded/raycasting/raycasting.cpp
index c3b21b6..cb08b51 100644
--- a/demos/embedded/raycasting/raycasting.cpp
+++ b/demos/embedded/raycasting/raycasting.cpp
@@ -251,7 +251,9 @@ public:
 protected:
 
     void resizeEvent(QResizeEvent*) {
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_WINCE_WM)
+        touchDevice = true;
+#elif defined(Q_OS_SYMBIAN)
         // FIXME: use HAL
         if (width() > 480 || height() > 480)
             touchDevice = true;
@@ -378,7 +380,7 @@ int main(int argc, char **argv)
 
     Raycasting w;
     w.setWindowTitle("Raycasting");
-#if defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
     w.showMaximized();
 #else
     w.resize(640, 480);
-- 
cgit v0.12


From fad27a3b6f018a0bc3cb261c81aaefc540589585 Mon Sep 17 00:00:00 2001
From: Thiago Macieira <thiago.macieira@nokia.com>
Date: Wed, 21 Oct 2009 21:57:41 +0200
Subject: Rename the .cpp for QNetworkReply benchmark tests

---
 tests/benchmarks/qnetworkreply/main.cpp            | 74 ----------------------
 tests/benchmarks/qnetworkreply/qnetworkreply.pro   |  2 +-
 .../benchmarks/qnetworkreply/tst_qnetworkreply.cpp | 74 ++++++++++++++++++++++
 3 files changed, 75 insertions(+), 75 deletions(-)
 delete mode 100644 tests/benchmarks/qnetworkreply/main.cpp
 create mode 100644 tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp

diff --git a/tests/benchmarks/qnetworkreply/main.cpp b/tests/benchmarks/qnetworkreply/main.cpp
deleted file mode 100644
index 666e4f1..0000000
--- a/tests/benchmarks/qnetworkreply/main.cpp
+++ /dev/null
@@ -1,74 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
-** All rights reserved.
-** Contact: Nokia Corporation (qt-info@nokia.com)
-**
-** This file is part of the test suite of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** No Commercial Usage
-** This file contains pre-release code and may not be distributed.
-** You may use this file in accordance with the terms and conditions
-** contained in the Technology Preview License Agreement accompanying
-** this package.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL included in the
-** packaging of this file.  Please review the following information to
-** ensure the GNU Lesser General Public License version 2.1 requirements
-** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
-**
-** In addition, as a special exception, Nokia gives you certain additional
-** rights.  These rights are described in the Nokia Qt LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
-**
-** If you have questions regarding the use of this file, please contact
-** Nokia at qt-info@nokia.com.
-**
-**
-**
-**
-**
-**
-**
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-// This file contains benchmarks for QNetworkReply functions.
-
-#include <QDebug>
-#include <qtest.h>
-#include <QtTest/QtTest>
-#include <QtNetwork/qnetworkreply.h>
-#include <QtNetwork/qnetworkrequest.h>
-#include <QtNetwork/qnetworkaccessmanager.h>
-#include "../../auto/network-settings.h"
-
-class tst_qnetworkreply : public QObject
-{
-    Q_OBJECT
-private slots:
-    void httpLatency();
-
-};
-
-void tst_qnetworkreply::httpLatency()
-{
-    QNetworkAccessManager manager;
-    QBENCHMARK{
-        QNetworkRequest request(QUrl("http://" + QtNetworkSettings::serverName() + "/qtest/"));
-        QNetworkReply* reply = manager.get(request);
-        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
-        QTestEventLoop::instance().enterLoop(5);
-        QVERIFY(!QTestEventLoop::instance().timeout());
-        delete reply;
-    }
-}
-
-QTEST_MAIN(tst_qnetworkreply)
-
-#include "main.moc"
diff --git a/tests/benchmarks/qnetworkreply/qnetworkreply.pro b/tests/benchmarks/qnetworkreply/qnetworkreply.pro
index 060acf5..1e67d81 100644
--- a/tests/benchmarks/qnetworkreply/qnetworkreply.pro
+++ b/tests/benchmarks/qnetworkreply/qnetworkreply.pro
@@ -10,4 +10,4 @@ QT += network
 CONFIG += release
 
 # Input
-SOURCES += main.cpp
+SOURCES += tst_qnetworkreply.cpp
diff --git a/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
new file mode 100644
index 0000000..666e4f1
--- /dev/null
+++ b/tests/benchmarks/qnetworkreply/tst_qnetworkreply.cpp
@@ -0,0 +1,74 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+// This file contains benchmarks for QNetworkReply functions.
+
+#include <QDebug>
+#include <qtest.h>
+#include <QtTest/QtTest>
+#include <QtNetwork/qnetworkreply.h>
+#include <QtNetwork/qnetworkrequest.h>
+#include <QtNetwork/qnetworkaccessmanager.h>
+#include "../../auto/network-settings.h"
+
+class tst_qnetworkreply : public QObject
+{
+    Q_OBJECT
+private slots:
+    void httpLatency();
+
+};
+
+void tst_qnetworkreply::httpLatency()
+{
+    QNetworkAccessManager manager;
+    QBENCHMARK{
+        QNetworkRequest request(QUrl("http://" + QtNetworkSettings::serverName() + "/qtest/"));
+        QNetworkReply* reply = manager.get(request);
+        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(5);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        delete reply;
+    }
+}
+
+QTEST_MAIN(tst_qnetworkreply)
+
+#include "main.moc"
-- 
cgit v0.12